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Communications in Computational Physics 2022年第5期31卷 1585-1635页

作者： Nadir-Alexandre Messaï Sebastien Pernet abdesselam bouguerra ONERA/DTIS Universitéfédérale de Toulouse F-31000 Toulouse France Laboratoire de Physique de la Matière et du Rayonnement(LPMR) Département de Sciences de la MatièreUniversitéde Souk-AhrasBP 155341000 Souk-AhrasAlgeria

This study aimed to specialise a directional H^(2)(DH^(2))compression to matrices arising from the discontinuous Galerkin(DG)discretisation of the hypersingular equation in acoustics.The significantfinding is an algorithm that takes a DG stiffness matrix andfinds a near-optimal DH^(2) approximation for low and high-frequency problems.We introduced the necessary special optimisations to make this algorithm more efficient in the case of a DG stiffness matrix.Moreover,an automatic parameter tuning strategy makes it easy to use and versatile.Numerical comparisons with a classical Boundary Element Method(BEM)show that a DG scheme combined with a DH^(2) gives better computational efficiency than a classical BEM in the case of high-order finite elements and hp heterogeneous meshes.The results indicate that DG is suitable for an auto-adaptive context in integral equations.

关键词： Integral equation boundary element method Helmholtz equation discontinuous Galerkin directional H^(2)-matrix low-rank approximation all frequency compression algorithm

Propagation of chirped solitons on a cw background in a non-Kerr quintic medium with self-steepening effect

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Communications in Theoretical Physics 2023年第12期75卷 3-11页

作者： abdesselam bouguerra Houria Triki Chun Wei Zhenbang Lu Qin Zhou Radiation and Matter Physics Laboratory Matter Sciences DepartmentMohamed-Cherif Messaadia UniversityP.O.Box 1553Souk-Ahras41000Algeria Radiation Physics Laboratory Department of PhysicsFaculty of SciencesBadji Mokhtar UniversityP.O.Box 1223000 AnnabaAlgeria School of Electronics and Information Engineering Wuhan Donghu UniversityWuhan 430212China School of Mathematical and Physical Sciences Wuhan Textile UniversityWuhan 430200China

We study the existence and stability of envelope solitons on a continuous-wave background in a non-Kerr quintic optical material exhibiting a self-steepening effect.Light propagation in such a nonlinear medium is governed by the Gerdjikov-Ivanov equation.We find that the system supports a variety of localized waveforms exhibiting an important frequency chirping property which makes them potentially useful in many practical applications to optical communication.This frequency chirp is found to be crucially dependent on the intensity of the wave and its amplitude can be controlled by a suitable choice of self-steepening parameter.The obtained nonlinearly chirped solitons include bright,gray and kink shapes.We also discuss the stability of the chirped solitons numerically under finite initial perturbations.The results show that the main character of chirped localized structures is not influenced by finite initial perturbations such as white noise.

关键词： solitons non-Kerr nonlinearity self-steepening effect

Nonlinear description of Yang-Mills cosmology： cosmic inflation and the accompanying Hannay's angle

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Chinese Physics C 2017年第6期41卷 115-121页

作者： Yacine bouguerra Mustapha Maamache Jeong Ryeol Choi Laboratoire de Physique Quantique et Systèmes Dynamiques Faculté des SciencesUniversite Ferhat Abbas Setif 1 Setif 19000 Algeria Département de Physique Facultédes Sciences Université de Jijel BP 98Ouled Aissa Jijel 18000 Algeria Department of Radiologic Technology Daegu Health College Yeongsong-ro 15 Buk-gu Daegu 41453 Republic of Korea

Hannay＇s angle is a classical analogue of the ＂geometrical phase factor＂ found by Berry in his research on the quantum adiabatic theorem. This classical analogue is defined if closed curves of constant action variables return to the same curves in phase space after an adaibatic evolution. Adiabatic evolution of Yang-Mills cosmology, which is described by a time-dependent quartic oscillator, is investigated. Phase properties of the Yang-Mills fields are analyzed and the corresponding Hannay＇s angle is derived from a rigorous evaluation. The obtained Hannay＇s angle shift is represented in terms of several observable parameters associated with such an angle shift. The time evolution of Hannay＇s angle in Yang-Mills cosmology is examined from an illustration plotted on the basis of numerical evaluation,and its physical nature is addressed. Hannay＇s angle, together with its quantum counterpart Berry＇s phase, plays a pivotal role in conceptual understanding of several cosmological problems and indeed can be used as a supplementary probe for cosmic inflation.

关键词： Yang-Mills cosmology Hannay angle time-dependent quartic Hamiltnian inflation

Boron Removal by Electrocoagulation Using Full Factorial Design

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Journal of Water Resource and Protection 2013年第9期5卷 867-875页

作者： Khaoula Missaoui Wided bouguerra Chiraz Hannachi Béchir Hamrouni UR11ES17 Traitement et Dessalement des Eaux Faculté des Sciences de Tunis Université de Tunis El Manar Tunis Tunisie

Saline waters treatment has become increasingly important for drinking water supply in a greater part of the world. However, some serious limitations had recently been discovered during water treatment, among them the boron problem seems to have a critical meaning. According to the WHO regulations (2011), the boron concentration should be reduced to less than 2.4 mg/L for drinking water. The purpose of this study is to investigate the feasibility of electrocoagulation (EC) as a pretreatment process to remove boron from saline waters. To optimize the experimental conditions of boron removal, the effects of some parameters were studied such as inter-electrode distance (die), electrode connection mode, (S/V) ratio, pHi and initial conductivity of the solution (σi). Subsequently, an experimental design methodology was implemented to evaluate statistically the most significant operating parameters. The effects of current density, EC time and initial boron concentration and their mutual interaction were investigated using 23 full factorial design. At optimal conditions, boron removal from synthetic aqueous solutions containing initial boron concentrations of 5 and 50 mg/L reached 81% and 79%, respectively. Applied to boron removal from seawater samples, EC reduces boron concentration to less to 2.4 mg/L with excessive energy consumption under optimal parameters.

关键词： Boron Removal Electrocoagulation Full Factorial Design

Adsorption of F-, NO3-and SO42-on AFN Anionic Membrane: Kinetics and Thermodynamics Studies

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American Journal of Analytical Chemistry 2013年第9期4卷 501-509页

作者： Chiraz Hannachi Fatma Guesmi Wided bouguerra Bèchir Hamrouni UR Traitement et Dessalement des Eaux Faculté des Sciences de Tunis Université de Tunis El Manar Manar II Tunisie

The sorption of and from aqueous solution on AFN membrane has been studied and the equilibrium isotherms determined. The experimental data have been analyzed using the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models at different temperatures varying from 283 to 313 K. The results were analyzed using three kinetic models, Lagergen first order, second order and the Elovich model. The obtained results show that the best-fit correlation of the experimental data was obtained using the second order model. Thermodynamic parameters for the adsorption system were determined at 283, 298 and 313 K.

关键词： AFN Membrane Adsorption Isotherm Kinetic Models Thermodynamics Parameters

Steel Electrodes Shape Influence on the Critical Field to Breakdown in Air–Application to High Voltage Safe Approach Distances Calculation

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Steel Electrodes Shape Influence on the Critical Field to Br...

Correlation between Dietary Intake and Inflammatory Biomarkers in a Tunisian Obese Group

2012 International Conference on Environmental and Materials Engineering(EME 2012)

作者： Salah Belkhir Toufik Ainouche Hocine Moulai Fathallah Soukeur Hacene bouguerra USTHB University of Science and Technology National Power Grid Manager (GRTE-SONELGAZ)

This investigation is consecrated to the influence of the shape and curvature radius of the made of steel electrodes on the maximal values of the applied electric field,enabling thus to establish a relation between the minimum approach distance and the shape of the tools used in the pertinent high voltage working area.The obtained results are of a great importance for accurately dimensioning the safety Minimum Approach Distances（MAD）for future live works that can be performed with non normalized tools.

关键词： Steel electrodes radius of curvature electric field live works safe approach distance

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Journal of Biosciences and Medicines 2015年第11期3卷 108-113页

作者： Manel Ayoub Chedia Zouaoui Nedra Grira Radhia Kochkar Nejla Stambouli Chaker bouguerra Borni Zidi Ezzedine Ghazouani Chakib Mazigh Zied Aouni Biochemistry Department Research Unit Military Hospital of Tunis Tunis Tunisia Endocrinology Department Research Unit Military Hospital of Tunis Tunis Tunisia Immunology Department Military Hospital of Tunis Tunis Tunisia Epidemiology Department Research Unit Military Hospital of Tunis Tunis Tunisia

Aims: This study aims to determine the inflammatory status and evaluate the correlation between dietary intake and inflammatory biomarkers in a Tunisian obese group. Material and Methods: This is an open cross-sectional study that includes 81 individuals divided into two groups: a group of 42 obese patients recruited from the endocrinology department and a control group of 39 non-obese healthy subjects. All participants received a food survey, anthropometric measurements and blood sampling. Pro-inflammatory cytokines (IL-6, IL-8, TNF-α), and hs-CRP were measured in patients and controls. Results: Dietary data revealed significant increases in food intake in obese patients compared to controls. The results of the laboratory parameters showed a statistically significant increase in IL-8, TNF-α and blood glucose in obese compared to controls. The analysis of correlations among the parameters studied showed that the plasma level of IL-6 was positively correlated with dietary fat intake (r = 0.70;p -3) and carbohydrate (r = 0.54;p = 0.03) and the dietary intake expressed in calories (r = 0.64;p -3). Conclusion: dietary imbalances in obese were observed and characterized by an excessive intake of calories, fat and carbohydrates. The excessive carbohydrate and fat intake is associated with increased IL-6 and TNF-α plasma levels.

关键词： Obesity Dietary Intake Inflammatory Biomarkers

Impact of glucotoxicity induced in vivoand in vitroin Psammomys obesus

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Journal of Diabetes Mellitus 2012年第1期2卷 59-71页

作者： Berdja Sihem Smail Leila Othmani Kheira Neggazi Samia Hamlat Nadjiba Boumaza Saliha Sahraoui Abdelhamid Kacimi Ghouti Haffaf El Mahdi Benazzoug Yasmina Aouichat bouguerra Souhila Laboratory of Cellular and Molécular Physiopathology Institute of Natural Sciences University of Technological Sciences Houari Boumediene Algiers Algeria

Objective: Chronic hyperglycemia characteristic of type diabetes 2 is responsible for the accelerated atherosclerosis with increased cardiovascular risk. In this study, we will propose to analyze the effect of a long-term of glucotoxicity in vivo in Psammomys obesus by addition of sucrose to 30% for 11 months and in vitro study of adventitial fibroblasts in the presence of D-glucose 0.6% for 7 days. Materials and methods: Evaluation of plasma biochemical parameters was carried out at the initial time and at the end of experiment. At autopsy, a morphological study of the aorta was performed after fixation in aqueous Bouin and staining with Masson’s trichrome. The experimental glucotoxicity is induced by incubation of fibroblasts in DMEM enriched with D-glucose at 0.6% for 7 days. The impact of glucotoxicity is assessed in the intracellular compartments through dosage of total nitrite and malondialdehyde, a product of lipid peroxidation, and thanks to a morphological assay after fixation of cells with aqueous bouin and blood staining with May Grünwald Giemsa. The evaluation of cell proliferation is accomplished by cell counting. Collagens I and III of the extracellular compartment are characterized by SDS-PAGE. Results: Animals subjected to sucrose showed hyperglycemia associated with hyperinsulinemia, dyslipidemia, hyperproteinemia, increased CPK and VLDL-LDL and decreased HDL. Histology of aortas revealed endothelial cells hypertrophy, severe disorganization of intima and media. In the presence of glucose, the proliferation of fibroblasts increases very significantly (P = 2.34 × 10-5), the rate of malonaldehyde, nitrite and total density of chains α2 (I) and α1 (I + III) extra-cellular collagens I and III increased significantly. After staining, the cells showed hypertrophy, vacuolation of cytoplasm and chromatin condensation with nuclear fragmentation, indicative of apoptosis. Conclusion: The glucotoxicity induced in vivo and in vitro is responsible for major structural and metabolic alterations leading to the a

关键词： Psammomys Obesus Aorta Adventitial Fibroblasts in Culture DT2 Glucotoxicity Extracellular Matrix Oxidative Stress

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五连败的中国麻将

中外管理 2014年第8期 31-31页

作者： Horiya bouguerra

中国缺的不是高人,而是将其引入职业化的机制与文化。“国粹”中国麻将,又输在了欧洲。7月7日,第五届欧洲麻将锦标赛在法国美丽的边境城市斯特拉斯堡落下帷幕。中国在这次比赛中只拿到个人最好成绩第30名、团体第37名的成绩!此役,中国... 详细信息

中国缺的不是高人,而是将其引入职业化的机制与文化。“国粹”中国麻将,又输在了欧洲。7月7日,第五届欧洲麻将锦标赛在法国美丽的边境城市斯特拉斯堡落下帷幕。中国在这次比赛中只拿到个人最好成绩第30名、团体第37名的成绩!此役,中国麻将军团兵败欧洲,受到中国国内,尤其是麻将爱好者的冷嘲热讽。

关键词：中国麻将斯特拉斯堡边境城市职业化欧洲锦标赛爱好者