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In a piled raft, the length and arrangement of piles has a significant effect on the stresses and deflections of the raft. The use of piles with different dimensions and properties below a raft is an innovative concept and can optimize the design of a piled raft. In this study, an integral equation method with a fictitious pile model was adopted to analyze the piled raft foundation with dissimilar piles. The Fredholm integral equations of the second kind were obtained for this problem. The loads shared by piles and subsoil, the load transfer, and the settlement of the piled raft were obtained using numerical calculation. The results from the present method were compared with those in the literature. An optimization technique was introduced to design piled rafts with dissimilar piles. The stiffening effect of piles on the surrounding soil is also discussed as compared the conventional interaction factor approach. 相似文献
125.
The chamber geometry is one of the key factors that influences the performance of a cone crusher. The design of the chamber geometry should take product quality and crushing efficiency into account. In this paper the kinematics of rock material in a crushing chamber, as interparticle breakage occurs, has been analyzed and the chamber division is achieved. Based on the chamber division and a population balance model, the method for chamber geometry design is presented. Combining the empirical model for predicting particle shape with the size distribution model, a flakiness prediction model is proposed. With the size reduction model and flakiness prediction model as constraints, an optimization of the crushing chamber is achieved. Finally, the validity of the crushing chamber optimization model has been verified by an appropriate prototype test. 相似文献
126.
Due to the multiplicity of factors including weather, the underlying surface and human activities, the complexity of parameter
optimization for a distributed hydrological model of a watershed land surface goes far beyond the capability of traditional
optimization methods. The genetic algorithm is a new attempt to find a solution to this problem. A genetic algorithm design
on the Distributed-Hydrology-Soil-Vegetation model (DHSVM) parameter optimization is illustrated in this paper by defining
the encoding method, designing the fitness value function, devising the genetic operators, selecting the arithmetic parameters
and identifying the arithmetic termination conditions. Finally, a case study of the optimization method is implemented on
the Lushi Watershed of the Yellow River Basin and achieves satisfactory results of parameter estimation. The result shows
that the genetic algorithm is feasible in optimizing parameters of the DHSVM model. 相似文献
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基于Servlet的企业级地理信息网络发布的开发与实现 总被引:2,自引:0,他引:2
地理信息由于其在信息世界中的基础地位,迫切要求实现在Web上发布。Servlet是一种在服务器端开发Web应用的Java技术。通过实例,简要分析了Servlet技术特点及其在构建WebGIS上的优势,并结合MapXtremeJava,以Jbuilder为集成开发工具开发了企业级地理信息发布实例———移动通信网络优化系统。重点阐述了系统设计及实现方法。实践表明,本系统具有开放性、安全性等特点,提供了分布式计算平台架构,可实现对移动通信网络资源的可视化管理。Servlet技术用于构建WebGIS不仅可行,而且大大提高并行访问的速度。 相似文献
129.
PrabhataK.SWAMEE NimishaSWAMEE 《国际泥沙研究》2004,19(4):312-318
Design equations for minimum area or maximum velocity canal-sections for transport of bulk sediment carried by water have been obtained. Such canals are economically feasible in the terrain where large slopes are available. The design procedure is illustrated by a practical example. 相似文献
130.
Arsalan Ghorbanian Mahmod Reza Sahebi Ali Mohammadzadeh 《Comptes Rendus Geoscience》2019,351(4):332-339
This study suggests a novel approach to the retrieval of soil surface parameters using a single-acquisition single-configuration synthetic-aperture radar (SAR) system. Soil surface parameters such as soil moisture and surface roughness are key elements for many environmental studies, including Earth surface water cycles, energy exchange, agriculture, and geology. Remote sensing techniques, especially SAR data, are commonly used to retrieve such soil surface parameters over large areas. Several backscattering models have been proposed for soil surface parameters retrieval from SAR data. However, commonly, these backscattering models require multi configuration SAR data, including multi-polarization, multi-frequency, and multi-incidence angle. Here we propose a methodology that employs single-acquisition single-configuration SAR data for the retrieval of soil surface parameters. The originality is to use single-acquisition single-configuration SAR data to retrieve the soil surface parameters using an optimization approach by the genetic algorithm (GA); we have used the modified Dubois model (MDM) in HH polarization as the backscattering model. Three HH polarization and C band data sets from Quebec (Radarsat-1), Ontario (SIR-C), and Oklahoma (AIRSAR) were analyzed. The retrieved values of soil moisture and soil surface roughness were then compared to ground truth measurements with corresponding parameters. We employed diverse criteria, including the mean absolute error (MAE), the root mean square error (RMSE), the coefficient of performance (CP), and the correlation coefficient to investigate the performance of the proposed methodology. This analysis suggests the capability of the GA for the retrieval of soil surface parameters. Based on our findings, this method presents a viable alternative approach to the retrieval of soil surface parameters when only single-acquisition single-configuration SAR data is available. 相似文献