We investigated limits on the human visual system's ability to discount directional variation in complex lights field when estimating Lambertian surface color. Directional variation in the light field was represented in the frequency domain using spherical harmonics. The bidirectional reflectance distribution function of a Lambertian surface acts as a low-pass filter on directional variation in...

We give a simple lower bound for the dimensions of the families of polynomially constructible spherical codes of given minimal angle ~o, deduced from the analog of the Katsman-Tsfasman-Vl~du!i bound for linear codes. In particulax the supremum rpol of the numbers log 2 CardX/dim X, where X ranges over all polynomially constructible families of spherical codes with ~ _> Ir/3, is such th~.t rpot ...

This paper describes an approach of representing 3D shape by using a set of invariant Spherical Harmonic (SH) coefficients after conformal mapping. Specifically, a genus-zero 3D mesh object is first conformally mapped onto the unit sphere by using a modified discrete conformal mapping, where the modification is based on Möbius Factorization and is aimed at obtaining a canonical conformal mappin...

The attainable specimen resolution is determined by the instrumental resolution limit d(i) and by radiation damage. Solid objects such as metals are primarily damaged by atom displacement resulting from knock-on collisions of the incident electrons with the atomic nuclei. The instrumental resolution improves appreciably by means of aberration correction. To achieve atomic resolution at voltages...

the electrical conductivity of the earth is its physical parameter, which can be studied in global scales. the investigations of the earth's electrical conductivity are based on geomagnetic field variations. time variations of the geomagnetic field consist of long-term and short-term (transient) variations. external sources induce electric currents into the earth. the induced electric curr...

A green low-cost and reproducible yeast mediated synthesis of silver nanoparticles is reported. The synthesis is performed at room temperature. X-ray and transmission electron microscopy analyses are performed to ascertain the formation of Ag nanoparticles. Nanoparticles almost spherical in shape having a size of 6-20 nm are found.

BACKGROUND In the active shape model framework, principal component analysis (PCA) based statistical shape models (SSMs) are widely employed to incorporate high-level a priori shape knowledge of the structure to be segmented to achieve robustness. A crucial component of building SSMs is to establish shape correspondence between all training shapes, which is a very challenging task, especially i...

Two disordered models are considered: spherical model and non-interacting electron gas on lattice. The supersymmetry representation for correlation functions of these models is obtained. Using this representation the conngura-tional averaging can be performed before thermodynamical one and the problem of calculation of conngurationally averaged correlation functions of disordered spherical mode...