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Functions spacing considerations

What does all this mean in a practical way Certainly we have no intention of writing programs for all partially computable functions indeed time and space considerations do not allow execution of all partially computable functions. The functions actually computed form a very small subset of the primitive recursive functions. We do not know, however, whether they fall into a class for which partial correctness is partially decidable one suspects not. In any case, since we obtain our undecidability results for programs with very simple structure, there can be nothing in the structure of "real" programs which will allow us by and of itself to conclude that the properties of interest are at least partially decidable. [Pg.212]

A third and more complex way is to first find another set of operators 0M, which have certain fundamental properties and are homomorphic with the symmetry operations, and then find a set of matrices which are homomorphic with these new operators. This last step is achieved by consideration of the effect that the 0M have on some family of mathematical functions (a so-called function space) e.g. a set of five d-orbitals it will be seen that the choice of the function space and the choice of the 0M are bound up with each other. It is important to realize that this method involves two steps as opposed to the first two methods which involve only one. [Pg.72]

The results can be divided into studies of the coke deposition rate as a function of the amount and type of reactants injected, and studies of the activity (cumene conversion) vs. the cumulative coke level Because of space considerations, only the former is discussed. [Pg.275]

Kittel s simple theory gives rise to the prediction of purely repulsive interaction curves. This is in marked contrast to the defect force theories which predict the existence of minima in the interaction function. Kittel argues that repulsive curves are required to explain infinite adaptability. For if minima were present in the interaction function, those solutions whose compositions corresponded to interplanar spacings considerably displaced from the minimum would be unstable with respect to separation into two phases, one of whose composition gave a separation nearer to the minimum. The argument cannot be faulted granted thermodynamic control of the ordering in these structures. It is, however, far from certain that kinetic factors do not play a decisive role in the structure of these compounds. [Pg.118]

Exploitation of commercially available analogues of the selected hits is often an early step in the first round of SAR studies. This is usually followed by the use of basic medicinal chemistry to modify these analogues to sample a reasonable fraction of the overall chemical space. In parallel it is essential to spend time researching synthetic routes to generate the basic scaffold and selected syn-thons with the objective to incorporate more, extended, or diverse functional groups and thns expand the sampled chemical space considerably. [Pg.89]

In general, the steps of the SPSA toward the computation of the correlated wavefunction for each state and the property under consideration are as follows (adjustments in special cases are inevitable) Once is established with self-consistent orbitals that are numerically accurate, one should seek the form of the part of the remaining wavefunction that results from the action on the Fermi-sea of two operators The Hamiltonian and the operator of the property that is being studied. This provides the information to first order beyond the MCHF (or nearly so) on the symmetry and the spatial characteristics of the function space that is created by the action of the two operators. The final result for the total wavefunction is obtained to all orders via diagonalization of the total matrix after judicious choices and... [Pg.50]

The principal contribution to (, D xI//) comes from the first term, (xI/ D xI/ ). Furthermore, since the coefficients of and of are, according to the criterion of Eq. (8), completely dominant, the next two terms of Eq. (10) dictate the part of the function spaces of and of which are connected directly with the zero-order Fermi-sea components and therefore contribute to ( Ti D xI//) the most. Note that the recognition of fhese function spaces from direct dipole connection involves the consideration of N-electron integrals and not just one-electron dipole (or quadrupole, etc) integrals. Therefore, nonorthonormality (NON) between the two sets of orbitals also becomes a criterion of selection of the correlation components. [Pg.56]

X If symbolizes fhe "asymptotic" correlation that is function spaces that represent the energetically open channels and contain the information about the interaction of fhe free electrons with the core state and about the possible interchannel couplings. It is zero when the state is discrete. For quantities where the open continuum is important, such as the energy-dependent photoabsorption cross-sections, or for fhe full description of resonance states, the proper computation and consideration of X are essential. [Pg.372]

This was carried out by Eric A. ComelL Carl E. Wieman. and Wotfgang Ketterle (who received the Nobel Prize in 2001 for discovering a new state of matted ). In the Bose condraisate, the bosons (alkali metal atoms) are in the same place in a peculiar sense. The total wave function for the bosons was, to a first approximation, a product of identical nodefess wave functions for the particular bosons (this ensures proper symmetry). Each of the wave functions extends considerably in space (the Bose condraisate is as large as a fraction of a millimetre), but all have been centered in the same point in space. [Pg.36]

Conitzer Sandholm [31] propose automated mechanism design, in which a computational method is used to design mechanisms with respect to highly-enumerative description of the function space and agent type space. The challenge in this automated MD approach is to develop structured representations of the problem to constrain the input size to the optimization. However, automated MD cannot solve the wider issues presented by the second two problems because it is only applicable to direct revelation mechanisms and because it continues to ignore computational considerations in the formulation of the problem. [Pg.201]

A number of novel techniques based on finite elements have come to forefront recently. The characteristic of these methods is that they work in coordinate rather than function space. These methods have the advantage that the easy correlation between the potential and points used in the calculation can yield considerable physical insight. This insight can be used both for interpretation and for adapting the method to a particular problem of interest. [Pg.324]

We shall limit our attention to spherical regions and occasionally to planar regions. With the geometry in its simplest form, the analysis will be directed at the nonlinearities induced by the chemical reactions. Most of the results could be extended to regions of arbitrary shape. Such extensions, however, would be very tedious requiring the use of more complex function spaces and the consideration of questions of boundary smoothness. [Pg.45]

The conventional stirred-tank reactor is an agitated vessel, typically a jacketed pressure vessel, and often with provisions for reflux of a solvent or monomer. The continuous-feed version is the CSTR. Continuous operation is typical of high-volume polymers but large batch and fed-batch stirred-tank reactors are occasionally used. Reactors other than stirred tanks may be functionally equivalent to stirred tanks. Loop reactors are widely used in the polymer industry, especially for solution and slurry olefin polymerizations the agitator in the stirred tank is replaced with a circulation pump. The loop many consist of jacketed pipe or there may be heat exchangers and even flash vessels in the loop. The loop may consist of many legs for space considerations, but the legs are connected in series and there is only one circulation pump. [Pg.537]

Contingent upon the final mission, the overall service life was identified as a minimum of 12 years to a maximum of 20 year of maintenance free operation while maintaining functional performance and mechanical integrity. Based on pipe size, operational environment, and ambient environment this is a challenging requirement. Typically, a spacecraft design would include redundant valves, operators or systems to ensure that critical functions could be performed for this duration. Redundancy must be balanced against mass and space considerations for the overall spaceship. [Pg.439]

T is a rotational angle, which determines the spatial orientation of the adiabatic electronic functions v / and )/ . In triatomic molecules, this orientation follows directly from symmetry considerations. So, for example, in a II state one of the elecbonic wave functions has its maximum in the molecular plane and the other one is perpendicular to it. If a treatment of the R-T effect is carried out employing the space-fixed coordinate system, the angle t appearing in Eqs. (53)... [Pg.520]

In the strictest meaning, the total wave function cannot be separated since there are many kinds of interactions between the nuclear and electronic degrees of freedom (see later). However, for practical purposes, one can separate the total wave function partially or completely, depending on considerations relative to the magnitude of the various interactions. Owing to the uniformity and isotropy of space, the translational and rotational degrees of freedom of an isolated molecule can be described by cyclic coordinates, and can in principle be separated. Note that the separation of the rotational degrees of freedom is not trivial [37]. [Pg.553]

Elevated Flare Location, Spacing and Height - Ijocation, spacing and height of elevated flares are a function of permissible radiant heat densities, possible burning liquid fall-out, and pollution considerations. Design requirements are as follows ... [Pg.251]

All fluid properties are functions of space and time, namely p(x, y, z, t), p(x, y, z, t), T(x, y, z, t), and u(x, y, z, t) for the density, pressure, temperature, and velocity vector, respectively. The element under consideration is so small that fluid properties at the faces can be expressed accurately by the first two terms of a Taylor series expansion. For example, the pressure at the E and W faces, which are both at a distance l/26x from the element center, is expressed as... [Pg.788]


See other pages where Functions spacing considerations is mentioned: [Pg.152]    [Pg.116]    [Pg.44]    [Pg.173]    [Pg.629]    [Pg.79]    [Pg.74]    [Pg.588]    [Pg.44]    [Pg.149]    [Pg.256]    [Pg.266]    [Pg.348]    [Pg.237]    [Pg.74]    [Pg.562]    [Pg.514]    [Pg.521]    [Pg.133]    [Pg.516]    [Pg.585]    [Pg.104]    [Pg.566]    [Pg.247]    [Pg.17]    [Pg.391]    [Pg.122]   
See also in sourсe #XX -- [ Pg.214 , Pg.219 ]




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