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🔗 CD-i

🔗 Video games

The Compact Disc-Interactive (CD-I, later CD-i) is a digital optical disc data storage format that was mostly developed and marketed by Dutch company Philips. It was created as an extension of CDDA and CD-ROM and specified in the Green Book, co-developed by Philips and Sony, to combine audio, text and graphics. The two companies initially expected to impact the education/training, point of sale, and home entertainment industries, but CD-i eventually became best known for its video games.

CD-i media physically have the same dimensions as CD, but with up to 744 MiB of digital data storage, including up to 72 minutes of full motion video. CD-i players were usually standalone boxes that connect to a standard television; some less common setups included integrated CD-i television sets and expansion modules for personal computers. Most players were created by Philips; the format was licensed by Philips and Microware for use by other manufacturers, notably Sony who released professional CD-i players under the "Intelligent Discman" brand. Unlike CD-ROM drives, CD-i players are complete computer systems centered around dedicated Motorola 68000-based microprocessors and its own operating system called CD-RTOS, which is an acronym for "Compact Disc – Real Time Operating System".

Media released on the format included video games and "edutainment" and multimedia reference titles, such as interactive encyclopedias and museum tours – which were popular before public Internet access was widespread – as well as business software. Philips's CD-i system also implemented Internet features, including subscriptions, web browsing, downloading, e-mail, and online play. Philips's aim with its players was to introduce interactive multimedia content for the general public by combining features of a CD player and game console, but at a lower price than a personal computer with a CD-ROM drive.

Authoring kits for the format were released first in 1988, and the first player aimed for home consumers, Philips's CDI 910/205, at the end of 1991, initially priced around US$1,000 (equivalent to $1,877 in 2019), and capable of playing interactive CD-i discs, Audio CDs, CD+G (CD+Graphics), Photo CDs and Video CDs (VCDs), though the latter required an optional "Digital Video Card" to provide MPEG-1 decoding. Initially marketed to consumers as "home entertainment systems", and in later years as a "gaming platform", CD-i did not manage to find enough success in the market, and was mostly abandoned by Philips in 1996. The format continued to be supported for licensees for a few more years after.

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  • "CD-i" | 2021-01-01 | 13 Upvotes 5 Comments

🔗 Eagle Cash

🔗 Economics

Eagle Cash (stylized as EagleCash), and sister program EZpay, are cash management applications that use stored-value card technology to process financial transactions in "closed-loop" operating environments. The United States Department of the Treasury sponsors the programs for the U.S. Armed Forces. The Federal Reserve Bank of Boston administers the programs for the Treasury, and they are in use at approved U.S. military facilities inside and outside the continental United States. The systems use a plastic payment card, similar to a credit or debit card, which has an embedded microchip that tracks the card's balance and interfaces with encrypted card readers. This method allows soldiers to purchase goods and services at U.S. military posts and canteens, without carrying cash, or manage their personal bank accounts while on deployment or in training. The program reduces the amount of American currency required overseas, reduces theft, saves thousands of man-hours in labor, helps reduce the risk of transporting cash in combat environments, and increases security and convenience for service members. It helped reduce or eliminate the need for cash and money orders.

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🔗 Great Britain road numbering scheme

🔗 Highways 🔗 Road transport 🔗 Transport in Scotland 🔗 Highways/United Kingdom Roads 🔗 UK geography

The Great Britain road numbering scheme is a numbering scheme used to classify and identify all roads in Great Britain. Each road is given a single letter, which represents the road's category, and a subsequent number, of 1 to 4 digits. Introduced to arrange funding allocations, the numbers soon became used on maps and as a method of navigation. Two sub-schemes exist: one for motorways, and another for non-motorway roads. While some major roads form part of the International E-road network, no E-routes are signposted in Great Britain, or the rest of the UK.

The scheme applies only to Great Britain (England, Scotland and Wales); a similar system is used in Northern Ireland, as well as outside the UK in the Isle of Man, Jersey and British overseas territories. These other numbering schemes use similar conventions.

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🔗 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.

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🔗 Weather Underground Organization

🔗 United States 🔗 Terrorism 🔗 Socialism 🔗 Michigan 🔗 Chicago

The Weather Underground Organization (WUO), commonly known as the Weather Underground, was a radical left militant organization active in the late 1960s and 1970s, founded on the Ann Arbor campus of the University of Michigan. It was originally called the Weathermen. The WUO organized in 1969 as a faction of Students for a Democratic Society (SDS) largely composed of the national office leadership of SDS and their supporters. Beginning in 1974, the organization's express political goal was to create a revolutionary party to overthrow American imperialism.

The FBI described the WUO as a domestic terrorist group, with revolutionary positions characterized by black power and opposition to the Vietnam War. The WUO took part in domestic attacks such as the jailbreak of Timothy Leary in 1970. The "Days of Rage" was the WUO's first riot in October 1969 in Chicago, timed to coincide with the trial of the Chicago Seven. In 1970, the group issued a "Declaration of a State of War" against the United States government under the name "Weather Underground Organization".

In the 1970s, the WUO conducted a bombing campaign targeting government buildings and several banks. Some attacks were preceded by evacuation warnings, along with threats identifying the particular matter that the attack was intended to protest. Three members of the group were killed in an accidental Greenwich Village townhouse explosion, but none were killed in any of the bombings. The WUO communiqué issued in connection with the bombing of the United States Capitol on March 1, 1971 indicated that it was "in protest of the U.S. invasion of Laos". The WUO asserted that its May 19, 1972 bombing of the Pentagon was "in retaliation for the U.S. bombing raid in Hanoi". The WUO announced that its January 29, 1975 bombing of the United States Department of State building was "in response to the escalation in Vietnam".

The WUO began to disintegrate after the United States reached a peace accord in Vietnam in 1973, and it was defunct by 1977.

The group took its name from Bob Dylan's lyric, "You don't need a weatherman to know which way the wind blows", from the song "Subterranean Homesick Blues" (1965). That Dylan line was also the title of a position paper distributed at an SDS convention in Chicago on June 18, 1969. This founding document called for a "White fighting force" to be allied with the "Black Liberation Movement" and other radical movements to achieve "the destruction of U.S. imperialism and form a classless communist world".

🔗 Cosmic Latte

🔗 Color

Cosmic latte is the average color of the universe, found by a team of astronomers from Johns Hopkins University. In 2001, Karl Glazebrook and Ivan Baldry determined that the average color of the universe was a greenish white, but they soon corrected their analysis in a 2002 paper in which they reported that their survey of the light from over 200,000 galaxies averaged to a slightly beigeish white. The hex triplet value for cosmic latte is #FFF8E7.

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🔗 Leary–Lettvin Debate

🔗 United States

The Leary–Lettvin debate was a May 3, 1967 debate between Dr. Jerome Lettvin, a medical doctor and professor at MIT, and Dr. Timothy Leary, a licensed psychologist, about the merits and dangers of the hallucinogenic drug LSD. It took place in the Kresge Auditorium at the Massachusetts Institute of Technology.

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🔗 Atlantropa

🔗 Architecture

Atlantropa, also referred to as Panropa, was a gigantic engineering and colonisation idea devised by the German architect Herman Sörgel in the 1920s and promoted by him until his death in 1952. Its central feature was a hydroelectric dam to be built across the Strait of Gibraltar, which would have provided enormous amounts of hydroelectricity and would have led to the lowering of the surface of the Mediterranean Sea by up to 200 metres (660 ft), opening up large new lands for settlement, for example in the Adriatic Sea. The project proposed four additional major dams as well:

  • Across the Dardanelles to hold back the Black Sea
  • Between Sicily and Tunisia to provide a roadway and further lower the inner Mediterranean
  • On the Congo River below its Kwah River tributary to refill the Mega-Chad basin around Lake Chad providing fresh water to irrigate the Sahara and creating a shipping lane to the interior of Africa
  • Suez Canal extension and locks to maintain Red Sea connection

Sörgel saw his scheme, projected to take over a century, as a peaceful European-wide alternative to the Lebensraum concepts that later became one of the stated reasons for Nazi Germany's conquest of new territories. Atlantropa would provide land and food, employment, electric power, and most of all, a new vision for Europe and neighbouring Africa.

The Atlantropa movement, through its several decades, was characterised by four constants:

  • Pacifism, in its promises of using technology in a peaceful way;
  • Pan-European sentiment, seeing the project as a way to unite a war-torn Europe;
  • Eurocentric attitudes to Africa (which was to become united with Europe into "Atlantropa" or Eurafrica), and
  • Neo-colonial geopolitics, which saw the world divided into three blocs—America, Asia, and Atlantropa.

Active support was limited to architects and planners from Germany and a number of other primarily northern European countries. Critics derided it for various faults, ranging from lack of any cooperation of Mediterranean countries in the planning to the impacts it would have had on the historic coastal communities left stranded inland when the sea receded. The project reached great popularity in the late 1920s to the early 1930s, and for a short period again, in the late 1940s to the early 1950s, but soon disappeared from general discourse again after Sörgel's death.

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🔗 Romanesco broccoli has a form naturally approximating a fractal

🔗 Food and drink 🔗 Plants

Romanesco broccoli (also known as Roman cauliflower, Broccolo Romanesco, Romanesque cauliflower, or simply Romanesco) is an edible flower bud of the species Brassica oleracea. First documented in Italy in the 16th century, it is chartreuse in color, and has a form naturally approximating a fractal. When compared to a traditional cauliflower, it has a firmer texture and delicate, nutty flavor.

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🔗 Dunning–Kruger Effect

The Dunning–Kruger effect is a cognitive bias in which people with low ability at a task overestimate their ability. It is related to the cognitive bias of illusory superiority and comes from people's inability to recognize their lack of ability. Without the self-awareness of metacognition, people cannot objectively evaluate their level of competence.

As described by social psychologists David Dunning and Justin Kruger, the bias results from an internal illusion in people of low ability and from an external misperception in people of high ability; that is, "the miscalibration of the incompetent stems from an error about the self, whereas the miscalibration of the highly competent stems from an error about others". Colloquially, people experiencing this bias are said to be "on Mount Stupid".

But in spite of the inherent appeal of Dunning and Kruger's claimed results, which align with many people's just world theories, their conclusions are strongly challenged when subjected to mathematical analysis and comparisons across cultures.