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Rigorous Electromagnetic Modeling of a Micro Strip Line Incorporating a Flat and Thick Metallic Conductor Based on the Skin Effect Phenomenon

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Open Journal of Metal 2022年第1期12卷 1-9页

作者： rafika Mejri Taoufik Aguili Communication System Laboratory Sys’Com National Engineering School of Tunis University Tunis El Manar Tunis Tunisia

In most studies of microstrip circuits, the majority of researchers assume that the microstrip structures studied have flat metallic conductors of finite widths but without thickness. But in reality these types of structures integrate metallic copper conductors of different thicknesses. If we neglect this thickness we introduce error in the electrical parameters of the microstrip structure, which affects the effective permittivity, the characteristic impedance, the adaptation of the circuit, the resonance frequency, etc. Given the importance of this parameter (thickness of the metal of micro rubon structures), rigorous electromagnetic modeling of the thick micro rubon line based on the skin effect phenomenon (In fact at high frequency the skin effect phenomenon occurs and the current only flows on the periphery of the conductor) has been proposed to improve the studied electric model and ensure the increase in the precision of the analysis method used: Wave concept iterative process. The good agreement between the simulated and published data justifies the improvement of the model.

关键词： Micro Strip Line Thick Conductor WCIP Skin Effect Phenomenon

New Formulation of the Mulilayer Iterative Method: Application to Coplanar Lines with Thick Conductor

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Journal of Electromagnetic Analysis and Applications 2016年第9期8卷 197-218页

作者： rafika Mejri Taoufik Aguili Communication System Laboratory Sys’Com National Engineering School of Tunis University of Tunis El Manar Tunis Tunisia

The skin effect is an electromagnetic phenomenon that makes the current flows only on the surface of the conductors at high frequency. This article is based on the phenomenon to model a structure made in coplanar technology. In reality, these types of structures integrated metal layers of different thickness of copper (9 μm, 18 μm, 35 μm, 70 μm). The neglect of this parameter introduces errors, sometimes significant, in the numerical calculations. This is why an iterative method (FWCIP) based on the wave concept was restated. Validation of results was carried out by comparison with those calculated by Ansoft HFSS software and Agilent ADS Technology. They show a good matching.

关键词： Skin Effect Electromagnetic Phenomenon Iterative Method Coplanar Structure Microwave

Modeling of Radiating Aperture Using the Iterative Method

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Detection 2022年第3期9卷 29-36页

作者： rafika Mejri Taoufik Aguili Communication System Laboratory Sys’Com National Engineering School of Tunis University Tunis El Manar Tunis Tunisia

We are interested in this work to electromagnetic leakage, for example the door of the microwave oven (or shielding of electronic functions working in the microwave band containing holes for ventilation circuit) which must be transparent (chain link) but the level of electromagnetic leakage issued by this device must not exceed certain standards. This work started with this article in which we are interested in a simple structure consisting of a multilayer structure incorporating a radiating aperture. We show in this paper mainly the interests of this study and the limitations of using these structures. Modeling of this device is provided by the wave concept iterative procedure (WCIP) which is simple to implement and is characterized by the fast execution method. The validation of our work is carried out by comparing our results with those calculated by the Ansoft HFSS software which shows a good agreement.

关键词： Electromagnetic Leakage Radiating Aperture Microwave Iterative Method Planar Structure Multilayer Electromagnetic Shielding

A New Approach Based on Iterative Method for the Characterization of a Micro-Strip Line with Thick Copper Conductor

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Journal of Electromagnetic Analysis and Applications 2016年第5期8卷 95-108页

作者： rafika Mejri Taoufik Aguili Communication System Laboratory Sys’Com National Engineering School of Tunis University Tunis El Manar Tunis Tunisia

In this work, we applied two electromagnetic models for the characterization of a planar structure including a flat, thick copper conductor. Indeed the first model is consisted by modeling two metal ribbons without bulkiness, placed one above the other at a distance of h2 equal to the thickness of the thick conductor. This approach has been implemented and tested by the iterative method. The results of simulations have been compared with those calculated by the Ansoft HFSS software, and they are in good concordance, validating the method of analysis used. The second model is based on the calculation of the effective permittivity of the medium containing the thick conductor. This medium consists of a metallic region of complex relative permittivity , the rest of this medium is filled with air er2 = 1. The effective permittivity eeff calculated from these two relative permittivity er2 and . Comparing the simulation results of this new formulation of the iterative method with those calculated by the software Ansoft HFSS shows that they are in good matching which validates the second model.

关键词： Thick Conductor Iterative Method Micro-Strip Line Microwaves Skin Effect Phenomenon Effective Permittivity

太阳能/地热联合有机朗肯循环电厂的能量和火用优化

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Journal of Central South University 2023年第11期30卷 3601-3616页

作者： rafika MAALI Tahar KHIR Müslüm ARICI University of Gabes National Engineering School of GabesResearch Laboratory of Applied ThermodynamicGabesLR18ES336029Tunisia Mechanical Engineering Department Engineering FacultyKocaeli UniversityKocaeli 41001Turkey

对突尼斯南部一个太阳能和地热能驱动的有机朗肯循环(ORC)电厂进行了能量和火用分析。分别研究了在冬季和夏季2天内主要运行参数对太阳能/地热联合ORC系统的影响,确定了系统的质量、能量和火用平衡。结果表明,系统不可逆性的主要来源是... 详细信息

对突尼斯南部一个太阳能和地热能驱动的有机朗肯循环(ORC)电厂进行了能量和火用分析。分别研究了在冬季和夏季2天内主要运行参数对太阳能/地热联合ORC系统的影响,确定了系统的质量、能量和火用平衡。结果表明,系统不可逆性的主要来源是抛物面通流收集器。为了减少火用损耗,优化系统性能,采用多项式回归分析方法进行优化。由此建立了传热流体的质量流量和入口温度与太阳辐射的关系。该优化方案可使系统的火用效率在冬季提高2.06%~5.44%,在夏季提高1.00%~4.10%。此外,分析显示,在冬季,总能源效率和净功率分别提高了26.6%和21.0%。

关键词：火用效率太阳能地热能优化有机朗肯循环

Iris Recognition Based on Multilevel Thresholding Technique and Modified Fuzzy c-Means Algorithm

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Journal on Artificial Intelligence 2022年第4期4卷 201-214页

作者： Slim Ben Chaabane rafika Harrabi Anas Bushnag Hassene Seddik Computer Engineering Department Faculty of Computers and Information TechnologyUniversity of TabukTabuk47512Saudi Arabia Department of Electrical Engineering University of TunisCEREPENSIT 5 AvTaha Hussein1008TunisTunisia

Biometrics represents the technology for measuring the characteristics of the human *** authentication currently allows for secure,easy,and fast access by recognizing a person based on facial,voice,and fingerprint *** authentication is one of the essential biometric methods for identifying a *** authentication type has become popular in research and practical *** the face and hands,the iris is an internal organ,protected and therefore less likely to be ***,the number of helpful information collected from the iris is much greater than the other biometric human *** work proposes a new iris identification model based on a multilevel thresholding technique and modified Fuzzy cmeans *** multilevel thresholding technique extracts the iris from its surroundings,such as specular reflections,eyelashes,pupils,and *** the other hand,the modified Fuzzy c-means is used to combine and classify the most useful statistical features to maximize the accuracy of the collected ***,having the most optimal iris *** proposed model results are validated using True Success Rate(TSR)and compared to other existing *** results show how effective the combination of the two stages of the proposed model is:the Otsu method and modified Fuzzy c-means for the 400 tested images representing 40 people.

关键词： Biometric authentication recognition iris recognition statistical features feature extraction fuzzy c-means TSR sensitivity classification

玉米根叶甲的为害与玉米的异羟肟酸含量和植株发育的关系

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园艺与种苗 1997年第1期 41-44页

作者：ＲａｆｉｋＡ．Ａｓａｂｇｕｉ

玉米根叶甲的为害与玉米的异羟肟酸含量和植株发育的关系ＲａｆｉｋＡ．Ａｓａｂｇｕｉ等玉米的生产和产量受病虫害限制。在北美洲造成最大经济损失的害虫之一就是玉米根叶甲（ＤｉａｂｒｏｔｉｃａｖｉｒｇｉｆｅｒａＬｅＣｏｎｔｅ）... 详细信息

玉米根叶甲的为害与玉米的异羟肟酸含量和植株发育的关系ＲａｆｉｋＡ．Ａｓａｂｇｕｉ等玉米的生产和产量受病虫害限制。在北美洲造成最大经济损失的害虫之一就是玉米根叶甲（ＤｉａｂｒｏｔｉｃａｖｉｒｇｉｆｅｒａＬｅＣｏｎｔｅ）（鞘翅目：叶甲科）。在美国由于害虫...

关键词：叶甲科自交系金花虫科品系(育种) 玉米根植株发育氧肟酸异羟肟酸

Indian Anti-Malaria OMARIA Is Effective Against African Drug Resistant <i>P. falciparum</i>Field Isolates and Laboratory Strains;without Toxicity

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International Journal of Clinical Medicine 2012年第1期3卷 1-8页

作者： Jean Bernard Lekana-Douki Deepak Bhattacharya rafika Zatra Fousseyni S. Toure-Ndouo 不详

OMARIA which is used to treat malaria in Odisa province, India, was investigated in Africa. The in-vitro anti-malarial activity of OMARIA was tested on P. falciparum strains FCB (chloroquine-resistant) and 3D7 (chloroquine-sensitive) and on fresh clinical isolates from Gabon, using the DELI method. Host cell toxicity was analysed with the MTT test. Interesting activity was observed. Inhibition concentrations (IC50) were 20.6 ± 5.2 μg/ml and 14.1 ± 4.3μg/ml respectively on FCB and 3D7 strains. On clinical isolates, the mean of IC50 was 10.65 ± 4.8μg/ml. OMARIA is highly potent against all field isolates tested by us (Gabon includes Pfmdr1 N86). Lethal dose on Vero cells being 165 ± 10.7μg/ml indicate a selective index of 13 for FCB, i.e., non-toxic. Data substantiates scientific rationale for use of OMARIA. This information and such understanding can be used in searching African phyto parables (for use in Africa with similar results as in India) and in new drug design. With Indian assistance, Punica granatum can also be cultivated in Central Africa, and OMARIA can be made, with an aim to Fight Malaria at Home.

关键词： Fruit Extracts OMARIA Antiplasmodial Activity Asia-Africa Efficacy Cytotoxicity Drug Resistant-Field Isolates Plasmodium Falciparum

Effect of the Ce Content on a Nuclear Waste Glassy Matrix in the System SiO2-Al2O3-CaO-MgO-ZrO2-TiO2, Synthesized at a Low Melting Temperature

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材料科学与工程（中英文A版） 2013年第4期3卷 209-223页

作者： Nour-el-Hayet Kamel Dalila Moudir Ziane Kamel Abdelmoumene Djerridi Samy Mouhamou AbdelbakiBenmounah rafika Souag Mustapha Taouinet Hamid Ait-Amar Department of Spectrometry Algiers Nuclear Research Centre Algiers Algeria Faculty of Sciences M'hamed Bougara University Boumerdes 35000 Algeria Metallurgy Department Draria Nuclear Research Centre Sebala Draria Algeria Faculty of Mechanical and Process Engineering El-Alia Houari Boumediene University of Science and Technology Bab-EzzouarAlgiers Algeria