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Mouthpiece Retaining Strap
A scuba set, originally just scuba, is any breathing apparatus that is entirely carried by an underwater diver and provides the diver with breathing gas at the ambient pressure. ''Scuba'' is an anacronym for self-contained underwater breathing apparatus. Although strictly speaking the scuba set is only the diving equipment that is required for providing breathing gas to the diver, general usage includes the harness or rigging by which it is carried and those accessories which are integral parts of the harness and breathing apparatus assembly, such as a jacket or wing style buoyancy compensator and instruments mounted in a combined housing with the pressure gauge. In the looser sense, scuba set has been used to refer to all the diving equipment used by the scuba diver, though this would more commonly and accurately be termed scuba equipment or scuba gear. Scuba is overwhelmingly the most common underwater breathing system used by recreational divers and is also used in profess ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Underwater Diving
Underwater diving, as a human activity, is the practice of descending below the water's surface to interact with the environment. It is also often referred to as diving (other), diving, an ambiguous term with several possible meanings, depending on context. Immersion in water and exposure to high ambient pressure have Physiology, physiological effects that limit the depths and duration possible in ambient pressure diving. Humans are not physiologically and anatomically well-adapted to the environmental conditions of diving, and various equipment has been developed to extend the depth and duration of human dives, and allow different types of work to be done. In ambient pressure diving, the diver is directly exposed to the pressure of the surrounding water. The ambient pressure diver may dive on breath-hold (freediving) or use breathing apparatus for scuba diving or surface-supplied diving, and the saturation diving technique reduces the risk of decompression sickness ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lambertsen Amphibious Respiratory Unit
The Lambertsen Amphibious Respiratory Unit (LARU) is an early model of closed circuit oxygen rebreather used by military frogmen. Christian J. Lambertsen designed a series of them in the US in 1940 (patent filing date: 16 Dec 1940) and in 1944 (issue date: 2 May 1944). Etymology The LARU is what the initials SCUBA (Self-Contained Underwater Breathing Apparatus) originally meant; Lambertsen changed his invention's name to SCUBA in 1952; but later "SCUBA", gradually changing to "scuba", came to mean (first in the USA) any self-contained underwater breathing apparatus. (Modern diving regulator technology was invented by Émile Gagnan and Jacques-Yves Cousteau in 1943 and was not related to rebreathers; nowadays the word SCUBA is largely used to mean Gagnan's and Cousteau's invention and its derivatives.) History Lambertsen designed the LARU while a medical student and demonstrated the LARU to the Office of Strategic Services (OSS) (after already being rejected by the U.S. Navy) in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Filter
A particulate air filter is a device composed of fibrous, or porous materials which removes particulates such as smoke, dust, pollen, mold, viruses and bacteria from the air. Filters containing an adsorbent or catalyst such as charcoal (carbon) may also remove odors and gaseous pollutants such as volatile organic compounds or ozone. Air filters are used in applications where air quality is important, notably in building ventilation systems and in engines. Some buildings, as well as aircraft and other human-made environments (e.g., satellites, and Space Shuttles) use foam, pleated paper, or spun fiberglass filter elements. Another method, air ionizers, use fibers or elements with a static electric charge, which attract dust particles. The air intakes of internal combustion engines and air compressors tend to use either paper, foam, or cotton filters. Oil bath filters have fallen out of favour aside from niche uses. The technology of air intake filters of gas turbines has impr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Free-diving
Freediving, free-diving, free diving, breath-hold diving, or skin diving, is a mode of underwater diving that relies on apnea, breath-holding until resurfacing rather than the use of breathing apparatus such as scuba set, scuba gear. Besides the limits of Apnea, breath-hold, immersion in water and exposure to high ambient pressure also have physiological effects that limit the depths and duration possible in freediving. Examples of freediving activities are artisanal fishing, traditional fishing techniques, competitive and non-competitive freediving, competitive and non-competitive spearfishing and freediving photography, synchronised swimming, underwater football, underwater rugby, underwater hockey, underwater target shooting and snorkeling. There are also a range of "competitive apnea" disciplines; in which competitors attempt to attain great depths, times, or distances on a single breath. Historically, the term ''free diving'' was also used to refer to scuba diving, due to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Underwater
An underwater environment is a environment of, and immersed in, liquid water in a natural or artificial feature (called a Water, body of water), such as an ocean, sea, lake, pond, reservoir, river, canal, or aquifer. Some characteristics of the underwater environment are universal, but many depend on the local situation. Liquid water has been present on Earth for most of the History of Earth, history of the planet. The underwater environment is thought to be the place of the origin of life on Earth, and it remains the ecological region most critical to the support of life and the natural habitat of the majority of living organisms. Several branches of science are dedicated to the study of this environment or specific parts or aspects of it. A number of human activities are conducted in the more accessible parts of the underwater environment. These include research, underwater diving for work or recreation, and underwater warfare with submarines. It is hostile to humans in many ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Welsh Language
Welsh ( or ) is a Celtic languages, Celtic language of the Brittonic languages, Brittonic subgroup that is native to the Welsh people. Welsh is spoken natively in Wales by about 18% of the population, by some in England, and in (the Welsh colony in Chubut Province, Argentina). It is spoken by smaller numbers of people in Canada and the United States descended from Welsh immigrants, within their households (especially in Nova Scotia). Historically, it has also been known in English as "British", "Cambrian", "Cambric" and "Cymric". The Welsh Language (Wales) Measure 2011 gave the Welsh language official status in Wales. Welsh and English are ''de jure'' official languages of the Senedd (the Welsh parliament), with Welsh being the only ''de jure'' official language in any part of the United Kingdom, with English being merely ''de facto'' official. According to the 2021 United Kingdom census, 2021 census, the Welsh-speaking population of Wales aged three or older was 538,300 ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar
Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track aircraft, ships, spacecraft, guided missiles, motor vehicles, map weather formations, and terrain. The term ''RADAR'' was coined in 1940 by the United States Navy as an acronym for "radio detection and ranging". The term ''radar'' has since entered English and other languages as an anacronym, a common noun, losing all capitalization. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwave domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the objects. Radio waves (pulsed or continuous) from the transmitter reflect off the objects and return to the receiver, giving ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
English-speaking World
The English-speaking world comprises the 88 countries and territories in which English language, English is an official, administrative, or cultural language. In the early 2000s, between one and two billion people spoke English, making it the List of languages by total number of speakers, largest language by number of speakers, the List of languages by number of native speakers, third largest language by number of native speakers and the most widespread language geographically. The countries in which English is the native language of most people are sometimes termed the Anglosphere. Speakers of English are called Anglophones. History of Anglo-Saxon England, Early Medieval England was the birthplace of the English language; the Modern English, modern form of the language has been spread around the world since the 17th century, first by the worldwide influence of England and later the United Kingdom, and then by that of the United States. Through all types of printed and electron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
