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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Scanning Kelvin Probe
In microscopy, a scanning Kelvin probe (SKP) is a non-contact, non-destructive scanning probe microscopy (SPM) technique used to measure the work function of the sample under study. By raster scanning in the x,y plane the work function of the sample can be locally mapped for correlation with sample features. It is predominantly used to measure corrosion and coatings. It is closely related to the Kelvin probe force microscope (KPFM) technique.
  • 1.8K
  • 30 Oct 2022
Topic Review
Hot Dry Rock Geothermal Energy
Hot dry rock (HDR) is an extremely abundant source of geothermal energy that is difficult to access. A vast store of thermal energy is contained within hot – but essentially dry and impervious crystalline basement rocks found almost everywhere deep beneath Earth's surface. A concept for the extraction of useful amounts of geothermal energy from HDR originated at the Los Alamos National Laboratory in 1970, and Laboratory researchers were awarded a U.S. patent covering it. This technology has been tested extensively with multiple deep wells drilled in several field areas around world including the USA, Japan, Australia, France, and the UK and investment of billions of research funds. It continues to be the focus along with a related technique called EGS for sizable government-led research studies involving costly deep drilling and rock studies. Thermal energy has been recovered in reasonably sustainable tests over periods of years and in some cases electrical power generation was also achieved. However no commercial projects are ongoing or likely due to the high cost and limited capacity of the engineered reservoirs, associated wells, and pumping systems. Commonly tests have opened just one or more fractures such that the reservoir surface heat exchange areas are limited. For this technology to successfully compete with other energy sources, drilling costs would have to drop drastically or new approaches that result in much more extensive, complex, and higher rate flow paths through actual fracture networks would have to be established. The enthusiasim evident here on Wikipedia and in the research community is justified by the vast extent of the energy supply and the low environmental impact of the method however significant breakthroughs will be required to make this a commercial energy resource.
  • 7.3K
  • 30 Oct 2022
Topic Review
SoftEther VPN
SoftEther VPN is free open-source, cross-platform, multi-protocol VPN client and VPN server software, developed as part of Daiyuu Nobori's master's thesis research at the University of Tsukuba. VPN protocols such as SSL VPN, L2TP/IPsec, OpenVPN, and Microsoft Secure Socket Tunneling Protocol are provided in a single VPN server. It was released using the GPLv2 license on January 4, 2014. The license was switched to Apache License 2.0 on January 21, 2019. SoftEther VPN supports NAT traversal, making it useful to run VPN servers on computers that are behind residential gateways, facility routers, and firewalls. Firewalls performing deep packet inspection are unable to detect SoftEther's VPN transport packets as a VPN tunnel because HTTPS is used to camouflage the connection. SoftEther VPN optimizes performance by using full Ethernet frame utilization, reducing memory copy operations, parallel transmission, and clustering. Together, these reduce latency normally associated with VPN connections while increasing throughput. The SoftEther VPN Server is unable to bind to specific IP addresses on a machine, negating one of its biggest features. A server running an SSL website cannot run SoftEther on the same machine, thereby preventing it from using the SSL-VPN tunnel functionality that the software is famous for.
  • 3.8K
  • 30 Oct 2022
Topic Review
Homelessness
Homelessness is the circumstance when people are without a permanent dwelling, such as a house or apartment. People who are homeless are most often unable to acquire and maintain regular, safe, secure and adequate housing. The legal definition of homeless varies from country to country, or among different jurisdictions in the same country or region. The term homeless may also include people whose primary night-time residence is in a homeless shelter, a domestic violence shelter, long-term residence in a motel, a vehicle, squatting, cardboard boxes, a tent city, tarpaulins, shanty town structures made of discarded building materials or other ad hoc housing situations. According to the UK homelessness charity Crisis, a home is not just a physical space: it also provides roots, identity, security, a sense of belonging and a place of emotional wellbeing. United States government homeless enumeration studies also include people who sleep in a public or private place not designed for use as a regular sleeping accommodation for human beings. There are a number of organizations who provide help for the homeless. In 2005, an estimated 100 million (1 in 65 at the time) people worldwide were homeless and as many as 1 billion people live as squatters, refugees or in temporary shelter, all lacking adequate housing. In Western countries, the majority of homeless are men (50–80%), with single males particularly overrepresented. However, current data suggests similar rates of homeless males and females. Most countries provide a variety of services to assist homeless people. These services often provide food, shelter (beds) and clothing and may be organized and run by community organizations (often with the help of volunteers) or by government departments or agencies. These programs may be supported by the government, charities, churches and individual donors. Many cities also have street newspapers, which are publications designed to provide employment opportunity to homeless people. While some homeless have jobs, some must seek other methods to make a living. Begging or panhandling is one option, but is becoming increasingly illegal in many cities. People who are homeless may have additional conditions, such as physical or mental health issues or substance addiction; these issues make resolving homelessness a challenging policy issue. Homeless people, and homeless organizations, are sometimes accused or convicted of fraudulent behaviour. Criminals are also known to exploit homeless people, ranging from identity theft to tax and welfare scams. These incidents often lead to negative connotations on the homeless as a group.
  • 4.0K
  • 30 Oct 2022
Topic Review
Traditional Chinese Timekeeping
The traditional Chinese time systems refers to the time standards for divisions of the day used in China until the introduction of the Shixian calendar in 1628 at the beginning of the Qing dynasty.
  • 6.2K
  • 30 Oct 2022
Topic Review
Spectrochemistry
Spectrochemistry is the application of spectroscopy in several fields of chemistry. It includes analysis of spectra in chemical terms, and use of spectra to derive the structure of chemical compounds, and also to qualitatively and quantitively analyze their presence in the sample. It is a method of chemical analysis that relies on the measurement of wavelengths and intensity of electromagnetic radiation.
  • 1.1K
  • 30 Oct 2022
Topic Review
Developmental Psychology
Developmental psychology is the scientific study of how and why human beings change over the course of their life. Originally concerned with infants and children, the field has expanded to include adolescence, adult development, aging, and the entire lifespan. Developmental psychologists aim to explain how thinking, feeling, and behaviors change throughout life. This field examines change across three major dimensions: physical development, cognitive development, and social emotional development. Within these three dimensions are a broad range of topics including motor skills, executive functions, moral understanding, language acquisition, social change, personality, emotional development, self-concept, and identity formation. Developmental psychology examines the influences of nature and nurture on the process of human development, and processes of change in context across time. Many researchers are interested in the interactions among personal characteristics, the individual's behavior, and environmental factors, including the social context and the built environment. Ongoing debates in regards to developmental psychology include biological essentialism vs. neuroplasticity and stages of development vs. dynamic systems of development. Developmental psychology involves a range of fields, such as educational psychology, child psychopathology, forensic developmental psychology, child development, cognitive psychology, ecological psychology, and cultural psychology. Influential developmental psychologists from the 20th century include Urie Bronfenbrenner, Erik Erikson, Sigmund Freud, Jean Piaget, Barbara Rogoff, Esther Thelen, and Lev Vygotsky.
  • 7.1K
  • 30 Oct 2022
Topic Review
Prospective Memory
Prospective memory is a form of memory that involves remembering to perform a planned action or recall a planned intention at some future point in time. Prospective memory tasks are common in daily life and range from the relatively simple to extreme life-or-death situations. Examples of simple tasks include remembering to put the toothpaste cap back on, remembering to reply to an email, or remembering to return a rented movie. Examples of highly important situations include a patient remembering to take medication or a pilot remembering to perform specific safety procedures during a flight. In contrast to prospective memory, retrospective memory involves remembering people, events, or words that have been encountered in the past. Whereas retrospective memory requires only the recall of past events, prospective memory requires the exercise of retrospective memory at a time that has not yet occurred. Prospective memory is thus considered a form of "memory of the future". Retrospective memory involves the memory of what we know, containing informational content; prospective memory focuses on when to act, rather than focusing on informational content. There is some evidence demonstrating the role of retrospective memory in the successful execution of prospective memory, but this role seems to be relatively small.
  • 3.7K
  • 30 Oct 2022
Topic Review
Catholic Bible
Within Catholicism, the Bible comprises the whole 73-book canon recognized by the Catholic Church, including the deuterocanonical books. It is sometimes referred to as the Catholic Bible.
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  • 30 Oct 2022
Topic Review
Denotational Semantics of the Actor Model
The denotational semantics of the Actor model is the subject of denotational domain theory for Actors. The historical development of this subject is recounted in [Hewitt 2008b].
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  • 30 Oct 2022
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