基于GIS和分形理论的山西屯留县土地利用空间格局变化

该文以分形理论为基础，在地理信息系统技术支持下，对山西省屯留县土地利用空间格局变化进行了研究。通过对山西省屯留县土地利用数据库中空间数据的提取，运用面积－周长分形模型，分别计算出了1990年和2001年各种土地利用类型的分维数和稳定性指数。该文还引入了景观生态学中的相关指数—斑块密度指数，景观斑块数破碎化指数，斑块形状破碎化指数及景观多样性指数，并进行了定量分析，进一步揭示了屯留县土地利用空间格局变化，以期为开展区域土地整理、促进土地合理利用以及保持区域景观格局的持续发展提供参考。     

Effect of Disturbance on the Cylindrical Cavity Expansion in Saturated Soft Clay

According to the fact that the undrained shear strength decreases in the field vane test,applying the cylindrical expansion theory and assuming that the saturated soft clay satisfies Tresca yield criterion,the disturbance degree function D is given on the basis of the sensibility of saturated soft clay.Considering that the undrained shear strength is the linear function of the disturbance degree D in plastic region,the elastic-plastic solution of the cylindrical expansion has been gained.     

Elastic-plastic Solution of Expansion of Spherical Cavities under 3D Loading

In elastic-plastic solution of expansion of spherical cavities, based on Mohr-Coulomb strength criterion, the effect of intermediate principal stress on yield and failure of soil is not analyzed. Therefore, there is disparity between results obtained by Mohr-Coulomb strength criterion and those obtained from experimental data. In this paper, the elastic-plastic solution of expansion of spherical cavities, based on unified strength theory is established and unified solutions are obtained. The corresponding solutions of different materials can be obtained. The unified solution cannot only be used to fit the properties of the materials with different tension-pressure strength, but also those with equal tension-pressure strength. The results show that by this solution, full use of the properties of the materials can be attained to reduce supports, which is of important significance for engineering     

Knowledges of the creative economy: Towards a relational geography of diffusion and adaptation in Asia

Abstract: Recent dialogues in geography and the social sciences have reminded researchers of the extent to which academic and policy knowledges are socially and spatially embedded – that is, they circulate through formal and informal systems of publishing, exchange, commodification and cultural influence. Academic and policy knowledges are, in short, very much a part of the creative economy. In light of this, our paper surveys knowledges of the creative economy itself, as reflected in a geography of industry reports and government policy statements in selected Asian countries. Using a post‐positivist framework adapted from diffusion theory, we critically interpret the circulation, mutation and adaptation of knowledges of the creative economy, claims to its significance, areas of emphases and notable silences.     

地震时城市供水管网连通可靠性分析

在分析地震条件下管线功能函数及极限状态方程基础上,对城市供水管单元体进行震害预测。以供水管网系统作为边权的有向网络图,通过基于神经网络的Monte Carlo方法,模拟各管线运行状态及其破坏状态。结合图论理论,分析供水管网的管线连通可靠性。     

基于土壤学理论的土地整理研究

从耕地质量评价、"补充耕地的数量、质量实行按等级折算"、土壤形成和演变、土地的养育和涵养功能源于土壤以及实施土壤保护、培肥与改良工程等方面,阐述了土壤学作为土地整理最重要的支撑理论,指出了土壤学在土地整理过程中的应用首先是土壤保护,维护土壤肥力和自动协调功能,实现土地生产力在利用中提高和土地可持续利用;其次是改土培肥,即根除土壤障碍因子,改善土宜条件等,提高土地生产力.在上述研究的基础上,提出了基于土壤学理论的土地整理实践活动,即因区护土和因地改土培肥等.     

图论法查找和解算工艺尺寸链的研究

介绍了图论法查找和解算工艺尺寸链的原理和方法。用此法解决复杂的工艺尺寸链问题,不仅简捷,而且能及时发现在采用的工艺中图纸中的错误。     

复合材料层合板高阶剪切变形理论位移模式的研究

在总结现有复合材料层合板高阶理论的基础上，推导出一种基于整体-局部位移假设的1，2-3高阶剪切变形理论，使其既满足层间位移、应力连续条件，也满足上、下自由表面条件。比较了应用该高阶理论的位移有限单元数值的计算结果。证明了此高阶理论既能很好地描述剪切变形效应，又能较好地计算整体位移参数和横向剪切应力。