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The analysis of a risk—that is, its estimation—leads to the assessment of that risk and the decision-making processes of selecting the appropriate level of risk reduction. In most studies this is an iterative process of risk analysis and risk assessment until the risk is reduced to some specified level. The subjec t of acceptable or tolerable levels of risk that coiild be applied to decision making on risks is a complex subject which will not oe addressed in this section. [Pg.2276]

The solution of these equations requires a root-finding algorithm which iterates on assumed values of T i. At each value of T i, solve Eq. (26-95) (with T]i replacing Ra) foi Find R2 ffom Eq. (26-101), subject also to ... [Pg.2351]

A three-dimensional analog of a Conway object is then defined to be an expansion sucli that, when subjected to the appropriate three-dimensional Life-rule, yields after each and every generation a projection that is identical to the original Conway object for the same iteration step under Conway s original two-dimensional... [Pg.154]

Remark Condition (11) for fixed B may be viewed as a selection rule for those values of r for which the iterations converge. For example, for the explicit scheme with the identity operator B = E condition (IT) is ensured if all the eigenvalues are subject to the relation... [Pg.659]

Implicit iteration schemes. Convergence of implicit iteration schemes was the subject of investigation in Section 2 for the special case... [Pg.679]

Linear models with respect to the parameters represent the simplest case of parameter estimation from a computational point of view because there is no need for iterative computations. Unfortunately, the majority of process models encountered in chemical engineering practice are nonlinear. Linear regression has received considerable attention due to its significance as a tool in a variety of disciplines. Hence, there is a plethora of books on the subject (e.g., Draper and Smith, 1998 Freund and Minton, 1979 Hocking, 1996 Montgomery and Peck, 1992 Seber, 1977). The majority of these books has been written by statisticians. [Pg.23]

Based on the above, we can develop an "adaptive" Gauss-Newton method for parameter estimation with equality constraints whereby the set of active constraints (which are all equalities) is updated at each iteration. An example is provided in Chapter 14 where we examine the estimation of binary interactions parameters in cubic equations of state subject to predicting the correct phase behavior (i.e., avoiding erroneous two-phase split predictions under certain conditions). [Pg.166]

On the subject of comparing iterative methods a word of caution is in order. Clearly in any quantitative comparison, the termination criteria should be comparable and the benchmark problems should be run on the same computer. Yet even for simple problems and methods, these two requirements prove to be difficult to enforce and insufficient to ensure meaningful comparisons. To allow for the fact that different methods do not terminate at exactly the same point even when the same termination criterion is used, Broyden (B13) introduced a mean convergence rate, R, which is... [Pg.157]

A more subjective approach to the multiresponse optimization of conventional experimental designs was outlined by Derringer and Suich (22). This sequential generation technique weights the responses by means of desirability factors to reduce the multivariate problem to a univariate one which could then be solved by iterative optimization techniques. The use of desirability factors permits the formulator to input the range of property values considered acceptable for each response. The optimization procedure then attempts to determine an optimal point within the acceptable limits of all responses. [Pg.68]

A more precise question (Bethke, 1992) is the subject of this chapter in geochemical modeling is there but a single root to the set of governing equations that honors a given set of input constraints We might call such a property mathematical uniqueness, to differentiate it from the broader aspects of uniqueness. The property of mathematical uniqueness is important because once the software has discovered a root to a problem, the modeler may abandon any search for further solutions. There is no concern that the choice of a starting point for iteration has affected the answer. In the absence of a demonstration of uniqueness, on the other hand, the modeler cannot be completely certain that another solution, perhaps a more realistic or useful one, remains undiscovered. [Pg.181]

For reasons discussed above, we needed a complementary, ancillary tool for comparison of the mass spectra of components from multiple urine samples. We desired that the procedure have several characteristics (1) requires little if any manual data entry by the operator (2) utilizes data automatically generated by ChemStation and organized into Microsoft Excel spreadsheets (3) displays both retention times and mass spectral data in the same window (4) minimizes subjective operator judgments and (5) is simple and rapid to use. What emerged after several iterative improvements are the FindPeak macros discussed below. These are largely due to the expertise of Y. Aubut, with valuable input from J. Eggert. [Pg.30]

This chapter discusses various analysis methods for determining the dynamic response of structural members subjected to blast loading. In order to perform the dynamic analyses, it is necessary to have previously defined the loading as well as member properties such as stiffness and mass. The design of new structures sometimes involves several iterations of the analysis, where trial member sizes are used and the resulting response quantities are compared against the acceptance criteria defined in Chapter 5. [Pg.37]

The commercially available software (Maximum Entropy Data Consultant Ltd, Cambridge, UK) allows reconstruction of the distribution a.(z) (or f(z)) which has the maximal entropy S subject to the constraint of the chi-squared value. The quantified version of this software has a full Bayesian approach and includes a precise statement of the accuracy of quantities of interest, i.e. position, surface and broadness of peaks in the distribution. The distributions are recovered by using an automatic stopping criterion for successive iterates, which is based on a Gaussian approximation of the likelihood. [Pg.189]

The working hypotheses and the model were consulted in a multi-stage iterative working process, for the one part, for interpretation of the 13 case studies and, for the other part, were further developed on the basis of findings from the case studies. In addition, the contributions from the events relating to certain sectional subjects were integrated. [Pg.61]

Pre-equihbrated protocols can enable constituent amplification when run iteratively. This is referred to as the iterative approach. The DCL is generated under dynamic conditions, and then subjected to static selection. After static selection, however, the selected components must be removed, for example, by using immobihzed targets. The unbound species are then... [Pg.170]

The IR methods have progressed from hand-drawn baselines and peak height or area for quantitation, to spectral subtraction, to leastsquares methods. Least-squares analysis eliminates the reliance on single peaks for quantitation and the subjectivity of spectral subtraction. However, negative concentration coefficients are a problem with least-squares analysis, since they have no physical meaning. Negative components can be omitted according to some criterion and the least-squares process iterated until only... [Pg.49]

One of the important advantages of the intramolecular alkene silylformylation reaction as an aldol equivalent is that the products are masked 3,5-dihydroxyalkanals, and therefore that no manipulations are required prior to iteration of the process by aldehyde al-lylation to set up the next intramolecular silylformylation. Given that allylsilanes are well-known aldehyde allylation reagents, intramolecular silylformylation employing a diallylhydrosilane would, in principle, allow for the possibility of a tandem silylformyla-tion/allylsilylation reaction. This has been reduced to practice the diaUylsilyl ethers 60 were subjected to the previously developed silylformylation conditions and the unpuri-fied reaction mixtures were subjected to the Tamao oxidation ]36] to provide triols 61... [Pg.104]


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See also in sourсe #XX -- [ Pg.491 ]




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