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🔗 History 🔗 Middle Ages 🔗 Middle Ages/History

The Nine Worthies are nine historical, scriptural, and legendary personages who personify the ideals of chivalry established in the Middle Ages, whose lives were deemed a valuable study for aspirants to chivalric status. All were commonly referred to as 'Princes', regardless of their historical titles. In French they are called Les Neuf Preux or "Nine Valiants", giving a more specific idea of the moral virtues they exemplified: those of soldierly courage and generalship. In Italy they are i Nove Prodi.

The Nine Worthies include three pagans (Hector, Alexander the Great and Julius Caesar), three Jews (Joshua, David and Judas Maccabeus) and three Christians (King Arthur, Charlemagne and Godfrey of Bouillon).

🔗 Mathematics 🔗 Statistics

In statistical hypothesis testing, a type I error is the rejection of a true null hypothesis (also known as a "false positive" finding or conclusion), while a type II error is the non-rejection of a false null hypothesis (also known as a "false negative" finding or conclusion). Much of statistical theory revolves around the minimization of one or both of these errors, though the complete elimination of either is a statistical impossibility for non-deterministic algorithms. By selecting a low threshold (cut-off) value and modifying the alpha (p) level, the quality of the hypothesis test can be increased. The knowledge of Type I errors and Type II errors is widely used in medical science, biometrics and computer science.

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Intelligence 🔗 Military history/Cold War 🔗 Military history/Australia, New Zealand and South Pacific military history 🔗 Military history/Canadian military history 🔗 Military history/European military history 🔗 Military history/British military history

The Five Eyes (FVEY) is an anglophone intelligence alliance comprising Australia, Canada, New Zealand, the United Kingdom and the United States. These countries are parties to the multilateral UKUSA Agreement, a treaty for joint cooperation in signals intelligence.

The origins of the FVEY can be traced back to the post–World War II period, when the Atlantic Charter was issued by the Allies to lay out their goals for a post-war world. During the course of the Cold War, the ECHELON surveillance system was initially developed by the FVEY to monitor the communications of the former Soviet Union and the Eastern Bloc, although it is now used to monitor billions of private communications worldwide.

In the late 1990s, the existence of ECHELON was disclosed to the public, triggering a major debate in the European Parliament and, to a lesser extent, the United States Congress. As part of efforts in the ongoing War on Terror since 2001, the FVEY further expanded their surveillance capabilities, with much emphasis placed on monitoring the World Wide Web. The former NSA contractor Edward Snowden described the Five Eyes as a "supra-national intelligence organisation that does not answer to the known laws of its own countries". Documents leaked by Snowden in 2013 revealed that the FVEY has been spying on one another's citizens and sharing the collected information with each other in order to circumvent restrictive domestic regulations on surveillance of citizens.

In spite of continued controversy over its methods, the Five Eyes relationship remains one of the most comprehensive known espionage alliances in history.

Since processed intelligence is gathered from multiple sources, the intelligence shared is not restricted to signals intelligence (SIGINT) and often involves defence intelligence as well as human intelligence (HUMINT) and geospatial intelligence (GEOINT). The following table provides an overview of most of the FVEY agencies involved in such forms of data sharing.

🔗 Disambiguation

Pater Noster, or the Lord's Prayer, is a prayer in Christianity.

Pater Noster or Paternoster may also refer to:

🔗 Mathematics

In mathematics, 0.999... (also written as 0.9, among other ways) denotes the repeating decimal consisting of infinitely many 9s after the decimal point (and one 0 before it). This repeating decimal represents the smallest number no less than every decimal number in the sequence (0.9, 0.99, 0.999, ...). This number is equal to 1. In other words, "0.999..." and "1" represent the same number. There are many ways of showing this equality, from intuitive arguments to mathematically rigorous proofs. The technique used depends on the target audience, background assumptions, historical context, and preferred development of the real numbers, the system within which 0.999... is commonly defined. (In other systems, 0.999... can have the same meaning, a different definition, or be undefined.)

More generally, every nonzero terminating decimal has two equal representations (for example, 8.32 and 8.31999...), which is a property of all base representations. The utilitarian preference for the terminating decimal representation contributes to the misconception that it is the only representation. For this and other reasons—such as rigorous proofs relying on non-elementary techniques, properties, or disciplines—some people can find the equality sufficiently counterintuitive that they question or reject it. This has been the subject of several studies in mathematics education.

🔗 Physics 🔗 Astronomy

In astrophysics and physical cosmology, Olbers' paradox, named after the German astronomer Heinrich Wilhelm Olbers (1758–1840), also known as the "dark night sky paradox", is the argument that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. In the hypothetical case that the universe is static, homogeneous at a large scale, and populated by an infinite number of stars, any line of sight from Earth must end at the surface of a star and hence the night sky should be completely illuminated and very bright. This contradicts the observed darkness and non-uniformity of the night.

The darkness of the night sky is one of the pieces of evidence for a dynamic universe, such as the Big Bang model. That model explains the observed non-uniformity of brightness by invoking spacetime's expansion, which lengthens the light originating from the Big Bang to microwave levels via a process known as redshift; this microwave radiation background has wavelengths much longer than those of visible light, and so appears dark to the naked eye. Other explanations for the paradox have been offered, but none have wide acceptance in cosmology.

🔗 California 🔗 California/San Francisco Bay Area 🔗 Internet

The "PayPal Mafia" is a group of former PayPal employees and founders who have since founded and developed additional technology companies such as Tesla Motors, LinkedIn, Palantir Technologies, SpaceX, YouTube, Yelp, and Yammer. Most of the members attended Stanford University or University of Illinois at Urbana–Champaign at some point in their studies.

🔗 China 🔗 Mythology 🔗 Taoism

Erlang Shen (二郎神), or Erlang is a Chinese God with a third truth-seeing eye in the middle of his forehead.

Er-lang Shen may be a deified version of several semi-mythical folk heroes who help regulate China's torrential floods dating variously from the Qin, Sui, and Jin dynasties. A later Buddhist source identifies him as the second son of the Northern Heavenly King Vaishravana.

In the Ming semi-mythical novels Creation of the Gods and Journey to the West, Erlang Shen is the nephew of the Jade Emperor. In the former, he assists the Zhou army in defeating the Shang. In the latter, he is the second son of a mortal and Jade emperor's sister. In the legend, he is known as the greatest warrior god of heaven.

🔗 Computer science

The Q notation is a succinct way to specify the parameters of a binary fixed point number format. A number of other notations have been used for the same purpose.

🔗 United States 🔗 Law

Hush-A-Phone v. United States, 238 F.2d 266 (D.C. Cir. 1956) was a seminal ruling in United States telecommunications decided by the D.C. Circuit Court of Appeals. Hush-A-Phone Corporation marketed a small, cup-like device which mounted on the speaking party's microphone, reducing the risk of conversations being overheard and increasing sound fidelity for the listening party. At the time, AT&T had a near-monopoly on America's phone system, even controlling the equipment attached to its network. In this era, Americans had to lease equipment from "Ma Bell" or use approved devices. At this time Hush-A-Phone had been around for 20 years without any issues. However, when an AT&T lawyer saw one in a store window, the company decided to sue on the grounds that anything attached to a phone could damage their network.

AT&T, citing the Communications Act of 1934, which stated in part that the company had the right to make changes and dictate "the classifications, practices, and regulations affecting such charges," claimed the right to "forbid attachment to the telephone of any device 'not furnished by the telephone company.'"

Initially, the Federal Communications Commission (FCC) ruled in AT&T's favor. It found that the device was a "foreign attachment" subject to AT&T control and that unrestricted use of the device could, in the commission's opinion, result in a general deterioration of the quality of telephone service.