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Model defined

The inverse of the Cauchy-Green tensor, Cf, is called the Finger strain tensor. Physically the single-integral constitutive models define the viscoelastic extra stress Tv for a fluid particle as a time integral of the defonnation history, i.e. [Pg.87]

The usual alignment algorithm fixes 0 and A as 0o and Aq, so that the prior is 1 when 0 = 00 and A = Aq and is 0 otherwise. Clearly, if experience justifies this choice or some other nonuniform choice, we can choose an informative prior that biases the calculation to certain values for the parameters or limits them to some likely range. The likelihood is well defined by the alignment model defined by using a similarity matrix and affine gap penalties, so that... [Pg.335]

Once the indicator is defined, a model can be developed that predicts the indicator value as a function of an emission. Such models are normally simple linear models defined by characterization factors. If an emission is niuitiplied by a characterization factor, an indicator value is obtained. [Pg.1363]

The Isodensity PCM (IPCM) model defines the cavity as an isodensity surface of the molecule. This isodensity is determined by an iterative process in which an SCF cycle is performed and converged using the current isodensity cavity. The resultant wavefunction is then used to compute an updated isodensity surface, and the cycle is repeated until the cavity shape no longer changes upon completion of the SCF. [Pg.238]

Models which include exact exchange are often called hybrid methods, the names Adiabatic Connection Model (ACM) and Becke 3 parameter functional (B3) are examples of such hybrid models defined by eq. (6.35). The <, d and parameters are determined by fitting to experimental data and depend on the form chosen for typical values are a 0.2, d 0.7 and c 0.8. Owing to the substantially better performance of such parameterized functionals the Half-and-Half model is rarely used anymore. The B3 procedure has been generalized to include more filling parameters, however, the improvement is rather small. [Pg.188]

This method can also be employed with the operational model. Specifically, the operational model defines receptor response as... [Pg.92]

Hunter and Reimer (1965) proposed the simple Divergence criterion that can readily be extended to multi-response situations. In general, if we have performed N experiments the experimental conditions xN+] for the next one are obtained by maximizing the weighted Divergence between the rival models, defined as... [Pg.192]

Deposition of inhaled gases and vapors is modeled as a partitioning process that depends on the physiological parameters noted above as well as the solubility and reactivity of a compound in the respiratory tract (see Figure 3-3). The ICRP (1994b) model defines three categories of solubility and reactivity SR-0, SR-1, and SR-2 ... [Pg.78]

In PLS analysis a distance to the overall model (distance-to-model), defined as the variance in the descriptors remaining after the analysis (residual standard deviation RSD), is given for each predicted compound. This is a very important piece of information that is presented to the researcher (see Section 16.5.4). [Pg.399]

The different behaviour of contact resistance in the two cases can be examined through the two models the just described acoustic mismatch model and the diffuse mismatch model which suppose that all the phonons are scattered at the interface. Hence these two models define two limits in the behaviour of phonons at a discontinuity. [Pg.111]

The first and most critical step in developing a geochemical model is conceptualizing the system or process of interest in a useful manner. By system, we simply mean the portion of the universe that we decide is relevant. The composition of a closed system is fixed, but mass can enter and leave an open system. A system has an extent, which the modeler defines when he sets the amounts of fluid and mineral considered in the calculation. A system s extent might be a droplet of rainfall, the groundwater and sediments contained in a unit volume of an aquifer, or the world s oceans. [Pg.7]

There is no restriction against applying polythermal models in open systems. In this case, the modeler defines mass transfer as well as the heating or cooling rate in terms of . Realistic models of this type can be hard to construct (e.g., Bowers and Taylor, 1985), however, because the heating or cooling rates need to be balanced somehow with the rates of mass transfer. [Pg.13]

Is the assumed nature of equilibrium appropriate The modeler defines an equilibrium system that forms the core of a geochemical model, using one of the equilibrium concepts already described. The modeler needs to ask whether the reactions considered in an equilibrium system actually approach equilibrium. If not, it may be necessary to decouple redox reactions, suppress miner-... [Pg.25]

Most importantly, has the modeler conceptualized the reaction process correctly The modeler defines a reaction process on the basis of a concept of how the process occurs in nature. Many times the apparent failure of a calculation indicates a flawed concept of how the reaction occurs rather than error in a chemical analysis or the thermodynamic data. The failed calculation, in this case, is more useful than a successful one because it points out a basic error in the modeler s understanding. [Pg.26]

Furthermore, the SCOR-model defines five generic performance attributes to measure performance ... [Pg.15]

For n > 1, the segregated flow model provides the upper bound on conversion, and the maximum-mixedness model defines the lower bound. [Pg.504]

The attributes in a type model define which snapshots are legal. As shown in Figure 2.6, the course attribute of a session must link to a valid Course. A given snapshot need not depict all attributes of an object, so if you omit an attribute from a snapshot you have said nothing about its value. If you want the attribute to be unconnected, it must be marked with a null value. [Pg.83]

Model Defines the state of an object (or component) as a smaller and simpler set of attributes than the actual variables or fields used in the design or simpler than some other model that presents a more detailed view. How would you compute each abstract attribute from the data stored in the implementation, or from the more detailed attributes ... [Pg.242]

Diagrams and appearances The total model defined by a package is split across a number of diagrams. Each model element can have multiple appearances in different diagrams or in fragments of formal text. [Pg.315]

The primary deliverable is a type specification the system being developed specified as a type, with a type model (attributes and associations) and a set of operations specified against that type model. Defining the type involves identifying each action in which the system participates and specifying it as an operation on the type. The behavior can be described with state charts in addition to operation specifications and can be exercised with scenarios and snapshots. [Pg.542]

The tools we created in Chapter 3, Physical/Chemical Models, form the core of the fitting algorithms of this chapter. The model defines a mathematical function, either explicitly (e.g. first order kinetics) or implicitly (e.g. complex equilibria), which in turn is quantitatively described by one or several parameters. In many instances the function is based on such a physical model, e.g. the law of mass action. In other instances an empirical function is chosen because it is convenient (e.g. polynomials of any degree) or because it is a reasonable approximation (e.g. Gaussian functions and their linear combinations are used to represent spectral peaks). [Pg.101]

A number of other models for unstable conditions have been used, notably the formulations of O Brien (1970) and of Myrup and Ranzieri (1976). O Brien s model defines a cubic polynomial variation of above the surface layer. Boundary conditions are established by matching a similarity solution at the top of the surface layer and fixing profile gradients at z = L and Z. The expression for the diffusivity is... [Pg.279]

Exercise 6. Show that the equilibrium point of the model defined by Eq.(34) and the simplified model R given by Eq.(35), i.e. when the dynamics of the jacket is considered negligible, are the same. Deduce the Jacobian of the system (35) at the corresponding equilibrium point. Write a computer program to determine the eigenvalues of the linearized model R at the equilibrium point as a function of the dimensionless inlet flow 4 50. Values of the dimensionless parameters of the PI controller can be fixed at Ktd = 1-52 T2d = 5. The set point dimensionless temperature and the inlet coolant flow rate temperature are Xg = 0.0398, X40 = 0.0351 respectively. An appropriate value of dimensionless reference concentration is C g = 0.245. Does it exist some value of 2 50 for which the eigenvalues of the linearized system R at the equilibrium point are complex with zero real part Note that it is necessary to vary 2 50 from small to great values. Check the possibility to obtain similar results for the R model. [Pg.263]

It is interesting to point out that the regular behavior, where a steady state is reached by the reactor, can be investigated from the models defined by Eqs.(33) or (34), taking into account different values of the PI controllers. The values of Kvd and rid are chosen from the inequality ... [Pg.263]

Consider the R model defined by Eq.(43). In order to analyze the stability at the equilibrium point x2e, xse, xge), it is necessary to introduce the deviation variables given as ... [Pg.269]


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See also in sourсe #XX -- [ Pg.1461 ]

See also in sourсe #XX -- [ Pg.423 ]




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