Summary

HandWiki is the world's largest wiki-style encyclopedia dedicated to science, technology and computing. It allows you to create and edit articles as long as you have external citations and login account. In addition, this is a content management environment that can be used for collaborative editing of original scholarly content, such as books, manuals, monographs and tutorials.

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Six-factor Model of Psychological Well-being
The Six-factor Model of Psychological Well-being is a theory developed by Carol Ryff which determines six factors which contribute to an individual's psychological well-being, contentment, and happiness. Psychological well-being consists of positive relationships with others, personal mastery, autonomy, a feeling of purpose and meaning in life, and personal growth and development. Psychological well-being is attained by achieving a state of balance affected by both challenging and rewarding life events.
  • 11.5K
  • 20 Oct 2022
Topic Review
Dilophosauridae
Dilophosauridae is a family of medium to large sized theropod dinosaurs. The name Dilophosauridae is derived from Greek, with “di-” meaning “two,” “lophos” meaning “crest,” “sauros” meaning “lizard,” and “-idae” meaning “family”. While the name suggests that all dilophosaurids have two crests, this is not applicable to all dilophosaurids. The Dilophosauridae is anchored by its type genus, Dilophosaurus, and therefore the name comes from the distinctive two crests of the genus.
  • 4.9K
  • 24 Oct 2022
Topic Review
Wildcard DNS Record
A wildcard DNS record is a record in a DNS zone that will match requests for non-existent domain names. A wildcard DNS record is specified by using a * as the leftmost label (part) of a domain name, e.g. *.example.com. The exact rules for when a wild card will match are specified in RFC 1034, but the rules are neither intuitive nor clearly specified. This has resulted in incompatible implementations and unexpected results when they are used.
  • 685
  • 20 Oct 2022
Topic Review
Semaphore Line
A semaphore telegraph is a system of conveying information by means of visual signals, using towers with pivoting shutters, also known as blades or paddles. Information is encoded by the position of the mechanical elements; it is read when the shutter is in a fixed position. The most widely used system was invented in 1792 in France by Claude Chappe, and was popular in the late eighteenth to early nineteenth centuries. Lines of relay towers with a semaphore rig at the top were built within line-of-sight of each other, at separations of 5 to 20 miles. Operators at each tower would watch the neighboring tower through a spyglass, and when the semaphore arms began to move spelling out a message. They would pass the message on to the next tower. This system was much faster than post riders for conveying a message over long distances, and also had cheaper long-term operating costs, once constructed. Semaphore lines were a precursor of the electrical telegraph, which would replace them half a century later, and would also be cheaper, faster, and more private. The line-of-sight distance between relay stations was limited by geography and weather, and prevented the optical telegraph from crossing wide expanses of water, unless a convenient island could be used for a relay station. Modern derivatives of the semaphore system include flag semaphore (a flag relay system) and the heliograph (optical telegraphy using mirror-directed sunlight reflections).
  • 3.7K
  • 20 Oct 2022
Topic Review
Health Star Rating System
The Health Star Rating System (HSR) is an Australian Government initiative that assigns health ratings to packaged foods and beverages. The Health Star Rating System was established in 2014 as a preventative measure in slowing or reversing the rate of overweight Australians. According to the Australian Bureau of Statistics, over 63% of Australian adults were classified either overweight or obese at that time. The purpose for the Health Star Rating is to provide a visual comparison of like for like products, to assist consumers into distinguishing and choosing the healthier options. It was designed to target time-deprived working adults as well as parents and children who were less likely to check how healthy each individual product was, through examination of the nutritional facts label on the back of products. Ratings scale by half star increments between half a star up to five stars, with the higher the rating, the healthier the product. These scores are determined through the use of the Health Star Rating Calculator, which was created by the federal and state governments in collaboration with leading health industry consumer groups and expert nutritionists. The calculator uses nutritional information such as total sugar, sodium, energy and other variants to obtain a rating for the product. Points are added for "healthy" nutrients such as fibres, proteins and vegetable matter whilst points are deducted for "unhealthy" nutrients; nutrients that have been scientifically linked to chronic health disease, such as fats and sugars. There are two types of HSR logos that companies can add to their packaging, one which simply displays the rating and another which depicts the rating along with some of the key nutritional categories. The Health Star Rating has received criticism over the effectiveness of the calculator and how some companies have potentially manipulated its use. The system has undergone consistent internal monitoring including a two-year review and is currently undertaking a five-year review. An early preview of the five year report was made available for public viewing from February 2019. The Australian Government has stated that it has closely followed external input and advice from independent journals and papers to continually improve on the system and resolve problems as they arise.
  • 1.8K
  • 20 Oct 2022
Topic Review
Kepler (Spacecraft)
Kepler is a space observatory launched by NASA to discover Earth-size planets orbiting other stars. Named after astronomer Johannes Kepler, the spacecraft was launched on March 7, 2009, into an Earth-trailing heliocentric orbit. The principal investigator was William J. Borucki. Designed to survey a portion of our region of the Milky Way to discover Earth-size exoplanets in or near habitable zones and estimate how many of the billions of stars in the Milky Way have such planets, Kepler's sole scientific instrument is a photometer that continually monitors the brightness of approx 150,000 main sequence stars in a fixed field of view. These data are transmitted to Earth, then analyzed to detect periodic dimming caused by exoplanets that cross in front of their host star. Kepler is part of NASA's Discovery Program of relatively low-cost, focused primary science missions. The telescope's construction and initial operation were managed by NASA's Jet Propulsion Laboratory, with Ball Aerospace responsible for developing the Kepler flight system. The Ames Research Center is responsible for the ground system development, mission operations since December 2009, and scientific data analysis. The initial planned lifetime was 3.5 years, but greater-than-expected noise in the data, from both the stars and the spacecraft, meant additional time was needed to fulfill all mission goals. Initially, in 2012, the mission was expected to be extended until 2016, but on July 14, 2012, one of the spacecraft's four reaction wheels used for pointing the spacecraft stopped turning, and completing the mission would only be possible if all other reaction wheels remained reliable. Then, on May 11, 2013, a second reaction wheel failed, disabling the collection of science data and threatening the continuation of the mission. On August 15, 2013, NASA announced that they had given up trying to fix the two failed reaction wheels. This meant the current mission needed to be modified, but it did not necessarily mean the end of planet hunting. NASA had asked the space science community to propose alternative mission plans "potentially including an exoplanet search, using the remaining two good reaction wheels and thrusters". On November 18, 2013, the K2 "Second Light" proposal was reported. This would include utilizing the disabled Kepler in a way that could detect habitable planets around smaller, dimmer red dwarfs. On May 16, 2014, NASA announced the approval of the K2 extension. (As of January 2015), Kepler and its follow-up observations had found 1,013 confirmed exoplanets in about 440 star systems, along with a further 3,199 unconfirmed planet candidates.[upper-alpha 2] Four planets have been confirmed through Kepler's K2 mission. In November 2013, astronomers estimated, based on Kepler space mission data, that there could be as many as 40 billion rocky, Earth-size exoplanets orbiting in the habitable zones of Sun-like stars and red dwarfs within the Milky Way. It is estimated that 11 billion of these planets may be orbiting Sun-like stars. The nearest such planet may be 3.7 parsecs (12 ly) away, according to the scientists. On January 6, 2015, NASA announced the 1,000th confirmed exoplanet discovered by the Kepler Space Telescope. Four of the newly confirmed exoplanets were found to orbit within habitable zones of their related stars: three of the four, Kepler-438b, Kepler-442b and Kepler-452b, are almost Earth-size and likely rocky; the fourth, Kepler-440b, is a super-Earth. On May 10, 2016, NASA verified 1,284 new exoplanets found by Kepler, the single largest finding of planets to date. Kepler data has also helped scientists observe and understand supernovae; measurements were collected every half-hour so the light curves were especially useful for studying these types of astronomical events.
  • 4.4K
  • 20 Oct 2022
Topic Review
Testing Effect
The testing effect is the finding that long-term memory is often increased when some of the learning period is devoted to retrieving the to-be-remembered information. The effect is also sometimes referred to as retrieval practice, practice testing, or test-enhanced learning. Retrieval practice may be the best way to refer to the testing effect because the benefits of retrieval-related testing are not limited to tests. It can be more broad, including tools like flash cards and quizzes. The testing effect on memory should be distinguished from more general practice effects, defined in the APA Dictionary of Psychology (2007) as "any change or improvement that results from practice or repetition of task items or activities." The term testing effect is also sometimes used in a more general sense; The Oxford Dictionary of Psychology (2003) defines a testing effect as "any effect of taking tests on the respondents, a typical example being test sophistication." Whereas psychologists who develop tests for personality and intelligence want to avoid practice effects, cognitive psychologists working with educators have begun to understand how to take advantage of tests—not as an assessment tool, but as a teaching/learning tool. It is useful for people to test their knowledge of the to-be-remembered material during the learning process, instead of only reading or otherwise passively studying the material. For example, a student can use flashcards to self-test and receive feedback as they study. The testing effect provides a larger benefit to long-term memory when the tested material is difficult enough to require effort, the rate of retrieval success is high, and feedback with correct answers is given after testing. The testing effect is activated by active recall.
  • 11.8K
  • 20 Oct 2022
Topic Review
Croquet OS
Croquet OS is a web-based operating system for creating three-dimensional apps with multi-user functionalities that run simultaneously on any device. Croquet can be used for communication, online gaming environments such as massively multiplayer online role-playing games (MMORPGs), 3D wikis, virtual learning and problem solving environments, privately maintained or interconnected multi-user virtual environments, and more advanced functions such as highly scalable collaborative data visualization, resource sharing, and synchronous computation among multiple users.
  • 700
  • 20 Oct 2022
Topic Review
Deinonychosauria
Deinonychosauria is a probable stem-bird clade of maniraptoran dinosaurs that lived from the Late Jurassic to the Late Cretaceous periods. Fossils have been found across the globe in North America, Europe, Africa, Japan , China , Mongolia, Manchuria, Madagascar , Argentina , and Antarctica, with fossilized teeth giving credence to the possibility that they inhabited Australia as well. This group of dinosaurs are known for their sickle-shaped toe claws and features in the shoulder bones.
  • 1.8K
  • 24 Oct 2022
Topic Review
Judgment of Solomon
The Judgment of Solomon is a story from the Hebrew Bible in which King Solomon of Israel ruled between two women both claiming to be the mother of a child. Solomon revealed their true feelings and relationship to the child by suggesting to cut the baby in two, with each woman to receive half. With this strategy, he was able to discern the non-mother as the woman who entirely approved of this proposal, while the actual mother begged that the sword might be sheathed and the child committed to the care of her rival. Some consider this approach to justice an archetypal example of an impartial judge displaying wisdom in making a ruling.
  • 79.0K
  • 24 Oct 2022
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