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91.
Nour El Houda Hissi Bouchra Mokhtari Noureddine Cherkaoui Eddeqaqi Mohammed Musa Shabat Jacques Atangana 《Journal of Modern Optics》2013,60(16):1552-1557
A new ferrite slab made of a metamaterial (MTM), surrounded by a nonlinear cover cladding and a ferrite substrate, was shown to support unusual types of electromagnetic surface waves. We impose the boundary conditions to derive the dispersion relation and others necessary to formulate the proposed structure. We analyse the dispersion properties of the nonlinear surface waves and we calculate the associated propagation index and the film–cover interface nonlinearity. In the calculation, several sets of the permeability of the MTM are considered. Results show that the waves behaviour depends on the values of the permeability of the MTM, the thickness of the waveguide and the film–cover interface nonlinearity. It is also shown that the use of the singular solutions to the electric field equation allows to identify several new properties of surface waves which do not exist in conventional waveguide. 相似文献
92.
The localisation of devices that generate periodically activated hot spots in a CMOS IC comprising five metal layers and metal fills is addressed. The feasibility of using the phase shift of the displacement of the uppermost metal layer due to thermal expansions is demonstrated. 相似文献
93.
We focus on one critical issue in mobile ad hoc networks that is multicast routing. Advantages and limitations of existing routing protocols are illustrated. Optimal routes, stable links, power conservation, loop freedom, and reduced channel overhead are the main features to be addressed in a more efficient mechanism. In this paper, we propose a new on-demand multicast routing protocol, named Source Routing-based Multicast Protocol (SRMP). Our proposition addresses two important issues in solving routing problems: (i) path availability concept, and (ii) higher battery life paths. SRMP applies a source routing mechanism, and constructs a mesh to connect group members. It provides stable paths based on links' availability according to future prediction of links' states, and higher battery life paths. This protocol succeeded to minimize network load via designing optimal routes that guarantee reliable transmission and active adaptability. A performance comparison study with On-demand Multicast Routing Protocol (ODMRP) and Adaptive Demand-driven Multicast Routing (ADMR) protocol is undertaken. Analysis results show the strength of the SRMP nodes' selection criteria and its efficient energy consumption compared to the other two protocols. 相似文献
94.
95.
Abdoulkader Ali Mohamed Slim Salhi Souhir Abid Rachid El Gharbi Alain Fradet 《应用聚合物科学杂志》2014,131(15)
A series of random polyesteramides (PEAs) based on ε‐caprolactone and glycine were synthesized by a direct melt polycondensation method. Their structure was fully characterized by NMR spectroscopy. High molar mass PEAs were obtained for glycine contents lower than 15 mol‐%. The resulting copolymers are semi‐crystalline and present increasing glass transition temperatures but decreasing melting points at increasing glycine contents. Some of these PEAs exhibit better thermal stability and higher Young's modulus and ultimate tensile strength than PCL homopolymer. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40573. 相似文献
96.
Houda Ben Lajnef Houda Mejri Anouer Feriani Sheyma Khemiri Ezzeddine Saadaoui Nizar Nasri Nizar Tlili 《Journal of the American Oil Chemists' Society》2015,92(7):1043-1050
The goal of this study is to evaluate the chemical composition of the Prosopis farcta seeds. The Kjeldahl method revealed that the level of the total protein was ca. 18 % on a dry weight basis (DW). Gas chromatographic analysis revealed the presence of six fatty acids. Linoleic acid with 57.55 % was the major fatty acid, followed by oleic and palmitic acids (24.58 and 12.91 %, respectively). Total phenolic content was 1.71 mg GAE/g DW (GAE = gallic acid equivalents). Methanolic extracts showed important antioxidant properties. This work highlights the importance of P. farcta seeds as natural and inexpensive sources of protein, unsaturated fatty acid, and phenolic compounds for both cosmetic and pharmaceutical uses. 相似文献
97.
98.
Alireza Kazemipour Martin Hudlička Robert Dickhoff Mohammed Salhi Thomas Kleine-Ostmann Thorsten Schrader 《Journal of Infrared, Millimeter and Terahertz Waves》2014,35(9):720-731
Rising progress of mm-wave technology in spectroscopy, remote-sensing and its prospective application in communications requires accurate radiation beam characterization in quasi-optical systems. Gaussian approximation is a well-known practical model at optical and infrared wavelengths, and here we try to show the performance and limits of this method for the horn antenna as a classical mm-wave radiation source. This approach provides a compact and more practical analytical tool to design and optimize quasi-optical systems, compared to electromagnetic (EM) full-wave solutions. The radiation pattern (beam shape) and the phase distribution are studied analytically, both with the EM full-wave method and Gaussian approximation. Comparative results with measurements are presented to verify the analytical process and show the feasibility of the method for conventional horns. 相似文献
99.
J.M. Rampnoux H. Michel M.A. Salhi S. Grauby W. Claeys S. Dilhaire 《Microelectronics Reliability》2006,46(9-11):1520-1524
We propose in this paper a new backside imaging technique. Due to the constant increase ofnumerous metal layers, active areas can no longer be characterized through the frontside component. Nowadays, the most advanced imaging and failure analysis techniques require a modified backside component to allow probing. We propose a technique, where sample preparations are minimized. An optical time gating is used to reduce artefacts coming from the backside surface. 相似文献
100.
Stéphane Grauby Luis-David Patino Lopez Amine Salhi Etienne Puyoo Jean-Michel Rampnoux Wilfrid Claeys Stefan Dilhaire 《Microelectronics Journal》2009,40(9):1367-1372
We have studied the electrically induced off-plane surface displacement on two microelectronic devices using scanning Joule expansion microscopy (SJEM). We present the experimental method and surface displacement results. We show that they can be successfully compared with surface displacement images obtained using an optical interferometry method. We also present thermal images using scanning thermal microscopy (SThM) technique to underline that SJEM is more adapted to higher frequency measurements. The performances of the three methods are compared. 相似文献