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集装箱运输多箱三维装载优化问题的遗传算法

铁道学报 2004年第2期26卷 21-25页

作者：卜雷尹传忠蒲云西南交通大学交通运输学院四川成都610031 西南交通大学研究生院四川成都610031

作为一类组合优化问题,多约束条件下的三维装载问题属NP-hard问题,随着问题规模的不断增大,传统的优化算法在求解过程中会产生时间维数灾难问题。本文提出一种遗传算法,用于在铁路集装箱运输中优化具有放置方向、装载顺序、装载质量、... 详细信息

作为一类组合优化问题,多约束条件下的三维装载问题属NP-hard问题,随着问题规模的不断增大,传统的优化算法在求解过程中会产生时间维数灾难问题。本文提出一种遗传算法,用于在铁路集装箱运输中优化具有放置方向、装载顺序、装载质量、装载容积及重心等约束条件的货物三维装载问题,并结合方向及顺序约束采用巧妙的个体编码方法,结合装载质量、装载容积及重心约束构造合理的评价函数。实例计算表明该算法有效可行。

关键词：集装箱运输三维装载遗传算法优化

Electrophysiological evidence of personal experiences in the great Sichuan earthquake impacting on selective attention

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Science China(Life Sciences) 2009年第7期52卷 683-690页

作者： QIU Jiang1,2.LI Hong1,2.ZHANG QingLin1,2.HUANG LiHui2.GUO YaQiao2.TU Shen2.WANG Ting2.& WEI DongTao2.1 Key Laboratory of Cognition and Personality(SWU),Ministry of Education,Chongqing 400715,China 2.School of psychology,southwest University,Chongqing 400715,China Key Laboratory of Cognition and Personality (SWU) Ministry of Education Chongqing China School of psychology Southwest University Chongqing China

Event-related brain potentials(ERPs) were measured when 2. Chinese subjects performed the earthquake color-matching Stroop *** of them have experienced the great Sichuan earthquake(5.12.,with 12.subjects in each of Chengdu city and Chongqing city(different earthquake experiences) *** behavioral data showed that the earthquake Stroop task yielded robust the earthquake interference effect as indexed by longer RT for earthquake-related(Related) words than earthquake-unrelated(Unrelated) words only in the Chengdu *** ERP analysis also revealed the neurophysiological substrate of the interference effect:a greater positivity(P350-450) in Related words as compared to Unrelated words was found between 350 and 450 ms post-stimulus over fronto-central scalp regions in the Chengdu group,while the interference effect was not found in the Chongqing *** P350-450 might reflect an earthquake experience interference,but also attention enhancing,effect of earthquake-related *** source analysis of the difference wave(Related-Unrelated) showed that a generator was localized in the parahippocampal gyrus,which was possibly associated with flashbulb memory(personal earthquake experience).The results indicated that different personal earthquake experiences might be critical in engaging the neural mechanisms that underlie the modulation of selective attention.

关键词： Sichuan earthquake Stroop effect selective attention event-related potentials(ERPs)

Seismic response analysis of road vehicle-bridge system for continuous rigid frame bridges with high piers

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Earthquake Engineering and Engineering Vibration 2012年第4期11卷 593-602页

作者： Li Yongle Chen Ning Zhao Kai Liao Haili Department of Civil Engineering Southwest Jiaotong University CCCC Highway Consultants CO. Ltd.

The objective of this study is to investigate the effects of earthquakes on road vehicle-bridge coupling vibration systems. A two-axle highway freight vehicle is treated as a 13 degree-of-freedom system composed of several rigid bodies, which are connected by a series of springs and dampers. The framework of the earthquake-vehicle-bridge dynamic analysis system is then established using an earthquake as the extemal excitation. The equivalent lateral contact force serves as the judgment criteria for sideslip accidents according to reliability theory. The entire process of the vehicle crossing the bridge is considered for a very high pier continuous rigid frame bridge. The response characteristics of the vehicle and the bridge are discussed in terms of various parameters such as earthquake ground motion, PGA value of the earthquake, incident angle, pier height, vehicle speed and mass. It is found that seismic excitation is the most influential factor in the responses of the vehicle-bridge system and that the safety of vehicles crossing the bridge is seriously impacted by the dual excitations of earthquake and bridge vibration.

关键词： vehicle-bridge system coupling vibration seismic effects safety dynamic response

Emotional expectations influence neural sensitivity to fearful faces in humans:An event-related potential study

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Science China(Life Sciences) 2010年第11期53卷 1361-1368页

作者： YANG JieMin1,2. YUAN JiaJin1,2.& LI Hong1,2.1Key Laboratory of Cognition and Personality (SWU), Ministry of Education of China, Chongqing 400715, China 2.chool of Psychology, southwest University, Chongqin 400715, China Key Laboratory of Cognition and Personality (SWU) Ministry of Education of China Chongqing China School of Psychology Southwest University Chongqin China

The present study tested whether neural sensitivity to salient emotional facial expressions was influenced by emotional expectations induced by a cue that validly predicted the expression of a subsequently presented target face. Event-related potentials (ERPs) elicited by fearful and neutral faces were recorded while participants performed a gender discrimination task under cued (‘expected’) and uncued (‘unexpected’) conditions. The behavioral results revealed that accuracy was lower for fearful compared with neutral faces in the unexpected condition, while accuracy was similar for fearful and neutral faces in the expected condition. ERP data revealed increased amplitudes in the P2.component and 2.0–2.0 ms interval for unexpected fearful versus neutral faces. By contrast, ERP responses were similar for fearful and neutral faces in the expected condition. These findings indicate that human neural sensitivity to fearful faces is modulated by emotional expectations. Although the neural system is sensitive to unpredictable emotionally salient stimuli, sensitivity to salient stimuli is reduced when these stimuli are predictable.

关键词： negative bias facial emotions emotional expectation event-related potential

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贵州宝元构造嘉五~1储层裂缝预测

天然气工业 2004年第3期24卷 61-64,T001,T002页

作者：疏壮志秦启荣苏培东中国石化南方勘探开发分公司西南石油学院

从宝元构造现今构造形迹特征入手 ,利用有限元数值分析技术 ,模拟了嘉五1 储层段的古构造应力场(应力的大小、方向、性质及应力分布等值线图 ) ;然后以岩石破裂强度理论为依据 ,结合岩石的实际力学性质参数 ,计算了嘉五1 层岩体的破裂... 详细信息

从宝元构造现今构造形迹特征入手 ,利用有限元数值分析技术 ,模拟了嘉五1 储层段的古构造应力场(应力的大小、方向、性质及应力分布等值线图 ) ;然后以岩石破裂强度理论为依据 ,结合岩石的实际力学性质参数 ,计算了嘉五1 层岩体的破裂接近程度 ;以此为依据 ,对嘉五1 储层段裂缝的发育程度、类型及方位分别进行了预测。结果表明 :嘉五1 层裂缝较发育 ,主要发育在宝元构造高点部位及其附近地区 ;储层岩体在两期构造应力场作用下共形成了二期 5组裂缝 ;裂缝类型以早、晚高角度共轭剪切缝和张性缝为主 ;晚期裂缝较早期发育 ;裂缝的主要延伸方向以北西 -南东向为主。根据上述预测结果部署了 1口水平井 (宝平 1井 ) ,根据测井解释结果 ,结合气测、钻时资料分析得出的裂缝实际方位、发育位置等结果与预测完全相符。

关键词：宝元构造贵州早三叠世储集层预测裂缝有限元数值分析技术测井

Antithrombogenic investigation and biological behavior of cultured human umbilical vein endothelial cells on Ti-O film

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Science China(Technological Sciences) 2006年第1期49卷 20-28页

作者： CHEN Junying1, WAN Guojiang1, LENG Yongxiang1, YANG Ping1, SUN Hong1, WANG Jin1, HUANG Nan1, CHEN Huaiqing2.& TANG Rong2.1. College of Materials Science and Engineering, Key Laboratory of Advanced Materials Processing of Chinese Education Ministry, southwest Jiaotong University, Chengdu 610031, China 2. School of Basic Medical Sciences, West China Center of Medical Sciences, Sichuan University, Chengdu 610064, China College of Materials Science and Engineering Key Laboratory of Advanced Materials Processing of Chinese Education Ministry Southwest Jiaotong University Chengdu China School of Basic Medical Sciences West China Center of Medical Sciences Sichuan University Chengdu China

Our previous research results have shown that the Ti-O films with appropriate characteristics possess great potentials for biomaterials application. In this paper, using plasma immersion ion implantation and deposition (PIII-D), titanium oxide thin films are fabricated onto silicon wafer. The antithrombogenesis of films is evaluated in vitro through the platelet adhesion investigation. The biological behavior of human umbilical vein en-dothelial cells (HUVEC) on the film surface is investigated in vitro by endothelial cell (EC) culture. Our results reveal that the crystalline Ti-O films exhibit attractive blood compatibil-ity. The in vitro HUVEC-cultured investigation of Ti-O film surface has justified that the biological behavior of HUVECs on different structure surfaces is significantly different. The adherence, growth and proliferation of HUVECs to the crystalline Ti-O film surface are in order, by forming a perfect single layer, preserving the natural original shape and dis-playing the cobblestone road metal rank, and obviously superior to that on the amorphous Ti-O film surface. According to our study, the crystalline Ti-O film, with proper microstruc-ture, is helpful for seeding ECs and can be used as a functional surface for the adherence and growth of ECs.

关键词： plasma immersion ion implantation and deposition, Ti-O film, antithrombogenesis, endothelial cell.

Risk Analysis on Groundwater Resources Carrying Capacity Based on Blind Number Theory

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Wuhan University Journal of Natural Sciences 2007年第4期12卷 669-676页

作者： ZHANG Ji1,2.YU Sujun31. Key Laboratory of Mountain Hazards and Surface Process,Chinese Academy of Sciences/Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu 610041,Sichuan,China 2. Graduate University of the Chinese Academy of Sciences,Beijing 100049,China 3. School of Environmental Science and Engineering,southwest Jiaotong University,Chengdu 610041,Sichuan,China Key Laboratory of Mountain Hazards and Surface Process Chinese Academy of Sciences Chengdu China Graduate University of the Chinese Academy of Sciences Beijing China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China School of Environmental Science and Engineering Southwest Jiaotong University Chengdu China

Blind numbers of evaluation indices about groundwater resources carrying capacity are defined from the concomitancy of randomness, fuzziness, grey property and unascertainment of groundwater system. Based on fuzzy theory, a comprehensive evaluation model on groundwater resources carrying capacity is constructed with blind information. Then a risk assessment model of surcharge about groundwater resources carrying capacity is established on blind reliability theory. The probable value ＂＊＂ matrix of fuzzy membership degree about carrying capacity corresponding to each judgment level can be obtained with the aid of blind algorithm as well as the subjective reliability ＂×＂ matrix. And then a graph of ＂groundwater carrying capacity v.s. accumulative reliability＂ can be gained Based on the graph, fuzzy membership degree of groundwater resources carrying capacity to each judgment level under different risk probability can be got. Thus, a comparatively reasonable judgment to groundwater resources carrying capacity might be obtained, with comprehensive analysis to the state of society, economy technology and ecology.

关键词： blind number theory groundwater resources carrying capacity evaluation risk analysis

Resonance Rayleigh scattering study of the interaction of bleomycinA_5 with nucleic acids and its analytical application

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Science China Chemistry 2007年第5期50卷 629-637页

作者： LIU JiangTao1,2. LIU ZhongFang1 & LIU ShaoPu1 1 School of Chemistry and Chemical Engineering, southwest University, Chongqing 400715, China 2.Department of Chemistry, Fuling Normal University, Chongqing 408000, China School of Chemistry and Chemical Engineering Southwest University Chongqing China Department of Chemistry Fuling Normal University Chongqing China

The interaction of bleomycinA5 with nucleic acids has been investigated byusing resonance Rayleigh scattering (RRS),molecular absorption and fluorescence *** resultshows that in near pH 2.2.buffer medium and absence of any metal ions,nucleic acids are capable ofbinding with bleomycinA5 (BLMA5) to form complexes which can remarkably enhance the RRS intensityand result in batho-chromic and hyperchromic molecular absorption of nucleic acids and fluorescencequenching of *** RRS spectral characteristics for the binding products of bleomycinA5with various DNA and RNA are similar,and the maximum RRS peaks are at 301 nm for ctDNA and sDNA,370nm for hsDNA,310 nm for RNAtypeVI and RNAtypelll,*** increments of RRS intensity aregreatly different in which DNA enhances greatly and RNA enhances *** this work,the optimumconditions of the interaction and some influencing factors have been *** reactionmechanism and a binding model for the interaction of BLMA5 with the nucleic acids are ***,a highly sensitive,simple and rapid new method for the determination of DNA has *** detection limits (3 sigma) are 5.7 ng/mL for ctDNA,7.4 ng/mL for sDNA and 9.2.ng/mLfor hsDNA,*** method can be applied to determination of trace amounts of DNA.

关键词： bleomycinA5, nucleic acids, resonance Rayleigh scattering, fluorescence quenching, absorption spectrum.

Frequency/time hopping sequence sets with optimal partial Hamming correlation properties

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Science China(Information Sciences) 2012年第10期55卷 2207-2215页

作者： NIU XianHua 1,2.PENG DaiYuan 1 & ZHOU ZhengChun 3 1 The Provincial Key Laboratory of Information Coding and Transmission,Institute of Mobile Communications,southwest Jiaotong University,Chengdu 610031,China 2.The School of Mathematics and Computer Engineering,Xihua University,Chengdu 610039,China 3 The College of Maths,southwest Jiaotong University,Chengdu 610031,China The Provincial Key Laboratory of Information Coding and Transmission Institute of Mobile Communications Southwest Jiaotong University Chengdu China The School of Mathematics and Computer Engineering Xihua University Chengdu China The College of Maths Southwest Jiaotong University Chengdu China

Frequency hopping/time hopping(FH/TH) sequences have found wide applications in various modern FH/TH spread spectrum communications,such as digital cellular mobile communication,short-range wireless communication,personal communication,and multi-user radar,sonar *** order to evaluate the goodness of FH/TH sequences design,the periodic Hamming correlation function is used as an important ***,the length of correlation window is shorter than the period of the chosen FH/TH sequence,so the study of the partial Hamming correlation of FH/TH sequence is particularly *** this paper,a new class of FH/TH sequence sets with good partial Hamming correlation properties is proposed and *** construction of new FH/TH sequence sets is based upon the generalized m-sequence and generalized Gordon-Mills-Welch sequence over a polynomial residue class *** is shown that new FH/TH sequence sets are optimal with respect to the partial Hamming correlation bound.

关键词： frequency hopping/time hopping(FH/TH) sequence partial Hamming correlation optimal FH/TH sequence set