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🔗 Color 🔗 Visual arts

Non-photo blue (or non-repro blue) is a common tool used in the graphic design and print industry.

🔗 China

Counting rods (traditional Chinese: 籌; simplified Chinese: 筹; pinyin: chóu; Japanese: 算木; rōmaji: sangi; Korean: sangaji) are small bars, typically 3–14 cm long, that were used by mathematicians for calculation in ancient East Asia. They are placed either horizontally or vertically to represent any integer or rational number.

The written forms based on them are called rod numerals. They are a true positional numeral system with digits for 1–9 and a blank for 0, from the Warring states period (circa 475 BCE) to the 16th century.

🔗 Germany 🔗 Military history 🔗 Death 🔗 Lists 🔗 Politics 🔗 LGBT studies 🔗 Discrimination 🔗 Military history/World War II 🔗 Military history/German military history 🔗 Politics/Fascism 🔗 Jewish history 🔗 Military history/European military history

This is an incomplete list of documented attempts to assassinate Adolf Hitler.

All attempts occurred in the German Reich, except where noted. All attempts involved citizens of the German Reich, except where noted. No fewer than 42 plots have been uncovered by historians. However, the true numbers cannot be accurately determined due to an unknown number of undocumented cases.

🔗 Aviation 🔗 History 🔗 Spaceflight 🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Spaceflight/Timeline of spaceflight working group 🔗 Physics 🔗 Lists 🔗 Military history/World War II 🔗 Military history/Cold War 🔗 Rocketry 🔗 Military history/European military history 🔗 Military history/British military history

Spaceflight as a practical endeavor began during World War II with the development of operational liquid-fueled rockets. Beginning life as a weapon, the V-2 was pressed into peaceful service after the war at the United States' White Sands Missile Range as well as the Soviet Union's Kapustin Yar. This led to a flourishing of missile designs setting the stage for the exploration of space. The small American WAC Corporal rocket was evolved into the Aerobee, a much more powerful sounding rocket. Exploration of space began in earnest in 1947 with the flight of the first Aerobee, 46 of which had flown by the end of 1950. These and other rockets, both Soviet and American, returned the first direct data on air density, temperature, charged particles and magnetic fields in the Earth's upper atmosphere.

By 1948, the United States Navy had evolved the V-2 design into the Viking capable of more than 100 miles (160 km) in altitude. The first Viking to accomplish this feat, number four, did so 10 May 1950. The Soviet Union developed a virtual copy of the V-2 called the R-1, which first flew in 1948. Its longer-ranged successor, the R-2, entered military service in 1950. This event marked the entry of both superpowers into the post-V-2 rocketry era.

🔗 Philosophy 🔗 Philosophy/Contemporary philosophy 🔗 Philosophy/Ethics

The trolley problem is a thought experiment in ethics. It is generally considered to represent a classic clash between two schools of moral thought, utilitarianism and deontological ethics. The general form of the problem is this:

There is a runaway trolley barreling down the railway tracks. Ahead, on the tracks, there are five people tied up and unable to move. The trolley is headed straight for them. You are standing some distance off in the train yard, next to a lever. If you pull this lever, the trolley will switch to a different set of tracks. However, you notice that there is one person on the side track. You have two options:

1. Do nothing and allow the trolley to kill the five people on the main track.
2. Pull the lever, diverting the trolley onto the side track where it will kill one person.

Which is the more ethical option? Or, more simply: What is the right thing to do?

Philippa Foot introduced this modern form of the problem in 1967. Judith Thomson, Frances Kamm, and Peter Unger have also analysed the dilemma extensively.

Earlier forms of the problem predated Foot's publication. Frank Chapman Sharp included a version in a moral questionnaire given to undergraduates at the University of Wisconsin in 1905. In this variation, the railway's switchman controlled the switch, and the lone individual to be sacrificed (or not) was the switchman's child. The German legal scholar Hans Welzel discussed a similar problem in 1951. In his commentary on the Talmud, published long before his death in 1953, Avrohom Yeshaya Karelitz discussed the similar question of whether it is ethical to deflect a projectile from a larger crowd toward a smaller one.

Beginning in 2001, the trolley problem and its variants have been used extensively in empirical research on moral psychology. Trolley problems have also been a topic of popular books. The problem arises in discussing the ethics of autonomous vehicle design, which may require programming to choose whom or what to strike when a collision appears to be unavoidable.

🔗 Germany 🔗 Literature 🔗 Linguistics

"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.

🔗 Philosophy 🔗 Philosophy/Logic

Abductive logic programming (ALP) is a high-level knowledge-representation framework that can be used to solve problems declaratively based on abductive reasoning. It extends normal logic programming by allowing some predicates to be incompletely defined, declared as abducible predicates. Problem solving is effected by deriving hypotheses on these abducible predicates (abductive hypotheses) as solutions of problems to be solved. These problems can be either observations that need to be explained (as in classical abduction) or goals to be achieved (as in normal logic programming). It can be used to solve problems in diagnosis, planning, natural language and machine learning. It has also been used to interpret negation as failure as a form of abductive reasoning.

🔗 Film 🔗 Film/Filmmaking

The zoöpraxiscope (initially named zoographiscope and zoogyroscope) is an early device for displaying moving images and is considered an important predecessor of the movie projector. It was conceived by photographic pioneer Eadweard Muybridge in 1879 (and built for him by January 1880 to project his famous chronophotographic pictures in motion and thus prove that these were authentic). Muybridge used the projector in his public lectures from 1880 to 1895. The projector used 16" glass disks onto which Muybridge had an unidentified artist paint the sequences as silhouettes. This technique eliminated the backgrounds and enabled the creation of fanciful combinations and additional imaginary elements. Only one disk used photographic images, of a horse skeleton posed in different positions. A later series of 12" discs, made in 1892–1894, used outlines drawn by Erwin F. Faber that were printed onto the discs photographically, then colored by hand. These colored discs were probably never used in Muybridge's lectures. All images of the known 71 disks, including those of the photographic disk, were rendered in elongated form to compensate the distortion of the projection. The projector was related to other projecting phenakistiscopes and used some slotted metal shutter discs that were interchangeable for different picture disks or different effects on the screen. The machine was hand-cranked.

The device appears to have been one of the primary inspirations for Thomas Edison and William Kennedy Dickson's Kinetoscope, the first commercial film exhibition system. Images from all of the known seventy-one surviving zoopraxiscope discs have been reproduced in the book Eadweard Muybridge: The Kingston Museum Bequest (The Projection Box, 2004).

...it is the first apparatus ever used, or constructed, for synthetically demonstrating movements analytically photographed from life, and in its resulting effects is the prototype of the various instruments which, under a variety of names, are used for a similar purpose at the present day.

As stipulated in Muybridge's will the original machine and disks in his possession were left to Kingston upon Thames, where they are still kept in the Kingston Museum Muybridge Bequest Collection (except for four discs that are in other collections, including those of the Cinémathèque française and the National Technical Museum in Prague).

Muybridge also produced a series of 50 different paper 'Zoopraxiscope discs' (basically phenakistiscopes), again with pictures drawn by Erwin F. Faber. The discs were intended for sale at the 1893 World's Fair at Chicago, but seem to have sold very poorly and are quite rare. The discs were printed in black-and-white, with twelve different discs also produced as chromolithographed versions. Of the coloured versions only four different ones are known to still exist with a total of five or six extant copies.

🔗 New York City 🔗 Engineering

The Citicorp Center engineering crisis was the discovery, in 1978, of a significant structural flaw in Citicorp Center, then a recently completed skyscraper in New York City, and the subsequent effort to quietly make repairs over the next few months. The building, now known as Citigroup Center, occupied an entire block and was to be the headquarters of Citibank. Its structure, designed by William LeMessurier, had several unusual design features, including a raised base supported by four offset stilts, and diagonal bracing which absorbed wind loads from upper stories.

In the original design, potential wind loads for the building were calculated incorrectly. The flaw was discovered by Diane Hartley, an undergraduate student at Princeton University who was writing a thesis on the building, and was communicated to the firm responsible for the structural design. LeMessurier was subsequently lauded for acknowledging his error and orchestrating a successful repair effort. Estimates at the time suggested that the building could be toppled by a 70-mile-per-hour (110 km/h) wind, with possibly many people killed as a result. The crisis was kept secret until 1995 and Hartley had no knowledge of the significance of her work until after that time.

🔗 Biography 🔗 Portugal

Álvaro de Campos (Portuguese pronunciation: [ˈalvɐɾu ðɨ ˈkɐ̃puʃ]; October 15, 1890 – November 30, 1935) was one of the poet Fernando Pessoa's various heteronyms, widely known by his powerful and wrathful writing style. According to his author, this alter ego was born in Tavira, Portugal, studied mechanical engineering and finally graduated in ship engineering in Glasgow. After a journey in Ireland, Campos sailed to the Orient and wrote his poem "Opiario" in the Suez Canal "onboard". He worked in 'Barrow-on-Furness' (sic) (of which Pessoa wrote a poem about) and Newcastle-on-Tyne (1922). Unemployed, Campos returned to Lisbon in 1926 (he wrote then the poem "Lisbon Revisited"), where he lived ever since. He was born in October, 1890, but Pessoa didn't put an end to the life of Campos, so he would have survived his author who died in November, 1935. Campos' works may be split in three phases: the decadent phase, the futuristic phase and the decadent (sad) phase. He chose Whitman and Marinetti as masters, showing some similarities with their works, mainly in the second phase: hymns like "Ode Triunfal", "Ode Marítima", and "Ultimatum" praise the power of the rising technology, the strength of the machines, the dark side of the industrial civilization, and an enigmatic love for the machines. The first phase (marked by the poem Opiário) shared some of its pessimism with Pessoa's friend Mário de Sá-Carneiro, one of his co-workers in Orpheu magazine. In the last phase, Pessoa drops the mask, and reveals through Campos all the emptiness and nostalgy that grew during his last years of life. In his last phase Campos wrote the poems "Lisbon Revisited" and the well-known "Tobaco Shop".

"I always want to be the thing I feel kinship with...
To feel everything in every way,
To hold all opinions,
To be sincere contradicting oneself every minute..."