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Parametric structures

In contrast to a structure type (see Fixed structure type on page 25), at least one of the structure attribute types of a parametric structure type is a generic parameter. [Pg.31]


Li H, Watanabe K, Auslander D, Spear RC. 1994. Model parameter estimation and analysis Understanding parametric structure. Ann Biomed Eng 22 97-1 II. [Pg.68]

P. Ulrich, W. Scott, W.F. van Gunsteren and A. Torda, Protein structure prediction force 6elds parametrization with quasi Newtonian dynamics. Proteins 27 (1997), 367-384. [Pg.224]

Calculated transition structures may be very sensitive Lo the level of theory employed. Semi-empirical methods, since they are parametrized for energy miriimnm structures, may be less appropriate for transition state searching than ab initio methods are. Transition structures are norm ally characterized by weak partial" bonds, that is, being broken or formed. In these cases UHF calculations arc necessary, and sometimes even the inclusion of electron correlation effects. [Pg.17]

Because of the uncertainties related to the parametrization of an sp C, this approach is unsuitable for the study of protomeric equilibria for structures 4 through 8. We must lay stress on the fact that this simple treatment does not include (a) medium effects which are known to be important and b) the existence of associated species (see Chapter VII, Section I. LB) whose consequences have been thoroughly studied in pyridone series (1688). [Pg.5]

Structured uncertainty relates to parametric variations in the plant dynamics, i.e. uncertain variations in coefficients in plant differential equations. [Pg.303]

Semi-empirical methods may only be used for systems where parameters have been developed for all of their component atoms. In addition to this, semi-empirical models have a number of well-known limitations. Types of problems on which they do not perform well include hydrogen bonding, transition structures, molecules containing atoms for which they are poorly parametrized, and so on. We consider one such case in the following example, and the exercises will discuss others. [Pg.113]

Classification by objective Exploration Exploration OOOO well Appraisal well OO Delineation well Q New-structure test Q New-pool test Q Deeper-pool test Q Shallower-pool test Q New-licence block QQ appraisal test Fault block O extension test Appraisal/outpost 0 test (delineation) Stratigraphic test O0 New-field wildcat 0 New-pool wildcat 0 Deeper-pool test 0 Shallower-pool test 0 Outpost or 00 extension test Key well 00 - Group one - Group two Parametric well O0 Core well 00 Prospecting well 00 Exploratory well 00 Exploration O000 well Appraisal well 0O... [Pg.30]

After the somewhat tedious parametrization procedure presented above you are basically an expert in the basic chemistry of the reaction and the questions about the enzyme effect are formally straightforward. Now we only want to know how the enzyme changes the energetics of the solution EVB surface. Within the PDLD approximation we only need to evaluate the change in electrostatic energy associated with moving the different resonance structures from water to the protein-active site. [Pg.167]

There are two approaches for strueture optimization de-sign> parametric optimization and topology optimization. The parametric optimization aims at attaining the best set of geometric or structural parameters defining the configura-... [Pg.111]

Metrology - The goal of most metrology machine efforts is to keep the process under control, whether it involves making measurements of physical size of individual features and film thickness, or making electriccd measurements of parametric test structures. Defects are also measured and estimated, including excess particles and misplaced features in the composite. [Pg.328]

The minimization of this functional presents a problem which for many component mixtures can be quite timeconsuming if the truly optimal form of the interface and free energy is to be found. One may use an iterative method of solution much like the famous scheme used to solve for the Hartree-Fock wave function in electronic structure calculations [4]. An alternative, much to be preferred when sufficiently accurate, is to use a simple parametrized form for the particle densities through the interface and then determine the optimal values of these parameters. The simplest possible scheme is, of course, to take the profile to be a step function. [Pg.105]

H. van de Waterbeemd and B. Testa, The Parametrization of Lipophilicity and Other Structural Properties in Drug Research, Academic Press, London, 1987, pp. 85-225. [Pg.763]

The determination of the electronic structure of lanthanide-doped materials and the prediction of the optical properties are not trivial tasks. The standard ligand field models lack predictive power and undergoes parametric uncertainty at low symmetry, while customary computation methods, such as DFT, cannot be used in a routine manner for ligand field on lanthanide accounts. The ligand field density functional theory (LFDFT) algorithm23-30 consists of a customized conduct of nonempirical DFT calculations, extracting reliable parameters that can be used in further numeric experiments, relevant for the prediction in luminescent materials science.31 These series of parameters, which have to be determined in order to analyze the problem of two-open-shell 4f and 5d electrons in lanthanide materials, are as follows. [Pg.2]

A. Schiiurmann, G. COSMO a new approach to dielectric screening in solvents with explicit expressions for the screening energy and its gradient. J. Chem. Soc., Perkins Trans. 1993, 799-805. (c) Klamt, A. Jonas, V. Burger, T. Lohrenz, J. C. W. Refinement and parametrization of COSMO-RS. J. Phys. Chem. A 1998, 102, 5074—5085. (d) For a more comprehensive treatment of solvation models, see Cramer, C. J. Truhlar, D. G. Implicit solvation models equilibria, structure, spectra, and dynamics. Chem. Rev. 1999, 99, 2161— 2200. [Pg.65]


See other pages where Parametric structures is mentioned: [Pg.451]    [Pg.418]    [Pg.297]    [Pg.175]    [Pg.1702]    [Pg.32]    [Pg.33]    [Pg.71]    [Pg.290]    [Pg.31]    [Pg.451]    [Pg.418]    [Pg.297]    [Pg.175]    [Pg.1702]    [Pg.32]    [Pg.33]    [Pg.71]    [Pg.290]    [Pg.31]    [Pg.34]    [Pg.23]    [Pg.27]    [Pg.241]    [Pg.399]    [Pg.323]    [Pg.305]    [Pg.147]    [Pg.27]    [Pg.28]    [Pg.176]    [Pg.187]    [Pg.472]    [Pg.67]    [Pg.269]    [Pg.112]    [Pg.208]    [Pg.57]    [Pg.18]    [Pg.381]    [Pg.383]    [Pg.216]    [Pg.284]    [Pg.2]   


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