期刊文献+
共找到7篇文章
< 1 >
每页显示 20 50 100
基于耗散结构论的区域集装箱港口群体系结构演化模型研究
1
作者 赵春芳 匡桂华 《物流工程与管理》 2016年第10期8-10,16,共4页
港口对城市和区域经济的发展起着巨大的促进作用,而区域经济的发展是港口发展的强有力后盾,两者相互影响相互增强。随着经济发展环境改变、物流技术进步和港口经营模式转变等因素影响,区域港口群系统各港口通过竞争与合作、自我组织形... 港口对城市和区域经济的发展起着巨大的促进作用,而区域经济的发展是港口发展的强有力后盾,两者相互影响相互增强。随着经济发展环境改变、物流技术进步和港口经营模式转变等因素影响,区域港口群系统各港口通过竞争与合作、自我组织形成港口体系结构从分散到集中到整合的发展阶段。文中采用耗散结构理论构建区域集装箱港口群体系结构模型,对促进港口体系结构的合理布局以及有效竞争,优化资源配置和促进港口发展具有重要意义。 展开更多
关键词 耗散结构 区域集装箱港口群 体系结构演化模型
下载PDF
带特定选择机制的供应系统网络模型构建及分析 被引量:3
2
作者 于灏 马妍 +2 位作者 王新华 饶卫振 白丽 《系统工程学报》 CSCD 北大核心 2017年第5期686-698,共13页
针对主观偏好影响在供应系统演化过程中的重要作用,提出了带有主观偏好"特定选择"机制的供应网络结构演化模型.研究了一般供应网络的结构特征与形成机制.构建了主观偏好选择表达式.设计了偏好选择的主客观影响权重系数,使得... 针对主观偏好影响在供应系统演化过程中的重要作用,提出了带有主观偏好"特定选择"机制的供应网络结构演化模型.研究了一般供应网络的结构特征与形成机制.构建了主观偏好选择表达式.设计了偏好选择的主客观影响权重系数,使得模型中主观偏好影响权重可调.通过模拟研究,分析了模型参数与网络结构的关系.研究结果验证了模型网络与现实供应系统基本结构特征的一致性,表明了所建模型能够较好地反映供应系统的基本结构特征,能够为基于系统结构的供应系统动力学行为研究,尤其是考虑主观决策偏好的供应系统行为研究提供支持. 展开更多
关键词 供应系统 供应链网络 特定选择 结构演化模型 主观偏好
下载PDF
桑植—石门复向斜的形成与演化 被引量:2
3
作者 张旭亮 何登发 《地质科学》 CAS CSCD 北大核心 2018年第1期269-288,共20页
桑植-石门构造带是湘鄂西构造带最东边的一个二级构造单元,紧密接壤雪峰陆内变形系统的北西侧,属于二者之间的盆地过渡带,同时也是一个典型的多旋回叠合的复合沉积区。该地区自前寒武纪以来长期受板块构造运动和陆内造山运动的影响... 桑植-石门构造带是湘鄂西构造带最东边的一个二级构造单元,紧密接壤雪峰陆内变形系统的北西侧,属于二者之间的盆地过渡带,同时也是一个典型的多旋回叠合的复合沉积区。该地区自前寒武纪以来长期受板块构造运动和陆内造山运动的影响,构造轴迹由NNE-SSW向逐渐过渡到近E-W向,构造变形极其复杂。对该构造带进行精细的构造解析有助于揭示雪峰山和川东-湘鄂西构造带之间的过渡关系以及探究中上扬子陆内构造的变形机制,对复杂地形区的油气勘探具有重要的指导意义。在此之前,受限于地震资料的品质和数量,前人对湘鄂西-雪峰山之间过渡带的构造变形特征,构造演化及其动力机制的认识还不完善,尚需进一步深化。本文以最新的二维地震资料为基础,结合浅表地质资料和测井资料,依据断层相关褶皱原理,精细刻画了桑植-石门构造带的构造特征,建立了构造带内南、北段相应的地质结构演化模型:桑植-石门构造带南、北段的变形过程大体相似,都是在反冲断层与低角度逆冲推覆断层共同作用下构成了原地埋藏体,之后受燕山期以来的多幕构造运动影响,逐步形成现今的褶皱形态。但二者之间也存在着一定的差异。导致其差异的主控因素:1)“钉线”与变形带之间的距离;2)后缘的雪峰推覆体的差异变形。 展开更多
关键词 桑植—石门构造带 构造几何学与运动学 地质结构演化模型 变形因素
下载PDF
EVOLUTIONARY MODEL OF FREE ECONOMIC ZONES——Different Generations and Structural Features 被引量:10
4
作者 MENGGuang-wen 《Chinese Geographical Science》 SCIE CSCD 2005年第2期103-112,共10页
Free economic zone (FEZ) has a long history and plays a more and more important role in the world economy. Most studies, however, focused on the theoretical analysis of benefit and cost as well as the economic role of... Free economic zone (FEZ) has a long history and plays a more and more important role in the world economy. Most studies, however, focused on the theoretical analysis of benefit and cost as well as the economic role of FEZ in the less developed countries and little attention has been paid to the evolution of FEZ. This paper will improve the above-mentioned studies and put forward the structural and spatial evolutionary model of FEZ by analyzing the development of objectives, preferential policy, governance structure, industrial sectors and location of FEZs based on the international economic and political development. FEZs develop towards: 1) more comprehensive and macro objectives, 2) more industry-oriented and multi-preferential policies, 3) more cross-national and combination zones with administrative areas, 4) more technology-intensive and multi-industries, 5) more flexible location and larger spatial dimensions, 6) more rapid evolution and typologies, and 7) more economic integration to the host economy. 展开更多
关键词 free economic zone structural evolutionary model spatial evolution
下载PDF
Some Evolution Hierarchies Derived from Self-dual Yang-Mills Equations 被引量:8
5
作者 张玉峰 韩耀宗 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第11期856-872,共17页
We develop in this paper a new method to construct two explicit Lie algebras E and F. By using a loop algebra E of the Lie algebra E and the reduced self-dual Yang-Mills equations, we obtain an expanding integrable mo... We develop in this paper a new method to construct two explicit Lie algebras E and F. By using a loop algebra E of the Lie algebra E and the reduced self-dual Yang-Mills equations, we obtain an expanding integrable model of the Giachetti-Johnson (G J) hierarchy whose Hamiltonian structure can also be derived by using the trace identity. This provides a much simplier construction method in comparing with the tedious variational identity approach. Furthermore, the nonlinear integrable coupling of the GJ hierarchy is readily obtained by introducing the Lie algebra gN. As an application, we apply the loop algebra E of the Lie algebra E to obtain a kind of expanding integrable model of the Kaup-Newell (KN) hierarchy which, consisting of two arbitrary parameters a and β, can be reduced to two nonlinear evolution equations. In addition, we use a loop algebra F of the Lie algebra F to obtain an expanding integrable model of the BT hierarchy whose Hamiltonian structure is the same as using the trace identity. Finally, we deduce five integrable systems in R3 based on the self-dual Yang-Mills equations, which include Poisson structures, irregular lines, and the reduced equations. 展开更多
关键词 Lie algebra Hamiltonian structure Yang-Mills equation
下载PDF
The Redesign of the Business Model Based on the Structural Perspective
6
作者 Ding Ning Song Yingge Zhang Yijin 《Chinese Business Review》 2013年第6期407-413,共7页
At present, whether internally or abroad, whether in the theory or business, there is a lack of a unified understanding about the basic concepts of structural system and theoretical category of enterprise business mod... At present, whether internally or abroad, whether in the theory or business, there is a lack of a unified understanding about the basic concepts of structural system and theoretical category of enterprise business model, and its theoretical analysis framework has not been built up, it is the exploratory phase of the model research in the mass. This study aims to analyze the formation mechanism, action mechanism, and evolution mechanism about the business model from the perspective of structure, and designs the enterprise business model architecture and forms a system, besides, explores approaches and strategies about enterprise carrying out business model innovation, and does beneficial bedding in order to use and improve the theoretical system in the process of the enterprise management practice. The significance of this study is to provide analytical methods and tools for the business model questions in the enterprise management practice. This paper firstly defined the connotation of enterprise business model and summarized the seven characteristics of the corporate business model. On the basis of outlining the enterprise business model design theory, the structural design of the corporate business model is mainly discussed. This paper designed the structure of the business model on modular perspective, proposed four constituent units and nine elements of enterprise business model structure system. Through the design of the enterprise business model structure and analysis of the elements that constitute structure, provide the basis for the transformation of innovative enterprise business model, or both enterprise business models, avoid the lack of elements of the enterprise business model structure and lead to business failure. Finally, the paper concludes with the five core strategies for the implementation of the enterprise business model design. 展开更多
关键词 analysis of methods enterprise business model STRUCTURE REDESIGN
下载PDF
An unconventional phase field modeling of domains formation and evolution in tetragonal ferroelectrics 被引量:3
7
作者 ZHOU YouGang PENG JinLin +1 位作者 PAN Kai LIU YunYa 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第7期1059-1064,共6页
Based on characteristic functions of variants, we developed an unconventional phase field modeling for investigating domains formation and evolution in tetragonal ferroelectrics. In order to develop this computational... Based on characteristic functions of variants, we developed an unconventional phase field modeling for investigating domains formation and evolution in tetragonal ferroelectrics. In order to develop this computational approach, we constructed the anisotropy energy of tetragonal variants, which is used instead of Landau-Devonshire potential in the conventional phase field method, resulting in that much fewer parameters are needed for simulations. This approach is advantageous in simulations of emerging ferroelectric materials. We employ it to study the formation and evolution of domains in tetragonal barium titanate single crystal, as well as the nonlinear behaviors under cyclical stress and electric field loading. A multi-rank laminated ferroelectric domain pattern, 90° domain switching accompanied by polarization rotation, and 180° domain switching accompanied by move of domain wall are predicted. It is found that the speed of 90° domain switching is slower than that of 180° domain switching, due to both polarization and transformation strain changed in 90° domain switching. It also suggests that large strain actuation can be generated in single crystal ferroelectrics via combined electromechanical loading inducing 90° domain switching. The good agreement between simulation results and experimental measurements is observed. 展开更多
关键词 phase field simulation ferroelectric domains formation and evolution ferroelectric materials
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部