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AN ADAPTIVE VERSION OF GLIMM'S SCHEME

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Acta Mathematica Scientia 2010年第2期30卷 428-446页

作者： H.Kim M.Laforest D.Yoon Department of Mathematics Korea University Département de mathématiques et génie industriel cole Polytechnique de MontréalMontréalQuébec

This article describes a local error estimator for Glimm＇s scheme for hyperbolic systems of conservation laws and uses it to replace the usual random choice in Glimm＇s scheme by an optimal choice. As a by-product of the local error estimator, the procedure provides a global error estimator that is shown numerically to be a very accurate estimate of the error in L1 （R） for all times. although there is partial mathematical evidence for the error estimator proposed, at this stage the error estimator must be considered ad- hoc. Nonetheless, the error estimator is simple to compute, relatively inexpensive, without adjustable parameters and at least as accurate as other existing error estimators. Numerical experiments in 1-D for Burgers＇ equation and for Euler＇s system are performed to measure the asymptotic accuracy of the resulting scheme and of the error estimator.

关键词： conservation laws finite difference methods adaptive error estimation aposteriori

Metal oxide ion gated transistors based sensors

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Science China(Technological Sciences) 2024年第4期67卷 1040-1060页

作者： LI Yang YAO Yu WANG LeLe WANG LiWei PANG YunCong LUO ZhongZhong ARUNPRABAHARAN Subramanian LIU ShuJuan ZHAO Qiang College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Nanjing University of Posts&Telecommunications(NJUPT)Nanjing 210023China State Key Laboratory of Organic Electronics and Information Displays&Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)Nanjing University of Posts&Telecommunications(NJUPT)Nanjing 210023China Department of Chemical Engineering Polytechnique MontréalMontréalQuébec H3C3J7Canada

Metal oxide ion-gated transistors(MOIGTs)have garnered significant attention within the sensing domain due to their potential for achieving heightened sensitivity while consuming minimal energy across diverse scenarios.By harnessing the advantageous combination of metal oxides'high carrier mobility and facile surface customization,coupled with the potent signal amplification capabilities of ion-gated transistors,MOIGTs offer a promising avenue for discerning biomolecules,overseeing chemical reactions,p H levels,as well as facilitating gas or light determination.Over the past few decades,the MOIGT field has made remarkable strides in refining device physics,enhancing material properties,showcasing robust sensing capabilities,and broadening its application spectrum.These advancements have simultaneously unveiled new challenges and opportunities,necessitating interdisciplinary expertise to fully unlock the commercial potential of MOIGTs.In this comprehensive review,we offer a snapshot of this swiftly evolving technology,delve into its current applications,and provide insightful recommendations for future directions in the coming decade.

关键词： sensors ion gated transistors metal oxide semiconductors biosensors chemosensors pH sensors

Corrosion and in vitro cytocompatibility investigation on the designed Mg-Zn-Ag metallic glasses for biomedical application

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Journal of Magnesium and alloys 2024年第4期12卷 1566-1580页

作者： Jian Wang Lingzhong Meng Weixin Xie Chen Ji Ronghua Wang Pinghu Zhang Liling Jin Liyuan Sheng Yufeng Zheng School of Mechanical Engineering Yangzhou UniversityYangzhou225127China Department of Materials Science and Engineering Seoul National UniversitySeoulSouth Korea Huizhou Port Customs Huizhou516081China Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Diseases Institute of Translational MedicineMedical CollegeYangzhou UniversityYangzhou225009China Center for Research in Computational Thermochemistry(CRCT) Department of Chemical EngineeringEcole polytechnique de MontréalMontréalQuébecH3C 3A7Canada Shenzhen Institute Peking UniversityShenzhen 518057China PKU-HKUST ShenZhen-HongKong Institution Shenzhen518057China

In the present work,seven Mg-Zn-Ag alloys with the nominal composition of Mg_(96-x)Zn_(x)Ag_(4)(x=17,20,23,26,29,32,35 in at.%)were prepared by induction melting and single-roller melt-spinning.The X-ray diffraction(XRD)analyses indicate the metallic glasses with three composition of Mg_(73)Zn_(23)Ag_(4),Mg_(70)Zn_(26)Ag_(4),and Mg_(67)Zn_(29)Ag_(4)were obtained successfully.The differential scanning calorimetry(DSC)measurement was used to obtain the characteristic temperature of Mg-Zn-Ag metallic glasses for the glass-forming ability analysis.The maximum glass transition temperature(Trg)was found to be 0.525 with a composition close to Mg_(67)Zn_(29)Ag_(4),which results in the best glass-forming ability.Moreover,the immersion test in simulated body fluid(SBF)demonstrate the relative homogeneous corrosion behavior of the Mg-Zn-Ag metallic glasses.The corrosion rate of Mg-Zn-Ag metallic glasses in SBF solution decreases with the increase of Zn content.The sample Mg_(67)Zn_(29)Ag_(4)has the lowest corrosion rate of 0.19mm/yr,which could meet the clinical application requirement well.The in vitro cell experiments show that the Madin-Darby canine kidney(MDCK)cells cultured in sample Mg_(67)Zn_(29)Ag_(4)and its extraction medium have higher activity.However,the Mg-Zn-Ag metallic glasses exhibit obvious inhibitory effect on human rhabdomyosarcoma(RD)tumor cells.The present investigations on the glass-forming ability,corrosion behavior,cytocompatibility and tumor inhibition function of the Mg-Zn-Ag based metallic glass could reveal their biomedical application possibility.

关键词： Metallic glasses Mg-Zn-Ag Corrosion behavior In vitro cytocompatibility

Combining thermal scanning probe lithography and dry etching for grayscale nanopattern amplification

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Microsystems & Nanoengineering 2024年第1期10卷 335-344页

作者： Berke Erbas Ana Conde-Rubio Xia Liu Joffrey Pernollet Zhenyu Wang Arnaud Bertsch Marcos Penedo Georg Fantner Mitali Banerjee Andras Kis Giovanni Boero Juergen Brugger Microsystems Laboratory École Polytechnique Fédérale de Lausanne(EPFL)Lausanne 1015Switzerland Center of MicroNanoTechnology(CMi) EPFLLausanne 1015Switzerland Laboratory of Nanoscale Electronics and Structures École Polytechnique Fédérale de Lausanne(EPFL)Lausanne 1015Switzerland Laboratory for Bio-and Nano-Instrumentation École Polytechnique Fédérale de Lausanne(EPFL)Lausanne 1015Switzerland Laboratory of Quantum Physics Topology and CorrelationsÉcole Polytechnique Fédérale de Lausanne(EPFL)Lausanne 1015Switzerland Present address:Institute of Materials Science of Barcelona ICMAB-CSIC Campus UABBellaterra 08193Spain Present address:School of Integrated Circuits and Electronics MIIT Key Laboratory for Low-Dimensional Quantum Structure and DevicesBeijing Institute of TechnologyBeijing 100081China

Grayscale structured surfaces with nanometer-scale features are used in a growing number of applications in optics and fluidics.Thermal scanning probe lithography achieves a lateral resolution below 10 nm and a vertical resolution below 1 nm,but its maximum depth in polymers is limited.Here,we present an innovative combination of nanowriting in thermal resist and plasma dry etching with substrate cooling,which achieves up to 10-fold amplification of polymer nanopatterns into SiO_(2) without proportionally increasing surface roughness.Sinusoidal nanopatterns in SiO_(2) with 400 nm pitch and 150 nm depth are fabricated free of shape distortion after dry etching.To exemplify the possible applications of the proposed method,grayscale dielectric nanostructures are used for scalable manufacturing through nanoimprint lithography and for strain nanoengineering of 2D materials.Such a method for aspect ratio amplification and smooth grayscale nanopatterning has the potential to find application in the fabrication of photonic and nanoelectronic devices.

关键词： lithography thermal pattern

Programming nonlinear propagation for efficient optical learning machines

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Advanced Photonics 2024年第1期6卷 73-83页

作者： Ilker Oguz Jih-Liang Hsieh Niyazi Ulas Dinc Ugur Tegin Mustafa Yildirim Carlo Gigli Christophe Moser Demetri Psaltis École polytechnique Fédérale de Lausanne Institute of Electrical and Micro EngineeringEcublensSwitzerland Koc University Department of Electrical and Electronics EngineeringIstanbulTurkey

The ever-increasing demand for training and inferring with larger machine-learning models requires more efficient hardware solutions due to limitations such as power dissipation and scalability.Optics is a promising contender for providing lower power computation,since light propagation through a nonabsorbing medium is a lossless operation.However,to carry out useful and efficient computations with light,generating and controlling nonlinearity optically is a necessity that is still elusive.Multimode fibers(MMFs)have been shown that they can provide nonlinear effects with microwatts of average power while maintaining parallelism and low loss.We propose an optical neural network architecture that performs nonlinear optical computation by controlling the propagation of ultrashort pulses in MMF by wavefront shaping.With a surrogate model,optimal sets of parameters are found to program this optical computer for different tasks with minimal utilization of an electronic computer.We show a remarkable decrease of 97%in the number of model parameters,which leads to an overall 99%digital operation reduction compared to an equivalently performing digital neural network.We further demonstrate that a fully optical implementation can also be performed with competitive accuracies.

关键词： neural networks nonlinear optics fiber optics surrogate optimization neuromorphic computing wavefront shaping

Enhancing Renewable Energy Integration:A Gaussian-Bare-Bones Levy Cheetah Optimization Approach to Optimal Power Flow in Electrical Networks

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1339-1370页

作者： ali S.alghamdi Mohamed A.Zohdy Saad aldoihi Department of Electrical Engineering College of EngineeringMajmaah UniversityAl-Majmaah11952Saudi Arabia Electrical and Computer Engineering Department Oakland UniversityRochesterMI48309USA Institute of Earth and Space Science King Abdulaziz City for Science and Technology(KACST)Riyadh11442Saudi Arabia Computer Science and Systems Engineering Institute Polytechnique de ParisPalaiseau CedexFrance

In the contemporary era,the global expansion of electrical grids is propelled by various renewable energy sources(RESs).Efficient integration of stochastic RESs and optimal power flow(OPF)management are critical for network optimization.This study introduces an innovative solution,the Gaussian Bare-Bones Levy Cheetah Optimizer(GBBLCO),addressing OPF challenges in power generation systems with stochastic RESs.The primary objective is to minimize the total operating costs of RESs,considering four functions:overall operating costs,voltage deviation management,emissions reduction,voltage stability index(VSI)and power loss mitigation.Additionally,a carbon tax is included in the objective function to reduce carbon emissions.Thorough scrutiny,using modified IEEE 30-bus and IEEE 118-bus systems,validates GBBLCO’s superior performance in achieving optimal solutions.Simulation results demonstrate GBBLCO’s efficacy in six optimization scenarios:total cost with valve point effects,total cost with emission and carbon tax,total cost with prohibited operating zones,active power loss optimization,voltage deviation optimization and enhancing voltage stability index(VSI).GBBLCO outperforms conventional techniques in each scenario,showcasing rapid convergence and superior solution quality.Notably,GBBLCO navigates complexities introduced by valve point effects,adapts to environmental constraints,optimizes costs while considering prohibited operating zones,minimizes active power losses,and optimizes voltage deviation by enhancing the voltage stability index(VSI)effectively.This research significantly contributes to advancing OPF,emphasizing GBBLCO’s improved global search capabilities and ability to address challenges related to local minima.GBBLCO emerges as a versatile and robust optimization tool for diverse challenges in power systems,offering a promising solution for the evolving needs of renewable energy-integrated power grids.

关键词： Renewable energy integration optimal power flow stochastic renewable energy sources gaussian-bare-bones levy cheetah optimizer electrical network optimization carbon tax optimization

Dual Control Strategy for Grid-tied Battery Energy Storage Systems to Comply with Emerging Grid Codes and Fault Ride Through Requirements

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Journal of Modern Power Systems and Clean Energy 2022年第4期10卷 977-988页

作者： Maxime Berger Ilhan Kocar Evangelos Farantatos Aboutaleb Haddadi Department of Electrical Engineering Polytechnique MontréalMontréalCanada Electric Power Research Institute(EPRI) Palo AltoUSA

Battery energy storage systems(BESSs)need to comply with grid code and fault ride through(FRT)requirements during disturbances whether they are in charging or discharging mode.Previous literature has shown that constant charging current control of BESSs in charging mode can prevent BESSs from complying with emerging grid codes such as the German grid code under stringent unbalanced fault conditions.To address this challenge,this paper proposes a new FRTactivated dual control strategy that consists of switching from constant battery current control to constant DC-link voltage control through a positive droop structure.The results show that the strategy ensures proper DC-link voltage and current management as well as adequate control of the positive-and negative-sequence active and reactive currents according to the grid code priority.It is also shown that the proposed FRT control strategy is tolerant to initial operating conditions of BESS plant,grid code requirements,and fault severity.

关键词： Battery energy storage system inverter-based resource fault ride through electromagnetic transient

Catalytic Effect of Transition Metal Complexes of Triaminoguanidine on the Thermolysis of Energetic NC/DEGDN Composite

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火炸药学报 2024年第3期47卷 209-219,I0003页

作者： Mohammed Dourari Ahmed Fouzi Tarchoun Djalal Trache Amir Abdelaziz Roufaida Tiliouine Tessnim Barkat Weiqiang Pang Energetic Materials Laboratory(EMLab) Teaching and Research Unit of Energetic ProcessesEcole Militaire PolytechniqueBP 17Bordj El-Bahri16046AlgiersAlgeria Xi′an Modern Chemistry Research Institute Xi′an 710065China

The transition metal complexes of triaminoguanidine(TAG-M,where M=Cobalt(Co)or Iron(Fe))have been prepared.The catalytic effect of these complexes on the thermolysis of energetic composite based on nitrocellulose and diethylene glycol dinitrate,has been investigated.Extensive characterization of the resulting energetic composites was carried out using scanning electron microscopy(SEM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and differential scanning calorimetry(DSC).Isoconversional kinetic analysis was performed to determine the Arrhenius parameters associated with the thermolysis of the elaborated energetic formulations.It is found that TAG-M complexes have strong catalytic effect on the thermo-kinetic decomposition of NC/DEGDN by decreasing the apparent activation energy and significantly increased the total heat release.The models that govern the decomposition processes are also studied,and it is revealed that different reaction processes are accomplished by introduction metal complexes of triaminoguanidine.Overall,this study serves as a valuable reference for future research focused on the investigation of catalytic combustion features of solid propellants.

关键词： triaminoguanidine transition metal complexes nitrocellulose diethylene glycol dinitrate catalytic effect

NFA:A neural factorization autoencoder based online telephony fraud detection

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Digital Communications and Networks 2024年第1期10卷 158-167页

作者： Abdul Wahid Mounira Msahli albert Bifet Gerard Memmi Department of Computer Sciences and Networks(INFRES) LTCITelecom ParisInstitut Polytechnique de ParisPalaiseau91120France Artificial Inteligence Institute The University of WaikatoPrivate Bag 31053240HamiltonNew Zealand

The proliferation of internet communication channels has increased telecom fraud,causing billions of euros in losses for customers and the industry each year.Fraudsters constantly find new ways to engage in illegal activity on the network.To reduce these losses,a new fraud detection approach is *** fraud detection involves identifying a small number of fraudulent calls from a vast amount of call traffic.Developing an effective strategy to combat fraud has become challenging.although much effort has been made to detect fraud,most existing methods are designed for batch processing,not real-time detection.To solve this problem,we propose an online fraud detection model using a Neural Factorization Autoencoder(NFA),which analyzes customer calling patterns to detect fraudulent calls.The model employs Neural Factorization Machines(NFM)and an Autoencoder(AE)to model calling patterns and a memory module to adapt to changing customer behaviour.We evaluate our approach on a large dataset of real-world call detail records and compare it with several state-of-the-art methods.Our results show that our approach outperforms the baselines,with an AUC of 91.06%,a TPR of 91.89%,an FPR of 14.76%,and an F1-score of 95.45%.These results demonstrate the effectiveness of our approach in detecting fraud in real-time and suggest that it can be a valuable tool for preventing fraud in telecommunications networks.

关键词： Telecom industry Streaming anomaly detection Fraud analysis Factorization machine Real-time system Security