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Expected values, use

We start by considering an arbitrary measurable10 one-point11 scalar function of the random fields U and 0 Q U, 0). Note that, based on this definition, Q is also a random field parameterized by x and t. For each realization of a turbulent flow, Q will be different, and we can define its expected value using the probability distribution for the ensemble of realizations.12 Nevertheless, the expected value of the convected derivative of Q can be expressed in terms of partial derivatives of the one-point joint velocity, composition PDF 13... [Pg.264]

Note that the spatial dependence of the mixing time enters the deterministic error through the expected value. Using (6.231), we can rewrite (6.232) as... [Pg.324]

A further issue arises in the Cl solvation models, because Cl wavefunction is not completely variational (the orbital variational parameter have a fixed value during the Cl coefficient optimization). In contrast with completely variational methods (HF/MFSCF), the Cl approach presents two nonequivalent ways of evaluating the value of a first-order observable, such as the electronic density of the nonlinear term of the effective Hamiltonian (Equation 1.107). The first approach (the so called unrelaxed density method) evaluates the electronic density as an expectation value using the Cl wavefunction coefficients. In contrast, the second approach, the so-called relaxed density method, evaluates the electronic density as a derivative of the free-energy functional [18], As a consequence, there should be two nonequivalent approaches to the calculation of the solvent reaction field induced by the molecular solute. The unrelaxed density approach is by far the simplest to implement and all the Cl solvation models described above have been based on this method. [Pg.89]

We evaluate the time-dependent expectation values using the time-dependent wave-function, O >,... [Pg.545]

Expected values using a third generation immunochemi-luminometric assay are as follows " ... [Pg.2068]

The reference intervals for T3 may vary froin one procedure and reference population to another. Each laboratory should establish its own reference intervals. Expected values using an RIA method are as foUows. ... [Pg.2072]

At any level, a calculation of first-order properties simply reduces to a determination of an expectation value using the wave function P. For example, the electric dipole moment is calculated as... [Pg.571]

This adiabatic connection formula [49] is very useful for calculating expectation values using the interaction picture. In the corresponding Gellman-law expression in Hilbert space [50] there is an extra denominator that takes care of the phase of the wavefunction. [Pg.377]

Using these tests implies comparing scores observed to a standard, an expected value. Ideally that would be to the same subject which is rarely possible, although it works for before and after exposures of workers. The next best comparisons are to suitable unexposed normal subjects who can be called controls. We developed over several years a national sample of unexposed people, tested their performance and calculated expected values using prediction equations with coefficients for age, sex, education and other factors such as height and weight that affected some tests. Thus individual observed values for each subject are compared to predicted values (observed/predicted xlOO) equal percent predicted. Frequently, we needed to be sure that comparison groups of apparently unexposed control people were normal because adverse effects are widespread. Next from the standard deviations... [Pg.1408]

With this expansion for the wave function, the expectation value using the electronic Hamiltonian (Eq. [2]) can be calculated using the Slater-Condon rules. The result is (in Dirac notation) ... [Pg.5]

If the whole range is to be represented by just one value (which of course gives no indication of the range of uncertainty), then the expectation value is used ... [Pg.163]

Because this current is given by a conmuitator, its equilibrium expectation value is zero. Using die first expression in (A3.2.43). the response function is given by... [Pg.712]

In this approach [ ], the LCAO-MO coefficients are detemiined first via a smgle-configuration SCF calculation or an MCSCF calculation using a small number of CSFs. The Cj coefficients are subsequently detemiined by making the expectation value ( P // T ) / ( FIT ) stationary. [Pg.2176]

One of the discussion points is how the quantum system reacts back on the classical d.o.f., i.e., how the forces on the classical system should be derived from the quantum system. One can use the gradient of the effective energy, i.e., of the expectation value of the total energy... [Pg.16]

Equilibrium average properties are calculated using a statistical weighting of the probability Pq(r) of Eq. (3) raised to the power of q as required by the generalized statistical mechanics. The so-called q-expectation value is written... [Pg.199]

For certain values of q and a harmonic potential, the distribution pq (F) can have infinite variance and higher moments. This fact has motivated the use of the g-expectation value to compute the average of an observable A... [Pg.201]

This definition is based on and proportional to the g-expectation value. However, it is more useful since it is not necessary to evaluate the partition function to compute an average. [Pg.201]

If the function greater than or equal to the lowest energy Eg. Combining the latter two observations allows the energy expectation value of to be used to produce a very important inequality ... [Pg.57]

Properties can be computed by finding the expectation value of the property operator with the natural orbitals weighted by the occupation number of each orbital. This is a much faster way to compute properties than trying to use the expectation value of a multiple-determinant wave function. Natural orbitals are not equivalent to HF or Kohn-Sham orbitals, although the same symmetry properties are present. [Pg.27]

A2.6540-g sample of an iron ore known to contain 53.51% w/w Fe is dissolved in a small portion of concentrated HCl and diluted to volume in a 250-mL volumetric flask. A spectrophotometric method is used to determine the concentration of Fe in this solution, yielding results of 5840, 5770, 5650, and 5660 ppm. Determine whether there is a significant difference between the experimental mean and the expected value at a = 0.05. [Pg.100]

When an analyst performs a single analysis on a sample, the difference between the experimentally determined value and the expected value is influenced by three sources of error random error, systematic errors inherent to the method, and systematic errors unique to the analyst. If enough replicate analyses are performed, a distribution of results can be plotted (Figure 14.16a). The width of this distribution is described by the standard deviation and can be used to determine the effect of random error on the analysis. The position of the distribution relative to the sample s true value, p, is determined both by systematic errors inherent to the method and those systematic errors unique to the analyst. For a single analyst there is no way to separate the total systematic error into its component parts. [Pg.687]


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See also in sourсe #XX -- [ Pg.195 ]




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