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Deterministic selection

There is no phase transition at finite temperatures in the asymptotic limit of infinite chains. This is no surprise since no deterministic selection occurs in the absence of differences in rate constants. [Pg.198]

The last definition uses the non-deterministic selection operator choose. This operator assigns to x any index i in the range [1--N] which satisfies the requirement - c[i] A ready i 1) A ready i 2). If no such index exists, x is assigned an arbitrary value in the specified range. This is why, even after the selection, it is necessary to test whether x satisfies the specified requirement. [Pg.33]

Population genetics Deterministic selection equations Stroboscopic method... [Pg.218]

Example 12-4 For the firstPlateau/3 problem, all parameters are of an inductive type, namely list. If we consider the specification of Figure 4-2, both heuristics would point towards L being the best induction parameter. Without this extended specification knowledge, a non-deterministic selection of an induction parameter among L, P, 5 takes place. We assume that L is effectively selected its position w is 1. [Pg.162]

If an intrinsic decomposition is selected, then a decomposition decrement, denoted d, needs to be selected before proceeding to Task F. This is done by non-deterministically selecting a value within the following integer interval ... [Pg.167]

What are the structural forms Task D of Step 2 non-deterministically selects some domain extrapolation hypothesis and extracts the corresponding predefined forms from a typed database. [Pg.194]

Deterministic Randomness. On the one hand, equation 4.8 is a trivial linear difference equation possessing an equally as trivial solution for each initial point Xq Xn = 2"a o (mod 1). Once an initial point is chosen, the future iterates are determined uniquely. As such, this simple system is an intrinsically deterministic one. On the other hand, look again at the binary decimal expansion of a randomly selected a o- This expansion can also be thought of as a particular semi-infinite sequence of coin tosses. [Pg.175]

The issues of selection of the spatial wavelength and the deterministic character of the fine scale features of the microstructure are closely related to similar questions in nonlinear transitions in a host of other physical systems, such as macroscopic models of immiscible displacement in porous media - - the Hele Shaw Problem (15) - and flow transitions in fluid mechanical systems (16). [Pg.300]

Model formulation. After the objective of modelling has been defined, a preliminary model is derived. At first, independent variables influencing the process performance (temperature, pressure, catalyst physical properties and activity, concentrations, impurities, type of solvent, etc.) must be identified based on the chemists knowledge about reactions involved and theories concerning organic and physical chemistry, mainly kinetics. Dependent variables (yields, selectivities, product properties) are defined. Although statistical models might be better from a physical point of view, in practice, deterministic models describe the vast majority of chemical processes sufficiently well. In principle model equations are derived based on the conservation law ... [Pg.234]

Thus, two copies of string 2 in Table 5.8, whose scaled fitness is 2.037, are certain to be made in the first round of selection using stochastic remainder, while at this stage no copies of string 7, whose fitness is 0.850, are made. This deterministic step ensures that every above-average string will appear... [Pg.137]

In the first case, it could be imagined that a protoenzyme on the primeval Earth, which catalysed the polycondensation of amino acids to (proto)proteins, decided for unknown reasons to favour the L-form. This decision would have needed to be passed on to subsequent sequences. The question comes up chance or necessity Could the protoenzyme have selected the D-amino acid with an equal probability Work to find an answer is still in progress. There are many publications on the deterministic hypothesis, both theoretical and experimental. [Pg.248]

We have investigated another procedure for reducing the computational expense of the AIMS method, which capitalizes on the temporal nonlocality of the Schrodinger equation and the deterministic aspect of the AIMS method. Recall that apart from the Monte Carlo procedure that we employ for selecting initial conditions, the prescription for basis set propagation and expansion is deterministic. We emphasize the deterministic aspect because the time-displaced procedure relies on this property. [Pg.471]

Details concerning biofilm growth and activity in sewers are at present not available to the same extent as is the case for the suspended biomass. Therefore, a simple expression for biofilm growth and respiration compared to other well-known deterministic biofilm models, e.g., as described by Gujer and Wanner (1990), is selected. [Pg.108]

Air quality control r ions (aqcr s), 128 Air quality prediction models, 195, 678-79 airshed photodiemical, 218 balance-equation, 205 box, 213-15, 219 classification of, 200-205 criteria for selecting, 219-20 deterministic, 203 dispersion, 205 explanation of, 1% for episode control, 202 for land-use planning, 201-2 for physiochemical transformations, 208-10... [Pg.708]

In the following text, various studies will be described, which attempt to establish a scientific rationale for the selection of the interspecies assessment factor. Based on these studies, it can be concluded that a species-specific default factor based on differences in caloric requirement (see Table 5.4) should be used for interspecies extrapolation regarding metabolic size. The remaining interspecies differences should preferentially be described probabilistically, or a deterministic default factor of 2.5 could be used for extrapolation of data from rat studies to the human situation. [Pg.237]

Table 8.1 shows the stochastic model solution for the petrochemical system. The solution indicated the selection of 22 processes with a slightly different configuration and production capacities from the deterministic case, Table 4.2 in Chapter 4. For example, acetic acid was produced by direct oxidation of n-butylenes instead of the air oxidation of acetaldehyde. Furthermore, ethylene was produced by pyrolysis of ethane instead of steam cracking of ethane-propane (50-50 wt%). These changes, as well as the different production capacities obtained, illustrate the effect of the uncertainty in process yield, raw material and product prices, and lower product... [Pg.167]

The results of the model considered in this Chapter under uncertainty and with risk consideration, as one can intuitively anticipate, yielded different petrochemical network configurations and plant capacities when compared to the deterministic model results. The concepts of EVPI and VSS were introduced and numerically illustrated. The stochastic model provided good results as the objective function value was not too far from the results obtained using the wait-and-see approach. Furthermore, the results in this Chapter showed that the final petrochemical network was more sensitive to variations in product prices than to variation in market demand and process yields when the values of 0i and 02 were selected to maintain the final petrochemical structure. [Pg.170]

If thermal fluctuations were taken into account, the regular patterns selected by this kinetic mechanism would be expected to be less sharp. In particular, when wjwa, is not so small, the effects of mass conservation are spread out over many terraces and several terraces in front of the step bunch become larger than These would be particularly advantageous sites where thennal nucleation could occur, even before the induced width of the terrace as predicted by the deterministic models would exceed Wc. Thus nucleation sites and times are less precisely determined in this case, and we... [Pg.208]

We can understand better this asymptotics by using the Markov chain language. For nonseparated constants a particle in has nonzero probability to reach and nonzero probability to reach A, . The zero-one law in this simplest case means that the dynamics of the particle becomes deterministic with probability one it chooses to go to one of vertices A, A3 and to avoid another. Instead of branching, A2 A and A2 A3, we select only one way either A2 A] or A2 A3. Graphs without branching represent discrete dynamical systems. [Pg.130]

The question of determinateness presents itself as follows Let the initial (t = 0) values of all the macroscopically independent macroscopic variables be given the equations of macroscopic physics (thermal and hydro-dynamic equations, etc.) show that these variables evolve deterministically with t 0. Yet there are infinitely many different probability densities ( ")t = 0 which have the moments, etc., coinciding with the set of given initial macroscopic values. Each evolves (by Liouville s equation) differently, and hence may induce a different set of macroscopic expected values at / > 0. By what principle of natural selection is the class of probability densities so restricted as to restore macroscopic determinacy ... [Pg.39]


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See also in sourсe #XX -- [ Pg.229 ]




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