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🔗 QSL Card

🔗 Amateur radio

A QSL card is a written confirmation of either a two-way radiocommunication between two amateur radio or citizens band stations; a one-way reception of a signal from an AM radio, FM radio, television or shortwave broadcasting station; or the reception of a two-way radiocommunication by a third party listener. A typical QSL card is the same size and made from the same material as a typical postcard, and most are sent through the mail as such.

QSL card derived its name from the Q code "QSL". A Q code message can stand for a statement or a question (when the code is followed by a question mark). In this case, 'QSL?' (note the question mark) means "Do you confirm receipt of my transmission?" while 'QSL' (without a question mark) means "I confirm receipt of your transmission."

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🔗 Massacre in Korea by Pablo Picasso

🔗 Military history 🔗 Korea 🔗 Visual arts 🔗 Military history/Asian military history 🔗 Spain 🔗 Military history/Korean military history

Massacre in Korea (French: Massacre en Corée) is an expressionistic painting completed on 18 January 1951 by Pablo Picasso. It is Picasso's third anti-war painting and depicts a scene of a massacre of a group of naked women and children by a firing squad. It has been considered to be a condemnation of American intervention in the Korean War. The painting is exhibited in the Musée Picasso in Paris.

🔗 Hy

🔗 Computing 🔗 Computer science 🔗 Computing/Software

Hy (alternately, Hylang) is a programming language, a dialect of the language Lisp designed to interact with the language Python by translating expressions into Python's abstract syntax tree (AST). Hy was introduced at Python Conference (PyCon) 2013 by Paul Tagliamonte.

Similar to Kawa's and Clojure's mapping of s-expressions onto the Java virtual machine (JVM), Hy is meant to operate as a transparent Lisp front end to Python's abstract syntax. Lisp allows operating on code as data (metaprogramming). Thus, Hy can be used to write domain-specific languages. Hy also allows Python libraries, including the standard library, to be imported and accessed alongside Hy code with a compiling step converting the data structure of both into Python's AST.

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  • "Hy" | 2019-08-04 | 850 Upvotes 141 Comments
  • "Hy" | 2016-11-07 | 70 Upvotes 5 Comments

🔗 Plankalkül

🔗 Computing

Plankalkül (German pronunciation: [ˈplaːnkalkyːl]) is a programming language designed for engineering purposes by Konrad Zuse between 1942 and 1945. It was the first high-level programming language to be designed for a computer.

Kalkül is the German term for a formal system—as in Hilbert-Kalkül, the original name for the Hilbert-style deduction system—so Plankalkül refers to a formal system for planning.

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🔗 Monty Hall Problem

🔗 Mathematics 🔗 Television 🔗 Statistics 🔗 Game theory 🔗 Television/Television game shows

The Monty Hall problem is a brain teaser, in the form of a probability puzzle, loosely based on the American television game show Let's Make a Deal and named after its original host, Monty Hall. The problem was originally posed (and solved) in a letter by Steve Selvin to the American Statistician in 1975 (Selvin 1975a), (Selvin 1975b). It became famous as a question from a reader's letter quoted in Marilyn vos Savant's "Ask Marilyn" column in Parade magazine in 1990 (vos Savant 1990a):

Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, say No. 3, which has a goat. He then says to you, "Do you want to pick door No. 2?" Is it to your advantage to switch your choice?

Vos Savant's response was that the contestant should switch to the other door (vos Savant 1990a). Under the standard assumptions, contestants who switch have a 2/3 chance of winning the car, while contestants who stick to their initial choice have only a 1/3 chance.

The given probabilities depend on specific assumptions about how the host and contestant choose their doors. A key insight is that, under these standard conditions, there is more information about doors 2 and 3 than was available at the beginning of the game when door 1 was chosen by the player: the host's deliberate action adds value to the door he did not choose to eliminate, but not to the one chosen by the contestant originally. Another insight is that switching doors is a different action than choosing between the two remaining doors at random, as the first action uses the previous information and the latter does not. Other possible behaviors than the one described can reveal different additional information, or none at all, and yield different probabilities. Yet another insight is that your chance of winning by switching doors is directly related to your chance of choosing the winning door in the first place: if you choose the correct door on your first try, then switching loses; if you choose a wrong door on your first try, then switching wins; your chance of choosing the correct door on your first try is 1/3, and the chance of choosing a wrong door is 2/3.

Many readers of vos Savant's column refused to believe switching is beneficial despite her explanation. After the problem appeared in Parade, approximately 10,000 readers, including nearly 1,000 with PhDs, wrote to the magazine, most of them claiming vos Savant was wrong (Tierney 1991). Even when given explanations, simulations, and formal mathematical proofs, many people still do not accept that switching is the best strategy (vos Savant 1991a). Paul Erdős, one of the most prolific mathematicians in history, remained unconvinced until he was shown a computer simulation demonstrating vos Savant’s predicted result (Vazsonyi 1999).

The problem is a paradox of the veridical type, because the correct choice (that one should switch doors) is so counterintuitive it can seem absurd, but is nevertheless demonstrably true. The Monty Hall problem is mathematically closely related to the earlier Three Prisoners problem and to the much older Bertrand's box paradox.

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🔗 Hurrian songs

🔗 Syria

The Hurrian songs are a collection of music inscribed in cuneiform on clay tablets excavated from the ancient Amorite-Canaanite city of Ugarit, a headland in northern Syria, which date to approximately 1400 BCE. One of these tablets, which is nearly complete, contains the Hurrian hymn to Nikkal (also known as the Hurrian cult hymn or A Zaluzi to the Gods, or simply h.6), making it the oldest surviving substantially complete work of notated music in the world. While the composers' names of some of the fragmentary pieces are known, h.6 is an anonymous work.

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🔗 The Autumn of the Middle Ages

🔗 Books

The Autumn of the Middle Ages, The Waning of the Middle Ages, or Autumntide of the Middle Ages (published in 1919 as Herfsttij der Middeleeuwen and translated into English in 1924, German in 1924, and French in 1932), is the best-known work by the Dutch historian Johan Huizinga.

In the book, Huizinga presents the idea that the exaggerated formality and romanticism of late medieval court society was a defense mechanism against the constantly increasing violence and brutality of general society. He saw the period as one of pessimism, cultural exhaustion, and nostalgia, rather than of rebirth and optimism.

His main conclusion is that the combination of required modernization of statehood governance, stuck in traditionalism, in combination with the exhausting inclusion of an ever-growing corpus of Catholic rites and popular beliefs in daily life, led to the implosion of late medieval society. This provided light to the rise of (religious) individualism, humanism and scientific progress: the renaissance.

The book was nominated for the 1939 Nobel Prize for Literature, but lost to the Finnish writer Frans Eemil Sillanpää.

Huizinga's work later came under some criticism, especially for relying too heavily on evidence from the rather exceptional case of the Burgundian court. Other criticisms include the writing of the book being "old-fashioned" and "too literary".

A new English translation of the book was published in 1996 because of perceived deficiencies in the original translation. The new translation, by Rodney Payton and Ulrich Mammitzsch, was based on the second edition of the Dutch publication in 1921 and compared with the German translation published in 1924.

To mark the centenary of Herfsttij, a new translation by Diane Webb appeared in 2020, published by Leiden University Press: Autumntide of the Middle Ages. According to Benjamin Kaplan, this translation "captures Huizinga's original voice better than either of the two previous English editions". This new English edition also includes for the first time 300 full-colour illustrations of all the works of art Huizinga mentions in his text.

In the 1970s, Radio Netherlands produced an audio series about the book, entitled "Autumn of the Middle Ages: A Six-part History in Words and Music from the Low Countries".

🔗 Gödel, Escher, Bach

🔗 Philosophy 🔗 Philosophy/Philosophical literature 🔗 Books 🔗 Philosophy/Logic

Gödel, Escher, Bach: An Eternal Golden Braid, also known as GEB, is a 1979 book by Douglas Hofstadter. By exploring common themes in the lives and works of logician Kurt Gödel, artist M. C. Escher, and composer Johann Sebastian Bach, the book expounds concepts fundamental to mathematics, symmetry, and intelligence. Through illustration and analysis, the book discusses how, through self-reference and formal rules, systems can acquire meaning despite being made of "meaningless" elements. It also discusses what it means to communicate, how knowledge can be represented and stored, the methods and limitations of symbolic representation, and even the fundamental notion of "meaning" itself.

In response to confusion over the book's theme, Hofstadter emphasized that Gödel, Escher, Bach is not about the relationships of mathematics, art, and music—but rather about how cognition emerges from hidden neurological mechanisms. One point in the book presents an analogy about how individual neurons in the brain coordinate to create a unified sense of a coherent mind by comparing it to the social organization displayed in a colony of ants.

The tagline "a metaphorical fugue on minds and machines in the spirit of Lewis Carroll" was used by the publisher to describe the book.

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🔗 Incident Pit

🔗 Occupational Safety and Health 🔗 Scuba diving

An incident pit is a conceptual pit with sides that become steeper over time and with each new incident until a point of no return is reached. As time moves forward, seemingly innocuous incidents push a situation further toward a bad situation and escape from the incident pit becomes more difficult. An incident pit may or may not have a point of no return such as an event horizon.

It is a term used by divers, as well as engineers, medical personnel, and technology management personnel, to describe these situations and more importantly to avoid becoming ensnared.

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