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Journal of Systems Science and Systems engineering 2001年第4期13卷 409-417页

作者： QIN Ming-zhou1, ZHAO Shu-mao2.1. college of Environment and Planning, Henan University, Kadeng 475001, china 2. Planning Council of Henan Province, {2. 450003, china college of Environment and Planning Henan UniversityKaifeng 475001 China Planning Council of Henan Province Zhengzhou 450003 China

Based on the system theory, this paper discusses the structure and efficiency of agricuItural land use in Kaifeng Suburban. Such present problems as benefit deviation from resource al1ocation, distinguished unemployment and four kinds of contribution of urban agriculture land use are revealed. Then, in the view of sustainab1e development, some resolution measures to the problems are advanced out. These suggestions include farmland protection, ecological agriculture, sustainable land use and input decrease of synthetic matter.

关键词： suburban agricultural land use resources allocation use efficiency farmland protection ecological agriculture

A two-dimensional study on natural convection and heat transfer in the enclosure with heat transfer and radiation coupled in natural convection

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Science china(Technological Sciences) 2010年第4期53卷 991-999页

作者： ZHAN NaiYan1,2.YANG Mo1 & XU PeiWei2.1 college of Power engineering,University of Shanghai for Science and Technology,Shanghiai 2.0093,{2. 2.Department of Environmental engineering,Jilin Architectural and civil engineering Institute,Changchun 13002.,{2. college of Power engineering University of Shanghai for Science and Technology Shanghiai China Department of Environmental engineering Jilin Architectural and Civil Engineering Institute Changchun China

Numerical investigation using SIMPLE algorithm with QUICK scheme for natural convection and heat transfer in the enclosure bounded by a solid wall and with heat transfer and radiation coupled in natural convection has been *** various parameters are:Rayleigh number(from 103 to 105),dimensionless conductivity of bounding wall(from 0 to 100),dimensionless wall thickness(from 0 to 0.6) and radiation emissivity of all surfaces(from 0 to 1).The results suggest that flow and heat transfer are influenced by *** is a dominant action on flow and heat *** increase of the thermal conductivity of wall,flow and heat transfer turn *** temperature distribution changes *** the thermal conductivity of wall is over a certain critical number,the increasing trend of flow and heat transfer may *** increase of enclosure wall thickness,flow and heat transfer turn *** the enclosure wall thickness is over a certain critical number,the flow and heat transfer will turn slow.

关键词： conduction natural convection radiation couple numerical simulation

On Form Invariance,Lie Symmetry and Three Kinds of Conserved Quantities of Generalized Lagrange's Equations

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Communications in Theoretical Physics 2007年第7期48卷 37-42页

作者： ZHAO Shu-Hong LIANG Li-Fuoi School of civil engineering,Harbin engineering University,Harbin 150001,china2.engineering college,Northeast Agricultural University,Harbin 150030,china School of civil engineering Harbin Engineering University Harbin 150001 China engineering college Northeast Agricultural University Harbin 150030 China

In this paper,the form invariance and the Lie symmetry of Lagrange's equations for nonconservativesystem in generalized classical mechanics under the infinitesimal transformations of group are studied,and the Noether'sconserved quantity,the new form conserved quantity,and the Hojman's conserved quantity of system are derived ***,an example is given to illustrate the application of the result.

关键词： form invariance Lie symmetry conserved quantity generalized classical mechanics Lagrange’s equation

Role of ethylene signaling in the production of rice volatiles induced by the rice brown planthopper Nilaparvata lugens

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Science Bulletin 2006年第20期51卷 2457-2465页

作者： LU Yujie1,2. WANG Xia1, LOU Yonggen1 & CHENG Jiaan1 1. Institute of Insect Sciences, Zhejiang University, Hangzhou 31002., china 2. college of Food and Oil, Henan University of Technology, {2. 450052. china Institute of Insect Sciences Zhejiang University Hangzhou China college of Food and Oil Henan University of Technology Zhengzhou China

Ethylene signaling pathway plays an important role in induced plant direct defense against herbivores and pathogens; however, up to now, only few researches have focused on its role in induced plant indirect defense, i.e. the release of herbi- vore-induced volatiles, and the results are variable. Using a model system consisting of rice plants, the rice brown planthopper Nilaparvata lugens and its egg parasitoid Anagrus nilaparvatae, we examined the role of ethylene signaling in the production of rice volatiles induced by N. lugens by measuring both the timing of herbivore-induced ethylene levels and the relationships between ethylene, rice volatiles and attraction of the parasitoid. N. lugens infestation sig- nificantly enhanced the release of ethylene during 2.2. h after infestation. Plants treated with eth- ephon, a compound that breaks down to release ethylene at cytoplasmic pH, released volatiles profiles similar to those released by N. lugens-infested plants, and both of them showed an equal attraction of the parasitoid. Moreover, pretreatment with 1-MCP, an inhibitor of ethylene perception, reduced the release of most of rice volatiles whose amount was enhanced by N. lugens infestation and decreased the attrac- tiveness to the parasitoid. These results demonstrate that ethylene signaling is required for the production of rice volatiles induced by N. lugens.

关键词： ethylene signaling pathway Nilaparvata lugens Anagrus nilaparvatae herbivore-induced rice volatiles rice tritrophic inter- action.

Vision navigation algorithm for mine agent based on quaternion

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中国有色金属学会会刊：英文版 2011年第S3期21卷 610-615页

作者： LI Ke-zhao1, 4, LEI Wei-wei1, 2. GUO Zeng-zhang1, 2. WU Li-xin3, ZHANG Qin4 1. School of Survey and Land Information engineering, Henan Polytechnic University, Jiaozuo 454003, china 2. Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic University, Jiaozuo 454003, china 3. college of Resources and civil engineering, Northeastern University, Shenyang 110819, china 4. college of Geology engineering and Geomatics, Chang’an University, Xi’an 710054, china School of Survey and Land Information engineering Henan Polytechnic University Jiaozuo 454003 China college of Geology engineering and Geomatics Chang'an University Xi'an 710054 China Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping Henan Polytechnic University Jiaozuo 454003 China college of Resources and civil {2. Northeastern University Shenyang 110819 China

Autonomous relative navigation is the key technology in mining or rescuing. On the basis of mine requirement and the theories of machine vision, an autonomous relative navigation algorithm for mine agent based on quaternion was proposed. In rotation transformation, this algorithm was represented by using quaternion. Because the Jacobi matrix of this method is lower than that of Hall algorithm, the calculation efficiency is improved by using this algorithm. The results of these experiments show that the computation burden of this algorithm based on quaternion is about half that of Hall algorithm. This algorithm based on quaternion is improved as a valid way to solve the problem of mine real-time navigation.

关键词： quaternion mine agent vision navigation

Non-linear buffeting response analysis of long-span suspension bridges with central buckle

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Earthquake engineering and engineering Vibration 2010年第2期9卷 259-270页

作者： Wang Hao1,2.Li Aiqun1,Zhao Gengwen1 and Li Jian2.1.college of civil {2.,Southeast University,Nanjing 2.0096,china 2.civil and Environmental {2.,University of Illinois at Urbana-Champaign,Urbana,IL 61801,USA college of civil {2. Southeast University Nanjing China civil and Environmental engineering University of Illinois at Urbana-Champaign Urbana USA

The rigid central buckle employed in the Runyang Suspension Bridge (RSB) was the first time it was used in a suspension bridge in china. By using a spectral representation method and FFT technique combined with measured data,a 3D fluctuating wind field considering the tower wind effect is simulated. A novel FE model for buffeting analysis is then presented,in which a specific user-defined Matrix2. element in ANSYS is employed to simulate the aeroelastic forces and its stiffness or damping matrices are parameterized by wind velocity and vibration frequency. A nonlinear time history analysis is carried out to study the influence of the rigid central buckle on the wind-induced buffeting response of a long-span suspension bridge. The results can be used as a reference for wind resistance design of long-span suspension bridges with a rigid central buckle in the future.

关键词： suspension bridge buffeting response central buckle nonlinear time history analysis ANSYS

聚乙烯醇纤维掺量对高延性地聚合物混凝土早期抗裂和收缩性能影响

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大连理工大学学报 2024年第1期64卷 74-81页

作者：李杉周郑州卢亦焱王喆安俊澎武汉大学土木建筑工程学院湖北武汉430072

研究了聚乙烯醇(PVA)纤维掺量对高延性地聚合物混凝土早期塑性收缩开裂、干燥收缩和自生收缩的影响.结果表明,与地聚合物混凝土相比,掺PVA纤维的高延性地聚合物混凝土抗开裂性能和抗收缩性能显著提高,PVA纤维体积掺量为2.的地聚合物混... 详细信息

研究了聚乙烯醇(PVA)纤维掺量对高延性地聚合物混凝土早期塑性收缩开裂、干燥收缩和自生收缩的影响.结果表明,与地聚合物混凝土相比,掺PVA纤维的高延性地聚合物混凝土抗开裂性能和抗收缩性能显著提高,PVA纤维体积掺量为2.的地聚合物混凝土抗开裂和抗收缩性能最好.基于试验结果,建立了收缩预测模型,该模型能够一定程度反映地聚合物混凝土早期收缩特征.

关键词：地聚合物混凝土高延性塑性收缩开裂干燥收缩自生收缩收缩预测模型

The gravitational gradient tensor’s invariants and the related boundary conditions

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Science china Earth Sciences 2010年第5期53卷 781-790页

作者： YU JinHai1,2.3 & ZHAO DongMing4 1 college of Earth Science, Graduate University of Chinese Academy of Sciences, Beijing 100049, china 2.Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, china 3 State Key Laboratory of Astronautic Dynamics, Xi’an 710043, china 4 zhengzhou Institute of Surveying and Mapping, zhengzhou 450052. china college of Earth Science Graduate University of Chinese Academy of Sciences Beijing China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China State Key Laboratory of Astronautic Dynamics Xi’an China zhengzhou Institute of Surveying and Mapping Zhengzhou China

Here we report new approaches of recovering the Earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2.term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2.2.T), which is approximately equivalent to O(T2.. Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 2.0, and the models with regard to effect of J2.term have accuracies of 10-8 and the order can reach up to 2.0.

关键词： the Earth’s gravitational field gravitational gravidiometry tensor’s invariant

Three-dimensional elasticity solution of simple-supported rectangular plate on point supports, line supports and elastic foundation

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Science china(Technological Sciences) 2009年第3期52卷 584-589页

作者： XU YePeng1 & ZHOU Ding2.1 School of Science, Nanjing University of Science and Technology, Nanjing 2.0094, china 2.college of {2. engineering, Nanjing University of Technology, Nanjing 2.0009, china School of Science Nanjing University of Science and Technology Nanjing China college of civil {2. Nanjing University of Technology Nanjing China

This paper studies the bending of simple-supported rectangular plate on point supports, line supports and elastic foundation. On the basis of three-dimensional elasticity theory, the exact expressions of the displacement functions, which satisfy the governing differential equations and the simply supported boundary conditions at four edges of the plate, are analytically derived. The reaction forces of the in- termediate supports are regarded as the unknown external forces acting on the lower surface of the plate. The unknown coefficients are then determined by the boundary conditions on the upper and lower surfaces of the plate. Comparing the numerical results obtained from the proposed method to those obtained from Kirchhoff plate theory, Mindlin plate theory and those obtained from the commer- cial finite element software ANSYS, the high accuracy of the present method has been demonstrated.

关键词： rectangular plate point support line support elastic foundation displacement stress three-dimensional elasticity solution

Fuzzy Approach to Determining Priority Preorders of Water Resources Projects

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Transactions of Tianjin University 2009年第2期15卷 121-125页

作者：刘英杰冯平 School of civil engineering Tianjin University civil engineering Supervisor Center North China Institute of Water Conservancy and Hydroelectric Power

In this paper,the criteria set related to the priority preorders of water resources projects is introduced.A fuzzy multiple criteria group decision-making model is established,which incorporates quantitative analysis,judgments,experience and preferences of *** model is used in practice to determine the priority preorders of five water resources projects,and the results show that the best choice can supply more new employment,domestic water and irrigation water,and has better quality.

关键词： fuzzy decision-making priority preorders water resources projects