Water is a vital resource for life as well as for the majority of energy industries. Finding a way to manage this water sustainably is essential at a time when the world's water resources are already under increasing stress due to population growth and global warming. As a direct implication, saving water is coming very crucial. This work deals with the application of the empirical mode decomposition method to the detection and the localization of the leaks using acoustic signals issued from STM32F4 acquisition card. Firstly, the empirical mode decomposition method has been applied in the denoising of acquired signals leading to two estimated components on which we apply secondly the correlation method to detect and localize the leakage in water distribution network. Experimental obtained results using a developed hydraulic plant as well as the acquisition system confirm the efficiency of the proposed method to detect accurately the leaks compared to conventional leaks detection methods.

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The use of invasive weeds optimization in the synthesis of antenna arrays has become popular in the last few years. This optimization method is robust, simple and can be easily improved. Like other stochastic algorithms, IWO suffers from premature convergence and other drawbacks. To overcome these problems, a dynamic IWO is proposed and used for synthesizing two antenna array topologies (linear and circular array). This proposed method tries to achieve an optimal array pattern by acting on the amplitude excitation of elements in the nonuniform circular array and their positions on the array, to obtain an array pattern with deep nulls in some directions of interferences and low side lobe level. For the linear array, the nulls control can be achieved by acting on the relative amplitude excitation of each element in the array for an optimal inter-element spacing. This proposed method improves the performance greatly and allows to achieve a maximum reduction in side lobe level in band Nulls with an acceptable dynamic range ratio (DRR). To show the performance of the proposed method, for each topology, our results are compared to other results of the literature.

Effects of a superstrate layer on the resonant frequency and bandwidth of a high Tc superconducting (HTS) circular printed patch are investigated in this paper. For that, a rigorous full-wave spectral analysis of superconducting patch in multilayer configuration is described. In such an approach, the spectral dyadic Green's function which relates the tangential electric field and currents at various conductor planes should be determined. Integral equations are solved by a Galerkin's moment method procedure, and the complex resonance frequencies are studied with basis functions involving Chebyshev polynomials in conjunction with the complex resistive boundary condition. To include the superconductivity of the disc, its complex surface impedance is determined by using London's equation and the model of Gorter and Casimir. Numerical results are compared with experimental results of literature as well as with the most recent published calculations using different methods. A very good agreement is obtained. Finally, superstrate loading effects are presented and discussed showing interesting enhancement on the resonant characteristics of the superconducting antenna using combinations of Chebyshev polynomials as set of basis functions.