You're using an outdated browser. Please upgrade to a modern browser for the best experience.
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 by:
Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)
Filter:
All Topic Review Biography Peer Reviewed Entry Video Entry
Topic Review
LAV (Armoured Vehicle)
The Light Armoured Vehicle (LAV) is a series of armoured vehicles built by General Dynamics Land Systems – Canada (GDLS-C), a London, Ontario-based subsidiary of General Dynamics. It is a license-produced version of the Mowag Piranha. The LAV family came about from the Armoured Vehicle General Purpose (AVGP) requirement of the Canadian Army. The first generation of LAV was created by Mowag for the Armoured Vehicle General Purpose (AVGP) requirement of the Canadian Army. This was a 6x6 variant of the Piranha I produced by General Motors Diesel in London, Ontario. Since entering service in 1976, it has undergone a number of upgrades. The LAV II introduced the now-familiar 8x8 configuration. The LAV continues to form the backbone of the Canadian Army's combat vehicle fleet. The LAV series of vehicles exist in a number of different variants and are used in a number of different roles such as armoured personnel carriers, engineering vehicles, command posts, ambulances and armoured recovery vehicles.
  • 5.4K
  • 21 Nov 2022
Topic Review
Adjustable-Speed Drive
Adjustable speed drive (ASD), also known as variable-speed drive (VSD), describes equipment used to control the speed of machinery. Many industrial processes such as assembly lines must operate at different speeds for different products. Where process conditions demand adjustment of flow from a pump or fan, varying the speed of the drive may save energy compared with other techniques for flow control. Where speeds may be selected from several different pre-set ranges, usually the drive is said to be adjustable speed. If the output speed can be changed without steps over a range, the drive is usually referred to as variable speed. Adjustable and variable speed drives may be purely mechanical (termed variators), electromechanical, hydraulic, or electronic.
  • 5.4K
  • 10 Nov 2022
Biography
K. Eric Drexler
Kim Eric Drexler (born April 25, 1955) is an American engineer best known for popularizing the potential of molecular nanotechnology (MNT), from the 1970s and 1980s. His 1991 doctoral thesis at Massachusetts Institute of Technology was revised and published as the book Nanosystems: Molecular Machinery Manufacturing and Computation (1992), which received the Association of American Publishers awa
  • 5.3K
  • 18 Nov 2022
Topic Review
Possessions of Muhammad
The possessions of the Islamic prophet Muhammad are a group of his items and possessions such as weapons, animals and others known with unique names. There is doubt about the attribution of these possessions to Muhammad, as many of them were lost during wars and tribulations. The scholar Ahmed Taymour says - after listing the remnants attributed to Muhammad in Constantinople (later Istanbul): "It is no secret that some of these remnants are likely to be true. However, we did not see any of the trustworthy people who mentioned it with proof or denial, for Allah (God), Glory be to Him, who knows about it best, and some of them cannot conceal what the idea or notion that stumbles on of suspicion and disputes it in doubts." The emir Ahmad Ibn Tulun mentioned in his book “Mufākahat al-Khullān fī Hawādith Az-Zamān”, in the incidents of the year 19 AH (640 CE) and 900 AH (1500 CE) that some claimed that they had a mug and some crutches of Muhammad and that “it was found that they are not of the possessions of the Prophet Muhammad, but rather they are the fragments of Al-Layth ibn Sa'd." The scholar Al-Suyuti said, on the authority of Muhammad (his garment): "This (the possessions) was used by the caliphs to inherit it and put it on their shoulders in processions sitting and riding, and it was on the able-bodied when he was killed and contaminated with blood, and I think it was lost in the temptation of the Tatars, for we belong to Allah (God) and to Him we shall return."
  • 5.3K
  • 11 Nov 2022
Topic Review
Spray freeze-drying in pharmaceutical products
Pharmaceutical manufacturing is evolving from traditional batch processes to continuous ones. The present review deals with the most recent technologies, based on spray freeze-drying, that can achieve this objective. It provides a comprehensive overview of the physics behind this process and of the most recent equipment design.
  • 5.3K
  • 27 Oct 2020
Topic Review
P5 (Microarchitecture)
The original Pentium microprocessor was introduced by Intel on March 22, 1993. It was instruction set compatible with the 80486 but was a new and very different microarchitecture design. The P5 Pentium was the first superscalar x86 microarchitecture and the world’s first superscalar microprocessor to be in mass production. It included dual integer pipelines, a faster floating-point unit, wider data bus, separate code and data caches as well as many other techniques and features to enhance performance and support security, encryption, and multiprocessing for workstations and servers. Considered the fifth main generation in the 8086 compatible line of processors, its implementation and microarchitecture was called P5. As with all new processors from Intel since the Pentium, some new instructions were added to enhance performance for specific types of workloads. The Pentium was the first Intel x86 to build in robust hardware support for multiprocessing similar to that of large IBM mainframe computers. Intel worked closely with IBM to define this capability and then Intel designed it into the P5 microarchitecture. This new capability was not present in prior x86 generations or x86 copies from competitors. In order to realize its greatest potential, compilers had to be optimized to take advantage of the instruction level parallelism provided by the new superscalar dual pipelines and applications needed to be recompiled. Intel spent substantial effort and resources working with development tool vendors, and major ISV and OS companies to optimize their products for Pentium prior to product launch. In October 1996, the similar Pentium MMX was introduced, complementing the same basic microarchitecture with the MMX instruction set, larger caches, and some other enhancements. Competitors included Motorola 68040, Motorola 68060, PowerPC 601, SPARC, MIPS, Alpha families, most of which also used a superscalar in-order dual instruction pipeline configuration at some time. Intel discontinued the P5 Pentium processors (sold as a cheaper product since the Pentium II of 1997) in early 2000 in favor of the Celeron processor, which had also replaced the 80486 brand.
  • 5.2K
  • 06 Oct 2022
Topic Review
Engine Control Unit
An engine control unit (ECU), also commonly called an engine control module (ECM) is a type of electronic control unit that controls a series of actuators on an internal combustion engine to ensure optimal engine performance. It does this by reading values from a multitude of sensors within the engine bay, interpreting the data using multidimensional performance maps (called lookup tables), and adjusting the engine actuators. Before ECUs, air–fuel mixture, ignition timing, and idle speed were mechanically set and dynamically controlled by mechanical and pneumatic means. If the ECU has control over the fuel lines, then it is referred to as an electronic engine management system (EEMS). The fuel injection system has the major role of controlling the engine's fuel supply. The whole mechanism of the EEMS is controlled by a stack of sensors and actuators.
  • 5.2K
  • 14 Oct 2022
Topic Review
SCMaglev
The SCMaglev (superconducting maglev, formerly called the MLU) is a magnetic levitation (maglev) railway system developed by Central Japan Railway Company (JR Central) and the Railway Technical Research Institute. On 21 April 2015, a manned seven-car L0 Series SCMaglev train reached a speed of 603 km/h (375 mph), less than a week after the same train clocked 590 km/h (370 mph), breaking the previous land speed record for rail vehicles of 581 km/h (361 mph) set by a JR Central MLX01 maglev train in December 2003.
  • 5.2K
  • 20 Oct 2022
Topic Review
Devices Using Qualcomm Snapdragon Systems-on-Chip
This is a list of devices using Qualcomm Snapdragon chips. Snapdragon is a family of mobile system on a chip (SoC) made by Qualcomm for use in smartphones, tablets, and smartbook devices.
  • 5.1K
  • 07 Nov 2022
Topic Review
List of Intel Pentium 4 Microprocessors
The Pentium 4 microprocessor from Intel is a seventh-generation CPU targeted at the consumer market.
  • 5.0K
  • 02 Oct 2022
Topic Review
BM-30 Smerch
The BM-30 Smerch (Russian: Смерч, "tornado", "whirlwind"), 9K58 Smerch or 9A52-2 Smerch-M is a Soviet heavy multiple rocket launcher. The system is intended to defeat personnel, armored, and soft targets in concentration areas, artillery batteries, command posts and ammunition depots. It was designed in the early 1980s and entered service in the Soviet Army in 1989. When first observed by the West in 1983, it received the code MRL 280mm M1983. It is expected to be superseded by the 9A52-4 Tornado.
  • 5.0K
  • 15 Nov 2022
Topic Review
Energy Technology
Energy technology is an interdisciplinary engineering science having to do with the efficient, safe, environmentally friendly, and economical extraction, conversion, transportation, storage, and use of energy, targeted towards yielding high efficiency whilst skirting side effects on humans, nature, and the environment. For people, energy is an overwhelming need, and as a scarce resource, it has been an underlying cause of political conflicts and wars. The gathering and use of energy resources can be harmful to local ecosystems and may have global outcomes. Energy is also the capacity to do work. We can get energy from food. Energy can be of different forms such as kinetic, potential, mechanical, heat, light etc. Energy is required for individuals and the whole society for lighting, heating, cooking, running, industries, operating transportation and so forth. Basically there are two types of energy depending on the source s they are; 1.Renewable Energy Sources 2.Non-Renewable Energy Sources
  • 5.0K
  • 11 Nov 2022
Topic Review
Sabot
A sabot (UK: /sæˈboʊ, ˈsæboʊ/, US: /ˈseɪboʊ/) is a structural device used in firearm or cannon ammunition to keep a sub-caliber flight projectile, such as a relatively small bullet or arrow-type projectile, in the center of the barrel when fired, if the bullet has a significantly smaller diameter than the bore diameter of the weapon used. The sabot component in projectile design is more than simply the relatively thin, tough and deformable seal known as a driving band or obturation ring needed to trap propellant gases behind a projectile, and also keep the projectile centered in the barrel, when the outer shell of the projectile is only slightly smaller in diameter than the caliber of the barrel. Driving bands and obturators are used to seal these full-bore projectiles in the barrel because of manufacturing tolerances; there always exists some gap between the projectile outer diameter and the barrel inner diameter, usually a few thousandths of an inch; enough of a gap for high pressure gasses to slip by during firing. Driving bands and obturator rings are made from material that will deform and seal the barrel as the projectile is forced from the chamber into the barrel. Small caliber jacketed bullets do not normally employ driving bands or obturators because the jacket material, for example copper or gilding metal, is deformable enough to serve that function, and the bullet is made slightly larger than the barrel for that purpose, (see full metal jacket bullet and driving band). Sabots certainly use driving bands and obturators, because the same manufacturing tolerance issues exist when sealing the saboted projectile in the barrel, but the sabot itself is a more substantial structural component of the in-bore projectile configuration (Drysdale 1978). Refer to the two APFSDS (armor-piercing fin-stabilized discarding sabot) pictures on the right to see the substantial material nature of a sabot to fill the bore diameter around the sub-caliber arrow-type flight projectile, compared to the very small gap sealed by a driving band or obturator to mitigate what is known classically as windage. More detailed cutaways of the internal structural complexity of advanced APFSDS saboted long rod penetrator projectiles can be found at reference 2.
  • 5.0K
  • 27 Oct 2022
Topic Review
Primitive Clay Oven
The primitive clay oven, or earthen oven / cob oven, has been used since time immemorial by diverse cultures and societies, primarily for, but not exclusive to, baking before the invention of cast-iron stoves, and gas and electric ovens. The general build and shape were, mostly, common to all peoples, with only slight variations in size and in materials used to construct the oven. In primitive courtyards and farmhouses, earthen ovens were built on the ground. In Arabian, Palestinian, Middle-Eastern and North-African societies, bread was often baked within a clay oven called in some Arabic dialects a tabun (also transliterated taboon, from the Arabic: طابون), or else in a clay oven called a tannour, and in other dialects mas'ad. The clay oven, synonymous with the Hebrew word tannour (= oven), was shaped like a truncated cone, with an opening either at the top or bottom from which to stoke the fire. Others were made cylindrical with an opening at the top. Built and used in biblical times as the family, neighbourhood, or village oven, clay ovens continue to be made in parts of the Middle East today.
  • 4.9K
  • 22 Nov 2022
Topic Review
Gyro-Stabilized Camera Systems
Gyro-stabilized camera systems use modern electronic position data to correct for movements of the platforms they are mounted on to enable a high degree of stabilization. The systems often use a multi-axis gyro stabilization to enable the use of zoom lenses and high definition capture, despite the high amounts of vibrations and movements in aircraft, helicopters or other vehicles. The applications range from security and military operations, law enforcement, ENG, sports broadcasting documentary, natural history, and feature film productions..
  • 4.9K
  • 14 Oct 2022
Biography
Anousheh Ansari
Anousheh Ansari (Persian: Anuŝe Ansāri‎; née Raissyan;[1] born September 12, 1966) is an Iranian-American engineer and co-founder and chairwoman of Prodea Systems. Her previous business accomplishments include serving as co-founder and CEO of Telecom Technologies, Inc. (TTI). The Ansari family is also the title sponsor of the Ansari X Prize. On September 18, 2006, a few days after her 40th
  • 4.9K
  • 17 Nov 2022
Topic Review
Smart City Planning
The smart city concept is established as those “cities with an intelligent economic, institutional, social and physical infrastructure, which ensure the centralization of their citizens in a sustainable environment”, this being a great challenge to achieve.
  • 4.8K
  • 06 Jun 2021
Topic Review
U-Boat Campaign (World War I)
The U-boat Campaign from 1914 to 1918 was the World War I naval campaign fought by German U-boats against the trade routes of the Allies. It took place largely in the seas around the British Isles and in the Mediterranean. The German Empire relied on imports for food and domestic food production (especially fertilizer) and the United Kingdom relied heavily on imports to feed its population, and both required raw materials to supply their war industry; the powers aimed, therefore, to blockade one another. The British had the Royal Navy which was superior in numbers and could operate on most of the world's oceans because of the British Empire, whereas the Imperial German Navy surface fleet was mainly restricted to the German Bight, and used commerce raiders and unrestricted submarine warfare to operate elsewhere. In the course of events in the Atlantic alone, German U-boats sank almost 5,000 ships with nearly 13 million gross register tonnage, losing 178 boats and about 5,000 men in combat. Other naval theatres saw U-boats operating in both the Far East and South East Asia, the Indian Ocean and the Mediterranean and North Seas.
  • 4.8K
  • 06 Dec 2022
Topic Review
North–South Commuter Railway
The North–South Commuter Railway (NSCR), also known as the Clark–Calamba Railway, is a 148 km (92 mi) urban rail transit line being constructed in Luzon. It will run from New Clark City in Capas, Tarlac to Calamba, Laguna with 36 stations, with historic stations to be restored. Originally planned in the 1990s, the project has been repetitively halted after disagreements on funding and allegations of overpricing. The first proposal was the 32 km (20 mi) "Manila–Clark rapid railway" with Spain, and during the 2000s, the NorthRail project with China that was discontinued in 2011. The present line is under the Duterte administration and is to be aided with Japanese financing. It was initially reported to have a total length of 180 km (110 mi), though it was reduced to 148 kilometers (92 mi) after a segment to Los Baños was scrapped. The railway system is expected to cost ₱777.55 billion (US$14.95 billion), making it one of the most expensive projects of the Build! Build! Build! Infrastructure Program. Partial operations will begin by 2021, and full operations is expected to begin by 2025. The NSCR will comprise two sections corresponding to the Philippine National Railways' old main lines; the 91 km (57 mi) fully-elevated NSCR North which is being built over the mostly-defunct North Main Line in northern Metro Manila and Central Luzon, and the 56 km (35 mi) NSCR South which will use the existing PNR Metro Commuter Line infrastructure between Tutuban and Calamba, which were historically parts of the South Main Line and will have elevated, at-grade and depressed sections. The project's construction is divided into three phases with the NSCR North being separated between the 38 km (24 mi) NSCR North 1 commuter line between Tutuban and Malolos, and the 53 kilometres (33 mi) NSCR North 2 regional line from Malolos to New Clark City. It will also be linked to existing and future railway lines such as Line 8, Line 9, the Calamba–Bicol South Main Line and Calamba–Batangas City Railway.
  • 4.8K
  • 09 Oct 2022
Topic Review
Fountain (Duchamp)
Fountain is a readymade sculpture produced by Marcel Duchamp in 1917: a porcelain urinal signed "R.Mutt". In April 1917, an ordinary piece of plumbing chosen by Duchamp was rotated 90 degrees on its axis and submitted for an exhibition of the Society of Independent Artists, the first annual exhibition by the Society to be staged at The Grand Central Palace in New York. Fountain was not rejected by the committee but it was removed from the show area, since Society rules stated that all works would be accepted from artists who paid the fee. Following that removal, Fountain was photographed at Alfred Stieglitz's studio, and the photo published in The Blind Man. The original has been lost. The work is regarded by art historians and theorists of the avant-garde as a major landmark in 20th-century art. Sixteen replicas were commissioned by Duchamp in the 1950s and 1960s and made to his approval. Some scholars have suggested that the original work was by a female artist rather than Duchamp, but this is a minority view among historians.
  • 4.8K
  • 28 Nov 2022
  • Page
  • of
  • 50
Academic Video Service