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Topic Review
Platinum Group Minerals
Russia and South Africa are the world’s leading producers of platinum group elements (PGEs). This places them in a unique position regarding the supply of these two key industrial commodities. The purpose of this paper is to provide a comparative high-level overview of aspects of the geological occurrence, mineralogy, and processing by flotation of the platinum group minerals (PGMs) found in each country. A summary of some of the major challenges faced in each country in terms of the concentration of the ores by flotation is presented alongside the opportunities that exist to increase the production of the respective metals. These include the more efficient recovery of minerals such as arsenides and tellurides, the management of siliceous gangue and chromite in the processing of these ores, and, especially in Russia, the development of novel processing routes to recover PGEs from relatively low grade ores occurring in dunites, black shale ores and in vanadium-iron-titanium-sulphide oxide formations.
  • 4.3K
  • 26 Jan 2021
Topic Review
Structure from Motion
Structure from Motion (SfM) is a photogrammetric range imaging technique for estimating three-dimensional structures from two-dimensional image sequences that may be coupled with local motion signals. It is studied in the fields of computer vision and visual perception. In biological vision, SfM refers to the phenomenon by which humans (and other living creatures) can recover 3D structure from the projected 2D (retinal) motion field of a moving object or scene.
  • 4.3K
  • 06 Oct 2022
Topic Review
Four Effects of High-Entropy Alloys
As a new type of alloy with high hardness, high heat resistance, strong corrosion resistance, high wear resistance and fatigue resistance, high-entropy alloys are different from any existing traditional alloy. As a new alloy system, high-entropy alloys have important research value and broad application prospects. Therefore, the design, preparation and application of high-entropy alloys have become an important direction for the development of new materials.
  • 4.3K
  • 17 Nov 2023
Topic Review
Sacred
Sacred describes something that is dedicated or set apart for the service or worship of a deity; is considered worthy of spiritual respect or devotion; or inspires awe or reverence among believers. The property is often ascribed to objects (a "sacred artifact" that is venerated and blessed), or places ("sacred ground"). French sociologist Émile Durkheim considered the dichotomy between the sacred and the profane to be the central characteristic of religion: "religion is a unified system of beliefs and practices relative to sacred things, that is to say, things set apart and forbidden.":47 In Durkheim's theory, the sacred represents the interests of the group, especially unity, which are embodied in sacred group symbols, or totems. The profane, on the other hand, involve mundane individual concerns.
  • 4.3K
  • 31 Oct 2022
Topic Review
Gendered Citizenship, Inequality, and Well-Being in Qatar
The impact of gendered citizenship on the well-being of cross-national families following the political blockade imposed on Qatar in 2017. More specifically, it examines how these families, women, and children face challenges related to their lives, well-being, and rights. Twenty-three face-to-face interviews were conducted with Qatari and non-Qatari women and men married to non-Qatari spouses residing in Qatar. 
  • 4.3K
  • 15 Jun 2022
Topic Review
Beam Steering Characteristics of Reconfigurable Transmitarray Antennas
The high gain beam steering antennas are widely used in 5G wireless mobile communications, radio frequency (RF) wireless power transmission, and satellite communications. In order to obtain high gain and beam steering characteristics, traditionally, antennas of the same type as phased array antennas, reflectarray antennas, and parabolic antennas have been designed. The transmitarray (TA) has attracted more and more interest from researchers due to its low profile, affordable cost, lower losses, low design complexity, and ease of fabrication. These have become popular solutions due to their remarkable applications, for instance, in biomedical systems (Brain and Breast Cancer Detection), civil and military radar systems, imaging systems, satellite communications, direct broadcasting services, and 6G/5G communication systems, etc.
  • 4.3K
  • 03 Mar 2022
Topic Review
Impact of Self-Driving Cars
The impact of self-driving cars is anticipated to be wide-ranging on many areas of daily life. Self-driving cars have been the subject of significant research on their environmental, practical, and lifesyle consequences. One significant predicted impact of self-driving cars is a substantial reduction in traffic collisions and resulting severe injuries or deaths. United States government estimates suggest 94% of traffic collisions are caused by human error, with a 2020 study estimating that making 90% of cars on US roads self-driving would save 25,000 lives per year. While this has significant benefits, other health downsides of self-driving cars are predicted; self-driving cars are suggested to worsen air pollution, noise pollution, and sedentary lifestyles, and may contribute to shortages of donor organs. Self-driving cars are anticipated to increase productivity and housing affordability, as well as reclaim land used for parking. However, they are also predicted to cause greater energy use, traffic congestion and sprawl. The impact of self-driving cars on absolute levels of individual car use is not yet clear, with commentators alternatively predicting increases and decreases. Self-driving cars are one of several potential autonomous vehicles, and other forms of self-driving vehicles, such as self-driving buses, may decrease car use and congestion in ways self-driving cars are unlikely to. The effect of self-driving cars on various employment fields is predicted to be wide-ranging. Impacts are anticipated on the healthcare, insurance, travel, and logistics fields. Auto insurance costs are expected to decrease, and the burden of cars on the healthcare system to reduce. Self-driving cars are predicted to have substantial and wide-ranging effects on transportation industries, with significant job losses in these fields.
  • 4.3K
  • 24 Nov 2022
Topic Review
Immigrant Paradox
The immigrant paradox is that recent immigrants often outperform more established immigrants and non-immigrants on a number of health-, education-, and conduct- or crime-related outcomes, despite the numerous barriers they face to successful social integration. According to the UN, the number of first-generation immigrants worldwide is 244 million. These large-scale population changes worldwide have led many scholars, across fields, to study the acculturation and adjustment of immigrants to their new homes. Specifically, researchers have examined immigrant experiences as they pertain to educational attainment, mental and physical health, and conduct/crime. Researchers have tried to understand why later generations seem to perform less well than their forebears. They have found that it can be explained by non-optimal methodology and differences in the way generations are modified by the host culture.
  • 4.3K
  • 29 Nov 2022
Topic Review
Ring Expansion and Ring Contraction
Ring expansion and ring contraction reactions in the course of organic synthesis refer to a set of reactions which can lead to the expansion or contraction of an existing ring. This often makes it possible to access structures that would be difficult if not impossible to synthesise with single cyclization reactions. Ring expansions are valuable because they allow access to larger systems that are difficult to synthesize through a single cyclization due to the slow rate of formation. Ring contractions are useful for making smaller, more strained rings from larger rings. Expansions are classified by the mechanism of expansion and the atom(s) added; contractions are characterized simply by the reactive intermediate which performs the contraction.
  • 4.3K
  • 01 Dec 2022
Topic Review
Personnel Psychology
Personnel Psychology is a subfield of Industrial and Organizational Psychology. Personnel psychology is the area of industrial/organizational psychology that primarily deals with the recruitment, selection and evaluation of personnel, and other job aspects such as morale, job satisfaction, and relationships between managers and workers in the workplace. It is the field of study that concentrates on the selection and evaluation of employees; this area of psychology deals with job analysis and defines and measures job performance, performance appraisal, employment testing, employment interviews, personnel selection and employee training, and human factors and ergonomics.
  • 4.3K
  • 02 Dec 2022
Topic Review
Greenwashing in Corporate Social Responsibility
Corporate social responsibility (CSR) has emerged as a pivotal area of focus, with an increasing number of companies prioritizing its integration into their operational strategies.
  • 4.3K
  • 20 Nov 2023
Topic Review
Blockchain
This entry provides an overview of the application of blockchain technologies for enabling traceability in the agri-food domain. It presents relevant definitions and the various types of blockchain solutions used in "farm to fork" traceability, including public vs private blockchain networks, consensus protocols and smart contracts.
  • 4.3K
  • 10 Jul 2020
Topic Review
Copper-Based Conductive Inks
Silver (Ag), gold (Au), and copper (Cu) have been utilized as metals for fabricating metal-based inks/pastes for printed/flexible electronics. Among them, Cu is the most promising candidate for metal-based inks/pastes. Cu has high intrinsic electrical/thermal conductivity, which is more cost-effective and abundant, as compared to Ag. Moreover, the migration tendency of Cu is less than that of Ag. Thus, recently, Cu-based inks/pastes have gained increasing attention as conductive inks/pastes for printed/flexible electronics. We can divide Cu-based inks/pastes into four categories from the viewpoints of Cu sources: (i) traditional micron-sized flake/powder type, (ii) nanoparticle type, (iii) nanowire type, and (iv) precursor ion type. However, the disadvantages of Cu-based inks/pastes are their instability against oxidation under an ambient condition and tendency to form insulating layers of Cu oxide, such as cuprous oxide (Cu2O) and cupric oxide (CuO). The formation of the Cu oxidation causes a low conductivity in sintered Cu films and interferes with the sintering of Cu particles. The surface and interface designs for Cu-based conductive inks/pastes are important strategies for the oxidation resistance of Cu and low-temperature sintering to produce highly conductive Cu patterns/electrodes on flexible substrates. The surface control approaches include surface designs by polymers, small ligands, core-shell structures, and surface activation. The Cu-based mixed inks/pastes offer improved performances compared with the single use of each component.
  • 4.3K
  • 07 Sep 2020
Topic Review
Nutritional Values of Dabai (Canarium odontophyllum)
Dabai (Canarium odontophyllum) is a fruit-bearing plant native to Borneo. Its fruit is an indigenous seasonal fruit that is considered to be underutilized due to its short shelf life.
  • 4.3K
  • 25 Nov 2022
Topic Review
Euronext
Euronext is a European stock exchange seated in Amsterdam, Brussels, London, Lisbon, Dublin and Paris. In addition to cash and derivatives markets, the Euronext group provides listing market data, market solutions, custody and settlement services. Its total product offering includes equities, exchange-traded funds, warrants and certificates, bonds, derivatives, commodities and indices as well as FX platform. In 2018, Euronext is the largest in continental Europe with 1,300 issuers representing a €3.8 trillion market capitalization. Euronext merged with NYSE Group, Inc. on April 4, 2007 to form NYSE Euronext (NYX). On November 13, 2013 Intercontinental Exchange (NYSE: ICE), completed acquisition of NYSE Euronext. In June 2014 Euronext completed an initial public offering making it a standalone company again.
  • 4.3K
  • 18 Oct 2022
Topic Review
Universe & Anharmonic Oscillator & Singularity Avoidance Higgs
The functioning of our universe and atomic is based on the oscillation of the particle itself and asymmetrically between matter and antimatter. This mechanism is a classical an-harmonic oscillator and uses a linear oscillation of the particle, where the energy can be represented by the graph of a potential well. In this potential well the alternation of energies ocurs between the kinetic energy and potential energy. This an-harmonic oscillation of the particle thus occurs through a gravitational oscillator (see "hole through the Earth simple harmonic motion"), followed by a singularity avoidance. Indeed the important kinetics of the particle leads to a singularity avoidance to pass over the supermassive black hole to plot the Higgs field/potential. The alternation of the particle at very high frequency generates by the principle of mass-energy equivalence in vacuum (E=mc²) a mass flux expressed by the quantum fluctuation determined by a scalar energy density. This scalar density represents for example the dark matter and the residues of the latter in the quantum vacuum. However a vectorial interpretation of the particle is possible as soon as its oscillation through the oscillator is really minimized before becoming a mass-energy equivalence flux. That represent the elements related to Einstein's Stress Energy Tensor. Here is the one of interpretation of quantum mechanics in relation to relativistic physics. 
  • 4.3K
  • 23 Aug 2022
Topic Review
Wage Growth
Wage growth (real wage growth) is a rise of wage adjusted for inflations, often expressed in percentage. In macroeconomics, wage growth is one of the main indications to measure economic growth for a long-term since it reflects the consumer's purchasing power in the economy as well as the level of living standards. An increase in wage growth implies price inflation in the economy while a low wage growth indicates deflation that needs artificial interferences such as through fiscal policies by federal/state government. Minimum wage law is often introduced to increase wage growth by stimulating price inflations from corresponding purchasing powers in the economy. Wage growth can also be maximised through the development of industry factors by investing skilled workers in which decision made by businesses. More financial compensation for skilled workers not only lifts wage growth but stimulates higher market prices in the economy. While a weak productivity influences a low wage growth, identified a long-term factor, a short-term problem for low wage growth is often identified as the spare capacity in the labour market. By the lower unemployment rate given by the more opportunities from the spare capacity in the labour market creates less competitiveness amongst the labours, which reduces wage growth. In order to achieve consistent strong wage growth and sustainable economic growth, high productivity is the key determinant. Higher labour productivity (measured by GDP per worker) stimulates price inflations in resulting in a rise in real wage growth. One of the major factors for the recent sluggish wage growth in advanced countries is caused by their lower labour productivities.
  • 4.3K
  • 17 Nov 2022
Topic Review
Right Triangle
A right triangle (American English) or right-angled triangle (British English) is a triangle in which one angle is a right angle (that is, a 90-degree angle). The relation between the sides and angles of a right triangle is the basis for trigonometry. The side opposite the right angle is called the hypotenuse (side c in the figure). The sides adjacent to the right angle are called legs (or catheti, singular: cathetus). Side a may be identified as the side adjacent to angle B and opposed to (or opposite) angle A, while side b is the side adjacent to angle A and opposed to angle B. If the lengths of all three sides of a right triangle are integers, the triangle is said to be a Pythagorean triangle and its side lengths are collectively known as a Pythagorean triple.
  • 4.3K
  • 17 Oct 2022
Topic Review
White Hole
White holes are regions of space-time that although matter may come out, no matter is able to enter; or in other words, they have gravitational features opposite to those of black holes. White holes exist in the solutions to Einstein's general theory of relativity and the maximal extension of the Schwarzschild metric. The term "white hole" was coined by Soviet cosmologist Igor Novikov in 1965 after his theorization on the existence.
  • 4.3K
  • 15 Oct 2023
Topic Review
International Roughness Index
The International Roughness Index (IRI) is the roughness index most commonly obtained from measured longitudinal road profiles. It is calculated using a quarter-car vehicle math model, whose response is accumulated to yield a roughness index with units of slope (in/mi, m/km, etc.). This performance measure has less stochasticity and subjectivity in comparison to other pavement performance indicators, but it is not completely devoid of randomness. The sources of variability in IRI data include the difference among the readings of different runs of the test vehicle and the difference between the readings of the right and left wheel paths. Despite these facts, since its introduction in 1986, the IRI has become the road roughness index most commonly used worldwide for evaluating and managing road systems. The measurement of IRI is required for data provided to the United States Federal Highway Administration, and is covered in several standards from ASTM International: ASTM E1926 - 08, ASTM E1364 - 95(2005), and others. IRI is also used to evaluate new pavement construction, to determine penalties or bonus payments based on smoothness.
  • 4.3K
  • 31 Oct 2022
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