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Requirement for the Model

As a starting point, it was made clear that the requirement for the model. The following questions are answered that were stated in section 1.4. [Pg.206]

Is model necessary for control How about dynamics based control  [Pg.206]

The first question was the necessary accuracy and precision of the model. This determines the possible level of approximation. We proposed overall modelhng framework for dealing with electrochemical process and mechanical process in parallel, and interface them afterward. With this framework, it was made clear that the required resolution for these processes. The resolution was examined by comparing simulation and experimental results. The simulation results well confirmed the experimental results throughout chapter 3 to chapter 8. [Pg.206]


A complex reaction system cannot be considered completely in most cases. The number of simplifications required for the model increases with the growing complexity of the system. [Pg.178]

The second criterion is quite interesting. It requires demonstrating if the model, which fulfills the requirements for the model, is appropriate for the chemical it has been applied to. Thus, it is not enough to demonstrate that the model works. It is assumed that it does not work in all cases. Thus, a specific evaluation has to be done. [Pg.85]

Whatever the aim of a particular titration, the computation of the position of a chemical equilibrium for a set of initial conditions (e.g. total concentrations) and equilibrium constants, is the crucial part. The complexity ranges from simple 1 1 interactions to the analysis of solution equilibria between several components (usually Lewis acids and bases) to form any number of species (complexes). A titration is nothing but a preparation of a series of solutions with different total concentrations. This chapter covers all the requirements for the modelling of titrations of any complexity. Model-based analysis of titration curves is discussed in the next chapter. The equilibrium computations introduced here are the innermost functions required by the fitting algorithms. [Pg.40]

In Chapter 3, we supply the theory required for the modelling of chemical processes. Many of the example data sets used for both kinds of analyses are taken from kinetics and equilibrium processes. This reflects the background of both authors. In fact, this part of the book serves as a solid introduction to the simulation of equilibrium processes such as titrations and the simulation of complex kinetic processes. The example routines are easily adapted to the processes investigated by the reader. They are very general and there is essentially no limit to the complexity of the processes that can be simulated. [Pg.336]

Gross (1983) expanded the mathematical treatment to the general problem required for the model and incorporated the CO conversion into the model. The treatment by Gross will be utilized because it is more general than the Weisz treatment. [Pg.46]

The equations (20) to (30) provide the basis for predicting the adsorption rate profiles for the binary system. The input parameters required for the model are the single-solute film transfer and surface diffusion coefficients, the single-solute isotherm constants and the mixture equilibria coefficients. The rate parameters were obtained from single solute rate data (20), and the equilibrium parameters were obtained from single and multi-solute equilibrium data. [Pg.40]

As implied by the vertices and closed circles in Figure 11, a minimum of seven experiments were required for the modeling and optimization process. The resolution between all pairs of peaks was measured and then modeled using equations of the form... [Pg.335]

Determined the fluid physical properties required for the model fluid to achieve dynamic similarity between prototype and model. [Pg.186]

Admittedly, in the strictly theoretical sense, such a verification is a necessary but not sufficient requirement for the model to be the true model. It should be obvious to readers familiar with current research work on the nitration of aromatic compounds that the assumptions and mechanisms on which this model is based are under debate, albeit generally accepted. Exhaustive testing and verification of a model is usually not justifiable in a business... [Pg.412]

In this chapter, we describe the methods required for the model-based analysis of multivariate measurements of chemical reactions. This comprises reactions of essentially any complexity in solution, but it does not include the investigation of gas-phase reactions, for example in flames or in the atmosphere, which involve hundreds or even thousands of steps [7-12],... [Pg.219]

How many degrees-of-freedom are required for the model How many are available for replication and so how many left to determine the significance of the lack-of-fit ... [Pg.107]

The average dimensions, or other statistical properties of the polymeric chains, are then calculated, allowing for the relative probabilities of the rotational states and making full allowance for the mutual interdependence of adjacent pairs of bond rotational states. Parameters required for the models are normally obtained from molecular structure data and from experimental information relating to the statistical conformations of the polymeric chains. Further references to rotational isomeric state models will be made later. [Pg.45]

For the case of hard spheres Eq. (6.3) collapses to the result of Eq. (6.2). The only information required for the model is an estimate of the form of the atom-molecule potential F(l ) within several kT of the binding energy of the pair. The collision integral is... [Pg.434]

These conditions lead us to the following requirements for the modeling, respectively. [Pg.159]

Computational modeling is a powerful tool to predict toxicity of drugs and environmental toxins. However, all the in silico models, from the chemical structure-related QSAR method to the systemic PBPK models, would beneht from a second system to improve and validate their predictions. The accuracy of PBPK modeling, for example, depends on precise description of physiological mechanisms and kinetic parameters applied to the model. The PBPK method has primary limitations that it can only predict responses based on assumed mechanisms, without considerations on secondary and unexpected effects. Incomplete understanding of the biological mechanism and inappropriate simplification of the model can easily introduce errors into the PBPK predictions. In addition values of parameters required for the model are often unavailable, especially those for new drugs and environmental toxins. Thus a second validation system is critical to complement computational simulations and to provide a rational basis to improve mathematical models. [Pg.717]

Because the j values are equally spaced, AX. = j - j-i is constant and only relative X values are required for the model. [Pg.39]

The model of Lapidus and Amundson [5] is the focal point of study of linear and nonlinear chromatography. Since in chromatography we have two independent variables, z and t, and two dependent variables, the concentrations of the solute in the mobile and the stationary phases, C and Cg, respectively, two equations are required for the model to permit the calculation of C(x, t) and Cs x, t). The model of Lapidus and Amundson considers a set of two partial differential equations for a single component. The first equation is the mass balance equation (Eq. 2.2)... [Pg.473]

CHEOPS obtains this setup file in XML format from ModKit-l-. Tool wrappers are started according to this XML file. The input files required for the modeling tools Aspen Plus and gPROMS are obtained from the model repository ROME. CHEOPS applies a sequential-modular simulation strategy implemented as a solver component because all tool wrappers are able to provide closed-form model representations. The iterative solution process invokes the model evaluation functionality of each model representation, which refers to the underljdng tool wrapper to invoke the native computation in the modeling tool the model originated from. Finally, the results of all stream variables are written to a Microsoft Excel table when the simulation has terminated. [Pg.491]

The method to estimate corrosion costs was patterned after Battelle-NBS lO method. Data gathered and information required for the model s adjustments came from three sources (i) data compiled from a survey specifically designed for industries in Kuwait (ii) judgment of experts in corrosion in Kuwait (iii) experience of other countries and previous studies. [Pg.114]

This system being distributed in a space with three dimensions, three levels of spatial reduction are required for the model. Among the six reduced variables, two are therefore essential for being... [Pg.109]

Modeling in LFT form requires for the model to be proper and observable [13]. The bond graph methodology allows by causal manipulations, the verification of these properties directly on the bond graph model. [Pg.111]

On the first sight it does not seem to be reasonable to consider general model checkers as relevant independent tools for formal verification of an existing OS. While many different tools use model checkers as their backends, verifying a complete model of the entire system created by hand seems to be infeasible both in the sense of time required for the model creation and resources required by the checker to finish the exhaustive traversal of the model s state space. [Pg.81]


See other pages where Requirement for the Model is mentioned: [Pg.599]    [Pg.129]    [Pg.98]    [Pg.387]    [Pg.122]    [Pg.12]    [Pg.11]    [Pg.297]    [Pg.89]    [Pg.2178]    [Pg.89]    [Pg.416]    [Pg.148]    [Pg.424]    [Pg.178]    [Pg.438]    [Pg.442]    [Pg.2177]    [Pg.1250]    [Pg.565]    [Pg.838]    [Pg.2629]    [Pg.311]    [Pg.433]    [Pg.206]   


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