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Correspondence principle described

The procedure described above is an application of the time-temperature correspondence principle. By shifting a set of plots of modulus (or compliance) versus time (or frequency) at any temperature (subscript 1) along the log t axis, we obtain the value of that mechanical property at another time and temperature (subscript 2). Using the shear modulus as an example, the time-temperature correspondence principle states... [Pg.258]

The basis upon which this concept rests is the very fact that not all the data follows the same equation. Another way to express this is to note that an equation describes a line (or more generally, a plane or hyperplane if more than two dimensions are involved. In fact, anywhere in this discussion, when we talk about a calibration line, you should mentally add the phrase ... or plane, or hyperplane... ). Thus any point that fits the equation will fall exactly on the line. On the other hand, since the data points themselves do not fall on the line (recall that, by definition, the line is generated by applying some sort of [at this point undefined] averaging process), any given data point will not fall on the line described by the equation. The difference between these two points, the one on the line described by the equation and the one described by the data, is the error in the estimate of that data point by the equation. For each of the data points there is a corresponding point described by the equation, and therefore a corresponding error. The least square principle states that the sum of the squares of all these errors should have a minimum value and as we stated above, this will also provide the maximum likelihood equation. [Pg.34]

In all three equations Ex and E > are now the complex moduli the storage and loss moduli for the blend are obtained by direct substitution into these equations and separation of the real and imaginary parts to obtain separate mixture rules for each. Analytical expressions have been obtained for these, but they are lengthy and cumbersome. All the calculations described, therefore, were carried out by computer. The substitution of complex moduli into the solution of the equivalent purely elastic problem is justified by the correspondence principle of viscoelastic stress analysis (6). [Pg.216]

Recently, several new anti-odour finishing products have become available that correspond to the principles described above. Some of these products are also recommended and used for fragrance finishes. [Pg.192]

The generalized stress-strain relationships in linear viscoelasticity can be obtained directly from the generalized Hooke s law, described by Eqs. (4.85) and (4.118), by using the so-called correspondence principle. This principle establishes that if an elastic solution to a stress analysis is known, the corresponding viscoelastic (complex plane) solution can be obtained by substituting for the elastic quantities the -multiplied Laplace transforms (8 p. 509). The appUcation of this principle to Eq. (4.85) gives... [Pg.221]

According to the correspondence principle, the equation describing a viscoelastic beam under transversal and longitudinal effects is given by... [Pg.812]

There is partial localization of the valence density in methane. The condensation into four partially localized pairs of electrons arranged along four tetrahedral axes is a result of the combined effects of the ligand field and the Pauli exclusion principle described above. Most important is that this partial localization of the pair density is reflected in the properties of the VSCC of the carbon atom which undergoes a corresponding condensation into four local concentrations of electronic charge. These properties of the pair density are not just the result of the tetrahedral symmetry of the ligand field in methane because, as we will now see, the Fermi hole exhibits the same behaviour in the ammonia molecule. [Pg.347]

Comparison of equations (2) and (4) show that the radiation from the bond state described by WKB obeys the correspondence principle. [Pg.23]

Using the principles described previously, the trisaccharide (See Fig. 7, O Neill et al., 1986a) was shown to have the structure 17. Comparable tetra- and trisaccharides in which the terminal a-L-Man/) residue was replaced by terminal a-L-Rhap were also detected in the products of -elimination. The two trisaccharides are probably formed by a P-eliminative degradation of the corresponding tetrasaccharides (see 16 and 17). [Pg.123]

Figure 6.16 Electron Density Map Example of an electron density map generated computationally from electron density data that has been derived by the application of the equations and principles described in the main text from X-ray crystallographic scattering data. The electron density map corresponds with part of the active site of an enzyme LysU (see next Fig. 6.19 Chapters 7 and 8) from the organism Escherichia coli. This electron density map has been "fitted" with the primary sequence polypeptide chain of LysU (colour code - carbon yellow oxygen red nitrogen blue). Once an electron density map has been determined, fitting of the known primary sequence of the biological macromolecule to the electron density map is the final stage that leads to a defined three-dimensional structure (from Onesti et al., 1995, Fig. 9). Figure 6.16 Electron Density Map Example of an electron density map generated computationally from electron density data that has been derived by the application of the equations and principles described in the main text from X-ray crystallographic scattering data. The electron density map corresponds with part of the active site of an enzyme LysU (see next Fig. 6.19 Chapters 7 and 8) from the organism Escherichia coli. This electron density map has been "fitted" with the primary sequence polypeptide chain of LysU (colour code - carbon yellow oxygen red nitrogen blue). Once an electron density map has been determined, fitting of the known primary sequence of the biological macromolecule to the electron density map is the final stage that leads to a defined three-dimensional structure (from Onesti et al., 1995, Fig. 9).
We now turn to methods which do not attempt to obtain the characteristic values without the characteristic vectors. Of course, if the characteristic values have been obtained by the methods of Secs. 9-3 or 9-4, one may insert any given Xj, and solve the simultaneous equations. However, if one requires characteristic vectors as well as the X s, for problems where r > 3, it is much better to use one of the methods to be described in this and the following sections. Furthermore, the subsequent methods can all be used in conjunction with the principle described in Sec. 9-6, namely, that an approximate solution of the simultaneous equations, i.e., characteristic vector, V, substituted in Eq. (18), Sec. 9-6, yields a relatively accurate estimate of the corresponding X. ... [Pg.117]

A = /jc/ photon> h has the form of de Broglie s equation AdB =h/p but is written for radiation instead of matter. We ve used de Broglie s equation to devise a correspondence principle to tell us when we need to use quantum mechanics to describe a system. Does this form of Planck s law suggest a version of the correspondence principle appropriate for radiation ... [Pg.63]


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See also in sourсe #XX -- [ Pg.47 ]




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Correspondence principle

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