Raman scatteringThe generation of many different wavelengths of light from a nominally single-wavelength source (a) by means of lasing action and interaction with…
random access discrete address (RADA)A communications technique in which radio users share one wide frequency band instead of each user's being assigned a narrow band.
Random Access MemoryRandom access memory, or RAM, is memory whose contents are easily accessible to the processing components of a computer.
random access memory (RAM)A read/write, nonsequential-access memory used for the storage of instructions and data.
random dataData that are (a) unpredictable and have no discernable pattern, or (b) satisfy certain mathematical criteria for statistical randomness.
Random DefenseEngagement of RVs uniformly without any reference to type or destination. This implies taking the best shot possible in terms of increasing probability to…
random errorsErrors distributed over the signal in time so that they can be considered statistically independent from each other. [T1.226-1992]
random filingfiling of entities without regard to a particular order or pattern, used with an indexing system for locating them
random noiseNoise consisting of a large number of transient disturbances with a statistically random time distribution.
random numberA number selected from a known set of numbers in such a way that each number in the set has the same probability of occurrence. 2.
Random Number Generator (RNG)A process used to generate an unpredictable series of numbers. Each individual value is called random if each of the values in the total population of…
randomizerA device used to invert the sense of pseudorandomly selected bits of a bit stream to avoid long sequences of bits of the same sense.
RangeGeographic region in which a given plant or animal normally lives or grows.
range GETA range GET specifies a byte range of data to get for a download. If an object is large, you can break up a download into smaller units by sending…
Range ResolutionThe ability of the radar to distinguish two targets along the same radial but at different ranges. it is approximately ½ the pulse length.
Range restrictionsThe ability to limit a search to a specified range of a numerical metadata field. For example, a search for a digital camera between $250 and $400.
rangingThe measurement of the distance to a remote object (target), from a known observation or reference point.
RankThe numerical value of a card (as opposed to its suit). Example: "jack," "seven."
rank coercionThe ability to rank a file at the top of search results for a given search query. See also: property weighting
Rank profileA rank profile concept enables full control of the relative weight of each component for a given query (for example, how important an article's title is…
RankingRanking is a method of assigning a value to an investment in relation to comparable investments by using a scale.
Ranking modelsModels used to determine how closely content matches a particular query, and whether it should be included in the search results.
RAPTORA bird of prey such as a falcon, hawk, or eagle.
RAPTOR/TALONA technology demonstration program to demonstrate critical technologies for an unmanned airborne weapons system providing a boost phase intercept…
RARResource Adapter Archive. A JAR archive that contains a resource adapter module.
RARPReverse Address Resolution Protocol. A way of converting Ethernet addresses to IP addresses.
rasterA cellular data structure composed of rows and columns for storing images. Groups of cells with the same value represent features. See also grid.
raster countThe total number of raster scanning lines within a display space. [From Weik '89]
raster densityIn display systems, the number of scanning lines per unit distance perpendicular to the scanning direction. [From Weik '89]
raster scanningScanning in which the motion of the scanning spot follows a raster.
Rate AreaDenotes the smallest geographic area used to distinguish rate boundaries.
Rate CenterA geographically specified point used for determining mileage-dependent rates for PSTN calls. It is defined by a set of Vertical & Horizontal coordinates.
rated output powerThat power available at a specified output of a device under specified conditions of operation. Note: Rated output power may be further described; e.g.
RatingRating means evaluating a company, security, or investment product to determine how well it meets a specific set of objective criteria.
RationalizationAny action that increases the effectiveness of allied forces through more efficient or effective use of defense resources committed to the alliance.
rayA geometric representation of a lightwave by a line normal to the electromagnetic wavefront; i.e., in the direction of propagation of the wave. [FAA]
Rayleigh distributionA mathematical statement, usually applied to frequency distributions of random variables, for the case in which two orthogonal variables are independent…
Rayleigh fadingIn electromagnetic wave propagation, phase-interference fading caused by multipath, and which may be approximated by the Rayleigh distribution.
Rayleigh ScatteringChanges in directions of electromagnetic energy by particles whose diameters are 1/16 wavelength or less.
RBECSRevised Battlefield Electronic CEOI System (US Army-sponsored).
RBL (real-time block list)A database of Internet Protocol (IP) addresses of sources that have been verified as being unsolicited commercial e-mail (also known as spam).
RDM (Raw Device Mapping)A mechanism that enables a virtual machine to have direct access to a LUN on the physical storage subsystem (Fibre Channel or iSCSI only).
RDNSee definition for: Relative Distinguished Name (RDN)
RDT&E Program CategoriesThe five divisions the comprise Major Force Program 06 (R&D) in the FYDP. They are: • 6.1 Basic Research • 6.2 Exploratory Development • 6.
Re TargetingThe ability of the system to recomputed the direction of sensors and/or weapons to intercept a target that was missed on the first attempt, or that was…
Re-key (a certificate)To change the value of a cryptographic key that is being used in a cryptographic system application; this normally entails issuing a new certificate on…
Re-submissionRepeating the search engine registration process one or more times for the same page or site.
ReachAny specified length of stream, channel, or other water conveyance. A portion of a stream or a river.