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Formulation of the Models

A thin isotropic homogeneous plate is assumed to occupy a bounded domain C with the smooth boundary T. The crack Tc inside 0 is described by a sufficiently smooth function. The chosen direction of the normal n = to Tc defines positive T+ and negative T crack faces. [Pg.159]

There exists a unique solution IK G if of the variational inequality (2.265). [Pg.160]

Assume that the solution W of (2.265) is sufficiently smooth. We use Green s formula [Pg.160]


The final step in the formulation of the model [4-6] is to recognize that the second-order term, say, must be a quadratic function of the angular... [Pg.72]

As will be seen later, these techniques will prove to be useful when solving design problems in general-purpose software, such as spreadsheets. Many of the numerical problems associated with optimization can be avoided by appropriate formulation of the model. Further details of model building can be found elsewhere12. [Pg.53]

The physical significance of the parameters (or K ) and K is obviously of considerable interest. In the formulation of the model, these are simply arbitrary parameters which define, respectively, the extent of primary and multiple adsorption. For the particular case evaluated above (x=0.5 and xs=l 0) K is approximately constant while appears to decrease exponentially with chain length n. It is expected that, for a given chain length, the parameters and K will both depend on x and X Further comparisons, similar to that given here, will be required to establish the precise correspondence of the parameters used in the two approaches. [Pg.31]

The mathematical formulation of the model and the definition of the variables and parameters are given in Box 23.1. Note that the model is based on the following simplifying assumptions ... [Pg.1054]

The assumptions of the special model of a nonuniform surface were formulated above in terms of changes of the standard Gibbs energy, AG°, and the Gibbs activation energy, AG. It can be assumed that standard entropy, S°, of each kind of adsorbed particles and activated complexes on different sites of a nonuniform surface does not differ substantially in this case there can be given practically equivalent formulation of the model... [Pg.210]

The boundary and initial conditions are always defined by the assumptions that have been made in the formulation of the model. These, in turn, depend... [Pg.34]

This method, which was designed for use with spectroscopic data, derives its name from the formulation of the model, which is a direct, classical expression of Beer s Law for a system with multiple analytes ... [Pg.257]

The dynamic formulation of the model equations requires a careful analysis of the whole system in order to prevent high-index problems during the numerical solution (144). As a consequence, a consistent set of initial conditions for the dynamic simulations and suitable descriptions of the hydrodynamics have to be introduced. For instance, pressure drop and liquid holdup must be correlated with the gas and liquid flows. [Pg.348]

The mathematical formulation of the model complicates somewhat (4), and it is not reported here for the sake of simplicity. [Pg.341]

To complete the formulation of the model, we have to include the interaction of the system with electronic reservoirs in order to describe charge transport along the same lines as before. We assume, as usual, a tunnel-type Hamiltonian with the form ... [Pg.315]

Abstract An alternative formulation of the model for chemical osmosis in clay membranes... [Pg.275]

The first quantitative atomic model appeared early in the previous century, based on the pioneering work of Lord Rutherford and the Danish physicist Niels Bohr. It was devised in simple analogy with Kepler s model of the solar system and, despite a number of known fatal defects, it has such intuitive appeal that, even today, scientists and non-scientists alike accept it as the most reasonable working model for understanding the distribution of electrons in atoms. Formulation of the model was guided by three important experimental observations which had no obvious explanation in terms of 19th century physics. [Pg.22]

Nonlinear mixed-effects modeling methods as applied to pharmacokinetic-dynamic data are operational tools able to perform population analyses [461]. In the basic formulation of the model, it is recognized that the overall variability in the measured response in a sample of individuals, which cannot be explained by the pharmacokinetic-dynamic model, reflects both interindividual dispersion in kinetics and residual variation, the latter including intraindividual variability and measurement error. The observed response of an individual within the framework of a population nonlinear mixed-effects regression model can be described as... [Pg.311]

The formulation of the model is based on the stoichiometrical equation (4.44) to relate pollutant and coagulant reagent, where coefficient n has to be determined experimentally... [Pg.120]

The formulation of the model as above has the advantage that mathematically it picturizes the bed as an initial value problem in contrast to the more complicated boundary value representation of the Fryer-Potter model. The implications of this reduced complexity become more evident (and considerably more important) when the reactions involved are nonlinear. [Pg.27]

Formulation of the model is completed by the specification of initial and boundary conditions. The initial condition/ the state of the system just before exposing the interface to drug (the beginning of the intraperi-toneal infusion in our example)/ is that the tissue concentration is everywhere zero, that iS/ C(X/0) = 0. At all times at the fluid-tissue interface/ the extracellular concentration equals the infusate concentration that iS/... [Pg.109]

Roberts, M.S. Rowland, M. A dispersion model of hepatic ehmination 1. formulation of the model and bolus considerations. J. Pharmacokinet. Biopharm. 1986, 14, 227-260. [Pg.589]

This work presents the on-line level control of a batch reactor. The on-line strategy is required to accommodate the reaction rate disturbances which arise due to catalyst dosing uncertainties (catalyst mass and feeding time). It is concluded that the implemented shrinking horizon on-line optimization strategy is able to calculate the optimal temperature profile without causing swelling or sub-optimal operation. Additionally, it is concluded that, for this process, a closed-loop formulation of the model predictive controller is needed where an output feedback controller ensures the level is controlled within the discretization intervals. [Pg.530]


See other pages where Formulation of the Models is mentioned: [Pg.328]    [Pg.159]    [Pg.515]    [Pg.191]    [Pg.132]    [Pg.176]    [Pg.176]    [Pg.353]    [Pg.299]    [Pg.2]    [Pg.106]    [Pg.136]    [Pg.136]    [Pg.17]    [Pg.236]    [Pg.17]    [Pg.939]    [Pg.103]    [Pg.178]    [Pg.118]    [Pg.57]    [Pg.542]    [Pg.404]    [Pg.112]    [Pg.100]    [Pg.30]    [Pg.184]    [Pg.117]    [Pg.132]    [Pg.16]    [Pg.262]    [Pg.393]   


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Model formulation

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