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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.
  • 13.3K
  • 23 Mar 2021
Topic Review
Wearable Devices for Stroke Prediction
Stroke ranks as one of the top first leading causes of death and disability worldwide, particularly for the most populous countries in Asia, Europe, and North America. The emerging wearable devices intended to monitor the physiological parameters, and the growth of machine learning applied to predict diseases, are promising solutions to prevent stroke and eventually predict stroke risk.
  • 13.3K
  • 30 Sep 2021
Topic Review
Morphology of Aspergillus flavus
This entry aimed to morphologically characterize and determine the aflatoxigenic and non-aflatoxigenic Aspergillus flavus isolates. Macromorphological characteristics were determined by observing the colony color and texture, while the micromorphological characteristics were determined by examining the spore color, size, structure, conidiophore structure, and vesicle shape. The production of aflatoxin was determined by direct visualization of the UV fluorescence of A. flavus colonies on CCA. Aflatoxin was qualitatively detected in 18 (45%) isolates of A. flavus using UV fluorescence screening while the remaining 22 (55%) isolates did not exhibit any aflatoxin production. 
  • 13.3K
  • 30 Aug 2021
Topic Review
Interspecific and Intergeneric Hybridization
Interspecific hybridization occurs when crosses are made between different cultivated species belonging to the same genus. In contrast, the outcome of the combination of a distinct genus (cultivated species with their wild relatives) is known as intergeneric hybridization. These two approaches are the critical driving force in generating a different combination of hybrid lines, such as synthetic amphiploid lines, alloplasmic lines, and alien gene introgression lines, which act as a source of variation that leads to a broadening of the genetic variability and diversity of desired traits for crop improvement. However, the success rate of interspecific and intergeneric hybridization is comparatively low compared to intraspecific hybridization due to cross-incompatibilities mainly related to pre- and post-fertilization barriers. To overcome these challenges, in vitro techniques utilizing somatic hybridization or embryo rescue came into the picture and have proven to be the best alternative. Several embryo rescue techniques such as embryo culture, ovary culture, ovule culture, anther culture, and protoplast culture protect embryos from successful hybridization and from premature abortion. Due to the genomic shock, this successful hybridization induces genetic and epigenetic modification at the early stages (zygote formation and development) of hybrids and successive generations. Embryo rescue techniques such as immature embryo culture were used to develop an interspecific hybrid ACC between B. napus ‘Zhongshuang 9’ and B. oleracea ‘6m08.
  • 13.3K
  • 16 Sep 2022
Topic Review
Bose Wave System
Bose Corporation's Wave Music Systems are table top audio systems which were first released in 1984. Various Wave systems comprise CD players, DAB tuners and inputs for computer sources, and in addition most models contain an AM/FM tuner. Wave systems use a folded waveguide (a series of passages from the speaker driver to the speaker grill), in an attempt to replicate sound from larger systems in a compact design. Bose claims the waveguide "produces full, clear stereo sound from a small enclosure by guiding air through two 26” folded wave guides". In 1987, Amar G. Bose and William R. Short won the Intellectual Property Owners Education Foundation's Inventor of the Year award for the waveguide loudspeaker system.
  • 13.3K
  • 20 Oct 2022
Topic Review
Conjugal Dictatorship
A "conjugal dictatorship" is the unofficial phrase which is used to denote the rule of Philippines president and dictator Ferdinand Marcos and his wife Imelda and it is also used to describe a type of family dictatorship. It originated in a book titled The Conjugal Dictatorship of Ferdinand Marcos and Imelda Marcos by Primitivo Mijares that was written in 1976 within a decade after the proclamation of martial law.
  • 13.3K
  • 04 Nov 2022
Topic Review
Root-Finding Algorithm
In mathematics and computing, a root-finding algorithm is an algorithm for finding zeroes, also called "roots", of continuous functions. A zero of a function f, from the real numbers to real numbers or from the complex numbers to the complex numbers, is a number x such that f(x) = 0. As, generally, the zeroes of a function cannot be computed exactly nor expressed in closed form, root-finding algorithms provide approximations to zeroes, expressed either as floating point numbers or as small isolating intervals, or disks for complex roots (an interval or disk output being equivalent to an approximate output together with an error bound). Solving an equation f(x) = g(x) is the same as finding the roots of the function h(x) = f(x) – g(x). Thus root-finding algorithms allow solving any equation defined by continuous functions. However, most root-finding algorithms do not guarantee that they will find all the roots; in particular, if such an algorithm does not find any root, that does not mean that no root exists. Most numerical root-finding methods use iteration, producing a sequence of numbers that hopefully converge towards the root as a limit. They require one or more initial guesses of the root as starting values, then each iteration of the algorithm produces a successively more accurate approximation to the root. Since the iteration must be stopped at some point these methods produce an approximation to the root, not an exact solution. Many methods compute subsequent values by evaluating an auxiliary function on the preceding values. The limit is thus a fixed point of the auxiliary function, which is chosen for having the roots of the original equation as fixed points, and for converging rapidly to these fixed points. The behaviour of general root-finding algorithms is studied in numerical analysis. However, for polynomials, root-finding study belongs generally to computer algebra, since algebraic properties of polynomials are fundamental for the most efficient algorithms. The efficiency of an algorithm may depend dramatically on the characteristics of the given functions. For example, many algorithms use the derivative of the input function, while others work on every continuous function. In general, numerical algorithms are not guaranteed to find all the roots of a function, so failing to find a root does not prove that there is no root. However, for polynomials, there are specific algorithms that use algebraic properties for certifying that no root is missed, and locating the roots in separate intervals (or disks for complex roots) that are small enough to ensure the convergence of numerical methods (typically Newton's method) to the unique root so located.
  • 13.3K
  • 14 Oct 2022
Topic Review
Plastic Sand as a Construction Material
Plastic waste pollution poses a serious environmental concern. At the same time, the cement industry is among the biggest sources of CO2 emissions, which poses another environmental challenge. Plastic sand bricks could be a workable solution for combating issues related to solid waste. The compressive strength decreased with increasing ratios of plastic to sand. Plastic sand bricks weighed less than the conventional bricks.
  • 13.2K
  • 10 Jun 2022
Topic Review
Interfaith Marriage
Interfaith marriage, sometimes called a "mixed marriage", is marriage between spouses professing different religions. Although interfaith marriages are most often contracted as civil marriages, in some instances they may be contracted as a religious marriage. This depends on religious doctrine of the two party's religions; some of which prohibit interfaith marriage, but others allow it in limited circumstances. Several major religions are mute on the issue, and still others allow it with requirements for ceremony and custom. For ethno-religious groups, resistance to interfaith marriage may be a form of self-segregation. In an interfaith marriage, each partner typically adheres to their own religion, but an important point is in what faith the children will be raised.
  • 13.2K
  • 25 Oct 2022
Topic Review
List of 2.4 GHz Radio Use
There are several uses of the 2.4 GHz band. Interference may occur between devices operating at 2.4 GHz. This article details the different users of the 2.4 GHz band, how they cause interference to other users and how they are prone to interference from other users.
  • 13.2K
  • 07 Nov 2022
Topic Review
Toyota Allion
The Toyota Allion (Japanese: トヨタ・アリオン, Toyota Arion) and its twin the Toyota Premio (Japanese: トヨタ・プレミオ, Toyota Puremio) are sedans sold in Japan since 2001 by Toyota. The sedans are designated as a compact car by Japanese dimension regulations and the exterior dimensions do not change with periodic updates. The Allion replaced the Carina, a model that first appeared in 1970. The Carina ED, a four-door hardtop coupe that appeared in 1985, was replaced by the Brevis, which was briefly available with the Allion until 2007. Unlike Toyota's other vehicles, the Allion and Premio are not exported, and are exclusively sold in Japan only. The Premio is the successor of the Corona which first appeared in 1957. The Corona EXiV, a four-door hardtop coupe that appeared in 1989, was replaced by the Progrès, which was also briefly available with the Premio until 2007. The Allion is exclusive to Japanese Toyota dealerships Toyota Store as a smaller companion to the Crown, while the Premio is exclusive to Toyopet Store locations, as a smaller companion to the Mark X. Both cars are related to the Avensis, which is an imported five-door liftback from Europe, available at all Japanese dealership locations. The Camry, which is the largest car exclusive to Toyota Corolla Store locations, is slightly larger, and based on appearance packages, offers the same luxury or performance features found in the Allion or Premio. The name "Allion" is created based on the phrase "all-in-one", while "Premio" is a play on words for "premium". Mechanically, they are identical to the Avensis which is exported new internationally as well as sold in Japan. The Allion/Premio are only offered as 4-door sedans, while the Avensis is available only as a five-door liftback. The first generation Premio is an upscale, luxurious sedan in comparison to the Allion, which has a more youthful, sporting nature. Wood trim and chrome accents gives the Premio an elegant look while the Allion considered to be a sporty or executive type car. Appearance modification options made for the first generation Allion are not made or marketed for the Premio. The second generation cars share the interior appearances and optional equipment, with exterior visual differences. Three options packages are offered with the three different engines offered, coupled with the choice of front- or four-wheel drive, thereby giving Japanese buyers options as to which annual road tax obligation they are willing to pay.
  • 13.2K
  • 30 Nov 2022
Topic Review
Tetrapod
Tetrapods (/ˈtɛtrəˌpɒdz/; from grc τετρα- (tetra-) 'four', and πούς (poús) 'foot') are four-limbed vertebrate animals constituting the superclass Tetrapoda (/tɛˈtrɒpədə/). It includes extant and extinct amphibians, reptiles (including dinosaurs and therefore birds), and synapsids (including mammals). Tetrapods evolved from a group of animals known as the Tetrapodomorpha which, in turn, evolved from ancient lobe-finned (sarcopterygian) fish around 390 million years ago in the middle Devonian period; their forms were transitional between lobe-finned fishes and the four-limbed tetrapods. Limbed vertebrates (tetrapods in the broad sense of the word) are first known from Middle Devonian trackways, and body fossils became common near the end of the Late Devonian but these were all aquatic. The first crown-tetrapods (last common ancestors of extant tetrapods capable of terrestrial locomotion) appeared by the very early Carboniferous, 350 million years ago. The specific aquatic ancestors of the tetrapods and the process by which they colonized Earth's land after emerging from water remains unclear. The change from a body plan for breathing and navigating in water to a body plan enabling the animal to move on land is one of the most profound evolutionary changes known. Tetrapods have numerous anatomical and physiological features that are distinct from their aquatic ancestors. These include the structure of the head for feeding and breathing, limb girdles and digits for locomotion, eyes for seeing, ears for hearing, and the heart and lungs for gas circulation and exchange outside water. The first tetrapods (stem) or "fishapods" were primarily aquatic. Modern amphibians, which evolved from earlier groups, are generally semiaquatic; the first stage of their lives is as fish-like tadpoles, and later stages are partly terrestrial and partly aquatic. However, most tetrapod species today are amniotes, most of which are terrestrial tetrapods whose branch evolved from earlier tetrapods early in the Late Carboniferous. The key innovation in amniotes over amphibians is the amnion, which enables the eggs to retain their aqueous contents on land, rather than needing to stay in water. (Some amniotes later evolved internal fertilization, although many aquatic species outside the tetrapod tree had evolved such before the tetrapods appeared, e.g. Materpiscis.) Some tetrapods, such as snakes and caecilians, have lost some or all of their limbs through further speciation and evolution; some have only concealed vestigial bones as a remnant of the limbs of their distant ancestors. Others returned to being amphibious or otherwise living partially or fully aquatic lives, the first during the Carboniferous period, others as recently as the Cenozoic. One group of amniotes diverged into the reptiles, which includes lepidosaurs, dinosaurs (which includes birds), crocodilians, turtles, and extinct relatives; while another group of amniotes diverged into the mammals and their extinct relatives. Amniotes include the tetrapods that further evolved for flight—such as birds from among the dinosaurs, pterosaurs from the archosaurs, and bats from among the mammals.
  • 13.2K
  • 04 Nov 2022
Topic Review
Omni-Man
Omni-Man (Nolan Grayson) is a fictional character in the Image Universe, created by writer Robert Kirkman and artist Cory Walker (with Ryan Ottley) as an expansion of a character concept created by Alan Moore and Chris Sprouse. Omni-Man is the father of Invincible and a member of the Viltrumite race, a humanoid species of extraterrestrial origin who possess immense powers, working as a superhero on Earth. As is customary for males of his species, Omni-Man sports a large moustache. Omni-Man appears in Supreme, Invincible, Noble Causes, and Dynamo 5. In the Invincible television series, Omni-Man is voiced by J. K. Simmons.
  • 13.2K
  • 14 Nov 2022
Topic Review
Mobile Technology in Tourism
The influence of mobile technology on tourism is very significant. With the support of mobile-related devices (smartphones, glasses, or other wearable devices), technology, data and services, multiple travel concepts, and travel modes including mobile tourism, smart tourism, e-tourism, and sustainable tourism have emerged or developed further. Mobile technology is touted as the next technology wave that can fundamentally change tourism and hotels. Moreover, mobile technology is playing an increasing role in the travel experience, and increasing travel research is concentrated in this field. Research findings show that, first, the research of mobile technology in tourism can be divided into three phases and to a certain extent is synchronized with the development of mobile technology. Second, in the area of social sciences, the research of mobile technology in tourism needs further exploration, which must refer to related research in the areas of Transportation and IT to expand the perspective of research. Top journal analysis, journal co-citation analysis, author co-citation analysis, and collaboration network analysis reveal the most representative journals, authors, institutions, and countries/regions in this research field. This finding provides a valuable reference for scholars in this field. Additionally, this research also grasped the hot and cutting-edge topics in this field through the analysis of keywords in this field. Finally, the clustering of co-citation references presents the knowledge base of mobile technology research in the tourism field: mobile technology, travel mode, mobile instrument, travel behavior research, mobile applications, and geo-based technology.
  • 13.2K
  • 28 Sep 2020
Topic Review
Primary Socialisation
Primary socialization in sociology is the period early in a person's life during which they initially learn and build themselves through experiences and interactions around them. This process starts at home through the family, in which one learns what is or is not accepted in society, social norms, and cultural practices that eventually one is likely to take up. Primary socialization through the family teaches children how to bond, create relationships, and understand important concepts including love, trust, and togetherness. Several agents of primary socialization involve institutions such as the family, childhood friends, the educational system, and social media. All these agents influence the socialization process of a child that they build on for the rest their life. These agents are limited to people who immediately surround a person such as friends and family—but other agents, such as social media and the educational system have a big influence on people as well. The media is an influential agent of socialization because it can provide vast amounts of knowledge about different cultures and society. It is through these processes that children learn how to behave in public versus at home, and eventually learn how they should behave as people under different circumstances; this is known as secondary socialization. A vast variety of people have contributed to the theory of primary socialization, of those including Sigmund Freud, George Herbert Mead, Charles Cooley, Jean Piaget and Talcott Parsons. However, Parson's theories are the earliest and most significant contributions to socialization and cognitive development.
  • 13.2K
  • 18 Nov 2022
Topic Review
Aether (Classical Element)
According to ancient and medieval science, aether (/ˈiːθər/), also spelled æther, aither, or ether and also called quintessence, is the material that fills the region of the universe above the terrestrial sphere. The concept of aether was used in several theories to explain several natural phenomena, such as the traveling of light and gravity. In the late 19th century, physicists postulated that aether permeated all throughout space, providing a medium through which light could travel in a vacuum, but evidence for the presence of such a medium was not found in the Michelson–Morley experiment, and this result has been interpreted as meaning that no such luminiferous aether exists.
  • 13.2K
  • 02 Oct 2022
Topic Review
Abrasive Water-Jet Machining
Abrasive water jet machining (AWJM) is a very useful non-conventional machining for the cutting of dissimilar materials at once. It is a flexible process that generates low thermal damage to the machined surface as there is no continuous tool-material con- tact along the machining process. Compared to conventional processes such as milling, abrasive particles are used in water jet machining. These particles have cutting edges that allow the machining of the material by overlapping of small impacts that deform the material. At each instant, a quantity of abrasive particles travels in the water jet in order to perform the cut.
  • 13.1K
  • 24 Feb 2021
Topic Review
LifePower
LifePower, (LP), is an Applied Spiritual Philosophy that attempts to improve the lives of people whilst focusing on the personal life span, using and applying a variety of tools and exercises. LP focuses on the power of the self, in the relief of suffering from past traumatic experiences and seeks to meet a high level of consciousness, communication and serenity. It consists of several techniques as well as practices, called “drills” and draws on so-called 'Listening Processes'. The LP philosophy´ was founded and created by Dani Lemberger after he studied in-depth general philosophies on life, self and existence which in combination with studying Ron Hubbard´s philosophy, led him to develop the LifePower philosophy. LifePower focuses on the power of the self, in the relief of suffering from past traumatic experiences and seeks to meet a high level of consciousness, communication and serenity. It is based on the idea, that the human being is an eternal spirit. The philosophy founder claims that by applying it, a person can enhance their abilities, attain and gain personal power to create an enjoyable and meaningful life for themselves.
  • 13.1K
  • 27 Oct 2022
Topic Review
Saraswati
Saraswati (Sanskrit: सरस्वती, IAST: Sarasvatī) is the Hindu goddess of knowledge, music, art, speech, wisdom, and learning. She is a part of the tridevi of Saraswati, Lakshmi, and Parvati. All the three equal forms unite with the trimurti of Brahma, Vishnu, and Shiva to create, maintain, and regenerate the Universe, respectively. The earliest known mention of Saraswati as a goddess is in the Rigveda. She has remained significant as a goddess from the Vedic period through modern times of Hindu traditions. She is generally shown to have four arms, holding a book, a rosary, a water pot and a musical instrument called Veena. Each of these items have symbolic meaning in Hinduism. Some Hindus celebrate the festival of Vasant Panchami (the fifth day of spring, and also known as Saraswati Puja and Saraswati Jayanti in so many parts of India) in her honour, and mark the day by helping young children learn how to write the letters of the alphabet on that day. The Goddess is also revered by believers of the Jain religion of west and central India, as well as some Buddhist sects.
  • 13.1K
  • 05 Dec 2022
Topic Review
Free-Space Optical Communication
Fast communication is of high importance. Recently, increased data demand and crowded radio frequency spectrum have become crucial issues. Free-Space Optical Communication (FSOC) has diametrically changed the way people exchange information. As an alternative to wire communication systems, it allows efficient voice, video, and data transmission using a medium like air. Due to its large bandwidth, FSOC can be used in various applications and has therefore become an important part of our everyday life. The main advantages of FSOC are a high speed, cost savings, compact structures, low power, energy efficiency, a maximal transfer capacity, and applicability. The rapid development of the high-speed connection technology allows one to reduce the repair downtime and gives the ability to quickly establish a backup network in an emergency. Unfortunately, FSOC is susceptible to disruption due to atmospheric conditions or direct sunlight. Here, we briefly discuss Free-Space Optical Communication from mirrors and optical telegraphs to modern wireless systems and outline the future development directions of optical communication.
  • 13.1K
  • 11 Nov 2020
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