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双随机调制技术及其功率谱密度特性分析

中国电机工程学报 2004年第4期24卷 97-101页

作者：王斌李兴源 K.el khamlichi DRISSI 三峡大学电气信息学院湖北宜昌443002 四川大学电力系四川成都610065 法国 Blaise Pascal 大学电气系

电力电子系统中,其开关运行方式对电磁兼容性会产生很大的影响。该文从硬开关技术的角度,提出的双随机调制技术能够有效地抑制和减小传导电磁干扰(EMI),而不需增加额外设备。应用统计通信原理,建立了双随机调制开关函数的功率谱密度理... 详细信息

电力电子系统中,其开关运行方式对电磁兼容性会产生很大的影响。该文从硬开关技术的角度,提出的双随机调制技术能够有效地抑制和减小传导电磁干扰(EMI),而不需增加额外设备。应用统计通信原理,建立了双随机调制开关函数的功率谱密度理论模型,实验结果表明了双随机调制技术比任何一种单随机调制具有更好的削减峰值和遣散功率谱的效果,从而有利于改善电力电子系统的电磁兼容性(EMC)。

关键词：电力电子系统运行方式双随机调制技术功率谱密度特性分析电磁兼容性

Geothermobarometry of Askaoun Pluton in Ouzellarh-Sirwa Promontory (Central Anti-Atlas;Morocco)

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Open Journal of Geology 2012年第3期2卷 136-147页

作者： abdeslam Toummite Moha Ikenne el Hassane Beraaouz Applied Geology and Environmental Geology Laboratory Faculty of Sciences Ibn Zohr University Agadir Morocco

Rocks of the late Neoproterozoic Askaoun pluton (558 ± 2 Ma) located in the Ouzellarh-Sirwa promontory (Anti-Atlas) include magmatic microgranular enclaves (MMEs) ranging from rounded to ovoid in shape, dark and fine grained and generally 5 to 10 cm in size, some reaching a size of 50 cm. They are composed of microdiorite, quartz microdiorite and micromonzodiorite, whereas the felsic host rocks comprise mainly quartz-diorite and amphibole-biotite granodiorite based on mineralogical compositions. The mineral assemblage is similar to those described in their hosting granitoids but with different proportions. In this study composition of minerals is used to describe the nature of the magma and estimate the pressure, temperature and oxygen fugacity at which Askaoun pluton is emplaced. Based on chemistry of biotite Askaoun pluton formed from calc-alkaline magma. Compositions of plagioclase (An5 - An29);hornblende (Mg ≠= 0.59 - 0.65) and biotite (Mg ≠= 0.49 - 0.55) of MMEs are slightly distinct or similar to those of host rocks (An7-40;hbl Mg ≠= 0.64 - 0.69;Bi Mg ≠= 0.49 - 0.50) which suggest partial to complete equilibration during mafic-felsic magma interaction. The coexisting hornblende and plagioclase (hornblende-plagioclase thermometry), Al content in hornblende (aluminum-in-hornblende barometry) and the assemblage titanite-magnetite-quartz were used to constrain the P, T and fO2 during the crystallization of the parent magmas. The Askaoun pluton was emplaced at temperature ca. 504°C - 633°C and at pressure ca. 0.9 - 4.66 ± 0.6 Kbars (average depth = 6.5 km) from a highly oxidized magma (log fO2 = ?24.8 to ?19.2).

关键词： Askaoun Pluton MMEs Hornblende Thermobarometry Ouzellargh-Sirwa Promontory Anti-Atlas Morocco

Removal of Methylene Blue from Water Using Hydroxyapatite Submitted to Microwave Irradiation

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Journal of Water Resource and Protection 2016年第3期8卷 358-371页

作者： Khadija Allam abdeslam el Bouari Bouchra Belhorma Lahcen Bih Laboratory of Physical Chemistry of Materials Applied Department of Chemistry Faculty of Sciences Ben M’sik University Hassan II Casablanca Casablanca Morocco National Centre for Energy Nuclear Science and Technology CNESTEN Rabat Morocco Group of Physico-Chemical of the Condensed Matter (PCMC) Faculty of Sciences Meknes University Moulay Ismail Meknès Morocco

This study investigated the power of hydroxyapatite adsorbent prepared by a combined precipitation-microwave method, for removing a cationic dye methylene blue in aqueous media. The used adsorbent was characterized by X-ray diffraction (XRD) and infrared spectroscopy (IR). The adsorption tests were conducted in batch mode. The effect of temperature, the pH of the solution and the mass of the adsorbent on the adsorption were determined. It is found that the adsorption was pH and temperature dependent. The kinetic study showed that the second-order model gives a better description of the kinetics of the adsorption reaction than the first-order model. Analysis of adsorption isotherms using different classical models showed that adsorption may be governed by the isotherms of Langmuir. The thermodynamic parameters were determined from the values of the maximum adsorption capacity and equilibrium constants.

关键词： Microwave Hydroxyapatite Methylene Blue Adsorption Kinetic Isotherms

A Finite element Approximation of the Stokes Equations

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World Journal of Mechanics 2011年第6期1卷 299-305页

作者： Samy Alami abdeslam elakkad Jawad el-Mekaoui Ahmed elkhalfi Mohammed el Hammoumi 不详

In this work, a numerical solution of the incompressible Stokes equations is proposed. The method suggested is based on an algorithm of discretization by the unstable of Q1 – P0 velocity/pressure ?nite element approximation. It is shown that the inf-sup stability constant is O(h) in two dimensions and O( h2) in three dimensions. The basic tool in the analysis is the method of modi?ed equations which is applied to ?nite difference representations of the underlying ?nite element equations. In order to evaluate the performance of the method, the numerical results are compared with some previously published works or with others coming from commercial code like Adina system.

关键词： Stokes Equations Finite element Method Iterative Solvers Adina System

A Novel Decoder Based on Parallel Genetic Algorithms for Linear Block Codes

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International Journal of Communications, Network and System Sciences 2013年第1期6卷 66-76页

作者： abdeslam Ahmadi Faissal el Bouanani Hussain Ben-Azza Youssef Benghabrit Department of Communication Networks National High School of Comptuer Science and System Analysis Rabat Morocco Department of Industrial and Production Engineering Moulay Ismail University National High School of Arts and Trades Meknès Morocco

Genetic algorithms offer very good performances for solving large optimization problems, especially in the domain of error-correcting codes. However, they have a major drawback related to the time complexity and memory occupation when running on a uniprocessor computer. This paper proposes a parallel decoder for linear block codes, using parallel genetic algorithms (PGA). The good performance and time complexity are confirmed by theoretical study and by simulations on BCH(63,30,14) codes over both AWGN and flat Rayleigh fading channels. The simulation results show that the coding gain between parallel and single genetic algorithm is about 0.7 dB at BER = 10﹣5 with only 4 processors.

关键词： Channel Coding Linear Block Codes Meta-Heuristics Parallel Genetic Algorithms Parallel Decoding Algorithms Time Complexity Flat Fading Channel AWGN

Geochemical assessment, mixing behavior and environmental impact of thermal waters in the Guelma geothermal system,Algeria

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Acta Geochimica 2019年第5期38卷 683-702页

作者： Foued Bouaicha Henia Dib Oualid Bouteraa Nabil Manchar Kamel Boufaa Nabil Chabour abdeslam Demdoum Department of Applied Biology Universite des Freres Mentouri Constantine 1025000 ConstantineAlgeria Department of Geology Universite des Freres Mentouri Constantine 1025000 ConstantineAlgeria Laboratory of Geology and Environment (LGE) Uni versite des Freres Mentouri Constantine 1ConstantineAlgeria Department of Geology Sciences University of Larbi Ben M'hidi04000 Oum El BouaghiAlgeria Department of Earth Sciences University of Setif 119000 SetifAlgeria

A study of thirteen geothermal springs located in the geothermal field of Guelma,northeastern Algeria,was *** were collected during the period between January 2014 and February *** processes responsible for the chemical composition of thermal and mineralized water were *** hydrochemical analysis shows that the thermal waters are characterized by the presence of two different chemical facies,the first type SO4-Ca in the east,west and south of Guelma,the second type HCO3-Ca in the *** analysis also attributed to sodium,chlorides,and sulfates to an evaporitic terrigenous origin by the molar ratio Sr2+/Ca2+.The thermal spring waters from Guelma geothermal system have a meteoric origin,and all samples are immature with strong mixing between hot and shallow waters with 19-38.5%rate of *** silica geothermometer shows that these thermal waters have a temperature varying from 84 to 122℃and that the water came from a depth of 2100-3000 m through a fault system that limits the pullapart basin of *** environmental effluent from thermal spas could pollute in both the irrigation and drinking waters,and which imposes danger on the health of the inhabitants of the region.

关键词： Geochemistry Geothermometry Mixing Thermal effluents Guelma Algeria

Towards an UML Profile for Web Service Composition Based on Behavioral Descriptions

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Journal of Software Engineering and Applications 2012年第9期5卷 711-721页

作者： Ayoub Sabraoui Ahmed Ettalbi Mohammed el Koutbi abdeslam En-Nouaary electrical and Computer Engineering Department Concordia University Montreal Canada Mobile Intelligent Systems Team (MIS) Ecole Nationale Supérieure d’Informatique et d’Nalyse des Systèmes (ENSIAS) Rabat Mo-rocco

Web service composition is one of the challenging issues that have been investigated over the past decade. It consists of combining and reusing existing Web services to best suit new user requirements. This paper proposes an UML profile to compose Web services based on their behavioral aspects. To do so, the web service WSDL files are first transformed to UML models;then the profile is used to integrate them;finally the MDA approach is adopted to transform the applied profile into a BPel process. As such, our method has the advantages of being independent of the Web service composition language and the UML modeling tool. Finally, a case study is developed in order to show the benefits of our method.

关键词： Web Service Composition UML Profile MDA BPel

Chemical Durability, Structure Properties and Bioactivity of Glasses 48P2O5-30CaO-(22−x)Na2O-xTiO2(With 0 <x ≤ 3;mol%)

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Advances in Materials Physics and Chemistry 2020年第12期10卷 305-318页

作者： Yassine Er-Rouissi Sara Aqdim abdeslam el Bouari Fouzia Hmimid Said Aqdim Faculty of Sciences Laboratory of Materials Engineering for Environment and Valorization Hassan II University Ain Chock Casablanca Morocco Faculty of Sciences Ben-M’sik Laboratory Physical-Chemistry of Applied Materials Hassan II University Casablanca Morocco Department of Biology Faculty of Science Laboratory Health & Environment Hassan II University Ain Chock Casablanca Morocco Department of Chemistry Faculty of Science Mineral Chemistry Laboratory Hassan II University Ain Chock Casablanca Morocco

Phosphate glasses of composition 48P2O5-30CaO-(22−x)Na2O-xTiO2 (with 0 °C ± 20°C. The chemical durability of these glasses shows an improvement when the TiO2 content varies from 0 to 2 mol%. The measurements of dif... 详细信息

Phosphate glasses of composition 48P2O5-30CaO-(22−x)Na2O-xTiO2 (with 0 elting at 1080°C ± 20°C. The chemical durability of these glasses shows an improvement when the TiO2 content varies from 0 to 2 mol%. The measurements of differential thermal analysis and density, both, indicate the increase of the glass transition temperature and the density. The increase of Tg leads to an improvement of glass rigidity. X-ray diffraction analysis of the glasses annealed at 650°C for 48 h, indicates the appearance of a mixture of metaphosphate and pyrophosphate phases when the TiO2 content varies from 0 to 2 mol%, the last become majority when the TiO2 content rich 2 mol%. Nevertheless, when the TiO2 content exceeds 2 mol%, the analysis, both, by infrared spectroscopy and X-ray diffraction, reveals a radical change of structure with the formation of majorities isolated orthophosphate groups. SEM micrographs illustrated that the number of crystallites increased in the glass network when the TiO2 content increased at the expense of the Na2

关键词： Chemical Durability Phosphate Glasses Titan Oxide Bioactivity SBF

Acute Hydrocephalus Revealing Unusual Cerebellar Mass: Dysplastic Cerebellar Gangliocytoma or Lhermitte-Duclos Disease (LDD)

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Neuroscience & Medicine 2013年第3期4卷 161-165页

作者： C.Karekezi M.Boutarbouch O.Coulibaly S.Derraz A.el Ouahabi A.el khamlichi Department of Neurosurgery Mohamed Vth UniversitySchool of MedicineCHU IBN SINAHopital des Spécialités ONORabatMorocco.

Lhermitte-Duclos disease (LDD) or dysplastic gangliocytoma of the cerebellum is a rare benign lesion of uncertain pathogenesis characterized by overgrowth of cerebellar ganglion cells which replace granular cells and Purkinje cells;this results in gross thickening of the cerebellar folia. It is revealed by symptoms of raised intracranial pressure, cerebellar impairment and obstructive hydrocephalus. We reported the case of a 41-year-old male who presented with symptoms of acute raised intracranial pressure. Brain computed tomography (CT) scan revealed hydrocephalus due to compression of the 4th ventricle by a large non-enhancing left cerebellar mass. Magnetic resonance imaging (MRI) showed a space-occupying lesion within the left cerebellar hemisphere with unusual striation. Radical surgery was retained though the margins with normal cerebellar tissue were not distinct. Clinical complications after gross total or partial removal of Lhermitte-Duclos lesions have been rarely reported in the literature;herein we stress the importance of extreme caution in removing these lesions in cerebellar areas that have no distinct margins between the lesion and normal tissue.

关键词： Lhermitte-Duclos Disease Dysplastic Gangliocytoma MRI Cerebellar Tiger Stripes