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Successive approximations of the

After all, even in the first case we deal with the interaction of an electron belonging to the gas particle with all the electrons of the crystal. However, this formulation of the problem already represents a second step in the successive approximations of the surface interaction. It seems that this more or less exact formulation will have to be considered until the theoretical methods are available to describe the behavior both of the polyatomic molecules and the metal crystal separately, starting from the first principles. In other words, a crude model of the metal, as described earlier, constructed without taking into account the chemical reactivity of the surface, would be in this general approach (in the contemporary state of matter) combined with a relatively precise model of the polyatomic molecule (the adequacy of which has been proved in the reactivity calculations of the homogeneous reactions). [Pg.53]

Table IV. Successive Approximations of the Scaling Parameters s and a for the Distribution Data of Table III According to Equation 30... Table IV. Successive Approximations of the Scaling Parameters s and a for the Distribution Data of Table III According to Equation 30...
The initial function fi is chosen equal to h. The functions f are successive approximations of the function f we are looking for. Therefore, this method consists of iteratively calculating these fimctions f . Based on the relations we have just given, we have ... [Pg.243]

The first known solution was that of Schwarzschild that provides the origin of the notion of a black hole. Let us also mention the Kerr solution, plane gravitational waves, the general first order solution, the successive approximations of the two black hole problem hundreds of rigourous solutions are known today. [Pg.325]

Using this iteratively from a known pose and updating the obtained position by the forward conversion, /r, a successive approximation of the exact path to a programmed point can be obtained. It assumed that the initial pose is... [Pg.1073]

A solution of the now complete set of nonlinear equations was achieved by developing an iterative scheme based on the successive approximation of the function Q(x). The method was programmed in Fortran 77 on the Amdahl computer at Leeds University to give the following results. [Pg.193]

Fig. 1. Approximate cross section of a tubule with scroll helicity. The distance d between successive rolls of the spiral is assumed to be constant,... Fig. 1. Approximate cross section of a tubule with scroll helicity. The distance d between successive rolls of the spiral is assumed to be constant,...
The method of successive approximations. In the first approximation, you ignored the x in the denominator of the equation. This time, you use the approximate... [Pg.365]

Because of the convenient mathematical characteristics of the x -value (it is additive), it is also used to monitor the fit of a model to experimental data in this application the fitted model Y - ABS(/(x,. ..)) replaces the expected probability increment ACP (see Eq. 1.7) and the measured value y, replaces the observed frequency. Comparisons are only carried out between successive iterations of the optimization routine (e.g. a simplex-program), so that critical X -values need not be used. For example, a mixed logarithmic/exponential function Y=Al LOG(A2 + EXP(X - A3)) is to be fitted to the data tabulated below do the proposed sets of coefficients improve the fit The conclusion is that the new coefficients are indeed better. The y-column shows the values actually measured, while the T-columns give the model estimates for the coefficients A1,A2, and A3. The x -columns are calculated as (y- Y) h- Y. The fact that the sums over these terms, 4.783,2.616, and 0.307 decrease for successive approximations means that the coefficient set 6.499... yields a better approximation than either the initial or the first proposed set. If the x sum, e.g., 0.307,... [Pg.79]

All these steps are bnilt into an iterative procednre whose success pivots on the approximation of the higher order RDM s in terms of the 2-RDM. This important part of the method will be addressed in the next section. [Pg.68]

A simple and successful approximation for the excess free energy functional is to first assume that the excess free energy functional is only a functional of the average site density profile, denoted p(r), and then invoke standard approximations, similar to those used for simple liquids, for FEX- With a judicious choice of Fkx[Pm], the free energy functional can be exactly decomposed as... [Pg.123]

A possible computational strategy is to calculate Xs(r O first using the standard sum-over states formula (Equation 24.80). Equation 24.75 can be used next to generate successive Born approximations of the functions f (r). For instance, the first Bom approximation would be... [Pg.352]

The commercially available software (Maximum Entropy Data Consultant Ltd, Cambridge, UK) allows reconstruction of the distribution a.(z) (or f(z)) which has the maximal entropy S subject to the constraint of the chi-squared value. The quantified version of this software has a full Bayesian approach and includes a precise statement of the accuracy of quantities of interest, i.e. position, surface and broadness of peaks in the distribution. The distributions are recovered by using an automatic stopping criterion for successive iterates, which is based on a Gaussian approximation of the likelihood. [Pg.189]


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The Approximations

The Method of Successive Approximations

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