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In philosophy and mathematics, Newcomb's paradox, also referred to as Newcomb's problem, is a thought experiment involving a game between two players, one of whom is able to be able to predict the future.

Newcomb's paradox was created by William Newcomb of the University of California's Lawrence Livermore Laboratory. However, it was first analyzed in a philosophy paper by Robert Nozick in 1969, and appeared in the March 1973 issue of Scientific American, in Martin Gardner's "Mathematical Games." Today it is a much debated problem in the philosophical branch of decision theory.

In rail transportation, a rolling highway or rolling road is a form of combined transport involving the conveying of road trucks by rail, referred to as Ro-La trains. The concept is a form of piggyback transportation.

The technical challenges to implement rolling highways vary from region to region. In North America, the loading gauge is often high enough to accommodate double stack containers, so the height of a semi-trailer on a flatcar is no issue. However, in Europe, except for purpose built lines such as the Channel Tunnel or the Gotthard Base Tunnel, the loading gauge height is much smaller, and it is necessary to transport the trailers with the tires about 30 cm (11.81 in) above the rails, so the trailers cannot be simply parked on the surface of a flat car above the wagon wheels or bogies. Making the wagon wheels smaller limits the maximum speed, so many designs allow the trailer to be transported with its wheels lower than the rail wagon wheels. An early approach in France was the Kangourou wagon with modified trailers. This technology did not survive, due to the market resistance to modified trailers. Today, three designs for these special wagons are in commercial service, "Modalohr", "CargoBeamer" and "Niederflurwagen" .

During a rolling-highway journey, if the drivers accompany the trailer, they are accommodated in a passenger car or a sleeping car. At both ends of the rail link there are purpose-built terminals that allow the train to be easily loaded and unloaded.

The Beale ciphers (or Beale Papers) are a set of three ciphertexts, one of which allegedly states the location of a buried treasure of gold, silver and jewels estimated to be worth over US$43 million as of January 2018. Comprising three ciphertexts, the first (unsolved) text describes the location, the second (solved) ciphertext the content of the treasure, and the third (unsolved) lists the names of the treasure's owners and their next of kin.

The story of the three ciphertexts originates from an 1885 pamphlet detailing treasure being buried by a man named Thomas J. Beale in a secret location in Bedford County, Virginia, in the 1820s. Beale entrusted a box containing the encrypted messages to a local innkeeper named Robert Morriss and then disappeared, never to be seen again. According to the story, the innkeeper opened the box 23 years later, and then decades after that gave the three encrypted ciphertexts to a friend before he died. The friend then spent the next twenty years of his life trying to decode the messages, and was able to solve only one of them which gave details of the treasure buried and the general location of the treasure. The unnamed friend then published all three ciphertexts in a pamphlet which was advertised for sale in the 1880s.

Since the publication of the pamphlet, a number of attempts have been made to decode the two remaining ciphertexts and to locate the treasure, but all efforts have resulted in failure.

There are many arguments that the entire story is a hoax, including the 1980 article "A Dissenting Opinion" by cryptographer Jim Gillogly, and a 1982 scholarly analysis of the Beale Papers and their related story by Joe Nickell, using historical records that cast doubt on the existence of Thomas J. Beale. Nickell also presents linguistic evidence demonstrating that the documents could not have been written at the time alleged (words such as "stampeding", for instance, are of later vintage). His analysis of the writing style showed that Beale was almost certainly James B. Ward, whose 1885 pamphlet brought the Beale Papers to light. Nickell argues that the tale is thus a work of fiction; specifically, a "secret vault" allegory of the Freemasons; James B. Ward was a Mason himself.

Paris syndrome (French: syndrome de Paris, Japanese: パリ症候群, pari shōkōgun) is a condition exhibited by some individuals when visiting or going on vacation to Paris, as a result of extreme shock at discovering that Paris is different from their expectations. The syndrome is characterized by a number of psychiatric symptoms such as acute delusional states, hallucinations, feelings of persecution (perceptions of being a victim of prejudice, aggression, or hostility from others), derealization, depersonalization, anxiety, and also psychosomatic manifestations such as dizziness, tachycardia, sweating, and others, such as vomiting. Similar syndromes include Jerusalem syndrome and Stendhal syndrome. The condition is commonly viewed as a severe form of culture shock. It is particularly noted among Japanese travellers. It is not listed as a recognised condition in the Diagnostic and Statistical Manual of Mental Disorders.

The Athens Charter (French: Charte d'Athènes, Greek: Χάρτα των Αθηνών) was a 1933 document about urban planning published by the Swiss architect Le Corbusier. The work was based upon Le Corbusier’s Ville Radieuse (Radiant City) book of 1935 and urban studies undertaken by the Congrès International d'Architecture Moderne (CIAM) in the early 1930s.

The Charter got its name from location of the fourth CIAM conference in 1933, which, due to the deteriorating political situation in Russia, took place on the S.S. Patris bound for Athens from Marseille. This conference is documented in a film commissioned by Sigfried Giedion and made by his friend Laszlo Moholy-Nagy: "Architects' Congress."

The Charter had a significant impact on urban planning after World War II.

The X68000 (Japanese: エックス ろくまんはっせん, Hepburn: Ekkusu Rokuman Hassen) is a home computer created by Sharp Corporation, first released in 1987, sold only in Japan.

The first model features a 10 MHz Motorola 68000 CPU (hence the name), 1 MB of RAM, and no hard drive; the last model was released in 1993 with a 25 MHz Motorola 68030 CPU, 4 MB of RAM, and optional 80 MB SCSI hard drive. RAM in these systems is expandable to 12 MB, though most games and applications do not require more than 2 MB.

Carpets of Middle-Eastern origin, either from Anatolia, Persia, Armenia, Azerbaijan, the Levant, the Mamluk state of Egypt or Northern Africa, were used as decorative features in Western European paintings from the 14th century onwards. More depictions of Oriental carpets in Renaissance painting survive than actual carpets contemporary with these paintings. Few Middle-Eastern carpets produced before the 17th century remain, though the number of these known has increased in recent decades. Therefore, comparative art-historical research has from its onset in the late 19th century relied on carpets represented in datable European paintings.

The Nuclear Engine for Rocket Vehicle Application (NERVA) was a nuclear thermal rocket engine development program that ran for roughly two decades. Its principal objective was to "establish a technology base for nuclear rocket engine systems to be utilized in the design and development of propulsion systems for space mission application". It was a joint effort of the Atomic Energy Commission (AEC) and the National Aeronautics and Space Administration (NASA), and was managed by the Space Nuclear Propulsion Office (SNPO) until the program ended in January 1973. SNPO was led by NASA's Harold Finger and AEC's Milton Klein.

NERVA had its origins in Project Rover, an AEC research project at the Los Alamos Scientific Laboratory (LASL) with the initial aim of providing a nuclear-powered upper stage for the United States Air Force intercontinental ballistic missiles. Nuclear thermal rocket engines promised to be more efficient than chemical ones. After the formation of NASA in 1958, Project Rover was continued as a civilian project and was reoriented to producing a nuclear powered upper stage for NASA's Saturn V Moon rocket. Reactors were tested at very low power before being shipped to Jackass Flats in the Nevada Test Site. While LASL concentrated on reactor development, NASA built and tested complete rocket engines.

The AEC, SNPO, and NASA considered NERVA a highly successful program in that it met or exceeded its program goals. It demonstrated that nuclear thermal rocket engines were a feasible and reliable tool for space exploration, and at the end of 1968 SNPO deemed that the latest NERVA engine, the XE, met the requirements for a human mission to Mars. It had strong political support from Senators Clinton P. Anderson and Margaret Chase Smith but was cancelled by President Richard Nixon in 1973. Although NERVA engines were built and tested as much as possible with flight-certified components and the engine was deemed ready for integration into a spacecraft, they never flew in space.

Constraint logic programming is a form of constraint programming, in which logic programming is extended to include concepts from constraint satisfaction. A constraint logic program is a logic program that contains constraints in the body of clauses. An example of a clause including a constraint is A(X,Y) :- X+Y>0, B(X), C(Y). In this clause, X+Y>0 is a constraint; A(X,Y), B(X), and C(Y) are literals as in regular logic programming. This clause states one condition under which the statement A(X,Y) holds: X+Y is greater than zero and both B(X) and C(Y) are true.

As in regular logic programming, programs are queried about the provability of a goal, which may contain constraints in addition to literals. A proof for a goal is composed of clauses whose bodies are satisfiable constraints and literals that can in turn be proved using other clauses. Execution is performed by an interpreter, which starts from the goal and recursively scans the clauses trying to prove the goal. Constraints encountered during this scan are placed in a set called constraint store. If this set is found out to be unsatisfiable, the interpreter backtracks, trying to use other clauses for proving the goal. In practice, satisfiability of the constraint store may be checked using an incomplete algorithm, which does not always detect inconsistency.