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Theory deterministic

Remark. It is easily seen that the second term of (5.2) by itself causes the norm of if/ to change. In order that this is compensated by the fluctuating term the two terms must be linked, as is done by the relation U = V V. This resembles the classical fluctuation-dissipation theorem, which links both terms by the requirement that the fluctuations compensate the energy loss so as to establish the equilibrium. The difference is that the latter requirement involves the temperature T of the environment that makes it possible to suppress the fluctuations by taking T = 0 without losing the damping. This is the reason why in classical theory deterministic equations with damping exist, see XI.5. [Pg.445]

Ray, W. H., 912, J. Macromol. Sci.-Revs. Macromol. Chem., C8, 1 56 Reklaitis, G. V, 1983, Introduction to Mass and Energy Balances. New York Wiley Robert, C., 2001, The Bayesian Choice, second edition. New York Springer Sontag, E. D., 1990, Mathematical Control Theory Deterministic Finite Dimensional Systems. New York Springer-Verlag... [Pg.462]

The movement from the deterministic design criteria as described by equation 4.1 to the probability based one described by equation 4.2 has far reaching effects on design (Haugen, 1980). The particular change which marks the development of modern engineering reliability is the insight that probability, a mathematical theory, can be utilized to quantify the qualitative concept of reliability (Ben-Haim, 1994). [Pg.135]

A final comment on the interpretation of stochastic simulations We are so accustomed to writing continuous functions—differential and integrated rate equations, commonly called deterministic rate equations—that our first impulse on viewing these stochastic calculations is to interpret them as approximations to the familiar continuous functions. However, we have got this the wrong way around. On a molecular level, events are discrete, not continuous. The continuous functions work so well for us only because we do experiments on veiy large numbers of molecules (typically 10 -10 ). If we could experiment with very much smaller numbers of molecules, we would find that it is the continuous functions that are approximations to the stochastic results. Gillespie has developed the stochastic theory of chemical kinetics without dependence on the deterministic rate equations. [Pg.114]

Gerald t Hooft, in a speculative 1988 paper [thooft88], suggests that a suitably defined deterministic, local reversible cellular automata might provide a viable formalism for constructing field theories at the Planck scale. [Pg.651]

Fredkin points out that even if a preferred frame, or underlying lattice, is found, its implications are in one sense only philosophical the integrity of the theory of relativity remains intact, it is only our philosophical perspective that changes. Similarly, if a deterministic RUCA-like rule is the basis of the real physics, it does not mean that we should all throw away our quantum mechanics texts. On the other, if the finite nature hypothesis is correct and a RUCA-like rule exists and can be found, it should in principle be able to supply us with values of all of the fundamental constants of physics. [Pg.668]

In a famous paper, Bell [bell64] showed that locality and the notion that the components of the particles spins are determinate are fundamentally incompatible with the spin correlations as predicted by quantum mechanics. Bell s result, in effect, rules out the possibility of having a local, deterministic theory. [Pg.677]

The main problem is to calculate (/ (q, H-r)/(q, t- -r)) of Eq. (2). To achieve this goal, one first considers E(r,f) as a well-defined, deterministic quantity. Its effect on the system may then be determined by treating the von Neumann equation for the density matrix p(f) by perturbation theory the laser perturbation is supposed to be sufficiently small to permit a perturbation expansion. Once p(i) has been calculated, the quantity... [Pg.267]

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]

Periodic boundary conditions, Monte Carlo heat flow simulation, nonequilibrium molecular dynamics, 79—81 Periodic-orbit dividing surface (PODS) geometric transition state theory, 196-201 transition state trajectory, 202-213 Perturbation theory, transition state trajectory, deterministically moving manifolds, 224-228... [Pg.285]

Scalar equations, transition state trajectory deterministically moving manifolds, 224—228 stochastically moving manifolds, 214—222 Scattering theory, two-pathway excitation,... [Pg.287]

Floudas CA (2000) Deterministic Global Optimization Theory, Methods and Applications, Kluwer Academic Publishers. [Pg.15]

Evolutionary psychologists go to some lengths to insist that, unlike exponents of earlier versions of social Darwinism, they are not genetic determinists, or as they sometimes put it, nativists. Rather, they argue that the nature/nurture dichotomy is a fallacious one. Instead, they seek to account for what they believe to be universals in terms of a version of Darwinian theory - a version which in practice owes more to Dawkins reductive fundamentalism than it does to Darwin s own more pluralistic and observation-rich insights. [Pg.282]

According to Stuart A. Kauffman (1991) there is no generally accepted definition for the term complexity . However, there is consensus on certain properties of complex systems. One of these is deterministic chaos, which we have already mentioned. An ordered, non-linear dynamic system can undergo conversion to a chaotic state when slight, hardly noticeable perturbations act on it. Even very small differences in the initial conditions of complex systems can lead to great differences in the development of the system. Thus, the theory of complex systems no longer uses the well-known cause and effect principle. [Pg.244]

Valiant, L. G., "The Decidability of Equivalence for Deterministic Finite-Turn Pushdown Automata," Proceedings 6th Annual ACM Symposium on Theory of Computing, Seattle, Washington, (1974) 27-32. [Pg.367]

Daw, C. S., and Harlow, J. S., Characteristics of Voidage and Pressure Signals from Fluidized Beds using Deterministic Chaos Theory, Proc. 11th Int. Conf. FluidizedBedComb., 2 777 (1991)... [Pg.105]

In most natural situations, physical and chemical parameters are not defined by a unique deterministic value. Due to our limited comprehension of the natural processes and imperfect analytical procedures (notwithstanding the interaction of the measurement itself with the process investigated), measurements of concentrations, isotopic ratios and other geochemical parameters must be considered as samples taken from an infinite reservoir or population of attainable values. Defining random variables in a rigorous way would require a rather lengthy development of probability spaces and the measure theory which is beyond the scope of this book. For that purpose, the reader is referred to any of the many excellent standard textbooks on probability and statistics (e.g., Hamilton, 1964 Hoel et al., 1971 Lloyd, 1980 Papoulis, 1984 Dudewicz and Mishra, 1988). For most practical purposes, the statistical analysis of geochemical parameters will be restricted to the field of continuous random variables. [Pg.173]

In parallel with the studies described above, which concern perfectly deterministic equations of evolution, it appeared necessary to complete the theory by studying the spontaneous fluctuations. Near equilibrium, any deviation is rapidly damped but near a bifurcation point, a fluctuation may may lead the system across the barrier. The fluctuation is then stabilized, or even amplified this is the origin of the phenomenon which Prigogine liked calling creation of order through fluctuations. More specifically, one witnesses in this way a step toward self-organization. [Pg.13]

Adopting Eu=ql and Ey=0, then Equation l6 reduces to Equation 5 With Eu=ql and Ey=rl, Equation l6 has a format which is identical to the solution derived in (2T) through a deterministic minimum least squares approach for time-invariant systems. This is to be expected, because the Wiener filtering technique may be in fact Included as part of the general theory of least squares. [Pg.291]


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See also in sourсe #XX -- [ Pg.183 , Pg.200 , Pg.205 , Pg.206 ]




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