Summary

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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Edict of Thessalonica
The Edict of Thessalonica (also known as Cunctos populos), issued on 27 February AD 380 by three reigning Roman emperors, made the catholicism[note 1] of Nicene Christians in the Great Church the state church of the Roman Empire. It condemned other Christian creeds such as Arianism as heresies of "foolish madmen," and authorized their persecution.
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  • 12 Oct 2022
Topic Review
Damping Ratio
Damping is an influence within or upon an oscillatory system that has the effect of reducing, restricting or preventing its oscillations. In physical systems, damping is produced by processes that dissipate the energy stored in the oscillation. Examples include viscous drag in mechanical systems, resistance in electronic oscillators, and absorption and scattering of light in optical oscillators. Damping not based on energy loss can be important in other oscillating systems such as those that occur in biological systems and bikes. The damping ratio is a dimensionless measure describing how oscillations in a system decay after a disturbance. Many systems exhibit oscillatory behavior when they are disturbed from their position of static equilibrium. A mass suspended from a spring, for example, might, if pulled and released, bounce up and down. On each bounce, the system tends to return to its equilibrium position, but overshoots it. Sometimes losses (e.g. frictional) damp the system and can cause the oscillations to gradually decay in amplitude towards zero or attenuate. The damping ratio is a measure describing how rapidly the oscillations decay from one bounce to the next. The damping ratio is a system parameter, denoted by ζ (zeta), that can vary from undamped (ζ = 0), underdamped (ζ < 1) through critically damped (ζ = 1) to overdamped (ζ > 1). The behaviour of oscillating systems is often of interest in a diverse range of disciplines that include control engineering, chemical engineering, mechanical engineering, structural engineering, and electrical engineering. The physical quantity that is oscillating varies greatly, and could be the swaying of a tall building in the wind, or the speed of an electric motor, but a normalised, or non-dimensionalised approach can be convenient in describing common aspects of behavior.
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  • 12 Oct 2022
Topic Review
Click Farm
A click farm is a form of click fraud, where a large group of low-paid workers are hired to click on paid advertising links for the click fraudster (click farm master or click farmer). The workers click the links, surf the target website for a period of time, and possibly sign up for newsletters prior to clicking another link. For many of these workers, clicking on enough ads per day may increase their revenue substantially and may also be an alternative to other types of work. It is extremely difficult for an automated filter to detect this simulated traffic as fake because the visitor behavior appears exactly the same as that of an actual legitimate visitor. Fake likes generating from click farms are essentially different from those arising from bots where computer programs are written by software experts. To deal with such issues, companies such as Facebook are trying to create algorithms that seek to wipe out accounts with unusual activity (e.g. liking too many pages in a short period of time).
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  • 12 Oct 2022
Topic Review
Project Naptha
Project Naptha is a browser extension software for Google Chrome that allows users to highlight, copy, edit and translate text from within images. It was created by developer Kevin Kwok, and released in April 2014 as a Chrome add-on. This software was first made available only on Google Chrome, downloadable from the Chrome Web Store. It was then made available on Mozilla Firefox, downloadable from the Mozilla Firefox add-ons repository but was soon removed. The reason behind the removal remains unknown. The web browser extension uses advanced imaging technology. Similar technologies have also been employed to produce hardcopy art, and the identification of these works. By adopting several Optical Character Recognition (OCR) algorithms, including libraries developed by Microsoft Research and Google, text is automatically identified in images. The OCR enables the build-up of a model of text regions, words and letters from all images. The OCR technology that Project Naptha adopts is a slightly differentiated technology in comparison to the technology used by software such as Google Drive and Microsoft OneNote to facilitate and analyse text within images. Project Naptha also makes use of a method called Stroke Width Transform (SWT), developed by Microsoft Research in 2008 as a form of text detection.
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  • 12 Oct 2022
Topic Review
Space Toilet
A space toilet, or zero gravity toilet is a toilet that can be used in a weightless environment. In the absence of weight, the collection and retention of liquid and solid waste is directed by use of air flow. Since the air used to direct the waste is returned to the cabin, it is filtered beforehand to control odor and cleanse bacteria. In older systems, waste water is vented into space, and any solids are compressed and stored for removal upon landing. More modern systems expose solid waste to vacuum pressures to kill bacteria, which prevents odor problems and kills pathogens.
  • 2.4K
  • 12 Oct 2022
Topic Review
Christianity and Science
Most sources of knowledge available to early Christians were connected to pagan world-views. There were various opinions on how Christianity should regard pagan learning, which included its ideas about nature. For instance, among early Christian teachers, Tertullian (c. 160–220) held a generally negative opinion of Greek philosophy, while Origen (c. 185–254) regarded it much more favorably and required his students to read nearly every work available to them. Historically, Christianity has often been a patron of sciences. It has been prolific in the foundation of schools, universities and hospitals, and many clergy have been active in the sciences. Historians of science such as Pierre Duhem credit medieval Catholic mathematicians and philosophers such as John Buridan, Nicole Oresme and Roger Bacon as the founders of modern science. Duhem concluded that "the mechanics and physics of which modern times are justifiably proud to proceed, by an uninterrupted series of scarcely perceptible improvements, from doctrines professed in the heart of the medieval schools".
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  • 12 Oct 2022
Topic Review
Criticism of Facebook
Facebook (and parent company Meta Platforms) has been the subject of criticism and legal action. Criticisms include the outsize influence Facebook has on the lives and health of its users and employees, as well as Facebook's influence on the way media, specifically news, is reported and distributed. Notable issues include Internet privacy, such as use of a widespread "like" button on third-party websites tracking users, possible indefinite records of user information, automatic facial recognition software, and its role in the workplace, including employer-employee account disclosure. The use of Facebook can have negative psychological effects that include feelings of sexual jealousy, and stress, a lack of attention, and social media addiction that in some cases is comparable to drug addiction. Facebook's operations have also received coverage. The company's electricity usage, tax avoidance, real-name user requirement policies, censorship policies, handling of user data, and its involvement in the United States PRISM surveillance program have been highlighted by the media and by critics. Facebook has come under scrutiny for 'ignoring' or shirking its responsibility for the content posted on its platform, including copyright and intellectual property infringement, hate speech, incitement of rape, violence against minorities, terrorism, fake news, Facebook murder, crimes, and violent incidents live-streamed through its Facebook Live functionality. The company and its employees have also been subject to litigation cases over the years, with its most prominent case concerning allegations that CEO Mark Zuckerberg broke an oral contract with Cameron Winklevoss, Tyler Winklevoss, and Divya Narendra to build the then-named "HarvardConnection" social network in 2004, instead allegedly opting to steal the idea and code to launch Facebook months before HarvardConnection began. The original lawsuit was eventually settled in 2009, with Facebook paying approximately $20 million in cash and 1.25 million shares. A new lawsuit in 2011 was dismissed. Some critics point to problems which they say will result in the demise of Facebook. Facebook has been banned by several governments for various reasons, including Syria, China, Iran and Russia.
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  • 14 Oct 2022
Topic Review
Mitigation of Global Warming in Australia
Mitigation of global warming involves taking actions to reduce greenhouse gas emissions and to enhance sinks aimed at reducing the extent of global warming. This is in distinction to adaptation to global warming, which involves taking action to minimize the effects of global warming. Scientific consensus on global warming, together with the precautionary principle and the fear of non-linear climate transitions, is leading to increased effort to develop new technologies and sciences and carefully manage others in an attempt to mitigate global warming. In order to make a significant change, coal from Australia needs to be replaced with alternatives. Carbon capture and storage in Australia has been put forward as a solution for production of clean hydrogen from natural gas. Following the introduction of government mandatory renewable energy targets, more opportunities have opened up for renewable energy technologies such as wind power, photovoltaics, and solar thermal technologies. The deployment of these technologies provides opportunities for mitigating greenhouse gases. A carbon price was introduced on 1 July 2012 by the government of Julia Gillard with the purpose of reducing Australia 's carbon emissions. It requires large businesses (defined as those with annual carbon dioxide equivalent emissions over 25,000 tonnes annually) to pay a price for emissions permits. The tax was scrapped by the Abbott government in July 2014 in what was a widely criticized and highly publicized move.
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  • 12 Oct 2022
Topic Review
Google+
Google Plus (stylized as Google+) is an Internet-based social network that is owned and operated by Google. The service, Google's fourth foray into social networking, experienced strong growth in its initial years, although usage statistics have varied, depending on how the service is defined. Three Google executives have overseen the service, which has undergone substantial changes leading to a redesign in November 2015. On October 8, 2018, Google announced that it was shutting down Google+ for consumers, citing low user engagement and a software error, first reported by The Wall Street Journal , that potentially exposed the data of hundreds of thousands of users. Google indicated that Google+ would operate until August 2019, allowing users to download and migrate their information.
  • 5.9K
  • 12 Oct 2022
Topic Review
Mass Concentration
In chemistry, the mass concentration ρi (or γi) is defined as the mass of a constituent mi divided by the volume of the mixture V. For a pure chemical the mass concentration equals its density (mass divided by volume); thus the mass concentration of a component in a mixture can be called the density of a component in a mixture. This explains the usage of ρ (the lower case Greek letter rho), the symbol most often used for density.
  • 3.0K
  • 12 Oct 2022
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