Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Infinitesimal parameter

Both of these transformations can be formulated in terms of a common set of infinitesimal parameters 8oj, i.e. [Pg.19]

Let the system be initially in the stationary state (Y, Z) and then escape this state. The system evolution ( phase trajectories ) near the stationary state (Y, Z) can be determined with an assumption that Y = Y + y and Z = Z + z by linearizing equation (3.26) for infinitesimal parameters y and z into the set of characteristic equations... [Pg.153]

In this sense it will be considered an infinitesimal displacement of the Fock subspace of N particles to the one of N- 1) with the aid of the anni-hilation operator and through an infinitesimal parameter, X. [Pg.183]

This model of cavitation development allows explaining the above-mentioned experimental facts and essentially simplifies the problem of constracting a mathematical model of the process. In the author proposed a real liquid to be considered as a two-phase medium, in spite of the infinitesimal parameters of its inhomogeneity, and to describe the cavitation processes with the use of the system of Iordansky equations for bubbly medium. In the... [Pg.401]

The brute force method depends on a systematic variation of all involved coefficients over a reasonable parameter space. The combination yielding the lowest goodness-of-fit measure is picked as the center for a further round with a finer raster of coefficient variation. This sequence of events is repeated until further refinement will only infinitesimally improve the goodness-of-fit measure. This approach can be very time-consuming and produce reams of paper, but if carefully implemented, the global minimum will not be missed, cf. Figures 3.4 and 4.4. [Pg.159]

The generators of a Lie group are defined by considering elements infinitesimally close to the identity element. The operator T(a)x —t x takes variables of space from their initial values x to final values x as a function of the parameter a. The gradual shift of the space variables as the parameters vary continuously from their initial values a = 0 may be used to introduce the concept of infinitesimal transformation associated with an infinitesimal operator P. Since the transformation with parameter a takes x to x the neighbouring parameter value a + da will take the variables x to x + dx, since x is an analytical function of a. However, some parameter value da very close to zero (i.e. the identity) may also be found to take x to x + dx. Two alternative paths from x to x + dx therefore exist, symbolized by... [Pg.86]

For a problem for which we cannot obtain an analytical solution, you need to determine sensitivities numerically. You compute (1) the cost for the base case, that is, for a specified value of a parameter (2) change each parameter separately (one at a time) by some arbitrarily small value, such as plus 1 percent or 10 percent, and then calculate the new cost. You might repeat the procedure for minus 1 percent or 10 percent. The variation of the parameter, of course, can be made arbitrarily small to approximate a differential however, when the change approaches an infinitesimal value, the numerical error engendered may confound the calculations. [Pg.26]

Accordingly, let us assume that the entries in the matrices A and C are either zeros or arbitrary nonzero parameters. For nonlinear systems, their description will be accurate in an infinitesimal region around the point of linearization. Many of the elements of matrices A and C will vary from one linearization point to another, and some elements will always be zero. [Pg.37]

Our problem has four parts. First, we must determine the rate law for an infinitesimal length of catalyst bed. Second, the resulting equation must be integrated over the length of the bed. Third, the values of certain of the system parameters must be determined using the integrated equation and experimental conversions. Finally, the site density is determined from the values of these parameters. [Pg.114]

The answer is yes, in a very general way, as has been discussed before [62,63]. Consider any parameter in the external potential, called y. For definiteness, we choose the internuclear separation in a diatomic molecule. Then the exchange-correlation energy depends parametrically on this quantity. Now imagine making an infinitesimal change in y. The differential change in is... [Pg.20]

We now briefly review the derivation of the fast-forward driving potential that accelerates an adiabatic process [15]. Consider a system with the potential energy function Vq = o(r, a(O), in which R (t) = R, -I- et, is a parameter with infinitesimal rate of change, that is, e 1. We take the wave function of the system to be... [Pg.59]

Relation to the variational method. As will be seen from our treatment of p.m. on the basis of the variational method, p.m. is in substance only a special case of the variational method. Moreover it is rather of a formal character because it regards the parameter k as infinitesimal, while in practical problems k is always finite if small. From this point of view, p.m. is only a convenient method for supplying ap-... [Pg.50]

As indicated, a single mean-field parameter amf is included as the proportionality factor. It is noteworthy that the numerical value of amf is unimportant to the condensation phenomenon itself, so that even an infinitesimally small value (e.g., of order 10-6 a.u.), is sufficient to reward thermodynamic condensation and yield an alternative phase of greatly reduced V under appropriate conditions of temperature and pressure. [Pg.458]

Unit tensors are especially important for group-theoretical methods of studying the lN configuration. We can express the infinitesimal operators of the groups [10, 24, 98], the parameters of irreducible representations of which are applied to achieve an additional classification of states of a shell of equivalent electrons, in terms of them. [Pg.126]

Given a model, the analysis can be performed mathematically. A finite element computer code (Ref 38) for the analysis of finite or infinitesimal strains is now available, modified (Ref 68) to account for shock induced stresses, temp rise (by the assumption of a constant Grueneisen parameter), heat generated by the decompn of the expl and transient heat transfer. Later in this article we report an empirical treatment of propint initiation data (Fig 4)-Analy tic ally obtained data are in fair agreement with exptl results so that further effort along these lines appears justified (Ref 68)... [Pg.250]

We must note also a second important restriction of the continuous chain model. As we will see. by construction it deals with infinitely long chains n — oo. infinitesimally close to the -point , 5C — 0. Thus naive two parameter theory is valid only very close to the -temperature. In later chapters we will see how further renormalization leads to a theory of excluded volume effects valid for all /%, > 0. [Pg.105]


See other pages where Infinitesimal parameter is mentioned: [Pg.158]    [Pg.555]    [Pg.158]    [Pg.366]    [Pg.25]    [Pg.26]    [Pg.38]    [Pg.38]    [Pg.39]    [Pg.24]    [Pg.66]    [Pg.158]    [Pg.555]    [Pg.158]    [Pg.366]    [Pg.25]    [Pg.26]    [Pg.38]    [Pg.38]    [Pg.39]    [Pg.24]    [Pg.66]    [Pg.1308]    [Pg.226]    [Pg.502]    [Pg.324]    [Pg.330]    [Pg.205]    [Pg.198]    [Pg.221]    [Pg.330]    [Pg.610]    [Pg.56]    [Pg.132]    [Pg.320]    [Pg.79]    [Pg.602]    [Pg.201]    [Pg.329]    [Pg.44]    [Pg.596]    [Pg.288]    [Pg.109]    [Pg.181]    [Pg.98]   
See also in sourсe #XX -- [ Pg.38 , Pg.39 ]




SEARCH



Infinitesimal

© 2024 chempedia.info