78 résultats pour "network"
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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...
- Do people give social network too much power
- Cable News Network [CNN] - médias & information.
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social network
Before the invention of social networks, peoples communicated in writing through various media such as letters and mainly face to face or using more traditional means of communication such as radio, television, fax, telephones… Nowaday, communication is more in the social network. Social networks have opened up new communication possibilities, but also many dangers. First, let’s see what a social network is and why we use them, then the different social networks and finally, their goals an...
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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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Telecommunications.
commonly referred to as wireless communications, use technologies such as cordless telephones, cellular radio telephones, pagers, and satellites. Wirelesscommunications offer increased mobility and flexibility. In the future some experts believe that wireless devices will also offer high-speed Internet access. C Wires and Cables Wires and cables were the original medium for telecommunications and are still the primary means for telephone connections. Wireline transmission evolved fromtelegraph...
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Mars (planet) - astronomy.
The Martian core is probably much like Earth’s, consisting mostly of iron, with a small amount of nickel. If other light elements, particularly sulfur, exist there as well, thecore may be larger than presently thought. From studying Earth’s magnetic field and core, scientists theorize that the motions of the liquid rock in Earth’s core generateits magnetic field. Mars does not have a significant magnetic field, so scientists believe that Mars’s core is probably solid. However, spacecraft data in...
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Cellular Radio Telephone.
There were more than 120 million wireless subscribers in the United States in 2001, according to the Cellular Telecommunications and Internet Association, with thenumber of new users increasing significantly each year. Forecasters and regulators did not anticipate this growth, however. Network equipment and start-up costs weresubstantial, and the cost to consumers was high. Providers had limited their networks to a small group of high-volume business users. Eventually, the providersrecognized th...
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Artificial Intelligence.
Work in AI has primarily focused on two broad areas: developing logic-based systems that perform common-sense and expert reasoning, and using cognitive andbiological models to simulate and explain the information-processing capabilities of the human brain. In general, work in AI can be categorized within three research anddevelopment types: symbolic, connectionist, and evolutionary. Each has characteristic strengths and weaknesses. A Symbolic AI Symbolic AI is based in logic. It uses sequences...
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Wireless Communications.
were large, heavy units. After the invention of the transistor in 1948, radios shrank in size to small handheld radio transceivers. Public two-way radios with severalfrequency options are widely available as well. Usually limited in range to a few miles, these units are great aids for such mobile professionals as construction workers,film crews, event planners, and security personnel. Simpler two-way radios, called walkie-talkies, have been popular children’s toys for years. Most walkie-talkiesb...
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September 11 Attacks - U.
around and flew it back toward Washington, D.C. Flying low and fast, the airplane hit the Pentagon at 9:37 AM. In a bit of good fortune, the plane crashed into the west side of the building, which had recently been reinforced with stronger construction and blast-resistant windows in order to withstand a terrorist attack. Even so, theplane penetrated three of the Pentagon’s five concentric rings, taking a chunk out of the building and incinerating dozens of offices and the people who worked in t...
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Atificiel
Sustainability 2019,11 , 189 2 of 24Since the 1980s, many research was conducted to minimize the error of prediction through a method dubbed as gradient descent. This method is referred to as a Backpropagation algorithm for the training of the ANNs and it was applied to solve problems in different domains using few hidden layers [ 5,6]. Today, the availability of data has introduced the concept of machine learning as a subcategory to AI. Machine learning implies coding the computers to behave l...
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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...
- EARN (European Academic Research Network).
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Microsoft Corporation (entreprise).
3.5 Diversification des activités Au milieu des années 1990, Microsoft élargit son activité vers les médias, les loisirs et les industries de la communication en lançant MSN (Microsoft Network) en 1995 etMSNBC en 1996. La même année, la société introduit également Windows CE, un système d’exploitation pour assistants personnels. En 1997, elle achète WebTV Network (fabricant de composants permettant de relier la télévision à l’Internet) pour 425 millions de dollars (soit environ autant d’euros)...
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Virus (computer).
how closely it resembles a virus. It relies on experience with previous viruses to predict the likelihood that a suspicious file is an as-yet unidentified or unclassified newvirus. Other types of antiviral software include monitoring software and integrity-shell software. Monitoring software is different from scanning software. It detects illegal orpotentially damaging viral activities such as overwriting computer files or reformatting the computer's hard drive. Integrity-shell software establis...
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Health Insurance.
needs services. Essentially, individuals make regular payments to the plan rather than having to pay especially large sums at any one time in the event of sudden illnessor injury. In this way, the group as a whole funds expensive treatments for those few who need them. Many people believe that in addition to providing financial stability, health insurance can promote good health. Supporters of this idea claim that by lowering thepersonal cost of services, insurance induces individuals to seek he...
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Australia - country.
itself forms most of the border between New South Wales and Victoria. Considerable lengths of the Murray, Darling, and Murrumbidgee rivers are navigable during thewet seasons. The central plains region, also known as the Channel Country, is interlaced by a network of rivers. During the rainy season these rivers flood the low-lying countryside,but in dry months they become merely a series of water holes. The Victoria, Daly, and Roper rivers drain a section of the Northern Territory. In Queensland...
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Australia - Geography.
itself forms most of the border between New South Wales and Victoria. Considerable lengths of the Murray, Darling, and Murrumbidgee rivers are navigable during thewet seasons. The central plains region, also known as the Channel Country, is interlaced by a network of rivers. During the rainy season these rivers flood the low-lying countryside,but in dry months they become merely a series of water holes. The Victoria, Daly, and Roper rivers drain a section of the Northern Territory. In Queensland...
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World Wide Web.
browser does not display the URL for the user. Instead, to indicate that an item is selectable, the browser changes the color of the item on the screen and keeps theURL associated with the link hidden. When a user clicks on an item that corresponds to a selectable link, the browser consults the hidden information to find theappropriate URL, which the browser then follows to the selected page. Because a link can point to any page in the Web, the links are known as hyperlinks. See also Hypermedia...
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Technology.
loose soil in this region, known as the Fertile Crescent, was easily scratched for planting, and an abundance of trees was available for firewood. By 5000 BC, farming communities were established in areas known today as Syria, Turkey, Lebanon, Israel, Jordan, Greece, and the islands of Crete and Cyprus. Agricultural societies in these places constructed stone buildings, used the sickle to harvest grain, developed a primitive plowstick, and advanced their skills inmetalworking. Trade in flint al...
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Republic of the Congo - country.
rate of 50 CFA francs equal to 1 French franc was in force from 1948 to 1994, when the CFA franc was devalued by 50 percent. The leading commercial banks are theBanque Internationale du Congo and the Union Congolaise de Banques. E Foreign Trade In 2000 imports cost $930 million and exports earned $2.09 billion. The Congo engages in considerable trade with the nearby countries of Cameroon, the CentralAfrican Republic, and Gabon, with which it is joined in the Customs and Economic Union of Centra...
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Anatomy.
The body defends itself against foreign proteins and infectious microorganisms by means of a complex dual system that depends on recognizing a portion of the surfacepattern of the invader. The two parts of the system are termed cellular immunity, in which lymphocytes are the effective agent, and humoral immunity, based on theaction of antibody molecules. When particular lymphocytes recognize a foreign molecular pattern (termed an antigen), they release antibodies in great numbers; other lymphocy...
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Chicago (city, Illinois) - geography.
VI EDUCATIONAL AND CULTURAL INSTITUTIONS Chicago has one of the largest public school systems in the United States. The Chicago Board of Education administers the system in a centralized fashion; in recentyears it has been experimenting with local school councils as a means of partial devolution of authority. These councils, established in 1989, have authority in severalareas, including the ability to approve budgets and curriculum. In addition, Chicago has many private schools, including larg...
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Manitoba - Geography.
E Plant Life Forests cover 66 percent of Manitoba. The main forest area is divided into the boreal forest and the mixed-wood forest. The boreal, or northern, forest containsconiferous (cone-bearing) trees, especially white and black spruce, balsam fir, and jack pine. South of the boreal forest is the mixed-wood forest, which contains conifers as well as such deciduous trees as white birch, aspen, poplar, and Manitoba maple. Prairie land is found in the southwest, where the natural vegetation i...
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Manitoba - Canadian History.
E Plant Life Forests cover 66 percent of Manitoba. The main forest area is divided into the boreal forest and the mixed-wood forest. The boreal, or northern, forest containsconiferous (cone-bearing) trees, especially white and black spruce, balsam fir, and jack pine. South of the boreal forest is the mixed-wood forest, which contains conifers as well as such deciduous trees as white birch, aspen, poplar, and Manitoba maple. Prairie land is found in the southwest, where the natural vegetation i...
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Social Networking
WOUTERS Laura 6B Miss Musyck YOUNES Clara March 2013 Advantages There are many advantages of using social networks: 1. Worldwide Connectivity: It is a way of communication known in the World and because of this; it is easy for two people from different continents to communicate. Now with Smartphones it is even easier to connect to any social network. There is nothing easier or faster to search in than social networking. If you want to find “ a romance, a new job, a locating assistance...
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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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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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France - country.
In both the Paris and Aquitaine basins, fertile soils derived from limestone and wind-deposited dust, called loess, have supported prosperous agriculture since ancienttimes. Other lowlands in France are scattered and relatively small. They include the Alsace Plain in the east, bordering Germany, the valley of the Rhône River in thesoutheast, and the Languedoc Plain along the Mediterranean coast. A2 Uplands France contains several regions of uplands, the worn down remains of ancient mountain sys...
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Advertising.
Advertising agencies make money in a variety of ways. When the agency uses the client’s advertising budget to buy time for an ad on the radio or on television or whenit buys space for an ad in a newspaper or magazine, the media outlet allows the agency to keep 15 percent of the cost of the space or the time as a commission. The15 percent commission has become an advertising industry standard and usually accounts for the largest portion of the agency’s income. Agencies also charge clientsfor the...
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United States History - U.
and improved upon the designs of Arab sailing ships and learned to mount cannons on those ships. In the 15th century they began exploring the west coast ofAfrica—bypassing Arab merchants to trade directly for African gold and slaves. They also colonized the Madeira Islands, the Azores, and the Cape Verde Islands andturned them into the first European slave plantations. The European explorers were all looking for an ocean route to Asia. Christopher Columbus sailed for the monarchs of Spain in 149...
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United States History - U.
and improved upon the designs of Arab sailing ships and learned to mount cannons on those ships. In the 15th century they began exploring the west coast ofAfrica—bypassing Arab merchants to trade directly for African gold and slaves. They also colonized the Madeira Islands, the Azores, and the Cape Verde Islands andturned them into the first European slave plantations. The European explorers were all looking for an ocean route to Asia. Christopher Columbus sailed for the monarchs of Spain in 149...
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Native Americans of Middle and South America.
A line that snakes across central Mexico near the Tropic of Cancer forms the northern boundary of Mesoamerica; north of this line rainfall sharply declines and theclimate is much drier. The ancient civilizations of Mesoamerica all arose and developed in the area between this line and the Guatemalan highlands far to the south. Richvolcanic soils are found throughout much of the region. A2 People and Languages Mesoamerica was a great melting pot, home to many peoples and interrelated cultures. In...
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Computer Security.
might deny usage to legitimate users, and they ensure that information received from an outside source is expected and does not contain computer viruses. VII INTRUSION DETECTION SYSTEMS Security software called intrusion detection systems may be used in computers to detect unusual and suspicious activity and, in some cases, stop a variety of harmfulactions by authorized or unauthorized persons. Abuse and misuse of sensitive system and application programs and data such as password, inventory,...
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Iraq - country.
The Euphrates begins in Turkey, crosses Syria, and enters Iraq at Abū Kam āl. The flow of the Euphrates into Iraq has been greatly reduced by dams built by Turkeyand Syria. The gradient of the Euphrates above the town of H īt, in west central Iraq, is steep. In the 2,640 km (1,640 mi) from its source in Turkey to H īt, the river fallsfrom 3,000 m (10,000 ft) to a low water elevation of 50 m (170 ft) above sea level, an average drop of 1 m per km (6 ft per mi). In Iraq below H īt the fall is very...
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Computer Science.
theoretical research is called algorithmic complexity. Computer scientists in this field seek to develop techniques for determining the inherent efficiency of algorithmswith respect to one another. Another area of theoretical research called computability theory seeks to identify the inherent limits of computation. Software engineers use programming languages to communicate algorithms to a computer. Natural languages such as English are ambiguous—meaning that theirgrammatical structure and vocab...
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Earthquake.
III CAUSES Most earthquakes are caused by the sudden slip along geologic faults. The faults slip because of movement of the Earth’s tectonic plates. This concept is called theelastic rebound theory. The rocky tectonic plates move very slowly, floating on top of a weaker rocky layer. As the plates collide with each other or slide past eachother, pressure builds up within the rocky crust. Earthquakes occur when pressure within the crust increases slowly over hundreds of years and finally exceeds...
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Comparative Anatomy.
In comparing two species, anatomists have to be careful to differentiate between homologous structures, which are ones that have evolved from a shared ancestor, andanalogous structures, which have developed from different origins. Homologous structures are built on the same underlying plan. A human arm, a bat’s wing, and awhale’s flipper look quite different from the outside, but the bones inside reveal that these limbs all have the same basic structure. Analogous structures, by contrast,often l...
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Roman Empire .
A Government Augustus did not derive his power from any single office, but from the authority of his name and his victory. In fact, he carefully pieced together a patchwork of powersthat allowed him to be an absolute ruler and yet avoid the hatred Caesar aroused as dictator. In Latin, the name Augustus implies both political authority and religiousrespect. The Romans had for some time called Octavian imperator , a title once awarded to victorious generals that soon became associated with the r...
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Roman Empire - History.
A Government Augustus did not derive his power from any single office, but from the authority of his name and his victory. In fact, he carefully pieced together a patchwork of powersthat allowed him to be an absolute ruler and yet avoid the hatred Caesar aroused as dictator. In Latin, the name Augustus implies both political authority and religiousrespect. The Romans had for some time called Octavian imperator , a title once awarded to victorious generals that soon became associated with the r...
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World War I .
and troops to Europe from the United States and other overseas sources. In 1914 Britain implemented a sea blockade of Germany to prevent the delivery of importssuch as food and war materials. The same year, Germany began using submarines to disrupt Allied seaborne traffic and prevent supplies from reaching Britain. In 1915Germany instituted a submarine blockade around Britain. From February 1915 to September 1915 and again in 1917, Germany used unrestricted submarine warfare,sinking ships withou...
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Italy - country.
C Natural Resources Italy is poor in natural resources. Much of the land is unsuitable for agriculture because of mountainous terrain or unfavorable climate. Italy, moreover, lacks substantialdeposits of basic natural resources such as coal, iron, and petroleum. Natural gas is the country’s most important mineral resource. Other deposits include feldspar andpumice. Many of Italy’s mineral deposits on the islands of Sicily and Sardinia had been heavily depleted by the early 1990s. Italy is rich...
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Recherche opérationnelle
–2– -lam´ethode des coupes et la m´ethode par s´eparation et ´evaluation pour la r´esolution de programmes lin´eaires qui imposent `a certaines variables d’ˆetre ` a valeurs enti`eres ou mˆeme binaires; - l’analyse post-optimale, qui d´etermine la variation de la solution en fonction d’un changement des valeurs des param`etres du programme. Le troisi`eme chapitre traite de la th´eorie des jeux `a deux personnes et `a somme z´ero et s’appuie fortement sur les deux chapitres pr´ec´edents. Au quatr...
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White Paper: SMEs in Morocco
In addition to these structural weaknesses of the economic fabric, there is the predominance of the informal sector. If there are no figures on the portion of black economy in Morocco, but it is still a fact that nobody can deny: a large number of businesses, particularly small ones (the majority of the economic fabric) are only partially applying government regulation and particularly fiscal. This part of the informal activity is not i...
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SMEs in Morocco
In addition to these structural weaknesses of the economic fabric, there is the predominance of the informal sector. If there are no figures on the portion of black economy in Morocco, but it is still a fact that nobody can deny: a large number of businesses, particularly small ones (the majority of the economic fabric) are only partially applying government regulation and particularly fiscal. This part of the informal activity is not i...
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Sierra Leone (country) - country.
commodities such as palm oil, palm kernels, coffee, cacao, ginger, kola nuts, and piassava (palm fibers) are grown for export. Cattle, goats, and sheep are raised, andthe fishing industry is of increasing importance. B Mining Gem and industrial diamonds are the leading mineral products of Sierra Leone. In 2004, 309,390 carats of gem-quality diamonds were produced. Rutile, a titanium oreof which Sierra Leone has one of the world’s largest deposits, and bauxite are also mined in large quantities....
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Canadian Pacific Railway - Canadian History.
roads constructed inland from the lakeshore. However, this changed with the outbreak in Saskatchewan of the Northwest Rebellion by Louis Riel and his supportersagainst the authority of the Canadian government in March 1885. Despite the fact that the railway was not completed, a contingent of troops was able to reachWinnipeg from Montréal in only seven days, much faster than they could have gone overland, and get from there to Saskatchewan in time to successfully put down therebellion. This actio...
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Pittsburgh - geography.
College of Allegheny County (1966), with branches in the city and suburbs. Pittsburgh has many outstanding cultural institutions. The Oakland district is where Carnegie Mellon University and the University of Pittsburgh are located. The CarnegieMuseums of Pittsburgh include The Carnegie Museum of Art (including the Scaife Galleries), which holds a distinguished motion-picture and video collection and a uniquestudy of architecture; the Carnegie Museum of Natural History, which displays an extensi...
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Brian Mulroney.
At the party convention Mulroney was one of the candidates who ran against Clark. This time Mulroney did not have to contend with a rival candidate from Québec. Healso had the support of the remnants of the Diefenbaker faction—who disliked Clark even more than they disliked Mulroney. Mulroney was also endorsed by asubstantial group of members of Parliament; this endorsement helped allay concerns about whether he could provide effective leadership in Parliament. Mulroney waselected leader of the...