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Iterative migration

The weighted regularized gradient direction on the n-th iteration can be calculated by a formula, derived from (11.33) by analogy with the formula (5.142)  [Pg.343]

Ey = Ey ( t ) is the field calculated by forward modeling for the geoelectrical model with the conductivity distribution (t (x, z), and is the migrated residual field [Pg.344]

computed as the difference between the theoretical predicted field Ey, found on the nth iteration, and the observed field  [Pg.344]

The optimal length of the step k can be determined by a formula similar to (11.47)  [Pg.344]

The migration apparent resistivity, introduced above, appears as the first iteration in this iterative process. [Pg.344]


In the general case of an iterative inversion scheme (15.135), we should apply the adjoint Kirchhoff operator K to the residual field Rn = K(A ) — da computed on each iteration. Each of these applications is equivalent to the standard migration of the residual field. Thus, iterative Kirchhoff inversion can be treated as an iterative migration algorithm,... [Pg.494]

Thus, the corrections to the velocities Cpb (r) and Csb (r) on the first iteration can be obtained by correlating the back-propagated scattered elastic field with the derivatives of the incident field U (r,t). This transformation is similar to wavefield migration described previously. Thus we see that elastic field inversion can be constructed by iterative migration of the residual elastic data. [Pg.526]

Master equation methods are not tire only option for calculating tire kinetics of energy transfer and analytic approaches in general have certain drawbacks in not reflecting, for example, certain statistical aspects of coupled systems. Alternative approaches to tire calculation of energy migration dynamics in molecular ensembles are Monte Carlo calculations [18,19 and 20] and probability matrix iteration [21, 22], amongst otliers. [Pg.3021]

These studies vary the relative aggregation of the solute encoded in the Tb and J values for (SS). Select several sets of these parameters using the setup in Example 4.4, run the dynamics for 1000 iterations, and record the average distance the S molecules have migrated from the center of the grid. [Pg.65]

A generic problem with profile methods that iterate is the possibility of profile wander (also called matrix migration). This occurs when sequences found in early rounds of the iterative search are not found in later rounds of the search. This problem affects both PSI-BLAST and HMMER. This means that one should record all the intermediate steps so that these lost members of the family can be recovered. Profile wander only becomes a problem for large protein families, and therefore the cause of the profile wander may be related to the limits of modeling using profiles. [Pg.155]

To obtain a true k in MEEKC, it is important to trace the migration of the pseudostationary phase accurately. Sudan III, timepidium bromide, and quine, which have generally been used as tracers for micelles in MEKC, could not be employed as tracers for microemulsions consisting of sodium dodecylsulfate salt (SDS) or cetyltrimethylammonium bromide (CTAB), n-butanol and heptane (12). An iteration method based on a linear relationship between log k and the carbon number for alkylbenzenes (13) seems to provide a reasonable value of the migration time of the microemulsions. Dodecylbenzene shows a migration time larger than the value calculated by the iteration method and those of other hydrophobic compounds, such as phenanthrene, fluoranthrene, and Sudan III (Table 1). Methanol and ethanol were used as tracers for the aqueous phase. [Pg.144]

The foundation for systematic project planning is the conceptual site model (CSM). Under Triad, a CSM is developed for each site, based on all available historical and current information to estimate where contamination might be located how much is there and how it varies across the site possible fate and migration of the contamination exposure risks associated with the site and contaminants and means of mitigating exposure risk. Once the project team develops an initial CSM, it identifies data gaps and seeks additional information to resolve those gaps. Throughout the project, the team updates the CSM to reflect new data and identify additional needs for data collection. This iterative process continues until the site project team is confident in its decisions about actions that need to be taken to address the site contamination. [Pg.338]

The most severe problem with graphite is that the transport of eroded material is very complex and the migration of which over long distances to remote areas may lead to the build-up of thick carbon layers which can trap rather large amounts of tritium (see Sect. 1.4.1). Ongoing R D is concentrating on an optimized detailed design of the first ITER divertor where the build-up of thick deposition layers is minimized, the formation of layers on... [Pg.8]

The chemistry of diene iron tricarbonyl complexes described above has been in a number of total syntheses. An iterative stereospecific 1,3-migration of the iron tricarbonyl moiety was used to prepare compounds with multiple chiral centers. An example of one iteration can be seen in Scheme 168. Ester hydrolysis of (105) and protection of the resulting alcohol gives (106). Reduction of the nitrile with DIBAL-H followed by olefination furnished (107). Treatment of (107) with a base resulted in the migration of iron toward the nitrile to give (108). The uncomplexed double bond can... [Pg.3255]

Using gravity migration, we can find the first iteration for the density of the gravity... [Pg.184]

Note that we can give the same physical interpretation to every subsequent iteration in the iterative scheme (7.26). According to formulae (7.12) and (7.43), the direction of the steepest ascent I (p ) on each iteration can be computed using migration of the residual field (Q — gr (C)], which is the difference between the predicted field on the n-th iteration, g , and the observed gravity field gr ... [Pg.186]

Thus, as in the gravity case, the calculation of the each iteration in the conjugate gradient method for magnetic potential inversion can be based on the migration transformation. [Pg.190]

As the overall aim of parameter determination is the (simulation-based) prediction of the process behavior the final decision about the suitability of the isotherm equation can only be made by comparing experimental and theoretical elution profiles (Section 6.6). Depending on the desired accuracy, this may involve iteration loops for the selection of isotherm equations or in some cases even the methods (Fig. 6.16). In this context it should be remembered that, according to the model equations (e.g. Eq. 6.47), the migration velocity and thus the position of the profiles is a function of the isotherm slope. Therefore, it is most important for the reliability of process simulation that the slopes of the measured and calculated elution profile fit to each other. If the deviations are unacceptable, another isotherm equation should be tested. [Pg.290]

Values of Yq are often taken to be the surface tension of the pure components, Y and have also been obtained by iterative procedures. Figure 4a shows a typical plot of Y as a function of x for a binary slag and the individual x Yi contributions have also been included. These methods work well for certain slag mixtures but break down when surface-active constituents, such as P205 are present. These components migrate preferentially to the surface and cause a sharp decrease in the surface tension and consequently only very small concentrations are required to cause an appreciable decrease in Y. Thus some unreported or undetected impurity could have a marked effect on the surface tension of the slag and thereby produce an apparent error in the value estimated by the model. In this respect surface tension differs from all the other physical properties which are essentially bulk properties. [Pg.202]

Next, all sub-systems should be integrated and incrementally optimized. The migration based technologies would be valuable because design iteration to an earlier stage would be costly in terms of design cost and turn-around time. Finally, the chip level routing could complete all necessary connections and make the system ready for final tape-out. [Pg.186]


See other pages where Iterative migration is mentioned: [Pg.187]    [Pg.188]    [Pg.343]    [Pg.344]    [Pg.357]    [Pg.358]    [Pg.359]    [Pg.518]    [Pg.632]    [Pg.187]    [Pg.188]    [Pg.343]    [Pg.344]    [Pg.357]    [Pg.358]    [Pg.359]    [Pg.518]    [Pg.632]    [Pg.73]    [Pg.869]    [Pg.51]    [Pg.34]    [Pg.619]    [Pg.18]    [Pg.362]    [Pg.112]    [Pg.2067]    [Pg.3376]    [Pg.186]    [Pg.190]    [Pg.190]    [Pg.331]    [Pg.343]    [Pg.345]    [Pg.357]    [Pg.503]    [Pg.503]    [Pg.793]    [Pg.112]    [Pg.187]   


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ITER

Iterated

Iteration

Iteration iterator

Iterative

Iterative gravity migration

Iterative migration in the time domain

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