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Topic Review
Luminiferous Aether
Luminiferous aether or ether ("luminiferous", meaning "light-bearing") was the postulated medium for the propagation of light. It was invoked to explain the ability of the apparently wave-based light to propagate through empty space, something that waves should not be able to do. The assumption of a spatial plenum of luminiferous aether, rather than a spatial vacuum, provided the theoretical medium that was required by wave theories of light. The aether hypothesis was the topic of considerable debate throughout its history, as it required the existence of an invisible and infinite material with no interaction with physical objects. As the nature of light was explored, especially in the 19th century, the physical qualities required of an aether became increasingly contradictory. By the late 1800s, the existence of the aether was being questioned, although there was no physical theory to replace it. The negative outcome of the Michelson–Morley experiment (1887) suggested that the aether did not exist, a finding that was confirmed in subsequent experiments through the 1920s. This led to considerable theoretical work to explain the propagation of light without an aether. A major breakthrough was the theory of relativity, which could explain why the experiment failed to see aether, but was more broadly interpreted to suggest that it was not needed. The Michelson-Morley experiment, along with the blackbody radiator and photoelectric effect, was a key experiment in the development of modern physics, which includes both relativity and quantum theory, the latter of which explains the particle-like nature of light.
  • 8.8K
  • 17 Oct 2022
Topic Review
JTD Engine
Multijet is Fiat Chrysler Automobiles' term for its current common rail direct injection turbodiesel engine range. Most of the Fiat, Alfa Romeo, Lancia range as well as certain Chrysler, RAM Trucks, Jeep and Maserati vehicles are equipped with Multijet engines. Ownership of some Fiat Multijet designs is shared with General Motors as part of a settlement of the failed merger between the two auto conglomerates. GM Powertrain Torino group in Turin, Italy manages their interest in these engines. Some PSA Peugeot Citroën diesel engines are also rebadged JTD units, and vice versa. Fiat's common rail diesel engine is also known as JTD, an initialism of Jet Turbo Diesel.
  • 8.8K
  • 13 Oct 2022
Topic Review
Thin-Film Dip-Coating Methods
Coating is the way of incorporating a thin coating of material into a substrate by deposition in either the liquid phase (solution) or the solid phase (powder or nanoparticles), dip-Coating is one of them.
  • 8.8K
  • 10 Aug 2022
Topic Review
Nature-inspired optimization algorithms
Over previous decades, many nature-inspired optimization algorithms (NIOAs) have been proposed and applied due to their importance and significance. Some survey studies have also been made to investigate NIOAs and their variants and applications. However, these comparative studies mainly focus on one single NIOA, and there lacks a comprehensive comparative and contrastive study of the existing NIOAs.
  • 8.8K
  • 11 Nov 2021
Topic Review
Shopping Cart
A shopping cart (American English) or trolley (British English), also known by a variety of other names, is a cart supplied by a shop, especially supermarkets, for use by customers inside the shop for transport of merchandise to the checkout counter during shopping. In many cases customers can then also use the cart to transport their purchased goods to their vehicles, but some carts are designed to prevent them from leaving the shop. In many places in the United States and the United Kingdom , customers are allowed to leave the carts in designated areas within the parking lot, and store personnel will return the carts to the storage area. In many continental European premises, however, coin- (or token-) operated locking mechanisms are provided to encourage shoppers to return the carts to the correct location after use. Studies have shown that it is advisable for shoppers to sanitize the handles and basket areas prior to handling them or filling them with groceries due to high levels of bacteria that typically live on shopping carts. This is due to the carts having a high level of exposure to the skin flora of previous users.
  • 8.8K
  • 22 Nov 2022
Topic Review
Anthroponotic Disease
Reverse zoonosis, also known as zooanthroponosis, and sometimes anthroponosis (Greek zoon "animal", anthropos "man", nosos "disease"), refers to pathogens reservoired in humans that are capable of being transmitted to other non-human animals.
  • 8.8K
  • 28 Oct 2022
Topic Review
Acer Aspire Laptops
Acer Aspire (stylized as Λspire or ΛSPIRE) is a series of personal computers by Acer Inc. aimed at the casual household user or for small business use. The Aspire series covers both desktop computers and laptops. Acer developed the series in order to cover from essentials to high performances. Many of the Aspire laptops, such as model 8920G, have built in Blu-ray drives, 5.1 audio outputs and transflective displays. Acer was the first to include these drives in laptops. Most Aspire laptops have water-resistant screens, such as the 1410 and the 5741 Z. In 2007, Acer introduced the Gemstone series that marked a milestone in the Acer Aspire line. As with many Windows laptops, different models may have different specification in different parts of the world.
  • 8.8K
  • 20 Oct 2022
Topic Review
Maharashtra Energy System
The demand for energy across the world has been increasing in recent years due to the rapid growth of the population, including in India. This work examined the progress of non-conventional energy in Maharashtra state in detail.
  • 8.8K
  • 28 Oct 2020
Topic Review
Spark Gap
A spark gap consists of an arrangement of two conducting electrodes separated by a gap usually filled with a gas such as air, designed to allow an electric spark to pass between the conductors. When the potential difference between the conductors exceeds the breakdown voltage of the gas within the gap, a spark forms, ionizing the gas and drastically reducing its electrical resistance. An electric current then flows until the path of ionized gas is broken or the current reduces below a minimum value called the "holding current". This usually happens when the voltage drops, but in some cases occurs when the heated gas rises, stretching out and then breaking the filament of ionized gas. Usually, the action of ionizing the gas is violent and disruptive, often leading to sound (ranging from a snap for a spark plug to thunder for a lightning discharge), light and heat. Spark gaps were used historically in early electrical equipment, such as spark gap radio transmitters, electrostatic machines, and X-ray machines. Their most widespread use today is in spark plugs to ignite the fuel in internal combustion engines, but they are also used in lightning arresters and other devices to protect electrical equipment from high-voltage transients.
  • 8.8K
  • 08 Oct 2022
Topic Review
Vegetation Optical Depth
The vegetation optical depth (VOD) parameterizes the extinction (attenuation & scattering) effects due to the vegetation affecting the microwave radiations propagating through the vegetation canopy. It is retrieved from both passive and active microwave remotely sensed observations. It is related almost linearly to the vegetation water content and indirectly to vegetation water status and biomass. It has been retrieved from several satellites operating at different frequencies and provides a long-term record of the vegetation dynamics over land surfaces since 1978. VOD is complementary to classically used vegetation indices derived from multi-spectral images but it is less affected by sun illumination and atmospheric effects than optical vegetation indices.
  • 8.8K
  • 27 Nov 2020
Topic Review
Liberal Socialism
Liberal socialism is a socialist political philosophy that incorporates liberal principles. Liberal socialism does not have the goal of completely abolishing capitalism and replacing it with socialism, but it instead supports a mixed economy that includes both private property and social ownership in capital goods. Although liberal socialism unequivocally favors a mixed market economy, it identifies legalistic and artificial monopolies to be the fault of capitalism and opposes an entirely unregulated economy. It considers both liberty and equality to be compatible and mutually dependent on each other. Principles that can be described as liberal socialist are based on the works of philosophers such as John Stuart Mill, Eduard Bernstein, John Dewey, Carlo Rosselli, Norberto Bobbio, Chantal Mouffe and Karl Polanyi. Other important liberal socialist figures include Guido Calogero, Piero Gobetti, Leonard Hobhouse, John Maynard Keynes and R. H. Tawney. To Polanyi, liberal socialism's goal was overcoming exploitative aspects of capitalism by expropriation of landlords and opening to all the opportunity to own land. Liberal socialism has been particularly prominent in British and Italian politics. Liberal socialism’s seminal ideas can be traced to John Stuart Mill, who theorised that capitalist societies should experience a gradual process of socialisation through worker-controlled enterprises, coexisting with private enterprises. Mill rejected centralised models of socialism that could discourage competition and creativity, but he argued that representation is essential in a free government and democracy could not subsist if economic opportunities were not well distributed, therefore conceiving democracy not just as form of representative government, but as an entire social organisation.
  • 8.8K
  • 01 Dec 2022
Topic Review
Aarne–Thompson Classification Systems
The Aarne–Thompson classification systems are indices used to classify folktales: the Aarne–Thompson Motif-Index (catalogued by alphabetical letters followed by numerals), the Aarne–Thompson Tale Type Index (cataloged by AT or AaTh numbers), and the Aarne–Thompson–Uther classification system (developed in 2004 and cataloged by ATU numbers). They are named after their authors, Antti Aarne, Stith Thompson, and Hans-Jörg Uther. The indices are used in folkloristics to organize, classify, and analyze folklore narratives and are essential tools for folklorists, as Alan Dundes explained in 1997 about the first two indices, "the identification of folk narratives through motif and/or tale type numbers has become an international sine qua non among bona fide folklorists".
  • 8.8K
  • 05 Dec 2022
Topic Review
Transwiki: Multiregional Origin of Modern Humans
The multiregional hypothesis is a scientific model that provides an explanation for the pattern of human evolution. The hypothesis holds that humans first arose near the beginning of the Pleistocene two million years ago and subsequent human evolution has been within a single, continuous human species. This species encompasses archaic human forms such as Homo erectus and Neanderthals as well as modern forms, and evolved worldwide to the diverse populations of modern Homo sapiens sapiens. The theory contends that humans evolve through a combination of adaptation within various regions of the world and gene flow between those regions. Proponents of multiregional origin point to fossil and genomic data and continuity of archaeological cultures as support for their hypothesis. The primary alternative hypothesis is recent African origin of modern humans, which contends that modern humans arose in Africa around 100-200,000 years ago, moving out of Africa around 50-60,000 years ago to replace archaic human forms without interbreeding.
  • 8.8K
  • 11 Nov 2022
Topic Review
Holobiont
A holobiont is an assemblage of a host and the many other species living in or around it, which together form a discrete ecological unit, though there is controversy over this discreteness. The components of a holobiont are individual species or bionts, while the combined genome of all bionts is the hologenome. The concept of the holobiont was initially defined by Dr. Lynn Margulis in her 1991 book Symbiosis as a Source of Evolutionary Innovation, though the concept has subsequently evolved since the original definition. Holobionts include the host, virome, microbiome, and other members, all of which contribute in some way to the function of the whole. Well-studied holobionts include reef-building corals and humans.
  • 8.8K
  • 14 Oct 2022
Topic Review Peer Reviewed
Road Markings and Signs in Road Safety
Due to the dynamic nature and complexity of road traffic, road safety is one of the most demanding social challenges. Therefore, contemporary road safety strategies incorporate a multidisciplinary and comprehensive approaches to address this problem and improve the safety of each individual element, i.e., the human, vehicle, and road. Traffic control devices are an important part of road infrastructure, among which road markings and road signs play a significant role. In general, road markings and signs represent basic means of communication between the road authorities and road users and, as such, provide road users with necessary information about the rules, warnings, obligations, and other information related to the upcoming situations and road alignment. The aim of this entry is to briefly present the main functions and characteristics of road markings and signs, and their role in road safety. In addition, practical issues and future trends and directions regarding road markings and signs are discussed. 
  • 8.8K
  • 21 Oct 2022
Topic Review
Rice Hulls
Rice hulls (or rice husks) are the hard protecting coverings of grains of rice. In addition to protecting rice during the growing season, rice hulls can be put to use as building material, fertilizer, insulation material, or fuel. Rice hulls are part of the chaff of the rice.
  • 8.8K
  • 10 Oct 2022
Topic Review Peer Reviewed
Affective Economy: A Theoretical Outline
The affective economy is a concept that emerged within the field of social sciences, focusing on the interplay between emotions, affects, and economic processes. It explores how emotions and affective experiences shape economic practices, consumption patterns, and the production of goods and services. In the affective economy framework, emotions are seen as not merely individual but deeply embedded in social and political contexts, shaping and being shaped by social structures and power dynamics. The affective economy emphasizes how emotions circulate and contribute to the construction and maintenance of social orders, impacting economic actions. It acknowledges the profound impact of emotions and affects on economic behavior. Thus, this concept sheds light on the intricate relationship between emotions and economic processes, demonstrating how affective experiences influence consumption, production, labor, financial decisions, and the overall dynamics of the market economy. It emphasizes the need for a more nuanced understanding of human behavior in economic contexts, recognizing the significance of emotions and affective responses as integral components of economic activities. This concept is connected to notions of dwelling, topophilia, and affective atmospheres, providing insights into the complexities of economic transactions in diverse cultural contexts.
  • 8.8K
  • 28 Aug 2023
Topic Review
Industry 4.0 and Sustainability
Sustainability and Industry 4.0 (I4.0) are trending concepts used in the literature on industrial processes. Industry 4.0 has been mainly addressed by the current literature from a technological perspective, overlooking sustainability challenges regarding this recent paradigm. The objective of this encyclopedia entry is to evaluate the state of the art of relations between sustainability and I4.0. The goal will be met by (1) mapping and summarizing existing research efforts, (2) identifying research agendas, (3) examining gaps and opportunities for further research. Web of Science, Scopus, and a set of specific keywords were used to select peer-reviewed papers presenting evidence on the relationship between sustainability and I4.0. To achieve this goal, it was decided to use a dynamic methodology called “systematic literature network analysis”. This methodology combines a systematic literature review approach with the analysis of bibliographic networks. Selected papers were used to build a reference framework formed by I4.0 technologies and sustainability issues. The encyclopedia entry contributes to the Sustainable Industry 4.0 reference framework with application procedures. It aims to show how I4.0 can support ideas of sustainability. The results showed that apart from a huge contribution to both concepts, many papers do not provide an insight into realization of initiatives to introduce Sustainable Industry 4.0.
  • 8.8K
  • 06 Jun 2021
Topic Review
Viroids: Definition and Features
Viroids are plant-restricted parasites that represent a remarkable model system to analyze many aspects of host-pathogen interactions at the genomic level. As the smallest known agents of infectious disease (247-401 nucleotides, nt), they have a highly structured, single-stranded circular naked and non-coding RNA genome. Although the list of known diseases caused by viroids and molecular characterization of the causative agents has expanded since they were discovered, their origin, evolution, and interaction with host genetic machinery to induce symptoms or escape the defensive system remain unclear.
  • 8.7K
  • 01 Nov 2020
Topic Review
CASC Rainbow
CASC Rainbow (Cai Hong, abbreviated as CH) is a series of unmanned aerial vehicles (UAVs) developed by the China Academy of Aerospace Aerodynamics, an entity under the China Aerospace Science and Technology Corporation (CASC). The China Academy of Aerospace Aerodynamics is also known as the 11th Academy of CASC, or 701st Research Institute.
  • 8.7K
  • 17 Oct 2022
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