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Ignorance representations

Ignoring all nonadiabatic couplings to higher electronic states, the nuclear motion in a two-state elechonic manifold is described explicitly in the adiabatic representation by... [Pg.610]

Fig. 4. Schematic representation of a two-dimensional model to account for the shear modulus of a foam. The foam stmcture is modeled as a coUection of thin films the Plateau borders and any other fluid between the bubbles is ignored. Furthermore, aH the bubbles are taken to be uniform in size and shape. Fig. 4. Schematic representation of a two-dimensional model to account for the shear modulus of a foam. The foam stmcture is modeled as a coUection of thin films the Plateau borders and any other fluid between the bubbles is ignored. Furthermore, aH the bubbles are taken to be uniform in size and shape.
This basic difference equation - known as the Schema Theorem [holl92] - expresses the fact that the sample representation of schemas whose average fitness remains above average relative to the whole population increases exponentially over time. As it stands, however, this equation addresses only the reproduction operator, and ignores effects of both crossover and mutation. [Pg.591]

Point defects in solids make it possible for ions to move through the structure. Ionic conductivity represents ion transport under the influence of an external electric field. The movement of ions through a lattice can be explained by two possible mechanisms. Figure 25.3 shows their schematic representation. The first, called the vacancy mechanism, represents an ion that hops or jumps from its normal position on the lattice to a neighboring equivalent but vacant site or the movement of a vacancy in the opposite direction. The second one is an interstitial mechanism where an interstitial ion jumps or hops to an adjacent equivalent site. These simple pictures of movement in an ionic lattice, known as the hopping model, ignore more complicated cooperative motions. [Pg.426]

Ignoring the quite distinct functions and hydrodynamic conditions which exist in the actual mixer and settler items of the combined mixer-settler unit, it is possible, in principle, to treat the combined unit simply as a well-mixed equilibrium stage. This is done in exactly the way, as considered previously in Secs. 3.2.1 to 3.2.6. A schematic representation of an actual mixer-settler... [Pg.183]

The most serious problem with input analysis methods such as PCA that are designed for dimension reduction is the fact that they focus only on pattern representation rather than on discrimination. Good generalization from a pattern recognition standpoint requires the ability to identify characteristics that both define and discriminate between pattern classes. Methods that do one or the other are insufficient. Consequently, methods such as PLS that simultaneously attempt to reduce the input and output dimensionality while finding the best input-output model may perform better than methods such as PCA that ignore the input-output relationship, or OLS that does not emphasize input dimensionality reduction. [Pg.52]

A number of the assumptions used in the BET theory have been questioned for real samples [6]. One assumption states that all adsorption sites are energetically equivalent, which is not the case for normal samples. The BET model ignores lateral adsorbate interactions on the surface, and it also assumes that the heat of adsorption for the second layer and above is equal to the heat of liquefaction. This assumption is not valid at high pressures and is the reason for using adsorbate pressures less than 0.35. In spite of these concerns, the BET method has proven to be an accurate representation of surface area for the majority of samples [9,10]. [Pg.259]

One really may need an inherently transient LES to capture all these details. The finer the grid for such a LES, the more reliably the local transient conditions may be taken into account in reproducing this turbulent mass transfer process (while ignoring the issue of supplying the heat for the dissolution which may also depend on a proper representation of the turbulent-flow field). An additional important issue is how many particles have to be tracked for a proper representation of the transient spatial distribution of the particles over the vessel. [Pg.197]

The thermodynamic stability of a complex ML formed from an acceptor metal ion M and ligand groups L may be approached in two different but related ways. (The difference between the two approaches lies in the way in which the formation reaction is presented.) Consistent with preceding sections, an equilibrium constant may be written for the formation reaction. This is the formation constant Kv In a simple approach, the effects of the solvent and ionic charges may be ignored. A stepwise representation of the reaction enables a series of stepwise formation constants to be written (Table 3.5). [Pg.43]

Our discussion of electronic structure has been in terms of band filling only. Of course, there is a lot more to know about band structures. The density of states represents only a highly simplified representation of the actual electronic structure, which ignores the three-dimensional structure of electron states in the crystal lattice. Angle-dependent photoemission gives information on this property of the electrons. The interested reader is referred to standard books on solid state physics [9,10] and photoemission [16,17]. The interpretation of photoemission and X-ray absorption spectra of catalysis-oriented questions, however, is usually done in terms of the electron density of states only. [Pg.304]

For induction from <3 7 to (3 7, we must distinguish between the indices g or u of the inducing representation and consequently ignore induced diagram pairs with an odd (for g) or even (for w) number of boxes in the minus component. Thus, referring to Fig. 4, if the inducing representation of S7 is (3,2 2) , we obtain only the representations under column (w) in the figure if it is (3,22)ff we get only those in column (g). [Pg.35]

Values based on Eq. (39) are given in Fig. 6 in terms of S ps and in Fig. 7 in terms of equivalent charge-to-mass ratio for various values of surface tension. Actually the maximum value of Sps before breakup, as given by Eq. (39), is independent of pressure. The pressure term has been incorporated in Figs. 6 and 7 in order to permit direct comparison with later developments of instability due to corona. For present purposes, Figs. 6 and 7 will give a correct representation of Eq. (39) if all pressure terms (in the coordinates or in the parameter) are ignored or assumed to be unity. [Pg.25]

Cui et al. performed similar analyses to fhose of Dupuis and co-workers. The side chain-side chain radial disfribufion functions (RDFs) reported by Cui et al. show remarkable qualitative deviation from fhose in Zhou et al. i It is of note that the united atom approach used by Cui and co-workers ignored electrostatic interactions between CP2 groups of the polymeric backbone. This can lead to a poor description of fhe hydrated structure in the regions close to the polymeric backbones, unlike the all-atom force field used in Zhou et al. ° For the sake of limited computational resources, Cui et al. used a relatively short representation of Nation ionomer chains consisting of three monomers as compared to the ten monomers used by Vishnyakov and Neimark or Urata et al. It can be expected that structural correlations will strongly depend on this choice. [Pg.361]

The chemist s sketch, processed into the list representation just described, is not yet very valuable the system at the moment is very ignorant of the structure of the molecule in question. But the chemist knows much of the molecule from little more than the diagram. How does the chemist "see" a complex molecular diagram ... [Pg.164]

On the other hand, occasional irregular deviations from ideality can be ignored in constructing graphical representations for double-strand polymers and in assigning corresponding names. [Pg.320]

In order to solve Eqs. (135) and (136), one may follow the method reported in Refs. [24, 25]. Thus each of these equations has two solutions but one of the solutions can be ignored, since it does not correspond to an ensemble A -representable 1-RDM. [Pg.236]


See other pages where Ignorance representations is mentioned: [Pg.66]    [Pg.1185]    [Pg.2644]    [Pg.18]    [Pg.264]    [Pg.209]    [Pg.92]    [Pg.164]    [Pg.47]    [Pg.662]    [Pg.75]    [Pg.153]    [Pg.190]    [Pg.15]    [Pg.140]    [Pg.12]    [Pg.246]    [Pg.163]    [Pg.286]    [Pg.122]    [Pg.369]    [Pg.44]    [Pg.89]    [Pg.456]    [Pg.219]    [Pg.165]    [Pg.123]    [Pg.241]    [Pg.380]    [Pg.228]    [Pg.255]    [Pg.172]    [Pg.48]   
See also in sourсe #XX -- [ Pg.48 ]




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Ignorance

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