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基于GA-BPNN的铁路站房结构工程投资估测研究
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作者 魏庆朝 闫松涛 +1 位作者 时瑾 杨娜 《铁道工程学报》 EI 北大核心 2014年第5期95-100,共6页
研究目的:近年来,随着我国客运专线、城际铁路的迅速发展,一大批现代化的铁路客站也已建成或者在建中。为更好适应今后铁路客站发展趋势及客站建设工作需要,进一步加强铁路客站工程投资控制方面的研究,对新建铁路客站站房工程投资的估... 研究目的:近年来,随着我国客运专线、城际铁路的迅速发展,一大批现代化的铁路客站也已建成或者在建中。为更好适应今后铁路客站发展趋势及客站建设工作需要,进一步加强铁路客站工程投资控制方面的研究,对新建铁路客站站房工程投资的估测进行研究是十分有必要的。研究结论:本文通过对铁路客站站房结构工程投资的影响因素及估测模型进行研究,得到以下结论:(1)基于收集到的大量铁路客站站房结构及工程投资基础数据,分析得到铁路客站站房结构工程投资的主要影响因素为站房面积、基底面积、站房建筑高度、抗震设防烈度、楼盖柱的结构高度、楼盖结构投影面积,并将其作为输入向量建立了BP神经网络估测模型;(2)应用GA遗传算法对BP神经网络模型的初始权值阈值进行了优化,通过估测结果对比,估测模型的精度及泛化能力都得到了显著提高;(3)通过工程实例对模型进行验证,估测模型得到的结果同概算值相对误差为1.19%,符合工程项目前期估算的精度要求,进一步验证了铁路客站站房结构工程投资估测模型的工程实用性;(4)本文研究内容可为相关研究领域提供一定的借鉴,同时对铁路客站站房结构工程投资控制研究具有一定的参考意义。 展开更多
关键词 铁路站房 工程投资 估测研究 GA—BPNN
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基于模糊数学方法的铁路客运站站房结构造价快速估算研究 被引量:2
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作者 吴建平 成泉 《铁道运输与经济》 北大核心 2011年第12期55-59,共5页
以侧式站房为例,利用模糊数学方法研究快速估测铁路客运站站房结构造价。分析铁路客运站站房结构造价快速估测步骤和流程,依托大量已建铁路客运站的工程数据资料,随机选取4个样本对理论进行检验。检验结果表明计算误差可以控制在5%以内... 以侧式站房为例,利用模糊数学方法研究快速估测铁路客运站站房结构造价。分析铁路客运站站房结构造价快速估测步骤和流程,依托大量已建铁路客运站的工程数据资料,随机选取4个样本对理论进行检验。检验结果表明计算误差可以控制在5%以内,说明模糊数学分析方法可以为铁路客运站项目的评估及决策提供参考依据。 展开更多
关键词 铁路客运站 模糊数学 侧式站房 结构费用 估测研究
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On the Bergman representative coordinates 被引量:2
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作者 DINEW Zywomir 《Science China Mathematics》 SCIE 2011年第7期1357-1374,共18页
We study the set where the so-called Bergman representative coordinates (or Bergman functions) form an immersion. We provide an estimate of the size of a maximal geodesic ball with respect to the Bergman metric contai... We study the set where the so-called Bergman representative coordinates (or Bergman functions) form an immersion. We provide an estimate of the size of a maximal geodesic ball with respect to the Bergman metric contained in this set. By concrete examples we show that these estimates are the best possible. 展开更多
关键词 representative coordinates Bergman metric geodesic ball Lu Qi-Keng conjecture Hermitian geometry
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Research Framework for Ecosystem Vulnerability:Measurement, Prediction, and Risk Assessment 被引量:2
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作者 WANG Yajun ZHONG Lifang 《Journal of Resources and Ecology》 CSCD 2020年第5期499-507,共9页
The fragility of ecosystem health has become a key factor hindering the sustainable development of the ecological environment. Through a review of published research from domestic and foreign scholars, starting from t... The fragility of ecosystem health has become a key factor hindering the sustainable development of the ecological environment. Through a review of published research from domestic and foreign scholars, starting from the endogenous logic of studies in the field of ecosystem vulnerability(EV), this paper sorts out the literature on the aspects of measurement models, prediction methods and risk assessment, comprehensively defines the research category and scientific framework of EV, and analyzes the research ideas and development trends. We arrived at the following conclusions: 1) The connotation of ecosystem vulnerability not only embodies the change in the vulnerability of the natural environment, but it also reflects the irreversible damage to the ecosystem caused by excessive development and industrial production activities. 2) The setting of ecosystem vulnerability indices should aim to fully reflect the essential features of that vulnerability, which should include the index systems of natural, social, economic and other related factors. 3) There are many types of ecosystem vulnerability measurement methods, prediction models and risk evaluation models, which have different focuses and advantages. The most appropriate method should be adopted for conducting comprehensive and systematic evaluation, prediction and estimation according to the different representation and evolution mechanisms of the chosen research object and regional ecosystem vulnerability. 4) Based on the regional system characteristics, corresponding risk management measures should be proposed, and pertinent policy suggestions should be put forward to improve the ecological safety and sustainable development of an ecologically vulnerable area. 展开更多
关键词 ecosystem vulnerability measurement PREDICTION risk assessment research framework PROSPECTS
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