0-9 A B C D E F G H I J K L M N O P Q R S T U V W XYZ

PREVIOUS PAGE         Return to ANSDIT

In a computer network, a subnetwork that connects end nodes or other subnetworks and that is characterized by high-speed data communications. Synonymous with backbone network.

backbone network:
Synonym for backbone.

back chaining:
Synonym for backward chaining.

back channel:
A transmission channel associated with a specific forward channel but with the opposite direction of transmission and used for supervisory or error control signals, or for response to the user. In case of simultaneous transfer of data in both directions, this definition applies with respect to the data source under consideration. Synonymous with backward channel.

background image:
That part of a display image, such as a form overlay, that is not changed during a particular sequence of transactions. Synonymous with static image.

background processing:
The execution of lower priority programs when higher priority programs are not using the system resources.

background tile:
A tile used to fill regions of a window when the contents of the window have been lost or have become invalid.

Illumination, reaching the image sensor, that is not reflected from the surface of the object, but is provided behind the object. Backlighting can be used to produce a silhouette of the workpiece.

back-lit display:
A display that uses a light source behind the image or screen.

back propagation:
In a multilayered network, the propagation of connection weights adjustment, layer by layer, from the output layer toward the input of the network. Typically back propagation is used in connection with error-correction learning.

back-propagation network (BPN):
In artificial neural network, a multilayered network using back propagation for connection weight adjustment during learning.

(1) To move a data medium or point of interaction backwards a specified distance. For example, to move a magnetic tape backwards by one block. (2) To move the print or display position backwards one position along the printing or display line.

backspace character (BS):
A format effector that causes the print or display position to move one position backward along the line without producing the printing or display of any graphic. The move backwards may cause moving to the last position of the previous line. In many text processors a backspace character also causes deletion.

In artificial intelligence, a search procedure in which the choice that leads to an unacceptable result causes the search to return to an earlier node to make another choice. The state represented by an earlier node cannot always be successfully recreated since some of the already executed instructions have irreversible side effects.

(1) The process of making a reserve copy of a file, of a document, etc. Synonymous with backup copy. (2) Pertaining to a procedure, technique, or hardware used to help recover lost or destroyed data or to keep a system operating.

backup copy:
Synonym for backup.

backup file:
A file made for possible later data restoration; for example, a copy of a file preserved at an alternate site.

backup procedure:
A procedure to provide for data restoration in case of a failure or a disaster; for example: making backup files.

Backus-Naur form (BNF):
A metalanguage used to specify or describe the syntax of a language in which each symbol, by itself, may represent a string set of symbols. Synonymous with Backus normal form.

Backus normal form:
Synonym for Backus-Naur form.

backward chaining:
An iterative paradigm for deriving inferences that starts with a goal rule whose truth value has to be determined, and goes backward through the rules of a system until a question is answered, a previously stored result is found, or until it is found that the truth value cannot be determined. Synonymous with back chaining.

backward channel:
Synonym for back channel.

backward LAN channel:
In a broadband LAN, the channel assigned for data transmission from the data stations to the headend. Synonymous with reverse LAN channel.

backward recovery:
The data reconstitution of an earlier version of data by using a later version and data recorded in a journal.

backward search:
In text processing, a function or mode that enables searching from any position in a document toward the beginning of the document. Synonymous with reverse find, reverse search.

A program that propagates itself by electronic mail to everyone in each recipient's distribution list. Synonymous with chain letter.

badge reader:
An input unit capable of reading data on specially encoded badges or cards.

bad sectoring:
A technique for copy protection in which bad sectors are intentionally written on a diskette.

balanced tree:
A tree in which the heights of the immediate subtrees of each node differ at most by one. Synonymous with height-balanced tree.

balanced error:
A set of errors whose mean value is zero.

(1) A group of tracks on a magnetic medium or optical medium all of which are read or written in parallel. The bands may be linear (as on magnetic tape) or annular (as on disks). (2) In data communications, the frequency spectrum between two defined limits. (3) Synonym for zone.

band printer:
An impact printer in which the character set available for printing is carried on a flexible band.

A relatively small area on a Web page with content independent from the remainder of the Web page; the content may be dynamic, contain audio, etc. For example, an advertisement.

bar code:
A code representing characters by sets of parallel bars of varying thickness and separation that are read optically by transverse scanning.

barf zone:
Within a virtual world, a region defined by a threshold of interaction within which nausea may occur.

To speak over a voice prompt and still be recognized correctly and answered appropriately. Experienced users may barge-in to improve a system's throughput because they already know the correct response.

bar printer:
An impact printer in which the type slugs are carried on a type bar.

barrel distortion:
A distortion such that the image of a scene appears to bulge outward on the sides much as the sides of a barrel. The distortion may be caused by a decrease in effective magnification as points in the image move away from the image center.

(1) In a floating-point representation, the number that is raised to the power denoted by the exponent and then multiplied by the coefficient to determine the number represented; for example: the number 10 in the expression 3.15 x 103 = 3150. The term "radix" is deprecated in this sense because of its use in radix notations. (2) A reference value. (3) A number that is multiplied by itself as many times as indicated by an exponent. Contrast with radix.

base address:
An address used as the origin in the calculation of addresses.

The original band of frequencies produced by a transducer, an electronic bit stream, or other signal initiating device and without translation in frequency by modulation of a carrier.

baseband LAN:
A local area network in which data are encoded and are transmitted without modulation of a carrier.

based literal:
A numeric literal used to represent a number in a form that expresses the radix explicitly. For example, in Ada, 16#F.FF#E+2 is a hexadecimal real literal representing the decimal literal 4095.

In text processing, the primary horizontal reference line for character alignment and measurement of vertical distances between lines.

base type:
A data type from which a subtype is descended. Synonymous with host type, underlying type. Contrast with parent type.

A procedural algebraic language with a small instruction set and originally designed to be interactive and for ease of learning. The name is the abbreviation derived from Beginner's All-Purpose Symbolic Instruction Code.

basic format:
Synonym for default format.

basic mode link control:
Control of data links by means of a character-oriented protocol using the standardized control characters of the 7-bit coded character set for information interchange.

bastion host:
A host computer that in a screened subnetwork performs the functions of a firewall. Synonymous with screened-host gateway.

Pertaining to a mode of operation of a functional unit in which inputs are collected and processed in groups, rather than being processed as each input arrives.

batch processing:
(1) The operating mode in which data or jobs, accumulated in advance, are processed in such a manner that the end user generally does not further influence the processing while it is in progress. (2) The processing of data accumulated over time. (3) Loosely, the execution of programs serially. (4) Pertaining to the technique of executing a set of programs such that each is completed before the next program of the set is started.

batch-processing environment:
An operating environment in which input data are collected and processed in groups, rather than being processed as each input arrives.

batch training:
Training in which the connection weights are adjusted only after each epoch is presented.

battery-powered calculator:
A calculator that depends solely for its power upon a chemical, solar, or rechargeable battery.

The unit of modulation rate equal to the number of signal elements per second where all such elements are of equal length and each element represents one or more bits. For some modems operating at or above 1200 bit/s, the modulation rate, expressed in bauds, is usually less than the bit rate because more than one bit is conveyed per signal element.

bulletin board system.

binary-coded decimal.

beaconing station:
A data station in a ring network that reports serious failures to neighboring stations.

A copy of a block or record before a modification.

beginning-of-file (BOF) label:
Synonym for header label.

beginning-of-tape (BOT) marker:
A marker on a magnetic tape used to indicate the beginning of the recordable area; for example, a photoreflective strip, or a transparent section of tape.

The bell character.

In artificial intelligence, a statement whose validity has a certainty factor attached to it. Beliefs help derive a conclusion from insufficient knowledge.

bell character (BEL):
The control character that is used when there is need to call for human attention and that may activate an alarm or other attention devices.

Bell-LaPadula security model:
An example of a computer security model.

belt printer:
An impact printer in which the character set available for printing is carried on a belt.

A test that uses a representative set of programs and data designed to evaluate the performance of computer hardware and software in a given configuration. Synonymous with benchmark test.

benchmark test:
Synonym for benchmark.

benign environment:
In computer security, a nonhostile environment protected from external threats by physical, human, and procedural security countermeasures.

bit error ratio.

Bernoulli box:
A removable floppy disk drive for personal computers that uses the Bernoulli effect to achieve close spacing between the read/write head and the recording medium.

best-first search:
A general procedure that maintains a set of partial paths toward a goal, evaluates each feasible next node for these paths based on predetermined evaluation criteria, and extends the path that has the best evaluation results.

between-the-lines entry:
In computer security, access obtained through active wiretapping by an unauthorized user to a momentarily inactive transmission channel connected to a legitimate user resource.

(1) A systematic deviation of a value from a reference value. (2) The amount by which the average of a set of values departs from a reference value.

biased exponent:
The characteristic in a floating-point representation in which the characteristic differs from the true exponent by a constant.

bias error:
An error due to bias; for example, an error caused by a shrunken measuring tape or an error caused by truncation in a computation.

Biba security model:
An example of a computer security model.

bidirectional list:
Synonym for symmetrical list.

bidirectional printer:
A printer that can print left to right and right to left. Synonymous with reverse printer.

bidirectional search:
A search that starts simultaneously by forward chaining and backward chaining and stops when the search paths meet in the solution space or when all possibilities have been exhausted.

(1) Pertaining to a selection, choice, or condition that has two possible different values or states. (2) Of a fixed-radix notation, having a radix of two .

binary arithmetic operation:
An arithmetic operation in which the operands and the result are represented in the pure binary system.

binary cell:
A storage cell that can hold one binary character.

binary character:
Either character of a binary character set; for example, T (true) or F (false), Y (yes) or N (no), 1 or 0.

binary character set:
A character set that consists of two characters.

binary code:
(1) A code that makes use of exactly two distinct characters, usually 0 and 1. (2) A code whose application results in a binary code set.

binary-coded decimal (BCD) notation:
A binary-coded notation in which each of the decimal digits is separately represented by a binary numeral. For example, in the binary-coded decimal notation that uses the weights 8-4-2-1, the decimal numeral 23 is represented by 0010 0011 as compared to its representation 10111 in the binary system. Synonymous with binary-coded decimal representation.

binary-coded decimal representation:
Synonym for binary-coded decimal notation.

binary-coded notation:
A binary notation in which each character is represented by a binary numeral.

binary code set:
A code set whose elements are constructed from a binary character set. Synonymous with binary code element set.

binary digit:
Synonym for bit.

binary digital signal:
Synonym for binary signal.

binary digit string:
Synonym for bit string.

binary element:
A constituent element of data that takes either of two values or states.

binary image:
In computer vision, an image consisting of pixels using only two values.

binary large object (blob):
A large quantity of data stored in a database, that cannot be interpreted by the database management system but is known by its size and location; for example an image file, a sound file.

binary morphology:
The application of mathematical morphology to binary images.

binary notation:
A notation that uses two different characters. For examples: T (true) or F (false), Y (yes) or N (no), 0 or 1. Binary notation is not restricted to the binary numeration system.

binary number:
Loosely, a binary numeral.

binary numeral:
A numeral in the binary system; for example: 101 is a binary numeral and V is the equivalent Roman numeral.

binary numeration system:
Synonym for binary system.

binary operator:
An operator whose operands and results are binary.

binary search:
A dichotomizing search that processes sets of an approximately equal number of data elements.

binary signal:
A digital signal in which the significant condition of each signal element has one of two permitted values. Synonymous with binary digital signal.

binary system:
The fixed-radix notation that uses the two digits 0 and 1, and a fixed radix of two, and the lowest integral weight of 1; for example, in the binary system, the numeral 110.01 represents 1 x 22 + 1 x 21 + 0 x 20 + 0 x 2-1 + 1 x 2-2 equivalent to the decimal numeral 6.25. Synonymous with binary numeration system.

binary tree:
An ordered tree in which each node has at most two other nodes that are directly subordinate.

In programming, to relate an identifier to an object; for example, to relate an identifier to a value or an address or to associate formal parameters and actual parameters.

bind an address:
To associate a symbolic address or a label with an absolute address, virtual address, or device identifier in a program. This concept is a special case of "to bind (a variable)".

binding time:
An instant at which binding takes place. For example, programming languages designed for both efficient execution and flexibility, such as Ada, PL/I and C++, provide for multiple options that allow choices of binding times.

Pertaining to the use of specific attributes that reflect unique personal characteristics, such as a fingerprint, an eye blood-vessel print, or a voice signature, to validate the identity of a person.

A branch of technology that relates the functions, characteristics, and phenomena of living systems to the development of mechanical systems.

A device that detects and converts bioelectrical signals into digitized signals.

biquinary code:
A notation in which each number n from 0 to 9 is represented by the pair of numerals a,b, where a is 0 or 1, b is 0, 1, 2, 3, or 4 so that the sum of 5a+b is equal to n. Generally, a and b are represented in the binary system.

Pertaining to an entity that is capable of assuming two stable states, one at a time.

bistable circuit:
Synonym for flip-flop.

bistable trigger circuit:
Synonym for flip-flop.

Next Page