We report the observation of nonlinear interactions in quadratic nonlinear crystals having a geometrically twisted susceptibility pattern. The quasi-angular-momentum of these crystals is imprinted on the interacting photons during the nonlinear process so that the total angular momentum is conserved. These crystals affect three basic physical quantities of the output photons: energy, translatio...

A program for computing pure angular momentum coefficients in relativistic atomic structure for any scalar one– and two–particle operator is presented. The program, written in Fortran 90/95 and based on techniques of second quantization, irreducible tensorial operators, quasispin and the theory of angular momentum, is intended to replace existing angular coefficient modules from GRASP92. The ne...

Text block segmentation is necessary in document layout analysis. An algorithm and its implementation that segregates text block by block (a block is either a title or a paragraph) from the provided document, e.g. newspaper image, based on pyramid structure is described in this paper. The pyramid structure, which is amenable for parallel processing on output, is a multi-resolution image represe...

Abstract In shipyards, blocks are controlled by connecting the crane and block with wires during erection. During lifting, if a is not carefully controlled, it will cause damage. Block lifting using operation performed controlling number of wires, hooks, equalizers. Consequently, predicting stable difficult. this study, we proposed control method to determine static equilibrium. Initially, an a...

We study the angular correlations of various galaxy catalogs (CfA1, SSRS1, Perseus-Pisces, APM Bright Galaxies and Zwicky). We find that the angular correlation exponent is γ a = 0.1 ± 0.1 rather than γ a = 0.7 as usually found by the standard correlation function ω(θ). We identify the problem in the artificial decay of ω(θ). Moreover we find that no characteristic angular scale is present in a...

Introduction. The well-ordered structures of block copolymer microdomains formed by self-assembly are potentially interesting optical materials, specifically as photonic crystals. Photonic crystals are structures with a periodic variation of refractive index.1-3 For light of the appropriate frequency, such crystals can be used to bend and steer the light, opening up many possible applications s...

Let $mathbf{c}_0$ be the real vector space of all real sequences which converge to zero. For every $x,yin mathbf{c}_0$, it is said that $y$ is block diagonal majorized by $x$ (written $yprec_b x$) if there exists a block diagonal row stochastic matrix $R$ such that $y=Rx$. In this paper we find the possible structure of linear functions $T:mathbf{c}_0rightarrow mathbf{c}_0$ preserving $prec_b$.

Can humans recover metric structure from motion sequences or, as has been claimed by Todd and Bressan [(1990) Perception & Psychophysics, 48, 419-430], are they limited to recovering only relief structure? Two experiments were carried out to investigate this question. In a metric-structure task, the angular thresholds for discriminating two rotating bi-planar structures were approximately 91 de...

background and aims. panoramic radiography is a method widely used because of low absorbed dose in patients (approximately 10 times less than that in the full mouth survey), reasonable cost and time. disadvantages of this radiography technique are magnification and distortion as a result of unequal magnification, which can influence dimensional and angular measurements used in clinical dentistr...

MZR(Multi-Zone Recording) disks are widely used for their high overall bandwidth and capacity nowadays. Since MZR disks show different bandwidths and capacities depending on the zone, data placement schemes for traditional CAD(Constant Angular Density) disks are not suitable for MZR disks. Especially, since the performance of continuous media servers strongly depend on the block placement schem...