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Gimbal
A gimbal is a pivoted support that permits rotation of an object about an axis. A set of three gimbals, one mounted on the other with orthogonal pivot axes, may be used to allow an object mounted on the innermost gimbal to remain independent of the rotation of its support (e.g. vertical in the first animation). For example, on a ship, the gyroscopes, shipboard compasses, stoves, and even drink holders typically use gimbals to keep them upright with respect to the horizon despite the ship's pitching and rolling. The gimbal suspension used for mounting compasses and the like is sometimes called a Cardan suspension after Italian mathematician and physicist Gerolamo Cardano (1501–1576) who described it in detail. However, Cardano did not invent the gimbal, nor did he claim to. The device has been known since antiquity, first described in the 3rd c. BC by Philo of Byzantium, although some modern authors support the view that it may not have a single identifiable inventor. Histo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gyroscope Operation
A gyroscope (from Ancient Greek γῦρος ''gŷros'', "round" and σκοπέω ''skopéō'', "to look") is a device used for measuring or maintaining Orientation (geometry), orientation and angular velocity. It is a spinning wheel or disc in which the axis of rotation (spin axis) is free to assume any orientation by itself. When rotating, the orientation of this axis is unaffected by tilting or rotation of the mounting, according to the conservation of angular momentum. Gyroscopes based on other operating principles also exist, such as the microchip-packaged Vibrating structure gyroscope#MEMS gyroscopes, MEMS gyroscopes found in electronic devices (sometimes called gyrometers), solid-state ring laser gyroscope, ring lasers, fibre optic gyroscopes, and the extremely sensitive quantum gyroscope. Applications of gyroscopes include inertial navigation systems, such as in the Hubble Space Telescope, or inside the steel hull of a submerged submarine. Due to their precision, gyrosc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gyroscope
A gyroscope (from Ancient Greek γῦρος ''gŷros'', "round" and σκοπέω ''skopéō'', "to look") is a device used for measuring or maintaining orientation and angular velocity. It is a spinning wheel or disc in which the axis of rotation (spin axis) is free to assume any orientation by itself. When rotating, the orientation of this axis is unaffected by tilting or rotation of the mounting, according to the conservation of angular momentum. Gyroscopes based on other operating principles also exist, such as the microchip-packaged MEMS gyroscopes found in electronic devices (sometimes called gyrometers), solid-state ring lasers, fibre optic gyroscopes, and the extremely sensitive quantum gyroscope. Applications of gyroscopes include inertial navigation systems, such as in the Hubble Space Telescope, or inside the steel hull of a submerged submarine. Due to their precision, gyroscopes are also used in gyrotheodolites to maintain direction in tunnel mining. Gyroscopes ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gerolamo Cardano
Gerolamo Cardano (; also Girolamo or Geronimo; french: link=no, Jérôme Cardan; la, Hieronymus Cardanus; 24 September 1501– 21 September 1576) was an Italian polymath, whose interests and proficiencies ranged through those of mathematician, physician, biologist, physicist, chemist, astrologer, astronomer, philosopher, writer, and gambler. He was one of the most influential mathematicians of the Renaissance, and was one of the key figures in the foundation of probability and the earliest introducer of the binomial coefficients and the binomial theorem in the Western world. He wrote more than 200 works on science. Cardano partially invented and described several mechanical devices including the combination lock, the gimbal consisting of three concentric rings allowing a supported compass or gyroscope to rotate freely, and the Cardan shaft with universal joints, which allows the transmission of rotary motion at various angles and is used in vehicles to this day. He made sig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Censer
A censer, incense burner, perfume burner or pastille burner is a vessel made for burning incense or perfume in some solid form. They vary greatly in size, form, and material of construction, and have been in use since ancient times throughout the world. They may consist of simple earthenware bowls or fire pots to intricately carved silver or gold vessels, small table top objects a few centimetres tall to as many as several metres high. Many designs use openwork to allow a flow of air. In many cultures, burning incense has spiritual and religious connotations, and this influences the design and decoration of the censer. Often, especially in Western contexts, "censer" is used for pieces made for religious use, especially those on chains that are swung through the air to spread the incense smoke widely, while "perfume burner" is used for objects made for secular use. The original meaning of pastille was a small compressed mixture of aromatic plant material and charcoal that was l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compass
A compass is a device that shows the cardinal directions used for navigation and geographic orientation. It commonly consists of a magnetized needle or other element, such as a compass card or compass rose, which can pivot to align itself with magnetic north. Other methods may be used, including gyroscopes, magnetometers, and GPS receivers. Compasses often show angles in degrees: north corresponds to 0°, and the angles increase clockwise, so east is 90°, south is 180°, and west is 270°. These numbers allow the compass to show azimuths or bearings which are commonly stated in degrees. If local variation between magnetic north and true north is known, then direction of magnetic north also gives direction of true north. Among the Four Great Inventions, the magnetic compass was first invented as a device for divination as early as the Chinese Han Dynasty (since c. 206 BC),Li Shu-hua, p. 176 and later adopted for navigation by the Song Dynasty Chinese during the 11th centur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philo Of Byzantium
Philo of Byzantium ( el, , ''Phílōn ho Byzántios'', ca. 280 BC – ca. 220 BC), also known as Philo Mechanicus, was a Greek engineer, physicist and writer on mechanics, who lived during the latter half of the 3rd century BC. Although he was from Byzantium he lived most of his life in Alexandria, Egypt. He was probably younger than Ctesibius, though some place him a century earlier. Life and works Philo was the author of a large work, ''Mechanike syntaxis'' (Compendium of Mechanics), which contained the following sections: * ''Isagoge'' (εἰσαγωγή) – an introduction to mathematics * ''Mochlica'' (μοχλικά) – on general mechanics * ''Limenopoeica'' (λιμενοποιικά) – on harbour building * ''Belopoeica'' (βελοποιικά) – on artillery * ''Pneumatica'' (πνευματικά) – on devices operated by air or water pressure * ''Automatopoeica'' (αὐτοματοποιητικά) – on mechanical toys and diversions * ''Parasceuastica'' ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Han Dynasty
The Han dynasty (, ; ) was an imperial dynasty of China (202 BC – 9 AD, 25–220 AD), established by Liu Bang (Emperor Gao) and ruled by the House of Liu. The dynasty was preceded by the short-lived Qin dynasty (221–207 BC) and a warring interregnum known as the ChuHan contention (206–202 BC), and it was succeeded by the Three Kingdoms period (220–280 AD). The dynasty was briefly interrupted by the Xin dynasty (9–23 AD) established by usurping regent Wang Mang, and is thus separated into two periods—the Western Han (202 BC – 9 AD) and the Eastern Han (25–220 AD). Spanning over four centuries, the Han dynasty is considered a golden age in Chinese history, and it has influenced the identity of the Chinese civilization ever since. Modern China's majority ethnic group refers to themselves as the "Han people", the Sinitic language is known as "Han language", and the written Chinese is referred to as "Han characters". The emperor was at the pinnacle of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sima Xiangru
Sima Xiangru ( , ; c. 179117BC) was a Chinese musician, poet, and politician who lived during the Western Han dynasty. Sima is a significant figure in the history of Classical Chinese poetry, and is generally regarded as the greatest of all composers of Chinese ''fu'' rhapsodies. His poetry includes his invention or at least development of the ''fu'' form, applying new metrical rhythms to the lines of poetry, which he mixed with lines of prose, and provided with several of what would in ensuing centuries become among a group of common set topics for this genre. Sima Xiangru was also versatile enough to write in the ''Chu ci'' style, while it was enjoying a renaissance, and he also wrote lyrics in what would become known as the ''yuefu'' formal style. Early life and career Sima Xiangru was born in the commandery of Shu (now Sichuan Province) in the early 2nd century BC. His birth year is generally given as 179BC, but other sources give it variously as 172, 171, or 169BC. Mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stove
A stove or range is a device that burns fuel or uses electricity to generate heat inside or on top of the apparatus, to be used for general warming or cooking. It has evolved highly over time, with cast-iron and induction versions being developed. Stoves can be powered with many fuels, such as electricity, gasoline, wood, and coal. Due to concerns about air pollution, efforts have been made to improve stove design. Pellet stoves are a type of clean-burning stove. Air-tight stoves are another type that burn the wood more completely and therefore, reduce the amount of the combustion by-products. Another method of reducing air pollution is through the addition of a device to clean the exhaust gas, for example, a filter or afterburner. Research and development on safer and less emission releasing stoves is continuously evolving. Etymology The term "stove" is derived from the Old English word ''stofa'', indicating any individual enclosed space or room; "stove" may sometimes still ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver
Silver is a chemical element with the Symbol (chemistry), symbol Ag (from the Latin ', derived from the Proto-Indo-European wikt:Reconstruction:Proto-Indo-European/h₂erǵ-, ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. The metal is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc Refining (metallurgy), refining. Silver has long been valued as a precious metal. Silver metal is used in many bullion coins, sometimes bimetallism, alongside gold: while it is more abundant than gold, it is much less abundant as a native metal. Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Augustus
Caesar Augustus (born Gaius Octavius; 23 September 63 BC – 19 August AD 14), also known as Octavian, was the first Roman emperor; he reigned from 27 BC until his death in AD 14. He is known for being the founder of the Roman Principate, which is the first phase of the Roman Empire, and Augustus is considered one of the greatest leaders in human history. The reign of Augustus initiated an imperial cult as well as an era associated with imperial peace, the ''Pax Romana'' or ''Pax Augusta''. The Roman world was largely free from large-scale conflict for more than two centuries despite continuous wars of imperial expansion on the empire's frontiers and the year-long civil war known as the "Year of the Four Emperors" over the imperial succession. Originally named Gaius Octavius, he was born into an old and wealthy equestrian branch of the plebeian ''gens'' Octavia. His maternal great-uncle Julius Caesar was assassinated in 44 BC, and Octavius was named in Caesar' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Athenaeus Mechanicus
Athenaeus Mechanicus is the author of a book on siegecraft, ''On Machines'' ( grc, Περὶ μηχανημάτων '). He is identified by modern scholars with Athenaeus of Seleucia, a member of the Peripatetic school active in the mid-to-late 1st century BC, at Rome and elsewhere.Serafina Cuomo, review of Gatto 2010Bryn Mawr Classical Review 2010.11.35/ref>Duncan B. Campbell, review of Whitehead and Blyth 2004/ref> Life Strabo mentions a contemporary of his, Athenaeus of Seleucia, a Peripatetic philosopher. He was for some time the leading demagogue in his native city, but afterwards came to Rome and became acquainted with Lucius Licinius Varro Murena. On the discovery of the plot which the latter, with Fannius Caepio, had entered into against Augustus, Athenaeus accompanied him in his flight. He was retaken, but pardoned by Augustus, as there was no evidence of his having taken a more active part in the plot. William Smith, ''Dictionary of Greek and Roman Biography and Mythol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
