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Lanby Buoy
LANBY, a contraction of Large Automatic Navigation BuoY, was a type of floating navigational aid designed to replace lightships. Now obsolete, they were originally made in the USA by General Dynamics and adapted by Hawker Siddeley Dynamics for use in British waters in the early 1970s. They consisted of a circular hull with a raised central structure containing a 360° light and foghorn, and sometimes also a radio beacon. They were monitored from onshore and designed to run for extended periods without repair. Their running costs were estimated to be as low as 10% of those of lightships. Equipment UK models followed the General Dynamics design: Power was supplied by three diesel alternators of 230 V, individually rated at 5 kW continuous output. These were each run in a 72-hour operational cycle of 24 hours under power, followed by 48 at rest. Maintenance and refuelling was at six-month intervals. A static rectifier provided continuous power at 28 V DC, cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultra High Frequency
Ultra high frequency (UHF) is the ITU designation for radio frequency, radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one tenth of a meter (one decimeter). Radio waves with frequencies above the UHF band fall into the super-high frequency (SHF) or microwave frequency range. Lower frequency signals fall into the VHF (very high frequency) or lower bands. UHF radio waves propagate mainly by Line-of-sight propagation, line of sight; they are blocked by hills and large buildings although the transmission through building walls is strong enough for indoor reception. They are used for UHF television broadcasting, television broadcasting, cell phones, satellite communication including GPS, personal radio services including Wi-Fi and Bluetooth, walkie-talkies, cordless phones, satellite phones, and numerous other applications. The Institute of Electrical and Electronics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nautical Terminology
This glossary of nautical terms is an alphabetical listing of terms and expressions connected with ships, shipping, seamanship and navigation on water (mostly though not necessarily on the sea). Some remain current, while many date from the 17th to 19th centuries. The word nautical derives from the Latin ''nauticus'', from Greek ''nautikos'', from ''nautēs'': "sailor", from ''naus'': "ship". Further information on nautical terminology may also be found at Nautical metaphors in English, and additional military terms are listed in the Multiservice tactical brevity code article. Terms used in other fields associated with bodies of water can be found at Glossary of fishery terms, Glossary of underwater diving terminology, Glossary of rowing terms, and Glossary of meteorology. This glossary is split into two articles: * terms starting with the letters A to L are at Glossary of nautical terms (A-L) * terms starting with the letters M to Z are at Glossary of nautical terms (M-Z). __ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estuary
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environments and are an example of an ecotone. Estuaries are subject both to marine influences such as tides, waves, and the influx of saline water, and to fluvial influences such as flows of freshwater and sediment. The mixing of seawater and freshwater provides high levels of nutrients both in the water column and in sediment, making estuaries among the most productive natural habitats in the world. Most existing estuaries formed during the Holocene epoch with the flooding of river-eroded or glacially scoured valleys when the sea level began to rise about 10,000–12,000 years ago. Estuaries are typically classified according to their geomorphological features or to water-circulation patterns. They can have many different names, such as bays, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
River Mersey
The River Mersey () is in North West England. Its name derives from Old English and means "boundary river", possibly referring to its having been a border between the ancient kingdoms of Mercia and Northumbria. For centuries it has formed part of the boundary between the Historic counties of England, historic counties of Lancashire and Cheshire. The Mersey starts at the confluence of the River Tame, Greater Manchester, River Tame and River Goyt in Stockport. It flows westwards through south Manchester, then into the Manchester Ship Canal at Irlam, becoming a part of the canal and maintaining its water levels. After it exits the canal, flowing towards Warrington where it widens. It then narrows as it passes between Runcorn and Widnes. From Runcorn the river widens into a large estuary, which is across at its widest point near Ellesmere Port. The course of the river then turns northwards as the estuary narrows between Liverpool and Birkenhead on the Wirral Peninsula to the west ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calshot Spit
Calshot Spit is a one-mile long sand and slate, shingle bank, near the village of Calshot, located on the southern bank of the open end of Southampton Water, on the south coast of England.OS Explorer Map, New Forest, Scale: 1:25 000.Publisher: Ordnance Survey B4 edition (2013). At the end of the Spit (landform), spit are Calshot Castle (built by King Henry VIII of England, Henry VIII), an RNLI Lifeboat (rescue), lifeboat, an National Coastwatch Institution, NCI station, several slipways, a former Royal Navy and Royal Air Force flying boat station and Calshot Activities Centre. The neck of the spit is owned by New Forest District Council while the end of the spit is owned by the Crown Estate which leases it to Hampshire County Council. History The castle is a low, circular, stone structure and was armed with large muzzle-loading guns. Its purpose, when it was built in 1539, was to protect access to the important harbour at Southampton from seaborne attack, by France or Spain f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Sovereign Lighthouse
Royal Sovereign lighthouse, located offshore from Eastbourne, is a decommissioned lighthouse marking the Royal Sovereign shoal, a sandbank named after HMS Sovereign of the Seas, HMS ''Royal Sovereign''. Its distinctive shape is easily recognised as it comprises a large platform (which functions as a helicopter deck) supported by a single pillar rising out of the water. Originally, the platform was manned by three full-time keepers, accommodation being contained in the 'cabin section' immediately below the platform. Additional accommodation was provided for up to four visiting maintenance workers. Construction and installation The lighthouse replaced a Lightvessel, lightship that had marked the Royal Sovereign Shoal since 1875. The structure was built, in two parts, on Newhaven, East Sussex, Newhaven beach, and put into position in 1970. First, the base and attached column were floated out to the shoal, where the hollow base was flooded and allowed to sink into position. Then t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parabolic Aluminized Reflector
A parabolic aluminized reflector lamp (PAR lamp or simply PAR) is a type of electric lamp that is widely used in commercial, residential, and transportation illumination. It produces a highly directional beam. Usage includes theatrical lighting, locomotive headlamps, aircraft landing lights, and residential and commercial recessed lights ("cans" in the United States). Many PAR lamps are of the sealed beam variety, with a parabolic reflector, one or more filaments, and a glass or plastic lens sealed permanently together as a unit. Originally introduced for road vehicle headlamp service, sealed beams have since been applied elsewhere. Halogen sealed beam lamps incorporate a halogen lamp within a quartz or hard glass envelope. Construction A PAR lamp consists of a light source, with lens and a parabolic reflector with a smooth aluminium surface determining the spread of the beam. The most common sealed beam type combines these three elements into an integral unit. The light ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telemetry
Telemetry is the in situ data collection, collection of measurements or other data at remote points and their automatic data transmission, transmission to receiving equipment (telecommunication) for monitoring. The word is derived from the Greek language, Greek roots ''tele'', "remote", and ''metron'', "measure". Systems that need external instructions and data to operate require the counterpart of telemetry, telecommand. Although the term commonly refers to wireless data transfer mechanisms (e.g., using radio, ultrasonic, or Infrared#Communications, infrared systems), it also encompasses data transferred over other media such as a telephone or computer network, optical link or other wired communications like power line carriers. Many modern telemetry systems take advantage of the low cost and ubiquity of GSM networks by using SMS to receive and transmit telemetry data. A ''telemeter'' is a physical device used in telemetry. It consists of a sensor, a transmission path, and a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flashtube
A flashtube (flashlamp) is an electric arc lamp designed to produce extremely intense, incoherent, full-spectrum white light for a very short time. A flashtube is a glass tube with an electrode at each end and is filled with a gas that, when triggered, ionizes and conducts a high-voltage pulse to make light. Flashtubes are used most in photography; they also are used in science, medicine, industry, and entertainment. Construction The lamp comprises a hermetically sealed glass tube, which is filled with a noble gas, usually xenon, and electrodes to carry electrical current to the gas. Additionally, a high voltage power source is necessary to energize the gas as a trigger event. A charged capacitor is usually used to supply energy for the flash, so as to allow very speedy delivery of very high electrical current when the lamp is triggered. Glass envelopes The glass envelope is most commonly a thin tube, often made of fused quartz, borosilicate or Pyrex, which may be straight, o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lightvessel
A lightvessel, or lightship, is a ship that acts as a lighthouse. They are used in waters that are too deep or otherwise unsuitable for lighthouse construction. Although some records exist of fire beacons being placed on ships in Roman times, the first modern lightvessel was off the Nore sandbank at the mouth of the River Thames in England, placed there by its inventor Robert Hamblin in 1734. The type has become largely obsolete; lighthouses replaced some stations as the construction techniques for lighthouses advanced, while large, automated buoys replaced others. Construction A crucial element of lightvessel design is the mounting of a light on a sufficiently tall mast. Initially, it consisted of oil lamps that could be run up the mast and lowered for servicing. Later vessels carried fixed lamps which were serviced in place. Fresnel lenses were used as they became available, and many vessels housed them in small versions of the lanterns used in lighthouses. Some lightship ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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