Have a deep view into what people are curious about.

🔗 Aviation 🔗 Crime 🔗 Lists 🔗 Novels 🔗 Correction and Detention Facilities 🔗 Popular Culture 🔗 Novels/Crime

A helicopter prison escape is made when an inmate escapes from a prison by means of a helicopter. This list includes prisoner escapes where a helicopter was used in an attempt to free prisoners from a place of internment, a prison or correctional facility.

One of the earliest instances of using a helicopter to escape a prison was the escape of Joel David Kaplan, nicknamed "Man Fan", on August 19, 1971 from the Santa Martha Acatitla in Mexico. Kaplan was a New York businessman who not only escaped the prison but eventually got out of Mexico and went on to write a book about his experience, The 10-Second Jailbreak.

France has had more recorded helicopter escape attempts than any other country, with at least 11. One of the most notable French jail breaks occurred in 1986, when the wife of bank robber Michel Vaujour studied for months to learn how to fly a helicopter. Using her newly acquired skills, she rented a white helicopter and flew low over Paris to pluck her husband off the roof of his fortress prison. Vaujour was later seriously wounded in a shootout with police, and his pilot wife was arrested.

The record for most helicopter escapes goes to convicted murderer Pascal Payet, who has used helicopters to escape from prisons in 2001, 2003, and most recently 2007.

Another multiple helicopter escapee is Vasilis Paleokostas who on February 22, 2009 escaped for the second time from the same prison. Because of this, many prisons have taken applicable precautions, such as nets or cables strung over open prison courtyards.

🔗 Computer science

In computer science, the shunting-yard algorithm is a method for parsing mathematical expressions specified in infix notation. It can produce either a postfix notation string, also known as Reverse Polish notation (RPN), or an abstract syntax tree (AST). The algorithm was invented by Edsger Dijkstra and named the "shunting yard" algorithm because its operation resembles that of a railroad shunting yard. Dijkstra first described the Shunting Yard Algorithm in the Mathematisch Centrum report MR 34/61.

Like the evaluation of RPN, the shunting yard algorithm is stack-based. Infix expressions are the form of mathematical notation most people are used to, for instance "3 + 4" or "3 + 4 × (2 − 1)". For the conversion there are two text variables (strings), the input and the output. There is also a stack that holds operators not yet added to the output queue. To convert, the program reads each symbol in order and does something based on that symbol. The result for the above examples would be (in Reverse Polish notation) "3 4 +" and "3 4 2 1 − × +", respectively.

The shunting-yard algorithm was later generalized into operator-precedence parsing.

🔗 Chemistry 🔗 Polymers

Retrobright refers to H₂O₂ (hydrogen peroxide) based processes used to remove yellowing from ABS plastics. The usage has also expanded to other retro restoration applications, such as classic and collectible sneaker restoration, where it is referred to by collectors as "sole sauce".

Yellowing in ABS plastic occurs when it is exposed to UV light or excessive heat, which causes photo-oxidation of polymers that breaks polymer chains and causes the plastic to yellow and become brittle.

One method of reversing the yellowed discoloration coined the term (stylized as retr0bright or Retrobrite) was first discovered in 2007 in a German retrocomputing forum, before spreading to an English blog where it was further detailed. The process has been continually refined since.

The long-term effectiveness of these techniques is questioned. Some have discovered the yellowing reappears, and there are concerns that the process weakens and only bleaches the already damaged plastic.

🔗 Sports 🔗 Basketball

Height can significantly influence success in sports, depending on how the design of the sport is linked to factors that are height-biased due to physics and biology. The balance of the intricate array of links will determine the degree to which height plays a role in success, if any.

🔗 Mathematics

In geometry, Monge's theorem, named after Gaspard Monge, states that for any three circles in a plane, none of which is completely inside one of the others, the intersection points of each of the three pairs of external tangent lines are collinear.

For any two circles in a plane, an external tangent is a line that is tangent to both circles but does not pass between them. There are two such external tangent lines for any two circles. Each such pair has a unique intersection point in the extended Euclidean plane. Monge's theorem states that the three such points given by the three pairs of circles always lie in a straight line. In the case of two of the circles being of equal size, the two external tangent lines are parallel. In this case Monge's theorem asserts that the other two intersection points must lie on a line parallel to those two external tangents. In other words, if the two external tangents are considered to intersect at the point at infinity, then the other two intersection points must be on a line passing through the same point at infinity, so the line between them takes the same angle as the external tangent.

🔗 Computing 🔗 Mathematics

The reflected binary code (RBC), also known just as reflected binary (RB) or Gray code after Frank Gray, is an ordering of the binary numeral system such that two successive values differ in only one bit (binary digit). The reflected binary code was originally designed to prevent spurious output from electromechanical switches. Today, Gray codes are widely used to facilitate error correction in digital communications such as digital terrestrial television and some cable TV systems.

🔗 Board and table games

1000 Blank White Cards is a party card game played with cards in which the deck is created as part of the game. Though it has been played by adults in organized groups worldwide, 1000 Blank White Cards is also described as well-suited for children in Hoyle's Rules of Games. Since any game rules are contained on the cards (rather than existing as all-encompassing rules or in a rule book), 1000 Blank White Cards can be considered a sort of nomic. It can be played by any number of players and provides the opportunity for card creation and gameplay outside the scope of a single sitting. Creating new cards during the game, dealing with previous cards' effects, is allowed, and rule modification is encouraged as an integral part of gameplay.

🔗 Economics 🔗 Business 🔗 International development

The O-ring theory of economic development is a model of economic development put forward by Michael Kremer in 1993, which proposes that tasks of production must be executed proficiently together in order for any of them to be of high value. The key feature of this model is positive assortative matching, whereby people with similar skill levels work together.

The name comes from the 1986 Challenger shuttle disaster, a catastrophe caused by the failure of a single O-ring.

Kremer thinks that the O-ring development theory explains why rich countries produce more complicated products, have larger firms and much higher worker productivity than poor countries.

🔗 Medicine

The Krukenberg procedure, also known as the Krukenberg operation, is a surgical technique that converts a forearm stump into a pincer. It was first described in 1917 by the German army surgeon Hermann Krukenberg. It remains in use today for certain special cases but is considered controversial and some surgeons refuse to perform it.

🔗 Biography 🔗 New York City 🔗 Biography/science and academia 🔗 Anthropology 🔗 Anarchism

David Rolfe Graeber (; February 12, 1961 – September 2, 2020) was an American anthropologist, anarchist activist, and author known for his books Debt: The First 5000 Years (2011), The Utopia of Rules (2015) and Bullshit Jobs: A Theory (2018). He was a professor of anthropology at the London School of Economics.

As an assistant professor and associate professor of anthropology at Yale from 1998 to 2007, Graeber specialized in theories of value and social theory. Yale's decision not to rehire him when he would otherwise have become eligible for tenure sparked an academic controversy. He went on to become, from 2007 to 2013, reader in social anthropology at Goldsmiths, University of London.

His activism includes protests against the 3rd Summit of the Americas in Quebec City in 2001, and at the 2002 World Economic Forum in New York City. Graeber was a leading figure in the Occupy Wall Street movement, and is sometimes credited with having coined the slogan "we are the 99%". He accepted credit for the description "the 99%" but said that others had expanded it into the slogan.