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Development and Application of High Performance X80 Line Pipe for the 2^(nd) West-East Gas Pipeline

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Journal of Iron and Steel Research International 2011年第S1期18卷 39-48页

作者： LI He-lin 1 , HUO Chun-yong 1 , JI Ling-kang 1, 2 , LI Yang 1, 3 (1. CNPC Tubular Goods Research Institute, Xi’an 710065, china 2. . school of Material Science and Engineering, Xi’an jiaotong university, Xi’an 710049, china 3. school of Material Science and Engineering, university of Science and Technology beijing, beijing 100083, china) CNPC Tubular Goods Res Inst Xian 710065 Peoples R China Xi An Jiao Tong Univ Sch Mat Sci & Engn Xian 710049 Peoples R China Univ Sci & Technol beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

It is the development tendency of gas pipeline to improve strength of line pipe and transmission pressure, which is an important symbol of the progress of gas pipeline technology. The 2nd West-East Gas Pipeline (the 2 nd WEGP) is the largest-scale X80 high pressure gas pipeline project in the world. Through the joint development project by Pipeline Company, research institute, and steel company, a series of achievements of technology have been obtained, which makes it possible to apply pressure of 12 MPa and X80 LSAW and HSAW pipe for the 2 nd WEGP. Specifications of X80 steel and pipe have been issued based on API 5L. High performance X80 steel and pipe have been developed and meets the Specification. General design conception of applying HSAW pipe and LSAW pipe on gas transmission trunk line with large diameter and high pressure has been established. Failure control of the 2 nd WEGP has been carried out to avoid failure and reduce the lost which based on analysis of pipeline failure mode. In this paper, research and development of high performance X80 welded pipe, establishment of technical route of joint application of HSAW and LSAW steel pipe and key technology of failure control are emphatically discussed.

关键词： 2 nd WEGP acicular ferrite failure control arrest toughness strain-based design

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基于知识约束的空车调整优化方法研究

铁道学报 2003年第6期25卷 14-20页

作者：张喜张全寿北京交通大学交通运输学院北京100044

铁路空车调整是一个集空车O D量(调配方案)生成与车流径路分配于一体的复杂的铁路网流量分配问题。由于实际的空车调整计划将受到许多模糊或不确定因素的影响,需要凭借专家知识或经验来确定,所以如何基于知识建立空车调整问题的优化模... 详细信息

铁路空车调整是一个集空车O D量(调配方案)生成与车流径路分配于一体的复杂的铁路网流量分配问题。由于实际的空车调整计划将受到许多模糊或不确定因素的影响,需要凭借专家知识或经验来确定,所以如何基于知识建立空车调整问题的优化模型及算法是一个重要的研究课题。本文基于空车调配满足最小费用和路网中流量合理分布的综合评价原则,通过引入知识约束的概念,构造了一个带混合约束(数学约束+知识约束)的优化模型,并结合铁路空车调整计划的实际,采用模糊定量化指标的方法,对模型的求解提出一个应用算法。

关键词：空车调整知识约束优化模型优化算法

Optimal Higher Order Learning Adaptive Control for a Class of SISO Nonlinear Systems

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Optimal Higher Order Learning Adaptive Control for a Class o...

第二十四届中国控制会议

作者： Chi Ronghu~1, Hou Zhongsheng~2 (1. school of traffic and transportation of beijing jiaotong university, beijing 100044 china) (2. school of Electronics and Information Engineering of beijing jiaotong university, beijing 100044 china)

＜正＞ In this paper, an optimal higher order learning adaptive control is developed for a class of SISO nonlinear systems. The design is model-free, just based directly on pseudo-partial-derivatives derived on-line from the input and output information of the system. A novel weighted one-step-ahead control criterion function is proposed for the control law. The convergence analysis is given and it shows that the proposed control law can guarantee the convergence under the assumption that the desired output is a set point. Compared with the one order learning adaptive control method, simulation examples are provided for nonlinear systems to show the better performance of the higher order learning adaptive control.

关键词： optimal higher order learning adaptive control model-free convergence nonlinear system

The Influence of Preheat Temperature of Steel Plate on Steel-mushy Cu-graphite Bonding

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Journal of Wuhan university of Technology(Materials Science) 2006年第3期21卷 12-14页

作者：张鹏 Department of Mechanical Engineering Beijing Jiaotong UniversityBeijing 100044China

The pressing bonding of steel plate to QTi3.5-3.5 graphite slurry was conducted. Under the conditions of 530 ℃ for the preheat temperature of dies, 45% for the solid fraction of QTi3.5- 3.5 graphite slurry, 50 MPa for the pressure and 2 min for the pressing time, the relationship between the preheat temperature of steel plate and interfacial mechanical property of bonding plate was studied. The results show that when the preheat temperature of steel plate is lower titan 618 ℃ , the interfacial shear strength of bonding plate increases with the increasing of the preheat temperature of steel plate. When the preheat temperature of steel plate is higher than 618 ℃ , the interfacial shear strength decreases with the increasing of the preheat temperature of steel plate. When the preheat temperature of steel plate is 618 ℃ , the highest interfacial shear strength of bonding plate of 127.8 MPa can be got.

关键词： steel-mushy QTi3.5-3.5 graphite pressing bonding interfacial shear strength preheat temperature of steel plate

A PCA-based method for ancestral informative markers selection in structured populations

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Science china(Life Sciences) 2009年第10期52卷 972-976页

作者： ZHANG Feng1,3, ZHANG Lei1,3 & DENG Hong-Wen1,2,3 1 Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Molecular Genetics, school of Life Science and Technology, Xi’an jiaotong university, Xi’an 710049, china 2 Institute of Bioscience and Biotechnology, school of Science, beijing jiaotong university, beijing 100044, china 3 Departments of Orthopedic Surgery and Basic Medical Science, school of Medicine, university of Missouri-Kansas City, Kansas City, MO 64108, USA 1. Key Laboratory of Biomedical Information Engineering of Ministry of Education Institute of Molecular Genetics School of Life Science and Technology Xi’an Jiaotong University Xi’an 710049 China 3. Departments of Orthopedic Surgery and Basic Medical Science School of Medicine University of Missouri-Kansas City Kansas City MO 64108 USA 2. Institute of Bioscience and Biotechnology School of Science Beijing Jiaotong University Beijing 100044 China

Identification of population structure can help trace population histories and identify disease genes. Structured association (SA) is a commonly used approach for population structure identification and association mapping. A major issue with SA is that its performance greatly depends on the informa-tiveness and the numbers of ancestral informative markers (AIMs). Present major AIM selection meth-ods mostly require prior individual ancestry information, which is usually not available or uncertain in practice. To address this potential weakness, we herein develop a novel approach for AIM selection based on principle component analysis (PCA), which does not require prior ancestry information of study subjects. Our simulation and real genetic data analysis results suggest that, with equivalent AIMs, PCA-based selected AIMs can significantly increase the accuracy of inferred individual ancestries compared with traditionally randomly selected AIMs. Our method can easily be applied to whole genome data to select a set of highly informative AIMs in population structure, which can then be used to identify potential population structure and correct possible statistical biases caused by population stratification.

关键词： population structure principle component analysis ancestral informative markers

Modeling Transport Hub Layout Using Bi - Level and Game Theory

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Modeling Transport Hub Layout Using Bi - Level and Game Theo...

2005全国博士生学术论坛（交通运输工程学科）

作者： Li Deweil , Han Baoming (school of traffic and transportation, beijing jiaotong university, beijing 100044)

＜正＞ This paper provides an optimized bi - level model for transport hub layout problem based on urban rail transit network. Two factors are considered, the total time saved in the whole traffic network and the competition - cooperation re lationships between different transportation modes. Thus, the paper mainly focuses on the two problems, one is to minimize the total travel time and mode change of all transit users and the other is to maximize the profit of each transport modes companies by use of game theory. This paper also deals with the relationsh ip among passenger waiting time, in - vehicle time, service frequency and traffic demand. A long run microcosmic " non - zero - sum" game model is put forward to solve the complex collaborative problem of transport modes . Finally, an example is presented on a predicted multi - modal network.

关键词： transit bi-level game theory hub Layout

An MPEC Model and a Locally Convergent Algorithm for the ContinuousNetwork Design Problem

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An MPEC Model and a Locally Convergent Algorithm for the Con...

2005全国博士生学术论坛（交通运输工程学科）

作者： Zhao Hui, Gao Ziyou (school of traffic and transportation, beijing jiaotong university, beijing 100044)

＜正＞ The continuous network design problem （CNDP） is one of the most difficult and interesting problems in transportation. It deals with the selection of link improvement to an existing road network, with given demand from each origin to each destination. The traditional model is introduced by taking advantage of the bilevel programming. A more generalized model is the mathematical programming with equilibrium constraints （MPEC）, and the bilevel programming model can be seen as a special case. In this paper, we proposed a locally convergent algorithm for the MPEC model for the CNDP and illustrated the applications of the new algorithm with a numerical example.

关键词： network design mathematical programming with equilibrium ocnstraints optimization netwak equilibrium

Modeling Comprehensive transportation Based on Bi-level Programming andGame theory

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Modeling Comprehensive Transportation Based on Bi-level Prog...

2005全国博士生学术论坛（交通运输工程学科）

作者： Zhang Chen, Hu Siji (school of traffic and transportation, beijing jiaotong university, beijing 100044)

＜正＞ In comprehensive transportation market, every mode of transportation is in competition with each other. It is, therefore, the duty of the government to make a proper investment plan for the construction of the comprehensive transportation system （CTS） in order to avoid irrational competition for the entire system. In this paper, based on the technique of Bi - level programming and Game theory, a model of the CTS investment problem is presented, and we develop a heuristic algorithm to solve this problem. Moreover, a simple numerical example is given. The result indicates that only appropriate investment planning and harmonious development of different modes of transportation can benefit the whole society.

关键词： comprehensive transportation bi- level programming game theory

Railway Capacity Calculation Based on Auto-Drawing Train Working Diagram and Computer Simulation

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Railway Capacity Calculation Based on Auto-Drawing Train Wor...

2011高等职业教育电子信息类专业学术暨教学研讨会

作者： Jinjin TANG,Leishan ZHOU,Lu TONG school of traffic and transportation of beijing jiaotong university,beijing,china,100044

It reviews the main methods of the study of railway capacity in the *** in china,the defini- tion of railway capacity is different from the other countries,so the main methods of calculating railway capacity are not suit to Chinese *** introduce the coefficient of removal analysis method to calculate the capacity of railway with automatic block section,but its calculating result isn’t *** computer technology improves,the auto-drawing train working diagram(TWD)has become a *** proposes a new approach to calculate the railway capacity,and the calculating method is based on auto-drawing TWD and computer *** goal of this new method is to draw the maximum number of common freight train paths into the original timetable where passenger train paths and important freight train paths are exist and fixed.

关键词： railway capacity computer simulation train working diagram calculating method