The equation of two-dimensional fiber direction vector was solved theoretically to give the fiber orientation distri- bution in simple shear flow, flow with two direction shears, extensional flow and arbitrary planar ...The equation of two-dimensional fiber direction vector was solved theoretically to give the fiber orientation distri- bution in simple shear flow, flow with two direction shears, extensional flow and arbitrary planar incompressible flow. The Fok- ker-Planck equation was solved numerically to validify the theoretical solutions. The stable orientation and orientation period of fiber were obtained. The results showed that the fiber orientation distribution is dependent on the relative not absolute magnitude of the matrix rate-of-strain of flow. The effect of fiber aspect ratio on the orientation distribution of fiber is insignificant in most conditions except the simple shear case. It was proved that the results for a planar flow could be generalized to the case of 3-D fiber direction vector.展开更多
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
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
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
Currently, the cruise market in North America is almost saturated and that in Europe is restricted by the scale. However, the cruise market prospect in East Asia is broad due to the deep cultural heritage, abundant to...Currently, the cruise market in North America is almost saturated and that in Europe is restricted by the scale. However, the cruise market prospect in East Asia is broad due to the deep cultural heritage, abundant tourism resources and large population base, resulting in the shift of the global cruise industry eastward to Asia. The position of Asia in the global cruise economy has become prominent increasingly. As a part of Shanghai, one of the most economically powerful coastal cities in China, Baoshan has national leading land, sea and air transportation networks, huge passenger flow and natural deep water terminals. Therefore, Shanghai steps in front in the development of cruise economy, shouldering the responsibility of a leader in the development of the national cruise industry. It will accelerate the growth of Shanghai's cruise industry to plan and construct the "cruise town" in Baoshan. In this paper, the author aims to further analyze the current construction orientation and development goal of the cruise town by studying the industrial base and analyzing the environment for the cruise town construction in Baoshan, explore the industrial distribution for the construction and development of the cruise town from the perspectives of tourism industry, leisure industry, finance and other service industries, and information industry, conduct in-depth analysis on the ideas about industrial distribution, and determine the system guarantee for industrial development so as to promote the healthy and orderly development of the cruise industry in China.展开更多
The algorithm for evaluation of fiber orientation distribution function (ODF) by laser scattering method based on 2 - dimentional model of fiber arrangement and the method of determining diffuse scattering intensity a...The algorithm for evaluation of fiber orientation distribution function (ODF) by laser scattering method based on 2 - dimentional model of fiber arrangement and the method of determining diffuse scattering intensity are presented. The fiber ODFs of nonwoven samples measured by the computer-program-controlled laser scattering intensity testing system are compared with that of the data obtained by microprojector method. The results show that the algorithm is feasible for assessing the fiber ODFs of nonwoven fabrics manufactured by different processing methods.展开更多
The distribution function and orientation tensor of fiber suspensions in wedge shaped flow field were computed . The results indicate that with time increasing, the fiber orient themselves to flow direction graduall...The distribution function and orientation tensor of fiber suspensions in wedge shaped flow field were computed . The results indicate that with time increasing, the fiber orient themselves to flow direction gradually. At the locations with same pole radii, the angle between fiber orientation and centerline, which occurs with the most probability, decreases with the pole angle increasing . At the locations with same pole angle, the angle between fiber orientation and centerline increases with the pole radii decreasing. The second order tensors get steady more quickly at the points where the velocity g radients are larger. At the locations with same pole angle, the steady values of orientation tensors are identical. At the locations with same pole radii is, streamline becomes flatter as the pole angle decreases.展开更多
本文应用ODF(Orientatien Distribution Function)的方法定量测定了含磷低碳深冲钢热轧、冷轧、退火各工序及样品各层次的织构,研究钢的织构转变。结果表明,①热轧织构主要类型为{100}<011>,冷轧织构主要由<110>//R、D的α...本文应用ODF(Orientatien Distribution Function)的方法定量测定了含磷低碳深冲钢热轧、冷轧、退火各工序及样品各层次的织构,研究钢的织构转变。结果表明,①热轧织构主要类型为{100}<011>,冷轧织构主要由<110>//R、D的α-纤维织构和{111}//N、D的γ-纤维织构组成并以{112}<110>织构最强;经退火后{112}<110>织构转化为{111}<112>织构,并形成很强的有利深冲的{111}面织构;②冷轧板各层织构强弱不均,退火后对此不均匀性有一定的继承性。③含磷钢经退火后{111}<112>织构增强可由定向生核、定向长大作用及AlN在晶界析出解释。展开更多
This paper is concerned with a method for forming distributed measurement and control system.A three-layer structure model based on network,physical node layer and func-tion node layer is discussed.It is designed on o...This paper is concerned with a method for forming distributed measurement and control system.A three-layer structure model based on network,physical node layer and func-tion node layer is discussed.It is designed on object-oriented software method.The model has a fine application prospect.展开更多
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
基金Project (No. 10372090) supported by the National Natural Science Foundation of China
文摘The equation of two-dimensional fiber direction vector was solved theoretically to give the fiber orientation distri- bution in simple shear flow, flow with two direction shears, extensional flow and arbitrary planar incompressible flow. The Fok- ker-Planck equation was solved numerically to validify the theoretical solutions. The stable orientation and orientation period of fiber were obtained. The results showed that the fiber orientation distribution is dependent on the relative not absolute magnitude of the matrix rate-of-strain of flow. The effect of fiber aspect ratio on the orientation distribution of fiber is insignificant in most conditions except the simple shear case. It was proved that the results for a planar flow could be generalized to the case of 3-D fiber direction vector.
文摘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.
文摘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.
文摘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.
文摘Currently, the cruise market in North America is almost saturated and that in Europe is restricted by the scale. However, the cruise market prospect in East Asia is broad due to the deep cultural heritage, abundant tourism resources and large population base, resulting in the shift of the global cruise industry eastward to Asia. The position of Asia in the global cruise economy has become prominent increasingly. As a part of Shanghai, one of the most economically powerful coastal cities in China, Baoshan has national leading land, sea and air transportation networks, huge passenger flow and natural deep water terminals. Therefore, Shanghai steps in front in the development of cruise economy, shouldering the responsibility of a leader in the development of the national cruise industry. It will accelerate the growth of Shanghai's cruise industry to plan and construct the "cruise town" in Baoshan. In this paper, the author aims to further analyze the current construction orientation and development goal of the cruise town by studying the industrial base and analyzing the environment for the cruise town construction in Baoshan, explore the industrial distribution for the construction and development of the cruise town from the perspectives of tourism industry, leisure industry, finance and other service industries, and information industry, conduct in-depth analysis on the ideas about industrial distribution, and determine the system guarantee for industrial development so as to promote the healthy and orderly development of the cruise industry in China.
基金This project is supported by Key Subject Foundation of Shanghai Educational Committee.
文摘The algorithm for evaluation of fiber orientation distribution function (ODF) by laser scattering method based on 2 - dimentional model of fiber arrangement and the method of determining diffuse scattering intensity are presented. The fiber ODFs of nonwoven samples measured by the computer-program-controlled laser scattering intensity testing system are compared with that of the data obtained by microprojector method. The results show that the algorithm is feasible for assessing the fiber ODFs of nonwoven fabrics manufactured by different processing methods.
基金Project supported by the National Natural Science Foundation for Outstanding Youth of China. (Grant No: 19925210)
文摘The distribution function and orientation tensor of fiber suspensions in wedge shaped flow field were computed . The results indicate that with time increasing, the fiber orient themselves to flow direction gradually. At the locations with same pole radii, the angle between fiber orientation and centerline, which occurs with the most probability, decreases with the pole angle increasing . At the locations with same pole angle, the angle between fiber orientation and centerline increases with the pole radii decreasing. The second order tensors get steady more quickly at the points where the velocity g radients are larger. At the locations with same pole angle, the steady values of orientation tensors are identical. At the locations with same pole radii is, streamline becomes flatter as the pole angle decreases.
文摘本文应用ODF(Orientatien Distribution Function)的方法定量测定了含磷低碳深冲钢热轧、冷轧、退火各工序及样品各层次的织构,研究钢的织构转变。结果表明,①热轧织构主要类型为{100}<011>,冷轧织构主要由<110>//R、D的α-纤维织构和{111}//N、D的γ-纤维织构组成并以{112}<110>织构最强;经退火后{112}<110>织构转化为{111}<112>织构,并形成很强的有利深冲的{111}面织构;②冷轧板各层织构强弱不均,退火后对此不均匀性有一定的继承性。③含磷钢经退火后{111}<112>织构增强可由定向生核、定向长大作用及AlN在晶界析出解释。
文摘This paper is concerned with a method for forming distributed measurement and control system.A three-layer structure model based on network,physical node layer and func-tion node layer is discussed.It is designed on object-oriented software method.The model has a fine application prospect.
基金Acknowledgements: This work is supported in part by the National Natural Science Foundation of China (No. 60503020), the Natural Science Research Plan for Jiangsu High School (No 05KJD520151), and 0pening Foundation of Jiangsu Key Laboratory of Computer Information Processing Technology in Soochow University, Guangxi Natural Science Foundation of China (No. 0542036).
基金supported by the National Natural Science Foundation of China (10562004, 10662004)the Jiangxi Project to Nurture Academic and Technical Leaders in Targeted Areas+1 种基金the Research Fund for the Docotoral Program of Higher Education (20070403003)the Natural Science Foundation of Jiangxi of China (2008GZW0005).
文摘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.