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Singularity correction

The correction terms can be computed using either Yx or Xa. However, it is clear that the correction terms will depend on which choice is used since the moments controlled by DQMOM are different (i.e., (Y ) vs. (X(")). Thus, for example, with fixed N one set of moments may lead to singular correction terms, but not the other. In general, we can continue to solve for the mass fractions in the CFD model, but with the correction terms computed using the cumulative mass fractions as follows. [Pg.271]

Bieniasz LK (2005) A singularity correction procedure for digital simulation of potential-step chronoamperometric transients in one-dimensional homogeneous reaction-diffusion systems. Electrochim Acta 50 3253-3261... [Pg.174]

The solution of the transport (continuity) equation differs from Equation (6.185) by the singular correction term w(q), which is to be found from the equation... [Pg.105]

For both first-order and continuous phase transitions, finite size shifts the transition and rounds it in some way. The shift for first-order transitions arises, crudely, because the chemical potential, like most other properties, has a finite-size correction p(A)-p(oo) C (l/A). An approximate expression for this was derived by Siepmann et al [134]. Therefore, the line of intersection of two chemical potential surfaces Pj(T,P) and pjj T,P) will shift, in general, by an amount 0 IN). The rounding is expected because the partition fiinction only has singularities (and hence produces discontinuous or divergent properties) in tlie limit i—>oo otherwise, it is analytic, so for finite Vthe discontinuities must be smoothed out in some way. The shift for continuous transitions arises because the transition happens when L for the finite system, but when i oo m the infinite system. The rounding happens for the same reason as it does for first-order phase transitions whatever the nature of the divergence in thennodynamic properties (described, typically, by critical exponents) it will be limited by the finite size of the system. [Pg.2266]

Elements of the matrix —are usually small in the vicinity of a conical intersection and can be added to to give a corrected diabatic energy matrix. As can be seen, whereas in Eq. (15) contains both the singular... [Pg.197]

The problem is, however, the evaluation (36) may create a considerable error due to the singularity of the kernel function. In these cases, a correction process has to be applied. Here a two-level grid system with H=2h is used as an example to illustrate the approach of correction. [Pg.123]

Langer correction is required by the presence of the r singularity, arising from removal of the first derivative term in Eq. (27), even for k = 0. [Pg.55]

As noted earlier, the sum of the mass fractions is unity and thus Eq. (86) will be consistent with Eq. (85) only if the sum of the correction term b m over all chemical species a = 1,..., K is null. In general, this will not be the case if Eq. (89) is used. Another difficulty that can arise is that the mass fractions in two environments may be equal, e.g., i = a2, and thus the coefficient matrix in Eq. (89) will be singular. This can occur, for example, in the equilibrium-chemistry limit where the compositions depend only on the mixture fraction, i.e., (j) — co(0- F°r chemical species that are not present in the feed streams, the equilibrium values for = 0 and = 1 are zero, but for intermediate values of the mixture fraction, the equilibrium values are positive. This implies that the equilibrium values will be the same for at least two values of the mixture fraction in the range 0< < 1. Thus, in the equilibrium limit it is inevitable that two environments will have equal mass fractions for certain species at some point in the flow field. Since singularity implies an underlying correlation between... [Pg.270]

In most cases, the structural procedure is able to determine whether the measurements can be corrected and whether they enable the computation of all of the state variables of the process. In some configurations this technique, used alone, fails in the detection of indeterminable variables. This situation arises when the Jacobian matrix used for the resolution is singular. [Pg.53]

Asymptotic Laws and Preasymptotic Correction Formulas for the Relaxation Near Glass-Transition Singularities. [Pg.61]

To achieve subject-verb agreement, brst determine whether your subject is singular or plural, and then pair it with the correct verb form. [Pg.111]

Correct One of my friends is going to school. (Singular subject takes singular verb.)... [Pg.111]

Agreement may be difficult to determine when the noun follows the verb. Common examples include sentences that begin with there is and there are, and here is and here are. When editing your work, remember to brst determine whether your subject is singular or plural, and then match it to the correct verb. [Pg.111]

For the computation of the pseudo-inverse, it is crucial that the vectors f j are not parallel, or more correctly, that they are linearly independent. Otherwise, the matrix FlF is singular and cannot be inverted. Matlab issues a warning. We can gain a certain level of understanding by adapting Figure 4-10 ... [Pg.119]

Real data are never noise-free and in purely mathematical terms, the rank of a noisy data matrix is always the smaller of the number of rows or columns. So, the question obviously is, where do we stop What is the correct number of independent species or the correct rank of the matrix Y How many singular values are statistically relevant Most importantly for the chemist what is the practical or the chemical rank how many components are there in the system ... [Pg.218]

Until you become more familiar with data being plural, you may read over a passage using data with a singular verb and not even notice the error (e.g., data shows sounds correct to many native English speakers). It is difficult to catch a mistake that does not sound wrong. In fact, many chemists use the word data as... [Pg.154]

The following sentences may contain one or two errors with regard to singular and plural forms of words. Decide whether each sentence contains errors. If it does, correct the sentence. If the sentence is correct as written, indicate no change needed . [Pg.156]

From this equation one finds that has a Coulombic singularity near the atomic nucleus. Furthermore it follows that if the GGA reproduces the correct asymptotic behavior of the Slater potential... [Pg.154]


See other pages where Singularity correction is mentioned: [Pg.80]    [Pg.80]    [Pg.159]    [Pg.80]    [Pg.80]    [Pg.159]    [Pg.204]    [Pg.235]    [Pg.400]    [Pg.179]    [Pg.179]    [Pg.84]    [Pg.129]    [Pg.259]    [Pg.818]    [Pg.56]    [Pg.105]    [Pg.6]    [Pg.233]    [Pg.303]    [Pg.202]    [Pg.308]    [Pg.339]    [Pg.506]    [Pg.611]    [Pg.271]    [Pg.258]    [Pg.131]    [Pg.63]    [Pg.141]    [Pg.71]    [Pg.155]    [Pg.109]   
See also in sourсe #XX -- [ Pg.159 ]




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