Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Statistical limit

The essential assumption of all statistical theories is that during the long lifetime the total available energy is uniformly distributed among [Pg.250]


IMS Data Base, Intercontinental Medical Statistics Limited, Middlesex HA55HQ, UK. [Pg.477]

Ri does not show any phase transition. This should not be terribly surprising, since, in the deterministic limit, Ri exhibits either class 2 behavior (i.e. periodicity) or class 4 behavior (spatially separated propagating structures with an ill-defined statistical limit). The density p therefore has no well-defined statistical mean for p = 1 and the periodicity and/or propagating structures are rapidly destroyed (and thus p — 0) whenever p < 1. Moreover, from the above mean-field... [Pg.357]

In this example, data interpretations are based on g-statistic limits. These are computed by assuming the data are normally distributed in the multivariate sense. The diagnostic limits are used to establish when a statistically significant shift has occurred. Charts based on these statistics and used in this manner are analogous to conventional SPC charts. [Pg.87]

However, it has been pointed out 13 16> for large organic molecules ( statistical limit case) that the decay times and quantum yields can legitimately be handled by the Fermi golden rule ... [Pg.141]

If an analytical test results in a lower value x, < x0, then the customer may reject the product as to be defective. Due to the variation in the results of analyses and their evaluation by means of statistical tests, however, a product of good quality may be rejected or a defective product may be approved according to the facts shown in Table 4.2 (see Sect. 4.3.1). Therefore, manufacturer and customer have to agree upon statistical limits (critical values) which minimize false-negative decisions (errors of the first kind which characterize the manufacturer risk) and false-positive decisions (errors of the second kind which represent the customer risk) as well as test expenditure. In principle, analytical precision and statistical security can be increased almost to an unlimited extent but this would be reflected by high costs for both manufacturers and customers. [Pg.116]

In each case, the aim of quality control charts4 (QCC) is the representation of quality target values x0 (standard values) and their statistical limits. A control chart usually consists of five lines as shown in Fig. 4.14. [Pg.121]

To avoid misuse of a model for predicting (in this case) the intestinal absorption of compounds outside the model s present statistical limits, thus rendering the model (and/or statistical technique as well as the parameterization) a false bad reputation . [Pg.400]

Both Merritt and Hayes [639,640] and Merritt et al. [641] have investigated the statistical limits to attainable precision for GC-C-IRMS techniques. For carbon isotope ratio measurements with precision not limited by counting... [Pg.82]

The primary optimization target of CLs is the effectiveness factor of Pt utilization, Tcl- It includes a factor, that accounts for statistical limitations of catalyst utilization that arise on a hierarchy of scales, as specified in the following equafion. defermines the exchange current density ... [Pg.404]

The sensitivity of the Salmonella test may make it particularly useful for detecting chemicals that have weak carcinogenic activity and that would be difficult to identify in animal tests because of statistical limitations. [Pg.10]

Even with the Kelen Tudos refinement there are statistical limitations inherent in the linearization method. The independent variable in any form of the linear equation is not really independent, while the dependent variable does not have a constant variance [O Driscoll and Reilly, 1987]. The most statistically sound method of analyzing composition data is the nonlinear method, which involves plotting the instantaneous copolymer composition versus comonomer feed composition for various feeds and then determining which theoretical plot best fits the data by trial-and-error selection of r and values. The pros and cons of the two methods have been discussed in detail, along with approaches for the best choice of feed compositions to maximize the accuracy of the r and r% values [Bataille and Bourassa, 1989 Habibi et al., 2003 Hautus et al., 1984 Kelen and Tudos, 1990 Leicht and Fuhrmann, 1983 Monett et al., 2002 Tudos and Kelen, 1981]. [Pg.481]

The same statistical limits affect animal studies. To save money, researchers conducting animal experiments administer relatively high doses to a manageable number of subjects. Analysts then extrapolate from the results to infer effects at the low exposures that humans face. Animal studies are controversial because human and animal metabolisms differ. Even if the species did not differ, the problem of extrapolating from high-level to low-level exposure effects would remain. [Pg.67]

To discover smaller specific effects on the intramolecular dynamics after attachment of an Ar atom to the benzene molecule, we performed lifetime measurements of single rovibronic states in the 6q band of the benzene-Ar and the benzene-84 Kr complex. No dependence of the lifetime on the J K> quantum number within one vibronic band was found [38]. This is in line with the results in the bare molecule and points to a nonradiative process in the statistical limit produced by a coupling to a quasi-continuum, for example, the triplet manifold. [Pg.416]

The nature of the radiative decay in the resonance and in the statistical limits was considered by Berry and Jortner,7 who examined the interference effects in the radiative decay of coherently excited states. Quantum beat signals can be observed and used to analyze close-lying molecular... [Pg.183]

It should be pointed out that, as used here, the Green s function method implicitly assumes the existence of a continuum or quasicontinuum of states to be coupled with some discrete (or set of discrete) state(s). Thus, the generalized perturbation treatment is valid only in the statistical limit for the isolated molecule. [Pg.204]

There is no restriction on the magnitudes of f, and f , except that they must be infinitesimally small on the energy scale of interest. To insure compatibility of the treatment of Chock, Jortner, and Rice8 with the analysis of Bixon and Jortner in the statistical limit we must impose the condition... [Pg.209]

In the treatment of radiationless transitions presented above, we have mainly considered the case of a closed channel decaying into a single open channel, which latter consists of the dense vibronic manifold of some one electronic state (statistical limit). That description is obviously incomplete, since both radiative and nonradiative decay processes occur simultaneously. Clearly, a complete theoretical description of the radiationless transition... [Pg.231]

This equation can be considerably simplified in the following cases10 11 (a) In the statistical limit we are interested in the time scale t /e (see eq. (6-12)). Now, the integral (10-34) contains the function... [Pg.248]

Finally, in the statistical limit, the following simple relations are obtained10 ... [Pg.249]

Physical property Resonance limit Intermediate case Statistical limit... [Pg.251]

Now, in the statistical limit for which we can treat our final manifold of closely spaced twisted triplets as an effective continuum, the sum in eq. (12-24) can be replaced by a definite integral whose weight function is taken to be the density of vibronic states, p(E). Thus we write... [Pg.276]


See other pages where Statistical limit is mentioned: [Pg.781]    [Pg.789]    [Pg.27]    [Pg.41]    [Pg.441]    [Pg.39]    [Pg.174]    [Pg.349]    [Pg.4]    [Pg.7]    [Pg.14]    [Pg.74]    [Pg.106]    [Pg.518]    [Pg.411]    [Pg.412]    [Pg.413]    [Pg.421]    [Pg.442]    [Pg.786]    [Pg.786]    [Pg.183]    [Pg.183]    [Pg.184]    [Pg.225]    [Pg.226]    [Pg.232]    [Pg.249]    [Pg.250]    [Pg.280]   
See also in sourсe #XX -- [ Pg.42 ]

See also in sourсe #XX -- [ Pg.31 , Pg.32 , Pg.51 , Pg.52 , Pg.54 , Pg.134 , Pg.136 , Pg.137 , Pg.142 , Pg.144 , Pg.189 ]




SEARCH



Statistical limitations

© 2024 chempedia.info