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
Military Transport Aircraft
Military transport aircraft or military cargo aircraft are typically fixed wing and rotary wing cargo aircraft which are used to airlift troops, weapons and other military equipment by a variety of methods to any area of military operations around the surface of the planet, usually outside the commercial flight routes in uncontrolled airspace. Originally derived from bombers, military transport aircraft were used for delivering airborne forces during World War II and towing military gliders. Some military transport aircraft are tasked to perform multi-role duties such as aerial refueling and, rescue missions, tactical, operational and strategic airlifts onto unprepared runways, or those constructed by engineers.
  • 1.6K
  • 20 Oct 2022
Topic Review
Ground Autonomous Vehicles for Agriculture
The available autonomous ground platforms developed by universities and research groups that were specifically designed to handle agricultural tasks was performed. As cost reduction and safety improvements are two of the most critical aspects for farmers, the development of autonomous vehicles can be of major interest, especially for those applications that are lacking in terms of mechanization improvements.
  • 1.6K
  • 22 Aug 2022
Topic Review
Plug-in Electric Vehicles in Japan
The fleet of light-duty plug-in electric vehicles in Japan totaled about 303,000 highway legal plug-in electric vehicles in circulation at the end of 2019, consisting of 152,320 all-electric passenger cars, 141,680 plug-in hybrids, and 8,720 light-commercial vehicles. The rate of growth of the Japanese plug-in segment slowed from 2013, with annual sales falling behind Europe, the U.S. and China since then. The segment market share fell from 0.68% in 2014 to 0.59% in 2016. Then the market share increased to 1.2% in 2017, and fell to 1.1% in 2018, and to 0.9% in 2019. Norway surpassed Japan as the country with the third largest plug-in car stock in use in 2019. The decline in plug-in car sales reflects the Japanese government and the major domestic carmakers decision to adopt and promote hydrogen fuel cell vehicles instead of plug-in electric vehicles, although the first commercially produced hydrogen fuel cell automobiles began in 2015. (As of April 2018), the Nissan Leaf all-electric car ranked as the all-time top selling plug-in electric vehicle in the country, with over 100,000 units sold since December 2010. Ranking second is the Mitsubishi Outlander P-HEV with 34,830 units delivered through August 2016, followed by the Toyota Prius PHV with 22,100 units sold through April 2016. (As of December 2012), Japan was the country with the highest ratio of quick charging points to electric vehicles (EVSE/EV), with a ratio of 0.030 (As of December 2012). The country's charging infrastructure included 1,381 public quick-charge stations and around 300 non-domestic slow charger points. The Japanese government has set up a target to deploy 2 million slow chargers and 5,000 fast charging points by 2020.
  • 1.6K
  • 04 Oct 2022
Topic Review
Carbonation and Its Mechanisms in Reinforced Concrete Structures
Reinforced concrete (RC) has been commonly used as a construction material for decades due to its high compressive strength and moderate tensile strength. However, these two properties of RC are frequently hampered by degradation. The main degradation processes in RC structures are carbonation and the corrosion of rebars. The scientific community is divided regarding the process by which carbonation causes structural damage. Some researchers suggest that carbonation weakens a structure and makes it prone to rebar corrosion, while others suggest that carbonation does not damage structures enough to cause rebar corrosion.
  • 1.6K
  • 11 May 2022
Topic Review
3D Geological Property Modeling Methods
Three-dimensional (3D) geological property modeling is used to quantitatively characterize various geological attributes in 3D space based on geostatistics with the help of computer visualization technology, and the results are often stored in grid data. The 3D geological property modeling includes two main components, grid model generation and property interpolation.
  • 1.6K
  • 15 Jun 2022
Topic Review
Electricity Tariffs and Solutions for Optimal Energy Management
Today, electricity tariffs play an essential role in the electricity retail market as they are the key factor for the decision-making of end-users. Additionally, tariffs are necessary for increasing competition in the electricity market. They have a great impact on load energy management. Moreover, tariffs are not taken as a fixed approach to expense calculations only but are influenced by many other factors, such as electricity generation, transmission, distribution costs, and governmental taxation. Thus, electricity pricing differs significantly between countries or between regions within a country. Improper tariff calculation methodologies in some areas have led to high-power losses, unnecessary investments, increased operational expenses, and environmental pollution due to the non-use of available sustainable energy resources.
  • 1.6K
  • 25 Nov 2022
Topic Review
Biodiesel Production
Biodiesel produced through catalytic transesterification of triglycerides from edible and non-edible oils and alcohol is considered a clean and renewable alternative to traditional petro-diesel. Homogeneous alkaline catalysts have been widely used in this reaction due to their high activity. Optimization studies have been carried out to improve the biodiesel yields by modulation of the reaction conditions such as temperature, alcohol to oil ratio, catalysts concentration, time, and agitation speed. Several designs of experiments can be used to model to achieve this. 
  • 1.6K
  • 25 Feb 2021
Topic Review
Energy Management System in Microgrids
This entry gives a brief introduction to microgrids, their operations, and further, a review of different energy management approaches. In a microgrid control strategy, an energy management system (EMS) is the key component to maintain the balance between energy resources (CG, DG, ESS, and EVs) and loads available while contributing the profit to utility. This article classifies the methodologies used for EMS based on the structure, control, and technique used.
  • 1.6K
  • 22 Sep 2021
Topic Review
Shuttle–Mir Program
The Shuttle–Mir Program was a collaborative space program between Russia and the United States, which involved American Space Shuttles visiting the Russian space station Mir, Russian cosmonauts flying on the shuttle, and an American astronaut flying aboard a Soyuz spacecraft to engage in long-duration expeditions aboard Mir. The project, sometimes called "Phase One", was intended to allow the United States to learn from Russian experience with long-duration spaceflight and to foster a spirit of cooperation between the two nations and their space agencies, the US National Aeronautics and Space Administration (NASA) and the Russian Federal Space Agency (Roskosmos). The project helped to prepare the way for further cooperative space ventures; specifically, "Phase Two" of the joint project, the construction of the International Space Station (ISS). The program was announced in 1993, the first mission started in 1994 and the project continued until its scheduled completion in 1998. Eleven Space Shuttle missions, a joint Soyuz flight and almost 1000 cumulative days in space for American astronauts occurred over the course of seven long-duration expeditions. During the four-year program, many firsts in spaceflight were achieved by the two nations, including the first American astronaut to launch aboard a Soyuz spacecraft, the largest spacecraft ever to have been assembled at that time in history, and the first American spacewalk using a Russian Orlan spacesuit. The program was marred by various concerns, notably the safety of Mir following a fire and a collision, financial issues with the cash-strapped Russian Space Program and worries from astronauts about the attitudes of the program administrators. Nevertheless, a large amount of science, expertise in space station construction and knowledge in working in a cooperative space venture was gained from the combined operations, allowing the construction of the ISS to proceed much more smoothly than would have otherwise been the case.
  • 1.6K
  • 19 Oct 2022
Topic Review
Safe Mode (Spacecraft)
Safe mode is an operating mode of a modern unmanned spacecraft during which all non-essential systems are shut down and only essential functions such as thermal management, radio reception and attitude control are active. Safe mode is entered automatically upon the detection of a predefined operating condition or event that may indicate loss of control or damage to the spacecraft. Usually the trigger event is a system failure or detection of operating conditions considered dangerously out of the normal range. Cosmic rays penetrating spacecraft electrical systems can create false signals or commands and thus cause a trigger event. The central processor electronics are especially prone to such events. Another trigger is the lack of a received command within a given time window. Lack of received commands can be caused by hardware failures or mis-programming of the spacecraft, as in the case of the Viking 1 lander. The process of entering safe mode, sometimes referred to as safing, involves a number of immediate physical actions taken to prevent damage or complete loss. Power is removed from non-essential subsystems. Regaining attitude control, if lost, is the highest priority because it is necessary to maintain thermal balance and proper illumination of the solar panels. A tumbling or cartwheeling spacecraft can quickly roast, freeze or exhaust its battery power and be lost forever.
  • 1.6K
  • 02 Nov 2022
  • Page
  • of
  • 649
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
ScholarVision Creations
Feedback