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Topic Review
Triply Periodic Minimal Surfaces Thermal Hydraulic Effects
Triply Periodic Minimal Surfaces (TPMS) are a kind of periodic implicit surface with zero mean curvature, that is, the surfaces that locally minimize surface area for a given boundary. The TPMS is composed of infinite, non-self-intersecting, periodic surfaces in three principal directions. The TPMS networks as repeated lattice structures have attracted much research interest because they have shown better mechanical performance, mass transfer, and thermal conductivity than conventional and strut-based structures, which have been employed in different disciplines. With excellent performances in the TPMS architectures, current works have investigated the TPMS structures to utilize in a wide range of applications.
  • 12.2K
  • 29 Dec 2022
Topic Review
Palm Kernel Cake for Poultry
Palm kernel cake (PKC), a by-product of oil extracted from palm nuts through expeller press or solvent extraction procedures is one of the highest quantities of locally available and potentially inexpensive agricultural products. PKC provides approximately 14–18% of crude protein (CP), 12–20% crude fiber (CF), 3–9% ether extract (EE), and different amounts of various minerals that feasible to be used as a partial substitute of soybean meal (SBM) and corn in poultry nutrition. Poultry’s digestibility is reported to be compromised due to the indigestion of the high fiber content, making PKC potentially low for poultry feeding. Nevertheless, solid-state fermentation (SSF) can be applied to improve the nutritional quality of PKC by improving the CP and reducing CF content. PKC also contains β-mannan polysaccharide, which works as a prebiotic.
  • 12.2K
  • 07 Mar 2021
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
  • 12.1K
  • 18 Nov 2022
Topic Review
Duchy
A duchy is a medieval country, territory, fief, or domain ruled by a duke or duchess, a high-ranking nobleman hierarchically second to the king or queen in European tradition. The term is used almost exclusively in Europe, where in the present day there is no sovereign duchy (i.e. with the status of a nation state) left. The term "duke" (like the corresponding "duchy") should not be confused with the title Grand Duke (or Grand Duchy, such as the present-day Grand Duchy of Luxembourg), as there exists a significant difference of rank between the two. In common European cultural heritage, a grand duke is the third highest monarchic rank, after emperor and king. Its synonym in many Slavic and Baltic European languages (Russian, Lithuanian, etc.) is translated as Grand Prince, whereas most Germanic and Romance European languages (English, French, Spanish, Italian etc.) use expressions corresponding to Grand Duke. Unlike a duke, the sovereign grand duke is considered royalty (or in German, 'royal nobility', Königsadel). The proper form of address for a grand duke is His Royal Highness (HRH), whereas for a non-royal duke in the United Kingdom it is His Grace. In contrast to this, the rank of a duke differs from one country to the next. In Germany, for example, a duke is listed in the aristocratic hierarchy below an emperor (Kaiser), king (König), grand duke (Großherzog), and elector (Kurfürst) – in that order – whereas in Britain the duke comes third after king/queen and prince (there are no British grand dukes or electors). In all countries, there existed an important difference between "sovereign dukes" and dukes subordinate to a king or emperor. Some historic duchies were sovereign in areas that would become part of nation-states only during the modern era, such as Germany (a federal empire) and Italy (a unified kingdom). In contrast, others were subordinate districts of those kingdoms that had unified either partially or completely during the medieval era, such as France, Spain, Sicily, Naples, and the Papal States. In England, the term is used in respect of non-territorial entities.
  • 12.1K
  • 09 Oct 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.
  • 12.1K
  • 08 Nov 2022
Topic Review
Law
Law is a system of rules that are created and enforced through social or governmental institutions to regulate behavior. Law is a system that regulates and ensures that individuals or a community adhere to the will of the state. State-enforced laws can be made by a collective legislature or by a single legislator, resulting in statutes, by the executive through decrees and regulations, or established by judges through precedent, normally in common law jurisdictions. Private individuals can create legally binding contracts, including arbitration agreements that may elect to accept alternative arbitration to the normal court process. The formation of laws themselves may be influenced by a constitution, written or tacit, and the rights encoded therein. The law shapes politics, economics, history and society in various ways and serves as a mediator of relations between people. A general distinction can be made between (a) civil law jurisdictions, in which a legislature or other central body codifies and consolidates their laws, and (b) common law systems, where judge-made precedent is accepted as binding law. Historically, religious laws played a significant role even in settling of secular matters, and is still used in some religious communities. Islamic Sharia law is the world's most widely used religious law, and is used as the primary legal system in some countries, such as Iran and Saudi Arabia. The adjudication of the law is generally divided into two main areas. Criminal law deals with conduct that is considered harmful to social order and in which the guilty party may be imprisoned or fined. Civil law (not to be confused with civil law jurisdictions above) deals with the resolution of lawsuits (disputes) between individuals or organizations. Law provides a source of scholarly inquiry into legal history, philosophy, economic analysis and sociology. Law also raises important and complex issues concerning equality, fairness, and justice.
  • 12.1K
  • 25 Oct 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.
  • 12.1K
  • 22 Nov 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.
  • 12.0K
  • 20 Aug 2020
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
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.
  • 12.0K
  • 08 Jul 2022
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.
  • 12.0K
  • 27 Oct 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.
  • 12.0K
  • 17 Oct 2022
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
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.
  • 12.0K
  • 25 Jun 2021
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.
  • 12.0K
  • 19 Apr 2021
Topic Review
Insulin Signaling
The insulin signaling pathway begins with the binding of the peptide hormone insulin to its corresponding receptor, the insulin receptor. The insulin receptor is a receptor tyrosine kinase (RTK) that conformationally consists of two alpha and two beta subunit tetramers. The insulin receptor exhibiting kinase activity is responsible for its autophosphorylation at the tyrosine residue site upon insulin binding.
  • 12.0K
  • 28 Sep 2021
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
  • 12.0K
  • 21 Mar 2022
Biography
Ben Shapiro
Benjamin Aaron Shapiro (born January 15, 1984)[1] is an American conservative political commentator, public speaker, media executive, author, and attorney. At age 17, he became the youngest nationally syndicated columnist in the United States.[2][3][4] He writes columns for Creators Syndicate and Newsweek, serves as editor-in-chief for The Daily Wire, which he founded, and hosts The Ben Shapiro
  • 11.9K
  • 06 Dec 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.
  • 11.9K
  • 01 Dec 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
  • 11.9K
  • 05 Dec 2022
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