bLoG oF kNoWlEdGe

Hydrogen Fuel Cell

2010-11-24T00:45:00.000-08:00

The hydrogen fuel cell operates similar to a battery. It has two electrodes, an anode and a cathode, separated by a membrane. Oxygen passes over one electrode and hydrogen over the other.

The hydrogen reacts to a catalyst on the electrode anode that converts the hydrogen gas into negatively charged electrons (e-) and positively charged ions (H+).

The electrons flow out of the cell to be used as electrical energy. The hydrogen ions move through the electrolyte membrane to the cathode electrode where they combine with oxygen and the electrons to produce water. Unlike batteries, fuel cells never run out.

Latest Automotive Technologies To Help You While Driving

2010-11-18T00:34:00.000-08:00

In-car Journey recorder - Nikkai has designed an "In-Car Journey Recorder" to be placed on the inside of your windshield. The journey recorder is a video recorder which records the road in front of your car during your travels. This might seem like a really useless device, but Nikkai designed the journey recorder to help record events in case of a car accident. This helps your insurance assess liability, while it helps your case if the person you have an accident with disputes your telling of the story. If a civil lawsuit or criminal case comes down to your word against theirs, you have the big hammer of a recorded event to back up your version of the wreck. I like this device.
Travolution from Audi - Audi is working on a device they call the "travolution", which is something I wish I had the money to afford. Apparently, the Travolution device lets you know how long it will be until a stoplight turns. For instance, if you are speeding towards a light and you're afraid it's going to turn red, the Travolution device lets you know how long it will be until the light turns, and whether you can keep speeding. Also, if you've been sitting at a light for an interminable time and you're starting to blow your fuse, the certainty of knowing how long you must maintain your patience is important (at least it would be for me).
Eco-friendly dashboards - Ford Motors announced in early 2009 an ecological-friendly dashboard, which is designed to tell you when you are wasting precious resources and when you are behaving in an ecologically-acceptable way. Obviously, you probably know if you're behaving in a conservation-friendly manner, but I guess every little bit helps. Other car designers, like Honda (Insight) and Toyota (Prius) have similar features on certain models. Strangely, instead of a statistical reminder of warning light, this dashboard has a green vine that grows when you are behaving, and the vine whithers when you are wasting energy resources. I presume that this vine feature is designed to be recognizable in the international market that Ford is trying market to, because pictures and symbols are easier to understand than a particular language.

Source : http://www.askdeb.com/technology/automotive/

Nanoparticles could deliver multi-drug therapy to tumors..

2010-11-14T20:54:00.001-08:00

By Rice University, [RxPG] In the ongoing search for better ways to target anticancer drugs to kill tumors without making people sick, researchers find that nanoparticles called buckyballs might be used to significantly boost the payload of drugs carried by tumor-targeting antibodies.

In research due to appear in an upcoming issue of the journal Chemical Communications, scientists at Rice University and The University of Texas M. D. Anderson Cancer Center describe a method for creating a new class of anti-cancer compounds that contain both tumor-targeting antibodies and nanoparticles called buckyballs. Buckyballs are soccer ball-shaped molecules of pure carbon that can each be loaded with several molecules of anticancer drugs like Taxol®.

In the new research, the scientists found they could load as many as 40 buckyballs into a single skin-cancer antibody called ZME-018. Antibodies are large proteins created by the immune system to target and attack diseased or invading cells.

Previous work at M. D. Anderson has shown that ZME-018 can be used to deliver drugs directly into melanoma tumors, and work at Rice has shown that Taxol can be chemically attached to a buckyball.

"The idea that we can potentially carry more than one Taxol per buckyball is exciting, but the real advantage of fullerene immunotherapy over other targeted therapeutic agents is likely to be the buckyball's potential to carry multiple drug payloads, such as Taxol plus other chemotherapeutic drugs," said Rice's Lon Wilson, professor of chemistry. "Cancer cells can become drug resistant, and we hope to cut down on the possibility of their escaping treatment by attacking them with more than one kind of drug at a time."

Researchers have long dreamed of using antibodies like ZME-018 to better target chemotherapy drugs like Taxol, and M. D. Anderson's Michael G. Rosenblum, Ph.D., professor in the Department of Experimental Therapeutics and Chief of the Immunopharmacology and Targeted Therapy Laboratory, has conducted some of the pioneering work in this field.

"This is an exciting opportunity to apply novel materials such as fullerenes to generate targeted therapeutics with unique properties," Rosenblum said. "If successful, this could usher in a new class of agents for therapy not only for cancer, but for other diseases as well."

While it's possible to attach drug molecules directly to antibodies, Wilson said scientists haven't been able to attach more than a handful of drug molecules to an antibody without significantly changing its targeting ability. That happens, in large part, because the chemical bonds that are used to attach the drugs -- strong, covalent bonds -- tend to block the targeting centers on the antibody's surface. If an antibody is modified with too many covalent bonds, the chemical changes will destroy its ability to recognize the cancer it was intended to attack.

Wilson said the team from Rice and M. D. Anderson had planned to overcome this limitation by attaching multiple molecules of Taxol to each buckyball, which would then be covalently connected to the antibodies. To the team's surprise, many more buckyballs than expected attached themselves to the antibody. Moreover, no covalent bonds were required, so the increased payload did not significantly change the targeting ability of the antibody.

Wilson said certain binding sites on the antibody are hydrophobic (water repelling), and the team believes that these hydrophobic sites attract the hydrophobic buckyballs in large numbers so multiple drugs can be loaded into a single antibody in a spontaneous manner to give the antibody-drug agent more "bang for the buck."

"The use of these nanomaterials solves some intractable problems in targeted therapy and additionally demonstrates the increasing value of the team science approach bridging different disciplines to uniquely address existing problems," Rosenblum said.

Source : http://www.rxpgnews.com/nanotechnology/Nanoparticles_could_deliver_multi-drug_therapy_to__4527_4527.shtml

Cloud Computing...

2010-11-14T02:47:00.000-08:00

Cloud computing is Web-based processing, whereby shared resources, software, and information are provided to computers and other devices (such as smartphones) on demand over the Internet.

Cloud computing is a paradigm shift following the shift from mainframe to client–server in the early 1980s. Details are abstracted from the users, who no longer have need for expertise in, or control over, the technology infrastructure "in the cloud" that supports them. Cloud computing describes a new supplement, consumption, and delivery model for IT services based on the Internet, and it typically involves over-the-Internet provision of dynamically scalable and often virtualized resources. It is a byproduct and consequence of the ease-of-access to remote computing sites provided by the Internet. This frequently takes the form of web-based tools or applications that users can access and use through a web browser as if it were a program installed locally on their own computer. NIST provides a somewhat more objective and specific definition here. The term "cloud" is used as a metaphor for the Internet, based on the cloud drawing used in the past to represent the telephone network, and later to depict the Internet in computer network diagrams as an abstraction of the underlying infrastructure it represents. Typical cloud computing providers deliver common business applications online that are accessed from another Web service or software like a Web browser, while the software and data are stored on servers.

Most cloud computing infrastructures consist of services delivered through common centers and built on servers. Clouds often appear as single points of access for consumers' computing needs. Commercial offerings are generally expected to meet quality of service (QoS) requirements of customers, and typically include service level agreements (SLAs). The major cloud service providers include Salesforce, Amazon and Google. Some of the larger IT firms that are actively involved in cloud computing are Fujitsu, Microsoft, Hewlett Packard, IBM, VMware and Dell.

Comparisons

Cloud computing derives characteristics from, but should not be confused with:

Autonomic computing — "computer systems capable of self-management"
Client–server model – client–server computing refers broadly to any distributed application that distinguishes between service providers (servers) and service requesters (clients)
Grid computing — "a form of distributed computing and parallel computing, whereby a 'super and virtual computer' is composed of a cluster of networked, loosely coupled computers acting in concert to perform very large tasks"
Mainframe computer — powerful computers used mainly by large organizations for critical applications, typically bulk data-processing such as census, industry and consumer statistics, enterprise resource planning, and financial transaction processing.
Utility computing — the "packaging of computing resources, such as computation and storage, as a metered service similar to a traditional public utility, such as electricity";
Peer-to-peer – distributed architecture without the need for central coordination, with participants being at the same time both suppliers and consumers of resources (in contrast to the traditional client–server model)

Characteristics

Generally, cloud computing customers do not own the physical infrastructure, instead avoiding capital expenditure by renting usage from a third-party provider. They consume resources as a service and pay only for resources that they use. Many cloud-computing offerings employ the utility computing model, which is analogous to how traditional utility services (such as electricity) are consumed, whereas others bill on a subscription basis. Sharing "perishable and intangible" computing power among multiple tenants can improve utilization rates, as servers are not unnecessarily left idle (which can reduce costs significantly while increasing the speed of application development). A side-effect of this approach is that overall computer usage rises dramatically, as customers do not have to engineer for peak load limits. In addition, "increased high-speed bandwidth" makes it possible to receive the same. The cloud is becoming increasingly associated with small and medium enterprises (SMEs) as in many cases they cannot justify or afford the large capital expenditure of traditional IT. SMEs also typically have less existing infrastructure, less bureaucracy, more flexibility, and smaller capital budgets for purchasing in-house technology. Similarly, SMEs in emerging markets are typically unburdened by established legacy infrastructures, thus reducing the complexity of deploying cloud solutions.

Economics

Cloud computing users avoid capital expenditure (CapEx) on hardware, software, and services when they pay a provider only for what they use. Consumption is usually billed on a utility (resources consumed, like electricity) or subscription (time-based, like a newspaper) basis with little or no upfront cost. Other benefits of this approach are low barriers to entry, shared infrastructure and costs, low management overhead, and immediate access to a broad range of applications. In general, users can terminate the contract at any time (thereby avoiding return on investment risk and uncertainty), and the services are often covered by service level agreements (SLAs) with financial penalties.

According to Nicholas Carr, the strategic importance of information technology is diminishing as it becomes standardized and less expensive. He argues that the cloud computing paradigm shift is similar to the displacement of electricity generators by electricity grids early in the 20th century.

Although companies might be able to save on upfront capital expenditures, they might not save much and might actually pay more for operating expenses. In situations where the capital expense would be relatively small, or where the organization has more flexibility in their capital budget than their operating budget, the cloud model might not make great fiscal sense. Other factors impacting the scale of any potential cost savings include the efficiency of a company's data center as compared to the cloud vendor's, the company's existing operating costs, the level of adoption of cloud computing, and the type of functionality being hosted in the cloud.

Among the items that some cloud hosts charge for are instances (often with extra charges for high-memory or high-CPU instances); data transfer in and out; storage (measured by the GB-month); I/O requests; PUT requests and GET requests; IP addresses; and load balancing. In some cases, users can bid on instances, with pricing dependent on demand for available instances.

Architecture

Cloud computing sample architecture

Cloud architecture,^[26] the systems architecture of the software systems involved in the delivery of cloud computing, typically involves multiple cloud components communicating with each other over application programming interfaces, usually web services. This resembles the Unix philosophy of having multiple programs each doing one thing well and working together over universal interfaces. Complexity is controlled and the resulting systems are more manageable than their monolithic counterparts.

The two most significant components of cloud computing architecture are known as the front end and the back end. The front end is the part seen by the client, i.e. the computer user. This includes the client’s network (or computer) and the applications used to access the cloud via a user interface such as a web browser. The back end of the cloud computing architecture is the ‘cloud’ itself, comprising various computers, servers and data storage devices.

Key features

Agility improves with users' ability to rapidly and inexpensively re-provision technological infrastructure resources.
Cost is claimed to be greatly reduced and capital expenditure is converted to operational expenditure. This ostensibly lowers barriers to entry, as infrastructure is typically provided by a third-party and does not need to be purchased for one-time or infrequent intensive computing tasks. Pricing on a utility computing basis is fine-grained with usage-based options and fewer IT skills are required for implementation (in-house).
Device and location independence enable users to access systems using a web browser regardless of their location or what device they are using (e.g., PC, mobile). As infrastructure is off-site (typically provided by a third-party) and accessed via the Internet, users can connect from anywhere.
Multi-tenancy enables sharing of resources and costs across a large pool of users thus allowing for:
- Centralization of infrastructure in locations with lower costs (such as real estate, electricity, etc.)
- Peak-load capacity increases (users need not engineer for highest possible load-levels)
- Utilization and efficiency improvements for systems that are often only 10–20% utilized.
Reliability is improved if multiple redundant sites are used, which makes well designed cloud computing suitable for business continuity and disaster recovery. Nonetheless, many major cloud computing services have suffered outages, and IT and business managers can at times do little when they are affected.
Scalability via dynamic ("on-demand") provisioning of resources on a fine-grained, self-service basis near real-time, without users having to engineer for peak loads. Performance is monitored, and consistent and loosely coupled architectures are constructed using web services as the system interface. One of the most important new methods for overcoming performance bottlenecks for a large class of applications is data parallel programming on a distributed data grid.
Security could improve due to centralization of data, security-focused resources, etc., but concerns can persist about loss of control over certain sensitive data, and the lack of security for stored kernels. Security is often as good as or better than under traditional systems, in part because providers are able to devote resources to solving security issues that many customers cannot afford. Providers typically log accesses, but accessing the audit logs themselves can be difficult or impossible. Furthermore, the complexity of security is greatly increased when data is distributed over a wider area and / or number of devices.
Maintenance of cloud computing applications is easier, since they don't have to be installed on each user's computer. They are easier to support and to improve since the changes reach the clients instantly.
Metering means that cloud computing resources usage should be measurable and should be metered per client and application on a daily, weekly, monthly, and yearly basis.

Layers

Client

A cloud client consists of computer hardware and/or computer software that relies on cloud computing for application delivery, or that is specifically designed for delivery of cloud services and that, in either case, is essentially useless without it. Examples include some computers, phones and other devices, operating systems and browsers.

Application

Cloud application services or "Software as a Service (SaaS)" deliver software as a service over the Internet, eliminating the need to install and run the application on the customer's own computers and simplifying maintenance and support. People tend to use the terms ‘SaaS’ and ‘cloud’ interchangeably, when in fact they are 2 different things. Key characteristics include:

Network-based access to, and management of, commercially available (i.e., not custom) software
Activities that are managed from central locations rather than at each customer's site, enabling customers to access applications remotely via the Web
Application delivery that typically is closer to a one-to-many model (single instance, multi-tenant architecture) than to a one-to-one model, including architecture, pricing, partnering, and management characteristics
Centralized feature updating, which obviates the need for downloadable patches and upgrades.

Platform

Cloud platform services or "Platform as a Service (PaaS)" deliver a computing platform and/or solution stack as a service, often consuming cloud infrastructure and sustaining cloud applications.^[53] It facilitates deployment of applications without the cost and complexity of buying and managing the underlying hardware and software layers.

Infrastructure

Cloud infrastructure services, also known as "Infrastructure as a Service (IaaS)", delivers computer infrastructure - typically a platform virtualization environment - as a service. Rather than purchasing servers, software, data-center space or network equipment, clients instead buy those resources as a fully outsourced service. Suppliers typically bill such services on a utility computing basis and amount of resources consumed (and therefore the cost) will typically reflect the level of activity. IaaS evolved from virtual private server offerings.

Server

The servers layer consists of computer hardware and/or computer software products that are specifically designed for the delivery of cloud services, including multi-core processors, cloud-specific operating systems and combined offerings.

Source : http://en.wikipedia.org/wiki/Cloud_computing

Windows 7 the latest Windows

2010-11-14T02:14:00.000-08:00

Windows 7 is the latest release of Microsoft Windows, a series of operating systems produced by Microsoft for use on personal computers, including home and business desktops, laptops, netbooks, tablet PCs, and media center PCs. Windows 7 was released to manufacturing on July 22, 2009, and reached general retail availability on October 22, 2009, less than three years after the release of its predecessor, Windows Vista. Windows 7's server counterpart, Windows Server 2008 R2, was released at the same time.

Unlike its predecessor, Windows Vista, which introduced a large number of new features, Windows 7 was intended to be a more focused, incremental upgrade to the Windows line, with the goal of being compatible with applications and hardware which Windows Vista was not at the time. Presentations given by Microsoft in 2008 focused on multi-touch support, a redesigned Windows shell with a new taskbar, referred to as the Superbar, a home networking system called HomeGroup, and performance improvements. Some standard applications that have been included with prior releases of Microsoft Windows, including Windows Calendar, Windows Mail, Windows Movie Maker, and Windows Photo Gallery, are not included in Windows 7; most are instead offered separately at no charge as part of the Windows Live Essentials suite.

Development

Originally, a version of Windows codenamed Blackcomb was planned as the successor to Windows XP (codename Whistler) and Windows Server 2003. Major features were planned for Blackcomb, including an emphasis on searching and querying data and an advanced storage system named WinFS to enable such scenarios. However, an interim, minor release, codenamed "Longhorn," was announced for 2003, delaying the development of Blackcomb. By the middle of 2003, however, Longhorn had acquired some of the features originally intended for Blackcomb. After three major viruses exploited flaws in Windows operating systems within a short time period in 2003, Microsoft changed its development priorities, putting some of Longhorn's major development work on hold while developing new service packs for Windows XP and Windows Server 2003. Development of Longhorn (Windows Vista) was also restarted, and thus delayed, in August 2004. A number of features were cut from Longhorn.

Blackcomb was renamed Vienna in early 2006 and again Windows 7 in 2007. In 2008, it was announced that Windows 7 would also be the official name of the operating system. There has been some confusion over naming the product Windows 7, while versioning it as 6.1 to indicate its similar build to Vista and increase compatibility with applications that only check major version numbers, similar to Windows 2000 and Windows XP both having 5.x version numbers.

The first external release to select Microsoft partners came in January 2008 with Milestone 1, build 6519. At PDC 2008, Microsoft demonstrated Windows 7 with its reworked taskbar. Copies of Windows 7 build 6801 were distributed at the end of the conference; however, the demonstrated taskbar was disabled in this build.

On December 27, 2008, the Windows 7 Beta was leaked onto the Internet via BitTorrent. According to a performance test by ZDNet, Windows 7 Beta beat both Windows XP and Vista in several key areas; including boot and shutdown time and working with files, such as loading documents. Other areas did not beat XP; including PC Pro benchmarks for typical office activities and video editing, which remain identical to Vista and slower than XP. On January 7, 2009, the 64-bit version of the Windows 7 Beta (build 7000) was leaked onto the web, with some torrents being infected with a trojan. At CES 2009, Microsoft CEO Steve Ballmer announced the Windows 7 Beta, build 7000, had been made available for download to MSDN and TechNet subscribers in the format of an ISO image. The Beta was to be publicly released January 9, 2009, and Microsoft initially planned for the download to be made available to 2.5 million people on this date. However, access to the downloads was delayed because of high traffic. The download limit was also extended, initially until January 24, then again to February 10. People who did not complete downloading the beta had two extra days to complete the download. After February 12, unfinished downloads became unable to complete. Users could still obtain product keys from Microsoft to activate their copies of Windows 7 Beta, which expired on August 1, 2009.

The release candidate, build 7100, became available for MSDN and TechNet subscribers and Connect Program participants on April 30, 2009. On May 5, 2009 it became available to the general public, although it had also been leaked onto the Internet via BitTorrent. The release candidate was available in five languages and expired on June 1, 2010, with shutdowns every two hours starting March 1, 2010. Microsoft stated that Windows 7 would be released to the general public on October 22, 2009. Microsoft released Windows 7 to MSDN and Technet subscribers on August 6, 2009, at 10:00 a.m. PDT. Microsoft announced that Windows 7, along with Windows Server 2008 R2, was released to manufacturing on July 22, 2009. Windows 7 RTM is build 7600.16385, which was compiled on July 13, 2009, and was declared the final RTM build after passing all Microsoft's tests internally.

Windows NT is written in C, C++, and assembly.

Features

Windows 7 includes a number of new features, such as advances in touch and handwriting recognition, support for virtual hard disks, improved performance on multi-core processors,^[38]^[39]^[40]^[41] improved boot performance, DirectAccess, and kernel improvements. Windows 7 adds support for systems using multiple heterogeneous graphics cards from different vendors (Heterogeneous Multi-adapter), a new version of Windows Media Center, a Gadget for Windows Media Center, improved media features, the XPS Essentials Pack and Windows PowerShell being included, and a redesigned Calculator with multiline capabilities including Programmer and Statistics modes along with unit conversion. Many new items have been added to the Control Panel, including ClearType Text Tuner, Display Color Calibration Wizard, Gadgets, Recovery, Troubleshooting, Workspaces Center, Location and Other Sensors, Credential Manager, Biometric Devices, System Icons, and Display. Windows Security Center has been renamed to Windows Action Center (Windows Health Center and Windows Solution Center in earlier builds), which encompasses both security and maintenance of the computer. Readyboost on 32bit editions now supports up to 256 Gigabytes of extra allocation. The default setting for User Account Control in Windows 7 has been criticized for allowing untrusted software to be launched with elevated privileges without a prompt by exploiting a trusted application.Microsoft's Windows kernel engineer Mark Russinovich acknowledged the problem, but noted that malware can also compromise a system when users agree to a prompt. Windows 7 also supports images in the RAW image format through the addition of Windows Imaging Component-enabled image decoders, which enables raw image thumbnails, previewing and metadata display in Windows Explorer, plus full-size viewing and slideshows in Windows Photo Viewer and Window Media Center.

The taskbar has seen the biggest visual changes, where the Quick Launch toolbar has been replaced with the "Superbar" allowing applications to be pinned to the taskbar. Buttons for pinned applications are integrated with the task buttons. These buttons also enable the Jump Lists feature to allow easy access to common tasks. The revamped taskbar also allows the reordering of taskbar buttons. To the far right of the system clock is a small rectangular button that serves as the Show desktop icon. This button is part of the new feature in Windows 7 called Aero Peek. Hovering over this button makes all visible windows transparent for a quick look at the desktop. In touch-enabled displays such as touch screens, tablet PCs, etc., this button is slightly wider to accommodate being pressed with a finger. Clicking this button minimizes all windows, and clicking it a second time restores them. Additionally, there is a feature named Aero Snap, that automatically maximizes a window when it is dragged to the top of the screen. Dragging windows to the left/right edges of the screen allows users to snap documents or files on either side of the screen for comparison between windows. When a user moves windows that were maximized using Aero Snap, the system restores their previous state automatically. This functionality is also accomplished with keyboard shortcuts. Unlike in Windows Vista, window borders and the taskbar do not turn opaque when a window is

Hardware requirements

Microsoft has published the minimum specifications for a system to run Windows 7.Requirements for the 32-bit version are similar to that of premium editions of Vista, but are higher for 64-bit versions. Microsoft has released an upgrade advisor that determines if a computer is compatible with Windows 7. Although the Nvidia GeForce FX (5xxx) series graphics cards meet the minimum hardware requirement, nVidia has decided not to produce Windows 7 compatible drivers for anything below the GeForce 6 Series.

Minimum hardware requirements for Windows 7
Architecture	32-bit	64-bit
Processor	1 GHz x86 processor	1 GHz x86-64 processor
Memory (RAM)	1 GB	2 GB
Graphics Card	DirectX 9 graphics processor with WDDM driver model 1.0 (Not absolutely necessary; only required for Aero)
HDD free space	16 GB of free disk space	20 GB of free disk space
Optical drive	DVD drive (only to install from DVD/CD Media)

Additional requirements to use certain features:

Windows XP Mode (Professional, Ultimate and Enterprise): Requires an additional 1GB of RAM and additional 15GB of available hard disk space. The requirement for a processor capable of hardware virtualization has been lifted.
Windows Media Center (included in Home Premium, Professional, Ultimate and Enterprise), requires a TV tuner to receive and record TV

Source: http://en.wikipedia.org/wiki/Windows_7

Concept car that Runs on AIR.....

2008-02-13T07:16:00.000-08:00

An engineer has promised that within a year he will start selling a car that runs on compressed air, producing no emissions at all in town.
The OneCAT will be a five-seater with a glass fibre body, weighing just 350kg and could cost just over £2,500.
It will be driven by compressed air stored in carbon-fibre tanks built into the chassis.
The tanks can be filled with air from a compressor in just three minutes - much quicker than a battery car.
Alternatively, it can be plugged into the mains for four hours and an on-board compressor will do the job.
For long journeys the compressed air driving the pistons can be boosted by a fuel burner which heats the air so it expands and increases the pressure on the pistons. The burner will use all kinds of liquid fuel.
The designers say on long journeys the car will do the equivalent of 120mpg. In town, running on air, it will be cheaper than that.
"The first buyers will be people who care about the environment," says French inventor Guy Negre.
"It also has to be economical."
Major savings
Mr Negre has been promising for more than a decade to be on the verge of a breakthrough. Independent observers are more convinced this time because he recently secured backing from the giant Indian conglomerate Tata to put the finished touches to the engine.
Tata is the only big firm he'll license to sell the car - and they are limited to India. For the rest of the world he hopes to persuade hundreds of investors to set up their own factories, making the car from 80% locally-sourced materials.
"This will be a major saving in total emissions," he says.
"Imagine we will be able to save all those components travelling the world and all those transporters."
He wants each local factory to sell its own cars to cut out the middle man and he aims for 1% of global sales - about 680,000 per year.
Terry Spall from the Institution of Mechanical Engineers says: "I really hope he succeeds. It is a really brave experiment in producing a sustainable car."
But he said he was interested to see how the car would fare with safety tests and how much it would appeal to a public conditioned to expect luxury fittings adding to the weight of the vehicle.
Mr Negre says there's no issue with safety - if the air-car crashes the air tanks won't shatter - they will split with a very loud bang. "The biggest risk is to the ears."

Apple Brings In the Thinest notebook "MacBook Air"

2008-02-05T04:47:00.000-08:00

MacBook Air is nearly as thin as your index finger. Practically every detail that could be streamlined has been. Yet it still has a 13.3-inch widescreen LED display, full-size keyboard, and large multi-touch trackpad. It’s incomparably portable without the usual ultraportable screen and keyboard compromises.
The incredible thinness of MacBook Air is the result of numerous size- and weight-shaving innovations. From a slimmer hard drive to strategically hidden I/O ports to a lower-profile battery, everything has been considered and reconsidered with thinness in mind.
MacBook Air is designed and engineered to take full advantage of the wireless world. A world in which 802.11n Wi-Fi is now so fast and so available, people are truly living untethered — buying and renting movies online, downloading software, and sharing and storing files on the web.

The brilliance of multi-touch:-
MacBook Air includes an oversize trackpad with multi-touch technology. You can pinch, swipe, or rotate to zoom in on text, advance through a photo album, or adjust an image. This gesture-based input so successful on iPhone and iPod touch now comes to MacBook.

A smart LED display:-
The backlit LED display allows for an even thinner build. It provides instant full-screen brightness the moment you open MacBook Air. The mercury- and arsenic-free display is also more power efficient, which translates to longer battery life.

Thin is in the details:-
The innovative now-you-see-it, now-you-don’t port hatch flips down to reveal (and closes to hide) all the ports you really need: a USB 2.0 port, a headphone jack, and a micro-DVI port that supports DVI, VGA, composite, and S-video output. Even the MagSafe power connection has been reconsidered and slimmed to fit MacBook Air.

So thin yet so expansive:-
MacBook Air comes with a way-more-than-generous 2GB of RAM built in — ample memory for working with your favorite applications. The 80GB hard drive provides plenty of storage space. And you have the option to upgrade to a 64GB solid-state drive, which has no moving parts for enhanced durability.

Micro. Chip:-
MacBook Air performance is as impressive as its form, thanks to its 1.6GHz or 1.8GHz Intel Core 2 Duo processor. This chip was custom-built to fit within the compact dimensions of MacBook Air.

Built-in iSight camera:-
Unlike most other ultraportable notebooks, MacBook Air includes a built-in iSight camera. It’s so smartly integrated, you hardly notice it’s there. The iSight camera and iChat software make video chatting easy anywhere there’s a wireless network.

The battery is slimmer The performance isn’t:-
The MacBook Air battery is our thinnest ever, yet it doesn’t compromise power. You can access the web wirelessly for five full hours.

Hafnium-based Intel® 45nm Process Technology

2008-02-03T02:01:00.000-08:00

Two words: relentless innovation. Using dramatically new materials including hafnium-based circuitry, new Intel® 45nm Hi-k metal gate silicon technology helps to dramatically increase processor energy efficiency and performance for an unprecedented computing experience.With this breakthrough transistor technology, Intel is manufacturing serious advantage into every hafnium-based Intel 45nm Hi-k chip.These revolutionary new processors empower a more enjoyable computing experience for your gaming, multimedia and multitasking, at work, at home, and at play.

Innovation That Breaks the Performance Barrier
Intel® 45nm high-k metal gate silicon technology is the next-generation Intel® Core™ microarchitecture. With roughly twice the density of Intel® 65nm technology, Intel's 45nm packs about double the number of transistors into the same silicon space. That's more than 400 million transistors for dual-core processors and more than 800 million for quad-core. Intel's 45nm technology enables great performance leaps, up to 50-percent larger L2 cache, and new levels of breakthrough energy efficiency.

Smaller transistors pack the performance punch
Intel's had the world's first viable 45nm processors in-house since early January 2007—the first of fifteen 45nm processor products in development. With one of the biggest advancements in fundamental transistor design in 40 years, Intel 45nm high-k silicon technology can deliver more than a 20 percent improvement in transistor switching speed, and reduce transistor gate leakage by over 10 fold.

Taking great leaps forward in transistor design
Using a combination of new materials including hafnium-based high-k gate dielectrics and metal gates, Intel 45nm technology represents a major milestone as the industry as a whole races to reduce electrical current leakage in transistors—a growing problem for chip manufacturers as transistors get even smaller.This new transistor breakthrough allows Intel to continue delivering record-breaking PC, laptop, and server processor speeds well into the future. It also ensures that Moore's Law—a high-tech industry axiom that transistor counts double about every two years to deliver more performance and functionality at decreasing cost—thrives well into the next decade.

Delivering the world's first 45nm processor to the world
The first processors based on the new Intel 45nm high-k silicon technology deliver many new architectural advancements impacting hardware and software performance. Intel has also moved to 100 percent lead-free materials in our 45nm technology and is making the additional move to halogen-free products in 2008 in order to meet our environmental performance goals. Included in the first 45nm launch are new members of the Intel® Core™2 processor and Intel® Xeon® processor families.

Wanna Know about Web Search Engine...???

2008-01-31T04:57:00.000-08:00

A Web search engine is a search engine designed to search for information on the World Wide Web. Information may consist of web pages, images and other types of files.
Some search engines also mine data available in newsgroups, databases, or open directories. Unlike Web directories, which are maintained by human editors, search engines operate algorithmically or are a mixture of algorithmic and human input.

How Web search engines work??
A search engine operates, in the following order

1. Web crawling
2. Indexing
3. Searching

Web search engines work by storing information about a large number of web pages, which they retrieve from the WWW itself. These pages are retrieved by a Web crawler (sometimes also known as a spider) — an automated Web browser which follows every link it sees. Exclusions can be made by the use of robots.txt. The contents of each page are then analyzed to determine how it should be indexed (for example, words are extracted from the titles, headings, or special fields called meta tags). Data about web pages are stored in an index database for use in later queries. Some search engines, such as Google, store all or part of the source page (referred to as a cache) as well as information about the web pages, whereas others, such as AltaVista, store every word of every page they find. This cached page always holds the actual search text since it is the one that was actually indexed, so it can be very useful when the content of the current page has been updated and the search terms are no longer in it. This problem might be considered to be a mild form of linkrot, and Google's handling of it increases usability by satisfying user expectations that the search terms will be on the returned webpage. This satisfies the principle of least astonishment since the user normally expects the search terms to be on the returned pages. Increased search relevance makes these cached pages very useful, even beyond the fact that they may contain data that may no longer be available elsewhere.
When a user enters a query into a search engine (typically by using key words), the engine examines its index and provides a listing of best-matching web pages according to its criteria, usually with a short summary containing the document's title and sometimes parts of the text. Most search engines support the use of the boolean operators AND, OR and NOT to further specify the search query. Some search engines provide an advanced feature called proximity search which allows users to define the distance between keywords.
The usefulness of a search engine depends on the relevance of the result set it gives back. While there may be millions of webpages that include a particular word or phrase, some pages may be more relevant, popular, or authoritative than others. Most search engines employ methods to rank the results to provide the "best" results first. How a search engine decides which pages are the best matches, and what order the results should be shown in, varies widely from one engine to another. The methods also change over time as Internet usage changes and new techniques evolve.
Most Web search engines are commercial ventures supported by advertising revenue and, as a result, some employ the controversial practice of allowing advertisers to pay money to have their listings ranked higher in search results. Those search engines which do not accept money for their search engine results make money by running search related ads alongside the regular search engine results. The search engines make money every time someone clicks on one of these ads.
The vast majority of search engines are run by private companies using proprietary algorithms and closed databases, though some are open source.

Some of the Popular search engines used are:-
1. Google
2. Yahoo! Search
3. Microsoft
4. Baidu

2008-01-28T07:49:00.000-08:00

Bluetooth is an industrial specification for wireless personal area networks (PANs). Bluetooth provides a way to connect and exchange information between devices such as mobile phones, laptops, PCs, printers, digital cameras, and video game consoles over a secure, globally unlicensed short-range radio frequency. The Bluetooth specifications are developed and licensed by the Bluetooth Special Interest Group.

Communication and connection:
A master Bluetooth device can communicate with up to seven devices. This network group of up to eight devices is called a piconet.
A piconet is an ad-hoc computer network, using Bluetooth technology protocols to allow one master device to interconnect with up to seven active devices. Up to 255 further devices can be inactive, or parked, which the master device can bring into active status at any time.
At any given time, data can be transferred between the master and one other device, however, the devices can switch roles and the slave can become the master at any time. The master switches rapidly from one device to another in a round-robin fashion. (Simultaneous transmission from the master to multiple other devices is possible, but not used much.)
Bluetooth specification allows connecting two or more piconets together to form a scatternet, with some devices acting as a bridge by simultaneously playing the master role and the slave role in one piconet. These devices are planned for 2007.
Many USB Bluetooth adapters are available, some of which also include an IrDA adapter. Older (pre-2003) Bluetooth adapters, however, have limited services, offering only the Bluetooth Enumerator and a less-powerful Bluetooth Radio incarnation. Such devices can link computers with Bluetooth, but they do not offer much in the way of services that modern adapters do.

Pairing:-
Pairs of devices may establish a trusted relationship by learning (by user input) a shared secret known as a passkey. A device that wants to communicate only with a trusted device can cryptographically authenticate the identity of the other device. Trusted devices may also encrypt the data that they exchange over the air so that no one can listen in. The encryption can, however, be turned off, and passkeys are stored on the device file system, not on the Bluetooth chip itself. Since the Bluetooth address is permanent, a pairing is preserved, even if the Bluetooth name is changed. Pairs can be deleted at any time by either device. Devices generally require pairing or prompt the owner before they allow a remote device to use any or most of their services. Some devices, such as Sony Ericsson phones, usually accept OBEX business cards and notes without any pairing or prompts.
Certain printers and access points allow any device to use its services by default, much like unsecured Wi-Fi networks. Pairing algorithms are sometimes manufacturer-specific for transmitters and receivers used in applications such as music and entertainment.

Security:-
Bluetooth implements confidentiality, authentication and key derivation with custom algorithms based on the SAFER+ block cipher. In Bluetooth, key generation is generally based on a Bluetooth PIN, which has to be entered into both devices. This procedure might get modified slightly, if one of the devices has a fixed PIN, which is the case e.g. for headsets or similar devices with a restricted user interface. Foremost, an initialization key or master key is generated, using the E22 algorithm .
The E0 stream cipher is used for encrypting packets, granting confidentiality and is based on a shared cryptographic secret, namely a previously generated link key or master key. Those keys, used for subsequent encryption of data sent via the air interface, hardly rely on the Bluetooth PIN, which has been entered into one or both devices.
A demonstration of this reduction has been put effort in by Y. Shaked and A. Wool in . An overview of the most important vulnerabilities and the most common exploits to those vulnerabilities is presented in.

Want to know about Anti Collision Device Used By Indian Railways....??

2008-01-28T07:45:00.000-08:00

Safety violations due to ‘human errors or limitations’ and ‘equipment failures’ occasionally result in Train collisions. Patented by Konkan Railway Corporation, ‘Anti-Collision Device Network’ (also called ‘Raksha KavachTM’, meaning ‘A Train Safety Shield’) is an on-board train collision prevention system.

Designed as a ‘non-signal’ system, it provides ‘non-vital’ ‘safety enhancement’ layer over the existing safety systems of train operations. ‘ACD Network’ therefore fills up ‘safety gaps’ left out due to limitations of existing ‘signal’ based train protection systems.

‘ACD Network’ consists of mobile ACDs (on Locomotives and Guard’s Brake Vans) and trackside ACDs (at Stations, Level Crossings, Locosheds, Sensors based and Repeaters, en-route). Mobile ACDs take inputs from GPS satellite system for position updates and network with track-side ACDs located within a radius of Three Kms (using UHF radio modems); to activate brake(s) with the help of on-board Loco ACD(s) through their Automatic Braking Units (ABUs), whenever a collision-like situation is ‘perceived’. ‘ACD Network’ is likely to prevent ‘head-on’ and ‘rear-end’ collisions in mid-sections, collisions at ‘high speed’ in ‘station area’, ‘side collisions’ with derailed vehicles obstructing adjacent line, collisions due to ‘train parting / jumbling’ and collisions with ‘road vehicles’ at level crossing through ‘Train Approach’ warning and detection of ‘Gate Open’. Loco ACDs also give ‘Station Approach’ warning to drivers. Moreover, using Manual ‘SOS’ buttons on their ACDs, Drivers, Guards and Station Masters can also ‘stop’ trains when any unusual is detected.

Want to know about the technology behind Electronic Paper..?

2008-01-22T20:14:00.001-08:00

Electronic paper, also called e-paper, is a display technology designed to mimic the appearance of ordinary ink on paper. Unlike a conventional flat panel display, which uses a backlight to illuminate its pixels, electronic paper reflects light like ordinary paper and is capable of holding text and images indefinitely without drawing electricity, while allowing the image to be changed later.
There are several different technologies to build e-paper, some of which can use plastic substrate and electronics, so that the display is bendable. Due to the stable image, which does not need to be constantly refreshed, the contrast ratio similar to that of a newspaper, and a very large viewing angle, it is more comfortable to read than a conventional flat display. It is lightweight and durable, but still lacks good colors.
Applications include e-book readers capable of displaying digital versions of books and e-paper magazines, electronic pricing labels in retail shops [1], time tables at bus stations , and electronic billboards.
Electronic paper should not be confused with digital paper, which is a pad to create handwritten digital documents with a digital pen.

Technology:-
Electronic paper was first developed in the 1970s by Nick Sheridon at Xerox's Palo Alto Research Center. The first electronic paper, called Gyricon, consisted of polyethylene spheres between 20 and 100 micrometres across. Each sphere is composed of negatively charged black plastic on one side and positively charged white plastic on the other (each bead is thus a dipole). The spheres are embedded in a transparent silicone sheet, with each sphere suspended in a bubble of oil so that they can rotate freely. The polarity of the voltage applied to each pair of electrodes then determines whether the white or black side is face-up, thus giving the pixel a white or black appearance.

Electrophoretic:An electrophoretic display is an information display that forms visible images by rearranging charged pigment particles using an applied electric field.In the simplest implementation of an electrophoretic display, titanium dioxide particles approximately one micrometre in diameter are dispersed in a hydrocarbon oil. A dark-colored dye is also added to the oil, along with surfactants and charging agents that cause the particles to take on an electric charge. This mixture is placed between two parallel, conductive plates separated by a gap of 10 to 100 micrometres. When a voltage is applied across the two plates, the particles will migrate electrophoretically to the plate bearing the opposite charge from that on the particles. When the particles are located at the front (viewing) side of the display, it appears white, because light is scattered back to the viewer by the high-index titania particles. When the particles are located at the rear side of the display, it appears dark, because the incident light is absorbed by the colored dye. If the rear electrode is divided into a number of small picture elements (pixels), then an image can be formed by applying the appropriate voltage to each region of the display to create a pattern of reflecting and absorbing regions.
Electrophoretic displays are considered prime examples of the electronic paper category, because of their paper-like appearance and low power consumption.
Examples of commercial electrophoretic displays include the high-resolution active matrix displays used in the Amazon Kindle, Sony Librie, Sony Reader, and iRex iLiad e-readers. These displays are constructed from an electrophoretic imaging film manufactured by E Ink Corporation. The Motorola Motofone is the first mobile phone which uses the technology to help eliminate glare from direct sunlight during outdoor use.Another producer of electrophoretic displays is the California based company SiPix. Sipix, along with manufacturing partner SmartDisplayer, received a 1996 Society for Information Display Gold Award for an IC smart card with an integrated electrophoretic display. Electrophoretic displays can be manufactured using the Electronics on Plastic by Laser Release (EPLaR) process developed by Philips Reasarch to enable existing AM-LCD manufacturing plants to create flexible plastic displays.
In the 1990s another type of electronic paper was invented by Joseph Jacobson, who later co-founded the E Ink Corporation which formed a partnership with Philips Components two years later to develop and market the technology. In 2005, Philips sold the electronic paper business as well as its related patents to Prime View International. This used tiny microcapsules filled with electrically charged white particles suspended in a colored oil. In early versions, the underlying circuitry controls whether the white particles were at the top of the capsule (so it looked white to the viewer) or at the bottom of the capsule (so the viewer saw the color of the oil). This was essentially a reintroduction of the well-known electrophoretic display technology, but the use of microcapsules allowed the display to be used on flexible plastic sheets instead of glass.One early version of electronic paper consists of a sheet of very small transparent capsules, each about 40 micrometres across. Each capsule contains an oily solution containing black dye (the electronic ink), with numerous white titanium dioxide particles suspended within. The particles are slightly negatively charged, and each one is naturally white.The microcapsules are held in a layer of liquid polymer, sandwiched between two arrays of electrodes, the upper of which is made from indium tin oxide, a transparent conducting material. The two arrays are aligned so that the sheet is divided into pixels, which each pixel corresponding to a pair of electrodes situated either side of the sheet. The sheet is laminated with transparent plastic for protection, resulting in an overall thickness of 80 micrometres, or twice that of ordinary paper.

The network of electrodes is connected to display circuitry, which turns the electronic ink 'on' and 'off' at specific pixels by applying a voltage to specific pairs of electrodes. Applying a negative charge to the surface electrode repels the particles to the bottom of local capsules, forcing the black dye to the surface and giving the pixel a black appearance. Reversing the voltage has the opposite effect - the particles are forced from the surface, giving the pixel a white appearance. A more recent incarnation of this concept requires only one layer of electrodes beneath the microcapsules.

Bistable LCD:Some companies also produce epaper displays based on bistable LCD technology. The french company Nemoptic commercializes bistable nematic epaper displays (B&W and color) based on a unique principle called “surface anchoring breaking”. The technology used, called BiNem®, has two stable states, the Uniform (U) state and the Twisted (T) state, which are selected by applying simple pulses. Once either state is selected, it stays like it is forever without consuming any additional power. An electrical pulse drives from one state to the other one. This pulse first lifts the molecules on the surface with the weak anchoring layer up to the point where the anchoring is broken. Then, depending on the shape of the falling edge of the pulse, the molecules organize either in U or T state. Bistable LCD diplays offer high reflectivity, resolution up to 200 ppi and a quite neutral white point.

What is Internet2...?

2008-01-22T04:34:00.000-08:00

Internet2 or UCAID (University Corporation for Advanced Internet Development) is a non-profit consortium which develops and deploys advanced network applications and technologies, for education and high-speed data transfer purposes. It is led by 212 universities and partners with 60 companies in areas from the networking (Cisco Systems, Nortel and others), publishing (Prous Science) and technology industries such as Comcast, Intel and Sun Microsystems. "Internet2" is a registered trademark. The consortium is based from administrative headquarters in Ann Arbor, Michigan.
Internet2 (and its members) created the Abilene Network and was a prime investor ($10 million) in the National LambdaRail (NLR) project . During 2004–2006, Internet2 and NLR held extensive discussions regarding a possible merger. Key to this merger was the condition that Internet2 would operate its successor to Abilene using NLR's infrastructure (NLR has IRUs on actual fiber infrastructure from WilTel, now Level(3), where Internet2 utilizes leased optical wavelengths from Qwest for Abilene). Those talks paused in the Spring of 2006, resumed in March of 2007 and eventually fell apart in September of 2007.

These technologies and their organizational counterparts were not only created to make a faster alternative to the internet. More and more applications for Internet2 technology become apparent all the time. Many fields have been able to use the Abilene network to foster creativity, research, and development in a way that was not previously possible. Users of poor quality libraries can now download not only text but sound recordings, animations, videos, and other resources, which would be otherwise unavailable. Another application is the robust video conferencing now available to Internet2 participants. Neurosurgeons can now video conference with other experts in the field during an operation in a high resolution format with no apparent time lag. There are many other possible applications for this network.

The beginnings of the internet were based on the communications of computers over a network. One of the first major examples of such a network was ARPAnet, developed by the Defense Advanced Research Projects Agency. Another was the University of Illinois PLATO educational network. As more networks like ARPAnet were created, the need to standardize and make them compatible arose. This is how the Internet began to evolve into what it is today.

Governments and universities are among the first institutions to outgrow the internet's bandwidth limitations. Some universities realized the need for a network that would better support bandwidth- and computer-intensive work, like data mining, medical imaging, and particle physics. This need for a higher bandwidth network resulted in the creation of the very-high-performance Backbone Network Service, or vBNS. The vBNS was developed in 1995 by the National Science Foundation and MCI telecommunications company specifically to meet the needs of the supercomputers at educational institutions. The concept of “the next generation of internet” was born. MCI engineered this backbone for the National Science Foundation, but when their agreement expired the participating institutions looked to the Internet2 organization to offer the same service as MCI.

How does food gets cooked in Microwave Ovens...???

2008-01-14T05:56:00.000-08:00

A microwave oven, or microwave, is a kitchen appliance employing microwave radiation primarily to cook or heat food. Microwave ovens have revolutionized food preparation since their use became widespread in the 1970s.A microwave oven consists of:
* a high voltage transformer, which passes energy to the magnetron
* a cavity magnetron,
* a magnetron control circuit (usually with a microcontroller),
* a waveguide, and
* a cooking chamber

A microwave oven works by passing non-ionizing microwave radiation, usually at a frequency of 2.45 GHz (a wavelength of 12.24 cm), through the food. Microwave radiation is between common radio and infrared frequencies. Water, fat, and other substances in the food absorb energy from the microwaves in a process called dielectric heating. Many molecules (such as those of water) are electric dipoles, meaning that they have a positive charge at one end and a negative charge at the other, and therefore rotate as they try to align themselves with the alternating electric field of the microwaves. This molecular movement creates heat as the rotating molecules hit other molecules and put them into motion. Microwave heating is most efficient on liquid water, and much less so on fats and sugars (which have less molecular dipole moment), and frozen water (where the molecules are not free to rotate). Microwave heating is sometimes explained as a rotational resonance of water molecules, but this is incorrect: such resonance only occurs in water vapor at much higher frequencies, at about 20 gigahertz. Moreover, large industrial/commercial microwave ovens operating at the common large industrial-oven microwave heating frequency of 915 MHz (0.915 GHz), also heat water and food perfectly well. [1] The frequencies used in microwave ovens were chosen based on two constraints. The first is that that they should be in one of the ISM bands set aside for non-communication purposes. Three additional ISM bands exist in the microwave frequencies, but are not used for microwave cooking. Two of them are centered on 5.8 GHz and 24.125 GHz, but are not used for microwave cooking because of the very high cost of power generation at these frequencies. The third, centered on 433.92 MHz, is a narrow band that would require expensive equipment to generate sufficient power without creating interference outside the band, and is only available in some countries. For household puposes, 2.45 GHz has the advantage over 915 MHz in that 915 MHz is not an ISM band in all countries while 2.45GHz is available worldwide.A common misconception is that microwave ovens cook food from the "inside out". In reality, microwaves are absorbed in the outer layers of food in a manner somewhat similar to heat from other methods. The misconception arises because microwaves penetrate dry non-conductive substances at the surfaces of many common foods, and thus often deposit initial heat more deeply than other methods. Depending on water content, the depth of initial heat deposition may be several centimeters or more with microwave ovens, in contrast to broiling (infrared) or convection heating, which deposit heat thinly at the food surface. Depth of penetration of microwaves is dependent on food composition and the frequency, with lower microwave frequencies penetrating better.Most microwave ovens allow the user to choose between several power levels, including one or more defrosting levels. In most ovens, however, there is no change in the intensity of the microwave radiation; instead, the magnetron is turned on and off in cycles of several seconds at a time. This can actually be observed when microwaving airy foods which may inflate during heating phases, and deflate when the magnetron is turned off. For such ovens, the magnetron is driven by a linear transformer which can only feasibly be switched completely on or off. Newer models have inverter power supplies which use Pulse width modulation to provide truly continuous low-power microwave heating.The cooking chamber itself is a Faraday cage enclosure which prevents the microwaves from escaping into the environment. The oven door is usually a glass panel for easy viewing, but has a layer of conductive mesh to maintain the shielding. Because the size of the perforations in the mesh is much less than the wavelength of 12 cm, most of the microwave radiation cannot pass through the door, while visible light (with a much shorter wavelength) can. With wireless computer networks gaining in popularity, microwave interference has become a concern near wireless networks. Microwave ovens are capable of disrupting wireless network transmissions because the ovens generate radio waves of about 2.45 GHz in the 802.11b/g frequency band, some of them escaping the enclosure despite the presence of the mesh.Microwave ovens are generally used for time efficiency in both industrial applications such as restaurants and at home, rather than for cooking quality, although some modern recipes using microwave ovens rival recipes using traditional ovens and stoves. Professional chefs generally find microwave ovens to be of limited usefulness because the Maillard reactions cannot occur due to the temperature range.[1]. On the other hand, people who want fast cooking times can use microwave ovens to prepare food or to reheat stored food (including commercially available pre-cooked frozen dishes) in only a few minutes. Popcorn is one example of a very popular item with microwave oven users.A variant of the conventional microwave is the convection microwave. A convection microwave is a combination of a standard microwave and a convection oven. It allows food to be cooked quickly, yet come out browned or crisped, as from a convection oven. Convection microwaves are more expensive than a conventional microwave. They are not considered cost-effective if primarily used just to heat drinks or frozen food. They are usually used for cooking a prepared dish.More recently, certain manufacturers have added a high power quartz halogen bulb to their convection microwave models while marketing them under names such as "Speedcook", "Advantium" and "Optimawave" to emphasize their ability to cook food rapidly and with the same browning results typically expected of a conventional oven. This is achieved using the high intensity halogen lights at the top of the microwave to deposit large amounts of infrared radiation to the surface of the food. The food browns while also being heated internally by the microwave radiation and heated through conduction and convection by contact with heated air - produced by the conventional convection portion of the unit. The IR energy which is rapidly delivered to the outer surface of food by the lamps is sufficient to initiate browning and caramelization reactions in a particular food's proteins and carbohydrates, producing a texture and taste much more similar to that typically expected of conventional oven cooking rather than the bland boiled and steamed taste that microwave-only cooking tends to create.In order to aid browning, sometimes an accessory browning tray is used.

How LED glows....???

2008-01-13T07:13:00.000-08:00

A light-emitting diode (LED) is a semiconductor diode that emits incoherent narrow-spectrum light when electrically biased in the forward direction of the p-n junction, as in the common LED circuit. This effect is a form of electroluminescence.
An LED is usually a small area source, often with extra optics added to the chip that shapes its radiation pattern.[2] LED's are often used as small indicator lights on electronic devices and increasingly in higher power applications such as flashlights and area lighting. The color of the emitted light depends on the composition and condition of the semiconducting material used, and can be infrared, visible, or near-ultraviolet. An LED can be used as a regular household light source.

Physical Functions:
Like a normal diode, an LED consists of a chip of semiconducting material impregnated, or doped, with impurities to create a p-n junction. As in other diodes, current flows easily from the p-side, or anode, to the n-side, or cathode, but not in the reverse direction. Charge-carriers—electrons and holes—flow into the junction from electrodes with different voltages. When an electron meets a hole, it falls into a lower energy level, and releases energy in the form of a photon.
The wavelength of the light emitted, and therefore its color, depends on the band gap energy of the materials forming the p-n junction. In silicon or germanium diodes, the electrons and holes recombine by a non-radiative transition which produces no optical emission, because these are indirect band gap materials. The materials used for an LED have a direct band gap with energies corresponding to near-infrared, visible or near-ultraviolet light.
LED development began with infrared and red devices made with gallium arsenide. Advances in materials science have made possible the production of devices with ever-shorter wavelengths, producing light in a variety of colors.
LEDs are usually built on an n-type substrate, with an electrode attached to the p-type layer deposited on its surface. P-type substrates, while less common, occur as well. Many commercial LEDs, especially GaN/InGaN, also use sapphire substrate. Substrates that are transparent to the emitted wavelength, and backed by a reflective layer, increase the LED efficiency. The refractive index of the package material should match the index of the semiconductor, otherwise the produced light gets partially reflected back into the semiconductor, where it may be absorbed and turned into additional heat, thus lowering the efficiency. This type of reflection also occurs at the surface of the package if the LED is coupled to a medium with a different refractive index such as a glass fiber or air. The refractive index of most LED semiconductors is quite high, so in almost all cases the LED is coupled into a much lower-index medium. The large index difference makes the reflection quite substantial (per the Fresnel coefficients), and this is usually one of the dominant causes of LED inefficiency. Often more than half of the emitted light is reflected back at the LED-package and package-air interfaces. The reflection is most commonly reduced by using a dome-shaped (half-sphere) package with the diode in the center so that the outgoing light rays strike the surface perpendicularly, at which angle the reflection is minimized. An anti-reflection coating may be added as well. The package may be cheap plastic, which may be colored, but this is only for cosmetic reasons or to improve the contrast ratio; the color of the packaging does not substantially affect the color of the light emitted. Other strategies for reducing the impact of the interface reflections include designing the LED to reabsorb and reemit the reflected light (called photon recycling) and manipulating the microscopic structure of the surface to reduce the reflectance, either by introducing random roughness or by creating programmed moth eye surface patterns.

Conventional LEDs are made from a variety of inorganic semiconductor materials, producing the following colors:

* Aluminium gallium arsenide (AlGaAs) — red and infrared
* Aluminium gallium phosphide (AlGaP) — green
* Aluminium gallium indium phosphide (AlGaInP) — high-brightness orange-red, orange, yellow, and green
* Gallium arsenide phosphide (GaAsP) — red, orange-red, orange, and yellow
* Gallium phosphide (GaP) — red, yellow and green
* Gallium nitride (GaN) — green, pure green (or emerald green), and blue also white (if it has an AlGaN Quantum Barrier)
* Indium gallium nitride (InGaN) — 450nm - 470nm — near ultraviolet, bluish-green and blue
* Silicon carbide (SiC) as substrate — blue
* Silicon (Si) as substrate — blue (under development)
* Sapphire (Al2O3) as substrate — blue
* Zinc selenide (ZnSe) — blue
* Diamond (C) — ultraviolet
* Aluminium nitride (AlN), aluminium gallium nitride (AlGaN), aluminium gallium indium nitride (AlGaInN) — near to far ultraviolet (down to 210 nm)

With this wide variety of colors, arrays of multicolor LEDs can be designed to produce unconventional color patterns.

Finally The Worlds Cheapest Car Is Out......

2008-01-12T04:17:00.000-08:00

Mr. Ratan N. Tata, Chairman of the Tata Group and Tata Motors, today unveiled the Tata ‘NANO’, the People’s Car from Tata Motors that India and the world have been looking forward to.
A development, which signifies a first for the global automobile industry, the People’s Car brings the comfort and safety of a car within the reach of thousands of families. The People’s Car will be launched in India later in 2008.Speaking at the unveiling ceremony at the 9th Auto Expo in New Delhi, Mr. Ratan N. Tata said, “I observed families riding on two-wheelers – the father driving the scooter, his young kid standing in front of him, his wife seated behind him holding a little baby. It led me to wonder whether one could conceive of a safe, affordable, all-weather form of transport for such a family. Tata Motors’ engineers and designers gave their all for about four years to realise this goal. Today, we indeed have a People’s Car, which is affordable and yet built to meet safety requirements and emission norms, to be fuel efficient and low on emissions. We are happy to present the People’s Car to India and we hope it brings the joy, pride and utility of owning a car to many families who need personal mobility.”

Stylish, comfortable
The People’s Car, designed with a family in mind, has a roomy passenger compartment with generous leg space and head room. It can comfortably seat four persons. Four doors with high seating position make ingress and egress easy.Yet with a length of 3.1 metres, width of 1.5 metres and height of 1.6 metres, with adequate ground clearance, it can effortlessly manoeuvre on busy roads in cities as well as in rural areas. Its mono-volume design, with wheels at the corners and the powertrain at the rear, enables it to uniquely combine both space and manoeuvrability, which will set a new benchmark among small cars.When launched, the car will be available in both standard and deluxe versions. Both versions will offer a wide range of body colours, and other accessories so that the car can be customised to an individual’s preferences.

Fuel-efficient engine
The People’s Car has a rear-wheel drive, all-aluminium, two-cylinder, 623 cc, 33 PS, multi point fuel injection petrol engine. This is the first time that a two-cylinder gasoline engine is being used in a car with single balancer shaft. The lean design strategy has helped minimise weight, which helps maximise performance per unit of energy consumed and delivers high fuel efficiency. Performance is controlled by a specially designed electronic engine management system.

Meets all safety requirements
The People’s Car’s safety performance exceeds current regulatory requirements. With an all sheet-metal body, it has a strong passenger compartment, with safety features such as crumple zones, intrusion-resistant doors, seat belts, strong seats and anchorages, and the rear tailgate glass bonded to the body. Tubeless tyres further enhance safety.

Environment-friendly
The People’s Car’s tailpipe emission performance exceeds regulatory requirements. In terms of overall pollutants, it has a lower pollution level than two-wheelers being manufactured in India today. The high fuel efficiency also ensures that the car has low carbon dioxide emissions, thereby providing the twin benefits of an affordable transportation solution with a low carbon footprint.

So Want to Know about Flying Train...?

2008-01-09T06:16:00.000-08:00

A maglev, or magnetically levitating train, is a form of transportation that suspends, guides and propels vehicles (predominantly trains) using electromagnetic force. This method has the potential to be fast and quiet when compared to wheeled mass transit systems, potentially reaching velocities comparable to turboprop and jet aircraft (900 km/h, 600 mph). The highest recorded speed of a maglev train is 581 km/h (361 mph), achieved in Japan in 2003, 6 km/h higher than the conventional TGV speed record.

Technology:-
All operational implementations of maglev technology have had minimal overlap with wheeled train technology and have not been compatible with conventional rail tracks. Because they cannot share existing infrastructure, maglevs must be designed as complete transportation systems. The term "maglev" refers not only to the vehicles, but to the railway system as well, specifically designed for magnetic levitation and propulsion.There are two primary types of maglev technology:

* electromagnetic suspension (EMS) uses the attractive magnetic force of a magnet beneath a rail to lift the train up.
* electrodynamic suspension (EDS) uses a repulsive force between two magnetic fields to push the train away from the rail.
Another experimental technology, which was designed, proven mathematically, peer reviewed, and patented, but is yet to be built, is the magnetodynamic suspension (MDS), which uses the attractive magnetic force of a permanent magnet array near a steel track to lift the train and hold it in place.

Electromagnetic suspension:
In current EMS systems, the train levitates above a steel rail while electromagnets, attached to the train, are oriented toward the rail from below. The electromagnets use feedback control to maintain a train at a constant distance from the track, at approximately 15 millimeters (0.6 in)
Electrodynamic suspension:

In Electrodynamic suspension (EDS), both the rail and the train exert a magnetic field, and the train is levitated by the repulsive force between these magnetic fields. The magnetic field in the train is produced by either electromagnets (as in JR-Maglev) or by an array of permanent magnets (as in Inductrack). The repulsive force in the track is created by an induced magnetic field in wires or other conducting strips in the track.
At slow speeds, the current induced in these coils and the resultant magnetic flux is not large enough to support the weight of the train. For this reason the train must have wheels or some other form of landing gear to support the train until it reaches a speed that can sustain levitation.
Propulsion coils on the guideway are used to exert a force on the magnets in the train and make the train move forward. The propulsion coils that exert a force on the train are effectively a linear motor: An alternating current flowing through the coils generates a continuously varying magnetic field that moves forward along the track. The frequency of the alternating current is synchronized to match the speed of the train. The offset between the field exerted by magnets on the train and the applied field create a force moving the train forward.

Magnetodynamic suspension:
Magnetodynamic suspension, invented by Dr. Oleg Tozoni, is similar to the EMS system in that it uses attractive forces, but differs in that the magnets used for suspension are permanent, and the stability is built into the system itself using physics/mechanical systems, as opposed to EMS's computer systems. MDS is based on the idea of using a minimum energy point to balance the train. A simple way to explain this is to compare EMS to a hill, with minimum energy points on the sides of it, and MDS to a valley with the minimum point in the center. The center of each would be the vehicle's suspended center point. If you put a ball on the top of the hill and apply any force to it, the ball will try to roll down, and you would need to apply a compensation force in the other direction to keep it centered. Once the ball gets to the top of the hill, it will try to keep rolling down the other side, and an opposite, compensating force is needed. This is what EMS does when it uses stabilising systems to increase or decrease the strength of the electromagnets holding the train suspended, and that system is inherently unstable, requiring a constant outside stabilising force. MDS, on the other hand, is more like a valley with the energy minimum in the center. It takes energy to move the ball away from the bottom, and the ball returns to the bottom on its own. This is possible because steel magnetic permeability is highly dependent on magnetic flux intensity in that steel. Basically, the more you magnetize steel, the more difficult it is to magnetize it even more. Once the steel becomes fully saturated, bringing a magnet closer to it will not increase the strength of the magnetic field between the magnet and the magnetically saturated steel. Dr. Tozoni figured out how to create what is essentially magnetic insulation, which would keep magnetic fields escaping from the steel rails into the surrounding air, thus concentrating the magnetic field in those rails and saturating them. MDS uses a series of magnets constructed in such a way that when the array is suspended within the steel rail, the lateral, side-to-side, forces pulling the train towards the steel rails become much weaker than the horizontal, up-down, force holding the magnets centered between the rails. When two such magnet arrays are arranged perpendicular to each other, the stronger forces cancel out the weaker forces, forcing the train to stay centered between the rails automatically, thus holding it in the minimum energy point; any outside force that moves the train away from the center line of travel is countered by a force wanting to bring the train back to the center minimum

What is Intranet....?

2008-01-08T04:45:00.000-08:00

An 'intranet' is a private computer network that uses Internet protocols and network connectivity to securely share part of an organization's information or operations with its employees. Sometimes the term refers only to the most visible service, the internal website. The same concepts and technologies of the Internet such as clients and servers running on the Internet protocol suite are used to build an intranet. HTTP and other Internet protocols are commonly used as well, such as FTP. There is often an attempt to use Internet technologies to provide new interfaces with corporate "legacy" data and information systems.
Briefly, an intranet can be understood as "a private version of an Internet," or as a version of the Internet confined to an organization. The term first appeared in print on April 19, 1995, in Digital News & Review in an article authored by technical editor Stephen Lawton

About Intranets:
Intranets differ from "Extranets" in that the former are generally restricted to employees of the organization while extranets can generally be accessed by customers, suppliers, or other approved parties.
There does not necessarily have to be any access from the organization's internal network to the Internet itself. When such access is provided it is usually through a gateway with a firewall, along with user authentication, encryption of messages, and often makes use of virtual private networks (VPNs). Through such devices and systems off-site employees can access company information, computing resources and internal communications.
Increasingly, intranets are being used to deliver tools and applications, e.g., collaboration (to facilitate working in groups and teleconferencing) or sophisticated corporate directories, sales and CRM tools, project management etc., to advance productivity.
Intranets are also being used as culture change platforms. For example, large numbers of employees discussing key issues in an online forum could lead to new ideas.
Intranet traffic, like public-facing web site traffic, is better understood by using web metrics software to track overall activity, as well as through surveys of users.
Intranet "User Experience", "Editorial", and "Technology" teams work together to produce in-house sites. Most commonly, intranets are owned by the communications, HR or CIO areas of large organizations, or some combination of the three.
Because of the scope and variety of content and the number of system interfaces, the intranets of many organisations are much more complex than their respective public websites. And intranets are growing rapidly. According to the Intranet design annual 2007 from Nielsen Norman Group the number of pages on participants' intranets averaged 200,000 over the years 2001 to 2003 and has grown to an average of 6 million pages over 2005–2007.

Advantages of intranets:
1. Workforce productivity: Intranets can help users to locate and view information faster and use applications relevant to their roles and responsibilities. With the help of a web browser interface, users can access data held in any database the organization wants to make available, anytime and - subject to security provisions - from anywhere within the company workstations, increasing employees' ability to perform their jobs faster, more accurately, and with confidence that they have the right information. It also helps to improve the services provided to the users.
2. Time: With intranets, organizations can make more information available to employees on a "pull" basis (ie: employees can link to relevant information at a time which suits them) rather than being deluged indiscriminately by emails.
3. Communication: Intranets can serve as powerful tools for communication within an organization, vertically and horizontally. From a communications standpoint, intranets are useful to communicate strategic initiatives that have a global reach throughout the organization. The type of information that can easily be conveyed is the purpose of the initiative and what the initiative is aiming to achieve, who is driving the initiative, results achieved to date, and who to speak to for more information. By providing this information on the intranet, staff have the opportunity to keep up-to-date with the strategic focus of the organization.
4. Web publishing allows 'cumbersome' corporate knowledge to be maintained and easily accessed throughout the company using hypermedia and Web technologies. Examples include: employee manuals, benefits documents, company policies, business standards, newsfeeds, and even training, can be accessed using common Internet standards (Acrobat files, Flash files, CGI applications). Because each business unit can update the online copy of a document, the most recent version is always available to employees using the intranet.
5. Business operations and management: Intranets are also being used as a platform for developing and deploying applications to support business operations and decisions across the internetworked enterprise.
6. Cost-effective: Users can view information and data via web-browser rather than maintaining physical documents such as procedure manuals, internal phone list and requisition forms.
7. Promote common corporate culture: Every user is viewing the same information within the Intranet.
8. Enhance Collaboration: With information easily accessible by all authorised users, teamwork is enabled.

Planning and creating an intranet:
Most organizations devote considerable resources into the planning and implementation of their intranet as it is of strategic importance to the organization's success. Some of the planning would include topics such as:

* What they hope to achieve from the intranet
* Which person or department would "own" (take control of) the technology and the implementation
* How and when existing systems would be phased out/replaced
* How they intend to make the intranet secure
* How they'll ensure to keep it within legislative and other constraints
* Level of interactivity (eg wikis, on-line forms) desired.
* Is the input of new data and updating of existing data to be centrally controlled or devolved.
These are in addition to the hardware and software decisions (like Content Management Systems), participation issues (like good taste, harassment, confidentiality), and features to be supported.

The actual implementation would include steps such as

1. User involvement to identify users' information needs.
2. Setting up a web server with the correct hardware and software.
3. Setting up web server access using a TCP/IP network.
4. Installing the user programs on all required computers.
5. Creating a homepage for the content to be hosted.
6. User involvement in testing and promoting use of intranet.

What is RADAR Technology...?

2008-01-07T04:42:00.000-08:00

Radar is a system that uses electromagnetic waves to identify the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, ships, motor vehicles, weather formations, and terrain. A transmitter emits radio waves, which are reflected by the target and detected by a receiver, typically in the same location as the transmitter. Although the radio signal returned is usually very weak, radio signals can easily be amplified. This enables a radar to detect objects at ranges where other emissions, such as sound or visible light, would be too weak to detect. Radar is used in many contexts, including meteorological detection of precipitation, measuring ocean surface waves, air traffic control, police detection of speeding traffic, and by the military. It was originally called RDF (Radio Direction Finder) in Britain. The term RADAR was coined in 1941 as an acronym for Radio Detection and Ranging. The term has since entered the English language as a standard word, radar, losing the capitalization in the process.

Principles:-
Reflection:
Electromagnetic waves reflect (scatter) from any large change in the dielectric or diamagnetic constants. This means that a solid object in air or a vacuum, or other significant change in atomic density between the object and what's surrounding it, will usually scatter radar (radio) waves. This is particularly true for electrically conductive materials, such as metal and carbon fiber, making radar particularly well suited to the detection of aircraft and ships. Radar absorbing material, containing resistive and sometimes magnetic substances, is used on military vehicles to reduce radar reflection. This is the radio equivalent of painting something a dark color.
Radar waves scatter in a variety of ways depending on the size (wavelength) of the radio wave and the shape of the target. If the wavelength is much shorter than the target's size, the wave will bounce off in a way similar to the way light is reflected by a mirror. If the wavelength is much longer than the size of the target, the target is polarized (positive and negative charges are separated), like a dipole antenna. This is described by Rayleigh scattering, an effect that creates the Earth's blue sky and red sunsets. When the two length scales are comparable, there may be resonances. Early radars used very long wavelengths that were larger than the targets and received a vague signal, whereas some modern systems use shorter wavelengths (a few centimetres or shorter) that can image objects as small as a loaf of bread.Short radio waves reflect from curves and corners, in a way similar to glint from a rounded piece of glass. The most reflective targets for short wavelengths have 90° angles between the reflective surfaces. A structure consisting of three flat surfaces meeting at a single corner, like the corner on a box, will always reflect waves entering its opening directly back at the source. These so-called corner reflectors are commonly used as radar reflectors to make otherwise difficult-to-detect objects easier to detect, and are often found on boats in order to improve their detection in a rescue situation and to reduce collisions. For similar reasons, objects attempting to avoid detection will angle their surfaces in a way to eliminate inside corners and avoid surfaces and edges perpendicular to likely detection directions, which leads to "odd" looking stealth aircraft. These precautions do not completely eliminate reflection because of diffraction, especially at longer wavelengths. Half wavelength long wires or strips of conducting material, such as chaff, are very reflective but do not direct the scattered energy back toward the source. The extent to which an object reflects or scatters radio waves is called its radar cross section.
Polarization:
n the transmitted radar signal, the electric field is perpendicular to the direction of propagation, and this direction of the electric field is the polarization of the wave. Radars use horizontal, vertical, linear and circular polarization to detect different types of reflections. For example, circular polarization is used to minimize the interference caused by rain. Linear polarization returns usually indicate metal surfaces. Random polarization returns usually indicate a fractal surface, such as rocks or soil, and are used by navigation radars.
Interference:
Radar systems must overcome several different sources of unwanted signals in order to focus only on the actual targets of interest. These unwanted signals may originate from internal and external sources, both passive and active. The ability of the radar system to overcome these unwanted signals defines its signal-to-noise ratio (SNR): the higher a system's SNR, the better it is in isolating actual targets from the surrounding noise signals.
Noise:
Signal noise is an internal source of random variations in the signal, which is inherently generated to some degree by all electronic components. Noise typically appears as random variations superimposed on the desired echo signal received in the radar receiver. The lower the power of the desired signal, the more difficult it is to discern it from the noise (similar to trying to hear a whisper while standing near a busy road). Therefore, the most important noise sources appear in the receiver and much effort is made to minimize these factors. Noise figure is a measure of the noise produced by a receiver compared to an ideal receiver, and this needs to be minimized.Noise is also generated by external sources, most importantly the natural thermal radiation of the background scene surrounding the target of interest. In modern radar systems, due to the high performance of their receivers, the internal noise is typically about equal to or lower than the external scene noise. An exception is if the radar is aimed upwards at clear sky, where the scene is so cold that it generates very little thermal noise.There will be also Flicker noise due to electrons transit, but depending on 1/f, will be much lower than thermal noise when the frequency is high. Hence, in pulse radar, the system will be always heterodyne. See intermediate frequency.

Wanna Know About The Next Generation Hard Disks...?

2007-12-27T05:56:00.001-08:00

A solid state drive (SSD) is a data storage device that uses solid-state memory to store persistent data. An SSD emulates a conventional hard disk drive, thus easily replacing it in any application.
The actual definition of solid-state refers to the use of semiconductor devices rather than electron tubes, but has been adopted for the use of this more modern technology.[citation needed] With no moving parts, a solid state drive largely eliminates seek time, latency and other electro-mechanical delays and failures associated with a conventional hard disk drive.
An SSD is commonly composed of either NAND flash (non-volatile) or SDRAM (volatile).
SSDs based on volatile memory such as SDRAM are categorized by fast data access, less than 0.01 milliseconds (over 250 times faster than the fastest hard drives in 2004) and are used primarily to accelerate applications that would otherwise be held back by the latency of disk drives.
DRAM-based SSDs typically incorporate internal battery and backup disk systems to ensure data persistence. If power is lost for whatever reason, the battery would keep the unit powered long enough to copy all data from random access memory (RAM) to backup disk. Upon the restoration of power, data is copied back from backup disk to RAM and the SSD resumes normal operation.
However, most SSD manufacturers use nonvolatile flash memory to create more rugged and compact alternatives to DRAM-based SSDs. These flash memory-based SSDs, also known as flash drives, do not require batteries, allowing makers to replicate standard disk drive form factors (1.8-inch, 2.5-inch, and 3.5-inch). In addition, nonvolatility allows flash SSDs to retain memory even during sudden power outages, ensuring data retrievability. Just like DRAM SSDs, flash SSDs are extremely fast since these devices have no moving parts, eliminating seek time, latency and other electro-mechanical delays inherent in conventional disk drives. (Though flash SSDs are significantly slower than DRAM SSDs).
Solid state drives are especially useful on a computer that has already come with maximum amount of RAM. For example, some x86 architectures with a 4 GB limit, can effectively be extended by putting the paging file or swap file on an SSD. These SSDs do not provide as fast storage as main RAM because of the bandwidth bottleneck of the bus they connect to, but would still provide a performance increase over placing the swap file on a traditional hard disk drive.
DRAM based SSDs may also work like a buffer cache mechanism. Whenever data is written to memory, the corresponding block in memory is marked as dirty and all dirty blocks can be flushed to the actual hard drive based on the following two strategies:

1. Time (e.g. every 10 seconds, flush all dirty data),
2. Threshold (when the ratio of dirty data to SSD size exceeds some predetermined value, flush the dirty data).

Compared with hard disk drives (HDDs):-
* Faster startup (as no spin-up is required).
* Faster random I/O (compared to hard disk drives).
* Extremely low read and write latency (seek) times, roughly 5 orders of magnitude faster than the best current hard disks drives.[citation needed]
* Faster boot and application launch time when hard disk seeks are the limiting factor. See Amdahl's law.
* In some cases, somewhat longer lifetime[citation needed] – Flash storage typically has a data lifetime on the order of 10 years before degradation. If data is periodically refreshed, it can store data indefinitely.[citation needed]
* Few to no moving parts.
o For small SSDs, lower power consumption and heat production.
o For small SSDs, no noise – Lack of moving parts makes the SSD completely silent (although high-end SSDs may include cooling fans).
o Better mechanical reliability – Lack of moving parts almost eliminates the risk of mechanical failure. High level of ability to endure extreme shock, high altitude, vibration and temperatures,[citation needed] which apply to laptops and other mobile devices, or when transported.
* Relatively deterministic performance – unlike hard disk drives, performance of SSDs is almost constant and deterministic across the entire storage. This is because "Seek time" can be constant, so fragmentation has less impact on performance than on physical drives.
* For very low-capacity SSDs, lower weight and size. Size and weight per unit storage are still better for traditional hard drives, and microdrives allow up to 20 GB storage in a CompactFlash 42.8×36.4×5 mm (1.7×1.4×.2 in) form factor.

Disadvantages:-
Flash based SSDs also have several disadvantages:

* Price – As of late 2007, flash memory prices are still considerably higher per gigabyte than those of comparable conventional hard drives – around US$8 per GB compared to about US$0.25 for mechanical drives.[citation needed]
* Vulnerability to certain types of effects, including abrupt power loss (especially DRAM based SSDs), magnetic fields and electric/static charges compared to normal HDDs (which store the data inside a Faraday cage).
* Limited write cycles. Typical Flash storage will typically wear out after 100,000-300,000 write cycles, while high endurance Flash storage is often marketed with endurance of 1–5 million write cycles (many log files, file allocation tables, and other commonly used parts of the file system exceed this over the lifetime of a computer). Special file systems or firmware designs can mitigate this problem by spreading writes over the entire device, rather than rewriting files in place.
* Slow random write speeds – as erase blocks on SSDs generally are quite large, they're far slower than conventional disks for random writes.
* In some cases, SSDs have substantially lower throughput than conventional hard disks. In spite of the decreased latency, this can lead to dramatically lower performance than hard disk drives. More expensive SSDs can have much greater bandwidth than HDDs, so this isn't universally a problem.

Wanna Know about the technology Behind Global Positioning System(GPS)...?

2007-12-27T05:23:00.000-08:00

The Global Positioning System (GPS) is the only fully functional Global Navigation Satellite System (GNSS). Utilizing a constellation of at least 24 Medium Earth Orbit satellites that transmit precise microwave signals, the system enables a GPS receiver to determine its location, speed, direction, and time. Other similar systems are the Russian GLONASS (incomplete as of 2007) and the upcoming European Galileo positioning system.
Developed by the United States Department of Defense, GPS is officially named NAVSTAR GPS (Contrary to popular belief, NAVSTAR is not an acronym, but simply a name given by Mr. John Walsh, a key decision maker when it came to the budget for the GPS program). The satellite constellation is managed by the United States Air Force 50th Space Wing. The cost of maintaining the system is approximately US$750 million per year, including the replacement of aging satellites, and research and development.
Following the shootdown of Korean Air Lines Flight 007 in 1983, President Ronald Reagan issued a directive making the system available for free for civilian use as a common good. Since then, GPS has become a widely used aid to navigation worldwide, and a useful tool for map-making, land surveying, commerce, and scientific uses. GPS also provides a precise time reference used in many applications including scientific study of earthquakes, and synchronization of telecommunications networks.

Simplified method of operation:-
A typical GPS receiver calculates its position using the signals from four or more GPS satellites. Four satellites are needed since the process needs a very accurate local time, more accurate than any normal clock can provide, so the receiver internally solves for time as well as position. In other words, the receiver uses four measurements to solve for 4 variables - x, y, z, and t. These values are then turned into more user-friendly forms, such as latitude/longitude or location on a map, then displayed to the user.
Each GPS satellite has an atomic clock, and continually transmits messages containing the current time at the start of the message, parameters to calculate the location of the satellite (the ephemeris), and the general system health (the almanac). The signals travel at a known speed - the speed of light through outer space, and slightly slower through the atmosphere. The receiver uses the arrival time to compute the distance to each satellite, from which it determines the position of the receiver using geometry and trigonometry. If the local time is known very precisely, this process (known as trilateration[4]) can determine the receiver's position using three satellites. However, most receivers do not contain clocks of this accuracy (an atomic clock would be required), and so require tracking four or more satellites so that the receiver can compute both the accurate time and its location.

What happens inside our vehicle engine...?

2007-12-22T06:19:00.000-08:00

The type of engine present inside our vehicles is know as internal combustion engine. The internal combustion engine is an engine in which the combustion of fuel and an oxidizer (typically air) occurs in a confined space called a combustion chamber. This exothermic reaction creates gases at high temperature and pressure, which are permitted to expand. The defining feature of an internal combustion engine is that useful work is performed by the expanding hot gases acting directly to cause movement of solid parts of the engine, by acting on pistons, rotors, or even by pressing on and moving the entire engine itself.
This contrasts with external combustion engines, such as steam engines and Stirling engines, which use an external combustion chamber to heat a separate working fluid, which then in turn does work, for example by moving a piston or a turbine.
The term Internal Combustion Engine (ICE) is almost always used to refer specifically to reciprocating piston engines, Wankel engines and similar designs in which combustion is intermittent. However, continuous combustion engines, such as jet engines, most rockets and many gas turbines are also internal combustion engines.

All internal combustion engines depend on the exothermic chemical process of combustion: the reaction of a fuel, typically with the oxygen from the air, although other oxidizers such as nitrous oxide may be employed. Also see stoichiometry.
The most common modern fuels are made up of hydrocarbons and are derived mostly from petroleum. These include the fuels known as dieselfuel, gasoline and petroleum gas, and the rarer use of propane gas. Most internal combustion engines designed for gasoline can run on natural gas or liquefied petroleum gases without major modifications except for the fuel delivery components. Liquid and gaseous biofuels, such as ethanol and biodiesel (a form of diesel fuel that is produced from crops that yield triglycerides such as soybean oil) can also be used. Some can also run on hydrogen gas.
All internal combustion engines must achieve ignition in their cylinders to create combustion. Typically engines use either a spark ignition (SI) method or a compression ignition (CI) system. In the past, other methods using hot tubes or flames have been used.

Wanna Know About The Money Giving Machine...?

2007-12-19T08:22:00.000-08:00

An automated teller machine (ATM) is a computerized telecommunications device that provides the customers of a financial institution with access to financial transactions in a public space without the need for a human clerk or bank teller. On most modern ATMs, the customer is identified by inserting a plastic ATM card with a magnetic stripe or a plastic smartcard with a chip, that contains a unique card number and some security information, such as an expiration date or CVC (CVV). Security is provided by the customer entering a personal identification number (PIN).
Using an ATM, customers can access their bank accounts in order to make cash withdrawals (or credit card cash advances) and check their account balances. ATMs are known by various casual terms including automated banking machine, cash machine, hole-in-the-wall, cashpoint or Bancomat (in Europe and Russia).
ATMs typically connect directly to their ATM Transaction Processor via either a dial-up modem over a telephone line or directly via a leased line. Leased lines are preferable to POTS lines because they require less time to establish a connection. Leased lines may be comparatively expensive to operate versus a POTS line, meaning less-trafficked machines will usually rely on a dial-up modem. That dilemma may be solved as high-speed Internet VPN connections become more ubiquitous. Common lower-level layer communication protocols used by ATMs to communicate back to the Bank include SNA over SDLC, TC500 over Async, X.25, and TCP/IP over Ethernet.

Hardware:-

An ATM is typically made up of the following devices:

* CPU (to control the user interface and transaction devices)
* Magnetic and/or Chip card reader (to identify the customer)
* PIN Pad (similar in layout to a Touch tone or Calculator keypad), often manufactured as part of a secure enclosure.
* Secure cryptoprocessor, generally within a secure enclosure.
* Display (used by the customer for performing the transaction)
* Function key buttons (usually close to the display) or a Touchscreen (used to select the various aspects of the transaction)
* Record Printer (to provide the customer with a record of their transaction)
* Vault (to store the parts of the machinery requiring restricted access)
* Housing (for aesthetics and to attach signage to)

Recently, due to heavier computing demands and the falling price of computer-like architectures, ATMs have moved away from custom hardware architectures using microcontrollers and/or application-specific integrated circuits to adopting a hardware architecture that is very similar to a personal computer. Many ATMs are now able to use operating systems such as Microsoft Windows and Linux. Although it is undoubtedly cheaper to use commercial off-the-shelf hardware, it does make ATMs vulnerable to the same sort of problems exhibited by conventional computers.

Software:-
With the migration to commodity PC hardware, standard commercial "off-the-shelf" operating systems and programming environments can be used inside of ATMs. Typical platforms used in ATM development include RMX, OS/2, and Microsoft operating systems (such as MS-DOS, PC-DOS, Windows NT, Windows 2000, Windows XP Professional, or Windows XP Embedded). Java, Linux and Unix may also be used in these environments.
Linux is also finding some reception in the ATM marketplace. An example of this is Banrisul, the largest bank in the south of Brazil, which has replaced the MS-DOS operating systems in its ATMs with Linux. Banco do Brasil is also migrating ATMs to Linux.Common application layer transaction protocols, such as Diebold 911 or 912, IBM PBM, and NCR NDC or NDC+ provide emulation of older generations of hardware on newer platforms with incremental extensions made over time to address new capabilities. Most major ATM manufacturers provide software packages that implement these protocols. Newer protocols such as IFX have yet to find wide acceptance by transaction processors.
With the move to a more standardized software base, financial institutions have been increasingly interested in the ability to pick and choose the application programs that drive their equipment. WOSA/XFS, now known as CEN XFS (or simply XFS), provides a common API for accessing and manipulating the various devices of an ATM.
J/XFS is a Java implementation of the CEN XFS API.
While the perceived benefit of XFS is similar to the Java's "Write once, run anywhere" mantra, often different ATM hardware vendors have different interpretations of the XFS standard. The result of these differences in interpretation means that ATM applications typically use a middleware to even out the differences between various platforms.
Notable XFS middleware platforms include Triton PRISM, Diebold Agilis, CR2 BankWorld, KAL Kalignite, NCR Corporation Aptra Edge, Phoenix Interactive VISTAatm, and Wincor Nixdorf Protopas.
With the move of ATMs to industry-standard computing environments, concern has risen about the integrity of the ATM's software stack.

Thinking Of buying a new and a Different bike...???

2007-12-18T06:20:00.000-08:00

At the beginning of this entry let us have a moment of nostalgia for our beloved Harleys or Ducatis. And now that the moment is over, say hello to the new generations of roaring motorcycles that are due to appear later this year. Devised by Machinheart, these new hybrid motorcycles are here to give you a glimpse of the future and maybe a breath of fresh air.
This hybrid bike goes up to 150 MPG from propane, diesel or gasoline. The biggest difference between them and the classic ride is the monocoque frame, stronger then the original one. Just like many of the hybrid motor rides designed today, this has a motor powered by the battery used for accelerating as the one powered by fuel charges the batteries.
Honda and Yamaha have stated that they will both release a hybrid that, unlike traditional bikes makes nearly no sound. I guess that would take the thrill out of the ride, no? But don’t be scared, they’ve figure out a solution: a noise generator that would imitate the deafening noise of a usual motorcycle. Now, isn’t that a bit freaky?

Have A look At Jacket Full of technologies.......

2007-12-18T06:01:00.000-08:00

Although all modern gadgets have the goal to combine good-looks with multifunctional technology and effectiveness, this is so much better then the others! Why? Because you can actually wear it! It has all the cool stuff in it like a Bluetooth and built-in MP3 player or touch sensitive control pads. But the ability through which its promoted is its compatibility with GPSoverIP. It uses a hybrid GPS technology which enables you to look for the person wearing the jacket even inside a building. The person who wears the io-Jacket can upload the information to a mobile phone or to the internet giving the watcher (probably a deranged parent) the opportunity of observing his/her every move. Londefrey, the company which produces it has sold one for humanitarian causes carrying out an auction in the purpose of saving money for the “Humans for Humans” foundation. It seems though that none other have been made for commercial purposes so we just have to sit and wait.