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A multisource geomagnetic field model incorporating ocean circulation-induced magnetic field

Earth and Planetary Physics 2025年第3期9卷 550-563页

作者： HongBo Yao JuYuan Xu Cong Yang ZhengYong Ren Keke Zhang Macao Institute of Space Technology and Application Macao University of Science and TechnologyMacao 999078China School of Geosciences and Info-Physics Central South UniversityChangsha 410083China

The movement of global ocean circulation in the Earth’s main magnetic field generates a measurable induced magnetic field(about 2 nT at geomagnetic satellite altitudes).However,this ocean circulation-induced magnetic field has not been previously estimated or incorporated into geomagnetic field models,potentially causing leakage into the core field ***,we present a method to account for the circulation-induced magnetic field during geomagnetic field ***,a forward model of the circulation-induced magnetic field is constructed by numerically solving electromagnetic induction equations based on a realistic ocean circulation ***,this forward model is subtracted from the observed ***,the core and lithospheric fields,magnetospheric and Earth’s mantle-induced fields,and the ocean tide-induced magnetic field are *** our method to over 20 years of MSS-1,Swarm,CryoSat-2,and CHAMP satellite magnetic data,we derive a new multisource geomagnetic field model(MGFM).We find that incorporating a forward model of the circulation-induced magnetic field marginally improves the fit to the ***,we demonstrate that neglecting the circulation-induced magnetic field in geomagnetic field modeling results in leakage into the core field *** highlights of the MGFM model include:(i)a good agreement with the widely used CHAOS model series;(ii)the incorporation of magnetic fields induced by both ocean tides and circulation;and(iii)the suppression of leakage of the circulation-induced magnetic field into the core field model.

关键词： Macao science Satellite-1(MSS-1) geomagnetic field modeling ocean tides ocean circulation

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Phy-CoCo: Physical Constraint-Based Correlation Learning for Tropical Cyclone Intensity and Size Estimation 27

Phy-CoCo: Physical Constraint-Based Correlation Learning for...

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27th European Conference on Artificial Intelligence, ECAI 2024

作者： Yan, Hanting Mu, Pan Huang, Cheng Zhang, Jinglin Bai, Cong College of Computer Science Zhejiang University of Technology China School of Control Science and Engineering Shandong University China

ISBN: (纸本)9781643685489

Tropical Cyclone (TC) estimation aims to estimate various attributes of TC in real-time to alleviate and prevent disasters caused by violent TCs. As artificial intelligence technology advances, various deep learning-based multi-task estimation approaches have been proposed. However, most of them only focus on extracting common features of tasks, disregarding potential negative transfer and task interactions between different tasks. This paper is thus motivated to propose a Physical Constraint-based Correlation (Phy-CoCo) learning framework from the perspective of Multi-Task Learning (MTL). Specifically, for task-specific feature learning, we introduce Correlation Modeling (CoM) based on Centrally Expanded Pooling (CEP). Furthermore, for cross-task interaction, we propose a Multi-Domain Recurrent Convolution (MDRC) module to incorporate physical constraints into MTL. These physical constraints enable the transformation of different task features by simulating the physical relations among different attributes of TC. Lastly, in combination with a task-shared network that leverages the hybrid fusion of multi-modal data, our MTL framework accurately estimates various TC attributes. Extensive experiments conducted on our constructed dataset demonstrate that the proposed Phy-CoCo outperforms previous methods in TC estimation in terms of estimation error, verifying the potential of the physics-incorporated MTL model. © 2024 The Authors.

关键词： Tropical cyclone

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Functional Pattern-Related Anomaly Detection Approach Collaborating Binary Segmentation with Finite State Machine

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computers, Materials & Continua 2023年第12期77卷 3573-3592页

作者： Ming Wan Minglei Hao Jiawei Li Jiangyuan Yao Yan Song School of Information Liaoning UniversityShenyang110036China School of Computer Science and Technology Hainan UniversityHaikou570228China School of Physics Liaoning UniversityShenyang110036China

The process control-oriented threat,which can exploit OT(Operational technology)vulnerabilities to forcibly insert abnormal control commands or status information,has become one of the most devastating cyber attacks in industrial automation *** effectively detect this threat,this paper proposes one functional pattern-related anomaly detection approach,which skillfully collaborates the BinSeg(Binary Segmentation)algorithm with FSM(Finite State Machine)to identify anomalies between measuring data and control *** detecting the change points of measuring data,the BinSeg algorithm is introduced to generate some initial sequence segments,which can be further classified and merged into different functional patterns due to their backward difference means and *** analyzing the pattern association according to the Bayesian network,one functional state transition model based on FSM,which accurately describes the whole control and monitoring process,is constructed as one feasible detection ***,we use the typical SWaT(Secure Water Treatment)dataset to evaluate the proposed approach,and the experimental results show that:for one thing,compared with other change-point detection approaches,the BinSeg algorithm can be more suitable for the optimal sequence segmentation of measuring data due to its highest detection accuracy and least consuming time;for another,the proposed approach exhibits relatively excellent detection ability,because the average detection precision,recall rate and F1-score to identify 10 different attacks can reach 0.872,0.982 and 0.896,respectively.

关键词： Process control-oriented threat anomaly detection binary segmentation FSM

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Transferable Adversarial Facial Images for Privacy Protection 24

Transferable Adversarial Facial Images for Privacy Protectio...

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32nd ACM International Conference on Multimedia, MM 2024

作者： Li, Minghui Wang, Jiangxiong Zhang, Hao Zhou, Ziqi Hu, Shengshan Pei, Xiaobing Software Engineering Huazhong University of Science and Technology Wuhan China Computer Science and Technology Huazhong University of Science and Technology Wuhan China Cyber Science and Engineering Huazhong University of Science and Technology Wuhan China

ISBN: (纸本)9798400706868

The success of deep face recognition (FR) systems has raised serious privacy concerns due to their ability to enable unauthorized tracking of users in the digital world. Previous studies proposed introducing imperceptible adversarial noises into face images to deceive those face recognition models, thus achieving the goal of enhancing facial privacy protection. Nevertheless, they heavily rely on user-chosen references to guide the generation of adversarial noises, and cannot simultaneously construct natural and highly transferable adversarial face images in black-box scenarios. In light of this, we present a novel face privacy protection scheme with improved transferability while maintain high visual quality. We propose shaping the entire face space directly instead of exploiting one kind of facial characteristic like makeup information to integrate adversarial noises. To achieve this goal, we first exploit global adversarial latent search to traverse the latent space of the generative model, thereby creating natural adversarial face images with high transferability. We then introduce a key landmark regularization module to preserve the visual identity information. Finally, we investigate the impacts of various kinds of latent spaces and find that F latent space benefits the trade-off between visual naturalness and adversarial transferability. Extensive experiments over two datasets demonstrate that our approach significantly enhances attack transferability while maintaining high visual quality, outperforming state-of-the-art methods by an average 25% improvement in deep FR models and 10% improvement on commercial FR APIs. © 2024 ACM.

关键词： Differential privacy

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SEMDR: A Semantic-Aware Dual Encoder Model for Legal Judgment Prediction with Legal Clue Tracing

SEMDR: A Semantic-Aware Dual Encoder Model for Legal Judgmen...

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2024 IEEE International Conference on Systems, Man, and Cybernetics, SMC 2024

作者： Liu, Pengjie Zhang, Wang Ding, Yulong Zhang, Xuefeng Yang, Shuang-Hua College of Science Northeastern University China School of Computer Science and Engineering Southern University of Science and Technology China University of Reading Department of Computer Science United Kingdom

ISBN: (纸本)9781665410205

Legal Judgment Prediction (LJP) aims to form legal judgments based on the criminal fact description. However, researchers struggle to classify confusing criminal cases, such as robbery and theft, which requires LJP models to distinguish the nuances between similar crimes. Existing methods usually design handcrafted features to pick up necessary semantic legal clues to make more accurate legal judgment predictions. In this paper, we propose a Semantic-Aware Dual Encoder Model (SEMDR), which designs a novel legal clue tracing mechanism to conduct fine-grained semantic reasoning between criminal facts and instruments. Our legal clue tracing mechanism is built from three reasoning levels: 1) Lexicon-Tracing, which aims to extract criminal facts from criminal descriptions;2) Sentence Representation Learning, which contrastively trains language models to better represent confusing criminal facts;3) Multi-Fact Reasoning, which builds a reasons graph to propagate semantic clues among fact nodes to capture the subtle difference among criminal facts. Our legal clue tracing mechanism helps SEMDR achieve state-of-the-art on the CAIL2018 dataset and shows its advance in few-shot scenarios. Our experiments show that SEMDR has a strong ability to learn more uniform and distinguished representations for criminal facts, which helps to make more accurate predictions on confusing criminal cases and reduces the model uncertainty during making judgments. All codes will be released via GitHub. © 2024 IEEE.

关键词： Semantics

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Side Chain Crosslinked Anion Exchange Membrane for Acid Concentration by Electrodialysis

Chem and Bio Engineering

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Chem and Bio Engineering 2024年第7期1卷 647-657页

作者： He, Haoyang Chen, Qian Fu, Rongqiang Liu, Zhaoming Ge, Liang Xu, Tongwen Key Laboratory of Precision and Intelligent Chemistry School of Chemistry and Materials Science University of Science and Technology of China Hefei230026 China Applied Engineering Technology Research Center for Functional Membranes Institute of Advanced Technology University of Science and Technology of China Hefei230088 China Shandong Tianwei Membrane Technology Co. LTD Weifang262737 China

Electrodialysis (ED) technology for waste acid treatment has high economic efficiency and environmentally friendly advantages. The primary limitation of ED in the retrieval of low-concentration spent acids lies in the leakage of hydrogen ions through anion exchange membranes (AEMs) due to its extremely small size and high mobility. To address this issue, a series of AEMs named QPAB-x (x = 3, 5, 7, 10) were designed for acid concentration in ED process by increasing the membrane densities through in situ crosslinking in this study. The successful synthesis of polymers was confirmed through 1H nuclear magnetic resonance hydrogen (1H NMR) spectroscopy and Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy. Furthermore, ATR-FTIR spectroscopy showed that the higher the side chain content, the higher the crosslinking degree of the membranes. X-ray photoelectron spectroscopy (XPS) was employed to characterize the effects of aqueous and acidic environments on QPAB membranes. The performance disparities between QPAB-x membranes in acidic and aqueous environments were examined separately. Subsequently, the influence of crosslinking degree on the acid-blocking capability of the membranes was thoroughly investigated by conducting ED acid-concentration experiments to monitor the hydrogen ions concentration process and determine the current efficiency and energy consumption of the QPAB-x membranes. Our experimental results demonstrated that QPAB-x membranes with higher cross-linking degrees have lower water content, especially the QPAB-10 membrane with an IEC of approximately 1.5 mmol g-1 and a remarkably low water content of around 10%. This leads to a reduced H+ transfer number and excellent acid-blocking properties. Additionally, compared to commercial membrane A2, using the QPAB-10 membrane in the ED process resulted in a higher final H+ concentration in the concentrated chamber. Consequently, these synthesized membranes exhibit considerable promis

关键词： Fourier transform infrared spectroscopy

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Experiments and kinetic modeling of the sorbitol dehydration to isosorbide catalyzed by sulfuric acid under conditions of non-constant volume

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Chinese Journal of Chemical Engineering 2024年第9期73卷 281-289页

作者： Dechang Cheng Zhihong Ma Ziyang Liu Xiaohui Liu Tao Liu Weizhen Sun Ling Zhao State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Shanghai Key Laboratory of Functional Materials Chemistry Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Isosorbide is a novel bio-based material derived as a secondary dehydration product of *** work focuses on the kinetics of sulfuric acid-catalyzed dehydration of sorbitol under conditions of nonconstant ***,the effects of stirring rate,catalyst dosage,reaction temperature,and reaction time on the dehydration reaction of sorbitol were *** yield of isosorbide up to 77.13%was obtained after 1.5 h of reaction time under conditions of 2 kPa,1.0%(mass)catalyst dosage,and 413.15 *** on the sorbitol dehydration reaction mechanism and a simplified reaction network,a kinetic model was developed in this work.A good agreement was accomplished between kinetic modeling and experiments between 393.15 and 423.15 *** fitting results indicate that side reactions with higher activation energies are more affected by reaction temperatures,and the main side reaction that influences the selectivity of isosorbide is the oligomerization reaction among the primary dehydration products of *** model fitting of the catalyst amounts effect shows that the effective concentration of sulfuric acid would be reduced with the increase of dosage due to the molecular agglomeration ***,the kinetic experiments and modeling results obtained in this work will be helpful to the design and optimization of the industrial sorbitol dehydration process.

关键词： Isosorbide Sorbitol dehydration Non-constant volume Kinetic modeling

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Hyperbolic Sine Function-Based Full-State Feedback Attitude Tracking Control for Rigid Spacecraft

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IEEE Transactions on Systems, Man, and Cybernetics: Systems 2025年第5期55卷 3412-3424页

作者： Dong, Rui-Qi Wu, Ai-Guo Li, Bin Duan, Guang-Ren Department of Automation Shenzhen518055 China Sichuan University School of Aeronautics and Astronautics Chengdu610207 China Southern University of Science and Technology Center for Control Science and Technology Shenzhen518055 China Harbin Institute of Technology Center for Control Theory and Guidance Technology Harbin150001 China

The attitude tracking control with unwinding-free performance for rigid spacecraft is studied in this article. A full-state feedback control law based on a hyperbolic sine function is developed such that the resulted closed-loop system can achieve two stable equilibria. By Lyapunov stability theory and Barbalat's Lemma, it is proven that the obtained closed-loop system is almost globally asymptotically stable, and achieves unwinding-free performance. Further, by constructing a strict Lyapunov function, it is demonstrated that the two stable equilibria are exponentially stable. Moreover, subsets of attraction regions corresponding to each stable equilibrium are characterized. The simulation results illustrate that the proposed attitude control scheme can effectively avoid the unwinding problem during attitude tracking. © 2025 IEEE.

关键词： Lyapunov functions

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Achieving high strength in laser powder-bed fusion processed AlFeCuZr alloy via dual-nanoprecipitations and grain boundary segregation

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Journal of Materials science & technology 2023年第6期137卷 56-66页

作者： Jing-Yu Xu Cheng Zhang Li-Xue Liu Rong Guo Ming-Jun Sun Lin Liu School of Materials Science and Engineering State Key Lab for Materials Processing and Die&Mold TechnologyHuazhong University of Science and TechnologyWuhan 430074China

Additive manufacturing of aluminum alloys has received significant attention in the aerospace industry;however,achieving sufficient high strength,especially at elevated temperatures,remains ***,a crack-free and near-full dense Al-1Fe-0.6Cu-1.3Zr alloy was fabricated by the laser powder bed fusion(LPBF)*** Al-Fe-Cu-Zr alloy exhibits heterogeneous microstructures with two distinct *** is the so-called coarse-grain zones(CGZs)with an average grain size of 0.95μm,where(Al,Cu)Fe_(3) nanoparticles precipitate in the Al matrix and Fe and Cu cosegregate at the grain boundaries(GBs).The other is fine-grain zones(FGZs)with an average grain size of 0.45μm,where an Al 3 Zr nanoparti-cle precipitates in each of theα-Al grains(serves as the nuclei),and Fe-rich nanoprecipitates and Fe/Cu cosegregation appear at the *** a result,the LPBF Al-Fe-Cu-Zr alloy,with these unique heteroge-neous structures,displays high strength at both room temperature and elevated temperatures,e.g.,with high yield strengths of 500 MPa at room temperature,and 163 MPa at 573 K,both are higher than those of additive manufactured Al-based alloys reported thus *** is suggested that the high strength over a wide temperature range of the current LPBF Al alloy is mainly attributed to the combination of the precipitation strengthening mechanism and grain-boundary strengthening mechanism.

关键词： Laser powder bed fusion Aluminum alloy Heterogeneous microstructure Nanoprecipitation High strength

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Preparation and Thermal Properties of a Novel Modified Ammonium Alum/Expanded Graphite Composite Phase Change Material

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Journal of Thermal science 2023年第6期32卷 2093-2103页

作者： YIN Shaowu HAN Jiawei ZHANG Chao KANG Peng TONG Lige WANG Li School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of Energy Saving and Emission Reduction University of Science and Technology BeijingBeijing100083China

Thermal energy storage(TES)using phase change materials(PCMs)is a powerful solution to the improvement of energy *** application of Ammonium alum(A-alum,NH4Al(SO_(4))_(2)·12H_(2)O)in the latent thermal energy storage(LTES)systems is hampered due to its high supercooling and low thermal *** this work,modified A-alum(M-PCM)containing different nucleating agents was prepared and further adsorbed in expanded graphite(EG)to obtain composite phase change material(CPCM)to overcome the disadvantages of *** properties,thermal cycle stability,microstructure and chemical compatibility of CPCM were characterized by differential scanning calorimetry,thermal constant analysis,scanning electron microscopy,X-ray diffraction and Fourier transform infrared *** cold rewarming phenomenon of CPCM was established and *** showed that the latent heat and melting point of CPCM were 187.22 J/g and 91.54℃,*** supercooling of CPCM decreased by 9.61℃,and thermal conductivity increased by 27 times compared with pure *** storage and release tests indicated that 2 wt%calcium chloride dihydrate(CCD,CaCl_(2)·2H_(2)O)was the optimum nucleating agent for *** result of TG and 30 thermal cycles revealed that CPCM exhibited favorable thermal stability and reliability during the operating *** prepared modified A-alum/EG CPCM has a promising application prospect for LTES.

关键词： composite phase change material thermal property ammonium alum expanded graphite supercooling thermal conductivity

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