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23-letter words containing r, o, t, i

  • 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
  • catherine of alexandria — Saint, a.d. c310, Christian martyr.
  • cauchy integral formula — a theorem that gives an expression in terms of an integral for the value of an analytic function at any point inside a simple closed curve of finite length in a domain.
  • cauchy integral theorem — the theorem that the integral of an analytic function about a closed curve of finite length in a finite, simply connected domain is zero.
  • caught in the crossfire — If you are caught in the crossfire, you become involved in an unpleasant situation in which people are arguing with each other, although you do not want to be involved or say which person you agree with.
  • center-pivot irrigation — a method of irrigation, used mainly in the western U.S., in which water is dispersed through a long, segmented arm that revolves about a deep well and covers a circular area from a quarter of a mile to a mile in diameter.
  • central processing unit — the part of a computer that performs logical and arithmetical operations on the data as specified in the instructions
  • certificate of registry — a document issued to a U.S. vessel engaged in foreign trade, stating its name, nationality, ownership, etc., and claiming for it all privileges pertaining to U.S. nationality.
  • character assassination — A character assassination is a deliberate attempt to destroy someone's reputation, especially by criticizing them in an unfair and dishonest way when they are not present.
  • characteristic equation — Mathematics. the characteristic polynomial of a given matrix, equated to zero. Also called auxiliary equation. an equation with one variable and equated to zero, which is derived from a given linear differential equation and in which the coefficient and power of the variable in each term correspond to the coefficient and order of a derivative in the original equation.
  • characteristic function — a function that assigns the value 1 to the members of a given set and the value 0 to its nonmembers
  • characteristic velocity — a measure of the effectiveness with which the combustion in a rocket engine produces high temperature and pressure, equal to the exhaust velocity divided by the thrust coefficient.
  • cheyne-stokes breathing — alternating shallow and deep breathing, as in comatose patients
  • 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
  • chief executive officer — The chief executive officer of a company is the person who has overall responsibility for the management of that company. The abbreviation CEO is often used.
  • chief operating officer — the executive in charge of day-to-day operations in an organization
  • chlorotrifluoroethylene — a colorless, flammable gas, C 2 H 2 ClF, that polymerizes to form oils, greases, and waxes.
  • 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
  • church of the subgenius — (body, humour)   A mutant offshoot of Discordianism launched in 1981 as a spoof of fundamentalist Christianity by the "Reverend" Ivan Stang, a brilliant satirist with a gift for promotion. Popular among hackers as a rich source of bizarre imagery and references such as "Bob" the divine drilling-equipment salesman, the Benevolent Space Xists, and the Stark Fist of Removal. Much SubGenius theory is concerned with the acquisition of the mystical substance or quality of slack.
  • civil aeronautics board — the former federal agency (1938–85) that regulated airline fares and assigned routes. Abbreviation: CAB, C.A.B.
  • coefficient of friction — the force required to move two sliding surfaces over each other, divided by the force holding them together. It is reduced once the motion has started
  • combinatorial chemistry — the use of chemical methods to generate all possible combinations of chemicals
  • come hell or high water — If you say that you will do something come hell or high water, you are emphasizing that you are determined to do it, in spite of the difficulties involved.
  • come with the territory — If you say that something comes with the territory, you mean that you accept it as a natural result of the situation you are in.
  • commercial exploitation — unethical business practices
  • communication breakdown — a lack of communication; a failure to exchange information
  • communication interface — an electronic circuit, usually designed to a specific standard, that enables one machine to telecommunicate with another machine
  • communications software — (communications, software)   Application programs, operating system components, and probably firmware, forming part of a communication system. These different software components might be classified according to the functions within the Open Systems Interconnect model which they provide. Typical applications include a web browser, Mail User Agent, chat and telnet.
  • communist international — Third International.
  • communist-international — an international organization (1919–43), founded in Moscow, uniting Communist groups of various countries and advocating the attainment of their ends by violent revolution. Also called Comintern, Communist International. Compare international (def 6).
  • community health centre — a medical centre that serves a particular area
  • 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
  • comparative linguistics — the study of the correspondences between languages that have a common origin.
  • composite colour signal — a colour television signal in which luminance and two chrominance components are encoded into a single signal
  • 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
  • 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
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