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Topic Review
Wind Turbines
Wind turbines (WTs) are large devices utilized to convert the wind's kinetic energy into electricity. There are several different typologies of WTs, the most common type being the so-called Horizontal Axis Wind Turbine (HAWT) systems. In this configuration, the rotation axis of the rotor is parallel to the ground. Specific attention must be paid to the orientation with respect to the wind direction, which is different from other types of wind turbines such as those with a vertical axis (VAWT), whose orientation is independent of the prevailing wind direction. For HAWT, the three-bladed upwind configuration is the most common one, with the rotor facing the incoming wind. WTs can be deployed both on- or offshore and have very different blade lengths, which result in different sizes (especially regarding the tower height) and power output. Due to fatigue and exposure to outdoor elements, WT monitoring and diagnostics are strictly needed to reduce structural and mechanical failure and achieve cost-effective energy production. This requires both the Structural Health Monitoring of the WTs load-bearing components (tower, blades, foundations, etc) and the Condition Monitoring of their mechanical parts (gearbox, generator, etc).
  • 7.8K
  • 02 Mar 2022
Topic Review
Andhaka
In Hindu mythology, Andhaka (Sanskrit: अन्धक, IAST: andhaka, lit. he who darkens) often refer to a malevolent asura who is killed by Shiva for trying to abduct Parvati. His story finds mention in various Hindu texts, including Matsya Purana, Kurma Purana, Linga Purana and Shiva Purana. He is believed to have thousand heads, two thousand eyes, arms and feet.
  • 7.8K
  • 17 Oct 2022
Topic Review
Physiology of Plant Responses to Water Stress
Drought and waterlogging seriously affect the growth of plants and are considered severe constraints on agricultural and forestry productivity; their frequency and degree have increased over time due to global climate change. The morphology, photosynthetic activity, antioxidant enzyme system and hormone levels of plants could change in response to water stress. 
  • 7.8K
  • 23 May 2022
Topic Review
Time Synchronization
Time (or clock) synchronization is a large and vital field of research, as synchronization is a precondition for many applications. A few example applications are distributed data acquisition, distributed databases, and real-time communication.
  • 7.7K
  • 08 Dec 2020
Topic Review
Peace Treaty
A peace treaty is an agreement between two or more hostile parties, usually countries or governments, which formally ends a state of war between the parties. It is different from an armistice, which is an agreement to stop hostilities; a surrender, in which an army agrees to give up arms; or a ceasefire or truce, in which the parties may agree to temporarily or permanently stop fighting. The art of negotiating a peace treaty in the modern era has been referred to by legal scholar Christine Bell as the lex pacificatoria, with a peace treaty potentially contributing to the legal framework governing the post conflict period, or jus post bellum.
  • 7.7K
  • 12 Oct 2022
Topic Review
Old Spanish Language
Old Spanish, also known as Old Castilian (Spanish: castellano antiguo; Template:Lang-osp [roˈmantse kasteˈʎano]) or Medieval Spanish (Spanish: español medieval), was originally a colloquial Latin spoken in the provinces of the Roman Empire that provided the root for the early form of the Spanish language that was spoken on the Iberian Peninsula from the 10th century until roughly the beginning of the 15th century, before a consonantal readjustment gave rise to the evolution of modern Spanish. The poem Cantar de Mio Cid (The Poem of the Cid), published around 1200, remains the best known and most extensive work of literature in Old Spanish.
  • 7.7K
  • 26 Oct 2022
Topic Review
Analysis of Business Efficiency
Measuring efficiency and identifying the sources of potential inefficiency in particular are very important steps in improving the competitive position of the enterprises in their continuous development, sustainability, overall behavior in the current corporate environment and security aspects. 
  • 7.7K
  • 28 Jan 2022
Topic Review
Realigning Election
In political science and political history, a realigning election (often called a critical election, political realignment, or critical realignment) is a set of sharp changes in party ideology, issues, party leaders, regional and demographic bases of power of political parties, and the structure or rules of the political system, such as voter eligibility or financing. The changes result in a new political power structure that lasts for decades, replacing an older dominant coalition. Scholars frequently invoke the concept in American elections and occasionally those of other countries. US examples include the 1896 presidential election, when the issues of the Civil War political system were replaced with those of the Populist and Progressive Era, and the 1932 election, when the Populist and Progressive Eras were replaced by the New Deal issues of New Deal liberalism and modern conservatism. Realigning elections typically separate (what are known in the field of comparative politics as) party systems—with 1828, for example, separating the First Party System and the Second Party System in the US. It is generally accepted that the United States has had five distinct party systems, each featuring two major parties attracting a consistent political coalition and following a consistent party ideology, separated by four realignments. Political realignments can be sudden (1–4 years) or can take place more gradually (5–20 years). Most often, however, particularly in V. O. Key Jr.'s (1955) original hypothesis, it is a single "critical election" that marks a realignment. By contrast, a gradual process is called a secular realignment. Political scientists and historians often disagree about which elections are realignments and what defines a realignment, and even whether realignments occur. The terms themselves are somewhat arbitrary, however, and usage among political scientists and historians does vary. In the US, Walter Dean Burnham argued for a 30–38 year "cycle" of realignments. Many of the elections often included in the Burnham 38-year cycle are considered "realigning" for different reasons. Other political scientists and quantitative elections analysts reject realignment theory altogether, arguing that there are no long-term patterns. Political scientist David R. Mayhew states, "Electoral politics is to an important degree just one thing after another ... Elections and their underlying causes are not usefully sortable into generation-long spans ... It is a Rip Van Winkle view of democracy that voters come awake only once in a generation ... It is too slippery, too binary, too apocalyptic, and it has come to be too much of a dead end." Sean Trende, senior elections analyst at RealClearPolitics, who argues against realignment theory and the "emerging Democratic majority" thesis proposed by journalist John Judis and political scientist Ruy Teixeira in his 2012 book The Lost Majority states, "Almost none of the theories propounded by realignment theorists has endured the test of time... It turns out that finding a 'realigning' election is a lot like finding an image of Jesus in a grilled-cheese sandwich – if you stare long enough and hard enough, you will eventually find what you are looking for." In May 2015, statistician and FiveThirtyEight editor-in-chief Nate Silver argued against a blue wall Electoral College advantage for the Democratic Party in the upcoming 2016 US presidential election, and in post-election analysis published in January 2017, Silver cited Trende in noting that "there are few if any permanent majorities" and both Silver and Trende argued that the "emerging Democratic majority" thesis led most news coverage and commentary preceding the election to overstate Hillary Clinton's chances of being elected.
  • 7.7K
  • 17 Nov 2022
Topic Review
Copper(II) Complex
A dinuclear copper(II) complex of (1) (where bipy = 2,2′‑bipyridine, bzt = benzoate and ox = oxalate) was synthesised and characterised by diffractometric (powder and single-crystal XRD) and thermogravimetric (TG/DTG) analyses, spectroscopic techniques (IR, Raman, electron paramagnetic resonance spectroscopy (EPR) and electronic spectroscopy), magnetic measurements and density functional theory (DFT) calculations. The analysis of the crystal structure revealed that the oxalate ligand is in bis(bidentate) coordination mode between two copper(II) centres. The other four positions of the coordination environment of the copper(II) ion are occupied by one water molecule, a bidentate bipy and a monodentate bzt ligand. An inversion centre located on the ox ligand generates the other half of the dinuclear complex. Intermolecular hydrogen bonds and pi-pi for the organisation of the molecules in the solid state. Molar magnetic susceptibility and field dependence magnetisation studies evidenced a weak intramolecular–ferromagnetic interaction (J = +2.9 cm‑1) between the metal ions. The sign and magnitude of the calculated J value by density functional theory (DFT) are in agreement with the experimental data.
  • 7.7K
  • 30 Oct 2020
Topic Review
Virus Elimination in Plants
Virus elimination from plants is mostly based on the in vitro culture of isolated meristem, and in addition thermotherapy, chemotherapy, electrotherapy, and cryotherapy can also be applied. Treatments can result in low rate of survival, inhibited growth, incomplete development, or abnormal morphology.  The rate of destruction depends on the genotypes and physiological condition of plants. There are several ways to decrease the harmful effect of treatments. 
  • 7.7K
  • 31 May 2021
Topic Review
Brainstem Encephalitis
Brainstem encephalitis refers to inflammatory diseases affecting the midbrain, pons, and medulla oblongata. The causes of brainstem encephalitis include infections, autoimmune diseases, and paraneoplastic syndromes. Listeria is a common etiology of infectious rhombencephalitis. The trigeminal nerve has been proposed as a pathway through which Listeria monocytogenes reaches the brainstem after entering damaged oropharyngeal mucosa or periodontal tissues. Listeria monocytogenes may also invade the brainstem along the vagus nerve after it infects enteric neurons in the walls of the gastrointestinal tract.
  • 7.7K
  • 22 Oct 2020
Topic Review
Sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) mineral particles or rock fragments. Most sandstone is composed of quartz or feldspar (both silicates) because they are the most resistant minerals to weathering processes at the Earth's surface, as seen in Bowen's reaction series. Like uncemented sand, sandstone may be any color due to impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions. Rock formations that are primarily composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Fine-grained aquifers, such as sandstones, are better able to filter out pollutants from the surface than are rocks with cracks and crevices, such as limestone or other rocks fractured by seismic activity. Quartz-bearing sandstone can be converted into quartzite through metamorphism, usually related to tectonic compression within orogenic belts.
  • 7.7K
  • 15 Nov 2022
Topic Review
Integrated On-Board Charger-Traction Systems
The Integrated On-board Charger (iOBC) is the innovative technique to design the on-board charging system in which the motor coil and traction inverter is used during charging as grid filter and active front-end power factor correction unit respectively. This technique helps to increase charging power density, reduce vehicle size and weight.
  • 7.7K
  • 17 Aug 2022
Topic Review
Quantum Vacuum Thruster
A quantum vacuum thruster (QVT or Q-thruster) is a theoretical system hypothesized to use the same principles and equations of motion that a conventional plasma thruster would use, namely magnetohydrodynamics (MHD), to make predictions about the behavior of the propellant. However, rather than using a conventional plasma as a propellant, a QVT would interact with quantum vacuum fluctuations of the zero-point field. The concept is controversial and generally not considered physically possible. However, if QVT systems were possible they could eliminate the need to carry propellant, being limited only by the availability of energy.
  • 7.7K
  • 11 Oct 2022
Topic Review
V-Models for the Development Procedures and Functional Safety
The design of modern industrial products is further improved through the hardware-in-the-loop (HIL) simulation. An HIL model can bypass serious damage to the real object, reduce debugging cost, and, finally, reduce the comprehensive effort during the testing.
  • 7.7K
  • 29 Aug 2022
Topic Review Video
Risk Management in Information Systems
Businesses are bombarded with great deals of risks, vulnerabilities, and unforeseen business interruptions in their lifetime, which negatively affect their productivity and sustainability within the market. Such risks require a risk management system to identify risks and risk factors and propose approaches to eliminate or reduce them. Risk management involves highly structured practices that should be implemented within an organization, including organizational planning documents. Continuity planning and fraud detection policy development are among the many critically important practices conducted through risk management that aim to mitigate risk factors, their vulnerability, and their impact. Information systems play a pivotal role in any organization by providing many benefits, such as reducing human errors and associated risks owing to the employment of sophisticated algorithms. Both the development and establishment of an information system within an organization contributes to mitigating business-related risks and also creates new types of risks associated with its establishment. Businesses must prepare for, react to, and recover from unprecedented threats that might emerge in the years or decades that follow.
  • 7.7K
  • 15 Dec 2021
Topic Review
Lost Lands
Lost lands can be continents, islands or other regions existing during prehistory, having since disappeared as a result of catastrophic geological phenomena or slowly rising sea levels since the end of the last Ice Age. Lost lands, where they existed, are supposed to have subsided into the sea, leaving behind only a few traces or legends. The term can also be extended to mythological lands generally, to underground civilizations, or even to whole planets. The classification of lost lands as continents, islands, or other regions is in some cases subjective; for example, Atlantis is variously described as either a "lost island" or a "lost continent". Lost land theories may originate in mythology or philosophy, or in scholarly or scientific theories, such as catastrophic theories of geology.
  • 7.7K
  • 11 Oct 2022
Topic Review
Extraction of Peanut Skins
In addition to the edible kernel, the peanut seed consists of the woody outer shell and a paper-like substance that surrounds the kernel itself known as the testa or skin.
  • 7.7K
  • 28 Jan 2021
Topic Review
Support Vector Machine
In machine learning, support-vector machines (SVMs, also support-vector networks) are supervised learning models with associated learning algorithms that analyze data used for classification and regression analysis. The Support Vector Machine (SVM) algorithm is a popular machine learning tool that offers solutions for both classification and regression problems. Developed at AT&T Bell Laboratories by Vapnik with colleagues (Boser et al., 1992, Guyon et al., 1993, Vapnik et al., 1997), it presents one of the most robust prediction methods, based on the statistical learning framework or VC theory proposed by Vapnik and Chervonekis (1974) and Vapnik (1982, 1995). Given a set of training examples, each marked as belonging to one or the other of two categories, an SVM training algorithm builds a model that assigns new examples to one category or the other, making it a non-probabilistic binary linear classifier (although methods such as Platt scaling exist to use SVM in a probabilistic classification setting). An SVM model is a representation of the examples as points in space, mapped so that the examples of the separate categories are divided by a clear gap that is as wide as possible. New examples are then mapped into that same space and predicted to belong to a category based on the side of the gap on which they fall. In addition to performing linear classification, SVMs can efficiently perform a non-linear classification using what is called the kernel trick, implicitly mapping their inputs into high-dimensional feature spaces. When data are unlabelled, supervised learning is not possible, and an unsupervised learning approach is required, which attempts to find natural clustering of the data to groups, and then map new data to these formed groups. The support-vector clustering algorithm, created by Hava Siegelmann and Vladimir Vapnik, applies the statistics of support vectors, developed in the support vector machines algorithm, to categorize unlabeled data, and is one of the most widely used clustering algorithms in industrial applications.
  • 7.7K
  • 14 Oct 2022
Topic Review
Snake Dry Bites
Snake ‘dry bites’ are characterized by the absence of venom being injected into the victim during a snakebite incident. The dry bite mechanism and diagnosis are quite complex, and the lack of envenoming symptoms in these cases may be misinterpreted as a miraculous treatment or as proof that the bite from the perpetrating snake species is rather harmless.
  • 7.7K
  • 01 Dec 2020
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