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Operators component projection

The matrix formed from the product of vectors, P = u (u ), is called a vector outer product. The expansion of a matrix in terms of these outer products is called the spectral resolution of the matrix. The matrix P satisfies the relation pkpt pk (Jq matrices of the more general form, P = X] P , where the summation is over an arbitrary subset of outer product matrices constructed from orthonormal vectors. Matrices that satisfy the relation P = P are called projection operators or projection matrices If P is a projection matrix, then (1 - P) is also a projection matrix. Projection matrices operate on arbitrary vectors, measure the components within a subspace (e.g. spanned by the vectors u used to define the projection matrix) and result in a vector within this subspace. [Pg.73]

In Eq. (56) or Eq. (57), no quasi-open or closed operators can project on to Xh since they have no inactive excitations in them, being labeled by active lines only. Hence, they do not appear in Eq. (56) or Eq. (57) for the Q-projection. Eq. (57) defines all the open components of Top, for every pu. By an entirely similar reasoning, we project all the quasi-open components of both sides of Eq. (55) for each /a and equate them (as the sufficiency conditions for defining Tq-opY... [Pg.608]

A lifetime extension project, responsible for the theoretical research and experiments that evaluates component condition and component capacity to continue operating. This project also defines the preventive and curative maintenance actions and proposes operating improvements. This project is run by experts from CEA, EDF and Framatome-ANP ... [Pg.84]

Because the operator G t) = is unitary, or norm preserving, the vector e A can be regarded as varying in time in such a way that its length (or norm) is preserved. The time evolution of A(t) is thus represented by a rotation in Liouville space. The scalar product of A (t) and A (0) gives the time correlation function Caa (0, and leads to the interpretation of Caa (0 as the component (or projection) of A (f) on A (0). An operator that projects an arbitrary vector onto A is... [Pg.238]

With the formation of the quinol product, QH2, the Q/QHj exchange can occur. As a result of the operation of this Q-cycle four H are pumped across the bacterial plasma membrane from the cytosol to the periplasm per electron pair transferred from Q to soluble cytochrome c. The resulting proton gradient drives the FoPj ATP-synthase-catalysed phosphorylation of ADP as in plant c-p/p and nc-p/p the H -con-ducting Fg component spans the bacterial plasma membrane and the ATP-synthase-containing F, component projects from it into the cytosol. [Pg.511]

This difficulty is overcome with the aid of a projection operator by projecting out from the Slater determinant the component with the desired multiplicity 25+1, annihilating all other contaminating components. This can be done either after an already performed calculation (spin projection after variation, UHF with annihilation), or, as Lowdin has pointed out, one would expect a more negative total energy if the variation is performed with an already spin-projected Slater determinant [spin projection before variation, spin-projected extended Hartree-Fock (EHF) method]. The reason is that a spin-projected Slater determinant is a given linear combination of different Slater determinants. The variation in the expectation value of the Hamiltonian formed with a spin-projected Sater determinant thus provides equations (EHF equations), whose solutions represent the solution of this particular multiconfigura-tional SCF problem. [Pg.29]

The "SIMON" Project ("On-line acoustic monitoring of structural integrity of critical power plant components operating at high temperatures") had a duration of 4 years (1.10.1993 -30.09.1997) the Project Consortium included CISE (Project Coordinator, I), MITSUI BABCOCK ENERGY (UK), HERIOT-WATT UNIVERSITY (IK), PROET / EDP (P) and ENEL (I). [Pg.71]

The question to be asked is Under what conditions (if at all) do the components of X fulfill Eq. (B.8) In [34] it is proved that this relation holds for any full Hilbert space. Here, we shall show that this relation holds also for the P sub-Hilbert space of dimension M, as defined by Eq. (10). To show that we employ, again, the Feshbach projection operator foraialism [79] [see Eqs. (11)]. [Pg.719]

We have to apply projection techniques which allow us to plot the hyperspaces onto two- or three-dimensional space. Principal Component Analysis (PCA) is a method that is fit for performing this task it is described in Section 9.4.4. PCA operates with latent variables, which are linear combinations of the original variables. [Pg.213]

Produced from a.tura.1 Ga.s, Cost assessments of methanol produced from natural gas have been performed (13—18). Projections depend on such factors as the estimated costs of the methanol production faciUty, the value of the feedstock, and operating, maintenance, and shipping costs. Estimates vary for each of these factors. Costs also depend on the value of oil. Oil price not only affects the value of natural gas, it also affects the costs of plant components, labor, and shipping. [Pg.423]

The cheat/server model oftea allows easier iategratioa with other aetwork apphcatioas (eg, fiaance, project management, or human resources) which typically operate ia the environment of the server component of the cheat/server system. Gheat/server can be gradually iatroduced ia an existing minicomputer environment, often with httie adverse incremental impact ia terms of retraining and additional cost. [Pg.521]

In general, the test object caimot be heated above its operating temperature in space. As free molecular conditions are obtained around the object, it outgases and, if solar-spectmm photons impinge on the object, increases the release of gas. Because the object is in a vessel and the area of the hole lea ding to the gas pump is small compared with the projected interior area of the vessel, molecules originating from the test object can return to the test object provided that they do not interact in some manner with the vessel walls and the other components of the molecular environment. The object inside the vessel estabhshes an entirely different system than the clean, dry, and empty vacuum vessel. The new system no longer has the capabiUty to reach the clean, dry, and empty base pressure within a reasonable time. [Pg.368]

QRA practitioners can use to satisfy some QRA objectives. Also, the American Institute of Chemical Engineers (AIChE) has sponsored a project to expand and improve the quality of component failure data for chemical industry use. And many process facilities have considerable equipment operating experience in maintenance files, operating logs, and the minds of operators and maintenance personnel. These data can be collected and combined with industrywide data to help achieve reasonable QRA objectives. However, care must be exercised to select data most representative of your specific system from the wide range available from various sources. Even data from your own plant may have to be modified (sometimes by a factor of 10 or more) to reflect your plant s current operating environment and maintenance practices. [Pg.10]

This chapter addresses project management aspects of a revamp. It also provides design guidelines that can be used by a refiner in selecting the revamp components. The original driving force for a project is often a particular mechanical problem or a process bottleneck. The ultimate objective of a revamp should be a safe, reliable, and profitable operation. [Pg.206]

The services of specialist personnel and plant mechanics will be required during this period to operate the equipment and carry out any day-to-day attention. Care should be taken that this work does not come into conflict with the recommendations of suppliers, or invalidate their warranties. Where major items have not yet been accepted from suppliers, it will be advisable to retain their own commissioning engineer or other attendant until the project is complete. All necessary maintenance must be carried out, since any premature failure of a component may be blamed on such an omission. [Pg.335]

As is clear from (7.38) and (7.32), the matrix of operator GA, which is of principal importance, is diagonal over the m-projections of the rotational moment. Owing to this, (7.38) separates into parts, which are not connected with each other. Each of them contains transitions with the same m-components of the initial rotational level and the same n-components of the final level. Substituting (7.37) into (7.29), one gets the following expression for the spectral contour ... [Pg.236]

We will now discuss an iterative scheme based on the CHF approach outlined in Sections 11 and 111, using the McWeeny procedure [7] for resolving matrices into components, by introducing projection operators R and R2, with respect to the subspaces spanned by occupied and virtual molecular orbitals. [Pg.284]

Hess, B.A. (1986) Relativistic electronic-structure calculations employing a two-component no-pair formalism with external-field projection operators. Physical Review A, 33, 3742-3748. [Pg.226]

The liquid desiccant cooling system is designed, built and installed. A series of problems occurred and caused a significant time delay. Due to that time delay the demonstration project has to be stopped and no reliable data of the component test and the system operation could have been recorded. [Pg.443]

Formally, each orthogonalized-plane-wave basis function may be written as (1 - P), where ijjk is a plane wave and P is the projection operator such that Pif/k gives the core-state component of Il>k ... [Pg.31]


See other pages where Operators component projection is mentioned: [Pg.204]    [Pg.12]    [Pg.122]    [Pg.264]    [Pg.70]    [Pg.35]    [Pg.257]    [Pg.2083]    [Pg.436]    [Pg.437]    [Pg.548]    [Pg.83]    [Pg.38]    [Pg.116]    [Pg.878]    [Pg.1]    [Pg.217]    [Pg.286]    [Pg.308]    [Pg.99]    [Pg.1]    [Pg.283]    [Pg.190]    [Pg.6]    [Pg.90]    [Pg.30]    [Pg.49]    [Pg.438]    [Pg.999]    [Pg.213]   
See also in sourсe #XX -- [ Pg.287 ]




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Component operational

Operator projection

Projection operations

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