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Precision motion control for electro-hydraulic axis systems under unknown time-variant parameters and disturbances

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Chinese Journal of Aeronautics 2024年第1期37卷 463-471页

作者： Xiaowei YANG Yaowen GE Wenxiang deng Jianyong YAO School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

This article focuses on asymptotic precision motion control for electro-hydraulic axis systems under unknown time-variant parameters,mismatched and matched *** from the traditional adaptive results that are applied to dispose of unknown constant parameters only,the unique feature is that an adaptive-gain nonlinear term is introduced into the control design to handle unknown time-variant *** both mismatched and matched disturbances existing in electro-hydraulic axis systems can also be addressed in this *** skillful integration of the backstepping technique and the adaptive control,a synthesized controller framework is successfully developed for electro-hydraulic axis systems,in which the coupled interaction between parameter estimation and disturbance estimation is ***,this designed controller has the capacity of low-computation costs and simpler parameter tuning when compared to the other ones that integrate the adaptive control and observer/estimator-based technique to dividually handle parameter uncertainties and ***,a nonlinear filter is designed to eliminate the“explosion of complexity”issue existing in the classical back-stepping *** stability analysis uncovers that all the closed-loop signals are bounded and the asymptotic tracking performance is also ***,contrastive experiment results validate the superiority of the developed method as well.

关键词： Adaptive control Asymptotic convergence Electro-hydraulic axis system Precision motion control Unknown time-variant parameters and disturbances

Disinfection Byproducts and Their Precursors in Drinking Water Sources:Origins,Influencing Factors,and Environmental Insights

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Engineering 2024年第5期36卷 36-50页

作者： Rong Xiao Yang deng Zuxin Xu Wenhai Chu State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Ministry of Education Key Laboratory of the Yangtze River Water Environment Tongji UniversityShanghai 200092China Department of Earth and Environmental Studies Montclair State UniversityMontclairNJ 07043USA

Tracing the contamination origins in water sources and identifying the impacts of natural and human processes are essential for ecological safety and public ***,current analysis approaches are not ideal,as they tend to be laborious,time-consuming,or technically *** byproducts(DBPs)are a family of well-known secondary pollutants formed by the reactions of chemical disinfectants with DBP precursors during water disinfection *** DBP precursors have various origins(e.g.,natural,domestic,industrial,and agricultural sources),and since the formation of DBPs from different precursors in the presence of specific disinfectants is distinctive,we argue that DBPs and DBP precursors can serve as alternative indicators to assess the contamination in water sources and identify pollution *** providing a retrospective of the origins of DBPs and DBP precursors,as well as the specific formation patterns of DBPs from different precursors,this article presents an overview of the impacts of various natural and anthropogenic factors on DBPs and DBP precursors in drinking water *** practice,the DBPs(i.e.,their concentration and speciation)originally present in source water and the DBP precursors determined using DBP formation potential tests—in which water samples are dosed with a stoichiometric excess of specific disinfectants in order to maximize DBP formation under certain reaction conditions—can be considered as alternative *** jointly used with other water quality parameters(e.g.,dissolved organic carbon,dissolved organic nitrogen,fluorescence,and molecular weight distribution)and specific contaminants of emerging concern(e.g.,certain pharmaceuticals and personal care products),DBPs and DBP precursors in drinking water sources can provide a more comprehensive picture of water pollution for better managing water resources and ensuring human health.

关键词： Disinfection byproducts Disinfection byproduct precursors Drinking water sources Contamination indicator Natural factors Human factors

A new centrality measure based on neighbor loop structure for network dismantling

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Digital Communications and Networks 2024年第2期10卷 472-480页

作者： Qingxia Liu Bang Wang Jiming Qi Xianjun deng School of Electronic Information and Communications Huazhong University of Science and TechnologyWuhan430074China School of Cyber Science and Engineering Huazhong University of Science and TechnologyWuhan430074China

Nearly all real-world networks are complex networks and usually are in danger of ***,it is crucial to exploit and understand the mechanisms of network attacks and provide better protection for network *** dismantling aims to find the smallest set of nodes such that after their removal the network is broken into connected components of sub-extensive *** overcome the limitations and drawbacks of existing network dismantling methods,this paper focuses on network dismantling problem and proposes a neighbor-loop structure based centrality metric,NL,which achieves a balance between computational efficiency and evaluation *** addition,we design a novel method combining NL-based nodes-removing,greedy tree-breaking and ***,we compare five baseline methods with our algorithm on ten widely used real-world networks and three types of model networks including Erd€os-Renyi random networks,Watts-Strogatz smallworld networks and Barabasi-Albert scale-free networks with different network generation *** results demonstrate that our proposed method outperforms most peer methods by obtaining a minimal set of targeted attack ***,the insights gained from this study may be of assistance to future practical research into real-world networks.

关键词： Complex networks Network dismantling Centrality measure

Constructions of optimal binary locally repairable codes via intersection subspaces

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Science China(Information Sciences) 2024年第6期67卷 418-432页

作者： Wenqin ZHANG deng TANG Chenhao YING Yuan LUO School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University

Locally repairable codes（LRCs）, which can recover any symbol of a codeword by reading only a small number of other symbols, have been widely used in real-world distributed storage systems, such as Microsoft Azure Storage and Ceph Storage Cluster. Since binary linear LRCs can significantly reduce coding and decoding complexity, constructions of binary LRCs are of particular interest. The aim of this paper is to construct dimensional optimal binary LRCs with disjoint local repair groups. We introduce a method to connect intersection subspaces with binary LRCs and construct dimensional optimal binary linear LRCs with locality 2b（b 3） and minimum distance d 6 by employing intersection subspaces deduced from the direct sum. This method will sufficiently increase the number of possible repair groups of dimensional optimal LRCs, thus efficiently expanding the range of the construction parameters while keeping the largest code rates compared with all known binary linear LRCs with minimum distance d 6 and locality 2b.

关键词： locally repairable codes disjoint local repair groups distributed storage systems intersection subspaces direct sum

压力-应变环评价左束支不同起搏模式对左室心肌做功的影响

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中华超声影像学杂志 2022年第9期31卷 753-758页

作者：王培伟陈样新杨莉郑韶欣邓冰清邱琼中山大学孙逸仙纪念医院心血管内科广州510120

目的利用压力-应变环技术评价左束支起搏下不同起搏模式(单/双极)对心室机械同步性及心肌做功的影响。方法选取2018年12月至2020年7月因症状性心动过缓于中山大学孙逸仙纪念医院行左束支起搏(LBBP)的患者29例为LBBP组,以同期基线条件相... 详细信息

目的利用压力-应变环技术评价左束支起搏下不同起搏模式(单/双极)对心室机械同步性及心肌做功的影响。方法选取2018年12月至2020年7月因症状性心动过缓于中山大学孙逸仙纪念医院行左束支起搏(LBBP)的患者29例为LBBP组,以同期基线条件相匹配的29例右心室起搏(RVP)患者作为RVP组。所有LBBP患者术后1周内分别程控为单极、双极起搏模式,评价心室间及左室内的机械同步性,并应用左室压力-应变环技术获得整体做功指数(GWI)、整体有效功(GCW)、整体无用功(GWW)和整体做功效率(GWE)。比较LBBP组与RVP组之间、LBBP组内不同起搏模式下的心脏机械同步性和心肌做功。结果与RVP组相比,LBBP组室内及室间机械同步性显著改善(均P0.05),并且提高输出电压后上述参数差异仍无统计学意义(均P>0.05)。结论与RVP患者相比,LBBP患者能保持更好的机械同步性,心肌做功效率更高;LBBP不同起搏模式对心室机械同步性及心肌做功效率无影响。

关键词：超声心动描记术左束支起搏压力-应变环心肌做功机械同步性

Superhydrophobic Surface-Assisted Preparation of Microspheres and Supraparticles and Their Applications

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Nano-Micro Letters 2024年第4期16卷 110-138页

作者： Mengyao Pan Huijuan Shao Yue Fan Jinlong Yang Jiaxin Liu Zhongqian deng Zhenda Liu Zhidi Chen Jun Zhang Kangfeng Yi Yucai Su Dehui Wang Xu deng Fei deng Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 611731People’s Republic of China School of Materials Science and Engineering Sun Yat-Sen UniversityGuangzhou 510275People’s Republic of China Shenzhen Institute for Advanced Study University of Electronic Science and Technology of ChinaShenzhen 518110People’s Republic of China Pharmaceutical Glass Co.Ltd Zibo 256100People’s Republic of China Department of Nephropathy School of MedicineSichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengduPeople’s Republic of China Department of Nephrology Sichuan Provincial People’s Hospital Jinniu HospitalChengdu Jinniu District People’s HospitalChengduPeople’s Republic of China

Superhydrophobic surface(SHS) has been well developed, as SHS renders the property of minimizing the water/solid contact interface. Water droplets deposited onto SHS with contact angles exceeding 150°, allow them to retain spherical shapes, and the low adhesion of SHS facilitates easy droplet collection when tilting the substrate. These characteristics make SHS suitable for a wide range of applications. One particularly promising application is the fabrication of microsphere and supraparticle materials. SHS offers a distinct advantage as a universal platform capable of providing customized services for a variety of microspheres and supraparticles. In this review, an overview of the strategies for fabricating microspheres and supraparticles with the aid of SHS, including cross-linking process, polymer melting,and droplet template evaporation methods, is first presented. Then, the applications of microspheres and supraparticles formed onto SHS are discussed in detail, for example, fabricating photonic devices with controllable structures and tunable structural colors, acting as catalysts with emerging or synergetic properties, being integrated into the biomedical field to construct the devices with different medicinal purposes, being utilized for inducing protein crystallization and detecting trace amounts of analytes. Finally,the perspective on future developments involved with this research field is given, along with some obstacles and opportunities.

关键词： Superhydrophobic surface Microspheres and supraparticles Photonic devices Catalysts Biomedical and trace detections

Multimodal Sentiment Analysis Based on a Cross-Modal Multihead Attention Mechanism

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Computers, Materials & Continua 2024年第1期78卷 1157-1170页

作者： Lujuan deng Boyi Liu Zuhe Li School of Computer and Communication Engineering Zhengzhou University of Light IndustryZhengzhou450002China

Multimodal sentiment analysis aims to understand people’s emotions and opinions from diverse ***-nating or multiplying various modalities is a traditional multi-modal sentiment analysis fusion *** fusion method does not utilize the correlation information between *** solve this problem,this paper proposes amodel based on amulti-head attention ***,after preprocessing the original ***,the feature representation is converted into a sequence of word vectors and positional encoding is introduced to better understand the semantic and sequential information in the input ***,the input coding sequence is fed into the transformer model for further processing and *** the transformer layer,a cross-modal attention consisting of a pair of multi-head attention modules is employed to reflect the correlation between ***,the processed results are input into the feedforward neural network to obtain the emotional output through the classification *** the above processing flow,the model can capture semantic information and contextual relationships and achieve good results in various natural language processing *** model was tested on the CMU Multimodal Opinion Sentiment and Emotion Intensity(CMU-MOSEI)and Multimodal EmotionLines Dataset(MELD),achieving an accuracy of 82.04% and F1 parameters reached 80.59% on the former dataset.

关键词： Emotion analysis deep learning cross-modal attention mechanism

The synthetic gauge field and exotic vortex phase with spin-orbital-angular-momentum coupling

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Communications in Theoretical Physics 2024年第8期76卷 52-59页

作者： Yingqi Liu Yun Chen Yuangang deng Guangdong Provincial Key Laboratory of Quantum Metrology and Sensing&School of Physics and Astronomy Sun Yat-Sen University(Zhuhai Campus)Zhuhai 519082China

Ultracold atoms endowed with tunable spin-orbital-angular-momentum coupling(SOAMC)represent a promising avenue for delving into exotic quantum phenomena. Building on recent experimental advancements, we propose the generation of synthetic gauge fields, and by including exotic vortex phases within spinor Bose-Einstein condensates, employing a combination of a running wave and Laguerre-Gaussian laser fields. We investigate the ground-state characteristics of the SOAMC condensate, revealing the emergence of exotic vortex states with controllable orbital angular momenta. It is shown that the interplay of the SOAMC and conventional spin-linear-momentum coupling induced by the running wave beam leads to the formation of a vortex state exhibiting a phase stripe hosting single multiply quantized singularity. The phase of the ground state will undergo the phase transition corresponding to the breaking of rotational symmetry while preserving the mirror symmetry. Importantly, the observed density distribution of the ground-state wavefunction, exhibiting broken rotational symmetry, can be well characterized by the synthetic magnetic field generated through light interaction with the dressed spin state. Our findings pave the way for further exploration into the rotational properties of stable exotic vortices with higher orbital angular momenta against splitting in the presence of synthetic gauge fields in ultracold quantum gases.

关键词： ultracold atoms synthetic gauge fields vortex phases spin-orbital-angularmomentum coupling

Advancements in Remote Sensing Image Dehazing: Introducing URA-Net with Multi-Scale Dense Feature Fusion Clusters and Gated Jump Connection

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2397-2424页

作者： Hongchi Liu Xing deng Haijian Shao School of Computer Jiangsu University of Science and TechnologyZhenjiang212003China Department of Electrical and Computer Engineering University of NevadaLas Vegas89119USA

The degradation of optical remote sensing images due to atmospheric haze poses a significant obstacle,profoundly impeding their effective utilization across various *** methodologies have emerged as pivotal components of image preprocessing,fostering an improvement in the quality of remote sensing *** enhancement renders remote sensing data more indispensable,thereby enhancing the accuracy of target *** defogging techniques based on simplistic atmospheric degradation models have proven inadequate for mitigating non-uniform haze within remotely sensed *** response to this challenge,a novel UNet Residual Attention Network(URA-Net)is *** paradigmatic approach materializes as an end-to-end convolutional neural network distinguished by its utilization of multi-scale dense feature fusion clusters and gated jump *** essence of our methodology lies in local feature fusion within dense residual clusters,enabling the extraction of pertinent features from both preceding and current local data,depending on contextual *** intelligently orchestrated gated structures facilitate the propagation of these features to the decoder,resulting in superior outcomes in haze *** validation through a plethora of experiments substantiates the efficacy of URA-Net,demonstrating its superior performance compared to existing methods when applied to established datasets for remote sensing image *** the RICE-1 dataset,URA-Net achieves a Peak Signal-to-Noise Ratio(PSNR)of 29.07 dB,surpassing the Dark Channel Prior(DCP)by 11.17 dB,the All-in-One Network for Dehazing(AOD)by 7.82 dB,the Optimal Transmission Map and Adaptive Atmospheric Light For Dehazing(OTM-AAL)by 5.37 dB,the Unsupervised Single Image Dehazing(USID)by 8.0 dB,and the Superpixel-based Remote Sensing Image Dehazing(SRD)by 8.5 *** noteworthy,on the SateHaze1k dataset,URA-Net attains preeminence in overall performance,yieldi

关键词： Remote sensing image image dehazing deep learning feature fusion