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Topic Review
Determinants of NRLAIS in Ethiopia
Ethiopia has embarked on one of the largest digitalization programs for rural land registration in Africa. The program is called the national rural land administration information system (NRLAIS). NRLAIS utilizes a modular technology stack with web-based approach and Land Administration Domain Model (LADM) for rural land registration. NRLAIS considered the functional and legal requirements at four government organizational structures (federal, regional, zonal, and woreda).
  • 4.2K
  • 23 Dec 2021
Topic Review
Effects of Chemical Fertilizer Combined with Organic Fertilizer
Chemical fertilizer has been excessively used for high yield of citrus around the world, especially in China; meanwhile, it deteriorates the citrus orchard soil environment. To resolve the conflict, the use of organic fertilizer provides a promising solution. This entry is to evaluate the effect of organic fertilizer on citrus yield, growth, soil properties etc. when nutrients of fertilizer of each treatment were equal except CK. 
  • 4.2K
  • 22 Mar 2022
Topic Review
State of Nature
The state of nature, in moral and political philosophy, religion, social contract theories and international law, is the hypothetical life of people before societies came into existence. Philosophers of the state of nature theory deduce that there must have been a time before organized societies existed, and this presumption thus raises questions such as: "What was life like before civil society?"; "How did government first emerge from such a starting position?," and; "What are the hypothetical reasons for entering a state of society by establishing a nation-state?". In some versions of social contract theory, there are no rights in the state of nature, only freedoms, and it is the contract that creates rights and obligations. In other versions the opposite occurs: the contract imposes restrictions upon individuals that curtail their natural rights. Societies existing before or without a political state are currently studied in such fields as paleolithic history, and the anthropological subfields of archaeology, cultural anthropology, social anthropology, and ethnology, which investigate the social and power-related structures of indigenous and uncontacted peoples living in tribal communities.
  • 4.2K
  • 11 Nov 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.
  • 4.2K
  • 03 Mar 2022
Topic Review
Relational Theory
In physics and philosophy, a relational theory (or relationism) is a framework to understand reality or a physical system in such a way that the positions and other properties of objects are only meaningful relative to other objects. In a relational spacetime theory, space does not exist unless there are objects in it; nor does time exist without events. The relational view proposes that space is contained in objects and that an object represents within itself relationships to other objects. Space can be defined through the relations among the objects that it contains considering their variations through time. The alternative spatial theory is an absolute theory in which the space exists independently of any objects that can be immersed in it. The relational point of view was advocated in physics by Gottfried Wilhelm Leibniz and Ernst Mach (in his Mach's principle). It was rejected by Isaac Newton in his successful description of classical physics. Although Albert Einstein was impressed by Mach's principle, he did not fully incorporate it into his general theory of relativity. Several attempts have been made to formulate a full Machian theory, but most physicists think that none have so far succeeded. For example, see Brans–Dicke theory. Relational quantum mechanics and a relational approach to quantum physics have been independently developed, in analogy with Einstein's special relativity of space and time. Relationist physicists such as John Baez and Carlo Rovelli have criticised the leading unified theory of gravity and quantum mechanics, string theory, as retaining absolute space. Some prefer a developing theory of gravity, loop quantum gravity for its 'backgroundlessness'. A recent synthesis of relational theory, called R-theory, continuing the work of the mathematical biologist Robert Rosen (who developed "relational biology" and "relational complexity" as theories of life) takes a position between the above views. Rosen's theory differed from other relational views in defining fundamental relations in nature (as opposed to merely epistemic relations we might discuss) as information transfers between natural systems and their organization (as expressed in models). R-theory extends the idea of organizational models to nature generally. As interpreted by R-theory, such "modeling relations" describe reality in terms of information relations (encoding and decoding) between measurable existence (expressed as material states and established by efficient behavior) and implicate organization or identity (expressed as formal potential and established by final exemplar), thus capturing all four of Aristotle's causalities within nature (Aristotle defined final cause as immanent from outside of nature). Applied to space-time physics, it claims that space-time is real but established only in relation to existing events, as a formal cause or model for the location of events relative to each other; and in reverse a system of space-time events establishes a template for space-time. R-theory is thus a form of model-dependent realism. It claims to more closely follow the views of Mach, Leibniz, Wheeler and Bohm, suggesting that natural law itself is system-dependent.
  • 4.2K
  • 21 Oct 2022
Topic Review
Censorship of Twitter
Censorship of Twitter refers to Internet censorship by governments that block access to Twitter. Twitter censorship also includes governmental notice and take down requests to Twitter, which Twitter enforces in accordance with its Terms of Service when a government or authority submits a valid removal request to Twitter indicating that specific content (such as a tweet) is illegal in their jurisdiction.
  • 4.2K
  • 11 Nov 2022
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.
  • 4.2K
  • 25 Nov 2022
Topic Review
Low Molecular Weight Chitosan
Chitosan is a biopolymer with high added value, and its properties are related to its molecular weight. Thus, high molecular weight values provide low solubility of chitosan, presenting limitations in its use. Based on this, several studies have developed different hydrolysis methods to reduce the molecular weight of chitosan.
  • 4.2K
  • 13 Aug 2021
Biography
Thomas Gold
Thomas Gold (also known as Tommy Gold),[1] (May 22, 1920 – June 22, 2004[2]) was an Austrian-born astrophysicist, a professor of astronomy at Cornell University, a member of the U.S. National Academy of Sciences, and a Fellow of the Royal Society (London).[2] Gold was one of three young Cambridge scientists who in 1948 proposed the now mostly abandoned "steady state" hypothesis of the universe
  • 4.2K
  • 14 Nov 2022
Topic Review
Infrared Spectroscopy in Biological Studies
Infrared (IR) radiation is electromagnetic radiation with wavenumbers ranges of 12,500–10 cm−1. The IR region in the electromagnetic spectrum can be subdivided into three spectral regions, namely near-IR (NIR, 12,500–4000 cm−1), mid-IR (MIR, 4,000–400 cm−1), and far-IR (FIR, 400–10 cm−1). Accumulating evidence has shown that IR radiation has been widely investigated for biological studies and effects. The interaction between IR radiation and biomolecules enables to study the specific molecular vibrations of the sample constituents. IR spectroscopy, specifically MIR, has been used to investigate large numbers of biological samples such as cells, tissues, organ, and biofluids, providing qualitative and quantitative information that could be used for detection and classification. Notably, FTIR spectroscopy is considered a promising tool to study and analyze biological samples using MIR radiation. 
  • 4.2K
  • 09 Jan 2023
Topic Review
Mineral Characterization Using Scanning Electron Microscopy (SEM)
Scanning electron microscopy (SEM) is a powerful tool in the domains of materials science, mining, and geology owing to its enormous potential to provide unique insight into micro and nanoscale worlds. The rapid pace of technological development requires a detailed study of minerals to a further extent to meet the unprecedented material demands of the evolving world. There are more than 5956 species of minerals known today, and the number of new identifications is evolving, with as many as 50 new types identified each year. Quantitative measurements and qualitative analyses of mineral compositions within mining ores and reservoirs have valuable importance with practical applications. Comprehensive and accurate information can be gathered for the identification of rocks and minerals, including structural characteristics and mineral composition, which can provide worthy information about pore structure and reservoir heterogeneity.
  • 4.2K
  • 29 Dec 2023
Topic Review
YOLOv5-AC
Attention Mechanism-Based Lightweight YOLOv5 for Track Pedestrian Detection. In response to the dangerous behavior of pedestrians roaming freely on unsupervised train tracks, the real-time detection of pedestrians is urgently required to ensure the safety of trains and people. Aiming to improve the low accuracy of railway pedestrian detection, the high missed-detection rate of target pedestrians, and the poor retention of non-redundant boxes, YOLOv5 is adopted as the baseline to improve the effectiveness of pedestrian detection by model pruning, improving attention mechanism, etc.
  • 4.2K
  • 15 Sep 2022
Topic Review
Large-Scale Piezoelectric-Based Aircraft Systems
A new approach in the development of aircraft and aerospace industry is geared toward increas-ing use of electric systems. An electromechanical (EM) piezoelectric-based system is one of the po-tential technologies that can produce a compactable system with a fast response and a high power density. However, piezoelectric materials generate a small strain, of around 0.1–0.2% of the original actuator length, limiting their potential in large-scale applications.
  • 4.2K
  • 20 Feb 2021
Topic Review
Anti-Aging Potentials of Methylene Blue
Methylene blue (MB), as the first fully man-made medicine, has a wide range of clinical applications. Apart from its well-known applications in surgical staining, malaria, and methemoglobinemia, the anti-oxidative properties of MB recently brought new attention to this century-old drug. Mitochondrial dysfunction has been observed in systematic aging that affects many different tissues, including the brain and skin. This leads to increased oxidative stress and results in downstream phenotypes under age-related conditions. MB can bypass Complex I/III activity in mitochondria and diminish oxidative stress to some degree. MB also shows broad spectrum UV absorption capability.
  • 4.2K
  • 13 Dec 2021
Topic Review
Intracardiac Nervous System
The intracardiac nervous system (IcNS), sometimes referred to as the “little brain” of the heart, is involved in modulating aspects of cardiac physiology. The IcNS is composed of neuronal and non-neuronal compartments intrinsic to the heart and includes afferent, efferent, and intra- neurons, using sympathetic, parasympathetic, and non-adrenergic, non-cholinergic neural transmitters, and forming feedback loops with the central (brain and spine) and peripheral (paravertebral ganglia) nervous systems.
  • 4.2K
  • 11 Nov 2021
Topic Review
Minnesota Multiphasic Personality Inventory
The Minnesota Multiphasic Personality Inventory (MMPI) is a standardized psychometric test of adult personality and psychopathology. Psychologists and other mental health professionals use various versions of the MMPI to help develop treatment plans, assist with differential diagnosis, help answer legal questions (forensic psychology), screen job candidates during the personnel selection process, or as part of a therapeutic assessment procedure. The original MMPI was developed by Starke R. Hathaway and J. C. McKinley, faculty of the University of Minnesota, and first published by the University of Minnesota Press in 1943. It was replaced by an updated version, the MMPI-2, in 1989 (Butcher, Dahlstrom, Graham, Tellegen, and Kaemmer). A version for adolescents, the MMPI-A, was published in 1992. An alternative version of the test, the MMPI-2 Restructured Form (MMPI-2-RF), published in 2008, retains some aspects of the traditional MMPI assessment strategy, but adopts a different theoretical approach to personality test development.
  • 4.2K
  • 17 Nov 2022
Topic Review
Climate Change Adaptation in Greenland
Climate change adaptation is a pressing issue in Greenland. The term climate change describes long-term changes to the climate system. Since the 1950s a stark rise in global temperatures has been observed. As climate change, whether natural or anthropogenic, impacts the livelihoods of people across the globe, responses i.e. ways to prepare and adjust under changing vulnerabilities become important. Such responses are commonly discussed under the term adaptation, "the process of adjustment to actual or expected climate and its effects", as defined by the IPCC. Geographically Greenland is situated between the Arctic and the Atlantic Ocean, with one third of the island being north of the Arctic Circle. Since the middle of the 20th century, the Arctic has been warming at about twice the global rate. Rising temperatures put increasing pressure on certain plant and tree species and contribute to Greenland's melting ice sheet. This affects and changes the livelihood of the Greenlandic population, particularly the Inuit people, which make up to 80 percent of the total population. Besides the decline of fish stocks, the country's landscape is changing: the melting ice reveals minerals, oil and gas. This has attracted interest from local and foreign investors for potential resource extraction. As new industries are accompanied by new job opportunities and potential wealth, lifestyles are changing. Greenland is in transition, in terms of biophysical as well as cultural and social conditions.
  • 4.2K
  • 20 Nov 2022
Topic Review
Variable-Pitch Propeller
A variable-pitch propeller or controllable-pitch propeller (CPP) is a type of propeller with blades that can be rotated around their long axis to change the blade pitch. Reversible propellers—those where the pitch can be set to negative values—can also create reverse thrust for braking or going backwards without the need to change the direction of shaft revolution.
  • 4.2K
  • 23 Nov 2022
Topic Review
Applications of Substrate-Integrated Waveguide
Substrate-integrated waveguide (SIW) is a modern day (21st century) transmission line that has recently been developed. This technology has introduced new possibilities to the design of efficient circuits and components operating in the radio frequency (RF) and microwave frequency spectrum. Microstrip components are very good for low frequency applications but are ineffective at extreme frequencies, and involve rigorous fabrication concessions in the implementation of RF, microwave, and millimeter-wave components. This is due to wavelengths being short at higher frequencies. Waveguide devices, on the other hand, are ideal for higher frequency systems, but are very costly, hard to fabricate, and challenging to integrate with planar components in the neighborhood. SIW connects the gap that existed between conventional air-filled rectangular waveguide and planar transmission line technologies including the microstrip.
  • 4.2K
  • 13 Apr 2022
Topic Review
Peptide/Protein Self-Assembly and Aggregation
The self-assembly of proteins is an essential process for a variety of cellular functions including cell respiration, mobility and division. On the other hand, protein or peptide misfolding and aggregation is related to the development of Parkinson’s disease and Alzheimer’s disease, among other aggregopathies.
  • 4.2K
  • 11 Nov 2020
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