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41.
Analysis of monthly mean river temperatures, recorded on an hourly basis in the middle reaches of the Loire since 1976, allows reconstruction by multiple linear regression of the annual, spring and summer water temperatures from equivalent information on air temperatures and river discharge. Since 1881, the average annual and summer temperatures of the Loire have risen by approximately 0.8?°C, this increase accelerating since the late 1980s due to the rise in air temperature and also to lower discharge rates. In addition, the thermal regime in the Orleans to Blois reach is considerably affected by the inflow of groundwater from the Calcaires de Beauce aquifer, as shown by the summer energy balance. To cite this article: F. Moatar, J. Gailhard, C. R. Geoscience 338 (2006).  相似文献   
42.
张维正 《探矿工程》2006,33(6):1-3,7
以沈阳市某深基坑支护及降水工程在密集建筑群中施工为例,介绍了该支护工程的设计与施工,阐述了该工程变形监测方法并对其结果进行了分析,总结了在沈阳地区密集建筑群中进行基坑开挖的设计与施工经验。  相似文献   
43.
根据拟建建筑基坑的工程地质条件、周边环境条件、基坑开挖深度等特点综合考虑,对基坑分段采用超前微型桩支护加土钉墙、放坡加土钉墙2种复合支护方案。实践证明,该工程所采用的多种复合式支护实施方案,技术安全可靠,经济合理。  相似文献   
44.
主要介绍了广州科学城保利林语山庄高边坡支护设计方案与施工方法。支护方案综合采用了锚索、锚杆、抗滑桩、钢管桩、格构梁及挡土墙等多种支护方法,有效地提高了边坡的稳定性。应用有限元方法来验证设计方案的合理性,模拟结果与工程实践基本吻合。  相似文献   
45.
A decision support system (DSS) has been developed to assist expert and non-expert users in the evaluation and selection of eco-engineering strategies for slope protection. This DSS combines a qualitative hazard assessment of erosion and mass movements with a detailed catalogue of eco-engineering strategies for slope protection of which the suitability is evaluated in relation to the data entered. The slope decision support system (SDSS) is a knowledge based DSS in which knowledge is stored in frames containing rules that can evaluate the available information for a project, stored as project specific information (PSI) in a data file. The advantages of such a system are that it accepts incomplete information and that the qualitative nature of the information does not instil the user with a sense of unjustified exactitude. By its multidisciplinary and progressive nature, the DSS will be of value during the initial stages of an eco-engineering project when data collection and the potential of different eco-engineering strategies are considered. The accent of the output of the DSS is on the application of eco-engineering strategies for slope protection as an environmentally-friendly solution aiding sustainable development. For its acceptance within the engineering community, the DSS needs to prove its predictive capacity. Therefore, its performance has been benchmarked against successful and unsuccessful cases of slope stabilisation using eco-engineering. The target audience and the areas of application of this DSS are reviewed and the strategies for further development in this area suggested.  相似文献   
46.
Governmental authorities are forced by law to make decisions within the framework of European, national and regional directives in the fields of spatial planning, groundwater and environmental protection. These tasks can be supported by a decision-support system, which integrates data from various sources and helps to make decision processes more effective and transparent. Basic work for such a decision support system has been done in a transnational and interdisciplinary project (Interreg II C: KATER), including metadata definition, metadata system, cartographic tools and GIS tools. The direct integration of these tools and information in the decision process will be implemented in the next few years (project KATER II).  相似文献   
47.
VML在WebGIS图形显示中的应用研究   总被引:3,自引:0,他引:3  
针对目前被动式WebGIS地图显示的局限,提出了引入VML的解决办法,使客户端容易实现矢量地图显示、地物动态变化显示、专题制图显示等,丰富了WebGIS的地图表现方式。  相似文献   
48.
基于3DCM的日照分析模型研究   总被引:3,自引:0,他引:3  
讨论了几何3DCM(three dimension city model)日照分析的基本模型.基于3DCM日照分析的3个难点问题——阴影显示、日照时间计算、日照间距计算.实现了日照分析的算法功能,并给出了实验与模拟分析结果。  相似文献   
49.
航空影像分割的最小二乘支持向量机方法   总被引:5,自引:0,他引:5  
将最小支持向量机LS-SVM用于航空影像的分割,讨论了不同核函数对分割结果的影响和稀疏化处理对决策函数的影响。试验表明了LS-SVM方法用于航空影像分割的可行性。  相似文献   
50.
Present methodological research on geographically weighted regression (GWR) focuses primarily on extensions of the basic GWR model, while ignoring well-established diagnostics tests commonly used in standard global regression analysis. This paper investigates multicollinearity issues surrounding the local GWR coefficients at a single location and the overall correlation between GWR coefficients associated with two different exogenous variables. Results indicate that the local regression coefficients are potentially collinear even if the underlying exogenous variables in the data generating process are uncorrelated. Based on these findings, applied GWR research should practice caution in substantively interpreting the spatial patterns of local GWR coefficients. An empirical disease-mapping example is used to motivate the GWR multicollinearity problem. Controlled experiments are performed to systematically explore coefficient dependency issues in GWR. These experiments specify global models that use eigenvectors from a spatial link matrix as exogenous variables.This study was supported by grant number 1 R1 CA95982-01, Geographic-Based Research in Cancer Control and Epidermiology, from the National Cancer Institute. The author thank the anonymous reviewers and the editor for their helpful comments.  相似文献   
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