Have a deep view into what people are curious about.

🔗 Aviation 🔗 Military history 🔗 Military history/Military aviation 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Aviation/aircraft 🔗 Aviation/aircraft engine

The Aircraft Nuclear Propulsion (ANP) program and the preceding Nuclear Energy for the Propulsion of Aircraft (NEPA) project worked to develop a nuclear propulsion system for aircraft. The United States Army Air Forces initiated Project NEPA on May 28, 1946. NEPA operated until May 1951, when the project was transferred to the joint Atomic Energy Commission (AEC)/USAF ANP. The USAF pursued two different systems for nuclear-powered jet engines, the Direct Air Cycle concept, which was developed by General Electric, and Indirect Air Cycle, which was assigned to Pratt & Whitney. The program was intended to develop and test the Convair X-6, but was cancelled in 1961 before that aircraft was built. The total cost of the program from 1946 to 1961 was about $1 billion.

🔗 United States 🔗 Military history 🔗 Philosophy 🔗 Philosophy/Logic 🔗 Military history/Military biography

The McNamara fallacy (also known as the quantitative fallacy), named for Robert McNamara, the US Secretary of Defense from 1961 to 1968, involves making a decision based solely on quantitative observations (or metrics) and ignoring all others. The reason given is often that these other observations cannot be proven.

The first step is to measure whatever can be easily measured. This is OK as far as it goes. The second step is to disregard that which can't be easily measured or to give it an arbitrary quantitative value. This is artificial and misleading. The third step is to presume that what can't be measured easily really isn't important. This is blindness. The fourth step is to say that what can't be easily measured really doesn't exist. This is suicide.

The fallacy refers to McNamara's belief as to what led the United States to defeat in the Vietnam War—specifically, his quantification of success in the war (e.g., in terms of enemy body count), ignoring other variables.

🔗 Electronics 🔗 Guild of Copy Editors

The capacitor plague was a problem related to a higher-than-expected failure rate of non-solid aluminum electrolytic capacitors, between 1999 and 2007, especially those from some Taiwanese manufacturers, due to faulty electrolyte composition that caused corrosion accompanied by gas generation, often rupturing the case of the capacitor from the build-up of pressure.

High failure rates occurred in many well-known brands of electronics, and were particularly evident in motherboards, video cards, and power supplies of personal computers.

Vital articles are lists of subjects for which the English Wikipedia should have corresponding featured-class articles. They serve as centralized watchlists to track the status of Wikipedia's most important articles. The very most important articles are in Level 1.

This page constitutes Level 3 of the vital articles list and includes approximately 1,000 articles. All articles from higher levels are also included in lower levels. For example, all 100 subjects on the Level 2 list (shown on this page in bold font) are included here in Level 3. And the Level 2 list also includes the 10 subjects on Level 1 (shown on this page in bold italics). A larger Level 4 list of 10,000 articles also exists, and a Level 5 list of 50,000 articles is in the process of being created.

Articles are labelled as:

These symbols and article counts are updated daily by User:cewbot.

• The bot only update counter with the pattern "(000 articles)" in section title.
• All attributes of articles get from corresponding categories.
• The bot will automatically update the summary table if there are summary table marks.

This list is tailored to the English-language Wikipedia. There is also a list of one thousand articles considered vital to Wikipedias of all languages, as well as Vital Article lists tailored to different Wikipedia languages accessible via the languages sidebar.

Articles should not be added or removed from this list without a consensus on the talk page. For more information on this list and the process for adding or removing articles, please see the Frequently Asked Questions (FAQ) page.

🔗 Sanitation

A shit flow diagram (also called excreta flow diagram or SFD) is a high level technical drawing used to display how excreta moves through a location, and functions as a tool to identify where improvements are needed. The diagram has a particular focus on treatment of the waste, and its final disposal or use. SFDs are most often used in developing countries.

🔗 Computing 🔗 Software 🔗 Software/Computing

"Everything is a file" is an idea that Unix, and its derivatives, handle input/output to and from resources such as documents, hard-drives, modems, keyboards, printers and even some inter-process and network communications as simple streams of bytes exposed through the filesystem name space. Exceptions include semaphores, processes and threads.

The advantage of this approach is that the same set of tools, utilities and APIs can be used on a wide range of resources and a number of file types. When a file is opened, a file descriptor is created, using the file path as an addressing system. The file descriptor is then a byte stream I/O interface on which file operations are performed. File descriptors are also created for objects such as anonymous pipes and network sockets - and therefore a more accurate description of this feature is Everything is a file descriptor.

Additionally, a range of pseudo and virtual filesystems exists which exposes internal kernel data, such as information about processes, to user space in a hierarchical file-like structure. These are mounted into the single file hierarchy.

An example of this purely virtual filesystem is under /proc that exposes many system properties as files. All of these files, in the broader sense of the word, have standard Unix file attributes such as an owner and access permissions, and can be queried by the same classic Unix tools and filters. However, this is not universally considered a fast or portable approach. Some operating systems do not mount /proc by default due to security or speed concerns, relying on system calls instead. It is, though, used heavily by Linux shell utilities, such as procps ps implementation and the widely installed on embedded systems BusyBox. Android Toolbox program depend on it as well.

🔗 Psychology

The James–Lange theory is a hypothesis on the origin and nature of emotions and is one of the earliest theories of emotion within modern psychology. It was developed by philosopher John Dewey and named for two 19th-century scholars, William James and Carl Lange (see modern criticism for more on the theory's origin). The basic premise of the theory is that physiological arousal instigates the experience of emotion. Previously people considered emotions as reactions to some significant events or their features, i.e. events come first, and then there is an emotional response. James-Lange theory proposed that the state of the body can induce emotions or emotional dispositions. In other words, this theory suggests that when we feel teary, it generates a disposition for sad emotions; when our heartbeat is out of normality, it makes us feel anxiety. Instead of feeling an emotion and subsequent physiological (bodily) response, the theory proposes that the physiological change is primary, and emotion is then experienced when the brain reacts to the information received via the body's nervous system. It proposes that each specific category of emotion is attached to a unique and different pattern of physiological arousal and emotional behaviour in reaction due to an exciting stimulus.

The theory has been criticized and modified over the course of time, as one of several competing theories of emotion. Modern theorists have built on its ideas by proposing that the experience of emotion is modulated by both physiological feedback and other information, rather than consisting solely of bodily changes, as James suggested. Psychologist Tim Dalgleish states that most modern affective neuroscientists would support such a viewpoint. In 2002, a research paper on the autonomic nervous system stated that the theory has been "hard to disprove".

🔗 Biography 🔗 Germany 🔗 Mexico 🔗 Biography/arts and entertainment 🔗 Anarchism

B. Traven (German: [ˈbeː ˈtʁaːvn̩]; Bruno Traven in some accounts) was the pen name of a presumably German novelist, whose real name, nationality, date and place of birth and details of biography are all subject to dispute. One of the few certainties about Traven's life is that he lived for years in Mexico, where the majority of his fiction is also set—including The Treasure of the Sierra Madre (1927). The film adaptation of the same name won three Academy Awards in 1948.

Virtually every detail of Traven's life has been disputed and hotly debated. There were many hypotheses on the true identity of B. Traven, some of them wildly fantastic. The person most commonly identified as Traven is Ret Marut, a German stage actor and anarchist who supposedly left Europe for Mexico around 1924 and who had edited an anarchist newspaper in Germany called Der Ziegelbrenner (The Brick Burner). Marut is thought to have operated under the "B. Traven" pseudonym, although no details are known about Marut's life before 1912, and many hold that "Ret Marut" was in fact also a pseudonym.

Some researchers further argue that Marut/Traven's original name was Otto Feige and that he was born in Schwiebus in Brandenburg, modern-day Świebodzin in Poland. This theory is not universally accepted. B. Traven in Mexico is also connected with the names of Berick Traven Torsvan and Hal Croves, both of whom appeared and acted in different periods of the writer's life. Both, however, denied being Traven and claimed that they were his literary agents only, representing him in contacts with his publishers.

B. Traven is the author of twelve novels, one book of reportage and several short stories, in which the sensational and adventure subjects combine with a critical attitude towards capitalism. B. Traven's best known works include the novels The Death Ship from 1926, The Treasure of the Sierra Madre from 1927 (filmed in 1948 by John Huston), and the so-called "Jungle Novels", also known as the Caoba cyclus (from the Spanish word caoba, meaning mahogany). The Jungle Novels are a group of six novels (including The Carreta and Government), published in the years 1930–1939 and set among Mexican Indians just before and during the Mexican Revolution in the early 20th century. B. Traven's novels and short stories became very popular as early as the interwar period and retained this popularity after the Second World War; they were also translated into many languages. Most of B. Traven's books were published in German first, with their English editions appearing later; nevertheless, the author always claimed that the English versions were the original ones and that the German versions were only their translations. This claim is mostly treated by Traven scholars as a diversion or a joke, although there are those who accept it.

🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Equine 🔗 Military history/Medieval warfare

The Great Stirrup Controversy is the academic debate about the Stirrup Thesis, the theory that feudalism in Europe developed largely as a result of the introduction of the stirrup to cavalry in the 8th century CE. It relates to the hypothesis suggested by Lynn Townsend White Jr. in his 1962 book, Medieval Technology and Social Change. White believed that the stirrup enabled heavy cavalry and shock combat, which in turn prompted the Carolingian dynasty of the 8th and 9th centuries to organize its territory into a vassalage system, rewarding mounted warriors with land grants for their service. White's book has proved very influential, but others have accused him of speculation, oversimplification, and ignoring contradictory evidence on the subject. Scholars have debated whether the stirrup actually provided the impetus for this social change, or whether the rise of heavy cavalry resulted from political changes in Medieval Europe.

🔗 History 🔗 Mathematics 🔗 Books 🔗 Greece 🔗 History of Science

The Archimedes Palimpsest is a parchment codex palimpsest, originally a Byzantine Greek copy of a compilation of Archimedes and other authors. It contains two works of Archimedes that were thought to have been lost (the Ostomachion and the Method of Mechanical Theorems) and the only surviving original Greek edition of his work On Floating Bodies. The first version of the compilation is believed to have been produced by Isidorus of Miletus, the architect of the geometrically complex Hagia Sophia cathedral in Constantinople, sometime around AD 530. The copy found in the palimpsest was created from this original, also in Constantinople, during the Macedonian Renaissance (c. AD 950), a time when mathematics in the capital was being revived by the former Greek Orthodox bishop of Thessaloniki Leo the Geometer, a cousin of the Patriarch.

Following the sack of Constantinople by Western crusaders in 1204, the manuscript was taken to an isolated Greek monastery in Palestine, possibly to protect it from occupying crusaders, who often equated Greek script with heresy against their Latin church and either burned or looted many such texts (including at least two other copies of Archimedes). The complex manuscript was not appreciated at this remote monastery and was soon overwritten (1229) with a religious text. In 1899, nine hundred years after it was written, the manuscript was still in the possession of the Greek church, and back in Istanbul, where it was catalogued by the Greek scholar Papadopoulos-Kerameus, attracting the attention of Johan Heiberg. Heiberg visited the church library and was allowed to make detailed photographs in 1906. Most of the original text was still visible, and Heiberg published it in 1915. In 1922 the manuscript went missing in the midst of the evacuation of the Greek Orthodox library in Istanbul, during a tumultuous period following the World War I. Concealed for over 70 years by a Western businessman, forged pictures were painted on top of some text to increase resale value. Unable to sell the book privately, in 1998 the businessman's daughter risked a public auction in New York contested by the Greek church; the U.S. court ruled for the auction, and the manuscript was purchased by an anonymous buyer (rumored to be Jeff Bezos). The texts under the forged pictures, and previously unreadable texts, were revealed by analyzing images produced by ultraviolet, infrared, visible and raking light, and X-ray.

All images and transcriptions are now freely available on the web at the Archimedes Digital Palimpsest under the Creative Commons License CC BY.