Ocean ambient noise is generated in many ways such as from winds, rain and shipping. A technique has recently been developed (Harrison and Simons, J. Acoust. Soc. Am, Vol. 112 no. 4, 2002) that uses the vertical directionality of ambient noise to determine seabed properties. It was shown that taking a ratio of upward looking beams to downward produces an estimate of the reflection loss. This te...

Optical properties of doped silicon wafers have been measured by means of terahertz time domain reflection spectroscopy. A method is proposed to obtain the relative phase by reflection accurately. By using this method, the relative phase is obtained within an error of less than 10 mrad at 1 THz. The experimentally obtained complex conductivity of relatively high-doped silicon (r 50.136 V cm) in...

The problem, whether every topological space has a weak compact reflection, was answered by M. Hušek in the negative. Assuming normality, M. Hušek fully characterized the spaces having a weak reflection in compact spaces as the spaces with the finite Wallman remainder. In this paper we prove that the assumption of normality may be omitted. On the other hand, we show that some covering propertie...

Iterative least-squares estimation requires acciirate reflectance models to retrieve geometrical pammeters of curved surface elements from an image projection. W e investigate the use of .separating the diffuse (body) reflection from the specular (surface) reflection being re8ponsible for image highlights. Experzments show that the (smooth) daffuse component yields the best convergence properti...

The Skorokhod oblique reflection problem is studied in the case of n-dimensional convex polyhedral domains. The natural sufficient condition on the reflection directions is found, which together with the Lipschitz condition on the coefficients gives the existence and uniqueness of the solution. The continuity of the corresponding solution mapping is established. This property enables one to con...

We use geometry of Davis complex of a Coxeter group to investigate finite index reflection subgroups of Coxeter groups. The main result is the following: if G is an infinite indecomposable Coxeter group and H ⊂ G is a finite index reflection subgroup then the rank of H is not less than the rank of G. This generalizes results of [7]. We also describe some properties of the nerves of the group an...

We derive an expression for the Casimir force between slabs with arbitrary dielectric properties characterized by their reflection coefficients. The formalism presented here is applicable to media with a local or a non-local dielectric response, an infinite or a finite width, inhomogeneous dissipative, etc. Our results reduce to the Lifshitz formula for the force between semi-infinite dielectri...

Detection of highlights is a prominent issue in computer vision, graphics and image processing. Applications which require object properties measurement or rendering are affected by specular reflection since the models assume matte diffusing surfaces most of the time. Hence, detection, and sometimes removal, of specular reflection (highlights) in an image may be critical. Several methods are pr...

Using reflection spectroscopy of optically pumped sodium vapor, we have performed what is to our knowledge the first direct measurement of the spatially inhomogeneous spin polarization near a glass surface. On the basis of a theoretical description of the reflection at an inhomogeneous, anisotropic medium, we deduce the magnitude of the small residual magnetization at the surface from an analys...

In this paper, we introduce baby Verma modules for symplectic reflection algebras of complex reflection groups at parameter t = 0 (the so–called rational Cherednik algebras at parameter t = 0) and present their most basic properties. As an example, we use baby Verma modules to answer several problems posed by Etingof and Ginzburg, [5], and give an elementary proof of a theorem of Finkelberg and...