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Health diagnosis of ultrahigh arch dam performance using heterogeneous spatial panel vector model

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Water Science and Engineering 2024年第2期17卷 177-186页

作者： Er-feng Zhao Xin Li chong-shi gu The National Key Laboratory of Water Disaster Prevention Hohai UniversityNanjing 210098China NationalEngineering Research Centerof Water Resources Eficient Utilization and Engineering Safety Hohai UniversityNanjing 20098China

Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in *** control is essential to long-term operation of these *** study employed the flexibility coefficient and plastic complementary energy norm to assess the structural safety of arch dams.A comprehensive analysis was conducted,focusing on differences among conventional methods in characterizing the structural behavior of the Xiaowan arch dam in ***,the spatiotemporal characteristics of the measured performance of the Xiaowan dam were explored,including periodicity,convergence,and time-effect *** findings revealed the governing mechanism of main ***,a heterogeneous spatial panel vector model was developed,considering both common factors and specific factors affecting the safety and performance of arch *** model aims to comprehensively illustrate spatial heterogeneity between the entire structure and local regions,introducing a specific effect quantity to characterize local deformation ***,the proposed model was applied to the Xiaowan arch dam,accurately quantifying the spatiotemporal heterogeneity of dam ***,the spatiotemporal distri-bution characteristics of environmental load effects on different parts of the dam were reasonably *** of the model prediction enhances its credibility,leading to the formulation of health diagnosis criteria for future long-term operation of the Xiaowan *** findings not only enhance the predictive ability and timely control of ultrahigh arch dams'performance but also provide a crucial basis for assessing the effectiveness of engineering treatment measures.

关键词： Ultrahigh arch dam Structural performance Deformation behavior Diagnosis criterion Panel data model

Monitoring models for base flow effect and daily variation of dam seepage elements considering time lag effect

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Water Science and Engineering 2018年第4期11卷 344-354页

作者： Shao-wei Wang Ying-li Xu chong-shi gu Teng-fei Bao School of Environmental and Safety Engineering Changzhou University State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University

Affected by external environmental factors and evolution of dam performance, dam seepage behavior shows nonlinear time-varying characteristics. In this study, to predict and evaluate the long-term development trend and short-term fluctuation of the dam seepage behavior, two monitoring models were developed, one for the base flow effect and one for daily variation of dam seepage elements. In the first model, to avoid the influence of the time lag effect on the evaluation of seepage variation with the time effect component of seepage elements, the base values of the seepage element and the reservoir water level were extracted using the wavelet multi-resolution analysis method, and the time effect component was separated by the established base flow effect monitoring model. For the development of the daily variation monitoring model for dam seepage elements, all the previous factors, of which the measured time series prior to the dam seepage element monitoring time may have certain influence on the monitored results, were considered. Those factors that were positively correlated with the analyzed seepage element were initially considered to be the support vector machine(SVM) model input factors, and then the SVM kernel function-based sensitivity analysis was performed to optimize the input factor set and establish the optimized daily variation SVM model. The efficiency and rationality of the two models were verified by case studies of the water level of two piezometric tubes buried under the slope of a concrete gravity *** analysis of the optimized SVM model shows that the influences of the daily variation of the upstream reservoir water level and rainfall on the daily variation of piezometric tube water level are processes subject to normal distribution.

关键词： Dam seepage monitoring model Time lag effect Support vector machine(SVM) Sensitivity analysis Base flow Daily variation Piezometric tube water level

Visualization of Wormlike Micelle Fluid Flow in a Mixing Tank

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Transactions of Tianjin University 2018年第4期24卷 308-317页

作者： Hongyuan Wei Jieliang Lu chong gu Kate Xu Boonho Ng Leping Dang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Procter&Gamble Technology(Beijing)Co. LtdBeijing 101312China

In this study,particle image velocimetry was applied to investigate flow fields of wormlike micelle(WLM) fluids in a mixing tank equipped with a four-blade,down-pumping,pitched blade turbine. First,the rheology of WLM fluids was investigated,and the Carreau model was utilized to describe their apparent viscosity. Then,the effects of the rotation speeds and rheological properties on the flow fields were studied using different WLM fluids at different rotation speeds. The results revealed that with increasing Reynolds number,the discharge angle decreases and the carven size increases. Furthermore,elastic effects of WLM fluids lead to a more curved flow and a smaller carven.

关键词： Wormlike micelle PIV Mixing Flow fi eld

The present-day kinematics of the Tianshan orogenic belt constrained by GPS velocities

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Geodesy and Geodynamics 2024年第6期15卷 543-553页

作者： chong gu Bin Zhao Tianchen Sheng Wei Wang Dongzhen Wang Daiqin Liu Jie Li Pinji Lv Xuejun Qiao Key Laboratory of Earthquake Geodesy Institute of SeismologyChina Earthquake AdministrationWuhan 430071China Qinghai Provincial Basic Surveying and Mapping Institute Xining 810001China Urumqi Institute of Central Asia Earthquake China Earthquake AdministrationUrumqi 830011China Hubei Earthquake Administration Wuhan 430071China

Since the late Cenozoic,the reactivated Tianshan orogenic belt has accommodated crustal shortening exceeding 200 km,primarily due to the far-field effects of the India-Eurasia plate ***,the details of the strain partitioning in the Tianshan Mountain range remain *** interpret a new compilation of GPS velocities covering the whole Tianshan range with a classic elastic block *** to previous studies with a block modeling approach,the Tianshan orogenic belt is further subdivided into several blocks based on geological fault traces and a clustering analysis *** addition to obvious crustal shortening on the bounding thrust faults of the Tianshan,our inverted fault slip rates also reveal that faults within the Tianshan orogenic belt,such as the Nalati Fault and the southern margin of the Issyk-Kul Lake Fault,which plays a crucial role in accommodating the tectonic crustal *** the 72°E-78°E region,the internal shortening rate within the mountain is approximately 5-7 mm/*** crustal shortening,strike-slip motion occurs on faults in the interior of the mountain range as well as in the foreland fold-and-thrust belts,especially in the southern margin of the *** findings suggest that the crustal deformation in the Tianshan Mountain range is more complex than previously thought,and the oblique convergence between the Tarim Basin and the Tianshan probably results in both strike-slip and thrust motion.

关键词： Tianshan orogenic belt GPS Elastic block model Crustal deformation

Predictors of contrast-induced acute kidney injury in patients with coronary artery disease receiving contrast agents twice within 30 days

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Military Medical Research 2020年第3期7卷 350-358页

作者： chong-Huai gu Xiao-Zeng Wang Ya-Ling Han Quan-Min Jing Li-Li Ren Yan Zhang Jun-Yin Peng Xin Zhao Cardiovascular Research Institute and Department of Cardiology General Hospital of Shenyang Military RegionShenyang 110840China Department of Cardiovascular Anqing Municipal HospitalAnqing 246000AnhuiChina

Background:None of study mentioned about contrast-induced acute kidney injury(CI-AKI)in people who have received contrast agents twice within in a short period of *** study is trying to identify the ***:We enrolled 607 patients between Oct.2010 and Jul.2015 who received contrast agents twice within 30 days in the Department of Cardiology of the General Hospital of Shenyang Military *** primary outcome was CI-AKI within 72 h after contrast agent *** were divided into groups A(n=559)and group B(n=48)according to whether CI-AKI occurred after the second ***:Patients in group B(CI-AKI occurred after the second agent)had a more rapid heart rate and more usage of diuretics and *** group B,CI-AKI occurred more frequently after the first *** logistic regression showed that diuretic(P=0.006)and intra-aortic balloon pump(IABP)usage(P=0.012)were independent predictors of CI-AKI after the first ***-converting enzyme inhibitor/AngiotensinⅡreceptor antagonist(ACEI/ARB)usage(P=0.039),IABP usage(P=0.040)and CI-AKI occurring after administration of the first agent(P=0.015)were independent predictors of CI-AKI after the ***,dividing the patients into tertiles of the time interval between the two agents showed that CI-AKI occurred more frequently when the second agent was administered within 1–3 days after the first exposure than within 4–6 days(12.4%vs.5.0%,P=0.008)or≥7 days(12.4%vs.6.4%,P=0.039).Conclusions:Diuretic and IABP usage are independent predictors of CI-AKI following exposure to a first contrast *** major predictors of CI-AKI after exposure to a second agent are time since the first contrast exposure,ACEI/ARB usage,and IABP *** importantly,a three-day interval between the two agents is associated with a higher incidence of CI-AKI following the second administration.

关键词： Predictors Contrast-induced acute kidney injury Coronary artery disease

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基于改进目标函数的多参数优化反演方法

水利学报 2008年第8期39卷 969-975页

作者：谷艳昌顾冲时河海大学水利水电工程学院

优化反演方法在工程反演计算过程中,需要进行反复的正演计算,导致效率非常低。本文提出了目标函数的改进形式,并完成了改进形式的计算求解推导,大大减少了优化反演算法的正演算次数,提高了计算效率。在此基础上,与传统遗传算法相结合,... 详细信息

优化反演方法在工程反演计算过程中,需要进行反复的正演计算,导致效率非常低。本文提出了目标函数的改进形式,并完成了改进形式的计算求解推导,大大减少了优化反演算法的正演算次数,提高了计算效率。在此基础上,与传统遗传算法相结合,开发了线弹性多参数优化反演计算程序。以小湾水电站为工程实例,反演了施工期坝基分区综合变形模量。结果表明,所提出的改进方法克服了传统遗传算法需要大量正演计算的固有瓶颈,极大地提高了反演计算效率,且计算精度可靠。改进后的目标函数同样可以与其它优化算法相结合开发相应的改进优化反演程序。

关键词：改进目标函数多参数优化反演遗传算法小湾水电站

RESEARCH ON SEEPAGE MONITORING MODEL OF EARTH-ROCK DAM

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Journal of Hydrodynamics 2003年第1期15卷 78-83页

作者： gu chong shi, Zhang Qian fei College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

With the characteristics of seepage flow in earth-rock dams, a seepagemonitoring model was established based on the finite element method for 3-D seepage flow togetherwith observed data and was used to analyze and monitor the seepage of dams. In order to find out andmonitor the seepage status of the whole dam, the separation of seepage a-mount for dam body, damfoundation and side banks was made theoretically by using the model. Practical example shows thatthe accuracy of computed results is satisfactory and the separation results are more objective.

关键词： earth-rock dam seepage monitoring model

Efficacy and safety of fondaparinux versus enoxaparin in patients undergoing percutaneous coronary intervention treated with the glycoprotein IIb/IIIa inhibitor tirofiban

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Journal of Medical Colleges of PLA(China) 2016年第2期31卷 73-79页

作者： Xin Zhao Xiao-Xu Yang Su-Zhen Ji Xiao-Zeng Wang Li Wang chong-Huai gu Li-Li Ren Ya-Ling Han Cardiovascular Research Institute Department of Cardiology Shenyang Northern Hospital Department of Cardiology Second Affiliated Hospital of Shenyang Medical College

Background: In worldwide, the mortality rate of acute myocardial infarction(AMI) raises year by year. Although the applications of percutaneous coronary intervention(PCI) and anticoagulants effectively reduce the mortality of patients with acute coronary syndrome(ACS), but also increase the incidence of bleeding. Therefore, drugs with stable anticoagulant effects are urgently ***: We enrolled 894 patients with acute coronary syndrome who underwent percutaneous coronary intervention in Shenyang Northern Hospital from February 2010 to May 2012; 430 patients were included in the fondaparinux group(2.5mg/d), and 464 were included in the enoxaparin group(1mg/kg twice daily). Fondaparinux and enoxaparin were applied for 3–7 days. All patients were treated with tirofiban [10μg/kg for 3min initially and 0.15μg/(kg·min) for 1 to 3 days thereafter]. The primary efficacy endpoint was the incidence of a major adverse cerebrovascular or cardiovascular event. The primary safety endpoint was bleeding within 30 days and 1 year after percutaneous coronary ***: One-year data were available for 422 patients in the fondaparinux group and for 453 in the enoxaparin group. The incidence of a major adverse cerebrovascular or cardiovascular event(10.9% vs 12.6%, P=0.433) and cardiac mortality(0.5% vs 1.5%, P=0.116) were generally lower in the fondaparinux group than in the enoxaparin group, although the differences were not significant. Compared with the enoxaparin group, the fondaparinux group had a significantly decreased rate of bleeding at 30 days(0.9% vs 2.9%, P=0.040) and 1 year(2.4% vs 5.5%, P=0.018). In addition, the rate of major bleeding events was lower in the fondaparinux group, but this difference was not significant(0.2% vs 0.9%, 0.2% vs 1.1%).Conclusion: In tirofiban-treated patients with acute coronary syndrome undergoing percutaneous coronary intervention, fondaparinux presented similar efficacy for ischemia events as enoxaparin. However, fonda

关键词： Acute coronary syndrome Fondaparinux Enoxaparin Anticoagulation Tirofiban

联合运用改进的极限平衡法和动态规划法分析边坡稳定性

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水利学报 2007年第10期38卷 1272-1277页

作者：吴海真顾冲时河海大学水利水电工程学院

为了解决边坡关键滑动面全局优化处理问题,将动态规划理论引入基于有限元的改进极限平衡法。与工程上被广泛认可的一般极限平衡法比较表明,本文提出的方法可以获得更好的近似解甚至是整体最优解,关键滑动面更符合工程实际,有效地克服了... 详细信息

为了解决边坡关键滑动面全局优化处理问题,将动态规划理论引入基于有限元的改进极限平衡法。与工程上被广泛认可的一般极限平衡法比较表明,本文提出的方法可以获得更好的近似解甚至是整体最优解,关键滑动面更符合工程实际,有效地克服了传统边坡稳定分析方法的不足;与目前国内外同类方法相比具有明显的优越性,丰富了边坡稳定分析和确定关键滑动面的方法和理论。

关键词：边坡稳定有限元改进的极限平衡法关键滑动面动态规划