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Topic Review
Flying Ad-Hoc Networks
Unmanned aerial vehicles (UAVs), also known as drones, once centric to military applications, are presently finding their way in many civilian and commercial applications. If national legislations permit UAVs to operate autonomously, one will see the skies become populated with many small UAVs, each one performing various tasks such as mail and package delivery, traffic monitoring, event filming, surveillance, search and rescue, and other applications. Thus, advancing to multiple small UAVs from a single large UAV has resulted in a new clan of networks known as flying ad-hoc networks (FANETs). Such networks provide reliability, ease of deployment, and relatively low operating costs by offering a robust communication network among the UAVs and base stations (BS). Although FANETs offer many benefits, there also exist a number of challenges that need to be addressed; the most significant of these being the communication one.
  • 6.2K
  • 28 Feb 2022
Topic Review
Flocculus (Cerebellar)
The flocculus (Latin: tuft of wool, diminutive) is a small lobe of the cerebellum at the posterior border of the middle cerebellar peduncle anterior to the biventer lobule. Like other parts of the cerebellum, the flocculus is involved in motor control. It is an essential part of the vestibulo-ocular reflex, and aids in the learning of basic motor skills in the brain. It is associated with the nodulus of the vermis; together, these two structures compose the vestibular part of the cerebellum. At its base, the flocculus receives input from the inner ear's vestibular system and regulates balance. Many floccular projections connect to the motor nuclei involved in control of eye movement.
  • 6.2K
  • 02 Nov 2022
Topic Review
Traditional Chinese Timekeeping
The traditional Chinese time systems refers to the time standards for divisions of the day used in China until the introduction of the Shixian calendar in 1628 at the beginning of the Qing dynasty.
  • 6.2K
  • 30 Oct 2022
Topic Review
Irreligion
Irreligion or nonreligion is the absence or rejection of religion, or indifference to it. Irreligion takes many forms, ranging from the casual and unaware to full-fledged philosophies such as atheism and agnosticism, secular humanism and antitheism. Social scientists tend to define irreligion as a purely naturalist worldview that excludes a belief in anything supernatural. The broadest and loosest definition, serving as an upper limit, is the lack of religious identification, though many non-identifiers express metaphysical and even religious beliefs. The narrowest and strictest is subscribing to positive atheism. According to the Pew Research Center's 2012 global study of 230 countries and territories, 16% of the world's population does not identify with any religion. The population of the religiously unaffiliated, sometimes referred to as "nones", grew significantly in recent years. Measurement of irreligiosity requires great cultural sensitivity, especially outside the West, where the concepts of "religion" or "the secular" are not always rooted in local culture.
  • 6.2K
  • 17 Nov 2022
Topic Review
Porridge
Porridge (historically also spelled porage, porrige, or parritch) is a food commonly eaten as a breakfast cereal dish, made by boiling ground, crushed or chopped starchy plants—typically grain—in water or milk. It is often cooked or served with added flavorings such as sugar, honey, (dried) fruit or syrup to make a sweet cereal, or it can be mixed with spices or vegetables to make a savoury dish. It is usually served hot in a bowl, depending on its consistency. Oat porridge, or oatmeal, is one of the most common types of porridge. Gruel is a thinner version of porridge.
  • 6.1K
  • 02 Nov 2022
Topic Review
Social Media and the Arab Spring
The role of social media in the Arab Spring, a revolutionary wave of demonstrations and protests in the Middle East and North Africa between 2010 and 2012, remains a highly debated subject. Uprisings occurred both in states with very high levels of Internet usage (such as Bahrain, with 88% of its population online in 2011) and in states with some of the lowest levels of Internet penetration (such as Yemen and Libya).
  • 6.1K
  • 09 Oct 2022
Topic Review
Iranian Subsidy Reform Plan
The economy of Iran includes a lot of subsidies. The Iranian targeted subsidy plan (Persian: طرح هدفمندسازی یارانه‌ها‎), also known as the subsidy reform plan, was passed by the Iranian Parliament in 2010. The government described the subsidy plan as the "biggest surgery" to the nation's economy in half a century and "one of the most important undertakings in Iran's recent economic history". The goal of the subsidy reform plan is to replace subsidies on food and energy (80% of total) with targeted social assistance, in accordance with a Five Year Economic Development Plan and a move towards free market prices in a 5-year period. The subsidy reform plan is the most important part of a broader Iranian economic reform plan. According to the government, approximately $100 billion per year is spent on subsidizing energy prices ($45 billion for the prices of fuel alone) and many consumable goods including bread, sugar, rice, cooking oil and medicine. However, some experts believe direct subsidies are about $30 billion, depending on oil prices. The subsidy system has been inherited from the Iran–Iraq War era but was never abolished. Iran is one of the largest gasoline consumers in the world, ranking second behind the United States in consumption per car. The government subsidy reform has been years in the making, for reasons which are unclear. Iran's Supreme Leader has backed the government’s subsidy reform plan.
  • 6.1K
  • 13 Oct 2022
Topic Review
Railway and Tourism
From the second half of the 20th century, numerous railways, especially in industrial and mining areas, were abandoned for economic reasons. The activism of the “railfans”, who are fond of trains, has made it possible to set up voluntary associations that have been the lifeblood of the beginning of projects for the recovery of the historic railway heritage and the promotion of it in a touristic sense. The railway tourism process always originates from a project for the restoration of railway heritage, possibly maintaining authenticity. The voluntary associations, along with their “railfans”, are the main stakeholder, not only preserving the rail heritage but also developing railway tourism activities. The touristic railway could regenerate the local community, with positive benefits on the local economy. Many tourists could be attracted by railway tourism destinations in that they wish to live memorable experiences related to the nostalgia of the past. 
  • 6.1K
  • 25 Jan 2022
Topic Review
Love Live
Love Live! School Idol Project is a Japanese multimedia project co-developed by ASCII Media Works' Dengeki G's Magazine, music label Lantis, and animation studio Sunrise. The project revolves around a group of nine schoolgirl friends who become idols in order to save their school from shutting down. It launched in the August 2010 issue of Dengeki G's Magazine, and went on to produce music CDs, anime music videos, two manga adaptations, and video games. A 13-episode anime television series produced by Sunrise, directed by Takahiko Kyōgoku, and written by Jukki Hanada aired in Japan between January and March 2013, with a second season airing between April and June 2014. Both anime series and film are licensed in North America, the United Kingdom, Australia and New Zealand by NIS America, MVM Entertainment and Madman Entertainment, respectively. An animated film titled Love Live! The School Idol Movie was distributed by Shochiku and released in June 2015. A follow-up project focusing on a new set of idols, titled Love Live! Sunshine!!, launched in 2015.
  • 6.1K
  • 20 Oct 2022
Topic Review
IBM Cloud Computing
IBM cloud computing is a set of cloud computing services for business offered by the information technology company IBM. IBM Cloud includes infrastructure as a service (IaaS), software as a service (SaaS) and platform as a service (PaaS) offered through public, private and hybrid cloud delivery models, in addition to the components that make up those clouds.
  • 6.1K
  • 20 Oct 2022
Topic Review
Learning Styles
Learning styles refer to a range of competing and debunked theories that aim to account for differences in individuals' learning. Many theories share the proposition that humans can be classified according to their 'style' of learning, but differ in how the proposed styles should be defined, categorized and assessed.:8 A common concept is that individuals differ in how they learn.:266 The idea of individualized learning styles became popular in the 1970s, and has greatly influenced education despite the criticism that the idea has received from some researchers.:107–108 Proponents recommend that teachers have to run a needs analysis to assess the learning styles of their students and adapt their classroom methods to best fit each student's learning style. Although there is ample evidence that individuals express personal preferences for how they prefer to receive information,:108 few studies have found any validity in using learning styles in education.:267 Critics say there is no consistent evidence that identifying an individual student's learning style and teaching for specific learning styles produces better student outcomes.:33 Since 2012, Learning Styles have often been referred to as a "neuromyth" in education. There is evidence of empirical and pedagogical problems related to forcing learning tasks to "correspond to differences in a one-to-one fashion". Studies contradict the widespread "meshing hypothesis" that a student will learn best if taught in a method deemed appropriate for the student's learning style. However, a 2020 systematic review suggested that a majority (89%) of educators around the world continue to believe that the meshing hypothesis is correct. Studies further show that teachers cannot assess the learning style of their students accurately.
  • 6.1K
  • 02 Nov 2022
Topic Review
Salvia divinorum
Salvia divinorum Epling and Játiva is a psychoactive Mexican mint used for centuries by Mazatec Indian shamans or curanderos of north-eastern Oaxaca, Mexico, for divinatory and religious purposes and physical healing.
  • 6.1K
  • 18 Mar 2021
Topic Review
Independent Video Game Development
Independent video game development, or indie game development, is the video game development process of creating indie games; these are video games, commonly created by individual or small teams of video game developers and usually without significant financial support of a video game publisher or other outside source. These games may take years to be built from the ground up or can be completed in a matter of days or even hours depending on complexity, participants, and design goal. Driven by digital distribution, the concept of independent video game development has spawned an "indie" movement. The increase in popularity of independent games has allowed increased distribution on popular gaming platforms such as the PlayStation Network, Nintendo eShop, Xbox Live and Steam.
  • 6.1K
  • 21 Nov 2022
Topic Review
Paradigm Shift
A paradigm shift refers to a fundamental change in the underlying assumptions, beliefs, or frameworks that guide a particular field of knowledge or practice. It represents a transformative departure from established models of thought, leading to a reevaluation of existing principles and often opening new avenues for understanding and problem-solving within that domain.
  • 6.1K
  • 25 Jan 2024
Topic Review
Independent Legal Reasoning in Islamic Law
Ijtihad (Arabic: اجتهاد ijtihād, [ʔidʒ.tihaːd]; lit. physical or mental effort) is an Islamic legal term referring to independent reasoning by an expert in Islamic law, or the thorough exertion of a jurist's mental faculty in finding a solution to a legal question. It is contrasted with taqlid (imitation, conformity to legal precedent). According to classical Sunni theory, ijtihad requires expertise in the Arabic language, theology, revealed texts, and principles of jurisprudence (usul al-fiqh), and is not employed where authentic and authoritative texts (Qur'an and Hadith) are considered unambiguous with regard to the question, or where there is an existing scholarly consensus (ijma). Ijtihad is considered to be a religious duty for those qualified to perform it. An Islamic scholar who is qualified to perform ijtihad is called a mujtahid. Throughout the first five Islamic centuries, the practice of ijtihad continued both theoretically and practically amongst Sunni Muslims. The controversy surrounding ijtihad and the existence of mujtahids started, in its primitive form, around the beginning of the sixth/twelfth century. By the 14th century, development of Sunni jurisprudence prompted leading Sunni jurists to state that the main legal questions had been addressed and the scope of ijtihad was gradually restricted. In the modern era, this gave rise to a perception among Western scholars and lay Muslim public that the so-called "gate of ijtihad" was closed at the start of the classical era. While recent scholarship established that the practice of Ijtihad had never ceased in Islamic history, the extent and mechanisms of legal change in the post-formative period remain a subject of debate. Differences amongst the jurists prevented Muslims from reaching any consensus(Ijma) on the issues of continuity of Ijtihad and existence of Mujtahids. Thus, Ijtihad remained a key aspect of Islamic jurisprudence throughout the centuries. Ijtihad was practiced throughout the Early modern period and claims for ijtihad and its superiority over taqlid were voiced unremittingly. Starting from the 18th century, Islamic reformers began calling for abandonment of taqlid and emphasis on ijtihad, which they saw as a return to Islamic origins. Public debates in the Muslim world surrounding ijtihad continue to the present day. The advocacy of ijtihad has been particularly associated with Islamic modernist and Salafiyya movements. Among contemporary Muslims in the West there have emerged new visions of ijtihad which emphasize substantive moral values over traditional juridical methodology. Shia jurists did not use the term ijtihad until the 12th century. With the exception of Zaydi jurisprudence, the early Imami Shia were unanimous in censuring Ijtihad in the field of law (Ahkam). After the Shiite embracal of various doctrines of Mu'tazila and classical Sunnite Fiqh (jurisprudence), this led to a change. After the victory of the Usulis who based law on principles (usul) over the Akhbaris ("traditionalists") who emphasized on reports or traditions (khabar) by the 19th century, Ijtihad would become a mainstream Shia practice.
  • 6.1K
  • 22 Nov 2022
Topic Review
Electrocommunication
Electrocommunication is the communication method used by weakly-electric fish. Weakly-electric fish are a group of animals that utilize a communicating channel that is "invisible" to most other animals: electric signaling. Electric fish communicate by generating an electric field that a second individual receives with its electroreceptors. The fish interprets the message using the signal's frequencies, waveforms, delay, etc. The best studied species are two freshwater lineages- the African Mormyridae and the South American Gymnotiformes. While weakly-electric fish are the only group that have been identified to carry out both generation and reception of electric fields, other species either generate signals or receive them, but not both. Animals that either generate or receive electric fields are found only in wet or aquatic environments due to water's relatively low electrical resistance, compared to other substances (e.g. air). So far, communication between electric fish has been identified mainly to serve the purpose of conveying information such as: species courtship and biological sex motivational status (e.g. attack warning, submission, etc.) environmental conditions
  • 6.1K
  • 31 Oct 2022
Topic Review
Pre–Indo-European Languages
Pre-Indo-European languages are any of several ancient languages, not necessarily related to one another, that existed in prehistoric Europe and South Asia before the arrival of speakers of Indo-European languages. The oldest Indo-European language texts date from the 19th century BC in Kültepe in modern-day Turkey, and while estimates vary widely, spoken Indo-European languages are believed to have developed at the latest by the third millennium BC (see Proto-Indo-European Urheimat hypotheses). Thus the Pre-Indo-European languages must have developed earlier than, or in some cases alongside, the Indo-European languages that ultimately displaced them. A handful of these languages still survive; in Europe, Basque retains a localized strength with fewer than a million native speakers, while the Dravidian languages of South Asia remain very widespread there, with over 200 million native speakers. Some of the pre-Indo-European languages are attested only as linguistic substrates in Indo-European languages. A few others (such as Etruscan, Minoan, Iberian, etc.) are also attested from inscriptions.
  • 6.1K
  • 02 Nov 2022
Topic Review
Evolution of Dinosaurs
Dinosaurs evolved within a single lineage of archosaurs 243-233 Ma (million years ago) from the Anisian to the Carnian ages, the latter part of the middle Triassic. Dinosauria is a well-supported clade, present in 98% of bootstraps. It is diagnosed by many features including loss of the postfrontal on the skull and an elongate deltopectoral crest on the humerus. In March 2017, scientists reported a new way of classifying the dinosaur family tree, based on newer and more evidence than available earlier. According to the new classification, the original dinosaurs, arising 200 million years ago, were small, two-footed omnivorous animals with large grasping hands. Descendants (for the non-avian dinosaurs) lasted until 66 million years ago.
  • 6.1K
  • 14 Oct 2022
Topic Review
Effects of Exercise on the Autonomic Nervous System
The autonomic nervous system (ANS) has an important impact on health in general. In response to environmental demands, homeostatic processes are often compromised, therefore determining an increase in the sympathetic nervous system (SNS)’s functions and a decrease in the parasympathetic nervous system (PNS)’s functions.
  • 6.1K
  • 21 Feb 2022
Topic Review
Polylactic Acid
As a degradable and environmentally friendly polymer, polylactic acid, also known as polylactide, is favored by researchers and has been used as a commercial material in various studies. Lactic acid, as a synthetic raw material of polylactic acid, can only be obtained by sugar fermentation. Good biocompatibility and biodegradability have led it to be approved by the U.S. Food and Drug Administration (FDA) as a biomedical material. Polylactic acid has good physical properties, and its modification can optimize its properties to a certain extent. Polylactic acid blocks and blends play significant roles in drug delivery, implants, and tissue engineering to great effect.  This entry introduces synthesis and biological application of polylactic acid.
  • 6.1K
  • 17 Nov 2020
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