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Science China(Information Sciences) 2025年第1期68卷 292-305页

作者： Tao shi Wei-Wei CHE School of Mechatronic Engineering and Automation Shanghai University State Key Laboratory of Synthetical Automation for Process Industries Northeastern University College of Information Science and Engineering Northeastern University

This article proposes a distributed dynamic event-triggered data-driven iterative learning control(DET-DDILC)scheme under a predefined performance to tackle the bipartite tracking control problem for multiagent systems(MASs). An improved dynamic linearization technique is utilized to convert the nonlinear MASs into an iterative linear data model. First,a peer-to-peer mapping function is introduced to map the constrained distributed system output homeomorphism to an unconstrained one. In addition, a DET mechanism based on a time-iteration-varying function is devised to conserve network communication resources. Based on the unconstrained transformation and the designed DET mechanism, the DET-DDILC algorithm is devised to ensure that the bipartite tracking performance of MASs can be within the preset range. Finally, the effectiveness and feasibility of the designed control scheme are demonstrated via a simulation case by a comparison.

关键词： bipartite tracking control prescribed performance event-triggered iterative learning control multiagent systems

Penalty Function-Based Distributed Primal-Dual Algorithm for Nonconvex Optimization Problem

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 394-402页

作者： Xiasheng shi Changyin Sun IEEE the Engineering Research Center of Autonomous Unmanned System Technology Ministry of Education Anhui University the School of Artificial Intelligence Anhui University Anhui Provincial Engineering Research Center for Unmanned System and Intelligent Technology Anhui University the Anhui Key Laboratory Industrial Energy-Saving and Safety Anhui University

This paper addresses the distributed nonconvex optimization problem, where both the global cost function and local inequality constraint function are nonconvex. To tackle this issue, the p-power transformation and penalty function techniques are introduced to reframe the nonconvex optimization problem. This ensures that the Hessian matrix of the augmented Lagrangian function becomes local positive definite by choosing appropriate control parameters. A multi-timescale primal-dual method is then devised based on the Karush-Kuhn-Tucker(KKT) point of the reformulated nonconvex problem to attain convergence. The Lyapunov theory guarantees the model's stability in the presence of an undirected and connected communication network. Finally, two nonconvex optimization problems are presented to demonstrate the efficacy of the previously developed method.

关键词： Constrained optimization Karush-Kuhn-Tucker (KKT) point nonconvex p-power transformation

Accelerating homogenization kinetics and enhancing hot-workability of as-cast nickel-based superalloy via prior hot-deformation

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Journal of Iron and Steel Research International 2025年第1期32卷 215-226页

作者： Jia-jun Chen Yang Zhou Hao-ran Han Xian-guang Zhang Goro Miyamoto Ping-mei Tang Dong-ping Xiao Jian-hui Fu Peng shi Yi-wu Pei Jian Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Chengdu Advanced Metal Materials Industrial Technology Institute Co. Ltd.Chengdu 610300SichuanChina Institute for Materials Research Tohoku UniversitySendai 980-8577Aoba-KuJapan

Enhancing homogenization efficiency and hot-workability is the key issue for wrought superalloys in the industry.A novel approach for simultaneous accelerating the homogenization kinetics and improving hot-workability via a simple way of prior hot-deformation was proposed,which was not widely accepted for wrought *** homogenization efficiency is increased by 40%-70%via performing 10%-20%prior *** theoretical and experimental analyses revealed that the increment in homogenization efficiency is mainly attributed to the decrease in interdendritic-segregation spacing,and thus the necessary diffusion distance,rather than that of *** addition,dynamic and static recrystallizations occurred during the prior hot-deformation and diffusion-annealing processes,and the grains were significantly refined even after the ***,the size of the precipitates was refined as *** enhanced the hot-workability of the homogenized ingot for the subsequent cogging process.

关键词： Nickel-based superalloy Homogenization kinetics Prior hot-deformation Grain size Hot workability

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基于动力学系统移动焊接机器人焊缝跟踪控制

系统仿真学报 2009年第21期21卷 6803-6806页

作者：张庭李慨戴士杰肖淑梅黄鹤河北工业大学机械工程学院天津300130

为了解决轮式移动焊接机器人的焊缝跟踪问题,从移动焊接机器人的运动学和动力学模型出发,采用分段运动学到动力学的方法设计焊缝跟踪控制器。控制算法结合积分Backstepping算法和单层神经元网络控制算法,利用单层神经元网络的自学习和... 详细信息

为了解决轮式移动焊接机器人的焊缝跟踪问题,从移动焊接机器人的运动学和动力学模型出发,采用分段运动学到动力学的方法设计焊缝跟踪控制器。控制算法结合积分Backstepping算法和单层神经元网络控制算法,利用单层神经元网络的自学习和自适应能力克服机器人模型参数部分未知和扰动的影响,使跟踪更加快速、平滑。在选定系统Lyapunov函数基础上,证明了所选取的控制力矩输入使系统全局渐进稳定。经MATLAB仿真验证了该控制算法的有效性。

关键词：移动焊接机器人焊缝跟踪积分Backstepping方法神经网络 Lyapunov函数

降钙素及二膦酸盐治疗血液透析患者肾性骨病的长期疗效

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中华肾脏病杂志 2009年第5期25卷 341-344页

作者：石书梅赵学智陆烈卜磊陈意志上海长征医院肾内科 200003

目的观察降钙素及二膦酸盐治疗维持性血液透析（MHD）患者肾性骨病的疗效及安全性。方法43例MHD患者按数字随机法分成A、B两组，均常规服用碳酸钙1．0gtid、骨化三醇0．25μg qd。A组加用降钙素20u，皮下注射，每周3次（常规血液透析时... 详细信息

目的观察降钙素及二膦酸盐治疗维持性血液透析（MHD）患者肾性骨病的疗效及安全性。方法43例MHD患者按数字随机法分成A、B两组，均常规服用碳酸钙1．0gtid、骨化三醇0．25μg qd。A组加用降钙素20u，皮下注射，每周3次（常规血液透析时使用）；B组在使用降钙素的同时加用二膦酸盐70mg，口服，每周1次。在治疗前及治疗3、6、12个月时分别检测血全段甲状旁腺激素（PTH）、血钙、血磷、血清碱性磷酸酶（AKP）水平和腰椎、股骨颈骨密度，以及记录骨痛程度（采用视觉模拟疼痛评分，VAS）和不良反应。结果两组患者AKP和PTH水平比治疗前显著下降，治疗前和12个月时，A组AKP（U／L）为244．05±41．99和148．35±27．7l；B组为245．60±40．86和143．40±28．03；A组PTH（ng／L）为697．5±119．7和267．4±45．9；B组为708．2±120．3和277．6±41．9；差异均有统计学意义（均P〈0．05）。两组血钙、血磷水平治疗前后差异无统计学意义。两组患者腰椎、股骨颈骨密度在治疗3、6个月时变化不明显，12个月时显著好转。与治疗前比较，12个月时A组腰椎骨密度（g／cm^2）为1．202±0．251比1．062±0．223；B组为1．189±0．225比1．033±0．152；A组股骨颈骨密度（g／cm^2）为1．067±0．095比0．993±0．108；B组为1．018±0．217比0．947＋0．083，均P〈0．05。两组治疗前后主观评价骨痛程度减轻，VAS比治疗前显著下降，差异均有统计学意义（P〈0．05）。除B组个别患者有轻度消化道反应外，余无不良反应。结论降钙素及合用二膦酸盐可有效减少MHD患者的骨量丢失，降低PTH水平，改善临床症状，且无明显不良反应。单用降钙素与合用二膦酸盐的疗效无显著差异。

关键词：血液透析滤过骨病医学骨密度降钙素二膦酸盐

内皮型一氧化氮合酶基因敲除小鼠心肌细胞对苯福林诱导的过度增殖反应

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中国组织工程研究与临床康复 2008年第15期12卷 2922-2925页

作者：石姝梅徐刚吴华碧陆建林顺德职业技术学院医学系广东省佛山市528300

目的：通过RNA定量检测和细胞面积测定两种方法，观察内皮型一氧化氮合酶基因敲除与野生型新生小鼠的离体心肌细胞对心肌肥大诱导因子反应性的差异。方法：实验于2007-08在顺德职业技术学院医学系实验研究中心完成。①实验材料：出生1～... 详细信息

目的：通过RNA定量检测和细胞面积测定两种方法，观察内皮型一氧化氮合酶基因敲除与野生型新生小鼠的离体心肌细胞对心肌肥大诱导因子反应性的差异。方法：实验于2007-08在顺德职业技术学院医学系实验研究中心完成。①实验材料：出生1～3d C57BL／6品系内皮型一氧化氮合酶基因敲除小鼠和野生型小鼠，雌雄不拘。②实验方法：对小鼠心肌细胞及成纤维细胞进行培养，72h后分为实验组和对照组，将肾上腺素能受体激动剂苯福林掺入培养心肌细胞，另设空白对照组：在基础培养液中加入与实验组等量的DMEM。③实验评估：采用DNA、RNA定量检测、细胞面积测定方法，在细胞水平观察内皮型一氧化氮合酶基因敲除小鼠和野生型小鼠心肌细胞增殖、肥大反应之间的差异。结果：①培养的心肌细胞在加入苯福林72h后于显微镜下观察两组细胞均呈椭圆形、长菱形。②与对照组相比，实验组心肌细胞与成纤维细胞RNA检测及荧光值均增高（P〈0．05）；空白对照组心肌细胞与成纤维细胞RNA检测荧光值均较实验组和对照组低（P〈0．05）。③与空白对照组相比，实验组和对照组心肌细胞与成纤维细胞面积荧光值均增高（P〈0．05）；其中实验组心肌细胞面积荧光值较对照组高（P〈0．05）。结论：内皮型一氧化氮合酶基因敲除小鼠其离体心肌细胞在心肌肥大诱导因子刺激下产生过度增殖反应。

关键词：内皮型一氧化氮合酶心肌细胞培养小鼠肥大组织构建

Catalytic atroposelective synthesis of indolyl quinazolinones bearing N-N/C-C diaxes

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Science China Chemistry 2025年

作者： Ning-Yi Wang shuo Gao Zhu-Di shu Bei-Bei Cheng Chun Ma Yu-Chen Zhang Feng shi Research Center of Chiral Functional Heterocycles School of Chemistry and Materials Science Jiangsu Normal University School of Petrochemical Engineering Changzhou University School of Chemistry and Chemical Engineering Henan Normal University

The first catalytic atroposelective synthesis of indole derivatives bearing N-N/C-C diaxes has been established by the strategy of de novo ring formation. By this strategy, various indolyl quinazolinones bearing vicinal N-N/C-C diaxes were synthesized in high yields with overall good diastereoselectivities and excellent enantioselectivities via chiral phosphoric acid-catalyzed onepot asymmetric formal (5+1) cycloaddition/oxidation reaction. Moreover, such indolyl quinazolinones bearing vicinal N-N/CC diaxes have good configurational stability and could be converted into new chiral ligands with applications in asymmetric catalysis. Therefore, this work not only offered a new member for the family of diaxial atropisomers, but also provided a powerful strategy for catalytic asymmetric synthesis of atropisomers bearing N-N/C-C diaxes.

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Calibration of the Solar X-ray Detector on-board the Macao Science Satellite-1B for Soft X-ray Detection

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Science China Earth Sciences 2025年第1期68卷 11-26页

作者： Man-Hei NG Xiaoping ZHANG Jianwu CHEN Yongqiang shi Fuchang ZUO Wenxi PENG Weichun FU Liansheng LI Pengwei LUO Chi-Long TANG Guozheng ZHANG Zhiwu mei Li WANG Cunhui LI Jiaming OU Yanyan Xu State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao999078China Space Optoelectronic Measurement and Perception Laboratory Beijing Institute of Control EngineeringBeijing100190China Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of PhysicsLanzhou730000China China National Space Administration(CNSA) Macao Center for Space Exploration and ScienceMacao999078China

The Solar X-ray Detector(SXD)on-board the Macao Science Satellite-1B(MSS-1B)was successfully launched via the Chinese Long March-2C rocket on 21 May 2023,and commenced operations in early June of the same *** MSS-1B/Soft X-ray Detection Units(SXDUs)employ two silicon drift detectors(SDDs),providing a wide range of energy spectra spanning from 0.7 to 24 ***,the SXDUs deliver a high-resolution capability of 0.14 keV@5.9 keV and operate with a time cadence of 1 ***,we perform thorough calibrations of the MSS-1B/SXDUs,employing a combination of ground experiments and *** addition,quantitative analysis comparing the flux measurements obtained by the MSS-1B/SXDUs to the data collected by the Geostationary Operational Environmental Satellite(GOES),provides compelling evidence of their ***,the preliminary spectral analysis results showcase the robustness and expected performance of the MSS-1B/SXDUs,unlocking their potential for facilitating the study of dynamic evolution of solar ***,the innovative MSS-1B/Solar X-ray Detector facilitates concurrent observations of solar soft and hard X-rays,thereby making valuable contributions to the advancements in solar research.

关键词： Macao Science Satellite-1B(MSS-1B) Calibration Solar X-Ray Detector Spectrometer Soft X-rays Solar flares Solar abundances

Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction

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Computers, Materials & Continua 2025年第1期82卷 1069-1086页

作者： shi Li Didi Sun College of Computer and Control Engineering Northeast Forestry UniversityHarbin150040China

With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant ***-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying *** comprehension is crucial for making informed strategic decisions in various business and societal ***,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause *** address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment *** model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause ***,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among *** proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 *** results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its *** research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-c

关键词： Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms

Detection and Recognition of Spray Code Numbers on Can Surfaces Based on OCR

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Computers, Materials & Continua 2025年第1期82卷 1109-1128页

作者： Hailong Wang Junchao shi School of Computer Science Zhongyuan University of TechnologyZhengzhou450007China

A two-stage algorithm based on deep learning for the detection and recognition of can bottom spray codes and numbers is proposed to address the problems of small character areas and fast production line speeds in can bottom spray code number *** the coding number detection stage,Differentiable Binarization Network is used as the backbone network,combined with the Attention and Dilation Convolutions Path Aggregation Network feature fusion structure to enhance the model detection *** terms of text recognition,using the Scene Visual Text Recognition coding number recognition network for end-to-end training can alleviate the problem of coding recognition errors caused by image color distortion due to variations in lighting and background *** addition,model pruning and quantization are used to reduce the number ofmodel parameters to meet deployment requirements in resource-constrained environments.A comparative experiment was conducted using the dataset of tank bottom spray code numbers collected on-site,and a transfer experiment was conducted using the dataset of packaging box production *** experimental results show that the algorithm proposed in this study can effectively locate the coding of cans at different positions on the roller conveyor,and can accurately identify the coding numbers at high production line *** Hmean value of the coding number detection is 97.32%,and the accuracy of the coding number recognition is 98.21%.This verifies that the algorithm proposed in this paper has high accuracy in coding number detection and recognition.

关键词： Can coding recognition differentiable binarization network scene visual text recognition model pruning and quantification transport model