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基于粒子群算法的火炮伺服系统摩擦参数辨识

清华大学学报（自然科学版） 2007年第z2期47卷 1717-1720页

作者：张文静赵先章台宪青中国科学院自动化研究所综合信息系统研究中心北京100080

针对火炮交流伺服系统中存在的非线性动态摩擦,为了提高火炮伺服系统的跟踪精度,提出了一种基于粒子群的LuGre摩擦参数两步辨识方法。利用Stribeck曲线辨识了4个静态参数,利用滞滑极限辨识了2个动态参数,完成了摩擦力矩的动态补偿。实... 详细信息

针对火炮交流伺服系统中存在的非线性动态摩擦,为了提高火炮伺服系统的跟踪精度,提出了一种基于粒子群的LuGre摩擦参数两步辨识方法。利用Stribeck曲线辨识了4个静态参数,利用滞滑极限辨识了2个动态参数,完成了摩擦力矩的动态补偿。实验结果表明了该算法的合理性,火炮伺服系统的正弦跟踪最大误差为1.25 mrad,精度完全达到了军标要求。

关键词：火炮交流伺服 LuGre摩擦模型粒子群

Recognition of amphetamine/ibuprofen enantiomers by heterocyclic decapeptides

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Recognition of amphetamine/ibuprofen enantiomers by heterocy...

中国化学会第30届学术年会-第十八分会：电子结构理论方法的发展与应用

作者： Xue Li Yanyan Zhu wenjing zhang Donghui Wei Mingsheng Tang College of Chemistry and Molecular Engineering Zhengzhou University

Molecule recognition of chiral organic molecules by a host has become a topic of strong interest over the past decades in biomimetic organic chemistry, supramolecular chemistry, biology, and pharmacy [1,2]. Various types of hosts, such as cyclodextrins, cucurbituril, cationic pillar[n]arenes, crown ethers and calixarenes, all with the high symmetry and rigidity, present potentials of chiral recognition on organic enantiomer. However, the deficiency of conformational flexibility is a limitation regarding efficiency of inclusion complex. Recently, cyclopeptide derivatives [3,4] have attracted much attention owning to their high conformational flexibilities. In this work, the conformational and structural features of sixteen inclusion complexes of four cyclopeptides including one cyclic decapeptide(CDP) and three heterocyclic CDPs(named as I-CDP, E-CDP and H-CDP) with two enantiomers(amphetamine and ibuprofen are respectively named as AP and IP) were investigated using three density functional theories of B3LYP, CAM-B3LYP and M06-2X. The large binding energies(BE) of the five inclusion complexes, that is, the two of H-CDP/AP and H-CDP/IP by B3LYP calculation, the two of I-CDP/IP and H-CDP/IP by CAM-B3LYP, and the other one of I-CDP/IP via M06-2X method, are mainly determined by their corresponding stable geometries, electronic properties, and molecular orbitals. The existing hydrogen bonds with E(2) values and NBO analyses of the inclusion complexes further identify the relatively larger BE and △△E values. The EPS potentials and non-bonded weak interactions for the studied systems elaborated the reasons why the AP and IP enantiomers are recognized by the heterocyclic CDPs at such conformations. Possible mutants of cyclopeptides may greatly improve the corresponding molecular recognition ability on the certain enantiomers.

关键词： recognition cyclopeptide inclusion complexes enantiomers

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一种高效率圆极化背腔天线阵的设计

电波科学学报 2014年第1期29卷 129-134页

作者：宋长宏吴群张文静路志勇哈尔滨工业大学电子信息工程学院黑龙江哈尔滨150001 中国电子科技集团公司第五十四研究所河北石家庄050081

设计了一种新型单臂螺旋边馈阶梯喇叭圆极化背腔天线,天线单元由阶梯喇叭、单臂螺旋及圆形背腔组成.单臂螺旋采用准空气同轴线激励,给出了天线单元的轴比、驻波、方向图宽频带特性.提出单元旋转反相馈电方法改善了天线子阵轴比和极化隔... 详细信息

设计了一种新型单臂螺旋边馈阶梯喇叭圆极化背腔天线,天线单元由阶梯喇叭、单臂螺旋及圆形背腔组成.单臂螺旋采用准空气同轴线激励,给出了天线单元的轴比、驻波、方向图宽频带特性.提出单元旋转反相馈电方法改善了天线子阵轴比和极化隔离,同时解决了馈电空间狭小的难题.对阵列进行了加工测试,测试与仿真结果吻合.结果显示,天线增益、驻波带宽、轴比带宽和方向图性能优良,此种天线具有很好的工程应用前景.

关键词：单臂螺旋阶梯喇叭圆极化高效率

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基于通道注意力机制的行人重识别方法

北京航空航天大学学报 2022年第5期48卷 881-889页

作者：孙义博张文靖王蓉李冲张琪中国人民公安大学信息网络安全学院北京100038

针对行人特征表达不充分的问题,提出了一种基于通道注意力机制的行人重识别方法。将通道注意力机制SE模块嵌入到骨干网络ResNet50中,对关键特征信息进行加权强化;采用动态激活函数,根据输入特征动态调整ReLU的参数,增强网络模型的非线... 详细信息

针对行人特征表达不充分的问题,提出了一种基于通道注意力机制的行人重识别方法。将通道注意力机制SE模块嵌入到骨干网络ResNet50中,对关键特征信息进行加权强化;采用动态激活函数,根据输入特征动态调整ReLU的参数,增强网络模型的非线性表达能力;将梯度中心化算法引入Adam优化器,提升网络模型的训练速度和泛化能力。在Market1501、DukeMTMC-ReID和CUHK03主流数据集上对改进后的模型进行测试评价,Rank-1分别提升2.17%、2.38%和3.50%,mAP分别提升3.07%、3.39%和4.14%。结果表明:改进后的模型能够提取更强鲁棒性的行人表达特征,达到更高的识别精度。

关键词：通道注意力机制动态激活函数梯度中心化特征提取行人重识别

An Operation Control Strategy for Medium-speed Maglev Train in Station Based on On-board Battery Condition Monitoring

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An Operation Control Strategy for Medium-speed Maglev Train ...

第30届中国控制与决策会议

作者： Wenjun Wei wenjing zhang Nan Nan Yifan Yang Yuefeng Liu School of Electronic and Information Engineering Beijing Jiaotong University R&D Center CRRC Tangshan Co. Ltd.

To meet the requirements of the rapidly developing magnetic levitation transport system for the safe operation of medium-speed maglev trains with a maximum speed of 200 km/h. A method of monitoring on-board battery condition based on Internet of Things（IoT） is proposed and a station operation control strategy is given. This method analyzes the effect of on-board battery on the minimum operation speed curve and combines the technical characteristics of IoT with the required parameters for maglev train operation control. A sensor network with IoT architecture is designed to monitor battery condition. The strategy aiming at controlling maglev train to power rail（PR） district ensures the safety and efficiency of its pull-in and departure process. The simulation verifies the proposed monitoring approach and the station operation control strategy can guarantee safety of train operation.

关键词： Medium-speed maglev train On-board battery Internet of Things Operation control strategy

A Section Decentralization Operation Strategy For Medium-Speed Maglev Train Based On Battery States

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A Section Decentralization Operation Strategy For Medium-Spe...

第37届中国控制会议

作者： Yifan Yang Nan Nan Wenjun Wei wenjing zhang Yuefeng Liu School of Electronic and Information Engineering Beijing Jiaotong University CRRC Tangshan Co. Ltd.

Due to the uniqueness of power supply mode for the medium-speed maglev train, the vehicle-borne battery has a straight impact on the train operation safety and its states have to be considered during the operation strategy making. In this paper, taking temperature and remaining capacity of the battery into consideration, a section decentralization operation strategy is proposed to guarantee the maglev train stop in the designated Auxiliary Stopping Area with Power Rail in case of ***, the battery states are monitored by sensor network and sent to Vehicle Safety Computer. Then, combining the current train state, the operation strategy is adjusted by Vehicle Safety Computer. The simulation verifies the effectiveness of the proposed strategy.

关键词： Medium-Speed Maglev System Operation Control Vehicle-borne Battery Control Strategy Section Decentralization

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系统参数对浮环轴承转速比的动态影响

四川大学学报（工程科学版） 2015年第3期47卷 160-166页

作者：张文静陈渭李培门日秀西安交通大学现代设计及转子轴承系统教育部重点实验室陕西西安710049 中国北方发动机研究所柴油机高增压技术国家级重点实验室天津300400

转速比即环速比和轴颈涡动比是涡轮增压器浮环轴承系统的功耗和稳定性研究的重要指标。基于经典短轴承理论,考虑浮环和轴颈的回转变位角速度,推导出内外层非线性动载油膜力的解析模型。考虑轴系的偏心质量引起的离心力,建立了涡轮增压... 详细信息

转速比即环速比和轴颈涡动比是涡轮增压器浮环轴承系统的功耗和稳定性研究的重要指标。基于经典短轴承理论,考虑浮环和轴颈的回转变位角速度,推导出内外层非线性动载油膜力的解析模型。考虑轴系的偏心质量引起的离心力,建立了涡轮增压器浮环轴承系统非线性动力学模型。仿真得到环速比和轴颈涡动比随转速的变化曲线,并分析研究了不同转速下偏心质量、润滑油粘度、浮环结构参数等对环速比和涡动比的动态影响机制,及转速比对系统参数敏感程度的变化规律。为浮环轴承的设计研发和涡轮增压器浮环轴承系统的性能评价提供了重要参考。

关键词：浮环轴承环速比涡动比系统参数动载涡轮增压器

物流业集聚对城市群经济韧性的影响机制——基于人力资本的调节作用

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商业经济研究 2024年第23期 89-92页

作者：张文静晋中信息学院经济与管理学院山西晋中030800

物流业集聚通过降低物流成本、加强产业链与供应链的连接与协同、促进创新与技术升级以及扩大市场辐射范围等提高城市群经济适应能力和应对风险能力,进而提升城市群经济韧性。基于此,本文选取2013-2022年相关面板数据,对我国7大城市群... 详细信息

物流业集聚通过降低物流成本、加强产业链与供应链的连接与协同、促进创新与技术升级以及扩大市场辐射范围等提高城市群经济适应能力和应对风险能力,进而提升城市群经济韧性。基于此,本文选取2013-2022年相关面板数据,对我国7大城市群物流业集聚与经济韧性之间的关系进行研究。结果发现,物流业集聚可以有效促进城市群经济韧性水平提升,人力资本在其中发挥调节作用与门槛效应。基于以上结论,本文从物流业集聚、城市群经济韧性以及人力资本三大方面提出优化策略。

关键词：物流业集聚城市群经济韧性人力资本

An Operation Control Strategy of Pull-In and Departure Station for Medium-Speed Maglev Train with Battery Constraints

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An Operation Control Strategy of Pull-In and Departure Stati...

第37届中国控制会议

作者： Nan Nan Yifan Yang Wenjun Wei wenjing zhang Yuefeng Liu School of Electronics and Information Engineering Beijing Jiaotong University R&D Center CRRC Tangshan Co. Ltd.

To guarantee the operation safety of medium-speed maglev train in case of emergency, considering the remaining capacity of vehicle-borne batteries, a strategy of pull-in and departure station is proposed to minimize the energy consumption for levitation and braking. In pull-in process, the train runs for a specific distance at an optimal speed obtained according to minimum energy consumption and then an braking is taken to stop train at the designated point. In departure station process,minimum remaining capacity of the battery is calculated to guarantee the train runs to next nearest Auxiliary Stoping Area（ASA）.The simulation results show the effectiveness of the proposed operation strategy.

关键词： Medium-speed Maglev Train Operation Control Strategy Vehicle-borne Battery Remaining Capacity