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Exact averages

For this algorithm, one can prove that detailed balance is guaranteed and the exact average of any configuration-dependent property over the accessible space is obtained. Two key issues determine the detailed balance. The first is the fact that the trial probability to pick the displacement vector Dfc to go from the fcth to the Zth e-sphere equals the trial probability to pick the displacement vector D fc for the reverse step. The second issue is that the trial probability for a local MC step that moves the walker from a point inside an e-sphere to a point outside that sphere is the same as for the reverse move i.e., (1 - / ) times what it would be in a walk restricted to local moves. [Pg.292]

The virtue of the RIS approach lies in the form of Eq. (3) A global exact average (subject, of course to the simplification of factorizability as set forth in Eq. (l),Eq. (2), and Eq. (3)) over a very large number of chain conformations can be obtained with a simple matrix product, calculable with a trivial computational effort that is provided by any modern Personal Computer. And since each U,- and each F,- can be defined separately, practically any chemical structure will yield to an RIS treatment. [Pg.4]

We assume that the rate constant is calculated according to transition-state theory. Calculate the barrier height Eq (in the unit kJ/mol), using Ea and the exact average vibrational energies. [Pg.220]

G (t) allows an exact average over the position of the initial... [Pg.328]

Koplik et al. (1988) considered flow rates in percolation networks from zero (pure diffusion) to extremely high (the convective limit where the average transit time varies linearly with 1/v). The results obtained for many network realizations were averaged. In the case of 2 x 2 and 3x3 network lattices, all possible configurations could be evaluated and hence, the exact averaged transit time moments could be determined. These authors found that anomalous diffusion occurs on networks at the percolation threshold at zero flow. Hence, the CDE does not apply in this case. Koplik et al. (1988) demonstrate that the moments of the transit time distribution for transport near the percolation threshold scale universally. [Pg.124]

However, whenever measuring an atmospheric substance, p and T must be co-measured to allow standard recalculations for exact averaging and intercomparisons. [Pg.358]

The normalization factor is M - 1 when the average is calculated from eq. (17.1) if the exact average is known from another source, the normalization is just N. For large samples the difference between the two is minute and the normalization is often taken as N. The square root of the variance (i.e. a) is called the standard deviation.The above two data sets have standard deviations of 1.6 and 0.2, clearly showing that the first set contains elements further from the mean than the second. [Pg.549]

We And that truncating the update equations to 0(s ) is sufficient to explicitly resolve the leading order behavior of the error for these discretization schemes, and we give the differences between observed numerical averages and exact averages below ... [Pg.280]

The third term, C, is a measure of the resistance to mass transfer between the stationary phase and the mobile phase. To a first approximation, it is inversely proportional to the diffusion coefficient. Dm, and directly proportional to the second power of the distance a solute molecule should travel from the mobile phase to reach the interaction site in the particle. For a totally porous particle, this distance is proportional to the mean particle diameter, d. More exactly, average pore depth should be used instead, but this quantity is difficult to determine. [Pg.1298]

The results of the inverse problem are recounted later (i) with no added error, and (ii) with 10% random error to the exact average particle size as it evolves through time as well as to the self-similar data. [Pg.249]

The exact average heat flux is 0.542 while the approximate MWR value is 0.471. This represents a 13 percent error, which is quite acceptable considering that this is just a first-order approximation N = 1). [Pg.413]

Again, k cancels out in these equations. Once the distributions are known, the exact averages may be calculated by the techniques in Section 5.4. For example, insertion of Equation 5.47 into Equations 5.23 and 5.26 gives Equations 5.41 and 5.42. [Pg.85]

Hazard indicators. - The 7 casters who took part in our study gave us an average of 11-12 hazard indicators in the course of their interviews which could be rated using our scheme for analysis. The apprentice who had only been working at this work site for 14 days supplied us with 12.1 hazard indicators, almost the exact average (for understanding what a hazard indicator is conceived of, see p. 83 ff.). [Pg.164]

The difference between the approximated time using (3.2.12) and the exact average delivery time is in all examples between 2 and 9 pooent, whereas the shadow-approximation leads m a diffoence between 15 and 36 percent, always in the opposite direction. From this random set of examples, we can already conclude that by using E as an approximation, we can estimate the delivery times quite well. Another important aspect is that the value of several cost functions containing the weighted sum of the delivery times of the different types could be estimated very well by the approximated... [Pg.28]

In order to define a reasonable estimator for the statistical error, it is necessary to start from the assumption that an infinite number of independent samples k has been generated. In this case, the distribution of the estimates is Gaussian, according to the central limit theorem of uncorrelated samples. The exact average of the estimates is then given by O). It immediately follows that... [Pg.84]

We have already found that the estimation of O is bias-free, i.e., its exact average (O) is identical with O) [see Eq, (4,3)]. However, we have also convinced ourselves that variances of sampled data are not free of bias. Combining Eqs. (4,10) and (4.11), we consequently find that the expected value of the simplest nonlinear function of O, AO) = o ... [Pg.90]


See other pages where Exact averages is mentioned: [Pg.131]    [Pg.104]    [Pg.289]    [Pg.4]    [Pg.117]    [Pg.7]    [Pg.768]    [Pg.131]    [Pg.174]    [Pg.70]    [Pg.293]    [Pg.1487]    [Pg.249]    [Pg.170]    [Pg.461]    [Pg.626]    [Pg.376]    [Pg.77]    [Pg.84]    [Pg.86]   
See also in sourсe #XX -- [ Pg.277 ]




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