Рис. 69

Tower И

significant margin. Towers are distinguishedАfrom masts by their lack of guywires.

A tower is a tall structure, usuallyДtaller than it is wide, often by a

Towers are generally builtбto take advantage of their height, and can stand alone on the ground, or as part of a larger structure or device such as a fortified building or as an integralиpart of a bridge.

A modern type of tower, the skyscraper, uses less ground space as a ratio of total building interiorСsquare footage. Skyscrapers are often not classified as towers, although most have the same design and structure of towers. In the United Kingdom, tall domestic buildings are referred to as tower blocks. In the United States, the original World Trade Center had the nickname the Twin Towers, a name shared with the Petronas Twin Towers in Kuala Lumpur. A tower has very deep foundations.

The tower throughout history has provided its users with an advantage in surveying defensive positions and obtaining a better view of the surrounding areas, including battlefields. They were constructed on defensive walls, or rolled near a target (see siege tower). Today, strategic-use towers are still used at prisons, military camps, and defensive perimeters.

By using gravity to move objects or substances downward, a tower can be used to store items or liquids like a storage silo or a water tower, or aim an object into the earth such as a drilling tower. Ski-jump ramps use the same idea, and in the absence of a natural mountain slope or hill, can be human-made.

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In history, simple towers like lighthouses, bell towers, clock towers, signal towers and minarets were used to communicate information over greater distances. In more recent years, radio masts and cell phone towers facilitate communication by expanding the range of the transmitter. The CN Tower in Toronto, Canada was built as a communications tower, with the capability to act as both a transmitter and repeater. Its design also incorporated features to make it a tourist attraction, including the world's highest observation deck at 147 storeys.

Towers can also be used to support bridges, and can reach heights that rival some of the tallest buildings above-water. Their use is most prevalent in suspension bridges and cable-stayed bridges. The use of the pylon, a simple tower structure, has also helped to build railroad bridges, mass-transit systems,

and harbors.						И
Control towers are used to give visibility to help direct aviation traffic
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	Рис. 70

Рис. 72

Рис. 73

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Рис. 74					И	Рис. 75
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Рис. 76

Рис. 78

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Museum

A museum is an institution that cares for (conserves) a collection of artifacts and other objects of scientific, artistic, cultural, or historical importance and makes them available for public viewing through exhibits that may be permanent or temporary. Most large museums are located in major cities throughout the world and more local ones exist in smaller cities, towns and even the countryside. Museums have varying aims, ranging from serving researchers and specialists to serving the general public. The continuing acceleration in the digitization of information, combined with the increasing capacity of digital information storage, is causing the traditional model of museums (i.e. as static “collections of collections” of three-dimensional specimens and artifacts) to expand to include virtual exhibits and highresolution images of their collections for perusal, study, and exploration from any place with Internet. The city with the largest number of museums is Mexico

City with over 128 museums. According to The World Museum Community,
there are more than 55,000 museums in 202 countries (рис. 79–83).
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Рис. 79

Рис. 80

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Рис. 81				Д		Рис. 82
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Рис. 83

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