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Discrete form

The diserete solution of the matrix Rieeati equation solves reeursively for K and P in reverse time, eommeneing at the terminal time, where [Pg.276]

As k is increased from 0 to A — 1, the algorithm proceeds in reverse time. When run in forward-time, the optimal control at step k is [Pg.277]

The boundary condition is specified at the terminal time (/c = 0), where [Pg.277]

The reverse-time recursive process can commence with P(A) = 0 or alternatively, with P(A - 1) = TQ. [Pg.277]

Since P is symmetric, p2 = pn- Equation (9.37) can be expressed as four simultaneous equations [Pg.278]


The use of selectively reduced integration to obtain accurate non-trivial solutions for incompressible flow problems by the continuous penalty method is not robust and failure may occur. An alternative method called the discrete penalty technique was therefore developed. In this technique separate discretizations for the equation of motion and the penalty relationship (3.6) are first obtained and then the pressure in the equation of motion is substituted using these discretized forms. Finite elements used in conjunction with the discrete penalty scheme must provide appropriate interpolation orders for velocity and pressure to satisfy the BB condition. This is in contrast to the continuous penalty method in which the satisfaction of the stability condition is achieved indirectly through... [Pg.76]

The well-known inaccuracy of numerical differentiation precludes the direct calculation of pressure by the insertion of the computed velocity field into Equation (3.6). This problem is, however, very effectively resolved using the following variational recovery method Consider the discretized form of Equation (3.6) given as... [Pg.77]

Several discrete forms of the conservation of momentum equation, (9.3), can be derived, depending on the type of mesh and underlying assumptions. As an example, assume the equation will be solved on staggered spatial and temporal meshes, in two dimensions, in rectangular geometry, and with the velocities located at the nodes. Assume one quarter of the mass from each adjacent element is associated with the staggered element as shown in Fig. 9.11. [Pg.333]

The existence of unbalance in a rotor system may be in continuous form or discrete form, as shown in Figure 17-2. Ascertaining an exact distribution is an extremely difficult, if not impossible, task by today s techniques. [Pg.587]

F(r) and G(T) are the discrete transition and controi matrices and are obtained by converting the matrices in the continuous equation (9.49) into discrete form using equations (8.78) and (8.80). [Pg.282]

Script file examp77.m plots the closed-loop step responses of both the continuous system and discrete system (see Figure 7.21). In the latter case the plant pulse transfer function uses zoh, and the compensator is converted into discrete form using... [Pg.399]

Given a real-valued sequence (Jq, Ci,. ..,(T v-i, the the correlation function R t) and Fourier Transformation may be defined in both a continuous and discrete form ... [Pg.304]

We give both forms here because, depending on the problem, either of the two forms may yield a simpler answer. Although the discrete form may appear a-priori to be the natural choice, for example, its discrete nature actually introduces some spurious periodicity into the resulting power spectra, thus washing away some of its characteristic features. We therefore follow Li [H87] in working mainly with the continuous forms of R t) and... [Pg.305]

Although each form of concentration cell may be considered a discrete form of corrosion, in practice, more than one type may occur simultaneously. These forms of corrosion are all characterized by localized differences in concentration of hydrogen, oxygen, chloride, sulfate, and other minerals, but especially oxygen (producing the so-called differential oxygen concentration cell, or differential-aeration cell). The basic mechanisms surrounding each of these specific forms of concentration cell corrosion are discussed next. [Pg.246]

Direct inversions of the concentration distribution profiles to obtain molecular weight distribution information are generally impossible because of comphcations involving non-ideality. Successful attempts have been given but only for simple discrete forms of polydispersity (two to three macromolecular species [93]). [Pg.234]

In numerical analysis, both functions of normal surface deformation and pressure distribution have to be discretized in a space domain over U grid points for a line load, or grid points for two-dimensional distributed load. As an example, the deformation for line loading can be rewritten in discrete form as follows ... [Pg.122]

In Eq (25), the integration kernel function K x)= rr x is smooth everywhere except the singularity point (x = 0). In a numerical analysis, the integration has to be evaluated in discrete form over a grid with the mesh size h... [Pg.123]

If a coarse grid with a mesh size H H=lh, for example) is employed to evaluate the same integration (25), its discrete form can be written as... [Pg.123]

Two different approaehes to this problem will be described in this work. They are based in quite different philosophies, but both are aimed at determining the RDM without a previous knowledge of the WF. Another common feature of these two approaches is that they both employ the discrete Matrix representation of the Contraction Mapping (MCM) [17,18]. Applying this MCM is the alternative, in discrete form, to integrating with respect to a set of electron variables and it is a much simpler tool to use. [Pg.56]

Using Eq. (4.1.13), the estimation problem is cast in discrete form as the determination of the coefficients c = [c1 . .., cns] that minimize the quadratic performance index ... [Pg.366]

This expression is the discrete form of the convolution integral defined in Eq. (11-13). [Pg.172]

Later, Kuppermann and Belford (1962a, b) initiated computer-based numerical solution of (7.1), giving the space-time variation of the species concentrations from these, the survival probability at a given time may be obtained by numerical integration over space. Since then, this method has been vigorously followed by others. John (1952) has discussed the convergence requirement for the discretized form of (7.1), which must be used in computers this turns out to be AT/(Ap)2normalized forms of r and t. Often, Ar/(Ap)2 = 1/6 is used to ensure better convergence. Of course, any procedure requires a reaction scheme, values of diffusion and rate coefficients, and a statement about initial number of species and their distribution in space (vide infra). [Pg.200]

The fact that the observed electrochemistry could be explained in terms of two overlapping but discrete isotherms was taken as strong evidence for the existence of two discrete forms of H,d. ... [Pg.243]

Unlike the PEG molecules formed from anionic polymerization techniques, there now exist highly discrete forms of the polymer made by controlled addition of small PEG units to create chains of exacting molecular size. These discrete PEGs have a single molecular weight and do not display the polydispersity of the traditional PEG polymers. See Chapter 18 for a complete discussion of discrete PEG-based reagents and their applications. [Pg.937]

In the remainder of this chapter, for simplicity, we use a discrete form for the PSD given by the fraction of a particular size R in the solid feed. For identical particles of the same density, this is FBg(R)IFBo, the ratio of molar, or mass, flow rates. The outer integral in equation 22.2-3 then becomes a summation, and the equation may be rewritten as ... [Pg.556]

However, if a taxon underlies extreme dissociative experiences it makes our classification process much easier because the existence of this taxon implies not only that there is a more severe form but also that there is a discrete form. The discreteness of this entity suggests there is a qualitative difference, perhaps with a different etiology, course, and treatment. These issues are unknown initially but form an important starting point for future work. [Pg.13]

Keeping only the accumulation and spatial-transport terms, the FV code solves a discretized form of... [Pg.351]

Although it is not known whether this is a dynamic or a static disorder, it is clear from Fig. 2 that the two units result from an inversion at the central carbon, followed by a 180° rotation around the P1-C2 bond. The observation that this carbene has difficulty in maintaining one discrete form in the solid state could well be consistent with the low value for the inversion barrier at carbon, calculated by Hegarty et al.13 (see Section II). [Pg.186]

There is a special type of controller, called a Smith predictor or deadtime compensator, that can be applied in either continuous or discrete form. It is basically a special type of model-based controller, in the same family as IMC. Figure 20.6a gives a sketch of a conventional feedback control system. Let s break up the total openloop process into the portion without any deadtime G j,(s) nd deadtime e... [Pg.703]


See other pages where Discrete form is mentioned: [Pg.269]    [Pg.74]    [Pg.103]    [Pg.330]    [Pg.331]    [Pg.336]    [Pg.336]    [Pg.276]    [Pg.281]    [Pg.679]    [Pg.695]    [Pg.696]    [Pg.714]    [Pg.688]    [Pg.398]    [Pg.402]    [Pg.567]    [Pg.100]    [Pg.443]    [Pg.121]    [Pg.461]    [Pg.559]    [Pg.597]    [Pg.450]    [Pg.251]   


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