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Inadequacy

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]

The numerical illustration given above is so highly idealized that any agreement with experiment could hardly be more than coincidental. A number of caveats have been mentioned, including the inadequacies of theoretical calculations, the various surface distortions and reconstructions expected, surface... [Pg.271]

Claverie P 1971 Theory of intermolecular forces. I. On the inadequacy of the usual Rayleigh-Schrddinger perturbation method for the treatment of intermolecular forces Int. J. Quantum Chem. 5 273... [Pg.213]

Benzene has already been mentioned as a prime example of the inadequacy of a connection table description, as it cannot adequately be represented by a single valence bond structure. Consequently, whenever some property of an arbitrary molecule is accessed which is influenced by conjugation, the other possible resonance structures have to be at least generated and weighted. Attempts have already been made to derive adequate representations of r-electron systems [84, 85]. [Pg.65]

Basically, Newtonian mechanics worked well for problems involving terrestrial and even celestial bodies, providing rational and quantifiable relationships between mass, velocity, acceleration, and force. However, in the realm of optics and electricity, numerous observations seemed to defy Newtonian laws. Phenomena such as diffraction and interference could only be explained if light had both particle and wave properties. Indeed, particles such as electrons and x-rays appeared to have both discrete energy states and momentum, properties similar to those of light. None of the classical, or Newtonian, laws could account for such behavior, and such inadequacies led scientists to search for new concepts in the consideration of the nature of reahty. [Pg.161]

At least three types of citations in patents can be identified inventors citations found in the patent specification, examiners citations found on issued U.S. patents, and examiners citations found on pubHshed appHcations and granted patents from other countries. A patent inventor cites prior art in order to distance the invention from that art, rather than to show a close relationship. Whereas scientific researchers may want to show how closely they have built on what went before, for an inventor that can suggest anticipation or at least obviousness. Thus, citations within a patent typicaHy try to demonstrate the inadequacies of prior inventions and the uniqueness of the patentee s own work. References tied by this type of citation can be usefiil in developing a picture of the state of the art, but often show sharply differing technologies. [Pg.58]

Experimentally deterrnined equiUbrium constants are usually calculated from concentrations rather than from the activities of the species involved. Thermodynamic constants, based on ion activities, require activity coefficients. Because of the inadequacy of present theory for either calculating or determining activity coefficients for the compHcated ionic stmctures involved, the relatively few known thermodynamic constants have usually been obtained by extrapolation of results to infinite dilution. The constants based on concentration have usually been deterrnined in dilute solution in the presence of excess inert ions to maintain constant ionic strength. Thus concentration constants are accurate only under conditions reasonably close to those used for their deterrnination. Beyond these conditions, concentration constants may be useful in estimating probable effects and relative behaviors, and chelation process designers need to make allowances for these differences in conditions. [Pg.385]

This section seeks to summarize preferred routes to various types of pyrimidine. To some extent it is based on the personal experience of the present author, who is well aware of its resulting inadequacies. [Pg.123]

Equation (9-234) illustrates the enormous influence that go-slow tactics can have on the profitability of companies and processes which have low contribution efficiencies, since a slowdown has little effect on Aee- B L sometimes the case that in different countries productivity per worker varies considerably in similar industries. When poor productivity is not the result of technical or capital inadequacy, it should be possible to increase profitability without a proportionate increase in Aee-... [Pg.860]

The presented results allow an understanding of the effect of inadequacy organic matrix of plant reference standai ds and dried milk on XRF result exactness. In the absence of similar RSMs calibrations, obtained with the help of plant RSMs, may be used for analysis of only non-fat milk powders. Correction on fat content will allow a spreading these calibrations on analysis of milk powders with any fat contents. [Pg.224]

Although the inadequacy of the one-dimensional model [Goldanskii 1959, 1979] is well by now understood, we start with discussing the simplest one-dimensional version of the theory, since it... [Pg.11]

The inadequacy of the worst case model is evident and the statistical nature of the tolerance stack is more realistic, especially when including the effects of shifted distributions. This has also been the conclusion of some of the literature discussing tolerance stack models (Chase and Parkinson, 1991 Harry and Stewart, 1988 Wu et al., 1988). Shifting and drifting of component distributions has been said to be the chief reason for the apparent disenchantment with statistical tolerancing in manufacturing (Evans, 1975). Modern equipment is frequently composed of thousands of components, all of which interact within various tolerances. Failures often arise from a combination of drift conditions rather than the failure of a specific component. These are more difficult to predict and are therefore less likely to be foreseen by the designer (Smith, 1993). [Pg.130]

The inadequacy of the worst case approach to tolerance stack design compared to the statistical approach is evident, although it still appears to be popular with designers. The worst case tolerance stack model is inadequate and wasteful when the capability of each dimensional tolerance is high > 1.33). Some summarizing comments on the two main approaches are given below. [Pg.131]

As a final comment on inadequacies of mathematical representations of risk, those who bear the risk are not necessarily those who receive the benefit. While unequal distribution of risk and benefit may not be fair, it is difficult to redress die incquily. [Pg.8]

The inadequacy of these formulae became evident when the oxidation of tropine was studied. With potassium permanganate, in presence of acid, or with chromic acid, tropine and tropidine give rise to a series of oxidation products, the interrelationships of which are shown in the scheme on p. 75. [Pg.74]

Like VDA 6.1, AVSQ 94 does not include the requirements of ISO 9001. In this way issues of copyright are overcome, a practice shared by VDA and EAQF but not QS-9000. However, unlike VDA 6.1, AVSQ 94 follows the 20 elements of ISO 9001 with two additional elements, covering financial considerations and product safety. Those questions that go beyond ISO 9001 are marked and as every question is numbered it simplifies the evaluation process. A scoring method is employed to classify organizations in terms of a conformity index. Each question is awarded a point (0, 2.5, 5, 7.5, or 10), where 10 points means full compliance, 7.5 points means minor inadequacies, 5 points means inadequacies in application requiring improvement, 2.5 points means serious inadequacies in application, and 0 points is used for criteria not applied. Unfortunately all questions carry the same weight as no account of the impact of omission on product quality or customer satisfaction is included. [Pg.7]

The certification business has grown enormously in the last ten years. The International Accreditation Forum (lAF) recorded 616 accredited certification bodies in January 1999. The experience of the vehicle manufacturers with ISO 9000 certification led them to question the wisdom of so many certification bodies chasing the same business in a competitive market. The results seemed to indicate that cost reductions by the certification bodies led to a decline in the quality of auditing and that was the opposite of what the vehicle manufacturers wanted. The vehicle manufacturers had not seen a significant rise in product quality as a result of ISO 9000 and they believed this was partially due to the quality of the accreditation and certification schemes being operated as well as inadequacies in the quality system standard. When the four national automotive schemes were launched, great emphasis was placed on regulating more closely the accreditation and certification schemes. From a customer perspective, the ISO 10011 scheme had some particular problems ... [Pg.65]

Baldyga, J. and Bourne, J.R., 1984a. A fluid mechanical approach to turbulent mixing and chemical reaction. Part I Inadequacies of available methods. Chemical Engineering Communications, 28, 231-241. [Pg.300]

The preceding biaxial failure criteria suffer from various inadequacies in their representation of experimental data. One obvious way to improve the correlation between a criterion and experiment is to increase the number of terms in the prediction equation. This increase in curvefitting ability plus the added feature of representing the various strengths in tensor form was used by Tsai and Wu [2-26]. In the process, a new strength definition is required to represent the interaction between stresses in two directions. [Pg.114]

This classification underscores the inadequacy of the approach common in reliability engineering of simply classifying errors into omission and commission categories. [Pg.39]

Selecting the scope and location for the pilot project is important. The pilot must provide a realistic test for integration, without being unrealistically ambitious. The ideal subject for a pilot will have staff who are motivated to make integration work, yet have obvious inadequacies in their existing PSM and ESH management. [Pg.82]

Obviously for this method to work the ratio T1IT2 must be appreciably smaller than unity. Provided this condition is met, this method is a simple and reliable way to test for an isokinetic relationship or to detect deviations from such a relationship. Exner shows examples of systems plotted both as log 2 vs. log and as AH vs. A5, demonstrating the inadequacy of the latter plot. Exner has also developed a statistical analysis of the Petersen method this analysis yields p and an uncertainty estimate of p. Exner has applied his statistical methods to 100 reaction series, finding that 78 of them follow approximately valid isokinetic relationships. [Pg.370]

Wlien a practice drill shows inadequacies in performance of duties... [Pg.92]

Vitamin D is a family of closely related molecules that prevent rickets, a childhood disease characterized by inadequate intestinal absorption and kidney reabsorption of calcium and phosphate. These inadequacies eventually lead to the demineralization of bones. The symptoms of rickets include bowlegs,... [Pg.605]


See other pages where Inadequacy is mentioned: [Pg.2077]    [Pg.438]    [Pg.231]    [Pg.330]    [Pg.349]    [Pg.410]    [Pg.249]    [Pg.415]    [Pg.510]    [Pg.350]    [Pg.311]    [Pg.535]    [Pg.538]    [Pg.673]    [Pg.1829]    [Pg.36]    [Pg.416]    [Pg.59]    [Pg.365]    [Pg.176]    [Pg.323]    [Pg.258]    [Pg.193]    [Pg.100]    [Pg.88]    [Pg.345]    [Pg.523]   
See also in sourсe #XX -- [ Pg.123 , Pg.125 ]




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