log-offThe procedure that is followed by a user in closing a session, e.g., a period of terminal operation. Synonym log out.
log-periodic (LP) antennaA broadband, multi-element, unidirectional, narrow-beam antenna that has impedance and radiation characteristics that are regularly repetitive as a…
log-structured file system (LFS)A file system that avoids both multiple-write and synchronous-write problems by batching large numbers of writes into large, contiguous writes.
logical connectorOne of the reserved words AND, OR and XOR used to build complex logical expressions in a query.
logical data replicationA type of on-line data replication that replicates logical transactions that change either the filesystem or the database.
logical driveA volume that you create within an extended partition on a basic master boot record (MBR) disk.
logical errorAn error in the logical of a method or class. Such an error might not lead to an immediate runtime error, but could have a significant impact on overall…
logical expressionA combination of items, system items, system variables, literals and arithmetic logical operators from which a value of TRUE or FALSE is derived; for…
logical link control (LLC) sublayerIn a local-area-network/metropolitan-area-network (LAN/MAN) system, the part of the link level that (a) supports medium-independent data link functions…
logical nameA case-sensitive unique string within an AWS CloudFormation template that identifies a resource, mapping, parameter, or output.
logical operatorAnother term for Boolean operator. See Boolean expression.
logical operatorsOperators, such as &&, ||, &, | and ^ that take two boolean operands and produce a boolean result.
logical processora hyperthreading CPU present itself as multiple logical CPUs to the operating system so that the OS will schedule threads on all of the logical CPUs…
logical selectionThe process of selecting a subset of features from a coverage using logical expression that operates on the attributes of coverage features (e.g.
logical signaling channelA logical channel that provides a signaling path within an information channel or within a physical signaling channel.
logical topologyOf a network, the schematic configuration that reflects the network's function, use, or implementation without regard to the physical interconnection of…
loginThe procedure that is followed by a user in beginning a session, e.g., a period of terminal operation. Synonym logon.
LogisticsThe science of planning and carrying out the movement and maintenance of forces.
Logistics SupportThe supply and maintenance of materiel essential to proper operation of a system in the force.
Logistics Support Analysis (LSA)The selective application of scientific and engineering efforts undertaken during the acquisition process, as part of the systems engineering process, to…
Logistics Support Analysis Record (LSAR)A formal tool under MIL-STD 1388-2A that uses records/forms to document operations and maintenance requirements, RAM, task analyses, technical data…
Logistics SupportabilityThe degree to which planned logistics support (including test, measurement, and diagnostic equipment; spares and repair parts; technical data; support…
longA term signifying ownership of securities. "I am long 100 XYZ," means that the speaker owns 100 shares of XYZ.
Long Lead ItemsThose components of a system for which the times to design and fabricate are the longest, and, therefore, to which an early commitment of funds may be…
long lineA transmission line in a long-distance communications network. Note: Examples of long lines are TDM and FDM carrier systems, microwave radio links…
long silent intervalA silent interval during a ringing cycle or pattern that lasts at least 1200 ms. [T1.401-1998]
Long TailPhrase describing how for any category of product being sold there is much more aggregate demand for the non-hits than there is for the hits.
Long Term RetentionRetention of data for 5 years to satisfy requirements for local studies and to support litigation.
long transactionLong transactions support applications where changes to a database might span several days, weeks or months and may involve several sessions.
long wavelengthIn fiber optic communications, pertaining to optical wavelengths greater than 1 m.
Long Wavelength Infrared (LWIR)Thermal radiation emitted by a source in the electromagnetic spectrum encompassing infrared wavelengths of 6 to 30 microns.
long-distance callAny telephone call to a destination outside the local service area of the calling station, whether inter-LATA or intra-LATA, and for which there is a…
long-haul communicationsIn public switched networks, pertaining to circuits that span large distances, such as the circuits in inter-LATA, interstate, and international…
long-term bit error rateBit error rate measured over a sufficiently long period, for example, one month. [T1.226-1992]
long-term recordRecords that have enduring value to the organization
long-term stabilityOf an oscillator, the degree of uniformity of frequency over time, when the frequency is measured under identical environmental conditions, such as supply…
LongitudeThe location east or west in reference to the Prime Meridian, which is designated as zero (0) degrees longitude.
longitudinal balanceThe electrical symmetry, with respect to ground, of the two wires of a pair 2. An expression of the difference in impedance of the two sides of a circuit.
longitudinal balance-audioThe ratio of the disturbing longitudinal source voltage, Vs, and the resultant metallic voltage, Vm, at the same frequency of the network under test…
longitudinal voltageA voltage induced or appearing along the length of a transmission medium. Note 1: Longitudinal voltage may be effectively eliminated by using differential…
look-and-feelThe visual impression and interaction style provided by a user interface. This is predominantly the responsibility of the window manager (in collaboration…
lookaheadAn "assertion" that peeks at the string to the right of the current match location.
lookbehindAn "assertion" that peeks at the string to the left of the current match location.
LooksmartCompany originally launched as a directory service which later morphed into a paid search provider and vertical content play. See also: Looksmart.com
lookup tableA special tabular data file containing additional attributes for features stored in an associated feature attribute table.
loopA construct that performs something repeatedly, like a roller coaster.
loop closureA condition in which the network presents a low-resistance tip-to-ring dc path at the network interface (NI). [T1.407-1990]
loop compensation lossThe loss that could be provided by a digital loop carrier system or a fiber-in-the-loop system when a short customer analog access cable results in…
loop control statementAny statement within the body of a loop that can make a loop prematurely stop looping or skip an "iteration".
loop filterIn a phase-locked loop, a filter located between the phase detector (or time discriminator) and the voltage controlled oscillator (or phase shifter).
loop gainThe total usable power gain of a carrier terminal or two-wire repeater. Note: The maximum usable gain is determined by, and may not exceed, the losses in…
loop labelA kind of key or name attached to a loop (or roller coaster) so that loop control statements can talk about which loop they want to control.
loop noiseThe noise contributed by one or both loops of a telephone circuit to the total circuit noise.
loop openA signal in which the network applies a high resistance between the tip and ring conductors at the network interface (NI). [T1.407-1997]
loop startA supervisory signal given by a telephone or PBX in response to completing the loop path.
loop testA test that uses a closed circuit, i.e., loop, to detect and locate faults.
loop transmissionMultipoint transmission in which (a) all the stations in a network are serially connected in one closed loop, (b) there are no cross-connections, (c) the…
loop variableA variable used to control the operation of a loop, such as a for loop. Typically, a loop variable will be given an initial value and it is then…
loop-backA method of performing transmission tests of access lines from the serving switching center, which method usually does not require the assistance of…
looped dual busA distributed-queue dual-bus (DQDB) scheme in which the head-of-bus functions for both buses are at the same location.
LoranLong Range Navigation, a system of long range navigation whereby latitude and longitude are determined from the time displacement of radio signals from…
loran stationA long distance radionavigation land station transmitting synchronized pulses. Hyperbolic lines of position are determined by the measurement of the…
LossThe amount an insurance company pays on a claim.
Loss DeviationThe term "Loss Deviation" denotes the variation of the actual loss from the designed value.
lossless compressionExact construction of image, bit-by-bit, with no loss of information.
lossy compressionReduces storage size of image by reducing the resolution and color fidelity while maintaining minimum acceptable standard for general use.
lossy failoverAn unscheduled outage of a clustered mailbox server (CMS) in a cluster continuous cluster (CCR) environment in which data was lost. [Exchange 2007]
lossy mediumA medium in which a significant amount of the energy of a propagating electromagnetic wave is absorbed per unit distance traveled by the wave. [After 2196]
lost blockA block not delivered to the user within a specified maximum end-to-end block transfer time.