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Military Computers
This article specifically addresses U.S. armed forces military computers and their use. History Some of the earliest computers were military computers. Military requirements for portability and ruggedness led to some of the earliest transistorized computers, such as the 1958 AN/USQ-17, the 1959 AN/MYK-1 (MOBIDIC), the 1960 M18 FADAC, and the 1962 D-17B; the earliest integrated-circuit based computer, the 1964 D-37C; as well as one of the earliest laptop computers, the 1982 Grid Compass. Military requirements for a computer small enough to fit through a submarine's hatch led to the AN/UYK-1. Construction Typically a military computer is much more robust than an industrial computer enclosure. Most electronics will be protected with a layer of conformal coating. There will be more structure inside to support the components, the plug-in cards will be individually supported and secured to assure they do not pop out of their sockets, the processor and heat sink will be secured, mem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AN/USQ-17
The AN/USQ-17 or Naval Tactical Data System (NTDS) computer referred to in Sperry Rand documents as the Univac M-460, was Seymour Cray's last design for UNIVAC. UNIVAC later released a commercial version, the UNIVAC 490. That system was later upgraded to a multiprocessor configuration as the 494. In accordance with the Joint Electronics Type Designation System (JETDS), the "''AN/USQ-17''" designation represents the 17th design of an Army-Navy Electronics, electronic device for general utility special combination equipment. The JETDS system also now is used to name all Department of Defense electronic systems. Overview The machine was the size and shape of a refrigerator, about four feet high (roughly 1.20 meters), with a hinged lid for access. Shortly after completing the prototype design, Cray left to join Control Data Corporation. When the Navy awarded Sperry Rand a US$50 million contract to build the AN/USQ-17, Univac engineers redesigned the entire machine from scratch using s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MIL-S-901D
United States Military Standard, Military Specification MIL-S-901D is for high-impact mechanical shock which applies to equipment mounted on Ship, ships. Its publication date was Mar 17, 1989. Two levels apply: Grade A items are items which are essential to the safety and continued combat capability of the ship; Grade B items are items whose operation is not essential to the safety and combat capability of the ship but which could become a hazard to personnel, to Grade A items, or to the ship as a whole as a result of exposure to Shock wave, shock. "Grade C", signifying that no shock qualification is required, is also sometimes referenced in acquisition documents even though the term has no official standing in the specification document. Qualification testing is performed on a specified machine or on a barge floating in a pond where an explosive charge is detonated at various distances and depths in the pond to impart shock to the Barge, barges. The MIL-S-901D specification cov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thin Client
In computer networking, a thin client, sometimes called slim client or lean client, is a simple (low-Computer performance, performance) computer that has been Program optimization, optimized for Remote desktop, establishing a remote connection with a Server (computing), server-based computing environment. They are sometimes known as ''network computers'', or in their simplest form as ''zero clients''. The server does most of the work, which can include launching software programs, performing calculations, and Data storage, storing data. This contrasts with a rich client or a conventional personal computer; the former is also intended for working in a client–server model but has significant local processing power, while the latter aims to perform its function mostly locally. Thin clients occur as components of a broader computing infrastructure, where many clients share their computations with a server or server farm. The server-side infrastructure uses cloud computing softw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flash Memory
Flash memory is an Integrated circuit, electronic Non-volatile memory, non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR gate, NOR and NAND gate, NAND logic gates. Both use the same cell design, consisting of floating-gate MOSFETs. They differ at the circuit level, depending on whether the state of the bit line or word lines is pulled high or low; in NAND flash, the relationship between the bit line and the word lines resembles a NAND gate; in NOR flash, it resembles a NOR gate. Flash memory, a type of floating-gate memory, was invented by Fujio Masuoka at Toshiba in 1980 and is based on EEPROM technology. Toshiba began marketing flash memory in 1987. EPROMs had to be erased completely before they could be rewritten. NAND flash memory, however, may be erased, written, and read in blocks (or pages), which generally are much smaller than the entire devi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Processing Unit
A central processing unit (CPU), also called a central processor, main processor, or just processor, is the primary Processor (computing), processor in a given computer. Its electronic circuitry executes Instruction (computing), instructions of a computer program, such as arithmetic, logic, controlling, and input/output (I/O) operations. This role contrasts with that of external components, such as main memory and I/O circuitry, and specialized coprocessors such as graphics processing units (GPUs). The form, CPU design, design, and implementation of CPUs have changed over time, but their fundamental operation remains almost unchanged. Principal components of a CPU include the arithmetic–logic unit (ALU) that performs arithmetic operation, arithmetic and Bitwise operation, logic operations, processor registers that supply operands to the ALU and store the results of ALU operations, and a control unit that orchestrates the #Fetch, fetching (from memory), #Decode, decoding and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Equipment In Hazardous Areas
In electrical engineering, electrical and safety engineering, safety engineering, hazardous locations (HazLoc, pronounced ''haz·lōk'') are places where fire or explosion hazards may exist. Sources of such hazards include gases, vapors, dust explosion, dust, fibers, and flyings, which are combustibility and flammability, combustible or flammable. Electrical equipment installed in such locations can provide an ignition source, due to electrical arcing, or high temperatures. Technical standard, Standards and regulations exist to identify such locations, classify the hazards, and design equipment for safe use in such locations. Overview A light switch may cause a small, harmless spark when switched on or off. In an ordinary household this is of no concern, but if a flammable atmosphere is present, the arc might start an explosion. In many industrial, commercial, and scientific settings, the presence of such an atmosphere is a common, or at least commonly possible, occurrence. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
