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Reflection matrix

Principal component analysis (PCA) takes the m-coordinate vectors q associated with the conformation sample and calculates the square m X m matrix, reflecting the relationships between the coordinates. This matrix, also known as the covariance matrix C, is defined as... [Pg.87]

Principal coordinate analysis (PCoorA) [37], on the other hand, operates on the square n X n matrix, reflecting the relationships between the conformations. The... [Pg.87]

In a similar approach, Pimmg and Chen [3] prepared an indexed library of 54 carbamates from a set of nine alcohols and nine isocyanates. The library was prepared as 15 sublibraries in which each of the alcohols and isocyanates was reacted with an equimolar mixture of the other reactants. The product mixtures were tested as inhibitors of acetylcholinesterase and their activities were used as indices to the rows and columns of a two-dimensional matrix reflecting the activities of individual products. An identical approach was used by the same authors in the preparation of a library of 72 tetrahydro-acridines by the condensation of 12 cyclohexanones with six cyanoanilines in 18 sublibraries [4]. [Pg.51]

The CBO matrix reflects the promoted, valence state of AO in the molecule, with the diagonal elements measuring the effective electron occupations of the basis functions, yiii = Ni = Npi. The AO-probability vector in this state, p = pi = Ni/N], groups the probabilities of the basis functions being occupied in the molecule. [Pg.6]

The screeners are interposed as a shield between the radiation and the polymer. They function either (a) by absorbing the radiation before it reaches the photoactive species in the polymer or (b) by limiting the damaging radiation penetration into the polymer matrix. Reflection of radiation can be achieved by selection of suitable paints, coatings, pigments or by metallizing [94, 95] the surface. [Pg.187]

Figure 5.9. (a) Geometry of a grain boundary normal to the plane of the foil and parallel to the direction m of the incident electron beam. The boundary has a periodicity along the direction p, and the boundary normal is specified by n. (b) The reciprocal lattice and Ewald sphere in the neighborhood of a matrix reflection, showing the extra reflections due to the periodic boundary and the streaking of the reflections in the direction n. (After Carter and Sass 1981.)... [Pg.144]

When the estimation procedure is clearly specified, an approximate covariance matrix of the estimate, Sj, can also be calculated. This matrix reflects the degree of precision of the estimate, and depends on the experimental design, parameters, and the noise statistics. A well-designed experiment with small random fluctuations will lead to precise estimations ( small covariance), while a small number of iminformative data and/or a high level of noise will produce unreliable estimates ( large covariance). [Pg.2948]

To see the dynamical characteristics of the present system, we first look at the (absolute) frequencies of structural transitions as well, which is tabulated in Table II. Let na be the number of transitions from a basin a to another basin b during a given running time. Nothing very special is found in this table except that it looks almost a symmetric matrix reflecting the microscopic reversibility [26],... [Pg.36]

When the estimation procedure is clearly specified, an approximate covariance matrix of the estimate, Sj, can also be calculated. This matrix reflects the degree... [Pg.267]

There is a straightforward relation between lu or ul transitions and concentration shifts. If we denote lu transition for the fth species with respect to change in the inflow of the yth species by + and the opposite transition by —, then we obtain a matrix equal to AXsymb. provided that the dependence of concentration of each species on any constraint is monotonous along the upper and lower branch [9], While the concentration shift matrix reflects local sensitivity of the steady state with respect to constraints, the bifurcation diagram is global in nature. This implies that any two columns of AXgymb determined from the lu/ul transitions are either the same or opposite, and the corresponding tilt is... [Pg.145]

Fig. 2.9 Schematic depiction of a carrier trajectory in a polymeric matrix reflecting the geometrical (off-diagonal) disorder. The electric field acts along the D-A direction v jump rate. Adapted from Bassler et al. [21] with permission from Wiley-VCH. Fig. 2.9 Schematic depiction of a carrier trajectory in a polymeric matrix reflecting the geometrical (off-diagonal) disorder. The electric field acts along the D-A direction v jump rate. Adapted from Bassler et al. [21] with permission from Wiley-VCH.
Table 1.6 Principal component (PC) analysis of descriptors of chemical structures for a set of diverse organic compounds (a) > 80% of the explained variance is expressed in the first four PCs (b) the loadings of the original descriptor variables in the VARIMAX rotated factor matrix reflect the grouping of the parameters (i.e. high loadings in the same PC indicate high intercorrelations between the descriptors). Table 1.6 Principal component (PC) analysis of descriptors of chemical structures for a set of diverse organic compounds (a) > 80% of the explained variance is expressed in the first four PCs (b) the loadings of the original descriptor variables in the VARIMAX rotated factor matrix reflect the grouping of the parameters (i.e. high loadings in the same PC indicate high intercorrelations between the descriptors).
The mechanism responsible for osteoporosis resulting from immobilization is not clear. One theory suggests that muscular activity stimulates osteoblastic activity in the bone. Another theory proposes that the rate of bone destruction is accelerated in osteoporosis. In immobilized innervated rat limb, there is an increased destruction in the matrix, reflected by a more rapid turnover of [ " C]glycine into the soft tissue. The increased turnover of amino acids into the protein of soft tissue is paralelled by an increased turnover by the calcium in the bone and the in the chondroitin sulfate. [Pg.356]

At the level of the first order density matrix all these states are indistinguishable. From this then follows that on using the first order similarity index (102), part of the structural information is inherently lost. The natural way how this inherent loss of information can be remedied consists in the use of second order, or pair density matrices. This is due to the fact that owing to partial inclusion of electron correlation, the pair density matrix reflects the difference in the electron structure of individual electron states of biradical species. [Pg.97]

This is an example of matrix multiplication of vectors. Just as before, the number of columns on the left (one) equals the number of rows on the right. Now, however, the number of elements in the vectors may differ, and the dimensions of the matrix reflect the dimensions of the original vectors. [Pg.311]

Instead of building separate quality models for each standard and level of criticality level, we build views on a global quality model for different levels of criticality by simply adjusting the requirements accordingly. This way, we note a set of requirements on the quality matrix reflecting specific recommendations for instance EN50128 (SIL 1-2) view. [Pg.126]

Positron annihilation lifetime spectroscopy (PALS) is a more recent tool used to probe free volume and free volume distribution in polymers (38, 59). PALS uses orthoPositronium (oPs) as a probe of free volume in the polymer matrix. oPs resides in regions of reduced electron density, such as free volume elements between and along chains and at chain ends (38). The lifetime of oPs in a polymer matrix reflects the mean size of free volume elements accessible to oPs. The intensity of oPs annihilations in a polymer sample reflects the concentration of accessible free volume elements. The oPs lifetime in a polymer sample is finite (on the order of several nanoseconds), so PALS probes the availability of free volume elements on nanosecond timescales (40). The minimum free volume cavity diameter required by oPs for localization is 3.SA (41), which is equal to the kinetic diameter of methane (42). Thus, PALS probes the dynamic availability of free volume elements similar in size to those important for gas separations applications. Several recent studies demonstrate the strong correlation of PALS parameters and transport properties in polymers (34, 38, 43-45). The chapter by Yampol skii and Shantarovich in this book describes the use of PALS to characterize free volume distribution in membrane polymers. [Pg.10]

The company s logistics customer service is determined by the weighting of the performance of the four factors lead time, delivery reliability, quality and flexibility according to their importance. The fiizzy comparison matrix reflects the judgment of the interviewees. The values of a and p are both assumed to be 0.5. After applying Eq. (5-3) and (5-4) the frizzy comparison matrix can be transferred to the second part shown in Eq. (5-8) from which eigenvalues and one eigenvector are derived. [Pg.77]


See other pages where Reflection matrix is mentioned: [Pg.699]    [Pg.159]    [Pg.319]    [Pg.66]    [Pg.406]    [Pg.382]    [Pg.178]    [Pg.100]    [Pg.106]    [Pg.699]    [Pg.58]    [Pg.334]    [Pg.113]    [Pg.36]    [Pg.64]    [Pg.64]    [Pg.492]    [Pg.311]    [Pg.136]   
See also in sourсe #XX -- [ Pg.97 , Pg.99 ]

See also in sourсe #XX -- [ Pg.214 ]




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Rotation-reflection transformation matrices

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