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🔗 Euthanasia Coaster

🔗 Death 🔗 Lithuania 🔗 Amusement Parks 🔗 Amusement Parks/Roller Coasters

The Euthanasia Coaster is a hypothetical steel roller coaster designed to kill its passengers. In 2010, it was designed and made into a scale model by Lithuanian artist Julijonas Urbonas, a PhD candidate at the Royal College of Art in London. Urbonas, who has worked at an amusement park, stated that the goal of his concept roller coaster is to take lives "with elegance and euphoria". As for practical applications of his design, Urbonas mentioned "euthanasia" or "execution". John Allen, who served as president of the Philadelphia Toboggan Company, inspired Urbonas with his description of the "ultimate" roller coaster as one that "sends out 24 people and they all come back dead".

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🔗 Mode 2

🔗 History of Science

A knowledge production mode is a term from the sociology of science which refers to the way (scientific) knowledge is produced. So far, three modes have been conceptualized. Mode 1 production of knowledge is knowledge production motivated by scientific knowledge alone (basic research) which is not primarily concerned by the applicability of its findings. Mode 1 is founded on a conceptualization of science as separated into discrete disciplines (e.g., a biologist does not bother about chemistry). Mode 2 was coined in 1994 in juxtaposition to Mode 1 by Michael Gibbons, Camille Limoges, Helga Nowotny, Simon Schwartzman, Peter Scott and Martin Trow. In Mode 2, multidisciplinary teams are brought together for short periods of time to work on specific problems in the real world for knowledge production (applied research) in the knowledge society. Mode 2 can be explained by the way research funds are distributed among scientists and how scientists focus on obtaining these funds in terms of five basic features: 1) knowledge produced in the context of application; (2) transdisciplinarity; (3) heterogeneity and organizational diversity; (4) social accountability and reflexivity; (5) and quality control. Subsequently, Carayannis and Campbell described a Mode 3 knowledge in 2006.

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🔗 Ant Colony Optimization Algorithms

🔗 Computer science 🔗 Systems 🔗 Systems/Scientific modeling

In computer science and operations research, the ant colony optimization algorithm (ACO) is a probabilistic technique for solving computational problems which can be reduced to finding good paths through graphs. Artificial Ants stand for multi-agent methods inspired by the behavior of real ants. The pheromone-based communication of biological ants is often the predominant paradigm used. Combinations of Artificial Ants and local search algorithms have become a method of choice for numerous optimization tasks involving some sort of graph, e.g., vehicle routing and internet routing. The burgeoning activity in this field has led to conferences dedicated solely to Artificial Ants, and to numerous commercial applications by specialized companies such as AntOptima.

As an example, Ant colony optimization is a class of optimization algorithms modeled on the actions of an ant colony. Artificial 'ants' (e.g. simulation agents) locate optimal solutions by moving through a parameter space representing all possible solutions. Real ants lay down pheromones directing each other to resources while exploring their environment. The simulated 'ants' similarly record their positions and the quality of their solutions, so that in later simulation iterations more ants locate better solutions. One variation on this approach is the bees algorithm, which is more analogous to the foraging patterns of the honey bee, another social insect.

This algorithm is a member of the ant colony algorithms family, in swarm intelligence methods, and it constitutes some metaheuristic optimizations. Initially proposed by Marco Dorigo in 1992 in his PhD thesis, the first algorithm was aiming to search for an optimal path in a graph, based on the behavior of ants seeking a path between their colony and a source of food. The original idea has since diversified to solve a wider class of numerical problems, and as a result, several problems have emerged, drawing on various aspects of the behavior of ants. From a broader perspective, ACO performs a model-based search and shares some similarities with estimation of distribution algorithms.

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🔗 Technical debt

🔗 Computing

Technical debt (also known as design debt or code debt, but can be also related to other technical endeavors) is a concept in software development that reflects the implied cost of additional rework caused by choosing an easy (limited) solution now instead of using a better approach that would take longer.

As with monetary debt, if technical debt is not repaid, it can accumulate 'interest', making it harder to implement changes. Unaddressed technical debt increases software entropy. Technical debt is not necessarily a bad thing, and sometimes (e.g., as a proof-of-concept) is required to move projects forward. On the other hand, some experts claim that the "technical debt" metaphor tends to minimize the impact, which results in insufficient prioritization of the necessary work to correct it.

As a change is started on a codebase, there is often the need to make other coordinated changes in other parts of the codebase or documentation. Changes required that are not completed are considered debt, and until paid, will incur interest on top of interest, making it cumbersome to build a project. Although the term is used in software development primarily, it can also be applied to other professions.

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🔗 Understanding Comics

🔗 Books 🔗 Comics 🔗 Comics/DC Comics

Understanding Comics: The Invisible Art is a 1993 non-fiction work of comics by American cartoonist Scott McCloud. It explores formal aspects of comics, the historical development of the medium, its fundamental vocabulary, and various ways in which these elements have been used. It expounds theoretical ideas about comics as an art form and medium of communication, and is itself written in comic book form.

Understanding Comics received praise from notable comic and graphic novel authors such as Art Spiegelman, Will Eisner, Alan Moore, Neil Gaiman, and Garry Trudeau (who reviewed the book for the New York Times). Although the book has prompted debate over many of McCloud’s conclusions, its discussions of "iconic" art and the concept of "closure" between panels have become common reference points in discussions of the medium.

The title of Understanding Comics is an homage to Marshall McLuhan's seminal 1964 work Understanding Media.

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🔗 Type I and type II errors

🔗 Mathematics 🔗 Statistics

In statistical hypothesis testing, a type I error is the rejection of a true null hypothesis (also known as a "false positive" finding or conclusion), while a type II error is the non-rejection of a false null hypothesis (also known as a "false negative" finding or conclusion). Much of statistical theory revolves around the minimization of one or both of these errors, though the complete elimination of either is a statistical impossibility for non-deterministic algorithms. By selecting a low threshold (cut-off) value and modifying the alpha (p) level, the quality of the hypothesis test can be increased. The knowledge of Type I errors and Type II errors is widely used in medical science, biometrics and computer science.

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🔗 80k dollars almost certainly cures hepatitis C

🔗 Medicine 🔗 Pharmacology

Sofosbuvir, sold under the brand name Sovaldi among others, is a medication used to treat hepatitis C. It is only recommended with some combination of ribavirin, peginterferon-alfa, simeprevir, ledipasvir, daclatasvir, or velpatasvir. Cure rates are 30 to 97% depending on the type of hepatitis C virus involved. Safety during pregnancy is unclear; some of the medications used in combination may result in harm to the baby. It is taken by mouth.

Common side effects include feeling tired, headache, nausea, and trouble sleeping. Side effects are generally more common in interferon-containing regimens. Sofosbuvir may reactivate hepatitis B in those who have been previously infected. In combination with ledipasvir, daclatasvir or simeprevir it is not recommended with amiodarone due to the risk of an abnormally slow heartbeat. Sofosbuvir is in the nucleotide analog family of medication and works by blocking the hepatitis C NS5B protein.

Sofosbuvir was discovered in 2007, and approved for medical use in the United States in 2013. It is on the World Health Organization's List of Essential Medicines, the safest and most effective medicines needed in a health system. As of 2016, a 12-week course of treatment costs about US$84,000 in the United States, US$53,000 in the United Kingdom, US$45,000 in Canada, and about US$500 in India. Over 60,000 people were treated with sofosbuvir in its first 30 weeks being sold in the United States.

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🔗 Dujiangyan irrigation system

🔗 China/Chinese history 🔗 China 🔗 Civil engineering 🔗 Archaeology 🔗 Museums 🔗 World Heritage Sites


The Dujiangyan (Chinese: 都江堰; pinyin: Dūjiāngyàn) is an ancient irrigation system in Dujiangyan City, Sichuan, China. Originally constructed around 256 BC by the State of Qin as an irrigation and flood control project, it is still in use today. The system's infrastructure develops on the Min River (Minjiang), the longest tributary of the Yangtze. The area is in the west part of the Chengdu Plain, between the Sichuan basin and the Tibetan plateau. Originally, the Min would rush down from the Min Mountains and slow down abruptly after reaching the Chengdu Plain, filling the watercourse with silt, thus making the nearby areas extremely prone to floods. Li Bing, then governor of Shu for the state of Qin, and his son headed the construction of the Dujiangyan, which harnessed the river using a new method of channeling and dividing the water rather than simply damming it. The water management scheme is still in use today to irrigate over 5,300 square kilometres (2,000 sq mi) of land in the region. The Dujiangyan, the Zhengguo Canal in Shaanxi and the Lingqu Canal in Guangxi are collectively known as the "three great hydraulic engineering projects of the Qin."

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🔗 R/K selection theory

🔗 Evolutionary biology 🔗 Ecology

In ecology, r/K selection theory relates to the selection of combinations of traits in an organism that trade off between quantity and quality of offspring. The focus on either an increased quantity of offspring at the expense of individual parental investment of r-strategists, or on a reduced quantity of offspring with a corresponding increased parental investment of K-strategists, varies widely, seemingly to promote success in particular environments.

The terminology of r/K-selection was coined by the ecologists Robert MacArthur and E. O. Wilson in 1967 based on their work on island biogeography; although the concept of the evolution of life history strategies has a longer history (see e.g. plant strategies).

The theory was popular in the 1970s and 1980s, when it was used as a heuristic device, but lost importance in the early 1990s, when it was criticized by several empirical studies. A life-history paradigm has replaced the r/K selection paradigm but continues to incorporate many of its important themes.

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🔗 Ink trap

🔗 Typography

An ink trap is a feature of certain typefaces designed for printing in small sizes. At an ink trap, the corners or details are removed from the letterforms. When the type is printed, ink naturally spreads into the removed area. Without ink traps, the excess ink would soak outwards and ruin the crisp edge.

Ink traps are only needed for small point sizes and are usually only found on typefaces designed for printing on newsprint. Fonts of this kind are applicable for classifieds or telephone books. Typefaces with ink traps may be offered in versions without them for display on screen or at larger sizes.

Typefaces featuring ink traps include Retina, Bell Centennial, and Tang.

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