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Topic Review
African Humid Period
The African humid period (AHP) is a climate period in Africa during the late Pleistocene and Holocene geologic epochs, when northern Africa was wetter than today. The covering of much of the Sahara desert by grasses, trees and lakes was caused by changes in Earth's orbit around the Sun; changes in vegetation and dust in the Sahara which strengthened the African monsoon; and increased greenhouse gases, which may, or may not imply that anthropogenic global warming could result in a shrinkage of the Sahara desert. During the preceding last glacial maximum, the Sahara contained extensive dune fields and was mostly uninhabited. It was much larger than today, but its lakes and rivers such as Lake Victoria and the White Nile were either dry or at low levels. The humid period began about 14,600–14,500 years ago at the end of Heinrich event 1, simultaneously to the Bølling-Allerød warming. Rivers and lakes such as Lake Chad formed or expanded, glaciers grew on Mount Kilimanjaro and the Sahara retreated. Two major dry fluctuations occurred; during the Younger Dryas and the short 8.2 kiloyear event. The African humid period ended 6,000–5,000 years ago during the Piora Oscillation cold period. While some evidence points to an end 5,500 years ago, in the Sahel, Arabia and East Africa the period appears to have taken place in several steps such as the 4.2 kiloyear event. The AHP led to a widespread settlement of the Sahara and the Arabian Deserts, and had a profound effect on African cultures, such as the birth of the Pharaonic civilization. They lived as hunter-gatherers until the agricultural revolution and domesticated cattle, goats and sheep. They left archeological sites and artifacts such as one of the oldest ships in the world, and rock paintings such as those in the Cave of Swimmers and in the Acacus Mountains. Earlier humid periods in Africa were postulated after the discovery of these rock paintings in now-inhospitable parts of the Sahara. When the period ended, humans gradually abandoned the desert in favour of regions with more secure water supplies, such as the Nile Valley and Mesopotamia, where they gave rise to early complex societies.
  • 13.1K
  • 10 Nov 2022
Topic Review
Vehicular Ad Hoc Networks
The vehicular ad hoc network is an emerging area of technology that provides intelligent transportation systems with vast advantages and applications. Frequent disconnections between the vehicular nodes due to high-velocity vehicles impact network performance. 
  • 13.1K
  • 27 Sep 2022
Topic Review
Phanerozoic
The Phanerozoic Eon is the current geologic eon in the geologic time scale, and the one during which abundant animal and plant life has existed. It covers 541 million years to the present and began with the Cambrian Period when animals first developed hard shells preserved in the fossil record. The time before the Phanerozoic, called the Precambrian, is now divided into the Hadean, Archaean and Proterozoic eons. The time span of the Phanerozoic starts with the sudden appearance of fossilized evidence of a number of animal phyla; the evolution of those phyla into diverse forms; the emergence and development of complex plants; the evolution of fish; the emergence of insects and tetrapods; and the development of modern fauna. Plant life on land appeared in the early Phanerozoic eon. During this time span, tectonic forces caused the continents to move and eventually collect into a single landmass known as Pangaea (the most recent supercontinent), which then separated into the current continental landmasses.
  • 13.0K
  • 08 Oct 2022
Topic Review
Meanings of Minor Planet Names: 1–1000
As minor planet discoveries are confirmed, they are given a permanent number by the IAU's Minor Planet Center (MPC), and the discoverers can then submit names for them, following the IAU's naming conventions. The list below concerns those minor planets in the specified number-range that have received names, and explains the meanings of those names. Official naming citations of newly named small Solar System bodies are published in MPC's Minor Planet Circulars several times a year. Recent citations can also be found on the JPL Small-Body Database (SBDB). Until his death in 2016, German astronomer Lutz D. Schmadel compiled these citations into the Dictionary of Minor Planet Names (DMP) and regularly updated the collection. Based on Paul Herget's The Names of the Minor Planets, Schmadel also researched the unclear origin of numerous asteroids, most of which had been named prior to World War II.  This article incorporates public domain material from the United States Government document "SBDB". New namings may only be added after official publication as the preannouncement of names is condemned by the Committee on Small Body Nomenclature.
  • 13.0K
  • 25 Oct 2022
Topic Review
Honda Civic Hybrid
The Honda Civic Hybrid is a variation of the Honda Civic with a hybrid electric powertrain. Honda introduced the Civic Hybrid in Japan in December 2001 and discontinued it in 2015. In the United States, it was the first hybrid automobile to be certified as an Advanced Technology Partial Zero-Emissions Vehicle (AT-PZEV) from the California Air Resources Board (CARB). The Civic Hybrid uses an Integrated Motor Assist hybrid system similar to that of the Honda Insight. The Civic Hybrid was only marketed in sedan configurations.
  • 13.0K
  • 28 Nov 2022
Topic Review
Effect of COVID-19 Pandemic on the Fashion Industry
The preference for a specific fashion style proved to have an impact on the product, promotion, WOM and fashion lovers’ behavior during COVID-19. Moreover, those elements have an impact on the frequency of fashion apparel consumption. Based on these results, fashion companies can tailor their activities in line with the predominant style of their fashion apparel to improve their economic sustainability during the post-COVID-19 era. 
  • 13.0K
  • 06 May 2022
Topic Review
IKCO EF Engines
IKCO EF engines are a family of four-cylinder engines. The EF7 series are designed jointly by Iran Khodro Powertrain Company (IPCO) and F.E.V GmbH of Germany. The other models will be designed by IPCO itself. IPCO is the powertrain designing & producing company of Iranian car manufacturer Iran Khodro (IKCO). IKCO aims to supply 800,000 powertrains by 2010. The first phase of IKCO EF Engines project (EF7 Dual-Fuel) investments were about 80 million US$. EF4 & EF7 engines use CNG as their main fuel and they can also use gasoline. EFD is the first engine of the EF family that is single-fuel. It uses high-quality diesel (Euro 4 Quality or better) as fuel. EF engines share most of their parts between them. It was IKCO's aim to reduce costs and provide ease of supplying the parts in the future for after-sales services. The EF family dual-fuel and petrol-fuel engines have achieved the Euro IV emission standard and are able to achieve Euro V emission standard with some minor changes but EFD will be the first engine of the family which comes with the Euro IV emission standard as its first release, and is able to achieve the Euro VI emission standard with some changes. The most important suppliers for EF engines are INA for sensitive VVT parts and some other mechanical parts, MAHLE which supplies some important parts of the engine family such as pistons, with Bosch supplying the ECU and electrically controlled pedal and lots of other important sensitive electronic parts. Almost all of the parts (except high-tech and sensitive parts) from worldwide well-known companies (as mentioned) are produced in Iran under license with the highest required quality for the engines. The Germany company Bosch had shown interest in assembling the Iranian engine under license. In 2008 IKCO has announced that EF7 is among the three best CNG-based engines of the world in designing.
  • 13.0K
  • 01 Dec 2022
Topic Review
Rotary-Percussion Drilling
The rotary-percussion drilling method is a prospective way to decrease drilling costs. It is obvious, based on literature analyses and finished geothermal drilling, that the Lublin Basin can be perceived as the one where rotary-percussion drilling can be used to drill an overburden of shale rocks. The paper explained the geology of the Lublin Basin, its’ geological structures, and the possibility of the use of drilling with a down-the-hole hammer, which could significantly decrease the cost of the whole shale gas drilling investment. Data collected from the wells drilled in the Lublin Basin were compared and analyzed to determine the viability of rotary-percussion drilling. Provided analyses showed that using the rotary-percussion drilling method in the Lublin Basin had a greater possibility of application than in other Polish shale basins (Baltic and Podlasie). 
  • 13.0K
  • 28 May 2021
Topic Review
Microstructure of Ni-Based Superalloy
To understand the behaviour of the especially complex Ni-based superalloys at high-homologous temperatures it is necessary to characterize their microstructure in fully heat-treatment condition. Detection and characterization of precipitates even nano-precipitates is essential in the study of creep and fatigue degradation. Without the knowledge about the phase composition of material, it is problematic to predict the microstructure evolution during long-term service. The main aim of this work was to perform the comprehensive characterization of equiaxed Ni-based superalloy René 108 from micro- to atomic-scale resolution by using analytical microscopy techniques.    
  • 13.0K
  • 20 Dec 2020
Topic Review
Physiological Effects of Marijuana
To understand the impact of marijuana on the cardiovascular system, it is imperative to understand the endocannabinoid system. The endocannabinoid system (ECS) is comprised of the endocannabinoids anandamide and 2-arachidonylglycerol (both of which are endogenous lipid mediators), their metabolic enzymes, and G-protein coupled cannabinoid receptor 1 (CB1R) plus G-protein coupled cannabinoid receptor 2 (CB2R) [24]. CB1R is the primary receptor that mediates the effects of marijuana. CB1R is present in the brain, heart, vascular smooth muscle, and peripheral nervous system [6]. Its extensive presence in the human body makes its activation wide-reaching and impacts multiple systems.
  • 12.9K
  • 06 Nov 2020
Topic Review
Natural Hazards in Pakistan
Natural hazards are dynamic and unpredictable events that are a continuous threat to global socio-economic development. Humans’ reactions to these catastrophes are influenced by their proximity to the hazards and their ability to anticipate, resist, cope with, and recover from their consequences. Due to climatic changes, the risk of multiple natural hazards is expected to increase in several regions of Pakistan.
  • 12.9K
  • 08 Feb 2023
Topic Review
Information and Communications Technology
Information and communications technology (ICT) is an extensional term for information technology (IT) that stresses the role of unified communications and the integration of telecommunications (telephone lines and wireless signals) and computers, as well as necessary enterprise software, middleware, storage and audiovisual, that enable users to access, store, transmit, understand and manipulate information. ICT is also used to refer to the convergence of audiovisuals and telephone networks with computer networks through a single cabling or link system. There are large economic incentives to merge the telephone networks with the computer network system using a single unified system of cabling, signal distribution, and management. ICT is an umbrella term that includes any communication device, encompassing radio, televiision, cell phones, computer and network hardware, satellite systems and so on, as well as the various services and appliances with them such as video conferencing and distance learning. ICT also includes analog technology, such as paper communication, and any mode that transmits communication. ICT is a broad subject and the concepts are evolving. It covers any product that will store, retrieve, manipulate, transmit, or receive information electronically in a digital form (e.g., personal computers including smartphones, digital television, email, or robots). Skills Framework for the Information Age is one of many models for describing and managing competencies for ICT professionals for the 21st century.
  • 12.9K
  • 27 Oct 2022
Topic Review
Working Principle of Hydraulic Control System
Hydraulic control systems are a feedback control system that uses hydraulic components as control and execution components, and hydraulic oil as the working medium for energy transmission. The movement of hydraulic actuators refers to the system output (including displacement, velocity, acceleration, and force), which is transmitted to the controller through feedback components. The input signal of the control component is adjusted according to the error size, so that the system output can automatically, quickly, and accurately track the system input instructions. Hydraulic control systems are classified into pump-controlled hydraulic control systems and valve-controlled hydraulic control systems based on their various control modes and valve components.
  • 12.9K
  • 18 Dec 2023
Topic Review
Multifactor Leadership Questionnaire
The Multifactor Leadership Questionnaire (MLQ) is a psychological inventory consisting of 36 items pertaining to leadership styles and 9 items pertaining to leadership outcomes. The MLQ was constructed by Bruce J. Avolio and Bernard M. Bass with the goal to assess a full range of leadership styles. The MLQ is composed of 9 scales that measure three leadership styles: transformational leadership (5 scales), transactional leadership (2 scales), and passive/avoidant behavior (2 scales), and 3 scales that measure outcomes of leadership. The MLQ takes an average of 15 minutes to complete and can be administered to an individual or group. The MLQ can be used to differentiate effective and ineffective leaders at all organizational levels and has been validated across many cultures and types of organizations. It is used for leadership development and research. The MLQ is designed as a multi-rater (or 360-degree) instrument, meaning that the leadership assessment considers the leader's self-assessment alongside the assessments of their leadership from their superiors, peers, subordinates, and others. The Leader (Self) Form and the Rater Form of the MLQ can be completed and assessed separately - however validity is much weaker when assessing leadership using only the Leader (Self) Form. Following the publication of the original MLQ in 1990, new versions of the MLQ were gradually developed to fit different assessment needs. The current versions of the MLQ are: Multifactor Leadership Questionnaire 360 (MLQ 360), Multifactor Leadership Questionnaire Self Form (MLQ Self), Multifactor Leadership Questionnaire Rater Form (MLQ Rater Form), Team Multifactor Leadership Questionnaire (TMLQ), and Multifactor Leadership Questionnaire Actual vs. Ought. All MLQ versions are protected by copyright law and published by Mind Garden, Inc. The MLQ underwent a re-branding for its scales in 2015 with the justification of replacing the heavily-academic scale names with terms that would be more widely and easily understood by those outside of academia, such as business leaders and consultants. Recent academic research using the MLQ continue to use the original scale names. The MLQ is often combined with the Authentic Leadership Questionnaire (ALQ) to assess the self-awareness, transparency, ethics/morality, and processing ability of leaders (the ALQ was constructed by Avolio with William L. Gardner and Fred O. Walumbwa in 2007).
  • 12.9K
  • 20 Oct 2022
Topic Review
Club of Rome
Founded in 1968 at Accademia dei Lincei in Rome, Italy, the Club of Rome consists of current and former heads of state, UN bureaucrats, high-level politicians and government officials, diplomats, scientists, economists, and business leaders from around the globe. It stimulated considerable public attention in 1972 with the first report to the Club of Rome, The Limits to Growth. Since 1 July 2008 the organization has been based in Winterthur, Switzerland.
  • 12.9K
  • 02 Nov 2022
Topic Review
Transition from Industry 4.0 to Society 5.0
In the era of Industry 4.0, manufacturing and production systems were revolutionized by increasing operational efficiency and developing and implementing new business models, services, and products. Several countries have begun orchestrating initiatives towards the design and development of the human-centric aspect of technologies, systems, and services, which has been coined as Industry 5.0. The impact of Industry 5.0 will extend to societal transformation, which eventually leads to the generation of a new society, the Society 5.0.
  • 12.9K
  • 07 Sep 2022
Topic Review
Shallow Affect
Reduced affect display, sometimes referred to as emotional blunting, is a condition of reduced emotional reactivity in an individual. It manifests as a failure to express feelings (affect display) either verbally or nonverbally, especially when talking about issues that would normally be expected to engage the emotions. Expressive gestures are rare and there is little animation in facial expression or vocal inflection. Reduced affect can be symptomatic of autism, schizophrenia, depression, posttraumatic stress disorder, depersonalization disorder, schizoid personality disorder or brain damage. It may also be a side effect of certain medications (e.g., antipsychotics and antidepressants). Reduced affect should be distinguished from apathy and anhedonia, which explicitly refer to a lack of emotion, whereas reduced affect is a lack of emotional expression (affect display) regardless of whether emotion (underlying affect) is actually reduced or not.
  • 12.9K
  • 24 Oct 2022
Topic Review
Battery Management System Subsystems and Their Influence
As the battery provides the entire propulsion power in electric vehicles (EVs), the utmost importance should be ascribed to the battery management system (BMS) which controls all the activities associated with the battery. 
  • 12.9K
  • 28 Jun 2022
Topic Review
Types of Adsorbents
There are two types of adsorbents, namely, natural and synthetic adsorbents. Several examples of natural adsorbents include clay and zeolite (abundant and cheap). On the other hand, researchers can produce synthetic adsorbents (activated carbon) via agricultural waste, industrial waste, and household waste.
  • 12.9K
  • 27 Oct 2022
Topic Review
Applications of Carbon Fiber-Reinforced Polymer Composites
Carbon fiber-reinforced polymer (CFRP) composites are used in a variety of applications such as aircraft, automobiles, body armors, and the sports sector owing to their ultra-strong and lightweight characteristics.
  • 12.8K
  • 10 Jun 2022
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