Portal:Technology
The Technology Portal
Technology is the application of conceptual knowledge to achieve practical goals, especially in a reproducible way. The word technology can also mean the products resulting from such efforts, including both tangible tools such as utensils or machines, and intangible ones such as software. Technology plays a critical role in science, engineering, and everyday life.
Technological advancements have led to significant changes in society. The earliest known technology is the stone tool, used during prehistoric times, followed by the control of fire, which contributed to the growth of the human brain and the development of language during the Ice Age. The invention of the wheel in the Bronze Age allowed greater travel and the creation of more complex machines. More recent technological inventions, including the printing press, telephone, and the Internet, have lowered barriers to communication and ushered in the knowledge economy. (Full article...)
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Entries here consist of Good and Featured articles, which meet a core set of high editorial standards.
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King's Highway 138, commonly referred to as Highway 138, is a provincially maintained highway in eastern Ontario, Canada. It extends from former Highway 2 in Cornwall, north to Highway 417 east of Casselman. Highway 138 provides access to the Seaway International Bridge, connecting Cornwall with Massena, New York. The highway is 38.7 km (24.0 mi) in length.
Highway 138 was first established in 1967, connecting Highway 2, now Vincent Massey Drive, with Highway 43 in Monkland. By the mid-1970s, the route had been extended north to meet with the newly opened Highway 417. Since then it has remained unchanged. (Full article...) -
The Belmont Park aviation meet was an international air show that took place in 1910. The Belmont Racetrack in Elmont, New York, United States, was the site of the aviation meet. The event took place over nine days and featured aerial races, and contests involving duration, distance, speed and altitude.
The show was managed and organized by the Aero Club of America and it took place over nine days, October 22–31, 1910. Featured aviators included Wilbur Wright, Alfred Leblanc, Émile Aubrun, René Simon, John Moisant and Claude Grahame-White. The show awarded prize money of US$72,300 (equivalent to $2,354,400 in 2023); revenue from gate gate receipts for the show totaled US$188,000 (equivalent to $6,147,600 in 2023). (Full article...)
Flag of convenience (FOC) is a business practice whereby a ship's owners register a merchant ship in a ship register of a country other than that of the ship's owners, and the ship flies the civil ensign of that country, called the flag state. The term is often used pejoratively, and although common, the practice is sometimes regarded as contentious.
Each merchant ship is required by international law to be registered in a registry created by a country, and a ship is subject to the laws of that country, which are used also if the ship is involved in a case under admiralty law. A ship's owners may elect to register a ship in a foreign country so as to avoid the regulations of the owners' country, which may, for example, have stricter safety standards. They may also select a jurisdiction to reduce operating costs, avoiding higher taxes in the owners' country and bypassing laws that protect the wages and working conditions of mariners. The term "flag of convenience" has been used since the 1950s. A registry which does not have a nationality or residency requirement for ship registration is often described as an open registry. Panama, for example, offers advantages such as easier registration (often online), the ability to employ cheaper foreign labour, and an exemption on income taxes. (Full article...)
The Coney Island–Stillwell Avenue station (also known as Coney Island Terminal and signed on some trains as either Coney Island or Stillwell Avenue) is a New York City Subway terminal in Coney Island, Brooklyn. It is the railroad-south terminus for the D, F, N, and Q trains at all times and for the <F> train during rush hours in the peak direction.
Coney Island–Stillwell Avenue has eight tracks and four island platforms, with trains entering from both compass north and south. Opened in 1919–1920, the large facility was designed at a time when Coney Island was the primary summer resort area for the New York metropolitan area, with all of the rail lines in southern Brooklyn funneling service to the area. The station has seen many service patterns throughout its history, and was completely renovated from 2001 to 2004. (Full article...)
Holland Village MRT station is an underground Mass Rapid Transit (MRT) station on the Circle line (CCL), located along the boundary of Bukit Timah and Queenstown planning areas in Singapore. Situated close to the junction of Holland Avenue and Holland Road, it primarily serves the area of Holland Village, where its name was derived from. The station is operated by SMRT Trains.
First announced as Holland MRT station in 2003, the station was renamed Holland Village through a public poll in 2005. The station opened on 8 October 2011 when Stages 4 and 5 of the CCL stations opened. The station features Holland Beat by Jeremy Sharma as part of the MRT network's Art-in-Transit programme. (Full article...)
In graph theory and graph algorithms, a feedback arc set or feedback edge set in a directed graph is a subset of the edges of the graph that contains at least one edge out of every cycle in the graph. Removing these edges from the graph breaks all of the cycles, producing an acyclic subgraph of the given graph, often called a directed acyclic graph. A feedback arc set with the fewest possible edges is a minimum feedback arc set and its removal leaves a maximum acyclic subgraph; weighted versions of these optimization problems are also used. If a feedback arc set is minimal, meaning that removing any edge from it produces a subset that is not a feedback arc set, then it has an additional property: reversing all of its edges, rather than removing them, produces a directed acyclic graph.
Feedback arc sets have applications in circuit analysis, chemical engineering, deadlock resolution, ranked voting, ranking competitors in sporting events, mathematical psychology, ethology, and graph drawing. Finding minimum feedback arc sets and maximum acyclic subgraphs is NP-hard; it can be solved exactly in exponential time, or in fixed-parameter tractable time. In polynomial time, the minimum feedback arc set can be approximated to within a polylogarithmic approximation ratio, and maximum acyclic subgraphs can be approximated to within a constant factor. Both are hard to approximate closer than some constant factor, an inapproximability result that can be strengthened under the unique games conjecture. For tournament graphs, the minimum feedback arc set can be approximated more accurately, and for planar graphs both problems can be solved exactly in polynomial time. (Full article...)
Trondheim Airport Station (IATA code: TRD), also known as Værnes Station (Norwegian: Værnes holdeplass), is a railway station located within the terminal complex of Trondheim Airport, Værnes in Stjørdal municipality in Trøndelag county, Norway. Situated on the Nordland Line, it serves both express trains and the Trøndelag Commuter Rail both operated by SJ Norge. The station was opened on 15 November 1994 along with a new terminal at the airport, making it the first airport rail link in the Nordic Countries. The station cost 24 million kr, and was built along the existing railway line. In each direction, the station handles one to two hourly commuter rail services, and three daily express services. Travel time to Trondheim is 38 minutes, while it is 9 hours and 5 minutes to Bodø. Access to the airport terminal is outdoors, but sheltered. (Full article...)
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The GameCube is a sixth generation video game console released by Nintendo beginning in 2001. Meant as a successor to the Nintendo 64, the GameCube sold approximately 22 million units worldwide. It was the third most-successful console of its generation, behind Sony's PlayStation 2 and Microsoft's Xbox. The GameCube was succeeded by the Wii in 2006. -
Photograph: NASAA self-portrait by the Mars rover Curiosity on October 31, 2012. The mosaic is stitched from a set of 55 images taken by the Mars Hand Lens Imager at "Rocknest," the spot in Gale crater where the mission's first scoop sampling took place. Self-portraits such as this help NASA document the state of the rover and track changes, such as dust accumulation and wheel wear. -
Image credit: Joaquim Alves GasparAn animation showing how to use a vernier caliper, which is a caliper that uses a vernier scale to interpolate linear measurements. Vernier calipers can measure internal and external dimensions using, respectively, the uppermost and lower jaws, and also depths, using the depth probe (located at the right end). In this example, the first two digits (2.4) are decided by the location of the zero of the vernier scale in the centimeter scale, and the last digit (0.07), by the first line of the vernier scale that exactly matches a line of the centimeter scale above. -
Photo: Bachrach Studios; Restoration: Michel VuijlstekeThomas Edison (1847–1931) was an American inventor, scientist and businessman who developed many devices that greatly influenced life around the world, including the phonograph, the motion picture camera, and a long-lasting, practical electric light bulb. Dubbed "The Wizard of Menlo Park" (now Edison, New Jersey) by a newspaper reporter, he was one of the first inventors to apply the principles of mass production and large teamwork to the process of invention, and therefore is often credited with the creation of the first industrial research laboratory. Edison is considered one of the most prolific inventors in history, holding 1,093 U.S. patents in his name, as well as many patents in the United Kingdom, France and Germany. -
Photo credit: Alfred T. Palmer"Big Pete" Ramagos, rigger at work on Douglas Dam, Tennessee, June 1942. A rigger is a person or company which specializes in the lifting and/or moving of extremely large and/or heavy objects. Riggers use equipment expressly designed for moving and lifting objects where ordinary material handling equipment cannot go. -
Image credit: Lewis HineA structural worker bolts beams on the framework during the construction of the Empire State Building in New York City. The 1,250-foot (380 m) building opened on May 1, 1931, at the time the tallest building in the world, overtaking the Chrysler Building (seen to the right), which had just been completed the year before. The addition of a pinnacle and antennas later increased its overall height to 1,472 feet (449 m). -
Photograph: NASATwo Jet Propulsion Laboratory engineers stand with three vehicles, providing a size comparison of three generations of Mars rovers. Front and center is the flight spare for the first Mars rover, Sojourner, which landed on Mars in 1997 as part of the Mars Pathfinder Project. On the left is a Mars Exploration Rover test vehicle, a working sibling to Spirit and Opportunity, which landed on Mars in 2004. On the right is a test rover for the Mars Science Laboratory, which landed Curiosity on Mars in 2012. -
Photograph credit: Michael MainieroThe SOCATA TBM (now Daher TBM) is a family of high-performance single-engine turboprop business and utility light aircraft manufactured by Daher. This SOCATA TBM 900 was photographed in flight during the 2015 EAA AirVenture Oshkosh airshow in the U.S. state of Wisconsin. The aircraft features a Pratt & Whitney Canada PT6A-64 engine, and a five-blade carbon-fiber propeller, which increases performance and decreases cabin noise. In a passenger configuration, the pressurized cabin is typically fitted with highly finished interiors, featuring luxury materials such as leather and wood veneers. -
Photograph: Julia Margaret Cameron; restoration: Adam CuerdenJohn Herschel was an English mathematician, astronomer, chemist, inventor, and experimental photographer. He named seven moons of Saturn and four moons of Uranus, invented the cyanotype and actinometer, and wrote extensively on topics including meteorology, physical geography and the telescope. -
Credit: Mike McGregorThe OLPC XO-1 is an inexpensive subnotebook laptop computer intended to be distributed to children in developing countries. -
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Photograph credit: Petar MiloševićA thermoplastic-sheathed cable consists of a toughened outer thermoplastic sheath of polyvinyl chloride, covering one or more individual annealed copper conductors. Each of the current-carrying conductors in the "core" is insulated by an individual thermoplastic sheath, coloured to indicate the purpose of the conductor concerned. The protective earth conductor may also be covered with insulation, although, in some countries, this conductor may be left as bare copper. The type of thermoplastic, the dimensions of the conductors and the colour of their individual insulation are specified by the regulatory bodies in the various countries concerned. -
A wheel is a circular component that is intended to rotate on an axial bearing. The wheel is one of the main components of the wheel and axle which is one of the six simple machines.
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Photo credit: Marshall Space Flight CenterA test firing of twin linear XRS-2200 aerospike engines, originally built for the Lockheed Martin X-33, a next-generation, commercially operated reusable launch vehicle. The aerospike engine is a type of rocket engine that maintains its efficiency across a wide range of altitudes through the use of an aerospike nozzle. A vehicle with an aerospike engine uses 25-30% less fuel at low altitudes, where most missions have the greatest need for thrust. -
An overhead power line is a structure used in electric power transmission and distribution to transmit electrical energy along large distances. It consists of one or more conductors suspended by towers or utility poles.
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Photograph: NACAKitty Joyner (1916–1993) was an American electrical engineer with the National Advisory Committee for Aeronautics (NACA), and then the National Aeronautics and Space Administration (NASA). She was hired in 1939 as the organization's first woman engineer, shortly after she had become the first woman to graduate from the University of Virginia's engineering program. -
Credit: Berthold WernerA telephone, or phone, is a telecommunications device that converts sound, typically the human voice, into electronic signals suitable for transmission via cables or other transmission media over long distances through satellite. -
Diagram: H Padleckas and Ju gatsu mikkaA diagram showing a side and underside view of an 18-wheeler semi-trailer truck with an enclosed cargo space. The underside view shows the arrangement of the wheels, and in blue, the axles, drive shaft, and differentials.
The numbered parts are:
'"`UNIQ--templatestyles-00000019-QINU`"'
#tractor unit
#semi-trailer (detachable)
#engine compartment
#cabin
#sleeper (not present in all trucks)
#air dam
#fuel tanks
#fifth-wheel coupling
#enclosed cargo space
#landing gear (legs for when semi-trailer is detached)
#tandem axles -
Photo credit: HeptagonA multiple exposure composite image of the implosion of a chimney at the former brewery "Henninger" in Frankfurt am Main, Germany. This controlled demolition technique involves strategically placing explosive material and timing its detonation so that a structure collapses on itself in a matter of seconds, minimizing the physical damage to its immediate surroundings. -
Daguerreotype credit: UnknownA daguerreotype from the 1850s of the Ben Campbell, a paddle steamer—a ship or boat driven by a steam engine that uses one or more paddle wheels to develop thrust for propulsion. The paddle wheel was the first form of mechanical propulsion for a boat, but has now been almost entirely superseded by more modern forms of marine propulsion.
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