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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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Long Shot
In photography, filmmaking and video production, a long shot (sometimes referred to as a full shot or wide shot) typically shows the entire object or human figure and is usually intended to place it in some relation to its surroundings. These are typically shot now using wide-angle lenses (an approximately 25 mm lens in 35 mm photography and 10 mm lens in 16 mm photography). However, due to sheer distance, establishing shots and extremely wide shots can use almost any camera type.
  • 2.6K
  • 14 Oct 2022
Topic Review
Steady State Model
In cosmology, the steady state model is an alternative to the Big Bang theory of the evolution of our universe. In the steady state model, the density of matter in the expanding universe remains unchanged due to a continuous creation of matter, thus adhering to the perfect cosmological principle, a principle that asserts that the observable universe is basically the same at any time as well as at any place. While the steady state model enjoyed some popularity in the mid-20th century (though less popularity than the Big Bang theory), it is now rejected by the vast majority of cosmologists, astrophysicists and astronomers, as the observational evidence points to a hot Big Bang cosmology with a finite age of the universe, which the steady state model does not predict.
  • 3.8K
  • 14 Oct 2022
Topic Review
Turing Reduction
In computability theory, a Turing reduction from a problem A to a problem B, is a reduction which solves A, assuming the solution to B is already known (Rogers 1967, Soare 1987). It can be understood as an algorithm that could be used to solve A if it had available to it a subroutine for solving B. More formally, a Turing reduction is a function computable by an oracle machine with an oracle for B. Turing reductions can be applied to both decision problems and function problems. If a Turing reduction of A to B exists then every algorithm for B can be used to produce an algorithm for A, by inserting the algorithm for B at each place where the oracle machine computing A queries the oracle for B. However, because the oracle machine may query the oracle a large number of times, the resulting algorithm may require more time asymptotically than either the algorithm for B or the oracle machine computing A, and may require as much space as both together. The first formal definition of relative computability, then called relative reducibility, was given by Alan Turing in 1939 in terms of oracle machines. Later in 1943 and 1952 Stephen Kleene defined an equivalent concept in terms of recursive functions. In 1944 Emil Post used the term "Turing reducibility" to refer to the concept. A polynomial-time Turing reduction is known as a Cook reduction, after Stephen Cook.
  • 5.5K
  • 14 Oct 2022
Topic Review
FireEye
FireEye is a privately held cybersecurity company headquartered in Milpitas, California. It has been involved in the detection and prevention of major cyber attacks. It provides hardware, software, and services to investigate cybersecurity attacks, protect against malicious software, and analyze IT security risks. FireEye was founded in 2004. Initially, it focused on developing virtual machines that would download and test internet traffic before transferring it to a corporate or government network. The company diversified over time, in part through acquisitions. In 2014, it acquired Mandiant, which provides incident response services following the identification of a security breach. FireEye went public in 2013. USAToday says FireEye "has been called in to investigate high-profile attacks against Target, JP Morgan Chase, Sony Pictures, Anthem and others".
  • 3.9K
  • 18 Oct 2022
Topic Review
Propene
Propene, also known as propylene, is an unsaturated organic compound with the chemical formula [math]\ce{ CH3CH=CH2 }[/math]. It has one double bond, and is the second simplest member of the alkene class of hydrocarbons. It is a colorless gas with a faint petroleum-like odor.
  • 8.7K
  • 14 Oct 2022
Topic Review
Scale Relativity
Scale relativity is a geometrical and fractal space-time physical theory. Relativity theories (special relativity and general relativity) are based on the notion that position, orientation, movement and acceleration cannot be defined in an absolute way, but only relative to a system of reference. The scale relativity theory proposes to extend the concept of relativity to physical scales (time, length, energy, or momentum scales), by introducing an explicit "state of scale" in coordinate systems. This extension of the relativity principle using fractal geometries to study scale transformations was originally introduced by Laurent Nottale, based on the idea of a fractal space-time theory first introduced by Garnet Ord, and by Nottale and Jean Schneider. The construction of the theory is similar to previous relativity theories, with three different levels: Galilean, special and general. The development of a full general scale relativity is not finished yet.
  • 3.6K
  • 14 Oct 2022
Topic Review
Single-Molecule Magnetic Sequencing
Magnetic sequencing is a single-molecule sequencing method in development. A DNA hairpin, containing the sequence of interest, is bound between a magnetic bead and a glass surface. A magnetic field is applied to stretch the hairpin open into single strands, and the hairpin refolds after decreasing of the magnetic field. The hairpin length can be determined by direct imaging of the diffraction rings of the magnetic beads using a simple microscope. The DNA sequences are determined by measuring the changes in the hairpin length following successful hybridization of complementary nucleotides.
  • 1.1K
  • 18 Oct 2022
Topic Review
Behavioral Strategy
Behavioral strategy strategy refers to the application of insights from psychology and behavioral economics to the research and practice of strategic management. In one definition of the field, “Behavioral strategy merges cognitive and social psychology with strategic management theory and practice. Behavioral strategy aims to bring realistic assumptions about human cognition, emotions, and social behavior to the strategic management of organizations and, thereby, to enrich strategy theory, empirical research, and real-world practice” (Powell, Lovallo & Fox, 2011: 1371).
  • 3.2K
  • 14 Oct 2022
Topic Review
Runoff Model (Reservoir)
A runoff model is a mathematical model describing the rainfall–runoff relations of a rainfall catchment area, drainage basin or watershed. More precisely, it produces a surface runoff hydrograph in response to a rainfall event, represented by and input as a hyetograph. In other words, the model calculates the conversion of rainfall into runoff. A well known runoff model is the linear reservoir, but in practice it has limited applicability. The runoff model with a non-linear reservoir is more universally applicable, but still it holds only for catchments whose surface area is limited by the condition that the rainfall can be considered more or less uniformly distributed over the area. The maximum size of the watershed then depends on the rainfall characteristics of the region. When the study area is too large, it can be divided into sub-catchments and the various runoff hydrographs may be combined using flood routing techniques. Rainfall-runoff models need to be calibrated before they can be used.
  • 1.7K
  • 18 Oct 2022
Topic Review
Up Series
Lua error in package.lua at line 80: module 'Module:Television infoboxes disambiguation check' not found. The Up Series is a series of documentary films produced by Granada Television for ITV that have followed the lives of fourteen British children since 1964, when they were seven years old. So far the documentary has had eight episodes spanning 49 years (one episode every seven years) all of which were broadcast on ITV, apart from the 6th episode which was broadcast on BBC One. In a 2005 Channel 4 programme, the series topped the list of The 50 Greatest Documentaries. The children were selected to represent the range of socio-economic backgrounds in Britain at that time, with the explicit assumption that each child's social class predetermines their future. Every seven years, the director, Michael Apted, films material from those of the fourteen who choose to participate. The last installment, 56 Up, premiered in May 2012; Apted has stated that filming for 63 Up will occur in late 2018, for release in spring 2019. Apted has also been reported as saying: "I hope to do 84 Up when I'll be 99." The aim of the series is stated at the beginning of 7 Up as: "Why do we bring these children together? Because we want to get a glimpse of England in the year 2000. The shop steward and the executive of the year 2000 are now seven years old."
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  • 14 Oct 2022
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