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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

Randomization of classical inference patterns and its application

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Science in china(Series F) 2007年第6期50卷 867-877页

作者： WANG GuoJun1,2 & HUI xiaoJing1,31 Institute of Mathematics, Shaanxi Normal university, xi’an 710062, china 2 Research Center for Science, xi’an jiaotong university, xi’an 710049, china 3 College of Mathematics and Computer Science, Yan’an university, 716000, china 1. Institute of Mathematics Shaanxi Normal University Xi’an 710062 China 2. Research Center for Science Xi’an Jiaotong University Xi’an 710049 China 3. College of Mathematics and Computer Science Yan’an University 716000 China

By means of randomization, the concept of D-randomized truth degree of formulas in two-valued propositional logic is introduced, and it is proved that the set of values of D-randomized truth degree of formulas has no isolated point in [0,1]. The concepts of D-logic pseudo-metric and D-logic metric space are also introduced and it is proved that there is no isolated point in the space. The new built D-randomized concepts are extensions of the corresponding concepts in quantified logic. Moreover, it is proved that the basic logic connectives are continuous operators in D-logic metric space. Lastly, three different types of approximate reasoning patterns are proposed.

关键词： D-randomized mapping D-randomized truth degree D-similarity D-logic metric space approximate reasoning

A k-ε Turbulence Model Considering Compressibility in Three-Dimensional Transonic Turbulent Flow Calculation

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Journal of Thermal Science 2000年第2期9卷 97-102页

作者： Guojun LI Zhenping FENG Moujin ZhANG Liang LI (school of Energy & Power Engineering, xi’an jiaotong university, xi’an 710049, china) school of Energy and Power Engineering Xi'an Jiaotong University Xi'an 710049 China

Based on the standard k-ε turbulence model, a new compressible k-ε model considering the pressure expansion influence due to the compressibility of fluid is developed and applied to the simulation of 3D transonic turbulent flows in a nozzle and a cascade. The Reynolds avenged N-S equations in generalized curvilinear coordinates are solved with implementation of the new model. The high resolution TVD scheme is used to discretize the convective terms. The numerical results show that the compressible k-ε model behaves well in the simulation of transonic internal turbulent flows.

关键词： k-ε turbulence model 3D transonic flows TVD scheme numerical simulation.

Torque effect on vibration behavior of high-speed train gearbox under internal and external excitations

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Railway Engineering Science 2024年第2期32卷 229-243页

作者： Yue Zhou xi Wang Hongbo Que Rubing Guo xinhai Lin Siqin Jin Chengpan Wu Yu Hou school of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China CRRC Qishuyan Institute Co. Ltd.No.258Wuyi RoadQishuyanChangzhou 213011China Frontiers Science Center for Smart High-Speed Railway System Beijing Jiaotong UniversityBeijing 100044China

The high-speed train transmission system,experiencing both the internal excitation originating from gear meshing and the external excitation originating from the wheel-rail interaction,exhibits complex dynamic behavior in the actual service *** paper focuses on the gearbox in the high-speed train to carry out the bench test,in which various operat-ing conditions(torques and rotation speeds)were set up and the excitation condition covering both internal and external was *** responses on multiple positions of the gearbox were acquired in the test and the vibration behavior of the gearbox was ***,a stochastic excitation modal test was also carried out on the test bench under different torques,and the modal parameter of the gearbox was ***,the sweep frequency response of the gearbox under gear meshing excitation was analyzed through dynamic *** results showed that the torque has an attenuating effect on the amplitude of gear meshing frequency on the gearbox,and the effect of external excitation on the gearbox vibration cannot be ignored,especially under the rated operating *** was also found that the torque affects the modal param-eter of the gearbox *** torque has a great effect on both the gear meshing stiffness and the bearing stiffness in the transmission system,which is the inherent reason for the changed modal characteristics observed in the modal test and affects the vibration behavior of the gearbox consequently.

关键词： High-speed train Gearbox Bench test Vibration behavior Modal identification

Crystal structures and electronic properties of BaC_2 isomers by theoretical study based on DFT

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Science china Chemistry 2008年第6期51卷 545-550页

作者： FENG Jing1,xiAO Bing2 & CHEN JingChao1 1 Key Laboratory of Advanced Materials of Precious-Nonferrous Metals,Education Ministry of china,and Key Lab of Advanced Materials of Yunnan Province,Kunming university of Science and Technology,Kunming 650093,china 2 school of Materials Science and Engineering,xi’an jiaotong university,xi’an 710049,china 1. Key Laboratory of Advanced Materials of Precious-Nonferrous Metals Education Ministry of China Kunming China 3. Key Lab of Advanced Materials of Yunnan Province Kunming University of Science and Technology Kunming 650093 China 2. school of Materials Science and Engineering Xi’an Jiaotong University Xi’an 710049 China

Band structures and electronic properties of two BaC2 isomers were calculated by using density func-tional theory(DFT) *** ionic bond features are all typical between cation(Ba) and anion clusters(C2) in both structures of the ***,a much stronger covalent bond exists in anion clusters which can be seen by inspecting the electron distribution contour that has a dull bell like shape between two carbon *** shortest distance between Ba2+ and C22? and the bond length in anion clusters are different in these isomers of BaC2,which are 0.2945 nm and 0.1185 nm for the structure with the I4/mmm space group and 0.2744 and 0.1136 nm with the C2/c type,*** structures were clarified by combining the DOS to indicate the ionic bonding features more *** analysis provided further evidence on these *** calculation results reveal that the transition temperature of these two polymorphs of BaC2 locates near 132 K,which is consistent with the recent experimental results.

关键词： functional materials metal diaries phase transition electron density first principle calculation orbital bonding state

DNA splice site sequences clustering method for conservativeness analysis

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Progress in Natural Science:Materials International 2009年第4期19卷 511-516页

作者： Quanwei Zhang, Qinke Peng, Tao Xu State Key Laboratory for Manufacturing Systems Engineering, school of Electronic and Information Engineering, xi’an jiaotong university, xi’an 710049, china [a]State Key Laboratory for Manufacturing Systems Engineering School of Electronic and Information Engineering Xi’an Jiaotong University Xi’an 710049 China

DNA sequences that are near to splice sites have remarkable conservativeness, and many researchers have contributed to the prediction of splice site. In order to mine the underlying biological knowledge, we analyze the conservativeness of DNA splice site adjacent sequences by clustering. Firstly, we propose a kind of DNA splice site sequences clustering method which is based on DBSCAN, and use four kinds of dissimilarity calculating methods. Then, we analyze the conservative feature of the clustering results and the experimental data set.

关键词： Bioinformatics processing Clustering DBSCAN Splice site

Experimental Investigation on Local Air Age and Air Distribution of Stratum Ventilation

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湖南大学学报（自然科学版） 2009年第S1期36卷 35-39页

作者： WANG Feng-hao,LI Yuan-bin,LIU xiao-dong,WANG xin-ke(school of Human Settlements and Civil Engineering,xi’an jiaotong university,xi’an,Shaanxi 710049,china) school of Human Settlements and Civil Engineering Xi'an Jiaotong University Xi'an 710049 China

Because of the multiple problems on high energy consumption and unbalanced thermal comfort caused by the traditional ventilation system,a new concept of ventilation-stratum ventilation has been proposed,which sends the fresh air to the breathing zone *** this paper,the local air distributions of the displacement ventilation and the stratum ventilation in a model office were *** air ages in the breathing zone for the displacement ventilation and stratum ventilation were compared with the tracer gas concentration decay *** decay curves of tracer gas concentration for these two ventilation systems in the breathing zone were obtained,and the air ages were *** experimental results show that the stratum ventilation system can offer lower air age for four mechanically ventilated cases in the breathing zone,and it can also provide better thermal comfort,which renews the air of breathing zone more quickly and reduces the energy consumption in some *** experimental investigation provides a theoretical basis for the application of stratum ventilation system.

关键词： ventilation air quality air age distribution

Ceramics Surface Modification by Excimer Laser Metal Coating

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Journal of Materials Science & Technology 1994年第6期10卷 463-465页

作者： Weidou ZHU and Haicheng GU(Dept. of Materials Science and Engineering, xi’an jiaotong university, xi’an, 710049, china) xi'an jiaotong Univ Xi'an China

Thin metallic layers (~ 2 μm) of Ni were deposited on polycrystalline Al2O3. ZrO2 and (Ce-TZP)+Al2O3 ceramic substrates. and further irradiated with pulsed excimer (Xeno chloride) laser pulses. The laser energy density was varied from 0.21 to 0.81 J / cm2 to optimize bending strength. For ZrO2 ceramic, it was found that the strength increases from 530 to 753 MPa at 0.51 J / cm2 irradiation. For Al2O3 and (Ce-TZP)+ Al2O3 the fracture strength also increases in varying degree. The causes of strength increment were discussed.

关键词： Ceramics Surface Modification by Excimer Laser Metal Coating Res

Binary particle swarm optimization with multiple evolutionary strategies

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Science china(Information Sciences) 2012年第11期55卷 2485-2494页

作者： ZHAO Jing1,HAN ChongZhao1 & WEI Bin2 1Ministry of Education Key Lab For Intelligent Networks and Network Security,State Key Laboratory for Manufacturing Systems Engineering,Institute of Integrated Automation,school of Electronics and Information Engineering,xi'an jiaotong university,xi'an 710049,china 2Institute of System Engineering,school of Electronics and Information Engineering,xi'an jiaotong university,xi'an 710049,china 1. Ministry of Education Key Lab For Intelligent Networks and Network Security State Key Laboratory for Manufacturing Systems Engineering Institute of Integrated Automation School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an 710049 China2. Institute of System Engineering School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an 710049 China

This paper introduces a novel variation of binary particle swarm optimization(BPSO) algorithm and a further extension to improve its ***,mimicking the behaviors of some creatures group,multiple evolutionary strategies BPSO(MBPSO) is introduced which takes different evolutionary strategies for various particles according to their ***,on the basis of MBPSO,a new strategy is discussed to improve the performance of the MBPSO(M2BPSO) which adopts the concept of the mutation operator aiming to overcome the premature convergence and slow convergent speed during the later stages of the *** proposed two algorithms are tested on seven benchmark functions and their results are compared with those obtained by other *** results show that our methods outperform the other algorithms.

关键词： binary particle swarm optimizer evolutionary strategies swarm intelligence