JAOMAD Glossary V:
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
V—Once meant "Viscosity," now means “Vibration” or “Mechanical Analysis” when used in first alpha character position of ISA instrument function tag, means "Valve"(damper, louver) when used in succeeding position [see ANSI/ISA S5.1-1984 (R1992)]; also: Volt(s); also: specific Volume, ft3/lb.
V-Mail—Video Mail; video counterpart of Electronic Mail; method of transmitting video as well as text messages and files (brochures, presentations, etc.) digitally over communication links, such as the phone system.
V&V—Verification and Validation, in software quality processes.
Validation tests—In Plant Simulation, exercises used to check the accuracy of plant model by applying identical inputs to both model and real plant, then comparing results.
Value Engineering—Total approach to design that achieves improved performance and quality by stressing simplicity and integration of design and manufacturing techniques.
Valve Positioner/Controller—Signal operated device installed to control valve operation, designed to assure given signal obtains desired action regardless of changes in friction or process pressures; that is, when a controller outputs a signal representing a specific valve opening to a positioner, a physical measure on valve stem determines actual position and changes positioner signal to actuator until that position matches the request.
Valve Travel—Distance over which valve is turned between its full closed and full opened positions.
VAN—Value Added Network; network whose services go beyond simple switching, often store & forward (mailbox) services to manage high volume message traffic, usually leased high bandwith networks between different geographical locations.
Vaporware—Computer software that is announced or advertised, but never shipped.J; as compared with Firmware, Hardware, Software, and Wetware.
VAR—Value Added Remarketer (or Reseller).
VAS—Value Added Services.
VAT—Voltage Adjusting Type; process control output.
VAV—Variable Air Volume.
VAX—Virtual Access eXtended; a product series from Digital Equipment Corp.
VB—Visual Basic; software programming that provides macro-type language and graphical environment; originally designed by Microsoft® as application-development environment which allows standard GUI bolted to some existing library.
VBA—Visual Basic for Applications; subset of Visual Basic that provides a common language for customizing Microsoft applications; supports COM, which allows a VBA script to invoke internal functions within Excel, Word and other COM-based programs or to make use of stand-alone, external COM objects.
VBX—Visual Basic eXtension; specialized applications typically written in C or C++ that embed themselves into VB environment; allows VB programmer to plug another software components into application without requiring any understanding of inner workings in that component; limitations include memory access, platform dependency, and speed; these were Microsoft's first component architecture, and 16-bit VBXs were superseded by 32-bit OCXs; see OCX & ActiveX.
VC—Virtual Component; usually some system with reusable intellectual property (software) embedded within a chip but capable of being combined with others to create various different combinations of systems.
VCF—Voltage Controlled Frequency.
VCG—Voltage Controlled Generation; mode of function generator.
VCI—Value Chain Initiative.
VCO—Voltage Controlled Oscillator.
VCP—Video Control Panel, term of reference from PLC operator interfaces.
VCPI—Virtual Control Protected Interface; single-tasking DOS extender, replaced by DPMI.
VCR—Video Cassette Recorder; also: Virtual Communication Relationships, see definition.
VDE—(Verband Deutscher Electrotechniker); Association of German Electrical Engineers who also act as independent European regulation and standards testing agency focused on electrical and electronic products; member of IEC as VDE-VERLAG GmbH.
VDF—Vacuum Fluorescent Display.
VDI—Virtual Device Interface; also: (Verein Deutscher Ingenieure), Association of German Engineers providing engineers from different fields of study with common representative body to promote positive cross-disciplinary interaction.
VDMAD—Virtual Direct Memory Access Driver; see DMA.
VDP—Video Disk Player.
VDR—Video Disk Recorder.
VDS—Variable Definition Syntax; this is DDL renamed, copyright granted to SP50 Committee by ISP Foundation; also: Video Direct Slot; provides port for additional video monitors using common signal source in a workstation.
VDT—Video Display Terminal.
VDU—Video Display Unit; also: Visual Display Unit.
Vector—Quantity that denotes both magnitude and direction; commonly represented by line segment with arrow; length represents magnitude; orientation in space and placement of arrow at one end of line represents direction.
Vector Control—In motion control, form of closed loop control to develop constant torque at varios speeds.
Vector Oriented Drawing—Approach in drawing and layout programs that treat graphics as line and arc segments rather than individual dots; also called Object Oriented.
Vector Quantity—Quantity that denotes both magnitude and direction in relation to given frame of reference; examples are displacement, velocity, force, and magnetic intensity.
Vectorscope—In analog video development, equipment used to precisely analyze various parts of video signal.
Verbose Format—Displaying meaningful words rather than alpha/numeric code.
VESA—(Video Electronics Standards Association).
VF—Vacuum Fluorescent type of liquid crystal displays (LCD).
VFD—Variable Frequency Drive; helps save energy and provide variable speed control with standard three-phase motors; they cut down on inrush current and mechanical stress during starting and can improve power factor; also: Vacuum Fluorescent Displays that emit fluorescent glow when exited with small voltage, a type of liquid crystal displays (LCD); also: Virtual Field Device, see definition.
VFW—Video For Windows; Microsoft® package for integrating video clips into other computer applications.
VGA—Video Graphics Adapter (Array); video standard introduced in 1987 for IBM® PS/2® series which can emulate CGA and EGA modes, and additionally provide 640 x 480 pixels with 16 colors and 320 x 200 pixels with 256 colors; see CGA, EGA, PGA, SVGA UXGA, XGA.
VGR—Vision Guided Robot; see definition.
VHDL—VHSIC Hardware Description Language used to design electronic systems at the component, board and system level; also: Very High Density Logic; also: Very High-level Design Language.
VHF—Very High Frequency.
VHLL—Very High Level Language; very application oriented computer programming language where burden on user is shifted away from understanding computers and learning codes, to simply understanding problem to be solved; while dramatically faster and easier to use, and providing a "top down" focus on thinking, they generally work well in only a narrow class of problem (spread sheet for an accountants is not useful word processing package for a fiction writer).
VHS—Video Home System, Matsushita® videotape standard.
VHSIC—[pronounced: vizik] Very High Speed Integrated Circuit; ultra-high-speed chips employing LSI and VLSI technologies.
VHV—Very High-speed Voltage; over 20,000 Volts.
Vibration Error—Maximum change in equipment or system performance when a specific amplitude and range of frequencies are applied to a specific axis at ambient conditions.
Video Card—Computer interface card that processes video data.
Videodisk—Optical storage medium for storing high quality audio information with random access capability.
Video for Windows—In digital graphics display, multimedia architecture and application suite that provides an outbound architecture that lets applications developers access audio, video, and animation from many different sources through one interface; as application, primarily handles video capture and compression, as well as video and audio editing.
Video Mining—Application of advanced computer technologies for using a combination of speech recognition, image understanding and natural-language processing techniques to open up the world's vast video archives to efficient computer searching; see Data Mining.
VideoRAM—Random Access Memory with parallel-to-serial conversion for video display signal generation.
Viewing Area—That part of video screen display which can be used in a given application, sometimes called Workspace.
Vise-Grips—Generally used after pliers to completely round off bolt heads. If nothing else is available, they can also be used to transfer intense welding heat to the palm of your hand. J
Vision Guided Robot (VGR)—Unlike blind robots, does not depend on costly precision fixtures to hold parts, additional labor to load and orient parts, or need upstream actuators, sorters and feeders to separate parts for processing; allows manufacturers to easily process various part types without tooling changeover; has added benefit of automatic collision avoidance for safer work cells.
VIL—Vertical Injection Logic.
VINES™—Virtual Network Software; operating software for LAN made by Banyan®.
Virtual Circuit—In packet switching, network facility that gives appearance to user of actual end-to-end circuit; dynamically variable network connection where sequential data may be routed differently during course of a "virtual connection;" virtual circuits enable transmission facilities to be shared by many users simultaneously; also called logical circuit.
Virtual Communication Relationships—In FOUNDATION Fieldbus technology, configured application layer channels that provide for the transfer of data between applications; FOUNDATION fieldbus describes three types of VCRs: : 1) publisher-subscriber, used for links between blocks and are scheduled; 2) client-server, used for the unscheduled transfer of view data; 3) report distribution also known as source-sink, is used to distribute trend and alarm information.
Virtual Community—Type of e-commerce site where group of people collaborate and share ideas over an electronic network (e.g. the internet); communities optimize their collective power by affiliating around a common interest, by compression of the time between member interactions (i.e. communicating in real time), and by asynchronous "postings" which potentially reach more participants and allow for more reflection time than real-time interactions; communities are organizing themselves via one community site.
Virtual Field Devices—In FOUNDATION Fieldbus technology, abstract model for description of data and behavior of automation system as seen by communication partner; used to remotely view local device data described in object dictionary; typical device will have at least two Virtual Field Devices (VFDs).
Virtual Memory (Storage)—Storage space that may be viewed as addressable main storage, but is actually auxiliary storage (usually peripheral storage) mapped into real addresses; amount of virtual storage is limited by addressing scheme of computer.
Virtual Private LAN Service (VPLS) —Multipoint virtual private network (VPN) service from carriers that connects any number of Ethernet LANs together over an IP core, typically using MultiProtocol Label Switching (MPLS), although other encapsulation protocols can be used; known as a "transparent LAN service" (TLS), from a customer's viewpoint, all connections appear as one Ethernet network, and all protocols in the customer's network (IP, IPX, etc.) are automatically supported.
Virtual Private Network (VPN)—In digital communications, software defined, switched-based network which emulates a private network, but on a non dedicated (not leased) public phone system, typically for video conferencing (which normally needs dedicated lines) also: software method for creating secure “tunnel” for secure communication between two end points over Internet.
Virtual Reality—Computer technology that simulates the plant environment with a high degree of reality; when combined with graphic 3D images and presented to a user, what he sees becomes "augmented reality" and this overlaying of images onto the virtual life brings him into an immersive, interactive, "augmented" environment
Virus—See Computer Viruses, Worms, & Trojan Horses.
VISCA—VIdeo Systems Control Architecture; protocol by Sony® for controlling its own Vdeck™ line of tape drives and Vbox™, which connects to Control L and other devices; open architecture allows third-party development as well, supported by numerous software applications.
Viscosity—Inherent resistance of a substance to flow.
Visemes—visual component of phonemes, which are the smallest individual component of speech; for each viseme, software uses nonlinear morphing technique that takes several dozen static pictures and blends them together to create fluid and accurate representation of someone speaking; see Phonemes.
VISRD—Virtual Interrupt Service Routine Driver; used to reduce interrupt latencies as a very effective way to avoid performance degradation in Windows™.
Visual Basic (VB)—Software programming that provides macro-type language and graphical environment; originally designed by Microsoft® as application-development environment which allows standard GUI bolted to some existing library.
Visual Engineering—Process of creating photo realistic images and animations from geometric and analytical data; used for product design, testing, and manufacturing directions, for analysis of complex mathematics or physics such as thermal dissipation and stress, and for ergonomic studies of human interaction with designs.
VIW—Video In Window; placing a continuous video image (from, say, an RGB input) into a computer (typically VGA) screen view.
VL bus—VESA Local bus; extension to 486 bus system.
VLAN—Video Local Area Network, created by Videomedia®.
VLDB—Very Large DataBases; generally corporate-wide data from all parts of an Enterprise, and including all activities.
VLF—Very Low Frequency; radiation in CRT-based video monitors; see ELF.
VLM—Very Large Memory, capacity up to 14 Gigabytes.
VLSI—Very Large Scale Integration; high density multifunction semiconductor device with 1,000 to 1 million components on a chip.
Vmax—In context of intrinsic safety, maximum open circuit voltage permitted in a hazardous area in an intrinsically safe installation; see Intrinsically Safe.
VME—Versa Module European; 32-bit bus and component system (IEEE-1014 1987); also: Virtual Machine Environment for real time control.
VMI—Vendor Managed Inventory.
VML—Vector Markup Language, another World Wide Web Consortium (W3C) standard describing graphics presentation and communication; see HTML.
VMS—Virtual Memory System.
VMX—Versa Module (European) eXtended; private bus.
VNet—Network of computers communicating via VPN, see Virtual Private Network.
Voc—In context of intrinsic safety, maximum open circuit voltage from barrier protecting a hazardous area in an intrinsically safe installation; see Intrinsically Safe.
VOC—Volatile Organic Compounds; a consideration in EPA (U.S.) regulations; highly evaporative organic material frequently found in paints, solvents, and similar products, contributing to formation of smog.
VOD—Video On Demand; commercial capability to select "private programming" independent of broadcast schedules due to multichannel availability of media such fiber optic cable; industrial implications in plant simulation exercises during operation.
Voice Grade Channel—Channel used for speech transmission usually with an audio frequency range of 300 to 3400 Hz; also: used for transmission of analog and digital data, up to 10,000bps.
VoIP—[pronounced: v-oy-p] Voice over Internet Protocol; category of hardware and software that enables people to use Internet as transmission medium for telephone calls by sending voice data in packets using IP rather than by traditional circuit transmissions of Public Switched Telephone Network, Internet telephony and VoIP are used interchangeably.
Volatile Memory—Storage medium that loses all data when power is removed.
Volume(tric) Flow Rate—Calculated using area of full closed conduit (A) and average fluid velocity (V) to arrive at total volume quantity of flow(Q); Q = VxA.
Vortals—Internet research group Delphi defines them as: Internet based business-to-business market communities that automate transactions required to build a value chain.
VPICD—Virtual Programmable Interrupt Controller Device; used by Windows™ to manage interrupt controller resources for multiple virtual machines (or tasks).
VPLS—Virtual Private LAN Service; see definition.
VPN—Virtual Private Network; see definition
VR—Virtual Reality; three dimensional (3-D) computer simulation of real world activities and events allowing "walk-through" of various proposed designs or situations; becomes 3-D doorway vs. 2-D window (video screen).
VRAM—Video Random Access Memory; provides capacity for number of colors and resolution (amount of pixels), optimized for video processing; unlike conventional RAM, VRAM can be accessed by two different devices simultaneously, the Random Access Memory Digital-to-Analog Converter to access the VRAM for screen updates at the same time that the video processor provides new data; also: Vertical MagnetoResitive Access Memory for MRAM design using donought-shaped magnetic structures similar in function to old core memory which reduces interference and eliminates need for transistors as used with magnetic tunneling junction designs, increasing density and stability; see MRAM; Magnetic Tunneling Junction.
VRC—Vertical Redundancy Check; error detection scheme in which parity bit of each character is set so that total number of "1" bits in character is odd (or even).
VRML—[pronounced: vermal] Virtual Reality Markup Language; computer authoring language to publish documents through World Wide Web on Internet using both text and three dimensional graphics, allowing user to shift direction, rotate, even “fly through” for different view of objects, using ordinary hardware and (mostly) free software.
VSD—Variable Speed Drive.
VSI—Virtual Socket Interface; industry standard methodology to allow various different predictable and pre-verified Intellectual Properties (IPs), generally in form of software available to interconnect to create various different systems, usually on chips, for specific user requirements.
VSS—Very Small Sensor; ultrasonic microtransducer and microprocessor based electronics.
VSWR—Voltage Standing Wave Ratio.
VT—Virtual Terminal; also: Vertical Tabulation, in data communication, format effector which advances the active position to same character position on the next predetermined line.
VTP—Virtual Terminal Protocol; emerging OSI standard to support terminal emulation.
VTR—Video Tape Recorder.
VVI—Variable Voltage Input; type of variable frequency drive; see VFD.
VVVF—Variable Voltage, Variable Frequency.
VXI—VME eXtensions for Instrumentation; open architecture multivendor standard to implement modular instruments.
V.xx Standards—Series of standards covering data communications over telephone circuits, established by CCITT.
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
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