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Variational equations

The equilibrium problem for a plate is formulated as some variational inequality. In this case equations (3.92)-(3.94) hold, generally speaking, only in the distribution sense. Alongside (3.95), other boundary conditions hold on the boundary F the form of these conditions is clarified in Section 3.3.3. To derive them, we require the existence of a smooth solution to the variational inequality in question. On the other hand, if we assume that a solution to (3.92)-(3.94) is sufficiently smooth, then the variational inequality is a consequence of equations (3.92)-(3.94) and the initial and boundary conditions. All these questions are discussed in Section 3.3.3. In Section 3.3.2 we prove an existence theorem for a solution to the variational equation and in Section 3.3.4 we establish some enhanced regularity properties for the solution near F. ... [Pg.200]

B) Variational Equations.—Consider again a dynamical system whose motion is specified by the differential equation... [Pg.344]

If one substitutes Eq. (6-37) into (6-36), and cancels out the terms with xi0, he obtains the variational equations... [Pg.344]

It is obvious that for xl0(t) one can take xJO(0) = 0, the position of equilibrium, in which case one can call xio(0) = 0 a constant or identically zero solution. In such a case, one can discuss the variational equations of singular points. [Pg.344]

Variational Equations of Singular Points.—One encounters often the differential equations of the form... [Pg.344]

Summing the question of the variational equations, one must say that in relatively simple systems with constant coefficients, there is no particular difficulty in carrying out these calculations. But in more... [Pg.345]

The method gives directly the stability in the large instead of the infinitesimal stability yielded by the variational equations. [Pg.349]

Dynamic programming, 305 Dynamical systems variational equations, 344 of singular points, 344 Djmamical variables characterizing a particle, 494 Dyson, F. J. 613 Dzyaloshinsky, /., 758... [Pg.773]

Variance, 269 of a distribution, 120 significance of, 123 of a Poisson distribution, 122 Variational equations of dynamical systems, 344 of singular points, 344 of systems with n variables, 345 Vector norm, 53 Vector operators, 394 Vector relations in particle collisions, 8 Vectors, characteristic, 67 Vertex, degree of, 258 Vertex, isolated, 256 Vidale, M. L., 265 Villars, P.,488 Von Neumann, J., 424 Von Neumann projection operators, 461... [Pg.785]

The kinetics of liberation of methanol were therefore recalculated taking into account the pH variations equation (1) could be rewritten replacing the concentration of OH ions by its expression as a function of the buffer. At each point the concentration of OH was calculated from the initial pH and the amount of reacted ester ... [Pg.606]

For a fixed external potential v(f), the ground-state electron density po satisfies the variational equation ... [Pg.161]

Start with the inverse variation equation, y = -y=. Replace the y with 9 and... [Pg.154]

Without using the detailed variational equations, a first hint can be obtained by applying the special polar part (B.47) of the generating function. A simple numerical analysis in the case = 2 and fm = 1 then yields the result qo/e — 1.6 according to conditions (B.70), the form (B.55), and expression (B.45). The corresponding extremum value should at least become somewhat lower, because the special function (B.47) is not likely to be that function that in a variational analysis should result in the lowest possible value of S and qo-... [Pg.74]

The difficulty lies in the nature of the functional itself. Up to this point, we have indicated that there are mappings from the density onto the Hamiltonian and the wave function, and hence the energy, but we have not suggested any mechanical means by which the density can be used as an argument in some general, characteristic variational equation, e.g., with terms along the lines of Eqs. (8.5) and (8.7), to determine the energy directly without recourse to the wave function. Such an approach first appeared in 1965. [Pg.254]

This linear equation for 80 can easily be solved when 0(t) is known. It is called the linearized or variational equation associated with (3.1). When it turns out that the solutions of (3.5) tend to zero as x->oo it follows that this particular solution 0(t) of (3.1) is stable for small perturbations, or locally stable . Clearly (3.5) cannot tell anything about global stability, i.e., the effect of large perturbations. One can only conclude from the local stability that 0(t) has a certain domain of attraction every solution starting inside this domain will tend to 0(t) for large t. In this chapter, however, we postulate (3.4), which guarantees global stability. [Pg.257]

These equations are again the same as the variational equations associated with the macroscopic equations (5.5). [Pg.265]

In fact, it is clear from fig. 34 that there is a larger domain of attraction Da such that every solution (t) with (0) in Da tends to (pa. Two macrostates starting at two neighboring points in Da — A a will first move away from each other, but subsequently approach one another again, until they both end up in (pa. This is clear from fig. 28 and also from the variational equation (X.3.5). Accordingly the fluctuations about such a (t) will first grow 0, but subsequently decrease again. Hence they can still be described by the -expansion and there is still a relation between macrostates and suitably chosen mesostates. [Pg.328]

The observed stereochemical variation (equation 8) was ascribed to the increasing intramolecular repulsive interactions, X X for example, when bulkier phosphines and heavier halides were introduced. Based on measurements of molecular species in solution, it was further proposed that a step involving dissociation into two dimeric molecules may occur for extremely bulky ligands.174... [Pg.798]

Second order variational equations and the strong maximum principle (with M.M. Denn). Chem. Eng. ScL 20,373-384 (1965). [Pg.458]

If we consider a cylindrical body as a typical example of an article produced by reactive processing, we can write the variational equation as follows ... [Pg.90]

Due to their higher flexibility and accuracy, Finite Elements Methods (FEMs) [5] are often preferred to numerical methods their basic concept consists first of all in establishing a weak variational formulation of the mathematical problem the second step is to introduce the concept of shape functions that are defined into small sub-regions of the domain (see also Chapter 3). Finally, the variational equations are discretised and form a linear system where the unknowns are the coefficients in the linear combination. [Pg.186]

Response Surface Methodology (RSM) is a statistical method which uses quantitative data from appropriately designed experiments to determine and simultaneously solve multi-variate equations (3). In this technique regression analysis is performed on the data to provide an equation or mathematical model. Mathematical models are empirically derived equations which best express the changes in measured response to the planned systematic... [Pg.217]

The variational equations have two solutions for which the common relationships are... [Pg.58]

Another solution of the variational equations allows to describe a nonuniform state ... [Pg.58]

Generalized momenta are defined by pk = and generalized forces are defined by Qk = f - When applied using t as the independent variable, Euler s variational equation for the action integral / takes the form of Lagrange s equations of motion... [Pg.12]


See other pages where Variational equations is mentioned: [Pg.346]    [Pg.370]    [Pg.67]    [Pg.230]    [Pg.322]    [Pg.286]    [Pg.287]    [Pg.289]    [Pg.293]    [Pg.39]    [Pg.110]    [Pg.345]    [Pg.153]    [Pg.153]    [Pg.153]    [Pg.154]    [Pg.260]    [Pg.345]    [Pg.330]    [Pg.230]    [Pg.238]    [Pg.246]    [Pg.314]    [Pg.315]   
See also in sourсe #XX -- [ Pg.257 , Pg.265 , Pg.345 ]

See also in sourсe #XX -- [ Pg.46 , Pg.47 , Pg.48 , Pg.49 , Pg.50 , Pg.51 , Pg.52 , Pg.53 , Pg.54 , Pg.55 , Pg.59 , Pg.67 , Pg.68 , Pg.133 ]

See also in sourсe #XX -- [ Pg.540 ]

See also in sourсe #XX -- [ Pg.2 , Pg.91 , Pg.92 , Pg.194 ]




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