Q-Max
Q-Max is a type of ship a membrane type liquefied natural gas carrier. In the name Q-Max, "Q" stands for Qatar and "Max" for the maximum size of ship able to dock at the LNG terminals in Qatar. Ships of this type are the largest LNG carriers in the world. A ship of Q-Max size is 345 metres long and measures 53.8 metres wide and 34.7 metres high, with a draft of 12 metres. It has an LNG capacity of 266,000 cubic metres, equal to 161,994,000 cubic metres of natural gas, it is propelled by two slow speed diesel engines burning HFO, which are claimed to be more efficient and environmentally friendly than traditional steam turbines. In case of engine failure, the failed engine can be de-coupled allowing the ship to maintain a speed of 14 knots. Q-Max vessels are equipped with an on-board re-liquefaction system to handle the boil-off gas, liquefy it and return the LNG to the cargo tanks; the on-board re-liquefaction system allows a reduction of LNG losses, which produces economic and environmental benefits.
Overall, it is estimated that Q-Max carriers have about 40% lower energy requirements and carbon emissions than conventional LNG carriers. The quoted estimates do however ignore the additional fuel used to re-liquify boil off gas rather than burn the gas for fuel; the ships run on Heavy fuel oil, but the Rasheeda was retrofitted with gas-burning ability in 2015. Q-Max LNG carriers were ordered in 2005, they are built by Daewoo Shipbuilding & Marine Engineering. The installed Boil Off Gas re-liquefaction system is developed and delivered by Cryostar, approved and certified by Lloyds Register; the first Q-Max LNG carrier was floated out of dry-dock in November 2007. The naming ceremony was held on 11 July 2008 at Samsung Heavy Industries' shipyard on Geoje Island, South Korea. Known before its naming ceremony as Hull 1675, the ship was named Mozah by Her Highness Sheikha Mozah Nasser al-Misnad. Mozah was delivered on 29 September 2008, it is classed by Lloyd's Register. The first trip by a Q-Max tanker was completed by Mozah itself on 11 January 2009, when the tanker delivered 266,000 cubic metres of LNG to the Port of Bilbao BBG Terminal.
Days before, the vessel had transited the Suez Canal for the first time. Q-Max LNG carriers are operated by the STASCo (Shell International Trading and Shipping Company, London part of Shell International, they are owned by Qatar Gas Transport Company and they are chartered to Qatar's LNG producers Qatargas and RasGas. In total, contracts were signed for the construction of 14 Q-Max vessels. Fourteen sister vessels are in service named: Mozah, Al Mayeda, Mekaines, Al Mafyar, Umm Slal, Bu Samra, Al Ghuwairiya, Lijmiliya, Al Samriya, Al Dafna, Zarga and Rasheeda. All 14 Q-Max ships were delivered in 2008 through 2010. Q-Flex Ras Laffan Industrial City Tanker ships Ship sizes
Panama Canal
The Panama Canal is an artificial 82 km waterway in Panama that connects the Atlantic Ocean with the Pacific Ocean. The canal is a conduit for maritime trade. Canal locks are at each end to lift ships up to Gatun Lake, an artificial lake created to reduce the amount of excavation work required for the canal, 26 m above sea level, lower the ships at the other end; the original locks are 34 m wide. A third, wider lane of locks was constructed between September 2007 and May 2016; the expanded canal began commercial operation on June 26, 2016. The new locks allow transit of larger, post-Panamax ships, capable of handling more cargo. France began work on the canal in 1881, but stopped due to engineering problems and a high worker mortality rate; the United States took over the project in 1904 and opened the canal on August 15, 1914. One of the largest and most difficult engineering projects undertaken, the Panama Canal shortcut reduced the time for ships to travel between the Atlantic and Pacific Oceans, enabling them to avoid the lengthy, hazardous Cape Horn route around the southernmost tip of South America via the Drake Passage or Strait of Magellan.
Colombia and the United States controlled the territory surrounding the canal during construction. The US continued to control the canal and surrounding Panama Canal Zone until the 1977 Torrijos–Carter Treaties provided for handover to Panama. After a period of joint American–Panamanian control, in 1999, the canal was taken over by the Panamanian government, it is now operated by the government-owned Panama Canal Authority. Annual traffic has risen from about 1,000 ships in 1914, when the canal opened, to 14,702 vessels in 2008, for a total of 333.7 million Panama Canal/Universal Measurement System tons. By 2012, more than 815,000 vessels had passed through the canal, it takes 11.38 hours to pass through the Panama Canal. The American Society of Civil Engineers has ranked the Panama Canal one of the seven wonders of the modern world; the earliest mention of a canal across the Isthmus of Panama occurred in 1534, when Charles V, Holy Roman Emperor and King of Spain, ordered a survey for a route through the Americas that would ease the voyage for ships traveling between Spain and Peru.
Such a route would have given the Spanish a military advantage over the Portuguese. In 1668, the English physician and philosopher Sir Thomas Browne speculated in his encyclopaedic endeavour Pseudodoxia Epidemica - "some Isthmus have been eat through by the Sea, others cut by the spade: And if policy would permit, that of Panama in America were most worthy the attempt: it being but few miles over, would open a shorter cut unto the East Indies and China". In 1788, American Thomas Jefferson Minister to France, suggested that the Spanish should build the canal since it would be a less treacherous route for ships than going around the southern tip of South America, that tropical ocean currents would widen the canal thereafter. During an expedition from 1788 to 1793, Alessandro Malaspina outlined plans for its construction. Given the strategic location of Panama and the potential offered by its narrow isthmus separating two great oceans, other trade links in the area were attempted over the years.
The ill-fated Darien scheme was launched by the Kingdom of Scotland in 1698 to set up an overland trade route. Inhospitable conditions thwarted the effort and it was abandoned in April 1700. Numerous canals were built in other countries in the late early 19th centuries; the success of the Erie Canal in the United States in the 1820s and the collapse of the Spanish Empire in Latin America led to a surge of American interest in building an inter-oceanic canal. Beginning in 1826, US officials began negotiations with Gran Colombia, hoping to gain a concession for the building of a canal. Jealous of their newly obtained independence and fearing that they would be dominated by an American presence, the president Simón Bolívar and New Granada officials declined American offers; the new nation was politically unstable, Panama rebelled several times during the 19th century. Another effort was made in 1843. According to the New York Daily Tribune, August 24, 1843, a contract was entered into by Barings of London and the Republic of New Granada for the construction of a canal across the Isthmus of Darien.
They referred to it as the Atlantic and Pacific Canal, it was a wholly British endeavor. It was expected to be completed in five years. At nearly the same time, other ideas were floated, including a canal across Mexico's Isthmus of Tehuantepec. Nothing came of that plan, either. In 1846, the Mallarino–Bidlack Treaty, negotiated between the US and New Granada, granted the United States transit rights and the right to intervene militarily in the isthmus. In 1848, the discovery of gold in California, on the West Coast of the United States, created great interest in a crossing between the Atlantic and Pacific oceans. William H. Aspinwall, the man who won the federal subsidy for the building and operating the Pacific mail steamships at around the same time, benefited from this discovery. Aspinwall's route included steamship legs from New York City to Panama and from Panama to California, with an overland portage through Panama; the route between California and Panama was soon traveled, as it provided one of the fastest links between San Francisco and the East Coast cities, about 40 days' transit in total.
Nearly all the gold, shipped out of California went by the fast Panama route. Several new and larger paddle steamers were soon plying
Great Britain
Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of 209,331 km2, it is the largest of the British Isles, the largest European island, the ninth-largest island in the world. In 2011, Great Britain had a population of about 61 million people, making it the world's third-most populous island after Java in Indonesia and Honshu in Japan; the island of Ireland is situated to the west of Great Britain, together these islands, along with over 1,000 smaller surrounding islands, form the British Isles archipelago. The island is dominated by a maritime climate with quite narrow temperature differences between seasons. Politically, Great Britain is part of the United Kingdom of Great Britain and Northern Ireland, constitutes most of its territory. Most of England and Wales are on the island; the term "Great Britain" is used to include the whole of England and Wales including their component adjoining islands. A single Kingdom of Great Britain resulted from the union of the Kingdom of England and the Kingdom of Scotland by the 1707 Acts of Union.
In 1801, Great Britain united with the neighbouring Kingdom of Ireland, forming the United Kingdom of Great Britain and Ireland, renamed the "United Kingdom of Great Britain and Northern Ireland" after the Irish Free State seceded in 1922. The archipelago has been referred to by a single name for over 2000 years: the term'British Isles' derives from terms used by classical geographers to describe this island group. By 50 BC Greek geographers were using equivalents of Prettanikē as a collective name for the British Isles. However, with the Roman conquest of Britain the Latin term Britannia was used for the island of Great Britain, Roman-occupied Britain south of Caledonia; the earliest known name for Great Britain is Albion or insula Albionum, from either the Latin albus meaning "white" or the "island of the Albiones". The oldest mention of terms related to Great Britain was by Aristotle, or by Pseudo-Aristotle, in his text On the Universe, Vol. III. To quote his works, "There are two large islands in it, called the British Isles and Ierne".
Pliny the Elder in his Natural History records of Great Britain: "Its former name was Albion. Old French Bretaigne and Middle English Bretayne, Breteyne; the French form replaced the Old English Breoton, Bryten, Breten. Britannia was used by the Romans from the 1st century BC for the British Isles taken together, it is derived from the travel writings of the Pytheas around 320 BC, which described various islands in the North Atlantic as far north as Thule. Marcian of Heraclea, in his Periplus maris exteri, described the island group as αἱ Πρεττανικαὶ νῆσοι; the peoples of these islands of Prettanike were called the Priteni or Pretani. Priteni is the source of the Welsh language term Prydain, which has the same source as the Goidelic term Cruithne used to refer to the early Brythonic-speaking inhabitants of Ireland; the latter were called Picts or Caledonians by the Romans. Greek historians Diodorus of Sicily and Strabo preserved variants of Prettanike from the work of Greek explorer Pytheas of Massalia, who travelled from his home in Hellenistic southern Gaul to Britain in the 4th century BC.
The term used by Pytheas may derive from a Celtic word meaning "the painted ones" or "the tattooed folk" in reference to body decorations. The Greco-Egyptian scientist Ptolemy referred to the larger island as great Britain and to Ireland as little Britain in his work Almagest. In his work, Geography, he gave the islands the names Alwion and Mona, suggesting these may have been the names of the individual islands not known to him at the time of writing Almagest; the name Albion appears to have fallen out of use sometime after the Roman conquest of Britain, after which Britain became the more commonplace name for the island. After the Anglo-Saxon period, Britain was used as a historical term only. Geoffrey of Monmouth in his pseudohistorical Historia Regum Britanniae refers to the island as Britannia major, to distinguish it from Britannia minor, the continental region which approximates to modern Brittany, settled in the fifth and sixth centuries by migrants from Britain; the term Great Britain was first used in 1474, in the instrument drawing up the proposal for a marriage between Cecily the daughter of Edward IV of England, James the son of James III of Scotland, which described it as "this Nobill Isle, callit Gret Britanee".
It was used again in 1604, when King James VI and I styled himself "King of Great Brittaine and Ireland". Great Britain refers geographically to the island of Great Britain, it is often used to refer politically to the whole of England and Wales, including their smaller off shore islands. While it is sometimes used to refer to the whole of the United Kingdom, including Northern Ireland, this is not correct. Britain can refer to either all island
Panamax
Panamax and New Panamax are terms for the size limits for ships travelling through the Panama Canal. The limits and requirements are published by the Panama Canal Authority in a publication titled "Vessel Requirements"; these requirements describe topics like exceptional dry seasonal limits, propulsion and detailed ship design. The allowable size is limited by the width and length of the available lock chambers, by the depth of water in the canal, by the height of the Bridge of the Americas since that bridge's construction; these dimensions give clear parameters for ships destined to traverse the Panama Canal and have influenced the design of cargo ships, naval vessels, passenger ships. Panamax specifications have been in effect since the opening of the canal in 1914. In 2009 the ACP published the New Panamax specification which came into effect when the canal's third set of locks, larger than the original two, opened on 26 June 2016. Ships that do not fall within the Panamax-sizes are called super-Panamax.
The increasing prevalence of vessels of the maximum size is a problem for the canal, as a Panamax ship is a tight fit that requires precise control of the vessel in the locks resulting in longer lock time, requiring that these ships transit in daylight. Because the largest ships traveling in opposite directions cannot pass safely within the Culebra Cut, the canal operates an alternating one-way system for these ships. Panamax is determined principally by the dimensions of the canal's original lock chambers, each of, 110 ft wide, 1,050 ft long, 41.2 ft deep. The usable length of each lock chamber is 1,000 ft; the available water depth in the lock chambers varies, but the shallowest depth is at the south sill of the Pedro Miguel Locks and is 41.2 ft at a Miraflores Lake level of 54 ft 6 in. The clearance under the Bridge of the Americas at Balboa is the limiting factor on a vessel's overall height for both Panamax and Neopanamax ships; the maximum dimensions allowed for a ship transiting the canal using the original locks and the new locks are: Overall: 950 ft. Exceptions: Container ship and passenger ship: 965 ft Tug-barge combination, rigidly connected: 900 ft overall Other non-self-propelled vessels-tug combination: 850 ft overall.
Width over outer surface of the shell plating: 106 ft. General exception: 107 ft, when draft is less than 37 ft in tropical fresh water. New Panamax increases allowable width to 49 m; the maximum allowable draft is 39.5 ft in Tropical Fresh Water. The name and definition of TFW is created by ACP using the freshwater Lake Gatún as a reference, since this is the determination of the maximum draft; the salinity and temperature of water affect its density, hence how deep a ship will float in the water. Tropical Fresh Water is fresh water of Lake Gatún, with density 0.9954 g/cm3, at 29.1 °C. The physical limit is set by the lower entrance of the Pedro Miguel locks; when the water level in Lake Gatún is low during an exceptionally dry season the maximum permitted draft may be reduced. Such a restriction is published three weeks in advance, so ship loading plans can take appropriate measures. New Panamax increases allowable draft to 15.2 m, however due to low rainfall, the canal authority limited draft to 43 feet when the new locks opened in June 2016, increasing it to 44 feet, in August "based on the current level of Gatun Lake and the weather forecast for the following weeks."
Vessel height is limited to 190 ft measured from the waterline to the vessel's highest point. Exception: 205 ft when passage at low water at Balboa is possible. All exceptions are allowed only after specific request and an investigation, on a once- or twice-only basis. A Panamax cargo ship would have a DWT of 65,000–80,000 tonnes, but its maximum cargo would be about 52,500 tonnes during a transit due to draft limitations in the canal. New Panamax ships can carry 120,000 DWT. Panamax container ships can carry 5,000 twenty-foot equivalent units; the longest ship to transit the original locks was San Juan Prospector, now Marcona Prospector, an ore-bulk-oil carrier, 973 ft long, with a beam of 106 ft. The widest ships to transit are the four Iowa-class battleships, which have a maximum beam of 108 ft, leaving less than 6 in margin of error between the ships and the walls of the locks; as early as the 1930s, new locks were proposed for the Panama Canal to ease congestion and to allow larger ships to pass.
The project was abandoned in 1942. On October 22, 2006, the Panama Canal Authority held a referendum for Panamanian citizens to vote on the Panama Canal expansion project; the expansion was approved with support from about 78 % of the electorate. Construction began in 2007, after several delays, the new locks opened for commercial traffic on 26 June 2016; the plans to build another set of larger locks led to the creation of the Neopanamax or New Panamax ship classification, based on the new locks' dimensions of 427 m in length, 55 m in beam, 18.3 m in depth. Naval architects and civil engineers began taking into account these dimensions for container
Handysize
Handysize is a naval architecture term for smaller bulk carriers or oil tanker with deadweight of up to 50,000 tonnes, although there is no official definition in terms of exact tonnages. Handysize is sometimes used to refer to the span of up to 60,000 tons, with the vessels above 35,000 tonnes referred to as Handymax or Supramax, their small size allows Handysize vessels to enter smaller ports to pick up cargoes, because in most cases they are'geared' - i.e. fitted with cranes - they can load and discharge cargoes at ports which lack cranes or other cargo handling systems. Compared to larger bulk carriers, handysizes carry a wider variety of cargo types; these include steel products, metal ores, cement, logs and other types of so-called'break bulk cargo'. They are numerically the most common size of bulk carrier, with nearly 2000 units in service totalling about 43 million tons. Handysize bulkers are built by shipyards in Japan, China, the Philippines and India, though a few other countries have the capacity to build such vessels.
The most common industry-standard specification handysize bulker is now about 32,000 metric tons of deadweight on a summer draft of about 10 metres, features 5 cargo holds with hydraulically operated hatch covers, with four 30 metric ton cranes for cargo handling. Some handysizes are fitted with stanchions to enable logs to be loaded in stacks on deck; such vessels are referred to as'handy loggers'. - Despite multiple recent orders for new ships, the handysize sector still has the highest average age profile of the major bulk carrier sectors. Today, most of handysize vessels operate within regional trade routes; these ships are capable of traveling to small ports with length and draught restrictions, as well as lacking the infrastructure for cargo loading and unloading. They are used to carry small bulk cargoes in parcel size where individual cargo holds may have a different commodity, their dry bulk cargo includes iron ore, cement, finished steel products, wooden logs and grains to name a few.
Ship sizes
Common logarithm
In mathematics, the common logarithm is the logarithm with base 10. It is known as the decadic logarithm and as the decimal logarithm, named after its base, or Briggsian logarithm, after Henry Briggs, an English mathematician who pioneered its use, as well as standard logarithm, it was known as logarithmus decimalis or logarithmus decadis. It is indicated by log10, or sometimes Log with a capital L. On calculators, it is "log", but mathematicians mean natural logarithm rather than common logarithm when they write "log". To mitigate this ambiguity, the ISO 80000 specification recommends that log10 should be written lg and loge should be ln. Before the early 1970s, handheld electronic calculators were not available and mechanical calculators capable of multiplication were bulky and not available. Instead, tables of base-10 logarithms were used in science and navigation when calculations required greater accuracy than could be achieved with a slide rule. Use of logarithms avoided error-prone paper-and-pencil multiplications and divisions.
Because logarithms were so useful, tables of base-10 logarithms were given in appendices of many textbooks. Mathematical and navigation handbooks included tables of the logarithms of trigonometric functions as well. See log table for the history of such tables. An important property of base-10 logarithms, which makes them so useful in calculations, is that the logarithm of numbers greater than 1 that differ by a factor of a power of 10 all have the same fractional part; the fractional part is known as the mantissa. Thus log tables need only show the fractional part. Tables of common logarithms listed the mantissa, to four or five decimal places or more, of each number in a range, e.g. 1000 to 9999. Such a range would cover all possible values of the mantissa; the integer part, called the characteristic, can be computed by counting how many places the decimal point must be moved so that it is just to the right of the first significant digit. For example, the logarithm of 120 is given by the following calculation: log 10 = log 10 = 2 + log 10 ≈ 2 + 0.07918.
The last number —the fractional part or the mantissa of the common logarithm of 120—can be found in the table shown. The location of the decimal point in 120 tells us that the integer part of the common logarithm of 120, the characteristic, is 2. Numbers greater than 0 and less than 1 have negative logarithms. For example, log 10 = log 10 = − 2 + log 10 ≈ − 2 + 0.07918 = − 1.92082. To avoid the need for separate tables to convert positive and negative logarithms back to their original numbers, a bar notation is used: log 10 ≈ − 2 + 0.07918 = 2 ¯.07918. The bar over the characteristic indicates; when reading a number in bar notation out loud, the symbol n ¯ is read as "bar n", so that 2 ¯.07918 is read as "bar 2 point 07918…". The following example uses the bar notation to calculate 0.012 × 0.85 = 0.0102: As found above, log 10 ≈ 2 ¯.07918 Since log 10 = log 10 = − 1 + log 10 ≈ − 1 + 0.92942 = 1 ¯.92942 log 10 = log 10 + log 10 ( 0
Hull (watercraft)
A hull is the watertight body of a ship or boat. The hull may open at the top, or it may be or covered with a deck. Atop the deck may be a deckhouse and other superstructures, such as a funnel, derrick, or mast; the line where the hull meets the water surface is called the waterline. 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 and special considerations for the ship's role, such as the rounded bow of an icebreaker or the flat bottom of a landing craft. In a typical modern steel ship, the hull will have watertight decks, major transverse members called bulkheads. There may be intermediate members such as girders and webs, minor members called ordinary transverse frames, frames, or longitudinals, depending on the structural arrangement.
The uppermost continuous deck may be called the "upper deck", "weather deck", "spar deck", "main deck", or "deck". The particular name given depends on the context—the type of ship or boat, the arrangement, or where it sails. In a typical wooden sailboat, the hull is constructed of wooden planking, supported by transverse frames and bulkheads, which are further tied together by longitudinal stringers or ceiling, but not always there is a centerline longitudinal member called a keel. In fiberglass or composite hulls, the structure may resemble wooden or steel vessels to some extent, or be of a monocoque arrangement. In many cases, composite hulls are built by sandwiching thin fiber-reinforced skins over a lightweight but reasonably rigid core of foam, balsa wood, impregnated paper honeycomb or other material; the earliest proper hulls were built by the Ancient Egyptians, who by 3000 BC knew how to assemble wooden planks into ahull. See also: Hull Hulls come in many varieties and can have composite shape, but are grouped as follows: Chined and Hard-chined.
Examples are the flat-bottom, v-bottom, multi-bottom hull. These types have at least one pronounced knuckle throughout most of their length. Moulded, round soft-chined; these hull shapes all have smooth curves. Examples are the round bilge, semi-round bilge, s-bottom hull. Displacement hull: here the hull is supported or predominantly by buoyancy. Vessels that have this type of hull travel through the water at a limited rate, defined by the waterline length, they are though not always, heavier than planing types. Planing hull: here, the planing hull form is configured to develop positive dynamic pressure so that its draft decreases with increasing speed; the dynamic lift reduces the wetted surface and therefore the drag. They are sometimes flat-bottomed, sometimes V-bottomed and more round-bilged; the most common form is to have at least one chine, which makes for more efficient planing and can throw spray down. Planing hulls are more efficient at higher speeds, although they still require more energy to achieve these speeds.
An effective planing hull must be as light as possible with flat surfaces that are consistent with good sea keeping. Sail boats that plane must sail efficiently in displacement mode in light winds. Semi-displacement, or semi-planing: here the hull form is capable of developing a moderate amount of dynamic lift. At present, the most used form is the round bilge hull. In the inverted bell shape of the hull, with a smaller payload the waterline cross-section is less, hence the resistance is less and the speed is higher. With a higher payload the outward bend provides smoother performance in waves; as such, the inverted bell shape is a popular form used with planing hulls. A chined hull consists of straight, tall, long, or short plates, timbers or sheets of ply, which are set at an angle to each other when viewed in transverse section; the traditional chined hull is a simple hull shape because it works with only straight planks bent into a curve. These boards are bent lengthwise. Plywood chined boats made of 8' x 4' sheets have most bend along the long axis of the sheet.
Only thin ply 3–6 mm can be shaped into a compound bend. Most home-made constructed boats are chined hull boats. Mass-produced chine powerboats are made of sprayed chop strand fibreglass over a wooden mold; the Cajun "pirogue" is an example of a craft with hard chines. Benefits of this type of hull is the low production cost and the flat bottom, making the boat faster at planing. Sail boats with chined hull make use of a dagger keel. Chined hulls may have one of three shapes: Flat-bottom chined hulls Multi-chined hulls V-bottom chined hulls. Sometimes called hard chine; each of these chine hulls use. The flat bottom hull has high initial stability but high drag. To counter the high drag hull forms are narrow and sometimes tapered at bow and stern; this leads to poor stability. This is countered by using heavy interior ballast on sailing versions, they are best suited to sheltered inshore waters. Early racing power boats were flat aft; this produced maximum lift and a smooth,fast ride in flat water but this hull form is unsettled in waves.
The multi chine h
