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Stationary average

While in the linear response regime, modulus and density correlator are measurable quantities outside the linear regime, both quantities serve as tools in the ITT approach only. The transient correlator and shear modulus provide a route to the stationary averages because they describe the decay of equilibrium fluctuations under external shear and their time integral provides an approximation for the stationary distribution function. Determination of tlie frequency dependent moduli under large amplitude oscillatory shear has only recently become possible [58], and requires an extension of the present approach to time dependent shear rates in (3) [59],... [Pg.74]

In order to define dynamical averages and to describe methods to calculate such quantities, we introduce a straightforward approach based on replacing dynamical averages with stationary averages of an observable that incorporates the action of the flow map. Let a and b be mappings from the phase space to the same Euclidean space, and define the temporal correlation of a and b (on the surface of energy E) by... [Pg.203]

The interpretation of a dynamical average (e.g. an autocorrelation function) as a stationary average means that we can apply the perturbation result to such computations as well. For more discussion of numerical averages and computation of correlation functions, see [338],... [Pg.209]

If we start with an initial distribution po which is different than peq, what sort of behavior do averages with respect to the evolving distribution p(X, t) exhibit If they converge to a stationary average, at what rate Does it matter if we start from a distribution near to (in a suitable sense) or far away from an invariant distribution ... [Pg.247]

Gaussian distributions, where we have invariant (stationary) averages... [Pg.274]

The adaptive estimation of the pseudo-inverse parameters a n) consists of the blocks C and E (Fig. 1) if the transformed noise ( ) has unknown properties. Bloek C performes the restoration of the posterior PDD function w a,n) from the data a (n) + (n). It includes methods and algorithms for the PDD function restoration from empirical data [8] which are based on empirical averaging. Beeause the noise is assumed to be a stationary process with zero mean value and the image parameters are constant, the PDD function w(a,n) converges, at least, to the real distribution. The posterior PDD funetion is used to built a back loop to block B and as a direct input for the estimator E. For the given estimation criteria f(a,d) an optimal estimation a (n) can be found from the expression... [Pg.123]

These methods, which probably deserve more attention than they have received to date, simultaneously optimize the positions of a number of points along the reaction path. The method of Elber and Karpins [91] was developed to find transition states. It fiimishes, however, an approximation to the reaction path. In this method, a number (typically 10-20) equidistant points are chosen along an approximate reaction path coimecting two stationary points a and b, and the average of their energies is minimized under the constraint that their spacing remains equal. This is obviously a numerical quadrature of the integral s f ( (.v)where... [Pg.2354]

This spatial distribution is not stationary but evolves in time. So in this ease, one has a wavefunetion that is not a pure eigenstate of the Hamiltonian (one says that E is a superposition state or a non-stationary state) whose average energy remains eonstant (E=E2,i ap + El 2 bp) but whose spatial distribution ehanges with time. [Pg.55]

The superpositioning of experimental and theoretical curves to evaluate a characteristic time is reminiscent of the time-tefnperature superpositioning described in Sec. 4.10. This parallel is even more apparent if the theoretical curve is drawn on a logarithmic scale, in which case the distance by which the curve has to be shifted measures log r. Note that the limiting values of the ordinate in Fig. 6.6 correspond to the limits described in Eqs. (6.46) and (6.47). Because this method effectively averages over both the buildup and the decay phases of radical concentration, it affords an experimentally less demanding method for the determination of r than alternative methods which utilize either the buildup or the decay portions of the non-stationary-state free-radical concentration. [Pg.379]

This function measures the correlation of the property A (it) to itself at two different times separated by the time interval t, averaged over the whole trajectory. The auto-correlation function is reversible in time [i.e., CaU) = it)], and it is stationary (i.e., (A(it + t)A(t))... [Pg.54]

Thus, during solute transfer between the phases, (t) is now the average diffusion time (to) and (o) is the mean distance through which the solute diffuses, Le., the depth or thickness of the film of stationary phase (df). Thus,... [Pg.254]

It is seen that equations (13) and (15) are very similar to equation (10) except that the velocity used is the outlet velocity and not the average velocity and that the diffusivity of the solute in the gas phase is taken as that measured at the outlet pressure of the column (atmospheric). It is also seen from equation (14) that the resistance to mass transfer in the stationary phase is now a function of the inlet-outlet pressure ratio (y). [Pg.271]

Similar behavior was observed for LNG clouds during both continuous and instantaneous tests, but average flame speeds were lower the maximum speed observed in any of the tests was 10 m/s. Following premixed combustion, the flame burned through the fuel-rich portion of the cloud. This stage of combustion was more evident for continuous spills, where the rate of flame propagation, particularly for LNG spills, was very low. In one of the continuous LNG tests, a wind speed of only 4.5 m/s was sufficient to hold the flame stationary at a point some 65 m from the spill point for almost 1 minute the spill rate was then reduced. [Pg.149]

PBM (Photochemical Box Model) is a simple stationary single-cell model with a variable height lid designed to provide volume-integrated hour averages of ozone and otlier photochemical smog pollutants for an urban area for a single day of simulation. [Pg.386]

Run a final state-averaged calculation at the fuUy-optimized conical intersection using the 4-31G basis set and P to predict the energies of the two states and view the configuration coefficients. (This step will not be necessary if you chose to use P for the final conical intersection optimization job you ll find the relevant output in the CAS output for the final optimization step, preceding the table giving the stationary point geometry.)... [Pg.235]

One potential problem associated with column coupling in reversed phase is relatively high back-pressure ( 2600 psi at 1 mL miir ). This will place a limit on the flow rate, which in turn limits the further reduction of analysis time. Also, compared to the new polar organic mode, the retention in reversed phase on coupled columns is deviated more from the average retention on the individual stationary phases. [Pg.40]

The second system studied was the separation of the chiral epoxide enantiomers (la,2,7,7a-tetrahydro-3-methoxynaphth-(2,3b)-oxirane Sandoz Pharma) used as an intermediate in the enantioselective synthesis of optically active drugs. The SMB has been used to carry out this chiral separation [27, 34, 35]. The separation can be performed using microcrystalline cellulose triacetate as stationary phase with an average particle diameter greater than 45 )tm. The eluent used was pure methanol. A... [Pg.243]

Another way of obtaining information on the time-averaged mobility of charge carriers on their way across a sample of arbitrary thickness is, to simultaneously measure the current and the stationary charge earners density via transient absorption and to infer the mobility from j-rnpF. Such experiments have been performed on blends of conjugated oligomers derived from /m-siilbene amine and a... [Pg.527]


See other pages where Stationary average is mentioned: [Pg.77]    [Pg.203]    [Pg.261]    [Pg.265]    [Pg.276]    [Pg.46]    [Pg.98]    [Pg.101]    [Pg.77]    [Pg.203]    [Pg.261]    [Pg.265]    [Pg.276]    [Pg.46]    [Pg.98]    [Pg.101]    [Pg.15]    [Pg.694]    [Pg.694]    [Pg.3067]    [Pg.221]    [Pg.222]    [Pg.108]    [Pg.64]    [Pg.307]    [Pg.560]    [Pg.671]    [Pg.42]    [Pg.280]    [Pg.569]    [Pg.252]    [Pg.280]    [Pg.405]    [Pg.269]    [Pg.323]    [Pg.51]    [Pg.615]    [Pg.301]    [Pg.40]    [Pg.209]   
See also in sourсe #XX -- [ Pg.274 ]




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