JAOMAD Glossary U:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Intro
U—Means "Multivariable" when used in first alpha character position of ISA instrument function tag, means "Multifunction" when used in succeeding positions [see ANSI/ISA S5.1-1984 (R1992)].
UA—User Agent.
UART—Universal Asynchronous Receiver/Transmitter; MOS/LSI device which is complete subsystem that simultaneously transmits and receives asynchronous data in duplex or half duplex operation.
UCA—Utility Communication Architecture.
UCD—User-Centered Design; see definition.
UCR—UnderColor Removal; color separation control technique in color screen displays and printing.
UDDI—Universal Description, Discovery and Integration; industry initiative for a universal business registry (catalog) of Web services which was led by Ariba, IBM, Microsoft and others; designed to enable software to automatically discover and integrate with services on the Web; with UDDI browser, humans can also review information contained in the registry, which is network of servers on Internet similar to Domain Name System (DNS).
UDFB—User Defined Function Blocks; computing software which allows custom programming language to be integrated into logic function blocks.
UDP—User Datagram Protocol; TCP/IP transaction protocol used for applications such as remote network management and name service access; allows users to assign a name to physical or numbered address.
UEC—User Environment Component; part of X-Open environment.
UEM—Unified Enterprise Model; see definition.
UHF—Ultra High Frequency.
UI—UNIX® International; consortium to establish a standard UNIX®; also: User Interface.
UIL—User Interface Language.
UL—(Underwriters Laboratories, Inc.); independent laboratory in U.S. which establishes standards for commercial and industrial products, generally to protect people using them; UL listing indicates compliance with UL safety standards for electrical, mechanical, and fire hazards; compare with FM.
ULSI—Ultra Large Scale Integration; over 1 million components on single multifunction chip.
Ultra WideBand—Secure data communication network that spreads impulse energy over such wide frequency spectrum, the signal power falls near or within the noise floor making these signals extremely difficult to detect, intercept, or jam, and when combined with AES, virtually impossible to crack.
ULTRIX®—Operating system which is Digital Equipment Corporation's answer to UNIX®.
UMD—Universal Media Disc; format developed by Sony for more memory density in smaller size than DVDs
UML—Unified Modeling Language; standard notation for modeling of real-world objects as first step in developing an object oriented program; its notation is derived from and unifies notations of three object-oriented design and analysis methodologies: 1) Grady Booch's methodology for describing a set of objects and their relationships, 2) James Rumbaugh's Object-Modeling Technique (OMT), 3) Ivar Jacobson's approach which includes use case methodology.
UMS—Utilities Management System.
UMTS—Universal Mobile Telecommunications System; see definition.
Unbalanced Line—Digital transmission line in which magnitudes of voltages on the two conductors are not equal in respect to ground, such as coaxial line.
UNC—Universal Naming Convention; standard for identifying servers, printers and other resources in a network, which originated in UNIX community; UNC path uses double slashes or backslashes to precede name of computer, and path (disk and directories) within the computer are separated with a single slash or backslash, as in //servername/path; used for log-on commands to a communication network, especially Internet.
Underscan—Video display effect where image is shrunk so that it does not fill entire screen.
Undershoot—Difference between value to which a signal goes below setpoint, and value of desired setpoint.
UNECE—United Nations Economic Commission for Europe.
Ungrounded Junction—Form of construction of a thermocouple probe where hot, or measuring, junction is fully enclosed but electrically isolated from sheath.
UNI—(Ente Nationale Italiano di Unificazione).
Unicast—To transmit from one station to one other, such as from client to server or server to server; contrast with Multicast.
Unified Enterprise Model—Model developed by ARC Advisory Group to map all activities and their interrelationships which constitute all elements of performing business in any corporation; model is production-centric, and it not only allows, but encourages, the manufacturer to plan, control, and optimize the enterprise, plant, and design systems throughout the entire global enterprise.
Uniformity—In video displays, evenness of brightness across screen display, without which view appears dirty and colors are distorted.
Union—Pipe fitting type where two pipes are joined by separable flange-like coupling, which requires neither pipe to be rotated.
Unipolar—Electrical signal that is always positive, such as 1 to 5V.
Uniqueness—In Object Oriented Programming (OOP), each object which has a unique identification.
UNIVAC—UNIVersal Automatic Computer; weighing in at only 8 tons, this second modern computer was the leaner, meaner version of the military ENIAC, but designed for commercial use in 1950 by the same two designers (US Census Bureau became first enterprise computer customer on June 14, 1951); 46 copies of this first commercial computer were made, and the original, with its 2.25 MHz garage-sized CPU was used up to 1963; unlike its ENIAC sibling which required technicians to throw thousands of Manual switches to create a routine to run, this one was capable of storing a program fed into it; see ENIAC.
Universal Mobile Telecommunications System (UMTS)—One of third-generation (3G) cell phone wireless communication standard, which is also being developed into a 4G technology; allows communication with very high band with (2 Mbytes/sec) & next step in real mobile multimedia communication and applications (e.g. video communication, internet television).
Universal Playback—Web-based training that plays unaltered on any common computer system; Web browsers, the playback engines, exist for DOS/Windows, Apple Macintosh, and UNIX operating systems; although HTML, JAVA, and VRML, the languages of Web browsers, are undergoing rapid changes, these languages are not platform-specific; see Web-Based Training.
Universal Plug ‘n Play (UPnP)—Architecture, developed by Microsoft, for peer-to-peer network connectivity of PCs of all form factors, intelligent appliances, & wireless devices; distributed, open networking architecture using TCP/IP and the web to enable proximity networking in addition to control and data transfer between networked devices at home, office, or anywhere.
Universal Time Coordinated (UTC)—(Coordinated Universal Time, Temps Universel Coordonné); current international time standard (formerly Greenwich Mean Time, or GMT); Zero hours UTC is midnight in Greenwich, England, which is located at 0 degrees longitude with everything east of Greenwich (up to 180 degrees) is later in time and everything west is earlier; 42 time authorities around the world are constantly synchronizing with each other [In U.S., located at the U.S. Naval Observatory (USNO) and National Institute of Standards & Technology (NIST)]; See NTP.
UNIX®—UNIfied multi-tasking; time-sharing operating system designed originally by (and trademark of) AT&T for communicating, multi-user, 32-bit minicomputers which has become widely accepted because of its versatility; tradename now belongs to X/Open Corp. Ltd.
Unloaded Line—Analog transmission line which has no loading coils to reduce line loss, typically at audio frequencies like with telephone lines
UNMA—Unified Network Management Architecture by AT&T®.
Unmodeled behavior—In Plant Simulation, any plant activity that is not somehow included in the plant model.
UPC—Uniform Product Code; standard bar code printed on retail merchandise containing vendor's identification number and product number, which is read by passing bar code past a scanner.
Upgrade—Didn’t work the first time. J
Upper Range Value—Highest value of the measured variable that a device is adjusted to measure.
UPnP—Universal Plug ‘n Play; architecture by Microsoft to allow interconnection of various functions, applications, and modules by multiple suppliers; more at definition.
UPS—Uninterruptable Power Supply; used to ameliorate effects of poor electrical power quality, including voltage anomalies, high frequency noise, or ground loops; especially applicable where power outages of over half a second duration are possible.
Upscale Break Protection—Form of wire break detection which signals user that thermocouple has burned out.
URC—Universal Raster Coordinates.
URCLK—Universal Receiver Clock.
URL—Uniform Resource Locator; World Wide Web Internet address for source of information which also indicates what kind of information it is and where it is located within that source.
URV—Upper Range Value; see definition.
US/AS—Unified Sensor/Actuator Standard; international standard being developed by NEMA/IEEE for sensor and actuator network products and services.
USART—Universal Synchronous/Asynchronous Receiver/Transmitter.
USB—Universal Serial Bus; designed to allow user to easily plug in additional devices onto relatively short computer network without need to reboot computer; relies on computer microprocessor for operation.
USB Flash Drive—NAND-type flash memory data storage device integrated with a USB interface & typically removable and rewritable; called a drive because it is designed to read and write data using the same system commands as a mechanical disk drive, appearing to the computer operating system and user interface as just another drive.
User—Person using or having access to system, especially computer; sometimes refers to owner organization of purchased system
User Application—In FOUNDATION Fieldbus technology, is based on "blocks," including Resource Blocks (RBs), Function Blocks (FBs) and Transducer Blocks (TBs), which represent different types of application functions.
User-Centered Design—Computer application design that considers the needs of end user as paramount; in computer & web-based training design for example, user-centered means designing for maximum instructional effectiveness and usability while allowing the end user control over the learning process; in process control systems, it means making the operator interface so intuitive that it becomes “transparent.”
User-Friendly—Pertaining to any feature, device or concept that makes perfect sense to some computer programmer.J
User Layer—In FOUNDATION Fieldbus technology, provides scheduling of Function Blocks (FBs), as well as Device Descriptions (DDs) which allow the host system to communicate with devices without the need for custom programming.
Users—Collective term for those who stare vacantly at a computer monitor; users are divided into three types: novice, intermediate, and expert: * Novice Users are people who are afraid that simply pressing a key might break their computer.* Intermediate Users are people who don't know how to fix their computer after they've just pressed a key that broke it.* Expert Users are people who break other people's computers.J
USL—UNIX Systems Laboratories; an AT&T spin-off; also: Upper Sensor Limit (of a transmitter).
USNC/IEC—(United States National Committee for International Electrotechnical Commission).
USOC—Universal Service Order Code; set of phone company standards (U.S.) for equipment, including connectors and interfaces.
USRT—Universal Synchronous Receiver/Transmitter.
UST—Underground Storage Tank; under RCRA (U.S. federal law), a tank with more than 10% of its volume (and connected piping)
USTAG—(U.S. Technical Advisory Group); committee formed to work with IEC (international Electrotechnical Commission).
Utility Software (Program)—Programs that make operation of PC or LAN more convenient, including programs to move disk files more easily, diagnostic programs, etc.
UTC—Universal Time Coordinated; formerly GMT; see definition.
UTP—Unshielded Twisted Pair; wiring for signals consisting of at least two conductors twisted together six twists per inch to minimize effects of electromagnetic radiation between them, but without a metal covering to protect it from external EMI or RFI (compare with STP).
UUCICO—UNIX-to-UNIX Copy In/Copy Out; program which oversees remote connections in lieu of shell.
UUCP—UNIX-to-UNIX system CoPy service.
UUT—Unit Under Test.
UV—Ultra-Violet; that portion of electromagnetic spectrum below blue light (380 nanometers).
UVP—UnderVoltage Protection.
UWB—Ultra WideBand data communication network; see definition.
UXGA—Ultra eXtended Graphics Adapter (Array); video standard introduced as a refinement of SVGA which offers higher resolution of at least 1600 x 1200 pixels; see CGA, EGA, PGA, SVGA, VGA, XGA.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Intro