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Topic Review
Hydraulic Actuators
Hydraulic actuators are elements converting the energy of the working fluid into mechanical energy related to the reciprocating motion. The most frequently applied materials used in power hydraulics are described, and various surface modifications of the discussed elements, which are aimed at improving the operating parameters of actuators, are presented. The most frequently used materials for actuators elements are iron alloys. However, due to rising ecological requirements, there is a tendency to looking for modern replacements to obtain the same or even better mechanical or tribological parameters. Sealing systems are manufactured mainly from thermoplastic or elastomeric polymers, which are characterized by low friction and ensure the best possible interaction of seals with the cooperating element. In the field of surface modification, among others, the issue of chromium plating of piston rods has been discussed, which, due, to the toxicity of hexavalent chromium, should be replaced by other methods of improving surface properties.
  • 10.9K
  • 23 Mar 2021
Topic Review
Effect of COVID-19 Pandemic on the Fashion Industry
The preference for a specific fashion style proved to have an impact on the product, promotion, WOM and fashion lovers’ behavior during COVID-19. Moreover, those elements have an impact on the frequency of fashion apparel consumption. Based on these results, fashion companies can tailor their activities in line with the predominant style of their fashion apparel to improve their economic sustainability during the post-COVID-19 era. 
  • 10.9K
  • 06 May 2022
Topic Review
Georgism
Georgism, also called in modern times geoism and known historically as the single tax movement, is an economic ideology holding that, although people should own the value they produce themselves, the economic rent derived from land – including from all natural resources, the commons, and urban locations – should belong equally to all members of society. Developed from the writings of American economist and social reformer Henry George, the Georgist paradigm seeks solutions to social and ecological problems, based on principles of land rights and public finance which attempt to integrate economic efficiency with social justice. Georgism is concerned with the distribution of economic rent caused by land ownership, natural monopolies, pollution and the control of commons, including title of ownership for natural resources and other contrived privileges (e.g. intellectual property). Any natural resource which is inherently limited in supply can generate economic rent, but the classical and most significant example of land monopoly involves the extraction of common ground rent from valuable urban locations. Georgists argue that taxing economic rent is efficient, fair and equitable. The main Georgist policy recommendation is a tax assessed on land value, arguing that revenues from a land value tax (LVT) can be used to reduce or eliminate existing taxes (such as on income, trade, or purchases) that are unfair and inefficient. Some Georgists also advocate for the return of surplus public revenue to the people by means of a basic income or citizen's dividend. The concept of gaining public revenues mainly from land and natural resource privileges was widely popularized by Henry George through his first book, Progress and Poverty (1879). The philosophical basis of Georgism dates back to several early thinkers such as John Locke, Baruch Spinoza and Thomas Paine. Economists since Adam Smith and David Ricardo have observed that a public levy on land value does not cause economic inefficiency, unlike other taxes. A land value tax also has progressive tax effects. Advocates of land value taxes argue that they would reduce economic inequality, increase economic efficiency, remove incentives to underutilize urban land and reduce property speculation. Georgist ideas were popular and influential during the late 19th and early 20th century. Political parties, institutions and communities were founded based on Georgist principles during that time. Early devotees of Henry George's economic philosophy were often termed Single Taxers for their political goal of raising public revenue mainly or only from a land value tax, although Georgists endorsed multiple forms of rent capture (e.g. seigniorage) as legitimate. The term Georgism was invented later, and some prefer the term geoism as more generic.
  • 10.8K
  • 08 Nov 2022
Topic Review
Food Colorants Analysis in Foods
Color additives are used extensively in several food products, as to enhance their appearance, and their nutritional properties. They can be defined as “any substance that its intentional addition of which to a food aiming for a technological (including organoleptic) purpose in the manufacture, processing, preparation treatment, packing, packaging, transport or holding of such food results, or may be reasonably expected to result, in it or its by-products becoming a component of the food or otherwise affecting the characteristics of such foods”. Thus, hereby they are presented all the late advancements related to existing analytical methods and sample preparation methodologies, for their determination and quantification in food matrices.Furthermore, all these advancements are connected to general information about the existing natural or synthetic food colorants, along with legislative information and toxicological aspects, in order to support the importance and the need of appropriate analytical methodologies.
  • 10.8K
  • 12 Jan 2021
Topic Review
Physical Law
A physical law or a law of physics is a statement "inferred from particular facts, applicable to a defined group or class of phenomena, and expressible by the statement that a particular phenomenon always occurs if certain conditions be present." Physical laws are typically conclusions based on repeated scientific experiments and observations over many years and which have become accepted universally within the scientific community. The production of a summary description of our environment in the form of such laws is a fundamental aim of science. These terms are not used the same way by all authors. The distinction between natural law in the political-legal sense and law of nature or physical law in the scientific sense is a modern one, both concepts being equally derived from physis, the Greek word (translated into Latin as natura) for nature.
  • 10.8K
  • 01 Dec 2022
Topic Review
Germplasm Conservation
Germplasm is a valuable natural resource that provides knowledge about the genetic composition of a species and is crucial for conserving plant diversity. Germplasm protection strategies not only involve rescuing plant species threatened with extinction, but also help preserve all essential plants, on which rests the survival of all organisms. The successful use of genetic resources necessitates their diligent collection, storage, analysis, documentation, and exchange. Slow growth cultures, cryopreservation, pollen and DNA banks, botanical gardens, genetic reserves, and farmers’ fields are a few germplasm conservation techniques being employed. However, the adoption of in-vitro techniques with any chance of genetic instability could lead to the destruction of the entire substance, but the improved understanding of basic regeneration biology would, in turn, undoubtedly increase the capacity to regenerate new plants, thus expanding selection possibilities. Germplasm conservation seeks to conserve endangered and vulnerable plant species worldwide for future proliferation and development; it is also the bedrock of agricultural production. 
  • 10.7K
  • 25 Jun 2021
Topic Review
E-Government
E-government (short for electronic government) is the use of electronic communications devices, computers and the Internet to provide public services to citizens and other persons in a country or region. According to Jeong, 2007 the term consists of the digital interactions between a citizen and their government (C2G), between governments and other government agencies (G2G), between government and citizens (G2C), between government and employees (G2E), and between government and businesses/commerces (G2B). E-government delivery models can be broken down into the following categories: This interaction consists of citizens communicating with all levels of government (city, state/province, national, and international), facilitating citizen involvement in governance using information and communication technology (ICT) (such as computers and websites) and business process re-engineering (BPR). Brabham and Guth (2017) interviewed the third party designers of e-government tools in North America about the ideals of user interaction that they build into their technologies, which include progressive values, ubiquitous participation, geolocation, and education of the public. Other definitions are more away from technology as an object, to see them simply as facilitators or instruments and focus on specific changes in Public Administration issues, and in the internal transformation of a Government, is the case of the definition that established the specialist technologist Mauro D. Ríos in the paper "In search of a definition of Electronic Government", he says: "Digital Government is a new way of organization and management of public affairs, introducing positive transformational processes in management and the structure itself of the organization chart, adding value to the procedures and services provided, all through the introduction and continued appropriation of information and communication technologies as a facilitator of these transformations."
  • 10.7K
  • 08 Nov 2022
Topic Review
Electric Vehicles Adoption Scenario in Malaysia
In the roadmaps of the automotive industry, the electric vehicle (EV) is regarded as a crucial technology for the future of automotive power systems. The EV has become a top priority of major global car manufacturers and is expected to disrupt the road transportation sector. In Malaysia and Indonesia, EVs just started as an important force. However, in Malaysia, the lack of EV infrastructure, along with its strong dependency on fossil fuels, poses an enormous challenge. 
  • 10.7K
  • 05 May 2022
Topic Review
Vaginal Discharge
Vaginal discharge is a mixture of liquid, cells, and bacteria that lubricate and protect the vagina. This mixture is constantly produced by the cells of the vagina and cervix, and it exits the body through the vaginal opening. The composition, amount, and quality of discharge varies between individuals and can vary throughout the menstrual cycle and throughout the stages of sexual and reproductive development. Normal vaginal discharge may have a thin, watery consistency or a thick, sticky consistency, and it may be clear or white in color. Normal vaginal discharge may be large in volume but typically does not have a strong odor, nor is it typically associated with itching or pain. While most discharge is considered physiologic or represents normal functioning of the body, some changes in discharge can reflect infection or other pathological processes. Infections that may cause changes in vaginal discharge include vaginal yeast infections, bacterial vaginosis, and sexually transmitted infections. The characteristics of abnormal vaginal discharge vary depending on the cause, but common features include a change in color, a foul odor, and associated symptoms such as itching, burning, pelvic pain, or pain during sexual intercourse.
  • 10.7K
  • 14 Nov 2022
Topic Review
Sigma-Algebra
In mathematical analysis and in probability theory, a σ-algebra (also σ-field) on a set X is a collection Σ of subsets of X that includes the empty subset, is closed under complement, and is closed under countable unions and countable intersections. The pair (X, Σ) is called a measurable space or Borel space. A σ-algebra is a type of algebra of sets. An algebra of sets needs only to be closed under the union or intersection of finitely many subsets, which is a weaker condition. The main use of σ-algebras is in the definition of measures; specifically, the collection of those subsets for which a given measure is defined is necessarily a σ-algebra. This concept is important in mathematical analysis as the foundation for Lebesgue integration, and in probability theory, where it is interpreted as the collection of events which can be assigned probabilities. Also, in probability, σ-algebras are pivotal in the definition of conditional expectation. In statistics, (sub) σ-algebras are needed for the formal mathematical definition of a sufficient statistic, particularly when the statistic is a function or a random process and the notion of conditional density is not applicable. If X = {a, b, c, d}, one possible σ-algebra on X is Σ = { ∅, {a, b}, {c, d}, {a, b, c, d} }, where ∅ is the empty set. In general, a finite algebra is always a σ-algebra. If {A1, A2, A3, …} is a countable partition of X then the collection of all unions of sets in the partition (including the empty set) is a σ-algebra. A more useful example is the set of subsets of the real line formed by starting with all open intervals and adding in all countable unions, countable intersections, and relative complements and continuing this process (by transfinite iteration through all countable ordinals) until the relevant closure properties are achieved (a construction known as the Borel hierarchy).
  • 10.7K
  • 01 Dec 2022
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