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English Electric DEUCE
The DEUCE (''Digital Electronic Universal Computing Engine'') was one of the earliest British commercially available computers, built by English Electric from 1955. It was the production version of the Pilot ACE, itself a cut-down version of Alan Turing's ACE. Hardware description The DEUCE had 1450 thermionic valves, and used mercury delay lines for its main memory; each of the 12 delay lines could store 32 instructions or data words of 32 bits each. It adopted the then high 1 megahertz clock rate of the Pilot ACE. Input/output was via Hollerith 80-column punch-card equipment. The reader read cards at the rate of 200 per minute, while the card punch rate was 100 cards per minute. The DEUCE also had an 8192-word magnetic drum for main storage. To access any of the 256 tracks of 32 words, the drum had one group of 16 read and one group of 16 write heads, each group on independent moveable arms, each capable of moving to one of 16 positions. Access time was 15 mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
English Electric
The English Electric Company Limited (EE) was a British industrial manufacturer formed after World War I by amalgamating five businesses which, during the war, made munitions, armaments and aeroplanes. It initially specialised in industrial electric motors and transformers, locomotives and railway electric traction, traction equipment, diesel engine, diesel motors and steam turbines. Its products were later expanded to include consumer electronics, nuclear reactors, guided missiles, military aircraft and mainframe computers. Two English Electric aircraft designs became landmarks in British aeronautical engineering; the English Electric Canberra, Canberra and the English Electric Lightning, Lightning. In 1960, English Electric Aircraft (40%) merged with Vickers Armstrongs, Vickers (40%) and Bristol Aeroplane Company, Bristol (20%) to form British Aircraft Corporation. In 1968 English Electric's operations were merged with General Electric Company#Further expansion (1961–83), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Punched Tape
file:PaperTapes-5and8Hole.jpg, Five- and eight-hole wide punched paper tape file:Harwell-dekatron-witch-10.jpg, Paper tape reader on the Harwell computer with a small piece of five-hole tape connected in a circle – creating a physical program loop Punched tape or perforated paper tape is a form of data storage that consists of a long strip of paper through which small holes are punched. It was developed from and was subsequently used alongside punched cards, the difference being that the tape is continuous. Punched cards, and chains of punched cards, were used for control of looms in the 18th century. Use for telegraphy systems started in 1842. Punched tapes were used throughout the 19th and for much of the 20th centuries for programmable looms, teleprinter communication, for input to computers of the 1950s and 1960s, and later as a storage medium for minicomputers and Numerical control, CNC machine tools. During the Second World War, high-speed punched tape systems using opti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reverse Polish Notation
Reverse Polish notation (RPN), also known as reverse Łukasiewicz notation, Polish postfix notation or simply postfix notation, is a mathematical notation in which operators ''follow'' their operands, in contrast to prefix or Polish notation (PN), in which operators ''precede'' their operands. The notation does not need any parentheses for as long as each operator has a fixed number of operands. The term ''postfix notation'' describes the general scheme in mathematics and computer sciences, whereas the term ''reverse Polish notation'' typically refers specifically to the method used to enter calculations into hardware or software calculators, which often have additional side effects and implications depending on the actual implementation involving a stack. The description "Polish" refers to the nationality of logician Jan Łukasiewicz, who invented Polish notation in 1924. The first computer to use postfix notation, though it long remained essentially unknown outside of G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Leonard Hamblin
Charles Leonard Hamblin (20 November 1922 – 14 May 1985) was an Australian philosopher, logician, and computer pioneer, as well as a professor of philosophy at the New South Wales University of Technology (now the University of New South Wales) in Sydney. Among his most well-known achievements in the area of computer science was the introduction of Reverse Polish Notation and the use in 1957 of a push-down pop-up stack. This preceded the work of Friedrich Ludwig Bauer and Klaus Samelson on use of a push-pop stack. The stack had been invented by Alan Turing in 1946 when he introduced such a stack in his design of the ACE computer. In philosophy, Hamblin is known for his book ''Fallacies'', a standard work in the area of the false conclusions in logic. In formal semantics, Hamblin is known for his computational model of discourse as well as Hamblin semantics (or alternative semantics), an approach to the semantics of questions. Career and life Hamblin was born in Peter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Assembler Language
In computing, assembly language (alternatively assembler language or symbolic machine code), often referred to simply as assembly and commonly abbreviated as ASM or asm, is any low-level programming language with a very strong correspondence between the instructions in the language and the architecture's machine code instructions. Assembly language usually has one statement per machine instruction (1:1), but constants, comments, assembler directives, symbolic labels of, e.g., memory locations, registers, and macros are generally also supported. The first assembly code in which a language is used to represent machine code instructions is found in Kathleen and Andrew Donald Booth's 1947 work, ''Coding for A.R.C.''. Assembly code is converted into executable machine code by a utility program referred to as an '' assembler''. The term "assembler" is generally attributed to Wilkes, Wheeler and Gill in their 1951 book ''The Preparation of Programs for an Electronic Digit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brian Randell
Brian Randell (born 1936) is a British computer scientist, and emeritus professor at the School of Computing, Newcastle University, United Kingdom. He specialises in research into software fault tolerance and dependability, and is a noted authority on the early pre-1950 history of computing hardware. Biography Randell was employed at English Electric from 1957 to 1964 where he was working on compilers. His work on ALGOL 60 is particularly well known, including the development of the Whetstone compiler for the English Electric KDF9, an early stack machine. In 1964, he joined IBM, where he worked at the Thomas J. Watson Research Center on high performance computer architectures and also on operating system design methodology. In May 1969, he became a professor of computing science at the then named University of Newcastle upon Tyne, where he has worked since then in the area of software fault tolerance and dependability. He is a member of the Special Interest Group ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ALGOL
ALGOL (; short for "Algorithmic Language") is a family of imperative computer programming languages originally developed in 1958. ALGOL heavily influenced many other languages and was the standard method for algorithm description used by the Association for Computing Machinery (ACM) in textbooks and academic sources for more than thirty years. In the sense that the syntax of most modern languages is "Algol-like", it was arguably more influential than three other high-level programming languages among which it was roughly contemporary: FORTRAN, Lisp, and COBOL. It was designed to avoid some of the perceived problems with FORTRAN and eventually gave rise to many other programming languages, including PL/I, Simula, BCPL, B, Pascal, Ada, and C. ALGOL introduced code blocks and the begin...end pairs for delimiting them. It was also the first language implementing nested function definitions with lexical scope. Moreover, it was the first programming language which gave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GEORGE (programming Language)
GEORGE (General Order Generator) is a programming language A programming language is a system of notation for writing computer programs. Programming languages are described in terms of their Syntax (programming languages), syntax (form) and semantics (computer science), semantics (meaning), usually def ... invented by Charles Leonard Hamblin in 1957. It was designed around a push-down pop-up stack for arithmetic operations, and employed reverse Polish notation. The language included loops, subroutines, conditionals, vectors, and matrices. Description Algebraic expressions were written in reverse Polish notation; thus, a + b was written a b +, and similarly for the other arithmetic operations of subtraction, multiplication, and division. The algebraic expression ax^2 + bx + c was written a x dup × × b x × + c +, where 'dup' meant 'duplicate the value'. Following the reverse Polish form, an assignment statement to evaluate the formula y = ax^2 + bx + c was written as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-level Programming Language
A high-level programming language is a programming language with strong Abstraction (computer science), abstraction from the details of the computer. In contrast to low-level programming languages, it may use natural language ''elements'', be easier to use, or may automate (or even hide entirely) significant areas of computing systems (e.g. memory management), making the process of developing a program simpler and more understandable than when using a lower-level language. The amount of abstraction provided defines how "high-level" a programming language is. In the 1960s, a high-level programming language using a compiler was commonly called an ''autocode''. Examples of autocodes are COBOL and Fortran. The first high-level programming language designed for computers was Plankalkül, created by Konrad Zuse. However, it was not implemented in his time, and his original contributions were largely isolated from other developments due to World War II, aside from the language's influe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binary-coded Decimal
In computing and electronic systems, binary-coded decimal (BCD) is a class of binary encodings of decimal numbers where each digit is represented by a fixed number of bits, usually four or eight. Sometimes, special bit patterns are used for a sign or other indications (e.g. error or overflow). In byte-oriented systems (i.e. most modern computers), the term ''unpacked'' BCD usually implies a full byte for each digit (often including a sign), whereas ''packed'' BCD typically encodes two digits within a single byte by taking advantage of the fact that four bits are enough to represent the range 0 to 9. The precise four-bit encoding, however, may vary for technical reasons (e.g. Excess-3). The ten states representing a BCD digit are sometimes called '' tetrades'' (the nibble typically needed to hold them is also known as a tetrade) while the unused, don't care-states are named ''pseudo-tetrad(e)s'', ''pseudo-decimals'', or ''pseudo-decimal digits''. BCD's main virtue, in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alphanumeric
Alphanumericals or alphanumeric characters are any collection of number characters and letters in a certain language. Sometimes such characters may be mistaken one for the other. Merriam-Webster suggests that the term "alphanumeric" may often additionally refer to other symbols, such as punctuation and mathematical symbols. In the POSIX/C Locale (computer software), locale, there are either 36 (A–Z and 0–9, case insensitive) or 62 (A–Z, a–z and 0–9, case-sensitive) alphanumeric characters. Subsets of alphanumeric used in human interfaces When a string of mixed alphabets and numerals is presented for human interpretation, ambiguities arise. The most obvious is the similarity of the letters I, O and Q to the numbers 1 and 0. Therefore, depending on the Record locator, application, various subsets of the alphanumeric were adopted to avoid misinterpretation by humans. In passenger aircraft, aircraft seat maps and seats were designated by row number followed by column le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CRT Display
A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen. The images may represent electrical waveforms on an oscilloscope, a frame of video on an analog television set (TV), digital raster graphics on a computer monitor, or other phenomena like radar targets. A CRT in a TV is commonly called a picture tube. CRTs have also been used as memory devices, in which case the screen is not intended to be visible to an observer. The term ''cathode ray'' was used to describe electron beams when they were first discovered, before it was understood that what was emitted from the cathode was a beam of electrons. In CRT TVs and computer monitors, the entire front area of the tube is scanned repeatedly and systematically in a fixed pattern called a raster. In color devices, an image is produced by controlling the intensity of each of three electron beams, one for each ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
