92 résultats pour "technology"
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Automation.
Not all industries require the same degree of automation. Agriculture, sales, and some service industries are difficult to automate. The agriculture industry may becomemore mechanized, especially in the processing and packaging of foods; however, in many service industries such as supermarkets, for example, a checkout countermay be automated and the shelves or supply bins must still be stocked by hand. Similarly, doctors may consult a computer to assist in diagnosis, but they must makethe final...
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Le Wi-Fi
~ 1 ~ Wi -f i i s a pr etty r e cen t w i r el es s r a di o co mm uni cati o n te c hno l o gy us e d i n par ti cul ar i n co mp uti n g a cti v i ti es . I t i s us ed i n p ar ti c ul ar f o r w i r el es s l o cal n etw o r ks , a nd no w ad ay s i t’s t he f i r s t w ay to ac ces s t he i nter net. What are the advantages and the drawbacks of Wi -Fi technology, and how safe is it ? SUMMARY I - General Presentation .............
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Telescope - astronomy.
Observatory). In some telescopes designed in the 1990s, the mirror’s weight has been dramatically reduced by sandwiching a honeycomb pattern of glass ribs between a thin, butrigid, concave mirror and a flat back plate. Engineers have even developed meniscus mirrors—mirrors that are too thin to support their own weight. An adjustableframework supports the meniscus mirror, and servomechanical actuators, controlled by computer, continually adjust the shape of the mirror as it tracks celestial tar...
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World Energy Supply.
In the 1990s, oil production by non-OPEC countries remained strong and production by OPEC countries rebounded. The result at the end of the 20th century was aworld oil surplus and prices (when adjusted for inflation) that were lower than in 1972. Experts are uncertain about future oil supplies and prices. Low prices have spurred greater oil consumption, and experts question how long world petroleum reservescan keep pace with increased demand. Many of the world’s leading petroleum geologists beli...
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Airplane.
For example, the Anglo-French Concorde, a commercial supersonic aircraft, was generally limited to over-water routes, or to those over sparsely populated regions ofthe world. This limitation impacted the commercial viability of the Concorde, which ended its regular passenger service in October 2003. Designers today believe theycan help lessen the impact of sonic booms created by supersonic airliners but probably cannot eliminate them. One of the most difficult practical barriers to supersonic fl...
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Ancient Greece.
The first culture of Aegean civilization on the Greek mainland is named Mycenaean for the palace at Mycenae on the Pelopónnisos. Scholars call the Mycenaeans the“earliest Greeks” because they are the first people known to have spoken Greek. Mycenaean culture developed later than Minoan. The ancestors of the Mycenaean people wandered onto the mainland from the north and the east from about 4000 to2000 BC, mixing with the people already there, and by about 1400 BC the Mycenaeans had become very...
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Ancient Greece .
The first culture of Aegean civilization on the Greek mainland is named Mycenaean for the palace at Mycenae on the Pelopónnisos. Scholars call the Mycenaeans the“earliest Greeks” because they are the first people known to have spoken Greek. Mycenaean culture developed later than Minoan. The ancestors of the Mycenaean people wandered onto the mainland from the north and the east from about 4000 to2000 BC, mixing with the people already there, and by about 1400 BC the Mycenaeans had become very...
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Ancient Greece - USA History.
The first culture of Aegean civilization on the Greek mainland is named Mycenaean for the palace at Mycenae on the Pelopónnisos. Scholars call the Mycenaeans the“earliest Greeks” because they are the first people known to have spoken Greek. Mycenaean culture developed later than Minoan. The ancestors of the Mycenaean people wandered onto the mainland from the north and the east from about 4000 to2000 BC, mixing with the people already there, and by about 1400 BC the Mycenaeans had become very...
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Rock Music
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INTRODUCTION
Carlos Santana
Mexican-born guitarist Carlos Santana became a superstar in the late 1960s with a string of hits and an appearance at the
famous Woodstock rock festival in 1969.
point (a single pitch sustained through a progression of chords), and the parallel movement of chords, derived from a technique on the electric guitar known as bar-chording. Many elements of African American music have been a continuing source of influence on rock music. These characteristics include riffs (repeated patterns), backbeats (emphasizing the second and fourth beats of each measure; see Musical Rhythm: Pulse and Meter ), call-and-response patterns, blue notes (the use of certain...
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Toys.
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INTRODUCTION
Toys, objects that serve as playthings for children. Although the
clay. These readily available elements were also used to make more elaborate toys as human society advanced. Archaeologists have found primitive, handmade toys such as wooden or cloth dolls, clay marbles, and terracotta figures that date back thousands of years. In ancientEgypt, Greece, and Rome, people placed dolls or clay figures in the graves or tombs of children for them to play with in the afterlife. The yo-yo may seem like a 20th-century fad, but it actually dates back at least 2,500 years...
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San Jose (California) - geography.
San Jose has a rich selection of performing arts, including the San Jose Repertory Theatre, the American Musical Theatre of San Jose, Opera San Jose, Ballet San JoseSilicon Valley, and the Margaret Wingrove Dance Company. Annual events include the San Jose Jazz Festival in August and the San Jose Film Festival, beginning in January.The city has numerous community festivals throughout the year, many celebrating ethnic themes. V RECREATION The largest of the many parks inside San Jose is Alum Roc...
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Supercomputer.
the specific model and configuration of the supercomputer. In July 1995, computer scientists at the University of Tokyo, in Japan, broke the 1 teraflop (1 trillion floating-point operations per second) mark with a computer theydesigned to perform astrophysical simulations. Named GRAPE-4 (GRAvity PipE number 4), this MPP supercomputer consisted of 1,692 interconnected processors. InNovember 1996, Cray Research debuted the CRAY T3E-900, the first commercially available supercomputer to offer teraf...
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Central Processing Unit.
Development of the computer chip started in 1958 when Jack Kilby of Texas Instruments demonstrated that it was possible to integrate the various components of aCPU onto a single piece of silicon. These computer chips were called integrated circuits (ICs) because they combined multiple electronic circuits on the same chip.Subsequent design and manufacturing advances allowed transistor densities on integrated circuits to increase tremendously. The first ICs had only tens of transistorsper chip com...
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Network (computer science).
computer. Since there is only one token in the network, only one computer can transmit information at a time. Token Ring networks are now quite rare. Most LANs nowuse Ethernet technology. International Business Machines Corporation (IBM), the company that invented Token Ring in the early 1980s, no longer promotes thetechnology. In the mid-1990s a new protocol called Asynchronous Transfer Mode (ATM) was introduced. This protocol encodes data in fixed-sized packets called cells rather thanvariable...
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Bangladesch - geographie.
3.3 Religion Zum Islam, der Staatsreligion, bekennen sich rund 87 Prozent der Bevölkerung; die meisten Muslime sind Sunniten. Etwa 12 Prozent der Bevölkerung sind Hindus,außerdem gibt es kleinere Gemeinschaften von Buddhisten, Christen und Anhängern indigener Religionen. 3.3. 1 Feiertage Weltliche Feiertage folgen dem westlichen Jahresrhythmus, die religiösen Feste jedoch dem Mondkalender. Dies erklärt, warum sie jedes Jahr auf einen anderen Tag fallen.Der bengalische Kalender legt die Jahresz...
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Rap
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INTRODUCTION
Jay-Z
Rapper Jay-Z rose to popularity with such albums as Vol.
Run-DMCTypically in rap music, vocalists recite rhyming lyrics in time to a beat that may be sampled from prerecorded music byother groups. Black youths developed rap music on the streets of inner cities in the United States during the 1970s, butthe style has expanded to include a wider variety of performers and audiences. The rap group Run-DMC, shown here, wasa powerful early influence in the genre. The group helped bring rap music into the mainstream when it released “WalkThis Way” (1986), a s...
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Genetic Engineering.
Pseudomonas fluorescens bacterium. The genetically altered Pseudomonas fluorescens bacterium produces light in proportion to the amount of its activity in breaking down the naphthalene, thus providing a way to monitor the efficiency of the process ( see Bioremediation). A3 Medicine In 1982 the United States Food and Drug Administration (FDA) approved for the first time the medical use of a recombinant DNA protein, the hormone insulin, whichhad been cloned in large quantities by inserting th...
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Animation
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INTRODUCTION
Finding Nemo
A clown fish named Marlin, left, and his friend Dory search for Marlin's son in the computer-animated feature film Finding
Nemo (2003).
Animator at WorkAnimators use computers for every part of the animation process, from creating a storyboard (a scene-by-sceneillustration of the plot) to imitating camera movement. This animator is creating a scene for the motion picture Antz(1998).C. Lepetit/Liaison Agency If an animator is basing the animation project on drawings, one of the most common animation techniques, he or she will first create a series of rough sketches thatoften will be filmed in a pencil test (simple line drawings...
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Helicopter.
naturally flaps down so as to increase lift. Flapping allows the differences in lift caused by uneven rotor tip speed to cancel out, producing a stable ride. Many helicoptersuse mechanical hinges with lubricated bearings, but some use flexible straps made of a composite material in order to reduce the required maintenance. Helicopters require different amounts of lift and thrust at different times during flight, because the aerodynamic forces acting on them change during hovering andacceleration...
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Thailand - geographie.
Staatliche Feiertage sind der Neujahrstag, das chinesische Neujahrsfest, der Chakri-Tag (6. April), der Krönungstag (5. Mai), der Geburtstag der Königin (12. August), derChulalongkorn-Tag (23. Oktober), der Geburtstag des Königs (5. Dezember), der Verfassungstag (10. Dezember) und Silvester. Von Bedeutung sind auch diebuddhistischen Feiertage Makha Bucha, Asalaha Bucha und Visakha Bucha, die an wichtige Ereignisse in der Geschichte des Buddhismus erinnern und von Jahr zu Jahr auf unterschie...
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Bangladesh - country.
F Environmental Issues Waterborne diseases such as cholera are a serious threat to public health in Bangladesh. Until the 1970s, many of Bangladesh’s people became sick from drinkingpolluted water drawn from surface rivers. Aid agencies such as the United Nations Children’s Fund (UNICEF) built shallow wells throughout the country to help provide asafe source of drinking water to Bangladesh’s poor. In the 1990s, however, it was discovered that many of these wells were contaminated by arsenic, a...
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St. Louis (city) - geography.
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INTRODUCTION
St. Louis (city) or Saint Louis,
Between 1940 and 1990 the black population in metropolitan St. Louis nearly tripled. Blacks are most heavily concentrated in three areas in the St. Louis metropolitanregion: East Saint Louis, the North Side close to downtown, and an east-west belt extending from the waterfront to beyond Forest Park. In the 19th and early 20th centuries, areas to the north and south of the central business district were settled by immigrant working families from Germany, Ireland,and many Eastern European countrie...
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Internet.
usually pays a fixed monthly fee for a dedicated connection. In exchange, the company providing the connection agrees to relay data between the user’s computer andthe Internet. Dial-up is the least expensive access technology, but it is also the least convenient. To use dial-up access, a subscriber must have a telephone modem, a device thatconnects a computer to the telephone system and is capable of converting data into sounds and sounds back into data. The user’s ISP provides software that con...
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Seattle - geography.
Mountains. The area includes the suburban cities of Bellevue, Kirkland, Redmond, Renton, and Issaquah. The Eastside has become home to dozens of high-technologyindustries including Microsoft Corporation, ATL Ultrasound, Nintendo of America, divisions of The Boeing Company, and many other firms. In the 1960s commutersheaded to Seattle jobs from homes on the Eastside. Today, the “reverse commute” from Seattle homes to jobs on the Eastside is just as heavy, and both streams oftraffic cross the same...
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South Korea - country.
forest habitat, and overhunting. The Siberian tiger has not been sighted in the wild in South Korea since the 1920s; the Asiatic black bear can still be found in someremote mountain areas. Several species of deer are indigenous to the peninsula, including the roe deer, water deer, and Siberian musk deer. The musk deer, which hasbeen overhunted for its musk glands, is legally protected as a threatened species. Smaller mammals indigenous to the peninsula include the wild boar, red fox, badger,rabb...
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Bill Clinton.
When Arkansas governor David Pryor ran for the U.S. Senate in 1978, Clinton ran for governor. He promised to improve the state’s schools and highways and toimprove economic conditions so that more jobs would be created. At that time, the average income of people in Arkansas ranked 49th among the 50 states. Clinton woneasily, receiving 60 percent of the vote against four opponents in the Democratic primary election and 63 percent against the Republican candidate, Lynn Lowe, in thegeneral election...
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Bill Clinton - USA History.
When Arkansas governor David Pryor ran for the U.S. Senate in 1978, Clinton ran for governor. He promised to improve the state’s schools and highways and toimprove economic conditions so that more jobs would be created. At that time, the average income of people in Arkansas ranked 49th among the 50 states. Clinton woneasily, receiving 60 percent of the vote against four opponents in the Democratic primary election and 63 percent against the Republican candidate, Lynn Lowe, in thegeneral election...
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Microeconomics.
changes in any of their underlying determinants. Thus, for example, fairly confident and precise predictions can be made about how changes in consumers' preferencesor in technology are likely to affect demand, supply, and equilibrium output, but only under conditions of perfect competition. Although the model of the firm under conditions of perfect competition is the starting point of the theory of supply in microeconomics, it is generally accepted thatmarkets are not usually characterized by pe...
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NASA - astronomy.
Challenger shuttle after launch in 1986 and the Columbia shuttle during reentry in 2003, killing both crews. Investigations traced the accidents to design flaws and tomanagement problems. Both accidents led to design and procedure changes, and to a temporary stoppage of shuttle flights. Following the Columbia disaster, NASA alsoannounced plans to retire the shuttle in 2010, after completion of the International Space Station (ISS), a human orbital research facility. The Constellation program is...
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Telephone.
digits is dialed. The development of inexpensive and reliable amplification provided by the introduction of the transistor in the 1960s made practical the design of adialing system based on the transmission of relatively low power tones instead of the higher-power dial pulses. Today most telephones have push buttons instead of a rotary dial. Touch-Tone is an optional service, and telephone companies still maintain the ability to receive pulsedialing. Push-button telephones usually have a switch...
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Columbus (Ohio) - geography.
A balance among manufacturing, technology, research, and financial activities has helped Columbus’s economy to continue to boom. Much of the city’s expansion resultsfrom its function as a sophisticated service center. By 1990 manufacturing occupied only 12 percent of the area’s labor force. That contrasted with services, includinggovernment, finance, and transportation and utilities, which accounted for almost 60 percent of all employment. The two largest employers in Columbus are state governme...
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Denver - geography.
Denver is the center of professional sports in the Rocky Mountain region. Major league teams are the Denver Broncos (football), Colorado Rockies (baseball), DenverNuggets (basketball), and Colorado Avalanche (ice hockey). Coors Field (opened in 1995) is the home of the Colorado Rockies. The Broncos began play at the newlyconstructed Invesco Field at Mile High in 2001, and the Nuggets and Avalanche play at the Pepsi Center. The National Western Stock Show and Rodeo, one of thelargest such shows i...
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Ancient Greece - history.
Palace of KnossosThe ancient city of Knossos was a center of the Minoan civilization, an advanced society on Crete named after Minos, a legendaryCretan king. Skilled in such fields as engineering and architecture, the Minoans constructed the palace at Knossos in 1700 bc. Aserious fire at least three centuries later caused the collapse of the palace and foreshadowed the subsequent decline of the city.Wolfgang Kaehler Settlers had begun sailing from Asia Minor to Crete about 6000 BC because the i...
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Police.
body. In larger agencies, executive officers may be selected through a civil service or merit system, after moving through the ranks from patrol officer to sergeant,lieutenant, captain, and (in still larger agencies) deputy or assistant chief. At the county level, the head of the agency usually holds the title sheriff. The sheriff is almost always elected and has the power to appoint deputies. Sheriffs'departments often provide law enforcement services for unincorporated areas of counties and ar...
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Fossil Fuels.
water molecules. This crystalline solid is known as gas hydrate. Because technology for the commercial extraction of gas hydrates has not yet been developed, this typeof fossil fuel is not included in most world energy resource estimates. However, in February 2007 the U.S. Department of Energy completed the drilling of a well toretrieve core samples of gas hydrates found in the Prudhoe Bay region of Alaska’s North Slope. By identifying the nature of these gas hydrates, the Energy Departmenthoped...
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Economics.
Malthus, nature's check was “positive”: “The power of population is so superior to the power of the earth to produce subsistence for man, that premature death must insome shape or other visit the human race.” The shapes it took included war, epidemics, pestilence and plague, human vices, and famine, all combining to level theworld's population with the world's food supply. The only escape from population pressure and the horrors of the positive check was in voluntary limitation of population, no...
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First Americans.
bones and artifacts helped 19th-century archaeologists establish the age of ancient human encampments in Europe. Yet, search as they might, American archaeologists found no comparable evidence of a Pleistocene-era human presence. But several sites revealed stone artifacts thatsome scholars believed looked similar to the ancient stone tools found in Europe. On the basis of this similarity, these experts claimed the American artifacts must be asold. By the 1890s, however, other scholars had challe...
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First Americans - Canadian History.
bones and artifacts helped 19th-century archaeologists establish the age of ancient human encampments in Europe. Yet, search as they might, American archaeologists found no comparable evidence of a Pleistocene-era human presence. But several sites revealed stone artifacts thatsome scholars believed looked similar to the ancient stone tools found in Europe. On the basis of this similarity, these experts claimed the American artifacts must be asold. By the 1890s, however, other scholars had challe...
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Philadelphia (city, Pennsylvania) - geography.
national trend of migration from eastern cities to the warmer climate of the Sun Belt. Whereas in 1950 Philadelphia contained more than 2 million people and ranked as the third largest city in America, the city's population plunged to 1,517,550 by 2000.In 2006, the city's population was estimated at 1,448,394. While the city proper was decreasing in population, the metropolitan area centered on Philadelphia grew. In 2006 the region had 6.2 million inhabitants. Philadelphiaranked as the nation’s...
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Environment.
escape into space of the infrared energy radiated back out by Earth. This process is referred to as the greenhouse effect. These gases, primarily carbon dioxide,methane, nitrous oxide, and water vapor, insulate Earth’s surface, helping to maintain warm temperatures. Without these gases, Earth would be a frozen planet with anaverage temperature of about -18°C (about 0°F) instead of a comfortable 15°C (59°F). If the concentration of these gases rises, they trap more heat within theatmosphere, caus...
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China - country.
North China lies between the Mongolian Steppe on the north and the Yangtze River Basin on the south. It stretches west from the Bo Hai gulf and the Yellow Sea to theeastern edge of the Tibetan Plateau. Administratively, North China includes Beijing and Tianjin municipalities; Shandong and Shanxi provinces; most of Hebei, Henan,and Shaanxi provinces; and portions of Ningxia Hui Autonomous Region and of Jiangsu, Anhui, and Gansu provinces. Humans have lived in the agriculturally rich region of Nor...
- The way in which companies frame themselves, their products and their clients