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A novel algorithm of artificial immune system for high-dimensional function numerical optimization

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Progress in Natural Science:materials International 2005年第5期15卷 463-471页

作者： DU Haifeng 1,2.*, GONG Maoguo1, JIAO Licheng1 and LIU Ruochen1(1. Institute of Intelligent Information Processing and Key Laboratory of Radar Signal Processing, xidian university, xi'an 710071, china 2. {2. of Mechanical engineering, xi'an jiaotong university, xi'an 710049, china) Institute of Intelligent Information Processing and Key Laboratory of Radar Signal Processing Xidian University Xi''an 710071 China school of Mechanical engineering Xi''an Jiaotong University Xi''an 710049 China

Based on the clonal selection theory and immune memory theory, a novel artificial immune system algorithm, immune memory clonal programming algorithm (IMCPA), is put forward. Using the theorem of Markov chain, it is proved that IMCPA is convergent. Compared with some other evolutionary programming algorithms (like Breeder genetic algorithm), IMCPA is shown to be an evolutionary strategy capable of solving complex machine learning tasks, like high-dimensional function optimization, which maintains the diversity of the population and avoids prematurity to some extent, and has a higher convergence speed.

关键词： clonal selection immune memory artificial immune system evolutionary algorithms Markov chain.

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 {2. Science and engineering, xi’an jiaotong university, xi’an 710049, china 3. school of {2. 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 2.d 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

An extended numerical model of the first exothermic peak for three dimensional printed cement-based materials

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Frontiers of Structural and Civil engineering 2024年第1期18卷 80-88页

作者： Wei JIANG Wenqian LI xi CHEN school of materials Science and {2. Tongji UniversityShanghai 200092China school of Civil engineering Tongji UniversityShanghai 200092China

The first exothermic peak of cement-based material occurs a few minutes after mixing,and the properties of three dimensional(3D)printed concrete,such as setting time,are very sensitive to *** this background,based on the classical Park cement exothermic model of hydration,we propose and construct a numerical model of the first exothermic peak,taking into account the proportions of C_(3)S,C_(3)A and quicklime in *** calculated parameters are calibrated by means of relevant published exothermic test *** is found that this developed model offers a good simulation of the first exothermic peak of hydration for C_(3)S and C_(3)A proportions from 0 to 100% of cement clinker and reflects the effect of quicklime content at 8%-10%.The unique value of this research is provision of an important computational tool for applications that are sensitive to the first exothermic peak of hydration,such as 3D printing.

关键词： 3D printed cement-based materials cement hydration the first exothermic peak liquid quick-setting agent numerical model

Refractive index changes induced by sheet beams with various intensity distributions in LiNbO_(3):Fe crystal

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 399-412页

作者： ZHANG Peng1, ZHAO Jianlin1, XU Honglai1, SUN Yidong2. YANG Dexing1 & WANG Meirong1 1. Institute of Optical Information Science and Technology, school of Science, Northwestern Polytechnical university, xi’an 710072.{2. 2. school of Science, xi’an jiaotong university, xi’an 710049,{2. 1. Institute of Optical Information Science and Technology School of Science Northwestern Polytechnical University 710072 Xi’an China 2. school of Science Xi’an Jiaotong University 710049 Xi’an China

According to the Kukhtarev equations and a simplified model based on the photovoltaic charge carriers transport mechanism, the distributions of the index changes (DICs) in LiNbO3:Fe crystals induced by sheet beams with various intensity profiles are theoretically analyzed. The numerically simulated results coincide with the analytic expressions deduced from the simplified model. The DICs in a LiNbO3:Fe crystal induced by sheet beams with rectangular, Gaussian and square law profiles are measured by using the interferometric method. By employing the analytic expressions, the experimental data points are well fitted. By utilizing the angular spectrum theory and the ray equation, the uniformities of the intensity profiles of the writing beams along the propagation directions and the influences of the self-defocusing effect of the crystal are numerically simulated, respectively. The results show that the experimental results are reliable. The numerically simulated method and the analytic expressions can be both employed to predict the DICs induced by sheet beams with various light intensity profiles. Furthermore, utilizing writing beams with proper intensity profiles, any desired index distributions could be obtained.

关键词： LiNbO3:Fe crystal, light intensity profile, distribution of refractive index changes, sheet beam.

A Systematic Analysis of Early Life Exposure to the Chinese Famine(1959-1961)and the Health of Older Adults-china,2.08-2.2.

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china CDC weekly 2024年第11期6卷 203-207,I0001-I0003页

作者： Chi Shen xi Chen school of Public Policy and Administration Xi’an Jiaotong UniversityXi’an CityShaanxi ProvinceChina Department of Health Policy and Management Yale School of Public HealthNew HavenCTU.S Department of Economics Yale UniversityNew HavenCTU.S

What is already known about this topic?There is mounting evidence indicating that the aging process initiates during early life stages,with in utero the individual’s environment playing a significant ***,it is crucial to comprehend the enduring effects of early life circumstances on health in old *** is added by this report?In this study,we conducted a meta-analysis to examine the effects of the Chinese Famine(1959–1961)on the health of older *** also explored potential mechanisms underlying these *** are the implications for public health practice?The complex interplay between early life circumstances,multiple health-related sectors,and healthy aging necessitates a comprehensive life-course approach and strategic interventions to enhance public health in an aging society.

关键词： life aging mount

Novel strengthening methods for ultralightweight sandwich structures with periodic lattice cores

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Science china(Technological Sciences) 2010年第3期53卷 875-877页

作者： LU TianJian 1 &ZHANG QianCheng 2.1 MOE Key Laboratory for Strength and Vibration,school of Aerospace,xi’an jiaotong {2.,xi’an 710049,china 2.State Key Laboratory for Mechanical Behavior of materials,school of material Science and engineering,xi’an jiaotong {2.,xi’an 710049,china 1. MOE Key Laboratory for Strength and Vibration School of Aerospace Xi’an Jiaotong University Xi’an 710049 China2. State Key Laboratory for Mechanical Behavior of Materials School of Material Science and Engineering Xi’an Jiaotong University Xi’an 710049 China

Recent development of ultralightweight lattice-cored sandwiches is reviewed,with focus placed on various novel fabrication methods introduced to strengthen these structures,covering not only research results published... 详细信息

关键词： cellular metals strengthening method fabrication sandwich panels

Hybrid state estimation and model-set design of invariable-structure semi-ballistic reentry vehicle

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Science china(Information Sciences) 2011年第4期54卷 812-823页

作者： LIANG YongQi 1,2.& HAN ChongZhao 1 1 MOE KLINNS Lab,SKLMSE Lab,Institute of Integrated Automation,school of Electronics and Information engineering,xi’an {2. university,xi’an 710049,china 2.school of Aerospace,xi’an {2. university,xi’an 710049,china 1. MOE KLINNS Lab SKLMSE Lab Institute of Integrated Automation School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an 710049 China2. School of Aerospace Xi’an Jiaotong University Xi’an 710049 China

Multiple-model approach is one of the main streams for hybrid *** difficulty of this approach to estimate the hybrid state of the semi-ballistic reentry vehicle (SBRV) is model-set *** paper proposes a quasi-Monte Carlo model set that can ensure the estimator near-optimal in the sense of minimum mean square error (MMSE).The SBRV has a high nonlinearity and its mode is spanned by multiple parameters with known *** design methods and characteristics of the quasi-Monte Carlo model set are *** proposed model set has a higher accuracy than the model-set generated by the Monte Carlo *** theoretical analysis and simulation results show the effectiveness and reasonability of the newly designed model set.

关键词： semi-ballistic reentry vehicle hybrid estimation model-set design Monte Carlo method quasi-Monte Carlo method

Structural signature and contact force distributions in the simulated three-dimensional sphere packs subjected to uniaxial compression

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Science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 892-904页

作者： LIU LianFeng1,2.ZHANG Lei1 & LIAO ShuFang1 1 Department of Mathematical Sciences,xi’an jiaotong-Liverpool university,Suzhou 2.512.,{2. 2.school of Science,xi’an jiaotong university,xi’an 710049,{2. 1. Department of Mathematical Sciences Xi’an Jiaotong-Liverpool University Suzhou 215123 China2. School of Science Xi’an Jiaotong University Xi’an 710049 China

Packing of spherical particles in a three-dimensional cylindrical container is simulated by using Discrete Element *** packed bed of spheres is also subjected to vertical compression which results in a dense *** of the packing during compaction are examined in detail in terms of the contact number,deviator fabric,and radial distribution ***,contact force distributions are measured at different locations in the pack,*** centre,the side wall,and the base(or bottom wall) of the *** simulations show that random close packing(RCP) tends to exist in the centre of the pack,while ordered packing structures exist near the container's *** uniaxial compression doesn't seem to alter the packing structure in the pack centre remarkably,but to reduce the structural anisotropy of the packing close to the container's *** simulated results have also helped to establish the correlations between packing structures and contact force ***,it is shown that small contact force distributions are sensitive to local packing *** simulated results are shown to be consistent with the recent experimental and simulation findings.

关键词： packing contact force distribution discrete element method particles boundary effect

“Blocking and rebalance”mechanism-guided design strategies of bimetallic doped 2. a-phosphorus carbide as efficient catalysts for N_(2. electroreduction

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Journal of Energy Chemistry 2024年第10期97卷 68-78,I0003页

作者： Cheng He Jianglong Ma Shen xi Wenxue Zhang State Key Laboratory for Mechanical Behavior of materials School of Materials Science and EngineeringXi'an Jiaotong UniversityXian 710049ShanxiChina school of materials Science and {2. Chang'an UniversityXi'an 710064ShaanxiChina

Compared to single atom catalysts(SACs),the introduction of dual atom catalysts(DACs)has a significantly positive effect on improving the efficiency in the electrocatalytic nitrogen reduction reaction(NRR)which provides an environmental alternative to the Haber-Bosch ***,the research on the mechanism and strategy of designing bimetallic combinations for better performance is still in its early ***,based on"blocking and rebalance"mechanism,45 combinations of bimetallic pair dopedα-phosphorus carbide(TM_(A)TM_(B)@PC)are investigated as efficient NRR catalysts through density functional theory and machine learning *** a multi-step screening,the combinations of TiV,TiFe,MnMo,and FeW exhibit highly efficient catalytic performance with significantly lower limiting potentials(-0.17,-0.18,-0.14,and-0.30 V,respectively).Excitingly,the limiting potential for CrMo and CrW combinations is 0 V,which are considered to be extremely suitable for the NRR *** mechanism of"blocking and rebalance"is revealed by the exploration of charge transfer for phosphorus atoms in electron blocking ***,the descriptorφis proposed with machine learning,which provides design strategies and accurate prediction for finding efficient *** work not only offers promising catalysts TM_(A)TM_(B)@PC for NRR process but also provides design strategies by presenting the descriptorφ.

关键词： DACs Nitrogen reduction reaction 2. a-phosphorus carbide Inherent attributes Machine learning