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Topic Review
Perceptual Organization
Gestalt theory has provided perceptual science with a conceptual framework relating to brain mechanisms that determine the way we see the visual world. This is referred to as "Perceptual Organization" and has inspired researchers in Psychology, Neuroscience and Computational Design ever since. The major Gestalt principles, such as the principle of Prägnanz, and more importantly the Gestalt laws of perceptual organization, have been critically important to our understanding of visual information processing, how the brain detects order in what we see, and derives likely perceptual representations from statistically significant structural regularities. The perceptual integration of contrast information across co-linear space for the organization of objects in the 2D image plane into figure and ground convey the most elementary basis to our understanding of the visual world. Gestalt theory continues to generate powerful concepts and insights for perceptual science even today, where it is to be placed in the context of image-base decision making by human minds and machines.
  • 12.0K
  • 22 Mar 2021
Topic Review
Fiber Crops
Fibers are everywhere around us and they are essential materials supporting our daily lives. Most fibers that we use in our daily activities are derived from fiber crops. In this entry, we introduce how fibers are classified, describe the main fiber crops in the world, and summarize their distributions and main usages by humans.
  • 12.0K
  • 01 Jul 2020
Topic Review
North–South Divide (England)
In England, the term North–South divide refers to the cultural, economic, and social differences between: The status of the Midlands is often disputed, however counties in the higher midlands, such as West Midlands County (Walsall Metropolitan Borough and Wolverhampton are seen as north too due to their proximity to Staffordshire and Shropshire), Shropshire, Derbyshire, Nottinghamshire, Lincolnshire, Leicestershire, and Staffordshire, are culturally very Northern. A grouping of Central England based on UK EU parliamentary constituency boundaries combines the Midlands and East Anglia. In political terms, the South, and particularly the South-East (outside Greater London) and East Anglia, is largely centre-right, and supportive of the Conservative Party, while Northern England (particularly the towns and cities) is generally more supportive of the Labour Party. An article in The Economist (15–21 September 2012) argued that the gap between the north and south in life expectancy, political inclinations and economics trends was growing to the extent that they were almost separate countries.
  • 12.0K
  • 11 Oct 2022
Topic Review
Starter Cultures in Foods
Starter cultures can be defined as preparations with a large number of cells that include a single type or a mixture of two or more microorganisms that are added to foods in order to take advantage of the compounds or products derived from their metabolism or enzymatic activity.
  • 11.9K
  • 19 Apr 2021
Topic Review
Antenna Aperture
In electromagnetics and antenna theory, antenna aperture, effective area, or receiving cross section, is a measure of how effective an antenna is at receiving the power of electromagnetic radiation (such as radio waves). The aperture is defined as the area, oriented perpendicular to the direction of an incoming electromagnetic wave, which would intercept the same amount of power from that wave as is produced by the antenna receiving it. Assume a plane wave in a particular direction has an irradiance or power flux density [math]\displaystyle{ S }[/math]; this is the amount of power passing through a unit area of one square meter. Then if an antenna delivers [math]\displaystyle{ P_o }[/math] watts to the load connected to its output terminals (e.g. the receiver) when irradiated by a uniform field of power density [math]\displaystyle{ S }[/math] watts per square meter, the antenna's aperture for the direction of that plane wave is [math]\displaystyle{ A_e }[/math] in square meters, given by: So the power received by an antenna (in watts) is equal to the power density of the electromagnetic energy (in watts per square meter), multiplied by its aperture (in square meters). Radio waves from a direction where the antenna's aperture is larger thus collect a greater amount of that wave's power; this is more often referred to as antenna gain. To actually obtain that available power [math]\displaystyle{ P_o }[/math], the incoming radiation must be in the state of polarization specified for that antenna, and the load (receiver) must be impedance matched to the antenna's feedpoint impedance. The meaning of aperture is thus based on a receiving antenna, however any receiving antenna can also be used for transmission. Due to reciprocity, an antenna's gain in receiving and transmitting are identical, so the power transmitted by an antenna in different directions (the radiation pattern) is always proportional to the effective area [math]\displaystyle{ A_e }[/math] in each direction; that proportionality factor is derived below. When no direction is specified, [math]\displaystyle{ A_e }[/math] (or "antenna gain") is understood to refer to its maximum value, that is, in the intended direction(s) that the antenna is designed to receive from and/or transmit toward.
  • 11.9K
  • 27 Oct 2022
Topic Review
Thermal Stability of Structural Materials
Thermal stability determines the material ability of retaining its properties at required temperatures over extended service time. In addition to temperature and time, thermal stability is affected by load conditions and environmental conditions.
  • 11.9K
  • 20 Aug 2020
Topic Review
Tyrannosaurus
Tyrannosaurus is a genus of large theropod dinosaur. The species Tyrannosaurus rex (rex meaning "king" in Latin), often called T. rex or colloquially T-Rex, is one of the best represented theropods. Tyrannosaurus lived throughout what is now western North America, on what was then an island continent known as Laramidia. Tyrannosaurus had a much wider range than other tyrannosaurids. Fossils are found in a variety of rock formations dating to the Maastrichtian age of the Upper Cretaceous period, 68 to 66 million years ago. It was the last known member of the tyrannosaurids and among the last non-avian dinosaurs to exist before the Cretaceous–Paleogene extinction event. Like other tyrannosaurids, Tyrannosaurus was a bipedal carnivore with a massive skull balanced by a long, heavy tail. Relative to its large and powerful hind limbs, the forelimbs of Tyrannosaurus were short but unusually powerful for their size, and they had two clawed digits. The most complete specimen measures up to 12.3–12.4 m (40.4–40.7 ft) in length; however, according to most modern estimates, T. rex could grow to lengths of over 12.4 m (40.7 ft), up to 3.66–3.96 m (12–13 ft) tall at the hips, and 8.87 metric tons (9.78 short tons) in body mass. Although other theropods rivaled or exceeded Tyrannosaurus rex in size, it is still among the largest known land predators and is estimated to have exerted the strongest bite force among all terrestrial animals. By far the largest carnivore in its environment, Tyrannosaurus rex was most likely an apex predator, preying upon hadrosaurs, juvenile armored herbivores like ceratopsians and ankylosaurs, and possibly sauropods. Some experts have suggested the dinosaur was primarily a scavenger. The question of whether Tyrannosaurus was an apex predator or a pure scavenger was among the longest debates in paleontology. Most paleontologists today accept that Tyrannosaurus was both an active predator and a scavenger. Specimens of Tyrannosaurus rex include some that are nearly complete skeletons. Soft tissue and proteins have been reported in at least one of these specimens. The abundance of fossil material has allowed significant research into many aspects of its biology, including its life history and biomechanics. The feeding habits, physiology, and potential speed of Tyrannosaurus rex are a few subjects of debate. Its taxonomy is also controversial, as some scientists consider Tarbosaurus bataar from Asia to be a second Tyrannosaurus species, while others maintain Tarbosaurus is a separate genus. Several other genera of North American tyrannosaurids have also been synonymized with Tyrannosaurus. As the archetypal theropod, Tyrannosaurus has been one of the best-known dinosaurs since the early 20th century and has been featured in film, advertising, postal stamps, and many other media.
  • 11.9K
  • 06 Dec 2022
Topic Review
9M133 Kornet
The 9M133 Kornet (Russian: Корнет; "Cornet", NATO reporting name AT-14 Spriggan, export designation Kornet-E) is a modern Russian man-portable anti-tank guided missile (ATGM) intended for use against main battle tanks. It was first introduced into service with the Russian army in 1998. The Kornet is among the most capable Russian ATGMs. It is not intended to fully replace previous systems, due to its high cost. The Kornet comes in variants with thermobaric warheads for use against soft targets. It was further developed into the 9M133 Kornet-EM, which has increased range, fire-and-forget capability, and an improved warhead. The Kornet has been widely exported and is produced under license in several countries. It was first used in combat in 2003 and has since been used in many conflicts. The NATO reporting name AT-14 Spriggan is derived from the spriggan, a legendary creature from Cornish faery lore.
  • 11.9K
  • 08 Nov 2022
Topic Review
Effects of Petroleum on Soil
Petroleum is the most common global fossil fuel. It is a complex multi-component system mainly composed of various hydrocarbons such as alkanes, cycloalkanes, mono-, bi- and polyaromatic compounds, resins and asphaltenes. In spite of humanity’s need for petroleum, it negatively affects the environment due to its toxicity. The ecological problem is especially serious at petroleum mining sites or during petroleum transportation. Since it is not possible to replace petroleum with less toxic fuel, ways to reduce the toxic impact of petroleum hydrocarbons on the environment need to be developed.
  • 11.9K
  • 08 Jul 2022
Biography
Katharine Burr Blodgett
Katharine Burr Blodgett (January 10, 1898 – October 12, 1979) was an American physicist and chemist known for her work on surface chemistry, in particular her invention of "invisible" or nonreflective glass while working at General Electric. She was the first woman to be awarded a Ph.D. in physics from the University of Cambridge, in 1926.[1] Blodgett was born on January 10, 1898 in Schenec
  • 11.9K
  • 18 Nov 2022
Topic Review
Digital Twin: Origin to Future
Digital Twin (DT) refers to the virtual copy or model of any physical entity (physical twin) both of which are interconnected via exchange of data in real time. Conceptually, a DT mimics the state of its physical twin in real time and vice versa. Application of DT includes real-time monitoring, designing/planning, optimization, maintenance, remote access, etc. Its implementation is expected to grow exponentially in the coming decades. The advent of Industry 4.0 has brought complex industrial systems that are more autonomous, smart, and highly interconnected. These systems generate considerable amounts of data useful for several applications such as improving performance, predictive maintenance, training, etc. A sudden influx in the number of publications related to ‘Digital Twin’ has led to confusion between different terminologies related to the digitalization of industries. Another problem that has arisen due to the growing popularity of DT is a lack of consensus on the description of DT as well as so many different types of DT, which adds to the confusion. This paper intends to consolidate the different types of DT and different definitions of DT throughout the literature for easy identification of DT from the rest of the complimentary terms such as ‘product avatar’, ‘digital thread’, ‘digital model’, and ‘digital shadow’. The paper looks at the concept of DT since its inception to its predicted future to realize the value it can bring to certain sectors. Understanding the characteristics and types of DT while weighing its pros and cons is essential for any researcher, business, or sector before investing in the technology.
  • 11.9K
  • 25 Jun 2021
Topic Review
Types of Transcatheter Aortic Valve Replacement Devices
Transcatheter aortic valve replacement (TAVR) was originally conceptualized in the early 1990s, largely inspired by the pioneering experiences in the field of percutaneous transluminal coronary angioplasty.
  • 11.9K
  • 03 Aug 2022
Topic Review
Testing Effect
The testing effect is the finding that long-term memory is often increased when some of the learning period is devoted to retrieving the to-be-remembered information. The effect is also sometimes referred to as retrieval practice, practice testing, or test-enhanced learning. Retrieval practice may be the best way to refer to the testing effect because the benefits of retrieval-related testing are not limited to tests. It can be more broad, including tools like flash cards and quizzes. The testing effect on memory should be distinguished from more general practice effects, defined in the APA Dictionary of Psychology (2007) as "any change or improvement that results from practice or repetition of task items or activities." The term testing effect is also sometimes used in a more general sense; The Oxford Dictionary of Psychology (2003) defines a testing effect as "any effect of taking tests on the respondents, a typical example being test sophistication." Whereas psychologists who develop tests for personality and intelligence want to avoid practice effects, cognitive psychologists working with educators have begun to understand how to take advantage of tests—not as an assessment tool, but as a teaching/learning tool. It is useful for people to test their knowledge of the to-be-remembered material during the learning process, instead of only reading or otherwise passively studying the material. For example, a student can use flashcards to self-test and receive feedback as they study. The testing effect provides a larger benefit to long-term memory when the tested material is difficult enough to require effort, the rate of retrieval success is high, and feedback with correct answers is given after testing. The testing effect is activated by active recall.
  • 11.8K
  • 20 Oct 2022
Topic Review
Humid Subtropical Climate
A humid subtropical climate is a zone of climate characterized by hot, humid summers, and cool to mild winters. These climates normally lie on the southeast side of all continents, generally between latitudes 25° and 35° and are located poleward from adjacent tropical climates. While many subtropical climates tend to be located at or near coastal locations, in some cases they extend inland, most notably in China and the United States , where they exhibit more pronounced seasonal variations and sharper contrasts between summer and winter, as part of a gradient between the more tropical climates of the southern coasts of these countries and the more continental climates of China and the United States ' northern and central regions (localities around the Ohio and Yangtze rivers exhibiting continental influence from the north, compared to climates around the Gulf of Mexico and the South China Sea, which exhibit tropical influence due to their southern coastal positions). The humid subtropical climate classification was officially created under the Trewartha Climate classification. Trewartha attempted to redefine middle latitude climates in the Koppen system since many climatologists argued that his "C" climate zone was too broad. Trewartha attempted to separate the middle latitude in three zones (subarctic, temperate, and subtropical). In this classification, climates are termed humid subtropical when they have at least 8 months with a mean temperature above 10 °C (50 °F). Under the Holdridge life zones classification, the subtropical climates have a biotemperature between the frost or critical temperature line, 16 to 18 °C (61 to 64 °F) (depending on locations in the world) and 24 °C (75 °F), and these climates are humid (or even perhumid or superhumid) when the potential evapotranspiration (PET) ratio (= PET / Precipitation) is less than 1. In the Holdridge classification, the humid subtropical climates coincide more or less with the warmest Cfa and Cwa climates and the less warm humid tropical "Köppen" climates (Aw, Am and Af). In a humid subtropical climate, summers are typically long, hot and humid. Monthly mean summer temperatures are normally between 24 and 27 °C (75 and 81 °F). A deep current of tropical air dominates the humid subtropics at the time of high sun, and daily intense (but brief) convective thundershowers are common. Summer high temperatures are typically in the high 20s to mid-30s °C (80s or 90s °F), while overnight lows in the summer are typically in the lower 20s °C (70s °F). Monthly mean temperatures in winter are often mild, typically averaging 7.5 to 16 °C (45.5 to 60.8 °F). Daytime highs in winter normally are in the 10 to 16 °C (50 to 61 °F) range, while overnight lows are from 2 to 7 °C (36 to 45 °F), though the poleward boundaries of this climate feature colder temperatures. Rainfall often shows a summer peak, especially where monsoons are well developed, as in Southeast Asia and South Asia. Other areas have a more uniform or varying rainfall cycles, but consistently lack any predictably dry summer months. Most summer rainfall occurs during thunderstorms that build up due to the intense surface heating and strong subtropical sun angle. Weak tropical lows that move in from adjacent warm tropical oceans, as well as infrequent tropical storms often contribute to summer seasonal rainfall peaks. Winter rainfall is often associated with large storms in the westerlies that have fronts that reach down into subtropical latitudes. However, many subtropical climates such as southeast Asia and Florida in the United States have very dry winters, with frequent brush fires and water shortages.
  • 11.8K
  • 01 Dec 2022
Topic Review
Hyperspectral Remote Sensing
Hyperspectral imaging is an incorporation of the modern imaging system and traditional spectroscopy technology. Unmanned aerial vehicle (UAV) hyperspectral imaging techniques have recently emerged as a valuable tool in agricultural remote sensing, with tremendous promise for many application such as weed detection and species separation
  • 11.8K
  • 21 Mar 2022
Topic Review
Queer Theory
Queer theory is a field of critical theory that emerged in the early 1990s out of the fields of queer studies and women's studies. Queer theory includes both queer readings of texts and the theorization of 'queerness' itself. Heavily influenced by the work of Lauren Berlant, Leo Bersani, Judith Butler, Lee Edelman, Jack Halberstam, and Eve Kosofsky Sedgwick, queer theory builds both upon feminist challenges to the idea that gender is part of the essential self and upon gay/lesbian studies' close examination of the socially constructed nature of sexual acts and identities. Whereas gay/lesbian studies focused its inquiries into natural and unnatural behavior with respect to homosexual behavior, queer theory expands its focus to encompass any kind of sexual activity or identity that falls into normative and deviant categories. Italian feminist and film theorist Teresa de Lauretis coined the term "queer theory" for a conference she organized at the University of California, Santa Cruz in 1990 and a special issue of Differences: A Journal of Feminist Cultural Studies she edited based on that conference. Through the context of heterosexuality being the origin and foundation of society’s heteronormative stability, the concept of queerness focuses on, “mismatches between sex, gender and desire” Queerness has been associated most prominently with bisexual, lesbian and gay subjects, but its analytic framework also includes such topics as cross-dressing, intersex bodies and identities, gender ambiguity and gender-corrective surgery. Queer theory holds that individual sexuality is a fluid, fragmented, and dynamic collectivity of possible sexualities and it may vary at different points of his life. Its attempted debunking of stable (and correlated) sexes, genders, and sexualities develops out of the specifically lesbian and gay reworking of the post-structuralist figuring of identity as a constellation of multiple and unstable positions. Queer theory also examines the discourses of homosexuality developed in the last century in order to place the "queer" into historical context, deconstructing contemporary arguments both for and against this latest terminology.
  • 11.8K
  • 17 Oct 2022
Biography
Eckhart Tolle
Eckhart Tolle (/ˈɛkɑːrt ˈtɒlə/ EK-art TOL-ə; German: [ˈɛkhaʁt ˈtɔlə]; born Ulrich Leonard Tölle, February 16, 1948) is a German spiritual teacher and self-help author best known as the author of The Power of Now and A New Earth: Awakening to Your Life's Purpose. After being recommended by Oprah Winfrey, his first book, The Power of Now,[1] reached The New York Times Best Seller l
  • 11.8K
  • 05 Dec 2022
Topic Review
Criticisms of Neoclassical Economics
Neo-classical economics has come under critique on the basis of its core ideologies, assumptions, and other matters.
  • 11.8K
  • 29 Nov 2022
Topic Review
Quadruple and Quintuple Innovation Helix (Q2IH) Framework
The quadruple along with the quintuple innovation helix framework was co-developed by Elias G. Carayannis and David F.J. Campbell, with the quadruple helix being described in a 2009 article and the quintuple helix in a 2010 article. It extends and expands substantially the triple helix model of innovation economics as the framework introduces civil society and the environment as pillars and focal points of policy and practice. In particular, civil society emphasizes the role of bottom-up initiatives complementing top-down government, university and industry policies and practices, and the environment emphasizes the sustainability priorities and exigencies that need to inform and moderate top-down policies and practices as well as bottom-up initiatives. Within the quintuple helix, these represent the sine qua non of smart, sustainable and inclusive growth. The quintuple helix views the natural environments of society and the economy as drivers for knowledge production and innovation, thus defining opportunities for the knowledge society and knowledge economy. The quintuple helix can be described in terms of the models of knowledge that it extends, the five subsystems (helices) it incorporates, and the steps involved in the circulation of knowledge. How to define these new helices has been debated and some researchers see them as additional helices while some see them as different types of helix which overarch the previous helices.
  • 11.8K
  • 22 Nov 2022
Topic Review
Clay Bricks
Clay bricks are extensively used as building material worldwide. Natural soil deposits are in constant reduction due to the frequent use of clay to manufacture bricks. About 1600 billion bricks are produced annually by the consumption of millions of tons of natural resources.
  • 11.7K
  • 18 Sep 2021
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