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Sea Mark
A sea mark, also seamark and navigation mark, is a form of aid to navigation and pilotage that identifies the approximate position of a maritime channel, hazard, or administrative area to allow boats, ships, and seaplanes to navigate safely. There are three types of sea mark: beacons (fixed to the seabed or on shore), buoys (consisting of a floating object that is usually anchored to a specific location on the bottom of the sea or to a submerged object) and a type of cairn built on a submerged rock/object, especially in calmer waters. Sea marks are used to indicate channels, dangerous rocks or shoals, mooring positions, areas of speed limits, traffic separation schemes, submerged shipwrecks, and for a variety of other navigational purposes. Some are only intended to be visible in daylight ('' daymarks''), others have some combination of lights, reflectors, fog bells, foghorns, whistles and radar reflectors to make them usable at night and in conditions of reduced visibility. ...
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Fog Bell
A fog bell is a navigation mark used as an audible aid to navigation in seafaring, especially in fog and poor visibility. Floating navigation signs with bells are called bell buoys. On ships, the ship's bell is used for sound signals. Due to more suitable sound generators, but also the development and spread of radar, satellite navigation and electronic charting systems, fog bells have lost their importance for maritime navigation. Maritime marks on land Starting in the 18th century, fog signals were given for seafaring in Europe, initially cannons or guns. In 1766, the first bell for this purpose was installed in Nidingen on the Baltic Sea.Thomas Tag''Fog Bells'' United States Lighthouse Society website. Retrieved September 27, 2021. These were initially rung by hand, which was a chore during prolonged fog, others used mechanisms similar to clockwork that had to be wound periodically. Andrew Morse Jr. eventually developed an "perpetual fog bell" that was used in 1839 at Penobsco ...
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South Korea
South Korea, officially the Republic of Korea (ROK), is a country in East Asia, constituting the southern part of the Korea, Korean Peninsula and sharing a Korean Demilitarized Zone, land border with North Korea. Its western border is formed by the Yellow Sea, while its eastern border is defined by the Sea of Japan. South Korea claims to be the sole legitimate government of the entire peninsula and List of islands of South Korea, adjacent islands. It has a Demographics of South Korea, population of 51.75 million, of which roughly half live in the Seoul Capital Area, the List of metropolitan areas by population, fourth most populous metropolitan area in the world. Other major cities include Incheon, Busan, and Daegu. The Korean Peninsula was inhabited as early as the Lower Paleolithic period. Its Gojoseon, first kingdom was noted in Chinese records in the early 7th century BCE. Following the unification of the Three Kingdoms of Korea into Unified Silla, Silla and Balhae in the ...
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Philippines
The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republika sang Filipinas * ibg, Republika nat Filipinas * ilo, Republika ti Filipinas * ivv, Republika nu Filipinas * pam, Republika ning Filipinas * krj, Republika kang Pilipinas * mdh, Republika nu Pilipinas * mrw, Republika a Pilipinas * pag, Republika na Filipinas * xsb, Republika nin Pilipinas * sgd, Republika nan Pilipinas * tgl, Republika ng Pilipinas * tsg, Republika sin Pilipinas * war, Republika han Pilipinas * yka, Republika si Pilipinas In the recognized optional languages of the Philippines: * es, República de las Filipinas * ar, جمهورية الفلبين, Jumhūriyyat al-Filibbīn is an archipelagic state, archipelagic country in Southeast Asia. It is situated in the western Pacific Ocean and consists of aro ...
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Americas
The Americas, which are sometimes collectively called America, are a landmass comprising the totality of North and South America. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World. Along with their associated islands, the Americas cover 8% of Earth's total surface area and 28.4% of its land area. The topography is dominated by the American Cordillera, a long chain of mountains that runs the length of the west coast. The flatter eastern side of the Americas is dominated by large river basins, such as the Amazon, St. Lawrence River– Great Lakes basin, Mississippi, and La Plata. Since the Americas extend from north to south, the climate and ecology vary widely, from the arctic tundra of Northern Canada, Greenland, and Alaska, to the tropical rain forests in Central America and South America. Humans first settled the Americas from Asia between 42,000 and 17,000 years ago. A second migration of Na-Dene speakers followe ...
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Lateral Mark
A lateral buoy, lateral post or lateral mark, as defined by the International Association of Marine Aids to Navigation and Lighthouse Authorities, is a sea mark used in maritime pilotage to indicate the edge of a channel (geography), channel. Each mark indicates the edge of the safe water channel in terms of port (nautical), port (left-hand) or starboard (right-hand). These directions are relative to the ''direction of buoyage''; this is usually a nominally Source (river or stream), upstream direction. In a river, the direction of buoyage is towards the river's source; in a harbour, the direction of buoyage is into the harbour from the sea. Where there may be doubt, it will be labelled on the appropriate Nautical chart, chart. Often the cardinal mark system is used instead, when confusion about the direction would be common. A vessel heading in the direction of buoyage (e.g. into a harbour) and wishing to keep in the main channel should: * keep port (nautical), port marks to i ...
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Characteristic Light
A light characteristic is all of the properties that make a particular navigational light identifiable. Graphical and textual descriptions of navigational light sequences and colours are displayed on nautical charts and in Light Lists with the chart symbol for a lighthouse, lightvessel, buoy or sea mark with a light on it. Different lights use different colours, frequencies and light patterns, so mariners can identify which light they are seeing. Abbreviations While light characteristics can be described in prose, e.g. "Flashing white every three seconds", lists of lights and navigation chart annotations use abbreviations. The abbreviation notation is slightly different from one light list to another, with dots added or removed, but it usually follows a pattern similar to the following (see the chart to the right for examples). * An abbreviation of the type of light, e.g. "Fl." for flashing, "F." for fixed. * The color of the light, e.g. "W" for white, "G" for green, "R" for red, ...
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Colour
Color (American English) or colour (British English) is the visual perceptual property deriving from the spectrum of light interacting with the photoreceptor cells of the eyes. Color categories and physical specifications of color are associated with objects or materials based on their physical properties such as light absorption, reflection, or emission spectra. By defining a color space, colors can be identified numerically by their coordinates. Because perception of color stems from the varying spectral sensitivity of different types of cone cells in the retina to different parts of the spectrum, colors may be defined and quantified by the degree to which they stimulate these cells. These physical or physiological quantifications of color, however, do not fully explain the psychophysical perception of color appearance. Color science includes the perception of color by the eye and brain, the origin of color in materials, color theory in art, and the physics of elec ...
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Shape
A shape or figure is a graphical representation of an object or its external boundary, outline, or external surface, as opposed to other properties such as color, texture, or material type. A plane shape or plane figure is constrained to lie on a ''plane'', in contrast to ''solid'' 3D shapes. A two-dimensional shape or two-dimensional figure (also: 2D shape or 2D figure) may lie on a more general curved ''surface'' (a non-Euclidean two-dimensional space). Classification of simple shapes Some simple shapes can be put into broad categories. For instance, polygons are classified according to their number of edges as triangles, quadrilaterals, pentagons, etc. Each of these is divided into smaller categories; triangles can be equilateral, isosceles, obtuse, acute, scalene, etc. while quadrilaterals can be rectangles, rhombi, trapezoids, squares, etc. Other common shapes are points, lines, planes, and conic sections such as ellipses, circles, and parabolas. Among the most c ...
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International Association Of Lighthouse Authorities
The International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA), previously known as International Association of Lighthouse Authorities, is an intergovernmental organization founded in 1957 to collect and provide nautical expertise and advice. IALA is also known by its French name of ''Association Internationale de Signalisation Maritime'' (AISM). Background IALA brings together representatives of the aids to navigation services of about 80 countries for technical coordination, information sharing, and coordination of improvements to aids to navigation throughout the world. It was established in 1957 to provide a permanent organization to support the goals of the Technical Lighthouse Conferences, which had been convening since 1929. The General Assembly of IALA meets about every four years. The council of 24 members meets twice a year to oversee the ongoing programs. Four committees maintain work programs established for four year periods: * ENAV&nb ...
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Naval Mine
A naval mine is a self-contained explosive device placed in water to damage or destroy surface ships or submarines. Unlike depth charges, mines are deposited and left to wait until they are triggered by the approach of, or contact with, any vessel or a particular vessel type, akin to anti-infantry vs. anti-vehicle mines. Naval mines can be used offensively, to hamper enemy shipping movements or lock vessels into a harbour; or defensively, to protect friendly vessels and create "safe" zones. Mines allow the minelaying force commander to concentrate warships or defensive assets in mine-free areas giving the adversary three choices: undertake an expensive and time-consuming minesweeping effort, accept the casualties of challenging the minefield, or use the unmined waters where the greatest concentration of enemy firepower will be encountered. Although international law requires signatory nations to declare mined areas, precise locations remain secret; and non-complying individuals ...
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Light Characteristic
A light characteristic is all of the properties that make a particular navigational light identifiable. Graphical and textual descriptions of navigational light sequences and colours are displayed on nautical charts and in Light Lists with the chart symbol for a lighthouse, lightvessel, buoy or sea mark with a light on it. Different lights use different colours, frequencies and light patterns, so mariners can identify which light they are seeing. Abbreviations While light characteristics can be described in prose, e.g. "Flashing white every three seconds", lists of lights and navigation chart annotations use abbreviations. The abbreviation notation is slightly different from one light list to another, with dots added or removed, but it usually follows a pattern similar to the following (see the chart to the right for examples). * An abbreviation of the type of light, e.g. "Fl." for flashing, "F." for fixed. * The color of the light, e.g. "W" for white, "G" for green, "R" for re ...
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