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Current boundary

They performed an extensive case study to demonstrate the use of automatic history matching to reservoir characterization. For example, if the estimated permeability of a particular zone is unrealistically small compared to geological information, there is a good chance that an impermeable barrier is present. Similarly if the estimated porosity of a zone approaches unrealistically high values, chances are the zone of the reservoir should be expanded beyond its current boundary. [Pg.384]

To maximize (1/e) becomes a modem need that invites conscious effort from all of us who write, issue, or edit papers, reports, reviews, etc. We believe it to be a major goal for a publication such as ours to integrate information effectively and with mature criticality to present that which orients and instructs concerning the state of the current boundary of knowledge, and which thereby may significantly influence the propagative chain process of evolving our science. [Pg.416]

At the same time, examples where the GB model breaks down are also well known. Part of the overall error in these cases is attributable to the PB GB approximation, while the remainder comes from the more fundamental limitations of the general implicit solvent framework itself. These examples are extremely important for defining the current boundaries of applicability of the GB model they also suggest directions for future improvements. [Pg.134]

In Figure 7.21(b), the PFR trajectory, and the shape of candidate region, is shown for an additional PFR. The point at which the base trajectory touches the current boundary is now given by point G. In order to achieve point G, two PFRs in series are required with interstage bypass of feed to the exit of each reactor. The PFR trajectory GHD achieves a lower overall residence time than before. Again, the inclusion of an additional PFR increases the complexity of the structure however, a lower system residence time is obtained. [Pg.209]

The system considered is composed of two 5-gal cans containing UO2 of various densities, 5 wt% enriched in the U Isotope, and with a hydrogen-to-uranium ratio of 0 45. The cans are contain In a 16-gal drum which is in turn centered and supported within a 55-gal drUpi Iv insulating material in which the hydrogien content was allowed to vary for. calculatlonal inirposes. The zero-current boundary conditions are implied at file surface of the outer drum that is, assuitaing an infinite array of such containers. [Pg.361]

The critical current density [Eqs. (23.15) and (23.16)] indicates the left (low-current) boundary of the transition region (/o/jcrit = ) For the estimate, we may neglect the finite width of the transition region and assume thatj crit separates the low- and high-current regimes of CL operation. [Pg.652]

After a brief review of the fundamentals, the current boundaries of the technique as they apply to particle sizing will be illustrated with examples. The paper concludes with a brief discussion of new developments in PCS instrumentation. [Pg.174]

At sufficiently high frequency, the electromagnetic skin depth is several times smaller than a typical defect and induced currents flow in a thin skin at the conductor surface and the crack faces. It is profitable to develop a theoretical model dedicated to this regime. Making certain assumptions, a boundary value problem can be defined and solved relatively simply leading to rapid numerical calculation of eddy-current probe impedance changes due to a variety of surface cracks. [Pg.141]

Due to its importance the impulse-pulse response function could be named. .contrast function". A similar function called Green s function is well known from the linear boundary value problems. The signal theory, applied for LLI-systems, gives a strong possibility for the comparison of different magnet field sensor systems and for solutions of inverse 2D- and 3D-eddy-current problems. [Pg.372]

Figure A2.4.12 shows the two possibilities that can exist, m which the Galvani potential of the solution, (jig, lies between ( )(I) and ( )(n) and in which it lies below (or, equivalently, above) the Galvani potentials of the metals. It should be emphasized that figure A2.4.12 is highly schematic in reality the potential near the phase boundary in the solution changes initially linearly and then exponentially with distance away from the electrode surface, as we saw above. The other point is that we have assumed that (jig is a constant in the region between the two electrodes. This will only be true provided the two electrodes are iimnersed in the same solution and that no current is passing. Figure A2.4.12 shows the two possibilities that can exist, m which the Galvani potential of the solution, (jig, lies between ( )(I) and ( )(n) and in which it lies below (or, equivalently, above) the Galvani potentials of the metals. It should be emphasized that figure A2.4.12 is highly schematic in reality the potential near the phase boundary in the solution changes initially linearly and then exponentially with distance away from the electrode surface, as we saw above. The other point is that we have assumed that (jig is a constant in the region between the two electrodes. This will only be true provided the two electrodes are iimnersed in the same solution and that no current is passing.
At low currents, the rate of change of die electrode potential with current is associated with the limiting rate of electron transfer across the phase boundary between the electronically conducting electrode and the ionically conducting solution, and is temied the electron transfer overpotential. The electron transfer rate at a given overpotential has been found to depend on the nature of the species participating in the reaction, and the properties of the electrolyte and the electrode itself (such as, for example, the chemical nature of the metal). [Pg.603]

Equation (A3.3.73) is referred to as the Gibbs-Thomson boundary condition, equation (A3.3.74) detemiines p on the interfaces in temis of the curvature, and between the interfaces p satisfies Laplace s equation, equation (A3.3.71). Now, since ] = -Vp, an mterface moves due to the imbalance between the current flowing into and out of it. The interface velocity is therefore given by... [Pg.748]

From polarization curves the protectiveness of a passive film in a certain environment can be estimated from the passive current density in figure C2.8.4 which reflects the layer s resistance to ion transport tlirough the film, and chemical dissolution of the film. It is clear that a variety of factors can influence ion transport tlirough the film, such as the film s chemical composition, stmcture, number of grain boundaries and the extent of flaws and pores. The protectiveness and stability of passive films has, for instance, been based on percolation arguments [67, 681, stmctural arguments [69], ion/defect mobility [56, 57] and charge distribution [70, 71]. [Pg.2725]


See other pages where Current boundary is mentioned: [Pg.278]    [Pg.501]    [Pg.916]    [Pg.173]    [Pg.243]    [Pg.82]    [Pg.209]    [Pg.218]    [Pg.269]    [Pg.269]    [Pg.155]    [Pg.747]    [Pg.205]    [Pg.14]    [Pg.187]    [Pg.245]    [Pg.262]    [Pg.278]    [Pg.501]    [Pg.916]    [Pg.173]    [Pg.243]    [Pg.82]    [Pg.209]    [Pg.218]    [Pg.269]    [Pg.269]    [Pg.155]    [Pg.747]    [Pg.205]    [Pg.14]    [Pg.187]    [Pg.245]    [Pg.262]    [Pg.600]    [Pg.671]    [Pg.1924]    [Pg.1929]    [Pg.1940]    [Pg.349]    [Pg.17]    [Pg.106]    [Pg.345]    [Pg.260]    [Pg.190]    [Pg.203]    [Pg.126]    [Pg.377]    [Pg.417]    [Pg.418]    [Pg.431]    [Pg.340]    [Pg.236]    [Pg.66]   
See also in sourсe #XX -- [ Pg.3 , Pg.8 , Pg.85 ]




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