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HandWiki is the world's largest wiki-style encyclopedia dedicated to science, technology and computing. It allows you to create and edit articles as long as you have external citations and login account. In addition, this is a content management environment that can be used for collaborative editing of original scholarly content, such as books, manuals, monographs and tutorials.

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Physics-Informed Neural Networks
Physics-informed neural networks (PINNs) are a type of universal function approximators that can embed the knowledge of any physical laws that govern a given data-set in the learning process, and can be described by partial differential equations (PDEs). They overcome the low data availability of some biological and engineering systems that makes most state-of-the-art machine learning techniques lack robustness, rendering them ineffective in these scenarios. The prior knowledge of general physical laws acts in the training of neural networks (NNs) as a regularization agent that limits the space of admissible solutions, increasing the correctness of the function approximation. This way, embedding this prior information into a neural network results in enhancing the information content of the available data, facilitating the learning algorithm to capture the right solution and to generalize well even with a low amount of training examples.
  • 2.2K
  • 28 Nov 2022
Topic Review
Mars Oxygen ISRU Experiment
The Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE) is a technology demonstration on the NASA Mars 2020 rover Perseverance investigating the production of oxygen on Mars. On April 20, 2021, MOXIE produced oxygen from carbon dioxide in the Martian atmosphere by using solid oxide electrolysis. This was the first experimental extraction of a natural resource from another planet for human use. The technology may be scaled up for use in a human mission to the planet to provide breathable oxygen, oxidizer, and propellant; water may also be produced by combining the produced oxygen with hydrogen. The experiment was a collaboration between the Massachusetts Institute of Technology, the Haystack Observatory, the NASA/Caltech Jet Propulsion Laboratory, and other institutions.
  • 2.6K
  • 28 Nov 2022
Topic Review
Atmospheric Radiative Transfer Codes
An Atmospheric radiative transfer model, code, or simulator calculates radiative transfer of electromagnetic radiation through a planetary atmosphere, such as the Earth's.
  • 730
  • 28 Nov 2022
Topic Review
Half-Reaction
A half reaction (or half-cell reaction) is either the oxidation or reduction reaction component of a redox reaction. A half reaction is obtained by considering the change in oxidation states of individual substances involved in the redox reaction. Often, the concept of half reactions is used to describe what occurs in an electrochemical cell, such as a Galvanic cell battery. Half reactions can be written to describe both the metal undergoing oxidation (known as the anode) and the metal undergoing reduction (known as the cathode). Half reactions are often used as a method of balancing redox reactions. For oxidation-reduction reactions in acidic conditions, after balancing the atoms and oxidation numbers, one will need to add H+ ions to balance the hydrogen ions in the half reaction. For oxidation-reduction reactions in basic conditions, after balancing the atoms and oxidation numbers, first treat it as an acidic solution and then add OH− ions to balance the H+ ions in the half reactions (which would give H2O).
  • 5.6K
  • 28 Nov 2022
Topic Review
Rpm
RPM Package Manager (RPM) (originally Red Hat Package Manager; now a recursive acronym) is a package management system. The name RPM refers to the following: the .rpm file format, files in the .rpm file format, software packaged in such files, and the package manager program itself. RPM was intended primarily for Linux distributions; the file format is the baseline package format of the Linux Standard Base. Even though it was created for use in Red Hat Linux, RPM is now used in many Linux distributions. It has also been ported to some other operating systems, such as Novell NetWare (as of version 6.5 SP3), IBM's AIX (as of version 4), CentOS, Fedora (operating system) created jointly between Red Hat and the Fedora community, and Oracle Linux. All versions or variants of the these Linux operating systems use the RPM Package Manager. An RPM package can contain an arbitrary set of files. The larger part of RPM files encountered are “binary RPMs” (or BRPMs) containing the compiled version of some software. There are also “source RPMs” (or SRPMs) files containing the source code used to produce a package. These have an appropriate tag in the file header that distinguishes them from normal (B)RPMs, causing them to be extracted to /usr/src on installation. SRPMs customarily carry the file extension “.src.rpm” (.spm on file systems limited to 3 extension characters, e.g. old DOS FAT).
  • 2.4K
  • 28 Nov 2022
Topic Review
Emission Standard
Emission standards are the legal requirements governing air pollutants released into the atmosphere. Emission standards set quantitative limits on the permissible amount of specific air pollutants that may be released from specific sources over specific timeframes. They are generally designed to achieve air quality standards and to protect human life.
  • 2.6K
  • 29 Nov 2022
Topic Review
Orgasm
Orgasm (from Greek ὀργασμός, orgasmos; "excitement, swelling") or sexual climax is the sudden discharge of accumulated sexual excitement during the sexual response cycle, resulting in rhythmic, involuntary muscular contractions in the pelvic region characterized by sexual pleasure. Experienced by males and females, orgasms are controlled by the involuntary or autonomic nervous system. They are usually associated with involuntary actions, including muscular spasms in multiple areas of the body, a general euphoric sensation and, frequently, body movements and vocalizations. The period after orgasm (known as the refractory period) is typically a relaxing experience, attributed to the release of the neurohormones oxytocin and prolactin as well as endorphins (or "endogenous morphine"). Human orgasms usually result from physical sexual stimulation of the penis in males (typically accompanying ejaculation) and of the clitoris in females. Sexual stimulation can be by self-practice (masturbation) or with a sex partner (penetrative sex, non-penetrative sex, or other sexual activity). The health effects surrounding the human orgasm are diverse. There are many physiological responses during sexual activity, including a relaxed state created by prolactin, as well as changes in the central nervous system such as a temporary decrease in the metabolic activity of large parts of the cerebral cortex while there is no change or increased metabolic activity in the limbic (i.e., "bordering") areas of the brain. There is also a wide range of sexual dysfunctions, such as anorgasmia. These effects affect cultural views of orgasm, such as the beliefs that orgasm and the frequency or consistency of it are either important or irrelevant for satisfaction in a sexual relationship, and theories about the biological and evolutionary functions of orgasm.
  • 10.0K
  • 30 Nov 2022
Topic Review
Facet (Psychology)
In psychology, a facet is a specific and unique aspect of a broader personality trait. Both the concept and the term "facet" were introduced by Paul Costa and Robert McCrae in the first edition of the NEO-Personality Inventory (NEO-PI) Manual. Facets were originally elaborated only for the neuroticism, openness to experience, and extraversion traits; Costa and McCrae introduced facet scales for the agreeableness and conscientiousness traits in the Revised NEO-PI (NEO PI-R). Each of the Big Five personality traits in the five factor model contains six facets, each of which is measured with a separate scale. The use of facets and facet scales has since expanded beyond the NEO PI-R, with alternative facet and domain structures derived from other models of personality. Examples include the HEXACO model of personality structure, psycholexical studies, circumplex models (e.g., Goldberg's Abridged Big-Five Dimensional Circumplex), the Multidimensional Personality Questionnaire (MPQ), and the California Psychological Inventory.
  • 1.7K
  • 28 Nov 2022
Topic Review
Eyelash Extensions
Eyelash extensions are used to enhance the length, curliness, fullness, and thickness of natural eyelashes. The extensions may be made from several materials including mink, synthetic, or horse hair. The main method of applying the extensions is by using an adhesive glue to individually stick the extensions to the eyelash line. False eyelashes and eyelash extensions are not the same.
  • 2.3K
  • 28 Nov 2022
Topic Review
Mental Disorders Diagnosed in Childhood
Mental disorders diagnosed in childhood are divided into two categories: childhood disorders and learning disorders. These disorders are usually first diagnosed in infancy, childhood, or adolescence, as laid out in the DSM-IV-TR and in the ICD-10. The DSM-IV-TR includes ten subcategories of disorders including mental retardation, Learning Disorders, Motor Skills Disorders, Communication Disorders, Pervasive Developmental Disorders, Attention-Deficit and Disruptive Behavior Disorders, Feeding and Eating Disorders, Tic Disorders, Elimination Disorders, and Other Disorders of Infancy, Childhood, or Adolescence.
  • 1.9K
  • 28 Nov 2022
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