Have a deep view into what people are curious about.

🔗 Biography 🔗 France 🔗 Philosophy 🔗 Biography/science and academia 🔗 Philosophy/Philosophers 🔗 Philosophy/Epistemology 🔗 Philosophy/Modern philosophy 🔗 Libertarianism

Michel Eyquem, Seigneur de Montaigne ( mon-TAYN; French: [miʃɛl ekɛm də mɔ̃tɛɲ]; 28 February 1533 – 13 September 1592), known as Michel de Montaigne, was one of the most significant philosophers of the French Renaissance. He is known for popularizing the essay as a literary genre. His work is noted for its merging of casual anecdotes and autobiography with intellectual insight. Montaigne had a direct influence on numerous Western writers; his massive volume Essais contains some of the most influential essays ever written.

During his lifetime, Montaigne was admired more as a statesman than as an author. The tendency in his essays to digress into anecdotes and personal ruminations was seen as detrimental to proper style rather than as an innovation, and his declaration that "I am myself the matter of my book" was viewed by his contemporaries as self-indulgent. In time, however, Montaigne came to be recognized as embodying, perhaps better than any other author of his time, the spirit of freely entertaining doubt that began to emerge at that time. He is most famously known for his skeptical remark, ''Que sçay-je?" ("What do I know?", in Middle French; now rendered as "Que sais-je?" in modern French).

🔗 Computing 🔗 Systems 🔗 Engineering 🔗 Systems/Systems engineering

The purpose of a system is what it does (POSIWID) is a systems thinking heuristic coined by Stafford Beer, who observed that there is "no point in claiming that the purpose of a system is to do what it constantly fails to do." The term is widely used by systems theorists, and is generally invoked to counter the notion that the purpose of a system can be read from the intentions of those who design, operate, or promote it. When a system's side effects or unintended consequences reveal that its behavior is poorly understood, then the POSIWID perspective can balance political understandings of system behavior with a more straightforwardly descriptive view.

🔗 Physics 🔗 Geology 🔗 Physics/Acoustics

Singing sand, also called whistling sand, barking sand or singing dune, is sand that produces sound. The sound emission may be caused by wind passing over dunes or by walking on the sand.

Certain conditions have to come together to create singing sand:

1. The sand grains have to be round and between 0.1 and 0.5 mm in diameter.
2. The sand has to contain silica.
3. The sand needs to be at a certain humidity.

The most common frequency emitted seems to be close to 450 Hz.

There are various theories about the singing sand mechanism. It has been proposed that the sound frequency is controlled by the shear rate. Others have suggested that the frequency of vibration is related to the thickness of the dry surface layer of sand. The sound waves bounce back and forth between the surface of the dune and the surface of the moist layer, creating a resonance that increases the sound's volume. The noise may be generated by friction between the grains or by the compression of air between them.

Other sounds that can be emitted by sand have been described as "roaring" or "booming".

🔗 Computing 🔗 Computer Security 🔗 Computer Security/Computing

A zip bomb, also known as a zip of death or decompression bomb, is a malicious archive file designed to crash or render useless the program or system reading it. It is often employed to disable antivirus software, in order to create an opening for more traditional viruses.

Rather than hijacking the normal operation of the program, a zip bomb allows the program to work as intended, but the archive is carefully crafted so that unpacking it (e.g. by a virus scanner in order to scan for viruses) requires inordinate amounts of time, disk space or memory.

Most modern antivirus programs can detect whether a file is a zip bomb, to avoid unpacking it.

🔗 Chemicals

Fluoroantimonic acid is a mixture of hydrogen fluoride and antimony pentafluoride, containing various cations and anions (the simplest being H
₂F⁺
and SbF⁻
₆). This substance is a superacid that can be excess of a quadrillion times stronger than 100% pure sulfuric acid, depending on proportion of its ingredients. It has been shown to protonate even hydrocarbons to afford pentacoordinate carbocations (carbonium ions). Extreme caution needs to be in place when handling fluoroantimonic acid. It is exceptionally corrosive, but can be stored in containers lined with PTFE (Teflon).

🔗 Business

The bullwhip effect is a supply chain phenomenon where orders to suppliers tend to have a larger variability than sales to buyers, which results in an amplified demand variability upstream. In part, this results in increasing swings in inventory in response to shifts in consumer demand as one moves further up the supply chain. The concept first appeared in Jay Forrester's Industrial Dynamics (1961) and thus it is also known as the Forrester effect. It has been described as "the observed propensity for material orders to be more variable than demand signals and for this variability to increase the further upstream a company is in a supply chain".

Research at Stanford University helped incorporate the concept into supply chain vernacular using a story about Volvo. Suffering a glut in green cars, sales and marketing developed a program to sell the excess inventory. While successful in generating the desired market pull, manufacturing did not know about the promotional plans. Instead, they read the increase in sales as an indication of growing demand for green cars and ramped up production.

Research indicates a fluctuation in point-of-sale demand of five percent will be interpreted by supply chain participants as a change in demand of up to forty percent. Much like cracking a whip, a small flick of the wrist - a shift in point of sale demand - can cause a large motion at the end of the whip - manufacturers' responses.

🔗 Mass surveillance 🔗 Law

Wikimedia Foundation, et al. v. National Security Agency, et al. is a lawsuit filed by the American Civil Liberties Union (ACLU) on behalf of the Wikimedia Foundation and several other organizations against the National Security Agency (NSA), the United States Department of Justice (DOJ), and other named individuals, alleging mass surveillance of Wikipedia users carried out by the NSA. The suit claims the surveillance system, which NSA calls "Upstream", breaches the First Amendment to the United States Constitution, which protects freedom of speech, and the Fourth Amendment to the United States Constitution, which prohibits unreasonable searches and seizures.

The suit was filed in the United States District Court for the District of Maryland as the NSA is based in Fort Meade, Maryland. The suit was dismissed in October 2015 by Judge T. S. Ellis III; this decision was appealed four months later to the Fourth Circuit Court of Appeals by the Wikimedia Foundation. The Court of Appeals found that the dismissal was valid for all of the plaintiffs except the Foundation, whose allegations the court found "plausible" enough to have legal standing for the case to be remanded to the lower court.

The original plaintiffs besides the Wikimedia Foundation were the National Association of Criminal Defense Lawyers, Human Rights Watch, Amnesty International USA, the PEN American Center, the Global Fund for Women, The Nation magazine, the Rutherford Institute, and the Washington Office on Latin America.

🔗 Biography 🔗 Philosophy 🔗 Politics 🔗 Philosophy/Social and political philosophy 🔗 Biography/science and academia 🔗 Philosophy/Philosophers 🔗 India 🔗 Philosophy/Ancient philosophy 🔗 India/Bihar 🔗 Philosophy/Eastern philosophy 🔗 Hinduism 🔗 India/Indian history workgroup 🔗 India/Patna

Chanakya (IAST: Cāṇakya, pronunciation ) was an ancient Indian teacher, philosopher, economist, jurist and royal advisor. He is traditionally identified as Kauṭilya or Vishnugupta, who authored the ancient Indian political treatise, the Arthashastra, a text dated to roughly between the 3rd century BCE and the 3rd century CE. As such, he is considered the pioneer of the field of political science and economics in India, and his work is thought of as an important precursor to classical economics. His works were lost near the end of the Gupta Empire in the 6th century CE and not rediscovered until the early 20th century.

Chanakya assisted the first Mauryan emperor Chandragupta in his rise to power. He is widely credited for having played an important role in the establishment of the Maurya Empire. Chanakya served as the chief advisor to both emperors Chandragupta and his son Bindusara.

🔗 Biography 🔗 Russia 🔗 Statistics 🔗 Biography/science and academia 🔗 Russia/science and education in Russia

Alexey Yakovlevich Chervonenkis (Russian: Алексей Яковлевич Червоненкис; 7 September 1938 – 22 September 2014) was a Soviet and Russian mathematician, and, with Vladimir Vapnik, was one of the main developers of the Vapnik–Chervonenkis theory, also known as the "fundamental theory of learning" an important part of computational learning theory. Chervonenkis held joint appointments with the Russian Academy of Sciences and Royal Holloway, University of London.

Alexey Chervonenkis got lost in Losiny Ostrov National Park on 22 September 2014, and later during a search operation was found dead near Mytishchi, a suburb of Moscow. He had died of hypothermia.

🔗 Time

The Pax calendar was invented by James A. Colligan, SJ in 1930 as a perennializing reform of the annualized Gregorian calendar.