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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).
  • 3.8K
  • 20 Oct 2022
Topic Review
Agency in Work Organisations
The entry deals with agency in work organisations. By agency is meant here in what ways and to what extent individuals direct their actions with their own choices and to what extent external factors influence and determine their actions. The entry focuses on constraints set and resources provided by work organisations for agency. Further, the entry gives research examples of methods to support individual agency and at the same time to redistribute agency among the stakeholders.
  • 3.8K
  • 02 Dec 2021
Topic Review
Thread Protocol
The increasing demand for Internet of Things (IoT) applications has resulted in vast amounts of data, requiring the utilization of big data analytics. The integration of big data analytics in IoT-based smart cities can greatly benefit from the development of wireless communication protocols, among which the Thread protocol has emerged as a promising option. Thread is IEEE 802.15.4 based and has advanced capabilities like mesh networking, IPv6 support, and multiple gateways providing no single point of failure.
  • 3.8K
  • 14 Jul 2023
Topic Review
Reactive Oxygen Species in Macrophages
Reactive oxygen species (ROS) are a chemically defined group of reactive molecules derived from molecular oxygen. ROS are involved in a plethora of processes in cells in all domains of life, ranging from bacteria, plants and animals, including humans. The importance of ROS for macrophage-mediated immunity is unquestioned. Their functions comprise direct antimicrobial activity against bacteria and parasites as well as redox-regulation of immune signaling and induction of inflammasome activation.
  • 3.8K
  • 10 May 2021
Topic Review
Cellulose and Cellulose Derivatives
Among the biomaterials, cellulose is the most abundant, cheap, sustainable, chemical reactive and modifiable natural macromolecular compound on the Earth. It is a carbohydrate homopolymer, which is composed of repeating long linear chains of β-anhydro-D-glucopyranose units, linked together by an ether bond between -OH group of C4, and the C1 carbon atom, via a β-1,4-glycosidic bond.
  • 3.8K
  • 10 Feb 2023
Topic Review Peer Reviewed
Inward FDI: Characterizations and Evaluation
Foreign direct investment can be defined as an investment made by an entity (usually a company) incorporated in a home country in the business interests of a host country, in the form of either establishing new business operations or acquiring controlling interest in existing business assets. Foreign direct investment is expected to meet the following characteristics: (1) the capital movement is typically accompanied by further technological, material, information, financial or personnel flows; (2) the foreign direct investor effectively controls facilities abroad; and (3) the investor has a long-term interest in the host country.
  • 3.8K
  • 13 Apr 2022
Topic Review
Shuttle–Mir Program
The Shuttle–Mir Program was a collaborative space program between Russia and the United States, which involved American Space Shuttles visiting the Russian space station Mir, Russian cosmonauts flying on the shuttle, and an American astronaut flying aboard a Soyuz spacecraft to engage in long-duration expeditions aboard Mir. The project, sometimes called "Phase One", was intended to allow the United States to learn from Russian experience with long-duration spaceflight and to foster a spirit of cooperation between the two nations and their space agencies, the US National Aeronautics and Space Administration (NASA) and the Russian Federal Space Agency (Roskosmos). The project helped to prepare the way for further cooperative space ventures; specifically, "Phase Two" of the joint project, the construction of the International Space Station (ISS). The program was announced in 1993, the first mission started in 1994 and the project continued until its scheduled completion in 1998. Eleven Space Shuttle missions, a joint Soyuz flight and almost 1000 cumulative days in space for American astronauts occurred over the course of seven long-duration expeditions. During the four-year program, many firsts in spaceflight were achieved by the two nations, including the first American astronaut to launch aboard a Soyuz spacecraft, the largest spacecraft ever to have been assembled at that time in history, and the first American spacewalk using a Russian Orlan spacesuit. The program was marred by various concerns, notably the safety of Mir following a fire and a collision, financial issues with the cash-strapped Russian Space Program and worries from astronauts about the attitudes of the program administrators. Nevertheless, a large amount of science, expertise in space station construction and knowledge in working in a cooperative space venture was gained from the combined operations, allowing the construction of the ISS to proceed much more smoothly than would have otherwise been the case.
  • 3.8K
  • 19 Oct 2022
Topic Review
Prime Time Access Rule (US)
The Prime Time Access Rule (PTAR) was a broadcasting regulation that was instituted in the United States by the Federal Communications Commission (FCC) in 1970 to restrict the amount of network programming that a local television station either owned-and-operated or affiliated with a television network can air during "prime time". This rule was repealed by the FCC in 1996.
  • 3.8K
  • 09 Nov 2022
Topic Review
Urban Land Use Planning
Urbanization is persistent globally and has increasingly significant spatial and environmental consequences. It is especially challenging in developing countries due to the increasing pressure on the limited resources, and damage to the bio-physical environment.
  • 3.8K
  • 13 Oct 2021
Topic Review
Videos Data Augmentation for Deep Learning Models
In most Computer Vision applications, Deep Learning models achieve state-of-the-art performances. One drawback of Deep Learning is the large amount of data needed to train the models. Unfortunately, in many applications, data are difficult or expensive to collect. Data augmentation can alleviate the problem, generating new data from a smaller initial dataset. Geometric and color space image augmentation methods can increase accuracy of Deep Learning models but are often not enough. More advanced solutions are Domain Randomization methods or the use of simulation to artificially generate the missing data. Data augmentation algorithms are usually specifically designed for single images. Most recently, Deep Learning models have been applied to the analysis of video sequences.
  • 3.8K
  • 25 Mar 2022
Topic Review
Fragment Identifier
In computer hypertext, a fragment identifier is a string of characters that refers to a resource that is subordinate to another, primary resource. The primary resource is identified by a Uniform Resource Identifier (URI), and the fragment identifier points to the subordinate resource. The fragment identifier introduced by a hash mark # is the optional last part of a URL for a document. It is typically used to identify a portion of that document. The generic syntax is specified in RFC 3986. The hash-mark separator in URIs is not part of the fragment identifier.
  • 3.8K
  • 30 Nov 2022
Topic Review
Poliomyelitis
Poliomyelitis, often called polio or infantile paralysis, is an infectious disease caused by the poliovirus. In about 0.5 percent of cases there is muscle weakness resulting in an inability to move. This can occur over a few hours to a few days. The weakness most often involves the legs but may less commonly involve the muscles of the head, neck and diaphragm. Many people fully recover. In those with muscle weakness about 2 to 5 percent of children and 15 to 30 percent of adults die. Another 25 percent of people have minor symptoms such as fever and a sore throat and up to 5 percent have headache, neck stiffness and pains in the arms and legs. These people are usually back to normal within one or two weeks. In up to 70 percent of infections there are no symptoms. Years after recovery post-polio syndrome may occur, with a slow development of muscle weakness similar to that which the person had during the initial infection. Poliovirus is usually spread from person to person through infected fecal matter entering the mouth. It may also be spread by food or water containing human feces and less commonly from infected saliva. Those who are infected may spread the disease for up to six weeks even if no symptoms are present. The disease may be diagnosed by finding the virus in the feces or detecting antibodies against it in the blood. The disease only occurs naturally in humans. The disease is preventable with the polio vaccine; however, multiple doses are required for it to be effective. The US Centers for Disease Control and Prevention recommends polio vaccination boosters for travelers and those who live in countries where the disease is occurring. Once infected there is no specific treatment. In 2016, there were 37 cases of wild polio and 5 cases of vaccine-derived polio. This is down from 350,000 wild cases in 1988. In 2014 the disease was only spreading between people in Afghanistan, Nigeria, and Pakistan . In 2015 Nigeria had stopped the spread of wild poliovirus but it reoccurred in 2016. Poliomyelitis has existed for thousands of years, with depictions of the disease in ancient art. The disease was first recognized as a distinct condition by the English physician Michael Underwood in 1789 and the virus that causes it was first identified in 1908 by the Austrian immunologist Karl Landsteiner. Major outbreaks started to occur in the late 19th century in Europe and the United States. In the 20th century it became one of the most worrying childhood diseases in these areas. The first polio vaccine was developed in the 1950s by Jonas Salk. It was hoped that vaccination efforts and early detection of cases would result in global eradication of the disease by 2018.
  • 3.8K
  • 10 Nov 2022
Topic Review
Minister President (Germany)
The Minister President (Ministerpräsident) is the head of state and government in thirteen of Germany sixteen states. In the three states of Berlin, Free Hanseatic City of Bremen and Free and Hanseatic City of Hamburg the heads of the state hold different titles: In the since-1952 defunct states of Baden and Württemberg-Hohenzollern the heads of state held the title State President (Staatspräsident). Nevertheless, in Germany it is common practice, to call all sixteen heads of the states ministers president if they are referred to collectively. For example, the regular meetings of the sixteen office-holders are called Conference of Ministers President (Ministerpräsidentenkonferenz).
  • 3.8K
  • 02 Nov 2022
Topic Review
RBS-15
The RBS-15 (Robotsystem 15) is a long-range fire-and-forget surface-to-surface and air-to-surface anti-ship missile. The later version Mk. III has the ability to attack land targets as well. The missile was developed by the Swedish company Saab Bofors Dynamics.
  • 3.8K
  • 01 Dec 2022
Topic Review
Supercritical Carbon Dioxide Flow and Heat Transfer Characteristics
Supercritical carbon dioxide (SCO2) is widely used in many fields of energy and power engineering, such as nuclear reactors, solar thermal power generation systems, and refrigeration systems. In practical applications, SCO2 undergoes a cooling process significantly when it is cooled near the pseudo–critical point.
  • 3.8K
  • 08 Dec 2022
Topic Review
Maize/Sorghum as Raw Brewing Materials
Brewing is among the oldest biotechnological processes, in which barley malt and—to a lesser extent—wheat malt are used as conventional raw materials. Other cereals as corn and sorghum could also be used in  brewing.
  • 3.8K
  • 06 May 2021
Topic Review
Mimusops zeyheri
Many African countries are endowed with rich biodiversity with enormous nutritional and economic prospects, but the majority of these resources are not fully harnessed. Exploring these neglected resources, for example, the Transvaal red milkwood tree [(Mimusops zeyheri) Sond. family: Sapotaceae] is of paramount importance for food and nutritional security as well as economic prosperity. This review provides a critical appraisal of the nutritional and health benefits as well as the economic potential of Mimusops zeyheri. The plant is known for its diverse uses among rural communities. In folk medicine, the decoction from the bark and leaves of Mimusops zeyheri are used for treating wounds and ulcers, while the root is used as an infusion taken to treat candidiasis and other health issues. The nutritional profile of the fruit tree is similar to popular exotic fruits and richer in vitamin C when compared to guava and orange. Mimusops zeyheri is a rich source of vitamins, protein, and fatty acids. Based on the rich chemical pool, especially in the fruit and seeds, it has the potential to provide an accessible, readily available, and affordable enriched functional food with valuable health benefits. However, the successful exploration of Mimusops zeyheri for food security and sustainability requires multidisciplinary research. This will help achieve the envisaged food-nutrition security and poverty alleviation potential of the plant, especially among local communities.
  • 3.8K
  • 19 Nov 2020
Topic Review
Folk Music
Folk music includes traditional folk music and the genre that evolved from it during the 20th-century folk revival. Some types of folk music may be called world music. Traditional folk music has been defined in several ways: as music transmitted orally, music with unknown composers, or music performed by custom over a long period of time. It has been contrasted with commercial and classical styles. The term originated in the 19th century, but folk music extends beyond that. Starting in the mid-20th century, a new form of popular folk music evolved from traditional folk music. This process and period is called the (second) folk revival and reached a zenith in the 1960s. This form of music is sometimes called contemporary folk music or folk revival music to distinguish it from earlier folk forms. Smaller, similar revivals have occurred elsewhere in the world at other times, but the term folk music has typically not been applied to the new music created during those revivals. This type of folk music also includes fusion genres such as folk rock, folk metal, and others. While contemporary folk music is a genre generally distinct from traditional folk music, in U.S. English it shares the same name, and it often shares the same performers and venues as traditional folk music.
  • 3.8K
  • 01 Nov 2022
Biography
Albert Einstein
Albert Einstein, born on March 14, 1879, in Ulm, Germany, is widely regarded as one of the most brilliant scientists in human history. His groundbreaking contributions to physics revolutionized our understanding of the universe and earned him worldwide acclaim. Einstein's life and work remain a source of inspiration and fascination, making him an iconic figure in the realm of science and beyond
  • 3.8K
  • 21 Feb 2024
Topic Review
Low-GWP Refrigerants (Pure and Blended)
Low global warming potential (GWP) refrigerants for the next-generation air conditioning systems have been investigated with target domestic applications. High-GWP refrigerants are mostly used in climate control applications such as heating, ventilation and air conditioning (HVAC) and refrigeration systems. 
  • 3.8K
  • 15 Nov 2022
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