期刊文献+
共找到128篇文章
< 1 2 7 >
每页显示 20 50 100
Research on the behavior of fiber orientation probability distribution function in the planar flows 被引量:2
1
作者 周锟 林建忠 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第4期257-264,共8页
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
关键词 Fiber suspension flow orientation distribution Probability distribution function
下载PDF
ORIENTATION DISTRIBUTION FUNCTIONS FOR MICROSTRUCTURES OF HETEROGENEOUS MATERIALS (Ⅰ) ──DIRECTIONAL DISTRIBUTION FUNCTIONS AND IRREDUCIBLE TENSORS
2
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
下载PDF
ORIENTATION DISTRIBUTION FUNCTIONS FOR MICROSTRUCTURES OF HETEROGENEOUS MATERIALS (Ⅱ)──CRYSTAL DISTRIBUTION FUNCTIONS AND IRREDUCIBLE TENSORS RESTRICTED BY VARIOUS MATERIAL SYMMETRIES
3
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
下载PDF
NUMERICAL SIMULATION OF ORIENTATION DISTRIBUTION FUNCTION OF CYLINDRICAL PARTICLE SUSPENSIONS
4
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
下载PDF
Research on Functional Orientation and Industrial Distribution of Cruise Town in Baoshan District, Shanghai
5
作者 QIU Ling GAO Changchun 《International English Education Research》 2017年第5期44-47,共4页
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
关键词 SHANGHAI cruise town functional orientation industrial distribution
下载PDF
Measuring Fiber Orientation in Nonwoven Fabrics by Laser Scattering Method Part Ⅱ: Algorithm and Verification
6
作者 周胜 储才元 严灏景 《Journal of Donghua University(English Edition)》 EI CAS 2001年第2期32-36,共5页
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
关键词 fiber orientation distribution Junction laser scattering ALGORITHM VERIFICATION
下载PDF
RESEARCH ON DISTRIBUTION FUNCTION AND ORIENTATION TENSORS OF FIBER SUSPENSIONS IN WEDGE-SHAPED FLOW FIELD 被引量:10
7
作者 Lin, Jian-Zhong Zhang, Ling-Xin Wang, Ye-Long 《Journal of Hydrodynamics》 SCIE EI CSCD 2002年第1期38-44,共7页
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
关键词 fiber suspensions wedge shaped flow distribution function orientation tensors numerical simulation
原文传递
用ODF图的诠释图分析铸轧3004铝合金板织构 被引量:1
8
作者 温熙宇 王玉林 +1 位作者 郑炀曾 李金燕 《东北重型机械学院学报》 CAS 1994年第2期175-179,共5页
本文采用了自编制的立方系取向分布函数(ODF)图的诠释程序,提供了恒的ODF图的诠释图,并且用该诠释图成功地分析了铸轧3O04铝合金板织构状态.
关键词 分布函数 诠释图 铸轧铝合金 织构
下载PDF
取向分布函数(ODF)在材料织构研究中的应用 被引量:2
9
作者 盛捷 李旭东 徐承强 《黑龙江科技学院学报》 CAS 2007年第1期4-7,共4页
为准确描述材料性能,以立方晶体为对象,采用Bunge的级数展开法模型计算其取向分布函数(ODF),以Voronoi增量算法为基础生成多晶体材料各晶粒的几何数据信息,利用可视化手段将多晶体材料晶粒位置与对应的ODF实现可视化,直观显示了多晶体... 为准确描述材料性能,以立方晶体为对象,采用Bunge的级数展开法模型计算其取向分布函数(ODF),以Voronoi增量算法为基础生成多晶体材料各晶粒的几何数据信息,利用可视化手段将多晶体材料晶粒位置与对应的ODF实现可视化,直观显示了多晶体材料中ODF值在各晶粒内的分布。对立方晶系多晶体材料的ODF测算及可视化处理,有助于获得材料的织构类型与分布规律。 展开更多
关键词 材料 宏观织构 微观织构 取向分布函数 欧拉空间 可视化
下载PDF
表征非晶聚合物分子取向分布的ODF分析法 被引量:2
10
作者 韩甫田 宾仁茂 《高分子材料科学与工程》 EI CAS CSCD 北大核心 1995年第2期116-120,共5页
本文对单轴取向非晶聚合物的分子分布状态进行了物理描述和数学表征,详细论证了广角X射线方法测定和计算全取向分布函数ODF(Allorientationdistributionfunction)。在此基础上,用Fortr... 本文对单轴取向非晶聚合物的分子分布状态进行了物理描述和数学表征,详细论证了广角X射线方法测定和计算全取向分布函数ODF(Allorientationdistributionfunction)。在此基础上,用Fortran语言编写计算ODF的ODF92型程序,并用于单轴取向非晶态聚脂(PET)的取向分布分析,获得了令人满意的结果。 展开更多
关键词 取向 非晶聚合物 odf WAXD
下载PDF
ODF测试分析系统 被引量:2
11
作者 蔡明杰 何崇智 《钢铁研究学报》 CAS CSCD 北大核心 1990年第1期87-90,共4页
ODF分析是现代织构材料分析的最有效手段。本文在研制成功ODF测试分析系统的基础上,介绍了系统的工作原理及其功能,并结合测试分析实例说明了ODF分析的应用。
关键词 织构 odf 材料性能
下载PDF
含磷深冲钢的ODF分析 被引量:1
12
作者 潘祜 何崇智 《钢铁研究学报》 CAS CSCD 北大核心 1993年第4期73-77,共5页
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
关键词 织构 含磷深冲钢 odf分析
下载PDF
A Study of Model for Distributed Measurement and Control System 被引量:2
13
作者 张劲 钟毅芳 《微计算机信息》 2003年第9期17-20,共4页
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
关键词 分布式测控系统 面向对象 框架模型 软件方法 网络协议
下载PDF
High-level distributed coordination via distributed Haskell 被引量:1
14
作者 ZHANG Ying-zhou ZHANG Wei-feng +1 位作者 ZHOU Guo-qzang QIAN Jun-yan 《通讯和计算机(中英文版)》 2007年第5期1-7,共7页
关键词 分布式调和 函数语言 面向对象分布式语言 格拉斯哥分布式 Haskell编程
下载PDF
Direction-dependent functions of physical properties for crystals and polycrystals
15
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
下载PDF
不同空间取向角椭球颗粒电磁散射特性的Rayleigh解
16
作者 王娟 李兴财 程宁 《兰州大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第6期711-717,共7页
建立用Rayleigh近似求解不同空间取向角椭球颗粒电磁散射性质的新方法.结果表明,空间取向角对椭球颗粒的电磁散射特性有非常重要的影响.与等体积球体相比,在颗粒取向角的极角分量处于部分角度时椭球颗粒的散射效率、吸收效率增加25%;在... 建立用Rayleigh近似求解不同空间取向角椭球颗粒电磁散射性质的新方法.结果表明,空间取向角对椭球颗粒的电磁散射特性有非常重要的影响.与等体积球体相比,在颗粒取向角的极角分量处于部分角度时椭球颗粒的散射效率、吸收效率增加25%;在某些情况下散射效率、吸收效率显著减小,特别在极角为90°时减小20%.随着轴比的增加,旋转椭球体与其等体积球体的散射效率和吸收效率的比值呈指数减小趋势,但部分极角下呈线性增加趋势.通过对比颗粒取向角呈均匀分布与正态分布时椭球颗粒系统的吸收系数变化,揭示颗粒取向角分布函数在相关计算中的意义. 展开更多
关键词 椭球粒子 等效介电张量 Rayleigh散射 取向角分布函数
下载PDF
不同取向条件下Al-Cu-Mg-Sc-Zr合金薄板的组织与性能 被引量:6
17
作者 郭加林 尹志民 +2 位作者 唐蓓 商宝川 何振波 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2011年第7期1923-1927,共5页
采用室温拉伸性能测试、金相组织观察、透射电子显微分析以及取向分布函数(ODF)测定研究T3态Al-Cu-Mg-Sc-Zr合金(2524SZ-T3)薄板在不同取向条件下的显微组织和力学性能。研究结果表明:合金薄板在与轧制方向呈30°,60°和90°... 采用室温拉伸性能测试、金相组织观察、透射电子显微分析以及取向分布函数(ODF)测定研究T3态Al-Cu-Mg-Sc-Zr合金(2524SZ-T3)薄板在不同取向条件下的显微组织和力学性能。研究结果表明:合金薄板在与轧制方向呈30°,60°和90°方向上的强度较0°和45°方向上的强度稍低,伸长率则在60°方向上最高,薄板的抗拉强度、屈服强度和伸长率平面各向异性指数分别为0.9%,3.3%和6.6%;2524SZ-T3态铝合金薄板具有明显的再结晶织构{110}-111-和CubeND旋转立方织构{001}-310-,同时还保留较弱的轧制织构即Goss织构{011}-100-;不同取向条件下2524SZ-T3合金薄板的平面各向异性与合金的晶粒结构以及晶体学织构密切相关。 展开更多
关键词 AL-CU-MG合金 平面各向异性 取向分布函数(odf) 晶体学织构
下载PDF
板材冲压成形的晶体塑性有限元模拟 被引量:8
18
作者 李大永 张少睿 +2 位作者 彭颖红 刘守荣 仇素萍 《机械工程学报》 EI CAS CSCD 北大核心 2008年第1期190-194,共5页
将率相关晶体塑性本构理论引入Mindlin曲壳单元模型与动力显式有限元法,采用切线系数法计算剪切应变率,根据晶体取向正态分布规律在单元积分点处分配晶体取向,按各晶体取向体积分数的加权平均计算多晶体应力,开发晶体塑性动力显式有限... 将率相关晶体塑性本构理论引入Mindlin曲壳单元模型与动力显式有限元法,采用切线系数法计算剪切应变率,根据晶体取向正态分布规律在单元积分点处分配晶体取向,按各晶体取向体积分数的加权平均计算多晶体应力,开发晶体塑性动力显式有限元程序,实现板材冲压成形过程模拟和晶体取向演化预示。以主要初始织构为铜织构和S织构的轧制铝板为对象,对方盒件冲压成形过程及织构演化进行数值模拟,计算结果与试验结果呈现出较好的一致性。通过晶体弹塑性有限元法不仅可以预示板材宏观成形构形变化,而且能够预测板材织构的演化情况。模拟结果显示在方盒件冲压成形过程中,铜织构和S织构为不稳定取向,变形后逐渐转到其他取向。 展开更多
关键词 晶体塑性模型 织构 Mindlin壳单元 动力显式有限元 取向分布函数
下载PDF
拉拔单晶铜线材形变织构的研究 被引量:6
19
作者 李巍 严文 +1 位作者 陈建 范新会 《兵器材料科学与工程》 CAS CSCD 北大核心 2008年第1期1-5,共5页
采用水平单晶连铸方法制备直径为8mm的单晶铜线材,经拉拔得到直径为7、5、3、1mm的形变铜线材,应用取向分布函数分别对不同形变量单晶铜线材沿线材半径方向的织构组分进行了研究。结果表明:单晶铜在形变过程中,各层主要存在<100>... 采用水平单晶连铸方法制备直径为8mm的单晶铜线材,经拉拔得到直径为7、5、3、1mm的形变铜线材,应用取向分布函数分别对不同形变量单晶铜线材沿线材半径方向的织构组分进行了研究。结果表明:单晶铜在形变过程中,各层主要存在<100>纤维织构组分,取向主要向{100}<001>、{110}<001>聚集;形变单晶铜线材各层织构组分存在一定的差异,主要是由于单晶铜线材在拉拔过程中变形的不均匀性所致;剪切变形是织构组分转变的主要原因。 展开更多
关键词 单晶铜线材 织构 取向分布函数
下载PDF
晶粒度对立方系材料织构及残余应力分析的影响 被引量:3
20
作者 于利根 徐可为 +1 位作者 何家文 顾海澄 《金属学报》 SCIE EI CAS CSCD 北大核心 1995年第5期B233-B237,共5页
本文推导了立方系伪各向同性多晶体由织构取向因子分析的分辨力所决定的临界晶粒度及对残余应力测试产生影响的临界晶粒度,说明了伪各向同性多晶体在织构分析无法分辨的晶粒度区域,仍可能产生残余应力测试曲线的非线性现象,并以钢铁... 本文推导了立方系伪各向同性多晶体由织构取向因子分析的分辨力所决定的临界晶粒度及对残余应力测试产生影响的临界晶粒度,说明了伪各向同性多晶体在织构分析无法分辨的晶粒度区域,仍可能产生残余应力测试曲线的非线性现象,并以钢铁材料的应力测试为例,说明在一定的晶粒度下,d-sin2Ψ关系出现非线性时,必须同时考虑晶粒度及织构对X射线应力测定曲线振荡现象的贡献。 展开更多
关键词 金属材料 晶粒度 残余应力
下载PDF
上一页 1 2 7 下一页 到第
使用帮助 返回顶部