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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CVF (Microsoft)
DriveSpace (initially known as DoubleSpace) is a disk compression utility supplied with MS-DOS starting from version 6.0 in 1993 and ending in 2000 with the release of Windows Me. The purpose of DriveSpace is to increase the amount of data the user could store on disks by transparently compressing and decompressing data on-the-fly. It is primarily intended for use with hard drives, but use for floppy disks is also supported. This feature was removed in Windows XP and later.
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  • 19 Oct 2022
Topic Review
Broken/Asymptotic Safety in Quantum Gravity
Asymptotic safety (sometimes also referred to as nonperturbative renormalizability) is a concept in quantum field theory which aims at finding a consistent and predictive quantum theory of the gravitational field. Its key ingredient is a nontrivial fixed point of the theory's renormalization group flow which controls the behavior of the coupling constants in the ultraviolet (UV) regime and renders physical quantities safe from divergences. Although originally proposed by Steven Weinberg to find a theory of quantum gravity, the idea of a nontrivial fixed point providing a possible UV completion can be applied also to other field theories, in particular to perturbatively nonrenormalizable ones. In this respect, it is similar to quantum triviality. The essence of asymptotic safety is the observation that nontrivial renormalization group fixed points can be used to generalize the procedure of perturbative renormalization. In an asymptotically safe theory the couplings do not need to be small or tend to zero in the high energy limit but rather tend to finite values: they approach a nontrivial UV fixed point. The running of the coupling constants, i.e. their scale dependence described by the renormalization group (RG), is thus special in its UV limit in the sense that all their dimensionless combinations remain finite. This suffices to avoid unphysical divergences, e.g. in scattering amplitudes. The requirement of a UV fixed point restricts the form of the bare action and the values of the bare coupling constants, which become predictions of the asymptotic safety program rather than inputs. As for gravity, the standard procedure of perturbative renormalization fails since Newton's constant, the relevant expansion parameter, has negative mass dimension rendering general relativity perturbatively nonrenormalizable. This has driven the search for nonperturbative frameworks describing quantum gravity, including asymptotic safety which — in contrast to other approaches—is characterized by its use of quantum field theory methods, without depending on perturbative techniques, however. At the present time, there is accumulating evidence for a fixed point suitable for asymptotic safety, while a rigorous proof of its existence is still lacking.
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  • 19 Oct 2022
Topic Review
Online Music Store
An online music store is an online business which sells audio files over the Internet, usually sound recordings of music songs or classical pieces, in which the user pays on a per-song or subscription basis. It may be differentiated from music streaming services in that the online music store sells the purchaser the actual digital music file, while streaming services offer the patron partial or full listening without the actually owning the source file. However, online music stores generally offer partial streaming previews of songs, with some songs even available for full length listening. Online music stores typically show a picture of the album art or of the performer or band for each song. Some online music stores also sell recorded speech files, such as podcasts and video files of movies.
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  • 19 Oct 2022
Topic Review
Monitoring Control and Surveillance
Monitoring, control and surveillance (MCS), in the context of fisheries, is defined by the Food and Agriculture Organization (FAO) of the United Nations as a broadening of traditional enforcing national rules over fishing, to the support of the broader problem of fisheries management. Internationally, the basis of law for fisheries management comes from the 1982 United Nations Convention on the Law of the Sea (UNCLOS). Further definition was in the Declaration of Cancun This is complemented by the work of a variety of regional organizations that cover high seas fishing areas. A key concept in international fishing laws is that of the Exclusive Economic Zone, which extends 200 miles (370 km) from the coast of nations bordering on the oceans. EEZ is not a meaningful concept in relatively small seas such as the Mediterranean and Baltic, so those areas tend to have regional agreements for MCS of international waters within those seas.
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  • 19 Oct 2022
Topic Review
Point Set Registration
In computer vision, pattern recognition, and robotics, point set registration, also known as point cloud registration or scan matching, is the process of finding a spatial transformation (e.g., scaling, rotation and translation) that aligns two point clouds. The purpose of finding such a transformation includes merging multiple data sets into a globally consistent model (or coordinate frame), and mapping a new measurement to a known data set to identify features or to estimate its pose. Raw 3D point cloud data are typically obtained from Lidars and RGB-D cameras. 3D point clouds can also be generated from computer vision algorithms such as triangulation, bundle adjustment, and more recently, monocular image depth estimation using deep learning. For 2D point set registration used in image processing and feature-based image registration, a point set may be 2D pixel coordinates obtained by feature extraction from an image, for example corner detection. Point cloud registration has extensive applications in autonomous driving, motion estimation and 3D reconstruction, object detection and pose estimation, robotic manipulation, simultaneous localization and mapping (SLAM), panorama stitching, virtual and augmented reality, and medical imaging. As a special case, registration of two point sets that only differ by a 3D rotation (i.e., there is no scaling and translation), is called the Wahba Problem and also related to the orthogonal procrustes problem.
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  • 19 Oct 2022
Topic Review
Economics of Global Warming
The economics of global warming concerns the economic aspects of global warming; this can inform policies that governments might consider in response. A number of factors make this a difficult problem from both economic and political perspectives: it is a long-term, intergenerational problem; benefits and costs are distributed unequally both within and across countries; and both scientific and public opinions need to be taken into account. One of the most important greenhouse gases is carbon dioxide (CO2). Around 20% of carbon dioxide which is emitted due to human activities can remain in the atmosphere for many thousands of years. The long time scales and uncertainty associated with global warming have led analysts to develop "scenarios" of future environmental, social and economic changes. These scenarios can help governments understand the potential consequences of their decisions. The impacts of climate change include the loss of biodiversity, sea level rise, increased frequency and severity of some extreme weather events, and acidification of the oceans. Economists have attempted to quantify these impacts in monetary terms, but these assessments can be controversial. The two main policy responses to global warming are to reduce greenhouse gas emissions (climate change mitigation) and to adapt to the impacts of global warming (e.g., by building levees in response to sea level rise). Another policy response which has recently received greater attention is geoengineering of the climate system (e.g. injecting aerosols into the atmosphere to reflect sunlight away from the Earth's surface). One of the responses to the uncertainties of global warming is to adopt a strategy of sequential decision making. This strategy recognizes that decisions on global warming need to be made with incomplete information, and that decisions in the near term will have potentially long-term impacts. Governments might choose to use risk management as part of their policy response to global warming. For instance, a risk-based approach can be applied to climate impacts which are difficult to quantify in economic terms, e.g., the impacts of global warming on indigenous peoples. Analysts have assessed global warming in relation to sustainable development. Sustainable development considers how future generations might be affected by the actions of the current generation. In some areas, policies designed to address global warming may contribute positively towards other development objectives. In other areas, the cost of global warming policies may divert resources away from other socially and environmentally beneficial investments (the opportunity costs of climate change policy).
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  • 19 Oct 2022
Topic Review
Doctor of Medicine
Doctor of Medicine (abbreviated M.D., from the Latin Medicinae Doctor) is a medical degree, the meaning of which varies between different jurisdictions. In the United States , and some other countries, the M.D. denotes a professional graduate degree. This generally arose because many in 18th-century medical professions trained in Scotland, which used the M.D. degree nomenclature. In England, however, Bachelor of Medicine, Bachelor of Surgery was used and eventually in the 19th century became the standard in Scotland too. Thus, in the United Kingdom , Ireland and other countries, the M.D. is a research doctorate, higher doctorate, honorary doctorate or applied clinical degree restricted to those who already hold a professional degree (Bachelor's/Master's/Doctoral) in medicine; in those countries, the equivalent professional to the North American and some others use of M.D. is still typically titled Bachelor of Medicine, Bachelor of Surgery (M.B.B.S.).
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  • 19 Oct 2022
Topic Review
Euler Line
In geometry, the Euler line, named after Leonhard Euler (/ˈɔɪlər/), is a line determined from any triangle that is not equilateral. It is a central line of the triangle, and it passes through several important points determined from the triangle, including the orthocenter, the circumcenter, the centroid, the Exeter point and the center of the nine-point circle of the triangle. The concept of a triangle's Euler line extends to the Euler line of other shapes, such as the quadrilateral and the tetrahedron.
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  • 19 Oct 2022
Topic Review
Ohaguro
Ohaguro (お歯黒) is a custom of dyeing one's teeth black. It was most popular in Japan until the Meiji era. Tooth painting is also known and practiced in the southeastern parts of China , Pacific Islands and Southeast Asia. Dyeing is mainly done by married women, though occasionally men do it as well. It was also beneficial, as it prevented tooth decay, in a similar fashion to modern dental sealants.
  • 10.1K
  • 19 Oct 2022
Topic Review
National Herald Scam
The National Herald scam is an ongoing case in a Delhi court filed by Indian economist and politician Subramanian Swamy against politicians Sonia Gandhi and Rahul Gandhi, their companies and associated persons. As per the complaint filed in the court of the Metropolitan Magistrate, Associated Journals Limited (AJL) took an interest-free loan of ₹90.25 crore (US$13 million) from Indian National Congress. It is alleged that the loan was not repaid. A closely held company, Young Indian, was incorporated in November 2010 with a capital of ₹50 lakh (US$70,000) and it acquired almost all the shareholding of AJL and all its properties (alleged to be worth ₹5,000 crore (US$700 million)). Swamy alleged criminal misappropriation by both Sonia Gandhi and Rahul Gandhi. The courts have determined that a prima face case has been established in the matter.
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  • 19 Oct 2022
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