Saturday, June 12, 2010

nasa

The National Aeronautics and Space Administration (NASA, pronounced /ˈnæsə/) is an Executive Branch agency of the United States government, responsible for the nation's civilian space program and aeronautics and aerospace research. Since February 2006 NASA's self-described mission statement is to "pioneer the future in space exploration, scientific discovery and aeronautics research."


NASA was established by the National Aeronautics and Space Act on July 29, 1958, replacing its predecessor, the National Advisory Committee for Aeronautics (NACA). The agency became operational on October 1, 1958  NASA has led U.S. efforts for space exploration ever since, resulting in the Apollo missions to the Moon, the Skylab space station, and later the Space Shuttle. Currently NASA is supporting the International Space Station and is developing a new manned spacecraft called Orion.



NASA science is focused on better understanding Earth through the Earth Observing System  advancing heliophysics through the efforts of the Science Mission Directorate's Heliophysics Research Program exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons  and researching astrophysics topics, such as the Big Bang, through the Great Observatories and associated programs  NASA shares data with various national and international organizations such as from the Greenhouse Gases Observing Satellite.

Thursday, May 27, 2010

Automobile

An automobile, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor. Most definitions of the term specify that automobiles are designed to run primarily on roads, to have seating for one to eight people, to typically have four wheels, and to be constructed principally for the transport of people rather than goods. However, the term automobile is far from precise, because there are many types of vehicles that do similar tasks.

There are approximately 600 million passenger cars worldwide (roughly one car per eleven people). Around the world, there were about 806 million cars and light trucks on the road in 2007; they burn over 1 billion m³ (260 billion US gallons) of petrol/gasoline and diesel fuel yearly. The numbers are increasing rapidly, especially in China and India.

The word automobile comes, via the French automobile, from the Ancient Greek word αὐτός (autós, "self") and the Latin mobilis ("movable"); meaning a vehicle that moves itself, rather than being pulled or pushed by a separate animal or another vehicle. The alternative name car is believed to originate from the Latin word carrus or carrum ("wheeled vehicle"), or the Middle English word carre ("cart") (from Old North French), or from the Gaulish word karros (a Gallic Chariot).

History


Ferdinand Verbiest, a member of a Jesuit mission in China, designed a steam-powered vehicle around 1672. It was a 65 cm-long scale-model toy for the Chinese Emperor, that was unable to carry a driver or a passenger, but possibly was the first working steam-powered vehicle ('auto-mobile'). It is not known if Verbiest's model was ever built.

Leonty Shamshurenkov, a Russian peasant, constructed a human-pedalled four-wheeled "auto-running" carriage in 1752, and subsequently proposed to equip it with odometer and to use the same principle for making a self-propelling sledge.

Although Nicolas-Joseph Cugnot is often credited with building the first self-propelled mechanical vehicle or automobile in about 1769, by adapting an existing horse-drawn vehicle, this claim is disputed by some, who doubt Cugnot's three-wheeler ever ran or was stable. What is not in doubt is that Richard Trevithick built and demonstrated his Puffing Devil road locomotive in 1801, believed by many to be the first demonstration of a steam-powered road vehicle, although it was unable to maintain sufficient steam pressure for long periods, and would have been of little practical use.

In the 1780s, a Russian inventor of merchant origin, Ivan Kulibin, developed a human-pedalled, three-wheeled carriage with modern features such as a flywheel, brake, gear box, and bearings; however, it was not developed further.

François Isaac de Rivaz, a Swiss inventor, designed the first internal combustion engine, in 1806, which was fueled by a mixture of hydrogen and oxygen and used it to develop the world's first vehicle, albeit rudimentary, to be powered by such an engine. The design was not very successful, as was the case with others, such as Samuel Brown, Samuel Morey, and Etienne Lenoir with his hippomobile, who each produced vehicles (usually adapted carriages or carts) powered by clumsy internal combustion engines.

In November 1881, French inventor Gustave Trouvé demonstrated a working three-wheeled automobile that was powered by electricity. This was at the International Exhibition of Electricity in Paris.

Although several other German engineers (including Gottlieb Daimler, Wilhelm Maybach, and Siegfried Marcus) were working on the problem at about the same time, Karl Benz generally is acknowledged as the inventor of the modern automobile.

An automobile powered by his own four-stroke cycle gasoline engine was built in Mannheim, Germany by Karl Benz in 1885, and granted a patent in January of the following year under the auspices of his major company, Benz & Cie., which was founded in 1883. It was an integral design, without the adaptation of other existing components, and included several new technological elements to create a new concept. This is what made it worthy of a patent. He began to sell his production vehicles in 1888.

Production


The large-scale, production-line manufacturing of affordable automobiles was debuted by Ransom Olds at his Oldsmobile factory in 1902. This concept was greatly expanded by Henry Ford, beginning in 1914.

As a result, Ford's cars came off the line in fifteen minute intervals, much faster than previous methods, increasing productivity eightfold (requiring 12.5 man-hours before, 1 hour 33 minutes after), while using less manpower. It was so successful, paint became a bottleneck. Only Japan black would dry fast enough, forcing the company to drop the variety of colors available before 1914, until fast-drying Duco lacquer was developed in 1926. This is the source of Ford's apocryphal remark, "any color as long as it's black". In 1914, an assembly line worker could buy a Model T with four months' pay.
Ford's complex safety procedures—especially assigning each worker to a specific location instead of allowing them to roam about—dramatically reduced the rate of injury. The combination of high wages and high efficiency is called "Fordism," and was copied by most major industries. The efficiency gains from the assembly line also coincided with the economic rise of the United States. The assembly line forced workers to work at a certain pace with very repetitive motions which led to more output per worker while other countries were using less productive methods.

Fuel and propulsion technologies

Most automobiles in use today are propelled by gasoline (also known as petrol) or diesel internal combustion engines, which are known to cause air pollution and are also blamed for contributing to climate change and global warming. costs of oil-based fuels, tightening environmental laws and restrictions on greenhouse gas emissions are propelling work on alternative power systems for automobiles. Efforts to improve or replace existing technologies include the development of hybrid vehicles, and electric and hydrogen vehicles which do not release pollution into the air.

Safety


While road traffic injuries represent the leading cause in worldwide injury-related deaths, their popularity undermines this statistic.

Mary Ward became one of the first documented automobile fatalities in 1869 in Parsonstown, Ireland and Henry Bliss one of the United States' first pedestrian automobile casualties in 1899 in New York. There are now standard tests for safety in new automobiles, like the EuroNCAP and the US NCAP tests, as well as insurance-backed IIHS tests.

Industry


The automotive industry designs, develops, manufactures, markets, and sells the world's motor vehicles. In 2008, more than 70 million motor vehicles, including cars and commercial vehicles were produced worldwide.

In 2007, a total of 71.9 million new automobiles were sold worldwide: 22.9 million in Europe, 21.4 million in Asia-Pacific, 19.4 million in USA and Canada, 4.4 million in Latin America, 2.4 million in the Middle East and 1.4 million in Africa.[41] The markets in North America and Japan were stagnant, while those in South America and other parts of Asia grew strongly. Of the major markets, China, Russia, Brazil and India saw the most rapid growth.

About 250 million vehicles are in use in the United States. Around the world, there were about 806 million cars and light trucks on the road in 2007; they burn over 260 billion gallons of gasoline and diesel fuel yearly. The numbers are increasing rapidly, especially in China and India. In the opinion of some, urban transport systems based around the car have proved unsustainable, consuming excessive energy, affecting the health of populations, and delivering a declining level of service despite increasing investments. Many of these negative impacts fall disproportionately on those social groups who are also least likely to own and drive cars. The sustainable transport movement focuses on solutions to these problems.

In 2008, with rapidly rising oil prices, industries such as the automotive industry, are experiencing a combination of pricing pressures from raw material costs and changes in consumer buying habits. The industry is also facing increasing external competition from the public transport sector, as consumers re-evaluate their private vehicle usage. half of the US's fifty-one light vehicle plants are projected to permanently close in the coming years, with the loss of another 200,000 jobs in the sector, on top of the 560,000 jobs lost this decade. with robust growth in China, in 2009, this resulted in China becoming the largest automobile producer and market in the wor