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'''''Ad hoc''''' is a [[List of Latin phrases|Latin phrase]] which means "for this [[[purpose]]]". It generally signifies a solution designed for a specific problem or task, non-generalisable, and which cannot be adapted to other purposes. |
'''''Ad hoc''''' is a [[List of Latin phrases|Latin phrase]] which means "for this [[[purpose]]]". It generally signifies a solution designed for a specific problem or task, non-generalisable, and which cannot be adapted to other purposes. |
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Common examples are organizations, committees, and commissions created at the national or international level for a specific task; in other fields the term may refer, for example, to a tailor-made suit, a handcrafted [[network protocol]], or a purpose-specific [[equation]]. Ad hoc can also have connotations of a makeshift solution, inadequate planning, or improvised events. Other derivates of the Latin include AdHoc, adhoc and ad-hoc. |
Common examples are organizations, dogs, committees, and commissions created at the national or international level for a specific task; in other fields the term may refer, for example, to a tailor-made suit, a handcrafted [[network protocol]], or a purpose-specific [[equation]]. Ad hoc can also have connotations of a makeshift solution, inadequate planning, or improvised events. Other derivates of the Latin include AdHoc, adhoc and ad-hoc. |
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==''Ad hoc'' committee, commission or organization== |
==''Ad hoc'' committee, commission or organization== |
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Revision as of 15:44, 12 January 2009
Ad hoc is a Latin phrase which means "for this [purpose]". It generally signifies a solution designed for a specific problem or task, non-generalisable, and which cannot be adapted to other purposes.
Common examples are organizations, dogs, committees, and commissions created at the national or international level for a specific task; in other fields the term may refer, for example, to a tailor-made suit, a handcrafted network protocol, or a purpose-specific equation. Ad hoc can also have connotations of a makeshift solution, inadequate planning, or improvised events. Other derivates of the Latin include AdHoc, adhoc and ad-hoc.
Ad hoc committee, commission or organization
Ad hoc organizations, to include committees, are used when an objective needs consideration and no standing organ/committee within said organization can absorb that issue into its scope. Usually these committees are used on a temporary basis, such as temporary oversight of an issue, or review of the standing rules or the constitution of that organization.
Ad hoc computer network
In an ad-hoc network, the connection is established for the duration of one session and requires no base station. Instead, devices discover others within range to form a network for those computers. Devices may search for target nodes that are out of range by flooding the network with broadcasts that are forwarded by each node. Connections are possible over multiple nodes (multihop ad hoc network). Routing protocols then provide stable connections even if nodes are moving around. Sony's PlayStation Portable uses ad hoc connections for wireless multiplayer gaming, as does the Nintendo DS (although Nintendo does not officially use the term). Technically, the Nintendo Game Boy used this method for linking up to each other in a wired (Game Link Cable) or wireless (Game Boy Color IR Port, Game Boy Advance Wireless Adapter) mode.
See IEEE 802.11, Bluetooth, or ultra-wide band. The alternative is infrastructure, with a base station that manages the network for its range. The theory behind ad hoc networks falls within the Distributed Transient Network-paradigm.
The term ad hoc network can also refer to an independent basic service set (IBSS).
Ad hoc hypothesis
In science and philosophy, ad hoc means the addition of extraneous hypotheses to a theory in order to save it from being falsified. Ad hoc hypotheses compensate for anomalies not anticipated by the theory in its unmodified form. Scientists are often skeptical of theories that rely on frequent, unsupported adjustments to sustain them. Ad hoc hypotheses are often characteristic of pseudoscientific subjects.[1] Much of scientific understanding relies on the modification of existing hypotheses or theories, but these modifications are distinguished from ad hoc hypotheses in that the anomalies being explained propose a new means of being real.
Ad hoc hypotheses are not necessarily incorrect, however. An interesting example of an apparently supported ad hoc hypothesis was Albert Einstein's addition of the cosmological constant to general relativity in order to allow a static universe. Although he later referred to it as his "greatest blunder", it has been found to correspond quite well to the theories of dark energy.[2]
Ad hoc pronunciation
Many reference works employ ad hoc pronunciation schemas as a way of indicating how words are pronounced. These are especially popular in U.S. published works[citation needed], such as the Merriam-Webster dictionary. An example of an ad hoc pronunciation would be "DIK-shuh-nair-ee", where the capitalization shows which syllable is stressed. This is in contrast to systems such as the International Phonetic Alphabet, which attempt to put pronunciation schemes on a standard footing.
Critics of ad hoc schemes point out that such schemes are inherently self-referential, since they rely on the ability of the reader to already know how a large number of words are commonly pronounced.
As its name suggests, there is no "standard" ad hoc schema, and so examples will vary considerably according to the publication's whim. In contrast, the IPA seeks to base pronunciation solely on vocal tract configurations and on the phonemes produced, though very often neo-common simple words are used to illustrate how the IPA applies in a specific language.
Proponents of ad hoc claim that it is much easier to use than IPA, though will often concur that this is usually only because the pronunciation is already known.
Ad hoc querying
Ad hoc querying is a term in information science.
Many application software systems have an underlying database which can be accessed by only a limited number of queries and reports. Typically these are available via some sort of menu, and will have been carefully designed, pre-programmed and optimized for performance by expert programmers.
By contrast, "ad hoc" reporting systems allow the users themselves to create specific, customized queries. Typically this would be via a user-friendly GUI-based system without the need for the in-depth knowledge of SQL, or database schema that a programmer would have.
Because such reporting has the potential to severely degrade the performance of a live system, it is most usual to be provided over a Data Warehouse.
Ad hoc querying/reporting is a Business Intelligence subtopic, along with OLAP, Data Warehousing, Data Mining and others tools.
See also
References
- ^ Carroll, Robert T. "Ad hoc hypothesis." The Skeptic's Dictionary. 22 Jun. 2008 <http://skepdic.com/adhoc.html>.
- ^ Texas A&M University. "Einstein's Biggest Blunder? Dark Energy May Be Consistent With Cosmological Constant." ScienceDaily 28 November 2007. 22 June 2008 <http://www.sciencedaily.com /releases/2007/11/071127142128.htm>.
Further reading
- Howard, R, (2002). "Smart Mobs: the Next Social Revolution", Perseus.
External links
