Big Chemical Encyclopedia

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

Articles Figures Tables About

Rule-based method

The essence of the configurational bias Monte Cculo method is that a growing molecuh preferentially directed (i.e. biased) towards acceptable structures. The effects of th biases can then be removed by modifying the acceptance rules. The configuratio bias methods are based upon work published in 1955 by Rosenbluth and Rosenbli... [Pg.459]

Ihe rule-based approach to protein structure prediction is obviously very reliant on th quality of the initial secondary structure prediction, which may not be particularly accurate The method tends to work best if it is known to which structural class the protein belongs this can sometimes be deduced from experimental techniques such as circular dichroism... [Pg.537]

The multienergy method is based on the concept that, if detonation of unconflned parts of a vapor cloud can be ruled out, strong blast is generated only by those cloud portions which bum under intensely turbulent conditions. Such cloud portions include, for instance, intensely turbulent fuel-air jets resulting from a high-pressure... [Pg.250]

To date, many of the reported ADME/Tox models have been rule based. For example, some research groups have used relatively simple filters like the rule of 5 [93] and others [94] to limit the types of molecules evaluated with in silico methods and to focus libraries for HTS. However, being designed as rapid computational alert tools aimed at a single property of interest, they cannot offer a comprehensive picture when it comes to understanding ADME properties. [Pg.366]

QSAR modeling. Therefore considerably larger and more consistent data sets for each enzyme will be required in future to increase the predictive scope of such models. The evaluation of any rule-based metabolite software with a diverse array of molecules will indicate that it is possible to generate many more metabolites than have been identified in the literature for the respective molecules to date, which could also reflect the sensitivity of analytical methods at the time of publishing the data. In such cases, efficient machine learning algorithms will be necessary to indicate which of the metabolites are relevant and will be likely to be observed under the given experimental conditions. [Pg.458]

The common method of treating rod-pumped wells is to periodically batch inhibitor into them. The treatment period for a given well is selected using empirical rules based on well production volumes. A successful and economic corrosion inhibition program must carefully control the inhibitor concentration in the well fluids. Environmental aspects and efficacious inhibitor usage necessitate the measurement of very low corrosion inhibitor concentrations. Inhibitor concentrations as low as one part per million are significant, thus... [Pg.85]

Direct search methods use only function evaluations. They search for the minimum of an objective function without calculating derivatives analytically or numerically. Direct methods are based upon heuristic rules which make no a priori assumptions about the objective function. They tend to have much poorer convergence rates than gradient methods when applied to smooth functions. Several authors claim that direct search methods are not as efficient and robust as the indirect or gradient search methods (Bard, 1974 Edgar and Himmelblau, 1988 Scales, 1986). However, in many instances direct search methods have proved to be robust and reliable particularly for systems that exhibit local minima or have complex nonlinear constraints (Wang and Luus, 1978). [Pg.78]

Application of ultra-high-throughput in silico estimation of biopharmaceutical properties to the generation of rule-based computational alerts has the potential to improve compound selection to those drug candidates that are likely to prove less troublesome in their development. The extension of purely in silico methods to the realm of mechanistic simulation further enhances our ability to predict the impact of physiological and biochemical process on drug absorption and bioavailability. [Pg.439]

The Le Bas method is based on a summation of atomic volumes with adjustment for the volume decrease arising from ring formation. The full method is described by Reid et al. (1987), but for the purposes of this compilation, the volumes and rules as listed in Table 1.3.1 are used. [Pg.14]

From the different planning methods available within SNP, SNP optimization is selected because it offers the best fit to the customer requirements outlined above. The main reasons for this decision are the multisourcing characteristics of the supply network as well as the fact that the objective functions used by the SNP optimizer, profit maximization or cost minimization, correspond to the planning philosophy favored by the customer. In addition to SNP optimization with its cost-based approach, SNP offers several heuristic-based planning methods which follow a rule-based logic. [Pg.248]

To verify that there was no obvious redundancy in the assay data, a subset of 80 assays and 1600 compounds was analyzed using the KEM approach [19-21] developed by Ariana [22], a systematic rule-based method that identifies all relations of the type A —> B, A and B —> C and not D. No such noncontradicted relations were found, even using very large activity bins, showing that there is signal in all the assay data, including those from related assays. [Pg.30]

In this case, systematic methods for generation of feasible molecular and mixture candidates have been reported for the design of functional chemical products [see Achenie et al (2003)]. Methods based on database search, total enumeration of feasible candidates (rule-based techniques that avoid a combinatorial explosion), mathematical programming, genetic algorithm, and,... [Pg.12]

For a review of the application of the Darken and Gurry method to predict solid solubility see Gschneidner Jr. (1980). An improvement of the method by means of simultaneous use of rules based on the electronic and crystal structures of the metals involved is also presented. Notice that, in a way, the Darken and Gurry diagram corresponds to a row, or to a column, of the map reported in Fig. 2.8. [Pg.28]

A potentially much more adaptable technique is force-field vibrational modeling. In this method, the effective force constants related to distortions of a molecule (such as bond stretching) are used to estimate unknown vibrahonal frequencies. The great advantage of this approach is that it can be applied to any material, provided a suitable set of force constants is known. For small molecules and complexes, approximate force constants can often be determined using known (if incomplete) vibrational specha. These empirical force-field models, in effect, represent a more sophisticated way of exhapolating known frequencies than the rule-based method. A simple type of empirical molecular force field, the modified Urey-Bradley force field (MUBFF), is introduced below. [Pg.79]

An example of the cure cycle optimization is the work of Thomas et al. who used a very sophisticated model, together with a rule-based optimization routine, to pick the shortest cure cycle that met a set of performance criteria [15]. Reductions in cure time using this method ranged up to 36 percent for a single complex part and from 8 percent up to 43 percent for batches of mixed parts. Rejection rates were not increased in any case, and they were actually reduced significantly for one part. This model, although transferred to a number of companies, unfortunately has had limited use because of the lack of support for the code and the cost of qualifying it on new materials. [Pg.455]

We follow a rule-based method when we analyze risk objects and components and their attributes.These plug-and-play rules can be different for different subjects, research areas, and industries. They can be designed and standardized for different industry sectors, enabling an analytical approach, systematic standardization, and accurate and predictable results. [Pg.183]


See other pages where Rule-based method is mentioned: [Pg.351]    [Pg.351]    [Pg.109]    [Pg.535]    [Pg.167]    [Pg.167]    [Pg.532]    [Pg.276]    [Pg.142]    [Pg.290]    [Pg.455]    [Pg.484]    [Pg.197]    [Pg.503]    [Pg.4]    [Pg.83]    [Pg.74]    [Pg.374]    [Pg.344]    [Pg.343]    [Pg.424]    [Pg.84]    [Pg.180]    [Pg.129]    [Pg.224]    [Pg.148]    [Pg.157]    [Pg.280]    [Pg.351]    [Pg.92]    [Pg.160]    [Pg.91]    [Pg.356]    [Pg.513]    [Pg.318]   
See also in sourсe #XX -- [ Pg.97 ]




SEARCH



Fuzzy Rule Based Method

Rule-based methods, spectrum prediction

Structure generation rule-based methods

© 2024 chempedia.info