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Journal of Rock Mechanics and Geotechnical engineering 2024年第5期16卷 1637-1648页

作者： Guiyun Gao Chenghu Wang ke Gao National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing100085China Beijing engineering Research Center of Earthquake Observation Beijing100085China key Laboratory of Compound and Chained Natural Hazards Dynamics Ministry of Emergency Management of ChinaBeijing100085China department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen518055China

The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor ***,the stress tensor determination based on the HTPF method requires at least six tests or a minimum of 14-15 tests(under different conditions)for reliable *** this study,we modified the HTPF method by considering the shear stress on each pre-existing fracture,which increased the number of equations for the stress tensor determination and decreased the number of tests *** shear stresses were attributed to different fractures by random sampling;therefore,the stress tensors were obtained by searching for the optimal solution using the least squares criterion based on the Monte Carlo ***,we constrained the stress tensor based on the tensile strength criterion,compressive strength criterion,and vertical stress *** inverted stress tensors were presented and analyzed based on the tensorial nature of the stress using the Euclidean mean stress *** stress-measurement campaigns in Weifang(Shandong Province,China)and Mercantour road tunnel(France)were implemented to highlight the validity and efficiency of the modified HTPF(M-HTPF)*** results showed that the M-HTPF method can be applied for stress tensor inversion using only three to four tests on pre-existing fractures,neglecting the stress *** inversion results were confined to relatively small distribution dispersions and were significantly reliable and stable due to the shear stresses on the fractures and the stress constraints *** M-HTPF method is highly feasible and efficient for complete stress tensor determination in a single borehole.

关键词： Stress tensor hydraulic tests on pre-existing fractures Mean stress Stress constraint hydraulic fracturing

Simulation and Analysis of a Gravity Cyh'nder's Stability in Short-Crested Sea

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China Ocean engineering 1992年第1期7卷 37-48页

作者： Yu ke and Su Weidong Postgraduate, River and Harbour department, Nanjing hydraulic ResearchInstitute, Nanjing Engineer, River and Harbour department, Nanjing hydraulic Research Institute, Nanjing

Generally, the reliability of ami -sliding and anti-overturning stability of an isolated gravity cylinder in a certain working period can be evaluated only when the statistical properties of short term stability are given first. The authors used numerical method to simulate the stability state function of a cylinder in short-crested sea, and further to get the probabilitical characteristics of the structure's stability by time domain analysis. The external loads appeared in the state functions include horizontal wave force, lift force and the respective moments, and the loads are correlated by co- spectrum. The numerical method presented in this paper can be used not only to solve short term reliability problem directly, but to calculate and analyse the long term reliability problem as well. For circular cylinders, an example of simulation and analysis is displayed in this paper.

关键词： numerical method structure stability wave force probability gravity cylinder

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基于模式识别的结构健康监测异常数据诊断

建筑结构学报 2024年第3期45卷 113-122页

作者：高珂翁顺陈志丹朱宏平夏勇华中科技大学土木与水利学院湖北武汉430074 华中科技大学控制结构湖北省重点实验室湖北武汉430074 国家数字建造技术创新中心湖北武汉430074 香港理工大学土木与环境工程系中国香港999077

实际结构监测中不可避免出现异常数据,干扰结构的安全评估并引起误判。针对实际监测中多类型异常数据检测效率低和检测结果不准确的问题,提出一种基于特征提取和模式识别神经网络(PRNN)的多类型异常数据识别方法。针对不同类型异常数据... 详细信息

实际结构监测中不可避免出现异常数据,干扰结构的安全评估并引起误判。针对实际监测中多类型异常数据检测效率低和检测结果不准确的问题,提出一种基于特征提取和模式识别神经网络(PRNN)的多类型异常数据识别方法。针对不同类型异常数据的特点建立特征指标集合,通过特征提取将冗长原始样本转化为简短特征向量,显著提高了数据处理和异常检测的效率;进一步引入极坐标化AUCs曲线对多种异常的识别效果进行精确描述,提高了特征指标选取和网络参数调节的优化效率。建立武汉长江航运中心(335 m)健康监测系统,采用该超高层建筑的监测数据对所提方法的精度和效率予以验征。结果表明,基于特征提取和PRNN的多类型异常数据识别方法对6种数据异常的识别准确率达到99.7%,且运算时长仅为深度学习方法的数十分之一。

关键词：结构健康监测异常数据检测模式识别神经网络特征提取极坐标化AUCs曲线

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非线性剪胀模型土石坝变形计算适用性评价

水力发电学报 2024年第2期43卷 99-109页

作者：王克汤洪洁王睿张建民清华大学水圈科学与水利工程全国重点实验室北京100084 清华大学水利水电工程系北京100084 清华大学水利部水圈科学重点实验室北京100084 水利部水利水电规划设计总院北京100120

以有限元方法为代表的高土石坝变形数值模拟的准确性极大依赖于本构模型对坝料应力应变关系描述的准确性。本文在邓肯-张EB模型基础上,建立了用于分析坝体变形的考虑剪胀的实用性非线性模型(EB-Dilatancy模型,简称为EBD模型)。基于阿尔... 详细信息

以有限元方法为代表的高土石坝变形数值模拟的准确性极大依赖于本构模型对坝料应力应变关系描述的准确性。本文在邓肯-张EB模型基础上,建立了用于分析坝体变形的考虑剪胀的实用性非线性模型(EB-Dilatancy模型,简称为EBD模型)。基于阿尔塔什面板砂砾石坝的大坝变形监测数据,设计了3个反演方案,获得最优的EB模型和EBD模型参数。采用最优参数模拟常规三轴试验,并与实际物理试验进行比较。结果表明:在坝体变形方面,传统的EB模型难以同时准确模拟堆石坝的沉降和水平变形分布,而EBD模型则能够在维持沉降分布模拟精度的基础上提高水平变形的计算精度;EB模型无法实现在合理模拟大坝变形的前提下有效模拟材料单元应力-应变响应,相比之下EBD模型可以同时实现大坝变形和材料单元力学行为的良好模拟。

关键词：高土石坝本构模型剪胀变形监测反演分析三轴试验

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液压泵和滚动轴承多种样本量的改进多任务故障诊断

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振动与冲击 2024年第4期43卷 270-278页

作者：郑直曾魁魁何玉灵李克王志军华北理工大学机械工程学院河北唐山063210 华北电力大学电机健康维护与故障预防河北省重点实验室河北保定071000

基于充足样本的多个设备元件导致多任务学习网络规模庞大,轻微和严重的跨元件零样本问题难度大。在多种样本量(充足样本和零样本)下,针对基于充足故障样本的多元件诊断网络规模过于庞大问题,引入MicroNet方法对多任务学习网络进行轻量... 详细信息

基于充足样本的多个设备元件导致多任务学习网络规模庞大,轻微和严重的跨元件零样本问题难度大。在多种样本量(充足样本和零样本)下,针对基于充足故障样本的多元件诊断网络规模过于庞大问题,引入MicroNet方法对多任务学习网络进行轻量化处理,然后利用热重启余弦退火算法优化上述网络,提出一种多任务轻量化学习网络模型,改善多任务学习网络的准确率和效率。针对更高难度的跨元件零样本问题,引入元学习方法进一步改进上述MT-MN-CA,进而提出一种改进多任务轻量化学习网络模型,解决轻微和严重的跨元件零样本问题。通过实测液压泵和滚动轴承故障验证所提两个网络模型的有效性和优越性,试验结果表明所提网络具有很高的实时性和准确率。

关键词：多任务学习轻量化元学习零样本故障诊断

Study on Hydrodynamic Coefficients of Double Submerged Inclined Plates

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China Ocean engineering 2018年第1期32卷 85-89页

作者： WANG ke ZHANG Zhi-qiang State key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of Technology School of hydraulic engineering Faculty of Infrastructure Engineering Dalian University of Technology

Added mass and damping coefficients are very important in hydrodynamic analysis of naval structures. In this paper,a double submerged inclined plates with ‘/\’ configuration is firstly considered. By use of the boundary element method(BEM) based on Green function with the wave term, the radiation problem of this special type structure is investigated. The added mass and damping coefficients due to different plate lengths and inclined angles are obtained. The results show that: the added mass and damping coefficients for sway are the largest. Heave is the most sensitive mode to inclined angles. The wave frequencies of the maximal added mass and damping coefficients for sway and roll are the same.

关键词： double submerged inclined plates boundary element method(BEM) added mass and damping coefficients GMRES method

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某L河固床坝坝后消能设施加固设计研究

西藏科技 2024年第8期46卷 67-71页

作者：勾建朋傅柯西安黑河供水有限责任公司黑河输水渠道管理分公司西安710061

文章以某L河固床坝坝后消能设施加固设计研究保障城市平稳供水为背景,在分析工程地质、施工导流等因素的基础上,通过水力学计算分析,提出了最佳设计方案,最终取得良好的效果,不仅对同类型固床坝坝后消能设施加固设计可以起到参考借鉴,... 详细信息

文章以某L河固床坝坝后消能设施加固设计研究保障城市平稳供水为背景,在分析工程地质、施工导流等因素的基础上,通过水力学计算分析,提出了最佳设计方案,最终取得良好的效果,不仅对同类型固床坝坝后消能设施加固设计可以起到参考借鉴,也对于工程管理部门日常技术管理工作提供参考。

关键词：输水固床坝消能加固设计研究

Numerical modeling of gravitational erosion in rill systems

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International Journal of Sediment Research 2011年第4期26卷 403-415页

作者： Peng HAN,Jin-Ren NI,ke-Bin HOU,Chi-Yuan MIAO,and Tian-Hong LI 1 Assoc.Prof,2 Prof.,3 Master,4 Dr.,5 Assoc.Prof.,department of Environmental engineering,Peking University,Beijing 100871,P.R.China,The key Laboratory of Water and Sediment Sciences,Ministry of Education,P.R.China, Assoc. Prof. Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China Prof. Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China Master Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China Dr. Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China

A self-organizing model was developed for simulating rill erosion process on slopes with particular attention to the role of gravitational *** a complete simulation circle,processes such as precipitation,infiltration,runoff,scouring,gravitational erosion and elevation variation were fully *** time(or runoff time) was regarded as iteration benchmark in the *** specify the contribution of gravitational erosion to the process of rill formation and development,a gravitational erosion module was inserted into the *** erosion in rill development was regarded as a Gaussian random process.A model was calibrated by our experimental data,and further validated satisfactorily with 22 runs of experimental results from different investigators. Systematic comparison was made between sediment yields with and without consideration of gravitational erosion *** was demonstrated that the model could reasonably simulate the rill erosion process under a variety of slope gradients,rainfall intensities and soil conditions upon the gravitational erosion being ***,the role of gravitational erosion on sediment yields in rill systems varies significantly under different conditions,although it is of the utmost importance in steeper *** process of gravitational erosion in rill development was studied by a newly-defined parameter a>,which is defined as the volume ratio of gravitational erosion over hydraulic-related *** gravitational contribution to the total erosion could be over 50%for the rill systems with higher rainfall intensity and steeper slopes.

关键词： Self-organizing model Rill erosion Gravitational erosion Gaussian noise

DYNAMIC MODEL AND SIMULATION OF A NOVEL ELECTRO-hydraulic FULLY VARIABLE VALVE SYSTEM FOR FOUR-STROke AUTOMOTIVE ENGINES

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Chinese Journal of Mechanical engineering 2007年第5期20卷 80-86页

作者： WONG Pak-kin TAM Lap-mou LI ke department of Electromechanical engineering Faculty of Science and Technology University of Macao Macao China

In modem four-stroke engine technology, variable valve timing and lift control offers potential benefits for making a high-performance engine. A novel electro-hydraulic fully variable valve train for four-stroke automotive engines is introduced. The construction of the nonlinear mathematic model of the valve train system and its dynamic analysis are also presented. Experimental and simulation results show that the novel electro-hydraulic valve train can achieve fully variable valve timing and lift control. Consequently the engine performance on different loads and speeds will be significantly increased. The technology also permits the elimination of the traditional throttle valve in the gasoline engines and increases engine design flexibility.

关键词： Fully variable engine valve train Dynamic model Simulation