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Mafuta (ship)
''Mafuta'' is a diamond-mining ship owned and operated by De Beers in the western coast of South Africa. Built in 1983 as ''Dock Express 20'' for Dock Express Shipping (later Dockwise), the semisubmersible, multirole, heavy lift vessel, heavy-lift vessel was converted to the world's largest cable layer in 1993.Brown, NicholasDutch ships lay Tyco cable Seacoastonline.com, 21 June 2002. Retrieved 2011-08-30 In 2005, she was purchased by De Beers, and converted to a subsea diamond-mining ship by A&P Tyne over the course of 11 months. The ship's new name, ''Peace in Africa'', may have implied that it was providing an alternative to blood diamonds.A&P wins Conversion Contract MarineLink.com, 20 July 2005. Retrieved 2011-08-30 In 2013, still under ownership of De Be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dock Express Shipping
Dockwise was a Netherlands-based holding company in the marine transport industry. It was acquired by Boskalis in 2013 and was merged into the Boskalis brand name in 2018. History Dockwise was formed in September 1993 by the merger of two complementary companies, Wijsmuller Transport (a division of Heerema Marine Contractors, Heerema) and Dock Express Shipping (a division of Vopak, Royal Vopak), becoming the world's largest seagoing heavy-transport shipping company. The combined company operated from a new headquarters in Meer (Hoogstraten), Belgium. Wijsmuller brought a fleet of seven semisubmersible vessels (Mighty Servant 1, ''Mighty Servant'' 1, Mighty Servant 2, ''Mighty Servant'' 2, Mighty Servant 3, ''Mighty Servant'' 3, and ''Super Servant'' 3, 4, MV Bali Sea, 5, and 6) and four dock-type vessels (''Dock Express'' 10, 11, 12, and 20). In 2001, Offshore Heavy Transport ASA joined the company, adding two heavy-transport vessels, and . In November 2010, to serve the emergin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cable Layer
A cable layer or cable ship is a deep-sea ship, vessel designed and used to lay underwater cables Submarine communications cable, for telecommunications, Submarine power cable, for electric power transmission, military, or other purposes. Cable ships are distinguished by large cable sheaves for guiding cable over Bow (watercraft), bow or stern or both. Bow sheaves, some very large, were characteristic of all cable ships in the past, but newer ships are tending toward having stern sheaves only, as seen in the photo of CS ''Cable Innovator'' at the Port of Astoria on this page. The names of cable ships are often preceded by "C.S." as in CS ''Long Lines''. The first transatlantic telegraph cable was laid by cable layers in 1857 to 1858. It briefly enabled telecommunication between Europe and North America before misuse resulted in failure of the line. In 1866 the successfully laid two transatlantic cables, securing future communication between the continents. Modern cable ships ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Diesel Engine
Marine propulsion is the mechanism or system used to generate thrust to move a watercraft through water. While paddles and sails are still used on some smaller boats, most modern ships are propelled by mechanical systems consisting of an electric motor or internal combustion engine driving a propeller, or less frequently, in pump-jets, an impeller. Marine engineering is the discipline concerned with the engineering design process of marine propulsion systems. Human-powered paddles and oars, and later, sails were the first forms of marine propulsion. Rowed galleys, some equipped with sail, played an important early role in early human seafaring and warfare. The first advanced mechanical means of marine propulsion was the marine steam engine, introduced in the early 19th century. During the 20th century it was replaced by two-stroke or four-stroke diesel engines, outboard motors, and gas turbine engines on faster ships. Marine nuclear reactors, which appeared in the 1950s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Four Stroke Diesel Engine
A four-stroke (also four-cycle) engine is an internal combustion (IC) engine in which the piston completes four separate strokes while turning the crankshaft. A stroke refers to the full travel of the piston along the cylinder, in either direction. The four separate strokes are termed: #Intake: Also known as induction or suction. This stroke of the piston begins at top dead center (T.D.C.) and ends at bottom dead center (B.D.C.). In this stroke the intake valve must be in the open position while the piston pulls an air-fuel mixture into the cylinder by producing a partial vacuum (negative pressure) in the cylinder through its downward motion. #Compression: This stroke begins at B.D.C, or just at the end of the suction stroke, and ends at T.D.C. In this stroke the piston compresses the air-fuel mixture in preparation for ignition during the power stroke (below). Both the intake and exhaust valves are closed during this stage. #Combustion: Also known as power or ignition. This is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sperm Whale
The sperm whale or cachalot (''Physeter macrocephalus'') is the largest of the toothed whales and the largest toothed predator. It is the only living member of the Genus (biology), genus ''Physeter'' and one of three extant species in the sperm whale superfamily Physeteroidea, along with the pygmy sperm whale and dwarf sperm whale of the genus ''Kogia''. The sperm whale is a pelagic mammal with a worldwide range, and will migrate seasonally for feeding and breeding. Females and young males live together in groups, while mature males (bulls) live solitary lives outside of the mating season. The females cooperate to protect and Lactation, nurse their young. Females give birth every four to twenty years, and care for the calves for more than a decade. A mature, healthy sperm whale has no natural predators, although calves and weakened adults are sometimes killed by Cetacea#Social relations, pods of killer whales (orcas). Mature males average in length, with the head represent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carrying Capacity
The carrying capacity of an ecosystem is the maximum population size of a biological species that can be sustained by that specific environment, given the food, habitat, water, and other resources available. The carrying capacity is defined as the environment's maximal load, which in population ecology corresponds to the population equilibrium, when the number of deaths in a population equals the number of births (as well as immigration and emigration). Carrying capacity of the environment implies that the resources extraction is not above the rate of regeneration of the resources and the wastes generated are within the assimilating capacity of the environment. The effect of carrying capacity on population dynamics is modelled with a logistic function. Carrying capacity is applied to the maximum population an environment can support in ecology, agriculture and fisheries. The term carrying capacity had been applied to a few different processes in the past before finally being appl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Net Tonnage
Net tonnage (NT, N.T. or nt) is a dimensionless index calculated from the total moulded volume of the ship's cargo spaces by using a mathematical formula. Defined in ''The International Convention on Tonnage Measurement of Ships'' that was adopted by the International Maritime Organization in 1969, the net tonnage replaced the earlier net register tonnage (NRT) which denoted the volume of the ship's revenue-earning spaces in "register tons", units of volume equal to . Net tonnage is used to calculate the port duties and should not be taken as less than 30 per cent of the ship's gross tonnage.International Convention on Tonnage Measurement of Ships . International Maritime Organization (IMO). Net tonnage is not a measure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gross Tonnage
Gross tonnage (GT, G.T. or gt) is a nonlinear measure of a ship's overall internal volume. Gross tonnage is different from gross register tonnage. Neither gross tonnage nor gross register tonnage should be confused with measures of mass or weight such as deadweight tonnage or displacement. Gross tonnage, along with net tonnage, was defined by the ''International Convention on Tonnage Measurement of Ships, 1969'', adopted by the International Maritime Organization (IMO) in 1969, and came into force on 18 July 1982. These two measurements replaced gross register tonnage (GRT) and net register tonnage (NRT). Gross tonnage is calculated based on "the moulded volume of all enclosed spaces of the ship" and is used to determine things such as a ship's manning regulations, safety rules, registration fees, and port dues, whereas the older gross register tonnage is a measure of the volume of only certain enclosed spaces. History The International Convention on Tonnage Measurement of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moulded Depth
A hull is the watertight body of a ship, boat, submarine, or flying boat. The hull may open at the top (such as a dinghy), or it may be fully or partially covered with a deck. Atop the deck may be a deckhouse and other superstructures, such as a funnel, derrick, or Mast (sailing), mast. The line where the hull meets the water surface is called the waterline. General features There is a wide variety of hull types that are chosen for suitability for different usages, the hull shape being dependent upon the needs of the design. Shapes range from a nearly perfect box, in the case of scow barges, to a needle-sharp surface of revolution in the case of a racing multihull sailboat. The shape is chosen to strike a balance between cost, hydrostatic considerations (accommodation, load carrying, and stability), hydrodynamics (speed, power requirements, and motion and behavior in a seaway) and special considerations for the ship's role, such as the rounded bow of an icebreaker or the flat bot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beam (ship)
The beam of a ship is its width at its widest point. The maximum beam (BMAX) is the distance between planes passing through the outer sides of the ship, beam of the hull (BH) only includes permanently fixed parts of the hull, and beam at waterline (BWL) is the maximum width where the hull intersects the surface of the water. Generally speaking, the wider the beam of a ship (or boat), the more initial stability it has, at the expense of secondary stability in the event of a capsize, where more energy is required to right the vessel from its inverted position. A ship that heels on her ''beam ends'' has her deck beams nearly vertical. Typical values Typical length-to-beam ratios (aspect ratios) for small sailboats are from 2:1 (dinghies to trailerable sailboats around ) to 5:1 (racing sailboats over ). Large ships have widely varying beam ratios, some as large as 20:1. Rowing shells designed for flatwater racing may have length to beam ratios as high as 30:1, while a coracle ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Length Overall
Length overall (LOA, o/a, o.a. or oa) is the maximum length of a vessel's hull measured parallel to the waterline. This length is important while docking the ship. It is the most commonly used way of expressing the size of a ship, and is also used for calculating the cost of a marina berth (for example, £2.50 per metre LOA). LOA is usually measured on the hull alone. For sailing ships, this may ''exclude'' the bowsprit and other fittings added to the hull. This is how some racing boats and tall ships use the term LOA. However, other sources may include bowsprits in LOA. Confusingly, LOA has different meanings. "Sparred length", "Total length including bowsprit", "Mooring length" and "LOA including bowsprit" are other expressions that might indicate the full length of a sailing ship. LOD Often used to distinguish between the length of a vessel including projections (e.g. bow sprits, etc.) from the length of the hull itself, the Length on Deck or LOD is often reported. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ceremonial Ship Launching
Ceremonial ship launching involves the performing of ceremonies associated with the process of transferring a vessel to the water. It is a nautical tradition in many cultures, dating back millennia, to accompany the physical process with ceremonies which have been observed as public celebration and a solemn blessing, usually but not always, in association with the launch itself. Ship launching imposes stresses on the ship not met during normal operation and in addition to the size and weight of the vessel represents a considerable engineering challenge as well as a public spectacle. The process also involves Sailors' superstitions, many traditions intended to invite good luck, such as baptism#Boats and ships, christening by breaking a sacrificial bottle of champagne over the bow (ship), bow as the ship is named aloud and launched. Methods There are three principal methods of conveying a new ship from building site to water, only two of which are called "launching". The ol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
