Thursday 24 May 2012

MICROPROCESSOR

The computer you are using to read this page uses a microprocessor to do its work. The microprocessor is the heart of any normal computer, whether it is a desktop machine, a server or a laptop. The microprocessor you are using might be a Pentium, a K6, a PowerPC, a Sparc or any of the many other brands and types of microprocessors, but they all do approximately the same thing in approximately the same way.
A microprocessor -- also known as a CPU or central processing unit -- is a complete computation engine that is fabricated on a single chip. The first microprocessor was the Intel 4004, introduced in 1971. The 4004 was not very powerful -- all it could do was add and subtract, and it could only do that 4 bits at a time. But it was amazing that everything was on one chip. Prior to the 4004, engineers built computers either from collections of chips or from discrete components (transistors wired one at a time). The 4004 powered one of the first portable electronic calculators. 
The first microprocessor to make it into a home computer was the Intel 8080, a complete 8-bit computer on one chip, introduced in 1974. The first microprocessor to make a real splash in the market was the Intel 8088, introduced in 1979 and incorporated into the IBM PC (which first appeared around 1982). If you are familiar with the PC market and its history, you know that the PC market moved from the 8088 to the 80286 to the 80386 to the 80486 to the Pentium to the Pentium II to the Pentium III to the Pentium 4. All of these microprocessors are made by Intel and all of them are improvements on the basic design of the 8088. The Pentium 4 can execute any piece of code that ran on the original 8088, but it does it about 5,000 times faster!  
The following table helps you to understand the differences between the different processors that Intel has introduced over the years.



The Intel 8080 was the first microprocessor in a home computer.

Since 2004, Intel has introduced microprocessors with multiple cores and millions more transistors. But even these microprocessors follow the same general rules as earlier chips. Additional information about this table:

  • The date is the year that the processor was first introduced. Many processors are re-introduced at higher clock speeds for many years after the original release date.
  • Transistors is the number of transistors on the chip. You can see that the number of transistors on a single chip has risen steadily over the years.
  • Microns is the width, in microns, of the smallest wire on the chip. For comparison, a human hair is 100 microns thick. As the feature size on the chip goes down, the number of transistors rises.
  • Clock speed is the maximum rate that the chip can be clocked at. Clock speed will make more sense in the next section.
  • Data Width is the width of the ALU. An 8-bit ALU can add/subtract/multiply/etc. two 8-bit numbers, while a 32-bit ALU can manipulate 32-bit numbers. An 8-bit ALU would have to execute four instructions to add two 32-bit numbers, while a 32-bit ALU can do it in one instruction. In many cases, the external data bus is the same width as the ALU, but not always. The 8088 had a 16-bit ALU and an 8-bit bus, while the modern Pentiums fetch data 64 bits at a time for their 32-bit ALUs.
  • MIPS stands for "millions of instructions per second" and is a rough measure of the performance of a CPU. Modern CPUs can do so many different things that MIPS ratings lose a lot of their meaning, but you can get a general sense of the relative power of the CPUs from this column.
What's a Chip?
A chip is also called an integrated circuit. Generally it is a small, thin piece of silicon onto which the transistors making up the microprocessor have been etched. A chip might be as large as an inch on a side and can contain tens of millions of transistors. Simpler processors might consist of a few thousand transistors etched onto a chip just a few millimeters square.
From this above table you can see that, in general, there is a relationship between clock speed and MIPS. The maximum clock speed is a function of the manufacturing process and delays within the chip. There is also a relationship between the number of transistors and MIPS. For example, the 8088 clocked at 5 MHz but only executed at 0.33 MIPS (about one instruction per 15 clock cycles). Modern processors can often execute at a rate of two instructions per clock cycle.
To understand how a microprocessor works, it is helpful to look inside and learn about the logic used to create one. In the process you can also learn about assembly language -- the native language of a microprocessor -- and many of the things that engineers can do to boost the speed of a processor.
A microprocessor executes a collection of machine instructions that tell the processor what to do. Based on the instructions, a microprocessor does three basic things:
  • Using its ALU (Arithmetic/Logic Unit), a microprocessor can perform mathematical operations like addition, subtraction, multiplication and division. Modern microprocessors contain complete floating point processors that can perform extremely sophisticated operations on large floating point numbers.
  • A microprocessor can move data from one memory location to another.
  • A microprocessor can make decisions and jump to a new set of instructions based on those decisions.
There may be very sophisticated things that a microprocessor does, but those are its three basic activities. The following diagram shows an extremely simple microprocessor capable of doing those three things:



This is about as simple as a microprocessor gets. This microprocessor has:
  • An address bus (that may be 8, 16 or 32 bits wide) that sends an address to memory
  • A data bus (that may be 8, 16 or 32 bits wide) that can send data to memory or receive data from memory
  • An RD (read) and WR (write) line to tell the memory whether it wants to set or get the addressed location
  • A clock line that lets a clock pulse sequence the processor
  • A reset line that resets the program counter to zero (or whatever) and restarts execution
Let's assume that both the address and data buses are 8 bits wide in this example.
Here are the components of this simple microprocessor:
  • Registers A, B and C are simply latches made out of flip-flops.
  • The address latch is just like registers A, B and C.
  • The program counter is a latch with the extra ability to increment by 1 when told to do so, and also to reset to zero when told to do so.
  • The ALU could be as simple as an 8-bit adder, or it might be able to add, subtract, multiply and divide 8-bit values. Let's assume the latter here.
  • The test register is a special latch that can hold values from comparisons performed in the ALU. An ALU can normally compare two numbers and determine if they are equal, if one is greater than the other, etc. The test register can also normally hold a carry bit from the last stage of the adder. It stores these values in flip-flops and then the instruction decoder can use the values to make decisions.
  • There are six boxes marked "3-State" in the diagram. These are tri-state buffers. A tri-state buffer can pass a 1, a 0 or it can essentially disconnect its output (imagine a switch that totally disconnects the output line from the wire that the output is heading toward). A tri-state buffer allows multiple outputs to connect to a wire, but only one of them to actually drive a 1 or a 0 onto the line.
  • The instruction register and instruction decoder are responsible for controlling all of the other components.
Although they are not shown in this diagram, there would be control lines from the instruction decoder that would:
  • Tell the A register to latch the value currently on the data bus
  • Tell the B register to latch the value currently on the data bus
  • Tell the C register to latch the value currently output by the ALU
  • Tell the program counter register to latch the value currently on the data bus
  • Tell the address register to latch the value currently on the data bus
  • Tell the instruction register to latch the value currently on the data bus
  • Tell the program counter to increment
  • Tell the program counter to reset to zero
  • Activate any of the six tri-state buffers (six separate lines)
  • Tell the ALU what operation to perform
  • Tell the test register to latch the ALU's test bits
  • Activate the RD line
  • Activate the WR line
Coming into the instruction decoder are the bits from the test register and the clock line, as well as the bits from the instruction register.

Microprocessor Memory

Microprocessor memory helps with the microprocessors basic functions. Learn about microprocessor memory, ROM, BIOS and what the boot sector is.
ROM chip
The previous section talked about the address and data buses, as well as the RD and WR lines. These buses and lines connect either to RAM or ROM -- generally both. In our sample microprocessor, we have an address bus 8 bits wide and a data bus 8 bits wide. That means that the microprocessor can address (28) 256 bytes of memory, and it can read or write 8 bits of the memory at a time. Let's assume that this simple microprocessor has 128 bytes of ROM starting at address 0 and 128 bytes of RAM starting at address 128.
ROM stands for read-only memory. A ROM chip is programmed with a permanent collection of pre-set bytes. The address bus tells the ROM chip which byte to get and place on the data bus. When the RD line changes state, the ROM chip presents the selected byte onto the data bus.
RAM stands for random-access memory. RAM contains bytes of information, and the microprocessor can read or write to those bytes depending on whether the RD or WR line is signaled. One problem with today's RAM chips is that they forget everything once the power goes off. That is why the computer needs ROM.
Microprocessor memory helps with the microprocessors basic functions. Learn about microprocessor memory, ROM, BIOS and what the boot sector is.
RAM chip
By the way, nearly all computers contain some amount of ROM (it is possible to create a simple computer that contains no RAM -- many microcontrollers do this by placing a handful of RAM bytes on the processor chip itself -- but generally impossible to create one that contains no ROM). On a PC, the ROM is called the BIOS (Basic Input/Output System). When the microprocessor starts, it begins executing instructions it finds in the BIOS. The BIOS instructions do things like test the hardware in the machine, and then it goes to the hard disk to fetch the boot sector . This boot sector is another small program, and the BIOS stores it in RAM after reading it off the disk. The microprocessor then begins executing the boot sector's instructions from RAM. The boot sector program will tell the microprocessor to fetch something else from the hard disk into RAM, which the microprocessor then executes, and so on. This is how the microprocessor loads and executes the entire operating system.

Microprocessor Performance and Trends

The number of transistors available has a huge effect on the performance of a processor. As seen earlier, a typical instruction in a processor like an 8088 took 15 clock cycles to execute. Because of the design of the multiplier, it took approximately 80 cycles just to do one 16-bit multiplication on the 8088. With more transistors, much more powerful multipliers capable of single-cycle speeds become possible.
More transistors also allow for a technology called pipelining. In a pipelined architecture, instruction execution overlaps. So even though it might take five clock cycles to execute each instruction, there can be five instructions in various stages of execution simultaneously. That way it looks like one instruction completes every clock cycle.
Many modern processors have multiple instruction decoders, each with its own pipeline. This allows for multiple instruction streams, which means that more than one instruction can complete during each clock cycle. This technique can be quite complex to implement, so it takes lots of transistors.
Trends
The trend in processor design has primarily been toward full 32-bit ALUs with fast floating point processors built in and pipelined execution with multiple instruction streams. The newest thing in processor design is 64-bit ALUs, and people are expected to have these processors in their home PCs in the next decade. There has also been a tendency toward special instructions (like the MMX instructions) that make certain operations particularly efficient, and the addition of hardware virtual memory support and L1 caching on the processor chip. All of these trends push up the transistor count, leading to the multi-million transistor powerhouses available today. These processors can execute about one billion instructions per second! 

64-bit Microprocessors

64 bit processors have entered the mainstream. Find out how 64 bit processors work and why they can handle an almost infinite amount of RAM.
Photo courtesy AMD
Sixty-four-bit processors have been with us since 1992, and in the 21st century they have started to become mainstream. Both Intel and AMD have introduced 64-bit chips, and the Mac G5 sports a 64-bit processor. Sixty-four-bit processors have 64-bit ALUs, 64-bit registers, 64-bit buses and so on.
One reason why the world needs 64-bit processors is because of their enlarged address spaces. Thirty-two-bit chips are often constrained to a maximum of 2 GB or 4 GB of RAM access. That sounds like a lot, given that most home computers currently use only 256 MB to 512 MB of RAM. However, a 4-GB limit can be a severe problem for server machines and machines running large databases. And even home machines will start bumping up against the 2 GB or 4 GB limit pretty soon if current trends continue. A 64-bit chip has none of these constraints because a 64-bit RAM address space is essentially infinite for the foreseeable future -- 2^64 bytes of RAM is something on the order of a billion gigabytes of RAM.
With a 64-bit address bus and wide, high-speed data buses on the motherboard, 64-bit machines also offer faster I/O (input/output) speeds to things like hard disk drives and video cards. These features can greatly increase system performance.
Servers can definitely benefit from 64 bits, but what about normal users? Beyond the RAM solution, it is not clear that a 64-bit chip offers "normal users" any real, tangible benefits at the moment. They can process data (very complex data features lots of real numbers) faster. People doing video editing and people doing photographic editing on very large images benefit from this kind of computing power. High-end games will also benefit, once they are re-coded to take advantage of 64-bit features. But the average user who is reading e-mail, browsing the Web and editing Word documents is not really using the processor in that way.


Monday 21 May 2012

AIR CONDITIONER


picture of air conditioner
                                         Air conditioners and refrigerators work the same way. Instead of cooling just the small, insulated space inside of a refrigerator, an air conditioner cools a room, a whole house, or an entire business.
Air conditioners use chemicals that easily convert from a gas to a liquid and back again. This chemical is used to transfer heat from the air inside of a home to the outside air.
The machine has three main parts. They are a compressor, a condenser and an evaporator. The compressor and condenser are usually located on the outside air portion of the air conditioner. The evaporator is located on the inside the house, sometimes as part of a furnace. That's the part that heats your house.
The working fluid arrives at the compressor as a cool, low-pressure gas. The compressor squeezes the fluid. This packs the molecule of the fluid closer together. The closer the molecules are together, the higher its energy and its temperature.
The working fluid leaves the compressor as a hot, high pressure gas and flows into the condenser. If you looked at the air conditioner part outside a house, look for the part that has metal fins all around. The fins act just like a radiator in a car and helps the heat go away, or dissipate, more quickly.
When the working fluid leaves the condenser, its temperature is much cooler and it has changed from a gas to a liquid under high pressure. The liquid goes into the evaporator through a very tiny, narrow hole. On the other side, the liquid's pressure drops. When it does it begins to evaporate into a gas.
As the liquid changes to gas and evaporates, it extracts heat from the air around it. The heat in the air is needed to separate the molecules of the fluid from a liquid to a gas.
The evaporator also has metal fins to help in exchange the thermal energy with the surrounding air.
By the time the working fluid leaves the evaporator, it is a cool, low pressure gas. It then returns to the compressor to begin its trip all over again.
Connected to the evaporator is a fan that circulates the air inside the house to blow across the evaporator fins. Hot air is lighter than cold air, so the hot air in the room rises to the top of a room.
There is a vent there where air is sucked into the air conditioner and goes down ducts. The hot air is used to cool the gas in the evaporator. As the heat is removed from the air, the air is cooled. It is then blown into the house through other ducts usually at the floor level.
This continues over and over and over until the room reaches the temperature you want the room cooled to. The thermostat senses that the temperature has reached the right setting and turns off the air conditioner. As the room warms up, the thermostat turns the air conditioner back on until the room reaches the temperature.

Friday 18 May 2012

PETROL ENGINE

The working of an internal combustion engine is divided into four stages called four strokes of the engine and hence the engine is called a four stroke engine.

The intake stroke :
When the engine starts, the piston moves downwards in the cylinder, because of which a region of low pressure is created in the cylinder, above the piston. At this moment, the intake valve opens and the fuel mixture(petrol vapour and air mixture) is sucked into the cylinder from the carburettor.


Intake stroke


The compression stroke :
When the sufficient amount of the fuel mixture (petrol vapour and air mixture) has entered the cylinder, the intake valve gets closed. The piston is then forced to move upwards which compresses the fuel-mixture to about one-eighth of its original volume. Higher the compression ratio, more will be the efficiency of the engine.
Compression stroke


The power stroke :
Before the piston completes its upward movement, compressing the petrol vapour and air mixture, the spark plug produces a little electric spark inside the cylinder and this spark sets fire to the petrol-air mixture. The petrol vapour burns quickly in a little explosion, producing a large volume of gases and enormous heat. The heat thus produced expands the gases rapidly. The pressure of rapidly expanding hot gases pushes the piston downward with a great force. The piston pushes the piston rod and the piston rod pushes the crank shaft. The crank shaft is joined to the wheels of a car. When the crank shaft turns, the wheels rotate and move the car.
Power stroke


The exhaust stroke:
When the piston has been pushed to the bottom of the cylinder by the hot expanding gases in the power stroke, then the exhaust valve opens. After that, due to the momentum gained by the wheels, the piston is pushed upwards. The upward movement of the piston, expels the spent gases through the exhaust valve into the atmosphere, carrying away the unused heat. The exhaust valve then closes, the intake valve opens up, and the above four strokes of the engine are repeated again and again.
Exhaust stroke

Thursday 17 May 2012

MAGLEV TRAINS


                        The first commercial maglev line made its debut in December of 2003. Learn about it and other maglev lines in the works.
                               If you'v­e been to an airport lately, you've probably noticed that air travel is becoming more and more congested. Despite frequent delays, airplanes still provide the fastest way to travel hundreds or thousands of miles. Passenger air travel revolutionized the transportation industry in the last century, letting people traverse great distances in a matter of hours instead of days or weeks.
The only alternatives to airplanes -- feet, cars, buses, boats and conventional trains -- are just too slow for today's fast-paced society. However, there is a new form of transportation that could revolutionize transportation of the 21st century the way airplanes did in the 20th century.
A few countries are using powerful electromagnets to develop high-speed trains, called maglev trains. Maglev is short for magnetic levitation, which means that these trains will float over a guideway using the basic principles of magnets to replace the old steel wheel and track trains. In this article, you will learn how electromagnetic propulsion works, how three specific types of maglev trains work and where you can ride one of these trains.

Electromagnetic Suspension (EMS)

­If you've ever played with magnets, you know that opposite poles attract and like poles repel each other. This is the basic principle behind electromagnetic propulsion. Electromagnets are similar to other magnets in that they attract metal objects, but the magnetic pull is temporary. As you can read about in How Electromagnets Work, you can easily create a small electromagnet yourself by connecting the ends of a copper wire to the positive and negative ends of an AA, C or D-cell battery. This creates a small magnetic field. If you disconnect either end of the wire from the battery, the magnetic field is taken away.
The magnetic field created in this wire-and-battery experiment is the simple idea behind a maglev train rail system. There are three components to this system:
  • A large electrical power source
  • Metal coils lining a guideway or track
  • Large guidance magnets attached to the underside of the train
­The big difference between a maglev train and a conventional train is that maglev trains do not have an engine -- at least not the kind of engine used to pull typical train cars along steel tracks. The engine for maglev trains is rather inconspicuous. Instead of using fossil fuels, the magnetic field created by the electrified coils in the guideway walls and the track combine to propel the train.

Above is an image of the guideway for the Yamanashi maglev test line in Japan.
Photos courtesy Railway Technical Research Institute.

 

The Maglev Track

The magnetized coil running along the track, called a guideway, repels the large magnets on the train's undercarriage, allowing the train to levitate between 0.39 and 3.93 inches (1 to 10 cm) above the guideway. Once the train is levitated, power is supplied to the coils within the guideway walls to create a unique system of magnetic fields that pull and push the train along the guideway. The electric current supplied to the coils in the guideway walls is constantly alternating to change the polarity of the magnetized coils. This change in polarity causes the magnetic field in front of the train to pull the vehicle forward, while the magnetic field behind the train adds more forward thrust.
Maglev trains float on a cushion of air, eliminating friction. This lack of friction and the trains' aerodynamic designs allow these trains to reach unprecedented ground transportation speeds of more than 310 mph (500 kph), or twice as fast as Amtrak's fastest commuter train. In comparison, a Boeing-777 commercial airplane used for long-range flights can reach a top speed of about 562 mph (905 kph). Developers say that maglev trains will eventually link cities that are up to 1,000 miles (1,609 km) apart. At 310 mph, you could travel from Paris to Rome in just over two hours.
Germany and Japan are both developing maglev train technology, and both are currently testing prototypes of their trains. (The German company "Transrapid International" also has a train in commercial use -- more about that in the next section.) Although based on similar concepts, the German and Japanese trains have distinct differences. In Germany, engineers have developed an electromagnetic suspension (EMS) system, called Transrapid. In this system, the bottom of the train wraps around a steel guideway. Electromagnets attached to the train's undercarriage are directed up toward the guideway, which levitates the train about 1/3 of an inch (1 cm) above the guideway and keeps the train levitated even when it's not moving. Other guidance magnets embedded in the train's body keep it stable during travel. Germany has demonstrated that the Transrapid maglev train can reach 300 mph with people onboard.

Electrodynamic Suspension (EDS)

Japanese engineers are developing a competing version of maglev trains that use an electrodynamic suspension (EDS) system, which is based on the repelling force of magnets. The key difference between Japanese and German maglev trains is that the Japanese trains use super-cooled, superconducting electromagnets. This kind of electromagnet can conduct electricity even after the power supply has been shut off. In the EMS system, which uses standard electromagnets, the coils only conduct electricity when a power supply is present. By chilling the coils at frigid temperatures, Japan's system saves energy.However, the cryogenic system uses to cool the coils can be expensive.
Another difference between the systems is that the Japanese trains levitate nearly 4 inches (10 cm) above the guideway. One potential drawback in using the EDS system is that maglev trains must roll on rubber tires until they reach a liftoff speed of about 62 mph (100 kph). Japanese engineers say the wheels are an advantage if a power failure caused a shutdown of the system. Germany's Transrapid train is equipped with an emergency battery power supply. Also, passengers with pacemakers would have to be shielded from the magnetic fields generated by the superconducting electromagnets.
The Inductrack is a newer type of EDS that uses permanent room-temperature magnets to produce the magnetic fields instead of powered electromagnets or cooled superconducting magnets. Inductrack uses a power source to accelerate the train only until begins to levitate. If the power fails, the train can slow down gradually and stop on its auxillary wheels.
The track is actually an array of electrically-shorted circuits containing insulated wire. In one design, these circuits are aligned like rungs in a ladder. As the train moves, a magnetic field the repels the magnets, causing the train to levitate.
There are two Inductrack designs: Inductrack I and Inductrack II. Inductrack I is designed for high speeds, while Inductrack II is suited for slow speeds. Inductrack trains could levitate higher with greater stability. As long as it's moving a few miles per hour, an Inductrack train will levitate nearly an inch (2.54 cm) above the track. A greater gap above the track means that the train would not require complex sensing systems to maintain stability.
Permanent magnets had not been used before because scientists thought that they would not create enough levitating force. The Inductrack design bypasses this problem by arranging the magnets in a Halbach array. The magnets are configured so that the intensity of the magnetic field concentrates above the array instead of below it. They are made from a newer material comprising a neodymium-iron-boron alloy, which generates a higher magnetic field. The Inductrack II design incorporates two Halbach arrays to generate a stronger magnetic field at lower speeds.
Dr. Richard Post at the Livermore National Laboratory in California came up with this concept in response to safety and cost concerns. The prototype tests caught the attention of NASA, which awarded a contract to Dr. Post and his team to explore the possibility of using the Inductrack system to launch satellites into orbit.

Maglev Technology In Use

While maglev transportation was first proposed more than a century ago, the first commercial maglev train made its test debut in Shanghai, China, in 2002 (click here to learn more), using the train developed by German company Transrapid International. The same line made its first open-to-the-public commercial run about a year later in December of 2003. The Shanghai Transrapid line currently runs to and from the Longyang Road station at the city's center and Pudong airport. Traveling at an average speed of 267 mph (430 kmh), the 19 mile (30 km) journey takes less than 10 minutes on the maglev train as opposed to an hour-long taxi ride. China is building an extension of the Shanghai line that will run 99 miles (160 km) to Hangzhou. Construction is scheduled to begin in fall 2006 and should be completed by the 2010 Shanghai Expo. This line will be the first Maglev rail line to run between two cities.
Several other countries have plans to build their own maglev trains, but the Shanghai airport line remains the only commercial maglev line. U.S. cities from Los Angeles to Pittsburgh have had maglev line plans in the works, but the expense of building a maglev transportation system has been prohibitive. The administration at Old Dominion University in Virginia had hoped to have a super shuttle zipping students back and forth across campus starting back in the fall semester of 2002, but the train remains motionless while research continues. The American Maglev Company is building a prototype using similar technology in Georgia that it plans to finish by fall 2006.

Modern Flying Cars

                        The M200X, the predecessor of the Skycar, flew for the first time in 1989 to a height of 50 feet.
Photo courtesy Moller International

                     When George Jetson first flew across American TV screens in his flying car-like vehicle in 1962, many of us began wondering when we could buy our own Supersonic Suburbanite or Spacion Wagon. Amazingly, that day may be around the corner. After a century of unfulfilled promises, flying cars may fill the skies in the next few decades. There are still some obstacles to overcome, including receiving approval from the FAA, but the cars are close to being finished.
There is no lack of engineers taking on the challenge to design a new breed of flying cars. While sleeker, more advanced cars have been developed in the last decade, no one has come close to opening up a flying car dealership. Here are a few of the individuals attempting to deliver a flying car:
  • Paul Moller has spent 40 years and millions of dollars developing his Skycar. He is now very close to developing the first mass-marketed flying car. In 1965, he demonstrated his first attempt, the XM-2, which hovered off the ground but didn't go anywhere. In 1989, Moller unveiled the M200X, which has now flown 200 flights and can go as high as 50 feet (15.24 meters).
  • MACRO Industries in Huntsville, Ala., is developing a flying car that it's calling the SkyRider X2R. This aero car will be able to take off and land vertically. SkyRider incorporates the interior design of a 2-seat sports car with the mobility of a helicopter or airplane. The company said it is also developing 5 and 7-seat models of the SkyRider, and it should fit in most two-car garages. The navigation system will be controlled almost entirely by GPS satellites and cellular services.
  • In Israel, Dr. Rafi Yoeli of Urban Aeronautics is testing the CityHawk, a prototype of a fly-by-wire car. He's also working on a project centered around the X-Hawk, a rotorless Verticle-Take-Off and Landing vehicle (VTOL).
  • In 1990, Kenneth Wernicke formed Sky Technologies to develop a small-winged flying car. His Aircar has flown at 200 to 400 mph (322 to 644 kph) and driven at 65 mph (105 kph). It's also small enough to fit into an average parking space.
  • Recently, Branko Sarh, a senior engineer at McDonnell Douglas Aerospace, has attempted to develop a flying car, called the Sokol A400, or Advanced Flying Automobile. Sarh designed a 4-passenger vehicle that would pop out telescoping wings at the push of a button.

The Skycar will be operated completely by computer and guided by GPS satellites.
Photo courtesy Moller International
Moller's latest design, the Skycar M400, is designed to take off and land vertically, like a Harrier Jet, in small spaces. It can reach speeds of 400 mph (644 kph), but will cruise at around 350 mph (563 kph), and it has a range of 900 miles (1449 km). Gasoline, diesel, alcohol, kerosene and propane can be used to fuel the Skycar, and its fuel mileage will be comparable to that of a medium-sized car, getting 20 miles (32.2 km) to the gallon. The initial cost of a Skycar will be about $1 million, but once it begins to be mass produced that price could come down to as low as $60,000.
The four-seat Skycar is powered by eight rotary engines that are housed inside four metal housings, called nacelles, on the side of the vehicle. There are two engines in each nacelle so that if one of the engines in one of the nacelle fails, the other engine can sustain flight. The engines lift the craft with 720 horsepower, and then thrust the craft forward. The Wankel engine replaces pistons of a conventional engine with a single triangular rotor spinning inside an oval-shaped chamber, which creates compression and expansion as the rotor turns. There are three combustion chambers in the Wankel, with a crankshaft between them.
To make the Skycar safe and available to the general public, it will be completely controlled by computers using Global Positioning System (GPS) satellites, which Moller calls a fly-by-wire system. In case of an accident, the vehicle will release a parachute and airbags, internally and externally, to cushion the impact of the crash.
MACRO Industries' SkyRider X2R will also use this fly-by-wire system to safely transport passengers to their desired destinations. Drivers will simply get in, turn on the power and enter the address or phone number of their destination. SkyRider will do the rest. MACRO said that the system will be almost fully automatic, but may allow some manual control. Commands will be entered just by telling the car what you want it to do.
According to their Web site, MACRO is shooting to have a working vehicle produced sometime in 2006. The company is planning to power the vehicle with an enhanced automobile engine to drive four-ducted fans. The unique feature of the SkyRider will be the company's patented rotary cartridge valve, which is expected to increase fuel efficiency and reduce emissions.
The CityHawk is similar to the Skycar and SkyRider in that it also takes off and lands vertically. However, there are some key differences. The CityHawk will be powered by fans that are driven by four internal combustion engines. Much like in the Skycar, this redundancy of engines will allow the vehicle to land even if one of the engines is lost. The CityHawk is about the size of a Chevy Surburban, and will have cruising speeds of 90 to 100 miles per hour (145 to 161 kph). CityHawk developers say that it could be used as an air taxi, for news gathering and for traffic control.
The mass availability of flying cars could be very exciting or very scary, depending on how you look at it. If proper safeguards are put in place, they could be the answer to our ever-worsening traffic jams. Flying cars that can travel at hundreds of miles per hour would not only cut that rush hour commute to a few minutes, but it would allow us to live hundreds of miles farther from work and still make it to the office faster than by road-bound cars today.

Wednesday 16 May 2012

World's Most Expensive Cars:

1. Bugatti Veyron Super Sports:
 $2,400,000. This is by far the most expensive street legal car available on the market today (the base Veyron costs $1,700,000). It is the fastest accelerating car reaching 0-60 in 2.5 seconds. It is also the fastest street legal car when tested again on July 10, 2010 with the 2010 Super Sport Version reaching a top speed of 267 mph. When competing against the Bugatti Veyron, you better be prepared!


Bugatti Veyron: Most Expensive Car in The World
2. Aston Martin One-77  
$1,850,000. The name "One-77" says it all: beauty and power in One, limited to 77 units. With 750 hp, it is able to travel from 0 to 60 mph in 3.4 seconds and reaching a maximum speed of 220 mph.
Very expensive and sexy car
2. Pagani Zonda Clinque Roadster 
$1,850,000. One of the most exotic cars out there is also one of the most expensive. It can go from 0-60 in 3.4 seconds with a top speed of 217 mph.
We have another tie for 3rd place:
3. Lamborghini Reventon 
$1,600,000. The most powerful and the most expensive Lamborghini ever built is the third on the list. It takes 3.3 seconds to reach 60 mph and it has a top speed of 211 mph. Its rarity (limited to 20) and slick design are the reasons why it is so expensive and costly to own.
Lamborghini Reventon side view

3. Koenigsegg Agera R
 $1,600,000. The Agera R can burn 0-60 in 2.8 seconds, reaching a maximum speed of 260 mph. It has the parts to reach 270 mph, but the supercar is electronically capped at 235 mph. With the completion of certain paperwork, the company will unlock the speed limit for one occasion.
4. Maybach Landaulet  
$1,380,000. The Landaulet is the most expensive sedan on the market and it can reach from 0-60 in 5.2 seconds. Probably the most luxurious car ever made with a convertible roof that can open fully at the rear. This car is made especially for those CEOs and Executives who have their own personal driver.

5. Zenvo ST1  
$1,225,000. Able to reach 60 mph in 2.9 seconds and a top speed of 233 mph. The Zenvo ST1 is from a new Danish supercar company that will compete to be the best in speed and style. The ST1 is limited to 15 units and the company even promised "flying doctors" to keep your car running.

6. McLaren F1 
$970,000. In 1994, the McLaren F1 was the fastest and most expensive car. Even though it was built more than 15 years ago, it has an unbelievable  top speed of 240 mph and reaching 60 mph in 3.2 seconds. Even today, the McLaren F1 is still top on the list and outperforms many other supercars.
McLaren F1 Orange with doors open
7. Ferrari Enzo 
$670,000. The most popular supercar ever built. The Enzo has a top speed of 217 mph and reaching 60 mph in 3.4 seconds. Only 400 units were produced and it is currently being sold for over $1,000,000 at auctions.
Ferrari Enzo track run front view
8. Pagani Zonda C12 F 
$667,321. Produced by a small independent company in Italy, the Pagani Zonda C12 F is the 8th most expensive car in the world. It promises to delivery a top speed of 215 mph+ and it can reach 0-60 in 3.5 seconds.
Pagani Zonda C12 F: 2nd Most Expensive Car in the World
9. SSC Ultimate Aero 
$654,400. Don't let the price tag fool you, this American made car is actually the 3rd fastest street legal car in the world with a top speed of 257 mph+ and reaching 0-60 in 2.7 seconds. This baby cost less than half as much as the Bugatti Veyron, yet has enough power to compete against the most expensive car. It is estimated that only 25 of this exact model will ever be produced.
SSC Ultimate Aero 3rd most expensive car in the world
10. Ascari A10  
$650,000. This badboy can reach a tested top speed of 215 mph, zooming 0-60 in 2.8 seconds. The British car company plans to assemple 50 of these supercars in their factory in Banbury, England.

AMD gets Guinness World Record for fastest CPU with overclocked octa-core FX processorAMD gets Guinness World Record for fastest CPU with overclocked octa-core FX processor

Speed. It's of paramount importance in evaluating any computer system, and the engine that gives your PC its get up and go is its CPU. The folks at AMD wanted to show off just how awesome (and fast) their new Bulldozer-based FX chips can be, and set a Guinness World Record for the "Highest Frequency of a Computer Processor" while they were at it. To get the record, a team of "elite overclocking specialists" cranked up the juice on an 8-core desktop CPU until hitting a speed of 8.429GHz -- handily surpassing the previous mark of 8.308GHz. So, AMD's got the fastest silicon in the west and it's chipping away at Intel's processor predominance. What say you, Chipzilla?