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Wang-wang
A siren is a loud noise-making device. Civil defense sirens are mounted in fixed locations and used to warn of natural disasters or attacks. Sirens are used on emergency service vehicles such as ambulances, police cars, and fire engines. There are two general types: mechanical and electronic. Many fire sirens (used for calling the volunteer fire fighters) serve double duty as tornado or civil defense sirens, alerting an entire community of impending danger. Most fire sirens are either mounted on the roof of a fire station or on a pole next to the fire station. Fire sirens can also be mounted on or near government buildings, on tall structures such as water towers, as well as in systems where several sirens are distributed around a town for better sound coverage. Most fire sirens are single tone and mechanically driven by electric motors with a rotor attached to the shaft. Some newer sirens are electronically driven speakers. Fire sirens are often called "fire whistles", "fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Sirens Pavian By Telegrafia
Electronic may refer to: *Electronics, the science of how to control electric energy in semiconductor * ''Electronics'' (magazine), a defunct American trade journal * Electronic storage, the storage of data using an electronic device * Electronic commerce or e-commerce, the trading in products or services using computer networks, such as the Internet * Electronic publishing or e-publishing, the digital publication of books and magazines using computer networks, such as the Internet *Electronic engineering, an electrical engineering discipline Entertainment * Electronic (band), an English alternative dance band ** ''Electronic'' (album), the self-titled debut album by British band Electronic *Electronic music, a music genre * Electronic musical instrument * Electronic game, a game that employs electronics See also * Electronica, an electronic music genre *Consumer electronics Consumer electronics or home electronics are electronic ( analog or digital) equipment intended for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adolphe Ganot
Adolphe Ganot (born 1804 in Rochefort, Charente-Maritime Rochefort ( oc, Ròchafòrt), unofficially Rochefort-sur-Mer (; oc, Ròchafòrt de Mar, link=no) for disambiguation, is a city and commune in Southwestern France, a port on the Charente estuary. It is a subprefecture of the Charente-Maritime ..., France; died 1887 in Paris Françoise Khantine-Langlois (2006?)Un siècle de physique à travers un manuel à succès: le traité de physique de Ganot century of physics through a successful textbook: Ganot's treatise on physicsbr>English translation)) was a French author and publisher of physics textbooks. Ganot's textbooks, written during the second half of the nineteenth century, made "...a decisive contribution to physics and its teaching on an international scale". His popular ''Treatise on Physics'' (French: ''Traité de Physique'') was translated into several languages. References 19th-century French writers French science writers Textbook writers People from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Church (building)
A church, church building or church house is a building used for Christian worship services and other Christian religious activities. The earliest identified Christian church is a house church founded between 233 and 256. From the 11th through the 14th centuries, there was a wave of church construction in Western Europe. Sometimes, the word ''church'' is used by analogy for the buildings of other religions. ''Church'' is also used to describe the Christian religious community as a whole, or a body or an assembly of Christian believers around the world. In traditional Christian architecture, the plan view of a church often forms a Christian cross; the center aisle and seating representing the vertical beam with the bema and altar forming the horizontal. Towers or domes may inspire contemplation of the heavens. Modern churches have a variety of architectural styles and layouts. Some buildings designed for other purposes have been converted to churches, while many ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bell (instrument)
A bell is a struck idiophone, directly struck idiophone percussion instrument. Most bells have the shape of a hollow cup that when struck vibrates in a single strong strike tone, with its sides forming an efficient resonator. The strike may be made by an internal "clapper" or "uvula", an external hammer, or—in small bells—by a small loose sphere enclosed within the body of the bell (jingle bell). Bells are usually cast from bell metal (a type of bronze) for its resonant properties, but can also be made from other hard materials. This depends on the function. Some small bells such as ornamental bells or cowbells can be made from cast or pressed metal, glass or ceramic, but large bells such as a church, clock and tower bells are normally cast from bell metal. Bells intended to be heard over a wide area can range from a single bell hung in a turret or bell-gable, to a musical ensemble such as an English ring of bells, a carillon or a Russian Russian Orthodox bell ringing, zvon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lowestoft Siren
Lowestoft ( ) is a coastal town and civil parish in the East Suffolk district of Suffolk, England.OS Explorer Map OL40: The Broads: (1:25 000) : . As the most easterly UK settlement, it is north-east of London, north-east of Ipswich and south-east of Norwich, and the main town in its district. The estimated population in the built-up area exceeds 70,000. Its development grew with the fishing industry and as a seaside resort with wide sandy beaches. As fishing declined, oil and gas exploitation in the North Sea in the 1960s took over. While these too have declined, Lowestoft is becoming a regional centre of the renewable energy industry. History Some of the earliest signs of settlement in Britain have been found here. Flint tools discovered in the Pakefield cliffs of south Lowestoft in 2005 allow human habitation of the area to be traced back 700,000 years.S. Parfitt et al. (2006'700,000 years old: found in Pakefield', ''British Archaeology'', January/February 2006. Retri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horn Loudspeaker
A horn loudspeaker is a loudspeaker or loudspeaker element which uses an acoustic horn to increase the overall efficiency of the driving element(s). A common form ''(right)'' consists of a compression driver which produces sound waves with a small metal diaphragm vibrated by an electromagnet, attached to a horn, a flaring duct to conduct the sound waves to the open air. Another type is a woofer driver mounted in a loudspeaker enclosure which is divided by internal partitions to form a zigzag flaring duct which functions as a horn; this type is called a ''folded horn'' speaker. The horn serves to improve the coupling efficiency between the speaker driver and the air. The horn can be thought of as an "acoustic transformer" that provides impedance matching between the relatively dense diaphragm material and the less-dense air. The result is greater acoustic output power from a given driver. The narrow part of the horn next to the driver is called the "throat" and the large part farthe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centrifugal Fan
A centrifugal fan is a mechanical device for moving air or other gases in a direction at an angle to the incoming fluid. Centrifugal fans often contain a ducted housing to direct outgoing air in a specific direction or across a heat sink; such a fan is also called a blower, blower fan, or squirrel-cage fan (because it looks like a hamster wheel). Tiny ones used in computers are sometimes called biscuit blowers. These fans move air from the rotating inlet of the fan to an outlet. They are typically used in ducted applications to either draw air through ductwork/heat exchanger, or push air through similar. impellers. Compared to standard axial fans, they can provide similar air movement from a smaller fan package, and overcome higher resistance in air streams. Centrifugal fans use the kinetic energy of the impellers to move the air stream, which in turn moves against the resistance caused by ducts, dampers and other components. Centrifugal fans displace air radially, changin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Firth Of Clyde
The Firth of Clyde is the mouth of the River Clyde. It is located on the west coast of Scotland and constitutes the deepest coastal waters in the British Isles (it is 164 metres deep at its deepest). The firth is sheltered from the Atlantic Ocean by the Kintyre peninsula, which encloses the outer firth in Argyll and Ayrshire. The Kilbrannan Sound is a large arm of the Firth of Clyde, separating the Kintyre Peninsula from the Isle of Arran. Within the Firth of Clyde is another major island – the Isle of Bute. Given its strategic location at the entrance to the middle and upper Clyde, Bute played a vital naval military role during World War II. Geography At its entrance, the firth is about wide. At one area in its upper reaches, it is joined by Loch Long and the Gare Loch. This area includes the large anchorage off of Greenock that is known as the Tail of the Bank. (The “Bank” is a reference to the shoal, sandbank and shoal that separates the firth from the estuary of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ailsa Craig
Ailsa Craig (; sco, Ailsae Craig; gd, Creag Ealasaid) is an island of in the outer Firth of Clyde, west of mainland Scotland, upon which microgranite has long been quarried to make curling stones. The now-uninhabited island comprises the remains of a magmatic pluton formed during the same period of igneous activity as magmatic rocks on the nearby Isle of Arran. The island, colloquially known as " Paddy's milestone", was a haven for Catholics during the Scottish Reformation in the 16th century, but is today a bird sanctuary, providing a home for huge numbers of gannets and an increasing number of puffins. Etymology An early reference to the rock is made by Sir Donald Monro, Archdeacon of the Isles, who referred to the rock as "Elsay" in the 16th century. The modern name of the island is an anglicisation of the Gaelic, ''Aillse Creag'' meaning "fairy rock". An alternative Gaelic name is ''Creag Ealasaid'' meaning "Elizabeth's rock". The first element, ''Aillse'' may re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trinity House
"Three In One" , formation = , founding_location = Deptford, London, England , status = Royal Charter corporation and registered charity , purpose = Maintenance of lighthouses, buoys and beacons , headquarters = Trinity House, Tower Hill, London, England , region = , membership = , leader_title = Master , leader_name = Anne, Princess Royal , leader_title2 = Deputy Master , leader_name2 = Captain Ian McNaught , revenue = £38,405,000 (2020) , expenses = £46,801,000 (2020) , staff = 312 (2020) , website trinityhouse.co.uk The Corporation of Trinity House of Deptford Strond, also known as Trinity House (and formally as The Master, Wardens and Assistants of the Guild Fraternity or Brotherhood of the most glorious and undivided Trinity and of St Clement in the Parish of Deptford Strond in the County of Kent), is the of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George Henry Slight
George Henry Slight (30 September 1859 – 26 June 1934) was a Scottish engineer who established the Chilean lighthouse service. Early years Slight, the son of George Slight and Elizabeth Marshall, grew up in Edinburgh in an engineering family. After an apprenticeship as a mechanical engineer, he worked on the steamers plying the route between Britain and India. He subsequently worked for several years with Trinity House, which was responsible for the lighthouse service in England and Wales. Chile In 1893 Slight was recruited by the Chilean ambassador in London, Agustin Ross, who had been ordered by the President of Chile, Jorge Montt, to find someone suitable to establish a system of lighthouses in the country. Slight's first task on arrival in Chile was to build a lighthouse on the Evangelistas Islets at the western entrance to the Strait of Magellan in the southern part of the country, which he accomplished when the Evangelistas Lighthouse was completed in 1896. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
