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Topic Review
Deformable Mirror
Deformable mirrors (DM) are mirrors whose surface can be deformed, in order to achieve wavefront control and correction of optical aberrations. Deformable mirrors are used in combination with wavefront sensors and real-time control systems in adaptive optics. In 2006 they found a new use in femtosecond pulse shaping. The shape of a DM can be controlled with a speed that is appropriate for compensation of dynamic aberrations present in the optical system. In practice the DM shape should be changed much faster than the process to be corrected, as the correction process, even for a static aberration, may take several iterations. A DM usually has many degrees of freedom. Typically, these degrees of freedom are associated with the mechanical actuators and it can be roughly taken that one actuator corresponds to one degree of freedom.
  • 1.1K
  • 03 Nov 2022
Topic Review
List of Gliders (G)
This is a list of gliders/sailplanes of the world, (this reference lists all gliders with references, where available) Note: Any aircraft can glide for a short time, but gliders are designed to glide for longer.
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  • 09 Oct 2022
Topic Review
Bowdoin (Arctic Schooner)
The schooner Bowdoin /ˈboʊdɪn/ was designed by William H. Hand, Jr., and built in 1921, in East Boothbay, Maine, at the Hodgdon Brothers Shipyard now known as Hodgdon Yachts. She is the only American schooner built specifically for Arctic exploration, and was designed under the direction of explorer Donald B. MacMillan. She has made 29 trips above the Arctic Circle in her life, three since she was acquired by the Maine Maritime Academy in 1988. She is currently owned by the Maine Maritime Academy, located in Castine, Maine, and is used for their sail training curriculum. She is named for Bowdoin College.
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  • 17 Oct 2022
Topic Review
Plasma-Enhanced Chemical Vapor Deposition
Plasma-enhanced chemical vapor deposition (PECVD) is a chemical vapor deposition process used to deposit thin films from a gas state (vapor) to a solid state on a substrate. Chemical reactions are involved in the process, which occur after creation of a plasma of the reacting gases. The plasma is generally created by radio frequency (RF) (alternating current (AC)) frequency or direct current (DC) discharge between two electrodes, the space between which is filled with the reacting gases.
  • 1.1K
  • 18 Nov 2022
Biography
Jack Ridley (Pilot)
Colonel Jackie Lynwood "Jack" Ridley (June 16, 1915 – March 12, 1957) was an aeronautical engineer, USAF test pilot and chief of the U.S. Air Force's Flight Test Engineering Laboratory. He helped develop and test many Cold War era military aircraft. He worked on the Bell X-1, the first aircraft to achieve supersonic flight. He was highly respected among fellow test pilots, most notably Chuck Y
  • 1.1K
  • 23 Nov 2022
Topic Review
Perhapsatron
The Perhapsatron was an early fusion power device based on the pinch concept in the 1950s. Conceived by James (Jim) Tuck while working at Los Alamos National Laboratory (LANL), he whimsically named the device on the chance that it might be able to create fusion reactions. The first example was built in the winter of 1952/53, and it quickly demonstrated a series of instabilities in the plasma that plagued the pinch concept. A series of modifications followed which attempted to correct these problems, leading to the ultimate "S-4" model. None of these proved fruitful.
  • 1.1K
  • 27 Sep 2022
Topic Review
Blue Streak (Missile)
The de Havilland Propellers Blue Streak was a British medium-range ballistic missile (MRBM), and later the first stage of the Europa satellite launch vehicle. Blue Streak was cancelled without entering full production. The project was intended to maintain an independent British nuclear deterrent, replacing the V bomber fleet which would become obsolete by 1965. The operational requirement for the missile was issued in 1955 and the design was complete by 1957. However, during development it became clear that the missile system was too expensive and too vulnerable to a pre-emptive strike. The missile project was cancelled in 1960, with US-led Skybolt the preferred replacement. Partly to avoid political embarrassment from the cancellation, the UK Government proposed that the rocket be used as the first stage of a civilian satellite launcher called Black Prince. However, the cost was thought to be too great for the UK alone, and international collaboration was sought. This led to the formation of the European Launcher Development Organisation (ELDO), with Blue Streak used as the first stage of a carrier rocket named Europa. Europa was tested at Woomera Test Range, Australia, and later at Kourou in French Guiana. Following launch failures, the ELDO project was cancelled in 1972 and development of Blue Streak was halted.
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  • 11 Oct 2022
Topic Review
Time Stretch Analog-to-digital Converter
The time-stretch analog-to-digital converter (TS-ADC), also known as the time stretch enhanced recorder (TiSER), is an analog-to-digital converter (ADC) system that has the capability of digitizing very high bandwidth signals that cannot be captured by conventional electronic ADCs. Alternatively, it is also known as the photonic time stretch (PTS) digitizer, since it uses an optical frontend. It relies on the process of time-stretch, which effectively slows down the analog signal in time (or compresses its bandwidth) before it can be digitized by a slow electronic ADC.
  • 1.1K
  • 20 Oct 2022
Topic Review
Digital Storytelling in Education
Digital storytelling in education can be made possible by introducing user-friendly tools into the process, representing not just a fashion of the time but mostly a renewal trend, aiming at revitalizing the course to attract and engage learners. Undoubtedly, today’s pupils have grown up with technological means, becoming familiar with their use so their implication causes undiminished interest in most daily activities, including schooling. In this high-tech generation, it is absurd to address the transmission of knowledge and values in outdated ways. Apart from adapting to the timely students’ needs, lesson plans on transmedia storytelling practices can also satisfy tutors, triggering their inspiration and co-creation potentials.
  • 1.1K
  • 13 Sep 2022
Topic Review
Vintage Car
A vintage car is, in the most general sense, an old automobile, and in the narrower senses of car enthusiasts and collectors, it is a car from the period of 1919 to 1930. Such enthusiasts have categorization schemes for ages of cars that enforce distinctions between antique cars, vintage cars, classic cars, and so on. The classification criteria vary, but consensus within any country is often maintained by major car clubs.
  • 1.1K
  • 04 Nov 2022
Topic Review
Time Series Analysis
With the advent of the digital computer, time series analysis has gained wide attention and is being applied to many fields of science. In this survey entry, many traditional and recent techniques for time series analysis and change detection are reviewed, including spectral and wavelet analyses with their advantages and weaknesses. The main focus of the survey is the analysis of unevenly sampled or unequally spaced time series.
  • 1.0K
  • 07 Jul 2021
Biography
Henry P. Kendall
Henry Plimpton Kendall (January 15, 1878 – November 3, 1959) was a New England entrepreneur, industrialist, and philanthropist from Walpole, Massachusetts. He is considered one of the pioneers of scientific management.[1] Kendall was born in 1878 in Charlestown, Massachusetts, son of Henry Lucien Kendall en Clara Idella (Plimpton) Kendal. After attending the Lawrenceville School, boarding
  • 1.0K
  • 15 Dec 2022
Topic Review
Xiaomi Smart Home
Xiaomi Smart Home Products (also known as Mi Ecosystem products) are products released by third-party manufacturers who have partnered with Xiaomi. These products are managed by Mi Home app.
  • 1.0K
  • 22 Nov 2022
Biography
Philip G. Hubbard
Philip Gamaliel Hubbard, (March 4, 1921 - January 10, 2002) was a university professor and administrator who was the first African-American faculty member at the University of Iowa, the first African-American administrator at any of Iowa's state universities and the first African-American vice president at a Big 10 university. In August 2012 Hubbard was inducted into the Iowa African American Ha
  • 1.0K
  • 16 Dec 2022
Biography
Nils Otto Myklestad
Nils Otto Myklestad (March 24, 1909 – September 23, 1972) was an American mechanical engineer and engineering professor.[1] An authority on mechanical vibration, he was employed by a number of important US engineering firms and served on the faculty of several major engineering universities. Myklestad made significant contributions to both engineering practice and engineering education, publis
  • 1.0K
  • 15 Nov 2022
Biography
Torkel Korling
Torkel Korling (April 24, 1903 – October 22, 1998) was a Swedish-born American -, commercial, portrait and botanical photographer. Torkel Korling was born into a 400-year line of Lutheran Church choir directors and organists in Kristdala, Sweden. His father, Felix Körling, was first to find success beyond the church as a composer and conductor in Sweden. Korling set out to be a botanist. T
  • 1.0K
  • 13 Dec 2022
Topic Review
Diagnosis Application of MINI and BERT
Researchers propose a mental health diagnosis application for Arabic-speaking patients using both The MINI-International Neuropsychiatric Interview (MINI) and the supervised machine learning BERT model to equip the psychiatry department of the Military Hospital of Instruction of Tunis with a rapid and intelligent tool handling the high number of patients treated every day.
  • 1.0K
  • 29 Jan 2022
Topic Review
Distance Measuring Equipment (Aviation)
In aviation, distance measuring equipment (DME) is a radio navigation technology that measures the slant range (distance) between an aircraft and a ground station by timing the propagation delay of radio signals in the frequency band between 960 and 1215 megahertz (MHz). Line-of-visibility between the aircraft and ground station is required. An interrogator (airborne) initiates an exchange by transmitting a pulse pair, on an assigned 'channel', to the transponder ground station. The channel assignment specifies the carrier frequency and the spacing between the pulses. After a known delay, the transponder replies by transmitting a pulse pair on a frequency that is offset from the interrogation frequency by 63 MHz and having specified separation. DME systems are used worldwide, using standards set by the International Civil Aviation Organization (ICAO), RTCA, the European Union Aviation Safety Agency (EASA) and other bodies. Some countries require that aircraft operating under instrument flight rules (IFR) be equipped with a DME interrogator; in others, a DME interrogator is only required for conducting certain operations. While stand-alone DME transponders are permitted, DME transponders are usually paired with an azimuth guidance system to provide aircraft with a two-dimensional navigation capability. A common combination is a DME colocated with a VHF omnidirectional range (VOR) transmitter in a single ground station. When this occurs, the frequencies of the VOR and DME equipment are paired. Such a configuration enables an aircraft to determine its azimuth angle and distance from the station. A VORTAC (a VOR co-located with a TACAN) installation provides the same capabilities to civil aircraft but also provides 2-D navigation capabilities to military aircraft. Low-power DME transponders are also associated with some instrument landing system (ILS), ILS localizer and microwave landing system (MLS) installations. In those situations, the DME transponder frequency/pulse spacing is also paired with the ILS, LOC or MLS frequency. ICAO characterizes DME transmissions as ultra high frequency (UHF). The term L-band is also used. Developed in Australia, DME was invented by James "Gerry" Gerrand under the supervision of Edward George "Taffy" Bowen while employed as Chief of the Division of Radiophysics of the Commonwealth Scientific and Industrial Research Organisation (CSIRO). Another engineered version of the system was deployed by Amalgamated Wireless Australasia Limited in the early 1950s operating in the 200 MHz VHF band. This Australian domestic version was referred to by the Federal Department of Civil Aviation as DME(D) (or DME Domestic), and the later international version adopted by ICAO as DME(I). DME is similar in principle to secondary radar ranging function, except the roles of the equipment in the aircraft and on the ground are reversed. DME was a post-war development based on the identification friend or foe (IFF) systems of World War II. To maintain compatibility, DME is functionally identical to the distance measuring component of TACAN.
  • 1.0K
  • 14 Oct 2022
Biography
Ami Argand
François-Pierre-Amédée Argand, known as Ami Argand (5 July 1750 – 14[1] or 24 October 1803[2]) was a Genevan physicist and chemist. He invented the Argand lamp, a great improvement on the traditional oil lamp.[3] Francois-Pierre-Amédée Argand was born in Geneva, Switzerland, the ninth of ten children. His father was a watchmaker, who intended for him to enter the clergy. However, he ha
  • 1.0K
  • 01 Dec 2022
Biography
Rex Buren Beisel
Rex Buren Beisel (October 24, 1893 – January 26, 1972) was an American aeronautical engineer and pioneer in the science and industry of aviation. He was the lead designer of several successful military and civilian aircraft, but is best known for designing the Second World War-era Vought F4U Corsair fighter plane. Beisel was born on October 24, 1893, in San Jose, California,[1] and was rais
  • 1.0K
  • 16 Dec 2022
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