Topic Review
Foursquare
Foursquare is a local search-and-discovery service mobile app which provides search results for its users. The app provides personalized recommendations of places to go to near a user's current location based on users' "previous browsing history, purchases, or check-in history". The service was created in late 2008 and launched in 2009 by Dennis Crowley and Naveen Selvadurai. Crowley had previously founded the similar project Dodgeball as his graduate thesis project in the Interactive Telecommunications Program (ITP) at New York University. Google bought Dodgeball in 2005 and shut it down in 2009, replacing it with Google Latitude. Dodgeball user interactions were based on SMS technology, rather than an application. Foursquare was the second iteration of that same idea, that people can use mobile devices to interact with their environment. Foursquare was Dodgeball reimagined to take advantage of the new smartphones, like the iPhone, which had built in GPS to better detect a user's location. Until late July 2014, Foursquare featured a social networking layer that enabled a user to share their location with friends, via the "check in" - a user would manually tell the application when they were at a particular location using a mobile website, text messaging, or a device-specific application by selecting from a list of venues the application locates nearby. In May 2014, the company launched Swarm, a companion app to Foursquare, that reimagined the social networking and location sharing aspects of the service as a separate application. On August 7, 2014 the company launched Foursquare 8.0, the completely new version of the service which finally removed the check in and location sharing entirely, to focus entirely on local search. As of December 2013, Foursquare reported 45 million registered users, though many of these will not be active users. Male and female users are equally represented and also 50 percent of users are outside the US. Support for French, Italian, German, Spanish, and Japanese was added in February 2011. Support for Indonesian, Korean, Portuguese, Russian, and Thai was added in September 2011. Support for Turkish was added in June 2012. On January 14, 2016, Co-founder Dennis Crowley stepped down from his position as CEO. He moved to an Executive Chairman position while Jeff Glueck, the company's COO, succeeded Crowley as the new CEO.
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Topic Review
Complement (Set Theory)
In set theory, the complement of a set A, often denoted by Ac (or A′), is the set of elements not in A. When all sets in the universe, i.e. all sets under consideration, are considered to be members of a given set U, the absolute complement of A is the set of elements in U that are not in A. The relative complement of A with respect to a set B, also termed the set difference of B and A, written [math]\displaystyle{ B \setminus A, }[/math] is the set of elements in B that are not in A.
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Topic Review
Comparison of Notetaking Software
The tables below compare features of notable note-taking software.
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Topic Review
Catholic Encyclopedia
File:Catholic Encyclopedia, volume 1.djvu The Catholic Encyclopedia: An International Work of Reference on the Constitution, Doctrine, Discipline, and History of the Catholic Church, also referred to as the Old Catholic Encyclopedia and the Original Catholic Encyclopedia, is an English-language encyclopedia published in the United States and designed to serve the Roman Catholic Church. The first volume appeared in March 1907 and the last three volumes appeared in 1912, followed by a master index volume in 1914 and later supplementary volumes. It was designed "to give its readers full and authoritative information on the entire cycle of Catholic interests, action and doctrine". The Catholic Encyclopedia was published by the Robert Appleton Company (RAC), a publishing company incorporated at New York in February 1905 for the express purpose of publishing the encyclopedia. The five members of the encyclopedia's Editorial Board also served as the directors of the company. In 1912 the company's name was changed to The Encyclopedia Press. Publication of the encyclopedia's volumes was the sole business conducted by the company during the project's lifetime.
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Topic Review
Two-Dimensional Space
Two-dimensional space (also known as 2D space, 2-space, or bi-dimensional space) is a geometric setting in which two values (called parameters) are required to determine the position of an element (i.e., point). The set [math]\displaystyle{ \mathbb{R}^2 }[/math] of pairs of real numbers with appropriate structure often serves as the canonical example of a two-dimensional Euclidean space. For a generalization of the concept, see dimension. Two-dimensional space can be seen as a projection of the physical universe onto a plane. Usually, it is thought of as a Euclidean space and the two dimensions are called length and width.
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Topic Review
Dr. DivX
Dr. DivX was an application created by DivX, Inc. that is capable of transcoding many video formats to DivX encoded video.
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Topic Review
Computational Biology in Drug Design
Traditional drug design requires a great amount of research time and developmental expense. Booming computational approaches, including computational biology, computer-aided drug design, and artificial intelligence, have the potential to expedite the efficiency of drug discovery by minimizing the time and financial cost. In recent years, computational approaches are being widely used to improve the efficacy and effectiveness of drug discovery and pipeline, leading to the approval of plenty of new drugs for marketing. The present review emphasizes on the applications of these indispensable computational approaches in aiding target identification, lead discovery, and lead optimization. Some challenges of using these approaches for drug design are also discussed. Moreover, researchers propose a methodology for integrating various computational techniques into new drug discovery and design.
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Topic Review
Physics-Informed Neural Networks
Physics-informed neural networks (PINNs) are a type of universal function approximators that can embed the knowledge of any physical laws that govern a given data-set in the learning process, and can be described by partial differential equations (PDEs). They overcome the low data availability of some biological and engineering systems that makes most state-of-the-art machine learning techniques lack robustness, rendering them ineffective in these scenarios. The prior knowledge of general physical laws acts in the training of neural networks (NNs) as a regularization agent that limits the space of admissible solutions, increasing the correctness of the function approximation. This way, embedding this prior information into a neural network results in enhancing the information content of the available data, facilitating the learning algorithm to capture the right solution and to generalize well even with a low amount of training examples.
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Topic Review
Rpm
RPM Package Manager (RPM) (originally Red Hat Package Manager; now a recursive acronym) is a package management system. The name RPM refers to the following: the .rpm file format, files in the .rpm file format, software packaged in such files, and the package manager program itself. RPM was intended primarily for Linux distributions; the file format is the baseline package format of the Linux Standard Base. Even though it was created for use in Red Hat Linux, RPM is now used in many Linux distributions. It has also been ported to some other operating systems, such as Novell NetWare (as of version 6.5 SP3), IBM's AIX (as of version 4), CentOS, Fedora (operating system) created jointly between Red Hat and the Fedora community, and Oracle Linux. All versions or variants of the these Linux operating systems use the RPM Package Manager. An RPM package can contain an arbitrary set of files. The larger part of RPM files encountered are “binary RPMs” (or BRPMs) containing the compiled version of some software. There are also “source RPMs” (or SRPMs) files containing the source code used to produce a package. These have an appropriate tag in the file header that distinguishes them from normal (B)RPMs, causing them to be extracted to /usr/src on installation. SRPMs customarily carry the file extension “.src.rpm” (.spm on file systems limited to 3 extension characters, e.g. old DOS FAT).
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Topic Review
Gauss's Lemma (Polynomial)
In algebra, Gauss's lemma, named after Carl Friedrich Gauss, is a statement about polynomials over the integers, or, more generally, over a unique factorization domain (that is, a ring that has a unique factorization property similar to the fundamental theorem of arithmetic). Gauss's lemma underlies all the theory of factorization and greatest common divisors of such polynomials. Gauss's lemma asserts that the product of two primitive polynomials is primitive (a polynomial with integer coefficients is primitive if it has 1 as a greatest common divisor of its coefficients). A corollary of Gauss's lemma, sometimes also called Gauss's lemma, is that a primitive polynomial is irreducible over the integers if and only if it is irreducible over the rational numbers. More generally, a primitive polynomial has the same complete factorization over the integers and over the rational numbers. In the case of coefficients in a unique factorization domain R, "rational numbers" must be replaced by "field of fractions of R". This implies that, if R is either a field, the ring of integers, or a unique factorization domain, then every polynomial ring (in one or several indeterminates) over R is a unique factorization domain. Another consequence is that factorization and greatest common divisor computation of polynomials with integers or rational coefficients may be reduced to similar computations on integers and primitive polynomials. This is systematically used (explicitly or implicitly) in all implemented algorithms (see Polynomial greatest common divisor and Factorization of polynomials). Gauss's lemma, and all its consequences that do not involve the existence of a complete factorization remain true over any GCD domain (an integral domain over which greatest common divisors exist). In particular, a polynomial ring over a GCD domain is also a GCD domain. If one calls primitive a polynomial such that the coefficients generate the unit ideal, Gauss's lemma is true over every commutative ring. However, some care must be taken, when using this definition of primitive, as, over a unique factorization domain that is not a principal ideal domain, there are polynomials that are primitive in the above sense and not primitive in this new sense.
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