23-letter words containing d, r
- brinell hardness number — a measure of the hardness of a material obtained by pressing a hard steel ball into its surface; it is expressed as the ratio of the load on the ball in kilograms to the area of the depression made by the ball in square millimetres
- british and irish lions — a touring rugby union side composed of players invited from England, Scotland, Wales, and Ireland
- broadcast quality video — (communications, multimedia) Roughly, video with more than 30 frames per second at a resolution of 800 x 640 pixels. The quality of moving pictures and sound is determined by the complete chain from camera to receiver. Relevant factors are the colour temperature of the lighting, the balance of the red, green and blue vision pick-up tubes to produce the correct display colour temperature (which will be different) and the gamma pre-correction to cancel the non-linear characteristic of cathode-ray tubes in television receivers. The resolution of the camera tube and video coding system will determine the maximum number of pixels in the picture. Different colour coding systems have different defects. The NTSC system (National Television Systems Committee) can produce hue errors. The PAL system (Phase Alternation by Line) can produce saturation errors. Television modulation systems are specified by ITU CCIR Report 624. Low-resolution systems have bandwidths of 4.2 MHz with 525 to 625 lines per frame as used in the Americas and Japan. Medium resolution of 5 to 6.5 MHz with 625 lines is used in Europe, Asia, Africa and Australasia. High-Definition Television (HDTV) will require 8 MHz or more of bandwidth. A medium resolution (5.5 MHz in UK) picture can be represented by 572 lines of 402 pixels. Note the ratio of pixels to lines is not the same as the aspect ratio. A VGA display (480n lines of 640 pixels) could thus display 84% of the height of one picture frame. Most compression techniques reduce quality as they assume a restricted range of detail and motion and discard details to which the human eye is not sensitive. Broadcast quality implies something better than amateur or domestic video and therefore can't be retained on a domestic video recorder. Broadcasts use quadriplex or U-matic recorders. The lowest frame rate used for commercial entertainment is the 24Hz of the 35mm cinema camera. When broadcast on a 50Hz television system, the pictures are screened at 25Hz reducing the running times by 4%. On a 60Hz system every five movie frames are screened as six TV frames, still at the 4% increased rate. The six frames are made by mixing adjacent frames, with some degradation of the picture. A computer system to meet international standard reproduction would at least VGA resolution, an interlaced frame rate of 24Hz and 8 bits to represent the luminance (Y) component. For a component display system using red, green and blue (RGB) electron guns and phosphor dots each will require 7 bits. Transmission and recording is different as various coding schemes need less bits if other representations are used instead of RGB. Broadcasts use YUV and compression can reduce this to about 3.5 bits per pixel without perceptible degradation. High-quality video and sound can be carried on a 34 Mbaud channel after being compressed with ADPCM and variable length coding, potentially in real time.
- business administration — a program of studies at a college or university covering finance, management of personnel, etc., designed to prepare a person for a career in business
- cachoeiro do itapemirim — a city in SE Brazil.
- calorie-controlled diet — a diet that restricts a person to a limited number of calories per day
- camillo benso di cavour — Camillo Benso di [kah-meel-law ben-saw dee] /kɑˈmil lɔ ˈbɛn sɔ di/ (Show IPA), 1810–61, Italian statesman: leader in the unification of Italy.
- castellammare di stabia — a port and resort in SW Italy, in Campania on the Bay of Naples: site of the Roman resort of Stabiae, which was destroyed by the eruption of Vesuvius in 79 ad. Pop: 66 929 (2001)
- catch someone off guard — If someone catches you off guard, they surprise you by doing something you do not expect. If something catches you off guard, it surprises you by happening when you are not expecting it.
- catherine of alexandria — Saint, a.d. c310, Christian martyr.
- chi-square distribution — a continuous single-parameter distribution derived as a special case of the gamma distribution and used esp to measure goodness of fit and to test hypotheses and obtain confidence intervals for the variance of a normally distributed variable
- chief education officer — an official who is the chief administrative officer of a Local Education Authority
- chorionic gonadotrophin — a hormone secreted by the chorionic villi of the placenta in mammals, esp human chorionic gonadotrophin. It promotes the secretion of progesterone by the corpus luteum and its presence in the urine is an indication of pregnancy
- chronic wasting disease — a disease found among members of the deer family, a type of transmissible spongiform encephalopathy
- circumstantial evidence — indirect evidence that tends to establish a conclusion by inference
- citizens' advice bureau — an independent charity where the public can obtain free, confidential information and advice on an extensive range of civil, consumer, and legal matters
- citrus greening disease — Plant Pathology. a bacterial disease of citrus trees, transmitted by insects of the Psyllidae family.
- civil aeronautics board — the former federal agency (1938–85) that regulated airline fares and assigned routes. Abbreviation: CAB, C.A.B.
- client-centered therapy — a nondirective method of psychotherapy in which treatment consists of helping patients to use effectively their own latent resources in solving problems.
- collision damage waiver — a form of optional collision insurance cover for a vehicle that is being rented
- communication breakdown — a lack of communication; a failure to exchange information
- community-service order — (in Britain) a court order requiring an offender over seventeen years old to do unpaid socially beneficial work under supervision instead of going to prison
- compact disc read-write — Compact Disc Rewritable
- compact disc recordable — (storage) (CD-R) A write-once version of CD-ROM. CD-Rs can hold about 650 megabytes of data. They are very durable and can be read by normal CD-ROM drives, but once data has been written it cannot be altered. Standard prerecorded CDs have their information permanently stamped into an aluminium reflecting layer. CD-R discs have a dye-based recording layer and an additional golden reflecting layer. Digital information is written to the disc by burning (forming) pits in the recording layer in a pattern corresponding to that of a conventional CD. The laser beam heats the substrate and recording layer to approximately 250 C. The recording layer melts and the substrate expands into the space that becomes available. See also CD-RW and DVD-RAM.
- compact disc rewritable — (storage) (CD-RW) A rewritable version of CD-ROM. A CD-RW drive can write about 650 megabytes of data to CD-RW media an unlimited number of times. Most CD-RW drives can also write once to CD-R media. CD-RW media cannot be read by CD-ROM drives built prior to 1997 due to the reduced reflectivity (15% compared to 70%) of CD-RW media. CD-RW drives and media are currently (1999) more expensive than CD-R drives and media. CD-R is sometimes considered a better technology for archival purposes as the data cannot be accidentally modified or tampered with, and encourages better archival practices. Standard prerecorded CDs have their information permanently stamped into an aluminium reflecting layer. CD-WR discs have a phase-change recording layer and an additional silver (aluminium) reflecting layer. A laser beam can melt crystals in the recording layer into a non-crystalline amorphous phase or anneal them slowly at a lower temperature back to the crystalline state. The different reflectance of the areas make them appear as the 'pits' and 'lands' of a standard CD. See also CD-R and DVD-RAM.
- comparative advertising — a form of advertising in which a product is compared favourably with similar products on the market
- computer-aided learning — Computer-Aided Instruction
- computer-based training — Computer-Aided Instruction
- computerized tomography — a radiological technique that produces images of cross sections through a patient's body using low levels of radiation
- concrete data structure — (theory) (CDS) A model of programming language terms developed in the context of constructing fully abstract semantics for sequential languages. A CDS is a 4-tuple (C,V,E,|-) where C is a cell, V is a value, E is an event and |- is an "enabling relation". An event is a cell and a value. A cell C is "enabled" by a set of events S if S |- C. A state is a set of events which are consistent in that the values they give for any cell are all equal. Every cell in a state is enabled.
- condition code register — a hardware register used for storing the current values of the condition codes
- conditional convergence — the property of an infinite series that converges while the series formed by replacing each term in the given series with its absolute value diverges; the property of an infinite series that converges when the order of the terms is altered. Compare absolute convergence (def 1).
- conditional probability — the probability of one event, A, occurring given that another, B, is already known to have occurred: written P(A|B) and equal to P(A and B)|P(B)
- conditioned suppression — the reduction in the frequency of a learned response, e.g. pressing a bar for water, that occurs when a stimulus previously associated with pain is present
- consolidated deliveries — deliveries of goods to different shops in a common location by a single carrier and in a single vehicle
- constructive cost model — (programming) (COCOMO) A method for estimating the cost of a software package, proposed by Dr Barry Boehm. The Basic COCOMO Model estimates the effort required to develop software in three modes of development (Organic Mode, Semidetached Mode, or Embedded Mode) using only DSIs as an input. The Basic model is good for quick estimates. The Intermediate Model extends the Basic Model with an Effort Adjustment Factor (EAF) and different coefficients for the effort equation. The user supplies settings for cost drivers that determine the effort and duration of the software projects. It also allows DSI values and cost drivers to be chosen for individual components instead of for the system as a whole. The Detailed COCOMO Model uses effort multipliers for each phase of the project and provides a three-level product hierarchy and has some other capabilities such as a procedure for adjusting the phase distribution of the development schedule.
- cordillera de talamanca — a mountain range running SE from central Costa Rica to W Panama.
- corridor of uncertainty — an area of a wicket just outside a batsman's off stump, so located that the batsman will have difficulty in deciding whether or not to play a ball bowled into it
- credit-reference agency — an agency, other than a bank, that specializes in providing credit ratings of people or organizations
- criminal records bureau — (in England and Wales) a service offering employers and voluntary organizations access to police, health, and education records
- cut sb's umbilical cord — If you say that one person, organization, or country has cut its umbilical cord with another, you mean that they have done something that makes them more independent.
- cyclic redundancy check — (algorithm) (CRC or "cyclic redundancy code") A number derived from, and stored or transmitted with, a block of data in order to detect corruption. By recalculating the CRC and comparing it to the value originally transmitted, the receiver can detect some types of transmission errors. A CRC is more complicated than a checksum. It is calculated using division either using shifts and exclusive ORs or table lookup (modulo 256 or 65536). The CRC is "redundant" in that it adds no information. A single corrupted bit in the data will result in a one bit change in the calculated CRC but multiple corrupted bits may cancel each other out. CRCs treat blocks of input bits as coefficient-sets for polynomials. E.g., binary 10100000 implies the polynomial: 1*x^7 + 0*x^6 + 1*x^5 + 0*x^4 + 0*x^3 + 0*x^2 + 0*x^1 + 0*x^0. This is the "message polynomial". A second polynomial, with constant coefficients, is called the "generator polynomial". This is divided into the message polynomial, giving a quotient and remainder. The coefficients of the remainder form the bits of the final CRC. So, an order-33 generator polynomial is necessary to generate a 32-bit CRC. The exact bit-set used for the generator polynomial will naturally affect the CRC that is computed. Most CRC implementations seem to operate 8 bits at a time by building a table of 256 entries, representing all 256 possible 8-bit byte combinations, and determining the effect that each byte will have. CRCs are then computed using an input byte to select a 16- or 32-bit value from the table. This value is then used to update the CRC.
- cylinder vacuum cleaner — a type of vacuum cleaner in which dirt, dust, etc, is sucked into a hard cylinder rather than a bag
- cylindrical coordinates — three coordinates defining the location of a point in three-dimensional space in terms of its polar coordinates (r, θ) in one plane, usually the (x, y) plane, and its perpendicular distance, z, measured from this plane
- d'arsonval galvanometer — a galvanometer consisting of a large, fixed magnet and a light coil that swings in the magnetic field.
- d'entrecasteaux islands — a group of volcanic islands in the Pacific, off the SE coast of New Guinea: part of Papua New Guinea. Pop: 49 167 (1990 est). Area: 3141 sq km (1213 sq miles)
- dacryocystorhinostomies — Plural form of dacryocystorhinostomy.
- dark-field illumination — illumination of the field of a microscope from the side so that the specimen is viewed against a dark background
- data terminal equipment — (communications, hardware) (DTE) A device which acts as the source and/or destination of data and which controls the communication channel. DTE includes terminals, computers, protocol converters, and multiplexors. DTE is usually connected via an EIA-232 serial line to Data Communication Equipment (DCE), typically a modem. It is necessary to distinguish these two types of device because their connectors must be wired differently if a "straight-through" cable (pin 1 to pin 1, pin 2 to pin 2 etc.) is to be used. DTE should have a male connector and should transmit on pin three and receive on pin two. It is a curious fact that many modems are actually "DTE" according to the original standard.
- database query language — (database) A language in which users of a database can (interactively) formulate requests and generate reports. The best known is SQL.