|
Microcomputer Software
A microcomputer is a small, relatively inexpensive computer having a central processing unit (CPU) made out of a microprocessor. The computer also includes memory and input/output (I/O) circuitry together mounted on a printed circuit board (PCB). Microcomputers became popular in the 1970s and 1980s with the advent of increasingly powerful microprocessors. The predecessors to these computers, mainframes and minicomputers, were comparatively much larger and more expensive (though indeed present-day mainframes such as the IBM System z machines use one or more custom microprocessors as their CPUs). Many microcomputers (when equipped with a keyboard and screen for input and output) are also personal computers (in the generic sense). An early use of the term ''personal computer'' in 1962 predates microprocessor-based designs. ''(See "Personal Computer: Computers at Companies" reference below)''. A ''microcomputer'' used as an embedded control system may have no human-readable input a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Dying Night
"The Dying Night" is a science fiction short story by American writer Isaac Asimov. The story first appeared in the July 1956 issue of ''The Magazine of Fantasy & Science Fiction'', and was reprinted in the collections ''Nine Tomorrows'' (1959), ''Asimov's Mysteries'' (1968), and ''The Best of Isaac Asimov'' (1973). "The Dying Night" is Asimov's third Wendell Urth story. Plot summary Three astronomers, who have been working on the Moon, Mercury and the asteroid Ceres, meet for the first time in ten years at a convention on Earth. They also meet a former colleague of theirs, Romero Villiers, who had to stay on Earth because of illness. Villiers claims to have invented a mass-transference/teleportation device, but dies under suspicious circumstances before he can demonstrate the device to his friends. Another scientist who has seen the device demonstrated suspects that Villiers has been murdered by one of his classmates, and he questions them. In the course of his investigation, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
User Interface
In the industrial design field of human–computer interaction, a user interface (UI) is the space where interactions between humans and machines occur. The goal of this interaction is to allow effective operation and control of the machine from the human end, while the machine simultaneously feeds back information that aids the operators' decision-making process. Examples of this broad concept of user interfaces include the interactive aspects of computer operating systems, hand tools, heavy machinery operator controls and process controls. The design considerations applicable when creating user interfaces are related to, or involve such disciplines as, ergonomics and psychology. Generally, the goal of user interface design is to produce a user interface that makes it easy, efficient, and enjoyable (user-friendly) to operate a machine in the way which produces the desired result (i.e. maximum usability). This generally means that the operator needs to provide minimal input ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
7400 Series
The 7400 series of integrated circuits (ICs) are a popular logic family of transistor–transistor logic (TTL) logic chips. In 1964, Texas Instruments introduced the SN5400 series of logic chips, in a ceramic semiconductor package. A low-cost plastic package SN7400 series was introduced in 1966 which quickly gained over 50% of the logic chip market, and eventually becoming ''de facto'' standardized electronic components. Over the decades, many generations of pin-compatible descendant families evolved to include support for low power CMOS technology, lower supply voltages, and surface mount packages. Overview The 7400 series contains hundreds of devices that provide everything from basic logic gates, flip-flops, and counters, to special purpose bus transceivers and arithmetic logic units (ALU). Specific functions are described in a list of 7400 series integrated circuits. Some TTL logic parts were made with an extended military-specification temperature range. These pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semiconductor Memory
Semiconductor memory is a digital electronic semiconductor device used for digital data storage, such as computer memory. It typically refers to devices in which data is stored within metal–oxide–semiconductor (MOS) memory cells on a silicon integrated circuit memory chip. There are numerous different types using different semiconductor technologies. The two main types of random-access memory (RAM) are static RAM (SRAM), which uses several transistors per memory cell, and dynamic RAM (DRAM), which uses a transistor and a MOS capacitor per cell. Non-volatile memory (such as EPROM, EEPROM and flash memory) uses floating-gate memory cells, which consist of a single floating-gate transistor per cell. Most types of semiconductor memory have the property of random access, which means that it takes the same amount of time to access any memory location, so data can be efficiently accessed in any random order. This contrasts with data storage media such as hard disks and CDs which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proof Of Concept
Proof of concept (POC or PoC), also known as proof of principle, is a realization of a certain method or idea in order to demonstrate its feasibility, or a demonstration in principle with the aim of verifying that some concept or theory has practical potential. A proof of concept is usually small and may or may not be complete. These collaborative trials aim to test feasibility of business concepts and proposals to solve business problems and accelerate business innovation goals. A proof of value (PoV) is sometimes used along proof of concept, and differs by focusing more on demonstrating the potential customers use case and value, and is usually less in-depth than a proof of concept. Usage history The term has been in use since 1967. In a 1969 hearing of the Committee on Science and Astronautics, Subcommittee on Advanced Research and Technology, ''proof of concept'' was defined as following: One definition of the term "proof of concept" was by Bruce Carsten in the context o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Random-access Memory
Random-access memory (RAM; ) is a form of computer memory that can be read and changed in any order, typically used to store working Data (computing), data and machine code. A Random access, random-access memory device allows data items to be read (computer), read or written in almost the same amount of time irrespective of the physical location of data inside the memory, in contrast with other direct-access data storage media (such as hard disks, CD-RWs, DVD-RWs and the older Magnetic tape data storage, magnetic tapes and drum memory), where the time required to read and write data items varies significantly depending on their physical locations on the recording medium, due to mechanical limitations such as media rotation speeds and arm movement. RAM contains multiplexer, multiplexing and demultiplexing circuitry, to connect the data lines to the addressed storage for reading or writing the entry. Usually more than one bit of storage is accessed by the same address, and RAM ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Byte
The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable unit of memory in many computer architectures. To disambiguate arbitrarily sized bytes from the common 8-bit definition, network protocol documents such as The Internet Protocol () refer to an 8-bit byte as an octet. Those bits in an octet are usually counted with numbering from 0 to 7 or 7 to 0 depending on the bit endianness. The first bit is number 0, making the eighth bit number 7. The size of the byte has historically been hardware-dependent and no definitive standards existed that mandated the size. Sizes from 1 to 48 bits have been used. The six-bit character code was an often-used implementation in early encoding systems, and computers using six-bit and nine-bit bytes were common in the 1960s. These systems often had memory words ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Altair 8800
The Altair 8800 is a microcomputer designed in 1974 by MITS and based on the Intel 8080 CPU. Interest grew quickly after it was featured on the cover of the January 1975 issue of Popular Electronics and was sold by mail order through advertisements there, in ''Radio-Electronics'', and in other hobbyist magazines. The Altair is widely recognized as the spark that ignited the microcomputer revolution as the first commercially successful personal computer. The computer bus designed for the Altair was to become a ''de facto'' standard in the form of the S-100 bus, and the first programming language for the machine was Microsoft's founding product, Altair BASIC. "This announcement ltair 8800ranks with IBM's announcement of the System/360 a decade earlier as one of the most significant in the history of computing." History While serving at the Air Force Weapons Laboratory at Kirtland Air Force Base, Ed Roberts and Forrest M. Mims III decided to use their electronics background ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micral
Micral is a series of microcomputers produced by the French company Réalisation d'Études Électroniques (R2E), beginning with the Micral N in early 1973. The Micral N was the first commercially available microprocessor-based computer. In 1986, three judges at The Computer Museum, Boston – Apple II designer and Apple Inc. co-founder Steve Wozniak, early MITS employee and ''PC World'' publisher David Bunnell, and the museum's associate director and curator Oliver Strimpel – awarded the title of "first personal computer using a microprocessor" to the 1973 Micral. The Micral N was the earliest commercial, non-kit personal computer based on a microprocessor (in this case, the Intel 8008). The Computer History Museum currently says that the Micral is one of the earliest commercial, non-kit personal computers. The 1971 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
François Gernelle
François Gernelle (born December 20, 1944) is a French engineer, computer scientist and entrepreneur famous for inventing the first micro-computer using a micro-processor, the Micral N. Education In the late 1960s, Gernelle earned an engineering degree at the Conservatoire National des Arts et Métiers. In 1978, he earned a Ph.D in computer science at the Pierre Mendès-France University of Grenoble. Career Intertechnique and R2E In 1968, he was hired by Intertechnique, a company specialized in electronic measurement for aviation. There he discovered the Intel 8008 microprocessor and imagined all its potential applications. As his hierarchy didn't share his views on the i8008 development capacity, he resigned in 1972 and joined R2E R, or r, is the eighteenth letter of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''ar'' (pronounced ), plural ''ars'', or in Ir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hygrometry
Psychrometrics (or psychrometry, ; also called hygrometry) is the field of engineering concerned with the physical and thermodynamic properties of gas-vapor mixtures. Common applications Although the principles of psychrometry apply to any physical system consisting of gas-vapor mixtures, the most common system of interest is the mixture of water vapor and air, because of its application in heating, ventilation, and air-conditioning and meteorology. In human terms, our thermal comfort is in large part a consequence of not just the temperature of the surrounding air, but (because we cool ourselves via perspiration) the extent to which that air is saturated with water vapor. Many substances are hygroscopic, meaning they attract water, usually in proportion to the relative humidity or above a critical relative humidity. Such substances include cotton, paper, cellulose, other wood products, sugar, calcium oxide (burned lime) and many chemicals and fertilizers. Industries that us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
