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Communications on Applied Mathematics and Computation 2024年第3期6卷 1899-1923页

作者： Sergio Torregrosa Victor Champaney amine ammar Vincent Herbert Francisco Chinesta PIMM Arts et Metiers Institute of Technology151 Boulevard de l'Hopital75013 ParisFrance STELLANTIS Route de Gisy78140 Velizy-VillacoublayFrance ESI Chair PIMMArts et Metiers Institute of Technology151 Boulevard de l'Hopital75013 ParisFrance ESI Chair LAMPAArts et Metiers Institute of Technology2 Boulevard du Ronceray49035 AngersFrance

The sampling of the training data is a bottleneck in the development of artificial intelligence(AI)models due to the processing of huge amounts of data or to the difficulty of access to the data in industrial *** learning(AL)approaches are useful in such a context since they maximize the performance of the trained model while minimizing the number of training *** smart sampling methodologies iteratively sample the points that should be labeled and added to the training set based on their informativeness and *** judge the relevance of a data instance,query rules are *** this paper,we propose an AL methodology based on a physics-based query *** some industrial objectives from the physical process where the AI model is implied in,the physics-based AL approach iteratively converges to the data instances fulfilling those objectives while sampling training ***,the trained surrogate model is accurate where the potentially interesting data instances from the industrial point of view are,while coarse everywhere else where the data instances are of no interest in the industrial context studied.

关键词： Active learning(AL) Artificial intelligence(AI) Optimization Physics based

Data-Driven Upscaling of Orientation Kinematics in Suspensions of Rigid Fibres

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Computer Modeling in Engineering & Sciences 2018年第12期117卷 367-386页

作者： Adrien Scheuer amine ammar Emmanuelle Abisset-Chavanne Elias Cueto Francisco Chinesta Roland Keunings Suresh GAdvani ICTEAM Universitécatholique de LouvainAv.Georges Lemaitre 4Louvain-la-Neuve B-1348Belgium Arts et Métiers ParisTech Boulevard du Ronceray 2BP 9352549035 Angers cedex 01France ICI&ESI GROUP Chair Ecole Centrale de NantesRue de la Noe 1F-44300 NantesFrance Aragon Institute of Engineering Research Universidad de ZaragozaEdificio Betancourt.Maria de Lunas.n.50018 ZaragozaSpain PIMM&ESI GROUP Chair ENSAM ParisTechBoulevard de l’Hopital 151F-75013 ParisFrance Deptartment of Mechanical Engineering University of DelawareNewarkDE 19716United States

Describing the orientation state of the particles is often critical in fibre suspension *** descriptors,the so-called second-order orientation tensor(or moment)leading the way,are often preferred due to their low computational *** problems however arise when evolution equations for the moments are derived from the orientation distribution functions and the impact of the chosen closure is often *** this work,our aim is to provide macroscopic simulations of orientation that are cheap,accurate and *** this end,we propose an innovative data-based approach to the upscaling of orientation kinematics in the context of fibre *** the physics at the microscopic scale can be modelled reasonably enough,the idea is to conduct accurate offline direct numerical simulations at that scale and to extract the corresponding macroscopic descriptors in order to build a database of *** the online stage,the macroscopic descriptors can then be updated quickly by combining adequately the items from the database instead of relying on an imprecise macroscopic *** methodology is presented in the well-known case of dilute fibre suspensions(where it can be compared against closure-based macroscopic models)and in the case of suspensions of confined or electrically-charged fibres,for which state-of-the-art closures proved to be inadequate or simply do not exist.

关键词： Fibre suspensions data-driven upscaling closure approximations

Improvement of mobility edge model by using new density of states with exponential tail for organic diode

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Chinese Physics B 2015年第4期24卷 360-365页

作者： Muhammad ammar Khan 孙久勋 School of Physical Electronics University of Electronic Science and Technology

The mobility edge （ME） model with single Gaussian density of states （DOS） is simplified based on the recent exper- imental results about the Einstein relationship. The free holes are treated as being non-degenerate, and the trapped holes are dealt with as being degenerate. This enables the integral for the trapped holes to be easily realized in a program. The J-V curves are obtained through solving drift-diffusion equations. When this model is applied to four organic diodes, an obvious deviation between theoretical curves and experimental data is observed. In order to solve this problem, a new DOS with exponential tall is proposed. The results show that the consistence between J-V curves and experimental data based on a new DOS is far better than that based on the Gaussian DOS. The variation of extracted mobility with temperature can be well described by the Arrhenius relationship.

关键词： organic diode potential barriers Einstein relationship

A critical review of intrusion detection systems in the internet of things:techniques,deployment strategy,validation strategy,attacks,public datasets and challenges

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Cybersecurity 2021年第1期4卷 251-277页

作者： Ansam Khraisat ammar Alazab Federation University Australia Federation University AustraliaBallaratAustralia

The Internet of Things(IoT)has been rapidly evolving towards making a greater impact on everyday life to large industrial ***,this has attracted the attention of cybercriminals who made IoT a target of malicious activities,opening the door to a possible attack on the end *** this end,Numerous IoT intrusion detection Systems(IDS)have been proposed in the literature to tackle attacks on the IoT ecosystem,which can be broadly classified based on detection technique,validation strategy,and deployment *** survey paper presents a comprehensive review of contemporary IoT IDS and an overview of techniques,deployment Strategy,validation strategy and datasets that are commonly applied for building *** also review how existing IoT IDS detect intrusive attacks and secure communications on the *** also presents the classification of IoT attacks and discusses future research challenges to counter such IoT attacks to make IoT more *** purposes help IoT security researchers by uniting,contrasting,and compiling scattered research ***,we provide a unique IoT IDS taxonomy,which sheds light on IoT IDS techniques,their advantages and disadvantages,IoT attacks that exploit IoT communication systems,corresponding advanced IDS and detection capabilities to detect IoT attacks.

关键词： Malware Intrusion detection system IoT Anomaly detection Machine learning Deep learning Internet of things Attacks IoT security

Robust SVM-direct torque control of induction motor based on sliding mode controller and sliding mode observer

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Frontiers in Energy 2020年第4期14卷 836-849页

作者： Abdelkarim ammar Amor BOUREK Abdelhamid BENAKCHA LGEB Laboratory Department of Electrical EngineeringUniversity of BiskraBiskraBP 145Algeria

This paper proposes a design of control and estimation strategy for induction motor based on the variable structure *** describes a coupling of sliding mode direct torque control(DTC)with sliding mode flux and speed *** algorithm uses direct torque control basics and the sliding mode approach.A robust electromagnetic torque and flux controllers are designed to overcome the conventional SVM-DTC draw・backs and to ensure fast response and full reference tracking with desired dynamic behavior and low ripple *** sliding mode controller is used to generate reference voltages in stationary frame and give them to the controlled motor after modulation by a space vector modulation(SVM)*** second aim of this paper is to design a sliding mode speed/flux observer which can improve the control performances by using a sensorless algorithm to get an accurate estimation,and consequently,increase the reliability of the system and decrease the cost of using *** effectiveness of the whole composed control algorithm is investigated in different robustness tests with simulation using Matlab/Simulink and verified by real time experimental implementation based on dS pace 1104 board.

关键词： induction motor direct torque control(DTC) space vector modulation(SVM) sliding mode control(SMC) sliding mode observer(SMO) dS1104

BLOWING UP AND MULTIPLICITY OF SOLUTIONS FOR A FOURTH-ORDER EQUATION WITH CRITICAL NONLINEARITY

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Acta Mathematica Scientia 2015年第6期35卷 1511-1546页

作者： Siwar ammar Mokhles HAMMAMI Department of mathematics University of Monastir Department of mathematics Faculty of Sciences of sfax University of Sfax

In this paper, we consider the following nonlinear elliptic problem ： △2u =｜u｜n-4^-u＋u｜u｜q-1u,in Ω,△u=u=0 on ЭΩ,where Ω is a bounded and smooth domain in R^n,n∈{5,6,7},u is a parameter and q∈]4/（n-4）,（12-n）/（n-4）].We study the solutions which concentrate around two points of Ω. We prove that the concentration speeOs are the same order and the distances of the concentration points from each other and from the boundary are bounded. For Ω=（Ωa）a a smooth ringshaped open set, we establish the existence of positive solutions which concentrate at two points of Ω. Finally, we show that for u〉0, large enough, the problem has at least many positive solutions as the Ljusternik-Schnirelman category of Ω.

关键词： fourth order elliptic equations critical Sobolev exponent blow up solution

EXISTENCE OF POSITIVE SOLUTIONS FOR A CLASS OF PARABOLIC EQUATIONS WITH NATURAL GROWTH TERMS AND L^1 DATA

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Acta Mathematica Scientia 2014年第4期34卷 1127-1144页

作者： Kaouther ammar Hicham REDWANE Department of Mathematics Faculty of sciencesTaibah UniversityP.O. Box 344 Al MadinahSaudi Arabia Facult'e des Sciences Juridiques Economiques et SocialesUniversit'e Hassan 1B.P. 784SettatMorocco

We study a class of nonlinear parabolic equations of the type：δb（u）/δt-div（a（x,t,u）△u）＋y（u）｜△u｜^2=f,where the right hand side belongs to L^1（Q）, b is a strictly increasing C^1-function and -div（a（x, t, u）△u） is a Leray-Lions operator. The function g is just assumed to be continuous on R and to satisfy a sign condition. Without any additional growth assumption on u, we prove the existence of a renormalized solution.

关键词： renormalized solutions natural growth terms L^1 data

Fake News Detection Using Machine Learning and Deep Learning Methods

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Computers, Materials & Continua 2023年第11期77卷 2079-2096页

作者： ammar Saeed Eesa Al Solami Department of Computer Science Comsats University IslamabadWah Cantt47010Pakistan Department of Cybersecurity College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia

The evolution of the internet and its accessibility in the twenty-first century has resulted in a tremendous increase in the use of social media *** social media sources contribute to the propagation of fake news that has no real validity,but they accumulate over time and begin to appear in the feed of every consumer producing even more *** sustain the value of social media,such stories must be distinguished from the true *** a result,an automated system is required to save time and *** classification of fake news and misinformation from social media data corpora is the subject of this *** preprocessing and data improvement procedures are used to gather and preprocess two fake news *** text features are extracted using word embedding models Word2vec and Global Vectors for Word representation while textual features are extracted using n-gram approaches named Term Frequency-Inverse Document Frequency and Bag of Words from both datasets *** Encoder Representations from Transformers(BERT)is also employed to derive embedded representations from the input ***,three Machine Learning(ML)and two Deep Learning(DL)algorithms are utilized for fake news *** also carries out the classification of embedded outcomes generated by it in parallel with the ML and DL *** terms of overall performance,the DL-based Convolutional Neural Network stands out in the case of the first while BERT performs better in the case of the second dataset.

关键词： Machine learning deep learning fake news feature extraction

A comprehensive simulator for assessing the reliability of a photovoltaic panel peak power tracking system

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Frontiers in Energy 2015年第2期9卷 170-179页

作者： Nabil KAHOUL Mourad HOUABES ammar NECAIBIA Laboratoire d' Electrotechnique d' Annaba Badji Mokhtar-AnnabaUniversity Annaba 23000 Algeria Research Unit of Renewable Energy in Saharan Middle (URER/MS) Adrar 01000 Algeria

When designing a maximum power point tracking （MPPT） algorithm, it is often difficult to correctly predict, before field testing, the behavior of this MPPT under varying solar irradiation on photovoltaic （PV） panels. A solution to this problem is to design a maximum power point trackers simulator of a PV system used to test MPPT algorithms. This simulator must have the same role as the MPPT card of the PV panel and thus will fully emulate the response of a real MPPT card of the PV panel. Therefore, it is a good substitute to help to test the peak power trackers of the PV system in the laboratory. This paper describes a simple peak power trackers simulator of the PV system which has a short response time thus, can be used to test MPPT algorithms under very rapid variation condition. The obtained results and the theoretical operation confirm the reliability and the superior perfor- mance of the proposed model.

关键词： photovoltaicdesign maximum powermicroprocessormodule DC-DC converter,point tracking (MPPT) card,

Interactive effects of deficit irrigation and vermicompost on yield,quality,and irrigation water use efficiency of greenhouse cucumber

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Journal of Arid Land 2022年第11期14卷 1274-1292页

作者： Halimeh PIRI Amir NASERIN ammar A ALBALASMEH Department of Water Engineering Faculty of College of Water and SoilUniversity of ZabolZabol ***Iran Department of Water Engineering Agricultural Sciences and Natural Resources University of KhuzestanMollasani ***Iran Department of Natural Resources and the Environment Faculty of AgricultureJordan University of Science and TechnologyIrbid 22110Jordan

Water scarcity is the most significant barrier to agricultural development in arid and semi-arid *** irrigation is an effective solution for managing agricultural water in these *** use of additives such as vermicompost(VC)to improve soil characteristics and increase yield is a popular *** this,there is still a lack of understanding of the interaction between irrigation water and VC on various *** study aimed to investigate the interaction effect of irrigation water and VC on greenhouse cucumber yield,yield components,quality,and irrigation water use efficiency(IWUE).The trials were done in a split-plot design in three replicates in a semi-arid region of southeastern Iran in 2018 and *** levels of VC in the experiments,i.e.,10(V_(1)),15(V_(2)),and 20 t/hm^(2)(V_(3)),and three levels of irrigation water,i.e.,50%(I_(1)),75%(I_(2)),and 100%(I_(3))of crop water requirement were *** results showed that the amount of irrigation water,VC,and their interaction significantly affected cucumber yield,yield components,quality,and IWUE in both *** the amount of irrigation water and VC application rates reduced the weight,diameter,length,and cucumber *** maximum yield(175 t/hm^(2))was recorded in full irrigation using 20 t/hm^(2)of VC,while the minimum yield(98 t/hm^(2))was found in I_(1)V_(1)*** maximum and minimum values of IWUE were recorded for I_(1)V_(3)and I_(3)V_(1)treatments as 36.07 and 19.93 kg/(m^(3)•hm^(2)),***,reducing irrigation amount decreased chlorophyll a and b,but increased vitamin ***,the maximum carbohydrate and protein contents were obtained in mild water-stressed conditions(I_(2)).Although adding VC positively influenced the value of quality traits,no significant difference was observed between V_(2)and V_(3)*** on the results,adding VC under full irrigation conditions leads to enhanced yield and ***,in the case of applying deficit ir

关键词： irrigation water use efficiency greenhouse size and weight of fruit soil amendment semi-arid region