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Decentralized Event-Triggered Output Consensus for Heterogeneous Multi-Agent Systems with General Linear Dynamics 36

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Decentralized Event-Triggered Output Consensus for Heterogen...

第36届中国控制会议

作者： xiangdong liu Changkun Du Haikuo liu Pingli Lu School of Automation Beijing Institute of Technology

ISBN: (纸本)9781538629185

In this paper,we study the event-triggered consensus problem for heterogeneous multi-agent systems with general linear dynamics under a general directed *** the states of each agent are unavailable,we propose a decentralized eventtriggered consensus control strategy based on observer and internal model principle such that the outputs of all agents achieve consensus,without requiring continuous communication among the *** feasibility of the event-triggered strategy is further verified by the exclusion of Zeno behavior,that is,the event would not be triggered ***,simulation is given to illustrate the theoretical analysis.

关键词： Event-triggered consensus control heterogeneous multi-agent systems general linear dynamics

Chaotic Particle Swarm Optimization Algorithm Parametric Identification of Bouc-Wen hysteresis Model for Piezoelectric Ceramic Actuator

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Chaotic Particle Swarm Optimization Algorithm Parametric Ide...

第25届中国控制与决策会议

作者： Ning Dong Hongjuan Li xiangdong liu Key Laboratory for Intelligent Control & Decision of Complex Systems Beijing Institute of Technology School of Automation Beijing Institute of Technology

ISBN: (纸本)9781467355339

A chaotic particle swarm optimization (CPSO) algorithm is proposed by introducing chaos state into the original Particle Swarm Optimization (PSO) which aims to solving the flaws of easy plunging into local optimum and losing search ability in the last period for the fast particle velocity decrease. CPSO algorithm takes advantage of the ergodicity, randomicity, and regularity of chaos to make chaotic searching for the global extremun at the same time with the particle swarm optimization. This algorithm synthesizes the high efficiency of global optimization of PSO algorithm and the ergodicity and randomicity of local search of chaotic algorithm. This paper utilizes aforementioned algorithm to identify the Bouc-Wen hysteresis model for piezoelectric ceramic actuators (PCA). The experimental results show that the model identified by CPSO algorithm has better performance than that by PSO algorithm.

关键词： Chaotic Particle Swarm Optimization Bouc-Wen Identification Piezoelectric Ceramic Actuator

PMCMC for Term Structure of Interest Rates under Markov Regime Switching and Jumps

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Journal of Systems Science and Information 2020年第2期11卷 159-169页

作者： xiangdong liu Xianglong LI Shaozhi ZHENG Hangyong QIAN Department of Statistics Jinan UniversityGuangzhou 510632China

A parameter estimation method,called PMCMC in this paper,is proposed to estimate a continuous-time model of the term structure of interests under Markov regime switching and *** is a closed form solution to term structure of interest rates under Markov ***,the model is extended to be a CKLS model with non-closed form solutions which is a typical nonlinear and non-Gaussian state-space model(SSM)in the case of adding *** the difficulty of parameter estimation greatly prevents from researching models,we prove that the nonlinear and non-Gaussian state-space model has better performances in studying *** method proposed in this paper will be implemented in simulation and empirical study for *** results illustrate that the PMCMC algorithm has powerful advantages in tackling the models.

关键词： PMCMC term structure of interest rates state-space models regime switching jump-diffusion

Second-Order Time-Varying Sliding Mode Control for Uncertain Systems

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Second-Order Time-Varying Sliding Mode Control for Uncertain...

第25届中国控制与决策会议

作者： Jie Geng Yongzhi Sheng xiangdong liu Bing liu School of Automation Beijing Institute of Technology Key Laboratory of Complex System Intelligent Control and Decision Ministry of Education

ISBN: (纸本)9781467355339

A novel second-order time-varying sliding mode control（SOTVSMC） law is proposed for the robust tracking control problem of nonlinear smooth single-input single-output（SISO） system with disturbance. The advantages of the proposed SOTVSMC are twofold. The global second order sliding mode is established, which implies that the closed-loop system is global robust against matched parameter uncertainties and disturbances. Meanwhile, the chattering problem is significantly alleviated. Then the parameter of the sliding mode is obtained by solving an optimal problem. Finally, the effectiveness and robustness of the control strategy is demonstrated by simulation results.

关键词： Sliding Mode Control Nonlinear Systems Global Second Order Sliding Phase Chattering Alleviation

Cytological mechanisms of interspecific incrossability and hybrid sterility between Oryza sativa L. and O. alta Swallen

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Chinese Science Bulletin 2007年第6期52卷 755-765页

作者： FU XueLin LU YongGen liu xiangdong Li JinQuan Feng JiuHuan Guangdong Provincial Key Laboratory of Plant Molecular Breeding South China Agriculture University Guangzhou 510642 China

Oryza sativa and O. alta belong to AA and CCDD genomes in Oryza, respectively. Interspecific repro-ductive isolation limits the transfer of favorable genes from O. alta into O. sativa. The cytological mechanisms of interspecific incrossability and hybrid sterility between O. sativa and O. alta were studied systematically in this paper. We indentified two cytological causes of interspecific incrossabil-ity. First, we observed embryo sac incompatibility that caused fertilization barriers of variable severity such as non-fertilization, fertilization stagnation and egg cell single-fertilization. Second, we observed hybrid inviability, the major cause for incrossability, apparent from hybrid embryo developmental stagnation and embryo abortion. Hybrid sterility included both embryo sac sterility and pollen sterility. The hybrid embryo sac was completely sterile and exhibited mainly embryo sac degeneration. Hybrid pollen was also sterile and mainly typical abortive. Hybrid sterility was mainly caused by severely ab-normal meioses of megasporocytes and pollen mother cells; it is the most important abnormality, being chromosome sterility. Several methods are suggested to overcome the interspecific reproductive iso-lation between O. sativa and O. alta.

关键词：栽培稻高秆野生稻种间不可杂交性杂种不育细胞机制种间不可交配性

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玉米秸秆压缩特性试验研究

农机化研究 2025年第2期47卷 153-158页

作者：郭思佳刘新柱刘春山刘向东邢蕾栾积毅韩平王海祥李剑英佳木斯大学机械工程学院黑龙江佳木斯154007

为了更好地利用玉米秸秆这种生物质材料,同时为设计和优化秸秆收获、打捆、切割等装置结构提供一定的技术参数,对寒地玉米秸秆进行了压缩试验。设计了三因素三水平的正交试验,并结合自制试验装置,利用万能试验机、数显鼓风干燥箱等设备... 详细信息

为了更好地利用玉米秸秆这种生物质材料,同时为设计和优化秸秆收获、打捆、切割等装置结构提供一定的技术参数,对寒地玉米秸秆进行了压缩试验。设计了三因素三水平的正交试验,并结合自制试验装置,利用万能试验机、数显鼓风干燥箱等设备对玉米秸秆进行了有节段的径向和轴向压缩试验,测得了基于不同部位、不同速度、不同含水率三因素在不同水平组合下的破坏力的大小,获得因素的显著性影响程度及最优水平组合。试验结果表明:玉米秸秆轴向压缩破坏力为0.726~3.271 kN,R值为0.586~1.527,F值为7.093~38.742;玉米秸秆径向压缩破坏力为0.370~2.297 kN,R值为0.382~0.921,F值为9.096~22.183。分析得出:各因素对试验指标影响极显著的是秸秆部位,加载速度和含水率次之;最优水平组合为秸秆部位为上、加载速度为10 mm/min、含水率为最低,且径向压缩所需破坏力小于轴向压缩所需破坏力。

关键词：玉米秸秆压缩含水率

Nanocrystalline La2Mo2O9 and Its Characterization

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Journal of Rare Earths 2004年第Z2期22卷 102-106页

作者： Li Qin Xia Tian Li Jiayan liu xiangdong Ma Xianfeng Meng Jian Cao Xueqiang Key Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied ChemistryChinese Academy of Sciences.Changchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of Sciences.Changchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of Sciences.Changchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of Sciences.Changchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of Sciences.Changchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of Sciences.Changchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of Sciences.Changchun 130022China

In this work, both the thermal expansion and electrical conductivity of nanocrystalline La2Mo2O9 were *** nanocrystalline powder of La2Mo2O9 was obtained by sol-gel method, and with the help of SHP (superhigh pressure)up to 4.5 × 104 atm at 700 ℃ for a short time, and the nanocrystalline powder was densified without obvious particle size growth. The electrical conductivity of nanocrystalline La2Mo2O9 was one orderof magnitude lower than that of the microcrystalline sample at the same temperature. Owing to the phase transition, the microcrystalline La2Mo2O9 has an abrupt increase of thermal expansion with a peak value of 48 × 10-6 K-1 at 556 ℃. For the nanocrystalline material, the peak value increases to 112 × 10-6 K-1 at 520 ℃. On the other hand, above 600 ℃ the significant growth of particle size of the nanocrystalline La2Mo2O9 was observed, accompanying by a tremendous increase of thermal expansion with a peak value of third higher than that of La2Mo2O9.

关键词： nanocrystalline electrical conductivity lanthanum molybdate superhigh pressure rare earths

Integrated guidance and control based on high-order sliding mode method 36

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Integrated guidance and control based on high-order sliding ...

第36届中国控制会议

作者： Ran Huo xiangdong liu Xiangyuan Zeng Zhirong Lei School of Automation Beijing Institute of Technology School of Automation Northwestern Polytechnical University

ISBN: (纸本)9781538629185

Under the coupling effect between guidance system and control system,the performance of traditional guidance and control method is ***,integrated guidance and control(IGC) method is proposed to solve the *** method is characterized by the guidance loop and control loop which are considered as a whole part in accordance with the information of the relative motion between the aircraft and the target or trajectory,directly generating a command of actuator angle *** this paper,simplifying kinematics and dynamics equations of the aircraft are primarily based on ***,sliding mode controller is designed to make the whole system asymptotically *** designing the system controller,it uses a high-order sliding mode controller instead of the commonly backstepping design *** advantages of IGC over ordinary method is that it not only simplifies the design process and shortens the time cost,but also increases the potential and reduces the manufacturing cost of the *** the basis of the experimental results,the high-order sliding mode controller can guarantee the stability of the aircraft system,which also has fast responding time and can intercept the target accurately.

关键词： integrated guidance and control high order sliding mode controller

Stand biomass of Pinus sylvestris var. mongolica plantations benefits from high density monocultures in the boreal zone

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Forest Ecosystems 2024年第5期11卷 650-658页

作者： Bingming Chen Shensi liu Jinghua Yu Yanqing Huang Shuai Yu Huanchu liu Tianyu Zhang xiangdong liu Guangze Jin Wei Chen Xingyuan He CAS Key Laboratory of Forest Ecology and Silviculture Institute of Applied EcologyChinese Academy of SciencesShenyang110016China University of Chinese Academy of Sciences Beijing100049China Shenyang Arboretum Chinese Academy of SciencesShenyang110016China Liaoning Shenyang Urban Ecosystem National Observation and Research Station Shenyang 110164China College of Forestry Shenyang Agricultural UniversityShenyang110866China Center for Ecological Research Northeast Forestry UniversityHarbin150040China Key Laboratory of Sustainable Forest Ecosystem Management Ministry of EducationNortheast Forestry UniversityHarbin150040China Northeast Asia Biodiversity Research Center Northeast Forestry UniversityHarbin150040China

Pinus sylvestris ***(***)plantations are extensively established in the boreal *** stand biomass of these plantations can effectively enhance carbon stock,which is crucial for mitigating climate ***,the current understanding of optimizing plantation strategies to maximize stand biomass is primarily derived from experiments in tropical and subtropical zones,which is difficult to extend to the boreal due to substantial climatic *** on a comprehensive dataset from 1,076 sample plots of *** plantations in the boreal zone of China,we evaluated the effects of tree species richness and stand density on tree height,diameter at breast height(DBH),and stand biomass to investigate the optimal plantation ***,we examined how these effects changed with stand age and investigated their relative *** found that monocultures at a high stand density of 2,000–2,500ha^(−1) were the optimal plantation strategy to maximize stand biomass(107.5Mg·ha^(−1)),and this held true at almost all stand ***,this strategy resulted in low species richness and small individual trees(10.6m height and 9.8cm DBH),thus presenting a *** addition,as stand age increased,the effect of tree species richness on stand biomass shifted from positive to negative,but the effect of stand density was always ***,stand age had the greatest effect on stand biomass,followed by stand density and then tree species *** findings reveal a distinct plantation strategy for optimizing stand biomass of *** plantations in the boreal *** importantly,this study highlights that(1)maximizing stand biomass in the boreal zone may compromise tree species richness;(2)net effects of tree species richness on stand biomass are not always positive,as negative selection effects offset positive complementary effects.

关键词： Boreal forests Cold region Forestry application Mongolian Scots pine Planting strategy Tree diversity