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Topic Review
Labia
The labia are part of the female genitalia; they are the major externally visible portions of the vulva. In humans, there are two pairs of labia: the labia majora (or the outer labia) are larger and fattier, while the labia minora are folds of skin between the outer labia. The labia surround and protect the clitoris and the openings of the vagina and the urethra.
  • 26.6K
  • 28 Nov 2022
Topic Review
Shaft Mining
Shaft mining or shaft sinking is excavating a vertical or near-vertical tunnel from the top down, where there is initially no access to the bottom. Shallow shafts, typically sunk for civil engineering projects differ greatly in execution method from deep shafts, typically sunk for mining projects. When the top of the excavation is the ground surface, it is referred to as a shaft; when the top of the excavation is underground, it is called a winze or a sub-shaft. Small shafts may be excavated upwards from within an existing mine as long as there is access at the bottom, in which case they are called Raises. A shaft may be either vertical or inclined (between 45 and 90 degrees to the horizontal), although most modern mine shafts are vertical. If access exists at the bottom of the proposed shaft and ground conditions allow then raise boring may be used to excavate the shaft from the bottom up, such shafts are called borehole shafts. Shaft sinking is one of the most difficult of all development methods: restricted space, gravity, groundwater and specialized procedures make the task quite formidable. Historically mine shaft sinking has been among the most dangerous of all the mining occupations and the preserve of mining contractors called sinkers. Today shaft sinking contractors are concentrated in Canada , Germany and South Africa .
  • 26.5K
  • 17 Nov 2022
Topic Review
Gompertz Function with R
The Gompertz function is a sigmoid curve being a special case of a logistic curve. Although it was originally designed to describe mortality, it is now used in biology. For example, it is useful to describe many  phenomena such as the growth of a cancerous tumor confined to an organ without metastasis, the growth of the number of individuals in a population, e.g. prey in a Volterra-Lotka model, the germination of seeds, etc. It also models as the logistic function the growth of a colony of bacteria or in an epidemic the spread of the number of infected people. However, despite its many applications, in many cases the fitting of experimental data to the Gompertz function is not always straightforward. In this article we present a protocol that will be useful when performing the data regression to this curve using the statistical package R.
  • 26.4K
  • 07 Apr 2021
Topic Review
Divide and Rule
Divide and rule (Latin: divide et impera), or divide and conquer, in politics and sociology is gaining and maintaining power by breaking up larger concentrations of power into pieces that individually have less power than the one implementing the strategy. The use of this technique is meant to empower the sovereign to control subjects, populations, or factions of different interests, who collectively might be able to oppose its rule. Niccolò Machiavelli identifies a similar application to military strategy, advising in Book VI of The Art of War (1521) (L'arte della guerra): a Captain should endeavor with every act to divide the forces of the enemy. Machiavelli advises that this act should be achieved either by making him suspicious of his men in whom he trusted, or by giving him cause that he has to separate his forces, and, because of this, become weaker. The maxim divide et impera has been attributed to Philip II of Macedon. It was utilised by the Roman ruler Julius Caesar and the French emperor Napoleon (together with the maxim divide ut regnes). The strategy, but not the phrase, applies in many ancient cases: the example of Aulus Gabinius exists, parting the Jewish nation into five conventions, reported by Flavius Josephus in Book I, 169–170 of The Jewish War (De bello Judaico). Strabo also reports in Geographica, 8.7.3 that the Achaean League was gradually dissolved when it became part of the Roman province of Macedonia, as the Romans treated the various states differently, wishing to preserve some and to destroy others. The strategy of division and rule has been attributed to sovereigns, ranging from Louis XI of France to the House of Habsburg. Edward Coke denounces it in Chapter I of the Fourth Part of the Institutes of the Lawes of England, reporting that when it was demanded by the Lords and Commons what might be a principal motive for them to have good success in Parliament, it was answered: "Eritis insuperabiles, si fueritis inseparabiles. Explosum est illud diverbium: Divide, & impera, cum radix & vertex imperii in obedientium consensu rata sunt." [You would be invincible if you were inseparable. This proverb, Divide and rule, has been rejected, since the root and the summit of authority are confirmed by the consent of the subjects.] In a minor variation, Sir Francis Bacon wrote the phrase "separa et impera" in a letter to James I of 15 February 1615. James Madison made this recommendation in a letter to Thomas Jefferson of 24 October 1787, which summarized the thesis of The Federalist#10: "Divide et impera, the reprobated axiom of tyranny, is under certain (some) qualifications, the only policy, by which a republic can be administered on just principles." In Perpetual Peace: A Philosophical Sketch by Immanuel Kant (1795), Appendix one, Divide et impera is the third of three political maxims, the others being Fac et excusa (Act now, and make excuses later) and Si fecisti, nega (If you commit a crime, deny it). Elements of this technique involve: Historically, this strategy was used in many different ways by empires seeking to expand their territories. Immanuel Kant was an advocate of this tactic, noting that "the problem of setting up a state can be solved even by a nation of devils" so long as they possess an appropriate constitution which pits opposing factions against each other with a system of checks and balances. The concept is also mentioned as a strategy for market action in economics to get the most out of the players in a competitive market.
  • 26.4K
  • 28 Nov 2022
Topic Review
Chronology of Jesus
A chronology of Jesus aims to establish a timeline for the events of the life of Jesus. Scholars have correlated Jewish and Greco-Roman documents and astronomical calendars with the New Testament accounts to estimate dates for the major events in Jesus's life. Two main approaches have been used to estimate the year of the birth of Jesus: one based on the accounts in the Gospels of his birth with reference to King Herod's reign, and the other by subtracting his stated age of "about 30 years" when he began preaching. Most scholars, on this basis, assume a date of birth between 6 and 4 BC. Three details have been used to estimate the year when Jesus began preaching: a mention of his age of "about 30 years" during "the fifteenth year" of the reign of Tiberius Caesar, another relating to the date of the building of the Temple in Jerusalem, and yet another concerning the death of John the Baptist. Hence, scholars estimate that Jesus began preaching and gathering followers around AD 28–29. According to the three synoptic gospels Jesus continued preaching for at least one year, and according to John the Evangelist for three years. Five methods have been used to estimate the date of the crucifixion of Jesus. One uses non-Christian sources such as Josephus and Tacitus. Another works backwards from the historically well-established trial of the Apostle Paul by the Roman proconsul Gallio in Corinth in AD 51/52 to estimate the date of Paul's conversion. Both methods result in AD 36 as an upper bound to the crucifixion. Thus, scholars generally agree that Jesus was crucified between AD 30 and AD 36. Isaac Newton's astronomical method calculates those ancient Passovers (always defined by a full moon) which are preceded by a Friday, as specified by all four Gospels; this leaves two potential crucifixion dates, 7 April AD 30 and 3 April AD 33. In the lunar eclipse method, the Apostle Peter's statement that the moon turned to blood at the crucifixion (Acts of the Apostles 2:14-21) is taken to refer to the lunar eclipse of 3 April AD 33; although astronomers are discussing whether the eclipse was visible as far west as Jerusalem. Recent astronomical research uses the contrast between the synoptic date of Jesus' last Passover on the one hand with John's date of the subsequent "Jewish Passover" on the other hand, to propose Jesus' Last Supper to have been on Wednesday, 1 April AD 33 and the crucifixion on Friday 3 April AD 33.
  • 26.3K
  • 09 Nov 2022
Topic Review
Sensors for Health Monitoring
The use of wearable equipment and sensing devices to monitor physical activities, whether for well-being, sports monitoring, or medical rehabilitation, has expanded rapidly due to the evolution of sensing techniques, cheaper integrated circuits, and the development of connectivity technologies. In this scenario, this paper presents a state-of-the-art review of sensors and systems for rehabilitation and health monitoring. Although we know the increasing importance of data processing techniques, our focus was on analyzing the implementation of sensors and biomedical applications. Although many themes overlap, we organized this review based on three groups: Sensors in Healthcare, Home Medical Assistance, and Continuous Health Monitoring; Systems and Sensors in Physical Rehabilitation; and Assistive Systems.
  • 26.3K
  • 19 Feb 2021
Biography
Curtis Yarvin
Curtis Guy Yarvin (born 1973), also known by the pen name Mencius Moldbug, is an American political theorist, blogger[1] and software developer.[2] Yarvin has been described as a neoreactionary[3] and "neo-monarchist".[4][5] His ideas have been associated with the alt-right.[5][6][7] From 2007 to 2014, he authored a blog called "Unqualified Reservations", which argued that American democracy is
  • 26.2K
  • 26 Dec 2022
Topic Review
Astronomy in the Medieval Islamic World
Islamic astronomy comprises the astronomical developments made in the Islamic world, particularly during the Islamic Golden Age (9th–13th centuries), and mostly written in the Arabic language. These developments mostly took place in the Middle East, Central Asia, Al-Andalus, and North Africa, and later in the Far East and India. It closely parallels the genesis of other Islamic sciences in its assimilation of foreign material and the amalgamation of the disparate elements of that material to create a science with Islamic characteristics. These included Greek, Sassanid, and Indian works in particular, which were translated and built upon. Islamic astronomy played a significant role in the revival of Byzantine and European astronomy following the loss of knowledge during the early medieval period, notably with the production of Latin translations of Arabic works during the 12th century. Islamic astronomy also had an influence on Chinese astronomy and Malian astronomy. A significant number of stars in the sky, such as Aldebaran, Altair and Deneb, and astronomical terms such as alidade, azimuth, and nadir, are still referred to by their Arabic names. A large corpus of literature from Islamic astronomy remains today, numbering approximately 10,000 manuscripts scattered throughout the world, many of which have not been read or catalogued. Even so, a reasonably accurate picture of Islamic activity in the field of astronomy can be reconstructed.
  • 26.1K
  • 24 Nov 2022
Topic Review Video
Modular Multilevel Converters
A modular multilevel converter (MMC) is an advanced voltage source converter applicable to a wide range of medium and high-voltage applications. It has competitive advantages such as quality output performance, high modularity, simple scalability, and low voltage and current rating demand for the power switches. The generalized configuration of a three-phase MMC is comprised of a DC terminal, an AC terminal, and a converting kernel involving three phase legs. Each leg/phase has two symmetric arms referred to as the upper arm and lower arm. The upper arm and lower arm contain a group of identical submodules connected in series together with a chock inductor to suppress high-frequency components in the arm current.  The research interests of MMCs are primarily associated with the topologies, mathematical modeling, output voltage and current control, submodule balancing control, circulating current control, and modulation methods. And the incorporation of wideband gap (WBG) semiconductors are prospected to facilitate the MMC application with further advantages of high-voltage and high-power operations, low power losses, high efficiency, improved reliability, and reduced module size and cooling system.
  • 26.0K
  • 18 Aug 2021
Topic Review
Wages in Thailand
Wages in Thailand, as used here, includes all compensation paid by an employer to an employee for work done, whether based on hours worked, piece work, or fixed salary. Since wage labour is the predominant form of work, the term "wage" here refers to all forms of employee compensation. Wages are the major source of household income in Thailand,:32 although wage income distribution varies by region: Almost three-quarters of the population in Bangkok are in households that receive wage income, compared with less than half in the northern region.:30-31 During the period 2007–2014, wage income grew markedly, and then began to drop starting in 2015. (As of 2020) wage growth stagnation afflicts most occupations. Wage growth was negative in urban areas, but positive in rural areas. In the period 2007–2013, wages, farm incomes, and remittances contributed to poverty reduction; in the period 2015–2017 these were sources of rising poverty.:65
  • 26.0K
  • 07 Oct 2022
Topic Review
History of Measurement
The earliest recorded systems of weights and measures originate in the 3rd or 4th millennium BC. Even the very earliest civilizations needed measurement for purposes of agriculture, construction, and trade. Early standard units might only have applied to a single community or small region, with every area developing its own standards for lengths, areas, volumes and masses. Often such systems were closely tied to one field of use, so that volume measures used, for example, for dry grains were unrelated to those for liquids, with neither bearing any particular relationship to units of length used for measuring cloth or land. With development of manufacturing technologies, and the growing importance of trade between communities and ultimately across the Earth, standardized weights and measures became critical. Starting in the 18th century, modernized, simplified and uniform systems of weights and measures were developed, with the fundamental units defined by ever more precise methods in the science of metrology. The discovery and application of electricity was one factor motivating the development of standardized internationally applicable units.
  • 25.9K
  • 03 Nov 2022
Topic Review
TCP-based Congestion Control Algorithms
In today’s data networks, the main protocol used to ensure reliable communications is the transmission control protocol (TCP). The TCP performance is largely determined by the used congestion control (CC) algorithm, which main purpose is to avoid the congestion of the network that can be caused by a large burst of data traffic. TCP CC algorithms have evolved over the past three decades and a large number of CC algorithm variations have been developed to accommodate various communication network environments. Considering the importance of CC in communication networks, the fundamentals of the TCP as the main transport layer protocol and CC process have been explained in detail. Also, an encyclopedic overview of the most popular single-flow and multi-flow TCP CC algorithms with corresponding alternatives has been present. Future directions in the possible improvement of CC algorithms for implementation in complex heterogeneous networks composed of wired and wireless elements are lastly discussed in this encyclopedic work. 
  • 25.8K
  • 21 Jul 2021
Topic Review
Sociology
Sociology is a science with specificities that can offer a more rigorous knowledge of social reality. But what is sociology? There is a wide variety of definitions and it is not easy to define them directly. It is an extremely ambitious and broad theme of which we will make a brief presentation based on Ferreira & Serpa (2017), Serpa & Ferreira (2018), and Serpa & Ferreira (2019).
  • 25.6K
  • 30 Oct 2020
Topic Review
Pharmakon
Pharmakon, in philosophy and critical theory, is a composite of three meanings: remedy, poison, and scapegoat. The first and second senses refer to the everyday meaning of pharmacology (and to its sub-field, toxicology), deriving from the Greek source term φάρμακον (phármakon), denoting any drug, while the third sense refers to the pharmakos ritual of human sacrifice. A further sub-sense of pharmakon as remedy which is of interest to some current authors is given by the Liddell-Scott-Jones Greek–English Lexicon as "a means of producing something". In recent philosophical work, the term centers on Jacques Derrida's "Plato's Pharmacy", and the notion that writing is a pharmakon. Whereas a straightforward view on Plato's treatment of writing (in Phaedrus) suggests that writing is to be rejected as strictly poisonous to the ability to think for oneself in dialogue with others (i.e. to anamnesis), Bernard Stiegler argues that "the hypomnesic appears as that which constitutes the condition of the anamnesic"—in other words, externalised time-bound communication is necessary for original creative thought, in part because it is the primordial support of culture. Michael Rinella has written a book-length review of the pharmakon within a historical context, with an emphasis on the relationship between pharmakoi in the standard drug sense and the philosophical understanding of the term. Adrian Mróz, a Polish-American philosopher and musician, analyses its application to art and argues that pharmakon is any physical, mental, or behavioral object which can cut (techne). In other words, pharmaka are agential and responsible for changes in consciousness.
  • 25.6K
  • 07 Nov 2022
Topic Review
System Architecture for Autonomous Vehicles
Technology facilitates humans, improves productivity and leads to a better quality of life. Technological developments and automation in vehicular networks will lead to better road safety and lower congestion in present urban areas where the traditional transport system is becoming increasingly disorganised and inefficient. Therefore, the development of the intelligent transport systems (ITS) concept has been proposed, with the aim and focus on improving traffic safety and providing different services to its users. There has been considerable research in ITS resulting in significant contributions . 
  • 25.4K
  • 07 Apr 2021
Topic Review
Digital Journalism
Digital journalism also known as online journalism is a contemporary form of journalism where editorial content is distributed via the Internet as opposed to publishing via print or broadcast. What constitutes 'digital journalism' is debated by scholars. However the primary product of journalism, which is news and features on current affairs, is presented solely or in combination as text, audio, video, or some interactive forms like newsgames, and disseminated through digital media technology. Fewer barriers to entry, lowered distribution costs, and diverse computer networking technologies have led to the widespread practice of digital journalism. It has democratized the flow of information that was previously controlled by traditional media including newspapers, magazines, radio, and television. Some have asserted that a greater degree of creativity can be exercised with digital journalism when compared to traditional journalism and traditional media. The digital aspect may be central to the journalistic message and remains, to some extent, within the creative control of the writer, editor, and/or publisher.
  • 25.4K
  • 02 Dec 2022
Topic Review
Gender Differences in Work-Life Balance/Career Opportunities/Health
Although gender roles no longer clearly define who is responsible for home care and who is responsible for job duties, some research shows that the conflict between family and work life appears to be a greater problem for women than for men. For women, the relationships between career opportunities and work–life balance and between career opportunities and the perception of general health have significantly lower values compared to results from the group of men, while the perception of work–life balance affects well-being more significantly when compared to the male counterpart.
  • 25.4K
  • 21 Jun 2024
Topic Review
Close Quarters Combat
Close quarters combat (CQC) is a tactical concept that involves physical confrontation between several combatants. It can take place between military units, police/corrections and criminals, and other similar scenarios. In warfare, it usually consists of small units or teams engaging the enemy with personal weapons at very short range, up to 100 meters, from proximity hand-to-hand combat to close-quarter target negotiation with short-range firearms. In the typical close quarters combat scenario, the attackers try a very fast, violent takeover of a vehicle or structure controlled by the defenders, who usually have no easy way to withdraw. Because enemies, hostages/civilians, and fellow operators can be closely intermingled, close quarters combat demands a rapid assault and a precise application of lethal force. The operators need great proficiency with their weapons, and the ability to make split-second decisions in order to minimize accidental casualties. Criminals sometimes use close quarters combat techniques, such as in an armed robbery or jailbreak, but most of the terminology comes from training used to prepare soldiers, police/corrections, and other authorities. Therefore, much material relating to close quarters combat is written from the perspective of the authorities who must break into the stronghold where the opposing force has barricaded itself. Typical examples would be commando operations behind enemy lines and hostage rescues. Although there is considerable overlap, close quarters combat is not synonymous with urban warfare, now sometimes known by the military acronyms MOUT (military operations in urban terrain), FIBUA (fighting in built-up areas) or OBUA (Operations in Built Up Areas) in the West. Urban warfare is a much larger field, including logistics and the role of crew-served weapons like heavy machine guns, mortars, and mounted grenade launchers, as well as artillery, armor, and air support. In close quarters combat, the emphasis is on small infantry units using light, compact weapons that one person can carry and use easily in tight spaces, such as carbines, submachine guns, shotguns, pistols, knives, and bayonets. As such, close quarters combat is a tactical concept that forms a part of the strategic concept of urban warfare, but not every instance of close quarters combat is necessarily urban warfare—for example, a jungle is potentially a stage for close quarters combat.
  • 25.2K
  • 22 Nov 2022
Topic Review
Eeny, Meeny, Miny, Moe
"Eeny, meeny, miny, moe" — which can be spelled a number of ways — is a children's counting rhyme, used to select a person in games such as tag. It is one of a large group of similar rhymes in which the child who is pointed to by the chanter on the last syllable is either "chosen" or "counted out". The rhyme has existed in various forms since well before 1820, and is common in many languages with similar-sounding nonsense syllables. Since many similar counting rhymes existed earlier, it is difficult to ascertain this rhyme's exact original.
  • 25.2K
  • 12 Oct 2022
Topic Review
List of the Verified Oldest People
This is a list of the 100 verified oldest people, arranged in descending order of each individual's age in years and days. A year typically refers to a calendar year, the time between two dates of the same name. However, years can be of different lengths due to the presence or absence of a leap day within the year, or to the conversion of dates from one calendar to another. The oldest person ever whose age has been verified is Jeanne Calment (1875–1997) of France, who died at the age of 122 years, 164 days. There are six living people on this list, all of whom are women and the oldest of whom is Kane Tanaka of Japan, aged 119 years, 234 days. Since all the people on this list have lived past the age of 110, all of them have been, or still are, supercentenarians.
  • 25.1K
  • 07 Oct 2022
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