Run time technology

2009-10-05T02:24:00.000-07:00

Space technology is technology that is related to entering space, maintaining and using systems during spaceflight and returning people and things from space.

Teddy bears lifted to 30,085 metres above sea level on a heliumballoon in a materials experiment byCU Spaceflight and SPARKS science club. Each of the bears wore a different space suitdesigned by 11-13 year olds from SPARKS.

"Every day" technologies such as weather forecasting, remote sensing, GPS systems, satellite television, and some long distance communications systems critically rely on space infrastructure. Of sciences astronomy and Earth sciences (via remote sensing) most notably benefit from space technology.

Computers and telemetry were once leading edge technologies that might have been considered "space technology" because of their criticality to boosters and spacecraft. They existed prior to theSpace Race of the Cold War (between Russia and the U.S.A.) but their development was vastly accelerated to meet the needs of the two major superpowers' space programs. While still used today in spacecraft and missiles, the more prosaic applications such as remote monitoring (via telemetry) of patients, water plants, highway conditions, etc. and the widespread use of computers far surpasses their space applications in quantity and variety of application.

Space is such an alien environment that attempting to work in it requires new techniques and knowledge. New technologies originating with or accelerated by space-related endeavors are often subsequently exploited in other economic activities. This has been widely pointed to as beneficial by space advocates and enthusiasts favoring the investment of public funds in space activities and programs. Political opponents counter that it would be far cheaper to develop specific technologies directly if they are beneficial and scoff at this justification for public expenditures on space-related research.

2009-10-05T02:01:00.000-07:00

Advantages Of Technology

"The advantages Technology has given us outweigh the disadvantages."

Many argue that as we venture further into the frontier of technology we proceed with a slow death of society, by losing culture and ultimately a sense of self. To a certain extent this may be true, but realistically if we cease to progress we wont be able to survive. (Robert)
There are many examples of advantages and disadvantages some mentioned were " Technology has the ability to create shortcuts in working and can make tasks easier also. Solid examples are cars, calculators and phones, through technology life may be faster but is also easier. To further this point a fact brought up by Jo-ann was that diseases we have today would be and could have become epidemics, if it were not for technology being there in the field of medicine, medical advances would not have happened or would have come years later (Jo-ann). As far as transportation man has come a long way from horses and coal driven trains to computer navigable and driven cars. In boats crossing the Atlantic it took four to six months, in 747 airliner commercial jets takes ten to fifteen hours (Dana), even though they add to the pollution crisis a population accustomed to having these conveniences is still using them regardless. Among other advantages is the fact that with technology communications is a hundred times faster than without it (Ailua). Before telephones, emails and fax machines, there were trains, carriages and the pony express with the modes of traveling we have now we have been able to make the world smaller so to speak. With technology we enjoy luxuries such as movies, television, fresh food and refrigerators, ovens to cook on and bake in. And with every advantage that technology gives, it brings along with it a disadvantage we have come to depend on it more and more as we advance in the field.
If we didn't have technology we would become victim to things we were ignorant of. An...

2009-09-23T05:30:00.000-07:00

INSTRUCTIONAL TECHNOLOGY

Although there are differing opinions about the nature of instructional technology, the Commission on Instructional Technology (1970) provided the following definition:
Instructional technology is a systematic way of designing, carrying out, and evaluating the total process of learning and teaching in terms of specific objectives, based on research in human learning and communication, and employing a combination of human and nonhuman resources to bring about more effective instruction. (p. 199)
Typical applications of instructional technology may use conventional media such as videotapes, computer assisted instruction, or more complex systems, such as hypermedia programs in which computers are used to control the display of audio and visual images stored on videodisc (Blackhurst & Morse, 1996), CD-ROM and digital video discs. The use of telecommunication systems, particularly the Internet (Williams, 1995) and its World Wide Web component (Williams, 1996), have great promise for use in classrooms and for distance education. Computer software systems are now available that can be used to manage the delivery of instruction via the Web. Such systems have been used successfully to deliver instruction to undergraduate and graduate students on topics related to special education (Blackhurst, Hales, & Lahm, 1997).
It is important to note the various components of the above definition and to realize that technology is actually a tool for the delivery of instruction. In this conceptualization, technological devices are considered as means to an end and not an end in and of themselves. Use of technology cannot compensate for instruction that is poorly designed or implemented.

Clean Sky JTI

2009-09-23T05:29:00.001-07:00

Clean Sky JTI

Joint Technology Initiative (JTI): What is it?

A JTI is a new instrument created by the European Commission for the 7th Framework Programme for Research (FP7) to allow large scale and long term public private research partnerships to implement the ambitious research priorities of the Strategic Research Agenda (SRA) which are of such scale that they will require the mobilisation and management of very substantial public and private investment.

The "Clean Sky" JTI

The "Clean Sky" JTI is an industry driven 7-year research programme plan for greener generation of European Air Transport that will radically improve impact on the environment while strengthening and securing European aeronautics industry’s competitiveness.

Its purpose is to demonstrate and validate the technological breakthroughs that are necessary to reach the environmental goals set by the Advisory Council for Aeronautics Research in Europe (ACARE: the European Technology Platform for Aeronautics & Air Transport).

Goals

ACARE goals to be obtained in 2020 through the Technology Domains developed in the Clean Sky JTI:

50% reduction of CO2 emissions through drastic reduction of fuel consumption
80% reduction of NOx emissions
50% reduction of external noise
A green design, manufacturing, maintenance and disposal product life cycle

These Technology Domains are developed within six Technology Platforms, and a Technology Evaluator will evaluate the global impact of the technologies on the environment.

2009-09-23T05:19:00.000-07:00

THE EVOLUTION OF TECHNOLOGY IN EDUCATION
To many of us, the term technology conjures up visions of things such as computers, cell phones, spaceships, digital video players, computer games, advanced military equipment, and other highly sophisticated machines. Such perceptions have been acquired and reinforced through exposure to televised reports of fascinating devices and news articles about them, science fiction books and movies, and our use of equipment such as automobiles, telephones, computers, and automatic teller machines.
While this focus on devices and machines seems to be very prevalent among the general population, many educators also hold a similar perspective. Since Pressey developed the first teaching machine in 1926 (Nazzaro, 1977), technology applications in public schools and post-secondary education institutions have tended to focus on the acquisition and use of equipment such as film projectors, audio and video tape recorders, overhead projectors, and computers.
Since the early 1960s, however, a trend has emerged that is changing the way we perceive technology in education. At that time, educators began considering the concept of instructional technology. Subsequently, after considerable deliberation, a Congressional Commission on Instructional Technology (1970) concluded that technology involved more than just hardware. The Commission concluded that, in addition to the use of devices and equipment, instructional technology also involves a systematic way of designing and delivering instruction.
With the rapid development of microcomputer technology, increased research on instructional procedures, and the invention of new devices and equipment to aid those with health problems, physical disabilities, and sensory impairments, the latter third of the 20th century has borne witness to a very dramatic evolution. The current perspective is a broad one in which six types of technology are recognized: the technology of teaching, instructional technology, assistive technology, medical technology, technology productivity tools, and information technology .

2009-09-08T09:13:00.001-07:00

A parabolic dish and Stirling engine system, which concentrates sunlight to produce useful solar power.

Solar energy

Solar power Solar thermal Photovoltaics Solar vehicle

Renewable energy

Biofuel Biomass Geothermal Hydroelectricity Solar energy Tidal power Wave power Wind power
v • d • e

Solar energy is the radiant light and heat from the Sun that has been harnessed by humans since ancient times using a range of ever-evolving technologies. Solar radiation along with secondary solar resources such as wind and wave power,hydroelectricity and biomass account for most of the availablerenewable energy on Earth. Only a minuscule fraction of the available solar energy is used.

Solar power provides electrical generation by means of heat engines or photovoltaics. Once converted, its uses are limited only by human ingenuity. A partial list of solar applications includes space heating and cooling through solar architecture,potable water via distillation and disinfection, daylighting, hot water, thermal energy for cooking, and high temperature process heat for industrial purposes.

Solar technologies are broadly characterized as either passive solar or active solardepending on the way they capture, convert and distribute sunlight. Active solar techniques include the use of photovoltaic panels and solar thermal collectors (with electrical or mechanical equipment) to convert sunlight into useful outputs. Passive solar techniques include orienting a building to the Sun, selecting materials with favorable thermal mass or light dispersing properties, and designing spaces that naturally circulate air.

Cheaper LEDs

2009-08-27T08:16:00.001-07:00

Cheaper LEDs

Flexible arrays of bright inorganic LEDs could mean cheaper displays and lighting.

By Katherine Bourzac

THURSDAY, AUGUST 20, 2009

E-mail

Audio »

Favorite

A new technique makes it possible to print flexible arrays of thin inorganic light-emitting diodes for displays and lighting. The new printing process is a hybrid between the methods currently used to make inorganic and organic LEDs, and it brings some of the advantages of each, combining the flexibility, thinness and ease of manufacturing organic polymers with the brightness and long-term stability of inorganic compounds. It could be used to make high-quality flexible displays and less expensive LED lighting systems.

Stretchy screens: Arrays of tiny red inorganic LEDs can be printed on stretchable rubber substrate to conform to curves. The gold-colored wires are electrical connections and are also flexible.
Credit: Science/AAAS

Inorganic LEDs are bright and long lasting, but the expense of manufacturing them has led to them being used mainly in niche applications such as billboard-size displays for sports arenas. What's more, the manufacturing process for making inorganic LED displays is complex, because each LED must be individually cut and placed, says John Rogers, a materials science professor in the Beckman Institute at the University of Illinois at Urbana-Champaign. So display manufacturers have turned to organic materials, which can be printed and are cheaper. While LED-based lighting systems are attractive because of their low energy consumption, they remain expensive. The new printing process, developed by Rogers and described today in the journalScience, could bring down the cost of inorganic LEDs because it would require less material and simpler manufacturing techniques.

Displays based on inorganic LEDs, says Nicholas Colaneri, director of the Flexible Display Center at Arizona State University in Tempe, "are not generally economical to make." The manufacturing process involves sawing wafers of semiconducting materials such as gallium arsenide, picking and placing each piece individually using robotics, and adding electrical connections one at a time.

An Operating System for the Cloud

2009-08-27T08:13:00.000-07:00

An Operating System for the Cloud

Google is developing a new computing platform equal to the Internet era. Should Microsoft be worried?

By G. Pascal Zachary

E-mail

Audio »

Favorite

From early in their company's history, Google's founders, Larry Page and Sergey Brin, wanted to develop a computer operating system and browser.

Credit: Brian Stauffer

They believed it would help make personal computing less expensive, because Google would give away the software free of charge. They wanted to shrug off 20 years of accumulated software history (what the information technology industry calls the "legacy") by building an OS and browser from scratch. Finally, they hoped the combined technology would be an alternative to Microsoft Windows and Internet Explorer, providing a new platform for developers to write Web applications and unleashing the creativity of programmers for the benefit of the masses.

But despite the sublimity of their aspirations, Eric Schmidt, Google's chief executive, said no for six years. Google's main source of revenue, which reached $5.5 billion in its most recent quarter, is advertising. How would the project they envisioned support the company's advertising business? The question wasn't whether Google could afford it. The company is wonderfully profitable and is on track to net more than $5 billion in its current fiscal year. But Schmidt, a 20-year veteran of the IT industry, wasn't keen on shouldering the considerable costs of creating and maintaining an OS and browser for no obvious return.

Finally, two years ago, Schmidt said yes to the browser. The rationale was that quicker and more frequent Web access would mean more searches, which would translate into more revenue from ads. Then, in July of this year, Schmidt announced Google's intention to launch an operating system as well. The idea is that an OS developed with the Internet in mind will also increase the volume of Web activity, and support the browser.

Google's browser and OS both bear the name Chrome. At a year old, the browser holds a mere 2 to 3 percent share of a contested global market, in which Microsoft's Internet Explorer has a majority share and Firefox comes in second. The Chrome operating system will be released next year. Today, Windows enjoys around 90 percent of the global market for operating systems, followed by Apple's Mac OS and the freeware Linux. Does Google know what it's doing?

Ritualized Suicide
Going after Microsoft's operating system used to be hopeless. When I covered the company for the Wall Street Journal in the 1990s, I chronicled one failed attempt after another by software innovators to wrest control of the field from Bill Gates. IBM failed. Sun failed. Borland. Everybody. By the end of the 1990s, the quest had become a kind of ritualized suicide for software companies. Irresistible forces seemed to compel Gates's rivals, driving them toward self-destruction.

The networking company Novell, which Schmidt once ran, could have been one of these casualties. Perhaps Schmidt's managerial experience and intellectual engagement with computer code immunized him against the OS bug. In any case, he knew that the task of dislodging Microsoft was bigger than creating a better OS. While others misguidedly focused on the many engineering shortcomings of Windows, Schmidt knew that Microsoft was the leader not for technical reasons but for business ones, such as pricing practices and synergies between its popular office applications and Windows.

Energy-Aware Internet Routing

2009-08-27T08:07:00.000-07:00

Energy-Aware Internet Routing

Software that tracks electricity prices could slash energy costs for big online businesses.

By Will Knight

MONDAY, AUGUST 17, 2009

E-mail

Audio »

Favorite

An Internet-routing algorithm that tracks electricity price fluctuations could save data-hungry companies such as Google, Microsoft, and Amazon millions of dollars each year in electricity costs. A study from researchers at MIT, Carnegie Mellon University, and the networking company Akamai suggests that such Internet businesses could reduce their energy use by as much as 40 percent by rerouting data to locations where electricity prices are lowest on a particular day.

Data beast: Google maintains a huge datacenter in The Dalles, OR.
Credit: John Nelson

Modern datacenters gobble up huge amounts of electricity and usage is increasing at a rapid pace. Energy consumption has accelerated as applications move from desktop computers to the Internet and as information gets transferred from ordinary computers to distributed "cloud" computing services. For the world's biggest information-technology firms, this means spending upwards of $30 million on electricity every year, by modest estimates.

Asfandyar Qureshi, a PhD student at MIT, first outlined the idea of a smart routing algorithm that would track electricity prices to reduce costs in a paper presented in October 2008. This year, Qureshi and colleagues approached researchers at Akamai to obtain the real-world routing data needed to test the idea. Akamai's distributed servers cache information on behalf of many large Web sites across the US and abroad, and process some 275 billion requests per day; while the company does not require many large datacenters itself, its traffic data provides a way to model the demand placed on large Internet companies.

The researchers first analyzed 39 months of electricity price data collected for 29 major US cities. Energy prices fluctuate for a variety of reasons, including seasonal changes in supply, fuel price hikes, and changes in consumer demand, and the researchers saw a surprising amount of volatility, even among geographically close locations.

"The thing that surprised me most was that there was no one place that was always cheapest," says Bruce Maggs, vice president of research at Akamai, who contributed to the project while working as a professor at Carnegie Mellon and is currently a professor at Duke University. "There are large fluctuations on a short timescale."

2009-08-03T18:59:00.001-07:00

GLOBAL WARMING

Global mean surface temperature difference from the average for 1961–1990

Mean surface temperature change for the period 1999 to 2008 relative to the average temperatures from 1940 to 1980

Global warming is the increase in the average temperature of the Earth's near-surface air and oceans since the mid-20th century and its projected continuation. Global surface temperature increased 0.74 ± 0.18 °C (1.33 ± 0.32 °F) during the last century.^[1]^[A] TheIntergovernmental Panel on Climate Change (IPCC) concludes that increasing greenhouse gas concentrations resulting from human activity such as fossil fuel burning and deforestation caused most of the observed temperature increase since the middle of the 20th century.^[1] The IPCC also concludes that variations in natural phenomena such as solar radiation and volcanoes produced most of the warming from pre-industrial times to 1950 and had a small cooling effect afterward.^[2]^[3] These basic conclusions have beenendorsed by more than 45 scientific societies and academies of science,^[B] including all of the national academies of science of themajor industrialized countries.^[4] A small number of scientists dispute the consensus view.

Climate model projections summarized in the latest IPCC report indicate that the global surface temperature will probably rise a further 1.1 to 6.4 °C (2.0 to 11.5 °F) during the twenty-first century.^[1]The uncertainty in this estimate arises from the use of models with differing sensitivity to greenhouse gas concentrations and the use of differing estimates of future greenhouse gas emissions. Some otheruncertainties include how warming and related changes will vary from region to region around the globe. Most studies focus on the period up to the year 2100. However, warming is expected to continue beyond 2100 even if emissions stop, because of the large heat capacity of the oceans and the long lifetime ofcarbon dioxide in the atmosphere.^[5]^[6]

An increase in global temperature will cause sea levels to rise and will change the amount and pattern ofprecipitation, probably including expansion of subtropical deserts.^[7] The continuing retreat of glaciers,permafrost and sea ice is expected, with warming being strongest in the Arctic. Other likely effects include increases in the intensity of extreme weather events, species extinctions, and changes inagricultural yields.

Political and public debate continues regarding climate change, and what actions (if any) to take in response. The available options are mitigation to reduce further emissions; adaptation to reduce the damage caused by warming; and, more speculatively, geoengineering to reverse global warming. Most national governments have signed and ratified the Kyoto Protocol aimed at reducing greenhouse gasemissions.

2009-07-30T22:37:00.000-07:00

WATER PURIFICATION AND SIMPLE TECHNOLOGY
Access to clean drinking water is taken for granted in most countries across the world. However, in many third world countries clean drinking water is not always available. Many people, especially children, suffer from diseases contracted from drinking water infected with salmonella, E-coli bacteria and many other forms of bacteria. Drinking impure water can be fatal and at best cause severe diarrhoea. Diarrhoea dehydrates the body and often the sufferer drinks more contaminated water in an attempt to replace the water his/her body has lost.A basic water filter can purify ‘dirty’ water making much safer to drink. The filter is based on simple technology and one example is shown below. It is composed of quite common materials and is relatively easy to put together. Technology does not always need to be complex or computer controlled to be effective and useful.
The ‘dirty’ water is poured into the top of a tank which contains layers of sand, charcoal and gravel. As the water sinks through the various layers the bacteria and dirt are removed. The clean water flows through a hose/pipe into a ‘clean’ water storage tank. The water is now safe to drink. This is simple technology helping people live safer and longer lives.

2009-07-29T22:25:00.001-07:00

Have a look at the photograph on the right. Can you imagine how long it would take a skilled worker to ‘carve’ this shape out of wood or a soft material - it would probably take a full day. We will be going through its manufacture, one step at a time using a CNC machine (next page). How long do you think manufacturing this product with a CNC machine will take ?

THE CNC MACHINE

The VICE: This holds the material to be cut or shaped. Material must be held securely otherwise it may 'fly' out of the vice when the CNC begins to machine. Normally the vice will be like a clamp that holds the material in the correct position.

The GUARD: The guard protects the person using the CNC. When the CNC is machining the material small pieces can be 'shoot' off the material at high speed. This could be dangerous if a piece hit the person operating the machine. The guard completely encloses the the dangerous areas of the CNC.

The CHUCK: This holds the material that is to be shaped. The material must be placed in it very carefully so that when the CNC is working the material is not thrown out at high speed.

The MOTOR: The motor is enclosed inside the machine. This is the part that rotates the chuck at high speed.

The LATHE BED: The base of the machine. Usually a CNC is bolted down so that it cannot move through the vibration of the machine when it is working.

The CUTTING TOOL: This is usually made from high quality steel and it is the part that actually cuts the material to be shaped.

1. Draw a small CNC machine and label the most important parts.
2. List the safety factors that people must be aware of before they operate a CNC or similar machine

ALTERNATIVE ENERGY SOURCES

2009-07-23T08:32:00.000-07:00

SOLAR ENERGY
Solar power is energy from the sun and without its presence all life on earth would end. Solar energy has been looked upon as a serious source of energy for many years because of the vast amounts of energy that are made freely available, if harnessed by modern technology.A simple example of the power of the sun can be seen by using a magnifying glass to focus the suns rays on a piece of paper. Before long the paper ignites into flames.
This is one way of using the suns energy, but flames are dangerous and difficult to control. A much safer and practical way of harnessing the suns energy is to use the suns power to heat up water.
A magnifying glass can be used to heat up a small amount of water। A short piece of copper tube is sealed at one end and filled with water. A magnifying glass is then used to warm up the pipe. Using more than one magnifying glass will increase the temperature more rapidly. After a relatively short time the temperature of the water increases. Continuing to heat the water will cause water vapour to appear at the top of the tube. In theory, with enough patience, several magnifying glasses and very strong sun light enough heat should be generated to boil the water, producing steam. This is one way of harnessing solar power.

AIR MOVES FORMING WINDS
Wind power is generated by moving air. As the sun heats the land, the air above also warms and rises. Cold air then replaces the rising air. This creates the winds that we feel most days of the year. The diagram below shows how this ‘system’ works.Air tends to warm at a faster rate over land because the land retains its heat. Over the sea the air warms more slowly as heat by the sun is slowly cooled by the cold water. If you visit the seaside or coastal area you will probably find that the weather is more breezy or windy than inland. This is because the warm air rises over the land and cold air over the sea replaces it.

Throughout history people have taken advantage of the power of wind। Sail vessels have been used to travel along and across rivers, seas and lakes. For example, the Vikings used long ships with sail from Europe to England, Scotland, Wales and Ireland. It is also believed that they travelled even as far as North America, all through the use of wind power.It is also known that the Chinese over 1500 years ago had large sailing vessels and travelled as far as Africa.It is difficult to think of a time when people have not made great use of the power of the wind.

SEA POWER
The power of the tide can be seen in this photograph. It shows people running for their lives from a powerful tidal wave which has crashed over a coastal/river wall (China 2000). If tidal power can be harnessed electricity can be produced in large quantities.

The Earth is covered mainly by water। The seas as we call them, have currents and tides that circulate round the world. This vast amount of moving water produces immense amounts of energy. Countries like Britain that are surrounded by powerful seas and oceans are ideally placed to convert the energy of tides, sea currents and waves to produce electrical energy. The main problem in harnessing sea power is that it is not easy and usually means investment of large amounts of money. Also, quite advanced engineering and technology are required to convert sea power to electrical power.The power of the sea can be harnessed in three main ways; through the energy of waves, the energy of sea currents and tides.

DAMS / HYDRO ELECTRICITY
Water has been used to power industry for hundreds years. The example below shows a water wheel being driven round by a river / stream. As the water wheel turns, a shaft running through its centre would be used to power machines through a range of pulleys. This was the main form of power during the early years of the Industrial Revolution.
Water wheels were the fore-runner of our modern day water driven electrical turbines.
To increase the power provided by water a dam is added। This is seen in the diagram below. The dam allows a ‘head’ of water to build up. The water can be release when power is needed to drive machines inside the building/factory. This system provides more power because:1. A powerful ‘head’ of water is built up behind the dam.2. When the water is released, it is directed to the top of the water wheel. The wheel spins faster because gravity aids the falling water, pushing the wheel round at a higher speed.

NUCLEAR POWER GENERATION
Nuclear Power Stations use a fuel called uranium, a relatively common material. Energy is released from uranium when an atom is split by a neutron. The uranium atom is split into two and as this happens energy is released in the form of radiation and heat. This nuclear reaction is called the fission process
In a nuclear power station the uranium is first formed into pellets and then into long rods. The uranium rods are kept cool by submerging them in water. When they are removed from the water a nuclear reaction takes place causing heat. The amount of heat required is controlled by raising and lowering the rods. If more heat is required the rods are raised further out of the water and if less is needed they lower further into it.
GENERAL ADVANTAGES AND DISADVANTAGES OFNUCLEAR POWER GENERATION

DISADVANTAGES:1. Nuclear power is a controversial method of producing electricity. Many people and environmental organisations are very concerned about the radioactive fuel it needs. 2. There have been serious accidents with a small number of nuclear power stations. The accident at Chernobyl (Ukraine) in 1986, led to 30 people being killed and over 100,000 people being evacuated. In the preceding years another 200,00 people were resettled away from the radioactive area. Radiation was even detected over a thousand miles away in the UK as a result of the Chernobyl accident. It has been suggested that over time 2500 people died as a result of the accident. 3. There are serious questions to be answered regarding the storage of radioactive waste produced through the use of nuclear power. Some of the waste remains radioactive (dangerous) for thousands of years and is currently stored in places such as deep caves and mines.4. Storing and monitoring the radioactive waste material for thousands of years has a high cost.5. Nuclear powered ships and submarines pose a danger to marine life and the environment. Old vessels can leak radiation if they are not maintained properly or if they are dismantled carelessly at the end of their working lives.6. Many people living near to nuclear power stations or waste storage depots are concerned about nuclear accidents and radioactive leaks. Some fear that living in these areas can damage their health, especially the health of young children.7. Many Governments fear that unstable countries that develop nuclear power may also develop nuclear weapons and even use them.ADVANTAGES:1. The amount of electricity produced in a nuclear power station is equivalent to that produced by a fossil fuelled power station.2. Nuclear power stations do not burn fossil fuels to produce electricity and consequently they do not produce damaging, polluting gases. 3. Many supporters of nuclear power production say that this type of power is environmentally friendly and clean. In a world that faces global warming they suggest that increasing the use of nuclear power is the only way of protecting the environment and preventing catastrophic climate change. 4. Many developed countries such as the USA and the UK no longer want to rely on oil and gas imported from the Middle East, a politically unstable part of the world.5. Countries such as France produce approximately 90 percent of their electricity from nuclear power and lead the world in nuclear power generating technology - proving that nuclear power is an economic alternative to fossil fuel power stations. 6. Nuclear reactors can be manufactured small enough to power ships and submarines. If this was extended beyond military vessels, the number of oil burning vessels would be reduced and consequently pollution.

DIGITAL ELECTRONICS - LOGIC CIRCUITS

2009-07-23T08:27:00.000-07:00

Most modern electronic devices such as mobile telephones and computers depend on digital electronics. In fact, most electronics about the home and in industry depend on digital electronics to work.Digital electronics normally based on ‘logic circuits’. These circuits depend on pulses of electricity to make the circuit work. For instance, if current is present - this is represented as ‘1’. If current is not present, this is represented as ‘0’. Digital electronics is based on a series of 1s and 0s.

A good example of a digital electronic system is a mobile phone. As you speak into the phone, the digital electronic circuits it contains converts your voice into a series of electronic pulses (or 1s and 0s). These are transmitted and the receiving mobile phone then converts the digital pulses back into your voice. Digital circuits are used because they are efficient and work well, also, digital signals are easier to transmit than actual sound (for example a persons voice).

The various parts of a computer communicate through the use of electronic pulses (1s and 0s). Consequently digital logic circuits are ideal for the internal electronics. The main part of the computer is the motherboard. This is a complex piece of electronics that processes all the important data. For instance, when word processing, it is very important to display letters and words on the monitor. The motherboard generates the individual letters on the monitor by sending a series of 1s and 0s to the screen.
(For more information regarding digital signals see computer control)
When the computer operator presses the letter ‘H’ on the keyboard, the motherboard converts this into a digital signal composed of 1s and 0s. The ‘H’ in the form of 1s and 0s is displayed on the monitor.When you word-process a paragraph of writing all the letters/words are displayed on the monitor in a similar way. In reality the letters are not composed of 1s and 0s but as black or white pixels

MODULAR ELECTRONICS

2009-07-23T08:20:00.000-07:00

When building a circuit it is a good idea to treat it as being made up of modules or parts. For example you may want a circuit to be composed of a switch and a bulb. To make it easier to design the circuit it is better if it is treated as two separate parts, a switch circuit and a bulb circuit. These are then joined together - to produce one completed circuit.
Circuits are often built as modules with each doing a specific job. For example, a sensor module, a transistor module, a buzzer module etc...... When these are connected together they become a single integrated circuit.

Two simple modules are seen opposite and they are clearly labelled. They can be rearranged to produce a complete circuit. When the switch is pressed the bulb lights (see below).Each module has a top rail which is positive and a lower rail which is 0 volts or negative.

The modules are linked together by electrical wires and they fit into the positive or negative connections on the electronic boards/modules. Different makes of electronic kits are available and each allows pupils to build up circuits, test them or experiment and finally to dismantle the modules so that another pupil can use them in the future.In this way circuits can be built without the need to solder and without wasting time linking each individual component using traditional methods.
Below is a temperature sensor circuit. When the temperature falls the resistance of the thermistor falls and a bulb lights. Notice how the modules are put together to form the completed circuit.

The temperature sensor is connected to a transistor which is then connected to a bulb. The transistor allows sharp switching of the bulb so that when the temperature falls the bulb comes on immediately and when it rises it goes off just as quickly. Can you draw the circuit as a circuit diagram ?

QUESTIONS
Below are some modules that can be put together to form completed circuits. Cut them out with a scissors and join them to complete the circuit questions on Sheet 3. If you require any modules that are not on this sheet, design them yourself and add them to the ones below.

1. This question refers to the example ‘temperature sensor circuit’ near the top of this section. A. Redesign the transistor module and bulb module so that they form one module.B. Draw the completed temperature sensor and transistor/bulb modules connected together. Explain how the completed circuit works.C. Draw a new temperature module, this time one that ‘triggers’ the transistor module when the temperature rises.2. A. It is found that the bulb in the completed temperature circuit does not light because the output of the single transistor is too weak. Design a new module that will provide a stronger output. B. What is this new module called ?C. Explain how this circuit works.3. Design a ‘potential divider’ module. The module is for a nine volt supply and should allow six volts to be drawn from it.4. Design a simple game or toy for a very young child. It can involve sound, lights, a motor etc... Produce a simple, clear diagram and an explanation.5. Design the circuit(s) for the toy using modules and then draw the completed circuit as a ‘circuit diagram’.You may need to design your own individual modules. Look at the photocopied sheets that have been given out in previous weeks. (Suggestion - show your knowledge by using relays, LEDs, motors etc... alter sensors so that they can be incorporated). Note, it is possible to set up components in ‘parallel’ so that they work together. (example seen below).

Remember to show your understanding of components such as relays and circuits that include ‘Darlington Pairs’ etc.... The examiner cannot give you marks for your understanding of electronics if you do not show it on paper.

Drawing Techniques

2009-07-23T08:12:00.000-07:00

COLOURING TECHNIQUESPENCILS2H pencils - Use ordinary pencils to draw and sketch.Colouring pencils - Use pencils to colour drawings and to draw the outline of designs.CARDOverlays/backing - Use card on top of card, you could glue together two different pieces of card and then place a design brief or something similar on the top. The card will be a backing.Colour placed on card - Try shading card with a coloured pencil, use a dark colour of card and shade it with a light shade of pencil. Use the result to back text/writing.Composite drawings - See the examples in class. Drawings constructed from different colours of card can be quite striking.FELT PENS
Brush and fine line pens - see craft knife project Brush and fine line pens - See pen project.SHADINGLine shading - see cylinder examples.
Line Shading - see flat surface examples Full shading - shade from dark to light, see examplesBLACK PEN - Use a fine black pen to draw designs.PAINTTry colour wash with water based paint.Use an airbrush to spray paint on to the paper.TRANSPARENCIESUse OHP transparencies to build up a drawing.INFORMATION TECHNOLOGYUse a range of I.T. skills including; word processing and graphics software throughout your project.

DRAWING TECHNIQUESSketch with pencils.Sketch with pens (black ink).Use pictograms and graphs.2D Drawings - front or side views.3D Drawings - Isometric - Oblique - Single point perspective and Estimated Perspective - Two point perspectiveExploded Drawings -
1. Exploded Views - 1
2. Exploded Views - 2
3. Exploded Views - 3
4. Exploded Views - 4
draw designs that are ‘in bits’, or ‘taken apart’ so that all the parts of the design can be seen easily.Sectioned views - Draw a sectional view of an idea or solution.Working Drawing - draw the front. side and plan elevations of the final solution.Use a range of lettering stylesAlways add plenty of notes to all your drawings / pictures, including collected research.Dynamic presentations - produce drawings that have parts that move e.g. ‘pop-up card’ designs or parts that rotate.Modelling - produce models of selected designs.Produce a final model of your chosen solution. This must look realistic and be well made.
Sample Models
Card Based Models
Architectural Models
Computer Generated Models
Computer Generated Systems Model (Spreadsheets)
HAVE YOU INCLUDED COMPUTER AIDED DESIGN ?