In this paper, we propose an image encryption algorithm based on the chaos, substitution boxes, nonlinear transformation in galois field GF(2 8 ) and Latin square. Initially, the dynamic S-boxes are generated using Fisher-Yates shuffle method and piece-wise linear chaotic map. The algorithm utilizes advantages of keyed Latin square and affine-power-affine transformation to substitute highly cor...

Sensor Node Localization is considered to be one of the most critical issues in a Wireless Sensor Network (WSN). The objective of localization is determination of physical co-ordinates of a group of sensor nodes. The location information plays a vital role for coverage, deployment of sensor nodes and rescue operations. Many applications such as routing and target tracking are all location depen...

in which the front square is a pull-back. Then P is often called the fibre-product o f f and p, and it is also said that ~: P ~ X is induced by f from p. The map ~: Q~ P is determined by ~01 and q)2. Our object is to give conditions on the front and back squares which ensure that if q~l, q~2 and ~o are homotopy equivalences, then so also is ~. First of all we shall assume throughout that the ba...

In this paper we show how to embed the variable internal structure present in square implicit descriptions inside an (A, E, B) invariant subspace contained in the kernel of the output map. Thanks to this embedding, we make unobservable the variable internal structure, obtaining in this way a proper closed loop system with a controllable pre speciÞed structure. Copyright c ° 2002 IFAC.

A discrete analogue of the holomorphic map z γ is studied. It is given by Schramm's circle pattern with the combinatorics of the square grid. It is shown that the corresponding circle patterns are embedded and described by special separatrix solutions of discrete Painlevé equations. Global properties of these solutions, as well as of the discrete z γ , are established.

We have completed a 3 square degree CI 3P13P0 map of the ̊ Ophiuchi regions using SWAS. The remarkably stable receiver and backends systems of SWAS allow for uniformly calibrated data set on this scale. Combined with CO, CO, and 1̧8o maps made using FCRAO, this data set will facilitate a thorough study of the physics and the chemistry in this nearby star forming region.

We suggest an approach to grid optimization for a second order finite-difference scheme for elliptic equations. A model problem corresponding to the three-point finite-difference semidiscretization of the Laplace equation on a semi-infinite strip is considered. We relate the approximate boundary Neumann-to-Dirichlet map to a rational function and calculate steps of our finite-difference grid us...

Using the 850μm SCUBA camera on the JCMT and a scanning technique different from other sub-mm surveys, we have obtained a 125 square arcminute map centered on the Hubble Deep Field. The one-sigma sensitivity to point sources is roughly 3mJy and thus our map probes the brighter end of the sub-mm source counts. We find 6 sources with a flux greater than about 12mJy (> 4σ) and, after a careful acc...