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A Railway Power Quality Conditioner Based on Chain Circuit Using Impedance-matching Balance Transformers

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A Railway Power Quality Conditioner Based on Chain Circuit U...

2011 International Conference on Advanced Power System Automation and Protection(APAP 2011)

作者： Ding Na 1 2 Shu Zeliang 1 2 Guo Yuhua 1 2 1 Key Laboratory of Magnetic suspension Technology and Maglev Vehicle Ministry of Education chengdu 61003. china 2 school of Electrical {3. southwest jiaotong university chengdu 61003. sichuan china

In order to compensate reactive power and eliminate the negative-sequence and harmonic currents of electrified railway system, a new railway power compensator （RPQC） is proposed. The RPQC consists of three single-phase voltage source converters based on the chain circuit inverters. It connects the railway traction power system directly without isolation transformer. Power rating of the conditioner can be increased simply by adding chain links in series. The proposed topology is suitable for traction power system with impedance-matching balance transformer. Regarding the traction substation as a control object, the power quality of the traction substation with RPQC can be improved integrally. The RPQC always makes the traction substation become a nearly balanced three-phase power system in the public grid whether the loads of two feeders are balanced or not. According to simulation results, the proposed RPQC is feasible, and it can compensate reactive power, harmonic, and negative-sequence currents in two feeders together.

关键词： power quality electric railway traction substation chain circuit

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方柱绕流的数值模拟

力学季刊 2002年第1期23卷 77-81页

作者：童兵祝兵周本宽西南交通大学工程科学研究院四川成都610031

采用有限差分法,对雷诺数为2.2×104的方柱绕流进行了大涡模拟(简称LES).运用时间分裂控制(Split-Operator)法,将N-S方程分为对流步、扩散步和传播步.对Smagorinsky假设在近壁区的发散问题用两层模型进行处理.对流项用迎风-中心差分格... 详细信息

采用有限差分法,对雷诺数为2.2×104的方柱绕流进行了大涡模拟(简称LES).运用时间分裂控制(Split-Operator)法,将N-S方程分为对流步、扩散步和传播步.对Smagorinsky假设在近壁区的发散问题用两层模型进行处理.对流项用迎风-中心差分格式模拟,压力方程用SOR法迭代求解.计算得到的沿对称线的时均顺流向速度与文献上的实验结果进行了比较,结果吻合较好;同时还对绕方柱流的流场结构进行了分析研究.

关键词：湍流数值模拟大涡模拟绕钝状体流

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南昆铁路某滑坡变形的灰色预测

四川大学学报（工程科学版） 2003年第4期35卷 22-24页

作者：赵志明西南交通大学土木工程学院四川成都610031

根据南昆(南宁—昆明)铁路某滑坡实际情况,运用灰色理论和方法通过模型的建立、模型修正、精度检验过程得出用于预测滑坡变形的GM(1,1)模型,并用该模型对其部分监测点的空间位移进行了预测。预测结果与实测值完全吻合,证明此模型在实际... 详细信息

根据南昆(南宁—昆明)铁路某滑坡实际情况,运用灰色理论和方法通过模型的建立、模型修正、精度检验过程得出用于预测滑坡变形的GM(1,1)模型,并用该模型对其部分监测点的空间位移进行了预测。预测结果与实测值完全吻合,证明此模型在实际工程中应用是可行的。

关键词：灰色系统 GM(1,1)模型预测南昆铁路滑坡变形

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高速以太网时延仿真分析

计算机科学 2011年第B10期38卷 341-344页

作者：杨佳丽窦军西南交通大学信息科学与技术学院成都610031

随着以太网技术的不断发展,以太网已成为未来通信领域的核心技术之一。而影响用户业务体验服务质量(QoS)的参数通常包括时延、抖动、丢包率等。对于实时的语音和视频业务来说,业务数据的端到端时延则最为关键。主要在熟悉以太网标准的... 详细信息

随着以太网技术的不断发展,以太网已成为未来通信领域的核心技术之一。而影响用户业务体验服务质量(QoS)的参数通常包括时延、抖动、丢包率等。对于实时的语音和视频业务来说,业务数据的端到端时延则最为关键。主要在熟悉以太网标准的基础上,总结端到端时延的主要构成因素,对各个时延所占比重进行理论分析。最后对10G/100G以太网进行仿真模型设计,验证了理论分析的正确性。

关键词： 10G/40G/100G以太网端到端模型服务质量时延队列调度算法

Experimental Study on Bearing Features of Bored Pile under Non-refreezing Condition in Permafrost Region

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Experimental Study on Bearing Features of Bored Pile under N...

第一届交通运输工程国际学术会议

作者： YU Zhi-qiang1, WANG Xu2, and JIANG Dai-jun2 1school of Civil engineering, southwest jiaotong university, {3. 61003., china 2school of Civil engineering, Lanzhou jiaotong university, Lanzhou 73.070, china

Facing the problems such as pile cap and bridge pier construction, super structure construction, time limit for construction etc, a key problem is to solve the bearing capacity and deformation of large diameter bored pile under non-refreezing condition. In-situ experiment was carried out at high-temperature in fine-granular frozen soil region of Qinghai-Tibet plateau. On the basis of ground temperature data and in-situ experimental data, the authors analyzed the shaft resistance and tip resistance of the pile under different ground temperature conditions. In the meantime, the authors also analyzed the deformation features of non-refreezing large diameter bored pile in permafrost. The experimental results can be used as some guides and references in the process of pile foundation construction.

关键词： permafrost high temperature fine-granular frozen soil cast-in-place bored pile ground temperature axial bearing features

Research on RosettaNet Standards for Information Sharing of Heterogeneous Systems based on E-HUB

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Research on RosettaNet Standards for Information Sharing of ...

2007北京地区高校研究生学术交流会通信与信息技术会议

作者： Zhou Guixian~1 Xie Qingsheng~2 1 school of mechanical Engineer..southwest jiaotong university,sichuan,{3.,61003.,china 2 Guizhou university,Modern Manufacturing Technology Key Laboratory,Guiyang,550003.china

The paper study the theoretics and methods about the E-HUB *** analyzing the issues of standardization and existing standards for heterogeneous information sharing,such as *** paper provides researching results of standardization related to the heterogeneous system and critical technology base on E-HUB platform to implement the solution.

关键词： RosettaNet Heterogeneous Information E-HUB platform

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对城市生活垃圾填埋处置技术的思考

四川环境 2004年第3期23卷 60-63页

作者：曹霞刘丹西南交通大学环境科学与工程学院四川成都610031

本文分析了我国广泛使用的垃圾填埋技术———厌氧卫生填埋的缺点,介绍了当前新型的填埋技术———生物反应器填埋技术、好氧填埋技术、准好氧填埋技术、循环式准好氧填埋的原理、结构及各自的优缺点,据此指出我国今后垃圾填埋技术的研... 详细信息

本文分析了我国广泛使用的垃圾填埋技术———厌氧卫生填埋的缺点,介绍了当前新型的填埋技术———生物反应器填埋技术、好氧填埋技术、准好氧填埋技术、循环式准好氧填埋的原理、结构及各自的优缺点,据此指出我国今后垃圾填埋技术的研究方向。

关键词：垃圾填埋处置生物反应器填埋准好氧填埋循环式准好氧填埋

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水力失调问题的一种解决方案

西华大学学报（自然科学版） 2003年第S1期22卷 61-64页

作者：杨霄西南交通大学机械工程学院四川成都610031

本文作者利用有关图论、流体网络技术及线性规划中灵敏度分析对现代建筑及工程中常见的水力失调问题进行了分析和探讨 ,并制定了一套简单、有效的解决方案。最后通过实例给出了这一方案的实施步骤及结果。

关键词：水力失调图论管网灵敏度分析

Modeling for Giant Magnetostrictive Actuators with Rate-Dependent Hysteresis based on Hammerstein-like System by Using LS-SVM

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Modeling for Giant Magnetostrictive Actuators with Rate-Depe...

第24届中国控制与决策会议

作者： Ping Liu 1 , Zhen Zhang 1 , Jianqin Mao 1 , Kemin Zhou 2 , 1. school of Automation science and Electrical engineering, Beijing {3. of Aeronautics & Astronautics, Beijing 1001912. school of Electrical engineering, southwest jiaotong university, chengdu, sichuan 61003.

The rate-dependent hysteresis in giant magnetostrictive materials is a major impediment to the application of such material in actuators . In this paper, a Hammerstein-like model based on Least Square Support Vector Machines （LS-SVM） is proposed to model the rate-dependent hysteresis system. We show that it is possible to construct a unique dynamic model in a given frequency range for a rate-dependent hysteresis system using the sinusoidal scanning signals as the training set of signals for the linear dynamic subsystem of the Hammerstein-like model, which guarantees an outstanding generalization ability of frequency. The LS-SVM parameters influencing the model accuracy are determined through the intelligent particle swarm optimization （PSO） and the dimension of input data is also discussed. Simulations on a giant magnetostrictive actuator （GMA） verify both the effectiveness and practicality of the proposed modeling method.

关键词： GMA LS-SVM Hammerstein-like Hysteresis PSO Rate-dependent