We study the homogenization of an obstacle problem in a perforated domain, when the holes are periodically distributed and have random shape and size. The main assumption concerns the capacity of the holes which is assumed to be stationary ergodic.

3D ranging technologies generally fall into either position-based (triangulation) or time-based (LIDAR) approaches. Triangulation can provide much higher precision at close to mid-range but degrades quickly with the square of distance. LIDARs can provide reasonable precision over much longer distances but, unlike triangulation, they do not improve in capabilities at short range where precision ...

We apply boundary integral equations for the first time to the two-dimensional scattering of time-harmonic waves from a smooth obstacle embedded in a continuously-graded unbounded medium. In the case we solve, the square of the wavenumber (refractive index) varies linearly in one coordinate, i.e. (∆ + E + x2)u(x1, x2) = 0 where E is a constant; this models quantum particles of fixed energy in a...

We consider Pearson’s chi-square X2, the likelihood ratio G2, and Zelterman’s D2 as goodness-of-fit statistics for high energy physics problems in several dimensions, where the data are sparse. There is a fundamental obstacle in the “ultrasparse” case where all bins have at most one entry (ni = 0, 1 ∀i). A condition for avoiding this regime is derived; the allowed number of bins k rises faster ...

In this paper we present a new technique for improving the azimuth resolution of ultrasonic range sensors frequently used with mobile robots. This improvement is achieved without a significant increase in the latency, or processing delay, of the system. Our approach decreases the azimuth uncertainty of a sensor reading by eliminating portions of the reading that are contradicted by subsequent r...

Tsetse flies occur in 36 countries and a total area of about 10 million square kilometres in Africa. Throughout this area the disease transmitted by the tsetse fly, Trypanosomiasis (or Trypanosomosis), has a significant effect on large numbers of livestock. About 50 million cattle and tens of millions of small ruminants are considered to be at risk from Trypanosomiasis, and the disease is recog...

this article addresses an efficient and novel method for singularity-free path planning and obstacle avoidance of parallel manipulator based on neural networks. a modified 4-5-6-7 interpolating polynomial is used to plan a trajectory for a spherical parallel manipulator. the polynomial function which is smooth and continuous in displacement, velocity, acceleration and jerk is used to find a pat...

Due to several risks that involve travelling in highways, such as vehicle collision, natural disasters and other obstacles, the need of implementing an early warning system which detects obstacles to provide security has been growing in the last years. Artificial neural networks based systems have been successfully applied in obstacle detection through image processing and recognition. To addre...