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Zero Measurement

The right-hand side of this equation is exactly the quantity that Eq. (4-289), the Gibbs/Duhem equation, requires to be zero for consistent data. The residual on the left is therefore a direct measure of deviations from the Gibbs/Diihem equation. The extent to which values of this residual fail to scatter about zero measures the departure of the data from consistency with respect to this equation. [Pg.537]

The characterization of the laser pulse widths can be done with commercial autocorrelators or by a variety of other methods that can be found in the ultrafast laser literature. " For example, we have found it convenient to find time zero delay between the pump and probe laser beams in picosecond TR experiments by using fluorescence depletion of trans-stilbene. In this method, the time zero was ascertained by varying the optical delay between the pump and probe beams to a position where the depletion of the stilbene fluorescence was halfway to the maximum fluorescence depletion by the probe laser. The accuracy of the time zero measurement was estimated to be +0.5ps for 1.5ps laser pulses. A typical cross correlation time between the pump and probe pulses can also be measured by the fluorescence depletion method. [Pg.134]

Since in this problem not only the limit but also the character of convergence matters we conclude that consistent homogenization of the micromodel should lead to a description in a broader functional space than is currently accepted. One interesting observation is that the concave part of the energy is relevant only in the region with zero measure where the singular, measure valued contribution to the solution is nontrivial (different from point mass). We remark that the situation is similar in fracture mechanics where a problem of closure at the continuum level can be addressed through the analysis of a discrete lattice (e.g. Truskinovsky, 1996). [Pg.186]

Because of the choice of enumeration, the vectors of logarithms of reaction rate constants form a convex cone in which is described by the system of inequalities lnfc2i> lnfc,y, (/,/)t (2,1). For each of the possible auxiliary systems (Figure 4) additional inequalities between constants should be valid, and we get four correspondent cones in These cones form a partitions of the initial one (we neglect intersections of faces which have zero measure). Let us discuss the typical behavior of systems from these cones separately. (Let us remind that if in a cone for some values of coefficients dp then,... [Pg.149]

Figure 8.4. Choice of a limit of detection (LOD) at which the probabilities of Type I and Type errors are equal at Lcrlt. The distributions are, from left to right, measurements of a blank with analyte concentration zero, measurements of a sample of concentration Lcrit, and measurements of a sample of concentration LOD. Figure 8.4. Choice of a limit of detection (LOD) at which the probabilities of Type I and Type errors are equal at Lcrlt. The distributions are, from left to right, measurements of a blank with analyte concentration zero, measurements of a sample of concentration Lcrit, and measurements of a sample of concentration LOD.
Proposition 2. Any standard radiation electromagnetic field in empty space with Faraday 2-form. F, regular in a bounded spacetime domain D, coincides locally with a knot around any point P C D in the following sense. There is a knot with 2-form 3Fkn, such that Fst = Fkn around P, except perhaps ifP is in a zero measure set. The same property holds for Fst. [Pg.236]

The gauge function (8.2.5) contains a logarithmic term, di = —1.2, which guarantees that, for the reduced fractal, do = 1 and a zero measure are compatible with each other. [Pg.213]

Transport and dispersion was evaluated without any form of tuning by comparing a simulation of the ETEX-1 release to the official measurements of surface concentration. To facilitate comparisons with models evaluated during ATMES 11 (Atmospheric Transport Model Evaluation Study) an identical statistical methodology was employed (Mosca et al. 1998). Background values were subtracted so that only the pure tracer concentration was used. Measurements of zero concentration (concentrations below the background level) were included in time series to the extent that they lay between two non-zero measurements or within two before or two after a non-zero measurement. Hereby, spurious correlations between predicted and measured zero-values far away from the plume track are reduced. [Pg.65]

This error propagation method can also be applied to the data points of the high-symmetry form for which the calculated strains should be zero. Measurement errors and imperfect fits of EoS functions will, in practise, contribute to small non-zero values being calculated for the strains. Deviations of more than 1 or 2 esd s from zero often indicates that the original high-symmetry unit-cell parameters were not fitted correctly... [Pg.92]

Put one into the colorimeter and set the reading to zero. Measure the absorbance of the other one and keep that one as the zero check . [Pg.91]

Show that any countable subset of the real line has zero measure. (This generalizes the result of the previous question.)... [Pg.417]

The appearance of regular states embedded in a sea of chaotic states occurs for all quantum systems and may be attributed to near adiabaticity.66,69-73 This concept of adiabaticity, which is crucial for the understanding of many observations on realistic systems, is discussed subsequently. At this point we just note that in the stadium case the regular states are the quantum analogues of the (zero measure) classical periodic orbits. We will present, later in this chapter an heuristic argument for the existence of regular states for all quantum systems that have no continuous spectrum. [Pg.420]

A mathematically more precise concept associated to this property is ergodicity. The stroboscopic map is ergodic if all of its invariant sets (i.e. those that satisfy r(A) = A) have zero measure or their complement has zero measure. A stronger property is mixing that requires that for any two sets A and B the measure n (area or volume) of the intersection satisfies n B) —> /j,(A)/j,(B) for... [Pg.44]

The proportion of fluid elements experiencing a particular anomalous value of the Lyapunov exponent A / A°° decreases in time as exp(—G(X)t). In the infinite-time limit, in agreement with the Os-eledec theorem, they are limited to regions of zero measure that occupy zero volume (or area in two dimensions), but with a complicated geometrical structure of fractal character, to which one can associate a non-integer fractional dimension. Despite their rarity, we will see that the presence of these sets of untypical Lyapunov exponents may have consequences on measurable quantities. Thus we proceed to provide some characterization for their geometry. [Pg.56]

The chaotic saddle and its manifolds are also sets of zero measure with fractal structure. The set of points, seen in Fig. 2.13 corresponding to inflow coordinates with very large, singular, escape times, typically form also a fractal set determined by the intersection of the saddle s stable manifold and the line containing the initial conditions. There is a connection between the dimension of the chaotic saddle and the dimensions of its manifolds. The trajectories on the chaotic saddle have a set of Lyapunov exponents whose number is equal to the dimension of the full space, d. The sum of the Lyapunov exponents is zero due to incompressibility and chaotic dynamics implies... [Pg.61]

Figure 4.9. The A = 123 Sierpinski gasket, a two-dimensional uncountable set with zero measure and Hausdorff (fractal) dimension 3/ 2 = 1.584962... the companion Euclidean lattice referred to in the text is a space filling triangular lattice of (interior valency v = 6. Figure 4.9. The A = 123 Sierpinski gasket, a two-dimensional uncountable set with zero measure and Hausdorff (fractal) dimension 3/ 2 = 1.584962... the companion Euclidean lattice referred to in the text is a space filling triangular lattice of (interior valency v = 6.
Thus, for d > 4, the nature of the asymptotic behaviour is not modified on the contrary, for d < 4, summing divergencies may lead to the appearance of critical exponents. However, this argument is neither very simple nor very rigorous. It is, however, possible to reach the same conclusion in a much simpler and intuitive manner. In fact, let us consider, in a d-dimensional space domain, two simply connected objects with dimensions D and D respectively, and let us assume that they have a random position. If D + D < d, the probability that these objects have a common part has a zero measure. Actually, if they cut across each other, it is always possible to displace one object infinitesimally, so as to suppress the intersection. For instance, the statistics, of a set of segments (D = 1, D = 1) in a three-dimensional space (d = 3) is quite trivial, whereas in two dimensions, intersection effects have to be taken into account. Thus, in general, two objects feel exclusion effects if and only if D + D > d. [Pg.86]

Figure 6 shows that adsorption levels of foam-forming surfactants can vary widely from near-zero (measurements numbered 1 and 2) to almost... [Pg.273]

In this series of runs, the product acid compositions varied from 9 to 15 percent nitric acid for a feed acid composition of 15 percent nitric acid and from 11 to 21 percent nitric acid with a feed composition of 25 percent. The benzene concentrations in the organic product varied from 60 to 100 percent when pure benzene was used as the feed hydrocarbon and from 25 to 60 percent when the feed hydrocarbon contained 60 percent benzene. No nitrobenzene was detected in the organic product for three of the 20 runs indicating for these particular runs that the rates of nitration were essentially zero. Measurements of the equilibrium solubility of benzene in the acid phase were almost identical regardless of whether nitrobenzene or nitrotoluene was used as the diluent in the hydrocarbon phase. Four additional (and duplicate) runs were also made to estimate the probable levels of experimental errors. This estimate was pooled with an estimate based on earlier runs. [Pg.185]

In the Laboratory Services Branch of the Ontario Ministry of the Environment, the codes Data coded [Pg.320]

Fig. 2.3. Frequency distribution of a random variable, x N(0, 1). Note that x is the deviation from the mean (zero), measured in standard deviations. Fig. 2.3. Frequency distribution of a random variable, x N(0, 1). Note that x is the deviation from the mean (zero), measured in standard deviations.
There are the many open circuit emf studies that have been carried out to search for new solid electrolyte materials. The specimen is placed in contact with electrodes which establish different but known partial pressures Px2 Px2 measured. The ratio of the measured emf E to the thermodynamic voltage calculated from Equation 7 gives a quick estimate of the materials ionic transference number, as implied by Equation 6 cibove. This is an estimate to be sure, because the ratio actually averages the value of tj over the scale. But the method very quickly reveals which materials might best be ruled out for further studies. Indeed, those which persist in registering a zero measured emf are predominantly electronic conductors and probably not much can be done (e.g., by way of doping etc.) to make them into ionic conductors, i.e., solid electrolytes. [Pg.107]

Although assumptions giving (3.267), (3.268) look natural, this is not so, e.g. such S(t) MfiUing (3.264), (3.265) may exist where 5(t) > 0 changes osciUatorily for any time and therefore a limit does not exist. Similarly the existence of limit (3.268) is not clear, e.g. or" in (3.267) may be nonzero on surfaces or lines (sets of zero measure) and such a situation may be obtained even by limitation... [Pg.133]


See other pages where Zero Measurement is mentioned: [Pg.106]    [Pg.684]    [Pg.210]    [Pg.237]    [Pg.238]    [Pg.240]    [Pg.241]    [Pg.190]    [Pg.123]    [Pg.486]    [Pg.227]    [Pg.204]    [Pg.46]    [Pg.475]    [Pg.426]    [Pg.417]    [Pg.538]    [Pg.75]    [Pg.171]    [Pg.215]    [Pg.621]    [Pg.32]    [Pg.1145]   
See also in sourсe #XX -- [ Pg.112 , Pg.113 , Pg.142 , Pg.158 , Pg.360 , Pg.363 ]




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