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Journal of Hydrodynamics 2013年第5期25卷 788-804页

作者： TRAN KHANH Toan OUAHSINE Abdellatif naceur hakim EL WASSIFI Karima Laboratoire Roberval Université de Technologie de Compiègne Laboratoire LAMIH Université de Valenciennes Université Cadi Ayyad Faculté des Sciences et Techniques

In this paper, a numerical method based on a coupling between a mathematical model of nonlinear transient ship manoeuvring motion in the horizontal plane and Mathematical Programming （MP） techniques is proposed. The aim of the proposed procedure is an efficient estimation of optimal ship hydrodynamic parameters in a dynamic model at the early design stage. The proposed procedure has been validated through turning circle and zigzag manoeuvres based on experimental data of sea trials of the 190 000- dwt oil tanker. Comparisons between experimental and computed data show a good agreement of overall tendency in manoeuvring traiectories.

关键词： ship manoeuvrability hydrodynamics coefficients nonlinear transient dynamics sensitivity analysis mathematical pro- gramming

Impact of urban upgrading on perceptions of safety in informal settlements： Case study of Bouakal, Batna

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Frontiers of Architectural Research 2013年第4期2卷 400-408页

作者： Farida naceur Department of Architecture University of Batna Batna 05000 Algeria

This paper explores how modifications of urban space in informal settlements influence residents＇ quality of life and perceptions of safety. This is a case study of Bouakal, the oldest informal district in Batna, a middle city in Algeria. This paper examines the effects of urban improvement practices in Bouakal by exploring two questions： In what ways did interventions in this informal settlement affect the quality of life for the residents？ How do these effects correlate with changes in the perception of safety in this area？ The survey involved 141 residents from Bouakal, and local residents were selected to collect the levels of perceived safety. This paper concludes that urban upgrading has improved the quality of tile and has a positive effect on the perception of safety in the settlement.

关键词： Informal settlements Safety perception Fear of crime Urban upgrading

Potential risk of soil irrigation with treated wastewater over 40 years:a field experiment under semi-arid conditions in northeastern Tunisia

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Journal of Arid Land 2023年第4期15卷 407-423页

作者： Sarra HECHMI Samira MELKI Mohamed-naceur KHELIL Rim GHRIB Moncef GUEDDARI naceur JEDIDI Water Research and Technology Center University of CarthageSoliman 8020Tunisia National Institute for Research in Rural Engineering Water and ForestryAriana 2080Tunisia Faculty of Sciences of Tunis University of Tunis El ManarTunis 2092Tunisia

In Tunisia,water scarcity is only adding pressure on water demand in *** the context of sustainable development goals,Tunisia has been reusing treated wastewater(TWW)as a renewable and inexpensive source for soil fertigation and groundwater(GW)***,major risks can be expected when the irrigation water is of poor *** study aims for evaluating the potential risk of TWW and GW irrigation on soil ***,we evaluated the suitability of water quality through the analysis of major and minor cations and anions,metallic trace elements(MTEs),and the sodium hazard by using the sodium adsorption ratio(SAR)and the soluble sodium percentage(SSP).The risk of soil sodicity was further assessed by SAR and the exchangeable sodium percentage(ESP).The degree of soil pollution caused by MTEs accumulation was evaluated using geoaccumulation index(Igeo)and pollution load index(PLI).Soil maps were generated using inverse spline interpolation in ArcGIS *** results show that both water samples(i.e.,TWW and GW)are suitable for soil irrigation in terms of salinity(electrical conductivity5.00),followed by Ni^(2+)and Pb^(2+).Nevertheless,Cd^(2+)presents the lowest risk of soil pollution(Igeo50.0%).This study shows that the use of imagery tools,such as ArcGIS,can

关键词： treated wastewater metallic trace elements(MTEs) pollution indices sodium adsorption ratio(SAR) geoaccumulation index(Igeo) Tunisia

Effects of outdoor shared spaces on social interaction in a housing estate in Algeria

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Frontiers of Architectural Research 2013年第4期2卷 457-467页

作者： naceur Farida Department of Architecture University of Batna Batna 05000 Algeria

This study aims to identify how the characteristics of shared outdoor spaces in housing estates influence residents to interact with one another. The study specificalty focuses on a housing project catted la cite des 1000 logts, which is situated in a zone d＇habitat urbaine nouvelle in Biskra, a city in South Algeria. The investigation draws on two sources of information, observations of the ways in which the residents use their neighborhood spaces and a questionnaire survey with residents about the perceived adequacy of these spaces for social interaction. Data for the survey was collected from the owners of fiats in the apartment blocks surrounding the open spaces. Housing samples were taken from a total of 1000 housing units identified within the study area. Twenty five percent （25%） of the total housing units were selected. Out of the 250 questionnaires administered to household-heads who were the respondents, only 230 were subsecluently retrieved for data anatysis. Results showed that the high degree of ＂openness＂ of la cite des 1000 logts and the poor quatity of communal outdoor spaces in the area discourage art forms of spatial use and reduce these outdoor spaces to transit areas. Furthermore, findings indicated that the layout of buildings and the quality of common outdoor spaces in residential neighborhoods substantially affect the use of these spaces and the social interaction among residents.

关键词： Shared outdoor space Social interaction Desisn layout Housing estates

CeO2 nanoscale particles:Synthesis,characterization and photocatalytic activity under UVA light irradiation

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Journal of Rare Earths 2018年第6期36卷 575-587页

作者： Laouedj Nadjia Elaziouti Abdelkader Benhadria naceur Bekka Ahmed Laboratory of Inorganic Materials and Application L.I.M.A University of Science and Technology Oran Mohammed Boudiaf(USTO M.B)PB 1505 ElM'naouar31000 OranAlgeria Laboratory of Electron Microscopy and Materials Science L.E.M.M SUniversity of Science and Technology Oran Mohammed Boudiaf(USTO M.B)PB 1505E~M'naouar31000 OronAlgeria

CeO2nanoparticles(NPs) were synthesized in alkaline medium via the homogeneous precipitation method and were subsequently calcined at 80 ℃/24 h(assigned as CeO2-80) and 500 ℃/2 h(assigned as CeO2-500). The as-prepared materials and the commercial ceria(assigned as CeO2-com) were characterized using TGA-MS, XRD, SEM-EDX, UV-vis DRS and IEP techniques. The photocatalytic performances of all obtained photocatalysts were assessed by the degradation of Congo red azo-dye(CR) under UVAlight irradiation at various environmental key factors(e.g., reaction time and calcination temperature).Results reveal that CeO2compounds crystalize with cubic phase, CeO2-500 exhibits smaller crystallite size(9 nm vs 117 nm) than that of bare CeO2-com. SEM analysis shows that the materials are sphericallike in shape NPs with strong assembly of CeO2NPs observed in the CeO2-500 NPs. EDX analysis confirms the stoichiometry of CeO2NPs. UV-vis DRS measurement reveals that, CeO2-500 NPs exhibits a red-shift of absorption band and a more narrow bandgap(2.6 eV vs 3.20 eV) than that of bare CeO2-com. On the contrary, Urbach energy of Eu is found to be increased from 0.12 eV(CeO2-com) to 0.17 eV(CeO2-500),highlighting an increase of crystalline size and internal microstrain in the CeO2-500 NPs sample. Zeta potential(IEP) of CeO2-500 NPs is found to be 7.2. UVA-light-responsive photocatalytic activity is observed with CeO2-500 NPs at a rate constant of 10×10-3min-1, which is four times higher than that of CeO2-com(Kapp=2.4×10-3min-1) for the degradation of CR. Pseudo-first-order kinetic model gives the best fit. On the basis of the energy band diagram positions, the enhanced photocatalytic performance of CeO2-500 nano-catalyst can be ascribed to O2-, ’OH and R’+as the primary oxidative species involved in the degradation of RC under UVA-light irradiation.

关键词： CeO_2 NPs Congo red Photocatalytic activity Bandgap Urbach energy of Eu Band theory

Effect of sintering temperature on microstructure and electrical properties of Sr_(1-x)(Na_(0.5)Bi_(0.5))_(x)Bi_(2)Nb_(2)O_(9) solid solutions

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Journal of Advanced Ceramics 2014年第1期3卷 17-30页

作者： Hana naceur Adel MEGRICHE Mohamed EL MAAOUI Laboratory of Applied Mineral Chemistry Department of ChemistryFaculty of SciencesUniversity Tunis ElManarCampus 2092TunisTunisia

In this study,we investigated the effect of sintering temperature on densification,grain size,conductivity and dielectric properties of Sr_(1-x)(Na_(0.5)Bi_(0.5))_(x)Bi_(2)Nb_(2)O_(9) ceramics,prepared by hydrothermal *** were sintered at different *** increased with sintering temperature,reaching up to 96%at 800℃.A grain growth was observed with increasing sintering *** spectroscopy analyses of the sintered samples at various temperatures were *** in dielectric constant and in Curie temperature with sintering was *** conductivity and activation energy were calculated and attributed to the microstructural factors.

关键词： ceramics sintering light scattering dielectric properties

Resilient Control for Networked Control Systems Subject to Cyber/Physical Attacks

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International Journal of Automation and computing 2018年第3期15卷 345-354页

作者： Taouba Rhouma Karim Chabir Mohamed naceur Abdelkrim Modeling Analysis and Control of Systems(MACS) Laboratory National Engineering School of Gabes (ENIG)University of Gabes

In this paper, we investigate a resilient control strategy for networked control systems（NCSs） subject to zero dynamic attacks which are stealthy false-data injection attacks that are designed so that they cannot be detected based on control input and measurement data. Cyber resilience represents the ability of systems or network architectures to continue providing their intended behavior during attack and recovery. When a cyber attack on the control signal of a networked control system is computed to remain undetectable from passive model-based fault detection and isolation schemes, we show that the consequence of a zero dynamic attack on the state variable of the plant is undetectable during attack but it becomes apparent after the end of the attack. A resilient linear quadratic Gaussian controller, having the ability to quickly recover the nominal behavior of the closed-loop system after the attack end, is designed by updating online the Kalman filter from information given by an active version of the generalized likelihood ratio detector.

关键词： Networked control systems (NCSs) cyber physical attacks Kahnan filtering resilient control anomaly detector.

Effect of RC wall on the development of plastic rotation in the beams of RC frame structures

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Frontiers of Structural and Civil Engineering 2018年第3期12卷 318-330页

作者： Amar KAHIL Aghiles NEKMOUCHE Said BOUKAIS Mohand HAMIZI naceur Eddine HANNACHI Civil Engineering Department Faculty of Construction Engineering University Mouloud Mammeri Tizi-ouzou 15000 Algeria Civil Engineering Department Faculty of Technology University Abderrahmane Mira - Bejaia 06000 Algeria

The objective of this study is, to interpret the influence of reinforced concrete walls addition in reinforced concrete frame structures considering behavior laws that reflects the actual behavior of such structures, by means of Castem2000computer code （pushover analysis）. A finite element model is proposed in this study, using the TAKEDA modified behavior model with Timoshenko beams elements. This model is validated initially on experimental model. Then the work has focused on the behavior of a RC frame with 3 levels and three bays to better visualize the behavior of plastic hinges. Once the plastic hinge control parameters are identified （plastic rotation, ultimate curvature）, a strengthening by introduction of reinforced concrete walls （RC/wall） at the ends of the reinforced concrete frame （RC/ frame） has been performed. The results show that these RC walls significantly improve the behavior, by a relocation of efforts towards the central part of the beams.

关键词： RC/frame RC/wall moment curvature plastic rotation plastic hinge pushover analysis global models

Adaptive Fault Tolerant Control of Multi-time-scale Singularly Perturbed Systems

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International Journal of Automation and computing 2018年第6期15卷 736-746页

作者： Adel Tellili Nouceyba Abdelkrim Amina Challouf Mohamed naceur Abdelkrim Research Unit MACS University of Gabes Gabes Tunisia Higher Institute of Industrial Systems at Gabes University of Gabes Gabes Tunisia Higher Institute of Technological Studies at Djerba Djerba Tunisia National School of Engineers of Gabes University of Gabes Gabes Tunisia

This paper studies the fault tolerant control, adaptive approach, for linear time-invariant two-time-scale and three-time-scale singularly perturbed systems in presence of actuator faults and external disturbances. First, the full order system will be controlled using v-dependent control law. The corresponding Lyapunov equation is ill-conditioned due to the presence of slow and fast phenomena. Secondly, a time-scale decomposition of the Lyapunov equation is carried out using singular perturbation method to avoid the numerical stiffness. A composite control law based on local controllers of the slow and fast subsystems is also used to make the control law ε-independent. The designed fault tolerant control guarantees the robust stability of the global closed-loop singularly perturbed system despite loss of effectiveness of actuators. The stability is proved based on the Lyapunov stability theory in the case where the singular perturbation parameter is sufficiently small. A numerical example is provided to illustrate the proposed method.

关键词： Singularly perturbed systems time scale decomposition adaptive fault tolerant control actuator fault Lyapunov equations

New Biobased Polyurethane Materials from Modified Vegetable Oil

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Journal of Renewable Materials 2021年第7期9卷 1213-1223页

作者： Chakib Mokhtari Fouad Malek Sami Halila Mohamed naceur Belgacem Ramzi Khiari Laboratoire de Chimie Appliquée et Environnement–ECOMP—Facultédes Sciences UniversitéMohamed PremierOujda60000Maroc University of Grenoble Alpes CNRSCERMAVGrenobleCedex 9France University of Grenoble Alpes CNRSGrenoble INPGrenobleF-38000France University of Monastir Faculty of Sciences of MonastirResearch Unit of Applied Chemistry and EnvironmentMonastir5019Tunisia Higher Institute of Technological Studies(ISET)of Ksar-Hellal Ksar-Hellal5070Tunisia

Bio-based polyurethanes(PUs)have been occurred a large attention *** was found to be an alternative to the petrochemical based materials to the fact of their weak environmental influence,availability,good price and *** addition,the nature shows several bio-derived compounds as raw materials for the synthesis of polyols,including the vegetable oils,polyphenol,terpene,and other bio-renewable *** the aim to develop a new family of biobased polyurethanes(PUs)via vegetable oils,the elaboration of new Jojoba-based PUs was performed by catalyst-free polycondensation reaction of a synthesized Jojoba diol with various diisocyanates such us toluene diisocyanate(TDI)and isophorone diisocyanate(IPDI).All the compounds were characterized by FTIR and NMR spectroscopies,and their properties were determined by gel permeation chromatography,differential scanning calorimetry and thermogravimetric *** obtained results show renewable vegetable oils-based PUs materials can be preparing using a new environmentally ways and giving various good properties performances.

关键词： Biopolymers Jojoba oil polyurethane polyol thiol-ene