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πŸ”— Capability Based Security

πŸ”— Computing πŸ”— Computer Security πŸ”— Computer Security/Computing

Capability-based security is a concept in the design of secure computing systems, one of the existing security models. A capability (known in some systems as a key) is a communicable, unforgeable token of authority. It refers to a value that references an object along with an associated set of access rights. A user program on a capability-based operating system must use a capability to access an object. Capability-based security refers to the principle of designing user programs such that they directly share capabilities with each other according to the principle of least privilege, and to the operating system infrastructure necessary to make such transactions efficient and secure. Capability-based security is to be contrasted with an approach that uses hierarchical protection domains.

Although most operating systems implement a facility which resembles capabilities, they typically do not provide enough support to allow for the exchange of capabilities among possibly mutually untrusting entities to be the primary means of granting and distributing access rights throughout the system. A capability-based system, in contrast, is designed with that goal in mind.

Capabilities as discussed in this article should not be confused with POSIX 1e/2c "Capabilities". The latter are coarse-grained privileges that cannot be transferred between processes.

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πŸ”— Groom of the Stool

πŸ”— England πŸ”— English Royalty

The Groom of the Stool (formally styled: "Groom of the King's Close Stool") was the most intimate of an English monarch's courtiers, responsible for assisting the king in excretion and ablution.

The physical intimacy of the role naturally led to his becoming a man in whom much confidence was placed by his royal master and with whom many royal secrets were shared as a matter of course. This secret informationβ€”while it would never have been revealed, for it would have led to the discredit of his honourβ€”in turn led to his becoming feared and respected and therefore powerful within the royal court in his own right. The office developed gradually over decades and centuries into one of administration of the royal finances, and under Henry VII, the Groom of the Stool became a powerful official involved in setting national fiscal policy, under the "chamber system".

Later, the office was renamed Groom of the Stole. The Tudor historian David Starkey classes this change as classic Victorianism: "When the Victorians came to look at this office, they spelt it s-t-o-l-e, and imagined all kinds of fictions about elaborate robes draped around the neck of the monarch at the coronation;" however, the change is in fact seen as early as the 17th century.

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πŸ”— Pareto Efficiency

πŸ”— Computer science πŸ”— Economics πŸ”— Engineering πŸ”— Gender Studies

Pareto efficiency or Pareto optimality is a situation where no action or allocation is available that makes one individual better off without making another worse off. The concept is named after Vilfredo Pareto (1848–1923), Italian civil engineer and economist, who used the concept in his studies of economic efficiency and income distribution. The following three concepts are closely related:

  • Given an initial situation, a Pareto improvement is a new situation where some agents will gain, and no agents will lose.
  • A situation is called Pareto-dominated or Pareto-inefficient if there is some possible Pareto improvement that has not been made.
  • A situation is called Pareto-optimal or Pareto-efficient if no change could lead to improved satisfaction for some agent without some other agent losing or, equivalently, if there is no scope for further Pareto improvement (in other words, the situation is not Pareto-dominated).

The Pareto front (also called Pareto frontier or Pareto set) is the set of all Pareto-efficient situations.

Pareto originally used the word "optimal" for the concept, but as it describes a situation where a limited number of people will be made better off under finite resources, and it does not take equality or social well-being into account, it is in effect a definition of and better captured by "efficiency".

In addition to the context of efficiency in allocation, the concept of Pareto efficiency also arises in the context of efficiency in production vs. x-inefficiency: a set of outputs of goods is Pareto-efficient if there is no feasible re-allocation of productive inputs such that output of one product increases while the outputs of all other goods either increase or remain the same.

Pareto efficiency is measured along the production possibility frontier (PPF), which is a graphical representation of all the possible options of output for two products that can be produced using all factors of production.

Besides economics, the notion of Pareto efficiency has been applied to the selection of alternatives in engineering and biology. Each option is first assessed, under multiple criteria, and then a subset of options is ostensibly identified with the property that no other option can categorically outperform the specified option. It is a statement of impossibility of improving one variable without harming other variables in the subject of multi-objective optimization (also termed Pareto optimization).

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πŸ”— List of Generic and Genericized Trademarks

πŸ”— Lists πŸ”— Brands

The following three lists of generic and genericized trademarks are:

  • marks which were originally legally protected trademarks, but have been genericized and have lost their legal status due to becoming generic terms,
  • marks which have been abandoned and are now generic terms
  • marks which are still legally protected as trademarks, at least in some jurisdictions

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πŸ”— Homoiconicity

πŸ”— Computing

In computer programming, homoiconicity (from the Greek words homo- meaning "the same" and icon meaning "representation") is a property of some programming languages. A language is homoiconic if a program written in it can be manipulated as data using the language, and thus the program's internal representation can be inferred just by reading the program itself. For example, a Lisp program is written as a regular Lisp list, and can be manipulated by other Lisp code. In homoiconic languages, all code can be accessed and transformed as data, using the same representation. This property is often summarized by saying that the language treats "code as data".

In a homoiconic language, the primary representation of programs is also a data structure in a primitive type of the language itself. This makes metaprogramming easier than in a language without this property: reflection in the language (examining the program's entities at runtime) depends on a single, homogeneous structure, and it does not have to handle several different structures that would appear in a complex syntax.

As noted above, a commonly cited example is Lisp, which was created to allow for easy list manipulations and where the structure is given by S-expressions that take the form of nested lists. Lisp programs are written in the form of lists; the result is that the program can access its own functions and procedures while running, and programmatically alter itself on the fly. Homoiconic languages typically include full support of syntactic macros, allowing the programmer to express transformations of programs in a concise way. Examples are the programming languages Clojure (a contemporary dialect of Lisp), Rebol (also its successor Red), Refal, Prolog, and more recently Julia.

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πŸ”— Satellite Babies

πŸ”— United States πŸ”— China πŸ”— Sociology

Satellite babies (also called Satellite Children) refer to immigrants’ children who are temporarily sent back to their home country by their parents to be reared by extended family. Typically, the satellite babies are born in the host country and sent back as infants, returning to their parents in time to start schooling or when their parents have established financial stability. Research and media articles on satellite babies have predominantly focused on the topic from a Chinese-American context. Satellite babies have become more prevalent in recent decades due to globalisation, prompting researchers and social workers to raise concerns about the psychological impacts of repeated attachment disruptions and acculturation associated with satellite babies.

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πŸ”— Texas Instruments LPC Speech Chips

πŸ”— Computing

The Texas Instruments LPC Speech Chips are a series of speech synthesizer digital signal processor integrated circuits created by Texas Instruments beginning in 1978. They continued to be developed and marketed for many years, though the speech department moved around several times within TI until finally dissolving in late 2001. The rights to the speech-specific subset of the MSP line, the last remaining line of TI speech products as of 2001, were sold to Sensory, Inc. in October 2001.

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πŸ”— Herfindahl Index

πŸ”— Economics πŸ”— Statistics

The Herfindahl index (also known as Herfindahl–Hirschman Index, HHI, or sometimes HHI-score) is a measure of the size of firms in relation to the industry and an indicator of the amount of competition among them. Named after economists Orris C. Herfindahl and Albert O. Hirschman, it is an economic concept widely applied in competition law, antitrust and also technology management. It is defined as the sum of the squares of the market shares of the firms within the industry (sometimes limited to the 50 largest firms), where the market shares are expressed as fractions. The result is proportional to the average market share, weighted by market share. As such, it can range from 0 to 1.0, moving from a huge number of very small firms to a single monopolistic producer. Increases in the Herfindahl index generally indicate a decrease in competition and an increase of market power, whereas decreases indicate the opposite. Alternatively, if whole percentages are used, the index ranges from 0 to 10,000 "points". For example, an index of .25 is the same as 2,500 points.

The major benefit of the Herfindahl index in relationship to such measures as the concentration ratio is that it gives more weight to larger firms.

The measure is essentially equivalent to the Simpson diversity index, which is a diversity index used in ecology; the inverse participation ratio (IPR) in physics; and the effective number of parties index in politics.

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πŸ”— Randolph Bourne

πŸ”— Biography πŸ”— New York (state) πŸ”— New York (state)/Columbia University

Randolph Silliman Bourne (; May 30, 1886 – December 22, 1918) was a progressive writer and intellectual born in Bloomfield, New Jersey, and a graduate of Columbia University. He is considered to be a spokesman for the young radicals living during World War I. His articles appeared in journals including The Seven Arts and The New Republic. Bourne is best known for his essays, especially his unfinished work "The State," discovered after he died. From this essay (which was published posthumously and included in Untimely Papers) comes the phrase "war is the health of the state" which laments the success of governments in arrogating authority and resources during conflicts.

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πŸ”— The Third Wave Experiment

πŸ”— California πŸ”— California/San Francisco Bay Area πŸ”— Philosophy πŸ”— Psychology πŸ”— Philosophy/Social and political philosophy πŸ”— Sociology

The Third Wave was an experimental social movement created by California high school history teacher Ron Jones in 1967 to explain how the German population could accept the actions of the Nazi regime during the Second World War. While he taught his students about Nazi Germany during his "Contemporary World History" class, Jones found it difficult to explain how the German people could accept the actions of the Nazis, and decided to create a social movement as a demonstration of the appeal of fascism. Over the course of five days, Jones – a member of the SDS, Cubberley United Student Movement sponsor and Black Panthers supporter – conducted a series of exercises in his classroom emphasizing discipline and community, intended to model certain characteristics of the Nazi movement. As the movement grew outside his class and began to number in the hundreds, Jones began to feel that the movement had spiraled out of control. He convinced the students to attend a rally where he claimed that the classroom project was part of a nationwide movement, and that the announcement of a Third Wave presidential candidate would be televised. Upon their arrival, the students were presented with a blank channel. Jones told his students of the true nature of the movement as an experiment in fascism, and presented to them a short film discussing the actions of Nazi Germany.

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