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Transformation reconstructive

Fig. S-2. Activation energy both ibr reconstruction of the surface (100) plane of platinum crystals in vacuum and for im-reconstruction of the reconstructed surface due to adsorption of C 0 (1x1) (5x20) is surface lattice transformation (reconstruction and un-reconstruc-tion). 6 = adsorption coverage. [From Ertl, 1985.]... Fig. S-2. Activation energy both ibr reconstruction of the surface (100) plane of platinum crystals in vacuum and for im-reconstruction of the reconstructed surface due to adsorption of C 0 (1x1) (5x20) is surface lattice transformation (reconstruction and un-reconstruc-tion). 6 = adsorption coverage. [From Ertl, 1985.]...
Sato, S., 2011. Transformational Reconstruction. Center for Pattern Design, St. Helena, CA. [Pg.220]

A new one-dimensional mierowave imaging approaeh based on suecessive reeonstruetion of dielectrie interfaees is described. The reconstruction is obtained using the complex reflection coefficient data collected over some standard waveguide band. The problem is considered in terms of the optical path length to ensure better convergence of the iterative procedure. Then, the reverse coordinate transformation to the final profile is applied. The method is valid for highly contrasted discontinuous profiles and shows low sensitivity to the practical measurement error. Some numerical examples are presented. [Pg.127]

In the special case when a = 0 these measurements can be named as longitudinal, transversally longitudinal, and transverse measurement, respectively. These potentials can be reconstructed directly using the inverse Radon transform (5). [Pg.135]

Grangeat P. Mathematical framework of cone beam three-dimensional reconstruction via the first derivative of the Radon transform.. Math. Methods in Tomography, V.1947 of Springer Lecturre Notes in Math-cs, Springer-Verlag, Berlin, 1991, p.66-97. [Pg.220]

Typical tomographic 2D-reconstruction, like the filtered backprojection teelinique in Fan-Beam geometry, are based on the Radon transform and the Fourier slice theorem [6]. [Pg.494]

Another efficient and practical method for exact 3D-reconstruction is the Grangeat algorithm [11]. First the derivative of the three-dimensional Radon transfomi is computed from the Cone-Beam projections. Afterwards the 3D-Object is reconstructed from the derivative of the Radon transform. At present time this method is not available for spiral orbits, instead two perpendicular circular trajectories are suitable to meet the above sufficiency condition. [Pg.494]

A second disadvantage in the use of topological indices is that whereas the process of transformation of connectivity into one number is straightforward, the reverse process of reconstruction of connectivity from the index is not possible. [Pg.295]

The reconstruction Z of the transformed contingency table Z in a reduced space of latent vectors follows from ... [Pg.192]

For the purpose of comparison, we also discuss briefly the biplot constructed from the CFA using the exponents a = 0.5 and P = 0.5 (Fig. 32.10). Such a display is meant to reconstruct the values in the transformed contingency table Z by projections of points representing rows upon axes representing columns (or vice versa) ... [Pg.199]

Fig. 40.31. Data compression by a Fourier transform, (a) A spectrum measured at 512 wavelengths (b) spectrum after reconstruction with 2, 4,..., 256 Fourier coefficients. Fig. 40.31. Data compression by a Fourier transform, (a) A spectrum measured at 512 wavelengths (b) spectrum after reconstruction with 2, 4,..., 256 Fourier coefficients.
Hadamard transform [17], For example the IR spectrum (512 data points) shown in Fig. 40.31a is reconstructed by the first 2, 4, 8,. .. 256 Hadamard coefficients (Fig. 40.38). In analogy to spectrometers which directly measure in the Fourier domain, there are also spectrometers which directly measure in the Hadamard domain. Fourier and Hadamard spectrometers are called non-dispersive. The advantage of these spectrometers is that all radiation reaches the detector whereas in dispersive instruments (using a monochromator) radiation of a certain wavelength (and thus with a lower intensity) sequentially reaches the detector. [Pg.564]

Figure 5.10 STM images of a Cu(l 10)-O surface (a), after exposure (10 L) to CH3OH at 270 K (b) and 40 min later (c). Note the transformations of the (2 x 1)0 strings into zig-zag chains and c(2 x 2) structures (b) and with time the oxygen has been removed and the surface evolved into a (5 x 2) methoxy reconstruction (c). (Reproduced from Ref. 37). Figure 5.10 STM images of a Cu(l 10)-O surface (a), after exposure (10 L) to CH3OH at 270 K (b) and 40 min later (c). Note the transformations of the (2 x 1)0 strings into zig-zag chains and c(2 x 2) structures (b) and with time the oxygen has been removed and the surface evolved into a (5 x 2) methoxy reconstruction (c). (Reproduced from Ref. 37).
Of crucial significance in deciding between various models have been estimates of the number of copper atoms required to transform the surface into a (2 x 3)N phase. This was the approach adopted by Takehiro et al 2 in their study of NO dissociation at Cu(110). They concluded that by determining the stoichiometry of the (2 x 3)N phase that there is good evidence for a pseudo-(100) model, where a Cu(ll0) row penetrates into the surface layer per three [ll0]Cu surface rows. It is the formation of the five-coordinated N atoms that drives the reconstruction. The authors are of the view that their observations are inconsistent with the added-row model. The structure of the (2 x 3)N phase produced by implantation of nitrogen atoms appears to be identical with that formed by the dissociative chemisorption of nitric oxide. [Pg.142]

Fourier transformation to reconstruct the spin-density function of the sample, q(i). The variation of gradients is symbolized by diagonal lines in Figure 1.4. [Pg.11]

The joint density function for each voxel can be reconstructed by taking inverse Fourier transforms with respect to each of the wave vectors ... [Pg.370]

Using the valence profiles of the 10 measured directions per sample it is now possible to reconstruct as a first step the Ml three-dimensional momentum space density. According to the Fourier Bessel method [8] one starts with the calculation of the Fourier transform of the Compton profiles which is the reciprocal form factor B(z) in the direction of the scattering vector q. The Ml B(r) function is then expanded in terms of cubic lattice harmonics up to the 12th order, which is to take into account the first 6 terms in the series expansion. These expansion coefficients can be determined by a least square fit to the 10 experimental B(z) curves. Then the inverse Fourier transform of the expanded B(r) function corresponds to a series expansion of the momentum density, whose coefficients can be calculated from the coefficients of the B(r) expansion. [Pg.317]

After calculating the Fourier transform of the Compton profiles one observes that the amplitude of its oscillations becomes smaller than this statistical error when r is greater than 15 a.u. and therefore the B(r) function cannot be used for r > 15 a.u. On the other hand if one wants to get results for Cu with a similar statistical error compared to the results of the Li reconstruction the number of counts needed is given by... [Pg.318]


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