Summary

HandWiki is the world's largest wiki-style encyclopedia dedicated to science, technology and computing. It allows you to create and edit articles as long as you have external citations and login account. In addition, this is a content management environment that can be used for collaborative editing of original scholarly content, such as books, manuals, monographs and tutorials.

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Nationale Plattform Elektromobilität
The German National Platform for Electric Mobility ("Nationale Plattform Elektromobilität") is an advisory council of the German Federal Government for electric vehicle introduction. It consists of the top representatives of industry (10 Members), politics (6), science (3), associations (3) and unions (1). It was officially established on 3 May 2010 during a meeting with German chancellor Angela Merkel. Its task is to push on the National Development Plan for Electric Mobility ("Nationaler Entwicklungsplan Elektromobilität"). The goal for 2020 of the NPE is to develop Germany to the leading supplier and lead market for electric mobility and to gain an employment effect of 30,000 additional jobs.
  • 947
  • 26 Oct 2022
Topic Review
Outer Space
Outer space, or simply space, is the expanse that exists beyond the Earth and between celestial bodies. Outer space is not completely empty—it is a hard vacuum containing a low density of particles, predominantly a plasma of hydrogen and helium, as well as electromagnetic radiation, magnetic fields, neutrinos, dust, and cosmic rays. The baseline temperature of outer space, as set by the background radiation from the Big Bang, is 2.7 kelvins (−270.45 °C; −454.81 °F). The plasma between galaxies accounts for about half of the baryonic (ordinary) matter in the universe; it has a number density of less than one hydrogen atom per cubic metre and a temperature of millions of kelvins. Local concentrations of matter have condensed into stars and galaxies. Studies indicate that 90% of the mass in most galaxies is in an unknown form, called dark matter, which interacts with other matter through gravitational but not electromagnetic forces. Observations suggest that the majority of the mass-energy in the observable universe is dark energy, a type of vacuum energy that is poorly understood. Intergalactic space takes up most of the volume of the universe, but even galaxies and star systems consist almost entirely of empty space. Outer space does not begin at a definite altitude above the Earth's surface. However, the Kármán line, an altitude of 100 km (62 mi) above sea level, is conventionally used as the start of outer space in space treaties and for aerospace records keeping. The framework for international space law was established by the Outer Space Treaty, which entered into force on 10 October 1967. This treaty precludes any claims of national sovereignty and permits all states to freely explore outer space. Despite the drafting of UN resolutions for the peaceful uses of outer space, anti-satellite weapons have been tested in Earth orbit. Humans began the physical exploration of space during the 20th century with the advent of high-altitude balloon flights. This was followed by manned rocket flights and, then, manned Earth orbit, first achieved by Yuri Gagarin of the Soviet Union in 1961. Due to the high cost of getting into space, manned spaceflight has been limited to low Earth orbit and the Moon. On the other hand, unmanned spacecraft have reached all of the known planets in the Solar System. Outer space represents a challenging environment for human exploration because of the hazards of vacuum and radiation. Microgravity also has a negative effect on human physiology that causes both muscle atrophy and bone loss. In addition to these health and environmental issues, the economic cost of putting objects, including humans, into space is very high.
  • 14.5K
  • 26 Oct 2022
Topic Review
WebP
WebP is an image file format developed by Google intended as a replacement for JPEG, PNG, and GIF file formats. It supports both lossy and lossless compression, as well as animation and alpha transparency. Google announced the WebP format in September 2010, and released the first stable version of its supporting library in April 2018.
  • 4.5K
  • 26 Oct 2022
Topic Review
Commercial Crew Development
Commercial Crew Development (CCDev) is a human spaceflight development program that is funded by the U.S. government and administered by NASA. CCDev will result in US and international astronauts flying to the International Space Station (ISS) on privately operated crew vehicles. Operational contracts to fly astronauts were awarded in September 2014 to SpaceX and Boeing. An uncrewed test flight was performed by each company in 2019. Space-X's Crew Dragon Demo-1 flight of Dragon 2 arrived at the International Space Station in March 2019 and returned via splashdown in the Atlantic Ocean. Due to a Mission Elapsed Time anomaly, the Boeing Orbital Flight Test of the CST-100 spacecraft failed to reach the station in December 2019, but completed some test objectives and performed a safe airbag landing in the New Mexico desert two days after launch. Pending completion of the demonstration flights, each company is contracted to supply six flights to ISS between 2019 and 2024. The first group of astronauts was announced on 3 August 2018.
  • 2.0K
  • 26 Oct 2022
Topic Review
Fleischmann–Pons Experiment
The Fleischmann–Pons experiment was an investigation conducted in the 1980s by Martin Fleischmann of the University of Southampton and Stanley Pons of the University of Utah into whether electrolysis of heavy water on the surface of a palladium (Pd) electrode produces physical effects that defy chemical explanation. Of particular interest was evidence of "excess" (i.e. non-chemical) heat extracted from the deuterium fraction of common surface water which, if true, could have delivered the largest economic shock to the global energy industry since the Pennsylvania oil rush. On March 23, 1989, Fleischmann (then one of the world's leading electrochemists) and Pons reported their work via a press release from the University of Utah (who asserted ownership of the technology) claiming that the table-top apparatus had produced anomalous heat (understood as "excess" heat) of a magnitude they asserted would defy explanation except in terms of nuclear processes, which later came to be referred to as "cold fusion". In addition to the results from calorimetry, they further reported measuring small amounts of nuclear reaction byproducts, including neutrons and tritium. The reported results received wide media attention, and raised hopes of a cheap and abundant source of energy. Many scientists tried to replicate the experiment with the few details available. Hopes faded due to the large number of negative replications, the withdrawal of many reported positive replications, the discovery of flaws and sources of experimental error in the original experiment, and finally the discovery that Fleischmann and Pons had not actually detected nuclear reaction byproducts. By late 1989, most scientists considered cold fusion claims dead.
  • 8.3K
  • 26 Oct 2022
Topic Review
Comparison of JavaScript Frameworks
There are many JavaScript frameworks available. The intention of this comparison is to show some examples of notable JavaScript frameworks.
  • 2.1K
  • 26 Oct 2022
Topic Review
HFE Hereditary Haemochromatosis
Hereditary haemochromatosis (or hemochromatosis) is a genetic disorder characterized by excessive intestinal absorption of dietary iron, resulting in a pathological increase in total body iron stores. Humans, like most animals, have no means to excrete excess iron. Excess iron accumulates in tissues and organs, disrupting their normal function. The most susceptible organs include the liver, adrenal glands, heart, skin, gonads, joints, and the pancreas; patients can present with cirrhosis, polyarthropathy, adrenal insufficiency, heart failure, or diabetes. The hereditary form of the disease is most common among those of Northern European ancestry, in particular those of Celtic descent. The disease is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition.
  • 1.5K
  • 26 Oct 2022
Topic Review
Personalized Marketing
Personalized marketing, or one-to-one marketing, individual marketing is a marketing strategy by which companies leverage data analysis and digital technology to deliver individualized messages and product offerings to current or prospective customers. Advancements in data collection methods, analytics, digital electronics, and digital economics, have enabled marketers to deploy more effective real-time and prolonged customer experience personalization tactics. Beginning in the early 1990s, web developers began tracking HTML calls that their websites were receiving from online visitors. This led to the 1993 founding of Webtrends, which is widely considered the first commercial web analytics solution. In 2012, the Web Analytics Association (WAA) officially changed its name to the Digital Analytics Association (DAA) in order to accommodate new and developing data streams that exist in addition to the web.
  • 1.2K
  • 26 Oct 2022
Topic Review
Withholding Tax
A withholding tax, or a retention tax, is an income tax to be paid to the government by the payer of the income rather than by the recipient of the income. The tax is thus withheld or deducted from the income due to the recipient. In most jurisdictions, withholding tax applies to employment income. Many jurisdictions also require withholding tax on payments of interest or dividends. In most jurisdictions, there are additional withholding tax obligations if the recipient of the income is resident in a different jurisdiction, and in those circumstances withholding tax sometimes applies to royalties, rent or even the sale of real estate. Governments use withholding tax as a means to combat tax evasion, and sometimes impose additional withholding tax requirements if the recipient has been delinquent in filing tax returns, or in industries where tax evasion is perceived to be common. Typically the withholding tax is treated as a payment on account of the recipient's final tax liability, when the withholding is made in advance. It may be refunded if it is determined, when a tax return is filed, that the recipient's tax liability to the government which received the withholding tax is less than the tax withheld, or additional tax may be due if it is determined that the recipient's tax liability is more than the withholding tax. In some cases the withholding tax is treated as discharging the recipient's tax liability, and no tax return or additional tax is required. Such withholding is known as final withholding. The amount of withholding tax on income payments other than employment income is usually a fixed percentage. In the case of employment income the amount of withholding tax is often based on an estimate of the employee's final tax liability, determined either by the employee or by the government.
  • 867
  • 26 Oct 2022
Topic Review
Analogical Models
Analogical models are a method of representing a phenomenon of the world, often called the "target system" by another, more understandable or analysable system. They are also called dynamical analogies. Two open systems have analog representations (see illustration) if they are black box isomorphic systems.
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  • 26 Oct 2022
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