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Simulating the Turbulent Hydrothermal Behavior of Oil/MWCNT Nanofluid in a Solar Channel Heat Exchanger Equipped with Vortex Generators

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Computer Modeling in Engineering & Sciences 2021年第3期126卷 855-889页

作者： Rachid Maouedj Younes Menni Mustafa Inc Yu-Ming Chu houari am.ur Giulio Lorenzini Unite de Recherche en Energies Renouvelables en Milieu Saharien URERMSCentre de Developpement des Energies RenouvelablesCDERAdrar01000Algeria Department of Physics Unit of Research on Materials and Renewable EnergiesFaculty of SciencesAbou Bekr Belkaid UniversityTlemcen13000Algeria Department of Mathematics Science FacultyFirat UniversityElazig23119Turkey Department of Medical Research China Medical University HospitalChina Medical UniversityTaichung40402Taiwan Department of Mathematics Huzhou UniversityHuzhou313000China Hunan Provincial Key Laboratory of Mathematical Modeling and Analysis in Engineering Changsha University of Science&TechnologyChangsha410114China Department of Technology University Centre of NaamaNaama45000Algeria Department of Engineering and Architecture University of ParmaParco Area delle Scienze 181/AParma43124Italy

Re-engineering the channel heat exchangers(CHEs)is the goal of many recent studies,due to their great importance in the scope of energy transport in various industrial and environmental *** the internal geometry of the CHEs by using extended surfaces,i.e.,VGs(vortex generators),is the most common technique to enhance the efficiency of heat *** work aims to develop a newdesign of solar collectors to improve the overall energy *** study presents a new channel design by introducing *** FVM(finite volume method)was adopted as a numerical technique to solve the problem,with the use of Oil/MWCNT(oil/multi-walled carbon nano-tubes)nanofluid to raise the thermal conductivity of the flow *** study is achieved for a Re number ranging from12×10^(3) to 27×10^(3),while the concentration(φ)of solid particles in the fluid(Oil)is set to 4%.The computational results showed that the hydrothermal characteristics depend strongly on the flow patterns with the presence of VGs within the *** the Oil/MWCNT rates with the presence of VGs generates negative turbulent velocities with high amounts,which promotes the good agitation of nanofluid particles,resulting in enhanced great transfer rates.

关键词： Channel heat exchanger forced-convection Oil/MWCNT nanofluid CFD vortex generators

Additive potential of ginger starch on antifungal potency of honey against Candida albicans

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Asian Pacific Journal of Tropical Biomedicine 2012年第4期2卷 253-255页

作者： Ahmed Moussa Djebli Noureddine Hammoudi SM Aissat Saad Akila Bourabeh Hemida houari Laboratory of Hygiene and Animal Pathology Institute of Veterinary Sciences University Ibn-KhadounTiaret Departments of Biology Faculty of SciencesMostaganem University Institute of Veterinary Sciences University Ibn-Khadoun Tiaret

Objective:To evaluate the additive action of ginger starch on the antifungal activity of honey against Candida albicans(***).Methods:*** was used to determine the minimum inhibitory concentration(MIC)of four varieties of Algerian *** concentrations of honey than the MIC were incubated with a set of concentrations of starch and then added to media to detennine the minimum additive inhibitory concentration(MAIC).Results:The MIC for the four varieties of honey without starch against *** ranged between 38%and 42%(v/v).When starch was incubated with honey and then added to media,a MIC drop was noticed with each *** of the four varieties ranged between 32%honey(v/v)with 4%starch and 36%honey(v/v) with 2%***:The use of ginger starch allows honey benefit and will constitute an alternative way against the resistance to antifungal agents.

关键词： Honey Ginger starch Antifungal potency Candida albicans

Floods and Hydrograms of Floods of Rivers in Arid Zones of the Mediterranean, Case of the Kingdom of Morocco

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International Journal of Geosciences 2020年第10期11卷 651-666页

作者： Boutoutaou Djamel Zeggane houari Belagoune Fares Department of Applicated Science Laboratory for the Exploitation and Development of Natural Resources in Arid Zones Ouargla University Ouargla Algeria

The Moroccan territory is often exposed to brutal and destructive floods. The latter is triggered by intense rains and sudden duration (rain showers, thunderstorms). The human and material damage caused by these floods has always been very high. The violence of the flood (1000 m3/s) of Oued Ourika on Aug 17, 1995, killed 730 people. The material damage caused by torrential rain only for the years 2008 and 2009 on the road network (roads and civil engineering works) represents more than 2.9 billion dirhams. The development of flood protection studies requires the values of the instantaneous frequency flow of a certain probability and the corresponding flood hydrogram, generally, these values are not available in the watersheds studied. The objective of this study is to propose for the Moroccan territory a method of calculating flood flows and hydrographs of floods for stream and wadis ungauged for the benefit of engineers and planners for possible studies of flood protection. The proposed method is based on the delimitation of homogeneous regions of Moroccan territory (three homogeneous regions). The frequency analysis carried out for these three zones made it possible to identify the climatic parameters necessary to calculate the flood index and consequently the frequency floods. The proposed Galton type flood hydrograph includes three parameters namely the rise time, the shape parameter and the flood index. These latter parameters are easily calculated by the formulas proposed.

关键词： Floods Arid Watersheds Basins Hydrograph

On Metaheuristic Optimization Motivated by the Immune System

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Applied Mathematics 2014年第2期5卷 318-326页

作者： Mohammed Fathy Elettreby Elsayd Ahmed houari Boumedien Khenous Department of Mathematics Faculty of Science King Khalid University Abha KSA Department of Mathematics Faculty of Science King Khalid University Abha KSA Department of Mathematics Faculty of Science Mansoura University Mansoura Egypt Department of Mathematics Faculty of Science Mansoura University Mansoura Egypt

In this paper, we modify the general-purpose heuristic method called extremal optimization. We compare our results with the results of Boettcher and Percus [1]. Then, some multiobjective optimization problems are solv... 详细信息

关键词： Multiobjective Optimization Extremal Optimization Immunememory and Metaheuristic

Synchronization of Impulsive Real and Complex Van der Pol Oscillators

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Applied Mathematics 2015年第6期6卷 922-932页

作者： Ali Al-Qahtani houari B. Khenous Shaban Aly Department of Mathematics Faculty of Science King Khalid University Abha KSA Department of Mathematics Faculty of Science Al-Azhar University Assiut Egypt

Nonlinear systems involving impulse effects, appear as a natural description of observed evolution phenomena of several real world problems, for example, many biological phenomena involving thresholds, bursting rhythm models in medicine and biology, optimal control models in economics, population dynamics, etc., do exhibit impulsive effects. In a recent paper [1], both real and complex Van der Pol oscillators were introduced and shown to exhibit chaotic limit cycles and in [2] an active control and chaos synchronization was introduced. In this paper, impulsive synchronization for the real and complex Van der Pol oscillators is systematically investigated. We derive analytical expressions for impulsive control functions and show that the dynamics of error evolution is globally stable, by constructing appropriate Lyapunov functions. This means that, for a relatively large set of initial conditions, the differences between the master and slave systems vanish exponentially and synchronization is achieved. Numerical results are obtained to test the validity of the analytical expressions and illustrate the efficiency of these techniques for inducing chaos synchronization in our nonlinear oscillators.

关键词： Real and Complex Van der Pol Chaotic Systems Error Systems Impulsive Synchronization

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三相逆变器并联系统中环流抑制的研究

智慧电力 2018年第5期46卷 15-21页

作者：樊晨曦李海锋 AZEDDINE houari 王钢华南理工大学电力学院广东广州510640 法国南特大学综合理工学院法国南特44600

在三相逆变器并联系统中,由于环流的产生,使用传统PI控制具有一定的局限性。将模糊控制与PI控制相结合,通过模糊控制对PI控制器参数进行在线整定,并针对环流问题,增加了环流抑制环节。最后在MATLAB/Simulink仿真环境中搭建了2台三相逆... 详细信息

在三相逆变器并联系统中,由于环流的产生,使用传统PI控制具有一定的局限性。将模糊控制与PI控制相结合,通过模糊控制对PI控制器参数进行在线整定,并针对环流问题,增加了环流抑制环节。最后在MATLAB/Simulink仿真环境中搭建了2台三相逆变器并联系统,对无控制、传统PI控制和改进模糊PI控制的控制效果进行对比分析。仿真结果表明,所提控制方法对于逆变器并联系统中产生的环流有很好的抑制效果。

关键词：逆变器并联环流 PI控制模糊控制

<i>Ab Initio</i>Study of Structural and Electronic Properties of Barium Chalcogenide Alloys

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Materials Sciences and Applications 2012年第9期3卷 612-618页

作者： Mohammed ameri amina Touia houari Khachai Zoubir Mahdjoub Mohamed Zoheir Chekroun amel Slamani Department of Physics Faculty of Sciences University Djillali Liabes Sidi-Bel-Abbés Algeria Laboratory of Communication Networks Architecture and Multimedia Sidi-Bel-Abbès University Sidi-Bel-Abbès Algeria

First-principles calculations have been used to study the structural and electronic properties of BaS1–xSex ternary alloy using full-potential muffin-tin orbital’s (FP-LMTO) method within density functional theory (DFT). In this approach, the local-density approximation (LDA) and generalized gradient approximation (GGA) are used for the exchange-correlation (XC) potential. The effect of composition on lattice parameter, bulk modulus, band gap and effective mass was investigated. The deviations of the lattice constant from Vegard’s law and the bulk modulus from linear concentration depend- ence were observed for BaS1–xSex alloy. The microscopic origins of bowing parameter were explained using approach of Zunger and co-workers. Accordance is found from the comparison of our results with other experimental and theo- retical calculations.

关键词： Semiconductor FP-LMTO Effective Mass

ameliorative Effects of <i>Syzygium aromaticum</i>Essential Oil on Fertility in Male Rats Exposed to Manganese

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Advances in Sexual Medicine 2013年第4期3卷 85-91页

作者： Farouk Boudou Abdelkrim Berroukche Malika Bendahmane-Salmi Badreddine Abdelkrim Kandouci Djallel Edinne houari adli Nasreddine Tou Department of Biology Faculty of Sciences and Technology Moulay Tahar University of Saida Saida Algeria Department of Biology Faculty of Sciences Djillali Liabes University of Sidi-Bel-Abbes Sidi-Bel-Abbes Algeria Pathology Laboratory University Hospital Complex of Sidi-Bel-Abbes Sidi-Bel-Abbes Algeria Research Laboratory of Environment and Health (RLEH) Faculty of Medicine University Hospital Complex (UHC) of Sidi-Bel-Abbes Sidi-Bel-Abbes Algeria

Introduction: Several substances were likely to cause the decline in male fertility which could go up to the complete sterility. The aim of this study was to assess the effects of Syzygium aromaticum essential oil on fertility in male rats exposed to manganese. Materials and Methods: Twenty four male rats, 6 months old, were divided into 2 groups;12 rats in one group received, by oral route, a water containing manganese chloride tetrahydrate (MnCl2·4H2O) is at the dose of 4.79 mg·ml-1 for 12 weeks. The group of control male rats received a distilled water in the same conditions. After a period of experimentation, each group was divided into two subgroups of 6 rats which received daily, by intraperitoneal way, a 0.1 mg/kg body weight, of Syzygium aromaticum essential oil. Results: After a chronic exposure, microscopic examination of the testes showed degeneration of the seminiferous tubules and the gremlin cell. Seminal parameters indicated a decrease in the sperm levels (21.3 × 106 cells/ml) and a rise of morphological abnormalities (66.1%). However, intraperitoneal administration of essential oil extracted from the flower buds of Syzygium aromaticum, during 3 weeks, to the rats previously intoxicated with Mn, showed a significant rising of sperm concentration (61.2 × 106 cells/ml) and a reduction of morphological abnormalities (10.8%). These changes were associated with a significant regeneration of seminiferous tubules and interstitial cells. Conclusion: This study revealed an ameliorative effect of essential oil Syzygium aromaticum in testicular tissue and the sperm quality.

关键词： Fertility Sterility Manganese Essential Oil Syzygium aromaticum

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一种改进的永磁电机无差拍预测控制方法

微电机 2017年第9期50卷 70-74页

作者：周露刘刚 A.houari 郭亚勋华南理工大学电力学院广州510641 IREENA Universite de Nnates

为解决数字控制方式固有的延时和开关非线性问题,提升电流环性能,本文基于永磁同步电机离散化数学模型,提出一种同时引入延时补偿和死区补偿改进无差拍电流预测的控制方法。在一个周期内,实现双步计算来补偿延时作用,并考虑逆变器开关... 详细信息

为解决数字控制方式固有的延时和开关非线性问题,提升电流环性能,本文基于永磁同步电机离散化数学模型,提出一种同时引入延时补偿和死区补偿改进无差拍电流预测的控制方法。在一个周期内,实现双步计算来补偿延时作用,并考虑逆变器开关的非线性及死区时间引起该周期内电压的变化进行电压补偿。相较于基本的预测方法,改进方法能够有效地提升动态响应和稳态精度,降低参数敏感性。

关键词：永磁同步电机无差拍电流控制延时补偿电压补偿