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Infinite-valued systems

The performance of NLP solvers is strongly influenced by the point from which the solution process is started. Points such as the origin (0, 0,...) should be avoided because there may be a number of zero derivatives at that point (as well as problems with infinite values). In general, any point where a substantial number of zero derivatives are possible is undesirable, as is any point where tiny denominator values are possible. Finally, for models of physical processes, the user should avoid starting points that do not represent realistic operating conditions. Such points may cause the solver to move toward points that are stationary points but unacceptable configurations of the physical system. [Pg.327]

An average expectance of additional chains v, which is greater than unity allows for a non-zero probability of the randomly selected crosslinked chain belonging to an infinitely large system [79,83]. This gives the critical value of crosslinking density ac corresponding to the gel point. [Pg.682]

In an ideal system, the transmission contrast ratio is 100%, the transmission dynamic range goes to an infinite value, and the transmission cutoff is zero. [Pg.328]

A.4.11 Discrete probability distributions model systems with finite, or countably infinite, values, while a continuous probability distribution model systems with infinite possible values within a range. [Pg.19]

The order parameter cumulant data [217] for different system sizes show a crossing point at about 0.65, and they do not display a minimum even for the largest system size L = 180. The universal value for the intersection point assuming the respective continuous three-state Potts scenario of Ref. 56 would be U 0.65 (see Ref. 69 in Ref. 217). Assuming a first-order transition, the crossing point Ua> Tc,oss) is expected to occur at around 0.61 for the infinitely large system, and the first-order size correction estimated based on (3.24)-(3.25) yields a value of 0.67. Similarly to the outcome for the energy cumulant, it was concluded [217] that the behavior of the order parameter cumulant could be rationalized for both the first-order and the proposed [56] continuous transition scenarios. [Pg.302]

For bound states, it has to tend to zero at infinite values of any of the coordinates (Fig. 2.6h.i). because such a system is compact and does not disintegrate in space. In consequence (from the probabifistic interpretation), the wave function is square integrable i.e., ( ) < oo. [Pg.81]

Experience has shown that a quantitative description of the properties of atomic systems is not possible on the basis of the laws of classical physics. Quantum physics represents an attempt at a generalisation of these laws in the sense that a certain constant, Planck s constant, has a finite value A== 6 55.10 erg sec in contrast to classical physics, corresponding to the limit A=0, just as relativistic physics is a generalisation of non-relativistic physics, the latter arising from the former by passing from a finite value of the velocity of light c to an infinite value. Quantum physics in its present form appears adequate for dealing with all questions in which the internal constitution of the electron and the atomic nuclei as well as the theory of relativity need not be taken into ac-... [Pg.2]

Note that the above mechanism cannot be fulfilled in our experiments, because the induction time of the reaction is quasi-infinite so that the upper limit of the bistable domain, Rg p, takes a quasi-infinite value (10-12), Then it would take a piece of gel of an infinite size to have the reaction switch spontaneously from the unreacted to the reacted state, and the oscillation loop cannot be closed. Work is now in progress in order to devise an experimental system producing oscillations through this mechanism. [Pg.92]

It should be noted that in the case of thermal equilibrium with the lattice the levels of highest enei y are always less populated than the lower ones. At the saturation it is possible to create situations in which the highest levels are more populated than the lower ones. If one assumes Equation 19 to be still valid this situation corresponds to negative spin temp>eratures. The spin system is not then of course in equilibrium with lattice because negative temperature is only defined for systems with an upper boimd in the energy sp>ectrum. The Figure 2 illustrates the concept of spin temperature for the case S = 1/2 and positive, negative and infinite values of temperature. [Pg.27]

Thermal evolution would be the primary processing history for the various systems of interest. The ramp-and-hold thermal history can be incorporated in the model simulation, based on the ratio of the ramp time to the characteristic time of the behavior of the system (such as phase separation). This method has been employed for spinodal decomposition with temperature drop in a polymer/solvent system (Laxminarayan and Caneba, 1991), and a Deborah number (De) is used to signify the ratio of the characteristic phase separation time to the temperature ramp characteristic time. Thus, if De is infinite, the system would be under sudden quenching. Results of the work for a nonreactive binary polymer/solvent system established bounds for dimensionless interdomain distance (interdomain distance divided by its value during sudden quenching) vs De. Also, the dimen-... [Pg.292]

Jellium is a hypothetical electrically neutral, infinite-volume system consisting of an infinite number of interacting electrons moving in a space throughout which positive charge is continuously and uniformly distributed. The number of electrons per unit volume in the jellium has a nonzero constant value p. The electrons in the jellium constitute a homogeneous (or uniform) electron gas. Taking the functional derivative of we find [Eqs. (16.50) and (16.51)]... [Pg.560]

There is still another complication. The microrheology has been developed for infinitely diluted systems. Many experimental studies have shown that during the dispersion processes the drop size decreases until an equilibrium value is reached. Its experimental value is usually larger than predicted. The difference, originating in drop coalescence, increases with concentration [Huneault et al., 1993], The coalescence is enhanced by the same factors that favor the breakup, i.e., high shear rates, reduced dispersed-phase viscosity, convergent flow, etc. [Pg.26]

In closed systems reactant consumption blurs the distinction between thermal runaway and quiescent behaviour. In all cases temperatures at first increase in time but there is no longer a set of curves reaching infinite values. All temperature histories pass through a single maximum value (T - or 0 ) and subsequently fall back to ambient. Our problem becomes one of understanding sensitivity, not locating a discontinuity. Nevertheless, the quantities introduced above ( p, 0, B) form the appropriate framework for investigation. We consider how 0 depends upon the value of p, and we identify and define maximum sensitivity of events to initial conditions as those for which d0 /d li has its maximum value. [Pg.10]

As has been mentioned already (see Section 2.4) the resonance capture by in a homogeneous natural uranium reactor is too great to permit even an infinitely large system of this type to attain criticality the maximum possible value of for the reactor is in fact of the order of 0.74. It was... [Pg.100]


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See also in sourсe #XX -- [ Pg.20 , Pg.25 ]




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