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Wave Reflection by Rectangular Breakwaters for Coastal Protection

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Fluid Dynamics & Materials Processing 2024年第3期20卷 579-593页

作者： Hasna Akarni hamza Mabchour Laila el Aarabi Soumia Mordane Laboratory of Polymer Physics Mechanical Sciences and MaterialsFaculty of Sciences Ben M’SikHassan II University of CasablancaCasablanca20670Morocco

In this study,we focus on the numerical modelling of the interaction between waves and submerged structures in the presence of a uniform flow *** the same and opposite senses of wave propagation are *** main objective is an understanding of the effect of the current and various geometrical parameters on the reflection *** wave used in the study is based on potential theory,and the submerged structures consist of two rectangular breakwaters positioned at a fixed distance from each other and attached to the bottom of a wave *** numerical modeling approach employed in this work relies on the Boundary element Method(BEM).The results are compared with experimental data to validate the *** findings of the study demonstrate that the double rectangular breakwater configuration exhibits superior wave attenuation abilities if compared to a single rectangular breakwater,particularly at low ***,the study reveals that wave mitigation is more pronounced when the current and wave propagation are coplanar,whereas it is less effective in the case of opposing current.

关键词： Wave current breakwaters Boundary element Method(BEM) reflection coefficient

Modulation of oxidative damage and genotoxicity of biosynthesized zinc oxide nanoparticles via supplementation with modified cinnamaldehyde-loaded chitosan nanoparticles in mice

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Food Science and Human Wellness 2024年

作者： Mosaad A.Abdel-Wahhab Aziza A.el-Nekeety Asmaa S.Salman Zeinab K.hamza Engy M.Akl Soher E.Aly Wenyi Kang Department of Food Toxicology & Contaminants， National Research Centre Dokki， Cairo， Egypt Genetic and Cytology Department， National Research Centre Dokki， Cairo， Egypt Department of Fats and Oils， National Research Centre Dokki， Cairo， Egypt National R & D Center for Edible Fungus Processing Technology， Henan University Joint International Research Laboratory of Food & Medicine Resource Function Functional Food Engineering Technology Research Center Henan

Synthesis of zinc oxide nanoparticles (Zn-NPs) via green method is an outstanding alternative to conventional/regular methods; however， the safety or toxicity of the biosynthesized ZnO-NPs in vivo is not fully explored. This study was conducted to evaluate the protective efficiency of cinnamaldehyde-loaded chitosan nanoparticles (Cin@CSNPs) against oxidative damage and genotoxicity of zinc oxide nanoparticles (ZnO-NPs) in mice. ZnO-NPs were biosynthesized using the extract of fresh leaves of Mentha pulegium L. Cin was extracted from cinnamon essential oil， and was loaded into chitosan nanoparticle (Cin@CSNPs). Both ZnO-NPs， Cin@CSNPs and CSNPs were characterized. The in vitro release of Cin@CSNPs was determined. In the biological study， 6 groups of male Balb/c mice were treated by gavage for 3 weeks as follows， control group， the group received ZnO-NPs (25 mg/kg b.w)， the groups received Cin@CSNPs at low dose (50 mg/kg b.w) or high dose (100 mg/kg b.w)， and the groups received ZnO-NPs plus Cin@CSNPs at the two tested doses. Blood and tissue samples were collected for different biochemical， genetical and histological studies. The particle size of ZnO-NPs， CSNPs， and Cin@CSNPs were (20.78 ± 2.6)， (170.0 ± 3.7)， and (218.23 ± 2.9) nm， and ξ-potential were (32.7 ± 4.6)， (8.32 ± 0.27) and (4.8 ± 0.21)， respectively. ZnO-NPs disturbed the biochemical and oxidative stress indices， AFP， CEA， TNF-α， chromosomal aberrations in somatic and germ cells， and sperm abnormality along with severe pathological changes in the hepatic， renal， and testicular tissues. Cin@CSNPs improved significantly all the parameters tested and the histological picture in a dose-dependent. Therefore， the biosynthesized ZnO-NPs exhibit oxidative damage and genotoxicity， and Cin@CSNPs have potential protective effects against the risks of ZnO-NPs and may be a promising tool to overcome the challenges of using Cin in food and pharmaceuticals applications.

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Optimization of energy exchange in microgrid networks: a coalition formation approach

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Protection and Control of Modern Power Systems 2019年第1期4卷 322-331页

作者： Chaimaa Essayeh Mohammed Raiss el Fenni hamza Dahmouni Department of Communication Systems INPTRabatMadinat Al IrfaneMorocco

In this paper, we elaborate a new strategy based on cooperative game theory models to encourage and manage the interactions in a MicroGrid network. The proposed strategy optimizes the cooperation and the energy exchange in a distributed μGrid network. The strategy consists of a two stage algorithm: Coalition formation algorithm which was specifically created to approximate the optimal set of coalitions that return considerable savings. And the Matching game to manage the energy exchange inside each coalition. The performance of our strategy was verified through simulations. These latter show that the losses can be considerably decreased by the use of the proposed strategy: the rate of the loss reduction can reach up to 20% if the two stages are applied on the network. Moreover, the strategy proved to have a fast convergence which makes it operational for real implemented networks.

关键词： MicroGrid network Energy optimization Cooperative Game theory Matching game Coalition formation

β-divergence loss for the kernel density estimation with bias reduced

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Statistical Theory and Related Fields 2021年第3期5卷 221-231页

作者： hamza Dhaker el Hadji Deme Youssou Ciss Mathematiques et statistique Universite de MonctonMonctonCanada UFR SAT Universite Gaston BergerSaint-LouisSenegal

In this paper,we investigate the problem of estimating the probability density *** kernel density estimation with bias reduced is nowadays a standard technique in explorative data analysis,there is still a big dispute on how to assess the quality of the estimate and which choice of bandwidth is *** framework examines the most important bandwidth selection methods for kernel density estimation in the context of with bias *** reference,least squares cross-validation,biased cross-validation andβ-divergence loss methods are described and expressions are *** order to assess the performance of our various bandwidth selectors,numerical simulations and environmental data are carried out.

关键词： bandwidth β-divergence nonparametric estimatio

First Insights into the Viral Communities of the Deep-sea Anoxic Brines of the Red Sea

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Genomics, Proteomics & Bioinformatics 2015年第5期13卷 304-309页

作者： Andr Antunes Intikhab Alam Marta Filipa Simoes Camille Daniels Ari J.S.Ferreira Rania Siam hamza el-Dorry Vladimir B.Bajic Computational Bioscience Research Center (CBRC) ComputerElectrical and Mathematical Sciences and Engineering Division (CEMSE)King Abdullah University of Science and Technology (KAUST) Red Sea Research Center (RSRC) Biological and Environmental Sciences and Engineering Division (BESE)King Abdullah University of Science and Technology (KAUST) Biology Department American University in Cairo

The deep-sea brines of the Red Sea include some of the most extreme and unique envi- ronments on Earth. They combine high salinities with increases in temperature, heavy metals, hydrostatic pressure, and anoxic conditions, creating unique settings for thriving populations of novel extremophiles. Despite a recent increase of studies focusing on these unusual biotopes, their viral communities remain unexplored. The current survey explores four metagenomic datasets obtained from different brine-seawater interface samples, focusing specifically on the diversity of their viral communities. Data analysis confirmed that the particle-attached viral communities present in the brine-seawater interfaces were diverse and generally dominated by Candovirales, yet appearing distinct from sample to sample. With a level of caution, we report the unexpected finding of Phycodnaviridae, which infects algae and plants, and trace amounts of insect-infecting Iridoviridae. Results from Kebrit Deep revealed stratification in the viral communities present in the interface： the upper-interface was enriched with viruses associated with typical marine bacteria, while the lower-interface was enriched with haloviruses and halophages. These results provide first insights into the unexplored viral communities present in deep-sea brines of the Red Sea, represent- ing one of the first steps for ongoing and future sampling efforts and studies.

关键词： Viral diversity Metagenomics Brine-seawater interface Caudovirales Red Sea

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Towards an Egyptian Mobile Banking Era

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Computer Technology and Application 2012年第11期3卷 765-773页

作者： Rehaballallah el Badrawy Pasha Abd el Aziz Meer hamza Business Information Systems Department Arab Academy for Science and Technology Alexandria 21311 Egypt Graduate School of Business Arab Academy for Science and Technology Alexandria 21311 Egypt

Banks have moved towards technology-based customer services such as mobile banking （m-banking）; as an alternative to traditional inter-personal services. However, M-banking still faces resistance that may hamper customers＇ adoption in Egypt. Following a mixed method approach, this study involves two main phases. First, a quantitative Consumer survey is conducted in the form of 350 structured questionnaires to identify the main barriers towards m-banking. Then, decision makers in 5 different public and private banks are interviewed in order to find similarities and difference, and identify service providers＇ roles regarding these barricrs. Questionnaire data was statistically analysed using independent T-Test, Chi-squares, frequencies and cross tabulations, while interview data was interpretively analysed. Results enabled the researchers to identify the risk, usage, and tradition as the most m-banking barriers that discourage m-banking adoption in Egypt as seen by the two main players.

关键词： Mobile banking intemet banking consumer resistance adoption barriers.

Genotypic characterization of Helicobacter pylori isolates among Egyptian patients with upper gastrointestinal diseases

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The Chinese-German Journal of Clinical Oncology 2012年第1期11卷 15-23页

作者： Abdel Hamid Hussein Ezzat Mona hamza Ali Eman Ahmed el-Seidi Iman Ezzat Wali Nagwa Abd el Rahman Sedky Sherif Medhat Mahmoud Naguib Department of Surgical Oncology National Cancer Institute Cairo University Laboratory Forensic Medicine Egyptian Ministry of Justice Medical Microbiology and Immunology Faculty of Medicine Cairo University Internal Medicine Faculty of Medicine Cairo University

Objective： Over 50% of the world populations are infected with Helicobacter pylori （H. pylori）. Most subjects are asymptomatic; however, in 1994, H. pylori has been categorized as group I carcinogen. The aim of the study was to investigate the relationship between H. pylori infection and gastric cancer. Methods： Thirty gastric cancer patients （GCs） and 30 gastritis patients were enrolled in the study. H. pylori was cultured on non-selective and selective medias, infection density was assessed by quantitative culture. Antibiotic sensitivity testing was performed. PCR was done for the H. pylori 16S rRNA gene in addition to cagA, vacA and iceA genes. Results： H. pylori could be cultured from 100% of specimens obtained from all patients. The density of H. pylori was higher in cancer cases than in gastritis patients. The 16S rRNA was detected in all GC patients （100%） while it was only detected in 70% of gastritis patients. The cagA gene was found in 53.3% vs 13.3% of GC and gastritis patients, respectively. The vacA gene was present in all GC patients （by at least one of its alleles） while it was only found in 33.3% of gastritis patients. The vacA slml combination was the most predominant genotype in GC patients, while m2 was the commonest allele in gastritis patients （10%）. The iceA gene was found in 86.7% vs 40% of GC and gastritis patients, respectively. Simultaneous presence of multiple H. pyiori strains was proved, both phenotypically and genotypically. Conclusion： The development of GC is linked to infection with H. pylori harboring certain virulence genes. Higher infection density of H. pylori was found in GC patients. Co-existence of more than one strain of H. pylori in the same patient occurs in both malignant and benign lesions.

关键词： Helicobacter pylori (H. pylori) pathogenesis virulence genes diagnosis infection density antibiotic resistance PCR

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Differential Evolution with Arithmetic Optimization Algorithm Enabled Multi-Hop Routing Protocol

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Computer Systems Science & Engineering 2023年第5期45卷 1759-1773页

作者： Manar Ahmed hamza Haya Mesfer Alshahrani Sami Dhahbi Mohamed K Nour Mesfer Al Duhayyim elSayed M.Tag el Din Ishfaq Yaseen Abdelwahed Motwakel Department of Computer and Self Development Preparatory Year DeanshipPrince Sattam bin Abdulaziz UniversityAlKharjSaudi Arabia Department of Information Systems College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Computer Science College of Science&Art at MahayilKing Khalid UniversityAbha62529Saudi Arabia Department of Computer Science College of Computing and Information SystemUmm Al-Qura UniversitySaudi Arabia Department of Computer Science College of Sciences and Humanities-AflajPrince Sattam bin Abdulaziz UniversitySaudi Arabia Department of electrical Engineering Faculty of Engineering and TechnologyFuture University in EgyptNew Cairo11845Egypt

Wireless Sensor Networks(WSN)has evolved into a key technology for ubiquitous living and the domain of interest has remained active in research owing to its extensive range of *** spite of this,it is challenging to design energy-efficient *** routing approaches are leveraged to reduce the utilization of energy and prolonging the lifespan of *** order to solve the restricted energy problem,it is essential to reduce the energy utilization of data,transmitted from the routing protocol and improve network *** this background,the current study proposes a novel Differential Evolution with Arithmetic Optimization Algorithm Enabled Multi-hop Routing Protocol(DEAOA-MHRP)for *** aim of the proposed DEAOA-MHRP model is select the optimal routes to reach the destination in *** accomplish this,DEAOA-MHRP model initially integrates the concepts of Different Evolution(DE)and Arithmetic Optimization Algorithms(AOA)to improve convergence rate and solution ***,the inclusion of DE in traditional AOA helps in overcoming local optima *** addition,the proposed DEAOA-MRP technique derives a fitness function comprising two input variables such as residual energy and *** order to ensure the energy efficient performance of DEAOA-MHRP model,a detailed comparative study was conducted and the results established its superior performance over recent approaches.

关键词： Wireless sensor network routing multihop communication arithmetic optimization algorithm fitness function

Analysis and Assessment of Wind Energy Potential of Almukalla in Yemen

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Computers, Materials & Continua 2022年第8期72卷 3113-3129页

作者： Murad A.A.Almekhlafi Fahd N.Al-Wesabi Majdy M.eltahir Anwer Mustafa Hilal Amin M.el-Kustaban Abdelwahed Motwakel Ishfaq Yaseen Manar Ahmed hamza Department of electrical Engineering–Communication Engineering Sana’a UniversityYemen Department of Computer Science King Khalid UniversityMuhayelAseerSaudi Arabia Faculty of Computer and IT Sana’a UniversitySana’aYemen Department of Information Systems King Khalid UniversityMuhayelAseerSaudi Arabia Department of Computer and Self Development Preparatory Year DeanshipPrince Sattam bin Abdulaziz UniversityAlKharjSaudi Arabia electronic Department Faculty of EngineeringUniversity of Science and TechnologySana’aYemen

Energy is an essential element for any civilized country’s social and economic development,but the use of fossil fuels and nonrenewable energy forms has many negative impacts on the environment and the *** Republic of Yemen has very good potential to use renewable ***,we find few studies on renewable wind energy in *** the lack of a similar analysis for the coastal city,this research newly investigates wind energy’s potential near the Almukalla area by analyzing wind ***,evaluation,model identification,determination of available energy density,computing the capacity factors for several wind turbines and calculation of wind energy were extracted at three heights of 15,30,and *** wind speeds were obtained only for the currently available data of five recent years,2005–*** study involves a preliminary assessment of Almukalla’s wind energy potential to provide a primary base and useful insights for wind engineers and *** research aims to provide useful assessment of the potential of wind energy in Almukalla for developing wind energy and an efficient wind *** Weibull distribution shows a perfect approximation for estimating the intensity of Yemen’s wind *** on both theWeibullmodel and the results of the annual wind speed data analysis for the study site in Mukalla,the capacity factor for many turbines was also calculated,and the best suitable turbine was *** to the International Wind Energy Rating criteria,Almukalla falls under Category 7,which is,rated“Superb”most of the year.

关键词： Almukalla energy potential Rayleigh distribution Weibull distribution wind power density wind speed