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Topic Review
Hydrogen as an Alternative Fuel
Hydrogen is a very important fuel of our secure and clean energy future. Hydrogen will be the fuel of the future and gradually it will replace all current fossil fuels. Hydrogen can be used as a fuel for vehicles, to heat homes and offices, to produce electricity, and to fuel ships and aircraft. The present work provides an overview of hydrogen as an alternative fuel, which can be used in internal combustion engines and in fuel cells.
  • 14.1K
  • 27 Oct 2020
Topic Review
Armenia
Armenia, officially the Republic of Armenia, is a landlocked country in the Armenian Highlands of Eastern Europe. Due to its location in the South Caucasus, Armenia is sometimes described as transcontinental, spanning both Eastern Europe and Western Asia. It is bordered by Turkey to the west, Georgia to the north, the Lachin corridor (under a Russian peacekeeping force) and Azerbaijan to the east, and Iran and the Azerbaijani exclave of Nakhchivan to the south. Yerevan is the capital and largest city. Armenia is a unitary, multi-party, democratic nation-state with an ancient cultural heritage. The first Armenian state of Urartu was established in 860 BC, and by the 6th century BC it was replaced by the Satrapy of Armenia. The Kingdom of Armenia reached its height under Tigranes the Great in the 1st century BC and in the year 301 became the first state in the world to adopt Christianity as its official religion, The ancient Armenian kingdom was split between the Byzantine and Sasanian Empires around the early 5th century. Under the Bagratuni dynasty, the Bagratid Kingdom of Armenia was restored in the 9th century. Declining due to the wars against the Byzantines, the kingdom fell in 1045 and Armenia was soon after invaded by the Seljuk Turks. An Armenian principality and later a kingdom Cilician Armenia was located on the coast of the Mediterranean Sea between the 11th and 14th centuries. Between the 16th and 19th centuries, the traditional Armenian homeland composed of Eastern Armenia and Western Armenia came under the rule of the Ottoman and Persian empires, repeatedly ruled by either of the two over the centuries. By the 19th century, Eastern Armenia had been conquered by the Russian Empire, while most of the western parts of the traditional Armenian homeland remained under Ottoman rule. During World War I, 1.5 million Armenians living in their ancestral lands in the Ottoman Empire were systematically exterminated in the Armenian genocide. In 1918, following the Russian Revolution, all non-Russian countries declared their independence after the Russian Empire ceased to exist, leading to the establishment of the First Republic of Armenia. By 1920, the state was incorporated into the Transcaucasian Socialist Federative Soviet Republic, and in 1922 became a founding member of the Soviet Union. In 1936, the Transcaucasian state was dissolved, transforming its constituent states, including the Armenian Soviet Socialist Republic, into full Union republics. The modern Republic of Armenia became independent in 1991 during the dissolution of the Soviet Union. Armenia is a developing country and ranks 81st on the Human Development Index (2018). Its economy is primarily based on industrial output and mineral extraction. While Armenia is geographically located in the South Caucasus, it is generally considered geopolitically European. Since Armenia aligns itself in many respects geopolitically with Europe, the country is a member of numerous European organizations including the Council of Europe, the Eastern Partnership, Eurocontrol, the Assembly of European Regions, and the European Bank for Reconstruction and Development. Armenia is also a member of certain regional groups throughout Eurasia, including the Asian Development Bank, the Collective Security Treaty Organization, the Eurasian Union, and the Eurasian Development Bank. Armenia supports the de facto independent Artsakh, which was proclaimed in 1991. Armenia also recognises the Armenian Apostolic Church, the world's oldest national church, as the country's primary religious establishment. The unique Armenian alphabet was created by Mesrop Mashtots in 405 AD.
  • 14.1K
  • 10 May 2023
Biography
Kadir Mısıroğlu
Türk Bilgesi Kadir Mısıroğlu (𐱅𐰇𐰼𐰜:𐰋𐰃𐰠𐰏𐰾𐰃:𐰴𐰑𐰼:𐰢𐰃𐰽𐰺𐰆𐰍𐰞𐰆) (24 January 1933 – 5 May 2019) was a Turkish historian, lawyer, writer, and publisher.[1][2][3] [4][5] His character is integrated with the fez. Radical Islamist and Ottomanist. He is known for his outspoken stance against Mustafa Kemal's reforms and Kemalism.[6][7] Ka
  • 14.1K
  • 23 May 2024
Biography
Jean Piaget
Jean Piaget (UK: /piˈæʒeɪ/, US: /ˌpiːəˈʒeɪ/;[1] French: [ʒɑ̃ pjaʒɛ]; 9 August 1896 – 16 September 1980) was a Switzerland psychologist known for his work on child development. Piaget's theory of cognitive development and epistemological view are together called "genetic epistemology". Piaget placed great importance on the education of children. As the Director of the Internati
  • 14.0K
  • 21 Nov 2022
Topic Review
Germplasm Conservation
Germplasm is a valuable natural resource that provides knowledge about the genetic composition of a species and is crucial for conserving plant diversity. Germplasm protection strategies not only involve rescuing plant species threatened with extinction, but also help preserve all essential plants, on which rests the survival of all organisms. The successful use of genetic resources necessitates their diligent collection, storage, analysis, documentation, and exchange. Slow growth cultures, cryopreservation, pollen and DNA banks, botanical gardens, genetic reserves, and farmers’ fields are a few germplasm conservation techniques being employed. However, the adoption of in-vitro techniques with any chance of genetic instability could lead to the destruction of the entire substance, but the improved understanding of basic regeneration biology would, in turn, undoubtedly increase the capacity to regenerate new plants, thus expanding selection possibilities. Germplasm conservation seeks to conserve endangered and vulnerable plant species worldwide for future proliferation and development; it is also the bedrock of agricultural production. 
  • 14.0K
  • 25 Jun 2021
Topic Review
Straight-Six Engine
The straight-six engine (also referred to as an inline-six engine; abbreviated I6 or L6) is an internal combustion engine, with six cylinders mounted in a straight line along the crankcase with all the pistons driving a common crankshaft (straight engine). The bank of cylinders may be oriented at any angle, and where the bank is inclined away from the vertical, the engine is sometimes called a slant-six (although this is also a Chrysler-specific design). The straight-six layout is the simplest engine layout that possesses both primary and secondary mechanical engine balance, resulting in much less vibration than engines with fewer cylinders.
  • 14.0K
  • 15 Nov 2022
Topic Review
Drainpipe Materials through the Centuries
Agricultural drainage plays an important role worldwide in food production and conservation of soil resources, while safeguarding investments in agricultural production and irrigation projects. It can improve crop yields and land productivity, especially on poorly drained soils and in cases of prolonged waterlogging. Both the subsurface drainage materials and the installation techniques used have a long history dating to prehistoric times. Over time, new subsurface drainage materials, installation techniques and modernized equipment developed continuously to take advantage of technological advances provided through research and development, while the planning and organization of the implementation process improved.
  • 14.0K
  • 27 Oct 2020
Topic Review
Solar Symbol
A solar symbol is a symbol representing the Sun. Common solar symbols include circles (with or without rays), crosses, and spirals. In religious iconography, personifications of the Sun or solar attributes are often indicated by means of a halo or a radiate crown. When the systematic study of comparative mythology first became popular in the 19th century, scholarly opinion tended to over-interpret historical myths and iconography in terms of "solar symbolism". This was especially the case with Max Müller and his followers beginning in the 1860s in the context of Indo-European studies. Many "solar symbols" claimed in the 19th century, such as the swastika, triskele, Sun cross, etc. have tended to be interpreted more conservatively in scholarship since the later 20th century.
  • 14.0K
  • 25 Oct 2022
Topic Review
State-Dependent Memory
State-dependent memory or state-dependent learning is the phenomenon through which memory retrieval is most efficient when an individual is in the same state of consciousness as they were when the memory was formed. The term is often used to describe memory retrieval while in states of consciousness produced by psychoactive drugs – most commonly, alcohol, but has implications for mood or non-substance induced states of consciousness as well. Unlike context-dependent memory, which involves an individual's external environment and conditions, state-dependent memory applies to the individual's internal conditions. For example, while context-dependent memory might refer to the idea that taking a test in the same room that an individual studied in will make it easier to retrieve those memories, state-dependent learning refers to the idea that if an individual always studied for a test while slightly caffeinated, it will most likely be easiest to recall what they studied during the test if they are at a similar level of caffeination.
  • 14.0K
  • 24 Oct 2022
Topic Review
Misogyny in Horror Films
Misogyny can occur in horror films when there is a degrading representation of women. This is found particularly in slasher films, where there is often gendered specific violence towards women. Female characters experience violence and brutality at the hands of male antagonists far more often than male characters in these films. Female characters are likely to experience sexual violence, particularly in the rape-and-revenge subgenre.
  • 13.9K
  • 28 Nov 2022
Topic Review
Flood Prediction Using ML Models
Floods are among the most destructive natural disasters, which are highly complex to model. The research on the advancement of flood prediction models contributed to risk reduction, policy suggestion, minimization of the loss of human life, and reduction of the property damage associated with floods. To mimic the complex mathematical expressions of physical processes of floods, during the past two decades, machine learning (ML) methods contributed highly in the advancement of prediction systems providing better performance and cost-effective solutions. Due to the vast benefits and potential of ML, its popularity dramatically increased among hydrologists.Researchers through introducing novel ML methods and hybridizing of the existing ones aim at discovering more accurate and efficient prediction models. The main contribution of this paper is to demonstrate the state of the art of ML models in flood prediction and to give insight into the most suitable models. In this paper, the literature where ML models were benchmarked through a qualitative analysis of robustness, accuracy, effectiveness, and speed are particularly investigated to provide an extensive overview on the various ML algorithms used in the field. The performance comparison of ML models presents an in-depth understanding of the different techniques within the framework of a comprehensive evaluation and discussion. As a result, this paper introduces the most promising prediction methods for both long-term and short-term floods. Furthermore, the major trends in improving the quality of flood prediction models are investigated. Among them, hybridization, data decomposition, algorithm ensemble, and model optimization are reported as the most effective strategies for the improvement of ML methods. This survey can be used as a guideline for hydrologists as well as climate scientists in choosing the proper ML method according to the prediction task.
  • 13.9K
  • 04 Jan 2023
Topic Review
Agricultural Production in Qatar
Starting in the 1970s, Qatar had almost entirely based its economic growth on resource exploitation of the hydrocarbon sector, with agriculture being considered only as a ‘’hobby’’, rather than an important economic activity. The real driver of change affecting Qatar’s agricultural sector is the issue of food security, after the 2017 embargo (imposed by neighboring countries that made Qatar’s government critically aware that it cannot rely on other countries to secure its food basket), and thus highlighted the need to produce in the country.The factor that has most hindered the development of productive agricultural and horticultural systems in the past has been the availability of land, with suitable soils. This is a consequence of Qatar’s harsh climate; it is in a hot arid zone characterized by sparse precipitation; high summer temperatures; together with high humidity in the late summer months that makes working outside very difficult; very high solar radiation; strong winds; and limited freshwater availability for irrigation causing dependency on desalinated abstracted groundwater, and/or (more recently) on desalinated sea-water.
  • 13.9K
  • 24 Apr 2021
Topic Review
New Seismotectonic Atlas of Greece
Integration and harmonization of the most recent seismological, geological, tectonic, geophysical and geodetic datasets, with the aim of capturing the potential of ground deformation towards a more reliable evaluation of seismic risk at a national level.
  • 13.9K
  • 20 Nov 2020
Topic Review
Guava Leaves
Psidium guajava (L.) belongs to the Myrtaceae family and it is an important fruit in tropical areas like India, Indonesia, Pakistan, Bangladesh, and South America. The leaves of the guava plant have been studied for their health benefits which are attributed to their plethora of phytochemicals, such as quercetin, avicularin, apigenin, guaijaverin, kaempferol, hyperin, myricetin, gallic acid, catechin, epicatechin, chlorogenic acid, epigallocatechin gallate, and caffeic acid. Extracts from guava leaves (GLs) have been studied for their biological activities, including anticancer, antidiabetic, antioxidant, antidiarrheal, antimicrobial, lipid-lowering, and hepatoprotection activities.
  • 13.9K
  • 14 Apr 2021
Topic Review
Water Quality Index
A critical water quality index (WQI) method has been used to determine the overall water quality status of surface water and groundwater systems globally since the 1960s. WQI follows four steps: parameter selection, sub-indices, establishing weights, and final index aggregation.
  • 13.9K
  • 09 Apr 2021
Topic Review
Physical Properties of Food Materials
The physical properties of food materials have defined those properties that can only be measured by physical means rather than chemical means. Food materials are basically naturally occurring biological-originated raw materials that have their own exclusive physical identity that makes them unique in nature. Due to the uniqueness of their physical properties, to properly measure the different physical characteristics of any food materials to get control and understand about the changes in their native physical characteristics with the influence of time-temperature-processing-treatment-exposure, proper measurement techniques for various physical properties of food materials are required with numerous desired outputs.
  • 13.8K
  • 25 Feb 2022
Topic Review
GAZ Tigr
The GAZ Tigr (Russian: Тигр and English: Tiger) is a Russia n 4x4, multipurpose, all-terrain infantry mobility vehicle manufactured by GAZ, first delivered to the Russian Army in 2006. Primarily used by the Russian Federation's armed forces, it is also used by numerous other countries.
  • 13.8K
  • 26 Oct 2022
Topic Review
Burnout and Personal Accomplishment
Research on burnout has traditionally focused on job demands, with less attention paid to protective factors. From the emerging and innovative area of psychology of sustainability and sustainable development, the relationship that job demands (workload), and personal resources (psychological capital) have with burnout was analyzed. Results show that (1) psychological capital and workload are related to burnout, and (2) personal accomplishment is more a personal resource than burnout dimension. The results confirm the role of psychological capital as a protective factor for burnout.
  • 13.8K
  • 27 Oct 2020
Topic Review
Magellan's Circumnavigation
In 1519, the Portuguese naval officer and explorer Ferdinand Magellan led a Spanish expedition to find a western route to the East Indies and reach the Moluccas or Spice Islands (in present day Indonesia) with a fleet known as the Armada de Molucca. After the death of Magellan in the Philippines in 1521 and following several other short-lived leaderships, Spanish navigator Juan Sebastián Elcano led the expedition to the Spice Islands and ultimately across the Indian Ocean and up the Atlantic ocean back to Spain, resulting in the first circumnavigation of the world in 1522. The expedition is therefore also known as the Magellan–Elcano circumnavigation. The goal of the expedition was to find a western route to the Moluccas (Spice Islands) and trade for spices. Magellan left Spain on 20 September 1519, sailed across the Atlantic, and discovered the strait that now bears his name, allowing him to pass through the southern tip of South America into the Pacific Ocean (which he named). The fleet performed the first ever crossing of the Pacific, stopping in what is today called the Philippines , and eventually reached the Moluccas, accomplishing its goal. A much-depleted crew finally returned to Spain on 6 September 1522. The fleet initially consisted of about 270 men and five ships: four carracks and one caravel. The expedition faced numerous hardships including mutinies, starvation, scurvy, storms, and hostile encounters with indigenous people. Magellan died in battle in the Philippine islands and was succeeded as captain-general by a series of officers, with Juan Sebastián Elcano leading the trip onward to Spain. He and seventeen other men in one ship (the Victoria) were the only ones to circumnavigate the globe. The expedition was funded mostly by King Charles I of Spain, with the hope that it would discover a profitable western route to the Moluccas, as the eastern route was controlled by Portugal under the Treaty of Tordesillas. Though the expedition did find a route, it was much longer and more arduous than expected, and was therefore not commercially useful. Nevertheless, the first circumnavigation has been regarded as a great achievement in seamanship, and had a significant impact on the European understanding of the world.
  • 13.8K
  • 16 Nov 2022
Topic Review
Voltaire
François-Marie Arouet (French: [fʁɑ̃swa maʁi aʁwɛ]; 21 November 1694 – 30 May 1778), known by his nom de plume Voltaire (/vɒlˈtɛər, voʊl-/; also US: /vɔːl-/, French: [vɔltɛːʁ]), was a French Enlightenment writer, historian, and philosopher famous for his wit, his criticism of Christianity—especially the Roman Catholic Church—as well as his advocacy of freedom of speech, freedom of religion, and separation of church and state. Voltaire was a versatile and prolific writer, producing works in almost every literary form, including plays, poems, novels, essays, histories, and scientific expositions. He wrote more than 20,000 letters and 2,000 books and pamphlets. He was an outspoken advocate of civil liberties, and was at constant risk from the strict censorship laws of the Catholic French monarchy. His polemics witheringly satirized intolerance, religious dogma, and the French institutions of his day.
  • 13.8K
  • 17 Oct 2022
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