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🔗 Aviation 🔗 New Zealand

On 22 December 1978, a small Cessna 188 aircraft, piloted by Jay Prochnow, became lost over the Pacific Ocean. The only other aircraft in the area that was able to assist was a commercial Air New Zealand flight. After several hours of searching, the crew of the Air New Zealand flight located the lost Cessna and led it to Norfolk Island, where the plane landed safely.

🔗 Mathematics

The Banach–Tarski paradox is a theorem in set-theoretic geometry, which states the following: Given a solid ball in 3‑dimensional space, there exists a decomposition of the ball into a finite number of disjoint subsets, which can then be put back together in a different way to yield two identical copies of the original ball. Indeed, the reassembly process involves only moving the pieces around and rotating them without changing their shape. However, the pieces themselves are not "solids" in the usual sense, but infinite scatterings of points. The reconstruction can work with as few as five pieces.

A stronger form of the theorem implies that given any two "reasonable" solid objects (such as a small ball and a huge ball), the cut pieces of either one can be reassembled into the other. This is often stated informally as "a pea can be chopped up and reassembled into the Sun" and called the "pea and the Sun paradox".

The reason the Banach–Tarski theorem is called a paradox is that it contradicts basic geometric intuition. "Doubling the ball" by dividing it into parts and moving them around by rotations and translations, without any stretching, bending, or adding new points, seems to be impossible, since all these operations ought, intuitively speaking, to preserve the volume. The intuition that such operations preserve volumes is not mathematically absurd and it is even included in the formal definition of volumes. However, this is not applicable here because in this case it is impossible to define the volumes of the considered subsets. Reassembling them reproduces a volume, which happens to be different from the volume at the start.

Unlike most theorems in geometry, the proof of this result depends in a critical way on the choice of axioms for set theory. It can be proven using the axiom of choice, which allows for the construction of non-measurable sets, i.e., collections of points that do not have a volume in the ordinary sense, and whose construction requires an uncountable number of choices.

It was shown in 2005 that the pieces in the decomposition can be chosen in such a way that they can be moved continuously into place without running into one another.

🔗 United States 🔗 Freedom of speech

Free speech zones (also known as First Amendment zones, free speech cages, and protest zones) are areas set aside in public places for the purpose of political protesting. The First Amendment to the United States Constitution states that "Congress shall make no law ... abridging ... the right of the people peaceably to assemble, and to petition the Government for a redress of grievances." The existence of free speech zones is based on U.S. court decisions stipulating that the government may reasonably regulate the time, place, and manner – but not content – of expression.

The Supreme Court has developed a four-part analysis to evaluate the constitutionality of time, place and manner (TPM) restrictions. To pass muster under the First Amendment, TPM restrictions must be neutral with respect to content, be narrowly drawn, serve a significant government interest, and leave open alternative channels of communication. Application of this four-part analysis varies with the circumstances of each case, and typically requires lower standards for the restriction of obscenity and fighting words.

Free speech zones have been used at a variety of political gatherings. The stated purpose of free speech zones is to protect the safety of those attending the political gathering, or for the safety of the protesters themselves. Critics, however, suggest that such zones are "Orwellian", and that authorities use them in a heavy-handed manner to censor protesters by putting them literally out of sight of the mass media, hence the public, as well as visiting dignitaries. Though authorities generally deny specifically targeting protesters, on a number of occasions, these denials have been contradicted by subsequent court testimony. The American Civil Liberties Union (ACLU) has filed, with various degrees of success and failure, a number of lawsuits on the issue.

Though free speech zones existed prior to the Presidency of George W. Bush, it was during Bush's presidency that their scope was greatly expanded. These zones continued through the presidency of Barack Obama; he signed a bill in 2012 that expanded the power of the Secret Service to restrict speech and make arrests.

Many colleges and universities earlier instituted free speech zone rules during the Vietnam-era protests of the 1960s and 1970s. In recent years, a number of them have revised or removed these restrictions following student protests and lawsuits.

🔗 United States 🔗 Canada 🔗 Micronations 🔗 Canada/Geography of Canada 🔗 United States/New Hampshire

The Republic of Indian Stream or Indian Stream Republic was an unrecognized constitutional republic in North America, along the section of the border that divides the current Canadian province of Quebec from the U.S. state of New Hampshire. It existed from July 9, 1832, to August 5, 1835. Described as "Indian Stream Territory, so-called" by the United States census-taker in 1830, the area was named for Indian Stream, a small watercourse. It had an organized elected government and constitution and served about three hundred citizens.

🔗 Medicine

The choking game (also known as the fainting game and a wide variety of slang terms) refers to intentionally cutting off oxygen to the brain with the goal of inducing temporary loss of consciousness and euphoria.

🔗 Computer science 🔗 Databases 🔗 Databases/Computer science

R-trees are tree data structures used for spatial access methods, i.e., for indexing multi-dimensional information such as geographical coordinates, rectangles or polygons. The R-tree was proposed by Antonin Guttman in 1984 and has found significant use in both theoretical and applied contexts. A common real-world usage for an R-tree might be to store spatial objects such as restaurant locations or the polygons that typical maps are made of: streets, buildings, outlines of lakes, coastlines, etc. and then find answers quickly to queries such as "Find all museums within 2 km of my current location", "retrieve all road segments within 2 km of my location" (to display them in a navigation system) or "find the nearest gas station" (although not taking roads into account). The R-tree can also accelerate nearest neighbor search for various distance metrics, including great-circle distance.

🔗 Novels 🔗 Novels/Science fiction

We (Russian: Мы, romanized: My) is a dystopian novel by Russian writer Yevgeny Zamyatin, written 1920–1921. The novel was first published as an English translation by Gregory Zilboorg in 1924 by E. P. Dutton in New York. The novel describes a world of harmony and conformity within a united totalitarian state. George Orwell claimed that Aldous Huxley's 1931 Brave New World must be partly derived from We, but Huxley denied it.

🔗 Aviation 🔗 Military history 🔗 Military history/Military aviation 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Aviation/aircraft 🔗 Military history/World War II 🔗 Japan 🔗 Japan/Japanese military history 🔗 Military history/Asian military history 🔗 Military history/Japanese military history

A Fu-Go (ふ号[兵器], fugō [heiki], lit. "Code Fu [Weapon]"), or fire balloon (風船爆弾, fūsen bakudan, lit. "balloon bomb"), was a weapon launched by Japan during World War II. A hydrogen balloon with a load varying from a 33 lb (15 kg) antipersonnel bomb to one 26-pound (12 kg) incendiary bomb and four 11 lb (5.0 kg) incendiary devices attached, it was designed as a cheap weapon intended to make use of the jet stream over the Pacific Ocean and drop bombs on American cities, forests, and farmland. Canada and Mexico reported fire balloon sightings as well.

The Japanese fire balloon was the first ever weapon possessing intercontinental range (the second being the Convair B-36 Peacemaker and the third being the R-7 ICBM). The Japanese balloon attacks on North America were at that time the longest ranged attacks ever conducted in the history of warfare, a record which was not broken until the 1982 Operation Black Buck raids during the Falkland Islands War.

The balloons were intended to instill fear and terror in the U.S., though the bombs were relatively ineffective as weapons of destruction due to extreme weather conditions.

🔗 Psychology 🔗 History of Science 🔗 Occult

Physiognomy (from the Greek φύσις, 'physis', meaning "nature", and 'gnomon', meaning "judge" or "interpreter") is the practice of assessing a person's character or personality from their outer appearance—especially the face. The term can also refer to the general appearance of a person, object, or terrain without reference to its implied characteristics—as in the physiognomy of an individual plant (see plant life-form) or of a plant community (see vegetation).

Physiognomy as a practice meets the contemporary definition of pseudoscience and it is so regarded among academic circles because of its unsupported claims; popular belief in the practice of physiognomy is nonetheless still widespread and modern advances in artificial intelligence have sparked renewed interest in the field of study. The practice was well-accepted by ancient Greek philosophers, but fell into disrepute in the Middle Ages while practised by vagabonds and mountebanks. It revived and was popularised by Johann Kaspar Lavater, before falling from favor in the late 19th century. Physiognomy in the 19th century is particularly noted as a basis for scientific racism. Physiognomy as it is understood today is a subject of renewed scientific interest, especially as it relates to machine learning and facial recognition technologyThe main interest for scientists today are the risks, including privacy concerns, of physiognomy in the context of facial recognition algorithms.

Physiognomy is sometimes referred to as 'anthroposcopy', a term originating in the 19th century.

🔗 Computing

When writing firmware for an embedded system, immunity-aware programming refers to programming techniques which improve the tolerance of transient errors in the program counter or other modules of a program that would otherwise lead to failure. Transient errors are typically caused by single event upsets, insufficient power, or by strong electromagnetic signals transmitted by some other "source" device.

Immunity-aware programming is an example of defensive programming and EMC-aware programming. Although most of these techniques apply to the software in the "victim" device to make it more reliable, a few of these techniques apply to software in the "source" device to make it emit less unwanted noise.