Computer hardware Essays - Computer Hardware, Electronics

Computer hardware Essays - Computer Hardware, Electronics Computer hardware Computer hardware (usually simply called hardware when a computing context is implicit) is the collection of physical elements that constitutes a computer system. Computer hardware is the physical parts or components of a computer, such as the monitor, mouse,keyboard, computer data storage, hard disk drive (HDD), graphic cards, sound cards, memory, motherboard, and so on, all of which are physical objects that are tangible.[1] In contrast, software is instructions that can be stored and run by hardware. Software is any set of machine-readable instructions that directs a computer's processor to perform specific operations. A combination of hardware and software forms a usable computing system. Von Neumann architecture. Von Neumann architecture scheme. The template for all modern computers is the Von Neumann architecture, detailed in a 1945 paper by Hungarian mathematician John von Neumann. This describes a design architecture for an electronic digital computer with subdivisions of a processing unit consisting of anarithmetic logic unit and processor registers, a control unit containing an instruction register and program counter, a memory to store both data and instructions, external mass storage, and input and output mechanisms.[3] The meaning of the term has evolved to mean astored-program computer in which an instruction fetch and a data operation cannot occur at the same time because they share a commonbus. This is referred to as the Von Neumann bottleneck and often limits the performance of the system.[4] Different systems. There are a number of different types of computer system in use today. Personal computer. Hardware of a modern personal computer: 1. Monitor 2.Motherboard 3.CPU 4. RAM 5.Expansion cards6. Power supply 7.Optical disc drive8. Hard disk drive9. Keyboard 10.Mouse. Inside a custom-built computer: power supply at the bottom has its own cooling fan. The personal computer, also known as the PC, is one of the most common types of computer due to its versatility and relatively low price.Laptops are generally very similar, although may use lower-power or reduced size components. Case. The computer case is a plastic or metal enclosure that houses most of the components. Those found on desktop computers are usually small enough to fit under a desk, however in recent years more compact designs have become more common place, such as the all-in-one style designs from Apple, namely the iMac. Though a case can basically be big or small, what matters more is which form factor of motherboard its designed for.[6] Laptops are computers that usually come in a clamshell form factor, again however in more recent years deviations from this form factor have started to emerge such as laptops that have a detachable screen that become tablet computers in their own right. Power supply. A power supply unit (PSU) converts alternating current (AC) electric power to low-voltage DC power for the internal components of the computer. Laptops are capable of running from a built-in battery, normally for a period of hours.[7] Mainboard. The motherboard is the main component of a computer. It is a large rectangular board with integrated circuitry that connects the other parts of the computer including the CPU, the RAM, the disk drives(CD, DVD, hard disk, or any others) as well as any peripherals connected via the ports or the expansion slots. Components directly attached to or part of the motherboard include: The CPU (Central Processing Unit) performs most of the calculations which enable a computer to function, and is sometimes referred to as the "brain" of the computer. It is usually cooled by a heat sink and fan. Most newer CPUs include an on-die Graphics Processing Unit (GPU). The Chipset, which includes the north bridge, mediates communication between the CPU and the other components of the system, including main memory. The Random-Access Memory (RAM) stores the code and data that are being actively accessed by the CPU. The Read-Only Memory (ROM) stores the BIOS that runs when the computer is powered on or otherwise begins execution, a process known as Bootstrapping, or "booting" or "booting up". The BIOS (Basic Input Output System) includes boot firmware and power management firmware. Newer motherboards use Unified Extensible Firmware Interface (UEFI) instead of BIOS. Buses connect the CPU to various internal components and to expand cards for graphics and sound. The CMOS battery is also attached to the motherboard. This battery is the same as a watch battery or a battery for a

Richard Trevithick, Locomotive Pioneer

Richard Trevithick, Locomotive Pioneer Richard Trevithick was a pioneer in early steam engine technology who successfully tested the first steam-powered locomotive, but he ended his life in obscurity. Early Life Trevithick was born in Illogan, Cornwall, in 1771, the son of a Cornish mining family. Dubbed â€Å"The Cornish Giant† for his height- he stood 6’2†, remarkably tall for the time- and for his athletic build, Trevithick was an accomplished wrestler and sportsman, but an unaccomplished scholar. He did, however, have an aptitude for math. And when he was old enough to join his father in the mining business, it was clear that this aptitude extended to the blossoming field of mine engineering, and especially in the use of steam engines. Industrial Revolution Pioneer Trevithick grew up in the crucible of the Industrial Revolution, surrounded by emerging mining technology. His neighbor, William Murdoch, was pioneering new advances in steam-carriage technology.   Steam engines were also used to pump water out of the mines.  Because James Watt already held a number of important steam-engine patents, Trevithick attempted to pioneer steam technology that didn’t rely on Watt’s condenser model.   He succeeded, but not well enough to escape Watt’s lawsuits and personal enmity. And while his use of high-pressure steam represented a new breakthrough, it also drew concerns about its safety. Despite setbacks which gave credibility to those concerns- one accident killed four men- Trevithick continued his work on developing a steam engine that could reliably haul cargo and passengers. He first developed an engine called The Puffing Devil, that traveled not on rails, but on roads. Its limited ability to retain steam prevented its commercial success, however. In 1804, Trevithick successfully tested the first steam-powered locomotive to ride on rails. At seven tons, however, the locomotive- called The Pennydarren- was so heavy it would break its own rails. Drawn to Peru by opportunities there, Trevithick made a fortune in mining- and lost it when he fled that country’s civil war. He returned to his native England, where his early inventions had helped lay the foundation for vast advances in rail locomotive technology. Trevithicks Death and Burial I have been branded with folly and madness for attempting what the world calls impossibilities, and even from the great engineer, the late Mr. James Watt, who said to an eminent scientific character still living, that I deserved hanging for bringing into use the high-pressure engine. This so far has been my reward from the public; but should this be all, I shall be satisfied by the great secret pleasure and laudable pride that I feel in my own breast from having been the instrument of bringing forward and maturing new principles and new arrangements of boundless value to my country. However much I may be straitened in pecunary circumstances, the great honour of being a useful subject can never be taken from me, which to me far exceeds riches.- Richard Trevithick in a letter to Davies Gilbert Denied his pension by the government, Trevithick caromed from one failed financial endeavor to another. Struck by pneumonia, he died penniless and alone in bed. Only at the last minute did some of his colleagues manage to prevent Trevithick’s burial in a pauper’s grave. Instead, he was interred in an unmarked grave at a burial ground in Dartford. The cemetery closed not long after. Years later, a plaque was installed near what is believed to be the site of his grave.