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πŸ”— 100 prisoners problem

πŸ”— Mathematics

The 100 prisoners problem is a mathematical problem in probability theory and combinatorics. In this problem, 100 numbered prisoners must find their own numbers in one of 100 drawers in order to survive. The rules state that each prisoner may open only 50 drawers and cannot communicate with other prisoners. At first glance, the situation appears hopeless, but a clever strategy offers the prisoners a realistic chance of survival. Danish computer scientist Peter Bro Miltersen first proposed the problem in 2003.

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πŸ”— Naturally-Occurring Nuclear Reactors

πŸ”— Physics πŸ”— Geology

A fossil natural nuclear fission reactor is a uranium deposit where self-sustaining nuclear chain reactions have occurred. This can be examined by analysis of isotope ratios. The conditions under which a natural nuclear reactor could exist had been predicted in 1956 by Paul Kazuo Kuroda. The phenomenon was discovered in 1972 in Oklo, Gabon by French physicist Francis Perrin under conditions very similar to what was predicted.

Oklo is the only known location for this in the world and consists of 16 sites at which self-sustaining nuclear fission reactions are thought to have taken place approximately 1.7 billion years ago, and ran for a few hundred thousand years, averaging probably less than 100 kW of thermal power during that time.

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πŸ”— X32 ABI

πŸ”— Computing πŸ”— Computing/Software πŸ”— Linux

The x32 ABI is an application binary interface (ABI) and one of the interfaces of the Linux kernel. It allows programs to take advantage of the benefits of x86-64 instruction set (larger number of CPU registers, better floating-point performance, faster position-independent code, shared libraries, function parameters passed via registers, faster syscall instruction) while using 32-bit pointers and thus avoiding the overhead of 64-bit pointers.

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πŸ”— Amiga Unix

πŸ”— Computing πŸ”— Computing/Software πŸ”— Computing/Amiga πŸ”— Project-independent assessment

Amiga Unix (informally known as Amix) is a discontinued full port of AT&T Unix System V Release 4 operating system developed by Commodore-Amiga, Inc. in 1990 for the Amiga computer family as an alternative to AmigaOS, which shipped by default. Bundled with the Amiga 3000UX, Commodore's Unix was one of the first ports of SVR4 to the 68k architecture. The Amiga A3000UX model even got the attention of Sun Microsystems, though ultimately nothing came of it.

Unlike Apple's A/UX, Amiga Unix contained no compatibility layer to allow AmigaOS applications to run under Unix. With few native applications available to take advantage of the Amiga's significant multimedia capabilities, it failed to find a niche in the quite-competitive Unix workstation market of the early 1990s. The A3000UX's price tag of $4,998 (equivalent to $9,382 in 2019) was also not very attractive compared to other Unix workstations at the time, such as the NeXTstation ($5,000 for a base system, with a full API and many times the number of applications available), the SGI Indigo (starting at $8,000), or the Personal DECstation 5000 Model 25 (starting at $5,000). Sun, HP, and IBM had similarly priced systems. The A3000UX's 68030 was noticeably underpowered compared to most of its RISC-based competitors.

Unlike typical commercial Unix distributions of the time, Amiga Unix included the source code to the vendor-specific enhancements and platform-dependent device drivers (essentially any part that wasn't owned by AT&T), allowing interested users to study or enhance those parts of the system. However this source code was subject to the same license terms as the binary part of the system – it was not free software. Amiga Unix also incorporated and depended upon many open source components, such as the GNU C Compiler and X Window System, and included their source code.

Like many other proprietary Unix variants with small market shares, Amiga Unix vanished into the mists of computer history when its vendor, Commodore, went out of business. Today, Unix-like operating systems such as Minix, NetBSD, and Linux are available for the Amiga platform.

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πŸ”— Lady Tasting Tea

πŸ”— Mathematics πŸ”— Statistics

In the design of experiments in statistics, the lady tasting tea is a randomized experiment devised by Ronald Fisher and reported in his book The Design of Experiments (1935). The experiment is the original exposition of Fisher's notion of a null hypothesis, which is "never proved or established, but is possibly disproved, in the course of experimentation".

The example is loosely based on an event in Fisher's life. The woman in question, phycologist Muriel Bristol, claimed to be able to tell whether the tea or the milk was added first to a cup. Her future husband, William Roach, suggested that Fisher give her eight cups, four of each variety, in random order. One could then ask what the probability was for her getting the specific number of cups she identified correct (in fact all eight), but just by chance.

Fisher's description is less than 10 pages in length and is notable for its simplicity and completeness regarding terminology, calculations and design of the experiment. The test used was Fisher's exact test.

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πŸ”— Ganjifa

πŸ”— India πŸ”— Board and table games

Ganjifa, Ganjapa or GΓ’njaphΓ’, is a card game and type of playing cards that are most associated with Persia and India. After Ganjifa cards fell out of use in Iran before the twentieth century, India became the last country to produce them. The form prevalent in Odisha is Ganjapa.

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πŸ”— Deseret Alphabet

πŸ”— United States πŸ”— Linguistics πŸ”— Linguistics/Applied Linguistics πŸ”— Writing systems πŸ”— United States/Utah πŸ”— English Language πŸ”— Latter Day Saint movement

The Deseret alphabet ( (listen); Deseret: 𐐔𐐯𐑅𐐨𐑉𐐯𐐻 or 𐐔𐐯𐑆𐐲𐑉𐐯𐐻) is a phonemic English-language spelling reform developed between 1847 and 1854 by the board of regents of the University of Deseret under the leadership of Brigham Young, the second president of the Church of Jesus Christ of Latter-day Saints (LDS Church). George D. Watt is reported to have been the most actively involved in the development of the script,:β€Š159β€Š as well as being its first serious user.:β€Š12β€Š

The Deseret alphabet was an outgrowth of the idealism and utopianism of Young and the early LDS Church. Young and the Mormon pioneers believed "all aspects of life" were in need of reform for the imminent millenniumand the Deseret alphabet was just one of many ways they sought to bring about a complete "transformation in society",:β€Š142β€Š in anticipation of the Second Coming of Jesus. Young wrote of the reform that "it would represent every sound used in the construction of any known language; and, in fact, a step and partial return to a pure language which has been promised unto us in the latter days," the Adamic language spoken before the Tower of Babel.

In public statements, Young claimed the alphabet would replace the traditional Latin alphabet with an alternative, more phonetically accurate alphabet for the English language. This would offer immigrants an opportunity to learn to read and write English, he said, the orthography of which is often less phonetically consistent than those of many other languages.:β€Š65–66β€Š Similar neographies have been attempted, the most well-known of which for English is the Shavian alphabet.

Young also prescribed the learning of Deseret to the school system, stating "It will be the means of introducing uniformity in our orthography, and the years that are now required to learn to read and spell can be devoted to other studies."

During the alphabet's heyday between 1854 and 1869, scriptural passages in newspapers, selected church records, a $5 gold coin, and occasional street signs and correspondence used the new letters. In 1868-9, after much difficulty creating suitable fonts, four books were printed: two school primers, the full Book of Mormon, and a portion of it titled the Book of Nephi.

Despite heavy and costly promotion by the early LDS Church, the alphabet never enjoyed prolonged widespread use and has been regarded by historians as a failure. However, in recent years, aided by digital typography, the Deseret Alphabet has been revived as a cultural heirloom.

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πŸ”— Don't Buy This

πŸ”— Video games

Don't Buy This (also known as Don't Buy This: Five of the Worst Games Ever) is a compilation of video games for the ZX Spectrum released on 1 April 1985. As described on the box, it contains five of the poorest games submitted to publisher Firebird. Instead of rejecting the submissions, they decided to mock the original developers by releasing them together and publicly brand it as "unoriginal" and "awful". Firebird even disowned all their copyright to the game and encouraged buyers to pirate it at will.

Reviews for the game were universally negative, with critics questioning how to critique the game due to its publicity being based on it being a collection of bad games. Despite the negative reception, the game was a commercial success.

πŸ”— Pizza Effect

πŸ”— Religion πŸ”— Sociology

In religious studies and sociology, the pizza effect is the phenomenon of elements of a nation or people's culture being transformed or at least more fully embraced elsewhere, then re-imported back to their culture of origin, or the way in which a community's self-understanding is influenced by (or imposed by, or imported from) foreign sources. It is named after the idea that modern pizza toppings were developed among Italian immigrants in the United States (rather than in native Italy, where in its simpler form it was originally looked down upon), and was later exported back to Italy to be interpreted as a delicacy in Italian cuisine.

Related phrases include "hermeneutical feedback loop", "re-enculturation", and "self-orientalization". The term "pizza effect" was coined by the Austrian-born Hindu monk and professor of Anthropology at Syracuse University, Agehananda Bharati in 1970.

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πŸ”— Extreme Programming

πŸ”— Computing πŸ”— Systems πŸ”— Systems/Software engineering πŸ”— Method engineering

Extreme programming (XP) is a software development methodology intended to improve software quality and responsiveness to changing customer requirements. As a type of agile software development, it advocates frequent releases in short development cycles, intended to improve productivity and introduce checkpoints at which new customer requirements can be adopted.

Other elements of extreme programming include programming in pairs or doing extensive code review, unit testing of all code, not programming features until they are actually needed, a flat management structure, code simplicity and clarity, expecting changes in the customer's requirements as time passes and the problem is better understood, and frequent communication with the customer and among programmers. The methodology takes its name from the idea that the beneficial elements of traditional software engineering practices are taken to "extreme" levels. As an example, code reviews are considered a beneficial practice; taken to the extreme, code can be reviewed continuously (i.e. the practice of pair programming).