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Analysis on Function Orientation and Development Countermeasures of New Agricultural Business Entities 被引量:1
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作者 Wang Yang Wang Yan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第2期82-88,共7页
Along with the rapid advance of industrialization and urbanization process, fostering new agricultural business entities become inevitable for agricultural transformation and the construction of agricultural moderniza... Along with the rapid advance of industrialization and urbanization process, fostering new agricultural business entities become inevitable for agricultural transformation and the construction of agricultural modernization in China. The status of the new agricultural business entities determines the level of modern agricultural development. In recent years, new agricultural business entities have grew rapidly. However, there are still many problems including the difficulties in financing loans, inadequate agricultural insurance system, bad implementation of agricultural subsidies, jagged agricultural talents and so on. In order to foster new agricultural business entities, countermeasures should be carried out to ensure financial support, perfect the agricultural insurance, strengthen the level of agricultural subsidies, strive to develop the degree of specialization agricultural operators and so on. 展开更多
关键词 new type agricultural business entities restrictive factor function orientation
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ORIENTATION DISTRIBUTION FUNCTIONS FOR MICROSTRUCTURES OF HETEROGENEOUS MATERIALS (Ⅰ) ──DIRECTIONAL DISTRIBUTION FUNCTIONS AND IRREDUCIBLE TENSORS
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作者 ZHENG Quan-shui(郑泉水) +1 位作者 ZOU Wen-nan(邹文楠) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第8期865-884,共20页
In this two_part paper, a thorough investigation is made on Fourier expansions with irreducible tensorial coefficients for orientation distribution functions (ODFs) and crystal orientation distribution functions (CODF... In this two_part paper, a thorough investigation is made on Fourier expansions with irreducible tensorial coefficients for orientation distribution functions (ODFs) and crystal orientation distribution functions (CODFs), which are scalar functions defined on the unit sphere and the rotation group, respectively. Recently it has been becoming clearer and clearer that concepts of ODF and CODF play a dominant role in various micromechanically_based approaches to mechanical and physical properties of heterogeneous materials. The theory of group representations shows that a square integrable ODF can be expanded as an absolutely convergent Fourier series of spherical harmonics and these spherical harmonics can further be expressed in terms of irreducible tensors. The fundamental importance of such irreducible tensorial coefficients is that they characterize the macroscopic or overall effect of the orientation distribution of the size, shape, phase, position of the material constitutions and defects. In Part (Ⅰ), the investigation about the irreducible tensorial Fourier expansions of ODFs defined on the N_dimensional (N_D) unit sphere is carried out. Attention is particularly paid to constructing simple expressions for 2_ and 3_D irreducible tensors of any orders in accordance with the convenience of arriving at their restricted forms imposed by various point_group (the synonym of subgroup of the full orthogonal group) symmetries. In the continued work -Part (Ⅱ), the explicit expression for the irreducible tensorial expansions of CODFs is established. The restricted forms of irreducible tensors and irreducible tensorial Fourier expansions of ODFs and CODFs imposed by various point_group symmetries are derived. 展开更多
关键词 orientation distribution function irreducible tensor tensorial Fourier expansion heterogeneous material MICROSTRUCTURE
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ORIENTATION DISTRIBUTION FUNCTIONS FOR MICROSTRUCTURES OF HETEROGENEOUS MATERIALS (Ⅱ)──CRYSTAL DISTRIBUTION FUNCTIONS AND IRREDUCIBLE TENSORS RESTRICTED BY VARIOUS MATERIAL SYMMETRIES
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作者 ZHENG Quan-shui(郑泉水) +1 位作者 FU Yi-bin(傅依斌) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第8期885-903,共19页
The explicit representations for tensorial Fourier expansion of 3_D crystal orientation distribution functions (CODFs) are established. In comparison with that the coefficients in the mth term of the Fourier expansion... The explicit representations for tensorial Fourier expansion of 3_D crystal orientation distribution functions (CODFs) are established. In comparison with that the coefficients in the mth term of the Fourier expansion of a 3_D ODF make up just a single irreducible mth_order tensor, the coefficients in the mth term of the Fourier expansion of a 3_D CODF constitute generally so many as 2m+1 irreducible mth_order tensors. Therefore, the restricted forms of tensorial Fourier expansions of 3_D CODFs imposed by various micro_ and macro_scopic symmetries are further established, and it is shown that in most cases of symmetry the restricted forms of tensorial Fourier expansions of 3_D CODFs contain remarkably reduced numbers of mth_order irreducible tensors than the number 2m+1 . These results are based on the restricted forms of irreducible tensors imposed by various point_group symmetries, which are also thoroughly investigated in the present part in both 2_ and 3_D spaces. 展开更多
关键词 crystal orientation distribution function irreducible tensor Fourier expansion microstructure material symmetry
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NUMERICAL SIMULATION OF ORIENTATION DISTRIBUTION FUNCTION OF CYLINDRICAL PARTICLE SUSPENSIONS
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作者 LIN Jian-zhong(林建忠) +1 位作者 ZHANG Ling-xin(张凌新) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第8期906-912,共7页
The orientation distribution function of cylindrical particle suspensions was deduced and numerically simulated, and an application was taken in a wedge-shaped flow field. The relationship between the orientation dist... The orientation distribution function of cylindrical particle suspensions was deduced and numerically simulated, and an application was taken in a wedge-shaped flow field. The relationship between the orientation distribution function and particle orientation angles was obtained. The results show that comparing with the most probable angle distribution which comes to being in short time, the distribution of the steady state doesn't vary much. in range; the main difference is the anti-clockwise rotation in the right and upper field, that is, particles rotate more at the points where the velocity gradients are larger. The most probable orientations are close to the direction of local streamlines. In the direction of streamlines, with poleradius decreasing, the most probable angles increase, but the angles between their orientations and the local streamlines decrease. 展开更多
关键词 cylindrical particle suspension wedge-shaped flow orientation distribution function most probable angle numerical simulation
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Influence of Rolling Reductions on Recrystallization Texture in Commercially Pure Al 被引量:6
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作者 毛卫民 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1990年第4期257-262,共6页
The recrystallization texture in commercially pure Al is investigated after the samples are rolled differently and annealed.The samples with low rol- ling reductions could be generally recovered or recrystallized in s... The recrystallization texture in commercially pure Al is investigated after the samples are rolled differently and annealed.The samples with low rol- ling reductions could be generally recovered or recrystallized in situ and characterized by the re- tained G{110}<001>component.This recovery process decreases during annealing with the increase of reduction.The appearance of the B/R{359}. <132>and R{123}<634>components de- pending on the rolling reduction is investigated and the less developed Cube{100}<001>component in commercially pure ahninium is also discussed. 展开更多
关键词 RECRYSTALLIZATION TEXTURE aluminium orientation distribution function (ODF)
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Rethinking about the Formulae of the Relationship between Euler Angles and Texture 被引量:4
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作者 Liangwei Chen Yuyu Hui +2 位作者 Lan Yu Jin Hu Jianhong Yi 《Journal of Harbin Institute of Technology(New Series)》 CAS 2021年第5期70-77,共8页
The formulae of the relationships between Euler angles and texture are important for the orientation distribution functions of research materials.At present,it is found that the formulae for the orthogonal and hexagon... The formulae of the relationships between Euler angles and texture are important for the orientation distribution functions of research materials.At present,it is found that the formulae for the orthogonal and hexagonal crystal structure proposed by Roe and Bunge are not in accord with the normal direction(ND)being perpendicular to the rolling direction(RD).In this paper,these formulae are deduced independently according to the notations proposed by Roe and Bunge.The results show that in addition to the coincidence with the formulae for the cubic crystal structure given by the Roe and Bunge,the other formulae are different from Roe’s and Bunge’s.The new formulae are in accord with ND,RD,and transverse direction(TD)at right angles. 展开更多
关键词 texture Euler space Bunge notation Roe notation orientation distribution function
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Textural Characteristic of 70-30 Brass Rolled by Cross Shear Rolling in Single Direction
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作者 赵骧 刘燕声 +1 位作者 徐家桢 梁志德 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1990年第3期206-210,共5页
70-30 brass is rolled with 90% reduction by cross shear rolling in single direction with speed ra- tio 1.39.The sheet is divided into five layers along rolling plane normal to measure macroscopic statis- tical unsymme... 70-30 brass is rolled with 90% reduction by cross shear rolling in single direction with speed ra- tio 1.39.The sheet is divided into five layers along rolling plane normal to measure macroscopic statis- tical unsymmetric textures in every layer are des- cribed and analysed by means of three dimensional orientation distribution function.The results indi- cate that the main textures in every layer of brass rolled by cross shear rolling in single direction are the same as the main textures of brass rolled by conventional rolling.But the intensities,peak posi- tions and scatters of every texture component in {110}<112>are different,namely,there is a macroscopic statistical unsymmetry.It is found that the textures in every layer of brass rolled by cross shear rolling in single direction can be considered as the textures of brass rolled by common rolling in single direction at identical shear forces,the macroscopic statistical unsymmetry depends on the shear forces which are exerted on the layer. 展开更多
关键词 TEXTURE macroscopic statistical unsymmetry cross shear rolling orientation distribution function
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STUDY OF TEXTURE EFFECT ON STRAIN LOCALIZATION OF BCC STEEL SHEETS
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作者 Eiji Nakamachi 《Acta Mechanica Solida Sinica》 SCIE EI 2000年第2期95-104,共10页
Using elastic crystalline viscoplastic finite element (FE) annlysis, the formability of BCC steel sheets was assessed. An orientation probability assignment method in the FE modeling procedure, which can be categorize... Using elastic crystalline viscoplastic finite element (FE) annlysis, the formability of BCC steel sheets was assessed. An orientation probability assignment method in the FE modeling procedure, which can be categorized as an inhomogenized material modeling, was newly proposed. In the study, the crystal orientations of three materials, mild steel, dual phase steel and the high strength steel, were obtained by Xray diffraction and orientation distribution function (ODF) analyses. The measured ODF results have revealed clearly different textures in the sheets, featured by orientation fibers, skeleton lines and selected orientations in Euler angle space, which are closely related to the plastic anisotropy. Then, the crystal orientations were assigned to FE integration points by using this ODF data, individually. The FE analyses of the standard limiting dome height (LDH) test show how the fiber textures affect the extent of strain localization in the forming processes. It was confirmed by comparison with experimental results that this FE code could predict the extreme strain localization and assess the sheet formability. 展开更多
关键词 crystalline plasticity TEXTURE orientation distribution function strain localization finite element analysis
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PREDICTION OF EARING IN TEXTURED ALUMINIUM SHEETS BASED ON CRYSTAL PLASTICITY
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作者 E. Nakamachi 《Acta Mechanica Solida Sinica》 SCIE EI 2001年第2期95-103,共9页
The phenomenon of earing is investigated in the present studybased on the theory of crystal plasticity with the dynamic explicityfinite element program developed. Firstly texture analysis is carriedout of rolled alumi... The phenomenon of earing is investigated in the present studybased on the theory of crystal plasticity with the dynamic explicityfinite element program developed. Firstly texture analysis is carriedout of rolled aluminum alloy A15052 by means of X-ray technique. Thenfrom the texture coefficients an analytical expression for theorientation distribution function (ODF) is derived making use of thecomputer algebraic language Mathematica4.0, which makes it easier todiscretize the ODF into a series of Eulerian angles repre- sentingthe distribution of lattices and further the preferred orientation(texture) of crystals of the original she- ets. 展开更多
关键词 EARING TEXTURE orientation distribution function(ODF)
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Direction-dependent functions of physical properties for crystals and polycrystals
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作者 Mojia Huang Mengcheng Chen Tenglong Zheng 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第5期639-649,共11页
Some physical properties of crystals differ in direction n because crystal lattices are often anisotropic. A polycrystal is an aggregate of numerous tiny crystallites. Unless the polycrystal is an isotropic aggregate ... Some physical properties of crystals differ in direction n because crystal lattices are often anisotropic. A polycrystal is an aggregate of numerous tiny crystallites. Unless the polycrystal is an isotropic aggregate of crystallites, the physical properties of the polycrystal vary with n. The direction-dependent functions (DDF) for crystals and polycrystals are introduced to describe the variations of the physical properties in direction n. Until now there are few papers dealing systematically with relations between the DDF and the crystalline orientation distribution. Herein we give general expressions of the DDF for crystals and polycrystals. We discuss the applications of the DDF in describing the physical properties of crystals and polycrystals. 展开更多
关键词 Direction-dependent function orientation distribution function Physical properties of crystals and polycrystals
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Measuring the past 20 years of urban-rural land growth in flood-prone areas in the developed Taihu Lake watershed, China 被引量:3
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作者 Weizhong SU 《Frontiers of Earth Science》 SCIE CAS CSCD 2017年第2期361-371,共11页
There is growing interest in using the urban landscape for stormwater management studies, where land patterns and processes can be important controls for the sustainability of urban development and planning. This pape... There is growing interest in using the urban landscape for stormwater management studies, where land patterns and processes can be important controls for the sustainability of urban development and planning. This paper proposes an original index of Major Hazard Oriented Level (MHOL) and investigates the structure distribution, driving factors, and controlling suggestions of urban-rural land growth in flood-prone areas in the Taihu Lake watershed, China. The MHOL of incremental urban-rural land increased from M 31.51 during the years 1985-1995 to M 38.37 during the years 1995-2010 (M for medium structure distribution, and the number for high-hazard value). The index shows that urban-rnraI land was distributed uniformly in flood hazard levels and tended to move rapidly to high-hazard areas, where 72.68% of incremental urban-rural land was aggregated maximally in new urban districts along the Huning traffic line and the Yangtze River. Thus, the current accelerating growth of new urban districts could account for the ampliative exposure to high-hazard areas. New districts are driven by the powerful link between land financial benefits and political achievements for local governments and the past unsustainable process of "single objective" oriented planning. The correlation categorical analysis of the current development intensity and carrying capacity of hydrological ecosystems for sub-basins was used to determine four types of development areas and provide decision makers with indications on the future watershed- scale subdivision of Major Function Oriented Zoning implemented by the Chinese government. 展开更多
关键词 urban-rural land growth flood-prone areas major hazard oriented level major function oriented zoning Taihu Lake Watershed
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Rare earth texture analysis of rectangular extruded Mg alloys and a comparison of different alloying adding ways 被引量:2
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作者 Xiu-Li Hou Yi-Xuan Zhai +3 位作者 Peng Zhang Shun Guo Zhi-Zhong Yuan Qing-Feng Guan 《Rare Metals》 SCIE EI CAS CSCD 2016年第11期850-857,共8页
The microstructures and textures of four rectangular extruded Mg alloys, Mg-3Gd, Mg-3Nd, Mg-1Gd-1Nd and Mg-1.5Gd-1.5Nd(all in wt%) were investigated by using optical microscopy(OM), X-ray diffraction(XRD) and el... The microstructures and textures of four rectangular extruded Mg alloys, Mg-3Gd, Mg-3Nd, Mg-1Gd-1Nd and Mg-1.5Gd-1.5Nd(all in wt%) were investigated by using optical microscopy(OM), X-ray diffraction(XRD) and electron backscatter diffraction(EBSD). The results demonstrate that the extruded alloys all reveal fully recrystallized microstructure and weak non-basal texture.For textures of the four extruded alloys, it is shown that the basal planes of majority grains tilt away from the sheet plane normal toward the extrusion direction. Compared with two binary alloys, the ternary alloys possess weaker texture strengths. Through orientation distribution function analysis, two types of rare earth textures, {0113} 〈0223〉and {1215} 〈1213〉, were found in the extruded alloys.Texture component {1215} 〈1213〉 is relatively weak, but it plays a critical role in the low texture intensities of two ternary alloys. A pairing effect of Gd and Nd elements has an influence on the texture modification. Additionally,there is a difference in the sensitivities of experimental parameters between the microstructure and texture. 展开更多
关键词 Mg alloy Texture Rare earth elements orientation distribution function
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1Chinese human geography and its contributions 被引量:4
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作者 FAN Jie 《Journal of Geographical Sciences》 SCIE CSCD 2016年第8期987-1000,共14页
The aim of this paper is to sift through examples of outstanding contributions made by Chinese human geography in terms of social applications and explain the basic concepts and theoretical methods explored by human g... The aim of this paper is to sift through examples of outstanding contributions made by Chinese human geography in terms of social applications and explain the basic concepts and theoretical methods explored by human geography that are behind the applications of results with major social influence, so as to be able to summarize the main school that represents developments in contemporary Chinese human geography. Chinese human geography upholds the subject's designation as being integrated and interdisciplinary. Research focuses on interactions between the natural and human spheres of the Earth's surface, and it is guided by the understanding and effects of the processes of regional sustainable development at different spatial scales. Chinese human geography has innovatively established the following development paradigm: "To be guided by application requirements, refine key issues of the discipline in the course of solving major issues of human geography in national and regional development, and by solving those key issues, to enhance its ability to provide scientific and technological support to serve national and local needs while promoting its own development." Results from early Chinese human geography studies on land use and agricultural zoning, recent research results on point-axis system models and T-shaped national spatial development patterns, and current research results on territorial function theory and major function oriented zones have all continued and strengthened the mainstream school of Chinese human geography and have avoided the global tendency for human geography to become rapidly human-oriented, while results have been applied at the highest level of decision-making management. Chinese human geography can provide lessons for developing countries and may play a leading role in the future development of global human geography. 展开更多
关键词 Chinese human geography main school social contribution land use agricultural zoning point-axis system T-shaped land development structure territorial function major function oriented zone
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A Kind of Equivalence of Three Nonlinear Scalarization Functions in Vector Optimization
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作者 LI Fei YANG Xinmin 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2021年第2期692-705,共14页
In this paper,by the notions of base functionals and augmented dual cones,the authors indicate firstly that the norms,Gerstewitz functionals and oriented distance functions have common characteristics with base functi... In this paper,by the notions of base functionals and augmented dual cones,the authors indicate firstly that the norms,Gerstewitz functionals and oriented distance functions have common characteristics with base functionals.After that,the equivalence of these three sublinear functions on the ordering cone is established by using the structures of augmented dual cones under the assumption that it has a bounded base.However,the authors show that two superlinear functions do not have similar relations with the norms ahead.More generally,the equivalence of three sublinear functions outside the negative cone has also been obtained in the end. 展开更多
关键词 Base functionals Gerstewitz functionals norms oriented distance functions vector optimization
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Moving Mesh Kinetic Simulation for Sheared Rodlike Polymers with High Potential Intensities
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作者 Yana Di Pingwen Zhang 《Communications in Computational Physics》 SCIE 2006年第5期859-873,共15页
The Doi-Hess equation that describes the evolution of an orientational dis-tribution function is capable of predicting several rheological features of nematic poly-mers.Since the orientational distribution function be... The Doi-Hess equation that describes the evolution of an orientational dis-tribution function is capable of predicting several rheological features of nematic poly-mers.Since the orientational distribution function becomes sharply peaked as poten-tial intensity increases,powerful numerical methods become necessary in the relevant numerical simulations.In this paper,a numerical scheme based on the moving grid techniques will be designed to solve the orientational distribution functions with high potential intensities.Numerical experiments are carried out to demonstrate the effec-tiveness and robustness of the proposed scheme. 展开更多
关键词 orientational distribution function moving mesh method spherical geometry Smolu-chowski equation potential intensity
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Dipole and charge effects of chloroaluminum phthalocyanine revealed by local work function measurements at sub-molecular level
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作者 Huanjun Song Na Li +6 位作者 Hao Zhu Zhantao Peng Wenhui Zhao Haoran Chen Wei Chen Yongfeng Wang Kai Wua 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第3期429-432,共4页
Work function plays a significant role in surface chemistry. Local work function provides the information of local d/pole-d/pole interaction and charge distribution between adsorbates and substrate, highlighting the l... Work function plays a significant role in surface chemistry. Local work function provides the information of local d/pole-d/pole interaction and charge distribution between adsorbates and substrate, highlighting the local charge effect of the targeted spot which is normally smeared out in conventional average work function measurements. Chloroaluminum phthalocyanine (CIA1Pc), an important optoelectronic molecule with a permanent dipole moment pointing from the Pc ring to the ending CI atom, adsorbed on Au(111) in either Cl-up or Cl-down configuration. Scanning tunneling microscopy/spectroscopy measurements revealed that at the centers of Cl-up and CI-down molecules, the local work functions changed oppositely with respect to the Au(111) substrate. At their Pc lobes, however, the local work functions unanimously increased due to charging effect of the indole lobes in the CIAIPc molecule. 展开更多
关键词 Chloroaluminum phthalocyanine Local work function Dipole orientation Scanning tunneling microscopy Surface dipole
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