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๐Ÿ”— Vestas Sailrocket

๐Ÿ”— Sailing

The Vestas Sailrocket was built to capture the sailing speed record competing in the B-class for 150 to 235 square feet of sail. It is piloted by the project leader Paul Larsen and sponsored by Danish wind turbines manufacturer Vestas. In 2008 the first version reached a reported unofficial speed of 52.22 knots (96.71ย km/h), before crashing.

After being upgraded to a second version, the Vestas Sailrocket 2 began a campaign to break speed records in November 2012 off Walvis Bay, Namibia. On 12 November, it made a 54.08 knots (100.16ย km/h) run over a 500 metres (1,600ย ft) distance, then 59.23 knots (109.69ย km/h) on the 16th. It attained 55.32 knots (102.45ย km/h) on a one-mile run on the 18th and simultaneously 59.38 knots (109.97ย km/h) on 500m. On 24 November, with wind speeds at roughly 25 knots (46ย km/h), it ran the 500m course at 65.45 knots (121.21ย km/h) with a 68.01 knots (125.95ย km/h) peak. Both records are ratified by the World Sailing Speed Record Council (WSSRC) for the 500m and the mile.

A Swiss team of ร‰cole Polytechnique Fรฉdรฉrale de Lausanne university students and engineers, including members involved in the development of previous record-holder Hydroptรจre, formed in October 2019 to develop a new hydrofoil boat, SP80, to exceed the Vestas Sailrocket 2 record in 2022, with a target speed of 80 knots. As of April 2023, the speed record attempts were pushed back to 2024 and are scheduled to take place in Leucate.

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๐Ÿ”— Valeriepieris Circle

๐Ÿ”— Internet culture

The Valeriepieris circle is a South China Sea-centered circular region on the world map that is about 4,000 kilometers (2,500ย mi) in radius and contains more than half the worldโ€™s population. It was named after the Reddit username of Ken Myers, a Texas ESL teacher who first drew attention to the phenomenon in 2013. The map became a meme and was featured in numerous forms of media.

In 2015, the circle was tested by Danny Quah, who verified the claim but moved the circle slightly to exclude most of Japan, and used a globe model rather than a map projection as well as more specific calculations. He calculated that, as of 2015, half of the world's population lived within a 3,300-kilometer (2,050ย mi) radius of the city of Mong Khet in Myanmar.

The most common visual of the circle, originally used by Myers and also featured by io9 and Tech in Asia, used the Winkel tripel projection.

๐Ÿ”— Yo-yo problem

๐Ÿ”— Computing ๐Ÿ”— Computing/Software

In software development, the yo-yo problem is an anti-pattern that occurs when a programmer has to read and understand a program whose inheritance graph is so long and complicated that the programmer has to keep flipping between many different class definitions in order to follow the control flow of the program. It often happens in object-oriented programming. The term comes from comparing the bouncing attention of the programmer to the up-down movement of a toy yo-yo. Taenzer, Ganti, and Podar described the problem by name, explaining: "Often we get the feeling of riding a yoyo when we try to understand one of these message trees."

Most practices of object-oriented programming recommend keeping the inheritance graph as shallow as possible, in part to avoid this problem. The use of composition instead of inheritance is also strongly preferred, although this still requires that a programmer keep multiple class definitions in mind at once.

More generally, the yo-yo problem can also refer to any situation where a person must keep flipping between different sources of information in order to understand a concept.

Object-oriented design techniques such as documenting layers of the inheritance hierarchy can reduce the effect of this problem, as they collect in one place the information that the programmer is required to understand.

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๐Ÿ”— Optic Nerve (GCHQ)

๐Ÿ”— Mass surveillance ๐Ÿ”— Espionage ๐Ÿ”— Politics of the United Kingdom

Optic Nerve is a mass surveillance programme run by the British signals intelligence agency Government Communications Headquarters (GCHQ), with help from the US National Security Agency, that surreptitiously collects private webcam still images from users while they are using a Yahoo! webcam application. As an example of the scale, in one 6-month period, the programme is reported to have collected images from 1.8 million Yahoo! user accounts globally. The programme was first reported on in the media in February 2014, from documents leaked by the former National Security Agency contractor Edward Snowden, but dates back to a prototype started in 2008, and was still active in at least 2012.

The leaked documents describe the users under surveillance as "unselected", meaning that data was collected indiscriminately in bulk from users regardless of whether they were an intelligence target or not. The vast majority of affected users would have been completely innocent of any crime or suspicion of a crime. Optic Nerve as described in the documents collected one still image every 5 minutes per user, attempting to comply with human rights legislation. The images were collected in a searchable database, and used for experiments in facial recognition, to monitor known targets, and to discover new targets. The choice of Yahoo! for surveillance was taken because "Yahoo webcam is known to be used by GCHQ targets". Unlike the US NSA, the UK GCHQ is not required by law to minimise the collection from domestic citizens, so UK citizens could have been targeted on the same level as non-UK citizens.

The story was broken by The Guardian in February 2014, and is based on leaked documents dating to between 2008 and 2012. Yahoo! expressed outrage at the programme, when approached by The Guardian, and subsequently called it "a whole new level of violation of our users' privacy." A GCHQ spokesperson stated "It is a long-standing policy that we do not comment on intelligence matters".

Though there were some limits to which photos security analysts were allowed to see, with bulk searches limited to metadata, security analysts were allowed to see "webcam images associated with similar Yahoo identifiers to your known target".

๐Ÿ”— Freedom to Roam

๐Ÿ”— Environment ๐Ÿ”— Law ๐Ÿ”— Backpacking

The freedom to roam, or "everyman's right", is the general public's right to access certain public or privately owned land, lakes, and rivers for recreation and exercise. The right is sometimes called the right of public access to the wilderness or the "right to roam".

In Scotland, Finland, Iceland, Norway, Sweden, Estonia, Latvia, Lithuania, Austria, Czech Republic and Switzerland, the freedom to roam takes the form of general public rights which are sometimes codified in law. The access is ancient in parts of Northern Europe and has been regarded as sufficiently basic that it was not formalised in law until modern times. However, the right usually does not include any substantial economic exploitation, such as hunting or logging, or disruptive activities, such as making fires and driving offroad vehicles.

In England and Wales public access rights apply only to certain categories of mainly uncultivated land.

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๐Ÿ”— Tobler's First Law of Geography

๐Ÿ”— Geography

The First Law of Geography, according to Waldo Tobler, is "everything is related to everything else, but near things are more related than distant things." This first law is the foundation of the fundamental concepts of spatial dependence and spatial autocorrelation and is utilized specifically for the inverse distance weighting method for spatial interpolation and to support the regionalized variable theory for kriging. It is a modern formulation of David Hume's principle of contiguity.

Tobler first presented his seminal idea during a meeting of the International Geographical Union's Commission on Qualitative Methods held in 1969 and later published by him in 1970. Though simple in its presentation, this idea is profound. Without it, "the full range of conditions anywhere on the Earth's surface could in principle be found packed within any small area. There would be no regions of approximately homogeneous conditions to be described by giving attributes to area objects. Topographic surfaces would vary chaotically, with slopes that were everywhere infinite, and the contours of such surfaces would be infinitely dense and contorted. Spatial analysis, and indeed life itself, would be impossible."

Less well known is his second law, which complements the first: "The phenomenon external to an area of interest affects what goes on inside".

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๐Ÿ”— Defenestrations of Prague

๐Ÿ”— Military history ๐Ÿ”— Military history/Early Modern warfare ๐Ÿ”— Military history/Medieval warfare ๐Ÿ”— Former countries ๐Ÿ”— Czech Republic ๐Ÿ”— Former countries/Holy Roman Empire

The Defenestrations of Prague (Czech: Praลพskรก defenestrace, German: Prager Fenstersturz, Latin: Defenestratio Pragensis) were three incidents in the history of Bohemia in which people were defenestrated (thrown out of a window). Though already existing in Middle French, the word defenestrate ("out of the window") is believed to have first been used in English in reference to the episodes in Prague in 1618 when the disgruntled Protestant estates threw two royal governors and their secretary out of a window of the Hradฤany Castle and wrote an extensive apologia explaining their action. In the Middle Ages and early modern times, defenestration was not uncommonโ€”the act carried elements of lynching and mob violence in the form of murder committed together.

The first governmental defenestration occurred in 1419, the second in 1483 and the third in 1618, although the term "Defenestration of Prague" more commonly refers to the third. Often, however, the 1483 event is not recognized as a "significant defenestration", which leads to some ambiguity when the 1618 defenestration is referred to as the "second Prague defenestration". The first and third defenestrations helped to trigger a prolonged religious conflict inside Bohemia (the Hussite Wars, 1st defenestration) or beyond (Thirty Years' War, 3rd defenestration), while the second helped establish a religious peace in the country for 31 years (Peace of Kutnรก Hora, 2nd defenestration).

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๐Ÿ”— The Mummy!

๐Ÿ”— Computing ๐Ÿ”— Africa ๐Ÿ”— Ancient Egypt ๐Ÿ”— Novels ๐Ÿ”— Novels/Science fiction ๐Ÿ”— Science Fiction ๐Ÿ”— Women writers ๐Ÿ”— Egypt

The Mummy! A Tale of the Twenty-Second Century is an 1827 three-volume novel written by Jane Webb (later Jane C. Loudon). It concerns the Egyptian mummy of Cheops, who is brought back to life in the year 2126. The novel describes a future filled with advanced technology, and was the first English-language story to feature a reanimated mummy.

After her father's death, making her an orphan at the age of 17, Webb found that:

on the winding up of his affairs that it would be necessary to do something for my support. I had written a strange, wild novel, called the Mummy, in which I had laid the scene in the twenty-second century, and attempted to predict the state of improvement to which this country might possibly arrive.

She may have drawn inspiration from the general fashion for anything pharaonic, inspired by the French researches during the Napoleonic invasion of Egypt; the 1821 public unwrappings of Egyptian mummies in a theatre near Piccadilly, which she may have attended as a girl; and, very likely, the 1818 novel by Mary Shelley, Frankenstein; or, The Modern Prometheus. As Shelley had written of Frankenstein's creation, "A mummy again endued with animation could not be so hideous as that wretch," which may have triggered her later concept. In any case, at many points she deals in greater clarity with elements from the earlier book such as the loathing for the much-desired object and the immediate arrest for crime and attempt to lie one's way out of it. However, unlike the Frankenstein monster, the hideous revived Cheops is not shuffling around dealing out horror and death, but giving canny advice on politics and life to those who befriend him. In some ways The Mummy! may be seen as her reaction to themes in Frankenstein: her mummy specifically says he is allowed life only by divine favour, rather than being indisputably vivified only by mortal science, and so on, as Hopkins' 2003 essay covers in detail.

Unlike many early science fiction works (Shelley's The Last Man, and The Reign of King George VI, 1900โ€“1925, written anonymously in 1763), Loudon did not portray the future as her own day with only political changes. She filled her world with foreseeable changes in technology, society, and even fashion. The hero, Edric Montague, lived in a peaceful and Catholic England under the rule of Queen Claudia. Her court ladies wear trousers and hair ornaments of controlled flame. Surgeons and lawyers may be steam-powered automatons. Air travel, by balloon, is commonplace. A kind of Internet is predicted in it. Besides trying to account for the revivification of the mummy in scientific termsโ€”galvanic shock rather than incantationsโ€”"she embodied ideas of scientific progress and discovery, that now read like prophecies" to those later in the 19th century. Many of the incidents in the book can be seen as satirical or humorous. Her social attitudes have resulted in this book being ranked among feminist novels.

The Mummy!: Or a Tale of the Twenty-Second Century was published anonymously in 1827 by Henry Colburn in three volumes, as was usual in that day so that each small volume could be easily carried around. It drew many favourable reviews, including one in 1829 in The Gardener's Magazine on the inventions proposed in it. In 1830, the 46-year-old reviewer, John Claudius Loudon, sought out the 22-year-old Webb, and they married the next year.

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๐Ÿ”— Gravity Probe B

๐Ÿ”— Spaceflight ๐Ÿ”— Physics ๐Ÿ”— Physics/relativity

Gravity Probe B (GP-B) was a satellite-based experiment to test two unverified predictions of general relativity: the geodetic effect and frame-dragging. This was to be accomplished by measuring, very precisely, tiny changes in the direction of spin of four gyroscopes contained in an Earth-orbiting satellite at 650ย km (400ย mi) altitude, crossing directly over the poles.

The satellite was launched on 20 April 2004 on a Delta II rocket. The spaceflight phase lasted until ; Its aim was to measure spacetime curvature near Earth, and thereby the stressโ€“energy tensor (which is related to the distribution and the motion of matter in space) in and near Earth. This provided a test of general relativity, gravitomagnetism and related models. The principal investigator was Francis Everitt.

Initial results confirmed the expected geodetic effect to an accuracy of about 1%. The expected frame-dragging effect was similar in magnitude to the current noise level (the noise being dominated by initially unmodeled effects due to nonuniform coatings on the gyroscopes). Work continued to model and account for these sources of error, thus permitting extraction of the frame-dragging signal. By , the frame-dragging effect had been confirmed to within 15% of the expected result, and the NASA report indicated that the geodetic effect was confirmed to be better than 0.5%.

In an article published in the journal Physical Review Letters in , the authors reported analysis of the data from all four gyroscopes results in a geodetic drift rate of โˆ’6601.8ยฑ18.3ย mas/yr and a frame-dragging drift rate of โˆ’37.2ยฑ7.2ย mas/yr, in good agreement with the general relativity predictions of โˆ’6606.1ยฑ0.28%ย mas/yr and โˆ’39.2ยฑ0.19%ย mas/yr, respectively.

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๐Ÿ”— Telescript programming language

๐Ÿ”— Computing

Telescript is an Agent-oriented programming language written by General Magic as part of the overall Magic Cap system. Telescript programs used a modified C-like syntax known as High Telescript and were compiled to a stack-based language called Low Telescript for execution. Low Telescript ran within virtual machine interpreters, or "Telescript engines", on host computers.

The basic model of Telescript is similar to Java, and differs primarily in where the applications would run. Java was modelled to make it possible to download Java applications onto any platform and run them locally. Telescript essentially reversed this, allowing end-user equipment with limited capabilities to upload Telescript programs to servers to allow them to take advantage of the server's capabilities. Telescript could even migrate a running program; the language included features to marshal a program's code and serialized state, transfer it to another Telescript engine (on a device or a server) to continue execution, and finally return to the originating client or server device to deliver its output.

General Magic had originally developed as a team within Apple Inc., and were spun off in 1990. When they began to generate some press buzz in 1992, Apple decided to enter the same market with their Newton tablet computer. General Magic were unable to find a niche within the market, and Telescript services were soon deprecated in favor of new products unrelated to mobile computing.

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