geometrical structure, nuclear magnetic resonance (n1,1it) chemical shielding tensors, and chemical shiftsof silicon and carbon nucler are investigated for twn infinite size zigzag and armchair single-walled siliconcarbide nanotabes (sicnts). geometrical structures of sients, sit bonds and bond angles of st and cvertices in both zigzag and armchair nanotubes, indicate that bond lengths are appr...

We consider a numerical method based on the so-called “orthogonality condition” for the approximation and continuation of invariant tori under flows. The basic method was originally introduced by Moore [1], but that work contained no stability or consistency results. We show that the method is unconditionally stable and consistent in the special case of a periodic orbit. However, we also show t...

Equations are described to derive the true anterior chamber dimensions of an eye from a photograph of its optical section. If the surface of the eye is assumed to be spherical, the three-dimensional coordinates of rays emanating from the anterior chamber to a camera can be transformed to two-dimensional coordinates on a plane, which contains rays both inside and outside of the "eye." The actual...

3. Component separation: We compute the pure diffuse image component and the specular image component. We can easily appreciate the two main directions in the data. The most clear is the one corresponding to the diuse line Ld which rises from the coordinate system origin. The second, less dened, appearing at the end of the diffuse elongation, is the specular direction identied by the specular l...

Reconstruction in Cone-Beam Tomography can suffer from artifacts due to geometrical misalignments of the source-detector system. They can be avoided by a complete and precise description of the system. We present a high precision method for the geometric calibration for the PIXSCAN, a small animal X-ray CT scanner demonstrator based on hybrid pixel detectors (XPAD2). The specificities of the XP...

We develop a fast method for solving the one-dimensional wave equation based on geometrical optics. From geometrical optics (e.g., Fourier integral operator theory or WKB approximation) it is known that high-frequency waves split into forward and backward propagating parts, each propagating with the wave speed, with amplitude that is slowly changing depending on the medium coefficients, under t...