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Improving Channel Estimation in a NOMA Modulation Environment Based on Ensemble Learning

Computer Modeling in Engineering & sciences 2024年第8期140卷 1315-1337页

作者： lassaad k.s.irani Leila Jamel Latifah Almuqren Elearning Deanship and Distance Education Umm Al-Qura UniversityP.O.Box 715MekkahSaudi Arabia Department of Information systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia

This study presents a layered generalization ensemble model for next generation radio mobiles,focusing on supervised channel estimation *** estimation typically involves the insertion of pilot symbols with a well-balanced rhythm and suitable *** model,called stacked Generalization for Channel Estimation(sGCE),aims to enhance channel estimation performance by eliminating pilot insertion and improving *** sGCE model incorporates six machine learning methods:random forest(RF),gradient boosting machine(GB),light gradient boosting machine(LGBM),support vector regression(sVR),extremely randomized tree(ERT),and extreme gradient boosting(XGB).By generating meta-data from five models(RF,GB,LGBM,sVR,and ERT),we ensure accurate channel coefficient predictions using the XGB *** validate themodeling performance,we employ the leave-one-out cross-validation(LOOCV)approach,where each observation serves as the validation set while the remaining observations act as the training *** performances’results demonstrate higher mean andmedian accuracy compared to the *** achieves an average accuracy of 98.4%,precision of 98.1%,and the highest F1-score of 98.5%,accurately predicting channel ***,our proposedmethod outperforms prior traditional and intelligent techniques in terms of throughput and bit error ***’s superior performance highlights its efficacy in optimizing channel *** can effectively predict channel coefficients and contribute to enhancing the overall efficiency of radio mobile *** extensive experimentation and evaluation,we demonstrate that sGCE improved performance in channel estimation,surpassing previous ***,sGCE’s capabilities have significant implications for optimizing channel estimation in modern communication systems.

关键词： stacked generalization ensemble learning Non-Orthogonal Multiple Access(NOMA) channel estimation 5G

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Geochemistry, mineral paragenesis and geothermal conditions of oreforming fluids from the Ain El Bey Cu–Fe deposit: potential occurrence of native gold and precious metal traces (North African orogenic belt, Northern Tunisia)

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Acta Geochimica 2024年第2期43卷 366-384页

作者： Rania Ben Aissa Wiem Ben Aissa said Tlig lassaad Ben Aissa Abdessalem Ben Haj Amara Faculty of science of Bizerte University of Carthage7021 ZarzounaBizerteTunisia Laboratoire de Recherche Ressources Materiaux et EcosystemesUniversity of Carthage7021 ZarzounaBizerteTunisia Department of Geology University Claude Bernard Lyon 169622 VilleurbanneFrance Faculty of science of Tunis University of Tunis-El ManarRommana1068 TunisTunisia

The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petromineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. scanning Electron Microscope--Energy Dispersive spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores(tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 ℃ for phase Ⅲ, from 254 to 350 ℃ for phase Ⅳ, and from 200 to 300 ℃ for phases Ⅴ and Ⅵ. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature(s. such results open up perspectives for the development of precious metal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary.

关键词： Ore-formingﬂuids Mineral geochemistry Mineral geothermometers Native silver-gold Ain El Bey Ore deposit North Tunisia

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Bubble hydrodynamic influence on oxygen transfer rate at presence of cationic and anionic surfactants in electroflotation process

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Journal of Hydrodynamics 2013年第5期25卷 747-754页

作者： kOTTI Mariam ksENTINI Issam BEN MANsOUR lassaad Laboratory of Applied Fluid Mechanics Process Engineering and EnvironmentScience Faculty of Sfax

In this work, the effects of the presence of surfactants in the liquid phase and the hydrodynamic regime of the bubble flow on the oxygen transfer rate were investigated in an electroflotation process in batch mode. The volumetric mass transfer coefficient kLα and the oxygenation capacity were evaluated to improve the performances of the electroflotation process in terms of oxygenation. In order to evaluate the liquid-side mass transfer coefficient kLα the volumetric mass transfer coefficient kLα was dissociated into kL and the specific interracial area （a） since the last one was obtained from the gas hold-up and the bubble diameter. The effect of Reynolds number which define the hydrodynamic of the bubble flow has been also studied. Models of kLa and kL have been established to show the effects of the hydrodynamic parameters and liquid phase characteristics on the oxygen transfer rate.

关键词： electroflotation mass transfer coefficient hydrodynamic parameters surfactant

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Usability-Driven Mobile Application Development

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Computer systems science & Engineering 2023年第6期45卷 3165-3180页

作者： Fadwa Yahya lassaad Ben Ammar Gasmi karim Prince sattam Bin Abdulaziz University AlkharjSaudi Arabia University of sfax SfaxTunisia Department of Computer sciences Faculty of Sciences and Arts in TABARJALJouf UniversityKingdom of Saudi Arabia

Recently,a specific interest is being taken in the development of mobile application(app)via Model-Based User Interface Development(MBUID)*** allows the generation of mobile apps in the target platform(s)from conceptual *** such it simplified the development process of mobile ***,the interest is only focused on the functional aspects of the mobile app while neglecting the non-functional aspects,such as *** latter is largely considered as the main factor leading to the success or failure of any software *** paper aims at addressing non-functional aspects of mobile apps generated using MBUID *** such,we propose a usability-driven approach for the development of mobile *** main stages of the proposed approach are defined in a generic way so that they can be integrated with any MBUID method.A case study is presented,in the paper,with the aim of illustrating the feasibility of this approach.

关键词： Mobile application user interface model-based user interface development mobile usability

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Prediction of Uncertainty Estimation and Confidence Calibration Using Fully Convolutional Neural Network

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Computers, Materials & Continua 2023年第5期75卷 2557-2573页

作者： karim Gasmi lassaad Ben Ammar Hmoud Elshammari Fadwa Yahya Department of Computer science College of Arts and Sciences at TabarjalJouf UniversityJoufSaudi Arabia College of sciences and Humanities Prince Sattam Bin Abdulaziz UniversityAl-KharjSaudi Arabia University of sfax SfaxTunisia Department of Information systems College of Computer and Information SciencesJouf UniversityJoufSaudi Arabia

Convolution neural networks(CNNs)have proven to be effective clinical *** study highlighted some of the key issues within these *** is difficult to train these systems in a limited clinical image databases,and many publications present strategies including such learning ***,these patterns are known formaking a highly reliable *** addition,normalization of volume and losses of dice have been used effectively to accelerate and stabilize the ***,these systems are improperly regulated,resulting in more confident ratings for correct and incorrect classification,which are inaccurate and difficult to *** study examines the risk assessment of Fully Convolutional Neural Networks(FCNNs)for clinical image *** contributions have been made to this planned work:1)dice loss and cross-entropy loss are compared on the basis of segment quality and uncertain assessment of FCNNs;2)proposal for a group model for assurance measurement of full convolutional neural networks trained with dice loss and group normalization;And 3)the ability of the measured FCNs to evaluate the segment quality of the structures and to identify test examples outside the *** evaluate the study’s contributions,it conducted a series of tests in three clinical image division applications such as heart,brain and *** findings of the study provide significant insights into the predictive ambiguity assessment and a practical strategies for outside-distribution identification and reliable measurement in the clinical image *** approaches presented in this research significantly enhance the reliability and accuracy rating of CNNbased clinical imaging methods.

关键词： Medical image segmentation confidence calibration uncertainty estimation fully convolutional neural network

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Influence of vertical loads on lateral response of pile foundations in sands and clays

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第2期9卷 291-304页

作者： lassaad Hazzar Mahmoud N.Hussien Mourad karray Department of Civil Engineering Faculty of EngineeringSherbrooke University Department of Civil Engineering Faculty of EngineeringAssiut University

Although the load applied to pile foundations is usually a combination of vertical and lateral components,there have been few investigations on the behavior of piles subjected to combined *** few studies led to inconsistent results with regard to the effects of vertical loads on the lateral response of piles.A series of three-dimensional(3D) finite differences analyses is conducted to evaluate the influence of vertical loads on the lateral performance of pile *** idealized sandy and clayey soil profiles are considered:a homogeneous soil layer,a layer with modulus proportional to depth,and two-layered *** pile material is modeled as linearly elastic,while the soil is idealized using the Mohr-Coulomb constitutive model with a non-associated flow *** order to confirm the findings of this study,soils in some cases are further modeled using more sophisticated models(*** model for sandy soils and modified Cam-Clay(MCC) model for clayey soils).Numerical results showed that the lateral resistance of the piles does not appear to vary considerably with the vertical load in sandy soil especially at the loosest ***,the presence of a vertical load on a pile embedded in homogeneous or inhomogeneous clay is detrimental to its lateral capacity,and it is unconservative to design piles in clays assuming that there is no interaction between vertical and lateral ***,the current results indicate that the effect of vertical loads on the lateral response of piles embedded in twolayered strata depends on the characteristics of soil not only surrounding the piles but also located beneath their tips.

关键词： Pile foundations Vertical loads Lateral loads Finite differences Mohr circle

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Two mitochondrial haplotypes in Pterochloroides persicae （Hemiptera： Aphididae： Lachninae） associated with different feeding sites

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Insect science 2013年第5期20卷 637-642页

作者： Mdellel lassaad David Martinez-Torres Ben Halima kamel Monia Hight Institute of Agronomy Chott Mariem 4042 Sousse Tunisia Institut Cavanilles de Biodiversitat i Biologia Evolutiva Universitat de Valencia Apdo. Correos 22085 46071 Valencia Spain

Pterochloroides persicae （Cholodkovsky） is an aphid species belonging to the subfamily Lachninae that uses different members of Rosaceae （specially Prunus spp.） as hosts. Partial sequences from the mitochondrial cytochrome c oxidase 1 （COI） and the nuclear long-wave opsin genes were obtained for approximately 100 P. persicae aphid individuals sampled from 34 colonies collected mainly in Tunisia and other Mediterranean locations. The variability found at the mitochondrial locus revealed the presence of two maternal haplotypes in the studied area that differed in a single nucleotide. The nuclear gene analyzed, however, failed to reveal any variability in this species. The variability found at the COI locus was related to the season of aphid sampling and with the site of feeding, with haplotype I mostly detected in samples collected in spring and summer on trunks and branches and haplotype II only detected in aphids collected in autumn on roots. The observed pattern of molecular variation suggests the presence of two clonal races of P. persicae coexisting in the studied area differentially adapted to conditions prevalent in the alternative seasons and/or to different feeding sites.

关键词： aphids COI Lachninae life cycle Pterochloroides variability

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Acute effects of chlorpyryphos-ethyl and secondary treated effluents on acetylcholinesterase and butyrylcholinesterase activities in Carcinus maenas

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Journal of Environmental sciences 2009年第10期21卷 1467-1472页

作者： Jihene Ghedira Jamel Jebali Zied Bouraoui Mohamed Banni lassaad Chouba Hamadi Boussetta Laboratory of Biochemical and Environmental Toxicology Higher Institute of Agriculture Chott-Mariem 4042 Sousse Tunisia Chemical Laboratory Higher Institute of Marine Sciences and Technology La Goulette Center 2060 Tunisia

The acute effects of commercial formulation of chlorpyrifos-ethyl （Dursban ） and the secondary treated industrial/urban effluent （sTIUE） exposure on acetylcholinesterase （ACHE） and butyrylcholinesterase （BuChE） activities in hepatopancreas and gills of Mediterranean crab Carcinus maenas were investigated. After 2 d of exposure to chlorpyriphos-ethyl, the AChE activity was inhibited in both organs at concentrations of 3.12 and 7.82 μg/L, whereas the BuCHE was inhibited only at higher concentration 7.82 μg/L of commercial preparation Dursban~. The exposure of crabs to Dursban （3.12 μg/L） showed a significant decrement of ACHE activity at 24 and 48 h, whereas the BuChE was inhibited only after 24 h and no inhibition for both enzymes was observed after 72 h. Moreover, a significant repression of AChE activity was observed in both organs of C. maenas exposed to 5% of sTIUE. Our experiments indicated that the measurement of AChE activity in gills and hepatopancreas of C. maenas would be useful biomarker of organophosphorous （OP） and of neurotoxic effects of sTIUE in Tunisia.

关键词： acetylcholinesterase butyrylcholinesterase organophosphorous Dursban secondary treated industrial/urban effluent Carcinus maenas

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symbolic generation of the kinematics of multibody systems in EasyDyn: From MuPAD to Xcas/Giac

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Theoretical & Applied Mechanics Letters 2013年第1期3卷 89-94页

作者： Olivier Verlinden lassaad Ben Fkih Georges kouroussis Department of Theoretical Mechanics Dynamics and Vibrations University of Mons

In the EasyDyn multibody open source project, computer algebra has been used from the beginning to generate the expressions of velocities and accelerations of the bodies, by symbolic differentiation of their position. Originally, the MuPAD computer algebra system had been retained because it was freely available for non commercial purposes and showed very good technical ***, MuPAD is nowadays only available through commercial channels and needs to be replaced to keep EasyDyn publicly available. This paper presents why Xcas/Giac is finally selected,among other long-term promising projects like Axiom, Maxima, sage or Yacas. Among the choice criteria, the accessibility, the portability, the ease of use, the automatic export to C language, and the similarity with the -MuPAD language are all considered. The performances of the MuPAD and Xcas/Giac implementations are also compared on some examples.C 2013 The Chinese society of Theoretical and Applied Mechanics. [doi：10.1063/2.13013012]

关键词： symbolic multibody systems kinematics computer algebra system open source

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Innovative hydrophobic/hydrophilic perfluoropolyether(PFPE)/polyvinylidene fluoride(PVDF)composite membrane for vacuum membrane distillation

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Chinese Journal of Chemical Engineering 2022年第5期35卷 248-257页

作者： Jun Pan Xianli Xu Zhaohui Wang shi-Peng sun Zhaoliang Cui lassaad Gzara Iqbal Ahmed Omar Bamaga Mohammed Albeirutty Enrico Drioli state key Laboratory of Materials-Oriented Chemical Engineering College of Chemistry and Chemical EngineeringNanjing Tech UniversityNanjing 210009China National Engineering Research Center for special separation Membrane Nanjing Tech UniversityNanjing 210009China Jiangsu National synergetic Innovation Center for Advanced Materials(sICAM) Nanjing Tech UniversityNanjing 210009China Center of Excellence in Desalination Technology King Abdulaziz UniversityJeddah 21589Saudi Arabia Mechanical Engineering Department King Abdulaziz UniversityJeddah 21589Saudi Arabia Research Institute on Membrane Technology ITM-CNRVia Pietro Bucci 17/CRende 87036Italy

Though membrane distillation(MD)has gained more and more attention in the field of desalination,the wetting phenomenon was still a non-negligible *** this work,a method combined dip-coating and UV in situ polymerization for preparing hydrophobic/hydrophilic perfluoropolyether(PFPE)/polyvinylidene fluoride composite *** composite membrane consisted of a top thin hydrophobic coating layer and hydrophilic substrate *** terms of anti-wetting properties,contact angle and liquid entry pressure of all composite membranes(except for those based on 0.45μm)exceeded 160°and 0.3 MPa,*** particular,the desalination performance was tested in vacuum membrane distillation tests by feeding 3.5%(mass)saline solution(NaCl)at 60℃.The composite membranes with larger support pore size and lower PFPE content had higher membrane distillation *** for stability tests(testing the 0.22μm membrane coated by 5%(mass)PFPE),the highest MD flux29.08 kg·m^(-2)·h^(-1) and stable salt rejection(over 99.99%)during the *** that,the effects of coating material concentration and pore sizes of substrate membrane were also investigated for surface morphology and topography,porosity,mechanical strength and pore size *** work provided a simple and effective alternative to prepare excellent hydrophobic composite membranes for MD applications.

关键词： Desalination Membrane surface coating Composite membranes Anti-wetting Vacuum membrane distillation

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