Have a deep view into what people are curious about.

🔗 Mathematics

The Cox–Zucker machine is an algorithm created by David A. Cox and Steven Zucker. This algorithm determines if a given set of sections provides a basis (up to torsion) for the Mordell–Weil group of an elliptic surface E → S where S is isomorphic to the projective line.

The algorithm was first published in the 1979 paper "Intersection numbers of sections of elliptic surfaces" by Cox and Zucker, and it was later named the "Cox–Zucker machine" by Charles Schwartz in 1984. The name is a homophone for an obscenity, and this was a deliberate move by Cox and Zucker, who conceived of the idea of coauthoring a paper as graduate students at Princeton for the express purpose of enabling this joke, a joke they followed through on while professors at Rutgers five years later. As Cox explained in a memorial tribute to Zucker in Notices of the American Mathematical Society in 2021: "A few weeks after we met, we realized that we had to write a joint paper because the combination of our last names, in the usual alphabetical order, is remarkably obscene."

Graffiti is an essentially single-stroke shorthand handwriting recognition system used in PDAs based on the Palm OS. Graffiti was originally written by Palm, Inc. as the recognition system for GEOS-based devices such as HP's OmniGo 100 and 120 or the Magic Cap-line and was available as an alternate recognition system for the Apple Newton MessagePad, when NewtonOS 1.0 could not recognize handwriting very well. Graffiti also runs on the Windows Mobile platform, where it is called "Block Recognizer", and on the Symbian UIQ platform as the default recognizer and was available for Casio's Zoomer PDA.

The software is based primarily on a neography of upper-case characters that can be drawn blindly with a stylus on a touch-sensitive panel. Since the user typically cannot see the character as it is being drawn, complexities have been removed from four of the most difficult letters. "A" "F", "K" and "T" all are drawn without any need to match up a cross-stroke.

Some letters can be drawn with strokes other than the "official" ones. Two examples of these alternative strokes are the letters "V" (drawn the same only from right to left) and "X" (drawn the same as the letter "K" except reversed from right to left). These alternative strokes are frequently recognized with greater reliability.

🔗 United States 🔗 Aviation 🔗 Spaceflight 🔗 Rocketry

The Space Transportation System (STS), also known internally to NASA as the Integrated Program Plan (IPP), was a proposed system of reusable manned space vehicles envisioned in 1969 to support extended operations beyond the Apollo program. (NASA appropriated the name for its Space Shuttle Program, the only component of the proposal to survive Congressional funding approval). The purpose of the system was twofold: to reduce the cost of spaceflight by replacing the current method of launching capsules on expendable rockets with reusable spacecraft; and to support ambitious follow-on programs including permanent orbiting space stations around the Earth and Moon, and a human landing mission to Mars.

In February 1969, President Richard Nixon appointed a Space Task Group headed by Vice President Spiro Agnew to recommend human space projects beyond Apollo. The group responded in September with the outline of the STS, and three different program levels of effort culminating with a human Mars landing by 1983 at the earliest, and by the end of the twentieth century at the latest. The system's major components consisted of:

• A permanent space station module designed for 6 to 12 occupants, in a 270-nautical-mile (500 km) low Earth orbit, and as a permanent lunar orbit station. Modules could be combined in Earth orbit to create a 50 to 100 person permanent station.
• A chemically fueled Earth-to-station shuttle.
• A chemically fueled space tug to move crew and equipment between Earth orbits as high as geosynchronous orbit, which could be adapted as a lunar orbit-to-surface shuttle.
• A nuclear-powered ferry using the NERVA engine, to move crew, spacecraft and supplies between low Earth orbit and lunar orbit, geosynchronous orbit, or to other planets in the solar system.

The tug and ferry vehicles would be of a modular design, allowing them to be clustered and/or staged for large payloads or interplanetary missions. The system would be supported by permanent Earth and lunar orbital propellant depots. The Saturn V might still have been used as a heavy lift launch vehicle for the nuclear ferry and space station modules. A special "Mars Excursion Module" would be the only remaining vehicle necessary for a human Mars landing.

As Apollo accomplished its objective of landing the first men on the Moon, political support for further manned space activities began to wane, which was reflected in unwillingness of the Congress to provide funding for most of these extended activities. Based on this, Nixon rejected all parts of the program except the Space Shuttle, which inherited the STS name. As funded, the Shuttle was greatly scaled back from its planned degree of reusability, and deferred in time. The Shuttle first flew in 1981, and was retired in 2011.

A second part of the system, Space Station Freedom, was approved in the early 1980s and announced in 1984 by president Ronald Reagan. However, this also became politically unviable by 1993, and was replaced with the International Space Station (ISS), with substantial contribution by Russia. The ISS was completed in 2010.

🔗 Computing 🔗 Computing/Networking

Intelink is a group of secure intranets used by the United States Intelligence Community. The first Intelink network was established in 1994 to take advantage of Internet technologies (though not connected to the public Internet) and services to promote intelligence dissemination and business workflow. Since then it has become an essential capability for the US intelligence community and its partners to share information, collaborate across agencies, and conduct business. Intelink refers to the web environment on protected top secret, secret, and unclassified networks. One of the key features of Intelink is Intellipedia, an online system for collaborative data sharing based on MediaWiki. Intelink uses WordPress as the basis of its blogging service.

🔗 Biography 🔗 Climate change 🔗 Women 🔗 Guild of Copy Editors 🔗 Biography/politics and government 🔗 Sweden 🔗 Autism

Greta Tintin Eleonora Ernman Thunberg (Swedish: [ˈɡrêːta ˈtʉ̂ːnbærj] (listen); born 3 January 2003) is a Swedish environmental activist who has gained international recognition for promoting the view that humanity is facing an existential crisis arising from climate change. Thunberg is known for her youth and her straightforward speaking manner, both in public and to political leaders and assemblies, in which she criticizes world leaders for their failure to take sufficient action to address the climate crisis.

Thunberg's activism started after convincing her parents to adopt several lifestyle choices to reduce their own carbon footprint. In August 2018, at age 15, she started spending her school days outside the Swedish parliament to call for stronger action on climate change by holding up a sign reading Skolstrejk för klimatet (School strike for climate). Soon, other students engaged in similar protests in their own communities. Together, they organised a school climate strike movement under the name Fridays for Future. After Thunberg addressed the 2018 United Nations Climate Change Conference, student strikes took place every week somewhere in the world. In 2019, there were multiple coordinated multi-city protests involving over a million students each. To avoid flying, Thunberg sailed to North America where she attended the 2019 UN Climate Action Summit. Her speech there, in which she exclaimed "how dare you", was widely taken up by the press and incorporated into music.

Her sudden rise to world fame has made her both a leader and a target for critics. Her influence on the world stage has been described by The Guardian and other newspapers as the "Greta effect". She has received numerous honours and awards including: honorary Fellowship of the Royal Scottish Geographical Society; Time magazine's 100 most influential people and the youngest Time Person of the Year; inclusion in the Forbes list of The World's 100 Most Powerful Women (2019) and two consecutive nominations for the Nobel Peace Prize (2019 and 2020).

🔗 United States 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 United States/American Old West 🔗 Military history/Military logistics and medicine 🔗 Military history/American Civil War

The United States Camel Corps was a mid-19th-century experiment by the United States Army in using camels as pack animals in the Southwestern United States. While the camels proved to be hardy and well suited to travel through the region, the Army declined to adopt them for military use. The Civil War interfered with the experiment and it was eventually abandoned; the animals were sold at auction.

🔗 Russia 🔗 Dogs 🔗 Russia/science and education in Russia 🔗 Genetics

The domesticated silver fox is a form of the silver fox that has been to some extent domesticated under laboratory conditions. The silver fox is a melanistic form of the wild red fox. Domesticated silver foxes are the result of an experiment designed to demonstrate the power of selective breeding to transform species, as described by Charles Darwin in On the Origin of Species. The experiment at the Institute of Cytology and Genetics in Novosibirsk, Siberia explored whether selection for behaviour rather than morphology may have been the process that had produced dogs from wolves, by recording the changes in foxes when in each generation only the most tame foxes were allowed to breed. Many of the descendant foxes became both tamer and more dog-like in morphology, including displaying mottled or spotted coloured fur.

In 2019, an international research team questioned the conclusion that this experiment had provided strong support for the validity of domestication syndrome. They did conclude that it remains "a resource for investigation of the genomics and biology of behavior".

🔗 Biography

Joseph P. Nacchio (born June 22, 1949 in Brooklyn, New York) is an American executive who was chairman of the board and chief executive officer of Qwest Communications International from 1997 to 2002. Nacchio was convicted of insider trading during his time heading Qwest. He claimed in court, with documentation, that his was the only company to demand legal authority for surreptitious mass surveillance demanded by the NSA which began prior to the 11 September 2001 attacks.

He was convicted of 19 counts of insider trading in Qwest stock on April 19, 2007 – charges his defense team claimed were U.S. government retaliation for his refusal to give customer data to the National Security Agency in February, 2001. This defense was not admissible in court because the U.S. Department of Justice filed an in limine motion, which is often used in national security cases, to exclude information which may reveal state secrets. Information from the Classified Information Procedures Act hearings in Nacchio's case was likewise ruled inadmissible.

On July 27, 2007, he was sentenced to six years in federal prison, and after appeals failed he reported to Federal Correctional Institution, Schuylkill in Schuylkill County, Pennsylvania on April 14, 2009 to serve his sentence. Nacchio finished serving his sentence on September 20, 2013.

🔗 Energy 🔗 Engineering

A heat pipe is a heat-transfer device that employs phase transition to transfer heat between two solid interfaces.

At the hot interface of a heat pipe, a volatile liquid in contact with a thermally conductive solid surface turns into a vapor by absorbing heat from that surface. The vapor then travels along the heat pipe to the cold interface and condenses back into a liquid, releasing the latent heat. The liquid then returns to the hot interface through capillary action, centrifugal force, or gravity and the cycle repeats.

Due to the very high heat transfer coefficients for boiling and condensation, heat pipes are highly effective thermal conductors. The effective thermal conductivity varies with heat pipe length and can approach 100 kW/(m⋅K) for long heat pipes, in comparison with approximately 0.4 kW/(m⋅K) for copper.

Modern CPU heat pipes are typically made of copper and use water as the working fluid. They are common in many consumer electronics like desktops, laptops, tablets, and high-end smartphones.

🔗 Statistics

The Erlang distribution is a two-parameter family of continuous probability distributions with support ${\displaystyle x\in [0,\infty )}$. The two parameters are:

• a positive integer ${\displaystyle k,}$ the "shape", and
• a positive real number ${\displaystyle \lambda ,}$ the "rate". The "scale", ${\displaystyle \mu ,}$ the reciprocal of the rate, is sometimes used instead.

The Erlang distribution with shape parameter ${\displaystyle k=1}$ simplifies to the exponential distribution. It is a special case of the gamma distribution. It is the distribution of a sum of ${\displaystyle k}$ independent exponential variables with mean ${\displaystyle 1/\lambda }$ each.

The Erlang distribution was developed by A. K. Erlang to examine the number of telephone calls which might be made at the same time to the operators of the switching stations. This work on telephone traffic engineering has been expanded to consider waiting times in queueing systems in general. The distribution is also used in the field of stochastic processes.