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91.
As Chinese cities rapidly transformed themselves into consumerist societies, the relationship between consumers and consumption
space under stratification has become a new research area in the field of urban social geography. Based on a consumer behavior
analysis, this study explores the relationship between consumption space and the social strata of consumers in typical shopping
malls in Guangzhou where the first shopping mall in China was built. The result shows that shopping malls have performed significant
constructive functions of organizing consumers from different social classes into different consumption space. For middle-
and upper-class consumers, the function of shopping malls centers on utilitarian consumption, identity recognition, and identity
construction; whereas for lower-class consumers, its function revolves around pleasure and enjoyment. The symbolism of consumption
space is the underlying reason for shopping malls to have their social constructive function. The findings of this research
suggest that: 1) a shopping mall is a productive consumption space and a geographical space with subjectivity; 2) the micro-location
of a shopping mall has social construction function; and 3) symbolic consumption is the core of social construction. 相似文献
92.
有限元与改进单纯形法联合编程技术在位移反分析中的应用 总被引:1,自引:0,他引:1
根据弹性地基梁法基本思想,考虑基坑分步开挖和逐级加撑的动态施工因素,通过有限元计算模拟基坑实际开挖过程。结合现场监测数据,采用位移反分析方法反演各土层m 值,并准确预测后续工况支护体的变形。采用有限元通用软件ANSYS内嵌的APDL语言编程建立支护体有限元计算模型,并应用数学软件MATLAB编制“改进单纯形法”优化程序,编写了接口程序,实现了MATLAB对ANSYS模型的实时循环调用和逐步寻优。武汉长江隧道武昌明挖段基坑工程算例证明,基于单纯形法的联合编程技术能方便、高效地被应用于支护体位移反分析预测中。建立了基于本工况预测下一工况或相邻断面的扩展型位移反分析预测模型,预测结果与实测结果拟合程度较高。 相似文献
93.
94.
《The Professional geographer》2013,65(3):324-329
Two traditional Jewish approaches to the location of synagogues can be found, one symbolic and one functional. The locational requirements are not identical; the symbolic approach deals with idealistic spatial status while the functional approach poses realistic locational demands. This spatio-locational conflict reflects a problematic situation on both theoretical and practical levels. 相似文献
95.
Ramesh S.V. Teegavarapu 《水文科学杂志》2013,58(3):383-406
Abstract New mathematical programming models are proposed, developed and evaluated in this study for estimating missing precipitation data. These models use nonlinear and mixed integer nonlinear mathematical programming (MINLP) formulations with binary variables. They overcome the limitations associated with spatial interpolation methods relevant to the arbitrary selection of weighting parameters, the number of control points within a neighbourhood, and the size of the neighbourhood itself. The formulations are solved using genetic algorithms. Daily precipitation data obtained from 15 rain gauging stations in a temperate climatic region are used to test and derive conclusions about the efficacy of these methods. The developed methods are compared with some naïve approaches, multiple linear regression, nonlinear least-square optimization, kriging, and global and local trend surface and thin-plate spline models. The results suggest that the proposed new mathematical programming formulations are superior to those obtained from all the other spatial interpolation methods tested in this study. Editor D. Koutsoyiannis; Associate editor S. Grimaldi Citation Teegavarapu, R.S.V., 2012. Spatial interpolation using nonlinear mathematical programming models for estimation of missing precipitation records. Hydrological Sciences Journal, 57 (3), 383–406. 相似文献
96.
AbstractThe quantification of the sediment carrying capacity of a river is a difficult task that has received much attention. For sand-bed rivers especially, several sediment transport functions have appeared in the literature based on various concepts and approaches; however, since they present a significant discrepancy in their results, none of them has become universally accepted. This paper employs three machine learning techniques, namely artificial neural networks, symbolic regression based on genetic programming and an adaptive-network-based fuzzy inference system, for the derivation of sediment transport formulae for sand-bed rivers from field and laboratory flume data. For the determination of the input parameters, some of the most prominent fundamental approaches that govern the phenomenon, such as shear stress, stream power and unit stream power, are utilized and a comparison of their efficacy is provided. The results obtained from the machine learning techniques are superior to those of the commonly-used sediment transport formulae and it is shown that each of the input combinations tested has its own merit, as they produce similarly good results with respect to the data-driven technique employed.
Editor Z.W. Kundzewicz 相似文献
97.
在分析数据存储文件格式的基础上,设计了数据的读取算法,对观测数据进行自动化识别,生成标准记录格式的观测数据文件和CASS通用编码格式的展点数据文件,从而减轻了内业数据处理工作量,提高了工作效率。 相似文献
98.
李曦凌 《测绘与空间地理信息》2013,(9)
基于Casio fx-9860 G SD型计算器的特性,笔者利用VS2008开发出能够读取、处理维地道路系统生成的Excel直曲表,并能生成计算器能读取的线元串列数据库文件的软件。然后利用生成的串列文件在计算器中进行线路任意里程正反算。实现了公路平面设计参数的自动转换、输入。本文着重介绍软件开发、工程实例中遇到的问题和解决方法。通过多个工程实践证明,该系统可以很好地帮助测量技术人员快速、准确地进行横断面测量、线路中边桩放样、线路地形图等工作,提高了线路测量的效率和规范性。 相似文献
99.
Optimization of land use structure consists of economic and social and ecological optimization. Applying the minds of system engineering and principles of ecology, this paper presents such thoughts: the optimal forest-coverage rate calculated according to the reality of a district is set as main standard of ecological rationality in the district; through considering the value of ecosystem services of the land with GREEN equivalent (mainly cultivated land and grassland) and based on the rule, GREEN equivalent, this paper introduces the area conversion between woodland and cultivated land, also between woodland and grassland; this paper establishes a multi-dimension controlling model of optimization of land use structure. In addition, a multi-objective linear programming model for optimization of land use structure is designed. In the end, this paper tests and verifies this theory of ecological optimization, taking Qionghai city in Hainan Province as an example. 相似文献
100.