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One-matrix

A superlattice is temied commensurate when all matrix elements uij j are integers. If at least one matrix element uij j is an irrational number (not a ratio of integers), then the superlattice is temied incommensurate. A superlattice can be inconnnensiirate in one surface dimension, while commensurate in the other surface dimension, or it could be mconmiensurate in both surface dimensions. [Pg.1764]

This construction requires one matrix-vector multiplication with S and two inner products in each recursive step. Therefore, it is not necessary to store S explicitly as a matrix. The Lanczos process yields the approximation [21, 7, 12]... [Pg.430]

Designating the two veetors and one matrix just defined by boldfaee letters, the set of equations (2-44) is... [Pg.46]

MFI of the composition to that of the matrix, as a function of the filler concentration. It can be seen that, as the concentration of a particular filler increases, the index increases too for one matrix but decreases for another, and varies by a curve with an extremum for a third one. Even for one and the same polymerfiller system and a fixed concentration of filler, the stress-strain characteristics, such as ultimate stress, may, depending on the testing conditions (temperature, rate of deformation, etc.) be either higher or lower than in the reference polymer sample [36],... [Pg.7]

As we will soon see, the nature of the work makes it extremely convenient to organize our data into matrices. (If you are not familiar with data matrices, please see the explanation of matrices in Appendix A before continuing.) In particular, it is useful to organize the dependent and independent variables into separate matrices. In the case of spectroscopy, if we measure the absorbance spectra of a number of samples of known composition, we assemble all of these spectra into one matrix which we will call the absorbance matrix. We also assemble all of the concentration values for the sample s components into a separate matrix called the concentration matrix. For those who are keeping score, the absorbance matrix contains the independent variables (also known as the x-data or the x-block), and the concentration matrix contains the dependent variables (also called the y-data or the y-block). [Pg.7]

Proper evaluation of the necessary actions in solving problem (5) by the matrix elimination method is stipulated, as usual, by the special structures of the matrices involved. Because all the matrices are complete in spite of the fact that C is a tridiagonal matrix, O(iVf) arithmetic operations are required for determination of one matrix on the basis of all of which are known to us in advance. Thus, it is necessary to perform 0 Ni N2) operations in practical implementations with all the matrices j = 1,2,N-2- Further, 0 N ) arithmetic operations are required for determination of one vector with knowledge of and 0 Nf N2) operations for determination of all vectors Pj. [Pg.653]

C. Eckart and G. Young, The approximation of one matrix by another of lower rank. Psychometrika, 1 (1936)211-218. [Pg.158]

To demonstrate the validity of an analytical method, data regarding working range/ calibration, recovery, repeatability, specificity and LOQ have to be provided for each relevant sample matrix. Most often these data have to be collected from several studies, e.g., from several validation reports of the developer of the method, the independent laboratory validation or the confirmatory method trials. If the intended use of a pesticide is not restricted to one matrix type and if residues are transferred via feedstuffs to animals and finally to foodstuffs of animal origin, up to 30 sets of the quality parameters described above are necessary for each analyte of the residue definition. Table 2 can be used as a checklist to monitor the completeness of required data. [Pg.102]

Therefore, assigning all analyses of any one matrix to a single analytical laboratory is preferable to shifting the analyses among laboratories. [Pg.243]

The use of a matrix blank is the simplest way to overcome a matrix effect, but the analyst must ensure that the matrix blank is uniform and does not change between sample sets. Acquiring a uniform blank matrix may be problematic if assays are conducted over an extended time period. Caution must be taken when an analysis, validated for one matrix or species, is used for a different tissue or species, because... [Pg.684]

Figure 10.1 Schematic diagram of the sequential solution of model and sensitivity equations. The order is shown for a three parameter problem. Steps l, 5 and 9 involve iterative solution that requires a matrix inversion at each iteration of the fully implicit Euler s method. All other steps (i.e., the integration of the sensitivity equations) involve only one matrix multiplication each. Figure 10.1 Schematic diagram of the sequential solution of model and sensitivity equations. The order is shown for a three parameter problem. Steps l, 5 and 9 involve iterative solution that requires a matrix inversion at each iteration of the fully implicit Euler s method. All other steps (i.e., the integration of the sensitivity equations) involve only one matrix multiplication each.
The other species observed in irradiated Fe(CO)5-doped crystals of Cr(CO)6 also showed coupling to 57Fe, to a unique 13C, and to four other carbons. However, in this case g, AFe, and AC1 have only one matrix axis in common (that corresponding to the third component of each matrix listed in Table 4.10). [Pg.74]

Wolfbeis 1988 first dual sensor using one matrix (oxygen and C02)... [Pg.26]

Note that this kind of normalisation, via the norm function, can only be performed column- (or row-) wise via a loop as seen in the Matlab box above. Calling norm with one matrix argument determines a different kind of normalisation coefficients. We refer to the Matlab help and function references for more detail. [Pg.26]

This system of m equations can be written as one matrix equation. [Pg.113]

Actually, only one matrix need be stored if the adjacency matrix is stored initially and thereafter multiplied by itself. Matrix elements are replaced by the resulting product elements as they are computed. The product matrix obtained in this manner for the fcth power may contain some nonzero elements which correspond to paths longer than k steps instead of strictly k step paths, but this will not affect the final matrix obtained corresponding to the nth power, since these paths would eventually be identified in any case. All of the modifications to the methods of Section II mentioned above simplify the calculations needed to obtain the reachability matrix. The procedure for identifying the maximal loops given in Section II remains the same. [Pg.203]

All the variables are in the Laplace domain, as are all of the transfer functions. This set of N equations is very conveniently represented by one matrix equation. [Pg.549]

Although they did not obtain a closed-form analytic expression for the three-dimensional case, they dealt with a trasformed one-matrix for the single Slater determinant constructed from plane waves, and rewrote the energy in terms of this transformed matrix. The conditions on the transformation were not imposed through the Jacobian but rather through the equations ... [Pg.174]

Clearly then, the closed expression for the density-transformed 1-matrix in Eq. (52) (i.e., the 1-matrix constructed from transformed orbitals) is a function of the single-electron density p(r). Hence, when we express the total energy of an N-particle system (in the single-determinantal approximation) in terms of the transformed one-matrix described by Eq. (52), one can readily obtain an energy functional which depends on p. This fact, which has been exploited by several authors [59-62,85], is considered below with particular reference to the work of Ludeha [60]. [Pg.183]

The same type of procedure was applied to the Rh4(CO)i2 / HMn(CO)5 initiated homogeneous catalyzed hydroformylation of 3,3-dimethyl-l-butene at 298 K [94]. A set of e=21 experiments with k >26 spectra and v=4751 MIR spectral chaimels were used. The spectra from the 21 hydroformylation experiments were preconditioned and assembled into one matrix A7i3x295i- This data matrix was then... [Pg.182]

While all three matrices are interconvertible, the nonnegativity of the eigenvalues of one matrix does not imply the nonnegativity of the eigenvalues of the other matrices, and hence the restrictions Q>0 and > 0 provide two important 7/-representability conditions in addition to > 0. These conditions physically restrict the probability distributions for two particles, two holes, and one particle and one hole to be nonnegative with respect to all unitary transformations of the two-particle basis set. Collectively, the three restrictions are known as the 2-positivity conditions [17]. [Pg.25]

Another route to construction of the approximate 1-RDM functional involves employment of expressions for E and D afforded by some size-consistent formalism of electronic structure theory. Mazziotti [42] proposed a geminal functional theory (GET) where an antisymmetric two-particle function (geminal) serves as the fundamental parameter. The one-matrix-geminal relationship allowed him to define a D-based theory from GET [43]. He generalized Levy s constrained search to optimize the universal functionals with respect to 2-RDMs rather than wavefunctions. [Pg.392]

This decomposition of the 2-RDM is well known from the cumulant theory (see earlier chapters). F is the cumulant matrix of the 2-RDM. Since it arises from interactions in the Hamiltonian, it might also be called the pair correlation matrix. This definition of correlation differs from the traditional one since is the one-matrix of the correlated system and not that corresponding to independent particles. [Pg.406]

Afterward, we have to find approximations for 2-RDM spin components D". Let us now focus on high-spin cases only, such as doublet, triplet, quartet... spins for one, two, three. .. unpaired electrons outside the closed shells. Accordingly, singly occupied orbitals will always have the same spin (Al p = 0 or = 0) so the trace of the one-matrix, Eq. (6), becomes... [Pg.414]

ESR spectra in at least one matrix provide evidence for a localized ring-opened... [Pg.232]

The possible outcomes of measurements—combinations of scattering matrix elements—listed in Table 13.1 follow from multiplication of three matrices those representing the polarizer, the scattering medium, and the analyzer. If U is an element in the optical train, then the measured irradiance depends on only two matrix elements. In general, however, there are four elements in a combination, so that four measurements are required to obtain one matrix element. [Pg.416]

Membranes are semipermeable barriers that permit the separation of two compartments of different composition or even condition, with the transport of components from one compartment to another being controlled by the membrane barrier. Ideally, this barrier is designed to let pass selectively only certain target compounds, while retaining all others—hence the denotation semipermeable . Membrane separations are particularly suitable for food applications because (1) they do not require any extraction aids such as solvents, which avoids secondary contamination and, hence, the necessity for subsequent purification (2) transfer of components from one matrix to another is possible without direct contact and the risk of cross-contamination (3) membrane processes can, in general, be operated under smooth conditions and therefore maintaining in principle the properties and quality of delicate foodstuff. [Pg.427]


See other pages where One-matrix is mentioned: [Pg.702]    [Pg.701]    [Pg.302]    [Pg.92]    [Pg.39]    [Pg.277]    [Pg.285]    [Pg.140]    [Pg.948]    [Pg.81]    [Pg.73]    [Pg.85]    [Pg.181]    [Pg.184]    [Pg.398]    [Pg.409]    [Pg.64]    [Pg.98]    [Pg.135]    [Pg.66]    [Pg.111]    [Pg.103]   
See also in sourсe #XX -- [ Pg.253 ]




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Matrix Methods for the One-Dimensional Eigenvalue Schrodinger Equation

One-Electron Density Matrix Models

One-particle density matrices

One-particle reduced density matrix

Properties of the One-Particle Density Matrix

The one-electron density matrix

The one-step transition probability matrix

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