Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort:
Hottest Latest Alphabetical (A-Z) Alphabetical (Z-A)
Type:
All Topic Review Biography
Topic Review
Actor
An actor or actress is a person who portrays a character in a performance. The actor performs "in the flesh" in the traditional medium of the theatre or in modern media such as film, radio, and television. The analogous Greek term is ὑποκριτής (Script error: No such module "Ancient Greek".), literally "one who answers". The actor's interpretation of a role—the art of acting—pertains to the role played, whether based on a real person or fictional character. This can also be considered an "actor's role," which was called this due to scrolls being used in the theaters. Interpretation occurs even when the actor is "playing themselves", as in some forms of experimental performance art. Formerly, in Ancient Greece and the medieval world, and in England at the time of William Shakespeare, only men could become actors, and women's roles were generally played by men or boys. While Ancient Rome did allow female stage performers, only a small minority of them were given speaking parts. The commedia dell’arte of Italy, however, allowed professional women to perform early on; Lucrezia Di Siena, whose name is on a contract of actors from 10 October 1564, has been referred to as the first Italian actress known by name, with Vincenza Armani and Barbara Flaminia as the first primadonnas and the first well-documented actresses in Italy (and in Europe). After the English Restoration of 1660, women began to appear onstage in England. In modern times, particularly in pantomime and some operas, women occasionally play the roles of boys or young men.
  • 949
  • 02 Oct 2022
Topic Review
AI Mk. VIII Radar
Radar, Airborne Interception, Mark VIII, or AI Mk. VIII for short, was the first operational microwave-frequency air-to-air radar. It was used by Royal Air Force night fighters from late 1941 until the end of World War II. The basic concept, using a moving parabolic antenna to search for targets and track them accurately, remained in use by most airborne radars well into the 1980s. Low-level development began in 1939 but was greatly sped after the introduction of the cavity magnetron in early 1940. This operated at 9.1 cm wavelength (3 GHz), much shorter than the 1.5 m wavelength of the earlier AI Mk. IV. Shorter wavelengths allowed it to use smaller and much more directional antennas. Mk. IV was blinded by the reflections off the ground from its wide broadcast pattern, which made it impossible to see targets flying at low altitudes. Mk. VIII could avoid this by keeping the antenna pointed upward, allowing it to see any aircraft at or above the horizon. The design was just beginning to mature in late 1941 when the Luftwaffe began low-level attacks. A prototype version, the Mk. VII, entered service on the Bristol Beaufighter in November 1941. A small number of these were sent to units across the UK to provide coverage at low altitudes while Mk. IV equipped aircraft operated at higher altitudes. After a small run of the improved Mk. VIIIA, the definitive Mk. VIII arrived in early 1942, offering higher power as well as a host of electronic and packaging upgrades. It arrived just as production rates of the De Havilland Mosquito began to improve, quickly displacing the Beaufighter units in RAF squadrons. Mk. VIII equipped Mosquitoes would be the premier night fighter from 1943 through the rest of the war. The Mk. VIII spawned a number of variants, notably the AI Mk. IX which included a lock-on feature to ease interceptions. A series of events, including a deadly friendly fire incident, so greatly delayed the Mk. IX that it never entered service. During the late-war period, many UK aircraft adopted the US SCR-720 under the name AI Mk. X. This worked on the same general principles as the Mk. VIII, but used a different display system that offered several advantages. Development of the basic system continued, and the Mk. IX would eventually briefly re-appear in greatly advanced form as the AI.17 during the 1950s.
  • 997
  • 16 Nov 2022
Topic Review
AKG
AKG Acoustics (originally Akustische und Kino-Geräte Gesellschaft m.b.H., English: Acoustic and Cinema Equipment L.L.C.) is an acoustics engineering and manufacturing company. It was founded in 1947 by Dr. Rudolf Görike and Ernest Plass in Vienna, Austria. It is a part of Harman International Industries, a subsidiary of Samsung Electronics. The products currently marketed under the AKG brand mostly consist of microphones, headphones, wireless audio systems and related accessories for professional and consumer markets.
  • 658
  • 20 Oct 2022
Topic Review
Allying Meta-Structures with Diverse Optical Waveguides for Integrated-Photonics
Recent years have witnessed tremendous interest in synergizing various functional subwavelength structures into diverse optical waveguide platforms to enable versatile photonic meta-devices. The advancement of meta-waveguides not only extends meta-optics into the manipulation of guided wave, but may also reshape the landscapes of photonic integrated circuits and massive emergent applications. A recent review paper outlined latest progress on meta-waveguides-based photonics devices and systems. Both forward and inverse designed scenarios are cataloged showcasing vibrant opportunities.
  • 1.0K
  • 13 Dec 2021
Topic Review
American International Health Alliance
American International Health Alliance (AIHA) is a nonprofit organisation aiming for assisting the global health. The organisation has managed more than 175 partnerships and project across the globe. In 2012, AIHA obtained the support of President's Emergency Plan for AIDS Relief [PEPFAR] project  to strengthen the blood service in Central Asia, Ukraine, and Cambodia. Due to its structure based on the programmatic modal and dynamic condition, this organisation is suitable to assist the community or worldwide countries which have limited resources, and it is beneficial for sustainable evolution. AIHA is contributing to improve the worldwide health conditions. This organisation has been associated and largely contributed in the HIV-related area since 2000.
  • 258
  • 14 Nov 2022
Topic Review
Animated Cartoon
An animated cartoon is a film for the cinema, television or computer screen, which is made using sequential drawings, as opposed to animation in general, which include films made using clay, puppets, 3D modeling and other means. Animated cartoons are still created for entertainment, commercial, educational and personal purposes.
  • 754
  • 18 Nov 2022
Topic Review
Anomaly Detection Algorithms for LAN Failure Prediction
Predicting Local Area Network (LAN) equipment failure is of utmost importance to ensure the uninterrupted operation of modern communication networks. The utilization of machine learning algorithms, specifically decision trees and support vector machines (SVMs), for predicting LAN failures represents a groundbreaking approach in network management.
  • 190
  • 13 Oct 2023
Topic Review
Antenna Aperture
In electromagnetics and antenna theory, antenna aperture, effective area, or receiving cross section, is a measure of how effective an antenna is at receiving the power of electromagnetic radiation (such as radio waves). The aperture is defined as the area, oriented perpendicular to the direction of an incoming electromagnetic wave, which would intercept the same amount of power from that wave as is produced by the antenna receiving it. Assume a plane wave in a particular direction has an irradiance or power flux density [math]\displaystyle{ S }[/math]; this is the amount of power passing through a unit area of one square meter. Then if an antenna delivers [math]\displaystyle{ P_o }[/math] watts to the load connected to its output terminals (e.g. the receiver) when irradiated by a uniform field of power density [math]\displaystyle{ S }[/math] watts per square meter, the antenna's aperture for the direction of that plane wave is [math]\displaystyle{ A_e }[/math] in square meters, given by: So the power received by an antenna (in watts) is equal to the power density of the electromagnetic energy (in watts per square meter), multiplied by its aperture (in square meters). Radio waves from a direction where the antenna's aperture is larger thus collect a greater amount of that wave's power; this is more often referred to as antenna gain. To actually obtain that available power [math]\displaystyle{ P_o }[/math], the incoming radiation must be in the state of polarization specified for that antenna, and the load (receiver) must be impedance matched to the antenna's feedpoint impedance. The meaning of aperture is thus based on a receiving antenna, however any receiving antenna can also be used for transmission. Due to reciprocity, an antenna's gain in receiving and transmitting are identical, so the power transmitted by an antenna in different directions (the radiation pattern) is always proportional to the effective area [math]\displaystyle{ A_e }[/math] in each direction; that proportionality factor is derived below. When no direction is specified, [math]\displaystyle{ A_e }[/math] (or "antenna gain") is understood to refer to its maximum value, that is, in the intended direction(s) that the antenna is designed to receive from and/or transmit toward.
  • 6.9K
  • 27 Oct 2022
Topic Review
Antenna Interface Standards Group
The Antenna Interface Standards Group (commonly referred to as AISG) is a non-profit international consortium formed by collaboration between communication infrastructure manufacturers and network operators with the purpose of maintaining and developing a standard for digital remote control and monitoring of antenna line devices in the wireless industry. The consortium was established in November 2001 with five original members, and as of March 2019 had 45 worldwide members based in North America, Asia, Europe, and the South Pacific. The consortium has released four versions of its base communication standard, AISG v1.0, AISG v1.1, AISG v2.0 and AISG v3.0. The consortium has also released stand alone standards that specify details related to its base standard. These standards include a standard for the connector used in AISG RS-485 based bus, standard for RF connector markings on the antenna faceplate and standards for distributing software and configuration files wrapped in XML. All published AISG standards can be downloaded from the AISG webpage.
  • 340
  • 17 Oct 2022
Topic Review
Apple Bandai Pippin
The Apple Bandai Pippin, stylized PiP P!N, is a multimedia technology console, designed by Apple Computer. The console is based on the Apple Pippin platform – a derivative of the Apple Macintosh platform. Bandai produced the ATMARK and @WORLD consoles between 1996 and 1997. It was sold at $599. The goal of the Bandai Pippin was to create an inexpensive computer system aimed mostly at playing CD-based multimedia software, especially games, but also functioning as a thin client. The operating system is a version of System 7.5.2, and is based on a 66 MHz PowerPC 603 processor and a 14.4 kb/s modem. It features a 4×-speed CD-ROM drive and a video output that can connect to a standard television display.
  • 1.1K
  • 27 Oct 2022
  • Page
  • of
  • 21
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of Social Sciences
Encyclopedia of COVID-19
Encyclopedia of Fungi
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Feedback