Big Chemical Encyclopedia

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

Articles Figures Tables About

Stochastic modelling

Chapter 10 covers another important field with a great overlap with CA neural networks. Beginning with a short historical survey of what is really an independent field, chapter 10 discusses the Hopfield model, stochastic nets, Boltzman machines, and multi-layered perceptrons. [Pg.19]

One possibility for this was demonstrated in Chapter 3. If impact theory is still valid in a moderately dense fluid where non-model stochastic perturbation theory has been already found applicable, then evidently the continuation of the theory to liquid densities is justified. This simplest opportunity of unified description of nitrogen isotropic Q-branch from rarefied gas to liquid is validated due to the small enough frequency scale of rotation-vibration interaction. The frequency scales corresponding to IR and anisotropic Raman spectra are much larger. So the common applicability region for perturbation and impact theories hardly exists. The analysis of numerous experimental data proves that in simple (non-associated) systems there are three different scenarios of linear rotator spectral transformation. The IR spectrum in rarefied gas is a P-R doublet with either resolved or unresolved rotational structure. In the process of condensation the following may happen. [Pg.224]

The authors applied this model to the situation of dissolving and deposited interfaces, involving chemically interacting species, and included rate kinetics to model mass transfer as a result of chemical reactions [60]. The use of a stochastic weighting function, based on solutions of differential equations for particle motion, may be a useful method to model stochastic processes at solid-liquid interfaces, especially where chemical interactions between the surface and the liquid are involved. [Pg.80]

Inner slip, between the solid wall and an adsorbed film, will also influence the surface-liquid boundary conditions and have important effects on stress propagation from the liquid to the solid substrate. Linked to this concept, especially on a biomolecular level, is the concept of stochastic coupling. At the molecular level, small fluctuations about the ensemble average could affect the interfacial dynamics and lead to large shifts in the detectable boundary condition. One of our main interests in this area is to study the relaxation time of interfacial bonds using slip models. Stochastic boundary conditions could also prove to be all but necessary in modeling the behavior and interactions of biomolecules at surfaces, especially with the proliferation of microfluidic chemical devices and the importance of studying small scales. [Pg.82]

Exposure Uptake Biokinetic (IEUBK) model stochastic with probabilistic output sensitivity analysis lead exposure for children (6 months to 7 years old) across multiple pathways, routes, and environmental media, estimates blood lead concentrations (2005e)... [Pg.138]

Air Pollutants Exposure (APEX) model Stochastic time series simulation model producing probabilistic exposure distributions Used by USEPA to evaluate national ambient air quality standards (also part of Trim.Expo model) USEPA (2005b)... [Pg.139]

In the light of the previous discussion it is quite apparent that a detailed mathematical simulation of the combined chemical reaction and transport processes, which occur in microporous catalysts, would be highly desirable to support the exploration of the crucial parameters determining conversion and selectivity. Moreover, from the treatment of the basic types of catalyst selectivity in multiple reactions given in Section 6.2.6, it is clear that an analytical solution to this problem, if at all possible, will presumably not favor a convenient and efficient treatment of real world problems. This is because of the various assumptions and restrictions which usually have to be introduced in order to achive a complete or even an approximate solution. Hence, numerical methods are required. Concerning these, one basically has to distinguish between three fundamentally different types, namely molecular-dynamic models, stochastic models, and continuous models. [Pg.360]

Yoon, Smith, and Matsuda, on the other hand, compared two approaches, using a united-atom model and a fully atomistic model.Stochastic dynamics and MD simulations of w-tridecane (C13H28) were used to study polyethylene. Besides studying the bulk melt, the authors examined confined melts between solid surfaces. Chain conformations, chain packing orientational correlations, and self-diffusion were among the properties studied. In regard to chain confer-... [Pg.189]

Modelling Stochastic Fibrous Materials with Mathematical... [Pg.345]

Drug development could be improved by planning to develop and apply PM models along with novel pathways to approval, improved project management, and improved program development. Recent advances in computational speed, novel models, stochastic simulation methods, real-time data collection, and novel biomarkers all portend improvements in drug development. [Pg.2]

Deterministic models, simple error models, stochastic systems... [Pg.27]

Data analysis method Stating the software, model building procedures, model diagnostics, structural model, covariate model, stochastic model, and sensitivity analysis to be used and how the evaluation of the model is to be conducted... [Pg.292]

Fig. 13 The pressure dependence of the average number of branches obtained from the model stochastic simulations with different primary and secondary insertion barriers, AE1,AE2 (left) and examples of polymer topologies (right). Different atom shadings are used to mark different types of branches (primary, secondary, etc.)... Fig. 13 The pressure dependence of the average number of branches obtained from the model stochastic simulations with different primary and secondary insertion barriers, AE1,AE2 (left) and examples of polymer topologies (right). Different atom shadings are used to mark different types of branches (primary, secondary, etc.)...
DES can be used for deterministic as well as stochastic modeling. For modeling stochastic systems, the probability distribution of the... [Pg.1121]

In the area of isotactic polypropylene, there have been several publications (4 6) where the two-site model stochastic parameters are successfully utilized to explain the effect of external donors that are used in combination with solid catalyst con onent. However, few studies employing the two-site model have been made of the effect of internal donor on catalyst components. [Pg.209]

As mentioned, the uncertainty in Wf ) could come from stochastic uncertainty, model uncertainty or data and parameter uncertainty. In our model, stochastic uncertainly is related to the random behavior of z(t). Model uncertainty will more or less always be present, as g() only is a simplification of the leaUly. Data and parameter uncertainty is in this context related to both the parameters in g() as well as the parameters in the probability distribution of z(t). [Pg.641]

Beamon [51] reviewed the relevant research on supply chain design and analysis, and proposed some future research directions. Supply chain model is divided into deterministic models, stochastic analytical models, economic models, and simulation models. The future directions of the research include supply chain performance measurement methods, the establishment of the decision-making model and developing standards and technology of supply chain design and analysis. [Pg.21]

Square-root-sum-of-squares (SRSS) and arithmetic are common techniques for combining uncertainties. Other more complex techniques, including probabilistic modeling, stochastic modeling, or a combination of these techniques may also be used. [Pg.237]

Madadi et al. (2014) D S, T C RE SP PHM QN, EX Two stage model, stochastic factors after facilities are fixed, unreliable supply... [Pg.49]


See other pages where Stochastic modelling is mentioned: [Pg.72]    [Pg.532]    [Pg.135]    [Pg.24]    [Pg.186]    [Pg.286]    [Pg.345]    [Pg.126]    [Pg.126]    [Pg.127]    [Pg.133]    [Pg.532]    [Pg.2089]    [Pg.478]    [Pg.853]    [Pg.126]    [Pg.126]    [Pg.127]    [Pg.133]    [Pg.267]    [Pg.97]    [Pg.74]    [Pg.532]    [Pg.978]    [Pg.487]    [Pg.59]    [Pg.177]    [Pg.66]    [Pg.99]   
See also in sourсe #XX -- [ Pg.191 , Pg.234 , Pg.242 ]




SEARCH



Stochastic modeling

© 2024 chempedia.info