39210
`
`IEEE Dictionary IEEES
`
`INTERACTIVE
`
`IEEE 100
`The Authoritative Dictionary of
`IEEE Standards Terms
`
`Seventh Edition
`
`Published by
`Standards Information Network
`IEEE Press
`
`

`

`39210
`
`IEEE Dictionary IEEES
`
`INTERACTIVE
`
`Trademarks and disclaimers
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`

`39210 IEEE Dictionary IEEES
`
`BATCH
`
`indexed access
`
`546
`
`indicating control switch
`
`tively. (C) (electronic computation) Pertaining to an index
`register.
`(C) [20], [85]
`(2)
`(A) (data management) A data item that identifies a
`particular element in a set of items such as an array. (B) (data
`management) A list or table used to locate records within an
`indexed file that contains the location and unique key value
`of each record. Synonym: directory. See also: alternate index;
`cross-index. (C) (data management) To prepare a table as
`in definition (B).
`(C) 610.5-1990
`indexed access The process of accessing stored data in such a
`way that indices are used to locate records within data storage.
`Synonym: keyed access. See also: indexed sequential access.
`(C) 610.5-1990w
`indexed address An address that must be added to the contents
`of an index register to obtain the address of the storage lo-
`cation to be accessed. Synonym: variable address. See also:
`self-relative address; offset; relative address.
`(C) 610.12-1990, 610.10-1994w
`indexed addressing An addressing mode in which an index
`register or index word is used to permit automatic modifica-
`tion of the referred address without altering the instruction.
`Note: Particularly useful when programming repetitive in-
`struction sequences on many sets of data.
`
`(C) 610.10-1994w
`index dip (fiber optics) A decrease in the refractive index at
`the center of the core, caused by certain fabrication tech-
`niques. Sometimes called profile dip. See also: refractive in-
`dex profile.
`(Std100) 812-1984w
`indexed file A file that may be accessed using an index. Con-
`trast: partitioned data set; sequential file.
`
`(C) 610.5-1990w
`indexed segment In a database, a segment that is located by an
`indexing segment. Synonym: index target segment.
`(C) 610.5-1990w
`indexed sequential access The process of accessing stored data
`using the indexed sequential access mode. Contrast: direct
`access; sequential access. See also: indexed access.
`(C) 610.5-1990w
`indexed sequential access method (ISAM) An access method
`by which data records may be stored and retrieved using ei-
`ther the sequential access method or the direct access method.
`See also: basic sequential access method; virtual sequential
`access method.
`(C) 610.5-1990w
`indexed sequential access mode An access mode in which data
`records may be stored and retrieved using either direct access
`mode or sequential access mode. Note: The records are ac-
`tually stored in a sequential fashion, but an index is main-
`tained to allow direct access. Contrast: direct access mode;
`sequential access mode.
`(C) 610.5-1990w
`INDEX file The file within an exported catalog containing the
`metadata describing the software objects and attributes for all
`bundles, products, subproducts and filesets.
`(C/PA) 1387.2-1995
`index hole A hole found in hard-sectored media, such as mag-
`netic disks, or paper tape, in which the hole indicates the start
`of the first sector, the first record, or the top of the form.
`Contrast: index mark.
`(C) 610.10-1994w
`indexing segment In a database, a segment that contains a
`pointer to another segment, called the indexed segment, con-
`taining data. Synonym: index pointer segment.
`(C) 610.5-1990w
`index mark A mark found on soft-sectored media, such as mag-
`netic disks, in which a magnetic indicator is placed on the
`disk to indicate the beginning of each track within the sector.
`Synonym: address mark.
`(C) 610.10-1994w
`index matching material (fiber optics) A material, often a liq-
`uid or cement, whose refractive index is nearly equal to the
`core index, used to reduce Fresnel reflections from a fiber end
`face. See also: mechanical splice; refractive index; Fresnel
`reflection.
`(Std100) 812-1984w
`
`index of cooperation, international (facsimile in rectilinear
`scanning) The product of the total length of a scanning or
`recording line by the number of scanning or recording lines
`per unit length divided by pi. Notes: 1. For rotating devices
`the index of cooperation is the product of the drum diameter
`times the number of lines per unit length. 2. The prior IEEE
`index of cooperation was defined for rectilinear scanning or
`recording as the product of the total line length by the number
`of lines per unit length. This has been changed to agree with
`international standards.
`(COM) 168-1956w
`index of illuminant metamerism (illuminating engineering)
`(of two objects that are metameric when illuminated by a
`reference source) Measure of the degree of color difference
`between the two objects when a specified test source is sub-
`stituted for the reference source.
`(EEC/IE) [126]
`index of observer metamerism (illuminating engineering) (of
`two objects that are metameric when viewed by a reference
`observer) Measure of the degree of color difference between
`the two objects when a specfied test observer is substituted
`for the reference observer.
`(EEC/IE) [126]
`index of refraction See: refractive index.
`index of sensation (illuminating engineering) (of a source) A
`number that expresses the effects of source luminance (Ls),
`solid angle factor (Q), position index (P), and the field lu-
`minance (F) on discomfort glare rating.
`
`M ⫽
`
`LsQ
`0.44
`PF
`
`(See solid angle factor for an equation defining Q). Note: A
`restatement of this formula lends itself more directly to com-
`puter applications. See also: discomfort glare rating.
`(EEC/IE) [126]
`index pointer segment See: indexing segment.
`index profile (fiber optics) In an optical waveguide, the refrac-
`tive index as a function of radius. See also: step index profile;
`profile parameter; power-law index profile; profile dispersion
`parameter; parabolic profile; graded index profile; profile dis-
`persion.
`(Std100) 812-1984w
`index register (1) (computers) A register whose content is
`added to or subtracted from the operand address prior to or
`during the execution of an instruction.
`(MIL/C) [2], [85]
`(2) A register whose contents can be used to modify an op-
`erand address during the execution of computer instructions;
`it can also be used as a counter. Note: may be used to control
`the execution of a loop, to control the use of an array, for
`table lookup or as a pointer. Synonyms: cycle counter; B-box;
`B-line.
`(C) 610.10-1994w
`index target segment See: indexed segment.
`index word In indexed addressing, a word containing an index
`modifier that is applied to the address field of a computer
`instruction.
`(C) 610.10-1994w
`indicated bearing (direction finding systems) A bearing from
`a direction-finder site to a target transmitter obtained by av-
`eraging several readings: the indicated bearing is compared
`to the apparent bearing to determine accuracy of the equip-
`ment. See also: navigation.
`(AES/RS) 686-1982s, [42]
`indicated bearing offset (navigation aid terms) (direction
`finder [DF] installations) The mean different between the
`indicated and apparent bearings of a number of signal sources,
`the sources being, for the most part, uniformly distributed in
`azimuth.
`(AES/GCS) 172-1983w
`indicated value (A) (power meters) The uncorrected value de-
`termined by observing the indicating display of the instru-
`ment. (B) A scale reading or displayed value.
`(IM/NI) 470-1972, 544-1975, N42.17B-1989
`indicating circuit That portion of the control circuit of a control
`apparatus or system that carries the results of logic functions
`to visual or audible devices that indicate the state of the ap-
`paratus controlled.
`(IA/MT) 45-1998
`indicating control switch A switch that indicates its last control
`operation.
`(SWG/PE) C37.100-1992
`
`

`

`39210
`
`IEEE Dictionary IEEES
`
`BATCH
`
`indicating demand meter
`
`547
`
`indirect-acting machine voltage regulator
`
`indicating demand meter (metering) A demand meter
`equipped with a readout that indicates demand, maximum
`demand, or both.
`(ELM) C12.1-1982s
`indicating fuse A fuse that automatically indicates that the fuse
`has interrupted the circuit.
`(SWG/PE) C37.40-1993, C37.100-1992
`indicating instrument (glass industry) (electrical heating ap-
`plications to melting furnaces and forehearths in the glass
`industry) An instrument in which only the present value of
`the quantity measured is visually indicated.
`
`(IA) 668-1987w
`indicating or recording mechanism (demand meter) That
`mechanism that indicates or records the measurement of the
`electrical quantity as related to the demand interval. Note:
`This mechanism may be operated directly by and be a com-
`ponent part of the electric mechanism, or may be structurally
`separate from it. The demand may be indicated or recorded
`in kilowatts, kilovolt-amperes, amperes, kilovars, or other
`suitable units. This mechanism may be of an indicating type,
`indicating by means of a pointer related to its position on a
`scale or by means of the cumulative reading of a number of
`dial or cyclometer indicators: or a graphic type, recording on
`a circular or strip chart: or of a printing type, recording on a
`tape. It may record the demand for each demand interval or
`may indicate only the maximum demand. See also: demand
`meter.
`(EEC/PE) [119]
`indicating scale (recording instrument) A scale attached to
`the recording instrument for the purpose of affording an easily
`readable value of the recorded quantity at the time of obser-
`vation. Note: For recording instruments in which the produc-
`tion of the graphic record is the primary function, the chart
`scale should be considered the primary basis for accuracy
`ratings. For instruments in which the graphic record is sec-
`ondary to a control function the indicating scale may be more
`accurate and more closely related to the control than is the
`chart scale. See also: moving element.
`(EEC/PE) [119]
`indication (1) (supervisory control, data acquisition, and au-
`tomatic control) (station control and data acquisition) An
`audio or visual signal that signifies a particular condition.
`(PE/SUB) C37.1-1994
`(2) A light or other signal (audio or visual) provided by the
`man/machine interface that signifies a particular condition.
`(SWG/PE) C37.100-1992
`(3) A mechanism informing an entity of the occurrence of an
`event in a lower layer entity. Alternatively, an indication may
`provide evidence of a request by a remote station entity.
`(EMB/MIB) 1073.4.1-2000
`indication (status) function The capability of a supervisory
`system to accept, record, or display, or do all of these, the
`status of a device. The status of a device may be derived from
`one or more inputs giving the following two or more states
`of indication: Two-state indication. Only one of the two pos-
`sible positions of the supervised device is displayed at one
`time. Such display may be derived from a single set of con-
`tacts.; Three-state indication. One in which the transitional
`state or security indication as well as the terminal positions
`of the supervised device is displayed. Such a display is de-
`rived from at least two sets of initiating contacts; Multistate
`indication. Only one of the predefined states (transitional or
`discrete, or both) is indicated at a time. Such a display is
`derived from multiple inputs; Indication with memory. An
`indication function with the additional capability of storing
`single or multiple changes of status that occur between scans.
`(SUB/PE) C37.1-1994
`indication point (railway practice) The point at which the train
`control or cab signal impulse is transmitted to the locomotive
`or vehicle apparatus from the roadway element.
`(EEC/PE) [119]
`indication (status) point interfaces Master Station or RTU (or
`both) element(s) that accept(s) a digital input signal for the
`function of
`indication. The input/output elements of a
`SCADA system provide the physical interface to external de-
`
`vices. It is preferred that a point serve one of the functions
`described below. In some earlier applications, a Control and
`Indication (C and I) point has been used to specify a combi-
`nation control and indication point for a specific device (e.g.,
`circuit breaker). The functions are: Two-state indication. Only
`one of the two possible positions of the supervised device is
`displayed at one time. Such display may be derived from a
`single set of contacts. Tree-state indication One in which the
`transitional state or security indication as well as the terminal
`positions of the supervised device is displayed. Such a display
`is derived from at least two sets of initiating contacts; Mul-
`tistate indication. Only one of the predefined states (transi-
`tional or discrete, or both) is indicated at a time. Such a dis-
`play is derived from multiple inputs; Indication with memory
`An indication function with the additional capability of stor-
`ing single or multiple changes of status that occur between
`scans.
`(SUB/PE) C37.1-1994
`indication with memory See: supervisory control functions.
`indicator (1) (faulted circuit indicators) That portion of the
`FCI (faulted circuit indicator) which indicates that fault cur-
`rent has been sensed.
`(T&D/PE) 495-1986w
`(2) (software) A device or variable that can be set to a pre-
`scribed state based on the results of a process or the occur-
`rence of a specified condition. For example, a flag or sema-
`phore.
`(C) 610.12-1990
`(3) See also: display.
`indicator light A light that indicates whether or not a circuit is
`energized. See also: appliance outlet.
`(IA/APP) [90]
`indicators (Class 1E power systems for nuclear power gen-
`erating stations) Devices that display information to the op-
`erator.
`(PE/NP) 380-1975w, 308-1980s
`indicator symbol (logic diagrams) A symbol that identifies the
`state or level of an input or output of a logic symbol with
`respect to the logic symbol definition.
`(GSD) 91-1973s
`indicator travel The length of the path described by the indi-
`cating means or the tip of the pointer in moving from one end
`of the scale to the other. Notes: 1. The path may be an arc or
`a straight line. 2. In the case of knife-edge pointers and others
`extending beyond the scale division marks, the pointer shall
`be considered as ending at the outer end of the shortest scale
`division marks. See also: moving element.
`(EEC/EMI) [112]
`indicator tube An electron-beam tube in which useful infor-
`mation is conveyed by the variation in cross section of the
`beam at a luminescent target.
`(ED) 161-1971w, [45]
`indices Plural form of index.
`(C) 610.5-1990w
`indicial admittance The instantaneous response to unit step
`driving force. Note: This is a time function that is not an
`admittance of the type defined under admittance. See also:
`network analysis.
`(Std100) 270-1966w
`indicial response (process control) The output of a system or
`element, expressed as a function of time, when forced from
`initial equilibrium by a unit-step input. Note: In the time do-
`main, it is the graphic statement of the characteristic of a
`system or element analogous to the frequency-response char-
`acteristic of the transfer function.
`(PE/EDPG) [3]
`indigenous error A computer program error that has not been
`purposely inserted as part of an error-seeding process.
`(C) 610.12-1990
`indigenous fault (software) A fault existing in a computer pro-
`gram that has not been inserted as part of a fault seeding
`process. See also: fault seeding; fault; computer program.
`(C/SE) 729-1983s
`indirect-acting machine voltage regulator A machine voltage
`regulator having a voltage-sensitive element that acts indi-
`rectly, through the medium of an interposing device such as
`contractors or a motor, to control the excitation of an electric
`machine. Note: A regulator is called a generator voltage reg-
`ulator when it acts in the field circuit of a generator and is
`called an exciter voltage regulator when it acts in the field
`circuit of the main exciter.
`(SWG/PE) C37.100-1992
`
`