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🔗 Germany 🔗 Architecture 🔗 Poland

Drzymała's wagon (Polish: wóz Drzymały) was a house on wheels built by Michał Drzymała as a protest against Imperial Germany's policy of Germanization in its Polish territories. Its owner, the peasant Michał Drzymała (1857-1937), was not only able to circumvent German building regulations by moving his home every day, but with his wagon-home became a Polish folk hero during the Partitions of Poland.

In 1886, by resolution of the Prussian Landtag, a Settlement Commission had been established to encourage German settlement in the Province of Posen and West Prussia. The Commission was empowered to purchase vacant property of the Polish szlachta and sell it to approved German applicants. The Prussian government regarded this as a measure designed to counteract the German "Flight from the East" (Ostflucht) and reduce the number of Poles, who were migrating to the area in hundreds of thousands looking for work. In Polish eyes, the establishment of the Commission was an aggressive measure designed to drive Poles from their lands.

While the campaign against Polish landownership largely missed its aims, it produced a strong opposition with its own hero, Drzymała. In 1904 he purchased a plot of land in Pogradowitz in the Posen district of Bomst, but found that the newly implemented Prussian Feuerstättengesetz ("furnace law") enabled local officials to deny him as a Pole the permission to build a permanent dwelling with an oven on his land. The law considered any place of stay a house if it stayed in one place for more than 24 hours. To get around the rule, he set himself up in a former circus caravan and for several years tenaciously defied in the courts all attempts to remove him. Each day, Drzymała moved the wagon a short distance, thereby exploiting the loophole and avoiding any legal penalties, until in 1909 he was able to buy an existent farmhouse nearby.

The case attracted publicity all over Germany. The German Kulturkampf measures and the Colonization Commission ultimately succeeded in stimulating the Polish national sentiment that they had been designed to suppress.

🔗 Germany 🔗 Military history 🔗 Military history/World War II 🔗 Military history/German military history 🔗 Jewish history 🔗 Military history/European military history

Kristallnacht (German pronunciation: [kʁɪsˈtalnaχt]) or the Night of Broken Glass, also called the November Pogrom(s), was a pogrom against Jews carried out by SA paramilitary forces and civilians throughout Nazi Germany on 9–10 November 1938. The German authorities looked on without intervening. The name Kristallnacht ("Crystal Night") comes from the shards of broken glass that littered the streets after the windows of Jewish-owned stores, buildings and synagogues were smashed.

Jewish homes, hospitals and schools were ransacked as the attackers demolished buildings with sledgehammers. The rioters destroyed 267 synagogues throughout Germany, Austria and the Sudetenland. Over 7,000 Jewish businesses were damaged or destroyed, and 30,000 Jewish men were arrested and incarcerated in concentration camps. British historian Martin Gilbert wrote that no event in the history of German Jews between 1933 and 1945 was so widely reported as it was happening, and the accounts from foreign journalists working in Germany sent shockwaves around the world. The Times of London observed on 11 November 1938: "No foreign propagandist bent upon blackening Germany before the world could outdo the tale of burnings and beatings, of blackguardly assaults on defenceless and innocent people, which disgraced that country yesterday."

The pretext for the attacks was the assassination of the Nazi German diplomat Ernst vom Rath by Herschel Grynszpan, a 17-year-old German-born Polish Jew living in Paris. Estimates of fatalities caused by the attacks have varied. Early reports estimated that 91 Jews had been murdered. Modern analysis of German scholarly sources puts the figure much higher; when deaths from post-arrest maltreatment and subsequent suicides are included, the death toll climbs into the hundreds, with Richard J. Evans estimating 638 suicide deaths. Historians view Kristallnacht as a prelude to the Final Solution and the murder of six million Jews during the Holocaust.

🔗 United States 🔗 Books 🔗 Civil Rights Movement

The Negro Motorist Green Book (also The Negro Motorist Green-Book, The Negro Travelers' Green Book, or simply the Green Book) was an annual guidebook for African-American roadtrippers. It was originated and published by African American, New York City mailman Victor Hugo Green from 1936 to 1966, during the era of Jim Crow laws, when open and often legally prescribed discrimination against African Americans especially and other non-whites was widespread. Although pervasive racial discrimination and poverty limited black car ownership, the emerging African-American middle class bought automobiles as soon as they could, but faced a variety of dangers and inconveniences along the road, from refusal of food and lodging to arbitrary arrest. In response, Green wrote his guide to services and places relatively friendly to African-Americans, eventually expanding its coverage from the New York area to much of North America, as well as founding a travel agency.

Many black Americans took to driving, in part to avoid segregation on public transportation. As the writer George Schuyler put it in 1930, "all Negroes who can do so purchase an automobile as soon as possible in order to be free of discomfort, discrimination, segregation and insult." Black Americans employed as athletes, entertainers, and salesmen also traveled frequently for work purposes.

African-American travelers faced hardships such as white-owned businesses refusing to serve them or repair their vehicles, being refused accommodation or food by white-owned hotels, and threats of physical violence and forcible expulsion from whites-only "sundown towns". Green founded and published the Green Book to avoid such problems, compiling resources "to give the Negro traveler information that will keep him from running into difficulties, embarrassments and to make his trip more enjoyable." The maker of a 2019 documentary film about the book offered this summary: "Everyone I was interviewing talked about the community that the Green Book created: a kind of parallel universe that was created by the book and this kind of secret road map that the Green Book outlined".

From a New York-focused first edition published in 1936, Green expanded the work to cover much of North America, including most of the United States and parts of Canada, Mexico, the Caribbean, and Bermuda. The Green Book became "the bible of black travel during Jim Crow", enabling black travelers to find lodgings, businesses, and gas stations that would serve them along the road. It was little known outside the African-American community. Shortly after passage of the Civil Rights Act of 1964, which outlawed the types of racial discrimination that had made the Green Book necessary, publication ceased and it fell into obscurity. There has been a revived interest in it in the early 21st century in connection with studies of black travel during the Jim Crow era.

Four issues (1940, 1947, 1954, and 1963) have been republished in facsimile (as of December 2017), and have sold well. Twenty-three additional issues have now been digitized by the New York Public Library Digital Collections.

🔗 Numismatics 🔗 Numismatics/Cryptocurrency 🔗 Cryptocurrency

Base58 is a group of binary-to-text encoding schemes used to represent large integers as alphanumeric text, introduced by Satoshi Nakamoto for use with Bitcoin. It has since been applied to other cryptocurrencies and applications. It is similar to Base64 but has been modified to avoid both non-alphanumeric characters and letters which might look ambiguous when printed. It is therefore designed for human users who manually enter the data, copying from some visual source, but also allows easy copy and paste because a double-click will usually select the whole string.

Compared with Base64, the following similar-looking letters are omitted: 0 (zero), O (capital o), I (capital i) and l (lower case L) as well as the non-alphanumeric characters + (plus) and / (slash). In contrast with Base64, the digits of the encoding do not line up well with byte boundaries of the original data. For this reason, the method is well-suited to encode large integers, but not designed to encode longer portions of binary data. The actual order of letters in the alphabet depends on the application, which is the reason why the term “Base58” alone is not enough to fully describe the format. A variant, Base56, excludes 1 (one) and o (lowercase o) compared with Base 58.

Base58Check is a Base58 encoding format that unambiguously encodes the type of data in the first few characters and includes an error detection code in the last few characters.

🔗 Statistics

A set of dice is nontransitive if it contains three dice, A, B, and C, with the property that A rolls higher than B more than half the time, and B rolls higher than C more than half the time, but it is not true that A rolls higher than C more than half the time. In other words, a set of dice is nontransitive if the binary relation – X rolls a higher number than Y more than half the time – on its elements is not transitive.

It is possible to find sets of dice with the even stronger property that, for each die in the set, there is another die that rolls a higher number than it more than half the time. Using such a set of dice, one can invent games which are biased in ways that people unused to nontransitive dice might not expect (see Example).

🔗 Telecommunications 🔗 Meteorology 🔗 Astronomy 🔗 Solar System

The solar storm of 1859 (also known as the Carrington Event) was a powerful geomagnetic storm during solar cycle 10 (1855–1867). A solar coronal mass ejection (CME) hit Earth's magnetosphere and induced the largest geomagnetic storm on record, September 1–2, 1859. The associated "white light flare" in the solar photosphere was observed and recorded by British astronomers Richard C. Carrington (1826–1875) and Richard Hodgson (1804–1872). The storm caused strong auroral displays and wrought havoc with telegraph systems. The now-standard unique IAU identifier for this flare is SOL1859-09-01.

A solar storm of this magnitude occurring today would cause widespread electrical disruptions, blackouts and damage due to extended outages of the electrical grid. The solar storm of 2012 was of similar magnitude, but it passed Earth's orbit without striking the planet, missing by nine days.

🔗 Aviation 🔗 Aviation/aircraft engine

The Coffman engine starter (also known as a "shotgun starter") was a starting system used on many piston engines in aircraft and armored vehicles of the 1930s and 1940s. It used a cordite cartridge to move a piston, which cranked the engine. The Coffman system was one of the most common brands; another was the Breeze cartridge system, which was produced under Coffman patents. Most American military aircraft and tanks which used radial engines were equipped with this system. Some versions of the Rolls-Royce Merlin engine used in the British Supermarine Spitfire used the Coffman system as a starter. The Hawker Typhoon also used the Coffman system to start its Napier Sabre engine.

Cartridge starters used on a number of jet engines, including such engines as the Rolls-Royce Avon, which were used in the English Electric Canberra and Hawker Hunter, used a high gas volume cartridge driving a turbine instead of a piston.

Some Snowcat and similar vehicles used in extreme low temperatures were historically equipped with cartridge start.

🔗 Cognitive science 🔗 Neuroscience

Sparse distributed memory (SDM) is a mathematical model of human long-term memory introduced by Pentti Kanerva in 1988 while he was at NASA Ames Research Center. It is a generalized random-access memory (RAM) for long (e.g., 1,000 bit) binary words. These words serve as both addresses to and data for the memory. The main attribute of the memory is sensitivity to similarity, meaning that a word can be read back not only by giving the original write address but also by giving one close to it, as measured by the number of mismatched bits (i.e., the Hamming distance between memory addresses).

SDM implements transformation from logical space to physical space using distributed data representation and storage, similarly to encoding processes in human memory. A value corresponding to a logical address is stored into many physical addresses. This way of storing is robust and not deterministic. A memory cell is not addressed directly. If input data (logical addresses) are partially damaged at all, we can still get correct output data.

The theory of the memory is mathematically complete and has been verified by computer simulation. It arose from the observation that the distances between points of a high-dimensional space resemble the proximity relations between concepts in human memory. The theory is also practical in that memories based on it can be implemented with conventional RAM-memory elements.

🔗 Birds

Brood parasites are organisms that rely on others to raise their young. The strategy appears among birds, insects and fish. The brood parasite manipulates a host, either of the same or of another species, to raise its young as if it were its own, using brood mimicry, for example by having eggs that resemble the host's (egg mimicry).

Brood parasitism relieves the parasitic parents from the investment of rearing young or building nests for the young, enabling them to spend more time on other activities such as foraging and producing further offspring. Bird parasite species mitigate the risk of egg loss by distributing eggs amongst a number of different hosts. As this behaviour damages the host, it often results in an evolutionary arms race between parasite and host as the pair of species coevolve.

The strength of defenses and counter-adaptation rely on the host/parasitic species' ability to evolve; some host species have very strong rejection defenses resulting in the parasitic species evolving to have very close mimicry. In other species, hosts do not show rejection defenses and as a result, the parasitic species will show no evolved trait (example: egg mimicry).

🔗 Chess 🔗 Hungary 🔗 Turkey

The Turk, also known as the Mechanical Turk or Automaton Chess Player (German: Schachtürke, "chess Turk"; Hungarian: A Török), was a fake chess-playing machine constructed in the late 18th century. From 1770 until its destruction by fire in 1854 it was exhibited by various owners as an automaton, though it was eventually revealed to be an elaborate hoax. Constructed and unveiled in 1770 by Wolfgang von Kempelen (Hungarian: Kempelen Farkas; 1734–1804) to impress the Empress Maria Theresa of Austria, the mechanism appeared to be able to play a strong game of chess against a human opponent, as well as perform the knight's tour, a puzzle that requires the player to move a knight to occupy every square of a chessboard exactly once.

The Turk was in fact a mechanical illusion that allowed a human chess master hiding inside to operate the machine. With a skilled operator, the Turk won most of the games played during its demonstrations around Europe and the Americas for nearly 84 years, playing and defeating many challengers including statesmen such as Napoleon Bonaparte and Benjamin Franklin. The device was later purchased in 1804 and exhibited by Johann Nepomuk Mälzel. The chess masters who secretly operated it included Johann Allgaier, Boncourt, Aaron Alexandre, William Lewis, Jacques Mouret, and William Schlumberger, but the operators within the mechanism during Kempelen's original tour remain a mystery.