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Geometry level

Geometry level at whieh the strueture is optimized higher-order eon-elation method(s) for estimating higher-order eorrelation effeets thermo level at which the thermodynamieal eoneetions are ealeulated [vibrational seale factor] MAD Mean Absolute Deviation for reference data set in kcal/mol. [Pg.167]

The lowest level of abstraction, here called the geometry level, is the closest to physical reality, in which the physics is described by partial differential equations. This level is the domain of finite-element, boundary-element or related methods (e.g., [7-9]). Due to their high accuracy, these methods are well suited for calculating, for example, the distribution of stresses, distortions and natural resonant frequencies of MEMS structures. But they also entail considerable computational effort. Thus, these methods are used to solve detailed problems only when needed, whereas simulations of complete sensor systems and, in particular, transient analyses are carried out using methods at higher levels of abstraction. [Pg.41]

Augmented with additional tight polarization functions Relativistic version of the cc-pVQZ basis Geometry = level at which the structure is optimized... [Pg.220]

By means of a suitable software it is quite possible to qualify each drilling. At first a geometry check examines whether the drillings are present and in that case if they are positioned correctly. Furthermore each hole is examined whether the reached temperature level lies within a given threshhold. A typical error is shown in illustration 7. In both filmcooling rows locked holes are to be recognized. [Pg.404]

By interpretation of the images obtained, one can check whether the digital radiograms can be compared to eonventional ones. To determine the detail perceptibility of this imaging system, an object with preliminary known geometry and with different levels of object contrast can be used. Exposures of such an object, under controlled conditions, enable the viewer to decide... [Pg.500]

For applications on indications it is assumed that the visibility level VL of rectangular objects (indications) is the same as for circles with the same area. The lenght 1 and width w of indications are correlated in very different manners, mainly dependant on the geometrie of the inhomogenity (crack). From some observations, the following correlation between w and 1 was introduced w (mm) = 0.05 + 0.03 1 (e g. 1=1.5 mm, w a 0.1 mm). For the same areas, the length 1 of the indication can be introduced in Fig. 1 as a second scale. [Pg.670]

Templates for each of the joint configurations are stored within the system. The operator selects one of the templates, and is provided with a visual representation, as shown in Figure 3, on which he can alter the Joint dimensions and weld geometry to match those of the item to be examined any ae-cess restrictions can also be defined. Using information from a database of available probes, along with the examination level required, ProcGen then calculates the set of scans required (see Figure 4). [Pg.767]

For this kind of case, a modification of the dilution method is being developed. Instead of using an external fixed-geometry measurement chamber, a suitable part of the process, e.g. a stretch of pipe, is used. A radiation detector is mounted on the outside of the pipe, and a tracer emitting sufficiently hard gamma radiation is used. As sufficient mixing can be achieved by injecting upstream the separator the radiation level found will be strictly proportional to the concentration and thus inversely proportional to the true flow rate. [Pg.1056]

Figure Bl.22.6. Raman spectra in the C-H stretching region from 2-butanol (left frame) and 2-butanethiol (right), each either as bulk liquid (top traces) or adsorbed on a rough silver electrode surface (bottom). An analysis of the relative intensities of the different vibrational modes led to tire proposed adsorption structures depicted in the corresponding panels [53], This example illustrates the usefiilness of Raman spectroscopy for the detennination of adsorption geometries, but also points to its main limitation, namely the need to use rough silver surfaces to achieve adequate signal-to-noise levels. Figure Bl.22.6. Raman spectra in the C-H stretching region from 2-butanol (left frame) and 2-butanethiol (right), each either as bulk liquid (top traces) or adsorbed on a rough silver electrode surface (bottom). An analysis of the relative intensities of the different vibrational modes led to tire proposed adsorption structures depicted in the corresponding panels [53], This example illustrates the usefiilness of Raman spectroscopy for the detennination of adsorption geometries, but also points to its main limitation, namely the need to use rough silver surfaces to achieve adequate signal-to-noise levels.
Figure Bl.22.10. Carbon K-edge near-edge x-ray absorption (NEXAFS) speetra as a fiinotion of photon ineidenee angle from a submonolayer of vinyl moieties adsorbed on Ni(lOO) (prepared by dosing 0.2 1 of ethylene on that surfaee at 180 K). Several eleetronie transitions are identified in these speetra, to both the pi (284 and 286 eV) and the sigma (>292 eV) imoeeupied levels of the moleeule. The relative variations in the intensities of those peaks with ineidenee angle ean be easily eonverted into adsorption geometry data the vinyl plane was found in this ease to be at a tilt angle of about 65° from the surfaee [71], Similar geometrieal detenninations using NEXAFS have been earried out for a number of simple adsorbate systems over the past few deeades. Figure Bl.22.10. Carbon K-edge near-edge x-ray absorption (NEXAFS) speetra as a fiinotion of photon ineidenee angle from a submonolayer of vinyl moieties adsorbed on Ni(lOO) (prepared by dosing 0.2 1 of ethylene on that surfaee at 180 K). Several eleetronie transitions are identified in these speetra, to both the pi (284 and 286 eV) and the sigma (>292 eV) imoeeupied levels of the moleeule. The relative variations in the intensities of those peaks with ineidenee angle ean be easily eonverted into adsorption geometry data the vinyl plane was found in this ease to be at a tilt angle of about 65° from the surfaee [71], Similar geometrieal detenninations using NEXAFS have been earried out for a number of simple adsorbate systems over the past few deeades.
Electronic structure theory describes the motions of the electrons and produces energy surfaces and wavefiinctions. The shapes and geometries of molecules, their electronic, vibrational and rotational energy levels, as well as the interactions of these states with electromagnetic fields lie within the realm of quantum stnicture theory. [Pg.2154]

For a very large number of variables, the question of storing the approximate Hessian or inverse Hessian F becomes important. Wavefunction optimization problems can have a very large number of variables, a million or more. Geometry optimization at the force field level can also have thousands of degrees of freedom. In these cases, the initial inverse Hessian is always taken to be diagonal or sparse, and it is best to store the... [Pg.2336]

The fonnation of surface aggregates of surfactants and adsorbed micelles is a challenging area of experimental research. A relatively recent summary has been edited by Shanna [51]. The details of how surfactants pack when aggregated on surfaces, with respect to the atomic level and with respect to mesoscale stmcture (geometry, shape etc.), are less well understood than for micelles free in solution. Various models have been considered for surface surfactant aggregates, but most of these models have been adopted without finn experimental support. [Pg.2599]

Four-level lasers offer a distinct advantage over tlieir tliree-level counterjiarts, (figure C2.15.5). The Nd YAG system is an excellent example of a four-level laser. Here tlie tenninal level for tlie laser transition, 2), is unoccupied tlius resulting in an inverted state as soon as any atom is pumped to state 3. Solid-state systems based on tliis pumping geometry dominate tlie marketplace for high-power laser devices. [Pg.2859]

Deep-level defects cannot be described by EMT or be viewed as simple perturbations to tlie perfect crystal. Instead, tlie full crystal-plus-defect problem must be solved and tlie geometries around tlie defect optimized to account for lattice relaxations and distortions. The study of deep levels is an area of active research. [Pg.2887]

The situation in singlet A electronic states of triatomic molecules with linear equilibrium geometry is presented in Figme 2. This vibronic structure can be interpreted in a completely analogous way as above for n species. Note that in A electronic states there is a single unique level for K =, but for each other K 0 series there are two levels with a unique character. [Pg.492]


See other pages where Geometry level is mentioned: [Pg.154]    [Pg.43]    [Pg.216]    [Pg.218]    [Pg.247]    [Pg.218]    [Pg.182]    [Pg.154]    [Pg.43]    [Pg.216]    [Pg.218]    [Pg.247]    [Pg.218]    [Pg.182]    [Pg.1138]    [Pg.1243]    [Pg.1253]    [Pg.1792]    [Pg.2222]    [Pg.2335]    [Pg.2341]    [Pg.2445]    [Pg.2445]    [Pg.2451]    [Pg.2749]    [Pg.301]    [Pg.442]    [Pg.477]    [Pg.482]    [Pg.493]    [Pg.500]    [Pg.501]    [Pg.501]    [Pg.501]    [Pg.507]    [Pg.508]    [Pg.509]    [Pg.535]   
See also in sourсe #XX -- [ Pg.41 ]




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Atomic-Level Geometry in Materials

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