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characteristic curve
characteristic curve n (Photography) photog a graph of the density of a particular photographic material plotted against the logarithm of the exposure producing this density ThesaurusNoun | 1. | characteristic curve - (electronics) graph showing how a particular characteristic of a device varies with other parameterscharacterisic functionelectronics - the branch of physics that deals with the emission and effects of electrons and with the use of electronic devicesgraph, graphical record - a visual representation of the relations between certain quantities plotted with reference to a set of axesfrequency-response characteristic, frequency-response curve - (electronics) a graph of frequency response with signal amplitude or gain plotted against frequency | TranslationsCharacteristic Curve
characteristic curve[‚kar·ik·tə′ris·tik ′kərv] (graphic arts) In photography, a graph that shows how increases in exposure increase the density of the film. (mathematics) One of a pair of conjugate curves in a surface with the property that the directions of the tangents through any point of the curve are the characteristic directions of the surface. A curve plotted on graph paper to show the relation between two changing values. A characteristic curve of a one-parameter family of surfaces is the limit of the curve of intersection of two neighboring surfaces of the family as those surfaces approach coincidence. Characteristic Curve one of the most important indexes of a photographic material. It expresses (for specified exposure and developing conditions) the optical density obtained from photographic darkening of the material as a function of the common logarithm of the exposure that produced the darkening. (SeeSENSITOMETRY.) Characteristic curve A graphical display depicting complex nonlinear relationships in electronic circuits. A typical use is to show voltage-current relationships in semiconductor devices. Device amplification capabilities, for example, are exhibited by a characteristic plot which traces output current versus output voltage with a third controlling variable as a parameter. This control variable could be the base current of a bipolar junction transistor (BJT) or the gate-to-source voltage of a metal-oxide-semiconductor (MOS) transistor. Other characteristics often included in transistor data sheets are displays of current gain versus bias current, gain versus frequency, and input and output impedances versus frequency. Less commonly, other graphical nonlinear relationships, such as the variation of thermocouple voltage with temperature or the dependence of electrical motor torque with current, also are known as characteristic curves. In the past, characteristic curves were used as tools in the graphical solution of nonlinear circuit equations that are followed by relationships of this type. In current practice, this analysis is performed using computer packages for circuit simulation. Designers still use characteristic curves from data sheets, however, to evaluate relative performance capabilities when selecting devices, and to provide the information needed for a preliminary pencil-and-paper circuit design. See Amplifier, Transistor characteristic curve
char·ac·ter·is·tic curvesensitometric curve of radiographic film, a plot of the film density versus the logarithm of the relative exposure. Synonym(s): H and D curve, Hunter and Driffield curvecurve (kurv) [L. curvus, bent, crooked] A bend, chart, or graph.bell curveNormal distribution.curve of Carus See: curve of Caruscharacteristic curveSensitometric curve.dental curveCurve of Spee.D log E curveSensitometric curve.dose response curveA graph charting the effect of a specific dose of drug, chemical, or ionizing radiation.dye-dilution curveA graph of the disappearance rate of a known amount of injected dye from the circulation; used to measure cardiac function. epidemic curveA chart or graph in which the number of new cases of an illness is plotted over time.Gaussian curveNormal distribution.growth curveA graph of heights and weights, head circumference, and body mass index of infants and children of various ages. A line connecting the data points produces the curve. Usually the changes in height and weight are shown on the same chart. Growth charts are specific for age and gender. learning curveThe effect of learning or practice on the performance of an intellectual or physical task. The term describes the acquisition of competence with experience, time, and training. normal curveNormal distribution.receiver operating curve Abbreviation: ROC curve A plot of the fraction of true positives test results versus the fraction of false positive test results; the sensitivity of a test versus (1-the test specificity). Synonym: receiver operating characteristicsensitometric curveIn radiographic film analysis, the curve derived by graphing the exposure to the film versus the film density. Analysis yields information about the contrast, speed, latitude, and maximum and minimum densities of the film or film-screen system. Digital radiography systems exhibit linear curves. Synonym: characteristic curve; D log E curve; Hurter and Driffield curvecurve of Spee See: curve of SpeeStephan curve See: Stephan curvesurvival curveIn radiobiology, a dose response curve. time-temperature cooling curveThe mathematical relation that plots the physical and chemical behaviors of dental (and other) materials as their temperature decreases over time.characteristic curve
Synonyms for characteristic curvenoun (electronics) graph showing how a particular characteristic of a device varies with other parametersSynonymsRelated Words- electronics
- graph
- graphical record
- frequency-response characteristic
- frequency-response curve
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