Web Proxy

Web proxy

Proxies that hub on WWW traffic are called web proxies. Many web proxies try to block offensive web content. Other web proxies reformat web pages for an exact purpose or audience (e.g., cell phones and PDAs or persons with disabilities). Network operators can also set up proxies to intercept computer viruses and other hostile content served from remote web pages.

Many organizations — including schools, corporations, and countries — use proxy servers to implement acceptable network use policies or to provide security, anti-malware and/or caching services. A traditional web proxy is not translucent to the client application, which must be configured to use the proxy (manually or with a configuration script). In some cases, where substitute means of connection to the Internet are available ,the user may be able to avoid policy control by simply resetting the client configuration and bypassing the proxy. Furthermore administration of browser configuration can be a load for network administrators.

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Pollarding

Pollarding is a woodland management method of hopeful lateral branches by cutting off a tree stem or minor branches two metres or so above ground level. The tree is given a year to regrow, after the first cutting, but once begun, pollarding requires annual maintenance by pruning. This will ultimately result in somewhat expanded (or swollen) nodes topping the tree trunk with multiple new side and top shoots growing from it.

A tree that has been pollarded is known as a pollard.A tree which has not been pollarded is called a maiden or maiden tree; which also refers to the fact that pollarding is usually first undertaken when the tree is quite young. Pollarding older trees typically result in the death of the tree. Pollarding is sometimes abused in attempts to curb the growth of older or taller trees. However, when performed properly it is useful in the practice of arboriculture for tree management.

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Batteries

Electronic watches require electricity as a power source. Some mechanical movements and hybrid electronic-mechanical actions also require electricity. Usually the electricity is provided by a replaceable battery.

The first use of electrical power in watches was as replacement for the mainspring, in order to remove the need for winding. The first electrically-powered watch, the Hamilton Electric 500, was released in 1957 by the Hamilton Watch Company of Lancaster, Pennsylvania. Batteries for watches are specially designed for their purpose. They are very small and provide tiny amounts of power incessantly for very long periods. In most cases, replacing the battery requires a trip to a watch-repair shop or watch dealer; this is especially true for watches that are designed to be water-resistant, as special tools and procedures are required to ensure that the watch remains water-resistant after battery replacement. Silver-oxide and lithium batteries are popular today; mercury batteries, formerly quite common, are no longer used, for ecological reasons. Cheap batteries may be alkaline, of the same size as silver-oxide but providing shorter life.

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Information Technology

Information technology (IT), is the study, design, development, implementation, support or administration of computer-based information systems, particularly software applications and computer hardware.In short, IT deals with the use of electronic computers and computer software to transfer, store, protect, process, transmit and get back information, securely.

In this definition, the term "information" can frequently be replaced by "data" without loss of meaning. Recently it has become popular to widen the term to explicitly consist of the field of electronic communication so that people tend to use the abbreviation ICT (Information and Communication Technology). Strictly speaking, this name contains some redundancy.

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RISC(Reduced Instruction Set Computer)

In the mid-1980s to early-1990s, a crop of new high-performance RISC microprocessors appeared, which were initially used in special purpose machines and UNIX workstations, but have since become almost universal in all roles except the Intel-standard desktop.The first commercial design was released by MIPS Technologies, the 32-bit R2000. The R3000 made the design truly practical, and the R4000 introduced the world's first 64-bit design. Opposing projects would result in the IBM POWER and Sun SPARC systems, respectively. Soon every major vendor was releasing a RISC design, including the AT&T CRISP, AMD 29000, Intel i860 and Intel i960, Motorola 88000, DEC Alpha and the HP-PA

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Super Scalar

A superscalar CPU architecture implements a form of parallelism called Instruction-level parallelism within a solitary processor. It thereby allows faster CPU throughput than would otherwise be possible at the same clock rate. A superscalar architecture executes more than one instruction during a single pipeline stage by pre-fetching several instructions and at the same time dispatching them to redundant functional units on the processor.

History

Seymour Cray's CDC 6600 from 1965 is often mentioned as the first superscalar plan. The Intel i960CA and the AMD 29000-series 29050 microprocessors were the first commercial single-chip superscalar microprocessors. RISC CPUs like these brought the superscalar idea to micro computers because the RISC design results in a simple core, allowing straightforward instruction send off and the inclusion of multiple functional units on a single CPU in the inhibited design rules of the time. This was the reason that RISC designs were faster than CISC designs through the 1980s and into the 1990s.

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Solar System

Solar System consists of the Sun and the other space objects gravitationally bound to it: the eight planets, their 162 known moonsthree currently recognized dwarf planets (including Pluto) and their four known moons, and billions of small bodies. This last group includes asteroids, Kuiper belt objects, comets, meteoroids and interplanetary dust.

In wide terms, the charted regions of the Solar System consist of the Sun, four terrestrial inner planets, an asteroid belt composed of small rocky bodies, four gas giant outer planets, and a second belt, called the Kuiper belt, collected of icy objects. Beyond the Kuiper belt lies the scattered disc, the heliopause, and eventually the hypothetical Oort cloud.

In sort of their distances from the Sun, the planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Six of the eight planets are in turn orbited by natural satellites, usually termed "moons" after Earth's Moon, and each of the outer planets is encircled by planetary rings of dust and other particles. All the planets apart from Earth are named after gods and goddesses from Greco-Roman mythology. The three dwarf planets are Pluto, the largest known Kuiper belt object; Ceres, the largest object in the asteroid belt; and Eris, which lies in the scattered disc.

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Water pollution


Water pollution is a large set of unfavorable belongings upon water bodies such as lakes, rivers, oceans, and groundwater caused by human activities. Although natural phenomena such as volcanoes, algae blooms, storms, and earthquakes also cause main changes in water quality and the environmental status of water, these are not deemed to be pollution. Water pollution has many causes and characteristics. Increases in nutrient loading may lead to eutrophication. Organic wastes such as sewage inflict high oxygen demands on the getting water leading to oxygen depletion with potentially severe impacts on the whole eco-system. Industries discharge a variety of pollutants in their wastewater including grave metals, organic toxins, oils, nutrients, and solids. Discharges can also have thermal effects, especially those from power stations, and these too reduce the available oxygen. Silt-bearing runoff from many activities together with construction sites, deforestation and agriculture can reduce the penetration of sunlight through the water column, restricting photosynthesis and causing blanketing of the lake or river bed, in turn damaging ecological systems.

Pollutants in water consist of a wide spectrum of chemicals, pathogens, and physical chemistry or sensory changes.A lot of the chemical substances are toxic. Pathogens can apparently produce waterborne diseases in either human or animal hosts. Alteration of water's physical chemistry include acidity, conductivity, temperature, and eutrophication. Eutrophication is the fertilisation of surface water by nutrients that were previously scarce. Even many of the municipal water supplies in developed countries can present health risks.

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Nano Technology


Nanotechnology is a pasture of applied science and technology covering a wide range of topics. The main unifying premise is the control of matter on a scale smaller than 1 micrometer, normally between 1-100 nanometers, as well as the manufacture of devices on this same length scale. It is a highly multidisciplinary field, drawing from fields such as colloidal science, device physics, and supramolecular chemistry. Much hypothesis exists as to what new science and technology might result from these lines of research. Some view nanotechnology as a marketing term that describes pre-existing lines of research applied to the sub-micron size scale.

In spite of the apparent ease of this definition, nanotechnology actually encompasses diverse lines of inquiry. Nanotechnology cuts across many disciplines, together with colloidal science, chemistry, applied physics, materials science, and even mechanical and electrical engineering. It could variously be seen as an extension of existing sciences into the nanoscale, or as a recasting of existing sciences using a newer, more recent term. Two major approaches are used in nanotechnology: one is a "bottom-up" approach where materials and devices are built from molecular components which gather themselves chemically using principles of molecular gratitude; the other being a "top-down" approach where nano-objects are constructed from larger entities without atomic-level control.

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Transportation

Transportation is the movement of people and goods from one place to another. The term is derived from the portare ("to carry") and Latin trans ("across") . Industries which have the business of providing equipment, actual transport, transport of people or goods and services used in transport of goods or people make up a huge broad and important segment of most national economies, and are collectively referred to as transport industries.
The field of transport has several aspects: loosely they can be divided into a triad of infrastructure, vehicles, and operations. Infrastructure includes the transport networks (roads, railways, airways, waterways, canals, pipelines, etc.) that are used, as well as the nodes or terminals (such as airports, railway stations, bus stations and seaports). The vehicles generally traverse on the networks, such as automobiles, bicycles, buses, trains, aircrafts

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