Random Articles
Have a deep view into what people are curious about.
π Tokyo's Underground Discharge Channel
The Metropolitan Area Outer Underground Discharge Channel (Japanese: ι¦ι½εε€ιζΎζ°΄θ·―, Hepburn: shutoken gaikaku hΕsuiro), is an underground water infrastructure project in Kasukabe, Saitama, Japan. It is the world's largest underground flood water diversion facility, built to mitigate overflowing of the city's major waterways and rivers during rain and typhoon seasons. It is located between Showa in Tokyo and Kasukabe in Saitama prefecture, on the outskirts of the city of Tokyo in the Greater Tokyo Area, Japan.
Work on the project started in 1992 and was completed by early 2006. It consists of five concrete containment silos with heights of 65 m and diameters of 32 m, connected by 6.4Β km of tunnels, 50 m beneath the surface, as well as a large water tank with a height of 25.4 m, with a length of 177m, with a width of 78m, and with 59 massive pillars connected to 78 10Β MW (13,000Β hp) pumps that can pump up to 200 tons of water into the Edo River per second.
"Ryukyukan" for Underground Exploration Museum of The Metropolitan Area Outer Underground Discharge Channel is also a tourist attraction and can be visited for 3.000 Yen; however, as the tours are conducted in Japanese, a Japanese speaker must be present in the group to act as a translator for non-Japanese speakers.
Discussed on
- "Tokyo's Underground Discharge Channel" | 2019-04-30 | 96 Upvotes 40 Comments
π Gay concentration camps in Chechnya (April 2017)
Anti-gay purges in the Chechen Republic, a part of the Russian Federation, have included forced disappearances β secret abductions, imprisonment, torture β and extrajudicial killing by authorities targeting persons based on their perceived sexual orientation. An unknown number of people, who authorities detained on suspicion of being gay or bisexual, have reportedly died after being held in what human rights groups and eyewitnesses have called concentration camps.
Allegations were initially reported on 1 April 2017 in Novaya Gazeta, a Russian-language opposition newspaper, which reported that since February 2017 over 100 men had allegedly been detained and tortured and at least three had died in an extrajudicial killing. The paper, citing its sources in the Chechen special services, called the wave of detentions a "prophylactic sweep". The journalist who first reported on the subject went into hiding. There have been calls for reprisals against journalists who report on the situation.
As news spread of Chechen authorities' actions, which have been described as part of a systematic anti-LGBT purge, Russian and international activists scrambled to evacuate survivors of the camps and other vulnerable Chechens but were met with difficulty obtaining visas to conduct them safely beyond Russia.
The reports of the persecution were met with a variety of reactions worldwide. The Head of the Chechen Republic Ramzan Kadyrov denied not only the occurrence of any persecution but also the existence of gay men in Chechnya, adding that such people would be killed by their own families. Officials in Moscow were skeptical, although in late May the Russian government reportedly agreed to send an investigative team to Chechnya. Numerous national leaders and other public figures in the West condemned Chechnya's actions, and protests were held in Russia and elsewhere. A report released in December 2018 by the Organization for Security and Cooperation in Europe (OSCE) confirmed claims that persecution of LGBT persons had taken place and was ignored by authorities.
On 11 January 2019, it was reported that another 'gay purge' had begun in the country in December 2018, with several gay men and women being detained. The Russian LGBT Network believes that around 40 persons were detained and two killed.
Discussed on
- "Gay concentration camps in Chechnya (April 2017)" | 2017-04-14 | 40 Upvotes 13 Comments
π Pravetz Computers
Pravetz (ΠΡΠ°Π²Π΅Ρ in the original Cyrillic, series 8 and series 16) were Bulgarian computers, manufactured mainly in the town of Pravetz. Some components and software were produced in Stara Zagora, Plovdiv, and other Bulgarian cities.
Discussed on
- "Pravetz Computers" | 2021-02-11 | 171 Upvotes 50 Comments
π Iran Air Flight 655 (Wikipedia)
Iran Air Flight 655 was a scheduled passenger flight from Tehran to Dubai via Bandar Abbas that was shot down on 3Β July 1988 by an SM-2MR surface-to-air missile fired from USSΒ Vincennes, a guided-missile cruiser of the United States Navy. The aircraft, an Airbus A300, was destroyed and all 290 people on board were killed. The jet was hit while flying over Iran's territorial waters in the Persian Gulf, along the flight's usual route, shortly after departing Bandar Abbas International Airport, the flight's stopover location. The incident occurred during the final stages of the IranβIraq War, which had been continuing for nearly eight years. Vincennes had entered Iranian territory after one of its helicopters drew warning fire from Iranian speedboats operating within Iranian territorial limits.
The reason for the shootdown has been disputed between the governments of the two countries. According to the U.S., the Vincennes crew had incorrectly identified the Airbus as an attacking F-14 Tomcat, a U.S.-made jet fighter that had been part of the Iranian Air Force inventory since the 1970s. While the F-14s had been supplied to Iran in an air-to-air configuration, the Vincennes crew had been briefed that the Iranian F-14s were equipped with air-to-ground ordnance. Vincennes had made ten attempts to contact the aircraft both on military and on civilian frequencies, but had received no response. According to Iran, the cruiser negligently shot down the aircraft, which was transmitting IFF squawks in Mode III, a signal that identified it as a civilian aircraft, and not Mode II as used by Iranian military aircraft. The event generated a great deal of criticism of the United States. Some analysts blamed the captain of Vincennes, William C. Rogers III, for overly aggressive behavior in a tense and dangerous environment. In the days immediately following the incident, President Ronald Reagan issued a written diplomatic note to the Iranian government, expressing deep regret. However, the U.S. continued to insist that Vincennes was acting in self-defense in international waters.
In 1996, the governments of the U.S. and Iran reached a settlement at the International Court of Justice which included the statement "...Β the United States recognized the aerial incident of 3Β July 1988 as a terrible human tragedy and expressed deep regret over the loss of lives caused by the incidentΒ ..." When President Ronald Reagan was directly asked if he considered the statement an apology, Reagan replied, "Yes." As part of the settlement, even though the U.S. government did not admit legal liability or formally apologize to Iran, it still agreed to pay US$61.8 million on an ex gratia basis in compensation to the families of the Iranian victims. The shootdown was the deadliest aviation disaster involving an Airbus A300.
Discussed on
- "Iran Air Flight 655 (Wikipedia)" | 2020-01-08 | 57 Upvotes 24 Comments
π Ahmed Mohamed Clock Incident
On September 14, 2015, 14-year-old Ahmed Mohamed was arrested at MacArthur High School in Irving, Texas, for bringing a disassembled digital clock to school. The incident ignited allegations of racial profiling and Islamophobia from many media sources and commentators.
The episode arose when Mohamed reassembled the parts of a digital clock in an 8-inch (20Β cm) pencil container and brought it to school to show his teachers. His English teacher thought the device resembled a bomb, confiscated it, and reported him to the principal. The local police were called, and they questioned him for an hour and a half. He was handcuffed, taken into custody and transported to a juvenile detention facility, where he was fingerprinted and his mug shot was taken. He was then released to his parents. According to local police, they arrested him because they initially suspected he may have purposely caused a bomb scare. The case was not pursued further by the juvenile justice authorities, but he was suspended from school.
Following the incident, the police determined Mohamed had no malicious intent, and he was not charged with any crime. News of the incident went viralΒ β initially on TwitterΒ β with allegations by commentators that the actions of the school officials and police were due to their stereotyping of Mohamed based on his Sudanese ancestry and Muslim faith. Afterwards, U.S. President Barack Obama as well as other politicians, activists, technology company executives, and media personalities commented about the incident. Many of them praised Mohamed for his ingenuity and creativity, and he was invited to participate in a number of high-profile events related to encouraging youth interest in science and technology. Although Mohamed was cleared in the final police investigation, he became the subject of conspiracy theories β many of them contradictory, citing no evidence, and conflicting with established facts β which claimed that the incident was a deliberate hoax.
On November 23, 2015, Ahmed's family threatened to sue the City of Irving and the school district for civil rights violations and physical and mental anguish unless they received written apologies and compensation of $15 million. This lawsuit was dismissed in May 2017 for lack of evidence. The family also sued conservative talk show hosts Glenn Beck, Ben Shapiro, and another Fox News commentator for lesser amounts on the grounds of defamation of character. Both cases were dismissed with prejudice for First Amendment free speech reasons. In late 2015, his family decided to accept a scholarship from the Qatar Foundation and move to Qatar.
Discussed on
- "Ahmed Mohamed Clock Incident" | 2024-11-24 | 40 Upvotes 46 Comments
π Cryotron
The cryotron is a switch that operates using superconductivity. The cryotron works on the principle that magnetic fields destroy superconductivity. This simple device consists of two superconducting wires (e.g. tantalum and niobium) with different critical temperature (Tc). The cryotron was invented by Dudley Allen Buck of the Massachusetts Institute of Technology Lincoln Laboratory.
As described by Buck, a straight wire of tantalum (having lower Tc) is wrapped around with a wire of niobium in a single layer coil. Both wires are electrically isolated from each other. When this device is immersed in a liquid helium bath both wires become superconducting and hence offer no resistance to the passage of electric current. Tantalum in superconducting state can carry large amount of current as compared to its normal state. Now when current is passed through the niobium coil (wrapped around tantalum) it produces a magnetic field, which in turn reduces (kills) the superconductivity of the tantalum wire and hence reduces the amount of the current that can flow through the tantalum wire. Hence one can control the amount of the current that can flow in the straight wire with the help of small current in the coiled wire. We can think of the tantalum straight wire as a "gate" and the coiled niobium as a "control".
The article by Buck includes descriptions of several logic circuits implemented using cryotrons, including: one stage of a binary adder, carry network, binary accumulator stage, and two stages of a cryotron stepping register.
A planar cryotron using thin films of lead and tin was developed in 1957 by John Bremer at General Electric's General Engineering Lab in Schenectady, New York. This was one of the first integrated circuits, although using superconductors rather than semiconductors. In the next few years, a demonstration computer was made and arrays with 2000 devices operated. A short history of this work is in the November 2007 newsletter of the IEEE History Center.
Juri Matisoo developed a version of the cryotron incorporating a Josephson junction switched by the magnetic field from a control wire. He also explained the shortcomings of traditional cryotrons in which the superconductive material must transition between superconducting and normal states to switch the device, and thus switch relatively slowly. Matisoo's cryotron switched between a conducting state in which 'pair tunneling' of electrons through the gate took place and a 'resistive' state where only single electrons were able to tunnel. The circuit was (like the traditional cryotron) capable of some amplification (i.e gain greater than unity) had a switching rate of less than 800 picoseconds. Although the requirement for cryogenic cooling limited its practicality, it wasn't until the late 2010s that commercial transistors came close to matching this performance.
There have been periods of renewed interest in various types of cryotron, IBM experimented with using them for limited applications in supercomputers during the 1980s and (as of 2020) there has been some investigation of their potential applications both to I/O and logic in prototype quantum computers.
π The Awful German Language
"The Awful German Language" is an 1880 essay by Mark Twain published as Appendix D in A Tramp Abroad. The essay is a humorous exploration of the frustrations a native speaker of English has with learning German as a second language.
Discussed on
- "The Awful German Language" | 2021-05-16 | 46 Upvotes 52 Comments
π Tommy Flowers
Thomas Harold Flowers MBE (22 December 1905 - 28 October 1998) was an English engineer with the British General Post Office. During World War II, Flowers designed and built Colossus, the world's first programmable electronic computer, to help decipher encrypted German messages.
π List of Linux Kernel Names
Most of the Linux 1.2 and above kernels include a name in the Makefile of their source trees, which can be found in the git repository.
Discussed on
- "List of Linux kernel names" | 2011-10-24 | 62 Upvotes 11 Comments
π British Expedition to Abyssinia
The British Expedition to Abyssinia was a rescue mission and punitive expedition carried out in 1868 by the armed forces of the British Empire against the Ethiopian Empire. Emperor Tewodros II of Ethiopia, then often referred to by the anglicized name Theodore, imprisoned several missionaries and two representatives of the British government in an attempt to get the attention of the British government, which had decided against his requests for military assistance. The punitive expedition launched by the British in response required the transportation of a sizable military force hundreds of miles across mountainous terrain lacking any road system. The formidable obstacles to the action were overcome by the commander of the expedition, General Sir Robert Napier, who was victorious in every battle with the troops of Tewodros, captured the Ethiopian capital and rescued all the hostages. The expedition was widely hailed on its return for achieving all its objectives.
Harold G. Marcus described the action as "one of the most expensive affairs of honour in history."
Discussed on
- "British Expedition to Abyssinia" | 2019-08-06 | 60 Upvotes 24 Comments