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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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July 2009 Cyberattacks
The July 2009 cyberattacks were a series of coordinated cyberattacks against major government, news media, and financial websites in South Korea and the United States . The attacks involved the activation of a botnet—a large number of hijacked computers—that maliciously accessed targeted websites with the intention of causing their servers to overload due to the influx of traffic, known as a DDoS attack. Most of the hijacked computers were located in South Korea. The estimated number of the hijacked computers varies widely; around 20,000 according to the South Korean National Intelligence Service, around 50,000 according to Symantec's Security Technology Response group, and more than 166,000 according to a Vietnamese computer security researcher who analyzed the log files of the two servers the attackers controlled. An investigation revealed that at least 39 websites were targets in the attacks based on files stored on compromised systems. The targeting and timing of the attacks—which started the same day as a North Korean short-range ballistic missile test—have led to suggestions that they may be from North Korea, although these suggestions have not been substantiated. Researchers would later find links between these cyberattacks, the DarkSeoul attacks in 2013, and other attacks attributed to the Lazarus Group. This attack is considered by some to be the beginning of a series of DDoS attacks carried about by Lazarus dubbed "Operation Troy."
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  • 11 Nov 2022
Topic Review
Rerikhism
Rerikhism or Roerichism (Russian: Рерихи́зм, Рерихиа́нство, Ре́риховское движе́ние) is a spiritual and cultural movement centered on the teachings transmitted by Helena and Nicholas Roerich. It draws ideas from Theosophy, Eastern and Western religions, and Vedic and Buddhist traditions, molding them into the Russian culture and Russian cosmism.
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  • 11 Nov 2022
Biography
Syed Ahmad Khan
Syed Ahmad Taqvi bin Syed Muhammad Muttaqi[1] KCSI (Urdu: سید احمد خان‎; 17 October 1817 – 27 March 1898), commonly known as Sir Syed Ahmad Khan (also Sayyid Ahmad Khan), was an Indian Islamic pragmatist,[2] Islamic reformer,[3][4] philosopher, and educationist[5] in nineteenth-century British India.[6][7] Though initially espousing Hindu-Muslim unity, he became the pioneer of Mu
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  • 15 Nov 2022
Topic Review
LGBT Social Movements
Lesbian, gay, bisexual, and transgender (LGBT) social movements are social movements that advocate for LGBT people in society. Social movements may focus on equal rights, such as the 2000s movement for same-sex marriage, or they may focus on liberation, as in the gay liberation movement of the 1960s and 1970s. Earlier movements focused on self-help and self-acceptance, such as the homophile movement of the 1950s. Although there is not a primary or an overarching central organization that represents all LGBT people and their interests, numerous LGBT rights organizations are active worldwide. The earliest organizations to support LGBT rights were formed in the early 20th century. A commonly stated goal among these movements is social equality for LGBT people, but there is still denial of full LGBT rights. Some have also focused on building LGBT communities or worked towards liberation for the broader society from biphobia, homophobia, and transphobia. There is a struggle for LGBT rights today. LGBT movements organized today are made up of a wide range of political activism and cultural activity, including lobbying, street marches, social groups, media, art, and research.
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  • 11 Nov 2022
Biography
C. D. Broad
Charlie Dunbar Broad FBA (30 December 1887 – 11 March 1971), usually cited as C. D. Broad, was an English epistemologist, historian of philosophy, philosopher of science, moral philosopher, and writer on the philosophical aspects of psychical research. He was known for his thorough and dispassionate examinations of arguments in such works as Scientific Thought (1923), The Mind and Its Place i
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  • 15 Nov 2022
Biography
Nick Katz
Nicholas Michael Katz (born December 7, 1943) is an United States mathematician, working in the fields of algebraic geometry, particularly on p-adic methods, monodromy and moduli problems, and number theory. He is currently a professor in the Mathematics Department at Princeton University in Princeton, New Jersey and an editor of the journal Annals of Mathematics.[1] Katz graduated from Johns
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  • 11 Nov 2022
Topic Review
Bi-Directional Text
Bi-directional text is text containing text in both text directionalities, both right-to-left (RTL or dextrosinistral) and left-to-right (LTR or sinistrodextral). It generally involves text containing different types of alphabets, but may also refer to boustrophedon, which is changing text directionality in each row. Some writing systems of the world, including the Arabic and Hebrew scripts or derived systems such as the Persian, Urdu, and Yiddish scripts, are written in a form known as right-to-left (RTL), in which writing begins at the right-hand side of a page and concludes at the left-hand side. This is different from the left-to-right (LTR) direction used by the dominant Latin script. When LTR text is mixed with RTL in the same paragraph, each type of text is written in its own direction, which is known as bi-directional text. This can get rather complex when multiple levels of quotation are used. Many computer programs fail to display bi-directional text correctly. For example, the Hebrew name Sarah (שרה) is spelled: sin (ש) (which appears rightmost), then resh (ר), and finally heh (ה) (which should appear leftmost). Note: Some web browsers may display the Hebrew text in this article in the opposite direction.
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  • 11 Nov 2022
Topic Review
KIC 8462852
KIC 8462852 (also Tabby's Star or Boyajian's Star) is an F-type main-sequence star located in the constellation Cygnus approximately 1,470 light-years (450 pc) from Earth. Unusual light fluctuations of the star, including up to a 22% dimming in brightness, were discovered by citizen scientists as part of the Planet Hunters project. In September 2015, astronomers and citizen scientists associated with the project posted a preprint of an article describing the data and possible interpretations. The discovery was made from data collected by the Kepler space telescope, which observes changes in the brightness of distant stars to detect exoplanets. Several hypotheses have been proposed to explain the star's large irregular changes in brightness as measured by its light curve, but none to date fully explain all aspects of the curve. One explanation is that an "uneven ring of dust" orbits KIC 8462852. In another explanation, the star's luminosity is modulated by changes in the efficiency of heat transport to its photosphere, so no external obscuration is required. A third hypothesis, based on a lack of observed infrared light, posits a swarm of cold, dusty comet fragments in a highly eccentric orbit, however, the notion that disturbed comets from such a cloud could exist in high enough numbers to obscure 22% of the star's observed luminosity has been doubted. Another hypothesis is that a large number of small masses in "tight formation" are orbiting the star. Furthermore, spectroscopic study of the system has found no evidence for coalescing material or hot close-in dust or circumstellar matter from an evaporating or exploding planet within a few astronomical units of the mature central star. It has also been hypothesized that the changes in brightness could be signs of activity associated with intelligent extraterrestrial life constructing a Dyson swarm. The scientists involved are very skeptical, however, with others describing it as implausible. KIC 8462852 is not the only star that has large irregular dimmings, but all other such stars are young stellar objects called YSO dippers, which have different dimming patterns. An example of such an object is EPIC 204278916. New light fluctuation events of KIC 8462852 began in the middle of May 2017. Except for a period between late-December 2017 and mid-February 2018 when the star was obscured by the Sun, the fluctuations have continued (As of July 2018).
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  • 15 Nov 2022
Topic Review
San Antonio Independent School District V. Rodriguez
San Antonio Independent School District v. Rodriguez, 411 U.S. 1 (1973), was a case in which the Supreme Court of the United States held that San Antonio Independent School District's financing system, which was based on local property taxes, was not an unconstitutional violation of the Fourteenth Amendment's equal protection clause. The majority opinion, reversing the District Court, stated that the appellees did not sufficiently prove a textual basis, within the US Constitution, supporting the principle that education is a fundamental right. Urging that the school financing system led to wealth-based discrimination, the plaintiffs had argued that the fundamental right to education should be applied to the States, through the Fourteenth Amendment. The Court found that there was no such fundamental right and that the unequal school financing system was not subject to strict scrutiny.
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  • 11 Nov 2022
Topic Review
Mobile Launcher Platform
A mobile launcher platform, also known as mobile launch platform, is a steel structure used to support a large multistage space vehicle which is assembled (stacked) vertically in an integration facility (e.g. the Vehicle Assembly Building) and then transported by a crawler-transporter (CT) to a launch pad. This becomes the support structure for launch. Alternatives to this method include horizontal assembly and transport to the pad, as used by Russia; and assembling the vehicle vertically on the launch pad, as the United States used for smaller launch vehicles. The use of mobile launcher platforms dates back to the "Integrate-Transfer-Launch" (ITL) concept developed in 1965 for the Titan III launched from Cape Canaveral Space Launch Complex 40 and 41, and was adopted in 1966 for the Saturn V vehicle launched from Kennedy Space Center Launch Complex 39. Launch Complex 39 and 41 continue to use this concept.
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