Error of indication

There are problems to be considered and avoided when using Hquid-in-glass thermometers. One type of these is pressure errors. The change in height of the mercury column is a function of the volume of the bulb compared to the volume of the capillary. An external pressure (positive or negative) which tends to alter the bulb volume causes an error of indication, which may be small for normal barometric pressure variations but large when, for example, using the thermometer in an autoclave or pressure vessel. 

The bias error is a quantity that gives the total systematic error of a measuring instrument under defined conditions. As mentioned earlier, the bias should be minimized by calibration. The repeatability error consists of the confidence limits of a single measurement under certain conditions. The mac-curacy or error of indication is the total error of the instrument, including the... 

The dipstick test for total protein includes a cellulose test pad impregnated with tetrabromphenol blue and a citrate pH 3 buffer. The reaction is based on the protein error of indicators phenomenon in which certain chemical indicators demonstrate one color in the presence of protein and another in its absence. Thus tetrabromphenol blue is green in the presence of protem at pH 3 but yellow in its absence. The color is read after exactly 60s and the test has a lower detection limit of 150 to 300mg/L, depending on the type and proportions of protein present. The reagent is most sensitive to albumin and less sensitive to globulins, Bence Jones protein, mucoproteins, and hemoglobin. 

The acid-base error of indicators. Isohydric indicators. The measurement of pH in unbuffered or slightly buffered solutions. 

Whereas the acid or base error of indicators can be eliminated by proper experimental conditions, the influence of electrolytes can not be avoided experimentally. The effect of electrolytes can be traced in general to two causes ... 

The first useful application of the protein error of indicators arose from the early studies of Klotz (K22, K23). In the presence of low concentrations of bovine albumin, but not of 7-globulin or gelatin, the absorption spectra of a number of different dye solutions have been found to undergo pronounced shifts. Albumin-binding data and absorption maxima of many anionic azo dyes have been listed (M3). Three of these dyes have been utilized for protein estimation. 

For a CMM standards like ISO 10360 (2000-2011), define some parameters that could be used for defining accuracy as a combination of systematic and random errors, like the error of indication of a CMM for size measurement, E, and the probing error, P. However, with these parameters only a very small application range of a CMM is covered the measurement of the distance between two nominally parallel planes approached from opposite directions and the measurement of a precision sphere. With these parameters we hardly can make a statement on accuracy of measurement of, for example, parallelism of bores and of squareness between planes. 

ERROR FLAG INDICATING FAILURE OF SUBROUTINE MULLER TO CONVERGE lUSED ONLY WHEN ORGANIC ACIDS PRESENT CNTRL VARIABLE... 

From tests with Level-2-inspectors [2, 3] we learn that 10 % of the errors in weld testing are caused hy too fast probe movements (indications are missed or overlooked), 34 % by too strong coupling variations (underestimation of indications) or coupling failures and 56 % by incomplete scanning (untested areas). 

Normal distribution curves showing the definition of detection limit and limit of identification (LOI). The probability of a type 1 error is indicated by the dark shading, and the probability of a type 2 error is indicated by light shading. 

Although the most sensitive line for cadmium in the arc or spark spectmm is at 228.8 nm, the line at 326.1 nm is more convenient to use for spectroscopic detection. The limit of detection at this wavelength amounts to 0.001% cadmium with ordinary techniques and 0.00001% using specialized methods. Determination in concentrations up to 10% is accompHshed by solubilization of the sample followed by atomic absorption measurement. The range can be extended to still higher cadmium levels provided that a relative error of 0.5% is acceptable. Another quantitative analysis method is by titration at pH 10 with a standard solution of ethylenediarninetetraacetic acid (EDTA) and Eriochrome Black T indicator. Zinc interferes and therefore must first be removed. 

The effect of pulsating flow on pitot-tube accuracy is treated by Ower et al., op. cit., pp. 310-312. For sinusoidal velocity fluctuations, the ratio of indicated velocity to actual mean velocity is given by the factor /l + AV2, where X is the velocity excursion as a fraction of the mean velocity. Thus, the indicated velocity would be about 6 percent high for velocity fluctuations of 50 percent, and pulsations greater than 20 percent should be damped to avoid errors greater than 1 percent. Tne error increases as the frequency of flow oscillations approaches the natural frequency of the pitot tube and the density of the measuring fluid approaches the density of the process fluid [see Horlock and Daneshyar, y. Mech. Eng. Sci, 15, 144-152 (1973)]. 

The threshold for the current comparator is set by the output of the voltage error amplifier. If the voltage error amplifier indicates that the output voltage is too low, then the current threshold is raised to allow more energy to reach the load. The converse is true too. 

Figure 9.13 indicates the burner temperature time response The temperature falls from its initial value, since the gas valve is closed, and then climbs with a response indicated by the eigenvalues in equation (9.93) to a steady-state value of 400 °C, or a steady-state error of 50 °C. 

Human operator errors are not usually examined in a FMEA, but the effects of human error are indicated by the equipment failure mode. FMEAs rarely investigate damage or injury that could arise if the system or process operated successfully. Because FMEAs focus on single event failures, they are not efficient for identifying an exhaustive list of combinations of equipment failures iliat iead to accidents. 

The lighter arrows represent typical shortcuts, which omit particular stages in the information-processing chain. These shortcuts may be "legitimate," and would only lead to errors in certain cases. For example, the worker may erroneously believe that he or she recognizes a pattern of indicators and may immediately execute a skill-based response, instead of moving to the rule-based level to apply an explicit diagnostic rule. 

To avoid the errors of polarisation and stray currents, special resistivity meters are employed. One form of these uses an alternating current produced from batteries by a vibrator. The effective resistance is measured by a modified Wheatstone bridge with balance indicated by a galvanometer. 

FIGURE 11.2 Paired experimental data. Values of constitutive calcitonin receptor activity [1 -(Tr/Tj) units] in transiently transfected melanophores. Five separate experiments are shown. Points to the left indicate the basal level of constitutive activity before (filled circles) and after (open circles) addition of 100 nM AC512 (calcitonin receptor inverse agonist). Lines join values for each individual experiment. Points to the right are the mean values for constitutive activity in control (filled circles) and after AC512 (open circles) for all five experiments (bars represent standard errors of the mean). Data shown in Table 11.3. 

EDTA is a very unselective reagent because it complexes with numerous doubly, triply and quadruply charged cations. When a solution containing two cations which complex with EDTA is titrated without the addition of a complex-forming indicator, and if a titration error of 0.1 per cent is permissible, then the ratio of the stability constants of the EDTA complexes of the two metals M and N must be such that KM/KN 106 if N is not to interfere with the titration of M. Strictly, of course, the constants KM and KN considered in the above expression should be the apparent stability constants of the complexes. If complex-forming indicators are used, then for a similar titration error KM/KN z 108. 

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