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🔗 Aviation 🔗 Aviation/aircraft

The Airbus Beluga XL (Airbus A330-743L) is a large transport aircraft based on the Airbus A330 airliner. The aircraft entered service with Airbus Transport on 9 January 2020 to replace the Airbus Beluga in the movement of oversized aircraft components, for example wings. The Beluga XL made its first flight on 19 July 2018, and received its type certification on 13 November 2019.

It made its first operational flight on January 9, 2020, and by January 20, had entered full-time service.

🔗 Occupational Safety and Health

ISO 7010 is an International Organization for Standardization technical standard for graphical hazard symbols on hazard and safety signs, including those indicating emergency exits. It uses colours and principles set out in ISO 3864 for these symbols, and is intended to provide "safety information that relies as little as possible on the use of words to achieve understanding." It is distinct from the Globally Harmonized System of Classification and Labelling of Chemicals specified by the United Nations to standardise hazardous material classification and labelling.

As of August 2019, the latest version is ISO 7010:2019. This revision incorporates all previous corrigenda, as well as incorporates water safety signs and beach safety flags previously specified in (the now-withdrawn) ISO 20712.

In computer science, the ski rental problem is a name given to a class of problems in which there is a choice between continuing to pay a repeating cost or paying a one-time cost which eliminates or reduces the repeating cost.

🔗 History 🔗 Visual arts

The Hockney–Falco thesis is a theory of art history, advanced by artist David Hockney and physicist Charles M. Falco. Both claimed that advances in realism and accuracy in the history of Western art since the Renaissance were primarily the result of optical instruments such as the camera obscura, camera lucida, and curved mirrors, rather than solely due to the development of artistic technique and skill. Nineteenth-century artists' use of photography had been well documented. In a 2001 book, Secret Knowledge: Rediscovering the Lost Techniques of the Old Masters, Hockney analyzed the work of the Old Masters and argued that the level of accuracy represented in their work is impossible to create by "eyeballing it". Since then, Hockney and Falco have produced a number of publications on positive evidence of the use of optical aids, and the historical plausibility of such methods. The hypothesis led to a variety of conferences and heated discussions.

🔗 Computer science 🔗 Time

In computer science, time formatting and storage bugs are a class of software bugs which may cause time and date calculation or display to be improperly handled. These are most commonly manifestations of arithmetic overflow, but can also be the result of other issues. The most well-known consequence of bugs of this type is the Y2K problem, but many other milestone dates or times exist that have caused or will cause problems depending on various programming deficiencies.

🔗 United States/U.S. Government 🔗 United States 🔗 Human rights 🔗 Mass surveillance 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Freedom of speech 🔗 Military history/Intelligence 🔗 Law Enforcement

The practice of mass surveillance in the United States dates back to World War I wartime monitoring and censorship of international communications from, to, or which passed through the United States. After the First World War and the Second World War, the surveillance continued, via programs such as the Black Chamber and Project SHAMROCK. The formation and growth of federal law-enforcement and intelligence agencies such as the FBI, CIA, and NSA institutionalized surveillance used to also silence political dissent, as evidenced by COINTELPRO projects which targeted various organizations and individuals. During the Civil Rights Movement era, many individuals put under surveillance orders were first labelled as integrationists then deemed subversive. Other targeted individuals and groups included Native American activists, African American and Chicano liberation movement activists, and anti-war protesters.

The formation of the international UKUSA surveillance agreement of 1946 evolved into the ECHELON collaboration by 1955 of five English-speaking nations, also known as the Five Eyes, and focused on interception of electronic communications, with substantial increases in domestic surveillance capabilities.

Following the September 11th attacks of 2001, domestic and international mass surveillance capabilities grew immensely. Contemporary mass surveillance relies upon annual presidential executive orders declaring a continued State of National Emergency, first signed by George W. Bush on September 14, 2001 and then continued on an annual basis by President Barack Obama, and upon several subsequent national security Acts including the USA PATRIOT Act and FISA Amendment Act's PRISM surveillance program. Critics and political dissenters currently describe the effects of these acts, orders, and resulting database network of Fusion centers as forming a veritable American police state that simply institutionalized the illegal COINTELPRO tactics used to assassinate dissenters and leaders from the 1950s onwards.

Additional surveillance agencies, such as the DHS and the position of Director of National Intelligence have exponentially escalated mass surveillance since 2001. A series of media reports in 2013 revealed more recent programs and techniques employed by the US intelligence community. Advances in computer and information technology allow the creation of huge national databases that facilitate mass surveillance in the United States by DHS managed Fusion centers, the CIA's Terrorist Threat Integration Center (TTIC) program, and the FBI's TSDB.

Mass surveillance databases are also cited as responsible for profiling Latino Americans and contributing to "self-deportation" techniques, or physical deportations by way of the DHS's ICEGang national database.

After World War I, the US Army and State Department established the Black Chamber, also known as the Cipher Bureau, which began operations in 1919. The Black Chamber was headed by Herbert O. Yardley, who had been a leader in the Army's Military Intelligence program. Regarded as a precursor to the National Security Agency, it conducted peacetime decryption of material including diplomatic communications until 1929.

In the advent of World War II, the Office of Censorship was established. The wartime agency monitored "communications by mail, cable, radio, or other means of transmission passing between the United States and any foreign country". This included the 350,000 overseas cables and telegrams and 25,000 international telephone calls made each week. "Every letter that crossed international or U.S. territorial borders from December 1941 to August 1945 was subject to being opened and scoured for details."

With the end of World War II, Project SHAMROCK was established in 1945. The organization was created to accumulate telegraphic data entering and exiting from the United States. Major communication companies such as Western Union, RCA Global and ITT World Communications actively aided the project, allowing American intelligence officials to gain access to international message traffic. Under the project, and many subsequent programs, no precedent had been established for judicial authorisation, and no warrants were issued for surveillance activities. The project was terminated in 1975.

In 1952, President Harry S. Truman established the National Security Agency (NSA) in 1952 for the purposes of collecting, processing, and monitoring intelligence data. The existence of NSA was not known to people as the memorandum by President Truman was classified.

When the Citizens' Commission to Investigate the FBI published stolen FBI documents revealing abuse of intelligence programs in 1971, Senator Frank Church began an investigation into the programs that become known as the Church Committee. The committee sought to investigate intelligence abuses throughout the 1970s. Following a report provided by the committee outlining egregious abuse, in 1976 Congress established the Senate Select Committee on Intelligence. It would later be joined by the Foreign Intelligence Surveillance Court in 1978. The institutions worked to limit the power of the agencies, ensuring that surveillance activities remained within the rule of law.

Following the attacks of September 11, 2001, Congress passed The Patriot Act to strengthen security and intelligence efforts. The act granted the President broad powers on the war against terror, including the power to bypass the FISA Court for surveillance orders in cases of national security. Additionally, mass surveillance activities were conducted alongside various other surveillance programs under the head of President's Surveillance Program. Under pressure from the public, the warrantless wiretapping program was allegedly ended in January 2007.

Many details about the surveillance activities conducted in the United States were revealed in the disclosure by Edward Snowden in June 2013. Regarded as one of the biggest media leaks in the United States, it presented extensive details about the surveillance programs of the NSA, that involved interception of internet data and telephonic calls from over a billion users, across various countries.

🔗 United States 🔗 Biography 🔗 Computer science 🔗 Telecommunications 🔗 Systems 🔗 Biography/science and academia 🔗 Cryptography 🔗 Cryptography/Computer science 🔗 Electronics 🔗 Systems/Systems theory 🔗 Telecommunications/Bell System 🔗 Cycling

Claude Elwood Shannon (April 30, 1916 – February 24, 2001) was an American mathematician, electrical engineer, and cryptographer known as "the father of information theory". Shannon is noted for having founded information theory with a landmark paper, "A Mathematical Theory of Communication", that he published in 1948.

He is also well known for founding digital circuit design theory in 1937, when—as a 21-year-old master's degree student at the Massachusetts Institute of Technology (MIT)—he wrote his thesis demonstrating that electrical applications of Boolean algebra could construct any logical numerical relationship. Shannon contributed to the field of cryptanalysis for national defense during World War II, including his fundamental work on codebreaking and secure telecommunications.

🔗 Greece 🔗 Middle Ages 🔗 Middle Ages/History 🔗 Sicily 🔗 Greece/Byzantine world 🔗 Normandy

The term Norman–Arab–Byzantine culture, Norman–Sicilian culture or, less inclusively, Norman–Arab culture, (sometimes referred to as the "Arab-Norman civilization") refers to the interaction of the Norman, Byzantine Greek, Latin, and Arab cultures following the Norman conquest of the former Emirate of Sicily and North Africa from 1061 to around 1250. The civilization resulted from numerous exchanges in the cultural and scientific fields, based on the tolerance shown by the Normans towards the Latin- and Greek-speaking Christian populations and the former Arab Muslim settlers. As a result, Sicily under the Normans became a crossroad for the interaction between the Norman and Latin Catholic, Byzantine–Orthodox, and Arab–Islamic cultures.

🔗 Computing 🔗 Computer science 🔗 Mathematics

The P versus NP problem is a major unsolved problem in computer science. It asks whether every problem whose solution can be quickly verified can also be solved quickly.

It is one of the seven Millennium Prize Problems selected by the Clay Mathematics Institute, each of which carries a US$1,000,000 prize for the first correct solution.

The informal term quickly, used above, means the existence of an algorithm solving the task that runs in polynomial time, such that the time to complete the task varies as a polynomial function on the size of the input to the algorithm (as opposed to, say, exponential time). The general class of questions for which some algorithm can provide an answer in polynomial time is called "class P" or just "P". For some questions, there is no known way to find an answer quickly, but if one is provided with information showing what the answer is, it is possible to verify the answer quickly. The class of questions for which an answer can be verified in polynomial time is called NP, which stands for "nondeterministic polynomial time".

An answer to the P = NP question would determine whether problems that can be verified in polynomial time can also be solved in polynomial time. If it turned out that P ≠ NP, which is widely believed, it would mean that there are problems in NP that are harder to compute than to verify: they could not be solved in polynomial time, but the answer could be verified in polynomial time.

Aside from being an important problem in computational theory, a proof either way would have profound implications for mathematics, cryptography, algorithm research, artificial intelligence, game theory, multimedia processing, philosophy, economics and many other fields.

🔗 Military history/Early Muslim military history 🔗 Games

The two envelopes problem, also known as the exchange paradox, is a brain teaser, puzzle, or paradox in logic, probability, and recreational mathematics. It is of special interest in decision theory, and for the Bayesian interpretation of probability theory. Historically, it arose as a variant of the necktie paradox. The problem typically is introduced by formulating a hypothetical challenge of the following type:

It seems obvious that there is no point in switching envelopes as the situation is symmetric. However, because you stand to gain twice as much money if you switch while risking only a loss of half of what you currently have, it is possible to argue that it is more beneficial to switch. The problem is to show what is wrong with this argument.