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1.
T. G. Sitharam Pijush Samui P. Anbazhagan 《Geotechnical and Geological Engineering》2008,26(5):503-517
Geospatial technology is increasing in demand for many applications in geosciences. Spatial variability of the bed/hard rock
is vital for many applications in geotechnical and earthquake engineering problems such as design of deep foundations, site
amplification, ground response studies, liquefaction, microzonation etc. In this paper, reduced level of rock at Bangalore,
India is arrived from the 652 boreholes data in the area covering 220 km2. In the context of prediction of reduced level of rock in the subsurface of Bangalore and to study the spatial variability
of the rock depth, Geostatistical model based on Ordinary Kriging technique, Artificial Neural Network (ANN) and Support Vector
Machine (SVM) models have been developed. In Ordinary Kriging, the knowledge of the semi-variogram of the reduced level of
rock from 652 points in Bangalore is used to predict the reduced level of rock at any point in the subsurface of the Bangalore,
where field measurements are not available. A new type of cross-validation analysis developed proves the robustness of the
Ordinary Kriging model. ANN model based on multi layer perceptrons (MLPs) that are trained with Levenberg–Marquardt backpropagation
algorithm has been adopted to train the model with 90% of the data available. The SVM is a novel type of learning machine
based on statistical learning theory, uses regression technique by introducing loss function has been used to predict the
reduced level of rock from a large set of data. In this study, a comparative study of three numerical models to predict reduced
level of rock has been presented and discussed. 相似文献
2.
3.
基于退火BP神经网络的GPS高程转换 总被引:1,自引:0,他引:1
阐述模拟退火算法的基本思想和原理,提出并介绍模拟退火算法优化的BP神经网络模型在GPS高程转换中的具体应用,同时编写相应的MATLAB处理程序,结合大量数据进行仿真实验,结果表明文中提出的退火BP神经网络模型具有收敛速度快、精度高、避免陷入局部最小的优良特性。 相似文献
4.
浅谈建筑设计企业的数据中心建设 总被引:1,自引:0,他引:1
信息系统数据和计算能力逐步集中的发展趋势以及信息系统逐步成为企业核心业务的支撑,使得企业数据中心的作用越来越重要。如何搞好数据中心建设,保障数据系统的安全、稳定运行,成为信息主管首先要考虑的问题。首先讨论数据中心的作用和数据中心与信息系统之间的关系,然后介绍一个目前在国际上处于领先水平、防护等级最高的数据中心的实例,最后论述数据中心的实施对策。 相似文献
6.
互联网在方便人们交流、共享信息的同时,也带来了极大的安全问题.信息隐藏是解决信息安全的一种有效手段,研究采用LSB法实现重要目标遥感图像信息的隐藏,实验证明该方法可以有效地解决网上图像传输出现的安全问题. 相似文献
7.
1 Introduction Soil is not only the major natural resource on which human being depends for the production of food, feed, fiber, renewable energy and raw materials, but also plays a key role in maintaining the complex terrestrial ecosystems and climate systems of this planet. Recent rapid increase in the human population is placing a great strain on the worlds soil resources. Only about 11% of the global land surface covered by the soils are being used to raise crops and livestock, in other … 相似文献
8.
Paul Barter 《Singapore journal of tropical geography》2002,23(3):268-287
This paper explores links between transport and housing security issues for the urban poor using the example of the Klang Valley in Malaysia. The interface between these issues is identified as a gap in the literature, including policy debates, on both housing and transport. A number of linkages are shown to be important and likely to be relevant in many cities of the South, especially those with rapid motorisation and large numbers of "squatters". A simple framework for understanding these linkages is presented. Key examples include displacement to make way for transport infrastructure and the impact on transport problems for the poor of policies affecting the location of urban poor housing, including relocation sites and transit accommodation. The case study of the Klang Valley is used to illustrate and test the relevance of a focus on this issue and the utility of the conceptual framework. Some policy implications of the investigation and case study are suggested. 相似文献
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10.
蔡福根 《云南地理环境研究》1996,8(2):28-33
本文概述了地理信息系统在我国的兴起和发展及其国外背景和应用前景。论述了数据产品在地理信息系统中的重要性及其标准化的重要性和必要性。简单地提出了标准化的解决方法,以便参考。从而呼请有关部门对这一实际问题给予足够的重视。 相似文献