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Using the curve moment and the PSO-SVM method to diagnose downhole conditions of a sucker rod pumping unit

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Petroleum Science 2013年第1期10卷 73-80页

作者： Li Kun gao Xianwen Tian Zhongda qiu Zhixue College of Information Science and Engineering Northeastern University

Downhole working conditions of sucker rod pumping wells are automatically identified on a computer from the analysis of dynamometer cards. In this process, extraction of feature parameters and pattern classification are two key steps. The dynamometer card is firstly divided into four parts which include different production information according to the ＂four point method＂ used in actual oilfield production, and then the moment invariants for pattern recognition are extracted. An improved support vector machine （SVM） method is used for pattern classification whose error penalty parameter C and kernel function parameter g are optimally chosen by the particle swarm optimization （PSO） algorithm. The simulation results show the method proposed in this paper has good classification results.

关键词： Sucker rod pumping unit diagnosis of downhole conditions dynamometer card curvemoment support vector machine particle swarm optimization

Meso-Cenozoic lithospheric thermal structure in the Bohai Bay Basin,eastern North China Craton

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Geoscience Frontiers 2017年第5期8卷 977-987页

作者： Zongxing Li Yinhui Zuo Nansheng qiu Jun gao The Key Laboratory of Shale Oil and Gas Geological Survey Institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology Chengdu 610059 China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China Beijing Key Laboratory of Water Resources and Environment and Engineering Chinese University of Geosciences Beijing 100083 China

The Bohai Bay Basin is a region where part of the North China Craton has been thinned and destroyed. It has experienced two periods of crustal thinning that occurred during the Cretaceous and Paleogene, but investigations of its Mesozoic and Cenozoic lithospheric thermal structure are limited. Therefore, in this study,the distributions of mantle heat flow, crustal heat flow, and Moho temperatures during the Meso-Cenozoic are calculated based on analyses of the thermal history of the Bohai Bay Basin. The results indicate that the ratio of mantle heat flow to surface heat flow peaked during the late stages of the early Cretaceous and during the middle to late Paleogene. The corresponding mantle heat flow was more than 65% of the surface heat flow. Moho temperatures reached three peaks: 900-1100℃ in the late stages of the early Cretaceous;820-900℃ in the middle to late Paleogene; and(in the Linqing Depression, Cangxian Uplift, and Jizhong Depression) 770-810℃ during the early Neogene. These results reveal that the Bohai Bay Basin experienced significant geological change during the Cretaceous, including the transformation of lithospheric thermal structure from "cold mantle and hot crust" before the Cretaceous to "hot mantle and cold crust" after the Cretaceous. The results also indicate that the basin experienced two large-scale rifting ***, this work may provide the thermal parameters for further investigations of the geodynamic evolution of eastern China.

关键词： Bohai Bay Basin Lithospheric thermal structure Mesozoic Moho temperature North China Craton

3D analysis of in-filled trench as passive barriers for ground vibration isolation

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Science China(Physics,Mechanics & Astronomy) 2008年第10期51卷 1573-1585页

作者： gao GuangYun SHI Gang FENG ShiJin qiu Chang Department of Geotechnical Engineering Tongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China Shanghai Pudong Construction Project Management Co.Ltd. Shanghai 201203China

The three-dimensional (3D) problem of the ground vibration isolation by an in-filled trench as a passive barrier is studied theoretically. Integral equations governing Rayleigh wave scattering are derived based on the Green’s solution of Lamb prob-lem. The integral equations are solved accurately and efficiently with an iteration technique. They are used to evaluate the complicated Rayleigh wave field gener-ated by irregular scatterers embedded in an elastic half-space solid. The passive isolation effectiveness of ground vibration by the in-filled trench for screening Rayleigh wave is further studied in detail. Effects of relevant parameters on the effectiveness of vibration isolation are investigated and presented. The results show that a trench filled with stiff backfill material gets a better isolation effect than a soft one, and increasing the depth or width of the in-filled trench also improves its screening effectiveness. The effectiveness and the area of the screened zone are surging with the increase in the length of the in-filled trench.

关键词： Rayleigh wave scattering integral equation in-filled trench passive isolation ground vibration

含贝达喹啉方案治疗耐多药肺结核对患者心电图QT间期的影响

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中国防痨杂志 2020年第7期42卷 687-694页

作者：谢莉高静韬马丽萍张立群孔忠顺吴晓光刘荣梅陈红梅宋艳华李雪莲黄麦玲李强吕子征刘宇红高孟秋首都医科大学附属北京胸科医院结核二科 101149 首都医科大学附属北京胸科医院临床中心办公室 101149

目的探索含贝达喹啉方案对耐多药肺结核患者心电图QT间期(简称"QT")的影响,为贝达喹啉临床安全使用与监测提供依据。方法北京胸科医院在2018年2月至2019年10月依据纳入和排除标准入选符合条件的患者120例,给予含贝达喹啉的耐药结核病治... 详细信息

目的探索含贝达喹啉方案对耐多药肺结核患者心电图QT间期(简称"QT")的影响,为贝达喹啉临床安全使用与监测提供依据。方法北京胸科医院在2018年2月至2019年10月依据纳入和排除标准入选符合条件的患者120例,给予含贝达喹啉的耐药结核病治疗方案,监测并记录患者治疗前基线及治疗后的第2、4、8、12、16、20、24周末及完成贝达喹啉用药疗程后12个月每12周检测1次心电图。按心率校正、采用Fridericia公式计算的QT值(QTcF值)。首先采用t检验、ANOVA检验及秩和检验分析患者基线QTcF值在不同年龄、性别、体质量指数和耐药类型组间的差异性;其次,采用独立样本t检验比较治疗期间不同时点QTcF值与其基线的差异;最后采用多因素logistic回归分析QT延长的影响因素。结果120例患者基线QTcF平均值为(404.90±19.27)ms,使用含贝达喹啉方案治疗过程中23例(19.2%)患者出现QTcF值较基线延长≥60 ms,10例(8.3%)患者同时出现QTcF≥500 ms。患者QTcF平均值随着贝达喹啉使用疗程时间增加逐渐增大,至20周末达峰值,且此前各时点QTcF值均与基线差异具有统计学意义:治疗2周末,QTcF值为(413.51±22.69)ms(t=4.064,P=0.000);治疗4周末,QTcF值为(413.38±17.81)ms(t=4.022,P=0.000);治疗8周末,QTcF值为(414.78±23.71)ms(t=3.796,P=0.000);治疗12周末,QTcF值为(416.23±25.06)ms(t=3.752,P=0.000);治疗16周末,QTcF值为(419.23±29.18)ms(t=4.584,P=0.000);治疗20周末,QTcF值为(425.45±30.84)ms(t=5.865,P=0.000)。完成贝达喹啉疗程后的6个月期间,QTcF平均值在第36周末、48周末分别为(419.10±31.38)ms和(419.60±27.74)ms,与基线比较差异均有统计学意义(治疗36周末,t=3.698,P=0.000;治疗48周末,t=2.790,P=0.007)。QTcF平均值在完成贝达喹啉疗程后的6-12个月期间与基线比较差异无统计学意义[治疗60周末,QTcF值为(409.70±19.60)ms(t=0.759,P=0.453);治疗72周末,QTcF值为(412.77±15.96)ms(t=2.051,P=0.051)]。在上述观察期内所有患者均未出现严重的室性心律失常。多因素分析显示年龄≥45岁的患者出现QT延长的风险是18~<45岁患者的4.473倍(95%CI:1.614~12.401)。结论耐多药肺结核患者应用含贝达喹啉方案治疗所引起的QT延长的比例较高,QTcF值随贝达喹啉使用疗程增加而增大,在完成其使用疗程后的6个月左右即可恢复。多因素分析显示年龄≥45岁的患者出现QT延长的风险高。治疗期间对于QT延长的影响并不会导致严重的室性心律失常。

关键词：结核,肺结核,抗多种药物性药物疗法心电描记术药物毒性贝达喹啉

Effects of vertical seismic acceleration on 3D slope stability

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Earthquake Engineering and Engineering Vibration 2016年第3期15卷 487-494页

作者： Zhang Fei gao Yufeng Wu Yongxin Zhang Ning qiu Yue Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai University

The conventional pseudo-static approach often neglects the effect of the vertical＇ seismic acceleration on the stability of a slope, but some analyses under plane-strain （2D） conditions show a significant effect on the slope stability. The purpose of this study is to investigate the effect of the vertical acceleration on the safety of three-dimensional （3D） slopes. In the strict framework of limit analysis, a 3D kinematically admissible rotational failure mechanism is adopted here for 3D homogeneous slopes in frictional/cohesive soils. A set of stability charts is presented in a wide range of parameters for 3D slopes under combined horizontal and vertical seismic loading conditions. Accounting for the effects of the vertical seismic acceleration, the difference in safety factors for 3D slopes can exceed 10%, which will significantly overestimate the safety of the 3D slopes.

关键词： slope stability seismic effects limit states three-dimensional analysis vertical acceleration

Microstructural Evolution and Toughness in the HAZ of Submerged Arc Welded Low Welding Crack Susceptibility Steel

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Acta Metallurgica Sinica(English Letters) 2013年第1期26卷 49-55页

作者： Chunlin qiu Liangyun LAN Dewen ZHAO Xiuhua gao Linxiu DU State Key Laboratory of Rolling and Automation Northeastern University

Microstructural characteristics of different sub-regions of heat affected zone （HAZ） of low welding crack susceptibility steel weldment were investigated by using optical microscopy and scanning electron microscopy equipped with electron backscattered diffraction system. And the focus was put on the correlation between microstructural characteristics and HAZ toughness of the weldment. The results reveal that the toughness of fusion line zone （FLZ） specimens is much lower than that of fine grained HAZ （FGHAZ） specimens. The coarse inclusions in the weld metal and the large martensite-austenite constituents in the coarse grained HAZ （CGHAZ） have an obvious negative effect on the crack initiation energy of FLZ. Meanwhile, the coarse granular bainite with large effective grain decreases the crack propagation energy seriously. By contrast, fine crystallographic grains in the FGHAZ play a key role in increasing toughness, especially in improving crack propagation energy.

关键词： Steel Heat affected zone (HAZ) Submerged arc welding Effective grain size Toughness Microstructure

Influence of Temperature on the Protectiveness and Morphological Characteristics of Calcareous Deposits Polarized by Galvanostatic Mode

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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 131-139页

作者： Chengjie Li Min Du Jing qiu Jing Zhang Congjie gao The Key Laboratory of Marine Chemistry Theory and Technology Ministry of EducationCollege of Chemistry and Chemical EngineeringOcean University of China

The influence of temperature on calcareous deposits formed under galvanostatic polarization mode was studied. The deposition was monitored by electrochemical impedance spectrum, and a supplementary loop in Nyquist diagram at high frequency was found to be an indicator of deposits precipitation with sufficient protection at above 20 ~C. An exponential increase of protectiveness with temperature was observed, which was quantified by linear polarization resistance technique. Observation by scanning electron microscope and X-ray diffraction analyses demonstrated that the critical temperature of calcium carbonate crystal form transition ranged from 15 to 20 ℃. Calcite formed below 15 ℃, while aragonite precipitated at above 20 ℃.

关键词： Calcareous deposits Temperature Galvanostatic Cathodic protection

Structures of Interaction of Non-selfsimilar Elementary Waves for 2D Scalar Conservation Law with Two Initial Discontinuities

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Acta Mathematicae Applicatae Sinica 2023年第3期39卷 465-490页

作者： Gui-qin qiu gao-wei CAO Xiao-zhou YANG University of Chinese Academy of Sciences Beijing 100049China Wuhan Institute of Physics and Mathematics Innovation Academy for Precision Measurement Science and TechnologyCASWuhan 430071China

In this paper,we investigate the global solution and the structures of interaction between two dimensional non-selfsimilar shock wave and rarefaction wave of general two-dimensional scalar conservation law in which flux functions f(u)and g(u)do not need to be convex,and the initial value contains three constant states which are respectively separated by two general initial *** initial value contains three constant states,the cases of selfsimilar shock wave and rarefaction wave had been studied before,but no results of the cases of neither non-selfsimilar shock wave or non-selfsimilar rarefaction *** the assumption that Condition H which is generalization of one dimensional convex condition,and some weak conditions of initial discontinuity,according to all the kinds of combination of elementary waves respectively staring from two initial discontinuities,we get four cases of wave interactions as S+S,S+R,R+S and R+*** studying these interactions between non-selfsimilar elementary waves,we obtain and prove all structures of non-selfsimilar global solutions for all cases.

关键词： Riemann problem shock wave rarefaction wave wave interaction

Structural dynamics of the yeast Shwachman- Diamond syndrome protein （Sdol） on the ribosome and its implication in the 60S subunit maturation

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Protein & Cell 2016年第3期7卷 187-200页

作者： Chengying Ma Kaige Yan Dan Tan Ningning Li Yixiao Zhang Yi Yuan Zhifei Li meng-qiu Dong Jianlin Lei Ning gao School of Life Sciences Tsinghua University Beijing 100084 China National Institute of Biological Sciences Beijing 102206 China Graduate Program in Chinese Academy of Medical Sciences and Pekinq Union Medical College Beiiin.q 100730 China

The human Shwachman-Diamond syndrome （SDS） is an autosomal recessive disease caused by mutations in a highly conserved ribosome assembly factor SBDS. The functional role of SBDS is to cooperate with another assembly factor, elongation factor l-like （Eft1）, to pro- mote the release of eukaryotic initiation factor 6 （elF6） from the late-stage cytoplasmic 60S precursors. In the present work, we characterized, both biochemically and structurally, the interaction between the 60S subunit and SBDS protein （Sdolp） from yeast. Our data show that Sdolp interacts tightly with the mature 60S subunit in vitro through its domain I and II, and is capable of bridging two 60S subunits to form a stable 2：2 dimer. Structural analysis indicates that Sdolp bind to the ribosomal P-site, in the proximity of uL16 and uL5, and with direct contact to H69 and H38. The dynamic nature of Sdolp on the 60S subunit, together with its strategic binding position, suggests a surveillance role of Sdolp in monitoring the conformational maturation of the ribosomal P-site. Altogether, our data support a con- formational signal-relay cascade during late-stage 60S maturation, involving uL16, Sdolp, and Efllp, which interrogates the functional P-site to control the departure of the anti-association factor elF6.

关键词： ribosome biogenesis SBDS SDS Sdol,cryo-electron microscopy (cryo-EM)