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基于LMI的具有输入时滞不确定系统鲁棒控制器的设计

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吉林大学学报（工学版） 2006年第6期36卷 924-928页

作者：张涛李元春吉林大学通信工程学院长春130022

研究了具有固定输入时滞不确定系统的鲁棒镇定问题,并针对现有的还原算法设计出来的鲁棒控制器复杂且难实现的缺点,给出了一种改进的还原方法,得到了一个通过求解线性矩阵不等式(LM I)来获得鲁棒稳定化控制器的设计方法,设计出的控制器... 详细信息

研究了具有固定输入时滞不确定系统的鲁棒镇定问题,并针对现有的还原算法设计出来的鲁棒控制器复杂且难实现的缺点,给出了一种改进的还原方法,得到了一个通过求解线性矩阵不等式(LM I)来获得鲁棒稳定化控制器的设计方法,设计出的控制器计算简单且易实现。数值算例及仿真结果表明了算法的有效性和优越性。

关键词：自动控制技术输入时滞还原方法鲁棒控制器不确定系统

政府卫生支出对区域经济的空间溢出效应研究——基于山东省17市的空间面板模型

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华东经济管理 2019年第3期33卷 19-24页

作者：陶春海王玉晓江西财经大学统计学院江西南昌330013

文章基于空间统计学的研究视角,运用全域和局部空间Moran’s I指数散点图考察了山东省2006-2016年政府卫生支出与各地区GDP的空间相关性和空间集聚现象,并通过构建空间杜宾模型进一步分析了山东省政府卫生支出对经济增长的影响。结果显... 详细信息

文章基于空间统计学的研究视角,运用全域和局部空间Moran’s I指数散点图考察了山东省2006-2016年政府卫生支出与各地区GDP的空间相关性和空间集聚现象,并通过构建空间杜宾模型进一步分析了山东省政府卫生支出对经济增长的影响。结果显示:山东省政府卫生支出空间相关性出现先减弱后增强的现象,政府卫生支出与经济增长的空间分布表现出明显的非均质性;人均政府卫生支出对区域经济增长存在显著正向溢出效应,且直接效应与间接效应系数相近,政府医疗支出对经济增长表现出较强的空间溢出;就业率对经济增长表现出较强的影响效应,其每提高一个百分点,给本地区和其他地区分别带来232 821.7元和194 567.5元的经济收益,而万人床位数和万人医疗卫生人员因其配置严重不均衡导致对经济增长表现出负向影响。基于此,文章给出了相应建议。

关键词：医疗卫生支出空间溢出效应经济增长空间杜宾模型空间面板

Swallowtail model for predicting the global bifurcation behavior of CO oxidation reactions

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Science China Chemistry 2011年第7期54卷 1072-1077页

作者： CUI tao TANG ShunLin ZHANG Lei YU DaRen School of Energy Science and Engineering Harbin Institute of Technology Harbin 150001 China Pharmaceutical College Heilongjiang University of Chinese Medicine Institution Harbin 150040 China

Catalytic CO oxidation on platinum group metals exhibits nonlinear phenomena such as hysteresis and *** of the nonlinear mechanisms is important for catalyst design and control of reaction *** studies have offered initial insights into the local bifurcation behavior of CO ***,since the bifurcation behavior of CO oxidation is determined by multiple parameters such as temperature,total flux,and CO fraction,it is difficult to predict the global bifurcation behavior in the resulting high-dimensional parameter *** is for this reason that the observed nonlinear phenomena reflect just the local bifurcation features of CO *** this paper,an elementary chemical law(topological invariance) concerning the bifurcation behavior of CO oxidation on platinum group metals such as Pd(111) is found from a topological *** the elementary law,we put forward a topological approach to model the critical criteria for the reaction hysteresis and *** model may be applied to predict the global bifurcation behavior of CO oxidation in the high-dimensional parameter *** topological approach and the model results may be useful as a guide in thinking about the complex reaction mechanism,designing reaction routes,and actively controlling the bifurcation behavior of the CO oxidation reaction.

关键词： CO oxidation bifurcation hysteresis

Leaf N and P stoichiometry of 57 plant species in the Karamori Mountain Ungulate Nature Reserve,Xinjiang,China

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Journal of Arid Land 2016年第6期8卷 935-947页

作者： tao Ye WU Ganlin ZHANG Yuanming ZHOU xiaobing College of Life Sciences The Province Key Laboratory of the Biodiversity Study and Ecology Conservation in Southwest AnhuiAnqing Normal University Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences

Nitrogen （N） and phosphorus （P） are the major nutrients that constrain plant growth and development, as well as the structure and function of ecosystems. Hence, leaf N and P patterns can contribute to a deep understanding of plant nutrient status, nutrient limitation type of ecosystems, plant life-history strategy and differentiation of functional groups. However, the status and pattern of leaf N and P stoichiometry in N-deficiency desert ecosystems remain unclear. Under this context, the leaf samples from 57 plant species in the Karamori Mountain Ungulate Nature Reserve, eastern Junggar Desert, China were investigated and the patterns and interrelations of leaf N and P were comparatively analyzed. The results showed that the average leaf N concentration, P concentration, and N：P ratio were 30.81 mg/g, 1.77 mg/g and 17.72, respectively. This study found that the leaf N concentration and N：P ratio were significantly higher than those of studies conducted at global, national and regional scales; however, the leaf P concentration was at moderate level. Leaf N concentration was allometrically correlated with leaf P and N：P ratio across all species. Leaf N, P concentrations and N：P ratio differed to a certain extent among plant functional groups. C4 plants and shrubs, particularly shrubs with assimilative branches, showed an obviously lower P concentration than those of C3 plants, herbs and shrubs without assimilative branches. Shrubs with assimilative branches also had lower N concentration. Fabaceae plants had the highest leaf N, P concentrations （as well as Asteraceae） and N：P ratio; other families had a similar N, P-stoichiometry. The soil in this study was characterized by a lack of N （total N：P ratio was 0.605）, but had high N availability compared with P （i.e. the available N：P ratio was 1.86）. This might explain why plant leaves had high N concentration （leaf N：P ratio〉16）. In conclusion, the desert plants in the extreme environment in this study have formed thei

关键词： leaf stoichiometry desert plant functional group nutrient limitation Junggar Desert Karamori Mountain

A systematic design of multifunctional lattice structures with energy absorption and phononic bandgap by topology and parameter optimization

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International Journal of Smart and Nano Materials 2023年第3期14卷 265-285页

作者： Hongling Ye Wenjie Shen Weiwei Wang Ran tao Faculty of Materials and Manufacturing Beijing University of TechnologyBeijingPRChina College of Engineering Peking UniversityBeijing 100871PR China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijingPRChina

Lattice structure can realize excellent multifunctional charac-teristics because of its huge design space,and the cellular configuration directly affects the lattice structural performance and lightweight.A novel energy-absorbing multifunctional lat-tice structure with phononic bandgap is presented by topol-ogy and parameter optimization in this ***,the two-dimensional(2D)cellular configuration is lightweight designed by using independent continuous mapping(ICM)topology optimization *** 2D cell is reconstructed by geo-metric parameters and rotated into a three-dimensional(3D)cell by using chiral shape to achieve ***,the surrogated model with energy absorption as the object and first-order natural frequency as the constraint is estab-lished to optimize a parametric 3D cell based on the Response Surface Methodology(RSM).Finally,the lattice struc-tures are assembled with dodecagonal staggered arrange-ments to avoid the deformation interference among the adjacent *** addition,the lattice structural energy absorp-tion and bandgap characteristics are analyzed and *** to Kelvin lattice structure,the optimal lattice struc-ture shows significant improvement in energy absorption ***,the proposed design also performs well in damping characteristics of the high-frequency and *** lattice structural optimization design framework has great meaning to achieve the equipment structural light-weight and multi-function in the aerospace field.

关键词： Multifunctional lattice structure energy absorption phononic bandgap topology optimization parameter optimization

Lame Function and Its Application to Some Nonlinear Evolution Equations

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Communications in Theoretical Physics 2003年第1X期40卷 53-56页

作者： FUZun-tao LIUShi-Kuo LIUShi-Da ZHAOQiang LSchoolofPhysics PekingUniversityBeijing100871China StateKeyLaboratoryforTurbulenceandComplexSystem DepartmentofMechanicsandEngineeringSciencePekingUniversityBeijing100871China

In this paper, based on the Lame function and Jacobi emptic function, the perturbation method is appliedto some nonlinear evolution equations to derive their multi-order solutions.

关键词：非线性演变方程多次解微扰方法雅可比椭圆函数拉梅函数 Lame函数 Jacobi椭圆函数

Theoretical modeling of the effects of temperature and moisture content on the acoustic velocity of Pinus resinosa wood

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Journal of Forestry Research 2018年第2期29卷 532-539页

作者： Shan Gao Xinmin tao Xiping Wang Lihai Wang Northeast Forestry University Harbin 150040People’s Republic of China USDA Forest Products Laboratory MadisonWI 53745USA

To investigate the effects of temperature and moisture content(MC) on acoustic wave velocity(AWV)in wood,the relationships between wood temperature,MC,and AWV were theoretically *** to the theoretical propagation characteristics of the acoustic waves in the wood mixture and the differences in velocity among various media(including ice,water,pure wood or oven-dried wood),theoretical relationships of temperature,MC,and AWV were established,assuming that the samples in question were composed of a simple mixture of wood and water or of wood and *** the theoretical model,the phase transition of AWV in green wood near the freezing point(as derived from previous experimental results) was plausibly *** comparative analysis between theoretical and experimental models for American red pine(Pinus resinosa) samples,it was established that the theoretically predicted AWV values matched the experiment results when the temperature of the wood was below the freezing point of water,with an averageprediction error of 1.66%.The theoretically predicted AWV increased quickly in green wood as temperature decreased and changed suddenly near 0 °C,consistent with the experimental *** prediction error of the model was relatively large when the temperature of the wood was above the freezing point,probably due to an overestimation of the effect of the liquid water content on the acoustic velocity and the limited variables of the *** high correlation between the predicted and measured acoustic velocity values in frozen wood samples revealed the mechanisms of temperature,MC,and water status and how these affected the wood(particularly its acoustic velocity below freezing point of water).This result also verified the reliability of a previous experimental model used to adjust for the effect of temperature during field testing of trees.

关键词： Acoustic velocity Wood Temperature Moisture content Theoretical model

Numerical analysis of submarine landslides using a smoothed particle hydrodynamics depth integral model

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Acta Oceanologica Sinica 2016年第5期35卷 134-140页

作者： WANG Zhongtao LI Xinzhong LIU Peng tao Yanqi State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China General Research Institute of China National Offshore Oil Corporation Beijing 100010 China

Submarine landslides can cause severe damage to marine engineering structures. Their sliding velocity and runout distance are two major parameters for quantifying and analyzing the risk of submarine ***, commercial calculation programs such as BING have limitations in simulating underwater soil movements. All of these processes can be consistently simulated through a smoothed particle hydrodynamics（SPH） depth integrated model. The basis of the model is a control equation that was developed to take into account the effects of soil consolidation and erosion. In this work, the frictional rheological mode has been used to perform a simulation study of submarine landslides. Time-history curves of the sliding body＇s velocity, height,and length under various conditions of water depth, slope gradient, contact friction coefficient, and erosion rate are compared; the maximum sliding distance and velocity are calculated; and patterns of variation are *** findings of this study can provide a reference for disaster warnings and pipeline route selection.

关键词： sliding velocity runout distance smoothed particle hydrodynamics depth integral method frictional rheological model erosion effect

Coupling Mechanism of Rural Settlements and Mountain Disasters in the Upper Reaches of Min River

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Journal of Mountain Science 2014年第1期11卷 66-72页

作者： DING Ming-tao CHENG Zun-lan WANG Qing School of Environment and Resources Southwest University of Science and Technology Institute of Mountain Hazards and Environment Chinese Academy of Sciences

Human settlements are the place where human beings live,among which the rural settlements can be regarded as a reflection of human-land relationship in mountain areas because their vertical distribution is greatly influenced by the specific geographical environment and ecological conditions of *** on field investigation,this paper uses physical,geographical,and ecological theories to make a comprehensive study of rural settlements and mountain disasters in the upper Min River,which is an ecologically fragile area with high-frequency disasters(collapse,landslide,debris flow,etc.) and a minority inhabit *** applying these modern scientific theories,this paper attempts to shed some light on the relationship between rural settlements and mountain ***,an in-depth understanding of this relationship was achieved as follows:(1) Rural settlements and mountain disasters are mainly distributed in the intercepted flows of water and soil; and both quantity and quality of arable lands in mountains are important indicators of these flows.(2) The Small Watershed Management Project is a complex system of rural settlements and mountain disasters that interacts with and constrains the ecological *** this project,the human survival will be better *** fundamental for the ecological reconstruction,the coupling mechanism of rural settlements and mountain disasters is not only an engine to promote harmonious development between human and nature,but also a bridge to link them.

关键词： The upper reaches of Min River Mountain disaster Rural settlement Coupling mechanism Remote sensing