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Topic Review
Columbia Business School
Columbia Business School (CBS) is the business school of Columbia University in the City of New York in Manhattan, New York City . Established in 1916, Columbia Business School is one of the oldest business schools in the world. It is one of six Ivy League business schools, and is among the most selective of top business schools.
  • 6.0K
  • 11 Oct 2022
Topic Review
Crash Boats of World War 2
Crash boats, at the time known as "aircraft rescue boat" or "air-sea rescue boat" were wooden speedboats built to rescue the crew of downed United States and other Allies aircraft during World War II. US boats came from observation of British experience with High-speed launches during the Battle of Britain. By the end of World War II America had produced 300,000 planes, creating a need to have crash rescue boats stationed around the globe. These boats were fast boats used to rescue pilots, crew and passengers from downed aircraft in search and rescue, air-sea rescue missions. The boats would race out to a crash site and rescue wounded aircrew. Some speed boats built before the war were acquired and converted to be crash boats and many new boats were built. Standard crash boats were built in four lengths for World War II. The smallest standard size boat was 42 feet long. The larger boats were 63 or 85 or 104 feet long. They were built for the Army Air Forces, US Navy and some were transferred to Allies. The design was similar to patrol boats built for the war, but with less or no armament and first aid equipped. The boats were designed to be light and fast to be able to get to the downed aircrew as fast as possible. Most were used in the Pacific war across the vast South Pacific, in the Island hopping campaign. Some were station on the West Coast of the United States to support the vast training centers. Many were designated Air Rescue Boats or ARB or AVR or P or C or R Hull classification symbol. After the war most were abandoned or destroyed, a few served in the Korean war (with United States Air Force ), some sold to private and some donated to Sea Scouts.
  • 6.0K
  • 23 Nov 2022
Topic Review
Poisonous Plants of the Indian Himalaya
Indian Himalayan region (IHR) supports a wide diversity of plants and most of them are known for their medicinal value. Humankind has been using medicinal plants since the inception of civilization. Various types of bioactive compounds are found in plants, which are directly and indirectly beneficial for plants as well as humans. These bioactive compounds are highly useful and being used as a strong source of medicines, pharmaceuticals, agrochemicals, food additives, fragrances, and flavoring agents. Apart from this, several plant species contain some toxic compounds that affect the health of many forms of life as well as cause their death. These plants are known as poisonous plants, because of their toxicity to both humans and animals.
  • 6.0K
  • 27 Jul 2022
Topic Review
Thermodynamic Dissipation Theory of Life
The Thermodynamic Dissipation Theory of the Origin and Evolution of Life argues that the escence of the origin of life was the microscopic dissipative structuring under UVC light of organic pigments (now known as the fundamental molecules of life - those common to all three domains) and their proliferation over the entire Earth surface, driven by the thermodynamic imperative of dissipating this part of the Archean solar spectrum into heat. With time, dissipative structuring led to ever more complex biosynthetic pathways for creating pigments and their support structures (and processes) which could dissipate not only the UVC region but also other UV regions and the visible wavelengths, until today reaching the "red edge" (at approximately 700 nm). The heat of dissipation of photons absorbed on organic pigments in water then catalyzes a host of coupled secondary dissipative processes such as; the water cycle, ocean and wind currents, hurricanes, etc. pushing the limit for dissipation of the incident light even further towards the infrared. The thermodynamic dissipation theory thus assgins an explicit thermodynamic function to life; the dissipative structuring, proliferation, and evolution of molecular pigments and their complexes from common precursor carbon based molecules under the impressed short wavelength solar photon potential to perform the explicit thermodynamic function of dissipating this light into long wavelength infrared light (heat). In a general sense, the origin of life is no different than the origin of other dissipative structuring processes like hurricanes and the water cycle, except that these latter processes deal with structuring involving hydrogen bonding while life deals with structuring involving covalent bonding. The external photon potential supplied continuously by the environment (our Sun), and its dissipation into heat by the assembly of dissipative structures, are, therefore, both integral components necessary for understanding life. Difficult problems related to the origin of life, such as enzyme-less replication of RNA and DNA, homochirality of the fundamental molecules, and the origin of amino acid -codon assignments (information encoding in RNA and DNA), also find simple explanations within this same dissipative thermodynamic framework once the existence of a relation between primordial RNA and DNA replication and UV-C photon dissipation is established.
  • 6.0K
  • 04 Feb 2021
Topic Review
Smart Glass
The term “smart window” was coined by Granqvist in 1985. From the early 1980s, smart glazing has been a rapidly developing innovative technology that is aimed to help manage energy transfer through the building’s envelope, evading unnecessary “cooling and heating of indoor air”. The use of smart glass, which helps to regulate the amount of light (and heat) entering a building, is one of the possible ways to reduce energy consumption in buildings while maintaining an appropriate level of comfort for users. Smart glass greatly influences the building envelope performance in (i) thermal management, (ii) daylight harvesting and regulation, (iii) reduction of glare, (iv) maintenance of views, (v) power capture, and finally (vi) activating the envelope as an information display. Some technologies are currently available on the market, although—in light of the many shortcomings of the existing solutions—smart glass is the subject of ongoing “intensive research aimed at improving the technology and its widespread use”.
  • 6.0K
  • 23 Sep 2021
Topic Review
Post-Study System Usability Questionnaire
The Post-Study System Usability Questionnaire (PSSUQ) is an evaluation tool used to assess perceived usability, and it does not require a license for its usage. As PSSUQ is a common and widely used usability tool it has been translated into many languages, mainly European.
  • 6.0K
  • 20 Sep 2023
Topic Review Peer Reviewed
Louis XI of Valois (1461–1483)
Louis XI (1461–1483) was the sixth king of the Valois branch of the Capetian dynasty in France; he ruled from 1463 until his death in 1483. Louis was the son of Charles VII (1403–1461) and Marie of Anjou (1404–1463). While Dauphin, he married first Margaret of Scotland (1424–1445) and then Charlotte of Savoie (c.1441–1483), who bore him four surviving children: Anne de France, Jeanne de France, François de France, and the future Charles VIII. Louis’ key challenge as monarch was to pick up the pieces of a kingdom ravaged by the Hundred Years War between England and France (1337–1453). His legacy was to have repaired the kingdom’s depleted coffers through a combination of frugality and territorial expansion. His historiography paints him as a paranoid, manipulative, and obsessively pious ruler, a simplistic portrait that is undermined by a close examination of his artistic patronage. This entry will focus on the iconography he employed across a variety of media to promote the sacred legitimacy of his rule and to unify the peoples of France’s newly acquired territories. 
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  • 07 Jun 2022
Topic Review
Solar Reflectance Measurement
The relative amount of solar radiation reflected by a surface is specified as solar reflectance, or albedo. The latter term sometimes refers only to visible sunlight (Vis), while the former generally refers to the entire spectrum of solar radiation, including near-infrared (NIR) and ultraviolet (UV) radiation. However, the scientific and technical communities consider albedo and solar reflectance synonymous, with both referring to the entire solar spectrum. Solar reflectance is usually expressed as a value between zero, for a surface absorbing all incoming radiation, and one, for a perfect reflector—or as a percentage between 0 and 100%. For an opaque surface, solar reflectance is complementary to solar absorptance—that is, the ratio of absorbed to total incident solar energy. Several instruments are available for its measurement, in the laboratory on in situ, according to several standard test methods.
  • 6.0K
  • 23 Nov 2021
Topic Review
Virtual Power Plants (VPPs)
A virtual power plants (VPPs) is an alternative for the management of Distributed Energy Resources (DER) in the electricity system, which operates based on the concept of the “virtual cloud”. Its specific role is visibility and the technical and commercial integration of DERs in the power system. It is capable of grouping and managing the technical potential of different DERs (microgrids included), regardless of the voltage level at which they are interconnected with the network and without a geographical restriction between the elements. It is modeled as a single virtual element associated with the distribution network to guarantee a safe, efficient, cooperative and complementary operation between its elements, both in commercial and technical aspects. The VPP has the capacity to participate in the electricity market as a manager of controllable loads and as a provider of energy, power reserve and ancillary services.
  • 6.0K
  • 18 Feb 2022
Topic Review
Routing Protocol for Low Power and Lossy Network
The IETF Routing Over Low power and Lossy network (ROLL) working group defined IPv6 Routing Protocol for Low Power and Lossy Network (RPL) to facilitate efficient routing in IPv6 over Low-Power Wireless Personal Area Networks (6LoWPAN). Limited resources of 6LoWPAN nodes make it challenging to secure the environment, leaving it vulnerable to threats and security attacks. Machine Learning (ML) and Deep Learning (DL) approaches have shown promise as effective and efficient mechanisms for detecting anomalous behaviors in RPL-based 6LoWPAN.
  • 6.0K
  • 19 May 2022
Biography
Arthur Conan Doyle
Sir Arthur Ignatius Conan Doyle KStJ DL (22 May 1859 – 7 July 1930) was a British writer and physician. He created the character Sherlock Holmes in 1887 for A Study in Scarlet, the first of four novels and fifty-six short stories about Holmes and Dr. Watson. The Sherlock Holmes stories are considered milestones in the field of crime fiction. Doyle was a prolific writer; other than Holmes sto
  • 6.0K
  • 06 Dec 2022
Topic Review
Alternating Direction Implicit Method
In numerical linear algebra, the Alternating Direction Implicit (ADI) method is an iterative method used to solve Sylvester matrix equations. It is a popular method for solving the large matrix equations that arise in systems theory and control, and can be formulated to construct solutions in a memory-efficient, factored form. It is also used to numerically solve parabolic and elliptic partial differential equations, and is a classic method used for modeling heat conduction and solving the diffusion equation in two or more dimensions. It is an example of an operator splitting method.
  • 6.0K
  • 14 Oct 2022
Topic Review
Transactinide Element
In chemistry, transactinide elements (also, transactinides, or super-heavy elements) are the chemical elements with atomic numbers from 104 to 120. Their atomic numbers are immediately greater than those of the actinides, the heaviest of which is lawrencium (atomic number 103). Glenn T. Seaborg first proposed the actinide concept, which led to the acceptance of the actinide series. He also proposed the transactinide series ranging from element 104 to 121 and the superactinide series approximately spanning elements 122 to 153. The transactinide seaborgium was named in his honor. By definition, transactinide elements are also transuranic elements, i.e. have an atomic number greater than uranium (92). The transactinide elements all have electrons in the 6d subshell in their ground state. Except for rutherfordium and dubnium, even the longest-lasting isotopes of transactinide elements have extremely short half-lives, measured in seconds, or smaller units. The element naming controversy involved the first five or six transactinide elements. These elements thus used systematic names for many years after their discovery had been confirmed. (Usually the systematic names are replaced with permanent names proposed by the discoverers relatively shortly after a discovery has been confirmed.) Transactinides are radioactive and have only been obtained synthetically in laboratories. None of these elements has ever been collected in a macroscopic sample. Transactinide elements are all named after physicists and chemists or important locations involved in the synthesis of the elements. IUPAC defines an element to exist if its lifetime is longer than 10−14 seconds, which is the time it takes for the nucleus to form an electron cloud.
  • 6.0K
  • 01 Dec 2022
Topic Review
Gas Turbines with Water Injection and Full Evaporation
The concept behind humidifying gas turbines is that increasing the amount of water/steam injected into the turbine increases the amount of mass it moves. This results in a rise in the specific power output because the effort exerted by the compressor remains the same, and it takes far less effort to raise the pressure of a liquid than it does of a gas. The efficiency of the cycle may be improved by recovering the energy contained in the gas turbine’s exhaust and either preheating the injection water, making injection steam, or the recuperator’s preheating of the combustion oxidizer. The introduction of water prior to the combustor of a recuperated gas turbine lowers the compressed air’s temperature at the input of the recuperator. This results in an increase in the rate at which energy is recovered from the exhaust gas.
  • 6.0K
  • 27 Dec 2022
Topic Review
Ivermectin during the COVID-19 Pandemic
Ivermectin (IVM) is a broad-spectrum antiparasitic agent, developed and funded by Merck & Co. in 1974 to control and eradicate onchocerciasis caused by the parasitic worm Onchocerca volvulus in West Africa, which in the 1980s infected approximately 340,000 people. At the time, Africa did not have the resources necessary to seek treatments for this condition. The avermectins, of which IVM is a member, were discovered by Professor Satoshi Ōmura as fermentation products of the bacterium Streptomyces avermitilis at the Kitasato Institute in Tokyo. For this discovery, he received the 2015 Nobel Prize in Physiology and Medicine, which he shared with William Campbell. IVM is used to treat onchocerciasis, lymphatic filariasis, strongyloidiasis and scabies, and, very recently, has been used to combat lice. The drug’s low cost, high efficacy, safety, and marked tropism for helminths, as well as the fact that it has almost no impact on human biochemistry, have led to the inclusion of IVM in the twentieth list of essential medicines and sixth list of vital medicines in children, a recommendation made by the expert committee of the World Health Organization (WHO) in 2019. The safety profile is attributed to its selective affinity for ion channels.
  • 6.0K
  • 22 Sep 2022
Topic Review
Biocoagulant/bioflocculant application for drinking water
The utilization of metal-based conventional coagulants/flocculants to remove suspended solids from drinking water and wastewater is currently leading to new concerns. Alarming issues related to the prolonged effects on human health and further pollution to aquatic environments from the generated nonbiodegradable sludge are becoming trending topics. The utilization of biocoagulants/bioflocculants does not produce chemical residue in the effluent and creates nonharmful, biodegradable sludge.
  • 6.0K
  • 25 Dec 2020
Topic Review
Wood Formation in Plants
Unlike herbaceous plants, woody plants undergo volumetric growth (a.k.a. secondary growth) through wood formation, during which the secondary xylem (i.e., wood) differentiates from the vascular cambium. Wood is the most abundant biomass on Earth and, by absorbing atmospheric carbon dioxide, functions as one of the largest carbon sinks. As a sustainable and eco-friendly energy source, lignocellulosic biomass can help address environmental pollution and the global climate crisis.
  • 6.0K
  • 15 Jul 2022
Topic Review
Panzer II Variants
The Panzerkampfwagen II (Pz.Kpfw.II) light tank, produced in Germany in the late 1930s and early 1940s had a wide array of variants, both as development of the light tank and for specialised tasks.
  • 6.0K
  • 02 Nov 2022
Topic Review
Organ
In biology, an organ is a collection of tissues joined in a structural unit to serve a common function. In the hierarchy of life, an organ lies between tissue and an organ system. Tissues are formed from same type cells to act together in a function. Tissues of different types combine to form an organ which has a specific function. The intestinal wall for example is formed by epithelial tissue and smooth muscle tissue. Two or more organs working together in the execution of a specific body function form an organ system, also called a biological system or body system. An organ's tissues can be broadly categorized as parenchyma, the functional tissue, and stroma, the structural tissue with supportive, connective, or ancillary functions. For example, the gland's tissue that makes the hormones is the parenchyma, whereas the stroma includes the nerves that innervate the parenchyma, the blood vessels that oxygenate and nourish it and carry away its metabolic wastes, and the connective tissues that provide a suitable place for it to be situated and anchored. The main tissues that make up an organ tend to have common embryologic origins, such as arising from the same germ layer. Organs exist in most multicellular organisms. In single-celled organisms such as bacteria, the functional analogue of an organ is known as an organelle. In plants, there are three main organs. In the study of anatomy, viscera (singular viscus) refers to the internal organs of the abdominal, thoracic, and pelvic cavities. The abdominal organs may be classified as solid organs, or hollow organs. The solid organs are the liver, pancreas, spleen, kidneys, and adrenal glands. The hollow organs of the abdomen are the stomach, intestines, gallbladder, bladder, and rectum. In the thoracic cavity the heart is a hollow, muscular organ. The number of organs in any organism depends on the definition used. By one widely adopted definition, 79 organs have been identified in the human body.
  • 6.0K
  • 14 Oct 2022
Topic Review
Tether (Cryptocurrency)
Tether (often referred to by one of its currency codes, USD₮), is an asset-backed cryptocurrency stablecoin. It was launched by the company Tether Limited Inc. in 2014. Tether Limited is owned by the Hong Kong-based company iFinex Inc., which also owns the Bitfinex cryptocurrency exchange. As of July 2022, Tether Limited has minted the USDT stablecoin on ten protocols and blockchains. Tether is described as a stablecoin because it was originally designed to be valued at USD $1.00, with Tether Limited maintaining USD $1.00 of asset reserves for each USDT issued.
  • 6.0K
  • 16 Nov 2022
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