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πŸ”— Charlieplexing

πŸ”— Computing πŸ”— Electronics πŸ”— Electrical engineering

Charlieplexing (also known as tristate multiplexing, reduced pin-count LED multiplexing, complementary LED drive and crossplexing) is a technique for accessing a large number of LEDs, switches, micro-capacitors or other I/O entities, using very few tri-state logic wires from a microcontroller, these entities being wired as discrete components, x/y arrays, or woven in a diagonally intersecting pattern to form diagonal arrays.

The method uses the tri-state logic capabilities of microcontrollers in order to gain efficiency over traditional multiplexing, each I/O pin being capable, when required, of rapidly changing between the three states, logical 1, logical 0, and high impedance.

This enables these I/O entities (LEDs, switches etc.) to be connected between any two microcontroller I/Os - e.g. with 4 I/Os, each I/O can pair with 3 other I/Os, resulting in 6 unique pairings (1/2, 1/3, 1/4, 2/3, 2/4, 3/4). Only 4 pairings are possible with standard x/y multiplexing (1/3, 1/4, 2/3, 2/4). Also, due to the microcontroller's ability to reverse the polarity of the 6 I/O pairs, the number of LEDS (or diodes) that are uniquely addressable, can be doubled to 12 - adding LEDS 2/1, 3/1, 4/1, 3/2, 4/2 and 4/3.

Although it is more efficient in its use of I/O, a small amount of address manipulation is required when trying to fit Charlieplexing into a standard x/y array.

Other issues that affect standard multiplexing but are exacerbated by Charlieplexing are:

  • consideration of current requirements and the forward voltages of the LEDs.
  • a requirement to cycle through the in-use LEDs rapidly so that the persistence of the human eye perceives the display to be lit as a whole. Multiplexing can generally be seen by a strobing effect and skewing if the eye's focal point is moved past the display rapidly.


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πŸ”— Processed Pizza Cheeses

πŸ”— Food and drink πŸ”— Guild of Copy Editors πŸ”— Food and drink/Cheeses

Pizza cheese encompasses several varieties and types of cheeses and dairy products that are designed and manufactured for use specifically on pizza. These include processed and modified cheese such as mozzarella-like processed cheeses and mozzarella variants. The term can also refer to any type of cheese suitable for use on pizza. The most popular cheeses used in the preparation of pizza are mozzarella (accounting for about 30%), provolone, cheddar and Parmesan. Emmental, Romano and ricotta are often used as toppings, and processed pizza cheeses manufactured specifically for pizza are mass-produced. Some mass-produced pizza cheeses are frozen after manufacturing and shipped frozen.

Processed pizza cheese is manufactured to produce optimal qualities in browning, melting, stretchiness and fat and moisture content. Several studies and experiments have analyzed the impact of vegetable oil, manufacturing and culture processes, denatured whey proteins and other changes to create ideal and economical pizza cheeses. In 1997, it was estimated that annual production of pizza cheese products was 2 billion pounds in the United States and 200 million pounds in Europe, and in 2000 demand for the product in Europe was increasing by 8% per year. The trend of steadily-increasing production and consumption of mozzarella and pizza cheese continued into the first decade of the 21st century in the United States.

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πŸ”— Lunar Lava Tube

πŸ”— Volcanoes πŸ”— Astronomy πŸ”— Solar System πŸ”— Solar System/Moon

Lunar lava tubes are lava tubes on the Moon formed during the eruption of basaltic lava flows. When the surface of a lava flow cools, it hardens and the lava can channel beneath the surface in a tube-shaped passage. Once the flow of lava diminishes, the tube may drain, forming a hollow void. Lunar lava tubes are formed on sloped surfaces that range in angle from 0.4Β° to 6.5Β°. These tubes may be as wide as 500 metres (1,600Β ft) before they become unstable against gravitational collapse. However, stable tubes may still be disrupted by seismic events or meteoroid bombardment.

The existence of a lava tube is sometimes revealed by the presence of a "skylight", a place in which the roof of the tube has collapsed, leaving a circular hole that can be observed by lunar orbiters.

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πŸ”— Iannis Xenakis - Wikipedia, the free encyclopedia

πŸ”— Biography πŸ”— Military history πŸ”— Architecture πŸ”— Greece πŸ”— Military history/Military biography πŸ”— Biography/military biography πŸ”— Military history/World War II πŸ”— Military history/Cold War πŸ”— Dance πŸ”— Composers πŸ”— Dance/Ballet πŸ”— Classical music πŸ”— Military history/Balkan military history πŸ”— Biography/Musicians πŸ”— Military history/European military history

Iannis Xenakis (also spelt as Yannis Xenakis) (Greek: Γιάννης (Ιάννης) ΞžΞ΅Ξ½Ξ¬ΞΊΞ·Ο‚ [ˈʝanis kseˈnacis]; 29 May 1922 – 4 February 2001) was a Greek-French composer, music theorist, architect, performance director and engineer. After 1947, he fled Greece, becoming a naturalized citizen of France. He is considered an important post-World War II composer whose works helped revolutionize 20th-century classical music.

Xenakis pioneered the use of mathematical models in music such as applications of set theory, stochastic processes and game theory and was also an important influence on the development of electronic and computer music. He integrated music with architecture, designing music for pre-existing spaces, and designing spaces to be integrated with specific music compositions and performances.

Among his most important works are Metastaseis (1953–54) for orchestra, which introduced independent parts for every musician of the orchestra; percussion works such as Psappha (1975) and Pléïades (1979); compositions that introduced spatialization by dispersing musicians among the audience, such as Terretektorh (1966); electronic works created using Xenakis's UPIC system; and the massive multimedia performances Xenakis called polytopes, that were a summa of his interests and skills. Among the numerous theoretical writings he authored, the book Formalized Music: Thought and Mathematics in Composition (French edition 1963, English translation 1971) is regarded as one of his most important. As an architect, Xenakis is primarily known for his early work under Le Corbusier: the Sainte Marie de La Tourette, on which the two architects collaborated, and the Philips Pavilion at Expo 58, which Xenakis designed by himself.

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πŸ”— Hokkaido characters

πŸ”— Writing systems πŸ”— Japan πŸ”— Japan/History πŸ”— Japan/Ainu

The Hokkaido characters (εŒ—ζ΅·ι“η•°δ½“ζ–‡ε­—, hokkaidō itai moji), also known as Aino characters (γ‚’γ‚€γƒŽγƒ’γ‚Έ, aino moji) or Ainu characters (γ‚’γ‚€γƒŒζ–‡ε­—, ainu moji), are a set of characters discovered around 1886 on the Japanese island of Hokkaido. At the time of their discovery, they were believed to be a genuine script, but this view is not generally supported today.

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πŸ”— Holocene Extinction

πŸ”— Environment πŸ”— Geology πŸ”— Extinction

The Holocene extinction, otherwise referred to as the sixth mass extinction or Anthropocene extinction, is an ongoing extinction event of species during the present Holocene epoch (with the more recent time sometimes called Anthropocene) as a result of human activity. The included extinctions span numerous families of plants and animals, including mammals, birds, amphibians, reptiles and arthropods. With widespread degradation of highly biodiverse habitats such as coral reefs and rainforests, as well as other areas, the vast majority of these extinctions are thought to be undocumented, as the species are undiscovered at the time of their extinction, or no one has yet discovered their extinction. The current rate of extinction of species is estimated at 100 to 1,000 times higher than natural background rates.

The Holocene extinction includes the disappearance of large land animals known as megafauna, starting at the end of the last glacial period. Megafauna outside of the African mainland (thus excluding Madagascar), which did not evolve alongside humans, proved highly sensitive to the introduction of new predation, and many died out shortly after early humans began spreading and hunting across the Earth (many African species have also gone extinct in the Holocene, but – with few exceptions – megafauna of the mainland was largely unaffected until a few hundred years ago). These extinctions, occurring near the Pleistocene–Holocene boundary, are sometimes referred to as the Quaternary extinction event.

The most popular theory is that human overhunting of species added to existing stress conditions as the extinction coincides with human emergence. Although there is debate regarding how much human predation affected their decline, certain population declines have been directly correlated with human activity, such as the extinction events of New Zealand and Hawaii. Aside from humans, climate change may have been a driving factor in the megafaunal extinctions, especially at the end of the Pleistocene.

Ecologically, humanity has been noted as an unprecedented "global superpredator" that consistently preys on the adults of other apex predators, and has worldwide effects on food webs. There have been extinctions of species on every land mass and in every ocean: there are many famous examples within Africa, Asia, Europe, Australia, North and South America, and on smaller islands. Overall, the Holocene extinction can be linked to the human impact on the environment. The Holocene extinction continues into the 21st century, with meat consumption, overfishing, and ocean acidification and the decline in amphibian populations being a few broader examples of a cosmopolitan decline in biodiversity. Human population growth and increasing per capita consumption are considered to be the primary drivers of this decline.

The 2019 Global Assessment Report on Biodiversity and Ecosystem Services, published by the United Nations' Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, posits that roughly one million species of plants and animals face extinction within decades as the result of human actions.

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πŸ”— Kopi Luwak

πŸ”— Food and drink πŸ”— Food and drink/Beverages πŸ”— Animal rights πŸ”— Southeast Asia

Kopi luwak (Indonesian pronunciation: [ˈkopi ˈlu.aΚ”]), also known as civet coffee, is a coffee that consists of partially digested coffee cherries, which have been eaten and defecated by the Asian palm civet (Paradoxurus hermaphroditus). The cherries are fermented as they pass through a civet's intestines, and after being defecated with other fecal matter, they are collected. These civets are increasingly caught in the wild and traded for this purpose.

Kopi luwak is produced mainly on the Indonesian islands of Sumatra, Java, Bali, Sulawesi, and in East Timor. It is also widely gathered in the forest or produced in farms in the islands of the Philippines, where the product is called kape motit in the Cordillera region, kapΓ© alamΓ­d in Tagalog areas, kapΓ© melΓ΄ or kapΓ© musang in Mindanao, and kahawa kubing in the Sulu Archipelago.

Kopi luwak is also produced in Palawan's Langogan Valley. The beans from droppings of the Asian palm civet and Palawan binturong (Arctictis binturong whitei) are collected from the forest floor and cleaned.

Producers of the coffee beans argue that the process may improve coffee through two mechanisms: selection, where civets choose to eat only certain cherries; and digestion, where biological or chemical mechanisms in the animals' digestive tracts alter the composition of the coffee cherries.

The traditional method of collecting feces from wild Asian palm civets has given way to an intensive farming method, in which the palm civets are kept in battery cages and are force-fed the cherries. This method of production has raised ethical concerns about the treatment of civets and the conditions they are made to live in, which include isolation, poor diet, small cages, and a high mortality rate.

Although kopi luwak is a form of processing rather than a variety of coffee, it has been called one of the most expensive coffees in the world, with retail prices reaching $100 per kilogram ($45/lb) for farmed beans and $1,300 per kilogram ($590/lb) for wild-collected beans. Another epithet for it is the "Holy Grail of coffees".

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πŸ”— LOVEINT

πŸ”— United States πŸ”— Espionage πŸ”— Law Enforcement

LOVEINT is the practice of intelligence service employees making use of their extensive monitoring capabilities to spy on their love interest or spouse. The term was coined in resemblance to intelligence terminology such as SIGINT, COMINT or HUMINT.

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πŸ”— Cowsay

πŸ”— Computing πŸ”— Computing/Software πŸ”— Computing/Free and open-source software πŸ”— Linux πŸ”— Perl

cowsay is a program that generates ASCII art pictures of a cow with a message. It can also generate pictures using pre-made images of other animals, such as Tux the Penguin, the Linux mascot. It is written in Perl. There is also a related program called cowthink, with cows with thought bubbles rather than speech bubbles. .cow files for cowsay exist which are able to produce different variants of "cows", with different kinds of "eyes", and so forth. It is sometimes used on IRC, desktop screenshots, and in software documentation. It is more or less a joke within hacker culture, but has been around long enough that its use is rather widespread. In 2007, it was highlighted as a Debian package of the day.

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πŸ”— Sayre's law

πŸ”— Politics πŸ”— Sociology

Sayre's law states, in a formulation quoted by Charles Philip Issawi: "In any dispute the intensity of feeling is inversely proportional to the value of the issues at stake." By way of corollary, it adds: "That is why academic politics are so bitter." Sayre's law is named after Wallace Stanley Sayre (1905–1972), U.S. political scientist and professor at Columbia University.

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