Wednesday, February 25, 2009

supercomputer

A supercomputer is a computer that leads the world in terms of processing capacity and speed of calculation. New York World newspaper in 1929 refers to a large custom-built tabulators IBM made for Columbia University first used the term “Super Computing”. Super Computers introduced in the year 1960s and were designed by Seymour Cray at Control Data Corporation (CDC), and led the market into the 1970s. The term supercomputer itself is rather fluid, and today's supercomputer tends to become tomorrow's also-ran.

Technologies developed for Supercomputers include:
Vector processing
Liquid cooling Non-Uniform Memory Access (NUMA)
Striped disks
Parallel file systems

Supercomputers traditionally gained their speed over conventional computers through the use of innovative designs that allow them to perform many tasks in parallel, as well as complex detail engineering. They tend to be specialized for certain types of computation, usually numerical calculations, and perform poorly at more general computing tasks. Their memory hierarchy is very carefully designed to ensure the processor; much of the performance difference between slower computers and supercomputers is due to the memory hierarchy. Their I/O systems tend to be designed to support high bandwidth, with latency less of an issue, because supercomputers are not used for transaction processing.

Supercomputers are used for highly calculation-intensive tasks such as weather forecasting, climate research (including research into global warming), molecular modeling (computing the structures and properties of chemical compounds, biological macromolecules, polymers, and crystals), physical simulations (such as simulation of airplanes in wind tunnels, simulation of the detonation of nuclear weapons, and research into nuclear fusion), cryptanalysis, and the like. Major universities, military agencies and scientific research laboratories are heavy users.

Thursday, January 22, 2009

Electrical resistance

Electrical resistance is a compute of the degree to which an object opposes an electric current through it. The SI unit of electrical resistance is the ohm. Its reciprocal quantity is electrical conductance calculated in siemens. Electrical resistance shares some conceptual parallels with the mechanical notion of friction.

The resistance of an object determines the amount of current through the object for a known voltage across the object I=V/R, where R is the resistance of the object, measured in ohms, equivalent to J•s/C2, V is the voltage across the object, measured in volts, I is the current through the object, measured in amperes. In metals, the Fermi level lies in the conduction band giving rise to free transfer electrons. However, in semiconductors the position of the fermi level is within the band gap, closely half way between the conduction band minimum and valence band maximum for intrinsic semiconductors.

Thursday, December 11, 2008

Education

Education encompasses teaching and learning specific skills, and also something less tangible but more profound: the imparting of knowledge, positive judgment and well-developed wisdom. Education has as one of its fundamental aspects the imparting of culture from generation to generation. Education mean 'to draw out', are facilitating realization of self-potential and latent talents of an individual. It is an application of pedagogy, a body of theoretical and applied research relating to teaching and learning and draws on many disciplines such as psychology, philosophy, computer science, linguistics, neuroscience, sociology and anthropology.

The education of an individual human begins at birth and continues throughout life. For some, the struggles and triumphs of daily life provide far more instruction than doe’s formal schooling. Family members may have a profound educational effect often more profound than they realize though family teaching may function very informally.

Friday, October 10, 2008

Gear

A gear is a wheel with teeth around its circumference, the purpose of the teeth being to mesh with similar teeth on another mechanical device possibly another gear wheel so that force can be transmitted between the two strategies in a direction tangential to their surfaces. A non-toothed wheel can transmit some tangential force but will slip if the force is large; teeth put off slippage and permit the transmission of large forces.

A gear can mesh with any device having teeth friendly with the gear's teeth. Such devices include racks and other non-rotating policy; however, the most common condition is for a gear to be in mesh with another gear. In this case revolution of one of the gears necessarily causes the other gear to rotate. In this way, rotational motion can be transferred from one position to another. While gears are sometimes used simply for this reason to transmit rotation to another shaft perhaps their most significant feature is that, if the gears are of asymmetrical sizes, a mechanical advantage is also achieved, so that the rotational speed, and torque, of the second gear are dissimilar from that of the first. In this way, gears provide a means of increasing or decreasing a turning speed, or a torque.

Thursday, September 11, 2008

Indicator

Dial indicators are instruments used to correctly measure a small distance. They may also be known as a Dial gauge, Dial Test Indicator, or as a clock. They are named so because the measurement results are displayed in a overstated way by means of a dial. They may be used to check the dissimilarity in tolerance during the check process of a machined part, measure the deflection of a beam or ring under laboratory conditions, as well as many other situations where a small measurement needs to be registered or indicated.

An economic indicator is a statistic concerning the economy. The lighting system of a motor vehicle consists of lighting and signaling procedure mounted or integrated to the front, sides and rear of the vehicle. The purpose of this system is to present illumination for the driver to operate the vehicle safely after dark, to increase the visibility of the vehicle, and to display information about the vehicle's presence, position, size, direction of travel, and driver's intentions concerning direction and speed of travel.

Tuesday, July 08, 2008

Software

Software, consisting of programs, enables a computer to perform specific tasks, as opposed to its physical components which can only do the responsibilities they are mechanically designed for. The term includes application software such as word processors which perform helpful tasks for users, system software such as operating systems, which interface with hardware to run the necessary services for user-interfaces and applications, and middleware which controls and co-ordinates distributed system.

Computer software has to be loaded into the computer's storage space (memory or RAM). Once the software is loaded, the computer is able to implement the software. Computers control by executing the computer program. This involves passing instructions from the application software, through the system software, to the hardware which finally receives the instruction as machine code. Each instruction causes the computer to carry out an operation moving data, transport out a computation, or altering the control flow of instructions.

Wednesday, May 14, 2008

Animals

Animals are a major group of generally motile, multicultural organisms that feed by consuming material from other living things. Their body plan becomes fixed as they develop, usually early on in their development as embryos, although some undergo a process of metamorphosis later on.

The word "animal" comes from the Latin word animal, of which animal is the plural, and is derived from anima, meaning vital breath or soul. In everyday colloquial usage, the word usually refers to non-human animals. The biological definition of the word refers to all members of the Kingdom Animalia. Therefore, when the word animal is used in a biological context, humans are included.