Random Articles (Page 359)

Have a deep view into what people are curious about.

🔗 NATO Bombing of Yugoslavia

🔗 Serbia 🔗 Yugoslavia 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/French military history 🔗 Military history/Balkan military history 🔗 Military history/European military history 🔗 Military history/Post-Cold War 🔗 Kosovo 🔗 NATO 🔗 Serbia/Belgrade

The North Atlantic Treaty Organisation (NATO) carried out an aerial bombing campaign against the Federal Republic of Yugoslavia during the Kosovo War. The air strikes lasted from 24 March 1999 to 10 June 1999. The bombings continued until an agreement was reached that led to the withdrawal of Yugoslav armed forces from Kosovo, and the establishment of the United Nations Interim Administration Mission in Kosovo, a UN peacekeeping mission in Kosovo. The official NATO operation code name was Operation Allied Force whereas the United States called it Operation Noble Anvil; in Yugoslavia the operation was incorrectly called Merciful Angel (Serbian: Милосрдни анђео / Milosrdni anđeo) as a result of a misunderstanding or mistranslation.

NATO's intervention was prompted by Yugoslavia's bloodshed and ethnic cleansing of Albanians, which drove the Albanians into neighbouring countries and had the potential to destabilize the region. Yugoslavia's actions had already provoked condemnation by international organisations and agencies such as the UN, NATO, and various INGOs. Yugoslavia's refusal to sign the Rambouillet Accords was initially offered as justification for NATO's use of force. NATO countries attempted to gain authorisation from the UN Security Council for military action, but were opposed by China and Russia, who indicated that they would veto such a measure. As a result, NATO launched its campaign without the UN's approval, stating that it was a humanitarian intervention. The UN Charter prohibits the use of force except in the case of a decision by the Security Council under Chapter VII, or self-defence against an armed attack – neither of which were present in this case.

By the end of the war, the Yugoslavs had killed 1,500 to 2,131 combatants, while choosing to heavily target Kosovar Albanian civilians, with 8,676 killed or missing and some 848,000 expelled from Kosovo. The NATO bombing killed about 1,000 members of the Yugoslav security forces in addition to between 489 and 528 civilians. It destroyed or damaged bridges, industrial plants, hospitals, schools, cultural monuments, private businesses as well as barracks and military installations. In the days after the Yugoslav army withdrew, over 164,000 Serbs and 24,000 Roma left Kosovo. Many of the remaining non-Albanian civilians (as well as Albanians perceived as collaborators) were victims of abuse which included beatings, abductions, and murders. After Kosovo and other Yugoslav Wars, Serbia became home to the highest number of refugees and IDPs (including Kosovo Serbs) in Europe.

The bombing was NATO's second major combat operation, following the 1995 bombing campaign in Bosnia and Herzegovina. It was the first time that NATO had used military force without the expressed endorsement of the UN Security Council, which triggered debates over the legitimacy of the intervention.

Discussed on

🔗 Secretary Problem

🔗 Mathematics 🔗 Statistics

The secretary problem is a problem that demonstrates a scenario involving optimal stopping theory. The problem has been studied extensively in the fields of applied probability, statistics, and decision theory. It is also known as the marriage problem, the sultan's dowry problem, the fussy suitor problem, the googol game, and the best choice problem.

The basic form of the problem is the following: imagine an administrator who wants to hire the best secretary out of n {\displaystyle n} rankable applicants for a position. The applicants are interviewed one by one in random order. A decision about each particular applicant is to be made immediately after the interview. Once rejected, an applicant cannot be recalled. During the interview, the administrator gains information sufficient to rank the applicant among all applicants interviewed so far, but is unaware of the quality of yet unseen applicants. The question is about the optimal strategy (stopping rule) to maximize the probability of selecting the best applicant. If the decision can be deferred to the end, this can be solved by the simple maximum selection algorithm of tracking the running maximum (and who achieved it), and selecting the overall maximum at the end. The difficulty is that the decision must be made immediately.

The shortest rigorous proof known so far is provided by the odds algorithm (Bruss 2000). It implies that the optimal win probability is always at least 1 / e {\displaystyle 1/e} (where e is the base of the natural logarithm), and that the latter holds even in a much greater generality (2003). The optimal stopping rule prescribes always rejecting the first n / e {\displaystyle \sim n/e} applicants that are interviewed and then stopping at the first applicant who is better than every applicant interviewed so far (or continuing to the last applicant if this never occurs). Sometimes this strategy is called the 1 / e {\displaystyle 1/e} stopping rule, because the probability of stopping at the best applicant with this strategy is about 1 / e {\displaystyle 1/e} already for moderate values of n {\displaystyle n} . One reason why the secretary problem has received so much attention is that the optimal policy for the problem (the stopping rule) is simple and selects the single best candidate about 37% of the time, irrespective of whether there are 100 or 100 million applicants.

Discussed on

🔗 Hachikō

🔗 Dogs 🔗 Japan 🔗 Public Art 🔗 Japan/History

Hachikō (ハチ公, November 10, 1923 – March 8, 1935) was a Japanese Akita dog remembered for his remarkable loyalty to his owner, Hidesaburō Ueno, for whom he continued to wait for over nine years following Ueno's death.

Hachikō was born on November 10, 1923, at a farm near the city of Ōdate, Akita Prefecture. In 1924, Hidesaburō Ueno, a professor at the Tokyo Imperial University, brought him to live in Shibuya, Tokyo, as his pet. Hachikō would meet Ueno at Shibuya Station every day after his commute home. This continued until May 21, 1925, when Ueno died of a cerebral hemorrhage while at work. From then until his death on March 8, 1935, Hachikō would return to Shibuya Station every day to await Ueno's return.

During his lifetime, the dog was held up in Japanese culture as an example of loyalty and fidelity. Well after his death, he continues to be remembered in worldwide popular culture, with statues, movies, books, and appearances in various media. Hachikō is known in Japanese as chūken Hachikō (忠犬ハチ公) "faithful dog Hachikō", hachi meaning "eight" and the suffix -kō indicating affection.

Discussed on

🔗 WWII: Failed novelist becomes a spy for Germany, makes up a fake spy network

🔗 Biography 🔗 Espionage 🔗 Military history 🔗 Military history/Military biography 🔗 Biography/military biography 🔗 Military history/Intelligence 🔗 United Kingdom 🔗 Military history/World War II 🔗 Military history/German military history 🔗 Military history/Spanish military history 🔗 Spain 🔗 Military history/European military history 🔗 Military history/British military history

Juan Pujol García (Spanish: [ˈxwan puˈʝol ɣaɾˈθi.a]; 14 February 1912 – 10 October 1988), also known as Joan Pujol i García (Catalan: [ʒuˈan puˈʒɔl i ɣəɾˈsi.ə]), was a Spanish spy who acted as a double agent loyal to Great Britain against Nazi Germany during World War II, when he relocated to Britain to carry out fictitious spying activities for the Germans. He was given the codename Garbo by the British; their German counterparts codenamed him Alaric and referred to his non-existent spy network as "Arabal".

After developing a loathing of political extremism of all sorts during the Spanish Civil War, Pujol decided to become a spy for Britain as a way to do something "for the good of humanity". Pujol and his wife contacted the British Embassy in Madrid, which rejected his offer.

Undeterred, he created a false identity as a fanatically pro-Nazi Spanish government official and successfully became a German agent. He was instructed to travel to Britain and recruit additional agents; instead he moved to Lisbon and created bogus reports about Britain from a variety of public sources, including a tourist guide to Britain, train timetables, cinema newsreels and magazine advertisements.

Although the information would not have withstood close examination, Pujol soon established himself as a trustworthy agent. He began inventing fictitious sub-agents who could be blamed for false information and mistakes. The Allies finally accepted Pujol when the Germans expended considerable resources attempting to hunt down a fictitious convoy. Following interviews by Desmond Bristow of Section V MI6 Iberian Section, Juan Pujol was taken on. The family were moved to Britain and Pujol was given the code name "Garbo". Pujol and his handler Tomás Harris spent the rest of the war expanding the fictitious network, communicating to the German handlers at first by letters and later by radio. Eventually the Germans were funding a network of 27 agents, all fictitious.

Pujol had a key role in the success of Operation Fortitude, the deception operation intended to mislead the Germans about the timing, location and scale of the invasion of Normandy in 1944. The false information Pujol supplied helped persuade the Germans that the main attack would be in the Pas de Calais, so that they kept large forces there before and even after the invasion. Pujol had the distinction of receiving military decorations from both sides of the war – being awarded the Iron Cross and becoming a Member of the Order of the British Empire.

🔗 Archimedes Palimpsest

🔗 History 🔗 Mathematics 🔗 Books 🔗 Greece 🔗 History of Science

The Archimedes Palimpsest is a parchment codex palimpsest, originally a Byzantine Greek copy of a compilation of Archimedes and other authors. It contains two works of Archimedes that were thought to have been lost (the Ostomachion and the Method of Mechanical Theorems) and the only surviving original Greek edition of his work On Floating Bodies. The first version of the compilation is believed to have been produced by Isidorus of Miletus, the architect of the geometrically complex Hagia Sophia cathedral in Constantinople, sometime around AD 530. The copy found in the palimpsest was created from this original, also in Constantinople, during the Macedonian Renaissance (c. AD 950), a time when mathematics in the capital was being revived by the former Greek Orthodox bishop of Thessaloniki Leo the Geometer, a cousin of the Patriarch.

Following the sack of Constantinople by Western crusaders in 1204, the manuscript was taken to an isolated Greek monastery in Palestine, possibly to protect it from occupying crusaders, who often equated Greek script with heresy against their Latin church and either burned or looted many such texts (including at least two other copies of Archimedes). The complex manuscript was not appreciated at this remote monastery and was soon overwritten (1229) with a religious text. In 1899, nine hundred years after it was written, the manuscript was still in the possession of the Greek church, and back in Istanbul, where it was catalogued by the Greek scholar Papadopoulos-Kerameus, attracting the attention of Johan Heiberg. Heiberg visited the church library and was allowed to make detailed photographs in 1906. Most of the original text was still visible, and Heiberg published it in 1915. In 1922 the manuscript went missing in the midst of the evacuation of the Greek Orthodox library in Istanbul, during a tumultuous period following the World War I. Concealed for over 70 years by a Western businessman, forged pictures were painted on top of some text to increase resale value. Unable to sell the book privately, in 1998 the businessman's daughter risked a public auction in New York contested by the Greek church; the U.S. court ruled for the auction, and the manuscript was purchased by an anonymous buyer (rumored to be Jeff Bezos). The texts under the forged pictures, and previously unreadable texts, were revealed by analyzing images produced by ultraviolet, infrared, visible and raking light, and X-ray.

All images and transcriptions are now freely available on the web at the Archimedes Digital Palimpsest under the Creative Commons License CC BY.

Discussed on

🔗 Organ harvesting from Falun Gong practitioners in China

🔗 Human rights 🔗 Medicine 🔗 Religion 🔗 Death 🔗 China 🔗 Religion/New religious movements 🔗 Religion/Falun Gong

Reports of forced organ harvesting from Falun Gong practitioners and other political prisoners in China have raised increasing concern within the international community. According to a report by former lawmaker David Kilgour, human rights campaigner David Matas and Victims of Communism Memorial Foundation researcher Ethan Gutmann, political prisoners, mainly Falun Gong practitioners, may be executed "on demand" in order to provide organs for transplant to recipients.

Reports on systematic organ harvesting from Falun Gong prisoners first emerged in 2006, though the practice is thought by some to have started six years earlier. Several researchers—most notably Matas, Kilgour and Gutmann—estimate that tens of thousands of Falun Gong prisoners of conscience have been killed to supply a lucrative trade in human organs and cadavers and that these abuses may be ongoing. These conclusions are based on a combination of statistical analysis; interviews with former prisoners, medical authorities and public security agents; and circumstantial evidence, such as the large number of Falun Gong practitioners detained extrajudicially in China and the profits to be made from selling organs.

The Chinese government long denied all accusations of organ harvesting. However, the failure of Chinese authorities to effectively address or refute the charges has drawn attention and public condemnation from some governments, international organizations and medical societies. The parliaments of Canada and the European Union, as well as the U.S. Senate and House of Representatives, have adopted resolutions condemning the forced organ harvesting from Falun Gong prisoners of conscience. United Nations Special Rapporteurs have called on the Chinese government to account for the sources of organs used in transplant practices, and the World Medical Association, the American Society of Transplantation and the Transplantation Society have called for sanctions on Chinese medical authorities. Several countries have also taken or considered measures to deter their citizens from travelling to China for the purpose of obtaining organs. A documentary on organ harvesting from Falun Gong practitioners, Human Harvest, received a 2014 Peabody Award recognizing excellence in broadcast journalism. China eventually admitted that it had engaged in systematic organ harvesting from death row prisoners, though it denies that such an organ harvesting program is ongoing.

🔗 Starlite

🔗 Brands 🔗 Chemistry 🔗 Invention 🔗 Polymers

Starlite is an intumescent material claimed to be able to withstand and insulate from extreme heat. It was invented by British amateur chemist and hairdresser Maurice Ward (1933-2011) during the 1970s and 1980s, and received significant publicity after coverage of the material aired in 1990 on the BBC science and technology show Tomorrow's World. The name Starlite was coined by Ward's granddaughter Kimberly.

The American company Thermashield, LLC claims to have acquired the rights to Starlite in 2013 and replicated it. It is the only company to have itself publicly demonstrated the technology and have samples tested by third parties.

Discussed on

🔗 Floyd-Steinberg Dithering Algorithm

🔗 Computer science

Floyd–Steinberg dithering is an image dithering algorithm first published in 1976 by Robert W. Floyd and Louis Steinberg. It is commonly used by image manipulation software, for example when an image is converted into GIF format that is restricted to a maximum of 256 colors.

The algorithm achieves dithering using error diffusion, meaning it pushes (adds) the residual quantization error of a pixel onto its neighboring pixels, to be dealt with later. It spreads the debt out according to the distribution (shown as a map of the neighboring pixels):

[ 7 16 3 16 5 16 1 16 ] {\displaystyle {\begin{bmatrix}&&*&{\frac {\displaystyle 7}{\displaystyle 16}}&\ldots \\\ldots &{\frac {\displaystyle 3}{\displaystyle 16}}&{\frac {\displaystyle 5}{\displaystyle 16}}&{\frac {\displaystyle 1}{\displaystyle 16}}&\ldots \\\end{bmatrix}}}

The pixel indicated with a star (*) indicates the pixel currently being scanned, and the blank pixels are the previously-scanned pixels. The algorithm scans the image from left to right, top to bottom, quantizing pixel values one by one. Each time the quantization error is transferred to the neighboring pixels, while not affecting the pixels that already have been quantized. Hence, if a number of pixels have been rounded downwards, it becomes more likely that the next pixel is rounded upwards, such that on average, the quantization error is close to zero.

The diffusion coefficients have the property that if the original pixel values are exactly halfway in between the nearest available colors, the dithered result is a checkerboard pattern. For example, 50% grey data could be dithered as a black-and-white checkerboard pattern. For optimal dithering, the counting of quantization errors should be in sufficient accuracy to prevent rounding errors from affecting the result.

In some implementations, the horizontal direction of scan alternates between lines; this is called "serpentine scanning" or boustrophedon transform dithering.

In the following pseudocode we can see the algorithm described above. This works for any approximately linear encoding of pixel values, such as 8-bit integers, 16-bit integers or real numbers in the range [0,1].

for each y from top to bottom do
    for each x from left to right do
        oldpixel := pixel[x][y]
        newpixel := find_closest_palette_color(oldpixel)
        pixel[x][y] := newpixel
        quant_error := oldpixel - newpixel
        pixel[x + 1][y    ] := pixel[x + 1][y    ] + quant_error × 7 / 16
        pixel[x - 1][y + 1] := pixel[x - 1][y + 1] + quant_error × 3 / 16
        pixel[x    ][y + 1] := pixel[x    ][y + 1] + quant_error × 5 / 16
        pixel[x + 1][y + 1] := pixel[x + 1][y + 1] + quant_error × 1 / 16

When converting 16 bit greyscale to 8 bit, find_closest_palette_color() may perform just a simple rounding, for example:

find_closest_palette_color(oldpixel) = round(oldpixel / 256)

The pseudocode can result in pixel values exceeding the valid values (such as greater than 1 in a [0,1] representation). Such values should ideally be clipped by the find_closest_palette_color() function, rather than clipping the intermediate values, since a subsequent error may bring the value back into range. However, if fixed-width integers are used, wrapping of intermediate values would cause inversion of black and white, and so should be avoided.

Discussed on

🔗 Maria Montessori

🔗 Biography 🔗 Philosophy 🔗 Psychology 🔗 Philosophy/Social and political philosophy 🔗 Biography/science and academia 🔗 Women's History 🔗 Philosophy/Contemporary philosophy 🔗 Philosophy/Philosophers 🔗 Education 🔗 Women in Business

Maria Tecla Artemisia Montessori ( MON-tiss-OR-ee, Italian: [maˈriːa montesˈsɔːri]; August 31, 1870 – May 6, 1952) was an Italian physician and educator best known for the philosophy of education that bears her name, and her writing on scientific pedagogy. At an early age, Montessori broke gender barriers and expectations when she enrolled in classes at an all-boys technical school, with hopes of becoming an engineer. She soon had a change of heart and began medical school at the Sapienza University of Rome, where she graduated – with honors – in 1896. Her educational method is in use today in many public and private schools globally.

Discussed on

🔗 Differential Power Analysis

🔗 Cryptography 🔗 Cryptography/Computer science

In cryptography, power analysis is a form of side channel attack in which the attacker studies the power consumption of a cryptographic hardware device (such as a smart card, tamper-resistant "black box", or integrated circuit). The attack can non-invasively extract cryptographic keys and other secret information from the device.

Simple power analysis (SPA) involves visually interpreting power traces, or graphs of electrical activity over time. Differential power analysis (DPA) is a more advanced form of power analysis, which can allow an attacker to compute the intermediate values within cryptographic computations through statistical analysis of data collected from multiple cryptographic operations. SPA and DPA were introduced to the open cryptology community in 1998 by Paul Kocher, Joshua Jaffe and Benjamin Jun.