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🔗 Time

Solar time is a calculation of the passage of time based on the position of the Sun in the sky. The fundamental unit of solar time is the day. Two types of solar time are apparent solar time (sundial time) and mean solar time (clock time).

🔗 United States 🔗 Film 🔗 Library of Congress 🔗 Film/American cinema 🔗 United States/Film - American cinema 🔗 Film/Core

The Conversation is a 1974 American mystery thriller film written, produced and directed by Francis Ford Coppola and starring Gene Hackman with supporting roles by John Cazale, Allen Garfield, Cindy Williams, Frederic Forrest, Harrison Ford, Teri Garr and Robert Duvall.

The plot revolves around a surveillance expert and the moral dilemma he faces when his recordings reveal a potential murder. Coppola cited the 1966 film Blowup as a key influence. However, since the film was released to theaters just a few months before Richard Nixon resigned as President, he felt that audiences interpreted the film to be a reaction to the Watergate scandal. The Conversation has won critical acclaim and multiple accolades, including the Grand Prix du Festival International du Film, the highest honor at the 1974 Cannes Film Festival. It was nominated for three Academy Awards in 1974 and lost Best Picture to The Godfather Part II, another Francis Ford Coppola film. In 1995, it was selected for preservation in the National Film Registry by the Library of Congress as being "culturally, historically, or aesthetically significant".

🔗 Architecture 🔗 Firearms 🔗 Metalworking

A shot tower is a tower designed for the production of small diameter shot balls by freefall of molten lead, which is then caught in a water basin. The shot is primarily used for projectiles in shotguns, and also for ballast, radiation shielding and other applications where small lead balls are useful.

🔗 Biography 🔗 Economics 🔗 Biography/science and academia 🔗 United Kingdom 🔗 Virginia 🔗 Chicago 🔗 Virginia/Albemarle County

Ronald Harry Coase (; 29 December 1910 – 2 September 2013) was a British economist and author. He was the Clifton R. Musser Professor of Economics at the University of Chicago Law School, where he arrived in 1964 and remained for the rest of his life. He received the Nobel Memorial Prize in Economic Sciences in 1991.

Coase, who believed economists should study real markets and not theoretical ones, established the case for the corporation as a means to pay the costs of operating a marketplace. Coase is best known for two articles in particular: "The Nature of the Firm" (1937), which introduces the concept of transaction costs to explain the nature and limits of firms; and "The Problem of Social Cost" (1960), which suggests that well-defined property rights could overcome the problems of externalities (see Coase theorem). Additionally, Coase's transaction costs approach is currently influential in modern organizational economics, where it was reintroduced by Oliver E. Williamson.

🔗 Animals

Tardigrades (), known colloquially as water bears or moss piglets, are a phylum of water-dwelling eight-legged segmented micro-animals. They were first described by the German zoologist Johann August Ephraim Goeze in 1773, who called them little water bears. In 1777, the Italian biologist Lazzaro Spallanzani named them Tardigrada, which means "slow steppers".

They have been found everywhere, from mountaintops to the deep sea and mud volcanoes, and from tropical rainforests to the Antarctic. Tardigrades are among the most resilient animals known, with individual species able to survive extreme conditions—such as exposure to extreme temperatures, extreme pressures (both high and low), air deprivation, radiation, dehydration, and starvation—that would quickly kill most other known forms of life. Tardigrades have survived exposure to outer space. About 1,300 known species form the phylum Tardigrada, a part of the superphylum Ecdysozoa. The earliest known true members of the group are known from Cretaceous amber in North America, but are essentially modern forms, and therefore likely have a significantly earlier origin, as they diverged from their closest relatives in the Cambrian, over 500 million years ago.

Tardigrades are usually about 0.5 mm (0.02 in) long when fully grown. They are short and plump, with four pairs of legs, each ending in claws (usually four to eight) or sucking disks. Tardigrades are prevalent in mosses and lichens and feed on plant cells, algae, and small invertebrates. When collected, they may be viewed under a low-power microscope, making them accessible to students and amateur scientists.

🔗 Philosophy 🔗 Philosophy/Logic 🔗 Business 🔗 Politics 🔗 Psychology 🔗 Politics/Corporatism

Groupthink is a psychological phenomenon that occurs within a group of people in which the desire for harmony or conformity in the group results in an irrational or dysfunctional decision-making outcome. Cohesiveness, or the desire for cohesiveness, in a group may produce a tendency among its members to agree at all costs. This causes the group to minimize conflict and reach a consensus decision without critical evaluation.

Groupthink requires individuals to avoid raising controversial issues or alternative solutions, and there is loss of individual creativity, uniqueness and independent thinking. The dysfunctional group dynamics of the "ingroup" produces an "illusion of invulnerability" (an inflated certainty that the right decision has been made). Thus the "ingroup" significantly overrates its own abilities in decision-making and significantly underrates the abilities of its opponents (the "outgroup"). Furthermore, groupthink can produce dehumanizing actions against the "outgroup". Members of a group can often feel peer pressure to "go along with the crowd" in fear of rocking the boat or of what them speaking up will do to the overall to how their teammates perceive them. Group interactions tend to favor, clear and harmonious agreements and it can be a cause for concern when little to no new innovations or arguments for better policies, outcomes and structures are called to question. (McLeod). Groupthink can often be referred to as a group of “yes men” because group activities and group projects in general make it extremely easy to pass on not offering constructive opinions.

Some methods that have been used to counteract group think in the past is selecting teams from more diverse backgrounds, and even mixing men and women for groups (Kamalnath). Groupthink can be considered by many to be a detriment to companies, organizations and in any work situations. Most positions that are senior level need individuals to be independent in their thinking. There is a positive correlation found between outstanding executives and decisiveness (Kelman). Groupthink also prohibits an organization from moving forward and innovating if no one ever speaks up and says something could be done differently.

Antecedent factors such as group cohesiveness, faulty group structure, and situational context (e.g., community panic) play into the likelihood of whether or not groupthink will impact the decision-making process.

Groupthink is a construct of social psychology, but has an extensive reach and influences literature in the fields of communication studies, political science, management, and organizational theory, as well as important aspects of deviant religious cult behaviour.

Groupthink is sometimes stated to occur (more broadly) within natural groups within the community, for example to explain the lifelong different mindsets of those with differing political views (such as "conservatism" and "liberalism" in the U.S. political context ) or the purported benefits of team work vs. work conducted in solitude. However, this conformity of viewpoints within a group does not mainly involve deliberate group decision-making, and might be better explained by the collective confirmation bias of the individual members of the group.

Most of the initial research on groupthink was conducted by Irving Janis, a research psychologist from Yale University. Janis published an influential book in 1972, which was revised in 1982. Janis used the Bay of Pigs disaster (the failed invasion of Castro's Cuba in 1961) and the Japanese attack on Pearl Harbor in 1941 as his two prime case studies. Later studies have evaluated and reformulated his groupthink model.

🔗 United States/U.S. Government 🔗 United States 🔗 Biography 🔗 Computing 🔗 Military history 🔗 Military history/North American military history 🔗 United States/Military history - U.S. military history 🔗 Military history/Military science, technology, and theory 🔗 New York City 🔗 Women scientists 🔗 Biography/science and academia 🔗 Women's History 🔗 Military history/Military biography 🔗 Biography/military biography 🔗 Software 🔗 Software/Computing 🔗 Military history/Maritime warfare 🔗 Pritzker Military Library

Grace Brewster Murray Hopper (née Murray December 9, 1906 – January 1, 1992) was an American computer scientist and United States Navy rear admiral. One of the first programmers of the Harvard Mark I computer, she was a pioneer of computer programming who invented one of the first linkers. She popularized the idea of machine-independent programming languages, which led to the development of COBOL, an early high-level programming language still in use today.

Prior to joining the Navy, Hopper earned a Ph.D. in mathematics from Yale University and was a professor of mathematics at Vassar College. Hopper attempted to enlist in the Navy during World War II but was rejected because she was 34 years old. She instead joined the Navy Reserves. Hopper began her computing career in 1944 when she worked on the Harvard Mark I team led by Howard H. Aiken. In 1949, she joined the Eckert–Mauchly Computer Corporation and was part of the team that developed the UNIVAC I computer. At Eckert–Mauchly she began developing the compiler. She believed that a programming language based on English was possible. Her compiler converted English terms into machine code understood by computers. By 1952, Hopper had finished her program linker (originally called a compiler), which was written for the A-0 System. During her wartime service, she co-authored three papers based on her work on the Harvard Mark 1.

In 1954, Eckert–Mauchly chose Hopper to lead their department for automatic programming, and she led the release of some of the first compiled languages like FLOW-MATIC. In 1959, she participated in the CODASYL consortium, which consulted Hopper to guide them in creating a machine-independent programming language. This led to the COBOL language, which was inspired by her idea of a language being based on English words. In 1966, she retired from the Naval Reserve, but in 1967 the Navy recalled her to active duty. She retired from the Navy in 1986 and found work as a consultant for the Digital Equipment Corporation, sharing her computing experiences.

The U.S. Navy Arleigh Burke-class guided-missile destroyer USS Hopper was named for her, as was the Cray XE6 "Hopper" supercomputer at NERSC. During her lifetime, Hopper was awarded 40 honorary degrees from universities across the world. A college at Yale University was renamed in her honor. In 1991, she received the National Medal of Technology. On November 22, 2016, she was posthumously awarded the Presidential Medal of Freedom by President Barack Obama.

🔗 Cryptography 🔗 Cryptography/Computer science

PGPfone was a secure voice telephony system developed by Philip Zimmermann in 1995. The PGPfone protocol had little in common with Zimmermann's popular PGP email encryption package, except for the use of the name. It used ephemeral Diffie-Hellman protocol to establish a session key, which was then used to encrypt the stream of voice packets. The two parties compared a short authentication string to detect a Man-in-the-middle attack, which is the most common method of wiretapping secure phones of this type. PGPfone could be used point-to-point (with two modems) over the public switched telephone network, or over the Internet as an early Voice over IP system.

In 1996, there were no protocol standards for Voice over IP. Ten years later, Zimmermann released the successor to PGPfone, Zfone and ZRTP, a newer and secure VoIP protocol based on modern VoIP standards. Zfone builds on the ideas of PGPfone.

According to the MIT PGPfone web page, "MIT is no longer distributing PGPfone. Given that the software has not been maintained since 1997, we doubt it would run on most modern systems."

🔗 Medicine 🔗 Psychology 🔗 Physiology

Biphasic sleep (or diphasic, bimodal or bifurcated sleep) is the practice of sleeping during two periods over the course of 24 hours, while polyphasic sleep refers to sleeping multiple times – usually more than two. Each of these is in contrast to monophasic sleep, which is one period of sleep within 24 hours. Segmented sleep and divided sleep may refer to polyphasic or biphasic sleep, but may also refer to interrupted sleep, where the sleep has one or several shorter periods of wakefulness. A common form of biphasic or polyphasic sleep includes a nap, which is a short period of sleep, typically taken between the hours of 9 am and 9 pm as an adjunct to the usual nocturnal sleep period. Nowadays, the definition of polyphasic sleep is any sleep schedule with at least two sleeps per day, to distinguish it from monophasic sleep, which only has one sleep per day.

The term polyphasic sleep was first used in the early 20th century by psychologist J. S. Szymanski, who observed daily fluctuations in activity patterns (see Stampi 1992). It does not imply any particular sleep schedule. The circadian rhythm disorder known as irregular sleep-wake syndrome is an example of polyphasic sleep in humans. Polyphasic sleep is common in many animals, and is believed to be the ancestral sleep state for mammals, although simians are monophasic.

The term polyphasic sleep is also used by an online community that experiments with alternative sleeping schedules to achieve more time awake each day. However, researchers such as Piotr Woźniak warn that such forms of sleep deprivation are not healthy. While many claim that polyphasic sleep was widely used by some polymaths and prominent people such as Leonardo da Vinci, Napoleon, and Nikola Tesla, there are few reliable sources supporting that view.