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Roadbed Subsidence Prediction and Its Security Evaluation

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岩石力学与工程学报 2002年第9期21卷 1368-1371页

作者： Li Yongshu 1,Han Liping 2 (1 School of civil Eng.,southwest jiaotong university,chengdu 610031 china) (2 School of Computer and Comm. Eng.,southwest jiaotong university,chengdu 610031 china) School of civil Eng. Southwest Jiaotong University Chengdu 610031 School of Computer and Comm. Eng. Southwest Jiaotong Uiversity Chengdu 610031

A roadbed subsidence pattern for predicting the security of roadbed in ground subsidence area with complicated structure strata and any shape of excavations is proposed in this paper. The methods for computing the values of the movements and deformations of the roadbed characteristic points are investigated. The calculating formulae for predicting the roadbed subsidence,inclined deformation,curvature deformation,horizontal displacement and horizontal deformation are provided. The methods for evaluating roadbed security and predicting disastrous accidents of roadbed in ground subsidence area are also discussed. Finally,a practical example is given for applying the method to evaluate roadbed security.

关键词： roadbed subsidence prediction

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编组站动态配流模型与算法研究

铁道学报 2004年第1期26卷 1-6页

作者：王慈光西南交通大学交通运输学院四川成都610031

如何从众多的解体方案中选择有利方案 ,这是编组站动态配流所要解决的核心问题。本文在文献 [3 ]的基础上 ,运用组合数学原理构造方案树 ,提出最大可能剩余量概念 ,导出计算公式 ,并以此作为方案值控制树的生长 ,进而利用回溯算法搜索... 详细信息

如何从众多的解体方案中选择有利方案 ,这是编组站动态配流所要解决的核心问题。本文在文献 [3 ]的基础上 ,运用组合数学原理构造方案树 ,提出最大可能剩余量概念 ,导出计算公式 ,并以此作为方案值控制树的生长 ,进而利用回溯算法搜索有利方案。这样 ,本文连同文献 [2 ]、[3 ]一起。

关键词：编组站动态配流解体方案树最大可能剩余量回溯算法

EFFECT OF DISCHARGE RATIO ON FLOW CHARACTERISTICS IN 90°EQUAL-WIDTH OPEN-CHANNEL JUNCTION

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Journal of Hydrodynamics 2009年第4期21卷 541-549页

作者： ZHANG Ting XU Wei-lin WU Chao College of civil engineering Fuzhou University Fuzhou 350108 China State Key Laboratory of Hydraulics and Mountain River engineering Sichuan University Chengdu 610065 China

For the 90° equal-width open-channel junction flow, the Reynolds averaged Navier-Stokes equations are solved while using the 3-D κ- ω model. The mean flow pattern and the secondary current are obtained. The model is validated by experimental data, and then applied to investigate the effect of the discharge ratio on the shape of separation zone shape, the cross-sectional mean flow angle and the contraction coefficient. The results are fairly close to those of the prior studies. The numerical modeling is both less time-consuming and less expensive to obtain the various flow parameters needed for engineering design.

关键词： κ- ω turbulent model open-channel junction separation zone secondary current

Vehicle Routing Problem with Non-Full Loadof Less Freight Quantity

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Journal of Modern Transportation 1995年第1期12卷 41-50页

作者： Li Jun Guo Yaohuang(School of Ecomics and Managemnt ,southwest jiaotong university chengdu 610031 ’china)

Freight quantity is usually less than the half of vehicle capacity,and the effectiveness of transportation utilizing a single vehicle is not satisfactory enough. In this paper,a sequential heuristic algorithm is prese... 详细信息

关键词： on-full load clustering vehicle routes chaining

Application　of　Programmable　Controller　in　a　Rail　Welding　Machine

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Journal of Modern Transportation 1997年第1期14卷 80-85页

作者： Dai Hong Department of Materials engineering, southwest jiaotong university, chengdu 610031, china Xiang Junjie Long Zhuohong chengdu Rail Welding Factory, chengdu 610037, china

An innovation is conducted on a K190πK rail auto welding machine because of its poor stability in quality of welding joints. A new control system based on a programmable controller is designed to replace the old one. The new control system is of higher accuracy in controlling sequence and good ability in anti disturbance, and is convenient to operate. The comparison tests are carried out. The experimental results show that the quality of welded joints is greatly increased by the improved welding mechine.

关键词： rail welding maching programmable controller control system quality of welding joint

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基于K-均值的SVC的雷达辐射源信号识别

系统仿真学报 2008年第23期20卷 6333-6337页

作者：李序张葛祥西南交通大学电气工程学院成都610031

无监督学习是解决未知雷达辐射源信号识别的有效方法。Support Vector Clustering(SVC)是一种基于支持向量机的无监督聚类方法。SVC不仅时间复杂度高,而且在处理分布复杂、不均匀样本时,识别率较低。结合K-均值与SVC的优点,提出一种基... 详细信息

无监督学习是解决未知雷达辐射源信号识别的有效方法。Support Vector Clustering(SVC)是一种基于支持向量机的无监督聚类方法。SVC不仅时间复杂度高,而且在处理分布复杂、不均匀样本时,识别率较低。结合K-均值与SVC的优点,提出一种基于K-均值的SVC无监督聚类方法。此方法用K-均值聚类法对数据样本作初步的线性划分,将原数据样本划分成若干子样本。再将这些子样本分别映射到高维特征空间,用SVC方法去处理非线性问题。由K-均值聚类法将二次规划问题分解,大大减少SVC的计算量,降低时间消耗。相对于原数据样本,子样本的分布较为简单、均匀,容易找到更为合适的SVC参数值。对雷达辐射源信号进行聚类分析的实验结果表明,此方法处理速度较快,识别率较高。

关键词： K-均值聚类 Support Vector Clustering(SVC)无监督聚类雷达辐射源

Research on the Transfer Benefit of Railway Investment Projects

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Journal of Modern Transportation 1995年第1期12卷 16-23页

作者： Yang Jimei Xie Wei(School of Economics and Management,southwest jiaotong university,chengdu 610031,china)

Though an additional railway investment will result in very complex uifluenceon the whole economic-socinl system, an assessing system comes to be set up inthis thesis. It not only shows the seope and direction of the assessment ofrailway investment projects, but indicates a new assessment theory coming intobeins. lii view of the transfer benefit of railway investinent projects being themain part of their external benefit for our national economy, we paid specialattention to calculating the transfer benefit. Finally, a series of matheniaticalmodels throush which we can accurately figure out the transfer benefit of arailway investment project are presented.

关键词： assessing system the transfer benefit

SEEPAGE ANALYSIS OF LANDFILL FOUNDATIONS IN SHANGHAI LAOGANG LANDFILL PHASE IV

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Journal of Hydrodynamics 2006年第5期18卷 613-619页

作者： ZHANG Qian-fei WANG Yan-ming XU Yong-fu School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai 200030 China Shanghai Municipal engineering Design Institute Shanghai 200092 China

A complex seepage flow field with unknown free surface was formed in the Shanghai Laogang Municipal Solid Waste （MSW） Landfill by the perimeter cut-off wall around the landfill site and the Prefabricated Vertical Drains （PVD） in the foundation of landfill. First, the equivalent vertical permeability was presented based on the drainage mechanism of PVD and the related calculation method was studied to macroscopically reflect the impact of PVD on the seepage flow status of the landfill foundation. With the influence of the cut-off wall and the PVD on the infiltration of groundwater, the total inflow was classified into two parts： the lateral inflow through the cut-off wall outside the landfill, and the upward infiltration through the PVD from the foundation of the landfill. Seepage analysis was conducted using the finite element method according to the actual scenario of Laogang Landfill, and the lateral infiltration and the upward infiltration were calculated, respectively. The results show that the total inflow into the landfill area was mostly supplied by the upward infiltration through the PVD and the perimeter cut-off wall was significantly effective to depressurize the seepage pressure and to reduce the flow rate.

关键词： Municipal Solid Waste (MSW) landfill foundations of landfill cut-off wall Prefabricated Vertical Drain (PVD) lateral infiltration upward infiltration finite element analysis

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无缝道岔群对钢轨位移和纵向力的影响研究

铁道学报 2002年第2期24卷 74-78页

作者：王平西南交通大学土木工程学院四川成都610031

基于有限单元法 ,建立了多组无缝道岔相联结时钢轨位移和纵向力的计算分析模型 ,编制了计算软件。并以可动心轨提速道岔为例 ,分析了两组道岔的不同联结形式对钢轨位移和纵向力的影响。

关键词：无缝道岔群位移纵向力