Your browser does not fully support modern features. Please upgrade for a smoother experience.
Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort by:
Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)
Filter:
All Topic Review Biography Peer Reviewed Entry Video Entry
Topic Review
Division of Labour
The division of labour is the separation of tasks in any economic system or organisation so that participants may specialise (specialisation). Individuals, organizations, and nations are endowed with or acquire specialised capabilities and either form combinations or trade to take advantage of the capabilities of others in addition to their own. Specialised capabilities may include equipment or natural resources as well as skills and training and combinations of such assets acting together are often important. For example, an individual may specialise by acquiring tools and the skills to use them effectively just as an organization may specialize by acquiring specialised equipment and hiring or training skilled operators. The division of labour is the motive for trade and the source of economic interdependence. Historically, an increasing division of labour is associated with the growth of total output and trade, the rise of capitalism, and the increasing complexity of industrialised processes. The concept and implementation of division of labour has been observed in ancient Sumerian (Mesopotamian) culture, where assignment of jobs in some cities coincided with an increase in trade and economic interdependence. Division of labour generally also increases both producer and individual worker productivity. After the Neolithic Revolution, pastoralism and agriculture led to more reliable and abundant food supplies, which increased the population and led to specialisation of labour, including new classes of artisans, warriors, and the development of elites. This specialistion was furthered by the process of industrialisation, and Industrial Revolution-era factories. Accordingly, many classical economists as well as some mechanical engineers such as Charles Babbage were proponents of division of labour. Also, having workers perform single or limited tasks eliminated the long training period required to train craftsmen, who were replaced with lesser paid but more productive unskilled workers.
  • 6.0K
  • 17 Oct 2022
Topic Review
Autonomous Spaceport Drone Ship
An autonomous spaceport drone ship (ASDS) is an ocean-going vessel derived from a deck barge, outfitted with station-keeping engines and a large landing platform. Construction of such ships was commissioned by aerospace company SpaceX to allow for recovery of rocket first-stages at sea for high-velocity missions which do not carry enough fuel to return to the launch site after lofting spacecraft onto an orbital trajectory. SpaceX has two operational drone ships and has a third under construction as of early 2018. Just Read the Instructions operates in the Pacific for launches from Vandenberg Air Force Base ; Of Course I Still Love You operates in the Atlantic for launches from Cape Canaveral. A Shortfall of Gravitas is under construction. (As of August 2018), 23 Falcon 9 flights have attempted to land on a drone ship, with 17 of them succeeding. The ASDS ships are a key component of the SpaceX reusable launch system development program which aims to significantly lower the price of space launch services through "full and rapid reusability." Any flights going to geostationary orbit or exceeding escape velocity will require landing at sea, encompassing about half of SpaceX missions.
  • 6.0K
  • 27 Oct 2022
Topic Review
Organ
In biology, an organ is a collection of tissues joined in a structural unit to serve a common function. In the hierarchy of life, an organ lies between tissue and an organ system. Tissues are formed from same type cells to act together in a function. Tissues of different types combine to form an organ which has a specific function. The intestinal wall for example is formed by epithelial tissue and smooth muscle tissue. Two or more organs working together in the execution of a specific body function form an organ system, also called a biological system or body system. An organ's tissues can be broadly categorized as parenchyma, the functional tissue, and stroma, the structural tissue with supportive, connective, or ancillary functions. For example, the gland's tissue that makes the hormones is the parenchyma, whereas the stroma includes the nerves that innervate the parenchyma, the blood vessels that oxygenate and nourish it and carry away its metabolic wastes, and the connective tissues that provide a suitable place for it to be situated and anchored. The main tissues that make up an organ tend to have common embryologic origins, such as arising from the same germ layer. Organs exist in most multicellular organisms. In single-celled organisms such as bacteria, the functional analogue of an organ is known as an organelle. In plants, there are three main organs. In the study of anatomy, viscera (singular viscus) refers to the internal organs of the abdominal, thoracic, and pelvic cavities. The abdominal organs may be classified as solid organs, or hollow organs. The solid organs are the liver, pancreas, spleen, kidneys, and adrenal glands. The hollow organs of the abdomen are the stomach, intestines, gallbladder, bladder, and rectum. In the thoracic cavity the heart is a hollow, muscular organ. The number of organs in any organism depends on the definition used. By one widely adopted definition, 79 organs have been identified in the human body.
  • 6.0K
  • 14 Oct 2022
Topic Review
Diarchy
A diarchy (from Greek δι-, di-, "double", and -αρχία, -arkhía, "ruled")[note 1] or duumvirate (from Latin duumvirātus, "the office of the two men")[note 2] is a form of government characterized by corule, with two people ruling a polity together either lawfully or de facto, by collusion and force. The leaders of such a system are usually known as corulers. Historically, diarchy particularly referred to the system of shared rule in British India established by the Government of India Acts 1919 and 1935, which devolved some powers to local councils, which had included native Indian representation under the Indian Councils Act 1892. 'Duumvirate' principally referred to the offices of the various duumviri established by the Roman Republic. Both, along with less common synonyms such as biarchy and tandemocracy,[note 3] are now used more generally to refer to any system of joint rule or office. A monarchy temporarily controlled by two or more people is, however, usually distinguished as a coregency. Corule is one of the oldest forms of government. Historical examples include the Pandyan dynasty of Tamilakam, Sparta's joint kingdom, the Roman Republic's consuls, Carthage's Judges, and several ancient Polynesian societies. Systems of inheritance that often led to corule in Germanic and Dacian monarchies may be included as well, as may the dual occupants of the ranks of the Inca Empire. Modern examples of diarchies are Andorra, whose princes are the President of France and the Bishop of Urgell in Catalonia; and San Marino, whose republic is led by two Captains Regent.
  • 6.0K
  • 14 Nov 2022
Topic Review
Michael Addition of Carbonyl Compounds to α,β-Unsaturated Nitroalkenes
The proline-catalyzed asymmetric Michael addition reaction of acetaldehyde with α,β-unsaturated nitroalkenes as synthetically useful routes to β-substituted derivatives of γ-Aminobutyric acid (GABA).
  • 6.0K
  • 01 Jul 2022
Topic Review
Rock Art
The term ‘rock art’ defines non-utilitarian humanly made markings on natural rock surfaces, caused either by an additive (pictograms, made by the application of material) or a reductive process (petroglyphs, made by the removal of rock material). The former include rock paintings, pigment drawings, stencils, and beeswax figures; the latter term covers engravings, percussion petroglyphs, and finger flutings. Rock art occurs in nearly all countries. Its uneven distribution is attributable to differences in cultural conventions as well as a taphonomic attribute, i.e. a result of preservation bias. Prehistoric rock art represents by far the largest body of evidence we possess of humanity’s cultural, cognitive, and artistic beginnings. Through its relative permanence, it has profoundly influenced the beliefs and cultural conventions of subsequent societies up to the present. It is, therefore, an integral part of humanity's collective memory and the most significant surviving witness of our cultural evolution. 
  • 6.0K
  • 07 Apr 2021
Topic Review
Tattvartha Sutra
Tattvartha Sutra (also known as Tattvarth-adhigama-sutra or Moksha-shastra) is an ancient Jain text written by Acharya Umaswami (Umaswami), sometime between the 2nd- and 5th-century AD. It is one of the Jain scriptures written in the Sanskrit language. The term Tattvartha is composed of the Sanskrit words tattva which means "reality, truth" and artha which means "nature, meaning", together meaning "nature of reality". The Tattvartha Sutra is regarded as one of the earliest, most authoritative texts in Jainism. It is accepted as authoritative in both its major sub-traditions – Digambara and Śvētāmbara – as well as the minor sub-traditions. It is a philosophical text, and its importance in Jainism is comparable with that of the Brahma Sutras and Yoga Sutras of Patanjali in Hinduism. In an aphoristic sutra style of ancient Indian texts, it presents the complete Jainism philosophy in 350 sutras over 10 chapters. The text has attracted numerous commentaries, translations and interpretations since the 5th-century. One of its sutras, Parasparopagraho Jivanam is the motto of Jainism. Its meaning is interpreted as "(The function) of souls is to help one another", or "Souls render service to one another".
  • 6.0K
  • 03 Nov 2022
Topic Review
Trickster
In mythology, and in the study of folklore and religion, a trickster is a character in a story (god, goddess, spirit, human, or anthropomorphisation), which exhibits a great degree of intellect or secret knowledge, and uses it to play tricks or otherwise disobey normal rules and conventional behaviour.
  • 6.0K
  • 03 Nov 2022
Topic Review
Low Intensity Conflict
A low-intensity conflict (LIC) is a military conflict, usually localised, between two or more state or non-state groups which is below the intensity of conventional war. It involves the state's use of military forces applied selectively and with restraint to enforce compliance with its policies or objectives. The term can be used to describe conflicts where at least one or both of the opposing parties operate along such lines.
  • 6.0K
  • 27 Sep 2022
Topic Review
Floating Wind Turbines
Globally, the wind resource in deep water (depths > 60 m) is very abundant. Due to the abundance of potential at these depths, the wind turbines will need the design of a floating platform because the wind turbines that are currently in operation are mostly fixed at the bottom and are dependent upon conventional concrete with a gravity base that is not feasible at these depths. A balance among the two varying principles (i.e., the requirement for a stable foundation for the wind turbine’s control and operation and the nature of the substructure being innate, to respond to environmental forces) is required for the design of the floating platform for wind energy. The absence of rigid foundations results in an additional six degrees of freedom (DOFs) for the platform of floating turbines; three translational (surge X, sway Y, and heave Z) and three rotational (roll RotX, pitch RotY, and yaw RotZ). For the platforms of onshore wind turbines and bottom-mounted offshore wind turbines, the effect of soil-structure interaction (SSI) can be modeled with six degrees of freedom; three translational (horizontal forces in X and Y and vertical force in Z) and three rotational (rocking moments in X and Y and a torsional moment in Z) respectively.
  • 6.0K
  • 11 Oct 2021
Topic Review
Microgrid and Its Architecture
The world today is plagued with problems of increased transmission and distribution (T&D) losses leading to poor reliability due to power outages and an increase in the expenditure on electrical infrastructure. To address these concerns, technology has evolved to enable the integration of renewable energy sources (RESs) like solar, wind, diesel and biomass energy into small scale self-governing power system zones which are known as micro-grids (MGs). A de-centralised approach for modern power grid systems has led to an increased focus on distributed energy resources and demand response. MGs act as complete power system units albeit on a small scale. However, this does not prevent them from large operational sophistication allowing their independent functioning in both grid-connected and stand-alone modes. MGs provide greater reliability as compared to the entire system owing to the large amount of information secured from the bulk system. They comprise numerous sources like solar, wind, diesel along with storage devices and converters. Several modeling schemes have been devised to reduce the handling burden of large scale systems. 
  • 6.0K
  • 18 Jan 2022
Topic Review
Communalism
Communalism usually refers to a system that integrates communal ownership and federations of highly localized independent communities. A prominent libertarian socialist, Murray Bookchin, defines the Communalism political philosophy that he developed as "a theory of government or a system of government in which independent communes participate in a federation", as well as "the principles and practice of communal ownership". The term 'government' in this case does not imply an acceptance of a State or top-down hierarchy. This usage of communalism appears to have emerged during the late 20th century to distinguish commune-based systems from other political movements and/or governments espousing (if not actually practicing) similar ideas. In particular, earlier communities and movements advocating such practices were often described as "anarchist", "socialist" and/or "communist". Many historical communities practicing utopian socialism or anarcho-communism did implement internal rules of communalist property ownership in the context of federated communalism. It is at least theoretically possible for a federation of communes to include communes which do not practice communalist rules of property, which is to say, that the overall national government may be a federation of communes, but that private property rather than communalist property is the order within each such commune. Karl Marx, often viewed as the founder of modern communism, criticized older forms, including primitive communism and/or utopian socialism, as poorly conceived and/or prone to disintegration in practice. Communalism in the form described above is distinct from the predominant usage in South Asian forms of English: allegiance to a particular ethnic and/or religious group rather than to a broader society. As such, this usage is synonymous with sectarianism and associated with communal violence.
  • 6.0K
  • 16 Nov 2022
Topic Review
Properties and Synthesis of Photocatalysts
The photocatalysts must be characterized by the ability to absorb radiation from a wide spectral range of light, the appropriate position of the semiconductor energy bands in relation to the redox reaction potentials, and the long diffusion path of charge carriers, besides the thermodynamic, electrochemical, and photoelectrochemical stabilities.
  • 6.0K
  • 30 Dec 2022
Topic Review
Plant Nutrition for Human Health
Is there any relationship between plant nutrition and human health? The overall response to this question is very positive, and a strong relationship between the nutrition of plants and humans has been reported. The nutritional status of edible plants consumed by humans can have a negative or positive impact on human health.
  • 6.0K
  • 14 Jul 2022
Topic Review
Sallekhana
Sallekhana (IAST: sallekhanā), also known as Samlehna, Santhara, Samadhi-marana or Sanyasana-marana; is a supplementary vow to the ethical code of conduct of Jainism. It is the religious practice of voluntarily fasting to death by gradually reducing the intake of food and liquids. It is viewed in Jainism as the thinning of human passions and the body, and another means of destroying rebirth-influencing karma by withdrawing all physical and mental activities. It is not considered as a suicide by Jain scholars because it is not an act of passion, nor does it deploy poisons or weapons. After the sallekhana vow, the ritual preparation and practice can extend into years. Sallekhana is a vow available to both for Jain ascetics and householders. Historic evidence such as nishidhi engravings suggest sallekhana was observed by both men and women, including queens, in Jain history. However, in the modern era, death through sallekhana has been a relatively uncommon event. There is debate about the practice from a right to life and a freedom of religion viewpoint. In 2015, the Rajasthan High Court banned the practice, considering it suicide. Later that year, the Supreme Court of India stayed the decision of the Rajasthan High Court and lifted the ban on Sallekhana.
  • 6.0K
  • 10 Nov 2022
Topic Review
Different Types of Literature Review
Literature reviews are crucial for demonstrating progress and a comprehensive understanding of a subject. However, an unorganized growth in literature can lead to complicated and competing arguments, hindering progress. This research delves into different types of literature reviews and the common mistakes researchers make when conducting them. Learning how to efficiently conduct a literature review is essential for success in academia and professional careers.
  • 6.0K
  • 09 May 2023
Topic Review
2015–16 Chinese Stock Market Turbulence
The Chinese stock market turbulence began with the popping of the stock market bubble on 12 June 2015 and ended in early February 2016. A third of the value of A-shares on the Shanghai Stock Exchange was lost within one month of the event. Major aftershocks occurred around 27 July and 24 August's "Black Monday". By 8–9 July 2015, the Shanghai stock market had fallen 30 percent over three weeks as 1,400 companies, or more than half listed, filed for a trading halt in an attempt to prevent further losses. Values of Chinese stock markets continued to drop despite efforts by the government to reduce the fall. After three stable weeks the Shanghai index fell again on 24 August by 8.48 percent, marking the largest fall since 2007. At the October 2015 International Monetary Fund (IMF) annual meeting of "finance ministers and central bankers from the Washington-based lender’s 188 member-countries" held in Peru, China's slump dominated discussions with participants asking if "China’s economic downturn [would] trigger a new financial crisis". By the end of December 2015 China's stock market had recovered from the shocks and had outperformed S&P for 2015, though still well below the 12 June highs. By the end of 2015 the Shanghai Composite Index was up 12.6 percent. In January 2016 the Chinese stock market experienced a steep sell-off and trading was halted on 4 and 7 January 2016 after the market fell 7%, the latter within 30 minutes of open. The market meltdown set off a global rout in early 2016. According to 19 January 2016 articles in the Xinhua News Agency, the official press agency of the China , China reported a 6.9 percent GDP growth rate for 2015 and an "economic volume of over ten trillion U.S. dollars". Forbes journalist argues that the "stock market crash does not indicate a blowout of the Chinese physical economy." China is shifting from a focus on manufacturing to service industries and while it has slowed down, it is still growing by 5%. After this last turbulence, as of January 2017 the Shanghai Composite Index has been stable around 3,000 points, 50% less than before the bubble popped.
  • 6.0K
  • 28 Nov 2022
Topic Review
Polyoxymethylene
Polyoxymethylene (POM) is a material able to provide tooth-colored esthetics and that is suitable for fabrication of frameworks for removable dental prostheses. POM can be characterized as both polyethers (-C-O-) as well as polyacetals (-O-C-O-).
  • 6.0K
  • 29 Apr 2021
Topic Review
Location-Based Social Networks
There are several definitions for “geosocial network” or “location-based social network”: the first formal definition was given by Quercia et al. in 2010, who defined it as “a type of social networking in which geographic services and capabilities such as geocoding and geotagging are used to enable additional social dynamics”. One year later, Zheng refined this definition by stating that “a location-based social network (LBSN) does not only mean adding a location to an existing social network so that people in the social structure can share location embedded information but also consists of the new social structure made up of individuals connected by the interdependency derived from their locations in the physical world as well as their location-tagged media content, such as photos, video, and texts”. In 2013, Roick and Heuser defined LBSNs simply as “social network sites that include location information into shared contents”. Finally, one most recent definition is given by Armenatzoglou and Papadias and is the following: “geosocial network (GeoSN) is an online social network augmented by geographical information”.
  • 6.0K
  • 17 Jan 2022
Topic Review
Agriculture Robotics
Agricultural robotics aims to overcome the challenges imposed by population growth, accelerated urbanization, high competitiveness of high-quality products, environmental preservation and a lack of qualified labor. The main existing applications of agricultural robotic systems are for the execution of land preparation before planting, sowing, planting, plant treatment, harvesting, yield estimation and phenotyping.
  • 6.0K
  • 05 May 2021
  • Page
  • of
  • 2727
Academic Video Service