The dispersion of quantum-well resonances in ultrathin epitaxial Al films on Si(111) reveals energy- and wave vector-dependent reflection properties at the Al/Si interface. The substrate electronic structure strongly influences the phase shift of the electron waves upon reflection at the interface. Thus the details of the substrate electronic structure need to be taken into account for a comple...

We report on a 50 ks observation of the bright Seyfert 1 galaxy MCG−6-30-15 with the Rossi X-ray Timing Explorer. The data clearly show the broad fluorescent iron line (equivalent width ∼ 250 eV), and the Compton reflection continuum at higher energies. A comparison of the iron line and the reflection continuum has enabled us to constrain reflective fraction and the elemental abundances in the ...

For synthesizing realistic images of a real three dimensional object, reflectance properties of the object surface, as well as the object shape, need to be measured. This paper describes one approach to create a three dimensional object model with physically correct reflectance properties by observing a real object. The approach consists of three steps. First, a sequence of range images and col...

In concert hall acoustics, the reflection characteristics of the ceiling and the walls are important for minimizing the interaural cross correlation. Many design methods have been presented so far in order to design highly diffusing surfaces. This paper presents a two-dimensional digital waveguide mesh having a highly diffusing boundary using quadratic residue sequences, and illustrates its ref...

Preliminary results from an X-ray spectral study of Seyfert 1 galaxies with ASCA and RXTE are presented. From an analysis of X-ray reprocessing features of Compton reflection and Fe Kα fluorescence, it is found that iron line strength is not necessarily a good predictor of the amount of reflection. The variability properties of Fe Kα and reflection do not necessarily scale together and substant...

In the area of shape recognition tremendous advances were made during recent years. But in contrast to this success the recognition of materials is still a big challenge although for humans the identification of differnt materials is normally an easy task. In Computer Graphics we face a similar situation. While the modeling of shapes is already a highlydeveloped area the realistic modeling of t...

To accurately determine sample optical properties using single fiber reflectance spectroscopy (SFR), an absolute calibration of the reflectance is required. We investigated two SFR calibration methods, using a calibrated mirror and using the Fresnel reflection at the fiber tip as a reference. We compared these to commonly used calibration methods, using either Intralipid-20% in combination with...

We study polynomials which satisfy the same recurrence relation as the Szegő polynomials, however, with the restriction that the (reflection) coefficients in the recurrence are larger than one in modulus. Para-orthogonal polynomials that follow from these Szegő polynomials are also considered. With positive values for the reflection coefficients, zeros of the Szegő polynomials, para-orthogonal ...