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Robust sliding mode control with ESO for dual-control missile

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Journal of Systems Engineering and Electronics 2016年第5期27卷 1073-1082页

作者： wei shang shengjing tang jie guo yueyue ma yuhang yun School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China

This paper proposes a novel composite dual-control bycombing the integral sliding mode control （ISMC） method basedon the finite time convergence theory with extended state observer（ESO） for a tracking problem of a missile with tail fins and reactionjetcontrol system （RCS）. First, the ISMC method based on finitetime convergence is utilized to design the control law of tail fins andthe pulse control of RCS for the dual-control system, ensuring thesystem with rapid response and high accuracy of tracking. Then,ESO is employed for the estimation of aerodynamic disturbancesinfluenced by the airflow of thruster jets. With the characteristicof high accuracy estimation of ESO, the chattering free trackingperformance of the attack angle command and the robustnessof the control law are achieved. Meanwhile, the stability of thedual-control system is analyzed based on finite time convergencestability theorem and Lyapunov’s theorem. Finally, numerical simulationsdemonstrate the effectiveness of the proposed design.

关键词： reaction-jet control system (RCS) tail fins system,integral sliding mode control extended state observer (ESO).

Transient thermo-mechanical analysis for bimorph soft robot based on thermally responsive liquid crystal elastomers

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Applied Mathematics and Mechanics(English Edition) 2019年第7期40卷 943-952页

作者： yun CUI Yafei YIN Chengjun WANG K. SIM yuhang LI Cunjiang YU Jizhou SONG Institute of Solid Mechanics Beihang University Beijing 100191 China Department of Engineering Mechanics Soft Matter Research Center Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Zhejiang University Hangzhou 310027 China Materials Science and Engineering Program University of Houston Houston TX 77204 U. S.A. State Key Laboratory of Strength and Vibration of Mechanical Structures School of Aerospace Engineering Xi’an Jiaotong University Xi’an 710049 China Department of Mechanical Engineering University of Houston Houston TX 77204 U. S.A. Department of Electrical and Computer Engineering University of Houston Houston TX 77204 U. S.A. Department of Biomedical Engineering Texas Center for Superconductivity University of Houston Houston TX 77204 U. S.A.

Thermally responsive liquid crystal elastomers (LCEs) hold great promise in applications of soft robots and actuators because of the induced size and shape change with temperature. Experiments have successfully demonstrated that the LCE based bimorphs can be effective soft robots once integrated with soft sensors and thermal actuators. Here, we present an analytical transient thermo-mechanical model for a bimorph structure based soft robot, which consists of a strip of LCE and a thermal inert polymer actuated by an ultra-thin stretchable open-mesh shaped heater to mimic the unique locomotion behaviors of an inchworm. The coupled mechanical and thermal analysis based on the thermo-mechanical theory is carried out to underpin the transient bending behavior, and a systematic understanding is therefore achieved. The key analytical results reveal that the thickness and the modulus ratio of the LCE and the inert polymer layer dominate the transient bending deformation. The analytical results will not only render fundamental understanding of the actuation of bimorph structures, but also facilitate the rational design of soft robotics.

关键词： transient thermo-mechanical analysis soft robot thermal-responsive liq- uid crystal elastomer (LCE)

Effect of chiropractic manipulation on disrupted epithelium barrier and its mechanism of specialized pro-resolving mediators in a spleen-deficiency murine model

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Journal of Traditional Chinese Medicine 2019年第5期39卷 678-684页

作者： Xiong Ying Song Zhixiu Gu yun Qin yuhang Wei Jiangfei Lu Jinlu Zhu Y Teaching and Research Section of Tuina the Second Clinical Medical CollegeNanjing University of Chinese Medicine Nanjing 210023China Teaching and Research Section of Nutrition the Second Clinical Medical CollegeNanjing University of Chinese MedicineNanjing 210023China Laboratory of Acupuncture and Medicine Research of Ministry of Education the Second Clinical Medical CollegeNanjing University of Chinese MedicineNanjing 210023China

OBJECTIVE: To investigate the influence of spleen deficiency on the epithelial barrier of jejunum and lungs in a rat model of spleen-deficiency and the effect and potential specialized pro-resolving mediators (SPMs) mechanism of chiropractic manipulation. METHODS: Three-week-old male Sprague-Dawley rats were divided randomly into normal control group (n = 6), spleen-deficiency group (n = 5) and chiropractic group (n = 6). Spleen-deficiency model was induced in spleen-deficiency group and chiropractic group. Moreover, chiropractic manipulation was performed in chiropractic group. Four weeks later, systemic Th1/Th2 balance was evaluated by the ratio of plasma interferon (IFN)-γ/interleukin (IL)-4 levels by enzyme-linked immunosorbent assay (ELISA). Epithelial barrier integrity were assessed by the observation of morphological changes by hematoxylin-eosin staining and zonula occludens (ZO)-1 gene expressions by quantitative real time polymerase chain reaction in jejunum and lungs. Plasma resolvin D1 (RvD1) and lipoxin A4 (LXA4) levels were measures by ELISA for endogenous SPMs production. The levels of docosahexaenoic acid (DHA) and arachidonic acid (AA) in jejunum and lungs were also measured by HPLC-MS/ MS. RESULTS: Comparing with normal control group, spleen-deficiency group showed disrupted mucosa in jejunum, inflammatory condition in lungs, significantly decreased ratio of plasma IFN-γ/IL-4 levels and lower expressions of ZO-1 mRNA in both jejunum and lung tissues. Comparing with spleen-deficiency group, chiropractic group had less disrupted mucosa in jejunum and inflammatory condition in lungs, significantly increased systemic ratio of IFN-γ/IL-4 and expressions of ZO-1 mRNA in both jejunum and lung tissues. Chiropractic group had significantly enhanced plasma levels of RvD1 and LXA4, but had no significantly higher levels of DHA and AA in jejunum and lungs when comparing with spleen-deficiency group. CONCLUSION: Spleen deficiency caused systemic Th1/Th2 imbalanc

关键词： Manipulation, chiropractic Th1-Th2 balance Epithelial barrier Specialized pro-resolving mediators Spleen deficiency

Impacts of Integrated Multi-Trophic Aquaculture on Phytoplankton in Sanggou Bay

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Journal of Ocean University of China 2024年第3期23卷 835-843页

作者： HAN Jichang LIU Xing PAN Kehou LIU Jiaojiao SUN Yan JIN Guiyong LI yun LI yuhang College of Food Science and Engineering Ningbo UniversityNingbo 315832China Key Laboratory of Mariculture(Ocean University of China) Ministry of EducationQingdao 266003China Function Laboratory for Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and TechnologyQingdao 266100China Laboratory of Marine Organism Taxonomy and Phylogeny Institute of OceanologyChinese Academy of SciencesQingdao 266071China

Integrated multi-trophic aquaculture(IMTA)has been considered as an ecofriendly culture system providing a potential solution to environmental risks caused by intensive monoculture ***,the impact of IMTA on phytoplankton remains *** this study,the spatial and temporal variations of phytoplankton in Sanggou Bay were investigated seasonally based on 21 sampling sites covering three cultivation zones(bivalve zone,IMTA zone,and kelp zone)and one control zone(without aquatic cultivation).In total,128 phytoplankton species,with diatoms and dinoflagellates as the dominant groups,were obtained across the whole year,and the mean Shannon diversity index(H')and species richness(SR)were determined as 1.39 and 9.39,*** maximum chlorophyll a(Chl-a)(6.32μg L^(-1))and plankton diversity(H'of 1.97)occurred in summer and autumn,*** to other zones,the bivalve zone displayed significantly higher Chl-a and lower H'in majority of *** PERMANOVA analysis indicated that the phytoplankton assemblage in the bivalve zone was significantly different with the control and kelp zones,while the IMTA zone maintained close to other three *** on generalized additive models,temperature,NO_(2)^(-)-N,N/P ratio,SiO_(3)^(2-)-Si,and salinity were determined as the key factors underlying Chl-a and phytoplankton ***-tionally,the results of redundancy analysis further indicated that the phytoplankton assemblage in the bivalve zone is positively re-lated with nutrients such as NO_(3)^(-)-N and NH_(4)^(+)-N as well as water depth,while the phytoplankton assemblages in the kelp,control,and IMTA zones are associated with NO_(2)^(-)-N,SiO_(3)^(2-)-Si,and *** all observations into consideration together,it can be inferred that IMTA can effectively reduce Chl-a level compared to bivalve monoculture by reducing the ***,the SR,H’,and species composition of phytoplankton are primarily determined by local environment fa

关键词： phytoplankton diversity Sanggou Bay integrated multi-trophic aquaculture

Revealing the spacing effect of neighboring side-chains in modulating molecular aggregation and orientation of M-series acceptors

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Aggregate

Aggregate 2023年第4期4卷 166-176页

作者： yunlong Ma Shaoxin Luan Dongdong Cai Shu-Quan Zhang Jin-yun Wang Qisheng Tu yuhang Zhu Qingdong Zheng State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouChina College of Chemistry and Materials Science Fujian Normal UniversityFuzhouChina College of Zhicheng Fuzhou UniversityFuzhouChina State Key Laboratory of Coordination Chemistry College of Engineering and Applied SciencesNanjing UniversityNanjingChina

Controlling the aggregation of small-molecule acceptors(SMAs)is essential to obtain an optimal morphology and to improve the photovoltaic performance of polymer solar cells(PSCs).However,reducing intermolecular aggregation of SMAs is usually accompanied by the disruption of compact molecular packing thereby leading to their decreased electron ***,two novel M-series SMAs(MD1T and MD2T)based on ladder-type heterononacenes with neighboring side-chains separated by one or two thiophene rings are designed and *** is found that shortening the spacing of the neighboring side-chains of the SMAs can greatly alleviate the intermolecular aggregation and alter the molecular orientation from bimodal edge-on/face-on to predominant face-on while maintaining the compact molecular *** a result,a more favorable morphology with smaller domain sizes is formed for the MD1T-based blend films,which greatly improves the charge generation and charge transport for the corresponding *** best-performing MD1T-based device affords an efficiency of 12.43%,over seven times higher than that of the MD2T-based *** work reveals the importance of the spacing between the neighboring side-chains in modulating the molecular aggregation and active layer morphology,and the obtained structure-performance relationships shall provide important guidance for designing highly efficient SMAs.

关键词： aggregation molecular orientation neighboring side-chains polymer solar cells small-molecule acceptors

基于HRRP时频特征和多尺度非对称卷积神经网络的目标识别算法

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西北工业大学学报 2023年第3期41卷 537-545页

作者：云涛潘泉郝宇航徐蓉西北工业大学自动化学院陕西西安710129 中国人民解放军63768部队陕西西安710600 信息融合技术教育部重点实验室陕西西安710114

针对空间目标识别中特征提取难、准确率低等问题,提出了一种基于雷达高分辨率距离像(high range resolution profile,HRRP)时频特征和多尺度非对称卷积神经网络的目标识别算法。采用离差标准化、多特显点绝对对齐消除目标的强度敏感性... 详细信息

针对空间目标识别中特征提取难、准确率低等问题,提出了一种基于雷达高分辨率距离像(high range resolution profile,HRRP)时频特征和多尺度非对称卷积神经网络的目标识别算法。采用离差标准化、多特显点绝对对齐消除目标的强度敏感性和平移敏感性,利用雷达多普勒测速数据消除目标高速运动对HRRP产生的展宽、畸变、波峰分裂等影响。对HRRP进行时频分析,提取其时频特征。通过不同尺度的非对称卷积,实现时频特征不同精细程度和不同方向的特征提取。实测数据处理结果表明,文中方法目标识别准确率高,而且在同平台目标识别、抗姿态敏感性等方面具有很好的效果。

关键词：雷达目标识别逆合成孔径雷达高分辨率距离像卷积神经网络

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人口老龄化背景下的村庄失活与乡村振兴挑战

中国农业大学学报（社会科学版） 2023年第2期40卷 55-69页

作者：孔铭吕宇航赵云中国农业大学人文与发展学院

将村庄视作一个具有生命力的整体,拥有“活力”意味着村庄拥有生机和内生动力,“失活”即村庄失去活力的过程及由此产生的状态。本文基于5省10村的调研发现,当前一部分村庄正呈现出活力不足或“失活”样态,由人口结构转变所带来的乡村... 详细信息

将村庄视作一个具有生命力的整体,拥有“活力”意味着村庄拥有生机和内生动力,“失活”即村庄失去活力的过程及由此产生的状态。本文基于5省10村的调研发现,当前一部分村庄正呈现出活力不足或“失活”样态,由人口结构转变所带来的乡村社会整体性变迁已成为乡村振兴战略推进过程中必须面对的现实问题。随着人口老龄化程度不断加深,村庄“失活”将使全方位的农业农村现代化面临多重挑战。研究认为,应基于村庄失活的多重表征,把握老龄化村庄所拥有的发展基础和发展愿景,以及老年群体所面临的生产生活难题,由此探索适应性的乡村振兴路径。

关键词：活力失活人口老龄化乡村振兴

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基于网络资源流量的链路预测方法

计算机工程 2022年第9期48卷 78-88页

作者：刘宇航尹小庆林云重庆大学机械与运载工程学院重庆400044 重庆大学管理科学与房地产学院重庆400044

在复杂网络中,现有基于结构相似性的链路预测方法较少考虑全局和局部拓扑信息之间平衡性、准确度和复杂度之间平衡性以及网络资源动态流动的问题。将网络资源流量作为相似性判断依据,提出一种准局部链路预测方法。根据网络中节点重要性... 详细信息

在复杂网络中,现有基于结构相似性的链路预测方法较少考虑全局和局部拓扑信息之间平衡性、准确度和复杂度之间平衡性以及网络资源动态流动的问题。将网络资源流量作为相似性判断依据,提出一种准局部链路预测方法。根据网络中节点重要性的不同来为它们分配对应的资源,以保证资源分配的合理性。针对网络资源提出一种动态流动机制,将节点对双向流动的资源之和作为相似程度的量化指标。引入节点对之间中间路径节点的概念,分析中间路径节点在资源流动过程中的稀释作用。在此基础上,计算初始资源量和稀释作用量从而得到网络资源流量方法的性能评估指标值。在Jazz、NS等11个真实世界的网络中进行实验,对比该方法与CN、Salton等常见基准方法在准确度和鲁棒性方面的性能表现,结果表明,所提方法能够充分利用准局部信息,既能考虑资源流动性又能解决平衡性问题,可有效提高链路预测性能。

关键词：复杂网络链路预测资源流动双向流量准局部路径

Grey hematite photoanodes decrease the onset potential in photoelectrochemical water oxidation

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Science Bulletin 2021年第10期66卷 1013-1021,M0004页

作者： Peng-Fei Liu Chongwu Wang yun Wang yuhang Li Bo Zhang Li-Rong Zheng Zheng Jiang Huijun Zhao Hua-Gui Yang Key Laboratory for Ultrafine Materials of Ministry of Education Shanghai Engineering Research Center of Hierarchical NanomaterialsSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Centre for Clean Environment and Energy Griffith UniversityGold Coast CampusQLD 4222Australia State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science and Laboratory of Advanced MaterialsFudan UniversityShanghai 200438China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201204China

Photoelectrochemical(PEC)water splitting for solar energy conversion into chemical fuels has attracted intense research *** semiconductor hematite(α-Fe_(2)O_(3)),with its earth abundance,chemical stability,and efficient light harvesting,stands out as a promising photoanode ***,its electron affinity is too deep for overall water splitting,requiring additional *** engineering has been used to reduce the onset potential of hematite *** we focus instead on energy band engineering hematite by shrinking the crystal lattice,and the water-splitting onset potential can be decreased from 1.14 to 0.61 V *** reversible hydrogen *** is the lowest record reported for a pristine hematite photoanode without surface modification.X-ray absorption spectroscopy and magnetic properties suggest the redistribution of 3d electrons in the as-synthesized grey hematite *** function theory studies herein show that the smaller-lattice-constant hematite benefits from raised energy bands,which accounts for the reduced onset potential.

关键词： Hematite Photoelectrochemical water oxidation Onset potential Spin states Energy band