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🔗 Computer science 🔗 Statistics

A Boltzmann machine (also called stochastic Hopfield network with hidden units) is a type of stochastic recurrent neural network. It is a Markov random field. It was translated from statistical physics for use in cognitive science. The Boltzmann machine is based on stochastic spin-glass model with an external field, i.e., a Sherrington–Kirkpatrick model that is a stochastic Ising Model and applied to machine learning.

Boltzmann machines can be seen as the stochastic, generative counterpart of Hopfield networks. They were one of the first neural networks capable of learning internal representations, and are able to represent and (given sufficient time) solve combinatoric problems.

They are theoretically intriguing because of the locality and Hebbian nature of their training algorithm (being trained by Hebb's rule), and because of their parallelism and the resemblance of their dynamics to simple physical processes. Boltzmann machines with unconstrained connectivity have not proven useful for practical problems in machine learning or inference, but if the connectivity is properly constrained, the learning can be made efficient enough to be useful for practical problems.

They are named after the Boltzmann distribution in statistical mechanics, which is used in their sampling function. That's why they are called "energy based models" (EBM). They were invented in 1985 by Geoffrey Hinton, then a Professor at Carnegie Mellon University, and Terry Sejnowski, then a Professor at Johns Hopkins University.

🔗 Books 🔗 Magic

The Expert at the Card Table, originally titled Artifice, Ruse and Subterfuge at the Card Table: A Treatise on the Science and Art of Manipulating Cards, often referred to simply as Erdnase, is an extensive book on the art of sleight of hand published in 1902 by S. W. Erdnase, a pseudonymous author whose identity has remained a mystery for over a century. As a detailed manual of card sharps, the book is considered to be one of the most influential works on magic or conjuring with cards.

The Expert at the Card Table is the most famous, the most carefully studied book ever published on the art of manipulating cards at gaming tables."

🔗 Books

The Victorian Internet: The Remarkable Story of the Telegraph and the Nineteenth Century's On-Line Pioneers is a 1998 book by Tom Standage. The book was first published in September 1998 through Walker & Company and discusses the development and uses of the electric telegraph during the second half of the 19th century and some of the similarities the telegraph shared with the Internet of the late 20th century.

The central thesis of the book argues that of these two technologies, it was the telegraph that was the more significant, since the ability to communicate globally at all in real-time was a qualitative shift, while according to Standage the change brought on by the modern Internet was merely a quantitative shift.

🔗 Technology 🔗 Engineering 🔗 Sweden

The Mecanum wheel is a omnidirectional wheel design for a land-based vehicle to move in any direction. It is sometimes called the Ilon wheel after its inventor, Bengt Erland Ilon (1923-2008), who came up with the concept while working as an engineer with the Swedish company Mecanum AB, and patented it in the United States on November 13, 1972.

🔗 United States/U.S. Government 🔗 United States 🔗 International relations 🔗 Germany 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Europe 🔗 Italy 🔗 Sociology 🔗 Organizations 🔗 Military history/German military history 🔗 Military history/French military history 🔗 Military history/Cold War 🔗 Cold War 🔗 Military history/Dutch military history 🔗 Rome 🔗 European history 🔗 Military history/Italian military history 🔗 Military history/European military history 🔗 Military history/British military history 🔗 Military history/Post-Cold War 🔗 NATO

Operation Gladio is the codename for clandestine "stay-behind" operations of armed resistance that were organized by the Western Union (WU), and subsequently by NATO and the CIA, in collaboration with several European intelligence agencies. The operation was designed for a potential Warsaw Pact invasion and conquest of Europe. Although Gladio specifically refers to the Italian branch of the NATO stay-behind organizations, "Operation Gladio" is used as an informal name for all of them. Stay-behind operations were prepared in many NATO member countries, and some neutral countries.

During the Cold War, some anti-communist armed groups engaged in the harassment of left-wing parties, torture, terrorist attacks, and massacres in countries such as Italy. The role of the CIA and other intelligence organisations in Gladio—the extent of its activities during the Cold War era and any responsibility for terrorist attacks perpetrated in Italy during the "Years of Lead" (late 1960s–early 1980s)—is the subject of debate.

In 1990, the European Parliament adopted a resolution alleging that military secret services in certain member states were involved in serious terrorism and crime, whether or not their superiors were aware. The resolution also urged investigations by the judiciaries of the countries in which those armies operated, so that their modus operandi and actual extension would be revealed. To date, only Italy, Switzerland and Belgium have had parliamentary inquiries into the matter.

The three inquiries reached differing conclusions as regarded different countries. Guido Salvini, a judge who worked in the Italian Massacres Commission, concluded that some right-wing terrorist organizations of the Years of Lead (La Fenice, National Vanguard and Ordine Nuovo) were the trench troops of a secret army, remotely controlled by exponents of the Italian state apparatus and linked to the CIA. Salvini said that the CIA encouraged them to commit atrocities. The Swiss inquiry found that British intelligence secretly cooperated with their army in an operation named P-26 and provided training in combat, communications, and sabotage. It also discovered that P-26 not only would organize resistance in case of a Soviet invasion, but would also become active should the left succeed in achieving a parliamentary majority. The Belgian inquiry could find no conclusive information on their army. No links between them and terrorist attacks were found, and the inquiry noted that the Belgian secret services refused to provide the identity of agents, which could have eliminated all doubts. A 2000 Italian parliamentary report from the left wing coalition Gruppo Democratici di Sinistra l'Ulivo reported that terrorist massacres and bombings had been organised or promoted or supported by men inside Italian state institutions who were linked to American intelligence. The report also said the United States was guilty of promoting the strategy of tension. Operation Gladio is also suspected to have been activated to counter existing left-wing parliamentary majorities in Europe.

The US State Department published a communiqué in January 2006 that stated claims the United States ordered, supported, or authorized terrorism by stay-behind units, and US-sponsored "false flag" operations are rehashed former Soviet disinformation based on documents that the Soviets forged.

The word gladio is the Italian form of gladius, a type of Roman shortsword.

🔗 Aviation 🔗 Aviation/gliding

Dynamic soaring is a flying technique used to gain energy by repeatedly crossing the boundary between air masses of different velocity. Such zones of wind gradient are generally found close to obstacles and close to the surface, so the technique is mainly of use to birds and operators of radio-controlled gliders, but glider pilots are sometimes able to soar dynamically in meteorological wind shears at higher altitudes.

Dynamic soaring is sometimes confused with slope soaring which is a technique for achieving elevation.

🔗 California 🔗 Mexico 🔗 Geography 🔗 Mythology 🔗 Islands

The Island of California refers to a long-held European misconception, dating from the 16th century, that the Baja California Peninsula was not part of mainland North America but rather a large island (spelled on early maps as Cali Fornia) separated from the continent by a strait now known as the Gulf of California.

One of the most famous cartographic errors in history, it was propagated on many maps during the 17th and 18th centuries, despite contradictory evidence from various explorers. The legend was initially infused with the idea that California was a terrestrial paradise, like the Garden of Eden or Atlantis.

🔗 Mass surveillance 🔗 Novels 🔗 Books 🔗 Novels/Science fiction 🔗 Science Fiction 🔗 Freedom of speech 🔗 Politics 🔗 Socialism

Nineteen Eighty-Four: A Novel, often published as 1984, is a dystopian novel by English novelist George Orwell. It was published in June 1949 by Secker & Warburg as Orwell's ninth and final book completed in his lifetime. The story was mostly written at Barnhill, a farmhouse on the Scottish island of Jura, at times while Orwell suffered from severe tuberculosis. Thematically, Nineteen Eighty-Four centres on the consequences of government over-reach, totalitarianism, mass surveillance, and repressive regimentation of all persons and behaviours within society.

The story takes place in an imagined future, the year 1984, when much of the world has fallen victim to perpetual war, omnipresent government surveillance, historical negationism, and propaganda. Great Britain, known as Airstrip One, has become a province of a superstate named Oceania that is ruled by the Party who employ the Thought Police to persecute individuality and independent thinking. Big Brother, the leader of the Party, enjoys an intense cult of personality despite the fact that he may not exist. The protagonist, Winston Smith, is a diligent and skillful rank-and-file worker and Party member who secretly hates the Party and dreams of rebellion. He enters a forbidden relationship with a co-worker, Julia.

Nineteen Eighty-Four has become a classic literary example of political and dystopian fiction. Many terms used in the novel have entered common usage, including Big Brother, doublethink, thoughtcrime, Newspeak, Room 101, telescreen, 2 + 2 = 5, prole, and memory hole. Nineteen Eighty-Four also popularised the adjective "Orwellian", connoting things such as official deception, secret surveillance, brazenly misleading terminology, and manipulation of recorded history by a totalitarian or authoritarian state. Time included it on its 100 best English-language novels from 1923 to 2005. It was placed on the Modern Library's 100 Best Novels, reaching No. 13 on the editors' list and No. 6 on the readers' list. In 2003, the novel was listed at No. 8 on The Big Read survey by the BBC. Parallels have been drawn between the novel's subject matter and real life instances of totalitarianism, mass surveillance, and violations of freedom of expression among other themes.

🔗 Computing 🔗 Computer science

SCOOP (Simple Concurrent Object Oriented Programming) is a concurrency model designed for the Eiffel programming language, conceived by Eiffel's creator and designer, Bertrand Meyer.

SCOOP defines a way for an object oriented program to be written without the concept of threads, locks, or other typical multiprogramming methods. This allows the compiler or runtime environment to optimize the amount of concurrency as well as eliminate typical design flaws such as deadlock.

The model was first designed in the early 1990s and published in 1993 in the Communications of the ACM An updated version was described in chapter 30 of the book Object-Oriented Software Construction. A prototype implementation was developed in 1995 by Eiffel Software. An article by Compton and Walker provides an overview of SCOOP and describes another early implementation. Nienaltowski, Arslan and Meyer have published a description of the model as of 2003. Work on SCOOP proceeded at the Chair of Software Engineering at ETH Zurich. SCOOP became available as a standard part of EiffelStudio early in 2011.

🔗 Computing

Jensen's Device is a computer programming technique that exploits call by name. It was devised by Danish computer scientist Jørn Jensen, who worked with Peter Naur at Regnecentralen. They worked on the GIER Algol compiler, one of the earliest correct implementations of ALGOL 60. ALGOL 60 used call by name.