The tonne referred to as the metric ton in the United States and Canada, is a non-SI metric unit of mass equal to 1,000 kilograms or one megagram. It is equivalent to 2,204.6 pounds, 1.102 short tons or 0.984 long tons. Although not part of the SI, the tonne is accepted for use with SI units and prefixes by the International Committee for Weights and Measures; the tonne is derived from the weight of 1 cubic metre of pure water. The SI symbol for the tonne is't', adopted at the same time as the unit in 1879, its use is official for the metric ton in the United States, having been adopted by the United States National Institute of Standards and Technology. It is a symbol, not an abbreviation, should not be followed by a period. Use of upper and lower case is significant, use of other letter combinations is not permitted and would lead to ambiguity. For example,'T','MT','Mt','mt' are the SI symbols for the tesla, megatesla and millitonne respectively. If describing TNT equivalent units of energy, this is equivalent to 4.184 petajoules.
In French and most varieties of English, tonne is the correct spelling. It is pronounced the same as ton, but when it is important to clarify that the metric term is meant, rather than short ton, the final "e" can be pronounced, i.e. "tonny". In Australia, it is pronounced. Before metrication in the UK the unit used for most purposes was the Imperial ton of 2,240 pounds avoirdupois or 20 hundredweight, equivalent to 1,016 kg, differing by just 1.6% from the tonne. The UK Weights and Measures Act 1985 explicitly excluded from use for trade certain imperial units, including the ton, unless the item being sold or the weighing equipment being used was weighed or certified prior to 1 December 1980, then only if the buyer was made aware that the weight of the item was measured in imperial units. In the United States metric ton is the name for this unit used and recommended by NIST. Both spellings are acceptable in Canadian usage. Ton and tonne are both derived from a Germanic word in general use in the North Sea area since the Middle Ages to designate a large cask, or tun.
A full tun, standing about a metre high, could weigh a tonne. An English tun of wine weighs a tonne, 954 kg if full of water, a little less for wine; the spelling tonne pre-dates the introduction of the SI in 1960. In the United States, the unit was referred to using the French words millier or tonneau, but these terms are now obsolete; the Imperial and US customary units comparable to the tonne are both spelled ton in English, though they differ in mass. One tonne is equivalent to: Metric/SI: 1 megagram. Equal to 1000000 grams or 1000 kilograms. Megagram, Mg, is the official SI unit. Mg is distinct from milligram. Pounds: Exactly 1000/0.453 592 37 lb, or 2204.622622 lb. US/Short tons: Exactly 1/0.907 184 74 short tons, or 1.102311311 ST. One short ton is 0.90718474 t. Imperial/Long tons: Exactly 1/1.016 046 9088 long tons, or 0.9842065276 LT. One long ton is 1.0160469088 t. For multiples of the tonne, it is more usual to speak of millions of tonnes. Kilotonne and gigatonne are more used for the energy of nuclear explosions and other events in equivalent mass of TNT loosely as approximate figures.
When used in this context, there is little need to distinguish between metric and other tons, the unit is spelt either as ton or tonne with the relevant prefix attached. *The equivalent units columns use the short scale large-number naming system used in most English-language countries, e.g. 1 billion = 1,000 million = 1,000,000,000.†Values in the equivalent short and long tons columns are rounded to five significant figures, see Conversions for exact values.ǂThough non-standard, the symbol "kt" is used for knot, a unit of speed for aircraft and sea-going vessels, should not be confused with kilotonne. A metric ton unit can mean 10 kilograms within metal trading within the US, it traditionally referred to a metric ton of ore containing 1% of metal. The following excerpt from a mining geology textbook describes its usage in the particular case of tungsten: "Tungsten concentrates are traded in metric tonne units (originally designating one tonne of ore containing 1% of WO3, today used to measure WO3 quantities in 10 kg units.
One metric tonne unit of tungsten contains 7.93 kilograms of tungsten." Note that tungsten is known as wolfram and has the atomic symbol W. In the case of uranium, the acronym MTU is sometimes considered to be metric ton of uranium, meaning 1,000 kg. A gigatonne of carbon dioxide equivalent is a unit used by the UN climate change panel, IPCC, to measure the effect of a technolo
The Shirane-class destroyers were a pair of Japanese destroyers built during the late 1970s. They are built around a large central hangar which houses up to three helicopters and they are the natural successor of the Haruna-class destroyers; the Shirane class incorporates an improved design based on the Haruna-class destroyers. The ships propulsion include two steam boilers with two shafts that produce 70.000 hp and gives a maximum speed of 32 knots. Its armament includes two Mk.42 127mm guns, two 20-mm Phalanx close-in weapon systems, one Surface-to-air RIM-7 Sea Sparrow launcher and anti-submarine rockets. The ships has been replaced by the new Izumo-class helicopter destroyers. On December 15, 2007, a fire broke out on board Shirane near the rudder house as it was anchored at Yokosuka, it took seven hours to extinguish the fire. On 27 October 2009, JS Kurama collided with a South Korean container ship under the Kanmonkyo Bridge in the Kanmon Straits off the coast of Japan. While neither ship sunk, the bow of Kurama was badly burned for hours.
Three Kurama crew members were reported injured. GlobalSecurity.org.
The Yūgumo-class destroyers were a group of 19 destroyers built for the Imperial Japanese Navy during World War II. The IJN called them Destroyer Type-A from their plan name. No ships of the class survived the war; the Yūgumo class was a repeat of the preceding Kagerō class with minor improvements that increased their anti-aircraft capabilities. The first 11 ships of the class were ordered as part of the 1939 4th Naval Armaments Supplement Programme. Another 16 ships were ordered as part of the 1941 Rapid Naval Armaments Supplement Programme, but of these eight were canceled before being laid down. Another eight ships were planned under the 1942 Modified 5th Naval Armaments Supplement Programme, but these were canceled; the Yūgumo class was 45 tons heavier and a few feet longer than the Kagerō class, distinguishable in silhouette by the shape of the bridge. The Yūgumo class had a forward slope on the bridge, intended to reduce wind resistance and improve stability. Another difference was that the Yūgumo-class vessels were built by three different shipyards, there were minor differences between individual ships, depending on the builder and when the ship was built.
The general specifications for the Yūgumo class was a 119.17-meter overall length, with a beam of 10.8 meters and a draft of 3.76 meters. They displaced 2,110 metric tons at 2,560 metric tons at deep load, their crew enlisted men. The ships had two Kampon geared steam turbines, each driving one propeller shaft, using steam provided by three Kampon water-tube boilers; the turbines were rated at a total of 52,000 shaft horsepower for a designed speed of 35 knots. The main battery of the Yūgumo class consisted of six Type 3 127-millimeter guns in three twin-gun turrets, one superfiring pair aft and one turret forward of the superstructure; the guns were in a new type of mount, able to elevate up to 75° to increase their performance against aircraft. The ships were armed with eight 610-millimeter torpedo tubes in a two quadruple traversing mounts, their anti-submarine weapons comprised two depth charge throwers for which 36 depth charges were carried. As built, the Yūgumo class had four Type 96 25-millimeter anti-aircraft guns in two twin-mounts forward of the aft smokestack.
As with other destroyer classes, as the Pacific War progressed, anti-aircraft armaments were increased. Two triple-mount and one twin-mount Type 96 were added forward of the bridge and a Type 22 radar. Units surviving into 1944 had a second triple-mount added on a platform behind the forward smokestack; the six units surviving into 1944 received up to twelve additional single-mount Type 96s and a Type 13 radar. Kiyoshimo received a number of Type 93 13mm machine guns; the Yūgumo class were considered elite units and always assigned to escort primary fleet units. They were all lost during the Pacific War. Campbell, John. Naval Weapons of World War II. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-459-4. Campbell, John. Naval Weapons of World War II. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-459-4. Chesneau, Roger, ed.. Conway's All the World's Fighting Ships 1922–1946. Greenwich, UK: Conway Maritime Press. ISBN 0-85177-146-7. Jentschura, Hansgeorg. Warships of the Imperial Japanese Navy, 1869–1945.
Annapolis, Maryland: United States Naval Institute. ISBN 0-87021-893-X. Whitley, M. J.. Destroyers of World War 2. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-326-1. "Rekishi Gunzō". History of Pacific War Vol.51 The truth of Imperial Japanese Vessels Histories 2, August 2005, ISBN 4-05-604083-4 Collection of writings by Sizuo Fukui Vol.5, Stories of Japanese Destroyers, Kōjinsha 1993, ISBN 4-7698-0611-6 Model Art Extra No.340, Drawings of Imperial Japanese Naval Vessels Part-1, Model Art Co. Ltd. October 1989, Book code 08734-10 The Maru Special, Japanese Naval Vessels No.41 Japanese Destroyers I, Ushio Shobō, July 1980, Book code 68343-42 http://www.combinedfleet.com/yugumo_n.htm
Japan is an island country in East Asia. Located in the Pacific Ocean, it lies off the eastern coast of the Asian continent and stretches from the Sea of Okhotsk in the north to the East China Sea and the Philippine Sea in the south; the kanji that make up Japan's name mean "sun origin", it is called the "Land of the Rising Sun". Japan is a stratovolcanic archipelago consisting of about 6,852 islands; the four largest are Honshu, Hokkaido and Shikoku, which make up about ninety-seven percent of Japan's land area and are referred to as home islands. The country is divided into 47 prefectures in eight regions, with Hokkaido being the northernmost prefecture and Okinawa being the southernmost one; the population of 127 million is the world's tenth largest. 90.7 % of people live in cities. About 13.8 million people live in the capital of Japan. The Greater Tokyo Area is the most populous metropolitan area in the world with over 38 million people. Archaeological research indicates; the first written mention of Japan is in Chinese history texts from the 1st century AD.
Influence from other regions China, followed by periods of isolation from Western Europe, has characterized Japan's history. From the 12th century until 1868, Japan was ruled by successive feudal military shōguns who ruled in the name of the Emperor. Japan entered into a long period of isolation in the early 17th century, ended in 1853 when a United States fleet pressured Japan to open to the West. After nearly two decades of internal conflict and insurrection, the Imperial Court regained its political power in 1868 through the help of several clans from Chōshū and Satsuma – and the Empire of Japan was established. In the late 19th and early 20th centuries, victories in the First Sino-Japanese War, the Russo-Japanese War and World War I allowed Japan to expand its empire during a period of increasing militarism; the Second Sino-Japanese War of 1937 expanded into part of World War II in 1941, which came to an end in 1945 following the Japanese surrender. Since adopting its revised constitution on May 3, 1947, during the occupation led by SCAP, the sovereign state of Japan has maintained a unitary parliamentary constitutional monarchy with an Emperor and an elected legislature called the National Diet.
Japan is a member of the ASEAN Plus mechanism, UN, the OECD, the G7, the G8, the G20, is considered a great power. Its economy is the world's third-largest by nominal GDP and the fourth-largest by purchasing power parity, it is the world's fourth-largest exporter and fourth-largest importer. Japan benefits from a skilled and educated workforce. Although it has renounced its right to declare war, Japan maintains a modern military with the world's eighth-largest military budget, used for self-defense and peacekeeping roles. Japan is a developed country with a high standard of living and Human Development Index, its population enjoys the highest life expectancy and third lowest infant mortality rate in the world, but is experiencing issues due to an aging population and low birthrate. Japan is renowned for its historical and extensive cinema, influential music industry, video gaming, rich cuisine and its major contributions to science and modern technology; the Japanese word for Japan is 日本, pronounced Nihon or Nippon and means "the origin of the sun".
The character nichi means "sun" or "day". The compound therefore means "origin of the sun" and is the source of the popular Western epithet "Land of the Rising Sun"; the earliest record of the name Nihon appears in the Chinese historical records of the Tang dynasty, the Old Book of Tang. At the end of the seventh century, a delegation from Japan requested that Nihon be used as the name of their country; this name may have its origin in a letter sent in 607 and recorded in the official history of the Sui dynasty. Prince Shōtoku, the Regent of Japan, sent a mission to China with a letter in which he called himself "the Emperor of the Land where the Sun rises"; the message said: "Here, I, the emperor of the country where the sun rises, send a letter to the emperor of the country where the sun sets. How are you". Prior to the adoption of Nihon, other terms such as Yamato and Wakoku were used; the term Wa is a homophone of Wo 倭, used by the Chinese as a designation for the Japanese as early as the third century Three Kingdoms period.
Another form of Wa, Wei in Chinese) was used for an early state in Japan called Nakoku during the Han dynasty. However, the Japanese disliked some connotation of Wa 倭, it was therefore replaced with the substitute character Wa, meaning "togetherness, harmony"; the English word Japan derives from the historical Chinese pronunciation of 日本. The Old Mandarin or early Wu Chinese pronunciation of Japan was recorded by Marco Polo as Cipangu. In modern Shanghainese, a Wu dialect, the pronunciation of characters 日本; the old Malay word for Japan, Japun or Japang, was borrowed from a southern coastal Chinese dialect Fukienese or Ningpo – and this Malay word was encountered by Portuguese traders in Southeast Asia in the 16th century. These Early Portuguese traders brought the word
The Tachikaze-class destroyer is a second generation guided missile destroyer class in service with the Japan Maritime Self-Defense Force. The ships of this class have had successive improvements after their completion to their C4I systems; these air-defense warships are the natural successor to the first generation air-defense ship, the Amatsukaze-class destroyer, they were in turn, followed by newer air-defense ships, the Hatakaze class. The Tachikaze class was equipped with the Tartar-D system as the key weapon system, the fleet-area air defense weapon system with the Standard-1 MR missile. At the same time, this was the American first native integrated weapon system with the Naval Tactical Data System, so this class was the first of the Maritime Self Defense Force's ships that utilised computers widely; as the NTDS, OYQ-1 Weapon Entry System was on board on Tachikaze. The OYQ-1 WES was based on the technology of the NYYA-1, on board on the lead ship of the Takatsuki class, this system was the first Japanese shipboard C4I system with the architecture of NTDS.
On the second ship, the improved OYQ-2 Target Designation System was on board. And the third ship, introduced the new-generation combat direction system, OYQ-4; the Tachikaze-class destroyers' weapon systems include one Mk 13 missile launcher for the Standard-1 MR surface-to-air missile, one Type 74 octuple launcher for the ASROC anti-submarine rockets, eight Boeing Harpoon anti-ship missile, two 20-mm Phalanx CIWS gun mounts, two Type 68 triple 324 mm torpedo tubes, two 5-inch/54 caliber Mark 42 rapid-fire guns. In 1998, Tachikaze was converted to be the flagship of the Fleet Escort Force; the aft 5-inch gun was replaced with a fleet command area. Tachikaze was decommissioned in 2007. Sawakaze succeeded her in the flagship role; the ships of the Tachikaze class were decommissioned beginning in 2007. All three vessels of the Tachikaze class were named after destroyers of the Imperial Japanese Navy, with Tachikaze and Asakaze being lost to enemy action during the war. Heihachiro Fujiki. "A history of JMSDF's missile destroyers".
Ships of the World. Kaijinn-sha: 98–103. GlobalSecurity.org.
Radar is a detection system that uses radio waves to determine the range, angle, or velocity of objects. It can be used to detect aircraft, spacecraft, guided missiles, motor vehicles, weather formations, terrain. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwaves domain, a transmitting antenna, a receiving antenna and a receiver and processor to determine properties of the object. Radio waves from the transmitter reflect off the object and return to the receiver, giving information about the object's location and speed. Radar was developed secretly for military use by several nations in the period before and during World War II. A key development was the cavity magnetron in the UK, which allowed the creation of small systems with sub-meter resolution; 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 a common noun, losing all capitalization.
The modern uses of radar are diverse, including air and terrestrial traffic control, radar astronomy, air-defense systems, antimissile systems, marine radars to locate landmarks and other ships, aircraft anticollision systems, ocean surveillance systems, outer space surveillance and rendezvous systems, meteorological precipitation monitoring and flight control systems, guided missile target locating systems, ground-penetrating radar for geological observations, range-controlled radar for public health surveillance. High tech radar systems are associated with digital signal processing, machine learning and are capable of extracting useful information from high noise levels. Radar is a key technology that the self-driving systems are designed to use, along with sonar and other sensors. Other systems similar to radar make use of other parts of the electromagnetic spectrum. One example is "lidar". With the emergence of driverless vehicles, Radar is expected to assist the automated platform to monitor its environment, thus preventing unwanted incidents.
As early as 1886, German physicist Heinrich Hertz showed that radio waves could be reflected from solid objects. In 1895, Alexander Popov, a physics instructor at the Imperial Russian Navy school in Kronstadt, developed an apparatus using a coherer tube for detecting distant lightning strikes; the next year, he added a spark-gap transmitter. In 1897, while testing this equipment for communicating between two ships in the Baltic Sea, he took note of an interference beat caused by the passage of a third vessel. In his report, Popov wrote that this phenomenon might be used for detecting objects, but he did nothing more with this observation; the German inventor Christian Hülsmeyer was the first to use radio waves to detect "the presence of distant metallic objects". In 1904, he demonstrated the feasibility of detecting a ship in dense fog, but not its distance from the transmitter, he obtained a patent for his detection device in April 1904 and a patent for a related amendment for estimating the distance to the ship.
He got a British patent on September 23, 1904 for a full radar system, that he called a telemobiloscope. It operated on a 50 cm wavelength and the pulsed radar signal was created via a spark-gap, his system used the classic antenna setup of horn antenna with parabolic reflector and was presented to German military officials in practical tests in Cologne and Rotterdam harbour but was rejected. In 1915, Robert Watson-Watt used radio technology to provide advance warning to airmen and during the 1920s went on to lead the U. K. research establishment to make many advances using radio techniques, including the probing of the ionosphere and the detection of lightning at long distances. Through his lightning experiments, Watson-Watt became an expert on the use of radio direction finding before turning his inquiry to shortwave transmission. Requiring a suitable receiver for such studies, he told the "new boy" Arnold Frederic Wilkins to conduct an extensive review of available shortwave units. Wilkins would select a General Post Office model after noting its manual's description of a "fading" effect when aircraft flew overhead.
Across the Atlantic in 1922, after placing a transmitter and receiver on opposite sides of the Potomac River, U. S. Navy researchers A. Hoyt Taylor and Leo C. Young discovered that ships passing through the beam path caused the received signal to fade in and out. Taylor submitted a report, suggesting that this phenomenon might be used to detect the presence of ships in low visibility, but the Navy did not continue the work. Eight years Lawrence A. Hyland at the Naval Research Laboratory observed similar fading effects from passing aircraft. Before the Second World War, researchers in the United Kingdom, Germany, Japan, the Netherlands, the Soviet Union, the United States, independently and in great secrecy, developed technologies that led to the modern version of radar. Australia, New Zealand, South Africa followed prewar Great Britain's radar development, Hungary generated its radar technology during the war. In France in 1934, following systematic studies on the split-anode magnetron, the research branch of the Compagnie Générale de Télégraphie Sans Fil headed by Maurice Ponte with Henri Gutton, Sylvain Berline and M. Hugon, began developing an obstacle-locatin
Japan Maritime Self-Defense Force
The Japan Maritime Self-Defense Force, JMSDF referred to as the Japanese Navy, is the maritime warfare branch of the Japan Self-Defense Forces, tasked with the naval defense of Japan. It is the de facto navy of Japan and was formed following the dissolution of the Imperial Japanese Navy after World War II; the JMSDF has a fleet of 154 ships and 346 aircraft and consists of 45,800 personnel. Its main tasks are to patrol territorial waters, it participates in UN-led peacekeeping operations and Maritime Interdiction Operations. Japan has a long history of naval interaction with the Asian continent, involving the transportation of troops, starting at least with the beginning of the Kofun period in the 3rd century. Following the attempts at Mongol invasions of Japan by Kublai Khan in 1274 and 1281, Japanese wakō became active in plundering the coast of the Chinese Empire. Japan undertook major naval building efforts in the 16th century, during the Warring States period, when feudal rulers vying for supremacy built vast coastal navies of several hundred ships.
Around that time, Japan may have developed one of the world's first ironclad warships, when Oda Nobunaga had six iron-covered Oatakebune made in 1576. In 1588, Toyotomi Hideyoshi issued a ban on Wakō piracy. Japan built her first large ocean-going warships in the beginning of the 17th century, following contact with European countries during the Nanban trade period. In 1613, the daimyō of Sendai, in agreement with the Tokugawa shogunate, built Date Maru; this 500 ton galleon-type ship transported the Japanese embassy of Hasekura Tsunenaga to the Americas and Europe. From 1604 onwards, about 350 Red seal ships armed and incorporating European technology, were commissioned by the shogunate for Southeast Asian trade. From 1868, the restored Meiji Emperor continued with reforms to industrialize and militarize Japan to prevent the United States and European powers from overwhelming it. On 17 January 1868, the Ministry of Military Affairs was established, with Iwakura Tomomi, Shimazu Tadayoshi and Prince Komatsu-no-miya Akihito as the First Secretaries.
On 26 March 1868, the first Naval Review was held in Japan, with 6 ships from the private domainal navies of Saga, Chōshū, Kurume and Hiroshima participating. The total tonnage of these ships was 2,252 tons, far smaller than the tonnage of the single foreign vessel that participated. In July 1869, the Imperial Japanese Navy was formally established, two months after the last military engagement of the Boshin War – the private navies of the Japanese nobles were abolished and their 11 ships were added to the 7 surviving vessels of the defunct Tokugawa bakufu navy, including Kankō Maru, Japan's first steam warship; this formed the core of the new Imperial Japanese Navy. An 1872 edict separated the Japanese Navy from the Japanese Army. Politicians like Enomoto Takeaki set out to use the Navy to expand to the islands south of Japan in similar fashion to the Army's northern and western expansion; the Navy sought to upgrade its fleet to a blue water navy and used cruises to expand the Japanese consciousness on the southern islands.
Enomoto's policies helped the Navy expand and incorporate many different islands into the Japanese Empire, including Iwo Jima in 1889. The navy continued to expand and incorporate political influence throughout the early twentieth century. Following Japan's defeat in World War II, the Imperial Japanese Navy was dissolved by the Potsdam Declaration acceptance. Ships were disarmed, some of them, such as the battleship Nagato, were taken by the Allied Powers as reparation; the remaining ships were used for repatriation of the Japanese soldiers from abroad and for minesweeping in the area around Japan under the control of the Second Bureau of the Demobilization Ministry. The minesweeping fleet was transferred to the newly formed Maritime Safety Agency, which helped maintain the resources and expertise of the navy. Japan's 1947 Constitution was drawn up after the conclusion of the war, Article 9 specifying that "The Japanese people forever renounce war as a sovereign right of the nation and the threat or use of force as a means of settling international disputes."
The prevalent view in Japan is that this article allows for military forces to be kept for the purposes of self-defense. Due to Cold War pressures, the United States was happy for Japan to provide part of its own defense, rather than have it rely on American forces. In 1952, the Coastal Safety Force was formed within the Maritime Safety Agency, incorporating the minesweeping fleet and other military vessels destroyers, given by the United States. In 1954, the Coastal Safety Force was separated, the JMSDF was formally created as the naval branch of the Japan Self-Defense Forces, following the passage of the 1954 Self-Defense Forces Law; the first ships in the JMSDF were former U. S. Navy destroyers, transferred to Japanese control in 1954. In 1956, the JMSDF received its first domestically produced destroyer since Harukaze. Due to the Cold War threat posed by the Soviet Navy's sizable and powerful submarine fleet, the JMSDF was tasked with an anti-submarine role. Following the end of the Cold War, the role of the JMSDF has vastly changed.
In 1991, after much international pressure, the JMSDF dispatched four minesweepers, a fleet oiler and a minesweeping tender to the Persian Gulf in the aftermath of the Gulf War, under the name of Operation Gulf Dawn, to clear mines