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Optimal choice of

The optimal choice of the time scaling factor p described by Clowes (1965) is generalized here for any L2 stable system. [Pg.19]

Theorem 2.1 Given that the Laguerre coefficients cj can be obtained from Equations (2.14), and assuming that the true system G s) is L2 stable, then the derivative of the loss function V with respect to the time scaling factor p is given by [Pg.20]

To prove the theorem, we first require the following lemma. [Pg.20]

Lemma 2.1 For some p 0, the Laplace transforms of the Laguerre functions given in Equations (2.10) satisfy the following equality [Pg.20]

Proof of Theorem 2.1 Note that from Equations (2.14) [Pg.21]


To verify the modelling of the data eolleetion process, calculations of SAT 4, in the entrance window of the XRII was compared to measurements of RNR p oj in stored data as function of tube potential. The images object was a steel cylinder 5-mm) with a glass rod 1-mm) as defect. X-ray spectra were filtered with 0.6-mm copper. Tube current and exposure time were varied so that the signal beside the object. So, was kept constant for all tube potentials. Figure 8 shows measured and simulated SNR oproj, where both point out 100 kV as the tube potential that gives a maximum. Due to overestimation of the noise in calculations the maximum in the simulated values are normalised to the maximum in the measured values. Once the model was verified it was used to calculate optimal choice of filter materials and tube potentials, see figure 9. [Pg.212]

Since chemical reactions usually show significant nonadiabaticity, there are naturally quantitative errors in the predictions of the vibrationally adiabatic model. Furthermore, there are ambiguities about how to apply the theory such as the optimal choice of coordinate system. Nevertheless, this simple picture seems to capture the essence of the resonance trapping mechanism for many systems. We also point out that the recent work of Truhlar and co-workers24,34 has demonstrated that the reaction dynamics is largely controlled by the quantized bottleneck states at the barrier maxima in a much more quantitative manner than expected. [Pg.49]

However, this analysis has been performed from a purely statistical perspective, leading to the minimal statistical error for the calculation. The phase space relationship, the staging scheme (conceptual intermediate M), and thus the accuracy of the calculation are not included in Bennett s picture. However, it turns out that the calculation is also optimal from the accuracy point of view. With this optimal choice of C = AA, the weight function w(Au) given by (6.64) has its peak exactly at the crossover between / and g, where AU = AA [cf. (6.15)]. In contrast, the weights for the low-Z w tail of / and high-Zll tail of g are diminished, thus resulting in small systematic error. [Pg.231]

SM-4) A method for finding the optimal choice of mode over one or more epochs, based on the measure of effectiveness. [Pg.276]

Vaclavek, V. (1969). Studies on system engineering. III. Optimal choice of the balance measurements in complicated chemical engineering systems. Chem. Eng. Sci. 24,947-955. [Pg.27]

FIGURE 5.27 SVMs applied to the glass data with six glass types. The optimal choice of the parameter y is 0.1, leading to a test error of 0.34. [Pg.253]

In one study, various distinct types of polar modifiers to n-hexane were tested for 3-chloro-l-phenylpropanol (3CPP) and 1-phenylpropanol (IPP) enantiomer separation [53]. Thereby, alcohol modifiers turned out to be more effective displacers of the solutes from the adsorption places on the sorbent surface, yet aprotic polar modifiers provided higher separation factors (with ethyl acetate in n-hexane affording the best separations for these chiral alcohols). It is evident, though, that the optimal choice of polar modifier is strongly solute dependent and can therefore not be generalized. [Pg.17]

We now consider the uncertainty in Ti determined by this procedure. The first cause of inaccuracy may be an inappropriate choice of r, with respect to the expected T values. It can be shown that the optimal choice of r is 1.3 Ti, whereas the relative uncertainty ATi/Ti does not exceed twice the... [Pg.320]

In fact, SRPA is the first TDLDA iteration with the initial wave function (7). A single iteration is generally not enough to get the complete convergence of TDLDA results. However, SRPA calculations demonstrate that high accuracy can be achieved even in this case if to ensure the optimal choice of the input operators Qk and Pk and keep sufficient amount of the separable terms (see discussion in Sec. 5). In this case, the first iteration already gives quite accurate results. [Pg.137]

The laser used to generate the pump and probe pulses must have appropriate characteristics in both the time and the frequency domains as well as suitable pulse power and repetition rates. The time and frequency domains are related through the Fourier transform relationship that hmits the shortness of the laser pulse time duration and the spectral resolution in reciprocal centimeters. The limitation has its basis in the Heisenberg uncertainty principle. The shorter pulse that has better time resolution has a broader band of wavelengths associated with it, and therefore a poorer spectral resolution. For a 1-ps, sech -shaped pulse, the minimum spectral width is 10.5 cm. The pulse width cannot be <10 ps for a spectral resolution of 1 cm . An optimal choice of time duration and spectral bandwidth are 3.2 ps and 3.5 cm. The pump pulse typically is in the UV region. The probe pulse may also be in the UV region if the signal/noise enhancements of resonance Raman... [Pg.881]

There are a variety of FPA detectors available that are sensitive in the NIR spectral region. The optimal choice of detectors depends on several factors desired wavelength range, whether the application will be laboratory based or part of a process environment, the sensitivity needed to adequately differentiate sample spectra and price. The figure of merit most often used to describe detector performance is specific detectivity or D, which is the inverse of noise equivalent power (NEP), normalized for detector area and unit bandwidth. NEP is defined as the radiant power that produces a signal-to-dark-current noise ratio of unity. [Pg.28]

The optimal choice of the dividing surface S(pj,r) is, according to the Wigner theorem, the surface that gives the smallest rate constant k(T). In principle, it can be determined by a variational calculation of k(T) with respect to the surface such that 6k(T) = 0. [Pg.119]

If a trajectory makes it to the product side, as sketched in Fig. 5.1.2, then it is also propagated backwards in time from the initial position to check if it originated on the reactant side. If so, the trajectory is marked as successful. In all other cases, that is, the trajectories do not make it to the product side, or if so, do not originate on the reactant side, then they are registered as unsuccessful. The fraction k of the total number of trajectories that are marked successful is now used to rectify the rate constant for not being calculated with the optimal choice of the dividing surface, and the final result is reported as... [Pg.125]

Table 12. Examples of optimized choice of explosives for canine training... [Pg.427]


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