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Chinese Physics B 2012年第3期21卷 321-327页

作者： Hacini k Meradji H Ghemid S El haj Hassan F Laboratoire LPR D'epartement de PhysiqueFaculté des SciencesUniversité de Annaba Laboratoire de physique des Matériaux Faculté des SciencesUniversité Libanaise

Within density functional theory based on the full potentiM-linearized augmented plane wave method, we carry out the first-principles calculation of the structural, electronic, and optical properties of the zinc blende quaternary alloy Zn1-xBexSySe1-y. The Perdew-Burke-Ernzerhof generaized gradient approximation based on the optimization of total energy and the Engel-Vosko generalized gradient approximation based on the optimization of the corresponding potential are used. Our investigation on the effect of the composition on lattice constants, bulk modulus, band gap, optical dielectric constant, and refractive index shows a non-linear dependence. The energy gap Eg（x, y） has been determined over the entire compositions x and y. In addition, the energy band gap of the technologically important quaternary alloy Znl-xBexSySe1-y in conditions of being lattice matched to ZnS substrate has been investigated. It is noteworthy that the present work is the first theoretical study of the quaternary alloy of interest.

关键词： density functional theory full potential-linearized augmented plane wave method qua-ternary alloy lattice-matched substrate

Efficient fall activity recognition by combining shape and motion features

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Computational Visual Media 2020年第3期6卷 247-263页

作者： Abderrazak Iazzi Mohammed Rziza Rachid Oulad haj Thami LRIT RABAT IT CENTERFaculty of SciencesUniversity of Mohammed 5 in RabatMorocco ADMIR LAB IRDARABAT IT CENTERENSIASUniversity of Mohammed 5 in RabatMorocco

This paper presents a vision-based system for recognizing when elderly adults fall.A fall is characterized by shape deformation and high *** represent shape variation using three features,the aspect ratio of the bounding box,the orientation of an ellipse representing the body,and the aspect ratio of the projection *** motion variation,we extract several features from three blocks corresponding to the head,center of the body,and feet using optical *** each block,we compute the speed and the direction of *** activity is represented by a feature vector constructed from variations in shape and motion features for a set of frames.A support vector machine is used to classify fall and non-fall *** on three different datasets show the effectiveness of our proposed method.

关键词： shape motion features

A Novel Probabilistic Hybrid Model to Detect Anomaly in Smart Homes

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Computer Modeling in Engineering & Sciences 2019年第12期121卷 815-834页

作者： Sasan Saqaeeyan Hamid haj Seyyed Javadi Hossein Amirkhani Department of Computer Engineering Borujerd BranchIslamic Azad UniversityBorujerdIran Department of Mathematics and Computer Science Shahed UniversityTehranIran Computer Engineering and Information Technology Department University of QomQomIran

Anomaly detection in smart homes provides support to enhance the health and safety of people who live *** to the previous studies done on this topic,less attention has been given to hybrid *** paper presents a two-steps hybrid probabilistic anomaly detection model in the smart ***,it employs various algorithms with different characteristics to detect anomalies from sensory ***,it aggregates their results using a Bayesian *** this Bayesian network,abnormal events are detected through calculating the probability of abnormality given anomaly detection results of base *** evaluation of a real dataset indicates the effectiveness of the proposed method by reducing false positives and increasing true positives.

关键词： Smart homes sensory data anomaly detection Bayesian networks ensemble method

Potential generated by a massive inhomogeneous straight segment

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Research in Astronomy and Astrophysics 2011年第3期11卷 345-352页

作者： Nour-Eddine Najid El haj Elourabi Mohamed Zegoumou Equipe Mécanique Statistique et Astronomie-Laboratoire de Physique Théorique et Appliquée Université Hassan Ⅱ Ain Chock-Faculté des Sciences Ain Chock BP 5366 Maarif Casablanca Morocco

The discoveries of binary asteroids have opened an important new field of research concerning the calculation of potential generated by irregular *** of them have an elongated shape.A simple model to describe the motion of a test particle in that kind of potential requires consideration of a finite homogeneous straight *** construct this model by adding an inhomogeneous distribution of mass. To be consistent with the geometrical shape of the asteroid,we explore a parabolic profile of the *** establish the closed analytical form of the potential generated by this inhomogeneous massive *** study of the dynamical behavior is fulfilled by the use of Lagrangian formulation,which allows us to calculate some two and three dimensional orbits.

关键词： asteroids—potential—inhomogeneous distribution

Hot compression deformation behavior of AISI 321 austenitic stainless steel

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International Journal of Minerals,Metallurgy and Materials 2013年第6期20卷 529-534页

作者： Mehdi haj Hojjatollah Mansouri Reza Vafaei Golam Reza Ebrahimi Ali kanani Department of Materials Engineering Malek Ashtar University of Technology Department of Materials and Polymer Engineering Faculty of Engineering Hakim Sabzevari University

The hot compression behavior of AISI 321 ll00~C and the strain rates of 0.01-1 s-1 using a Baehr austenitic stainless steel was studied at the temperatures of 950- DIL-805 deformation dilatometer. The hot deformation equations and the relationship between hot deformation parameters were obtained. It is found that strain rate and deformation temperature significantly influence the flow stress behavior of the steel. The work hardening rate and the peak value of flow stress increase with the decrease of deformation temperature and the increase of strain rate. In addition, the activation energy of deformation （Q） is calculated as 433.343 kJ/mol. The microstructural evolution during deformation indicates that, at the temperature of 950~C and the strain rate of 0.01 s-1, small circle-like precipitates form along grain boundaries; but at the temperatures above 950~C, the dissolution of such precipitates occurs. Energy-dispersive X-ray analyses indicate that the precipitates are complex carbides of Cr, Fe, Mn, Ni, and Ti.

关键词： austenitic stainless steel deformation constitutive equations microstructural evolution activation energy

Sustainability level of the pearl lobster(Panulirus ornatus)aquaculture business using the systems of floating-net cage and fixed-net cage:A case study in South Sulawesi Province,Indonesia

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Aquaculture and Fisheries 2024年第5期9卷 851-859页

作者： Nimmi Zulbainarni Muhammad Hairul haj Novindra School of Business Bogor Agricultural InstituteBogor16143Indonesia Tropical Marine Economics Study Program Bogor Agricultural InstituteBogor16680Indonesia Department of Resource Economics and Environment Bogor Agricultural InstituteBogor16680Indonesia

Marine aquaculture is currently the fastest-growing seafood industry globally,offering a potential solution to overfishing problems,while enhancing food security and income *** Sulawesi,a province in Indonesia,is rich in aquaculture resources,one of which is *** two commonly used aquaculture systems are the floating-net cage(kJA)and fixed-net cage(kJD).The growing market demand and rising lobster prices pose a threat to resource sustainability due to *** is issue have to be addressed to achieve sustainable fishery *** is the primary focus on global fishery *** to the United Nations,sustainable development encompasses three dimensions:the economy,social and ***,sustainable fishery,particularly aquaculture,relies on obtaining significant benefits while minimizing environmental ***,this study aimed to analyze the sustainability level of the pearl lobster(Panulirus ornatus)aquaculture in South Sulawesi,based on the provided background *** study included a sample of 62 *** sample selection involved the use of the stratified sampling method,with 51 farmers from(kJA)and 11 farmers from(kJD).The sustainability analysis,conducted through assessment of based farmers’perceptions,served as the analytical *** findings revealed that pearl lobster(Panulirus ornatus)aquaculture has a medium level of *** Integrated Multi Tropic Aquaculture(IMTA)and Regional Integrated Multi Tropic Aquaculture(RIMTA)techniques is a recommended sustainability level.

关键词： Cage Sustainability Pearl Lobster South Sulawesi Province Indonesia

Sensor Faults Observer Design with H_∞ Performance for Non-linear T-S systems

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International Journal of Automation and computing 2013年第6期10卷 563-570页

作者： Imen haj Brahim Maha Bouattour Driss Mehdi Mohamed Chaabane Ghani Hashim Laboratory of Sciences and Techniques of Automatic Control&Computer Engineering(Lab-STA) National School of Engineering of SfaxUniversity of Sfax LIAS-ENSIP University of PoitiersLIAS-ENSIP2 rue Pierre Brousse Computer Science Department Cihan University

This paper deals with the problem of the state estimation and the sensor faults detection for nonlinear perturbed systems described by Takagi-Sugeno （T-S） fuzzy models with unmeasurable premise variables. Indeed, a T-S observer is synthesized, in descriptor form, to estimate both the system states and the sensor faults simultaneously. The idea of the proposed approach is to introduce the sensor fault as an auxiliary variable in the state vector. Besides, the T-S model with unmeasurable premise variables is reduced to a perturbed model with measurable variables. Convergence conditions are established with Lyapunov theory and the H∞ performance in order to guarantee the best robustness to disturbances. These conditions are expressed in terms of linear matrix inequalities （LMIs）. The parameters of the observer are computed using the solution of the LMI conditions. Finally, a numerical example is given to illustrate the design procedures. Simulation results show the satisfactory performances.

关键词： Takagi-Sugeno (T-S) fuzzy system sensor faults H∞ performance descriptor approach observer linear matrix inequality(LMI).

Automated Safety System for Cars

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Automated Safety System for Cars

作者： haj Ahmed Ferid 北京邮电大学

学位级别：硕士

在过去的几百年里,汽车行业的创新带来了重要的科学进步,使得汽车变得更安全、更清洁,价格实惠。当今汽车工业是收入最大的经济部门之一。就从每个人拥有的车辆来说,其在改善人们生活质量方面发挥着重要作用。汽车被认为是我们生活中的... 详细信息

在过去的几百年里,汽车行业的创新带来了重要的科学进步,使得汽车变得更安全、更清洁,价格实惠。当今汽车工业是收入最大的经济部门之一。就从每个人拥有的车辆来说,其在改善人们生活质量方面发挥着重要作用。汽车被认为是我们生活中的一部分,它需要有最大的舒适度和安全度。汽车有着很大的优势,但也存在弊端。我们可以看到在一些汽车事故中,它所造成的人身伤害和死亡。汽车安全事故成为了五大死亡原因之首,因此汽车公司经常试图通过开发新技术去提高安全度,以满足顾客的需求。本项目以改善汽车的安全性和舒适性为目的,对未来汽车行业安全性和舒适性两方面进行初步调查,引领电子设计在新汽车系统中的整合。现代汽车的安全系统发达,但由于装备许多复杂的设备而变得昂贵。并且,现代汽车存在一些问题,如在加速器和制动器设计方面的问题容易导致人们误操作。这也是这个项目开展的原因,本项目的目标总结如下:-通过改变现有机械加速器为数字加速器,解决上述设计问题。-采用简单设备来确保驾驶员的安全和舒适。-便于保养。-更廉价,能够集成在较旧汽车里。

关键词：汽车系统安全系统汽车电子设备传感器汽车创新

Application of a probabilistic neural network in analysis of the radial velocity curve of spectroscopic binary stars

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Research in Astronomy and Astrophysics 2012年第12期12卷 1666-1672页

作者： kamal Ghaderi kayoomars karami Ali Pirkhedri Hamid haj Seyyed Javadi Touba Rostami Department of Science and Engineering Islamic Azad UniversityMarivan BranchMarivan Iran Department of Physics University of KurdistanPasdaran St.SanandajIran Department of Mathematics and Computer Science Faculty of Mathematics and Computer ScienceShahed UniversityTehranIran

Using measured radial velocity data of five double-lined spectroscopic binary systems,HD 89959,HD 143705,HD 146361,HD 165052 and HD 152248, we find corresponding orbital and spectroscopic elements via a Probabilistic ... 详细信息

关键词： stars:binaries:eclipsing-binaries:spectroscopic(HD 89959 HD 143705 HD 146361 HD 165052 and HD 152248)