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Distributed Adaptive Cooperative Tracking of Uncertain Nonlinear Fractional-order Multi-agent Systems

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IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 292-300页

作者： Zhitao Li lixin Gao Wenhai Chen Yu xu Institute of Intelligent Systems and Decision Wenzhou UniversityZhejiang 325035China College of Physics and Electronic Information Engineering Wenzhou UniversityWenzhou 325035China

In this paper, the leader-following tracking problem of fractional-order multi-agent systems is addressed. The dynamics of each agent may be heterogeneous and has unknown nonlinearities. By assumptions that the interaction topology is undirected and connected and the unknown nonlinear uncertain dynamics can be parameterized by a neural network, an adaptive learning law is proposed to deal with unknown nonlinear dynamics, based on which a kind of cooperative tracking protocols are constructed. The feedback gain matrix is obtained to solve an algebraic Riccati equation. To construct the fully distributed cooperative tracking protocols, the adaptive law is also adopted to adjust the coupling weight. With the developed control laws,we can prove that all signals in the closed-loop systems are guaranteed to be uniformly ultimately bounded. Finally, a simple simulation example is provided to illustrate the established result.

关键词： Index Terms—Adaptive control consensus distributed control,fractional-order systems multi-agent system.

Suboptimal adaptive tracking control for FIR systems with binary-valued observations

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Science China(Information Sciences) 2021年第7期64卷 37-47页

作者： Xiangquan LI Zhengguang xu Jiarui CUI lixin ZHANG School of Automation and Electrical Engineering University of Science and Technology Beijing Key Laboratory of Knowledge Automation for Industrial Processes Ministry of Education

In this paper, we investigate and analyze the suboptimal adaptive control for finite impulse response(FIR) systems with binary-valued observations. As the parameters of FIR systems are unknown and the measurable observations can only provide limited information, we propose and analyze a two-segment design method of an adaptive control law. First, we divide the system running time axis into many sections;each of these sections is divided into two segments. During the short segment, we design the system inputs for estimating parameters. Thus, we employ the empirical-measure-based technique for designing the identification algorithm. Second, we introduce a tracking control law to track a given target based on the system parameter estimates obtained in the short segment. We achieve this using the certainty equivalent principle in the long segment. As the length of short segments tends to infinity, we observe that the parameter estimation algorithm is consistent. However, when the length of segments tends to infinity, we find that the adaptive tracking control law is asymptotically suboptimal. Finally, we demonstrate the efficiency of the two-segment design method using the simulation results.

关键词： parameter identification FIR systems binary-valued observations asymptotically suboptimal tracking adaptive control

Concentration of mixed acid by electrodialysis for the intensification of absorption process in acrylic acid production

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Chinese Journal of Chemical Engineering 2021年第8期34卷 10-18页

作者： Hanxiao Du lixin Xie Jie Liu Shichang xu School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Membrane Science and Desalination Technology State Key Laboratory of Chemical EngineeringTianjin UniversityTianjin 300072China School of Chemical Engineering and Technology Hebei University of TechnologyTianjin 300130China Engineering Research Center of Seawater Utilization Ministry of EducationTianjin 300130China

The absorption process in acrylic acid production was water-intensive.The concentration of acrylic acid before distillation process was low,which induced to large amount of wastewater and enormous energy consumption.In this work,a new method was proposed to concentrate the side stream of absorption column and thus increase the concentration in bottom product by electrodialysis.The influence of operating conditions on concentration rate and specific energy consumption were investigated by a laboratory-scale device.When the voltage drop was 1 V·cP^(-1)(1 cP=10^(-3) Pa·s),flow velocity was 3 cm·s^(-1) and the temperature was 35℃,the concentration rates of acrylic acid and acetic acid could be 203.3%and 156.6%in the continual-ED process.Based on the experimental data,the absorption process combined with ED was simulated,in which the diluted solution from ED process was used as spray water and the concentrated solution was feed back to the absorption column.The results shown that the flow rate of spray water was decreased by 37.1%,and the acrylic acid concentration at the bottom of the tower was increased by 4.56%.The ions exchange membranes before and after use 1200 h were tested by membrane surface morphology(scanning electron microscope),membrane chemical groups(infrared spectra),ion exchange capacity,and membrane area resistance,which indicated the membrane were stable in the acid system.This method provides new method for energy conservation and emission reduction in the traditional chemical industry.

关键词： Acrylic acid production Electrodialysis Concentration Membranes Absorption Mixtures

基于铁死亡角度筛选治疗肝纤维化的天然药物成分

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今日药学 2024年第4期34卷 268-274页

作者：徐达陈琪杨立新王佳慧汪磊赵铁建郑洋广西中医药大学赛恩斯新医药学院广西南宁530222

目的借助生物信息学研究方法从铁死亡角度筛选治疗肝纤维化的天然药物活性成分,为治疗慢性肝病开辟新视野。方法在GEO数据库中检索与肝纤维化相关的数据集,在FerrDb数据库收集与铁死亡相关靶点。将铁死亡与肝纤维化差异表达的交互靶... 详细信息

目的借助生物信息学研究方法从铁死亡角度筛选治疗肝纤维化的天然药物活性成分,为治疗慢性肝病开辟新视野。方法在GEO数据库中检索与肝纤维化相关的数据集,在FerrDb数据库收集与铁死亡相关靶点。将铁死亡与肝纤维化差异表达的交互靶点构建蛋白互作网络,并对关键靶点借助VarElect工具进行表型分析。通过WebGestalt数据库及omicshare平台对共同靶点进行富集分析。利用CTD定位药物小分子,并通过TCMSP找到天然药物小分子所来源的天然药物及其所对应靶点后进行分子对接分析。结果筛选到GSE171294数据集,差异分析后获取328个靶点,同时得到256个铁死亡靶点。进行交互处理后得到11个共同靶点,功能富集分析发现共同靶点与代谢过程、细胞增殖以及与谷氨酰胺代谢路径、mTOR信号通路等有关。CTD显示双酚A、槲皮素、白藜芦醇等15个天然活性成分与11个靶点具有对应关系,并且形成了较好的分子对接。结论通过生物大数据得到的来源于中药的15个天然活性成分具有调控铁死亡和肝纤维化的作用,本研究为肝纤维化药物的研发提供了思路,也为天然活性成分的研究提供科学参考。

关键词：肝纤维化铁死亡天然药物生物信息

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移动平均法在手足口病监测预警中的应用

医学动物防制 2024年第6期40卷 588-590,595页

作者：陶旭刘莹莹杨健郑立新董俊善史明坤秦皇岛市疾病预防控制中心河北秦皇岛066000 河北省疾病预防控制中心

目的探讨移动平均法在手足口病监测预警中的应用,为早期防控手足口病提供理论依据。方法利用Excel 2016软件对2015—2019年秦皇岛市手足口病报告发病数进行逐周统计,建立以周为时间序列的拟合方程。采用平均数、标准差等统计方法计算变... 详细信息

目的探讨移动平均法在手足口病监测预警中的应用,为早期防控手足口病提供理论依据。方法利用Excel 2016软件对2015—2019年秦皇岛市手足口病报告发病数进行逐周统计,建立以周为时间序列的拟合方程。采用平均数、标准差等统计方法计算变量值,并绘制秦皇岛市2020年手足口病预警控制图,对发病趋势进行预测预警。结果通过移动平均法制作预警控制图,得到基线、警戒线、行动线,并预测出2020年秦皇岛市手足口病高发时间在第23周至第37周,发病高峰在第29周。结论移动平均法可对传染病进行整体发病趋势预测预警,且操作简单,预测预警效果好,可以消除周期变动和随机波动的影响,是一种实用的传染病预测方法。疫情监测人员应在手足口病高发时段来临前做好健康宣教等工作,并根据每周手足口病病例的实际报告数,参考预警控制图及时做出做出相应的反应,减少主观判断。

关键词：手足口病移动平均法预测预警时间序列病例数

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基于食品用纸吸管新风险项目的分析研究

造纸科学与技术 2024年第1期43卷 56-60页

作者：张智力杨晓煜亓琛韩立鑫孙元浩徐珂梁金海许超山东省产品质量检验研究院山东省材料化学安全检测技术重点实验室国家包装产品质量检验检测中心(济南)山东济南250102

食品用纸吸管成为消费者关注的热点。重点分析了食品用纸吸管中氯丙醇、铝迁移量、多氯联苯、矿物油、邻苯二甲酸酯项目的检测情况和检出原因,提出了企业提高食品用纸吸管质量的措施,强调了生产中应重视并规范标签标识的使用,建议加强... 详细信息

食品用纸吸管成为消费者关注的热点。重点分析了食品用纸吸管中氯丙醇、铝迁移量、多氯联苯、矿物油、邻苯二甲酸酯项目的检测情况和检出原因,提出了企业提高食品用纸吸管质量的措施,强调了生产中应重视并规范标签标识的使用,建议加强对流通领域中纸吸管的监督抽查力度和风险监测的频次,探索实施“监督抽查+风险监测”的监管模式,尝试“标准内+标准外”项目的联合监管模式,同时建议加快纸制品的生产许可发证细则的修订进度,更好地规范食品包装用纸吸管产品的生产企业,最终保证产品质量。

关键词：食品用纸吸管风险项目

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地下空间盖挖逆作法施工技术及变形分析

施工技术（中英文） 2024年第1期53卷 39-45页

作者：朱雨轩魏德胜翟雷秦会来胡立新徐荣刘书蔚中国建筑第二工程局有限公司北京100160

以青岛地铁井冈山路站地下空间开发项目为背景,详细介绍了盖挖逆作法施工技术。为了系统地研究地下结构在施工过程中的变形规律,采用有限元软件对施工全过程进行精细化数值模拟研究,得到了不同施工阶段顶板沉降变形规律、施工对周边地... 详细信息

以青岛地铁井冈山路站地下空间开发项目为背景,详细介绍了盖挖逆作法施工技术。为了系统地研究地下结构在施工过程中的变形规律,采用有限元软件对施工全过程进行精细化数值模拟研究,得到了不同施工阶段顶板沉降变形规律、施工对周边地层变形的影响规律及不同开挖方式条件下竖向结构差异沉降规律。研究结果表明,采用对称开挖法时顶板产生的沉降最小为14.2mm,采用顺序开挖法次之,沉降值为15.2mm,而采用间隔开挖法产生的沉降最大为17.2mm,竖向结构的差异沉降满足规范要求,顶板不会出现开裂破坏。采用对称开挖法时竖向结构的最大沉降和最大差异沉降为3种开挖方式中最小,而采用间隔开挖法为最不利的开挖方式,其产生的最大沉降和差异沉降值为3种开挖方式中最大,故施工中应优先选择对称开挖法,避免选用间隔开挖法。

关键词：地铁车站地下空间盖挖逆作法对称开挖法差异沉降有限元分析

Investigation of longitudinal aerodynamic parameters identifcation method for fly-by-wire passenger airliners

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Chinese Journal of Aeronautics 2013年第5期26卷 1156-1163页

作者： Wu Zhao Wang lixin xu Zijian Tan Xiangsheng School of Aeronautic Science and Engineering Beihang University Flight Test Center Commercial Aircraft Corporation of China

The flight control system of a fly-by-wire （FBW） passenger airliner with a complex frame-work and high feedback gain augmentation would change the original characteristic of a loaded signal and suppress the excitation of an airplane＇s pertinent motion modes. Taking a research example of an FBW passenger airliner model with longitudinal relaxed-static-stability, a new method of signal type selection and signal parameter design is proposed, through analysis of signal energy distribution and plane body＇s frequency response. According to CCAR60--the Appraisal and Use Regulation of Flight Simulator Device, the simulation validation of the FBW passenger airliner＇s longitudinal aerodynamic parameters identification is put forward. The validation result indicates that the designed signal could excite the longitudinal motion mode of the FBW passenger airliner adequately and the multiparameter comparison in simulation meets the objective test request of CCAR60. Meanwhile, the relative errors of aerodynamic parameters are less than 10%.

关键词： CCAR60 Excitation signal design Fly-by-wire passenger air-liner High feedback gain augmentation Identification Longitudinal aerodynamic parameter Simulation validation

青少年自伤体验与需求质性研究的Meta整合

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循证护理 2024年第5期10卷 779-786页

作者：王国燕王艳娇唐莹徐永超赵明月吴丽欣昆明医科大学第一附属医院云南650032

目的:对青少年自伤体验的质性研究进行Meta整合,为制定青少年自伤预防方案干预策略提供参考。方法:系统检索PubMed、EMbase、Web of Science、the Cochrane Library、中国知网、万方数据库、维普数据库、中国生物医学文献服务系统中关... 详细信息

目的:对青少年自伤体验的质性研究进行Meta整合,为制定青少年自伤预防方案干预策略提供参考。方法:系统检索PubMed、EMbase、Web of Science、the Cochrane Library、中国知网、万方数据库、维普数据库、中国生物医学文献服务系统中关于青少年自伤体验的质性研究,检索时限为建库至2023年4月12日。采用澳大利亚Joanna Briggs Institute(JBI)循证卫生保健中心质性研究质量评价标准(2016)评价文献质量,采用汇集性Meta整合方法对结果进行整合。结果:共纳入14篇文献,提炼出48个主题,有1个研究结果与主题无关,最后纳入47个主题,形成11个新类别及4个整合结果(差异性的情绪反应形式,对自伤的认知与行为决策,身心双重不适,社交受限、渴望得到社会支持)。结论:青少年自伤发生率高,与多种因素有关,医护人员、家属应重视青少年身心健康,加强观察与评估,提供多方面支持,提升其自我情绪管理能力,有效预防自伤行为。

关键词：青少年自伤体验质性研究 Meta整合循证护理