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Sketching advantages

It can be argued that the main advantage of least-squares analysis is not that it provides the best fit to the data, but rather that it provides estimates of the uncertainties of the parameters. Here we sketch the basis of the method by which variances of the parameters are obtained. This is an abbreviated treatment following Bennett and Franklin.We use the normal equations (2-73) as an example. Equation (2-73a) is solved for <2o-... [Pg.46]

It would be an advantage to have a detailed understanding of the glass transition in order to get an idea of the structural and dynamic features that are important for photophysical deactivation pathways or solid-state photochemical reactions in molecular glasses. Unfortunately, the formation of a glass is one of the least understood problems in solid-state science. At least three different theories have been developed for a description of the glass transition that we can sketch only briefly in this context the free volume theory, a thermodynamic approach, and the mode coupling theory. [Pg.100]

From a software point of view, it is desirable to have a well-structured hierarchical description for the different biomacromolecules in the simulation system. Such a hierarchy should provide data structures and access functions on the atomic, residue, molecule, and system levels. This allows routines for the evaluation of energy terms to be set up at the level of residue pairs. Experience [14] suggests that this setup is advantageous since it provides a route to easily and intuitively implement the computational algorithms sketched below. [Pg.55]

Write out the complete reactions for production of PMMA and phenol-formaldehyde, as sketched in Figure 11-11. What are the advantages and disadvantages of an integrated chemical plant compared to separate plants to prepare individual chemicals and polymers ... [Pg.471]

One advantage of the idea of autopoiesis is its extreme simplicity. This comes at the cost of a lack of structural and mechanistic details. Ganti s chemoton provides a more detailed and more complex view of the unit of cellular life (Ganti, 1975 2003). Let s now sketch the basic theory of the chemoton in order to draw a comparison with autopoiesis. [Pg.177]

More realistic sketches of the cross section of a steam generator are in Figure 1.4. Part (a) of this figure illustrates the process of natural circulation of water between an upper steam drum and a lower drum provided for the accumulation and eventual blowdown of sediment. In some installations, pumped circulation of the water is advantageous. [Pg.9]

Being able to control u>0 and uir is not sufficient if we don t know their values. The repetition rate u>r is simply measured by a photo detector at the output of either the laser or the fiber. To measure the offset frequency oj0, a mode nu>r + u>0 on the red side of the comb is frequency doubled to 2(nu>r + oj0). If the comb contains more than an optical octave there will be a mode with the mode number 2n oscillating at 2nu>r+u>0. As sketched in Fig. 3 we take advantage of the fact that the offset frequency is common to all modes3 by creating the beat frequency (=difference frequency) between the frequency doubled red mode and the blue mode to obtain u>0. This method allowed the construction of a very simple frequency chain [14,15,16,17,18,19] that eventually operated with a single laser. It occupies only 1 square meter on our optical table with considerable potential for further miniaturization. At the same time it supplies us with a reference frequency grid across much of the visible and infrared spectrum. [Pg.134]

Mukherjee/69/, use of the sufficiency conditions (7.3.9) amounts in effect to assuming that ft is a valence-universal wave-operator. In fact Haque has explicitly demonstrated/123/ that the use of a valence-universal ft in the Fock-space Bloch equation leads automatically to eqn (7.3.9) with the ad-hoc sufficiency requirement. We give the sketch of a general proof here, since it shows that the extra information content of a Fock-space ft, as opposed to a Hilbert space, can be used to advantage for ensuring the connectivity of the cluster amplitudes of S/93/. For a valence-universal ft, the Fock-space Bloch equation (6.1.15) leads to... [Pg.347]

An important aspect of the MO model is the choice of the molecular orbitals that are used for discussing the properties of molecules. Early work considered either qualitative sketches of MOs or molecular orbitals, which came from EHT calculations. Later work used Hartree-Fock (HF) orbitals for the MO models. The latter have the disadvantage that the correlation energy is not considered although correlation effects can be very important for the stmcture and reactivity of molecules. The advent of DFT calculations introduced also the use of Kohn-Sham (KS) orbitals for MO models. The advantage of KS orbitals is that correlation effects are... [Pg.1243]


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See also in sourсe #XX -- [ Pg.72 ]




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Sketches

Sketching

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