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Topic Review
Silicon Carbide Power MOSFET
Owing to the superior properties of silicon carbide (SiC), such as higher breakdown voltage, higher thermal conductivity, higher operating frequency, higher operating temperature, and higher saturation drift velocity, SiC has attracted much attention from researchers and the industry for decades. With the advances in material science and processing technology, many power applications such as new smart energy vehicles, power converters, inverters, and power supplies are being realized using SiC power devices. In particular, SiC MOSFETs are generally chosen to be used as a power device due to their ability to achieve lower on-resistance, reduced switching losses, and high switching speeds than the silicon counterpart and have been commercialized extensively in recent years. 
  • 5.9K
  • 21 Mar 2022
Topic Review
Timeline of Epochs in Cosmology
The timeline of cosmological epochs outlines the formation and subsequent evolution of the Universe from the Big Bang (13.799 ± 0.021 billion years ago) to the present day. An epoch is a moment in time from which nature or situations change to such a degree that it marks the beginning of a new era or age. Times on this list are measured from the moment of the Big Bang.
  • 5.8K
  • 21 Nov 2022
Topic Review
Family Register
A family register (also known in several variations, such as household register and family album, and, when discussing non-anglophone countries, the native-language names of the registers such as koseki in Japan ,Familienbuch in Germany ,and hukou in China ) is a civil registry used in many countries to track information of a genealogical or family-centric legal interest. Often, official recognition of certain events or status may only be granted when such event or status is registered in the family registry—for example, in Japan, a marriage is legally effective when and only when such filing is recorded into the household register (known as a koseki). In other cases, the family register serves as a centralized repository for family legal events, such as births, deaths, marriages, and expatriations, as with the familienbuch in use in Germany and the livret de famille (fr) in France, although it is not the sole source of official recognition for such events. Use of government-sanctioned or administered family registers, while common in many European nations and in countries which use continental-style civil law (where the family or household is legally viewed as the fundamental unit of a nation), is nonetheless rare in English-speaking countries (for example, the closest equivalent in the United Kingdom is the electoral roll, which is also organised by household, but it is limited in the amount of information recorded). Although the United States for example assigns most citizens and residents a social security number intended to be unique to the recipient and information regarding birth, death and work history (in the form of contributions to the social security system) is collected, the U.S. social security system has long been intentionally restricted in the scope of information collected and maintained regarding individuals where not directly related to social security benefits—as such, no information is centrally collected regarding marriage, citizenship status, parentage, or the like, in contrast to the German and Japanese family register systems. Establishment of a more comprehensive personal information repository (along the lines of the Japanese or former German systems) has been criticized by civil liberties advocates as subject to governmental or criminal abuse, while proponents cite the benefits of simplified access to vital information. In South Korea, use of the hojeok (similar to the Japanese household registry, written using identical Chinese characters) was repealed in 2005, in favor of a personal registry system. The systems of household registers in China, Korea and Japan date back to the Tang Dynasty or Heian Period or earlier, both since the seventh century.
  • 5.8K
  • 19 Oct 2022
Topic Review
Multilevel DC-AC Inverters (MLIs) Topologies
Achieving a soft-switching operation is a challenging task in the development of multilevel inverters for EV motor drives. Nevertheless, multilevel inverters can present several exclusive advantages that are mainly beneficial to EVs. To be exact, they can produce nearby-sinusoidal voltage waveforms with only fundamental frequency, producing smaller harmonic contents in the output current and voltage, reduced power losses, produce almost no EMI, are appropriate for high rating motor drives, and adequate for BEVs where floating DC power sources are logically obtainable. One can overcome the difficulties of the traditional two-level inverter (TLIs). Thus, the expansion of multilevel inverters for EVs can be rapidly accelerated. Multilevel AC output waveforms can be produced by MLI circuit arrangements. Multilevel DC-AC inverters topologies can be classified as classical and advanced inverters.
  • 5.8K
  • 28 Feb 2022
Topic Review
Theory of Addiction
Drug addiction is characterized by a loss of control over drug-seeking and -consumption, despite the profound negative consequences this has on the individual’s life [1]. While the acute effects of a substance depend on its psychoactive properties, the progression of addiction converges into a series of problems that are common and severely impact all spheres of the individual’s life, compromising interpersonal, economic, and health status. Thus, in chronic drug users it is common to present several physical problems including brain damage and atrophy, circulatory system issues, premature aging, among others. From a socio-economic perspective, common problems include homelessness, criminal behavior, unemployment, social isolation, and dependence.
  • 5.8K
  • 01 Feb 2024
Biography
James Harris Simons
James Harris "Jim" Simons (/ˈsaɪmənz/; born April 25, 1938) is an American mathematician, billionaire hedge fund manager, and philanthropist. He is known as a quantitative investor and in 1982 founded Renaissance Technologies, a private hedge fund based in New York City . Although Simons retired from the fund in 2009, he remains its non-executive chairman and adviser.[1] He is also known for
  • 5.8K
  • 15 Nov 2022
Topic Review
List of Doom Source Ports
This article is a list of unofficial source ports of the Doom engine, which was originally used in the video game Doom. Most often, the source ports presented here are modifications made by the Doom community, as opposed to the official Doom versions produced by id Software or affiliated companies. The Doom engine's source code was released to the public on December 23, 1997. Although Doom was originally created for MS-DOS, the original source release was for the subsequent Linux version, due to the use of a proprietary sound library in the DOS version. The original purpose of source ports was cross-platform compatibility, but shortly after the release of the Doom source code, programmers were correcting old, unaddressed Doom bugs and deficiencies in their own source ports, and later on introducing their own modifications to enhance game features and alter gameplay. The source code was originally released under a proprietary license that prohibited commercial use and did not require programmers to provide the source code for the modifications they released in executable form, but it was later re-released on October 3, 1999 under the GNU General Public License after requests from the community.
  • 5.8K
  • 06 Feb 2023
Topic Review
Medical Waste Classification and Management Processes
The term “medical waste”, mainly refers to the waste and by-products generated from hospitals and healthcare facilities, which are being produced in huge amounts. To be addressed properly, they need to be segregated and treated according to their properties, level of contamination, and danger to living organisms and the environment.
  • 5.8K
  • 06 Dec 2022
Topic Review
Wind Turbines Vibration Control
The larger wind turbines are facing higher loads, and the imperatives of mass reduction make them more flexible. Size increase of wind turbines results in higher structural vibrations that reduce the lifetime of the components (blades, main shaft, bearings, generator, gearbox, etc.) and might lead to failure or destruction. Different systems to control the vibration of wind turbines are available, acting either on the tower or directly on the blade.
  • 5.8K
  • 06 Jun 2021
Topic Review
Introduction to Nanofluids
Due to the combination of thermal engineering and the rapid rise of nanotechnology research over the past two decades, novel heat transfer fluids known as “nanofluids” have emerged. A “nanofluid” is a heat transfer fluid that has 1–100 nm-sized “nanoparticles”, which are suspended nanoparticles, scattered throughout the base fluid. To increase the stability of the working fluid, it is crucial to make sure the nanoparticle size is smaller than 100 nm. Water, oils, organic liquids (such as tri-ethylene-glycols, ethylene and refrigerants) and bio-fluids polymeric solutions are the most often utilized base fluids. Numerous studies throughout the years have documented diverse nanofluid preparation methods with various nanoparticle types and their heat transfer capabilities, in addition to advancing the information about nanofluids.
  • 5.8K
  • 13 Dec 2022
Topic Review
Mechanical Properties of Reinforced Bioplastics
Bioplastics are a type of plastic material that is bio-based, biodegradable, or both, depending on the source from which they were created.
  • 5.8K
  • 19 Sep 2022
Topic Review
Bed Bugs
The bed bugs (Cimex lectularius and C. hemipterus) have undergone a significant resurgence worldwide since the 1990s. Herein, we discuss on the main evolutionary events, from fossil evidence, dating from 11,000 years ago, until the present that has led to the current worldwide expansion of Cimicid species. We present the hypotheses on the possible dispersion pathways of bed bugs in light of the major historical and evolutionary events. A detailed classification of the Cimicidae family and finally, an illustrative map displaying the current distribution of known Cimex species in each geographical ecozone of Asia, Europe, Africa, the Americas, and Australia are presented.
  • 5.8K
  • 05 Nov 2020
Topic Review
Tata Nano Singur Controversy
The Tata Nano Singur controversy was a controversy generated by land acquisition of a proposed Tata Motors automobile factory at Singur in Hooghly district, West Bengal, India. The factory would have been used to build the compact car Tata Nano. Tata Motors started constructing a factory to manufacture a car, Tata Nano which was estimated to cost $2,500 at Singur. The small car was scheduled to roll out of the factory by 2008. The state government of West Bengal created the controversy by citing the 1894 land acquisition act rule to conduct an eminent domain takeover of 997 acres (4.03 km2) of farmland on which Tata Motors was supposed to build its factory. The rule is meant for public improvement projects, and the West Bengal government wanted Tata to build in its state. The project was opposed by activists and opposition parties in Bengal.
  • 5.8K
  • 19 Oct 2022
Topic Review
Tumbling Mills
Tumbling mills have been widely implemented in many industrial sectors for the grinding of bulk materials. They have been used for decades in the production of fines and in the final stages of ore comminution, where optimal levels for the enrichment particles’ sizes are obtained. Even though these ubiquitous machines of relatively simple construction have been subjected to extensive studies, the industry still struggles with a very low energy efficiency of the comminution process. Moreover, obtaining an optimal size for the grinding product particles is crucial for the effectiveness of the following processes and waste production reduction. New, innovative processing methods and machines are being developed to tackle the problem; however, tumbling mills are still most commonly used in all ranges of the industry. Since heavy equipment retrofitting is the most costly approach, process optimization with dedicated models and control systems is the most preferable solution for energy consumption reduction. While the classic technological measurements in mineral processing are well adopted by the industry, nowadays research focuses on new methods of the mill’s internal dynamics analysis and control.
  • 5.8K
  • 19 Jan 2021
Topic Review
Sustainable Valorization of Sugarcane Waste from Sugarcane Processing
Sugarcane is a lignocellulosic crop and the juice extracted from its stalks provides the raw material for 86% of sugar production. Globally, sugarcane processing to obtain sugar and/or ethanol generates more than 279 million tons of solid and liquid waste annually, as well as by-products; namely, straws, bagasse, press mud, wastewater, ash from bagasse incineration, vinasse from ethanol distillation, and molasses. If not properly managed, this waste will pose risks to both environmental factors and human health. Valorization of waste has gained momentum, having an important contribution to the fulfillment of policies and objectives related to sustainable development and circular bioeconomy. Various technologies are well-established and implemented for the valorization of waste and by-products from sugarcane processing, while other innovative technologies are still in the research and development stage, with encouraging prospects.
  • 5.8K
  • 19 Sep 2022
Topic Review
Environmental Awareness and Individual’s Altruism
Environmental awareness is the level of how much people are interested in or care about environmental issues. Environmental awareness can be either local or global one depending on the type of environmental problem. Studies have argued that this awareness tends to be related to an individual’s altruism, which is one’s action that benefits others without expecting some kind of external reward. The connection between environmental awareness and altruism is getting attention from scholars since both concepts are prosocial ones but it is uncertain if people who are highly aware of environmental issues may not be always acting altruistically. However, it is likely that altruistic people are more likely to have high environmental awareness.
  • 5.8K
  • 28 Oct 2020
Topic Review
Limit Superior and Limit Inferior
In mathematics, the limit inferior and limit superior of a sequence can be thought of as limiting (i.e., eventual and extreme) bounds on the sequence. They can be thought of in a similar fashion for a function (see limit of a function). For a set, they are the infimum and supremum of the set's limit points, respectively. In general, when there are multiple objects around which a sequence, function, or set accumulates, the inferior and superior limits extract the smallest and largest of them; the type of object and the measure of size is context-dependent, but the notion of extreme limits is invariant. Limit inferior is also called infimum limit, limit infimum, liminf, inferior limit, lower limit, or inner limit; limit superior is also known as supremum limit, limit supremum, limsup, superior limit, upper limit, or outer limit. The limit inferior of a sequence [math]\displaystyle{ x_n }[/math] is denoted by The limit superior of a sequence [math]\displaystyle{ x_n }[/math] is denoted by
  • 5.8K
  • 30 Nov 2022
Topic Review
Scottish Highlands
The Highlands (Scots: the Hielands; Scottish Gaelic: a’ Ghàidhealtachd [ə ˈɣɛːəl̪ˠt̪ʰəxk], 'the place of the Gaels') is a historical region of Scotland. Culturally, the Highlands and the Lowlands diverged from the Late Middle Ages into the modern period, when Lowland Scots replaced Scottish Gaelic throughout most of the Lowlands. The term is also used for the area north and west of the Highland Boundary Fault, although the exact boundaries are not clearly defined, particularly to the east. The Great Glen divides the Grampian Mountains to the southeast from the Northwest Highlands. The Scottish Gaelic name of A' Ghàidhealtachd literally means "the place of the Gaels" and traditionally, from a Gaelic-speaking point of view, includes both the Western Isles and the Highlands.The area is very sparsely populated, with many mountain ranges dominating the region, and includes the highest mountain in the British Isles, Ben Nevis. During the 18th and early 19th centuries the population of the Highlands rose to around 300,000, but from c. 1841 and for the next 160 years, the natural increase in population was exceeded by emigration (mostly to Canada, the United States, Australia and New Zealand, and migration to the industrial cities of Scotland and England.):xxiii, 414 and passim The area is now one of the most sparsely populated in Europe. At 9.1/km2 (24/sq mi) in 2012, the population density in the Highlands and Islands is less than one seventh of Scotland's as a whole, comparable with that of Bolivia, Chad and Russia . The Highland Council is the administrative body for much of the Highlands, with its administrative centre at Inverness. However, the Highlands also includes parts of the council areas of Aberdeenshire, Angus, Argyll and Bute, Moray, North Ayrshire, Perth and Kinross, Stirling and West Dunbartonshire. The Scottish Highlands is the only area in the British Isles to have the taiga biome as it features concentrated populations of Scots pine forest: see Caledonian Forest. It is the most mountainous part of the United Kingdom .
  • 5.8K
  • 30 Nov 2022
Topic Review
Unbibium
Unbibium /uːnˈbɪbiəm/, also known as eka-thorium or simply element 122, is the currently hypothetical chemical element in the periodic table with the placeholder symbol of Ubb and atomic number 122. Unbibium and Ubb are the temporary systematic IUPAC name and symbol respectively, until a permanent name is decided upon. In the periodic table of the elements, it is expected to follow unbiunium as the second element of the superactinides, or the g-block and the fourth element of the 8th period. It has attracted recent attention, for similarly to unbiunium, it is expected to fall within the range of the island of stability. Despite many attempts, unbibium has not yet been synthesized, and therefore no natural isotopes have been found to exist. It is currently predicted that it has a g-orbital, the second element of which to have such besides unbiunium, which also has yet to be synthesized. It will most likely require nuclear fission to be produced artificially. In 2008, it was claimed to have been discovered in natural thorium samples but that claim has now been dismissed by recent repetitions of the experiment using more accurate techniques.
  • 5.8K
  • 29 Nov 2022
Topic Review
Stock Market Prediction
Stock Market Prediction (SMP) is an example of time-series forecasting that promptly examines previous data and estimates future data values. Financial market prediction has been a matter of worry for analysts in different disciplines, including economics, mathematics, material science, and computer science. Driving profits from the trading of stocks is an important factor for the prediction of the stock market.
  • 5.8K
  • 09 Dec 2021
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