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Gimbals
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. Gyroscope ... [...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] |
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 ... [...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 stil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wu Zetian
Wu Zetian (17 February 624 – 16 December 705), personal name Wu Zhao, was the ''de facto'' ruler of the Tang dynasty from 665 to 705, ruling first through others and then (from 690) in her own right. From 665 to 690, she was first empress consort of the Tang dynasty (as wife of the Emperor Gaozong) and then, after his death, empress dowager (ruling through her sons Emperors Zhongzong and Ruizong). Unprecedented in Chinese history, she subsequently founded and ruled as empress regnant of the Wu Zhou dynasty of China from 690 to 705. She was the only female sovereign in the history of China widely regarded as legitimate. Under her 40-year reign, China grew larger, becoming one of the great powers of the world, its culture and economy were revitalized, and corruption in the court was reduced. She was removed from power in a coup and died a few months later. In early life, Wu was the concubine of Emperor Taizong. After his death, she married his ninth son and successor ... [...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 Cae ... [...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 Myt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancient Roman
In modern historiography, ancient Rome refers to Roman civilisation from the founding of the city of Rome in the 8th century BC to the collapse of the Western Roman Empire in the 5th century AD. It encompasses the Roman Kingdom (753–509 BC), Roman Republic (509–27 BC) and Roman Empire (27 BC–476 AD) until the fall of the western empire. Ancient Rome began as an Italic settlement, traditionally dated to 753 BC, beside the River Tiber in the Italian Peninsula. The settlement grew into the city and polity of Rome, and came to control its neighbours through a combination of treaties and military strength. It eventually dominated the Italian Peninsula, assimilated the Greek culture of southern Italy ( Magna Grecia) and the Etruscan culture and acquired an Empire that took in much of Europe and the lands and peoples surrounding the Mediterranean Sea. It was among the largest empires in the ancient world, with an estimated 50 to 90 million inhabitants, roughly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andrew Wilson (classical Archaeologist)
Andrew Ian Wilson (born 29 February 1968) is a British classical archaeologist and Head of School of Archaeology at the University of Oxford. He was director of the Oxford Institute of Archaeology from 2009 to 2011. Wilson's main research interests are the economy of the Roman world, Greek and Roman water supply, and ancient technology. Early life and education Wilson was educated at the Perse School, Cambridge, and at Corpus Christi College, Oxford, where he studied Literae Humaniores (Classics) from 1987 to 1991. From 1991 to 1993 he worked as a computer consultant for the electronics firm Eurotherm, before returning to Oxford to study for his doctorate (1993 to 1997), a social and technological study on water management and usage in Roman North Africa, supervised by John Lloyd. Academic career From 1996 to 2000 he was a Fellow by Examination in Classical Archaeology at Magdalen College, Oxford, and spend nine months at the British School at Rome as a Rome Scholar in 1999 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hellenistic
In Classical antiquity, the Hellenistic period covers the time in Mediterranean history after Classical Greece, between the death of Alexander the Great in 323 BC and the emergence of the Roman Empire, as signified by the Battle of Actium in 31 BC and the conquest of Ptolemaic Egypt the following year. The Ancient Greek word ''Hellas'' (, ''Hellás'') was gradually recognized as the name for Greece, from which the word ''Hellenistic'' was derived. "Hellenistic" is distinguished from "Hellenic" in that the latter refers to Greece itself, while the former encompasses all ancient territories under Greek influence, in particular the East after the conquests of Alexander the Great. After the Macedonian invasion of the Achaemenid Empire in 330 BC and its disintegration shortly after, the Hellenistic kingdoms were established throughout south-west Asia ( Seleucid Empire, Kingdom of Pergamon), north-east Africa ( Ptolemaic Kingdom) and South Asia ( Greco-Bactrian Kingdom, Indo-Gree ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interpolation (manuscripts)
An interpolation, in relation to literature and especially ancient manuscripts, is an entry or passage in a text that was not written by the original author. As there are often several generations of copies between an extant copy of an ancient text and the original, each handwritten by different scribes, there is a natural tendency for extraneous material to be inserted into such documents over time. Overview Interpolations originally may be inserted as an authentic explanatory note (for example, ), but may also be included for fraudulent purposes. The forged passages and works attributed to the Pseudo-Isidore are an example of the latter. Similarly, the letters of Ignatius of Antioch were interpolated by Apollinarian heretics, three centuries after the originals were written. Charters and legal texts are also subject to forgery of this kind. In the 13th century a medieval romance, the Prose ''Tristan'', inserted another prose romance, the Vulgate ''Queste del Saint Graal'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
