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Topic Review
Parental Involvement
Parental involvement is seen as an important strategy for the advancement of the quality of education. The ultimate objective of this is to expand the academic and social capacities of students, especially those of disadvantaged backgrounds determined by ethnic minority origin and low socio-economic status. In this contribution, various forms of both parental and school-initiated involvement will be described. In addition, results of studies into the effectiveness of parental involvement will be presented.
  • 8.4K
  • 15 Nov 2021
Topic Review Peer Reviewed
Natural Disasters: Origins, Impacts, Management
Natural hazards are processes that serve as triggers for natural disasters. Natural hazards can be classified into six categories. Geophysical or geological hazards relate to movement in solid earth. Their examples include earthquakes and volcanic activity. Hydrological hazards relate to the movement of water and include floods, landslides, and wave action. Meteorological hazards are storms, extreme temperatures, and fog. Climatological hazards are increasingly related to climate change and include droughts and wildfires. Biological hazards are caused by exposure to living organisms and/or their toxic substances. The COVID-19 virus is an example of a biological hazard. Extraterrestrial hazards are caused by asteroids, meteoroids, and comets as they pass near earth or strike earth. In addition to local damage, they can change earth inter planetary conditions that can affect the Earth’s magnetosphere, ionosphere, and thermosphere. This entry presents an overview of origins, impacts, and management of natural disasters. It describes processes that have potential to cause natural disasters. It outlines a brief history of impacts of natural hazards on the human built environment and the common techniques adopted for natural disaster preparedness. It also lays out challenges in dealing with disasters caused by natural hazards and points to new directions in warding off the adverse impact of such disasters. 
  • 8.4K
  • 13 Apr 2022
Topic Review
Slope Stability Analysis
Slope stability analysis is performed to assess the safe design of a human-made or natural slopes (e.g. embankments, road cuts, open-pit mining, excavations, landfills etc.) and the equilibrium conditions. Slope stability is the resistance of inclined surface to failure by sliding or collapsing. The main objectives of slope stability analysis are finding endangered areas, investigation of potential failure mechanisms, determination of the slope sensitivity to different triggering mechanisms, designing of optimal slopes with regard to safety, reliability and economics, designing possible remedial measures, e.g. barriers and stabilization. Successful design of the slope requires geological information and site characteristics, e.g. properties of soil/rock mass, slope geometry, groundwater conditions, alternation of materials by faulting, joint or discontinuity systems, movements and tension in joints, earthquake activity etc. The presence of water has a detrimental effect on slope stability. Water pressure acting in the pore spaces, fractures or other discontinuities in the materials that make up the pit slope will reduce the strength of those materials. Choice of correct analysis technique depends on both site conditions and the potential mode of failure, with careful consideration being given to the varying strengths, weaknesses and limitations inherent in each methodology. Before the computer age stability analysis was performed graphically or by using a hand-held calculator. Today engineers have a lot of possibilities to use analysis software, ranges from simple limit equilibrium techniques through to computational limit analysis approaches (e.g. Finite element limit analysis, Discontinuity layout optimization) to complex and sophisticated numerical solutions (finite-/distinct-element codes). The engineer must fully understand limitations of each technique. For example, limit equilibrium is most commonly used and simple solution method, but it can become inadequate if the slope fails by complex mechanisms (e.g. internal deformation and brittle fracture, progressive creep, liquefaction of weaker soil layers, etc.). In these cases more sophisticated numerical modelling techniques should be utilised. Also, even for very simple slopes, the results obtained with typical limit equilibrium methods currently in use (Bishop, Spencer, etc.) may differ considerably. In addition, the use of the risk assessment concept is increasing today. Risk assessment is concerned with both the consequence of slope failure and the probability of failure (both require an understanding of the failure mechanism). Within the last decade (2003) Slope Stability Radar has been developed to remotely scan a rock slope to monitor the spatial deformation of the face. Small movements of a rough wall can be detected with sub-millimeter accuracy by using interferometry techniques.
  • 8.4K
  • 19 Oct 2022
Topic Review
The Sims 2 Stuff Packs
Stuff packs are minor expansion packs for The Sims 2 that add new items, clothing, and furniture to the game without implementing any significant changes to gameplay.
  • 8.4K
  • 17 Nov 2022
Topic Review
Cyrillic Script
The Cyrillic script (/sɪˈrɪlɪk/ sə-RIL-ik) is a writing system used for various languages across Eurasia and is used as the national script in various Slavic, Turkic, Mongolic, Uralic, Caucasian and Iranic-speaking countries in Southeastern Europe, Eastern Europe, the Caucasus, Central Asia, North Asia and East Asia. (As of 2019), around 250 million people in Eurasia use Cyrillic as the official script for their national languages, with Russia accounting for about half of them. With the accession of Bulgaria to the European Union on 1 January 2007, Cyrillic became the third official script of the European Union, following the Latin and Greek alphabets. In the 9th century AD, the Bulgarian tsar Simeon I the Great – following the cultural and political course of his father Boris I – commissioned a new script, the Early Cyrillic alphabet, to be made at the Preslav Literary School in the First Bulgarian Empire, which would replace the Glagolitic script, produced earlier by Saints Cyril and Methodius and the same disciples that created the new Slavic script in Bulgaria. The usage of the Cyrillic script in Bulgaria was made official in 893. The new script became the basis of alphabets used in various languages, especially those of Orthodox Slavic origin, and non-Slavic languages influenced by Bulgarian. For centuries Cyrillic was used by Catholic and Muslim Slavs too (see Bosnian Cyrillic). Cyrillic is derived from the Greek uncial script, augmented by letters from the older Glagolitic alphabet, including some ligatures. These additional letters were used for Old Church Slavonic sounds not found in Greek. The script is named in honor of the Saint Cyril, one of the two Byzantine brothers, Saints Cyril and Methodius, who created the Glagolitic alphabet earlier on. Modern scholars believe that Cyrillic was developed and formalized by the early disciples of Cyril and Methodius in the Preslav Literary School, the most important early literary and cultural centre of the First Bulgarian Empire and of all Slavs. The school developed the Cyrillic script: The earliest datable Cyrillic inscriptions have been found in the area of Preslav. They have been found in the medieval city itself, and at nearby Patleina Monastery, both in present-day Shumen Province, in the Ravna Monastery and in the Varna Monastery. With the orthographic reform of Saint Evtimiy of Tarnovo and other prominent representatives of the Tarnovo Literary School (14th and 15th centuries) such as Gregory Tsamblak or Constantine of Kostenets the school influenced Russian, Serbian, Wallachian and Moldavian medieval culture. That is famous in Russia as the second South-Slavic influence. In the early 18th century, the Cyrillic script used in Russia was heavily reformed by Peter the Great, who had recently returned from his Grand Embassy in Western Europe. The new letterforms, called the Civil script, became closer to those of the Latin alphabet; several archaic letters were abolished and several letters were designed by Peter himself. Letters became distinguished between upper and lower case. West European typography culture was also adopted. The pre-reform forms of letters called 'Полуустав' were notably kept for use in Church Slavonic and are sometimes used in Russian even today, especially if one wants to give a text a 'Slavic' or 'archaic' feel.
  • 8.3K
  • 22 Nov 2022
Topic Review
Segmentation
Segmentation in biology is the division of some animal and plant body plans into a series of repetitive segments. This article focuses on the segmentation of animal body plans, specifically using the examples of the taxa Arthropoda, Chordata, and Annelida. These three groups form segments by using a "growth zone" to direct and define the segments. While all three have a generally segmented body plan and use a growth zone, they use different mechanisms for generating this patterning. Even within these groups, different organisms have different mechanisms for segmenting the body. Segmentation of the body plan is important for allowing free movement and development of certain body parts. It also allows for regeneration in specific individuals.
  • 8.3K
  • 29 Sep 2022
Topic Review
Perovskite Materials
In the development of hydrogen-based technology, a key challenge is the sustainable production of hydrogen in terms of energy consumption and environmental aspects. However, existing methods mainly rely on fossil fuels due to their cost efficiency, and as such, it is difficult to be completely independent of carbon-based technology. Electrochemical hydrogen production is essential, since it has shown the successful generation of hydrogen gas of high purity. Similarly, the photoelectrochemical (PEC) method is also appealing, as this method exhibits highly active and stable water splitting with the help of solar energy. We discuss the exceptional optical and electrical characteristics of perovskite materials which often dictate PEC performance. We further extend our discussion to the material limit of perovskite under a hydrogen production environment, i.e., that PEC reactions often degrade the contact between the electrode and the electrolyte.
  • 8.3K
  • 30 Jul 2021
Topic Review
Classical Nucleation Theory
Crystal nucleation determining the formation and assembly pathway of first organic materials is the central science of various scientific disciplines such as chemical, geochemical, biological, and synthetic materials. Classical nucleation theory (CNT)  applies to systems of small organic molecules with an emphasis on the molecular interpretation of nucleation kinetics. CNT holds that density fluctuations are concomitant with the development of crystalline order. In other words, a crystal nucleus has an identical structure to its bulk crystal. 
  • 8.3K
  • 22 Jul 2022
Topic Review
History of Democratic Socialism
Democratic socialism represents the modernist development of socialism and its outspoken support for democracy. The origins of democratic socialism can be traced back to 19th-century utopian socialist thinkers and the Chartist movement in Great Britain, which somewhat differed in their goals but shared a common demand of democratic decision making and public ownership of the means of production, and viewed these as fundamental characteristics of the society they advocated for. Democratic socialism was also heavily influenced by the gradualist form of socialism promoted by the British Fabian Society and Eduard Bernstein's evolutionary socialism. In the 19th century, the ruling classes were afraid of socialism because it challenged their rule. Socialism has faced opposition since then, and the opposition to it has often been organized and violent. In countries such as Germany and Italy, democratic socialist parties were banned, like with Otto von Bismarck's Anti-Socialist Laws. With the expansion of liberal democracy and universal suffrage during the 20th century, democratic socialism became a mainstream movement which expanded across the world, as centre-left and left-wing parties came to govern, became the main opposition party, or simply a commonality of the democratic process in most of the Western world; one major exception was the United States. Democratic socialist parties greatly contributed to existing liberal democracy.
  • 8.3K
  • 22 Nov 2022
Topic Review
Literacy
Literacy is traditionally defined as the ability to read and write. In the modern world, this is one way of interpreting literacy. A more broad interpretation is literacy as knowledge and competence in a specific area. The concept of literacy has evolved in meaning. The modern term's meaning has been expanded to include the ability to use language, numbers, images, computers, and other basic means to understand, communicate, gain useful knowledge, solve mathematical problems and use the dominant symbol systems of a culture. The concept of literacy is expanding across OECD countries to include skills to access knowledge through technology and ability to assess complex contexts. A person who travels and resides in a foreign country but is unable to read or write in the language of the host country would also be regarded by the locals as illiterate. The key to literacy is reading development, a progression of skills that begins with the ability to understand spoken words and decode written words, and culminates in the deep understanding of text. Reading development involves a range of complex language underpinnings including awareness of speech sounds (phonology), spelling patterns (orthography), word meaning (semantics), grammar (syntax) and patterns of word formation (morphology), all of which provide a necessary platform for reading fluency and comprehension. Once these skills are acquired, the reader can attain full language literacy, which includes the abilities to apply to printed material critical analysis, inference and synthesis; to write with accuracy and coherence; and to use information and insights from text as the basis for informed decisions and creative thought. The inability to do so is called illiteracy or analphabetism. The United Nations Educational, Scientific and Cultural Organization (UNESCO) defines literacy as the "ability to identify, understand, interpret, create, communicate and compute, using printed and written materials associated with varying contexts. Literacy involves a continuum of learning in enabling individuals to achieve their goals, to develop their knowledge and potential, and to participate fully in their community and wider society".
  • 8.3K
  • 05 Dec 2022
Topic Review
Cultural Memory
Historic urban landscapes (HULs) are composed of layers of imbedded tangible and intangible features such as cultural memories. As the collective memories of city inhabitants, cultural memories can affect elements of social sustainability such as health, well-being, community identity, place perception and social engagement. This topic review points to the value of recalling cultural memory features in HULs, which can be used to achieve social sustainability.  In addition, it contributes to sustainable development through the contribution of cultural memory and its influence on the formation of place identity, sense of place, civic pride and quality of life in HULs. 
  • 8.3K
  • 27 Oct 2020
Topic Review
Bayraktar Tactical UAS
The Bayraktar Tactical UAS is a surveillance and reconnaissance unmanned aerial vehicle (UAV) initially developed for the Turkish Armed Forces. It is developed by the Kale-Baykar, a joint venture between the Kale Group and Baykar Technologies. In 2014, Bayraktar held the national endurance and altitude record for Turkey's unmanned aerial vehicles (UAV). It set a record for autonomous flight endurance when it flew 24 hours and 34 minutes at 18,000 feet on 5 August 2014. It furthermore recorded highest altitude of 27,030 feet on its flight on 14 June 2014 with full payload. Bayraktar TB2 successfully demonstrated firing of ROKETSAN MAM-L Smart Micro Munition with 100% accuracy in December 2015. While the Turkish Armed Forces describes Bayraktar as "Tactical UAV Class" to prevent it from being a competitor to the TAI Anka UAV, international standards would classify it as a medium-altitude long-endurance UAV. With its 650 kg MTOW and 12 meters wingspan platform powered by an internal combustion engine, Bayraktar is capable of flying at 22,500 feet and loitering for more than 24 hours.
  • 8.3K
  • 24 Oct 2022
Topic Review Peer Reviewed
OAM of Light: Origins and Applications
Orbital Angular Momentum (OAM) of light is generating growing interest within the scientific community. This entry reviews the origins and applications of OAM. It is the counterpart of linear momentum for systems in rotation. The general expression of OAM is discussed, followed by its implications in terms of phase distribution and donut-shaped intensity profiles. Applications described include the generation of optical torque, telecommunications enhancement, and the rotational Doppler effect, emphasizing the role and consequences of angular momentum. In particular, its use to manipulate systems or to detect rotations is described. Finally, further developments and technological barriers are considered.
  • 8.3K
  • 17 Sep 2025
Topic Review
Water-Gas Shift Reaction
The water-gas shift reaction (WGSR) describes the reaction of carbon monoxide and water vapor to form carbon dioxide and hydrogen: The water gas shift reaction was discovered by Italian physicist Felice Fontana in 1780. It was not until much later that the industrial value of this reaction was realized. Before the early 20th century, hydrogen was obtained by reacting steam under high pressure with iron to produce iron, iron oxide and hydrogen. With the development of industrial processes that required hydrogen, such as the Haber–Bosch ammonia synthesis, a less expensive and more efficient method of hydrogen production was needed. As a resolution to this problem, the WGSR was combined with the gasification of coal to produce a pure hydrogen product. As the idea of hydrogen economy gains popularity, the focus on hydrogen as a replacement fuel source for hydrocarbons is increasing.
  • 8.3K
  • 22 Nov 2022
Topic Review
Land Suitability Assessment
Land suitability assessment is a method of land evaluation, which identifies the major limiting factors for planting a particular crop. Land suitability assessment includes qualitative and quantitative evaluation. In the qualitative land suitability evaluations, information about climate, hydrology, topography, vegetation, and soil properties is considered and in quantitative assessment, the results are more detailed and yield is estimated. At present study we prepared land suitability assessment map for rain-fed wheat and barley crops based on FAO "land suitability assessment framework" using parametric method and machine learning algorithms in Kurdistan Province, located in west of Iran. This is a unique study that compared two machine learning-based and traditional-based approaches for mapping current and potential future land suitability classes. Moreover, potential yield of rain-fed wheat and barley crop were computed by FAO model.
  • 8.3K
  • 30 Oct 2020
Topic Review
Glossolalia
Glossolalia or speaking in tongues is a phenomenon in which people speak words that are apparently in languages unknown to the speaker. One definition used by linguists is the fluid vocalizing of speech-like syllables that lack any readily comprehended meaning, in some cases as part of religious practice in which it is believed to be a divine language unknown to the speaker. Glossolalia is practiced in Pentecostal and charismatic Christianity as well as in other religions. Sometimes a distinction is made between "glossolalia" and "xenolalia" or "xenoglossy", which specifically designates when the language being spoken is a natural language previously unknown to the speaker. This distinction is not universally made, and the New Testament of the Bible mentions the phenomenon in at least one passage in reference to speaking in languages known to others but not to the speakers.
  • 8.3K
  • 01 Dec 2022
Topic Review
Theories of International Trade
Economists have developed theories explaining World Trade, which are called” theories of international trade”. Theories of international trade explain what exactly happens in international trade, such as mercantilist theory. This theory was popular in the sixteenth and eighteenth centuries. During that time, a nation’s wealth consisted only of gold or other types of precious metals, so theorists suggested that nations begin to accumulate more and more gold and other types of metals. 
  • 8.3K
  • 08 Jul 2022
Topic Review
Carbon Emission Efficiency
Carbon emission efficiency is an important concept in environmental science; it refers to the economic benefits generated by production activities that produce carbon emissions at the same time. The less carbon emissions generated per unit of economic output, the more carbon emission efficient it is.
  • 8.3K
  • 26 May 2022
Topic Review
Consanguinity
Consanguinity ("blood relation", from Latin consanguinitas) is the property of being from the same kinship as another person. In that aspect, consanguinity is the quality of being descended from the same ancestor as another person. The laws of many jurisdictions set out the degree of consanguinity in relation to prohibited sexual relations and marriage parties. Such rules are also used to determine heirs of an estate according to statutes that govern intestate succession, which vary from jurisdiction to jurisdiction. In some places and times, cousin marriage is approved and expected; in others, it is taboo as incest. The degree of relative consanguinity can be illustrated with a consanguinity table in which each level of lineal consanguinity (generation or meiosis) appears as a row, and individuals with a collaterally consanguineous relationship share the same row. The Knot System is a numerical notation that defines consanguinity.
  • 8.3K
  • 28 Sep 2022
Topic Review
Design of Block Shear Failure
The block shear failure was reported firstly in 1978 for joints with not optimal geometry from an internal forces point of view. The test results proved the potential failure mode of tearing out in the web of the beam. Several studies concerning block shear failure were published in the last twenty years predicting the block shear capacity as a combination of fracture on the tension and shear plane. Block shear rupture is the potential failure mode for gusset plates, fin plates, coped beams, single/double angles and tee connections, where significant tension/shear forces are present. 
  • 8.3K
  • 21 Jul 2021
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