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Long time nuclear waste warning messages

Linguistics Energy Linguistics/Philosophy of language

Long-time nuclear waste warning messages are intended to deter human intrusion at nuclear waste repositories in the far future, within or above the order of magnitude of 10,000 years. Nuclear semiotics is an interdisciplinary field of research, first done by the Human Interference Task Force since 1981.

A 1996 report from Sandia National Laboratories recommended that any such message should comprise four levels of increasing complexity:

  • Level I: Rudimentary Information: "Something man-made is here"
  • Level II: Cautionary Information: "Something man-made is here and it is dangerous"
  • Level III: Basic Information: Tells what, why, when, where, who, and how
  • Level IV: Complex Information: Highly detailed written records, tables, figures, graphs, maps and diagrams

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The Man Behind AMD's Zen Microarchitecture: Jim Keller

Jim Keller (born 1958/1959) is a microprocessor engineer best known for his work at AMD and Apple. He was the lead architect of the AMD K8 microarchitecture (including the original Athlon 64) and was involved in designing the Athlon (K7) and Apple A4/A5 processors. He was also the coauthor of the specifications for the x86-64 instruction set and HyperTransport interconnect. From 2012 to 2015, he returned to AMD to work on the AMD K12 and Zen microarchitectures.

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The Matthew Effect

Sociology

The Matthew effect of accumulated advantage, Matthew principle, or Matthew effect for short, is sometimes summarized by the adage "the rich get richer and the poor get poorer". The concept is applicable to matters of fame or status, but may also be applied literally to cumulative advantage of economic capital. In the beginning, Matthew effects were primarily focused on the inequality in the way scientists were recognized for their work. However, Norman Storer, of Columbia University, led a new wave of research. He believed he discovered that the inequality that existed in the social sciences also existed in other institutions.

The term was coined by sociologist Robert K. Merton in 1968 and takes its name from the Parable of the talents or minas in the biblical Gospel of Matthew. Merton credited his collaborator and wife, sociologist Harriet Zuckerman, as co-author of the concept of the Matthew effect.

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Johns Hopkins Beast

Systems Robotics Systems/Cybernetics

The Johns Hopkins Beast was a mobile automaton, an early pre-robot, built in the 1960s at the Johns Hopkins University Applied Physics Laboratory. The machine had a rudimentary intelligence and the ability to survive on its own. As it wandered through the white halls of the laboratory, it would seek black wall outlets. When it found one it would plug in and recharge.

The robot was cybernetic. It did not use a computer. Its control circuitry consisted of dozens of transistors controlling analog voltages. It used photocell optics and sonar to navigate. The 2N404 transistors were used to create NOR logic gates that implemented the Boolean logic to tell it what to do when a specific sensor was activated. The 2N404 transistors were also used to create timing gates to tell it how long to do something. 2N1040 Power transistors were used to control the power to the motion treads, the boom, and the charging mechanism.

The original sensors in Mod I were physical touch only. The wall socket was detected by physical switches on the arm that followed the wall. Once detected, two electrical prongs were extended until they entered the wall socket and made the electrical connection to charge the vehicle. The stairway, doors, and pipes on the hall wall were also detected by physical switches and recognized by appropriate logic.

The sonar guidance system was developed for Mod I and improved for Mod II. It used two ultrasonic transducers to determine distance, location within the halls, and obstructions in its path. This provided "The Beast" with bat-like guidance. At this point, it could detect obstructions in the hallway, such as people in the hallway. Once an obstruction was detected, the Beast would slow down and then decide whether to stop or divert around the obstruction. It could also ultrasonically recognize the stairway and doorways to take appropriate action.

An optical guidance system was added to Mod II. This provided, among other capabilities, the ability to optically identify the black wall sockets that contrasted with the white wall.

The Hopkins Beast Autonomous Robot Mod II link below was written by Dr. Ronald McConnell, at that time a co-op student and one of the designers for Mod II.

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Toxic squash syndrome

Chemicals Plants

Cucurbitacin is a class of biochemical compounds that some plants – notably members of the pumpkin and gourd family, Cucurbitaceae – produce and which function as a defence against herbivores. Cucurbitacins are chemically classified as triterpenes, formally derived from cucurbitane, a triterpene hydrocarbon – specifically, from the unsaturated variant cucurbit-5-ene, or 19(10→9β)-abeo-10α-lanost-5-ene. They often occur as glycosides. They and their derivatives have been found in many plant families (including Brassicaceae, Cucurbitaceae, Scrophulariaceae, Begoniaceae, Elaeocarpaceae, Datiscaceae, Desfontainiaceae, Polemoniaceae, Primulaceae, Rubiaceae, Sterculiaceae, Rosaceae, and Thymelaeaceae), in some mushrooms (including Russula and Hebeloma) and even in some marine mollusks.

Cucurbitacins may be a taste deterrent in plants foraged by some animals and in some edible plants preferred by humans, like cucumbers and zucchinis. In laboratory research, cucurbitacins have cytotoxic properties and are under study for their potential biological activities.

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How to get bias into a Wikipedia article

Tilt! How to get bias into a Wikipedia article

To all you budding propagandists in Wikiland: too many of you are working like a bunch of amateurs. Sorry to be so negative, but you have to understand that getting bias into the Wikipedia is a skill; it requires practice, finesse and imagination. It has to be learned; it is not a natural thing, though some have more talent for it than others.

I have been following the Middle East Wikipedia battleground for a few years now, and have been very impressed with the skill of some editors in introducing bias into articles. To ingenuous editors, some of these techniques may seem innocuous enough; in many cases, it is hard to see how proposed edits are biasing an article one way or another. It is, in fact, only in the last few months that I have been able to define what these techniques are and how they work to introduce bias.

The first thing you need to know as a budding propagandist is this: there are two levels at which bias is introduced into the Wikipedia: at the article level, and at the topic level. You need to set your sights high: you don't want to merely bias a single article, you want the entire Wikipedia on your side. Without understanding the importance of topic bias, it is hard to understand many of the article-level techniques, so I will start with the topic level.

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Bertrand Russell

Biography Mathematics Philosophy Philosophy/Logic Philosophy/Social and political philosophy Biography/science and academia Philosophy/Philosophy of science Linguistics Linguistics/Theoretical Linguistics Philosophy/Philosophers Philosophy/Epistemology Sociology Politics of the United Kingdom Philosophy/Philosophy of language Chicago Philosophy/Metaphysics Linguistics/Philosophy of language Philosophy/Analytic philosophy Atheism Biography/Peerage and Baronetage

Bertrand Arthur William Russell, 3rd Earl Russell, (18 May 1872 – 2 February 1970) was a British philosopher, logician, mathematician, historian, writer, essayist, social critic, political activist, and Nobel laureate. At various points in his life, Russell considered himself a liberal, a socialist and a pacifist, although he also confessed that his sceptical nature had led him to feel that he had "never been any of these things, in any profound sense." Russell was born in Monmouthshire into one of the most prominent aristocratic families in the United Kingdom.

In the early 20th century, Russell led the British "revolt against idealism". He is considered one of the founders of analytic philosophy along with his predecessor Gottlob Frege, colleague G. E. Moore and protégé Ludwig Wittgenstein. He is widely held to be one of the 20th century's premier logicians. With A. N. Whitehead he wrote Principia Mathematica, an attempt to create a logical basis for mathematics, the quintessential work of classical logic. His philosophical essay "On Denoting" has been considered a "paradigm of philosophy". His work has had a considerable influence on mathematics, logic, set theory, linguistics, artificial intelligence, cognitive science, computer science (see type theory and type system) and philosophy, especially the philosophy of language, epistemology and metaphysics.

Russell was a prominent anti-war activist and he championed anti-imperialism. Occasionally, he advocated preventive nuclear war, before the opportunity provided by the atomic monopoly had passed and he decided he would "welcome with enthusiasm" world government. He went to prison for his pacifism during World War I. Later, Russell concluded that war against Adolf Hitler's Nazi Germany was a necessary "lesser of two evils" and criticised Stalinist totalitarianism, attacked the involvement of the United States in the Vietnam War and was an outspoken proponent of nuclear disarmament. In 1950, Russell was awarded the Nobel Prize in Literature "in recognition of his varied and significant writings in which he champions humanitarian ideals and freedom of thought".

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Comparison of Afrikaans and Dutch

Languages South Africa

Afrikaans is a daughter language of Dutch and—unlike Netherlands Dutch, Belgian Dutch and Surinamese Dutch—a separate standard language rather than a national variety. As an estimated 90 to 95% of Afrikaans vocabulary is ultimately of Dutch origin, there are few lexical differences between the two languages; however, Afrikaans has a considerably more regular morphology, grammar, and spelling.

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Atbash – Ancient Hebrew Cryptography

Cryptography Cryptography/Computer science Judaism

Atbash (Hebrew: אתבש‎; also transliterated Atbaš) is a monoalphabetic substitution cipher originally used to encrypt the Hebrew alphabet. It can be modified for use with any known writing system with a standard collating order.

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Lambda lifting

Computing

Lambda lifting is a meta-process that restructures a computer program so that functions are defined independently of each other in a global scope. An individual "lift" transforms a local function into a global function. It is a two step process, consisting of;

  • Eliminating free variables in the function by adding parameters.
  • Moving functions from a restricted scope to broader or global scope.

The term "lambda lifting" was first introduced by Thomas Johnsson around 1982 and was historically considered as a mechanism for implementing functional programming languages. It is used in conjunction with other techniques in some modern compilers.

Lambda lifting is not the same as closure conversion. It requires all call sites to be adjusted (adding extra arguments to calls) and does not introduce a closure for the lifted lambda expression. In contrast, closure conversion does not require call sites to be adjusted but does introduce a closure for the lambda expression mapping free variables to values.

The technique may be used on individual functions, in code refactoring, to make a function usable outside the scope in which it was written. Lambda lifts may also be repeated, in order to transform the program. Repeated lifts may be used to convert a program written in lambda calculus into a set of recursive functions, without lambdas. This demonstrates the equivalence of programs written in lambda calculus and programs written as functions. However it does not demonstrate the soundness of lambda calculus for deduction, as the eta reduction used in lambda lifting is the step that introduces cardinality problems into the lambda calculus, because it removes the value from the variable, without first checking that there is only one value that satisfies the conditions on the variable (see Curry's paradox).

Lambda lifting is expensive on processing time for the compiler. An efficient implementation of lambda lifting is O ( n 2 ) {\displaystyle O(n^{2})} on processing time for the compiler.

In the untyped lambda calculus, where the basic types are functions, lifting may change the result of beta reduction of a lambda expression. The resulting functions will have the same meaning, in a mathematical sense, but are not regarded as the same function in the untyped lambda calculus. See also intensional versus extensional equality.

The reverse operation to lambda lifting is lambda dropping.

Lambda dropping may make the compilation of programs quicker for the compiler, and may also increase the efficiency of the resulting program, by reducing the number of parameters, and reducing the size of stack frames. However it makes a function harder to re-use. A dropped function is tied to its context, and can only be used in a different context if it is first lifted.

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