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Sufficient theory expression

The next section will focus on the representation necessary to express this sufficient theory to the computer, so that it can automatically carry out the reasoning associated with analyzing the examples selected by the syntactic criteria presented in this section. Section V will describe the learning methodology, which, using the representation of Section IV, will generate the new dominance and equivalence conditions. [Pg.302]

We need to introduce two more types of predicates to support the sufficient theory used in the analysis. As we have stated in Section III, D, the sufficient theory rests on being able to prove that the constraints on one state are looser than those on another. The predicate that is used to express this is looser - constraint — on — variable , which takes the form ... [Pg.312]

With the basic predicate types in place we can now define the various implications that will allow us to express the sufficient theory. There are two key steps that have to be made. The first is to take an intersituational variable and figure out what the constraint on the variable is, which of the... [Pg.312]

This completes the representation of the sufficient theory required for the flowshop example. It consists of about 10 different predicates listed in Table II and configured in four different implications (rules). These predicates have an intuitive appeal, and are not complex to evaluate, thus the sufficient theory could be thought of as being simple. The theory is capable of deriving the equivalence-dominance condition in flowshop problem. It is, however, expressed in terms that could be applied to any problem with that type of constraint. Thus it has generality, and since we can add new implications to deal with new constraint types, it has modularity. [Pg.314]

As the understanding of chemical bonding was advanced through such concepts as covalent and ionic bond, lone electron pairs etc., the theory of intermolecular forces also attempted to break down the interaction energy into a few simple and physically sensible concepts. To describe the nonrelativistic intermolecular interactions it is sufficient to express them in terms of the aforementioned four fundamental components electrostatic, induction, dispersion and exchange energies. [Pg.666]

Transverse pull-off tests induce mainly mode 1 loading, provided the base panel is sufficiently rigid. Finite element analyses have been performed to look at this geometry in more detail, and will be reported elsewhere, but here a simple analytical beam theory expression is used to predict the pull-off failure load [21] ... [Pg.289]

Several classification schemes based on the comparison of observed to limiting bandwidths have been proposed for weakly coupled systems. When q da 0.2 (i.e., for a system that is 60% localized ). Equation (11) combined with Equation (31) predicts very narrow absorption bands. For larger values of ctda > higher order perturbation theory expressions are necessary. Obviously, bandwidth criteria alone are not sufficient for distinguishing a valence localized Q da <0.5) from a delocalized (aoA = 0-5) system. [Pg.704]

The theory of molecular interactions can become extremely involved and the mathematical manipulations very unwieldy. To facilitate the discussion, certain simplifying assumptions will be made. These assumptions will be inexact and the expressions given for both dispersive and polar forces will not be precise. However, they will be reasonably accurate and sufficiently so, to reveal those variables that control the different types of interaction. At a first approximation, the interaction energy, (Ud), involved with dispersive forces has been calculated to be... [Pg.64]

As the metallic particles are assumed to be sufficiently large for macroscopic dielectric theory to be applicable, we can substitute for a the expression for the polarisability of metallic particle immersed in an insulator. The dipole moment is given by the integration of the polarisation over the volume V. Thus, if the polarisation is uniform ... [Pg.96]

The presenoe of the 8-function indicates that the factor (E + ie) l in the limit as e - 0 only has a meaning in the sense of distribution theory, i.e., when multiplied by a sufficiently smooth function f(E) whose support is closed and bounded, and then integrated over the range of the possible values of E. Consider, therefore, the limit f -> oo of the expression... [Pg.601]

In the Taylor-Prandtl modification of the theory of heat transfer to a turbulent fluid, it was assumed that the heat passed directly from the turbulent fluid to the laminar sublayer and the existence of the buffer layer was neglected. It was therefore possible to apply the simple theory for the boundary layer in order to calculate the heat transfer. In most cases, the results so obtained are sufficiently accurate, but errors become significant when the relations are used to calculate heat transfer to liquids of high viscosities. A more accurate expression can be obtained if the temperature difference across the buffer layer is taken into account. The exact conditions in the buffer layer are difficult to define and any mathematical treatment of the problem involves a number of assumptions. However, the conditions close to the surface over which fluid is flowing can be calculated approximately using the universal velocity profile,(10)... [Pg.727]

A pure gas is absorbed into a liquid with which it reacts. The concentration in the liquid is sufficiently low for the mass transfer to be governed by Pick s law and the reaction is first order with respect to the solute gas. It may be assumed that the film theory may be applied to the liquid and that the concentration of solute gas falls from the saturation value to zero across the film. Obtain an expression for the mass transfer rate across the gas-liquid interface in terms of the molecular diffusivity, 1), the first order reaction rate constant k. the film thickness L and the concentration Cas of solute in a saturated solution. The reaction is initially carried our at 293 K. By what factor will the mass transfer rate across the interface change, if the temperature is raised to 313 K7... [Pg.856]

State the assumptions made in the penetration theory for the absorption of a pure gas inlo a liquid. The surface of an initially solute-free liquid is suddenly exposed to a soluble gas and the liquid is sufficiently deep for no solute to have time to reach the bottom of the liquid. Starting with Hick s second law ol diffusion obtain an expression for (i) the concentration, and (ii) the muss transfer rate at a time t and a depth v below the surface. [Pg.860]

For ionic compounds, crystal field theory is generally regarded a sufficiently good model for qualitative estimates. Covalency is neglected in this approach, only metal d-orbitals are considered which can be populated with zero, one or two electrons. To evaluate (Vzz)vai 4t the Mdssbauer nucleus, one may simply take the expectation value of the expression — e(3cos 0 — for every electron in a valence orbital i/, of the Mdssbauer atom and sum up,... [Pg.98]

Although applications of perturbation theory vary widely, the main idea remains the same. One starts with an initial problem, called the unperturbed or reference problem. It is often required that this problem be sufficiently simple to be solved exactly. Then, the problem of interest, called the target problem, is represented in terms of a perturbation to the reference problem. The effect of the perturbation is expressed as an expansion in a series with respect to a small quantity, called the perturbation parameter. It is expected that the series converges quickly, and, therefore, can be truncated after the first few terms. It is further expected that these terms are markedly easier to evaluate than the exact solution. [Pg.33]

In general, no simple, consistent set of analytical expressions for the resonance condition of all intradoublet transitions and all possible rhombicities can be derived with the perturbation theory for these systems. Therefore, the rather different approach is taken to numerically compute all effective g-values using quantum mechanics and matrix diagonalization techniques (Chapters 7-9) and to tabulate the results in the form of graphs of geff,s versus the rhombicity r = E/D. This is a useful approach because it turns out that if the zero-field interaction is sufficiently dominant over... [Pg.84]


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Expression theory

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