U

U is for UML

UBE: Unsolicited Bulk Email: Email messages received but not requested from no one in particular about nothing in particular addressed to many, many people.

UCA™ (Utility Communications Architecture): comprising a set of communication protocols specified and/or developed for utilities. UCA version 2 protocol suites are oriented to RTUs and IEDs in substation and distribution automation. The ICCP (TASE .2) protocol suite is oriented for the exchange of real-time data between control center systems or other utility systems.

UCE: Unsolicited Commercial Email: Email messages received but not requested from a company or person trying to sell something.

UCTE - Union of Electric Energy Transmission Co-ordination that organizes system operators of Western and Central Europe whose systems cooperate synchronously.

UDDI (Universal Description, Discovery, and Integration): a project initiative by Ariba, IBM, and Microsoft, that creates a global, platform-independent, open framework to enable businesses to (1) discover each other, (2) define how they interact over the Internet, and (3) share information in a global registry that will more rapidly accelerate the global adoption of B2B eCommerce. The UDDI registry is provided as a web service. The UDDI specifications uses; e.g., XML, HTTP, DNS, and SOAP.

UDP (User Datagram Protocol): A connectionless transport layer protocol in the TCP/IP suite.

UML (Unified Modeling Language): UML is a graphical language, sponsored by OMG, that expresses program design in a standard way, allowing design tools to interchange models (using XMI). It's an object-oriented language that standardizes an impressive number of diagram types including; e.g., Class and Object diagrams, Structure diagrams, and Use Case diagrams. See also CORBA. More... Google Directory.

UN/CEFACT: United Nations Centre for Trade Facilitation and Electronic Business. It is open to participation from Member States, intergovernmental organizations, and sectoral and industry associations recognized by the Economic and Social Council of the United Nations (ECOSOC). The Centre's objective is to be "inclusive" and it actively encourages organizations to contribute and help develop its recommendations and standards. http://www.unece.org/cefact

Unavoidable Forces - Sudden, unforeseeable events remaining beyond control of the parties, preventing in all or in part the compliance with the contractual obligations for a specific period or for good, that cannot be prevented in spite of a due diligence exercised by the parties. The events recognized as the unavoidable forces are in particular as follows:

a) natural disasters, including fire, flood, drought, earthquake, hurricane, hoar-frost;
b) acts of the State authorities, including martial law, embargoes, blockades, etc.;
c) warfare, acts of sabotage;
d) general strikes or other social unrests, including public demonstrations, lockouts.

Unbundling: The separating of the total process of electric power service from generation to metering into its component parts for the purpose of separate pricing or service offerings.  [DOE Glossary of Electricity Terms]

Unguided Medium: A wireless transmission medium with no physical boundaries; e.g., radio.

Unicode: Global character encoding schema. Unicode provides a unique number for every character, no matter what the platform, program, or language. Unicode is required by modern standards such as HTML (RFC2070), XML, Java, ECMAScript, LDAP, and CORBA. Standardized in ISO/IEC 10646-1:2000. RFC2277 recommends the use of ISO 10646/Unicode to all new Internet protocols. Compare with ASCII.

Uninterruptible Power Supply (UPS): An uninterruptible power supply (UPS) is a device that allows key equipment to keep running for at least a short time when the primary power source is lost. It also often  provides protection from power surges. A UPS can be sized for individual computer systems or entire operations centers. It usually consists of a battery system that instantaneously provides power when the UPS senses a loss of power from the primary source, and sometimes a generator which can pick up the load within a few minutes. Typically the generator is a diesel engine, but other options include microturbines, fuel cells, and gas turbines, depending upon the size of the load and other factors.

UNIX: An operating system available for a wide range of computers. It is commonly referred to as the "operating system" of the Internet.

Unsolicited Message: Message transmitted in response to a locally occurring event, rather than an explicit remote request. Usually a Client requests a Server to start sending unsolicited messages whenever certain client-specified events occur.

Upload: To transfer a file from the local computer to a remote computer, normally done with ftp. The opposite is to download.

URI (Uniform Resource Identifier): The generic set of all names/addresses that are short strings that refer to resources.

URL (Uniform Resource Locator): An informal term (no longer used in technical specifications) associated with popular URI schemes: http, ftp, mailto, etc.

URN (Uniform Resource Name). (1) An URI that has an institutional commitment to persistence, availability, etc. Note that this sort of URI may also be a URL. See, for example, PURLs. (2) A particular scheme, URN:, specified by RFC2141 and related documents, intended to serve as persistent, location-independent, resource identifiers.

USENET (Newsgroups): Usenet is a worldwide distributed discussion system. It consists of over 30,000 news servers (or newsgroups) with names that are classified hierarchically by subject. "Articles" or "messages" are "posted" to these newsgroups by people on computers with the appropriate software -- these articles are then broadcast to other interconnected computer systems via a wide variety of networks. Over 10 Gigabytes of data is posted daily. news:

User - Any person, software application, or system that interacts directly with another computer system.

User ID: A unique character string that identifies users. The name a person uses to access a system during authentication. This name is often part, or complete e-mail address as well.

User Identification: User identification is the process by which a user identifies himself to the system as a valid user. (As opposed to authentication, which is the process of establishing that the user is indeed that user and has a right to use the system.)

User Interface: The part of an application that the user works with. User interfaces can be text-driven, such as DOS, or graphical, such as Windows.

Utility Distribution Companies (UDC): The entities that will continue to provide regulated services for the distribution of electricity to customers and serve customers who do not choose direct access. Regardless of where a consumer chooses to purchase power, the customer's current utility, also known as the utility distribution company, will deliver the power to the consumer's home, business, or farm.  [DOE Glossary of Electricity Terms]

UTP (Unshielded Twisted Pair): A cable that is twisted together to reduce noise and crosstalk

UUCP (Unix to Unix Copy Program): A store-and-forward system primarily for Unix systems but currently supported on other platforms.

Uuencode: An older method of encoding non-ASCII data for transmission over the Internet. Still used a lot in newsgroups, most newsreaders now automate the process although there are still times when one may require a UUdecoder.