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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