Wednesday, March 28, 2007
History of sport
There are artifacts and structures that propose that the Chinese engaged in sporting activities as early as 4000 BC.Gymnastics appears to have been a well-liked sport in China's ancient past. Monuments to the Pharaohs indicate that a number of sports, with swimming and fishing, were well-developed and regulated several thousands of years ago in ancient Egypt.Other Egyptian sports incorporated javelin throwing, high jump, and wrestling. Ancient Persian sports such as the conventional Iranian martial art of Zourkhaneh had a close connection to the warfare skills.Among other sports that originate in Persia are polo and jousting.
Friday, March 23, 2007
Telegraphy
Telegraphy (from the Greek words tele = far and graphein = write) is the long-distance transmission of written messages without physical transport of letters, initially over wire. Radiotelegraphy or wireless telegraphy transmits messages using radio. This definition includes recent forms of data transmission such as fax, email, and computer networks in general. (A telegraph is a machine for transmitting and receiving messages over long distances, i.e. for telegraphy. The word telegraph alone generally refers to an electrical telegraph.) Wireless telegraphy is also well-known as CW, for continuous wave (a carrier modulated by on-off keying, as opposed to the earlier radio technique using a spark gap).
Telegraphy messages sent by telegraph operators using Morse code were known as telegrams or cablegrams, frequently shortened to a cable or a wire message. Later, telegrams sent by the Telex network, a switched network of teleprinters similar to the telephone network, were identified as telex messages. Before long distance telephone services were willingly available or affordable, telegram services were very popular. Telegrams were frequently used to confirm business dealings and, unlike e-mail, telegrams were usually used to create binding legal documents for business dealings.
Before fax machines came into general use, wire picture or wire photo was a newspaper picture that was sent from a remote location by a facsimile telegraph. This is why many fax machines have a photo option even today.
Optical telegraphs and smoke signals
The first telegraphs were optical telegraphs, with the use of smoke signals and beacons. These have existed since ancient times. A semaphore network invented by Claude Chappe operated in France from 1792 through 1846. It helped Napoleon enough that it was widely imitated in Europe and the U.S. The last commercial semaphore link left operation in 1880.
Semaphores were able to communicate information more precisely than smoke signals and beacons and consumed no fuel. Messages could be sent at much greater speed than post riders and could serve entire regions. However, like beacons and smoke signals, they were dependent on good weather to work. They required operators and towers every 30 km (20 mi), and only send about two words per minute. This was useful to governments, but too expensive for most commercial uses other than commodity price information. Electric telegraphs were to reduce the cost of sending a message thirty-fold compared to semaphore.
Telegraphy messages sent by telegraph operators using Morse code were known as telegrams or cablegrams, frequently shortened to a cable or a wire message. Later, telegrams sent by the Telex network, a switched network of teleprinters similar to the telephone network, were identified as telex messages. Before long distance telephone services were willingly available or affordable, telegram services were very popular. Telegrams were frequently used to confirm business dealings and, unlike e-mail, telegrams were usually used to create binding legal documents for business dealings.
Before fax machines came into general use, wire picture or wire photo was a newspaper picture that was sent from a remote location by a facsimile telegraph. This is why many fax machines have a photo option even today.
Optical telegraphs and smoke signals
The first telegraphs were optical telegraphs, with the use of smoke signals and beacons. These have existed since ancient times. A semaphore network invented by Claude Chappe operated in France from 1792 through 1846. It helped Napoleon enough that it was widely imitated in Europe and the U.S. The last commercial semaphore link left operation in 1880.
Semaphores were able to communicate information more precisely than smoke signals and beacons and consumed no fuel. Messages could be sent at much greater speed than post riders and could serve entire regions. However, like beacons and smoke signals, they were dependent on good weather to work. They required operators and towers every 30 km (20 mi), and only send about two words per minute. This was useful to governments, but too expensive for most commercial uses other than commodity price information. Electric telegraphs were to reduce the cost of sending a message thirty-fold compared to semaphore.
Monday, March 19, 2007
Camera
A camera is a device used to take pictures (usually photographs), also singly or in sequence, with or without sound, such as with video cameras. The name is derived from camera obscura, Latin for "dark chamber", an early mechanism for projecting images in which an entire room functioned much as the internal workings of a modern photographic camera, except there was no way at this time to record the image short of physically tracing it. Cameras may work with the visual spectrum or other portions of the electromagnetic spectrum.
Tuesday, March 13, 2007
Fog
Fog is a cloud in contact with the ground. Fog differs from other clouds only in that fog touches the surface of the Earth. The similar cloud that is not fog on lower ground may be fog where it contacts higher ground such as hilltops or mountain ridges. Fog is different from mist only in its density. Fog is defined as cloud which reduces visibility to less than 1 km, whereas mist is that which reduces visibility to less than 2 km.
The foggiest place in the world is the Grand Banks off the island of Newfoundland, Canada. Fog is common here as the Grand Banks is the meeting place of the cold Labrador Current from the north and the much warmer Gulf Stream from the south. The foggiest land areas in the world are Point Reyes, California and Argentia, Newfoundland, both with over 200 foggy days a year.
The foggiest place in the world is the Grand Banks off the island of Newfoundland, Canada. Fog is common here as the Grand Banks is the meeting place of the cold Labrador Current from the north and the much warmer Gulf Stream from the south. The foggiest land areas in the world are Point Reyes, California and Argentia, Newfoundland, both with over 200 foggy days a year.
Thursday, March 08, 2007
Photographyv
Photography is the method of making pictures by means of capturing light on a light-sensitive medium, such as a sensor or film. Light patterns reflected or emitted from objects are recorded onto a sensitive medium or storage chip through a timed exposure. The process is done through mechanical, chemical or digital devices well-known as cameras.
The word comes from the Greek words phos ("light"), and graphis ("stylus", "paintbrush") or graphĂȘ, together meaning "drawing with light" or "representation by means of lines" or "drawing." usually the product of photography has been called a photograph. The term photo is an abbreviation; many people also call them pictures. In digital photography, the term image has begun to replace photograph.
The word comes from the Greek words phos ("light"), and graphis ("stylus", "paintbrush") or graphĂȘ, together meaning "drawing with light" or "representation by means of lines" or "drawing." usually the product of photography has been called a photograph. The term photo is an abbreviation; many people also call them pictures. In digital photography, the term image has begun to replace photograph.
Sunday, March 04, 2007
Science and technology in Japan
Japan is a foremost nation in the fields of scientific research, technology, machinery and medical research with the world's third biggest budget for research and development at US$130 billion, and over 677,000 researchers.
Some of Japan's more important technological contributions are found in the fields of electronics, machinery, industrial robotics, optics, chemicals, semiconductors and metals. Japan leads the world in robotics, possessing more than half (402,200 of 742,500) of the world's industrial robots used for manufacturing.It also produced QRIO, ASIMO, and Aibo. Japan is also home to six of the world's 15 biggest automobile manufacturers and seven of the world 20 largest semiconductor sales leaders.
Japan has also made headway into aerospace research and space exploration. The Japan Aerospace Exploration Agency (JAXA) conducts space and planetary research, aviation research, and growth of rockets and satellites. It also built the Japanese Experiment Module, which is slated to be launched and added to the International Space Station during Space Shuttle assembly flights in 2007 and 2008.
Some of Japan's more important technological contributions are found in the fields of electronics, machinery, industrial robotics, optics, chemicals, semiconductors and metals. Japan leads the world in robotics, possessing more than half (402,200 of 742,500) of the world's industrial robots used for manufacturing.It also produced QRIO, ASIMO, and Aibo. Japan is also home to six of the world's 15 biggest automobile manufacturers and seven of the world 20 largest semiconductor sales leaders.
Japan has also made headway into aerospace research and space exploration. The Japan Aerospace Exploration Agency (JAXA) conducts space and planetary research, aviation research, and growth of rockets and satellites. It also built the Japanese Experiment Module, which is slated to be launched and added to the International Space Station during Space Shuttle assembly flights in 2007 and 2008.
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