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.

Expand All
Entries
Topic Review
The Sickness Unto Death
The Sickness Unto Death (Danish: Sygdommen til Døden) is a book written by Danish philosopher Søren Kierkegaard in 1849 under the pseudonym Anti-Climacus. A work of Christian existentialism, the book is about Kierkegaard's concept of despair, which he equates with the Christian concept of sin, which he terms, "the sin of despair."
  • 3.1K
  • 16 Nov 2022
Topic Review
Country Code Top-Level Domains with Commercial Licenses
Country code top-level domains with commercial licenses are Internet country code top-level domain that have adopted a policy for worldwide commercial use. Some of the world's smallest countries have opened their country code domain to worldwide registrations for commercial purposes. For example, Tuvalu and the Federated States of Micronesia, small island-states in the Pacific, have partnered with VeriSign and FSM Telecommunications respectively, to sell domain name registrations using the TV and fm TLDs to television and radio stations. Some commercially available ccTLDs are in demand for use outside their home countries because their name can provide a component of a meaningful word or phrase. These are sometimes referred to as vanity ccTLDs.
  • 666
  • 16 Nov 2022
Topic Review
F-Ratio
In oceanic biogeochemistry, the f-ratio is the fraction of total primary production fuelled by nitrate (as opposed to that fuelled by other nitrogen compounds such as ammonium). The ratio was originally defined by Richard Eppley and Bruce Peterson in one of the first papers estimating global oceanic production. This fraction was originally believed significant because it appeared to directly relate to the sinking (export) flux of organic marine snow from the surface ocean by the biological pump. However, this interpretation relied on the assumption of a strong depth-partitioning of a parallel process, nitrification, that more recent measurements has questioned.
  • 1.4K
  • 16 Nov 2022
Topic Review
Shubnikov–De Haas Effect
An oscillation in the conductivity of a material that occurs at low temperatures in the presence of very intense magnetic fields, the Shubnikov–De Haas effect (SdH) is a macroscopic manifestation of the inherent quantum mechanical nature of matter. It is often used to determine the effective mass of charge carriers (electrons and electron holes), allowing investigators to distinguish among majority and minority carrier populations. The effect is named after Wander Johannes de Haas and Lev Shubnikov.
  • 2.3K
  • 16 Nov 2022
Topic Review
DriveSpace
DriveSpace (initially known as DoubleSpace) is a disk compression utility supplied with MS-DOS starting from version 6.0 in 1993 and ending in 2000 with the release of Windows Me. The purpose of DriveSpace is to increase the amount of data the user could store on disks by transparently compressing and decompressing data on-the-fly. It is primarily intended for use with hard drives, but use for floppy disks is also supported. This feature was removed in Windows XP and later.
  • 892
  • 16 Nov 2022
Topic Review
Foreman
Foreman (also known as The Foreman) is an open source complete life cycle systems management tool for provisioning, configuring and monitoring of physical and virtual servers. Foreman has deep integration to configuration management software, with Ansible, Puppet, Chef, Salt and other solutions through plugins, which allows users to automate repetitive tasks, deploy applications, and manage change to deployed servers. Foreman provides provisioning on bare-metal (through managed DHCP, DNS, TFTP, and PXE-based unattended installations), virtualization and cloud. Foreman provides comprehensive, auditable interaction facilities including a web frontend, a command line interface, and a robust REST API.
  • 1.4K
  • 16 Nov 2022
Topic Review
Ebidding
An ‘‘‘electronic bidding system ‘‘‘ is an electronic bidding event (without awarding commitment) according to defined negotiation rules (eAgreement). A buyer and two or more suppliers take part in this online event.
  • 899
  • 16 Nov 2022
Topic Review
Passover (Christian Holiday)
Some Christians observe a form of the Jewish holiday of Passover. The practice is found among Assemblies of Yahweh, Messianic Jews, and some congregations of the Church of God (Seventh Day). It is often linked to the Christian holiday and festival of Easter. Often, only an abbreviated seder is celebrated to explain the meaning in a time-limited ceremony. The redemption from the bondage of sin through the sacrifice of Christ is celebrated, a parallel of the Jewish Passover's celebration of redemption from bondage in the land of Egypt. Christian Passover ceremonies are held on the evening corresponding to 14 Nisan (e.g. April 5, 2012) or 15 Nisan, depending whether the particular church uses a quartodeciman or quintodeciman application. In other cases, the holiday is observed according to the Jewish calendar on 15 Nisan, which is also used by Samaritans.
  • 1.8K
  • 16 Nov 2022
Topic Review
Born–Oppenheimer Approximation
In quantum chemistry and molecular physics, the Born–Oppenheimer (BO) approximation is the best-known mathematical approximation in molecular dynamics. Specifically, it is the assumption that the wave functions of atomic nuclei and electrons in a molecule can be treated separately, based on the fact that the nuclei are much heavier than the electrons. Due to the larger relative mass of a nucleus compared to an electron, the coordinates of the nuclei in a system are approximated as fixed, while the coordinates of the electrons are dynamic. The approach is named after Max Born and J. Robert Oppenheimer who proposed it in 1927, in the early period of quantum mechanics. The approximation is widely used in quantum chemistry to speed up the computation of molecular wavefunctions and other properties for large molecules. There are cases where the assumption of separable motion no longer holds, which make the approximation lose validity (it is said to "break down"), but even then the approximation is usually used as a starting point for more refined methods. In molecular infrared spectroscopy, using the BO approximation means considering molecular energy as a sum of independent terms, e.g.: [math]\displaystyle{ E_\text{total} = E_\text{electronic} + E_\text{vibrational} + E_\text{rotational} + E_\text{nuclear spin}. }[/math] These terms are of different orders of magnitude and the nuclear spin energy is so small that it is often omitted. The electronic energies [math]\displaystyle{ E_\text{electronic} }[/math] consist of kinetic energies, interelectronic repulsions, internuclear repulsions, and electron–nuclear attractions, which are the terms typically included when computing the electronic structure of molecules.
  • 2.6K
  • 16 Nov 2022
Topic Review
Chimera (Mythology)
The Chimera (/kɪˈmɪərə/ or /kaɪˈmɪərə/, also Chimaera (Chimæra); Greek: Χίμαιρα, Chímaira "she-goat") was, according to Greek mythology, a monstrous fire-breathing hybrid creature of Lycia in Asia Minor, composed of the parts of more than one animal. It is usually depicted as a lion, with the head of a goat arising from its back, and a tail that might end with a snake's head, and was one of the offspring of Typhon and Echidna and a sibling of such monsters as Cerberus and the Lernaean Hydra. The term Chimera has come to describe any mythical or fictional animal with parts taken from various animals, or to describe anything composed of very disparate parts, or perceived as wildly imaginative, implausible, or dazzling. The sight of a Chimera was an omen for disaster.
  • 9.1K
  • 16 Nov 2022
  • Page
  • of
  • 863

Other Entry Collections

>>