BRAC UNIVERSITY COURSES

CSE 101 LECTURE 5

noreply@blogger.com (TANVIR) — Sat, 20 Aug 2011 14:40:00 +0600

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Slide 2
Computer science:
Computer science is concerned with theory and fundamentals; Software engineering is concerned with the practicalities of developing and delivering useful software. Computer science theories are still insufficient to act as a complete underpinning for Software engineering (unlike e.g. physics and electrical engineering). Computer science theories are currently insufficient to act as a complete underpinning for software engineering, BUT it is a foundation for practical aspects of software engineering
Software engineering is an engineering discipline which is concerned with all aspects of software production. Software engineers should
adopt a systematic and organised approach to their work use appropriate tools and techniques depending on the problem to be solved, the development constraints and the resources available. Software engineering is part of this process concerned with developing the software infrastructure, control, applications and databases in the system. So this is a part of System engineering. System engineers are involved in system specification, architectural design Integration.
System Engineering is concerned with all aspects of computer-based systems development including hardware, software and process engineering. Systems engineering signifies both an approach and, more recently, a discipline in engineering. The aim of education in systems engineering is to simply formalize the approach and in doing so, identify new methods and research opportunities similar to the way it occurs in other fields of engineering. As an approach, systems engineering is holistic and interdisciplinary in flavor.
Slide - 8
Waterfall Model
The waterfall model is a popular version of the systems development life cycle model for software engineering. Often considered the classic approach to the systems development life cycle, the waterfall model describes a development method that is linear and sequential. Waterfall development has distinct goals for each phase of development. Imagine a waterfall on the cliff of a steep mountain. Once the water has flowed over the edge of the cliff and has begun its journey down the side of the mountain, it cannot turn back. It is the same with waterfall development. Once a phase of development is completed, the development proceeds to the next phase and there is no turning back.
System Feasibility: Defining a preferred concept for the software product, and determining its life-cycle feasibility and superiority to alternative concepts.
Requirements: A complete, verified specification of the required functions, interfaces, and performance for the software product. Product
Design: A complete verified specification of the overall hardware-software architecture, control structure, and data structure for the product, along with such other necessary components as draft user's manuals and test plans.
Detailed Design: A complete verified specification of the control structure, data structure, interface relations, sizing, key algorithms, and assumptions of each program component.
Coding: A complete, verified set of program components. Integration: A properly function software product composed of the software components.
Implementation: A fully functioning operational hardware-software system, including such objectives as program and data conversion, installation, and training.
Maintenance: A fully functioning update of the hardware-software system repeated for each update.
Phaseout: A clean transition of the functions performed by the product to its successors.
Advantages
If in the beginning of the project failures are detected, it takes less effort (and therefore time and money) for this error. In the waterfall model phases to be properly sealed first before proceeding to the next stage. It is believed that the phases are correct before proceeding to the next phase. In the waterfall model lay the emphasis on documentation. In the newer software development methodologies makes it less documentation. This means that when new people in the project, and people leave it is difficult to transfer knowledge. This disadvantage is not the traditional waterfall model. It is a straightforward method. The way of working ensures that there are specific phases. This tells you what stage it is. One can use this method of milestones. Milestones can be used to monitor the progress of the project to estimate. The waterfall model is well known. Many people have experienced, so there might be easy to work. When frequent portions of the software product to be delivered this gives the customer confidence, but also the software development team.
Disadvantages
There are some disadvantages of this way to develop software. Many software projects are dependent on external factors. The client is a very important external factor. Often the requirements over the course of the project change, because the client wants something different. It is a disadvantage that the waterfall model assumes that the requirements will not change during the project. When a requirement changes in the construction phase, a substantial number of phases made again. It is very difficult to time and cost estimate. The phases are very large, it is therefore very difficult to estimate how much each step cost. In a number of new methods are almost all aspects of a software development process included. One can think of planning techniques, project management methods and how the project should be organized. In many software projects, different people at different stages of the project. For example: the designers and builders. They all have a different view of the project as designers look at the project differently than the builders. Conversely, the builders often different from the design of the designers look than the designers themselves. Frequently, the design will be adjusted again. Here is the waterfall model is not made for that. Within the project the team members often specialized. One team member will be only the first phase involved the design, while the only builders in construction helping to build the project. This can lead to waste of different sources. The main source is the time. An example: the designers are working on perfecting the design. The builders are in principle already start building, but because they work with the waterfall model, they should wait until the first phase is complete. This is a typical example of wasted time. Testing is done only in one of the last phases of the project. In many other software development methods will be tested once a certain part and finished product is at last an integration test. Because so much emphasis on documentation, the waterfall model is not efficient for smaller projects. There’s too much effort to the project itself around in terms of documentation.
Slide – 10
Advantages:
Risk reduction mechanisms are in place
Supports iteration and reflects real-world practices
Systematic approach
Disadvantages:
Requires expertise in risk evaluation and reduction
Complex, relatively difficult to follow strictly
Applicable only to large systems
Applicability:
Internal development of large systems

CSE 101 LECTURE 4

noreply@blogger.com (TANVIR) — Sat, 20 Aug 2011 14:38:00 +0600

FOR POWER POINT AND RELEVANT SLIDE MAIL ME AT tanvirfalcon@gmail.com
Slide-3
Simultaneous Access
• In organizations, many people may need to use the same data or programs. A network solves this problem.
• Shared data and programs can be stored on a central network server. A server that stores data files may be called a file server.
• Managers may assign access rights to users. Some users may only be able to read data, others may be able to make changes to existing files.
Shared Peripheral Devices
• Because peripheral (external) devices like printers can be expensive, it is cost-effective to connect a device to a network so users can share it.
• Through a process called spooling, users can send multiple documents (called print jobs) to a networked printer at the same time. The documents are temporarily stored on the server and printed in turn.
Personal Communication
• One of the most common uses of networks is for electronic mail (e-mail).
• An e-mail system enables users to exchange written messages (often with data files attached) across the local network or over the Internet.
• Two other popular network-based communications systems are teleconferencing and videoconferencing.
Easier Backup
• Networks enable managers to easily back up (make backup copies of) important data.
• Administrators commonly back up shared data files stored on the server, but may also use the network to back up files on users' PCs.
Slide-4
Server based networking
Server based networking provides a central location for management, backups, updates, anti-virus management, anti-spam management, and anti-spyware management. Server based networking can also provide you with monitoring of employee activities suchas internet usage, web pages viewed and instant messenger use.
• A network in which all client computers use a dedicated central server computer for network functions such as storage, security and other resources.
• A server has a large hard disk for shared storage. It may provide other services to the nodes, as well.
In a file server network, nodes can access files on the server, but not necessarily on other nodes.
mainframe
Mainframe computers are typically large, metal boxed computers with large processing abilities. The terminals are called "dumb terminals" because they only send and receive data, leaving the processing to the mainframe
Client / Server Network
The client/server refers to the way two computer programs interact with each other.
The client makes a request from the server, who then fulfills the request. Although this idea can be used on one computer it is an efficient way for a network of computers in different locations to interconnect.
Advantages
In most cases, a client-server architecture enables the roles and responsibilities of a computing system to be distributed among several independent computers that are known to each other only through a network. This creates an additional advantage to this architecture: greater ease of maintenance. For example, it is possible to replace, repair, upgrade, or even relocate a server while its clients remain both unaware and unaffected by that change. This independence from change is also referred to as encapsulation.
All the data is stored on the servers, which generally have far greater security controls than most clients. Servers can better control access and resources, to guarantee that only those clients with the appropriate permissions may access and change data.
Since data storage is centralized, updates to that data are far easier to administer than what would be possible under a P2P paradigm. Under a P2P architecture, data updates may need to be distributed and applied to each "peer" in the network, which is both time-consuming and error-prone, as there can be thousands or even millions of peers.
Many mature client-server technologies are already available which were designed to ensure security, 'friendliness' of the user interface, and ease of use.
It functions with multiple different clients of different capabilities.
Disadvantages
Traffic congestion on the network has been an issue since the inception of the client-server paradigm. As the number of simultaneous client requests to a given server increases, the server can become severely overloaded. Contrast that to a P2P network, where its bandwidth actually increases as more nodes are added, since the P2P network's overall bandwidth can be roughly computed as the sum of the bandwidths of every node in that network.
The client-server paradigm lacks the robustness of a good P2P network. Under client-server, should a critical server fail, clients’ requests cannot be fulfilled. In P2P networks, resources are usually distributed among many nodes. Even if one or more nodes depart and abandon a downloading file, for example, the remaining nodes should still have the data needed to complete the download.
Specific types of clients include web browsers, email clients, and online chat clients.
Specific types of servers include web servers, ftp servers, application servers, database servers, mail servers, file servers, print servers, and terminal servers. Most web services are also types of servers.
LANs
• LAN stands for Local Area Network.
• The first LANs were created in the late 1970s.
• LANs are small networks constricted to a small area like a house, office, or city.
• A LAN is a network whose computers are located relatively near one another.
• The nodes may be connected by a cable, infrared link, or small transmitters.
• A network transmits data among computers by breaking it into small pieces, called packets.
• Every LAN uses a protocol – a set of rules that governs how packets are configured and transmitted.
• LANs are used to share resources like storage, internet,etc.
• A 'node' on a LAN is a connected computer or device like a printer.
WANs
• WAN stands for Wide Area Network.
• WANs are very large networks that interconnect smaller LAN networks, for a large geographic area like a country(i.e., any network whose communications links cross metropolitan, regional, or national boundaries.) [9]
• WANs are usually for private companies, however, some built by internet service providers connect LANs to the internet.
• WAN can use a combination of satellites, microwave, and link and variety of computers from mainframes to terminals.
• A 'node' on a WAN is a LAN.
Personal Area Network (PAN)
A personal area network (PAN) is a computer network used for communication among computer devices.

PAN Usually, uses short range wireless technology is used to connect devises like a cell phone and a PDA.
Home Area Network (HAN)
HAN is short for Home Area Network. HAN is a recently coined term for a small LAN in a home environment, used for lifestyle purposes.
Home Area Network uses cable, wired, or wireless connections to connect a homes' digital devices. For example, fax machines, computers, DVD's etc.
Garden Area Network (GAN)
A similar system such as HAN would be GAN which stands for Garden Area Network, and allows for one system to control such devices like garden lights, sprinkler systems and alarm systems
Slide-8
In peer-to-peer networking there are no dedicated servers or hierarchy among the computers. All of the computers are equal and therefore known as peers. Normally each computer serves as Client/Server and there is no one assigned to be an administrator responsible for the entire network.

Peer-to-peer networks are good choices for needs of small organizations where the users are allocated in the same general area, security is not an issue and the organization and the network will have limited growth within the foreseeable future.

The term Client/server refers to the concept of sharing the work involved in processing data between the client computer and the most powerful server computer.
Slide-9
Network Interface Cards (NIC)
A network card, network adapter or NIC (network interface card) is a piece of computer hardware designed to allow computers to communicate over a computer network. It provides physical access to a networking medium and often provides a low-level addressing system through the use of MAC addresses. It allows users to connect to each other either by using cables or wirelessly.
Repeaters
A repeater is an electronic device that receives a signal and retransmits it at a higher power level, or to the other side of an obstruction, so that the signal can cover longer distances without degradation. In most twisted pair ethernet configurations, repeaters are required for cable runs longer than 100 meters away from the computer.
Hubs
A hub contains multiple ports. When a packet arrives at one port, it is copied to all the ports of the hub for transmission. When the packets are copied, the destination address in the frame does not change to a broadcast address. It does this in a rudimentary way, it simply copies the data to all of the Nodes connected to the hub.[3]
Bridges
A network bridge connects multiple network segments at the data link layer (layer 2) of the OSI model. Bridges do not promiscuously copy traffic to all ports, as hubs do, but learn which MAC addresses are reachable through specific ports. Once the bridge associates a port and an address, it will send traffic for that address only to that port. Bridges do send broadcasts to all ports except the one on which the broadcast was received.
Bridges learn the association of ports and addresses by examining the source address of frames that it sees on various ports. Once a frame arrives through a port, its source address is stored and the bridge assumes that MAC address is associated with that port. The first time that a previously unknown destination address is seen, the bridge will forward the frame to all ports other than the one on which the frame arrived.
Bridges come in three basic types:
Local bridges: Directly connect local area networks (LANs)
Remote bridges: Can be used to create a wide area network (WAN) link between LANs. Remote bridges, where the connecting link is slower than the end networks, largely have been replaced by routers.
Wireless bridges: Can be used to join LANs or connect remote stations to LANs.
Switches
A switch is a device that performs switching. Specifically, it forwards and filters OSI layer 2 datagrams (chunk of data communication) between ports (connected cables) based on the MAC addresses in the packets. This is distinct from a hub in that it only forwards the datagrams to the ports involved in the communications rather than all ports connected. Strictly speaking, a switch is not capable of routing traffic based on IP address (layer 3) which is necessary for communicating between network segments or within a large or complex LAN. Some switches are capable of routing based on IP addresses but are still called switches as a marketing term. A switch normally has numerous ports, with the intention being that most or all of the network is connected directly to the switch, or another switch that is in turn connected to a switch.
Switch is a marketing term that encompasses routers and bridges, as well as devices that may distribute traffic on load or by application content (e.g., a Web URL identifier). Switches may operate at one or more OSI model layers, including physical, data link, network, or transport (i.e., end-to-end). A device that operates simultaneously at more than one of these layers is called a multilayer switch.
Overemphasizing the ill-defined term "switch" often leads to confusion when first trying to understand networking. Many experienced network designers and operators recommend starting with the logic of devices dealing with only one protocol level, not all of which are covered by OSI. Multilayer device selection is an advanced topic that may lead to selecting particular implementations, but multilayer switching is simply not a real-world design concept.
Routers
Routers are networking devices that forward data packets between networks using headers and forwarding tables to determine the best path to forward the packets. Routers work at the network layer of the TCP/IP model or layer 3 of the OSI model. Routers also provide interconnectivity between like and unlike media (RFC 1812). This is accomplished by examining the Header of a data packet, and making a decision on the next hop to which it should be sent (RFC 1812) They use preconfigured static routes, status of their hardware interfaces, and routing protocols to select the best route between any two subnets. A router is connected to at least two networks, commonly two LANs or WANs or a LAN and its ISP's network. Some DSL and cable modems, for home (and even office) use, have been integrated with routers to allow multiple home/office computers to access the Internet through the same connection. Many of these new devices also consist of wireless access points (waps) or wireless routers to allow for IEEE 802.11b/g wireless enabled devices to connect to the network without the need for cabled connections.
Slide – 12
Intranet
An intranet is a set of networks, using the Internet Protocol and IP-based tools such as web browsers and file transfer applications, that is under the control of a single administrative entity. That administrative entity closes the intranet to all but specific, authorized users. Most commonly, an intranet is the internal network of an organization. A large intranet will typically have at least one web server to provide users with organizational information.
Extranet
An extranet is a network or internetwork that is limited in scope to a single organization or entity but which also has limited connections to the networks of one or more other usually, but not necessarily, trusted organizations or entities (e.g. a company's customers may be given access to some part of its intranet creating in this way an extranet, while at the same time the customers may not be considered 'trusted' from a security standpoint). Technically, an extranet may also be categorized as a CAN, MAN, WAN, or other type of network, although, by definition, an extranet cannot consist of a single LAN; it must have at least one connection with an external network.
INTERNET
• The Internet was created by the Advanced Research Projects Agency (ARPA) and the U.S. Department of Defense for scientific and military communications.
• The Internet is a network of interconnected networks. Even if part of its infrastructure was destroyed, data could flow through the remaining networks.
• The Internet uses high-speed data lines, called backbones, to carry data. Smaller networks connect to the backbone, enabling any user on any network to exchange data with any other user.
The Internet is a worldwide, publicly accessible series of interconnected computer networks that transmit data by packet switching using the standard Internet Protocol. It is a "network of networks" that consists of millions of smaller networks, which together carry various information and services, such as electronic mail, online chat, file transfer, and the interlinked web pages and other resources of the World Wide Web (WWW). So the Internet is a collection of interconnected computer networks, linked by copper wires, fiber-optic cables, wireless connections, etc. In contrast, the Web is a collection of interconnected documents and other resources, linked by hyperlinks and URLs. The World Wide Web is one of the services accessible via the Internet, along with various others including e-mail, file sharing, online gaming and others.
Common uses
E-mail
The concept of sending electronic text messages between parties in a way analogous to mailing letters or memos predates the creation of the Internet. Even today it can be important to distinguish between Internet and internal e-mail systems. Internet e-mail may travel and be stored unencrypted on many other networks and machines out of both the sender's and the recipient's control. During this time it is quite possible for the content to be read and even tampered with by third parties, if anyone considers it important enough. Purely internal or intranet mail systems, where the information never leaves the corporate or organization's network, are much more secure, although in any organization there will be IT and other personnel whose job may involve monitoring, and occasionally accessing, the e-mail of other employees not addressed to them.
The World Wide Web
Many people use the terms Internet and World Wide Web (or just the Web) interchangeably, but, as discussed above, the two terms are not synonymous.
The World Wide Web is a huge set of interlinked documents, images and other resources, linked by hyperlinks and URLs. These hyperlinks and URLs allow the web servers and other machines that store originals, and cached copies, of these resources to deliver them as required using HTTP (Hypertext Transfer Protocol). HTTP is only one of the communication protocols used on the Internet.
Web services also use HTTP to allow software systems to communicate in order to share and exchange business logic and data.
Software products that can access the resources of the Web are correctly termed user agents. In normal use, web browsers, such as Internet Explorer and Firefox, access web pages and allow users to navigate from one to another via hyperlinks. Web documents may contain almost any combination of computer data including graphics, sounds, text, video, multimedia and interactive content including games, office applications and scientific demonstrations.
Using the Web, it is also easier than ever before for individuals and organisations to publish ideas and information to an extremely large audience. Anyone can find ways to publish a web page, a blog or build a website for very little initial cost. Publishing and maintaining large, professional websites full of attractive, diverse and up-to-date information is still a difficult and expensive proposition, however.
Many individuals and some companies and groups use "web logs" or blogs, which are largely used as easily updatable online diaries. Some commercial organisations encourage staff to fill them with advice on their areas of specialization in the hope that visitors will be impressed by the expert knowledge and free information, and be attracted to the corporation as a result. One example of this practice is Microsoft, whose product developers publish their personal blogs in order to pique the public's interest in their work.

Remote access
The Internet allows computer users to connect to other computers and information stores easily, wherever they may be across the world. They may do this with or without the use of security, authentication and encryption technologies, depending on the requirements.
This is encouraging new ways of working from home, collaboration and information sharing in many industries. An accountant sitting at home can audit the books of a company based in another country, on a server situated in a third country that is remotely maintained by IT specialists in a fourth. These accounts could have been created by home-working bookkeepers, in other remote locations, based on information e-mailed to them from offices all over the world. Some of these things were possible before the widespread use of the Internet, but the cost of private leased lines would have made many of them infeasible in practice.
An office worker away from his desk, perhaps on the other side of the world on a business trip or a holiday, can open a remote desktop session into his normal office PC using a secure Virtual Private Network (VPN) connection via the Internet. This gives the worker complete access to all of his or her normal files and data, including e-mail and other applications, while away from the office.
This concept is also referred to by some network security people as the Virtual Private Nightmare, because it extends the secure perimeter of a corporate network into its employees' homes; this has been the source of some notable security breaches, but also provides security for the workers.
Collaboration
The low cost and nearly instantaneous sharing of ideas, knowledge, and skills has made collaborative work dramatically easier. Not only can a group cheaply communicate and test, but the wide reach of the Internet allows such groups to easily form in the first place, even among niche interests. An example of this is the free software movement in software development, which produced GNU and Linux from scratch and has taken over development of Mozilla and OpenOffice.org (formerly known as Netscape Communicator and StarOffice).
Internet "chat", whether in the form of IRC "chat rooms" or channels, or via instant messaging systems, allow colleagues to stay in touch in a very convenient way when working at their computers during the day. Messages can be sent and viewed even more quickly and conveniently than via e-mail. Extension to these systems may allow files to be exchanged, "whiteboard" drawings to be shared as well as voice and video contact between team members.
Version control systems allow collaborating teams to work on shared sets of documents without either accidentally overwriting each other's work or having members wait until they get "sent" documents to be able to add their thoughts and changes.
File sharing
A computer file can be e-mailed to customers, colleagues and friends as an attachment. It can be uploaded to a website or FTP server for easy download by others. It can be put into a "shared location" or onto a file server for instant use by colleagues. The load of bulk downloads to many users can be eased by the use of "mirror" servers or peer-to-peer networks.
In any of these cases, access to the file may be controlled by user authentication; the transit of the file over the Internet may be obscured by encryption, and money may change hands before or after access to the file is given. The price can be paid by the remote charging of funds from, for example, a credit card whose details are also passed—hopefully fully encrypted—across the Internet. The origin and authenticity of the file received may be checked by digital signatures or by MD5 or other message digests.
These simple features of the Internet, over a worldwide basis, are changing the basis for the production, sale, and distribution of anything that can be reduced to a computer file for transmission. This includes all manner of print publications, software products, news, music, film, video, photography, graphics and the other arts. This in turn has caused seismic shifts in each of the existing industries that previously controlled the production and distribution of these products.
Internet collaboration technology enables business and project teams to share documents, calendars and other information. Such collaboration occurs in a wide variety of areas including scientific research, software development, conference planning, political activism and creative writing.
Streaming media
Many existing radio and television broadcasters provide Internet "feeds" of their live audio and video streams (for example, the BBC). They may also allow time-shift viewing or listening such as Preview, Classic Clips and Listen Again features. These providers have been joined by a range of pure Internet "broadcasters" who never had on-air licenses. This means that an Internet-connected device, such as a computer or something more specific, can be used to access on-line media in much the same way as was previously possible only with a television or radio receiver. The range of material is much wider, from pornography to highly specialized, technical webcasts. Podcasting is a variation on this theme, where—usually audio—material is first downloaded in full and then may be played back on a computer or shifted to a digital audio player to be listened to on the move. These techniques using simple equipment allow anybody, with little censorship or licensing control, to broadcast audio-visual material on a worldwide basis.
Webcams can be seen as an even lower-budget extension of this phenomenon. While some webcams can give full-frame-rate video, the picture is usually either small or updates slowly. Internet users can watch animals around an African waterhole, ships in the Panama Canal, the traffic at a local roundabout or their own premises, live and in real time. Video chat rooms, video conferencing, and remote controllable webcams are also popular. Many uses can be found for personal webcams in and around the home, with and without two-way sound.
YouTube, sometimes described as an Internet phenomenon because of the vast amount of users and how rapidly the site's popularity has grown, was founded on February 15, 2005. It is now the leading website for free streaming video. It uses a flash-based web player which streams video files in the format FLV. Users are able to watch videos without signing up; however, if users do sign up they are able to upload an unlimited amount of videos and they are given their own personal profile. It is currently estimated that there are 64,000,000 videos on YouTube, and it is also currently estimated that 825,000 new videos are uploaded every day.
Voice telephony (VoIP)
VoIP stands for Voice over IP, where IP refers to the Internet Protocol that underlies all Internet communication. This phenomenon began as an optional two-way voice extension to some of the instant messaging systems that took off around the year 2000. In recent years many VoIP systems have become as easy to use and as convenient as a normal telephone. The benefit is that, as the Internet carries the actual voice traffic, VoIP can be free or cost much less than a normal telephone call, especially over long distances and especially for those with always-on Internet connections such as cable or ADSL.
Thus, VoIP is maturing into a viable alternative to traditional telephones. Interoperability between different providers has improved and the ability to call or receive a call from a traditional telephone is available. Simple, inexpensive VoIP modems are now available that eliminate the need for a PC.
Voice quality can still vary from call to call but is often equal to and can even exceed that of traditional calls.
Remaining problems for VoIP include emergency telephone number dialing and reliability. Currently, a few VoIP providers provide an emergency service, but it is not universally available. Traditional phones are line-powered and operate during a power failure; VoIP does not do so without a backup power source for the electronics.
Most VoIP providers offer unlimited national calling, but the direction in VoIP is clearly toward global coverage with unlimited minutes for a low monthly fee.
VoIP has also become increasingly popular within the gaming world, as a form of communication between players. Popular gaming VoIP clients include Ventrilo and Teamspeak, and there are others available also. The PlayStation 3 and Xbox 360 also offer VoIP chat features.
Slide -13
Network Topology Network topology are the physical layout of the network that the locations of the computers and how the cable is run between them. It is important to use the right topology. Each topology has its own strengths and weakness
Mesh Topology
• It is also called a point-to-point topology.
• Each device is connected directly to all other network devices.
• In a mesh topology, every device in the network is physically connected to every other device in the network. A message can be sent on different possible paths from source to destination. Mesh topology provides improved performance and reliability. Mesh networks are not used much in local area networks. It is mostly used in wide area networks.
Advantages
The use of dedicated link guarantees that each connection can carry its own data load. It eliminates traffic problem.
If one link becomes unusable, it does not harm the entire system.
It is easy to troubleshoot.
Disadvantages
A full mesh network can be very expensive.
It is difficult to install and reconfigure.
Bus Topology
• It is a multipoint topology.
• Each device shares the connection.
• Only one device at a time can send.
• Bus topology is the cheapest way of connecting computers to form a workgroup or departmental LAN, but it has the disadvantage that a single loose connection or cable break can bring down the entire LAN
Termination is important issue in bus networks. The electrical signal from a transmitting computer is free to travel the entire length of the cable. Without the termination, when the signal reaches the end of the wire, it bounces back and travels back up the wire. When a signal echoes back and forth along an unterminated bus, it is called ringing. The terminators absorb the electrical energy and stop the reflections.
Advantages:
Bus is easy to use and understand and inexpensive simple network
It is easy to extend a network by adding cable with a repeater that boosts the signal and allows it to travel a longer distance.
Disadvantage:
A bus topology becomes slow by heavy network traffic with a lot of computer because networks do not coordinate with each other to reserve times to transmit.
It is difficult to troubleshoot a bus because a cable break or loose connector will cause reflections and bring down the whole network.
Ring Topology
• It is a circle with no ends.
• Packets are sent from one device to the next
Advantages :
One computer cannot monopolize the network.
It continue to function after capacity is exceeded but the speed will be slow.
Disadvantages :
Failure of one computer can affect the whole network.
It is difficult to troubleshoot.
Adding and removing computers disrupts the network.
Star topology
• All devices are connected to a central device.
• The hub receives and forwards packets.
Advantages :
The failure of a single computer or cable doesn't bring down the entire network.
The centralized networking equipment can reduce costs in the long run by making network management much easier.
It allows several cable types in same network with a hub that can accommodate multiple cable types.
Disadvantages :
Failure of the central hub causes the whole network failure.
It is slightly more expensive than using bus topology.
Hybrid Topology
• Variations of two or more topologies.
• Star and Bus
• Star and Ring
Slide-15
Collection of interrelated data
Set of programs to access the data
DMBS contains information about a particular enterprise
DBMS provides an environment that it both convenient and efficient to use
Physical level: describes how a record (e.g. customer) is stored.
Logical level: describes data stored in database, and the relationships among the data.
type customer = record
name: string;
street: string;
city: integer;
end;
View level: application programs hide details of data types. Views can also hide information (e.g. salary) for security purposes.
Slide-16
A schema is the overall design of the database. It describes the data contents, structure and some other aspects of the database also called the intension of the database
The instance is the collection of data stored in the database at a particular time, also called the extension of the database.
Slide-17
A transaction is a collection of operations that performs a single logical function in a database application.
Transaction-management component ensures that the database remains in a consistent (correct) state despite system failures (e.g. power failures and operating system crashes) and transaction failures.
Concurrency-control manager controls the interaction among the concurrent transactions, to ensure the consistency of the database.
A storage manager is a program module that provides the interface between the low-level data stored in the database and the application programs and queries submitted to the system.
The storage manager is responsible for the following tasks:
Interaction with the file manager
Efficient storing, retrieving, and updating of data
Slide- 18
Users are differentiated by the way they expect to interact with
the system
• Application programmers – interact with system through DML calls
• Sophisticated users – form requests in a database query language
• Specialized users – write specialized database applications that do not fit into the traditional data processing framework
• Naïve users – invoke one of the permanent application programs that have been written previously
– Examples, people accessing database over the web, bank tellers, clerical staff
Slide-20
File System Data Management
Requires extensive programming in third-generation language (3GL)
Time consuming
Makes ad hoc queries impossible
Leads to islands of information
Data Dependence
Change in file’s data characteristics requires modification of data access programs
Must tell program what to do and how
Makes file systems cumbersome from programming and data management views
Structural Dependence
Change in file structure requires modification of related programs
Field Definitions and Naming Conventions
Flexible record definition anticipates reporting requirements
Selection of proper field names important
Attention to length of field names
Use of unique record identifiers
Data Redundancy
Different and conflicting versions of same data
Results of uncontrolled data redundancy
Data anomalies
Modification
Insertion
Deletion
Data inconsistency
Lack of data integrity
A good DBMS performs the following functions
maintain data dictionary
support multiple views of data
enforce integrity constraints
enforce access constraints
support concurrency control
support backup and recovery procedures
support logical transactions
Purpose of Database System
Built on top of file systems
Drawbacks of using file systems:
Atomicity of updates
Concurrent access by multiple users
Security problems
Database systems offer solutions to all the above problems
Slide -21
E-R model of real world
Entities (objects)
E.g. customers, accounts, bank branch
Relationships between entities
E.g. Account A-101 is held by customer Johnson
Relationship set depositor associates customers with accounts
Widely used for database design
Database design in E-R model usually converted to design in the relational model (coming up next) which is used for storage and processing

CSE 101 LECTURE 2

noreply@blogger.com (TANVIR) — Sat, 20 Aug 2011 14:34:00 +0600

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SLIDE-4
KeyBoard:
In computing, a keyboard is an input device partially modeled after the typewriter keyboard which uses an arrangement of buttons, or keys which act as electronic switches. A keyboard typically has characters engraved or printed on the keys, and each press of a key typically corresponds to a single written symbol. However, to produce some symbols requires pressing and holding several keys simultaneously or in sequence. While most keyboard keys produce letters, numbers or signs (characters), other keys or simultaneous key presses can produce actions or computer commands.
SLIDE- 6
Mouse
An input device that allows an individual to control a mouse pointer in a graphical user interface (GUI). Utilizing a mouse a user has the ability to perform various functions such as opening a program or file and does not require the user to memorize commands, like those used in a text-based environment such as MS-DOS.
When and who invented the first computer mouse?
The computer mouse as we know it today was invented and developed by Douglas Englebart during the 60's and was patented on November 17, 1970. While creating the mouse Douglas was working at the Stanford Research Institute, a think tank sponsored by Stanford University and originally referred to the mouse as a "X-Y Position Indicator for a Display System." This mouse was first used with the Xerox Alto computer system in 1973. However, because of its lack of success the first widely used mouse is credited to being the mouse found on the Apple Lisa computer. Today, the mouse is now found and used on every computer.
The above picture taken by Maracin Wichary at the New Mexico Museum of Natural History and Science is an example of what the first computer mouse looked liked. As can be seen by the picture the mouse was much larger than today's mouse, square, and had a small button in the top right corner.

World First Trackball Mouse
The world's first trackball invented by Tom Cranston, Fred Longstaff and Kenyon Taylor working on the Royal Canadian Navy's DATAR project in 1952. It used a standard Canadian five-pin bowling ball. It was not patented, as it was a secret military project.
Using the mouse involve five techniques.
1. Pointing; Move the mouse to move the on-screen pointer.
2. Clicking; Press and release the left mouse button once.
3. Double-clicking; Press and release the left mouse button twice.
4. Dragging; Hold down the left mouse button as you move the pointer.
5. Right-clicking; Press and release the right mouse button.

Trackballs
• A trackball is like a mouse turned upside-down.
• Use your thumb to move the exposed ball and your fingers to press the buttons.

Trackpads
• A track pad is a touch-sensitive pad that provides the same functionality as a mouse.
• To use a track pad, you glide your finger across its surface.
• Track pads provide a set of buttons that function like mouse buttons.

Integrated pointed Devices
• An integrated pointing device is a small joystick built into the keyboard.
• To use an integrated pointing device, you move the joystick.
• These devices provide a set of buttons that function like mouse buttons
SLIDE- 7
Digital Camera
A type of camera that stores the pictures or video it takes in electronic format instead of to film. There are several features that make digital cameras a popular choice when compared to film cameras. First, the feature often enjoyed the most is the LCD display on the digital camera. This display allows users to view photos or video after the picture or video has been taken, which means if you take a picture and don't like the results, you can delete it; or if you do like the picture, you can easily show it to other people. Another nice feature with digital cameras is the ability to take dozens, sometimes hundreds of different pictures. To the right is a picture of the Casio QV-R62, a 6.0 Mega Pixel digital camera used to help illustrate what a digital camera may look like.
Digital cameras have quickly become the camera solution for most users today as the quality of picture they take has greatly improved and as the price has decreased. Many users however are hesitant in buying a digital camera because of the inability of getting their pictures developed. However, there are several solutions in getting your digital pictures developed. For example, there are numerous Internet companies capable of developing your pictures and send you your pictures in the mail. In addition, many of the places that develop your standard cameras film now have the ability to develop digital pictures if you bring them your camera, memory stick, and/or pictures on CD.

SLIDE- 9
A touchscreen is a display which can detect the presence and location of a touch within the display area. The term generally refers to touch or contact to the display of the device by a finger or hand. Touchscreens can also sense other passive objects, such as a stylus. However, if the object sensed is active, as with a light pen, the term touchscreen is generally not applicable. The thumb rule is: if you can interact with the display using your finger, it is likely a touchscreen - even if you are using a stylus or some other object.
Up until recently, most touchscreens could only sense one point of contact at a time, and few have had the capability to sense how hard one is touching. This is starting to change with the emergence of multi-touch technology - a technology that was first seen in the early 1980s, but which is now appearing in commercially available systems.
The touchscreen has two main attributes. First, it enables you to interact with what is displayed directly on the screen, where it is displayed, rather than indirectly with a mouse (computing) or touchpad. Secondly, it lets one do so without requiring any intermediate device, again, such as a stylus that needs to be held in the hand. Such displays can be attached to computers or, as terminals, to networks. They also play a prominent role in the design of digital appliances such as the personal digital assistant (PDA), satellite navigation devices and mobile phone
SLIDE- 10
Monitor
1. Also called a video display terminal (VDT) a monitor is a video display screen and the hard shell that holds it. In its most common usage, monitor refers only to devices that contain no electronic equipment other than what is essentially needed to display and adjust the characteristics of an image.
SLIDE- 11
CRT Monitors
Sort for cathode-ray tubes, CRT monitors were the only choice consumers had for monitor technology for many years. Cathode ray tube (CRT) technology has been in use for more than 100 years, and is found in most televisions and computer monitors. A CRT

CSE 101 LECTURE 1

noreply@blogger.com (TANVIR) — Sat, 20 Aug 2011 14:27:00 +0600

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CSE 101 LECTURE 1 SLIDE 9
User Interface
The User interface is what you see when you turn on the computer. It Consists of the cursors, prompts, icons, menus, etc

Operating system provides these facilities for the user:
Program creation : editors, debuggers, other development tools.
Program execution : load, files, IO operations.
Access to IO devices: Read and writes.
Controlled access to files: protection mechanisms, abstraction of underlying device.
System access: Controls who can access the system.
Error detection and response: external, internal, software or hardware error.
Accounting: Collect stats., load sharing , for billing purposes.
Resource Management
Processors : Allocation of processes to processors, preemption, scheduling.
Memory: Allocation of main memory.
IO devices : when to access io devices, which ones etc.
Files: Partitions, space allocation and maintenance.
Applications, Data, objects.
Task Management
• The OS uses interrupt requests (IRQs) to maintain organized communication with the CPU and other pieces of hardware.
• Each hardware device is controlled by a piece of software, called a driver, which allows the OS to activate and use the device.
• The operating system provides the software necessary to link computers and form a network.
File Management
• The operating system keeps track of all the files on each disk.
• Users can make file management easier by creating a hierarchical file system that includes folders and subfolders arranged in a logical order.
Security
 When sharing resources, protection of the systems and user resources from intentional as well as inadvertent misuse.
 Protection generally deals with access control. Ex: Read only file
 Security deals usually with threats from outside the system that affects the integrity and availability of the system and information with the system.
 Example: username, password to access system. Data encryption to protect information.
Utilities
 A utility is a program that performs a task that is not typically handled by the operating system.
 Some utilities enhance the operating system's functionality.
 Some of the major categories of utilities include:
• File defragmentation
• Data compression
• Backup
• Antivirus
• Screen savers

Slide 10
Command Driven Interface
With a command-driven interface, you type in an instruction which is usually abbreviated, in order to get something done. Command Driven user interface is are not easy to use. If you are new to the software then you have to remember many commands in order to be able to use the software quickly.
 Some older operating systems, such as DOS and UNIX, use command-line interfaces.
 In a command-line interface, you type commands at a prompt.
 Under command-line interfaces, individual applications do not need to look or function the same way, so different programs can look very different
Menu Driven Interface
This type of user interface produce a list of commands or options available within a program and the user can make a selection by useing either a mouse or a keyboard. Bothe MS Windows and Machintosh programs are menu driven.
Graphical User Interface:
 Most modern operating systems, like Windows and the Macintosh OS, provide a graphical user interface (GUI).
 A GUI lets you control the system by using a mouse to click graphical objects on screen.
 A GUI is based on the desktop metaphor. Graphical objects appear on a background (the desktop), representing resources you can use.
SLIDE 11
GUI Tools
 Icons are pictures that represent computer resources, such as printers, documents, and programs.
 You double-click an icon to choose (activate) it, for instance, to launch a program.
 The Windows operating system offers two unique tools, called the taskbar and Start button. These help you run and manage programs.
Applications and the Interface
 Applications designed to run under one operating system use similar interface elements.
 Under an OS such as Windows, you see a familiar interface no matter what programs you use.
 In a GUI, each program opens and runs in a separate window—a frame that presents the program and its documents.
 In a GUI, you can run multiple programs at once, each in a separate window. The application in use is said to be the active window.
Menus
 GUI-based programs let you issue commands by choosing them from menus.
 A menu groups related commands. For example, the File menu's commands let you open, save, and print document files.
 Menus let you avoid memorizing and typing command names.
 In programs designed for the same GUI, menus and commands are similar from one program to another
Dialoge Box
 A dialog box is a special window that appears when a program or the OS needs more information before completing a task.
 Dialog boxes are so named because they conduct a "dialog" with the user, asking the user to provide more information or make choices.
WIMP
WIMP stands for windows, icons, menus and pointing devices. The term describes the features of a graphical user interface which make it easier for the user to get things done.

SLIDE-13
Basic Services
• The operating system manages all the other programs that run on the PC.
• The operating system provides services to programs and the user, including file management, memory management, and printing
• To provide services to programs, the OS makes system calls—requesting other hardware and software resources to perform tasks.
Sharing Information
• Some operating systems, such as Windows, enable programs to share information.
• You can create data in one program and use it again in other programs without re-creating it.
• Windows provides the Clipboard, a special area that stores data cut or copied from one document, so you can re-use it elsewhere.
Multi-tasking
• Multitasking is the capability of running multiple processes simultaneously.
• A multitasking OS lets you run multiple programs at the same time.
• Through multitasking, you can do several chores at one time, such as printing a document while downloading a file from the Internet.
• There are two types of multitasking: cooperative and preemptive.
Slid-14
System Software :
System Software refers to the operating system and all utility programs that manage computer resources at a low level. Systems software includes compilers, loaders, linkers, and debuggers.
System Software can be devided in major 3 criteria
1. System Management Program
2. System Support Program
3. System Development Program
System Management Program
1. Operating System
2. Network Management
3. Device Driver
System Sopport Program
1. System Utility Program
2. System Performance monitor program
3. System Security Monitor Program
System Development Program
1. Programming Language Translator
2. Programming editor and tools
3. Computer Aided Software Engineering (CASE)
Application Software
Applications software comprises programs designed for an end user, such as word processors, database systems, and spreadsheet programs.
Application Software can be divided in major criteria
General Application Program
Specific Application Program
General Application Program
Some of the General Application Program are
Software Suite – MS Office, Lotus smart Suit, Coral Word Perfect Office
Web Browser – Internet Explorer, Netscape, Opera.
Electronic Mail - e-mail, Eudora, etc
Desktop publishing - Page maker, Publisher
Database Management System – Oracle, Access, dBase
Specific Application Program
Some of the Specific Application Program are: Accounting Software, Sales Management, E-commerce, Inventory control, Pay roll system, Ticket reservation, etc
SLIDE-24
Concise industry history of Supercomputer
Supercomputers introduced in the 1960s were designed primarily by Seymour Cray at Control Data Corporation (CDC), and led the market into the 1970s until Cray left to form his own company, Cray Research. He then took over the supercomputer market with his new designs, holding the top spot in supercomputing for 5 years (1985–1990). Cray, himself, never used the word "supercomputer," a little-remembered fact in that he only recognized the word "computer." In the 1980s a large number of smaller competitors entered the market, in a parallel to the creation of the minicomputer market a decade earlier, but many of these disappeared in the mid-1990s "supercomputer market crash". Today, supercomputers are typically one-of-a-kind custom designs produced by "traditional" companies such as IBM and HP, who had purchased many of the 1980s companies to gain their experience, although Cray Inc. still specializes in building supercomputers.
The Cray-2 was the world's fastest computer from 1985 to 1989.
The term supercomputer itself is rather fluid, and today's supercomputer tends to become tomorrow's normal computer. CDC's early machines were simply very fast scalar processors, some ten times the speed of the fastest machines offered by other companies. In the 1970s most supercomputers were dedicated to running a vector processor, and many of the newer players developed their own such processors at a lower price to enter the market. The early and mid-1980s saw machines with a modest number of vector processors working in parallel become the standard. Typical numbers of processors were in the range 4–16. In the later 1980s and 1990s, attention turned from vector processors to massive parallel processing systems with thousands of "ordinary" CPUs, some being off the shelf units and others being custom designs. (This is commonly and humorously referred to as the attack of the killer micros in the industry.) Today, parallel designs are based on "off the shelf" server-class microprocessors, such as the PowerPC, Itanium, or x86-64, and most modern supercomputers are now highly-tuned computer clusters using commodity processors combined with custom interconnects.
Software tools
Software tools for distributed processing include standard APIs such as MPI and PVM, and open source-based software solutions such as Beowulf and openMosix which facilitate the creation of a supercomputer from a collection of ordinary workstations or servers. Technology like ZeroConf (Rendezvous/Bonjour) can be used to create ad hoc computer clusters for specialized software such as Apple's Shake compositing application. An easy programming language for supercomputers remains an open research topic in computer science.
Common uses
Supercomputers are used for highly calculation-intensive tasks such as problems involving quantum mechanical physics, weather forecasting, climate research (including research into global warming), molecular modeling (computing the structures and properties of chemical compounds, biological macromolecules, polymers, and crystals), physical simulations (such as simulation of airplanes in wind tunnels, simulation of the detonation of nuclear weapons, and research into nuclear fusion), cryptanalysis, and the like. Major universities, military agencies and scientific research laboratories are heavy users.
A particular class of problems, known as Grand Challenge problems, are problems whose full solution requires semi-infinite computing resources.
Relevant here is the distinction between capability computing and capacity computing, as defined by Graham et al. Capability computing is typically thought of as using the maximum computing power to solve a large problem in the shortest amount of time. Oftentimes a capability system is able to solve a problem of a size or complexity that no other computer can. Capacity computing in contrast is typically thought of as using efficient cost-effective computing power to solve somewhat large problems or many small problems or to prepare for a run on a capability system.
Hardware and software design
Processor board of a CRAY YMP vector computer
Supercomputers using custom CPUs traditionally gained their speed over conventional computers through the use of innovative designs that allow them to perform many tasks in parallel, as well as complex detail engineering. They tend to be specialized for certain types of computation, usually numerical calculations, and perform poorly at more general computing tasks. Their memory hierarchy is very carefully designed to ensure the processor is kept fed with data and instructions at all times—in fact, much of the performance difference between slower computers and supercomputers is due to the memory hierarchy. Their I/O systems tend to be designed to support high bandwidth, with latency less of an issue, because supercomputers are not used for transaction processing.
As with all highly parallel systems, Amdahl's law applies, and supercomputer designs devote great effort to eliminating software serialization, and using hardware to accelerate the remaining bottlenecks.
Supercomputer challenges, technologies
A supercomputer generates large amounts of heat and must be cooled. Cooling most supercomputers is a major HVAC problem.
Information cannot move faster than the speed of light between two parts of a supercomputer. For this reason, a supercomputer that is many meters across must have latencies between its components measured at least in the tens of nanoseconds. Seymour Cray's supercomputer designs attempted to keep cable runs as short as possible for this reason: hence the cylindrical shape of his Cray range of computers. In modern supercomputers built of many conventional CPUs running in parallel, latencies of 1-5 microseconds to send a message between CPUs are typical.
Supercomputers consume and produce massive amounts of data in a very short period of time. According to Ken Batcher, "A supercomputer is a device for turning compute-bound problems into I/O-bound problems." Much work on external storage bandwidth is needed to ensure that this information can be transferred quickly and stored/retrieved correctly.
Technologies developed for supercomputers include:
Vector processing
Liquid cooling
Non-Uniform Memory Access (NUMA)
Striped disks (the first instance of what was later called RAID)
Parallel filesystems
Processing techniques
Vector processing techniques were first developed for supercomputers and continue to be used in specialist high-performance applications. Vector processing techniques have trickled down to the mass market in DSP architectures and SIMD processing instructions for general-purpose computers.
Modern video game consoles in particular use SIMD extensively and this is the basis for some manufacturers' claim that their game machines are themselves supercomputers. Indeed, some graphics cards have the computing power of several TeraFLOPS. The applications to which this power can be applied was limited by the special-purpose nature of early video processing. As video processing has become more sophisticated, Graphics processing units (GPUs) have evolved to become more useful as general-purpose vector processors, and an entire computer science sub-discipline has arisen to exploit this capability: General-Purpose Computing on Graphics Processing Units (GPGPU.)
Operating systems
Supercomputers predominantly run some variant of Linux or UNIX. Linux is the most popular since 2004
Supercomputer operating systems, today most often variants of Linux or UNIX, are every bit as complex as those for smaller machines, if not more so. Their user interfaces tend to be less developed, however, as the OS developers have limited programming resources to spend on non-essential parts of the OS (i.e., parts not directly contributing to the optimal utilization of the machine's hardware). This stems from the fact that because these computers, often priced at millions of dollars, are sold to a very small market, their R&D budgets are often limited. (The advent of Unix and Linux allows reuse of conventional desktop software and user interfaces.)
Interestingly this has been a continuing trend throughout the supercomputer industry, with former technology leaders such as Silicon Graphics taking a back seat to such companies as NVIDIA, who have been able to produce cheap, feature-rich, high-performance, and innovative products due to the vast number of consumers driving their R&D.
Historically, until the early-to-mid-1980s, supercomputers usually sacrificed instruction set compatibility and code portability for performance (processing and memory access speed). For the most part, supercomputers to this time (unlike high-end mainframes) had vastly different operating systems. The Cray-1 alone had at least six different proprietary OSs largely unknown to the general computing community. Similarly different and incompatible vectorizing and parallelizing compilers for Fortran existed. This trend would have continued with the ETA-10 were it not for the initial instruction set compatibility between the Cray-1 and the Cray X-MP, and the adoption of UNIX operating system variants (such as Cray's Unicos and today's Linux.)
For this reason, in the future, the highest performance systems are likely to have a UNIX flavor but with incompatible system-unique features (especially for the highest-end systems at secure facilities).
Programming
The parallel architectures of supercomputers often dictate the use of special programming techniques to exploit their speed. Special-purpose Fortran compilers can often generate faster code than C or C++ compilers, so Fortran remains the language of choice for scientific programming, and hence for most programs run on supercomputers. To exploit the parallelism of supercomputers, programming environments such as PVM and MPI for loosely connected clusters and OpenMP for tightly coordinated shared memory machines are being used.
Modern supercomputer architecture
The Columbia Supercomputer at NASA's Advanced Supercomputing Facility at Ames Research Center
As of November 2006, the top ten supercomputers on the Top500 list (and indeed the bulk of the remainder of the list) have the same top-level architecture. Each of them is a cluster of MIMD multiprocessors, each processor of which is SIMD. The supercomputers vary radically with respect to the number of multiprocessors per cluster, the number of processors per multiprocessor, and the number of simultaneous instructions per SIMD processor. Within this hierarchy we have:
A computer cluster is a collection of computers that are highly interconnected via a high-speed network or switching fabric. Each computer runs under a separate instance of an Operating System (OS).
A multiprocessing computer is a computer, operating under a single OS and using more than one CPU, where the application-level software is indifferent to the number of processors. The processors share tasks using Symmetric multiprocessing(SMP) and Non-Uniform Memory Access(NUMA).
An SIMD processor executes the same instruction on more than one set of data at the same time. The processor could be a general purpose commodity processor or special-purpose vector processor. It could also be high performance processor or a low power processor.
As of November 2006, the fastest machine is Blue Gene/L. This machine is a cluster of 65,536 computers, each with two processors, each of which processes two data streams concurrently. By contrast, Columbia is a cluster of 20 machines, each with 512 processors, each of which processes two data streams concurrently.
As of 2005, Moore's Law and economies of scale are the dominant factors in supercomputer design: a single modern desktop PC is now more powerful than a 15-year old supercomputer, and the design concepts that allowed past supercomputers to out-perform contemporaneous desktop machines have now been incorporated into commodity PCs. Furthermore, the costs of chip development and production make it uneconomical to design custom chips for a small run and favor mass-produced chips that have enough demand to recoup the cost of production. A current model quad core Xeon workstation running at 2.66Ghz will outperform a multimillion dollar cray C90 supercomputer used in the early 1990s, lots of workloads requiring such a supercomputer in the 1990s can now be done on workstations costing less than 4000 US dollars.
Additionally, many problems carried out by supercomputers are particularly suitable for parallelization (in essence, splitting up into smaller parts to be worked on simultaneously) and, particularly, fairly coarse-grained parallelization that limits the amount of information that needs to be transferred between independent processing units. For this reason, traditional supercomputers can be replaced, for many applications, by "clusters" of computers of standard design which can be programmed to act as one large computer.
Special-purpose supercomputers
Special-purpose supercomputers are high-performance computing devices with a hardware architecture dedicated to a single problem. This allows the use of specially programmed FPGA chips or even custom VLSI chips, allowing higher price/performance ratios by sacrificing generality. They are used for applications such as astrophysics computation and brute-force codebreaking. Historically a new special-purpose supercomputer has occasionally been faster than the world's fastest general-purpose supercomputer, by some measure. For example, GRAPE-6 was faster than the Earth Simulator in 2002 for a particular special set of problems.
Examples of special-purpose supercomputers:
Deep Blue, for playing chess
Reconfigurable computing machines or parts of machines
GRAPE, for astrophysics and molecular dynamics
Deep Crack, for breaking the DES cipher
The fastest supercomputers today
Measuring supercomputer speed
The speed of a supercomputer is generally measured in "FLOPS" (FLoating Point Operations Per Second), commonly used with an SI prefix such as tera-, combined into the shorthand "TFLOPS" (1012 FLOPS, pronounced teraflops), or peta-,combined into the shorthand "PFLOPS" (1015 FLOPS, pronounced petaflops.) This measurement is based on a particular benchmark which does LU decomposition of a large matrix. This mimics a class of real-world problems, but is significantly easier to compute than a majority of actual real-world problems.
Current fastest supercomputer system
Roadrunner is a supercomputer built by IBM at the Los Alamos National Laboratory in New Mexico, USA. Currently the world's fastest computer, Price - US$133-million = TK 919,99,99,977.00
Courtesy: Wikipedia.com
SLIDE-27
Mainframes (often colloquially referred to as Big Iron) are computers used mainly by large organizations for critical applications, typically bulk data processing such as census, industry and consumer statistics, ERP, and financial transaction processing.
The term probably originated from the early mainframes, as they were housed in enormous, room-sized metal boxes or frames. [1] Later the term was used to distinguish high-end commercial machines from less powerful units which were often contained in smaller packages.
Today in practice, the term usually refers to computers compatible with the IBM System/360 line, first introduced in 1965. (IBM System z9 is IBM's latest incarnation.) Otherwise, systems with similar functionality but not based on the IBM System/360 are referred to as "servers." However, "server" and "mainframe" are not synonymous (see client-server).
Some non-System/360-compatible systems derived from or compatible with older (pre-Web) server technology may also be considered mainframes. These include the Burroughs large systems and the UNIVAC 1100/2200 series systems. Most large-scale computer system architectures were firmly established in the 1960s and most large computers were based on architecture established during that era up until the advent of Web servers in the 1990s. (Interestingly, the first Web server running anywhere outside Switzerland ran on an IBM mainframe at Stanford University as early as 1990. See History of the World Wide Web for details.)
There were several minicomputer operating systems and architectures that arose in the 1970s and 1980s, but minicomputers are generally not considered mainframes. (UNIX arose as a minicomputer operating system; Unix has scaled up over the years to acquire some mainframe characteristics.)
Many defining characteristics of "mainframe" were established in the 1960s, but those characteristics continue to expand and evolve to the present day.

Description
Modern mainframe computers have abilities not so much defined by their single task computational speed (flops or clock rate) as by their redundant internal engineering and resulting high reliability and security, extensive input-output facilities, strict backward compatibility for older software, and high utilization rates to support massive throughput. These machines often run for years without interruption, with repairs and even software and hardware upgrades taking place during normal operation. For example, ENIAC remained in continuous operation from 1947 to 1955. More recently, there are several IBM mainframe installations that have delivered over a decade of continuous business service as of 2007, with upgrades not interrupting service. Mainframes are defined by high availability, one of the main reasons for their longevity, as they are used in applications where downtime would be costly or catastrophic. The term Reliability, Availability and Serviceability (RAS) is a defining characteristic of mainframe computers.
In the 1960s, most mainframes had no interactive interface. They accepted sets of punch cards, paper tape, and/or magnetic tape and operated solely in batch mode to support back office functions, such as customer billing. Teletype devices were also common, at least for system operators. By the early 1970s, many mainframes acquired interactive user interfaces and operated as timesharing computers, supporting hundreds or thousands of users simultaneously along with batch processing. Users gained access through specialized terminals or, later, from personal computers equipped with terminal emulation software. Many mainframes supported graphical terminals (and terminal emulation) by the 1980s (if not earlier). Nowadays most mainframes have partially or entirely phased out classic user terminal access in favor of Web user interfaces.
Historically mainframes acquired their name in part because of their substantial size and requirements for specialized HVAC and electrical power. Those requirements ended by the mid-1990s, with CMOS mainframe designs replacing the older bipolar technology. In fact, in a major reversal, IBM touts the mainframe's ability to reduce data center energy costs for power and cooling and reduced physical space requirements compared to server farms.
Characteristics of mainframes
Nearly all mainframes have the ability to run (or "host") multiple operating systems and thereby operate not as a single computer but as a number of virtual machines. In this role, a single mainframe can replace dozens or even hundreds of smaller servers, reducing management and administrative costs while providing greatly improved scalability and reliability.
Mainframes can add system capacity nondisruptively and granularly. Modern mainframes, notably the IBM zSeries and System z9 servers, offer three levels of virtualization: logical partitions (LPARs, via the PR/SM facility), virtual machines (via the z/VM operating system), and through its operating systems (notably z/OS with its key-protected address spaces and sophisticated goal-oriented workload scheduling, but also Linux and Java). This virtualization is so thorough, so well established, and so reliable that most IBM mainframe customers run no more than two machines: one in their primary data center, and one in their backup data center (fully active, partially active, or on standby, in case there is a catastrophe affecting the first building). All test, development, training, and production workload for all applications and all databases can run on a single machine, except for extremely large demands where the capacity of one machine might be limiting. Such a two mainframe installation can support continuous business service, avoiding both planned and unplanned outages.
Mainframes are designed to handle very high volume input and output (I/O) and emphasize throughput computing. Since the mid-1960's, mainframe designs have included several subsidiary computers (called channels or peripheral processors) which manage the I/O devices, leaving the CPU free to deal only with high-speed memory. It is common in mainframe shops to deal with massive databases and files. Giga-record or tera-record files are not unusual. Compared to a typical PC, mainframes commonly have hundreds to thousands of times as much data storage online, and can access it much faster.
Mainframe return on investment (ROI), like any other computing platform, is dependent on its ability to scale, support mixed workloads, reduce labor costs, deliver uninterrupted service for critical business applications, and several other risk-adjusted cost factors. Some argue that the modern mainframe is not cost-effective. Hewlett-Packard and Dell unsurprisingly take that view at least at times, and so do a few independent analysts. Sun Microsystems used to take that view but, beginning in mid-2007, started promoting its new partnership with IBM, including probable support for the company's OpenSolaris operating system running on IBM mainframes. The general consensus (held by Gartner and other independent analysts) is that the modern mainframe often has unique value and superior cost-effectiveness, especially for large scale enterprise computing. In fact, Hewlett-Packard also continues to manufacture its own mainframe (arguably), the NonStop system originally created by Tandem. Logical partitioning is now found in many high-end UNIX-based servers, and many vendors are promoting virtualization technologies, in many ways validating the mainframe's design accomplishments.
Mainframes also have unique execution integrity characteristics for fault tolerant computing. System z9 servers execute each instruction twice, compare results, and shift workloads "in flight" to functioning processors, including spares, without any impact to applications or users. This feature, also found in HP's NonStop systems, is known as lock-stepping, because both processors take their "steps" (i.e. instructions) together. Not all applications absolutely need the assured integrity that these systems provide, but many do, such as financial transaction processing.
Despite these differences, the IBM mainframe, in particular, is still a general purpose business computer in terms of its support for a wide variety of popular operating systems, middleware, and applications.
Market
As of early 2006, IBM mainframes dominate the mainframe market at well over 90% market share, however IBM is not the only vendor. Unisys manufactures ClearPath mainframes, based on earlier Sperry and Burroughs product lines. Fujitsu's Nova systems are rebranded Unisys ES7000's. Hitachi co-developed the zSeries 800 with IBM to share expenses. Hewlett-Packard sells its unique NonStop systems, which it acquired with Tandem Computers, and Groupe Bull's DPS mainframes are available in Europe. Unisys and HP increasingly rely on commodity Intel CPUs rather than custom processors in order to reduce development expenses, while IBM has its own large research and development organization to introduce new, homegrown mainframe technologies.
History
Several manufacturers produced mainframe computers from the late 1950s through the 1970s. At this time they were known as "IBM and the Seven Dwarfs": Burroughs, Control Data, General Electric, Honeywell, NCR, RCA, and UNIVAC. IBM's dominance grew out of their 700/7000 series and, later, the development of the 360 series mainframes. The latter architecture has continued to evolve into their current zSeries/z9 mainframes which, along with the then Burroughs and now Unisys MCP-based mainframes, are among the few mainframe architectures still extant that can trace their roots to this early period. That said, while they can still run 24-bit System/360 code, the 64-bit zSeries and System z9 CMOS servers have nothing physically in common with the older systems. The larger of the latter IBM competitors were also often referred to as "The BUNCH" from their initials (Burroughs, UNIVAC, NCR, CDC, Honeywell). Notable manufacturers outside the USA were Siemens and Telefunken in Germany, ICL in the United Kingdom, and Fujitsu, Hitachi, Oki, and NEC in Japan. The Soviet Union and Warsaw Pact countries manufactured close copies of IBM mainframes during the Cold War; the Strela is an example of an independently designed Soviet computer.
Shrinking demand and tough competition caused a shakeout in the market in the early 1980s — RCA sold out to UNIVAC and GE also left; Honeywell was bought out by Bull; UNIVAC became a division of Sperry, which later merged with Burroughs to form Unisys Corporation in 1986. In 1991, AT&T briefly owned NCR. During the same period, companies found that servers based on microcomputer designs could be deployed at a fraction of the acquisition price and offer local users much greater control over their own systems given the IT policies and practices at that time. Terminals used for interacting with mainframe systems were gradually replaced by personal computers. Consequently, demand plummeted and new mainframe installations were restricted mainly to financial services and government. In the early 1990s, there was a consensus among industry analysts that the mainframe was a dying market as mainframe platforms were increasingly replaced by personal computer networks.
That trend started to turn around in the late 1990s as corporations found new uses for their existing mainframes and as the price of data networking collapsed in most parts of the world. The growth of e-business also dramatically increased the number of back-end transactions processed by mainframe software as well as the size and throughput of databases. Another factor currently increasing mainframe use is the development of the Linux operating system, which can run on many mainframe systems, typically in virtual machines. Linux allows users to take advantage of open source software combined with mainframe hardware RAS. Rapid expansion and development in emerging markets, particularly China, is also spurring major mainframe investments to solve exceptionally difficult computing problems, e.g. providing unified, extremely high volume online transaction processing databases for 1 billion consumers across multiple industries (banking, insurance, credit reporting, government services, etc.)
Mainframes vs. supercomputers
The distinction between supercomputers and mainframes is not a hard and fast one, but supercomputers generally focus on problems which are limited by calculation speed while mainframes focus on problems which are limited by input/output and reliability ("throughput computing") and on solving multiple business problems concurrently (mixed workload). The differences and similarities include:
Both types of systems offer parallel processing. Supercomputers typically expose it to the programmer in complex manners, while mainframes typically use it to run multiple tasks. One result of this difference is that adding processors to a mainframe often speeds up the entire workload transparently.
Supercomputers are optimized for complicated computations that take place largely in memory, while mainframes are optimized for comparatively simple computations involving huge amounts of external data. For example, weather forecasting is suited to supercomputers, and insurance business or payroll processing applications are more suited to mainframes.
Supercomputers are often purpose-built for one or a very few specific institutional tasks (e.g. simulation and modeling). Mainframes typically handle a wider variety of tasks (e.g. data processing, warehousing). Consequently, most supercomputers can be one-off designs, whereas mainframes typically form part of a manufacturer's standard model lineup.
Mainframes tend to have numerous ancillary service processors assisting their main central processors (for cryptographic support, I/O handling, monitoring, memory handling, etc.) so that the actual "processor count" is much higher than would otherwise be obvious. Supercomputer design tends not to include as many service processors since they don't appreciably add to raw number-crunching power.
There has been some blurring of the term "mainframe," with some PC and server vendors referring to their systems as "mainframes" or "mainframe-like." This is not widely accepted and the market generally recognizes that mainframes are genuinely and demonstrably different.
Statistics
An IBM zSeries 800 (foreground, left) running Linux.
Historically 85% of all mainframe programs were written in the COBOL programming language. The remainder included a mix of PL/I (about 5%), Assembly language (about 7%), and miscellaneous other languages. eWeek estimates that millions of lines of net new COBOL code are still added each year, and there are nearly 1 million COBOL programmers worldwide, with growing numbers in emerging markets. Even so, COBOL is decreasing as a percentage of the total mainframe lines of code in production because Java, C, and C++ are all growing faster. Even then COBOL remains to be the most widely used language for developement in mainframe environment as it is most suited for business logic programming which is why the mainframes are really deployed.
Mainframe COBOL has recently acquired numerous Web-oriented features, such as XML parsing, with PL/I following close behind in adopting modern language features.
90% of IBM's mainframes have CICS transaction processing software installed.[2] Other software staples include the IMS and DB2 databases, and WebSphere MQ and WebSphere Application Server middleware.
As of 2004, IBM claimed over 200 new (21st century) mainframe customers — customers that had never previously owned a mainframe. Many are running Linux, some exclusively. There are new z/OS customers as well, frequently in emerging markets and among companies looking to improve service quality and reliability.
In May, 2006, IBM claimed that over 1,700 mainframe customers are running Linux. Nomura Securities of Japan spoke at LinuxWorld in 2006 and is one of the largest publicly known, with over 200 IFLs in operation that replaced rooms full of distributed servers.
Most mainframes run continuously at over 70% busy. A 90% figure is typical, and modern mainframes tolerate sustained periods of 100% CPU utilization, queuing work according to business priorities without disrupting ongoing execution.
Mainframes have a historical reputation for being "expensive," but the modern reality is much different. As of late 2006, it is possible to buy and configure a complete IBM mainframe system (with software, storage, and support), under standard commercial use terms, for about $50,000 (U.S.), equivalent to approximately 50% of the full annual cost of only one IT employee. The price of z/OS starts at about $1,500 (U.S.) per year, including 24x7 telephone and Web support.[3]
Speed and performance
The CPU speed of mainframes has historically been measured in millions of instructions per second (MIPS). MIPS have been used as an easy comparative rating of the speed and capacity of mainframes. The smallest System z9 IBM mainframes today run at about 26 MIPS and the largest about 17,801 MIPS. IBM's Parallel Sysplex technology can join up to 32 of these systems, making them behave like a single, logical computing facility of as much as about 569,632 MIPS.[4]
The MIPS measurement has long been known to be misleading and has often been parodied as "Meaningless Indicator of Processor Speed." The complex CPU architectures of modern mainframes have reduced the relevance of MIPS ratings to the actual number of instructions executed. Likewise, the modern "balanced performance" system designs focus both on CPU power and on I/O capacity, and virtualization capabilities make comparative measurements even more difficult. See benchmark (computing) for a brief discussion of the difficulties in benchmarking such systems. IBM has long published a set of LSPR (Large System Performance Reference) ratio tables for mainframes that take into account different types of workloads and are a more representative measurement. However, these comparisons are not available for non-IBM systems. It takes a fair amount of work (and maybe guesswork) for users to determine what type of workload they have and then apply only the LSPR values most relevant to them.
To give some idea of real world experience, it is typical for a single mainframe CPU to execute the equivalent of 50, 100, or even more distributed processors' worth of business activity, depending on the workloads. Merely counting processors to compare server platforms is extremely perilous.
Courtesy: Wikipedia.com

FINAL SUGGESTION FOR CSE 101

noreply@blogger.com (TANVIR) — Mon, 8 Aug 2011 09:07:00 +0600

Objective: From Lecture 1-5 and the whole book 1.a-13.b
Chapter 1
1. List the four parts of a computer system.
2. Identify four types of computer hardware
3. Differentiate the two main categories of computer software
4. Identify two unique features of supercomputers.
5. Describe a typical use for mainframe computers
6. Differentiate workstations from personal computers
7. Name four components found in most graphical user interfaces.
8. Describe the operating system’s role in running software programs.
9. Name five types of utility software.
10. What is OS? List the four primary functions of an OS.
11. What is GUI? What is software? Classify with example.
Chapter 2
1. List the two most commonly used types of computer monitors.
2. Explain how a CRT monitor displays images.
3. List four characteristics you should consider when comparing monitors.
4. List the four criteria you should consider when evaluating printers.
5. Describe how a dot matrix printer creates an image on a page.
6. Explain the process by which a laser printer operates.
7. Explain how data is stored on the surface of magnetic and optical disks.
8. Explain the difference between RAM and ROM.
9. List three hardware factors that affect processing speed

Chapter 3
1. Jacob likes to read. Last month he made a goal to read at least (466)8 pages from his book collection each week. How many pages did he read after (10110)2 weeks? He told his mother it would be equivalent to reading the (8E1)16 page Harry Potter and the Deathly Hallows (011)2 times. Was he correct? Explain your answer.
2. Cimorene spent an afternoon cleaning and organizing the dragon’s treasure. One fourth of the items she sorted were jewelry. (3C %)16 of the remainder were potions, and the rest were magic swords. If there were (110000)2 magic swords, how many pieces of treasure did she sort in all?
3. In Brac University randomly pick 3 clubs where they ask them to submit their annual profit for year 2007-2008. Drama Club, Computer Club and Business club submitted their annual profit as follows.
a. Drama Club – (E7BA.A)16
b. Computer Club - (163672.636)8
c. Business Club - (1110000110010.1101)2

Then Brac University decided to give all of them TK. 1485.6125. So they intend to write a check according to the format that the club uses to submit there annual balance. Write what amount they write on there checks according to the club format and what is the total of all 3 club annual profit in decimal. To get full credit show your steps.
4. From 2003 Till 2007 Bhuiyan Group of Industries donates WHO (World Health Organization). At the end of year 2008 hey waned o know how much Total money they donate so far. And based on the total amount they wanted to donate 50% of the total donation to year 2008. How much money in decimal hey will donate at year 2008?

Year Amount
2003 (ABC7.D)16
2004 (1010110110010.1101)2
2005 (73672.636)8
2006 (67252.500)8
2007 (D7E7.D)16
5. Addition and conversation.
• (6F.3C)16 + (203.25)8 = (????)16
• (A1D)16 + (346.74)8 = (????)8
• (4C.B7)16 + (123.46)8 = (????)10
• (9D.AB6)16 + (306.51)8 = (????)2
• (AD.BD)16+ (603.46)8+ (952.99)10+ (11011011.1101)2 = (????)10

6. Faraz, Kabir and faruqe made a club called “The Junto” to read books and discuss ideas. Ben read (232)8 science books. He read (E)16 times as many history books as science books. How many more history books than science books did he read? What is the total amount of book did he read? How many more book he need to read to complete total (11100000011)2?
7. Faraz collected donations for many worthy organizations. He had (2467.AD)16 Taka in a bank account to start a new hospital. OMAR gave him another (11010011.011000)2 Taka. How much more money must Faraz collect from kabir if he needs (EAEE)16 Taka for the hospital in decimal?
8. The day before the great battle at the Black Gate, a company of (1C2)16 orcs camped among the host of Mordor. But an argument broke out over dinner, and 1/3 of them were killed. Then 2/5 of the remainder died when a drunken troll stumbled through their camp during the night. (1101)2 of them run away from the battle field. How many of the orcs left to join the morning’s battle?
9. Draw flowchart for printing Sequence: 1, 3, 5, 9… N
10. Draw flowchart for printing Sequence: 2, 4, 6, 8… N
11. draw flowchart for printing Sequence: 1,-1, 2,-2, 3,-3……….n.-n
12. Write a flowchart where it prints all the number till N which divisible by 5 or 10 or 3
13. draw flowchart for printing Sequence: ½, 2/4, 3/6, 4/8 …n/2n
14. draw a flowchart for GPA calculation for N number of class.
15. draw a flowchart for printing he sequence of 1,-3, 5,-7 ...n
16. draw a flowchart for Fibonacci series.(ex: 0,1,1,2,3,5,8,13.....Nnth where Nnth = N(nth-1)+N(nth-2)
17. Draw a flowchart for N factorial series. (Ex: 5! =5*4*3*2*1)
18. draw flowchart for printing Sequence: 1+2+3+4+...+N or Write pseudo code and draw flowchart for printing Sequence: 2+4+6+8+…. +N OR 1+3+5+9+...+N

Chapter 4
1. What is Computer Network? What is WAN? What is LAN? What is MAN?
2. What is topology? How many types of topologies are there? Explain them with diagram.
3. What Topologies are appropriate for LAN?
4. What is the different between WAN and MAN?
5. What is the difference between data and information?
6. If you have to talk to a robot, name the devices and techniques that need to be in the robot to achieve the interaction requirement.
7. What are Intranet, Extra net and Internet? Explained there uses.
8. What is Database? Differentiate between database and Database Management Systems.
9. Describe different Levels of Abstraction.
10. What are DDL and DML?
11. What is the difference between procedural and non-procedural language?
12. Define Instances and Schemas. What is the role of database administrator?
13. What is File System Data Management?
14. What is data Dependency? What is Data Redundancy?
15. What is the difference between Relational Database and Non-Relational Database?
16. Why database management system is important from file management system?
Chapter 5
1. What is Software? What is software Engineering, computer Science and System Engineering?
2. What is the difference between software Engineering and computer Science and system engineering?
3. What are the generic activities of all software processing?
4. What are the attribute of good software? Explain any 5.
5. Write down the steps of waterfall model. What are the disadvantages of waterfall model?
6. What is process Model? What are the weaknesses of process Model?
7. What is the professional and ethical responsibility as a Software Engineer? Give 2 responsibilities that every software engineer should follow.
8. What is the code of ethics that engineers should follow?
9. What is Computer Virus? Give at least 5 category of virus type?
10. How does virus affect us? How we can prevent our computer from viruses?
11. What is Data Theft? How we can prevent our data from Hackers?
12. What is Integrity? What is cryptography?

Encrypt or Decrypt this using confusion Method
• Key 11
O Plaintext:
 No one has yet realized the wealth of sympathy, the kindness and generosity hidden in the soul of a child. The effort of every true education should be to unlock that treasure.
O Cipher Text:
 YZ ZYP SLD JPE CPLWTKPO ESP HPLWES ZQ DJXALESJ, ESP VTYOYPDD LYO RPYPCZDTEJ STOOPY TY ESP DZFW ZQ L NSTWO. ESP PQQZCE ZQ PGPCJ ECFP POFNLETZY DSZFWO MP EZ FYWZNV ESLE ECPLDFCP.

• Key 13
o Plaintext:
 Education is not the filling of a pail, but the lighting of a fire.

O Cipher Text:
 RQHPNGVBA VF ABG GUR SVYYVAT BS N CNVY, OHG GUR YVTUGVAT BS N SVER.

• Key 17
O Plaintext:
 It is the mark of an educated mind to be able to entertain a thought without accepting it.
O Cipher Text:
 ZK ZJ KYV DRIB FW RE VULTRKVU DZEU KF SV RSCV KF VEKVIKRZE R KYFLXYK NZKYFLK RTTVGKZEX ZK.

• Key 23
o Plaintext:
 Education is simply the soul of a society as it passes from one generation to another.
o Cipher Text:
 BARZXQFLK FP PFJMIV QEB PLRI LC X PLZFBQV XP FQ MXPPBP COLJ LKB DBKBOXQFLK QL XKLQEBO.

• Key 05
o Plaintext:
 The roots of education are bitter, but the fruit is sweet.
o Cipher Text:
 YMJ WTTYX TK JIZHFYNTS FWJ GNYYJW, GZY YMJ KWZNY NX XBJJY.

• Key 05
o Plaintext:
 Part of the inhumanity of the computer is that, once it is competently programmed and working smoothly, it is completely honest.
o Cipher Text:
 UFWY TK YMJ NSMZRFSNYD TK YMJ HTRUZYJW NX YMFY, TSHJ NY NX HTRUJYJSYQD UWTLWFRRJI FSI BTWPNSL XRTTYMQD, NY NX HTRUQJYJQD MTSJXY.

• Key 06
o Plaintext:
 The Internet is not just one thing, it's a collection of things - of numerous communications networks that all speak the same digital language.

o Cipher Text:
 ZNK OTZKXTKZ OY TUZ PAYZ UTK ZNOTM, OZ'Y G IURRKIZOUT UL ZNOTMY - UL TASKXUAY IUSSATOIGZOUTY TKZCUXQY ZNGZ GRR YVKGQ ZNK YGSK JOMOZGR RGTMAGMK..

• Key 09
o Plaintext:
 Treat your password like your toothbrush. Don't let anybody else use it, and get a new one every six months.
o Cipher Text:
 CANJC HXDA YJBBFXAM URTN HXDA CXXCQKADBQ. MXW'C UNC JWHKXMH NUBN DBN RC, JWM PNC J WNF XWN NENAH BRG VXWCQB.

140. Encrypt or Decrypt this using Diffusions Method.
Key 05
i. Plaintext:
i. The roots of education are bitter, but the fruit is sweet.
j. Cipher Text L1
i. TOETRTTRST
ii. HTDIEETUS
iii. ESUOBRHIW
iv. ROCNIBETE
v. OFAATUFIE
k. Cipher Text L2
i. ESUOBRHIW
ii. HTDIEETUS
iii. OFAATUFIE
iv. ROCNIBETE
v. TOETRTTRST

P-Box
Level 1 1 2 3 4 5
Level2 5 2 1 4 3

THE COMPUTING FIELD IS ALWAYS IN NEED OF NEW CLICHES.

TTDSFH HIIINE ENSNES CGANW OFLEC MIWEL PEADT ULYOC

CGANW ENSNES HIIINE MIWEL OFLEC PEADT TTDSFH ULYOC

Cipher Text: CGANW ENSNES HIIINE MIWEL OFLEC PEADT TTDSFH ULYOC

P-Box
Level 2 1 2 3 4 5 6 7 8
Level 1 7 3 2 1 5 4 6 8

COMPUTER SCIENCE ( CSE101) TERM PAPER TOPIC

noreply@blogger.com (TANVIR) — Sun, 31 Jul 2011 10:48:00 +0600

Topic of The Term Paper

1. Cloud Computing IN BUSINESS

2. Call Center in Bangladesh and its Technical Aspacts

3. Sales Managment System of a Pharmacy / Hospital

4. Hotel Management System and its Technical Aspacts

5. Tele- Communication System

6. Any New Technology Comeing to the market and its technical aspects(eg. Microsoft Surface)

7. communication system and its IT and Bussiness Infrastructure

FURTHERMORE, IF THERE IS ANY FORM OF CHEATING DETECTED, SPECIALLY ACROSS SECTIONS, BOTH PARTIES WILL GET ZERO, IRRESPECTIVE OF SOURCE OR DESTINATION

GROUP PROJECT:

This would be Computer management and information technology paper. This paper must be 20-25 page text; diagrams do not count towards the total. Using MS Visio for diagram/pictures explaining current process (AS-IS) and Future process (TO_BE) is mandatory. Here are the major issues for the paper. Not all these issues would apply to each project. Try to cover at least 10/12 important issues in your paper to receive good grade. (It will be explained more in class)

Backup/Recovery

Security/Password

Training/ cross training

Capacity for growth

Sizing hardware/software for full production implementation

Documentation

Support/helpdesk/tutorial

Applications, Supplier /client Compliance

End user involvement

Executive sponsorship

Long-term maintenance of application & hardware

Ethical considerations (Privacy etc.)

Efficiency/effectiveness

Cost Benefit Analysis

Business requirement

Database: integrity/duplication/ dependency/redundancy /consistency

System Development Life Cycle

Testing Methodology

Project Management

Formal application development methodology

Formal project planning strategy

Change Management

MANAGEMENT 211 CHAPTER 17 SEGMENT 3

noreply@blogger.com (TANVIR) — Tue, 19 Jul 2011 10:48:00 +0600

CHAPTER 17

LEADERSHIP

Leader: someone who can influence others and who has managerial power. ( ja onno der influence korta para and jar managerial power asa0

Leadership: the process of influencing a group toward the achievement of goal. ( ja prokiay akta group k influence kora hoy jata goal achieve kora jai. ja kau leadership power pata para but ja kau leader hota para na. leader hota hola upor ar authorityr power laga)

Traits theory:

The main theme of this theory is to dedifferentiate leaders from nonreaders by their traits. To dedifferentiate leaders from nonreaders there should be 7 traits in a leader or “leaders are by born leader” to full fill this quote there should be 7 characteristic or traits in a leader. (Mana traits theory bola ja 7 traits or boishisto akta leader ar maja thakta hoba ja akta leader k onnoanoder chaya alada korba or quote ta puron korba)

Drive: a leader is ambitious and has high desire for achievement. He should exhibit or show high level of effort to achieve organizational goals. ( mana akta leader k ambitious and achievement ar akankha thakta hoba. Ar organizational gola achieve ar jonnno high effort show korta hoba.
Desire to lead: leaders must have a strong desire to lead or influence others.
Honesty and integrity: a leader must be honest and build a trusting relation between subordinates.
Self confidence: a leader must be self-confidence to convince his followers and help them to take decision and solve problems.
Intelligence: leaders need to be intelligent enough to solve problems and create decisions.
Jobs relevant knowledge: a leader must have knowledge about the company, industry and technical matters.
Extraversion: a leader should come up and break down introvert ness from their subordinates.

Behavioral theories:

Behavioral theories refers that how leadership change the behavior by four main behavior studies.

Iowa university studies: This University explored three leadership styles.

o Autocratic style: dictating work method, centralization decision makings, limited participation. ( sob decision upper level niba)

o Democratic style: involving subordinate, delegating work and encouraging participation. ( mana sobay participation korta parba)

o Laissez-faire: giving group freedom to make decision and complete work. (Mana manager freedom dia day subordinate der kaj korar ar employee rat a deadline ar aga shash kora Dai.)

Ohio state studies: it identified two important dimension of leader behavior.

o Consideration : being considerate of followers ideas and feelings in job relationship by establishing mutual trust and respect for group members

o Initiating structure: structuring work and work relationship to meet job goals. ( job relationship k akta structure daaya jata ta job ar goal meet korta para)

University of Michigan studies: This study also comes up with two dimension of leadership behavior.

o Employee oriented: emphasized interpersonal relationship and taking care of employees need.

o Production oriented: emphasized on the technical aspect of the job. Here accomplishing group task is the main concern.

Managerial grid: used the behavioral dimensions “concern fro people” and “concern for production”

Concern for people : evaluating leaders behaviors , ranking them on a scale from 1 to 9
Concern for production: emphasized technical or task aspect of jobs.

Although the grid had 81 potential categories into which a leader’s behavior can fall into which leaders behavioral style might fall, emphasizes on five.

Impoverished management (1, 1): exertion of minimum effort to get required work done is appropriate to sustain organization membership. ( mana minimum effort dia required work kora ata organization a tika thakar jonno projozzo)
task management (9,1) : efficiency in operation results from arranging result condition of work in such a way that human elements interfere to minimum degree( mana amr work setting daya thakba ami employee hire korbo then production korbo)
Middle of the road (5, 5): adequate organization performance is possible through balancing the necessity to get out work with maintaining morale or confidence of people at a satisfactory level.
country club management (1,9): thoughtful attention to needs of people for satisfying relationship leads to a comfortable, friendly organization, atmosphere and work tempo ( mana valo akta relation create kora organization ar bhitor and production nia tara tamon chinta kora na . such as NGO)
Team management (9, 9): work accomplished from committed people; interdependence through a “common stake” in organization purpose leads to relationships of trust and respect. ( mana built up good relationship and much production)

Contingency theories of leadership:

The Fiedler model: proposed that effective group performance depend on the proper match between the leader’s style with his or her followers and the degree to which the situation allowed the leader to control and influence. To measure leaders style Fiedler developed LPC questionnaire.

LPC: measured whether a leader was task or relationship oriented.

Fiedler research uncovered three contingency dimension that defined the key situational factors for determining leader effectiveness

Leader member relations: refers that trust and respect employee had for their leader
Task structure: refers that job assignments were formalized and procedurized; rated as either high or low
Position power: refers influence leader had over power based activities such as hiring, firing, discipline and salary increase.

Heresy and Blanchard’s situational leadership theory

Situational leadership theory (SLT): focuses on the follower’s readiness.

Readiness: refers people have the ability and willingness to accomplish a specific task.

SLT uses the same two leadership dimensions that fielder identified: task and relationship behaviors. But heresy goes a step further by considering them into four specific leadership styles. (See pages 429)

Leader participating model: refers to contingency model that related leadership behavior and participation in decision making.

Leadership styles in the vroom leader participation

Decide
Consult individually
Consult group
Facilitate
Delegates

Path-goal

A leadership theory that says it’s the leader’s job to assist his or her follower in attaining their goals and to provide the direction or support needed to ensure that their goals are compatible with the overall objectives of the group or organization.

Directive leadership: lets subordinate know whats expected from them , schedule work to be done, and gives specific guidance on how to accomplish task
Supportive leadership: is friendly and shows concern for the needs of followers.
Participating leader: consults with the groups members and uses their suggestion before making decision.
Achievement oriented leader: sets challenging goals and expects followers to perform at their highest level.

If path goal theory goal comes in the exam then you have to answer the following

Environment contingency factors

Task structure
Formal authority system
Work group

↓

Leader behavior Outcomes

· Directive performance, satisfaction

· Supportive →

· Participative

· Achievement oriented

↑

Subordinate contingency factors

Locus of control
Experience
Perceived ability

MANAGEMENT 211 CHAPTER 10 SSEGMENT 2

noreply@blogger.com (TANVIR) — Fri, 15 Jul 2011 19:23:00 +0600

CHAPTER 10

ORGANIZATION STRUCTURE AND DESIGN

Organizational structure:

The formal arrangement of job with in an organization

Organizational design:

Developing or changing the structure of organization

Purpose of organizing

Divide the work into specific jobs and departments. ( work k bhabg kora daya uchit job ar maddhoma and department gulu ta)
Assigning task and responsibilities associated with individual jobs.
Cluster jobs into unit ( job gula k akta unit ar aota bhukto korta hoba)
Establishing relationship among group, individual etc
Coordinate diverse organization task.
Allocate organizations resources
Establishing formal authority line

WORK SPECIALIZATION:

The task of an organization divvied into jobs; also known as division of labor ( kaj bhag kora daya). Some times because of jobs specialization boring, fatigue, stress, poor quality, and higher turnover took place. Coz onak somoy ak kaj korta korta manush physic hoya jay.

Departmentalization;

The basis jobs are grouped toghter. There are 5 types of departmentalization.

Functional departmentalization: groups jobs by functioned perform. Advantages: coordination with in functional areas, in depth specialization, people within common skill and knowledge. Disadvantages: poor communication across functional areas, limited view of organization.
Geographical departmentalization: groups jobs on the basis of territory or geography. Advantages: more effective and efficient handling of specific regional ( mana USA , sell director usa ta valo sale korta parba but BD ta na abar BD ar sale director ar khatrao same ) , serves the unique geography market better. Disadvantages: duplication of function, can feel isolated from other organizational area.
Product departmentalization: groups jobs by product line. Advantage: manager can become expert in the industry, closer to customer. Disadvantage: duplication of function, limited view of organization.
Process departmentalization: groups jobs by on the basis of product or customer flow. Advantages: more efficient flow in work activities. Disadvantages: can only be used in certain types of product.
Customer departmentalization: groups jobs by on the basis of common customer. Advantages: customer need and problems can be meeting by specialist. Disadvantage: duplication of work, limited view of organization.

Chain of command: the continuous line of authority that starts from upper level to lower level and clarify that who will report to whom.

Authority: the rights inherent in the managerial position to tell people what to do and to expect them to do it.

Responsibility: the expectation to perform any assigned task.

Unity of command: refers that each person should only report to one manager.

Span of control: the number of employee a manager can control efficiently and effectively ( jamon akta organization a akta manger aksatha 4 jon kormi control korta para abr onno organization a akta manager aksatha 10 ta kormi manage korta para) . it also represent the skill of a manager.

Centralization: all the decision of an organization taken by the top management of an organization.

Decentralization: lower employee can take part in decision making.

Formalization:

Refers that jobs are standardized and extend the behavior of employees controlled by rules and regulation of the organization. ( mana job k akta standard rup daya hoi ar organization employee dr rules and regulation a rakha hoy ) .

Mechanistic organization: organization structure is rigid and tightly controlled.

Organic organization: Organization structures are highly adaptive and flexible.

Strategy and structure:

Innovation: reflects the organization pursuit of meaningful and unique innovation.
Cost minimizing: reflects organization tightly control the cost.
imitation : reflect organization minimize the cost and maximize the profit by coping the market leader ( jamon reds eye akdm dell k copy kora pc banay at ta sale kora ata kora red eye ar research cost kom hoy but profit basi hoy )

Technology and structure:

Every organization should have at least one technology to convert its input into output.

Unit production: production of items in unit or batches.
Mass production: production of items in large batches.
Process production: continuous process production.

Organizational structures are divides into 2 parts.

traditional structure
contemporary structure

Traditional organization design:

Simple structure: an organizational design with low departmentalization, wide span of control, centralized authority and little formalization. Advantages: fast, flexible, inexpensive to maintain. Disadvantages: not appropriate when organization grow.

Functional structure: an organizational design that groups similar or related occupational specialist toghter. Advantages: cost saving advantages from specialization. Disadvantages: functional unit have little knowledge what other is doing.

Divisional structure: an organizational design that made up of separate, semi autonomous unit or division. Advantages: focus on their result. Disadvantages: duplication of activities.

Contemporary organizational structure (present organization structure)

Team structure: a structure in which entire organization is made up of work group. Advantages: employees are more involved and empowered. Disadvantages: no clear chain of command.
Matrix project structure: an organizational structure assign specialist from different division to work on one or more project. Advantages: faster decision making. Disadvantages : tasks and personality conflict
Boundary less structure: a structure that is not defines by or limited to horizontal, vertical or external boundaries. It includes network modular and virtual organization. Advantages: highly flexible and responsive. Disadvantages: lack of control.

Virtual organization: an organization that has small number of full employee and they temporarily hires outside employees to work. Such as consultant
Network organization: a small core organization that outsource major business. Such as Freelancing.
Modular organization: a manufacturing organization that use outside suppliers to provide products. Component and module that are then assembled into final products. Such as radhuni food products.

4. Learning organization: structure that supports and organizations capacity to continuously adapt and change.

HUMANITIES 101 SEGMENT 2

noreply@blogger.com (TANVIR) — Mon, 11 Jul 2011 17:45:00 +0600

JAMES WATT
James Watt was a Scottish inventor and mechanical engineer whose improvements to the Newcomer were fundamental to the changes brought by the Industrial Revolution in both the Kingdom of Great Britain and the world.
While working as an instrument maker at the University of Glasgow, Watt became interested in the technology of steam engines. He realized that contemporary engine designs wasted a great deal of energy by repeatedly cooling and re-heating the cylinder. Watt introduced a design enhancement, the separate condenser, which avoided this waste of energy and radically improved the power, efficiency, and cost-effectiveness of steam engines. He developed the concept of horsepower. The SI unit of power, the watt, was named after him.
Watt attempted to commercialize his invention, but experienced great financial difficulties until in 1775 he entered a partnership with Matthew Boulton. The new firm of Boulton and Watt was eventually highly successful and Watt became a wealthy man. In retirement, Watt continued to develop new inventions though none were as significant as his steam engine work. He died in 1819 at the age of 83. Watt has been described as one of the most influential figures in human history.

MARTIN LUTHER
Martin Luther was a German priest and professor of theology who initiated the Protestant Reformation. He strongly disputed the claim that freedom from God's punishment of sin could be purchased with money.
Luther taught that salvation is not earned by good deeds but received only as a free gift of God's grace through faith in Jesus Christ as redeemer from sin. theology challenged the authority of the pope of the Roman Catholic Church by teaching that the Bible is the only source of divinely revealed knowledge and opposed sacerdotalism by considering all baptized Christians to be a holy priesthood. Those who identify with Luther's teachings are called Lutherans.
His translation of the Bible into the language of the people made it more accessible, causing a tremendous impact on the church and on German culture. It fostered the development of a standard version of the German language, added several principles to the art of translation and influenced the translation into English of the King James Bible. His hymns influenced the development of singing in churches. His marriage to Katharina von Bora set a model for the practice of clerical marriage, allowing Protestant priests to marry.
In his later years, while suffering from several illnesses and worsening health, Luther became increasingly anti-Semitic, writing that Jewish homes should be destroyed, their synagogues burned, money take away and liberty reduced. These statements have contributed to his controversial status.

REIGN OF TERROR
Reign of Terror lasted from September 1793 until the fall of Robespierre in 1794. Its purpose was to clean France of enemies of the Revolution and protect the country from foreign invaders. From January 1793-July 1794, France was governed by the Committee of Public Safety, in which Danton and Robespierre were influential members. In the course of nine months, 16, 000 people were put to death, but executions of those labeled "internal enemies" of France took place throughout the country.
During this time there was a shift in power within the committee from Danton to Robespierre. Danton had a strong physical presence and was an incredible public speaker, while Robespierre was less passionate. However, Robespierre was a hard worker who was very ambitious. He blindly believed in the work of Rousseau, who argued that men are all born good at heart and are corrupted by society. It was these beliefs that caused him to continue the Terror even when it was no longer necessary.
In 1794, the armies of France were very successful against their enemies, which meant that the Terror was no longer necessary. But Robespierre continued the Terror because he wanted to purge France of everyone who was corrupt. The killing ended when Robespierre was executed on July 28, 1794.

Medieval university
Medieval sity is an institution of higher learning which was established during High Middle Ages period and is a corporation. The first institutions generally considered to be universities were established in Italy, France, and England in the late 11th and the 12th centuries for the study of arts, law, medicine, and theology. These universities evolved from much older Christian cathedral schools and monastic schools, and it is difficult to define the date at which they became true universities.
Prior to their formal establishment, many medieval universities were run for hundreds of years as Christian cathedral or monastic schools in which monks and nuns taught classes. With the increasing growth and urbanization of European society during the 12th and 13th centuries, a demand grew for professional clergy.
Initially medieval universities did not have a campus. Classes were taught wherever space was available, such as churches and homes. Soon, however, some universities began to buy or rent rooms specifically for the purposes of teaching. Universities were generally structured along three types, depending on who paid the teachers. The first type was in Bologna, where students hired and paid for the teachers. The second type was in Paris, where teachers were paid by the church. Oxford and Cambridge were predominantly supported by the crown and the state. At the Bologna University the students ran everything—a fact that often put teachers under great pressure and disadvantage. In Paris, teachers ran the school; thus Paris became the premiere spot for teachers from all over Europe. University studies took six years for a Bachelor's degree and up to twelve additional years for a master's degree and doctorate. Courses were offered according to books, not by subject or theme. Students entered the University at fourteen to fifteen years of age. Classes usually started at 5:00 or 6:00 AM.
Treaty of Versailles
There were many peace treaties signed at the end of the World War I. One of them was the treaty of Versailles. It was with this treaty that the war between Germany and the Allied Power ended. For the other powers involved in the war on the side of Germany, different treaties were signed. The war actually ended on 11th November 1918 after the signing of the armistice. The negotiations took as long as 6 months. It was Paris Peace Conference, which did the negotiations. This brings us to the question, who signed the treaty of Versailles. It was the Foreign Minister of Germany Herr. Hermann Muller. The Colonial Minister Herr. Johannes Bell who traveled with the Foreign Minister to Versailles to sign the treaty. The other treaty of Versailles signatories were the British Empire, France, Italy, Japan and the United States of America.
The main terms of the Versailles Treaty were:

(1) the surrender of all German colonies as League of Nations mandates;

(2) the return of Alsace-Lorraine to France;

(3) cession of Eupen-Malmedy to Belgium, Memel to Lithuania, the Hultschin district to Czechoslovakia,

(4) Poznania, parts of East Prussia and Upper Silesia to Poland;

(5) Danzig to become a free city;

(6) plebiscites to be held in northern Schleswig to settle the Danish-German frontier;

(7) occupation and special status for the Saar under French control; (8) demilitarization and a fifteen-year occupation of the Rhineland;

(9) German reparations of £6,600 million;

(10) a ban on the union of Germany and Austria;

(11) an acceptance of Germany's guilt in causing the war;

(11) provision for the trial of the former Kaiser and other war leaders;

(12) limitation of Germany's army to 100,000 men with no conscription, no tanks, no heavy artillery, no poison-gas supplies, no aircraft and no airships;

(13) the limitation of the German Navy to vessels under 100,000 tons, with no submarines;

NOTES FOR TOPIC 8

NOTES FOR TOPIC 9

NOTES FOR TOPIC 10

HUMANITIES 101 SEGMENT 1

noreply@blogger.com (TANVIR) — Mon, 11 Jul 2011 16:57:00 +0600

HUMANITIES 101 FOR BETTER QUALITY PICTURE MAIL MAIL ME @ tanvirfalcon@gmail.com

COURSE OUTLINE

SUGGESTION FOR HUM 101

LECTURE 1

IMPORTANT FOR THIS CHAPTER

CULTURE AND CIVILIZATION
PROCESS OF THE HUMAN EVOLUTION ( HOMINIDS TO HOMO-SAPIENS)
CHARACTERISTIC OF PALEOLITHIC AGE

CHAPTER 2

IMPORTANT FOR THIS CHAPTER ( REGISTER OR FOLLOWER WILL GET THE NOTE)

CHARACTERISTIC OF NEOLITHIC AGE
DIFFERENCE BETWEEN PALEOLITHIC AND NEOLITHIC AGE
NEOLITHIC FAMILY

CHAPTER 3

IMPORTANT FOR THIS CHAPTER ( REGISTER OR FOLLOWER WILL GET THE NOTE VIA EMAIL)

SUMERIAN SCRIPT
ZIGGURAT
DIFFERENCE BETWEEN SUMERIAN AND BABYLONIAN LAW
CODE OF HAMURABI

CHAPTER 4

IMPORTANT FOR THIS CHAPTER

PYRAMIDS
MUMIFICATION

CHAPTER 5

IMPORTANT FOR THIS CHAPTER ( REGISTER OR FOLLOWER WILL GET THE NOTE)

INDUS VALLEY CIVILIZATION
ARYAN RELIGION
ARYAN CASTE SYSTE

CHAPTER 6
IMPORTANT FOR THIS CHAPTER ( REGISTER OR FOLLOWER WILL GET THE NOTE)

CONFUCIANISM
TAOISM
GREAT WALL

CHAPTER 7

IMPORTANT FOR THIS CHAPTER ( REGISTER OR FOLLOWER WILL GET THE NOTE)

PERSIAN CIVILZATION
ZOROASTRIANISM

CHAPTER 8

IMPORTANT FOR THIS CHAPTER

CITY STATES
SOCRATES
ARISTITILE

CHAPTER 9
IMPORTANT FOR THIS CHAPTER

ROMAN SOCITEY
ECONOMY
LAW

CHAPTER 10
IMPORTANT FOR THIS CHAPTER

MANOR
CHIVALRY
CHRISTIANITY
MEDIEVAL UNIVERSITY

GEO 101 LECTURE SEGMENT 4

noreply@blogger.com (TANVIR) — Sun, 10 Jul 2011 15:19:00 +0600

LECTURE 12

Trade

Maximum content of this chapter is important for quiz and final

( VERY IMPORTANT)Trade is an economic activity in the tertiary sectors, by which Homo sapiens are involved in the exchange of goods and services between two or between more than two parties involving monetary or non-monetary transactions.

Trading can occur in two ways-

v Informal trade

v Formal trade

Informal trade ( VERY IMPORTANT)

Informal trade is also known as Barter trade. People at first started trade with this. In this trade two parties are involved in non-monetary transaction.

Formal trade ( VERY IMPORTANT)

Formal trade means exchanging of goods and services between two or more than two parties involving monetary transactions. Formal trade occur in two ways

q Internal trade

q International trade

Internal trade

Internal trade means involved in monetary transactions in the local currency and the trade is conducted within geographical boundaries of a given country.

International trade

International trade indicates exchange of goods and services involving monetary transactions in the hard currency and the trade entails crossing the international border.

There are two components of international trade

q Export

q Import

Export

Sending of demanded commodities to parties that are located in foreign countries.

Import

Receiving of a given demanded commodities from the parties that are located in foreign countries.

Balance of trade

Balance of trade is the subtraction of import trade from export trade. It could be either positive or negative. A country earn when the balance of trade is positive and the net return is also positive. The country losses when the balance of trade is negative.

LECTURE 13

Transportation

Transportation is an economic activity where we transport goods as well as passengers from one place to another in a certain distance.

Modes of transportation

1.Surface transportation

ü Surface transportation

§ Land

· Road

· Railway

§ Water

· River (inland water transportation)

· Marine

ü Air transportation

Road transport ( VERY IMPORTANT)

v Operates on small margins-operating cost high

v Wide area coverage

v Flexible and convenient

v Inadequate capacity for moving heavy volumes

v High costs of long hauls

Railway transport ( VERY IMPORTANT)

v Capital intensive- large initial investment

v Profit depend on intensity and use

v High terminal cost

v Increasing effectiveness with length of haul

v Large shipments cheaper by long or short haul

v Minerals, unprocessed products, building materials, chemicals are transported

v Large volumes of bulk goods

Water transport ( VERY IMPORTANT)

v Low investment, especially where natural waterways utilized

v Increasing effectiveness with length of haul

v Marine: semi finished and finished products are transported

v Inland: bulk raw goods- coal, oil, gravel, cement, brick etc. are transported.

Air transportation ( VERY IMPORTANT)

v Most expensive mode of transportation

v Mainly transport people from one place to another.

Transportation service ( VERY IMPORTANT)

q Inter regional transportation

q Intra regional transportation

Transportation service ( VERY IMPORTANT)

Ø Inter regional transportation

Ø Intra regional transportation

This is the transportation service within different cities. The nodes (urban centers) are connected by different modes of transportation.

Intra regional transportation is a transportation network, which is happening within the region. It is very urban specific for developed countries. People are important in intra-regional transportation because people have to communicate between home and workplace.

LECTURE 14
A NOTE WILL BE GIVEN ON THIS TOPIC SO BE WITH THIS BLOG

Connectivity of Transport Network

Any network has three elements

Ø The nodes

Ø The routes or edges

Ø Independent or unconnected part of the network

A useful first step in the analysis of network is to construct a connectivity matrix. This shows which nodes have direct links with each other and which do not have direct links. If each node are connected directly to every other node then all cell in table would contain the symbol 1. Thus the more frequently the symbol 1 appears in the matrix, the network is more interconnected.

The final measure of network characteristics to be discussed here is the b index. This provides an alternative way of describing the complexity of the network.

b index =e/v

e = number of edges/routs

v = number of nodes or vertex/vertices

An index 1 describes a network with just one circuit and the figure increases, as the structure of the network grows more complex, with an increasing number of edges in relation to vertices or nodes.

The location of transportation route & network

Transportation route do not exist in isolation. They are organized into networks with varying degrees of interaction. Interaction occurs between places if they have some kind of demand-supply relationship. If two urban centers are complementary but not connected by a transportation route will be constructed to meet need.

The cost of transportation consists of two basic elements.

Ø Fixed/ capital costs: these are the cost involved in actually building the route.

§ Uneven ground may have to be leveled.

§ Water logged ground drained and filled.

Ø Variable /operating costs: are recurrent costs, which vary according to both the length of route and the volume of traffic flowing along it. Routes have to be maintained and kept in good repairs.

These two cost elements may vary from place to place in terms of their relative importance. In some cases fixed cost may be extremely high and operating cost relatively low.

To some extent we can view the route problem as one involving two extreme sets of goals.

q Least cost to build: to build the route or networks as cheaply as possible result in a network as low as possible.

q Least cost to users: to build the route or network with the aim of keeping the costs to the users as low as possible- result in highly connected route.

LECTURE 15

Cities as Service center

City

A city is a settlement with a large concentration of people with a distinctive organization, life-styles and livelihood. Specialized land uses and a variety of social, economic and political institutions allocate, coordinate and manage the resources found in the city. Cities are the center of power and control in our society.

Cities as a service center/function of a city

A principal function of the city is to provide services for its citizens and the surrounding hinterland (land behind the city/ service center from where it get supports).

These activities embrace a variety of services and management function like

v Retailing

v Banking

v Wholesaling

v Regional and national headquarters office activity

v Government services

v Various others personal and professional services

Hierarchical arrangement of the cities ( VERY IMPORTANT)

We can explain the hierarchical arrangement of the cities by using the theory of ‘Rank-Size Rule’.

One can predict the size of a given city by knowing its rank and the size of the largest city according to the following relationship

P_{n =}P₁ x 1/Rⁿ

P_n = population size of city being studied

P₁ = population size of largest city

Rⁿ= rank of city being studied

In this example the second largest city in a country should be one-half size of the largest city.

Composite centrality score

Measure of importance of a center in terms of population, function and other services.

Threshold population

Minimum requirement of population to sustain any service.

Trade area

Trade area is a sphere of influence over the area from which a service center draws its customers to buy goods and services.

Trade area should ideally extend from outward from the service center equally in all directions. But the shape and extent of this area can be modified/influenced by

v Competition with other centers

v Transportation accessibility

v Consumer preferences

Based as the principle of least effort, consumer, should travel to the nearest of the same size communities for a particular services.

The principles of least effort concept given by Zipf explained that persons seek the shortest distance and nearest alternative when choosing among routes and destinations.

Hinterland

Area from where products are delivered to the center.

Determining the trade area boundary ( VERY IMPORTANT)

Determining the trade area boundary between places unequal in size is more complex. Using gravity model approach, one can determine this boundary. The gravity model postulates that the potential power of attraction between two bodies increases with the product of their masses and decreases with distance between them.

The gravitational attraction of two places expressed as an example of ‘Interaction theory’, where economic interaction between two places varies positively according to their size and negatively according the intervening distance.

The theory is expressed in the following formula

I = P₁P₂/d

I = interaction

P₁ = population of one of the place

P₂ = population of other place

d = distance between them

Breaking point theory ( VERY IMPORTANT)

Provide a way to predict the location of the boundary line separating trade areas around two cities unequal in size.

BP = d/1+√Pop Z/Pop Y

BP = breaking point from the smaller trade center

d= distance between the two trade centers

Pop Z = population of largest city

Pop Y = population of smaller city

GEO 101 LECTURE SEGMENT 3

noreply@blogger.com (TANVIR) — Sun, 10 Jul 2011 14:26:00 +0600

LECTURE 6

Primitive Primary Economic Activities: ( VERY IMPORTANT)

Primitive Gathering

· Lowest order of economic activity.

· Only a few thousand people currently practice this form of livelihood.

· Primitive gathering is the oldest economic activities in which human being supported themselves by collecting a variety of products provided by nature.

· People collect fruits, nuts, barriers, roots leaves, and fiber from trees, shrubs and smaller plants.

· They plant few seeds and spend no time for cultivating the soils.

· They don’t try to improve and control their habitat.

· Gathering requires the least amount of capital investment and effort, but considerable space is required.

Location:

Isolated pockets in low latitudes areas, Amazon basin (Brazil, Peru, Ecuador and Venezuela)

Primitive Hunting ( VERY IMPORTANT)

· Primitive hunters share many characteristics with the primitive gatherers.

· Both group know how to use fire, prepare food, manufacture tools and implement the tools.

· Hunters know how to construct shelter.

· Both group generally don’t know domesticated food plants, domesticated animals and permanent settlement.

· Hunters differ from gatherers in that they employ more sophisticated methods to secure foods and depend much more on animals.

Location:

Occurs in high latitudes area, where temperature is very low and summer is very short.

Nomadic Herding ( VERY IMPORTANT)

· It is a more advanced economic activity than either gathering or hunting.

· They depend on domestication of animals.

· Animals supply food (milk, cheese and meat), materials for clothing (fibers and skin), shelter (skin), fuel (excrement) and tools (bones).

· Migration is a basic feature of this people.

· Nomads started the first economic activity.

· Started their activities near the river valley and started settled down.

· Started agriculture 15000 years ago near river valley.

Physical environment:

· Less precipitation area (mainly grassland)

· Grasses and shrubs comprise the natural vegetation.

LECTURE 7

Primary economic Activities

Primary economic activities are those economic activities by which Homo sapiens conduct economic activity to produce primary products.

Example:

Primary goods are also called tangible goods. These are mainly agricultural goods like rice, wheat, potatoes etc.

Characteristics:

We can identify primary economic activities by characterizing it in different pattern. The characteristics of primary economic activities are as follows:

· Primary activities are conducted by Homo sapiens to produce primary products.

· These are the products, which can be characterized by least processing and mass production directly from the field.

· Primary products fetch least price in the market.

· In primary economic activities net return may not be cost effective in some cases.

· Producers involved in these economic activities may remain poor.

· Primary economic activities belong to the production sector.

· Contribution to GDP from primary sector is less in developed countries (5%) and underdeveloped is about 60%-70%.

Different sectors of primary economic activities ( VERY IMPORTANT)

Ø Agriculture

Ø Mining

Ø Fishing

Ø Forestry

Ø Others

Agriculture

Growing of crops and raising of domesticated animals under human supervision.

Fishing

The harvesting of fish from fresh and salty water.

Mining

The extraction of minerals and natural resources from nature

Forestry

Cutting and collecting of timber/wood from natural or forest areas.

Fishing ( VERY IMPORTANT)

Fishing is a primary economic activity by which different types of fish are catches from water bodies. The production is bulk in size and in raw form.

Fish provide an important source of protein in the diet for much of the world’s population. For many parts of the third world, fish are the pre dominant source of high quality animal protein.

Water bodies:

There are two types of water bodies.

Ø Saline water bodies: ocean, sea, bay etc.

Ø Fresh water bodies: river, lake, pond, canal etc.

Most of the fish are found in saline water bodies.

Fishing ground

Fishing grounds are those spaces of the water body where most of the fish are found.

There are two types of fishing.

· Capture fishing: nature induced

· Culture fishing: man induced

Capture fishing: is that fishing activities where the fishermen only capture fish from natural water bodies without getting involved in maturing the fish.

Culture fishing: people culture/cultivate fish in man made water bodies.

Commercial fishing activity occurs predominantly in northern hemisphere ocean waters. Coastal margins of the middle latitudes are the biggest producing areas.

The largest producing areas for commercial fish are shallow waters on the continental shelf.

Biggest fishing ground situated near Peru, Chile and Argentina (South America: Capture fishing).

The total annual fish production of Bangladesh is estimated to be in the range of 1.5 to1.7 million tons. 2 million families directly dependent on fishing as their principal livelihood. But only 5 to 6 percent of the national GDP is from fisheries sector. Fisheries provide 60% of the animal protein intake of the entire population of the country.

Forestry ( VERY IMPORTANT)

Forestry is a primary economic activity by which people extract necessary things (wood, timber, leaves, honey etc.) from nature.

There are two types forest.

· Natural forest (nature induced)

· Social forest (man induced)

Timbering is the most widespread and dominant type of forestry activity.

Wood consumption occurs as fuel (cooking and heating users) and industrial purpose also.

Commercial forestry

Commercial forests occur in two huge global belts. The first virtually encircles the world in the higher latitudes of the northern hemisphere. Second forest gathering realm lies in the tropical equatorial zone, including a large part of South America and Central Africa.

There are two kinds of wood.

· Hard wood

· Soft wood

Hard wood is used for construction of houses, buildings, railway line, electric poles furniture etc.

Location: Hard wood is mainly found in the low latitude region (equatorial area). Most of the hard wood found in Amazon River valley.

Soft wood is mainly used for making paper, pulp etc.

Location: Soft wood is mainly found in high latitude area.

Mining ( VERY IMPORTANT)

Mining is a primary economic activity by which people extract minerals and natural resources from nature. Minerals mainly find in the parent Rock.

Rock

A compact and consolidated mass of mineral matter. Three types of rock are recognized: igneous, sedimentary and metamorphic.

There are 3 types of rock.

· Igneous rock

· Sedimentary rock

· Metamorphic rock

Igneous Rock

Rocks formed by solidification of molten magma either beneath (intrusive igneous rock) or at (extrusive igneous rocks) the Earth's surface.

Magma

Molten rock originating from the Earth's interior.

Sedimentary Rock

Rocks formed by the deposition, alteration and/or compression of weathered rock debris, chemical precipitates, or organic sediments.

Metamorphic Rock

A rock that forms from igneous, sedimentary or other metamorphic rocks through pressure increase, temperature rise, or chemical alteration.

Classification of minerals

· Hydrocarbons: crude oil, natural gas, coal

· Metallic Ores: iron, aluminum, copper, gold, silver, zinc etc.

Precious stones: diamond, ruby etc.

Parent rocks of hydrocarbons are mainly found in sedimentary rock.

Parent rocks of metallic ores are found in metamorphic and igneous rock. But mostly found in metamorphic rock.

But precious stone are only found in metamorphic rocks.

LECTURE 8 and 9

Agriculture ( VERY IMPORTANT)

Agriculture is very important, old and traditional type of primary economic activity. It is an economic activity conducted by Homo sapiens to grow crops and raise livestock directly from the field under their direct supervision.

Based on the mode of production, there are two types of agriculture

· Subsistence agriculture

· Commercial agriculture

Subsistence agriculture ( VERY IMPORTANT)

Subsistence agriculture is that type of agriculture practice by which farmers try to meet their own demand by producing the necessary agricultural products. There should not be any profit motive in producing those agricultural commodities. In other words subsistence agriculture is that where frequency of occurrence of crops raised from farmlands is about 1. We can also measure it through index of intensity of cropping. Country where population is less, index is about 1. There are two types of subsistence agriculture, such as

Ø Primitive agriculture/ Primitive subsistence agriculture

Ø Intensive agriculture/ Intensive subsistence agriculture

Primitive agriculture ( VERY IMPORTANT)

Primitive agriculture is the function of the south. It is also known as traditional agriculture. It manifests only rudimentary technical management of the land, and limited amounts of time, effort and capital are devoted to this activity. For example: shifting cultivation, slash/burn agriculture etc.

Intensive subsistence agriculture

When the farmers produce the goods in a cost effective manner it is known as intensive agriculture. The main objective of this agriculture is to gain profit by minimizing the cost. In this agriculture system frequency of occurrence of crops raised from farm is more than one.

Primitive agriculture is mainly different from intensive agriculture on the basis of

· Mode of production

· Cropping intensity

· Fragmentation of land

Mode of production: primitive subsistence agriculture is absolutely non-cost effective. There is no tendency to maximize the profit. On the other hand, intensive agriculture is cost-effective.

Cropping intensity: is a function of frequency of occurrence in a given year. For subsistence or primitive agriculture cropping intensity is single cropping.

But, in intensive agriculture the cropping intensity is double or multiple cropping.

Fragmentation of land: fragmentation of land is very low in primitive agriculture and on the other hand, very high in the intensive agriculture.

Commercial agriculture ( VERY IMPORTANT)

Commercial agriculture is mainly profit oriented or business oriented. These are also known as modern agriculture system.

Ø Commercial grain farming

Ø Plantation agriculture

Commercial grain farming

In commercial grain farming producers always produce the goods in a cost effective manner and make profit. All the equipments are mechanized. It is mainly seen in the north. Crops, which are produced in this agriculture system, are wheat, rice, corn etc.

Plantation agriculture

Plantation of tea, rubber, coffee, pineapple, coco tree known as plantation agriculture. Mainly it is the activity of south.

LECTURE 10

Secondary Economic Activities

Secondary economic activities are those activities by which Homo sapiens conduct economic activities to produce secondary products.

Example: secondary goods are also known as tangible goods. These are mainly industrial or manufactured goods.

Characteristics

The characteristics of secondary economic activities are as follows:

Ø Secondary economic activities belong to production sectors.

Ø Economic men conduct these activities to produce secondary goods.

Ø Secondary economic activities are mainly located in urban areas.

Ø These activities bring industrialization and also urbanization process.

Ø Secondary economic activities also activate tertiary economic activities.

Ø Products produced through secondary activities fetch more prices in the market place.

Components of secondary economic activities

( VERY IMPORTANT)There are three components of secondary economic activities. These are

v Manufacturing/Processing

v Energy production

v Construction

Manufacturing /Processing ( VERY IMPORTANT)

Manufacturing or processing is the key component of secondary economic activities. Manufacturing is the production of value added secondary products involving significant processing in manufacturing units. This is the process of converting raw materials into finished goods. These processing must be conducted in a cost effective manner. It entails maximization of profit and minimization of cost. Sustained manufacturing demand not only creates the demand for construction and energy but also increases demand for tertiary economic activities.

Construction activity ( VERY IMPORTANT)

Construction activity involves the construction of physical structures. For example: urban constructions like housing, markets, roads, bridges etc.

We can give the example of Jamuna Bridge. Construction of Jamuna Bridge leads to a better communication between Dhaka and north Bengal. This better communication leads to better infrastructure in the northern areas and cause decentralization of industries.

Energy production ( VERY IMPORTANT)

Secondary economic activities have set up a lot of industries. To run any industry the most essential input is energy.

Impact of Secondary economic Activity

Secondary economic activities are those economic activities from where we get secondary products and these products involve significant processing. Before the advent of industrial revolution there were no secondary economic activities. Secondary economic activity began with the transformation of nature-induced landscape to man induced landscapes. These economic activities start industrialization process and also urbanization process. This urbanization process causes migration of people from rural to urban areas. There is a re-distribution of population and majority of the people become the inhabitants of urban areas. Thus industrialization and urbanization occur that lead to overall development.

Basis of classification of industries

According to gross output/return ( VERY IMPORTANT FOR QUIZ)

v Large-scale industry

v Medium-scale industry

v Small-scale industry

v Cottage industry

Large-scale industries are those, which employ 100 or more workers and/or capital assets in excess of 300 million taka.

Medium scale industries are those, which provide employment for 50 to 99 workers and/or has fixed capital assets worth between 100 to 300 million taka.

Small scale industry are those, which employ less than 50 workers and/or has capital assets worth less than 100 million taka.

Cottage industries are those, which are very small-scale and are engaged in manufacturing activities mostly with family members.

According to input characteristics

· Land intensive (brick field)

· Labor intensive (garments, textile)

· Capital intensive (pharmaceuticals)

· Management intensive (IT sector)

· Technology intensive (IT sector)

According to output characteristics (composition of raw materials)

· Heavy industry (iron, steel)

· Medium industry (textile)

· Light industry (IT sector)

LECTURE 11

Tertiary economic activities

Tertiary economic activities are those economic activities by which Homo sapiens conduct economic activities to produce tertiary services. It is the biggest sector in a given economy.

Characteristics

The characteristics of tertiary economic activities are as follows:

v Tertiary activities are the service sector of the economy

v It is the exchange element of PCE mechanism

v These activities are mainly urban based

v Normally located in towns, cities, ports etc

v Tertiary economic activities provides value added services

v In developed countries this is the large sector contributing to GDP

Sectors involve in tertiary economic activities: ( VERY IMPORTANT)

ü Administration services

ü Wholesaling and retailing

ü Trade (international and internal)

ü Banking and financial services

ü Transportation services

ü Communication and information services

ü Utility services

ü Educational services

ü Health services

ü Recreation services

All tertiary economic activities are included in service sector, which provides all kinds of service to the public citizens.

Administrative services ( VERY IMPORTANT)

This sector includes both private and public sector activities. Public or government service people are appointed by the government to serve the people.

Judicial services are also included in administrative services. Magistrate is appointed for lower court by the government. Justices also appointed by the government for higher and Supreme Court.

Administrative and Judicial services are two main parts in administrative service in a given region or country. Administrators are totally responsible if anything happen in their region.

Health services ( VERY IMPORTANT)

Health and medical services mainly divided into two parts:

ü Curative services (help to get cured when people suffer any kind of diseases)

ü Preventive services (these services prevent people from becoming ill)

Utility services ( VERY IMPORTANT)

Utility services mainly found in urban areas. Electricity, gas, water and sewerage etc. are mainly known as utility services. Government or private sector may provide these services.

GEO 101 LECTURE SEGMENT 2

noreply@blogger.com (TANVIR) — Sun, 10 Jul 2011 14:14:00 +0600

LECTURE 3

Economic Man

Economic men are those Homo-Sapiens who are never satisfied with their present standard of living. In order to achieve a better standard of living and to achieve the goals they always try to engage themselves in maximum number of economic activities. They involve themselves in primary, secondary and tertiary activities. They always try to conduct their activities in a cost effective manner. The cost effective activities entail maximization of profit and minimization of cost.

Characteristics of Economic man:

· Almost 90% Homo Sapiens are Economic men.

· Economic men are not satisfied with their present standard of living.

· Try to involve economic activities to increase their income.

· Conduct their activities in a cost effective manner.

· Increase income so that they achieve better standard of living.

Origin of Homo Sapiens:

The planet earth is the only habitable place in the universe. It is habitable for living organisms.

The age of our planet earth is approximately 4.8 billion years.

2 millions years ago Homo-Sapiens first arrived in the Pleistocene period. At first they arrived at Kenya, Somalia and Ethiopia (Horn of Africa), Caucasus mountain area and Greater Mongolia.

The people of the Horn of Africa are called “Negroid”. Their skin is dark, curly hair, non-portruted nose, open lid eyes and are big in size.

The people of the Caucasus Mountain are called “Caucasoid”. Their have fair skin, curly hair, open lid eyes and are medium in size.

The people of the greater Mongolia are called “Mongoloids”. Their have yellow complexion, straight hair, semi open lid eyes and are small in size.

How natural landscape turn into cultural landscape ( VERY IMPORTANT) PLEASE SEE THIS DIAGRAM IN TSR

Secondary goods

Industry

Secondary goods

(foot wear)

Urbanization process

Natural

Landscape

Cultural landscape

Leather

Environmental degradation

Urbanization

Urbanization refers to a process in which an increasing proportion of an entire population lives in cities and the suburbs of the cities. Historically it has been closely connected with industrialization, when more and more sources of energy were used to enhance human productivity (industrialization), surplus increased in both agriculture and industry.

Secondary economic activity has a motion of industrialization leading to urbanization. Due to urbanization internal migration took place.

Economic men conduct various economic activities in cost effective manner. At first they do primary economic activities to survive. When they want to maximize their profit and to increase their income, they do secondary economic activities. In this stage they add additional value with their activities. These activities are held into a processing system of an industry. In this way industrialization is occurred. Therefore industrialization leads to urbanization. Internal migration (rural to urban) happen due to higher job opportunity, high wage rate and so on.

Finally natural landscape changed into cultural landscape and due to this environmental degradation occurred. We should try to mitigate this for a better environment.

LECTURE 4

Determinants of Economic activities (Nature Induced)

Determinants of Economic activities mean variables those determinants or help the economic activities. It is divided into two types

Natural (nature induced-created by mother nature)

Cultural (man induced created by man)

Temperature: ( VERY IMPORTANT)

The temperature near equator and near tropic is high. On the other hand, temperature in the temperate region and polar area is cool.

Wind pressure:( VERY IMPORTANT)

Wind pressure depends on temperature. When the temperature in the low latitude area is high, the atmosphere pressure is low. The more we go towards the pole the atmosphere pressure becomes high.

Wind system: ( VERY IMPORTANT)

The existence of wind pressure is responsible for the creation of wind system. In the low latitude region wind system is dominated by the monsoon.

Precipitation: ( VERY IMPORTANT)

Precipitation happens when there is a rainfall, snowfall or frost. In the tropical region when temperature is high, wind pressure is low precipitation occurred through rainfall.

River System: ( VERY IMPORTANT)

It creates a hydrological cycle, which is also known as water cycle. In this cycle when the sunray directly falls on riverbed the water gradually evaporated. It then goes up and forms cloud. When the clouds get heavier, it comes down the earth surface through precipitation.

Vegetation & Soils: ( VERY IMPORTANT)

In equatorial and tropical area soil are fertile due to climatic condition. So these areas are appropriate for the growth of natural vegetation. But if we go to the towards pole soil is not very good condition and the environment is not friendly also.

Determinants of Economic activities (Man Induced)

Man induced parameters are those economic parameters, which are created by economic man. We also call it cultural landscape. It is the function of different kinds of economic activities conducted by economic man. The secondary and tertiary economic activities are dominated by man induced parameters. So those regions, which are engaged in secondary and tertiary economic activities or has the influence of man induced parameters are the urbanized and the developed regions.

Socio-Economic:

Different types of socio-economic aspects give their influence to join or activate any kind of activity. The Income of the people has some difference according to their education and other related matters. Income and education also give their influence to creating social class.

Demographic:

Demographic parameters indicate people’s age, sex, and natural increase etc. parameters. Age and sex also give their influence on dependent and independent population of any society.

Historical:

Historical parameters influenced by different types of historical events of a nation. In our country we always try or like to follow our previous historical rules, which was introduced by British.

Political

Government policy to conduct or making any event has an important influence. These policies always help us to start or activate any kinds of activity.

LECTURE 5

PCE Mechanism

A DIAGRAM WHICH IS NOT VISIBLE HERE IS VERY IMPORTANT SO PLEASE HAVE LOOK ON TSR FOR THIS DIAGRAM

Earth as a whole is an accumulation of numerous market places for economic men. The tool of function in this market is a complex system named PCE mechanism.

PCE mechanism refers to any process that increases economic value of a commodity beyond the value of its raw materials inputs. PCE mechanism is an economic system under which economic men conduct their economic activities in a cost effective manner in the market place.

PCE mechanism is the combination of production, consumption and exchange regimes.

Producer produces goods & services to satisfy and meet the demand of the consumers.

Exchange mechanism works as a link between the producers and consumers by facilitating

· Investment

· Transportation

· Searching new market

This system is very much dependent on the consumers and their income as demand for quantity and variety of products depend on the income of the threshold population.

Threshold population of any PCE mechanism is given by the number of population weighted by their income (purchasing power).

Exchange refers to a process by which goods and services are transferred or traded from one location to another location where they have more worth to end users. This exchange is known to increase place utility of a commodity.

Form utility: the value of a commodity that attributed its form or physical characteristics.

Place utility: the worth of a commodity at a given location. Value is added by altering commodities from and place.

GEO 101 LECTURE 1 AND 2 SEGMENT 1

noreply@blogger.com (TANVIR) — Sun, 10 Jul 2011 14:06:00 +0600

Lecture :1

Geography: ( Definition is important for quiz and final and midterm)

Geography is the study of locational and spatial variation in natural and human phenomena on Earth.

Vidal de la Blache

Geography is the science of places, concerned with the qualities of potentialities of countries. The particuler character of a country is expressed by the totally of its feature, the social diversities associated with the diversities of places.Geography mainly divided into two parts.

Physical geography
Human geography

Physical geography:

Physical Geography focuses on geography as an Earth Science.It aims to understand the physical layout of the Earth.

Human geography:

Human Geography is a branch of geography that focuses on the study of patterns and processes that shape human interaction with various environments. It encompasses human, politiclal, cultural, social, and economic aspects. Economic Geography is one of the branch/part of Human Geography.

Economic geography:

is the study of the widely varying economic conditions across the earth. The economics of a geographical area can be influenced by climate, geology, and socio-political factors. Geology can affect resource availability, cost of transportation, and land use decisions. Climate can influence natural resource availability (particularly agriculture and forestry products), and working conditions and productivity. The social and political institutions that are unique to a region also have an impact on economic decisions.

Earth Surface

Atmosphere( important)

The atmosphere is the vast gaseous envelope of air that surrounds the Earth. Its boundaries are not easily defined. The atmosphere contains a complex system of gases and suspended particles that behave in many ways like fluids. Many of its constituents are derived from the Earth by way of chemical and biochemical reactions.

Hydrosphere(important)

The hydrosphere describes the waters of the Earth. Water of the hydrosphere exists in three states: liquid, solid and gaseous (water vapor). Water occurs in two general chemical conditions, fresh and salty. Water exists on the Earth in various stores, including the: atmosphere, oceans, lakes, rivers, glaciers, snowfields and groundwater. Water moves from one store to another by way of: evaporation, condensation, precipitation, deposition, runoff, infiltration, sublimation, transpiration, and groundwater flow.

Lithosphere (important)

Is the solid inorganic portion of the Earth (composed of rocks, minerals, and elements). It consists with crust and a portion of the upper mantle.

Biosphere (important)

Zone of the Earth where life is found. The biosphere consists of all living things, plant and animal. This zone is characterized by life in profusion, diversity, and ingenious complexity. Cycling of matter in this sphere involves not only metabolic reactions in organisms, but also many abiotic chemical reactions. Also called Ecosphere.

Earth's Atmosphere

The Earth is surrounded by a blanket of air, which we call the atmosphere. It reaches over 560 kilometers (348 miles) from the surface of the Earth, so we are only able to see what occurs fairly close to the ground. Early attempts at studying the nature of the atmosphere used clues from the weather, the beautiful multi-colored sunsets and sunrises, and the twinkling of stars. With the use of sensitive instruments from space, we are able to get a better view of the functioning of our atmosphere.

Life on Earth is supported by the atmosphere, solar energy, and our planet's magnetic fields. The atmosphere absorbs the energy from the Sun, recycles water and other chemicals, and works with the electrical and magnetic forces to provide a moderate climate. The atmosphere also protects us from high-energy radiation and the frigid vacuum of space.

The envelope of gas surrounding the Earth changes from the ground up. Four distinct layers have been identified using thermal characteristics (temperature changes), chemical composition, movement, and density.

Troposphere

The troposphere starts at the Earth's surface and extends 8 to 14.5 kilometers high (5 to 9 miles). This part of the atmosphere is the most dense. As you climb higher in this layer, the temperature drops from about 17 to -52 degrees Celsius. Almost all weather is in this region. The tropopause separates the troposphere from the next layer. The tropopause and the troposphere are known as the lower atmosphere.

Stratosphere

The stratosphere starts just above the troposphere and extends to 50 kilometers (31 miles) high. Compared to the troposphere, this part of the atmosphere is dry and less dense. The temperature in this region increases gradually to -3 degrees Celsius, due to the absorbtion of ultraviolet radiation. The ozone layer, which absorbs and scatters the solar ultraviolet radiation, is in this layer. Ninety-nine percent of "air" is located in the troposphere and stratosphere. The stratopause separates the stratosphere from the next layer.

Mesosphere

The mesosphere starts just above the stratosphere and extends to 85 kilometers (53 miles) high. In this region, the temperatures again fall as low as -93 degrees Celsius as you increase in altitude. The chemicals are in an excited state, as they absorb energy from the Sun. The mesopause separates the mesophere from the thermosphere.

The regions of the stratosphere and the mesosphere, along with the stratopause and mesopause, are called the middle atmosphere by scientists. This area has been closely studied on the ATLAS Spacelab mission series.

Thermosphere

The thermosphere starts just above the mesosphere and extends to 600 kilometers (372 miles) high. The temperatures go up as you increase in altitude due to the Sun's energy. Temperatures in this region can go as high as 1,727 degrees Celsius. Chemical reactions occur much faster here than on the surface of the Earth. This layer is known as the upper atmosphere.

The upper and lower layers of the thermosphere will be studied more closely during the Tethered Satellite Mission (TSS-1R).

Composition of the Atmosphere (important)

The atmosphere is primarily composed of Nitrogen (N₂, 78%), Oxygen (O₂, 21%), and Argon (Ar, 1%). A myriad of other very influential components are also present which include the water (H₂O, 0 - 7%), "greenhouse" gases or Ozone (O<SUB3< SUB>, 0 - 0.01%), Carbon Dioxide (CO₂, 0.01-0.1%),

Beyond the Atmosphere

The exosphere starts at the top to the thermosphere and continues until it merges with interplanetary gases, or space. In this region of the atmosphere, Hydrogen and Helium are the prime components and are only present at extremely low densities.

Relatively thin life-supporting stratum of the Earth's surface, extending from a few kilometres into the atmosphere to the deep-sea vents of the ocean. The biosphere is a global ecosystem composed of living organisms (biota) and the abiotic (nonliving) factors from which they derive energy and nutrients.

MANAGEMENT 211

noreply@blogger.com (TANVIR) — Fri, 8 Jul 2011 19:16:00 +0600

CHAPTER 1
INTRODUCTION TO MANAGEMENT AND ORGANIZATION
MANGER
Manager is the man who manages everything in an organization. In other words manager is someone who works with other people and through other people and co ordinate their work activities to accomplish organizational goals. (Mana manger holo amon akjon mansuh ja onnoder kajer somonnoy kora organizational goal achieve kora.
There are 3 types of manager

1. First line manager: are low level manager who mange the work of non managerial employee and directly involve with production. Such as supervisor or foreman.

2. Middle manager: are the managers between first line and top level manager. They manage the work or supervise first line manager.

3. Top managers: are the managers who supervise the work of first line and middle managers. They make the organization top decisions and they take the responsibility for those decision.

Management: means co coordinating work activities so that they are done efficiently and effectively.
Efficiency: getting most output with the list amount of input. Doing the things right ( shothikbhaba kaj kora) .
Effectiveness: completing activities so that organizational goals are attained. Doing the things right. ( shothik kaj kora)
Function of management

1. Planning: planning involve determining goals and establishing strategies to achieve those goals.

2. Organizing: involve what tasks are to be done, who will do the task, who will report to whom and where decision will take place.

3. Leading: involve motivating co workers, influencing individual to work, selecting the most effective communication channel.

4. Controlling: involve monitoring actual performance and taking action if necessary.

Management roles: there are 3 types of managerial roles.

1. Interpersonal: involving people and other duties that are symbolic in nature. Interpersonal roles are divided into 3 types.

· Figure head: perform number of routine duties. Such as signing in the legal document

· Leader: responsible for motivating co workers, training and staffing. Such as performing virtually all activities that involve all subordinates.

· Liaison: maintaining contact with others. Such as doing external work that includes outsiders.

2. Informational roles: role includes receiving and collecting information. This role divides into 3 steps.

· Monitor: seeking internal and external information to develop organization.

· Disseminator: receive information from or from co workers. Such as holding informational meeting.

· Spokesperson: give information to outsider. Such as holding broad meeting and giving it to media.

3. Decisional roles: roles involve making choices. This role is divided into 4 parts.

· Entrepreneur: search organizations and its environment for opportunities. Such as make organization strategy to develop new programmed

· Disturbance handler: responsible to control unexpected disturbance. Such as think if any accident or any unexpected activities done by a brac student before its campus then brac university authority will take the responsibility

· Resources allocator (sompodaror resources ar botton): responsible for allocating resources of the organization.

· Negotiator: responsible for representing the organization at major negotiations.

Managerial skill:
Managerial skill are divided into 3 steps

1. Human skill : working ability with other people individually or in a group

2. Technical skill: knowledge and proficiency in specialized field.

3. Conceptual skill: the ability to think and conceptualized about complex.

Organization
A deliberate arrangement of people to accomplish some specific purpose. (mana serialy organization ar manushder sajano for some specific purpose.

CHAPTER 8

STRATEGIC MANAGEMENT

Strategic management:

Strategic management is a set of managerial decision which meets the long run performance of an organization.

Importance of Strategic management:

Strategic management can make differences in organization performance.
To cope up with the changing situation manger examine different variables to take decision.
Strategic management is also important to achieving organizational goals by co coordinating different division, units, functions and work activities.
Finally, strategic management is important because it involve many decisions that managers make.

Strategic management process:

Strategic management is six step processes that encompass strategic planning, implementing and evaluating.

Step 1 : identifying organizations current mission, objective and strategies:

Every organization needs a mission – statement of the purpose of an organization. Organization mission forces manager to carefully identify the scope of its products and services. It is also for a manager to know organization goals. Because we all know that goal setting is the foundation of planning. Knowing the current mission of organization and assessing them manager will decide whether these goals need to be changed or not. For the same reason it is important for mangers to identify the organizations current strategies.

External analysis :

External analysis is an important constraint (baddho kora) on a manger action. External analysis is important to know what competition is going on, what are affecting organization and giving opportunities to organization. In analyzing external environment mangers need to examine both specific and general environment to see what trend and changes are occurring. After analyzing external environment manager must identify what are opportunities the organization have and what are the threats that organization should counteract.

internal analysis ;

In internal analysis manger assess the resources and capabilities of an organization. Any activities organization do well is unique in the organization and any activity organization does not do well is weakness.

Internal analysis provides important information about organizational resources and capabilities. If any of these organizational resources are unique they are called organization core competency. The combined internal and external analysis is called S.W.O.T analysis.

Formulating strategies :

After S.W.O.T analysis is over manager should select the appropriate strategies for all level in the organization. Manager also should matches organization strength to environment opportunities and correct weakness and guard against thread to meet the rival (protijogi).

Implementation strategy :

After formulating strategy must be implement properly. Otherwise strategy will not going to work.

Evaluating strategy :

Final step in the management strategy process is evaluating. How effective the strategy been and what adjustment is needed in the strategy.

Types of organizations strategy:

corporate level strategy: refers that what business a company should do or wants to be in and it also reflect that in which direction organization is going and what roles that each organization is pursuing to reach that direction ( mana holo akta organization ar ki ki bussines kora uchit or kon business a dhuka uchit and organization kon dika jaccha ar organization ar each unit oy direction a jabar jonno ki ki role play kortasa). Corporate level strategies are 3 types.

Growth strategy: is a corporate level strategy seeks to increase the organization operation by expanding the number of product and services offered or market served. ( mana product ar services bariya organization ar operation increase kora).
Stability strategy: is a corporate level strategy characterized by an absence of significant change ( mana kono dhoronar new product offer korba na). Such as offering same product and services to same clients.
Renewal strategy: is a corporate level strategy designed to address or meet organization weakness for what organization performances are declining. ( mana ay strategy dara organization ar weakness meet kora hoy). Renewal strategies are 2 types.

1. Retrenchment strategy: a short run renewal strategy. This strategy implanted in organization when problem is not so serious.

2. Turnaround strategy: is a strategy which in the organization when the problem is serious or critical.

Corporate portfolio analysis: when a organization corporate strategy involves in a number of business, manager can manage this portfolio of business using a corporate portfolio matrix. The first portfolio matrix developed by Boston consultancy group( BCG)

Based on corporate analysis business can be evaluated in to 4 categories.

Cash cows (low growth, high market share): business generate huge amount of money but the business growth is limited.
stars ( high growth, high market share): business in this category generate huge amount of money and business growth is also high
Question marks (high growth, low market share): business in the category growth very high but they generate a small amount of money as a result their market is low.
Dogs (low growth, low market share): in this category business do not generate much cash and then don’t provide promises for improving performance.

Business level strategy: an organization strategy seeks to determine how organization will compete each of its business. For organization in multiple business.

Competitive advantage: what sets an organization apart, that is, its distinct edge? ( mana kono unique resources or capabilities make organization different from other)
Sustainable competitive advantage : sustainable advantage enable the organization to despite competitor action or evolutionary changes in the business.

· competitive strategy :

1. threats of new entrance

2. bargaining power of buyers

3. burgainig power of supplier

4. current rivalry

· Cost leadership strategy : a business level stategy when an organization in the market is the low cost producer

· Differentiation strategy: in which a company offered unique product which is valued by customers. Such as SONY

· Focus strategy: a business level strategy in which a company pursues cost or differentiation advantages in narrow industry segment.

Stuck in the middle: a situation when a company cant develop low cost or differentiation advantages.

3. Functional level strategy: an organization strategy that support business level straegy.