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Regional Controllability of Semi-Linear Distributed Parabolic Systems: Theory and Simulation

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Intelligent Control and Automation 2012年第2期3卷 146-158页

作者： asmae kamal Ali Boutoulout Sidi Ahmed Ould Beinane Department of Mathematics Al Jouf University College of Sciences Sakakah Kingdom of Saudi Arabia TSI Group Department of Mathematics and Computer Sciences Moulay Ismail University Faculty of Sciences Meknes Morocco

The aim of this brief paper is to give several results concerning the regional controllability of distributed systems governed by semi-linear parabolic equations. We concentrate on the determination of a control achieving internal and boundary regional controllability. The approach is based on an extension of the Hilbert Uniqueness Method (HUM) and Schauder’s fixed point theorem. We give a numerical example developed in internal and boundary sub region. These numerical illustrations show the efficiency of the approach and lead to conjectures.

关键词： Semi-Linear Parabolic Systems Regional Internal/Boundary Controllability Fixed-Point Theorems Distributed System HUM Approach

GPIO-Based Continuous Sliding Mode Control for Networked Control Systems Under Communication Delays With Experiments on Servo Motors

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 99-113页

作者： kamal Rsetam Zhenwei Cao Zhihong Man Xian-Ming Zhang the School of Software and Electrical Engineering Swinburne University of Technology the Department of Automated Manufacturing Al Khwarizmi College of Engineering University of Baghdad IEEE

To handle input and output time delays that commonly exist in many networked control systems(NCSs), a new robust continuous sliding mode control(CSMC) scheme is proposed for the output tracking in uncertain single input-single-output(SISO) networked control systems. This scheme consists of three consecutive steps. First, although the network-induced delay in those systems can be effectively handled by using Pade approximation(PA), the unmatched disturbance cames out as another difficulty in the control design. Second, to actively estimate this unmatched disturbance, a generalized proportional integral observer(GPIO) technique is utilized based on only one measured state. Third, by constructing a new sliding manifold with the aid of the estimated unmatched disturbance and states, a GPIO-based CSMC is synthesized, which is employed to cope with not only matched and unmatched disturbances, but also networkinduced delays. The stability of the entire closed-loop system under the proposed GPIO-based CSMC is detailedly *** promising tracking efficiency and feasibility of the proposed control methodology are verified through simulations and experiments on Quanser's servo module for motion control under various test conditions.

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Assessing trends in wildland-urban interface fire research through text mining: a comprehensive analysis of published literature

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Journal of Forestry Research 2024年第4期35卷 102-114页

作者： Hafsae Lamsaf asmae Lamsaf Mounir A.Kerroum Miguel Almeida ADAI–Associação para o Desenvolvimento da Aerodinâmica Industrial Rua Pedro Hispano n.º123030‑289 CoimbraPortugal Laboratory of Research in Computer Science Faculty of SciencesIbn Tofail UniversityKenitraMorocco

Research on fires at the wildland-urban inter-face(WUI)has generated significant insights and advance-ments across various fields of ***,agri-culture,and social sciences have played prominent roles in understanding the impacts of fires in the environment,in protecting communities,and addressing management *** study aimed to create a database using a text mining technique for global researchers interested in WUI-projects and highlighting the interest of countries in this ***’s-Keywords analysis emphasized the dominance of fire science-related terms,especially related to WUI,and identified keyword clusters related to the WUI fire-risk-assessment-system-“exposure”,“danger”,and“vulnerability”within wildfire *** over the past decade showcase shifting research interests with a growing focus on WUI fires,while regional variations highlighted that the“exposure”keyword cluster received greater atten-tion in the southern Europe and South ***,vulnerability keywords have relatively a lower representation across all *** analysis underscores the interdisci-plinary nature of WUI research and emphasizes the need for targeted approaches to address the unique challenges of the wildland-urban ***,this study provides valu-able insights for researchers and serves as a foundation for further collaboration in this field through the understanding of the trends over recent years and in different regions.

关键词： WUI Text mining Wildfires Fire science State of the art Scientific publications

Enhancing sustainability in phosphate ore processing:Performance of frying oil as alternative flotation collector for carbonate removal

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International Journal of Mining Science and Technology 2024年第4期34卷 557-571页

作者： asmae El-bahi Yassine Taha Yassine Ait-Khouia Abdellatif Elghali Mostafa Benzaazoua Geology&Sustainable Mining Institute(GSMI) Mohammed VI Polytechnic UniversityBen Guerir 43150Morocco

Recycling waste frying oils for the synthesis of flotation reagents presents a promising avenue for sustainable waste ***,it offers a cost-effective solution for crafting a specialized collector designed to efficiently remove carbonates and enhance phosphate enrichment in froth flotation *** study focuses on the synthesis of an anionic collector using the saponification reaction of a frying oil sample,subsequently applied to the flotation of calcite and *** elucidate the adsorption mechanisms of the frying oil collector(FrOC)and sodium oleate,a reference collector,on fluorapatite,calcite,dolomite,and quartz surfaces,comprehensive experiments were conducted,including zeta potential measurements and Fourier transform infrared *** revealed diverse adsorption affinities of the molecules towards these *** assess the practical performance of the collector,flotation tests were conducted using a natural phosphate ore mixture,employing a BoxBehnken experimental ***,under optimized conditions(pH 9,1000 g/t of FrOC,3.5 min of conditioning,and 6 min of flotation),FrOC exhibited excellent performance,with calcite and dolomite recoveries exceeding 80%,while apatite recovery in the concentrate fraction remained below 10%.This work exemplifies both circular economy practices and the distinctive approach to sustainable mineral processing.

关键词： Frying oils recycling Phosphate beneficiation Flotation separation Green surfactants Sustainability

Parameter Estimation Based on Censored Data under Partially Accelerated Life Testing for Hybrid Systems due to Unknown Failure Causes

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Computer Modeling in Engineering & Sciences 2022年第3期130卷 1239-1269页

作者： Mustafa kamal Department of Basic Sciences College of Science and Theoretical StudiesSaudi Electronic UniversityDammam32256Saudi Arabia

In general,simple subsystems like series or parallel are integrated to produce a complex hybrid *** reliability of a system is determined by the reliability of its constituent *** is often extremely difficult or impossible to get specific information about the component that caused the system to *** failure causes are instances in which the actual cause of systemfailure is *** the other side,thanks to current advanced technology based on computers,automation,and simulation,products have become incredibly dependable and trustworthy,and as a result,obtaining failure data for testing such exceptionally reliable items have become a very costly and time-consuming ***,because of its capacity to produce rapid and adequate failure data in a short period of time,accelerated life testing(ALT)is the most utilized approach in the field of product reliability and life *** on progressively hybrid censored(PrHC)data froma three-component parallel series hybrid system that failed to owe to unknown causes,this paper investigates a challenging problem of parameter estimation and reliability assessment under a step stress partially accelerated life-test(SSPALT).Failures of components are considered to follow a power linear hazard rate(PLHR),which can be used when the failure rate displays linear,decreasing,increasing or bathtub failure *** Tempered random variable(TRV)model is considered to reflect the effect of the high stress level used to induce early failure *** maximum likelihood estimation(MLE)approach is used to estimate the parameters of the PLHR distribution and the acceleration factor.A variance covariance matrix(VCM)is then obtained to construct the approximate confidence intervals(ACIs).In addition,studentized bootstrap confidence intervals(ST-B CIs)are also constructed and compared with ACIs in terms of their respective interval lengths(ILs).Moreover,a simulation study is conducted to demonstrate the

关键词： Step stress partially accelerated life test progressive hybrid censoring data masking power linear hazard rate distribution hybrid system

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Journal of Systems Science & Complexity 2019年第3期32卷 737-758页

作者： BERAHMAND kamal BOUYER Asgarali Department of Information Technology and Communications Azarbaijan Shahid Madani University

Community structure is one of the most best-known proper ties of complex networks. Finding communities help us analyze networks from a mesoscopic viewpoints instead of microscopic or macroscopic one. It helps to understand behavior grouping. Various community detection algorithms have been proposed with some shortcomings in time and space complexity, accuracy, or stability. Label Propagation Algorithm (LPA) is a popular method used for finding communities in an almost-linear time-consuming process. However, its performance is not satisfactory in some metrics such as accuracy and stability. In this paper, a new modified version of LPA is proposed to improve the stability and accuracy of the LPA by defining two concepts -nodes and link strength based on semi-local similarity-, while preserving its simplicity. In the proposed method a new initial node selection strategy, namely the tiebreak strategy, updating order and rule update are presented to solve the random behavior problem of original LPA. The proposed algorithm is evaluated on artificial and real networks. The experiments show that the proposed algorithm is close to linear time complexity with better accuracy than the original LPA and other compared met hods. Furthermore, the proposed algorithm has the robustness and stability advantages while the original LPA does not have these features.

关键词： Community detection complex networks LPA similarity measure

Atomistic Line Graph Neural Network for improved materials property predictions

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npj Computational Materials 2021年第1期7卷 1691-1698页

作者： kamal Choudhary Brian DeCost Materials Measurement Laboratory National Institute of Standards and TechnologyGaithersburgMD 20899USA Theiss ResearchLa Jolla California 92037USA DeepMaterials LLC Silver SpringMD 20906USA

Graph neural networks(GNN)have been shown to provide substantial performance improvements for atomistic material representation and modeling compared with descriptor-based machine learning *** most existing GNN models for atomistic predictions are based on atomic distance information,they do not explicitly incorporate bond angles,which are critical for distinguishing many atomic ***,many material properties are known to be sensitive to slight changes in bond *** present an Atomistic Line Graph Neural Network(ALIGNN),a GNN architecture that performs message passing on both the interatomic bond graph and its line graph corresponding to bond *** demonstrate that angle information can be explicitly and efficiently included,leading to improved performance on multiple atomistic prediction *** ALIGNN models for predicting 52 solid-state and molecular properties available in the JARVIS-DFT,Materials project,and QM9 *** can outperform some previously reported GNN models on atomistic prediction tasks by up to 85%in accuracy with better or comparable model training speed.

关键词： explicitly property passing

Designing high-TC superconductors with BCS-inspired screening,density functional theory,and deep-learning

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npj Computational Materials 2022年第1期8卷 2331-2342页

作者： kamal Choudhary Kevin Garrity Material Measurement Laboratory GaithersburgMD20899USA National Institute of Standards and Technology GaithersburgMD20899USA Theiss Research La JollaCA92037USA

We develop a multi-step workflow for the discovery of conventional superconductors,starting with a Bardeen–Cooper–Schrieffer inspired pre-screening of 1736 materials with high Debye temperature and electronic density of ***,we perform electron-phonon coupling calculations for 1058 of them to establish a large and systematic database of BCS superconducting *** the McMillan-Allen-Dynes formula,we identify 105 dynamically stable materials with transition temperatures,TC≥5 ***,we analyze trends in our dataset and individual materials including MoN,VC,VTe,KB_(6),Ru_(3)NbC,V_(3)Pt,ScN,LaN_(2),RuO_(2),and *** demonstrate that deep-learning(DL)models can predict superconductor properties faster than direct first-principles ***,we find that by predicting the Eliashberg function as an intermediate quantity,we can improve model performance versus a direct DL prediction of *** apply the trained models on the crystallographic open database and pre-screen candidates for further DFT calculations.

关键词： database BCS faster

EXISTENCE AND NONEXISTENCE OF SOLUTIONS FOR A HARMONIC EQUATION WITH CRITICAL NONLINEARITY

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Acta Mathematica Scientia 2016年第5期36卷 1305-1316页

作者： kamal OULD BOUH Department of Mathematics College of Sciences Taibah University

This paper is concerned with the harmonic equation(P;) : ?u = 0, u > 0 in B;and ?u/?ν+(（n-2）/2)u =(（n-2）/2) Ku;on S;where B;is the unit ball in R;, n ≥ 4 with Euclidean metric g;, ?B;= S;is its boundary, K is a function on S;and ε is a small positive parameter. We construct solutions of the subcritical equation(P;) which blow up at one critical point of K. We give also a sufficient condition on the function K to ensure the nonexistence of solutions for(P;) which blow up at one point. Finally, we prove a nonexistence result of single peaked solutions for the supercritical equation(P;).

关键词： variational problem critical points harmonic equation mean curvature critical exponent