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Measures criterion

The measurability criterion used by the FDA is a reasonable, conservative, and compromise criterion because although radioactivity is known in principle to be produced at energies below 10 m.e.v., such radioactivity has not only been nonmeasurable in food samples but also is probably not radio-logically significant. The criterion also simplifies control of the process considerably and eliminates the need for on-line monitoring of radioactivity induced by the process. [Pg.96]

Whenever this kind of activity becomes part of the manufacturing plan, the benefits of the setup-dominant process will be realized. This results because the quality standard, formed by the development function in the performance qualification, is carried over to the production setting. When production then incorporates this standard into its own operating procedures, the quality standard becomes a measurable criterion for performance. This example thus clearly shows how this phase of PV would be a QA tool for auditing. [Pg.790]

As mentioned in Section 1.2.3, the measurement of Tice can also be used as a quantitatively measurable criterion to terminate MD and change to SD. Figure 2.90 summarizes the T. data for six different mns with 10% saccharose solution, d = 10 mm, pc = 0.15 mbar. The different parameters are number of vials, freezing rate, Tsh, time elapsed between end of freezing and start of drying. [Pg.276]

Audit instruments can be evaluated on the basis of three different types of validity when linking the audit to safety performance. These are content-related, criterion-related, and construct-related procedures for accumulating evidence of validity (Anastasi 1988, 139). Content-related validity involves the examination of the audit content to determine whether it covers a representative sample of the behaviors to be measured. Criterion-related validity procedures indicate the effectiveness of an audit in predicting performance in specified activities. The performance on the audit is checked against a criterion that is considered a direct and independent measure of what the audit was intended to measure. The third type of validity, construct validity, is the extent to which the audit is said to be measuring a theoretical construct or trait. Construct validation requires accumulation of information from a variety of sources. [Pg.108]

The most reliable estimates of the parameters are obtained from multiple measurements, usually a series of vapor-liquid equilibrium data (T, P, x and y). Because the number of data points exceeds the number of parameters to be estimated, the equilibrium equations are not exactly satisfied for all experimental measurements. Exact agreement between the model and experiment is not achieved due to random and systematic errors in the data and due to inadequacies of the model. The optimum parameters should, therefore, be found by satisfaction of some selected statistical criterion, as discussed in Chapter 6. However, regardless of statistical sophistication, there is no substitute for reliable experimental data. [Pg.44]

If this criterion is based on the maximum-likelihood principle, it leads to those parameter values that make the experimental observations appear most likely when taken as a whole. The likelihood function is defined as the joint probability of the observed values of the variables for any set of true values of the variables, model parameters, and error variances. The best estimates of the model parameters and of the true values of the measured variables are those which maximize this likelihood function with a normal distribution assumed for the experimental errors. [Pg.98]

The criterion retained up to now in the specifications is not the true vapor pressure, but an associated value called the Reid vapor pressure, RVP. The procedure is to measure the relative pressure developed by the vapors from a sample of motor fuel put in a metallic cylinder at a temperature of 37.8°C. The variations characteristic of the standard method are around 15 millibar in repeatability and 25 millibar in reproducibility. [Pg.189]

To estimate the quality of restoration having both, simulated and reconstructed images, using some kind of quality criterion For this last purpose the following mean square measure was applied ... [Pg.117]

In many cases, the methods used to solve identification problems are based on an iterative minimization of some performance criterion measuring the dissimilarity between the experimental and the synthetic data (generated by the current estimate of the direct model). In our case, direct quantitative comparison of two Bscan images at the pixels level is a very difficult task and involves the solution of a very difficult optimization problem, which can be also ill-behaved. Moreover, it would lead to a tremendous amount of computational burden. Segmented Bscan images may be used as concentrated representations of the useful... [Pg.172]

This method is exemplified by its application to quinoline, isoquinoline, cinnoline, and isoquinoline 2-oxide, which are nitrated as their conjugate acids. The rate profiles for these compounds and their N- or O-methyl perchlorates show closely parallel dependences upon acidity (fig. 2.4). Quaternisation had in each case only a small effect upon the rate, making the criterion a very reliable one. It has the additional advantage of being applicable at any temperature for which kinetic measurements can be made (table 8.1, sections B and D). [Pg.153]

Measurement Requirements. Any analysis of measurement requirements must begin with consideration of the particular accuracy, repeatabihty, and range needed. Depending on the appHcation, other measurement considerations might be the speed of system response and the pressure drop across the flow meter. For control appHcations repeatabihty may be the principal criterion conversely for critical measurements, the total installed system accuracy should be considered. This latter includes the accuracy of the flow meter and associated readout devices as well as the effects of piping, temperature, pressure, and fluid density. The accuracy of the system may also relate to the required measurement range. [Pg.56]

Loss of elongation is the most sensitive criterion for aging measurement regardless of mechanism, and it is favored over measurement of tensile loss for cured compounds. In synthetic mbber production (SBR, in particular), viscosity increases with aging and can affect processing if not prevented. [Pg.246]

The hardness of a mineral as measured by the Mohs scale is a criterion of its resistance to crushing [Fahrenwald, Trans. Am. In.st. Min. Metall. Pet. Eng., 112, 88 (1934)]. It is a fairly good indication of the abrasive character of the mineral, a factor that determines the wear on the grinding media. Arranged in increasing order or hardness, the Mohs scale is as fohows 1, talc 2, gypsum 3, calcite 4, fluoride 5, apatite 6, feldspar 7, quartz 8, topaz 9, corundum and 10, diamond. [Pg.1829]

Until Jenike developed the rationale for storage-vessel design, a common criterion was to measure the angle of repose, use this value as the hopper angle, and then fit the bin to whatever space was available. Too often, bins were designed from an architectural or structural-engineering viewpoint rather than from the role they were to play in a process. Economy of space is certainly one vahd criterion in bin design, but others must be considered equally as well. Table 21-14 compares the principal characteristics of mass-flow and funnel-flow bins. [Pg.1935]

The statistics literature presents numerous reviews of comparing the description of one model against another. Watanabe and Himmel-blau (1984) present a list of review articles. The judgment criterion is based on a comparison of the model predictions against the measurements. These comparisons are related to the general statistic given below, developed tor each model with its corresponding parameter set. [Pg.2578]

A typical screwdriver has a shaft and blade made of a high-carbon steel, a metal. Steel is chosen because its modulus is high. The modulus measures the resistance of the material to elastic deflection or bending. If you made the shaft out of a polymer like polyethylene instead, it would twist far too much. A high modulus is one criterion in... [Pg.3]

Criteria 2 to 6 are pragmatic criteria which are only applicable to qualitative explanations. These criteria only give qualitative information which is dealt with further below (Section 3.3.3.1). Criterion 7 gives better information with potential test probes (see Section 3.3.3.2). In all the criteria it must be remembered that only mixed potentials can be measured for extended objects to be protected [see the explanation to Eqs. (3-19) and (3-28)]. Criteria 5 and 6 are particularly to be observed for objects [22]. A comparison of the different criteria in field experiments has shown that, besides Criterion 1, good results are obtained with Criterion 3 [26]. [Pg.103]


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