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Topic Review
Tensor Processing Unit
A tensor processing unit (TPU) is an AI accelerator application-specific integrated circuit (ASIC) developed by Google specifically for neural network machine learning, particularly using Google's own TensorFlow software. Google began using TPUs internally in 2015, and in 2018 made them available for third party use, both as part of its cloud infrastructure and by offering a smaller version of the chip for sale.
  • 1.0K
  • 18 Nov 2022
Biography
Thomas J.R. Hughes
Thomas Joseph Robert Hughes (born 1943) is a Professor of Aerospace Engineering and Engineering Mechanics and currently holds the Computational and Applied Mathematics Chair III in the Institute for Computational Engineering and Sciences at The University of Texas at Austin.[1][2] Hughes has been listed as an ISI Highly Cited Author in Engineering by the ISI Web of Knowledge, Thomson Scientific
  • 1.0K
  • 16 Nov 2022
Topic Review
Ionocraft
An ionocraft or ion-propelled aircraft (commonly known as a lifter or hexalifter) is a device that uses an electrical electrohydrodynamic (EHD) phenomenon to produce thrust in the air without requiring any combustion or moving parts. The term "ionocraft" dates back to the 1960s, an era in which EHD experiments were at their peak. In its basic form, it simply consists of two parallel conductive electrodes, one in the form of a fine wire and another which may be formed out of wire grid, tubes or foil skirts with a smooth round surface. When such an arrangement is powered by high voltage (in the range of a few kilovolts), it produces thrust. The ionocraft forms part of the EHD thruster family, but is a special case in which the ionisation and accelerating stages are combined into a single stage. The device is a popular science fair project for students. It is also popular among anti-gravity or so-called "electrogravitics" proponents, due to the research of Thomas Townsend Brown, who built these devices in the 1920s and incorrectly believed that he had found a way to modify gravity using electric fields. The term "lifter" is an accurate description because it is not an anti-gravity device; rather, it produces lift using the same basic principle as a rocket, i.e. from the equal but opposite force upward generated by the driving force downward, specifically by driving the ionized air downward in the case of the ionocraft. Much like a rocket or a jet engine (it can actually be much more thrust efficient than a jet engine), the force that an ionocraft generates is consistently oriented along its own axis, regardless of the surrounding gravitational field. Claims of the device also working in a vacuum have been disproved. Ionocraft require many safety precautions due to the high voltage required for their operation; nevertheless, a large subculture has grown up around this simple EHD thrusting device and its physics are now known to a much better extent.
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  • 01 Dec 2022
Topic Review
Tracking and Data Relay Satellite
File:TDRS Heart of Communication.ogv File:Tracking Data Relay Satellite (TDRS) Orbital Fleet Communicating with User Spacecraft.ogg File:Tracking Data Relay Satellite (TDRS) Orbital Fleet Communicating with User Spacecraft 2017 - 360 video.webm A tracking and data relay satellite (TDRS) is a type of communications satellite that forms part of the Tracking and Data Relay Satellite System (TDRSS) used by NASA and other United States government agencies for communications to and from independent "User Platforms" such as satellites, balloons, aircraft, the International Space Station, and remote bases like the Amundsen-Scott South Pole Station. This system was designed to replace an existing worldwide network of ground stations that had supported all of NASA's crewed flight missions and uncrewed satellites in low-Earth orbits. The primary system design goal was to increase the amount of time that these spacecraft were in communication with the ground and improve the amount of data that could be transferred. These TDRSS satellites are all designed and built to be launched to and function in geosynchronous orbit, 35,786 km (22,236 mi) above the surface of the Earth. The first seven TDRSS satellites were built by the TRW corporation. The three later versions have been manufactured by the Boeing corporation's Satellite Systems division. Thirteen satellites have been launched; however, one was destroyed in the Challenger disaster. TDRS-1 was decommissioned in October 2009. TDRS-4 was decommissioned in December 2011. Ten TDRSS satellites are currently in service. All of the TDRSS satellites have been managed by NASA's Goddard Space Flight Center. The contract for TDRS versions L & K was awarded to Boeing on December 20, 2007. On November 30, 2011, NASA announced the decision to order an additional third-generation TDRS satellite, TDRS M.
  • 1.0K
  • 04 Nov 2022
Topic Review
Visibility Enhancement and Fog Detection
In mobile systems, fog, rain, snow, haze, and sun glare are natural phenomena that can be very dangerous for drivers. In addition to the visibility problem, the driver must face also the choice of speed while driving. The main effects of fog are a decrease in contrast and a fade of color. Rain and snow cause also high perturbation for the driver while glare caused by the sun or by other traffic participants can be very dangerous even for a short period. In the field of autonomous vehicles, visibility is of the utmost importance. To solve this problem, different researchers have approached and offered varied solutions and methods. It is useful to focus on what has been presented in the scientific literature over the past ten years relative to these concerns. 
  • 1.0K
  • 28 May 2021
Topic Review
Optical Switch
An optical switch is a device that selectively switches optical signals from one channel to another. The switching can be temporal or spatial. The former is known as an optical (time-domain) switch or an optical modulator, while the latter is called an optical space switch or an optical router. In general, optical modulators and routers can be made from each other.
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  • 17 Oct 2022
Topic Review
AI in the Field of Surfactants
Artificial intelligence (AI) is increasingly being used in the field of surfactants to improve the efficiency, effectiveness, and sustainability of surfactant production and applications. One of the main applications of AI in surfactants is in the design and development of new surfactant molecules. By using machine learning algorithms and computational modeling, researchers can predict the properties and behavior of new surfactants before they are synthesized, reducing the time and cost required for research and development. AI is also being used to optimize surfactant production processes, by analyzing large amounts of data generated during production and identifying areas for improvement. For example, AI can be used to optimize surfactant synthesis conditions, such as temperature and pressure, to improve yield and reduce waste. In addition, AI is being used to develop predictive models for surfactant performance in specific applications, such as in the production of emulsions, foams, and coatings. By understanding the relationship between surfactant properties and application performance, researchers can design more effective and sustainable surfactant formulations.
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  • 24 Mar 2023
Topic Review
Wind Turbine Blades: End-of-Life Scenarios
Large expansion of wind energy is expected in next decades. At the same time, a significant proportion of the installed wind turbines, the generation installed in 2000s, will come to the end of their lifetime between 2020 and 2030. Many parts of wind turbines can be recycled, however, this is seldom the case for the composite wind blades. Wind turbine blades are developed and designed to sustain challenging service conditions and extraordinary mechanical and ennvironmental loads for several decades. Therefore, their afterlife destruction and separation into re-usable elements represents a challenge. In this review, strategies of end-of-life management of wind turbine blades are discussed. Various scenarios of end-of-life management of wind turbine blades are considered. “Reactive” strategies, designed to deal with ageing turbines, installed in 2000s, include improved maintenance and repair technologies, reuse, refurbishment and recycling.  “Pro-active strategies”, applicable to f new generations of wind turbines, include wind turbine blades with thermoplastic and recyclable thermoset composite matrices, as well as wood, bamboo and natural fiber based composites. 
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  • 23 Mar 2021
Topic Review
Flying Disc Games
Flying disc games are games played with discs, often called by the trademarked name Frisbees. Ultimate and disc golf are sports with substantial international followings.
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  • 24 Oct 2022
Topic Review
Intelligent Speed Adaptation
Intelligent speed adaptation (ISA), also known as alerting, and intelligent authority, is any system that ensures that vehicle speed does not exceed a safe or legally enforced speed. In case of potential speeding, a human driver can be alerted, or the speed reduced automatically. Intelligent speed adaptation uses information about the road to determine the required speed. Information can be obtained from knowledge of the vehicle position, taking into account speed limits known for the position, and by interpreting road features such as signs. ISA systems are designed to detect and alert a driver when a vehicle has entered a new speed zone, or when different speed limits are in force according to time of day and conditions. Many ISA systems also provide information about driving hazards (e.g. high pedestrian movement areas, railway crossings, schools, hospitals, etc.) and limits enforced by speed and CCTV cameras at traffic lights. The purpose of ISA is to assist the driver to maintain a safe speed. Research has found that, in urban areas, the number of crashes causing casualties is doubled for each 5 km/h (3.1 mph) over the limit.
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  • 27 Oct 2022
Topic Review
Piaget SA
Piaget SA (French pronunciation: ​[pja.ʒɛ]) is a Switzerland luxury watchmaker and jeweller. Founded in 1874 by Georges Piaget in the village of La Côte-aux-Fées, Piaget is currently a subsidiary of the Swiss Richemont group. Piaget was founded as a manufacturer of watch movements but began marketing its own line of watches in the 20th century.
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  • 01 Dec 2022
Topic Review
Leaching
Leaching is the process of a solute becoming detached or extracted from its carrier substance by way of a solvent. Leaching is a naturally occurring process which scientists have adapted for a variety of applications with a variety of methods. Specific extraction methods depend on the soluble characteristics relative to the sorbent material such as concentration, distribution, nature, and size. Leaching can occur naturally seen from plant substances (inorganic and organic), solute leaching in soil, and in the decomposition of organic materials. Leaching can also be applied affectedly to enhance water quality and contaminant removal, as well as for disposal of hazardous waste products such as fly ash, or rare earth elements (REEs). Understanding leaching characteristics is important in preventing or encouraging the leaching process and preparing for it in the case where it is inevitable. In an ideal leaching equilibrium stage, all the solute is dissolved by the solvent, leaving the carrier of the solute unchanged. The process of leaching however is not always ideal, and can be quite complex to understand and replicate, and often different methodologies will produce different results.
  • 1.0K
  • 15 Nov 2022
Biography
Percy Spencer
Percy Lebaron Spencer (July 19, 1894 – September 8, 1970) was an United States physicist and inventor. He became known as the inventor of the microwave oven.[1] Spencer was born in Howland, Maine. Eighteen months later, Spencer's father died, and his mother soon left him in the care of his aunt and uncle. His uncle then died when Spencer was just seven years old. Spencer subsequently left g
  • 1.0K
  • 27 Dec 2022
Biography
Clemens Herschel
Clemens Herschel (March 23, 1842 – March 1, 1930) was an American hydraulic engineer. His career extended from about 1860 to 1930, and he is best known for developing the Venturi meter, which was the first large-scale, accurate device for measuring water flow.[1][2] Clemens was born in Vienna in 1842. His family immigrated to Davenport, Iowa in 1850. He spent most of his life practicing his
  • 1.0K
  • 24 Nov 2022
Biography
Caroline Pratt
Caroline Pratt (May 13, 1867 – June 6, 1954[1] ) was an American social thinker and progressive educational reformer whose ideas were influential in educational reform, policy, and practice.[2] Pratt is known as the founder of City and Country School in the Greenwich Village section of the borough of Manhattan in New York City ; the inventor of unit blocks;[3][4][5] and as the author of I Le
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  • 01 Dec 2022
Topic Review
Toshiba Libretto
The Libretto was a line of subnotebook computers designed and produced by Toshiba. The line was distinguished by its combination of functionality and small size, squeezing a full Windows PC into a device the size of a paperback book. The first Libretto model, the Libretto 20, was released on April 17, 1996 (in Japan only), with a volume of 821 cm3 (50.1 cu in) and weighing just 840 g (30 oz), making it by far, the world's smallest commercially available Windows PC at the time, and a trend the Libretto Range continued for many years. The original Libretto line was discontinued in Europe and the U.S. in 1999, but the production continued in Japan with the SS, FF and then the L series until 2002. The first L series Libretto (The L1) was released on 18 May 2001 (in Japan only) and the last (The L5) just 11 Months later on 24 April 2002. Production of all Librettos ceased from 2002 until the release of the Libretto U100 in 2005. It was a further five years before the Libretto returned again in 2010 with the limited-edition dual touch screen tablet W100 model.
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  • 09 Oct 2022
Topic Review
Evolution of Access Network Sharing
Network sharing is part of a fundamental principle of statistical multiplexing of link capacity. Regardless of whether the nodes are setting up connections that reserve capacity in the Plain Old Telephone Service (POTS), or sending packets in a connection-less packet-switched network, the overall link capacity is only a fraction of the total interconnection capacity required if all nodes attempted communicating at once. Network sharing also applies to the progressive aggregation of link capacity where the ratio of multiplexing increases in moving from the access towards the core. From the mid-90s’, the concept of sharing was extended to also cover the multi-tenant use of the network, where third party network operators compete with the incumbent national operator, so that the same common infrastructure is shared across multiple competing entities. The degree to which infrastructure is shared is limited, on the one hand by physical and logical boundaries that separate resources, and on the other hand by economic complexities such as settlements, agreements and regulations that complicate the sharing process.
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  • 27 Oct 2020
Topic Review
Rikhter R-23
The Rikhter R-23 is an aircraft autocannon developed for the Soviet Air Force starting in the late 1950s. It was designed to be as short as possible to avoid problems found on high-speed aircraft when the guns were pointed into the airstream. The R-23 was a gas operated revolver cannon that used gas bled from holes in the barrel to provide the motive force. Firing up to 2,600 rpm, the R-23 was the fastest firing single-barrel cannon ever introduced into service. The R-23 took some time to develop, and was not used operationally until 1964. It was used only in the tail turret of the Tu-22, and experimentally on the Salyut 3 space station. Its role was taken over by the twin-barrel Gryazev-Shipunov GSh-23. A modified version of the weapon was the only cannon to have been fired in space.
  • 986
  • 08 Nov 2022
Topic Review
Manned Orbiting Laboratory
The Manned Orbiting Laboratory (MOL), originally referred to as the Manned Orbital Laboratory, was a never-flown part of the United States Air Force 's human spaceflight program, a successor to the canceled Boeing X-20 Dyna-Soar military reconnaissance space plane project. The project was developed from several early Air Force and NASA concepts of crewed space stations to be used for reconnaissance purposes. MOL evolved into a single-use laboratory, with which crews would be launched on 40-day missions and return to Earth using a Gemini B spacecraft, derived from NASA's Project Gemini. The MOL program was announced to the public on 10 December 1963 as an inhabited platform to prove the utility of putting people in space for military missions. Astronauts selected for the program were later told of the reconnaissance mission for the program. The contractor for the MOL was the Douglas Aircraft Company. The Gemini B was externally similar to NASA's Gemini spacecraft, although it underwent several modifications, including the addition of a circular hatch through the heat shield, which allowed passage between the spacecraft and the laboratory. MOL was canceled in 1969, during the height of the Apollo program, when it was shown that uncrewed reconnaissance satellites could achieve the same objectives much more cost-effectively. U.S. space station development was instead pursued with the civilian NASA Skylab (Apollo Applications Program) which flew in the mid-1970s. In the 1970s, the Soviet Union launched three Almaz military space stations, similar in intent to the MOL, but cancelled the program in 1977 for the same reasons. There is a MOL space suit on display at the Oklahoma City Science Museum, presumably never used.
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  • 11 Oct 2022
Topic Review
Ionic Liquids in DSSCs
The dye-sensitized solar cells (DSSCs) which are considered as the third-generation solar cells have a huge potential to be commercialized due to their low cost, simplicity in fabrication, and promising photon-to-electrical energy conversion efficiency. Nevertheless, a high cell efficiency can only be achieved when an organic solvent is incorporated into the formulation of the electrolyte, which is prone to evaporation and leakage. As a result, DSSCs become unsuitable for long-run usage due to thermal instability in the electrolyte. The early intention of incorporating ionic liquids (ILs) into the electrolyte was to curb the abovementioned problem and to enable the DSSCs to function as a sustainable energy device. ILs have been incorporated into the electrolyte formulation and the extent of how the ILs can affect the cell efficiency in various electrolyte states is highlighted. This sheds light on the true purpose of introducing ILs into DSSC electrolyte, which is to enhance the ionicity of the electrolyte.
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  • 26 Sep 2020
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