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Heath Robinson (codebreaking Machine)
Heath Robinson was a machine used by British codebreakers at the Government Code and Cypher School at Bletchley Park during World War II in cryptanalysis of the Lorenz cipher. This achieved the decryption of messages in the German teleprinter cipher produced by the Lorenz SZ40/42 in-line cipher machine. Both the cipher and the machines were called "Tunny" by the codebreakers, who named different German teleprinter ciphers after fish. It was mainly an electro-mechanical machine, containing no more than a couple of dozen valves (vacuum tubes), and was the predecessor to the electronic Colossus computer. It was dubbed "Heath Robinson" by the Wrens who operated it, after cartoonist William Heath Robinson, who drew immensely complicated mechanical devices for simple tasks, similar to (and somewhat predating) Rube Goldberg in the U.S. The functional specification of the machine was produced by Max Newman. The main engineering design was the work of Frank Morrell at the Post Off ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Working Heath Robinson TNMOC April 2019
Working may refer to: * Work (human activity), intentional activity people perform to support themselves, others, or the community Arts and media * Working (musical), ''Working'' (musical), a 1978 musical * Working (TV series), ''Working'' (TV series), an American sitcom * Working (Caro book), ''Working'' (Caro book), a 2019 book by Robert Caro * Working (Terkel book), ''Working'' (Terkel book), a 1974 book by Studs Terkel * ''Working!!'', a manga by Karino Takatsu * Working (song), "Working" (song), by Tate McRae and Khalid, 2021 Engineering and technology * Cold working or cold forming, the shaping of metal below its recrystallization temperature * Hot working, the shaping of metal above its recrystallization temperature * Multiple working, having more than one locomotive under the control of one driver * Live-line working, the maintenance of electrical equipment while it is energised * Single-line working, using one train track out of two Other uses * Holbrook Working (1895� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications Research Establishment
The Telecommunications Research Establishment (TRE) was the main United Kingdom research and development organisation for radio navigation, radar, infra-red detection for heat seeking missiles, and related work for the Royal Air Force (RAF) during World War II and the years that followed. It was regarded as "the most brilliant and successful of the English wartime research establishments" under "Rowe, who saw more of the English scientific choices between 1935 and 1945 than any single man." The name was changed to Radar Research Establishment in 1953, and again to the Royal Radar Establishment in 1957. This article covers the precursor organizations and the Telecommunications Research Establishment up to the time of the name change. The later work at the site is described in the separate article about RRE. History TRE is best known for work on defensive and offensive radar. TRE also made substantial contributions to radio-navigation and to jamming enemy radio-navigation. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flip-flop (electronics)
In electronics, flip-flops and latches are electronic circuit, circuits that have two stable states that can store state information – a bistable multivibrator. The circuit can be made to change state by signals applied to one or more control inputs and will output its state (often along with its logical complement too). It is the basic storage element in sequential logic. Flip-flops and latches are fundamental building blocks of digital electronics systems used in computers, communications, and many other types of systems. Flip-flops and latches are used as data storage elements to store a single ''bit'' (binary digit) of data; one of its two states represents a "one" and the other represents a "zero". Such data storage can be used for storage of ''state (computer science), state'', and such a circuit is described as sequential logic in electronics. When used in a finite-state machine, the output and next state depend not only on its current input, but also on its current stat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyratron
A thyratron is a type of gas-filled tube used as a high-power electrical switch and controlled rectifier. Thyratrons can handle much greater currents than similar hard-vacuum tubes. Electron multiplication occurs when the gas becomes ionized, producing a phenomenon known as a Townsend discharge. Gases used include mercury vapor, xenon, neon, and (in special high-voltage applications or applications requiring very short switching times) hydrogen. Unlike a vacuum tube (valve), a thyratron cannot be used to amplify signals linearly. In the 1920s, thyratrons were derived from early vacuum tubes such as the UV-200, which contained a small amount of argon gas to increase its sensitivity as a radio signal detector, and the German LRS relay tube, which also contained argon gas. Gas rectifiers, which predated vacuum tubes, such as the argon-filled General Electric " Tungar bulb" and the Cooper-Hewitt mercury-pool rectifier, also provided an influence. Irving Langmuir and G. S. Meikle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ernest Rutherford
Ernest Rutherford, 1st Baron Rutherford of Nelson (30 August 1871 – 19 October 1937) was a New Zealand physicist who was a pioneering researcher in both Atomic physics, atomic and nuclear physics. He has been described as "the father of nuclear physics", and "the greatest experimental physics, experimentalist since Michael Faraday". In 1908, he was awarded the Nobel Prize in Chemistry "for his investigations into the disintegration of the elements, and the chemistry of radioactive substances." He was the first Oceanian Nobel laureate, and the first to perform the awarded work in Canada. Rutherford's discoveries include the concept of radioactive half-life, the radioactive element radon, and the differentiation and naming of Alpha decay, alpha and Beta particle, beta radiation. Together with Thomas Royds, Rutherford is credited with proving that alpha radiation is composed of helium nuclei. In 1911, he theorized that atoms have their charge concentrated in a very small atomi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavendish Laboratory
The Cavendish Laboratory is the Department of Physics at the University of Cambridge, and is part of the School of Physical Sciences. The laboratory was opened in 1874 on the New Museums Site as a laboratory for experimental physics and is named after the British chemist and physicist Henry Cavendish. The laboratory has had a huge influence on research in the disciplines of physics and biology. The laboratory moved to its present site in West Cambridge in 1974. , 30 Cavendish researchers have won Nobel Prizes. Notable discoveries to have occurred at the Cavendish Laboratory include the discovery of the electron, neutron, and structure of DNA. Founding The Cavendish Laboratory was initially located on the New Museums Site, Free School Lane, in the centre of Cambridge. It is named after British chemist and physicist Henry Cavendish for contributions to science and his relative William Cavendish, 7th Duke of Devonshire, who served as chancellor of the university and donated fu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modular Arithmetic
In mathematics, modular arithmetic is a system of arithmetic operations for integers, other than the usual ones from elementary arithmetic, where numbers "wrap around" when reaching a certain value, called the modulus. The modern approach to modular arithmetic was developed by Carl Friedrich Gauss in his book '' Disquisitiones Arithmeticae'', published in 1801. A familiar example of modular arithmetic is the hour hand on a 12-hour clock. If the hour hand points to 7 now, then 8 hours later it will point to 3. Ordinary addition would result in , but 15 reads as 3 on the clock face. This is because the hour hand makes one rotation every 12 hours and the hour number starts over when the hour hand passes 12. We say that 15 is ''congruent'' to 3 modulo 12, written 15 ≡ 3 (mod 12), so that 7 + 8 ≡ 3 (mod 12). Similarly, if one starts at 12 and waits 8 hours, the hour hand will be at 8. If one instead waited twice as long, 16 hours, the hour hand would be on 4. This ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Truth Table
A truth table is a mathematical table used in logic—specifically in connection with Boolean algebra, Boolean functions, and propositional calculus—which sets out the functional values of logical expressions on each of their functional arguments, that is, for each combination of values taken by their logical variables. In particular, truth tables can be used to show whether a propositional expression is true for all legitimate input values, that is, logically valid. A truth table has one column for each input variable (for example, A and B), and one final column showing all of the possible results of the logical operation that the table represents (for example, A XOR B). Each row of the truth table contains one possible configuration of the input variables (for instance, A=true, B=false), and the result of the operation for those values. A proposition's truth table is a graphical representation of its truth function. The truth function can be more useful for mathema ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exclusive Or
Exclusive or, exclusive disjunction, exclusive alternation, logical non-equivalence, or logical inequality is a logical operator whose negation is the logical biconditional. With two inputs, XOR is true if and only if the inputs differ (one is true, one is false). With multiple inputs, XOR is true if and only if the number of true inputs is odd. It gains the name "exclusive or" because the meaning of "or" is ambiguous when both operands are true. XOR ''excludes'' that case. Some informal ways of describing XOR are "one or the other but not both", "either one or the other", and "A or B, but not A and B". It is symbolized by the prefix operator J Translated as and by the infix operators XOR (, , or ), EOR, EXOR, \dot, \overline, \underline, , \oplus, \nleftrightarrow, and \not\equiv. Definition The truth table of A\nleftrightarrow B shows that it outputs true whenever the inputs differ: Equivalences, elimination, and introduction Exclusive disjunction essentially ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boolean Algebra (logic)
In mathematics and mathematical logic, Boolean algebra is a branch of algebra. It differs from elementary algebra in two ways. First, the values of the variable (mathematics), variables are the truth values ''true'' and ''false'', usually denoted by 1 and 0, whereas in elementary algebra the values of the variables are numbers. Second, Boolean algebra uses logical operators such as Logical conjunction, conjunction (''and'') denoted as , disjunction (''or'') denoted as , and negation (''not'') denoted as . Elementary algebra, on the other hand, uses arithmetic operators such as addition, multiplication, subtraction, and division. Boolean algebra is therefore a formal way of describing logical operations in the same way that elementary algebra describes numerical operations. Boolean algebra was introduced by George Boole in his first book ''The Mathematical Analysis of Logic'' (1847), and set forth more fully in his ''An Investigation of the Laws of Thought'' (1854). According to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuum Tube
A vacuum tube, electron tube, thermionic valve (British usage), or tube (North America) is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. It takes the form of an evacuated tubular envelope of glass or sometimes metal containing electrodes connected to external connection pins. The type known as a thermionic tube or thermionic valve utilizes thermionic emission of electrons from a hot cathode for fundamental Electronics, electronic functions such as signal amplifier, amplification and current Rectifier, rectification. Non-thermionic types such as vacuum phototubes achieve electron emission through the photoelectric effect, and are used for such purposes as the detection of light and measurement of its intensity. In both types the electrons are accelerated from the cathode to the anode by the electric field in the tube. The first, and simplest, vacuum tube, the diode or Flem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
