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Pinwheel Calculator
A pinwheel calculator is a class of mechanical calculator described as early as 1685, and popular in the 19th and 20th century, calculating via wheels whose number of teeth were adjustable. These wheels, also called pinwheels, could be set by using a side lever which could expose anywhere from 0 to 9 teeth, and therefore when coupled to a counter they could, at each rotation, add a number from 0 to 9 to the result. By linking these wheels with carry mechanisms a new kind of calculator engine was invented. Turn the wheels one way and one performs an addition, the other way a subtraction. As part of a redesign of the arithmometer, they reduced by an order of magnitude the cost and the size of mechanical calculators on which one could easily do the four basic operations (add, subtract, multiply and divide). Pinwheel calculators became extremely popular with the success of Thomas' Arithmometer (manufactured 1850s) and Odhner Arithmometer (manufactured 1890s). History In "Mach ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roue à Nombre De Dents Variables
Roue is a synonym for rake (character). Roue or La Roue may also refer to: *''La Roue'', a 1923 film by Abel Gance *La Roue (Brussels), a district **La Roue/Het Rad metro station, in Brussels *Rõue, a village in Estonia *William James Roué (1879–1970), a naval architect famous for his design of the ''Bluenose'' fishing schooner {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Warsaw, Poland
Warsaw, officially the Capital City of Warsaw, is the capital and largest city of Poland. The metropolis stands on the River Vistula in east-central Poland. Its population is officially estimated at 1.86 million residents within a greater metropolitan area of 3.27 million residents, which makes Warsaw the 6th most-populous city in the European Union. The city area measures and comprises 18 districts, while the metropolitan area covers . Warsaw is classified as an alpha global city, a major political, economic and cultural hub, and the country's seat of government. It is also the capital of the Masovian Voivodeship. Warsaw traces its origins to a small fishing town in Masovia. The city rose to prominence in the late 16th century, when Sigismund III decided to move the Polish capital and his royal court from Kraków. Warsaw surpassed Gdańsk as Poland's most populous city by the 18th century. It served as the capital of the Polish–Lithuanian Commonwealth u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Division (mathematics)
Division is one of the four basic operations of arithmetic. The other operations are addition, subtraction, and multiplication. What is being divided is called the ''dividend'', which is divided by the ''divisor'', and the result is called the ''quotient''. At an elementary level the division of two natural numbers is, among other Quotition and partition, possible interpretations, the process of calculating the number of times one number is contained within another. For example, if 20 apples are divided evenly between 4 people, everyone receives 5 apples (see picture). However, this number of times or the number contained (divisor) need not be integers. The division with remainder or Euclidean division of two natural numbers provides an integer ''quotient'', which is the number of times the second number is completely contained in the first number, and a ''remainder'', which is the part of the first number that remains, when in the course of computing the quotient, no further ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiplication
Multiplication is one of the four elementary mathematical operations of arithmetic, with the other ones being addition, subtraction, and division (mathematics), division. The result of a multiplication operation is called a ''Product (mathematics), product''. Multiplication is often denoted by the cross symbol, , by the mid-line dot operator, , by juxtaposition, or, in programming languages, by an asterisk, . The multiplication of whole numbers may be thought of as repeated addition; that is, the multiplication of two numbers is equivalent to adding as many copies of one of them, the ''multiplicand'', as the quantity of the other one, the ''multiplier''; both numbers can be referred to as ''factors''. This is to be distinguished from term (arithmetic), ''terms'', which are added. :a\times b = \underbrace_ . Whether the first factor is the multiplier or the multiplicand may be ambiguous or depend upon context. For example, the expression 3 \times 4 , can be phrased as "3 ti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Control Knob
{{more citations needed, date=January 2017 A control knob is a rotary device used to provide manual input adjustments to a mechanical/ electrical system when grasped and turned by a human operator, so that differing extent of knob rotation corresponds to different desired input. Control knobs are a simpler type of input hardware and one of the most common components in control systems, and are found on all sorts of devices from taps and gas stoves to optical microscopes, potentiometers, radio tuners and digital cameras, as well as in aircraft cockpits.https://www.amazon.com/b?node=16412811 Operation A control knob works by turning a shaft which connects to the component which produces the actual input. Common control components used include potentiometers, variable capacitors, and rotary switches. An example where the knob does not produce a variation in an electrical signal may be found in many toasters, where the darkness knob moves the thermostat A thermostat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lever
A lever is a simple machine consisting of a beam (structure), beam or rigid rod pivoted at a fixed hinge, or '':wikt:fulcrum, fulcrum''. A lever is a rigid body capable of rotating on a point on itself. On the basis of the locations of fulcrum, load, and effort, the lever is divided into Lever#Types of levers, three types. It is one of the six simple machines identified by Renaissance scientists. A lever amplifies an input force to provide a greater output force, which is said to provide leverage, which is mechanical advantage gained in the system, equal to the ratio of the output force to the input force. As such, the lever is a mechanical advantage device, trading off force against movement. Etymology The word "lever" entered English language, English around 1300 from . This sprang from the stem of the verb ''lever'', meaning "to raise". The verb, in turn, goes back to , itself from the adjective ''levis'', meaning "light" (as in "not heavy"). The word's primary origin is the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Felix Edmundovich Dzerzhinsky
Felix Edmundovich Dzerzhinsky (; ; – 20 July 1926), nicknamed Iron Felix (), was a Soviet revolutionary and politician of Polish origin. From 1917 until his death in 1926, he led the first two Soviet secret police organizations, the Cheka and the OGPU, establishing Chronology of Soviet secret police agencies, state security organs for the Bolsheviks, Bolshevik government. He was a key architect of the Red Terror * * and de-Cossackization. Born to a Polish family of Szlachta, noble descent in their Dzerzhinovo, Ozhyemblovo Estate (in 1881 named Dzerzhinovo), in Russian Partition, Russian Poland, Dzerzhinsky embraced revolutionary politics from a young age, and was active in the Social Democracy of the Kingdom of Poland and Lithuania party. Active in Kaunas and Warsaw, he was frequently arrested and underwent several exiles to Siberia, from which he escaped every time. He evaded the tsarist secret police, the Okhrana, whose work he took interest in. Dzerzhinsky participated in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet Union
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet Union, it dissolved in 1991. During its existence, it was the list of countries and dependencies by area, largest country by area, extending across Time in Russia, eleven time zones and sharing Geography of the Soviet Union#Borders and neighbors, borders with twelve countries, and the List of countries and dependencies by population, third-most populous country. An overall successor to the Russian Empire, it was nominally organized as a federal union of Republics of the Soviet Union, national republics, the largest and most populous of which was the Russian SFSR. In practice, Government of the Soviet Union, its government and Economy of the Soviet Union, economy were Soviet-type economic planning, highly centralized. As a one-party state go ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheka
The All-Russian Extraordinary Commission ( rus, Всероссийская чрезвычайная комиссия, r=Vserossiyskaya chrezvychaynaya komissiya, p=fsʲɪrɐˈsʲijskəjə tɕrʲɪzvɨˈtɕæjnəjə kɐˈmʲisʲɪjə, links=yes), abbreviated as VChK ( rus, ВЧК, p=vɛ tɕe ˈka), and commonly known as the Cheka ( rus, ЧК, p=tɕɪˈka), was the first Soviet secret police organization. It was established on by the Council of People's Commissars of the Russian SFSR, and was led by Felix Dzerzhinsky. By the end of the Russian Civil War in 1921, the Cheka had at least 200,000 personnel. Ostensibly created to protect the October Revolution from "class enemies" such as the bourgeoisie and members of the clergy, the Cheka soon became a tool of repression wielded against all political opponents of the Bolshevik regime. The organization had responsibility for counterintelligence, oversight of the loyalty of the Red Army, and protection of the country's borders, as well ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Felix Dzerzhinsky
Felix Edmundovich Dzerzhinsky (; ; – 20 July 1926), nicknamed Iron Felix (), was a Soviet revolutionary and politician of Polish origin. From 1917 until his death in 1926, he led the first two Soviet secret police organizations, the Cheka and the OGPU, establishing state security organs for the Bolshevik government. He was a key architect of the Red Terror * * and de-Cossackization. Born to a Polish family of noble descent in their Ozhyemblovo Estate (in 1881 named Dzerzhinovo), in Russian Poland, Dzerzhinsky embraced revolutionary politics from a young age, and was active in the Social Democracy of the Kingdom of Poland and Lithuania party. Active in Kaunas and Warsaw, he was frequently arrested and underwent several exiles to Siberia, from which he escaped every time. He evaded the tsarist secret police, the Okhrana, whose work he took interest in. Dzerzhinsky participated in the failed 1905 Revolution, and after a final arrest in 1912, was imprisoned until the Febru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Europe
Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east. Europe shares the landmass of Eurasia with Asia, and of Afro-Eurasia with both Africa and Asia. Europe is commonly considered to be Boundaries between the continents#Asia and Europe, separated from Asia by the Drainage divide, watershed of the Ural Mountains, the Ural (river), Ural River, the Caspian Sea, the Greater Caucasus, the Black Sea, and the waterway of the Bosporus, Bosporus Strait. "Europe" (pp. 68–69); "Asia" (pp. 90–91): "A commonly accepted division between Asia and Europe ... is formed by the Ural Mountains, Ural River, Caspian Sea, Caucasus Mountains, and the Black Sea with its outlets, the Bosporus and Dardanelles." Europe covers approx. , or 2% of Earth#Surface, Earth's surface (6.8% of Earth's land area), making it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilgott Theophil Odhner
Willgodt Theophil Odhner (; 10 August 1845 – ) was a Swedish engineer and entrepreneur, working in St. Petersburg, Russia. He was the inventor of the Odhner Arithmometer, which by the 1940s was one of the most popular type of portable mechanical calculator in the world.Trogemann G., Nitussov A.: ''Computing in Russia'', page 39-45, GWV-Vieweg, 2001, According to a brochure distributed by Odhner's company at the Paris World exposition of 1900 "...Odhner had, in 1871, an opportunity to repair a Thomas calculating machine and then became convinced that it is possible to solve the problem of mechanical calculation by a simpler and more appropriate way". It took him 19 years to perfect the design of this new machine so it could be manufactured effectively. Early years Odhner studied at the Royal Institute of Technology in Stockholm from 1864 to 1867 but left before graduating. At age 23, in 1868, he moved to Saint Petersburg, Russia, even though he didn't speak any Russian. As soo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
