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πŸ”— Bloom's 2 sigma problem

πŸ”— Psychology πŸ”— Education

Bloom's 2 sigma problem refers to an educational phenomenon observed by educational psychologist Benjamin Bloom and initially reported in 1984 in the journal Educational Researcher. Bloom found that the average student tutored one-to-one using mastery learning techniques performed two standard deviations better than students who learn via conventional instructional methods β€” that is, "the average tutored student was above 98% of the students in the control class". Additionally, the variation of the students' achievement changed: "about 90% of the tutored students ... attained the level of summative achievement reached by only the highest 20%" of the control class. Bloom's graduate students J. Anania and A. J. Burke conducted studies of this effect at different grade levels and in different schools, observing students with "great differences in cognitive achievement, attitudes, and academic self-concept".

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πŸ”— Homotopy Type Theory

πŸ”— Computer science πŸ”— Mathematics

In mathematical logic and computer science, homotopy type theory (HoTT ) refers to various lines of development of intuitionistic type theory, based on the interpretation of types as objects to which the intuition of (abstract) homotopy theory applies.

This includes, among other lines of work, the construction of homotopical and higher-categorical models for such type theories; the use of type theory as a logic (or internal language) for abstract homotopy theory and higher category theory; the development of mathematics within a type-theoretic foundation (including both previously existing mathematics and new mathematics that homotopical types make possible); and the formalization of each of these in computer proof assistants.

There is a large overlap between the work referred to as homotopy type theory, and as the univalent foundations project. Although neither is precisely delineated, and the terms are sometimes used interchangeably, the choice of usage also sometimes corresponds to differences in viewpoint and emphasis. As such, this article may not represent the views of all researchers in the fields equally. This kind of variability is unavoidable when a field is in rapid flux.

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πŸ”— Germanwings Flight 9525

πŸ”— Aviation πŸ”— France πŸ”— Germany πŸ”— Disaster management πŸ”— Aviation/Aviation accident πŸ”— Spain πŸ”— Crime and Criminal Biography

Germanwings Flight 9525 was a scheduled international passenger flight from Barcelona–El Prat Airport in Spain to DΓΌsseldorf Airport in Germany. The flight was operated by Germanwings, a low-cost carrier owned by the German airline Lufthansa. On 24 March 2015, the aircraft, an Airbus A320-211, crashed 100Β km (62Β mi; 54Β nmi) north-west of Nice in the French Alps. All 144 passengers and six crew members were killed.

The crash was deliberately caused by the co-pilot, Andreas Lubitz, who had previously been treated for suicidal tendencies and declared unfit to work by his doctor. Lubitz kept this information from his employer and instead reported for duty. Shortly after reaching cruise altitude and while the captain was out of the cockpit, Lubitz locked the cockpit door and initiated a controlled descent that continued until the aircraft hit a mountainside.

Aviation authorities swiftly implemented new recommendations from the European Union Aviation Safety Agency that required two authorised personnel in the cockpit at all times but, by 2017, Germanwings and other German airlines had dropped the rule.

The Lubitz family held a press conference in March 2017 during which Lubitz's father said that they did not accept the official investigative findings that his son deliberately caused the crash. By 2017, Lufthansa had paid €75,000 to the family of every victim, as well as €10,000 in pain and suffering compensation to every close relative of a victim.

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πŸ”— MU puzzle

The MU puzzle is a puzzle stated by Douglas Hofstadter and found in GΓΆdel, Escher, Bach involving a simple formal system called "MIU". Hofstadter's motivation is to contrast reasoning within a formal system (ie., deriving theorems) against reasoning about the formal system itself. MIU is an example of a Post canonical system and can be reformulated as a string rewriting system.

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πŸ”— Johns Hopkins Beast

πŸ”— Systems πŸ”— Robotics πŸ”— Systems/Cybernetics

The Johns Hopkins Beast was a mobile automaton, an early pre-robot, built in the 1960s at the Johns Hopkins University Applied Physics Laboratory. The machine had a rudimentary intelligence and the ability to survive on its own. As it wandered through the white halls of the laboratory, it would seek black wall outlets. When it found one it would plug in and recharge.

The robot was cybernetic. It did not use a computer. Its control circuitry consisted of dozens of transistors controlling analog voltages. It used photocell optics and sonar to navigate. The 2N404 transistors were used to create NOR logic gates that implemented the Boolean logic to tell it what to do when a specific sensor was activated. The 2N404 transistors were also used to create timing gates to tell it how long to do something. 2N1040 Power transistors were used to control the power to the motion treads, the boom, and the charging mechanism.

The original sensors in Mod I were physical touch only. The wall socket was detected by physical switches on the arm that followed the wall. Once detected, two electrical prongs were extended until they entered the wall socket and made the electrical connection to charge the vehicle. The stairway, doors, and pipes on the hall wall were also detected by physical switches and recognized by appropriate logic.

The sonar guidance system was developed for Mod I and improved for Mod II. It used two ultrasonic transducers to determine distance, location within the halls, and obstructions in its path. This provided "The Beast" with bat-like guidance. At this point, it could detect obstructions in the hallway, such as people in the hallway. Once an obstruction was detected, the Beast would slow down and then decide whether to stop or divert around the obstruction. It could also ultrasonically recognize the stairway and doorways to take appropriate action.

An optical guidance system was added to Mod II. This provided, among other capabilities, the ability to optically identify the black wall sockets that contrasted with the white wall.

The Hopkins Beast Autonomous Robot Mod II link below was written by Dr. Ronald McConnell, at that time a co-op student and one of the designers for Mod II.

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πŸ”— List of Linux Kernel Names

πŸ”— Lists πŸ”— Linux

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.

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πŸ”— Heilmeier's Catechism: questions for every startup, every project.

πŸ”— Biography πŸ”— Biography/science and academia πŸ”— University of Pennsylvania

George Harry Heilmeier (May 22, 1936 – April 21, 2014) was an American engineer, manager, and a pioneering contributor to liquid crystal displays (LCDs), for which he was inducted into the National Inventors Hall of Fame. Heilmeier's work is an IEEE Milestone.

πŸ”— Sony BMG Rootkit Scandal

πŸ”— Computing πŸ”— Crime πŸ”— Computer Security πŸ”— Computer Security/Computing πŸ”— Business πŸ”— Computing/Software

A scandal erupted in 2005 regarding Sony BMG's implementation of copy protection measures on about 22 million CDs. When inserted into a computer, the CDs installed one of two pieces of software that provided a form of digital rights management (DRM) by modifying the operating system to interfere with CD copying. Neither program could easily be uninstalled, and they created vulnerabilities that were exploited by unrelated malware. One of the programs would install and "phone home" with reports on the user's private listening habits, even if the user refused its end-user license agreement (EULA), while the other was not mentioned in the EULA at all. Both programs contained code from several pieces of copylefted free software in an apparent infringement of copyright, and configured the operating system to hide the software's existence, leading to both programs being classified as rootkits.

Sony BMG initially denied that the rootkits were harmful. It then released an uninstaller for one of the programs that merely made the program's files visible while also installing additional software that could not be easily removed, collected an email address from the user and introduced further security vulnerabilities.

Following public outcry, government investigations and class-action lawsuits in 2005 and 2006, Sony BMG partially addressed the scandal with consumer settlements, a recall of about 10% of the affected CDs and the suspension of CD copy-protection efforts in early 2007.

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πŸ”— Development of Doom

πŸ”— Video games

Doom, a first-person shooter game by id Software, was released in December 1993 and is considered one of the most significant and influential titles in video game history. Development began in November 1992, with programmers John Carmack and John Romero, artists Adrian Carmack and Kevin Cloud, and designer Tom Hall. Late in development, Hall was replaced by Sandy Petersen and programmer Dave Taylor joined. The music and sound effects were created by Bobby Prince.

The Doom concept was proposed in late 1992, after the release of Wolfenstein 3D and its sequel Spear of Destiny. John Carmack was working on an improved 3D game engine from those games, and the team wanted to have their next game take advantage of his designs. Several ideas were proposed, including a new game in their Commander Keen series, but John proposed a game about using technology to fight demons inspired by the Dungeons & Dragons campaigns the team played. The initial months of development were spent building prototypes, while Hall created the Doom Bible, a design document for his vision of the game and its story; after id released a grandiose press release touting features that the team had not yet begun working on, the Doom Bible was rejected in favor of a plotless game with no design document at all.

Over the next six months, Hall designed levels based on real military bases, Romero built features, and artists Adrian and Cloud created textures and demons based on clay models they built. Hall's level designs, however, were deemed uninteresting and Romero began designing his own levels; Hall, increasingly frustrated with his limited influence, was fired in July. He was replaced by Petersen in September, and the team worked increasingly long hours until the game was completed in December 1993. Doom was self-published by id on December 10, 1993, and immediately downloaded by thousands of players.

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πŸ”— 100 Years – The Movie You Will Never See

πŸ”— Film πŸ”— France πŸ”— France/Paris πŸ”— Film/French cinema

100 Years is an upcoming science fiction film written by John Malkovich and directed by Robert Rodriguez. Advertised in 2015 with the tagline "The Movie You Will Never See", it is due to be released on November 18, 2115. The 100 year span matches the time it takes for a bottle of Louis XIII Cognac to be properly aged before its release to consumers. The film stars an international ensemble, with American actor John Malkovich, Taiwanese actress Shuya Chang, and Chilean actor Marko Zaror.

100 Years will apparently be a short film, Rodriguez having stated in a 2019 interview with French YouTuber InThePanda: "I was making several short films for them, and I finished that one first, we shot that one first, I thought that was gonna be a commercial or something. And then I showed them the movie and they said 'Yeah, that's great, that's great. That's the one we lock away.' And I said 'What? That's the one you lock away? What about the other one with the future--' 'No, that's the commercial.' [...] The one that I was most attached to was the one they locked away."

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