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相邻深基坑开挖相互影响及变形控制研究

市政技术 2024年第6期42卷 81-88,98页

作者：陶连金胡国庆焦伯阳郭飞赵旭张宇北京工业大学城市与工程安全减灾省部共建教育部重点实验室北京100124 北京市政建设集团有限责任公司北京100020 北京建筑大学土木与交通工程学院北京102627

以北京城市副中心站综合交通枢纽项目大铁深基坑和02B区深基坑分期开挖为研究对象,采用有限元软件建立了局部精细化模型,对相邻深基坑开挖的变形特性和影响因素进行了研究,并提出了深基坑变形控制措施。研究结果表明,在相邻深基坑近接... 详细信息

以北京城市副中心站综合交通枢纽项目大铁深基坑和02B区深基坑分期开挖为研究对象,采用有限元软件建立了局部精细化模型,对相邻深基坑开挖的变形特性和影响因素进行了研究,并提出了深基坑变形控制措施。研究结果表明,在相邻深基坑近接施工过程中,先开挖的深基坑呈向后开挖深基坑方向移动的趋势,而坑间土地表沉降变形从凹槽形变为双峰形;根据拟合出的变形曲线斜率,可以将相邻深基坑近接施工影响分区划分为:d<2h为强影响区,2h≤d<4h为次影响区,4h≤d<6h为弱影响区,d≥6h为无影响区;为了确保深基坑群施工的整体稳定性,最优开挖顺序是同步开挖,如需分步开挖应优先开挖支护结构刚度较大、支护力度较强的深基坑;该工程可通过及时在逆作区架设上斜撑来实现变形控制的目的。

关键词：相邻深基坑同步开挖相互影响变形控制措施

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Discussion of Direct Numerical Simulation Method for Supercritical Carbon Dioxide Jet Flow

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Journal of Modern Physics 2013年第10期4卷 1429-1436页

作者： hui Gao guoqing hu College of Petroleum Engineering China University of Petroleum Qingdao China Institute of Mechanics Chinese Academy Science Beijing China

A kind of direct numerical simulation method suitable for supercritical carbon dioxide jet flow has been discussed in this paper. The form of dimensionless nonconservative compressible Navier-Stokes equations in a two-dimensional cartesian coordinate system is derived in detail. High accurate finite difference compact schemes based on non-uniform grid system are introduced to solve the equations. The simulation results of the three vortex pairing phenomenon of plane mixing layer and a compressible axisymmetric jet flow field show that the discussed numerical simulation method is feasible to calculate the supercritical carbon dioxide jet fluid. And it is found that the difficulties of splitting the convective terms in conservation Navier-Stokes equations, which are brought by the supercritical carbon dioxide fluid pressure state equation, can be avoided by solving the nonconservative compressible Navier-Stokes equations.

关键词： Direct Numerical Simulation Supercritical Carbon Dioxide Jet Flow Nonconservative Compressible Navier-Stokes Equations

Global Deaths Associated with Population Aging—1990–2019

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China CDC weekly 2023年第51期5卷 1150-1154,I0001-I0004页

作者： Ruotong Li Xunjie Cheng Yang Yang David CSchwebel Peishan Ning Li Li Zhenzhen Rao Peixia Cheng Min Zhao guoqing hu Guangdong Provincial Center for Disease Control and Prevention Guangzhou CityGuangdong ProvinceChina Department of Epidemiology and Health Statistics Hunan Provincial Key Laboratory of Clinical EpidemiologyXiangya School of Public HealthCentral South UniversityChangsha CityHunan ProvinceChina Department of Geriatric Medicine Xiangya HospitalCentral South UniversityChangsha CityHunan ProvinceChina Department of Statistics Franklin College of Arts and SciencesUniversity of GeorgiaAthensGAUSA Department of Psychology University of Alabama at BirminghamBirminghamALUSA Department of Child Adolescent and Women’s HealthSchool of Public HealthCapital Medical UniversityBeijingChina National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangsha CityHunan ProvinceChina.

Introduction:Published global and countryspecific deaths associated with population aging are based on decomposition methods that have significant ***:A new decomposition method was developed and its performance was compared with two frequently used *** new method was employed to calculate global deaths associated with population aging between 1990 and 2019,using estimates from the Global Burden of Disease Study 2019(GBD 2019).Results:Compared to the two frequently-used existing methods,the new decomposition method generated results that are more consistent with logical *** the new method,the number of global deaths associated with population aging between 1990 and 2019 was 23.3 *** middleincome countries accounted for 43%of global deaths related to population *** most deaths associated with population aging occurred from three types of disease:ischemic heart disease(5.0 million),stroke(3.8 million),and chronic obstructive pulmonary disease(2.2 million).China,India,Japan,the United States of America,and Brazil had the largest number of deaths related to population *** related to population aging was completely or partially counteracted by the reduction in mortality in 195 of the 200 countries and territories experiencing population aging(97.5%).Conclusions:The new decomposition method achieves more justifiable results associated with population aging than existing ***,population aging was associated with a substantial increase of deaths between 1990 and 2019,but it was totally or partially offset by the reduction in mortality in 97.5%of countries and territories.

关键词： Population income totally

Theory Analysis of the Handover Challenge in Express Train Access Networks （ETAN）

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China Communications 2014年第7期11卷 92-98页

作者： hu guoqing huANG Anpeng HE Ruisi AI Bo CHEN Zhangyuan State Key Lab of Advanced Optical Communication Systems and Networks Peking University Beijing 100871 P. R. China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 E R. China

To handle the handover challenge in Express Train Access Networks(ETAN).mobility fading effects in high speed railway environments should be addressed *** on the investigation of fading effects in this paper,we obtain two theoretical bounds:HOTiming upper bound and HO-Margin lower bound,which are helpful guidelines to study the handover challenge today and in the ***,we apply them to analyze performance of conventional handover technologies and our proposal in *** follow-up theory analyses and simulation experiment results demonstrate that the proposed handover solution can minimize handover time up to 4ms(which is the fastest one so far),and reduce HO-Margin to 0.16 dB at a train speed of 350km/h.

关键词： express train access network handover (HO) high speed railways HO-timing upper bound HO-margin lower bound

Research on cell cycle retardation, apoptosis and the expression of antioncogene p57^(Kip2) by radioactive rays in nasopharyngeal carcinoma cell line in vitro

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The Chinese-German Journal of Clinical Oncology 2007年第3期6卷 274-277页

作者： Yinping Sun guoqing hu Department of Oncology Zibo Center Hospital Zibo 255036 China Department of Oncology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

Objective: To study cell cycle retardation, apoptosis and the expression of antioncogene p57kip2 by radioactive rays in nasopharyngeal carcinoma cells. Methods: Cell cycle retardation, apoptosis and cell survival rate induced by radioac- tive rays were tested by the methods of flow cytometry and MTT method. The expression of antioncogene p57kip2 was detected by immunohistochemistry and Western blot. Results: After irradiation, G1 phase had no obvious retardation, S phase showed transient delay. There was a positive correlation between irradiation dosage and retardation strength in G2/M phase (P < 0.01). Peak value appeared at 24 h after 12 Gy irradiation, then decreased. There was a positive correlation between apop- tosis incidence and irradiation dosage or after-irradiation time extention (P < 0.01). There was a negative correlation between cell survival rate and irradiation dosage or apoptosis incidence (P < 0.01). The expression of p57kip2 protein was up-regulated along with the prolongation of time and dosage after irradiation (P < 0.01). Conclusion: G2/M phase arrest, apoptosis and the up-regulation of the expression of p57kip2 protein all can reflect predict the radiosensitivity of nasopharyngeal carcinoma cells.

关键词： nasopharyngeal carcinoma cell G2/M arrest apoptosis p57^kip2 protein radiosensitivity

Recursion Least Square Method to Study the Fault Diagnosis and Its Model of Hydraulic Equipment

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International Journal of Plant Engineering and Management 1999年第1期4卷 383-390页

作者： hu guoqing Luo Renfei(Department of Mechanical and Electrical Engineering,Xiamen University, 361005, Xiamen, Fujian, P.R.ChinaEmail: gqhu@***)

In this paper establishing model of the fault diagnosis of hydraulic equipment isdescribed in details. It also studies the advantage of the recursion least square method. When theLSM is used in compuring the fault of hydraulic equipment, not only does it save the computerCPU-time and memory, but it also has a high computation speed and,makes it easy to identifythe estimation parameters.

关键词： medel fault hydraulic equipment recursion least square method.

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基于图论的产品实例检索结构相似度分析

农业机械学报 2011年第8期42卷 184-188,206页

作者：胡伟胡国清魏昕谢小柱华南理工大学机械与汽车工程学院广州510641 广东工业大学机电工程学院广州510006

针对机电产品各子系统之间的复杂作用关系,提出了基于有向模糊图的产品系统结构相似度计算模型,以实现产品概念设计的实例检索。扩展定义了有向模糊图概念,建立机电产品系统有向图模型,利用积和式矩阵对有向图模型进行描述;通过积和式... 详细信息

针对机电产品各子系统之间的复杂作用关系,提出了基于有向模糊图的产品系统结构相似度计算模型,以实现产品概念设计的实例检索。扩展定义了有向模糊图概念,建立机电产品系统有向图模型,利用积和式矩阵对有向图模型进行描述;通过积和式函数多项式对产品系统进行结构分析,将主观权重和客观权重组合计算产品系统有向图结构相似度。以SF2005型加速度传感器的实例检索为例证明了该结构相似度计算模型的可行性。

关键词：产品系统实例检索结构相似度有向模糊图

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微流控器件中的多相流动

力学进展 2015年第1期45卷 55-110页

作者：陈晓东胡国庆中国科学院力学研究所非线性力学国家重点实验室北京100190

微流控技术及微流控器件是近年来发展迅速的多学科交叉研究领域.相比于传统方法,微流控技术能够实现对微量多相流体的精准操控,可应用于化学分析、先进材料合成、蛋白质结晶、单细胞培育及检测、信息处理等领域.该文回顾微流控器件中的... 详细信息

微流控技术及微流控器件是近年来发展迅速的多学科交叉研究领域.相比于传统方法,微流控技术能够实现对微量多相流体的精准操控,可应用于化学分析、先进材料合成、蛋白质结晶、单细胞培育及检测、信息处理等领域.该文回顾微流控器件中的多相流动现象,概述其所涉及的流体力学机理,阐述实现多相微流控的各种方法,并分析多相微流控技术的应用现状及面临的挑战,最后总结针对多相微流动问题的数值模拟方法和实验测量技术,展望多相微流控器件的研究方向及应用前景.

关键词：微尺度流动多相流动液滴微流控器件

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代数应力模型在液压集成块流道中的应用

上海交通大学学报 1994年第4期28卷 130-137页

作者：胡国清上海交通大学机械工程系上海

本文根据Ｎａｉｖｅｒ－Ｓｔｏｋｅｓ方程推导出适合于液压阀流道计算的代数应力模型．通过对液压集成块流道的数值模拟结果与实验结果比较，吻合较好，因此它是研究液压阀流道的一种很有效的计算模型．

关键词：代数应力模型液压集成块液压阀