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Topic Review
V-twin Engine
A V-twin engine, also called a V2 engine, is a two-cylinder piston engine where the cylinders share a common crankshaft and are arranged in a V configuration. Although widely associated with motorcycles (installed either transversely or longitudinally), V-twin engines have also been used for industrial engines and in several small cars. The V-twin design dates back to the late 1880s.
  • 13.6K
  • 21 Oct 2022
Topic Review
Children's Television Series
Children's television series are television programs designed for children, normally scheduled for broadcast during the morning and afternoon when children are awake. They can sometimes run during the early evening, allowing younger children to watch them after school. The purpose of these shows is mainly to entertain or educate.
  • 13.6K
  • 28 Nov 2022
Topic Review
Socialism in One Country
Socialism in One Country was a theory put forth by Joseph Stalin and Nikolai Bukharin in 1924 which was eventually adopted by the Soviet Union as state policy. The theory held that given the defeat of all the communist revolutions in Europe in 1917–1923 except Russia, the Soviet Union should begin to strengthen itself internally. That turn toward national communism was a shift from the previously held position by classical Marxism that socialism must be established globally (world communism). However, proponents of the theory argue that it contradicts neither world revolution nor world communism. The theory was in opposition to Leon Trotsky's theory of permanent revolution.
  • 13.6K
  • 17 Oct 2022
Topic Review
Astana
Astana, previously known as Akmolinsk, Tselinograd, Akmola and most recently Nur-Sultan, is the capital city of Kazakhstan. The city lies on the banks of the Ishim River in the north-central part of Kazakhstan, within the Akmola Region, though administered as a city with special status separately from the rest of the region. A 2020 official estimate reported a population of 1,136,008 within the city limits, making it the second-largest city in the country, after Almaty, which had been the capital until 1997. The city became the capital of Kazakhstan in 1997; since then it has grown and developed economically into one of the most modern cities in Central Asia. In 2021, the government selected Astana as one of the 10 priority destinations for tourist development. Modern Astana is a planned city, following the process of other planned capitals. After it became the capital of Kazakhstan, the city dramatically changed its shape. The city's master-plan was designed by Japanese architect Kisho Kurokawa. As the seat of the government of Kazakhstan, Astana is the site of the Parliament House, the Supreme Court, the Ak Orda Presidential Palace and numerous government departments and agencies. It is home to a range of futuristic buildings, including many skyscrapers.
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  • 03 Mar 2023
Topic Review
Tesla Roadster (2008)
The Tesla Roadster is a battery electric vehicle (BEV) sports car, based on the Lotus Elise chassis, that was produced by the electric car firm Tesla Motors (now Tesla, Inc.) in California from 2008 to 2012. The Roadster was the first highway legal serial production all-electric car to use lithium-ion battery cells and the first production all-electric car to travel more than 320 kilometres (200 mi) per charge. It is also the first production car to be launched into orbit, carried by a Falcon Heavy rocket in a test flight on February 6, 2018. Tesla sold about 2,450 Roadsters in over 30 countries, and most of the last Roadsters were sold in Europe and Asia during the fourth quarter of 2012. Tesla produced right-hand-drive Roadsters from early 2010. The Roadster qualified for government incentives in several nations. According to the U.S. EPA, the Roadster can travel 393 kilometres (244 mi) on a single charge of its lithium-ion battery pack, and can accelerate from 0 to 97 km/h (0 to 60 mph) in 3.7 or 3.9 seconds depending on the model. It has a top speed of 201 km/h (125 mph). The Roadster's efficiency, (As of September 2008), was reported as 120 MPGe (2.0 L/100 km). It uses 135 Wh/km (21.7 kW·h/100 mi, 13.5 kW·h/100 km or 490 kJ/km) battery-to-wheel, and has an efficiency of 88% on average.
  • 13.6K
  • 11 Nov 2022
Topic Review
Importance, Properties and Benefits of Biochar
Biochar can be defined as the carbonaceous product that is obtained when biomass is subjected to heat treatment in an oxygen-limited environment (pyrolysis) and the charred product when applied to soil as an amendment. It is an important and popular carbon sequestration method to mitigate climate change.
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  • 15 Jun 2022
Topic Review
Allegory of the Cave
The Allegory of the Cave, or Plato's Cave, was presented by the Ancient Greece philosopher Plato in his work Republic (514a–520a) to compare "the effect of education (παιδεία) and the lack of it on our nature". It is written as a dialogue between Plato's brother Glaucon and his mentor Socrates, narrated by the latter. The allegory is presented after the analogy of the sun (508b–509c) and the analogy of the divided line (509d–511e). All three are characterized in relation to dialectic at the end of Books VII and VIII (531d–534e). Plato has Socrates describe a group of people who have lived chained to the wall of a cave all of their lives, facing a blank wall. The people watch shadows projected on the wall from objects passing in front of a fire behind them, and give names to these shadows. The shadows are the prisoners' reality. Socrates explains how the philosopher is like a prisoner who is freed from the cave and comes to understand that the shadows on the wall are not reality at all, for he can perceive the true form of reality rather than the manufactured reality that is the shadows seen by the prisoners. The inmates of this place do not even desire to leave their prison, for they know no better life. The prisoners manage to break their bonds one day, and discover that their reality was not what they thought it was. They discovered the sun, which Plato uses as an analogy for the fire that man cannot see behind. Like the fire that cast light on the walls of the cave, the human condition is forever bound to the impressions that are received through the senses. Even if these interpretations (or, in Kantian terminology, intuitions) are an absurd misrepresentation of reality, we cannot somehow break free from the bonds of our human condition—we cannot free ourselves from phenomenal state just as the prisoners could not free themselves from their chains. If, however, we were to miraculously escape our bondage, we would find a world that we could not understand—the sun is incomprehensible for someone who has never seen it. In other words, we would encounter another "realm", a place incomprehensible because, theoretically, it is the source of a higher reality than the one we have always known; it is the realm of pure Form, pure fact. Socrates remarks that this allegory can be paired with previous writings, namely the analogy of the sun and the analogy of the divided line.
  • 13.5K
  • 15 Nov 2022
Topic Review
Gadsden Flag
The Gadsden flag is a historical American flag with a yellow field depicting a timber rattlesnake coiled and ready to strike. Beneath the rattlesnake are the words: "Dont Tread on Me". Some modern versions of the flag include an apostrophe. The flag is named after politician Christopher Gadsden (1724–1805), who designed it in 1775 during the American Revolution. It was used by the Continental Marines as an early motto flag, along with the Moultrie flag. It is often used in the United States as a symbol for gun rights and limited government. There are Americans today that still display the Gadsden flag in support of freedom, independence, and for the United States military.
  • 13.5K
  • 22 Nov 2022
Topic Review
Armor-Piercing Shell
An armor-piercing shell, armour-piercing shell in Commonwealth English, AP for short, is a type of ammunition designed to penetrate armor. From the 1860s to 1950s, a major application of armor-piercing projectiles was to defeat the thick armor carried on many warships and cause damage to the lightly-armored interior. From the 1920s onwards, armor-piercing weapons were required for anti-tank missions. AP rounds smaller than 20 mm are typically known as "armor-piercing ammunition", and are intended for lightly-armored targets such as body armor, bulletproof glass and light armored vehicles. The AP shell is now seldom used in naval warfare, as modern warships have little or no armor protection. In the anti-tank role, as tank armor improved during World War II newer designs began to use a smaller but dense penetrating body within a larger shell. These lightweight shells were fired at very high muzzle velocity and retained that speed and the associated penetrating power over longer distances. An armor-piercing shell must withstand the shock of punching through armor plating. Shells designed for this purpose have a greatly strengthened body with a specially hardened and shaped nose. One common addition to later shells is the use of a softer ring or cap of metal on the nose known as a penetrating cap. This lowers the initial shock of impact to prevent the rigid shell from shattering, as well as aiding the contact between the target armor and the nose of the penetrator to prevent the shell from bouncing off in glancing shots. Ideally, these caps have a blunt profile, which led to the use of a further thin aerodynamic cap to improve long-range ballistics. AP shells may contain a small explosive charge known as a "bursting charge". Some smaller-caliber AP shells have an inert filling or an incendiary charge in place of the bursting charge. Designs using newer technologies no longer look like the classic artillery shell and have displaced it. Instead the penetrator is a long rod of dense material like tungsten or depleted uranium (DU) that further improves the terminal ballistics. Whether these modern designs are considered to be AP rounds depends on the definition. Accordingly reference sources vary in whether they include or exclude them.
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  • 02 Nov 2022
Topic Review
Indigenous Aryans
Indigenous Aryans, also known as the Out of India theory (OIT), is the idea that the Aryans are indigenous to the Indian subcontinent, and that the Indo-European languages radiated out from a homeland in India into their present locations. Reflecting traditional Indian views based on the Puranic chronology, the indigenist view proposes an older date than is generally accepted for the Vedic period, and argues that the Indus Valley Civilization was a Vedic civilization. In this view, "the Indian civilization must be viewed as an unbroken tradition that goes back to the earliest period of the Sindhu-Sarasvati (or Indus) tradition (7000 or 8000 BCE)." It is presented as an alternative to the established migration model, which proposes the Pontic steppe as the area of origin of the Indo-European languages. The proposal is based on traditional and religious views on Indian history and identity, and plays a signifcant role in Hindutva politics. Support for this idea mostly exists among Indian scholars of Hindu religion and the history and archaeology of India, and has no support in mainstream scholarship.
  • 13.5K
  • 13 Oct 2022
Topic Review
Gravity Well
A gravity well or gravitational well is a conceptual model of the gravitational field surrounding a body in space – the more massive the body, the deeper and more extensive the gravity well associated with it. The Sun is very massive, relative to other bodies in the Solar System, so the corresponding gravity well that surrounds it appears "deep" and far-reaching. The gravity wells of asteroids and small moons, conversely, are often depicted as very shallow. Anything at the center of mass of a planet or moon is considered to be at the bottom of that celestial body's gravity well, and so escaping the effects of gravity from such a planet or moon (to enter outer space) can be likened to "climbing out of the gravity well". The deeper a gravity well is, the more energy any space-bound "climber" must use to escape it. In astrophysics, a gravity well is specifically the gravitational potential field around a massive body. Other types of potential wells include electrical and magnetic potential wells. Physical models of gravity wells are sometimes used to illustrate orbital mechanics. Gravity wells are frequently confused with embedding diagrams used in general relativity theory, but the two concepts are distinctly separate and not directly related.
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  • 12 Oct 2022
Biography
Yuval Noah Harari
Yuval Noah Harari (Hebrew: יובל נח הררי‎, [juˈval ˈnoaχ (h)aˈʁaʁi]; born 24 February 1976) is an Israeli historian and a professor in the Department of History at the Hebrew University of Jerusalem.[1] He is the author of the popular science bestsellers Sapiens: A Brief History of Humankind (2014), Homo Deus: A Brief History of Tomorrow (2016), and 21 Lessons for the 21st Centu
  • 13.5K
  • 10 Nov 2022
Topic Review
Mail-Order Bride
A mail-order bride is a woman who lists herself in catalogs and is selected by a man for marriage. In the twentieth century, the trend was primarily towards women living in developing countries seeking men in more developed nations. In the twenty-first century, the trend is now based primarily on internet-based meeting places which do not per se qualify as mail-order bride services. The majority of the women listed in the twentieth-century and twenty-first-century services are from Southeast Asia, countries of the former Eastern Bloc and (to a lesser extent) from Latin America. Since the collapse of the Soviet Union, large numbers of eastern European women have advertised themselves in such a way, primarily from Russia , Belarus , Ukraine , and Moldova. Men who list themselves in such publications are referred to as "mail-order husbands", although this is much less common. The term "mail-order bride" is both criticized by owners (and customers) of international marriage agencies and used by them as an easily recognizable term.
  • 13.5K
  • 25 Nov 2022
Topic Review
List of Facebook Features
Facebook is a social-network service website launched on February 4, 2004 by Mark Zuckerberg. The following is a list of software and technology features that can be found on the Facebook website and mobile app and are available to users of the social media site.
  • 13.4K
  • 29 Nov 2022
Topic Review
Tracking Technology in Augmented Reality
Augmented reality (AR) is one of the leading expanding immersive experiences of the 21st century. AR has brought a revolution in different realms including health and medicine, teaching and learning, tourism, designing, manufacturing, and other similar industries whose acceptance accelerated the growth of AR in an unprecedented manner. The tracking technologies are the building blocks of AR and establish a point of reference for movement and for creating an environment where the virtual and real objects are presented together. To achieve a real experience with augmented objects, several tracking technologies are presented.
  • 13.4K
  • 03 Jan 2023
Topic Review
Bell Test Experiments
A Bell test experiment or Bell's inequality experiment, also simply a Bell test, is a real-world physics experiment designed to test the theory of quantum mechanics in relation to Albert Einstein's concept of local realism. The experiments test whether or not the real world satisfies local realism, which requires the presence of some additional local variables (called "hidden" because they are not a feature of quantum theory) to explain the behavior of particles like photons and electrons. To date, all Bell tests have found that the hypothesis of local hidden variables is inconsistent with the way that physical systems behave. According to Bell's theorem, if nature actually operates in accord with any theory of local hidden variables, then the results of a Bell test will be constrained in a particular, quantifiable way. If a Bell test is performed in a laboratory and the results are not thus constrained, then they are inconsistent with the hypothesis that local hidden variables exist. Such results would support the position that there is no way to explain the phenomena of quantum mechanics in terms of a more fundamental description of nature that is more in line with the rules of classical physics. Many types of Bell test have been performed in physics laboratories, often with the goal of ameliorating problems of experimental design or set-up that could in principle affect the validity of the findings of earlier Bell tests. This is known as "closing loopholes in Bell test experiments". In a novel experiment conducted in 2016, over 100,000 volunteers participated in an online video game that used human choices to produce the data for researchers conducting multiple independent tests across the globe.
  • 13.4K
  • 29 Nov 2022
Topic Review
Pingu
Pingu is a Swiss-British stop-motion clay animated children's comedy television series created by Otmar Gutmann and produced from 1990 to 2000 for Swiss television, and from 2003 to 2006 for British television by The Pygos Group (formerly Trickfilmstudio and Pingu Filmstudio). It centres on a family of anthropomorphic penguins who live at the South Pole; the main character is the family's son and title character, Pingu. The series originally ran for four series (each series made up of multiple seasons) from 7 March 1990 to 9 April 2000 on SF DRS and was then renewed for two more series from 1 August 2003 to 3 March 2006 on BBC Two. Pingu won a BAFTA award. Pingu was a worldwide hit, due to its lack of real spoken language: nearly all dialogue is in an invented grammelot "penguin language" referred to as 'Penguinese', consisting of babbling, muttering, and his characteristic sporadic loud honking noise, which can be popularly recognized as "Noot noot!" or other variants, stated to be "Noo, Noo!" by the defunct Pingu website's trivia page, accompanied by turning his beak into a megaphone-like shape. Within the first 4 series, all the characters were performed by Italian voice actor Carlo Bonomi, using a language of noises that he had already developed and used for the earlier Osvaldo Cavandoli's La Linea. In series 5 and 6, the Pingu cast was jointly voiced by David Sant and Marcello Magni. A Japanese reboot of the series, titled Pingu in the City, began airing on NHK-E on 7 October 2017.
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  • 12 Oct 2022
Topic Review
Data Envelopment Analysis (DEA)
Data Envelopment Analysis (DEA) is a non-parametric methodology for measuring the efficiency of Decision Making Units (DMUs) using multiple inputs to outputs configurations. This is the most commonly used tool for frontier estimations in assessments of productivity and efficiency applied to all fields of economic activities.
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  • 28 Jan 2022
Topic Review
The Tryptophan-Kynurenine Metabolic Pathway
Tryptophan (TRP) is one of the essential amino acids, which participates in protein synthesis. The tryptophan’s main metabolic route is the kynurenine pathway (KP) through which approximately 90-95% of TRP degrades into nicotinamide adenine dinucleotide (NAD+) and other bioactive metabolites. The appropriate amount of NAD+ is essential to maintain the operation and the viability of cells. The other molecules are neurotoxic, neuroprotective, oxidant, antioxidant, and/or immune modifiers. They play an important role in the function of the brain and the peripheral tissues. The change in the levels of the bioactive molecules is considered to contribute to the development of a wide range of illnesses from cancer to immunologic, neurodegenerative, and psychiatric diseases.
  • 13.4K
  • 10 Aug 2021
Topic Review
Puruṣārtha
Puruṣārtha (Sanskrit: पुरुषार्थ) literally means an "object of human pursuit". It is a key concept in Hinduism, and refers to the four proper goals or aims of a human life. The four puruṣārthas are Dharma (righteousness, moral values), Artha (prosperity, economic values), Kama (pleasure, love, psychological values) and Moksha (liberation, spiritual values). All four Purusarthas are important, but in cases of conflict, Dharma is considered more important than Artha or Kama in Hindu philosophy. Moksha is considered the ultimate ideal of human life. At the same time, this is not a consensus among all Hindus, and many have different interpretations of the hierarchy, and even as to whether one should exist. Historical Indian scholars recognized and debated the inherent tension between active pursuit of wealth (Artha purusartha) and pleasure (Kama), and renunciation of all wealth and pleasure for the sake of spiritual liberation (Moksha). They proposed "action with renunciation" or "craving-free, dharma-driven action", also called Nishkam Karma as a possible solution to the tension.
  • 13.4K
  • 14 Oct 2022
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