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Journal of Materials Science & Technology 2020年第6期41卷 209-218页

作者： bassem barkia Pascal Aubry Paul Haghi-Ashtiani Thierry Auger Lionel Gosmain Frédéric Schuster Hicham Maskrot DEN-Service d’Etudes Analytiques et de Réactivitédes Surfaces CEAUniversitéParis-Saclay91191France Laboratoire de Mécanique des Sols Structures et MatériauxCentralesupélecUMR CNRS 8579UniversitéParis-Saclay92295France Arts et Métiers ParisTech PIMMUMR CNRS 800675013 ParisFrance CEA Cross-Cutting Program on Materials and Processes Skills 91191Gif-sur-YvetteFrance

We report that 316L austenitic stainless steel fabricated by direct laser deposition(DLD),an additive manufacturing(AM)process,have a higher yield strength than that of conventional 316L while keeping high *** interestingly,no clear anisotropy in tensile properties was observed between the building and the scanning direction of the 3D printed *** examination of the as-built parts shows a heterogeneous solidification cellular *** electron microscopy observations coupled with Energy Dispersive X-ray Spectrometry(EDS)reveal the presence of chemical micro-segregation correlated with high dislocation density at cell boundaries as well as the in-situ formation of well-dispersed oxides and transition-metal-rich *** hierarchical heterogeneous microstructure in the AM parts induces excellent strength of the 316L stainless steel while the low staking fault energy of the as-built 316L promotes the occurrence of abundant deformation twinning,in the origin of the high ductility of the AM *** additional post-process treatments,the AM 316L proves that it can be used as a structural material or component for repair in mechanical construction.

关键词： Additive manufacturing Austenitic stainless steel Dislocation structure Twinning Mechanical behavior Anisotropy

Experimental flexural behavior of SMA-FRP reinforced concrete beam

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Frontiers of Structural and Civil Engineering 2013年第4期7卷 341-355页

作者： Adeel ZAFAR bassem ANDRAWES Department of Civil Engineering University of Illinois at Urbana-ChampaignIllinois 61820USA

The most critical drawback in currently used steel reinforcement in reinforced concrete(RC)structures is susceptibility to accumulation of plastic deformation under excessive *** concrete structures due to damaged(yielded)steel reinforcement have undergone costly repairs and *** research presents a new type of shape memory alloy(SMA)-based composite reinforcement with ability to withstand high elongation while exhibiting pseudoelastic *** this study,small diameter SMA wires are embedded in thermoset resin matrix with or without additional glass fibers to develop composite *** technique of new proposed composite is validated using microscopy *** proposed SMA-FRP composite square rebars are first fabricated and then embedded in small scale concrete T-beam.3-point bending test is conducted on manufactured RC beam using a cyclic displacement controlled regime until *** is found that the SMA-FRP composite reinforcement is able to enhance the performance of concrete member by providing re-centering and crack closing capability.

关键词： re-centering shape memory alloys concrete composite fiber reinforced polymer scanning electron microscopy

Practical stabilization of a class of uncertain time-varying nonlinear delay systems

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控制理论与应用（英文版） 2009年第2期7卷 175-180页

作者： bassem Ben HAMED Mohamed Ali HAMMAMI Institut Supérieur des Sciences Appliquées et de Technologie de Gabès Département de MathématiquesRue Amor Ben El Khatab 6029 GabèsTunisia Faculté des Sciences de Sfax Département de Mathématiques BP 802 Route Soukra km 4 Sfax 3018Tunisia

In this paper we deal with a class of uncertain time-varying nonlinear systems with a state delay. Under some assumptions, we construct some stabilizing continuous feedback, i.e. linear and nonlinear in the state, which can guarantee global uniform exponential stability and global uniform practical convergence of the considered system. The quadratic Lyapunov function for the nominal stable system is used as a Lyapunov candidate function for the global system. The results developed in this note are applicable to a class of dynamical systems with uncertain time-delay. Our result is illustrated by a numerical example.

关键词： Nonlinear system Time-delay Feedbacks Practical convergence Lyapunov function

Absolute Stability of Nonlinear Systems with Two Additive Time-varying Delay Components

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International Journal of Automation and computing 2011年第4期8卷 391-402页

作者： bassem Ben Hamed Mohamed Chaabane Walid Kacem Higher Institute of Applied Sciences and Technology of Gab`es Department of Mathematics Street Amor Ben El Khatab 6029 Gab`es Tunisia National Engineering School of Sfax Department of Electrical Engineering Street Soukra km 3.5 B.P. 1173 3038 Sfax Tunisia

In this paper, we present a new sufficient condition for absolute stability of Lure system with two additive time-varying delay components. This criterion is expressed as a set of linear matrix inequalities （LMIs）, which can be readily tested by using standard numerical software. We use this new criterion to stabilize a class of nonlinear time-delay systems. Some numerical examples are given to illustrate the applicability of the results using standard numerical software.

关键词： Time-varying delay system additive delay absolute stability linear matrix inequalities (LMIs) S-procedure Lyapunov Krasovskii functional stabilization.

Effects of C_8 ventral root avulsion or transection on spinal alpha motoneurons in adult rats A qualitative light and electron microscopic study

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Neural Regeneration Research 2008年第2期3卷 148-156页

作者： Khulood M.AL-Khater bassem Y.Sheikh Department of Anatomy College of MedicineKing Faisal UniversityDammam Department of Neurosurgery College of MedicineTaibah UniversityMadinahSaudi Arabia

BACKGROUND： Nerve root avulsion is a frequent finding in patients with brachial plexus injury following road traffic accidents or as a result of severe arm traction during complicated deliveries. This injury constitutes a challenging clinical and surgical problem. The morphological characteristics of motoneurons after nerve root avulsion deserve further analysis. OBJECTIVE： To study the different morphological changes of α-motoneurons under light and electron microscopy after C8 spinal ventral rootlets avulsion and transection at various stages. DESIGN： Controlled animal study. SETTING： Department of Anatomy, King Faisal University. MATERIALS： The experiment was carried out at the Department of Anatomy, College of Medicine, King Faisal University between January 2005 and March 2006. Six adult Sprague Dawley rats weighing 200-350 g, irrespective of gender, were used for this study. The animals were bred at the animal house, College of Medicine, King Faisal University, and fed on rat maintenance diet. Water and standard diet were supplied ad libitum. Animal interventions were carried out according to animal ethical standards. METHODS： Three animals were randomly chosen for avulsion of the right ventral rootlets of C8 spinal nerves. The other three received transection of the right ventral rootlets of C8 spinal nerves. ①Avulsion experiment： After rats were anesthetized, the right ventral rootlets of C8 spinal nerves were identified. The ventral rootlets were avulsed from the spinal cord by traction with a fine hook （Fine Science Tools Inc., No. 10031-13, Germany）. Traction was exerted in a direction parallel to the course of the spinal root. Under the operating microscope, the C8 segment was exactly located. After checking the successfulness of the surgical procedure, the C8 segment was separated from the spinal cord. The outcome of the avulsion procedure was as follows： two animals had true avulsion, i.e., no remaining stump was attached to the spinal cord sur

关键词： nerve root avulsion transection

Bogdanov–Takens Bifurcation in a Neutral Delayed Hopfield Neural Network with Bidirectional Connection

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International Journal of Biomathematics 2020年第6期13卷 163-177页

作者： Houssem Achouri Chaouki Aouiti bassem Ben Hamed University of Carthage Faculty of Sciences of BizerteDepartment of MathematicsResearch Units of Mathematics and Applications UR13ES47BP W7021 ZarzounaBizerteTunisia Ecole Nationale d'Eledronique et des Telecommunications de Sfax Technopole El OnsRoute de Tunis km 10BP 11633021 SfaxTunisia

In this paper,a neutral Hopfield neural network with bidirectional connection is *** the first step,by choosing the connection weights as parameters bifurcation,the critical point at which a zero root of multiplicity two occurs in the characteristic equation associated with the linearized *** the second step,we studied the zeros of a third degree exponential polynomial in order to make sure that except the double zero root,all the other roots of the characteristic equation have real parts that are ***,we find the critical values to guarantee the existence of the Bogdanov–Takens *** the third step,the normal form is obtained and its dynamical behaviors are studied after the use of the reduction on the center manifold and the theory of the normal ***,for the demonstration of our results,we have given a numerical example.

关键词： Neutral Hopfield neural networks time delay Bogdanov-Takens bifurcation center manifold normal form

Experimental and theoretical investigation of high-entropy-alloy/support as a catalyst for reduction reactions

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Journal of Energy Chemistry 2023年第6期81卷 132-142,I0005页

作者： Wail Al Zoubi bassem Assfour Abdul Wahab Allaf Stefano Leoni Jee-Hyun Kang Young Gun Ko Materials Electrochemistry Laboratory School of Materials Science and EngineeringYeungnam UniversityGyeongsan 38541Republic of Korea Atomic Energy Commission Department of ChemistryP.O.Box 6091DamascusSyria Arab International University Department of Pharmaceutical Chemistry and Quality ControlFaculty of PharmacyGhabaghibDarraSyria Cardiff University School of ChemistryPark PlaceCF103AT CardiffUnited Kingdom School of Materials Science and Engineering Institute of Materials TechnologyYeungnam UniversityGyeongsan 38541Republic of Korea

Control of chemical composition and incorporation of multiple metallic elements into a single metal nanoparticle(NP)in an alloyed or a phase-segregated state hold potential scientific merit;however,developing libraries of such structures using effective strategies is challenging owing to the thermodynamic immiscibility of repelling constituent metallic ***,we present a one-pot interfacial plasma-discharge-driven(IP-D)synthesis strategy for fabricating stable high-entropy-alloy(HEA)NPs exhibiting ultrasmall size on a porous support ***,an electric field was applied for 120 s to enhance the incorporation of multiple metallic elements(i.e.,CuAgFe,CuAgNi,and CuAgNiFe)into ally ***,NPs were attached to a porous magnesium oxide surface via rapid *** solar light as the sole energy input,the CuAgNiFe catalyst was investigated as a reusable and sustainable material exhibiting excellent catalytic performance(100%conversion and 99% selectivity within1 min for a hydrogenation reaction)and consistent activity even after 20 cycles for a reduction reaction,considerably outperforming the majority of the conventional ***,the proposed strategy establishes a novel method for designing and synthesizing highly efficient and stable catalysts for the convertion of nitroarenes to anilines via chemical reduction.

关键词： Plasma Miscible Multicomponent Metal nanoparticle Nanocatalysts

Multi-dimensional Security Range Query for Industrial IoT

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Computers, Materials & Continua 2022年第7期72卷 157-179页

作者： Abdallah Abdallah Ayman A.Aly bassem F.Felemban Imran Khan Ki-Il Kim School of Engineering Technology Al Hussein Technical University(HTU)Amman11831Jordan Department of Mechanical Engineering College of EngineeringTaif UniversityTaif21944Saudi Arabia Department of Electrical Engineering University of Engineering and Technology PeshawarPakistan Department of Computer Science and Engineering Chungnam National UniversityDaejeon34134Korea

The Internet of Things(IoT)has allowed for significant advancements in applications not only in the home,business,and environment,but also in factory *** Internet of Things(IIoT)brings all of the benefits of the IoT to industrial contexts,allowing for a wide range of applications ranging from remote sensing and actuation to decentralization and *** expansion of the IoT has been set by serious security threats and obstacles,and one of the most pressing security concerns is the secure exchange of IoT data and fine-grained access control.A privacypreserving multi-dimensional secure query technique for fog-enhanced IIoT was proposed in light of the fact that most existing range query schemes for fog-enhanced IoT cannot provide both multi-dimensional query and privacy *** query matrix was then decomposed using auxiliary vectors,and the auxiliary vectorwas then processed usingBGNhomomorphic encryption to create a query ***,the query trapdoor may be matched to its sensor data using the homomorphic computation used by an IoT device *** the application of particular auxiliary vectors,the spatial complexity might be efficiently *** homomorphic encryption property might ensure the security of sensor data and safeguard the privacy of the user’s inquiry *** results of the experiments reveal that the computing and communication expenses are modest.

关键词： Internet of things data security ciphertext privacy encryption

Modeling and numerical investigation of slow crack growth and crack arrest in ceramic polycrystals

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Theoretical & Applied Mechanics Letters 2013年第5期3卷 53-57页

作者： bassem El Zoghbi Rafael Estevez Christian Olagnon Laboratoire SIMAP UMR CNRS 5266 Grenoble-INP UJF Universite' de Grenoble Laboratoire MATEIS UMR CNRS 5510 INSA Lyon Universite' de Lyon69621 France

ntergranular slow crack growth in zirconia polycrystal is described with a cohesive zone model that simulate mechanically the reaction-rupture mechanism underlying stress and environ- mentally assisted failure. A 2D polycrystal is considered with cohesive surfaces inserted along the grain boundaries. The anisotropic elastic modulus and grain-to-grain misorientation are accounted for together with an initial stress state related to the processing. A minimum load threshold is shown to originate from the onset of the reaction-rupture mechanism to proceed where a minimum traction is reached locally and from the magnitude of the initial compression stresses. This work aims at providing reliable predictions in long lasting applications of ceramics.

关键词： zirconia ceramic slow crack growth cohesive zone intergranular failure

Modelling the dynamics of stock market in the gulf cooperation council countries:evidence on persistence to shocks

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Financial Innovation 2022年第1期8卷 1252-1273页

作者： Heni Boubaker bassem Saidane Mouna Ben Saad Zorgati Institute of High Commercial Studies(IHEC)of Sousse LaREMFiQB.P.404054 SousseTunisia IPAG Business School IPAG LAB184 Boulevard Saint-Germain75006 ParisFrance

This study examines the statistical properties required to model the dynamics of both the returns and volatility series of the daily stock market returns in six Gulf Cooperation Council countries,namely Bahrain,Oman,Kuwait,Qatar,Saudi Arabia,and the United Arab Emirates,under different financial and economic *** empiri-cal investigation is conducted using daily data from June 1,2005 to July 1,*** analysis is conducted using a set of double long-memory specifications with some significant features such as long-range dependencies,asymmetries in conditional variances,non-linearity,and multiple seasonality or time-varying *** study indicates that the joint dual long-memory process can adequately estimate long-memory dynamics in returns and *** in-sample diagnostic tests as well as out-of-sample forecasting results demonstrate the prevalence of the Autoregressive Fractionally Integrated Moving Average and Hyperbolic Asymmetric Power Autoregressive Conditional Heteroskedasticity modeling process over other competing models in fitting the first and the second conditional moments of the market ***,the empirical results show that the proposed model offers an interesting framework to describe the long-range dependence in returns and seasonal persistence to shocks in conditional volatility and strongly support the estimation of dynamic returns that allow for time-varying correlations.A noteworthy finding is that the long-memory dependencies in the conditional variance processes of stock market returns appear important,asymmetric,and differ in their volatility responses to unexpected *** evidence suggests that these markets are not completely efficient in processing regional news,thus providing a sound alternative for regional portfolio diversification.

关键词： Long-memory Volatility process Asymmetric power Seasonality Forecast performance Stock market