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Topic Review
Buyeo Languages
The Buyeo languages, or Fuyu languages (Korean: 부여; Chinese: 扶餘, Fúyú), is a theoretical language family that consists of the Koreanic languages, the Japonic languages and of the ancient languages of the Korean Peninsula and Manchuria. According to ancient Chinese records, the languages of Buyeo, Goguryeo, Dongye, Okjeo, Baekje and Gojoseon were similar to one another but very different from Tungusic languages. The Ye-Maek language may have been ancestral.
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  • 08 Oct 2022
Topic Review
Gearbox Technologies for Tidal Energy Harvesting
Gearboxes are widely used in automobile, aerospace, energy, and process industries and are considered indispensable. Tidal flows always have very low speeds that rarely exceed 5 m/s. Lower tidal speeds result in lower turbine rotation speeds. Therefore, if conventional generators are used to produce electricity, gearboxes are necessary to achieve higher rotor speeds. 
  • 3.0K
  • 26 Dec 2022
Topic Review
Law of the Land
The phrase law of the land is a legal term, equivalent to the Latin lex terrae, or legem terrae in the accusative case. It refers to all of the laws in force within a country or region, including statute law and case-made law.
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  • 04 Nov 2022
Biography
James Heppelmann
James E. Heppelmann (born September 4, 1964) [1] is an American engineer and businessman. He is the chief executive officer (CEO) of PTC (software company) (formerly Parametric Technology) a multinational software company he joined in January of 1998 as Senior Vice President Windchill, Parametric Technology Corp. Heppelmann grew up in rural Minnesota on a small dairy farm with his seven sibli
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  • 29 Dec 2022
Topic Review
Commuter Behaviour
Lack of travel demand measures to curb private vehicles in the city, leading to the problem of traffic congestion in the emerging megacities. Analysis of the problem of traffic congestion to commuter travel mode preferences in the city opens up the door for theoretical exploration of the process of traffic congestion. The study reports the analysis of the framed field experiment to investigate the behavioural responses of commuters. By involving 204 commuters, the research is aimed to investigate the behavioural response of commuters if demand-based non-technical measures are implemented as treatments in the experiment. The two central questions related to this objective are: how do commuter travel mode preferences contribute to urban traffic congestion? And, how can this be empirically analysed in terms of the effect of demand-based non-technical measures?
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  • 27 Oct 2020
Topic Review
Nitrogen in Wetlands
Wetlands are viable sinks for nitrate and have also been identified as a source of nitrous oxide, a product of two microbially regulated processes: nitrification and denitrification. Anthropogenic expansion of nitrogen is a leading cause of the eutrophication of water bodies and may also contribute to the deterioration of the ozone layer in the stratosphere. Wetlands ameliorate the quality of water percolating through them, by retaining nutrients and sequestering carbon, and simultaneously enhancing the flora and fauna diversity of these landscapes. Among the many services these wetlands provide, they also alleviate nitrate pollution by attenuating reactive nitrogen from agricultural drainage and ensure the effective reclamation of the wastewater. 
  • 3.0K
  • 24 May 2021
Topic Review
Near-Infrared Spectrum of Olive Oils
Olive oil is regarded as one of the healthiest food oils due to its high content in triglycerides with unsaturated acids, mainly oleic acid, and its phenolic composition. The analysis of the physico-chemical parameters of quality of olive oil is still carried out in laboratories using chemicals and generating waste, which is relatively costly and time-consuming. Among the various alternatives for the online or on-site measurement of these parameters, the available literature highlights the use of near-infrared spectroscopy (NIRS). 
  • 3.0K
  • 18 Apr 2022
Topic Review
Microalgae
Recently, microalgal biotechnology has received increasing interests in producing valuable, sustainable and environmentally friendly bioproducts. The development of economically viable production processes entails resolving certain limitations of microalgal biotechnology, and fast evolving genetic engineering technologies have emerged as new tools to overcome these limitations. 
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  • 05 May 2022
Topic Review
Varangian Guard
The Varangian Guard (Greek: Τάγμα τῶν Βαράγγων, Tágma tōn Varángōn) was an elite unit of the Byzantine Army, from the 10th to the 14th centuries, whose members served as personal bodyguards to the Byzantine Emperors. They are known for being primarily composed of Germanic peoples, specifically Norsemen from modern day Sweden (the Guard was formed approximately 200 years into the Viking Age) and Anglo-Saxons (after the Norman Conquest of England created an Anglo-Saxon diaspora, part of which found employment in Constantinople). The Rus' provided the earliest members of the Varangian Guard. They were in Byzantine service from as early as 874. The Guard was first formally constituted under Emperor Basil II in 988, following the Christianization of Kievan Rus' by Vladimir I of Kiev. Vladimir, who had recently usurped power in Kiev with an army of Varangian warriors, sent 6,000 men to Basil as part of a military assistance agreement. Basil's distrust of the native Byzantine guardsmen, whose loyalties often shifted, with fatal consequences, as well as the proven loyalty of the Varangians, many of whom had previously served in Byzantium, led the Emperor to employ them as his personal guardsmen. Immigrants from Sweden, Denmark , Norway and Iceland kept a predominantly Norse cast to the organization until the late 11th century. According to the late Swedish historian Alf Henrikson in his book Svensk Historia (History of Sweden), the Scandinavian Varangian guardsmen were recognized by long hair, a red ruby set in the left ear and ornamented dragons sewn on their chainmail shirts. In these years, Scandinavian men left to enlist in the Byzantine Varangian Guard in such numbers that a medieval Swedish law, Västergötlagen, from Västergötland declared no one could inherit while staying in "Greece"—the then Scandinavian term for the Byzantine Empire—to stop the emigration, especially as two other European courts simultaneously also recruited Scandinavians: Kievan Rus' c. 980–1060 and London 1018–1066 (the Þingalið). Composed primarily of Norsemen and Rus for the first 100 years, the Guard began to see increased numbers of Anglo-Saxons after the Norman conquest of England. By the time of the Emperor Alexios Komnenos in the late 11th century, the Varangian Guard was largely recruited from Anglo-Saxons and "others who had suffered at the hands of the Vikings and their cousins the Normans". The Anglo-Saxons and other Germanic peoples shared with the Vikings a tradition of faithful (to death if necessary) oath-bound service, and the Norman invasion of England resulted in many fighting men who had lost their lands and former masters and were looking for positions elsewhere. The Varangian Guard not only provided security for the Byzantine emperors, but also participated in many wars, often playing a decisive role, since they were usually deployed at critical moments of a battle. By the late 13th century, Varangians were mostly ethnically assimilated by the Byzantine Greeks, though the Guard remained in existence until at least mid-14th century. In 1400, there were still some people identifying themselves as "Varangians" in Constantinople.
  • 3.0K
  • 04 Nov 2022
Biography
Simcha Jacobovici
Simcha Jacobovici (/ˈsɪmxə jəˈkoʊboʊvɪtʃ/, born April 4, 1953, Petah Tikva, Israel) is an Israeli-Canadian film director, producer, freelance journalist, and writer. His parents were from Iași, Romania.[1] Simcha Jacobovici earned a B.A. in Philosophy and Political Science (with honors) from McGill University and an M.A. in International Relations from the University of Toronto. He
  • 3.0K
  • 15 Nov 2022
Topic Review
Sockpuppet (Internet)
A sockpuppet is an online identity used for purposes of deception. The term, a reference to the manipulation of a simple hand puppet made from a sock, originally referred to a false identity assumed by a member of an Internet community who spoke to, or about, themselves while pretending to be another person. The use of the term has expanded to now include other misleading uses of online identities, such as those created to praise, defend or support a person or organization, to manipulate public opinion, or to circumvent restrictions, suspension or an outright ban from a website. A significant difference between the use of a pseudonym and the creation of a sockpuppet is that the sockpuppet poses as an independent third-party unaffiliated with the main account operator. Sockpuppets are unwelcome in many online communities and forums.
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  • 15 Nov 2022
Topic Review
Hadrosauridae
Hadrosaurids (from grc ἁδρός (hadrós) 'stout, thick', and σαύρα (saúra) 'lizard'), or duck-billed dinosaurs, are members of the ornithischian family Hadrosauridae. This group is known as the duck-billed dinosaurs for the flat duck-bill appearance of the bones in their snouts. The ornithopod family, which includes genera such as Edmontosaurus and Parasaurolophus, was a common group of herbivores during the Late Cretaceous Period. Hadrosaurids are descendants of the Upper Jurassic/Lower Cretaceous iguanodontian dinosaurs and had a similar body layout. Hadrosaurs were among the most dominant herbivores during the Late Cretaceous in Asia and North America, and during the close of the Cretaceous several lineages dispersed into Europe, Africa, South America and Antarctica. Like other ornithischians, hadrosaurids had a predentary bone and a pubic bone which was positioned backwards in the pelvis. Unlike more primitive iguanodonts, the teeth of hadrosaurids are stacked into complex structures known as dental batteries, which acted as effective grinding surfaces. Hadrosauridae is divided into two principal subfamilies: the lambeosaurines (Lambeosaurinae), which had hollow cranial crests or tubes; and the saurolophines (Saurolophinae), identified as hadrosaurines (Hadrosaurinae) in most pre-2010 works, which lacked hollow cranial crests (solid crests were present in some forms). Saurolophines tended to be bulkier than lambeosaurines. Lambeosaurines included the aralosaurins, tsintaosaurins, lambeosaurins and parasaurolophins, while saurolophines included the brachylophosaurins, kritosaurins, saurolophins and edmontosaurins. Hadrosaurids were facultative bipeds, with the young of some species walking mostly on two legs and the adults walking mostly on four.
  • 3.0K
  • 02 Dec 2022
Topic Review
Breakdown Voltages in Different Types of Gases
The idea of using a vacuum as an insulating medium is to take advantage of the fact that when the gas pressure is reduced to a value at which the average free paths of molecules and electrons are greater than the contact gap in the insulating system, the development of electron avalanches that initiate discharges in gases is impossible.
  • 3.0K
  • 07 Sep 2022
Topic Review
Astaxanthin on Human Skin Ageing
Skin ageing is becoming a global challenge due to longer human longevity and intensive ultra-violet rays contributed to the ozone layer destruction, attracting greater scientific interests in developing nutricoesmetic products, especially from natural functional ingredients with lower side-effects. Astaxanthin, a carotenoid with high antioxidant and anti-inflammatory effects, which could be extracted from the byproduct of processed crustaceans, prevented skin photoaging and age-related skin diseases in the animal models. But these byproducts are generally discarded as marine waste, losing potentially valuable ingredients, and causing serious environmental problems by accumulating high amounts of organic materials. ASX may have cosmetical potential to prevent or reverse human skin ageing, which has been evaluated in several previous papers. Here, we conducted a systemic review and meta-analysis to help clarify its human skincare effects, which promote marine waste recycling, environmental protection, and sustainable development.   
  • 3.0K
  • 09 Sep 2021
Topic Review
Succession Pathways in Mixed Forests of Pacific Northwest
Forest succession is an ecological phenomenon that can span centuries. Nowadays it is recognized that stochastic events and disturbances play a pivotal role in forest succession. In spite of that, forest maps and management plans around the world are developed and focused on a unique “climax” community, likely due to the difficulty of quantifying alternative succession pathways. Our work demonstrated that a three-pathway stochastic succession model can mimic the observed landscape distribution among different stand types before commercial logging started in the region. We conclude that, while knowing the difficulty of parameterizing this type of models, their use is needed to recognize that for a given site, there may be multiple “climax” communities and hence forest management should account for them.
  • 3.0K
  • 29 Dec 2021
Topic Review
School Recess: Safety Situations and Assumable Risk
Recess at school takes place during the school day to provide the children with a change from academic activities. In the field of education, rest times within the academic activities at school are necessary for the healthy development of children and as tools to promote learning, bringing health, social, cognitive, and developmental benefits.
  • 3.0K
  • 21 Apr 2022
Topic Review
Keychain
A keychain, or keyring, is a small chain, usually made from metal or plastic, that connects a small item to a keyring. The length of a keychain allows an item to be used more easily than if connected directly to a keyring. Some keychains allow one or both ends the ability to rotate, keeping the keychain from becoming twisted, while the item is being used. A keychain can also be a connecting link between a keyring and the belt of an individual. It is usually employed by personnel whose job demands frequent use of keys, such as a security guard, prison officer, janitor, or retail store manager. The chain is often retractable, and therefore may be a nylon rope, instead of an actual metal chain. The chain ensures that the keys remain attached to the individual using them, makes accidental loss less likely, and saves on wear and tear on the pockets of the user.
  • 3.0K
  • 20 Oct 2022
Topic Review
Elasticity
In physics and materials science, elasticity is the ability of a body to resist a distorting influence and to return to its original size and shape when that influence or force is removed. Solid objects will deform when adequate loads are applied to them; if the material is elastic, the object will return to its initial shape and size after removal. This is in contrast to plasticity, in which the object fails to do so and instead remains in its deformed state. The physical reasons for elastic behavior can be quite different for different materials. In metals, the atomic lattice changes size and shape when forces are applied (energy is added to the system). When forces are removed, the lattice goes back to the original lower energy state. For rubbers and other polymers, elasticity is caused by the stretching of polymer chains when forces are applied. Hooke's law states that the force required to deform elastic objects should be directly proportional to the distance of deformation, regardless of how large that distance becomes. This is known as perfect elasticity, in which a given object will return to its original shape no matter how strongly it is deformed. This is an ideal concept only; most materials which possess elasticity in practice remain purely elastic only up to very small deformations, after which plastic (permanent) deformation occurs. In engineering, the elasticity of a material is quantified by the elastic modulus such as the Young's modulus, bulk modulus or shear modulus which measure the amount of stress needed to achieve a unit of strain; a higher modulus indicates that the material is harder to deform. The SI unit of this modulus is the pascal (Pa). The material's elastic limit or yield strength is the maximum stress that can arise before the onset of plastic deformation. Its SI unit is also the pascal (Pa).
  • 3.0K
  • 06 May 2023
Topic Review
Hindu Mythology
Template:Hindu mythology Hindu mythology are narratives found in Hindu texts such as the Vedic literature, epics like Mahabharata and Ramayana, the Puranas, the regional literatures Sangam literature and Periya Puranam. Hindu mythology is also found in widely translated popular texts such as the Panchatantra and Hitopadesha, as well as Southeast Asian texts. Hindu mythology does not often have a consistent, monolithic structure. The same myth typically appears in various versions, and can be represented differently across socio-religious traditions. These myths have also been noted to have been modified by various philosophical schools over time and particularly in the Hindu tradition. These myths are taken to have deeper, often symbolic, meaning, and have been given a complex range of interpretations.
  • 3.0K
  • 02 Dec 2022
Topic Review
Probabilistic Optimization Techniques in Smart Power System
Stochastic programming is used to solve optimization problems in which the majority of the parameters are probabilistic. Probabilistic optimization can make efficient use of information, both in terms of selecting evaluation points and the message they convey. It can handle many sorts of noise and adapts to various aspects of optimization issues. Unlike deterministic optimization, probabilistic optimization techniques discover the best solution for data with randomness.
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  • 17 Feb 2022
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