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Stochastic branching process

The probability measure on the set of such configurations can be constructed for some classes of statistically branched polymers whose [Pg.173]

A simple algorithm (Kuchanov et al., 1988) enables one to determine the probability of any fragments of macromolecules of the Gordonian polymers. Their comparison with the NMR spectroscopy data permits estimating the adequacy of the chosen kinetic model of the process of synthesis of a particular polymer specimen. These probabilities also enter in the expressions for the glass transition temperature and some structure-additive properties of randomly branched polymers (Chompff, 1971). [Pg.174]


The basis of model calculations for copolymerization, branching and cross-linking processes is the stochastic theory of Flory and Stockmayer (1-3). This classical method was generalized by Gordon and coworkers with the more powerful method of probability generating functions with cascade substitution for describing branching processes (4-6). With this method it is possible to treat much more complicated reactions and systems (7-9). [Pg.213]

In this study computational results are presented for a six-component, three-stage process of copolymerization and network formation, based on the stochastic theory of branching processes using probability generating functions and cascade substitutions (11,12). [Pg.214]

In the stochastic theory of branching processes the reactivity of the functional groups is assumed to be independent of the size of the copolymer. In addition, cyclization is postulated not to occur in the sol fraction, so that all reactions in the sol fraction are intermolecular. Bonds once formed are assumed to remain stable, so that no randomization reactions such as trans-esterification are incorporated. In our opinion this model is only approximate because of the necessary simplifying assumptions. The numbers obtained will be of limited value in an absolute sense, but very useful to show patterns, sensitivities and trends. [Pg.214]

POLYMQ is similar to POLYM, but with the additional tetrafunc-tional 0 monomers in stage 1. These two programs contain the formulae derived with the stochastic theory of branching processes which are also specified elsewhere (12). [Pg.215]

A general theory of the equilibrium polycondensation of an arbitrary mixture of monomers, described by the FSSE model, has been developed [75]. Proceeding from rigorous thermodynamic considerations a branching process has been indicated which describes the chemical structure of condensation polymers and expressions have been derived which relate the probability parameters of this stochastic process to the thermodynamic parameters of the FSSE model. [Pg.198]

Note that the stochastic branching annotations and reward structures presented here are simple additions to the BPMN language, or other graph based process languages, and do not alter the implied semantics of the language. [Pg.2408]

SBOAT is a Stochastic BPMN Optimisation and Analysis Tool, which allows a user to model, and annotate with rewards and stochastic branching, a business processes as a BPMN BPD. Analysis is specified using a PRISM style PCTL query and depending on the nature of the query one or number of results are calculated. At the core of SBOAT is the PRISM model checker (Kwiatkowska, Norman, Parker 2011) which performs analysis of individual models generated by the SBOAT. An overview of the design of SBOAT is shown in Figure 5. [Pg.2411]

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 advantage of the kinetic theory over the statistical branching theory rests in its adherence to the kinetically controlled chemical process while the statistical theory working with units does not take into consideration the coimections between units developed in time (stochastic correlations). The greater mathematical complexity and impossibility to get information on the internal structure of the molecules and gel are the disadvantages of the kinetic theory. [Pg.21]

A hundred years after Einstein s seminal work [4], the theory of stochastic processes has been put on solid physical and mathematical foundations, at the same time playing a prominent role in many branches of science [36,107-109]. [Pg.488]

Harwood and Payne (210) have demonstrated a simple, general relationship between the work input at break, Ub, and the hysteresis at break, Hb. The latter is defined as the area of the hysteresis loop formed between the extension and retraction branches of the strain curve, obtained in uniaxial tension at constant strain rate. Hb may be obtained by measuring hysteresis loops for various strain ranges (0 to e) and extrapolating the area of the loop to the breaking strain, eb. In a single experiment, the cross-head travel must be reversed just short of eb, which is not easily done in view of the stochastic nature of the failure process. The empirical relationship between Ub and Hb is... [Pg.218]


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