Deadweight tonnage or tons deadweight is a measure of how much weight a ship can carry, not its weight, empty or in any degree of load. DWT is the sum of the weights of cargo, fresh water, ballast water, provisions and crew. DWT is used to specify a ship's maximum permissible deadweight, although it may denote the actual DWT of a ship not loaded to capacity. Deadweight tonnage is a measure of a vessel's weight carrying capacity, does not include the weight of the ship itself, it should not be confused with displacement, which includes the ship's own weight, nor other volume or capacity measures such as gross tonnage or net tonnage. Deadweight tonnage was expressed in long tons but is now given internationally in tonnes. In modern international shipping conventions such as the International Convention for the Safety of Life at Sea and the International Convention for the Prevention of Pollution From Ships, deadweight is explicitly defined as the difference in tonnes between the displacement of a ship in water of a specific gravity of 1.025 at the draft corresponding to the assigned summer freeboard and the light displacement of the ship.
Barentu is a town in north-western Eritrea, lying south of Agordat, is the capital of Gash-Barka Region. The town is integrated with different types of tribes: Kunama, Nara and Tigrigna being the dominant, it was inhabited by the Nilotic Kunama people and Nara people in the past. The Nara people leader Shekaray Agaba was the first to build the town umba arenku which it means the white water, it is located in the Gash-Barka Zone of Eritrea. Barentu is the largest town in the Gash-Barka Zone in lying west of Asmara, it is home of the Nara and Kunama Ethnic groups. The town has been a center of mining and agricultural activities for the area. During the Eritrean War of Independence the town was besieged; as part of the Eritrean-Ethiopian War of 1998-2000, the flourishing town suffered major damage but has since undergone reconstruction. Thus it now attracts settlers from all parts of the country from the Gash area and the Eritrean highlands. Owing to this factor the town has expanded in the last decade.
This rapid expansion is partly attributed to the Eritrean returnees from Sudan who established their home in the town after years of migration spent in Sudan. Barentu is the administrative center of Barentu Subregion; the town consists of 3 administrative quarters or zobas namely zoba Fthi and Biara. Nearby towns and villages include Tauda, Dedda, Augana and Daghilo, kofa arenku, Arada Tarkina and Lemesa, its climate is warm during summer and cold during winter. Its climate is favorable for different types of vegetables, it is one of the fastest growing cities in the country. It acts as a hub for the surrounding agricultural areas, as a center for trade and exchange of commodities owing to its location in the center of the Gash Barka region; the town is not only growing fast but it is developing with the scale, it have been able to provide basic services, such transport, health facilities and all that coupled with a fine weather. The town gets active on the weekly market days which host farmers and livestock herders who all come to the town on Thursday and Saturday from surrounding villages to sell their produce and in return purchase commodities and goods to take back home.
Products which come from the villages include crops such as sorghum and sesame. Live stocks such as cows, camels and goats fill the market with active sense of exchange when it is near the holidays. Barentu is rich in cultural and social heritages, which will one day make it a tourist site; this is specially true considering the fact that its inhabited by the Kunama and the Nara whose culture and traditions are rich and still remains undiscovered and undisclosed to the world. Education is supplied by a number of elementary and one High school. Schools teach in Kunama, Arabic and English. Transport is supplied with local buses which connect different parts of the town. Media related to Barentu at Wikimedia Commons
An oil tanker known as a petroleum tanker, is a ship designed for the bulk transport of oil or its products. There are two basic types of oil tankers: product tankers. Crude tankers move large quantities of unrefined crude oil from its point of extraction to refineries. For example, moving crude oil from oil wells in Nigeria to the refineries on the coast of the United States. Product tankers much smaller, are designed to move refined products from refineries to points near consuming markets. For example, moving gasoline from refineries in Europe to consumer markets in Nigeria and other West African nations. Oil tankers are classified by their size as well as their occupation; the size classes range from inland or coastal tankers of a few thousand metric tons of deadweight to the mammoth ultra large crude carriers of 550,000 DWT. Tankers move 2,000,000,000 metric tons of oil every year. Second only to pipelines in terms of efficiency, the average cost of oil transport by tanker amounts to only two or three United States cents per 1 US gallon.
Some specialized types of oil tankers have evolved. One of these is a tanker which can fuel a moving vessel. Combination ore-bulk-oil carriers and permanently moored floating storage units are two other variations on the standard oil tanker design. Oil tankers have been involved in a number of high-profile oil spills; as a result, they are subject to operational regulations. The technology of oil transportation has evolved alongside the oil industry. Although human use of oil reaches to prehistory, the first modern commercial exploitation dates back to James Young's manufacture of paraffin in 1850. In the early 1850s, oil began to be exported from Upper Burma a British colony; the oil was moved in earthenware vessels to the river bank where it was poured into boat holds for transportation to Britain. In the 1860s, Pennsylvania oil fields became a major supplier of oil, a center of innovation after Edwin Drake had struck oil near Titusville, Pennsylvania. Break-bulk boats and barges were used to transport Pennsylvania oil in 40-US-gallon wooden barrels.
But transport by barrel had several problems. The first problem was weight: they weighed 64 pounds, representing 20% of the total weight of a full barrel. Other problems with barrels were their expense, their tendency to leak, the fact that they were used only once; the expense was significant: for example, in the early years of the Russian oil industry, barrels accounted for half the cost of petroleum production. In 1863, two sail-driven tankers were built on England's River Tyne; these were followed in 1873 by the first oil-tank steamer, built by Palmers Shipbuilding and Iron Company for Belgian owners. The vessel's use was curtailed by U. S. and Belgian authorities citing safety concerns. By 1871, the Pennsylvania oil fields were making limited use of oil tank barges and cylindrical railroad tank-cars similar to those in use today; the modern oil tanker was developed in the period from 1877 to 1885. In 1876, Ludvig and Robert Nobel, brothers of Alfred Nobel, founded Branobel in Azerbaijan, it was, during the late 19th century, one of the largest oil companies in the world.
Ludvig was a pioneer in the development of early oil tankers. He first experimented with carrying oil in bulk on single-hulled barges. Turning his attention to self-propelled tankships, he faced a number of challenges. A primary concern was to keep the cargo and fumes well away from the engine room to avoid fires. Other challenges included allowing for the cargo to expand and contract due to temperature changes, providing a method to ventilate the tanks; the first successful oil tanker was Zoroaster, which carried its 242 long tons of kerosene cargo in two iron tanks joined by pipes. One tank was forward of the midships engine room and the other was aft; the ship featured a set of 21 vertical watertight compartments for extra buoyancy. The ship had a length overall of 184 feet, a beam of 27 feet, a draft of 9 feet. Unlike Nobel tankers, the Zoroaster design was built small enough to sail from Sweden to the Caspian by way of the Baltic Sea, Lake Ladoga, Lake Onega, the Rybinsk and Mariinsk Canals and the Volga River.
In 1883, oil tanker design took a large step forward. Working for the Nobel company, British engineer Colonel Henry F. Swan designed a set of three Nobel tankers. Instead of one or two large holds, Swan's design used several holds which spanned the width, or beam, of the ship; these holds were further subdivided into starboard sections by a longitudinal bulkhead. Earlier designs suffered from stability problems caused by the free surface effect, where oil sloshing from side to side could cause a ship to capsize, but this approach of dividing the ship's storage space into smaller tanks eliminated free-surface problems. This approach universal today, was first used by Swan in the Nobel tankers Blesk and Lux. Others point to another design of Colonel Swan, as being the first modern oil tanker, it adopted the best practices from previous oil tanker designs to create the prototype for all subsequent vessels of the type. It was the first dedicated steam-driven ocean-going tanker in the world and was the first ship in which oil could be pumped directly into the vessel hull instead of being loaded in barrels or drums.
It was the first tanker with a horizontal bulkhead. The ship w
Italian Eritrea was a colony of the Kingdom of Italy in the territory of present-day Eritrea. Although it was formally created in 1890, the first Italian settlements in the area were established in 1882 around Assab; the colony lasted until 1947. The leading figure of the early history of Italian enterprises in the Red Sea was Giuseppe Sapeto; when a young monk, preparing himself in Cairo for missionary work, he had been dispatched in 1837 into Abyssinia. Afterward, he became an active advocate of European penetration encouraging the French to establish themselves in the area. After 1866, following the political unification of Italy, he sought to develop Italian influence instead; as the Suez Canal neared completion, he began to visualize the establishment of a coaling station and port of call for Italian steamships in the Red Sea. Sapeto won over the Italian minister for foreign affairs, King Victor Emmanuel, to whom he explained his ideas. In the autumn of 1869 he, together with Admiral Acton, was sent by the government to the Red Sea to choose a suitable port and arrange for its sale.
This he did by paying a small deposit to the Danakil chiefs at Assab Bay in return for their promise to sell their territory to him on his return. Meanwhile, the government had been in touch with Raffaele Rubattino, whose company was planning to establish a steamship line through the newly opened Suez Canal and the Red Sea to India, it was agreed that the company would buy the territory in its own name and with its own funds, but should undertake to use it in the national interest. Sapeto returned to the Red Sea on behalf of the company, completed the purchase and bought more land to the south. By March 1870, an Italian shipping company had thus become claimant to territory at the northern end of Assab Bay, a deserted but spacious bay about half-way between Annesley Bay to the north and Obock to the South. However, the area, —, long dominated by the Ottoman Empire and Egypt— was not settled by the Italians until 1880. Two years Italy formally took possession of the nascent colony from its commercial owners.
Most of the western coast of the Red Sea was formally claimed by the Khedivate of Egypt but the region was thrown into chaos by major Egyptian defeats in the Ethio-Egyptian War and by the success of the Mahdi's uprising in the Sudan. In 1884, the British Hewett Treaty promised the Bogos—the highlands of modern Eritrea—and free access to the Massawan coast to Emperor Yohannes IV in exchange for his help evacuating garrisons from the Sudan. Ignoring their treaty with Ethiopia, they encouraged Italy to expand north into Massawa, taken without a shot from its Egyptian garrison. Located on a coral island surrounded by lucrative pearl-fishing grounds, the superior port was fortified and made the capital of the Italian governor. Assab, continued to find service as a coaling station; as they were not a party to the Hewett Treaty, the Italians began restricting access to arms shipments and imposing customs duties on Ethiopian goods immediately. In the disorder that followed the 1889 death of Emperor Yohannes IV, Gen.
Oreste Baratieri occupied the highlands along the Eritrean coast and Italy proclaimed the establishment of a new colony of Eritrea, with capital Asmara in substitution of Massawa. In the Treaty of Wuchale signed the same year, King Menelik of Shewa—a southern Ethiopian kingdom—recognized the Italian occupation of his rivals' lands of Bogos, Akkele Guzay, Serae in exchange for guarantees of financial assistance and continuing access to European arms and ammunition, his subsequent victory over his rival kings and enthronement as Emperor Menelek II made the treaty formally binding upon the entire country. Once established, Menelik took a dim view towards Italian involvement with local leaders in his northern province of Tigray. Negotiations with the French over a railway brought things to a head: the Italian—but not Amharic—version of the Treaty of Wuchale had prohibited Ethiopia with foreign negotiations except through Italy making the realm an Italian protectorate. Secure both domestically and militarily, Menelik denounced the treaty in whole and the ensuing war, culminating in Italy's disastrous defeat at Adwa, ended their hopes of annexing Ethiopia for a time.
During the late twentieth century Assab would become Ethiopia's main port, but it was long overshadowed by nearby Djibouti, whose railway permitted it to supplant traditional caravan-based routes to Assab and Zeila. Massawa remained the primary port for most of northern Ethiopia, but its high customs dues, dependence on caravans, political antagonism limited the volume on its trade with Ethiopia. Seeking to develop their own lands, the Italian government launched the first development projects in the new colony in the late 1880s; the Eritrean Railway was completed to Saati in 1888 and reached Asmara in the highlands in 1911. The Asmara–Massawa Cableway was the longest line in the world during its time. Italian administration of Eritrea brought improvements in the medical and agricultural sectors of E
A highway is any public or private road or other public way on land. It is used for major roads, but includes other public roads and public tracks: It is not an equivalent term to controlled-access highway, or a translation for autobahn, etc. According to Merriam Webster, the use of the term predates 12th century. According to Etymonline, "high" is in the sense of "main". In North American and Australian English, major roads such as controlled-access highways or arterial roads are state highways. Other roads may be designated "county highways" in the Ontario; these classifications refer to the level of government. In British English, "highway" is a legal term. Everyday use implies roads, while the legal use covers any route or path with a public right of access, including footpaths etc; the term has led to several related derived terms, including highway system, highway code, highway patrol and highwayman. The term highway exists in distinction to "waterway". Major highways are named and numbered by the governments that develop and maintain them.
Australia's Highway 1 is the longest national highway in the world at over 14,500 km or 9,000 mi and runs the entire way around the continent. China has the world's largest network of highways followed by the United States of America; some highways, like the European routes, span multiple countries. Some major highway routes include ferry services, such as U. S. Route 10. Traditionally highways were used on horses, they accommodated carriages and motor cars, facilitated by advancements in road construction. In the 1920s and 1930s, many nations began investing in progressively more modern highway systems to spur commerce and bolster national defense. Major modern highways that connect cities in populous developed and developing countries incorporate features intended to enhance the road's capacity and safety to various degrees; such features include a reduction in the number of locations for user access, the use of dual carriageways with two or more lanes on each carriageway, grade-separated junctions with other roads and modes of transport.
These features are present on highways built as motorways. The general legal definition deals with right of use not the form of construction. A highway is defined in English common law by a number of similarly-worded definitions such as "a way over which all members of the public have the right to pass and repass without hindrance" accompanied by "at all times". A highway might be open to all forms of lawful land traffic or limited to specific types of traffic or combinations of types of traffic. A highway can share ground with a private right of way for which full use is not available to the general public as will be the case with farm roads which the owner may use for any purpose but for which the general public only has a right of use on foot or horseback; the status of highway on most older roads has been gained by established public use while newer roads are dedicated as highways from the time they are adopted. In England and Wales, a public highway is known as "The Queen's Highway"; the core definition of a highway is modified in various legislation for a number of purposes but only for the specific matters dealt with in each such piece of legislation.
This is in the case of bridges and other structures whose ownership, mode of use or availability would otherwise exclude them from the general definition of a highway, examples in recent years are toll bridges and tunnels which have the definition of highway imposed upon them to allow application of most traffic laws to those using them but without causing all of the general obligations or rights of use otherwise applicable to a highway. Scots law is similar to English law with regard to highways but with differing terminology and legislation. What is defined in England as a highway will in Scotland be what is defined by s.151 Roads Act 1984 as a road, that is:- "any way over which there is a public right of passage and includes the road’s verge, any bridge over which, or tunnel through which, the road passes. In American law, the word "highway" is sometimes used to denote any public way used for travel, whether a "road and parkway". Highways have a route number designated by t
Ghinda is a town in the Northern Red Sea region of Eritrea. It is situated in the Ghinda Subregion, lies between Asmara and Massawa. Ghinda is a centre for Tigre Muslims, it lies near the springs of Sabarguma. The citrus plantations were planted by Carlo Cavanna, an Italian from Centenaro who directed the construction of the Eritrean Railway, the first railway in Italian Eritrea. Railway stations in Eritrea Ghina, Eritrea
The Boeing 737 is an American short- to medium-range twinjet narrow-body airliner developed and manufactured by Boeing Commercial Airplanes. Developed as a shorter, lower-cost twin-engine airliner derived from the 707 and 727, the 737 has developed into a family of thirteen passenger models with capacities from 85 to 215 passengers; the 737 is Boeing's only narrow-body airliner in production, with the 737 Next Generation and the re-engined and updated 737 MAX variants. The 737 was envisioned in 1964; the initial 737-100 made its first flight in April 1967, entered airline service in February 1968 with Lufthansa. Next, the lengthened 737-200 entered service in April 1968. In the 1980s Boeing launched the longer 737-300, -400, -500 variants featuring CFM56 turbofan engines and wing improvements; the Boeing 737 Next Generation was introduced in the 1990s, with a redesigned, increased span wing, upgraded "glass" cockpit, new interior. The 737 NG comprises the 737-600, -700, -800, -900 variants, with lengths ranging from 31.09 to 42.06 m.
Boeing Business Jet versions of the 737 NG are produced. The 737 was revised again in the 2010s for greater efficiency, with the 737 MAX series featuring CFM LEAP-1B engines and improved winglets; the 737 MAX entered service in 2017 but, after a successful start, was grounded worldwide in March 2019 following two fatal crashes. The 737 series is the highest-selling commercial jetliner in history; the 737 has been continuously manufactured since 1967. Assembly of the 737 is performed at the Boeing Renton Factory in Washington. Many 737s serve markets filled by 707, 727, 757, DC-9, MD-80/MD-90 airliners, the aircraft competes with the Airbus A320 family; as of 2006, there were an average of 1,250 Boeing 737s airborne at any given time, with two either departing or landing somewhere every five seconds. Boeing had been studying short-haul jet aircraft designs, wanted to produce another aircraft to supplement the 727 on short and thin routes. Preliminary design work began on May 11, 1964, Boeing's intense market research yielded plans for a 50- to 60-passenger airliner for routes 50 to 1,000 mi long.
Initial design featured podded engines on the aft fuselage and a T-tail like the 727, five-abreast seating, but engineer Joe Sutter instead placed the engines under the wings to lighten the structure, enabling fuselage widening for six-abreast seating. The 737 design was presented in October 1964 at the Air Transport Association maintenance and engineering conference by chief project engineer Jack Steiner, where its elaborate high-lift devices raised concerns about maintenance costs and dispatch reliability; the launch decision for the $150 million development was made by the board on February 1, 1965. Lufthansa became the launch customer on February 19, 1965, with an order for 21 aircraft, worth $67 million in 1965, after the airline received assurances from Boeing that the 737 project would not be canceled. Consultation with Lufthansa over the previous winter resulted in an increase in capacity to 100 seats. On April 5, 1965, Boeing announced an order by United Airlines for 40 737s. United wanted a larger airplane than the original 737, so Boeing stretched the fuselage 36 in ahead of, 40 in behind the wing.
The longer version was designated 737-200, with the original short-body aircraft becoming the 737-100. Detailed design work continued on both variants at the same time. Boeing was far behind its competitors. To expedite development, Boeing used 60% of the structure and systems of the existing 727, the most notable being the fuselage cross-section; this fuselage permitted six-abreast seating compared to the rival BAC-111 and DC-9's five-abreast layout. Design engineers decided to mount the nacelles directly to the underside of the wings to reduce the landing gear length and kept the engines low to the ground for easy ramp inspection and servicing. Many thickness variations for the engine attachment strut were tested in the wind tunnel and the most desirable shape for high speed was found to be one, thick, filling the narrow channels formed between the wing and the top of the nacelle on the outboard side; the span arrangement of the airfoil sections of the 737 wing was planned to be similar to that of the 707 and 727, but somewhat thicker.
A substantial improvement in drag at high Mach numbers was achieved by altering these sections near the nacelle. The engine chosen was the Pratt & Whitney JT8D-1 low-bypass ratio turbofan engine, delivering 14,500 lbf thrust. With the wing-mounted engines, Boeing decided to mount the horizontal stabilizer on the fuselage rather than the T-tail style of the Boeing 727; the initial assembly of the Boeing 737 was adjacent to Boeing Field because the factory in Renton was filled to capacity with the production of the 707 and 727. After 271 of the Boeing 737 aircraft were built, production was moved to Renton in late 1970. A significant portion of fuselage assembly—previously done by Boeing in Wichita, Kansas—is now performed by Spirit AeroSystems, which purchased some of Boeing's assets in Wichita. Key to increasing production efficiencies, the entire fuselage is shipped since the 737 Next Generation while it was sent in two pieces before; the fuselage is joined with the wings and landing gear and moves down the assembly line for the engine