39 résultats pour "computers"

• computers and religion

• true love

  or to play games. At the time the first computers were built the people maybe thought they   were dangerous and could get out of control. Even before Asimov, some people wrote   about machines that could become mightier than humans. But those presentations said   that a machine, for example a computer, was like a wild beast that could kill you if you did   not pay enough attention. I think Asimov's thoughts about computers and their future were not wrong. It is true that   we try to improve the ...

• Observatory - astronomy.

  Ultraviolet radiation, X rays, and gamma rays have shorter wavelengths than visible light has. These types of radiation tell astronomers about the hottest and mostviolent phenomena in the universe. Earth’s atmosphere blocks most of this radiation, so astronomers must send their observatories above the atmosphere aboardballoons, rockets, or satellites. Ultraviolet telescopes are much like visible light telescopes, but X-ray telescopes must have special nested cylindrical mirrors to prevent Xrays...

• 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...

• Electronic Games.

  arcade game of all time. With Pizza Time Theaters legitimizing the idea of arcades and hits such as Ms. Pac-Man , Asteroids , Donkey Kong , Tempest , Frogger , and Defender bringing new excitement to gaming, the coin-operated video game business boomed. In 1981 Americans spent 75,000 person-years and $5 billion playing video games at anestimated 4,300 arcades in the United States. Many popular arcade games also were translated for use on the Atari 2600 and its chief rivals in the homemarket—M...

• 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,...

• 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...

• 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...

• Animation I 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...

• Computer Animation.

  parametric key-frame animation, interpolates, or blends, the in-between images. Another technique, algorithmic animation, controls motion by applying rules thatgovern how the objects move. When the objects and their behaviors have been specified, each scene is rendered frame-by-frame by the virtual camera and stored;then the final animated feature is played back. Despite the power of today's computers, and the innovations used to accelerate traditional animation processes, modern computer animat...

• Hardware (computer).

  Magnetic tape drives use magnetic tape similar to the tape used in VCR cassettes. Tape drives have a very slow read/write time, but have a very high capacity; in fact,their capacity is second only to hard disk drives. Tape drives are mainly used to back up data. Compact disc drives store information on pits burned into the surface of a disc of reflective material ( see CD-ROM). CD-ROMs can store up to 737 megabytes (MB) of data. A Compact Disc-Recordable (CD-R) or Compact Disc-ReWritable (CD-RW)...

• 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...

• 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...

• 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...

• Artificial Satellite - astronomy.

  The first stage of a multistage rocket consists of rocket engines that provide a huge amount of force, or thrust. The first stage lifts the entire launch vehicle—with itsload of fuel, the rocket body, and the satellite—off the launch pad and into the first part of the flight. After its engines use all their fuel, the first stage portion of therocket separates from the rest of the launch vehicle and falls to Earth. The second stage then ignites, providing the energy necessary to lift the satellit...

• Computer.

  which can activate computer commands in conjunction with voice recognition software. “Tablet” computers are being developed that will allow users to interact with theirscreens using a penlike device. E The Central Processing Unit Information from an input device or from the computer’s memory is communicated via the bus to the central processing unit (CPU), which is the part of the computerthat translates commands and runs programs. The CPU is a microprocessor chip—that is, a single piece of sil...

• 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...

• 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...

• Census.

  Prior to any census, a census agency must develop an accurate list of addresses and maps to ensure that everyone is counted. The U.S. Census Bureau obtainsaddresses primarily from the United States Postal Service and from previous census address lists. It also works closely with state, local, and tribal governments tocompile accurate lists. Finally, census agencies often conduct an extensive marketing campaign before Census Day to remind the general population about theimportance of responding t...

• 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...

• 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...

• Computer Memory.

  been created, information can be retrieved but not changed. Newer technologies allow ROMs to be semi-permanent—that is, the information can be changed, but ittakes several seconds to make the change. For example, a FLASH memory acts like a ROM because values remain stored in memory, but the values can be changed. C External Memory External memory can generally be classified as either magnetic or optical, or a combination called magneto-optical. A magnetic storage device, such as a computer'shar...

• Programming Language.

  Logic languages use logic as their mathematical base. A logic program consists of sets of facts and if-then rules, which specify how one set of facts may be deducedfrom others, for example: If the statement X is true, then the statement Y is false. In the execution of such a program, an input statement can be logically deduced from other statements in the program. Many artificial intelligence programs are writtenin such languages. IV LANGUAGE STRUCTURE AND COMPONENTS Programming languages use...

• Electronic Music I INTRODUCTION Electronic Music, music that requires the use of electronic devices to produce or manipulate sound during its composition and performance.

  III SYNTHESIZERS AND OTHER ELECTRONIC TECHNOLOGY Moog SynthesizerThe musical synthesizer was invented by American Robert Moog. Soon after Moog introduced an early version in 1964, itbecame known as the “Moog Synthesizer,” and then simply as the “Moog.” Here, Japanese composer Isao Tomita uses aMoog synthesizer in his studio.Huynh Cong/AP/Wide World Photos In the 1950s sound synthesizers were developed, principally in the United States. Synthesizers enabled composers to produce sounds electroni...

• 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...

• 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...

• 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...

• Business.

  The most common form of ownership is a sole proprietorship —that is, a business owned by one individual. At the beginning of the 21st century, there were more than 17 million sole proprietorships in the United States. These businesses have the advantage of being easy to set up and to dissolve because few laws exist to regulatethem. Proprietors, as owners, also maintain direct control of their businesses and own all their profits. On the other hand, owners of proprietorships are personallyrespon...

• Cognitive Psychology.

  full richness of people’s cognitive experiences. Describing the act of remembering as a process of storage and retrieval, for example, neglects the subjective experienceof remembering. Another criticism is that information-processing theory may not reflect how the brain actually works. Newer models, such as the parallel distributedprocessing model, try to address this criticism by drawing on studies of brain structure and function. Psychologists continue to debate the adequacy of the information...

• 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...

• Submarine.

  B Propulsion Modern submarines use either diesel-electric or nuclear power to drive the sub's propeller and to provide internal electric power. Diesel-electric power emerged as themost efficient propulsion system for submarines in the early 20th century, following unsuccessful attempts to use steam or gasoline power. While on the surface, thesubmarine uses a diesel engine to drive the propeller and generate electricity. When submerged, a battery-driven electrical motor takes over for propulsion...

• Psychology.

  Clinical psychology is dedicated to the study, diagnosis, and treatment of mental illnesses and other emotional or behavioral disorders. More psychologists work in this field than in any other branch of psychology. In hospitals, community clinics, schools, and in private practice, they use interviews and tests to diagnose depression,anxiety disorders, schizophrenia, and other mental illnesses. People with these psychological disorders often suffer terribly. They experience disturbing symptoms t...

• Accounting and Bookkeeping.

  The proliferation of mandated notes that accompany financial statements is a particularly visible example. Such notes disclose information that is not already included inthe body of the financial statement. One of the very first notes identifies the accounting methods adopted when acceptable alternative methods also exist, or when theunique nature of the company's business justifies an otherwise unconventional approach. The notes also disclose information about lease commitments, contingent liab...

• New Hampshire - geography.

  Washington. D1 Temperature The coldest parts of the state are in the White Mountains and the extreme north. Average January temperatures range from about -11° C (about 12° F) along theCanadian border to about -3° C (about 26° F) along the coast. July temperatures range from about 17° C (about 63° F) in the mountains to about 21° C (about 70° F)in the south. D2 Precipitation Precipitation is evenly distributed throughout the year over most of the state. However, the higher peaks of the White Mo...

• New Hampshire - USA History.

  Washington. D1 Temperature The coldest parts of the state are in the White Mountains and the extreme north. Average January temperatures range from about -11° C (about 12° F) along theCanadian border to about -3° C (about 26° F) along the coast. July temperatures range from about 17° C (about 63° F) in the mountains to about 21° C (about 70° F)in the south. D2 Precipitation Precipitation is evenly distributed throughout the year over most of the state. However, the higher peaks of the White Mo...

• Marketing.

  Where advertising reaches a mass audience, personal or direct selling focuses on one customer at a time. That kind of individual attention makes direct sellingexpensive, but it also makes it effective. As the costs of personal selling have risen, the utilization of salespeople has changed. Simple transactions are completed byclerks. Salespeople are now used primarily where the products are complex and require detailed explanation, customized application, or careful negotiation over priceand paym...

• South Dakota - geography.

  C1 Temperatures Average January temperatures are everywhere less than -4° C (24° F) and decrease to less than -12° C (10° F) in some northern sections. The January temperaturesin Sioux Falls range from -16° to -4° C (3° to 24° F). Nightime lows of -29° C (-20° F) occur during most winters. July averages are in the low and middle 20°s C (lowand middle 70°s F) throughout most of the state, and are somewhat lower in the Black Hills. The average temperature range in Sioux Falls in July is 17° to 30...

• South Dakota - USA History.

  C1 Temperatures Average January temperatures are everywhere less than -4° C (24° F) and decrease to less than -12° C (10° F) in some northern sections. The January temperaturesin Sioux Falls range from -16° to -4° C (3° to 24° F). Nightime lows of -29° C (-20° F) occur during most winters. July averages are in the low and middle 20°s C (lowand middle 70°s F) throughout most of the state, and are somewhat lower in the Black Hills. The average temperature range in Sioux Falls in July is 17° to 30...

• Library (institution).

  rooms, special galleries for exhibitions, auditoriums for lectures or concerts, computer rooms, children’s rooms, photocopy rooms, and classrooms. A3 Lending Materials As part of their mission to provide information resources to the community, public libraries allow users to borrow items from their collections for limited amounts of time.To be eligible to borrow public library materials, a user must register her or his name, address, and other basic information with the local library’s circulat...