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Discrete also

The types of product that fell within the scope of Council Regulation (EEC) No. 2309/93 as amended, were set out in the Annex to that Regulation. Eor medicinal products falling within the scope of Part A of the Annex, applicants were obliged to use the centralised procedure and send their application to the EMEA. Eor those falling within the scope of Part B of the Annex, applicants may, at their discretion, also use the centralised procedure. Unlike the previous concertation procedure (Council Directive... [Pg.515]

Xe 0,0.00001,0.0001,0.001,0.01,0.1,1.0, or can be represented using any other mathematical scheme of choice. This discretization depends partly on the resolution at which the binary combination needs to be studied and partly on the dependence of activity on composition. Any a priori information on dependence of activity on composition of the components in the binary mixture can be used to better design the composition intervals of XA or XB. As we know that SCOPE formulations occur in a very narrow range of chemical compositions, a finer discretization is preferred. Finer discretization also implies increased number of formulations. [Pg.254]

In order to develop the numerical analogs of the electromagnetic field integral representations, we have to discretize, also, the field components and the Green s tensors within the anomalous domain D of integration. We can treat all integral representations, considered in this chapter, as operators acting on the vector functions, x,... [Pg.269]

Discretization also refers to the process of decomposing a computational domain into smaller subdomains frequently called cells or elements, within which simple approximate functions can be used to define physical unknown variables. The discretized domain is frequently called a computational grid or mesh. [Pg.607]

In the representation of the local squeeze velocity, an embedded Tr.ipezoidal rule was employed for the pressure values from the current time step. The accuracy of this representation was influenced by the spacing of the discrete pressure distribution which was not controlled within the DGEAR library routine. Thus, reliability checks had to be performed by varying the level of discretization. The level of discretization also influenced the accuracy of the calculated load. The reliability of the part of the solution which was controlled by DGEAR had checks made by varying the allowable local truncation error within DGEAR. [Pg.372]

Discretizing the partial differential evolution equations essentially makes the radius constant in each equation, by converting than to ordinary differential equations, with one equation for each radius. However, discretization also allows the integro-diffaential components of the equations to be expressed as finite difference approximations in equally spaced radius incronents (Ar). [Pg.372]

Flowever, we have also seen that some of the properties of quantum spectra are mtrinsically non-classical, apart from the discreteness of qiiantnm states and energy levels implied by the very existence of quanta. An example is the splitting of the local mode doublets, which was ascribed to dynamical tiumelling, i.e. processes which classically are forbidden. We can ask if non-classical effects are ubiquitous in spectra and, if so, are there manifestations accessible to observation other than those we have encountered so far If there are such manifestations, it seems likely that they will constitute subtle peculiarities m spectral patterns, whose discennnent and interpretation will be an important challenge. [Pg.76]

The set of microstates of a finite system in quantum statistical mechanics is a finite, discrete denumerable set of quantum states each characterized by an appropriate collection of quantum numbers. In classical statistical mechanics, the set of microstates fonn a continuous (and therefore infinite) set of points in f space (also called phase space). [Pg.382]

The solution Xh(t) of the linearized equations of motion can be solved by standard NM techniques or, alternatively, by explicit integration. We have experimented with both and found the second approach to be far more efficient and to work equally well. Its handling of the random force discretization is also more straightforward (see below). For completeness, we describe both approaches here. [Pg.247]

Hence, we use the trajectory that was obtained by numerical means to estimate the accuracy of the solution. Of course, the smaller the time step is, the smaller is the variance, and the probability distribution of errors becomes narrower and concentrates around zero. Note also that the Jacobian of transformation from e to must be such that log[J] is independent of X at the limit of e — 0. Similarly to the discussion on the Brownian particle we consider the Ito Calculus [10-12] by a specific choice of the discrete time... [Pg.269]

Another option is a q,p) = p and b q,p) = VU q). This guarantees that we are discretizing a pure index-2 DAE for which A is well-defined. But for this choice we observed severe difficulties with Newton s method, where a step-size smaller even than what is required by explicit methods is needed to obtain convergence. In fact, it can be shown that when the linear harmonic oscillator is cast into such a projected DAE, the linearized problem can easily become unstable for k > . Another way is to check the conditions of the Newton-Kantorovich Theorem, which guarantees convergence of the Newton method. These conditions are also found to be satisfied only for a very small step size k, if is small. [Pg.285]

The form of the Hamiltonian impedes efficient symplectic discretization. While symplectic discretization of the general constrained Hamiltonian system is possible using, e.g., the methods of Jay [19], these methods will require the solution of a nontrivial nonlinear system of equations at each step which can be quite costly. An alternative approach is described in [10] ( impetus-striction ) which essentially converts the Lagrange multiplier for the constraint to a differential equation before solving the entire system with implicit midpoint this method also appears to be quite costly on a per-step basis. [Pg.355]

Let us first define the information content per object. A (discrete) system can be split into classes of equivalence, whose number can vary from 1 to n, where n is the number of the elements (objects) in the system. No element can belong simultaneously to more than one class. Therefore, the information content (JQ of the system is additive, at least class-wise. This means that the information content of the system is the sum of the information contents of the classes. The IC of a class can be given by Eq. (2), where h is the number of elements in the ith class. (Recall, also, that log (x) = -log (l/x)). [Pg.212]

In practice, in order to maintain the symmetry of elemental coefficient matrices, some of the first order derivatives in the discretized equations may also be integrated by parts. [Pg.78]

The first finite element schemes for differential viscoelastic models that yielded numerically stable results for non-zero Weissenberg numbers appeared less than two decades ago. These schemes were later improved and shown that for some benchmark viscoelastic problems, such as flow through a two-dimensional section with an abrupt contraction (usually a width reduction of four to one), they can generate simulations that were qualitatively comparable with the experimental evidence. A notable example was the coupled scheme developed by Marchal and Crochet (1987) for the solution of Maxwell and Oldroyd constitutive equations. To achieve stability they used element subdivision for the stress approximations and applied inconsistent streamline upwinding to the stress terms in the discretized equations. In another attempt, Luo and Tanner (1989) developed a typical decoupled scheme that started with the solution of the constitutive equation for a fixed-flow field (e.g. obtained by initially assuming non-elastic fluid behaviour). The extra stress found at this step was subsequently inserted into the equation of motion as a pseudo-body force and the flow field was updated. These authors also used inconsistent streamline upwinding to maintain the stability of the scheme. [Pg.81]

The outlined scheme is shown to yield stable solutions for non-zero Weissenberg number flows in a number of benchmark problems (Swarbric and Nassehi, 1992b). However, the extension of this scheme to more complex problems may involve modifications such as increasing of elemental subdivisions for stress calculations from 3 x 3 to 9 x 9 and/or the discretization of the stress field by biquadratic rather than bi-linear sub-elements. It should also be noted that satisfaction of the BB condition in viscoelastic flow simulations that use mixed formulations is not as clear as the case of purely viscous regimes. [Pg.86]

Extension of the streamline Petrov -Galerkin method to transient heat transport problems by a space-time least-squares procedure is reported by Nguen and Reynen (1984). The close relationship between SUPG and the least-squares finite element discretizations is discussed in Chapter 4. An analogous transient upwinding scheme, based on the previously described 0 time-stepping technique, can also be developed (Zienkiewicz and Taylor, 1994). [Pg.92]


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Discrete (also momentum equation

Discrete (also solution

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