检索结果-南通市图书馆

Simplified Calculation Methods for All-Vertical-Piled Wharf in Offshore Deep Water

China Ocean Engineering 2017年第2期31卷 182-191页

作者： wang yuan-zhan HE Lin-lin State Key Laboratory for Simulation & Safety of Hydraulic Engineering Tianjin Key Laboratory of Harbor & Ocean EngineeringTianjin University College of River and Ocean Engineering Key Laboratory of Regulation Technology for Inland Waterway in Transportation IndustryKey Laboratory of Hydraulic and Waterway Engineering of Ministry of EducationChongqing Jiaotong University

All-vertical-piled wharf is a kind of high-piled wharf, but it is extremely different from the traditional ones in some aspects, such as the structural property, bearing characteristics, failure mechanism, and static or dynamic calculation methods. In this paper, the finite element method （FEM） and theoretical analysis method are combined to analyze the structural property, bearing behavior and failure mode of the all-vertical-piled wharf in offshore deep water, and to establish simplified calculation methods determining the horizontal static ultimate bearing capacity and the dynamic response for the all-vertical-piled wharf. Firstly, the bearing capability and failure mechanism for all-vertical-piled wharf are studied by use of FEM, and the failure criterion is put forward for all-vertical-piled wharf based on the ＇plastic hinge＇. According to the failure criterion and P-Y curve method, the simplified calculation method of the horizontal static ultimate bearing capacity for all-vertical-piled wharf is proposed, and it is verified that the simplified method is reasonable by comparison with the FEM. Secondly, the displacement dynamic magnification factor for the all-vertical-piled wharf under wave cyclic loads and ship impact loads is calculated by the FEM and the theory formula based on the single degree of freedom （SDOF） system. The results obtained by the two methods are in good agreement with each other, and the simplified calculation method of the displacement dynamic magnification factor for all-vertical-piled wharf under dynamic loads is proposed. Then the simplified calculation method determining the dynamic response for the all-vertical-piled wharf is proposed in combination with P-Y curve method. That is, the dynamic response of the structure can be obtained through the static calculation results of P-Y curve method multiplied by the displacement dynamic magnification factor. The feasibility of the simplified dynamic response method is verified by compariso

关键词： all-vertical-piled wharf failure criterion plastic hinge dynamic amplification coefficient simplified calculation methods

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Practical method and application study for predicting cyclic accumulative deformations of the saturated soft clay

引用

Journal of Mountain Science 2017年第11期14卷 2348-2358页

作者： HE Lin-lin wang yuan-zhan LI Shu-zhao wang Zhao-yang Key Laboratory of Hydraulic and Waterway Engineering of Ministry of Education Key Laboratory of regulation technology for inland waterway in transportation industry Chongqing Jiaotong University State Key Laboratory for Simulation & Safety of Hydraulic Engineering Tianjin Key Laboratory of Harbor & Ocean Engineering Tianjin University CNOOC Research Institute

The distribution of saturated soft clay is greatly wide in China. The current main measures adopted to deal with soft soil foundations may lead to environmental pollution, even some engineering accidents may happen on soft soil foundations. In order to solve engineering problems of saturated soft soil foundations well, researches of mechanical properties of them are necessary. One of the most important mechanical characteristics of saturated soft clay is its cyclic accumulative deformation under cyclic loadings. For saturated soft clay, the cyclic accumulative deformation is similar to the creep behavior under static loadings. Therefore, the cyclic accumulative deformation is equivalent to the creep, the number of loading cycles is seen as the time, and this study develops a practical method for predicting the cyclic accumulative deformation of saturated soft clay with the creep theory. The method is a pseudostatic elasto-plastic finite element method implemented by ABAQUS software. A fitted equation between cyclic accumulative strain and number of loading cycles and the empirical relationship of parameters of fitted equation were established with aseries of cyclic triaxial compression tests. Then with this empirical relationship of parameters, the method developed by this study was employed to predict the cyclic accumulative deformation under cyclic triaxial tension tests. Predicted results were in good agreement with test results, and the effectiveness of this method was thus validated for different stress states. The method was then applied in analyzing the cyclic accumulative deformation for soft soil foundation of a pile-supported wharf structure.

关键词： Saturated soft clay Finite elementmethod Soil tests Cyclic accumulativedeformation Creep theory

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Optimal Stiffness for Flexible Connectors on A Mobile Offshore Base at Rough Sea States

引用

China Ocean Engineering 2018年第6期32卷 683-695页

作者： WU Lin-jian wang yuan-zhan wang Yu-chi CHEN Jia-yu LI Yi LI Qing-mei XIE Tao State Key Laboratory of Hydraulic Engineering Simulation and Safety Collaborative Innovation Center for Advanced Ship and Deep-Sea ExplorationTianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China College of Engineering Ocean University of ChinaQingdao 266100China Chongqing Shipping Engineering Survey and Design Institute of the Yangtze River Chongqing 401147China School of River&Ocean Engineering Chongqing Jiaotong UniversityChongqing 400074China

This paper investigates a simplified method to determine the optimal stiffness of flexible connectors on a mobile offshore base(MOB) during the preliminary design stage. A three-module numerical model of an MOB was used as a case study. Numerous constraint forces and relative displacements for the connectors at rough sea states with different wave angles were utilized to determine the optimized stiffness of the flexible connectors. The range of optimal stiffnesses for the connectors was obtained based on the combination and intersection of the optimized stiffness results, and the implementation steps were elaborated in detail. The percentage reductions of the optimized and optimal stiffness of the flexible connector were determined to quantitatively evaluate the decreases of the constraint force and relative displacement of the connectors compared with those calculated by using the original range of the connector stiffnesses. The results indicate the accuracy and feasibility of this method for determining the optimal stiffness of the flexible connectors and demonstrate the rationality and practicability of the optimal stiffness results. The research ideas, calculation process, and solutions for the optimal stiffness of the flexible connectors of an MOB in this paper can provide valuable technical support for the design of the connectors in similar semisubmersible floating structures.

关键词： mobile offshore base(MOB) flexible connectors the optimal stiffness rough sea states

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Bridging microstructure and crystallography with the crack propagation behavior in Ti-6Al-4V alloy fabricated via dual laser beam bilateral synchronous welding

引用

Journal of Materials Science & Technology 2024年第7期174卷 1-14页

作者： Tingyan Yan yuan Liu Jianfeng wang Yong Zheng Xiaohong zhan College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China

The microstructure evolution and crack propagation behavior were systematically and thoroughly inves-tigated inα/βTi-6Al-4V alloy obtained under the inhomogeneous heating effect of a coupled dual laser beam via a combination of postmortem electron backscattering diffraction analyses and numerical *** effect of microstructural attributes(grain size,grain boundary,dislocation)on the fracture property and crack propagation behavior was investigated based on thermodynamic and crystallographic analyses,as well as the examinations of dislocation density and the Burgers *** quantifying the degree of variant selection using the degree of variant selection(DVS)equation,it was found that the higher the energy input,the weaker the variant selection,as the secondaryαphase suppresses further dislocation-induced variant selection via autocatalytic nucleation and *** proportion of high an-gle grain boundaries(HAGBs)concentrated around 60°gradually increases with improving cooling rate,mainly due to the change in the tendency of martensite transformation to be *** grain refine-ment was the primary mechanism for the enhancement of Ti-6Al-4V alloy T-joints,while the suppression of crack propagation by HAGBs also played a crucial role in improving strength and *** crack propagation direction frequently changes when the order is approximately parallel to the short axis ofαmartensite grains,forming a zigzag propagation *** above findings should shed light on optimiz-ing dual laser beam bilateral synchronous welding(DLBSW)technology to tailor the microstructure and improve the mechanical properties of Ti-6Al-4V alloy T-joints.

关键词： Ti-6Al-4V alloy Microstructure Grain refinement Crack propagation Dual laser beam bilateral synchronous welding

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Effects of acupuncture on hypothalamic–pituitary–adrenal axis:Current status and future perspectives

引用

Journal of Integrative Medicine 2024年第4期22卷 445-458页

作者： Jia-yuan Zheng Jing Zhu Yu wang zhan-zhuang Tian Department of Integrative Medicine and Neurobiology School of Basic Medical SciencesState Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain ScienceInstitutes of Brain ScienceInstitute of Acupuncture ResearchAcademy of Integrative MedicineShanghai Key Laboratory for Acupuncture Mechanism and Acupoint FunctionShanghai Medical CollegeFudan UniversityShanghai 200032China Department of Human Anatomy School of Integrative MedicineShanghai University of Traditional Chinese MedicineShanghai 201203China

The hypothalamic–pituitary–adrenal(HPA) axis is a critical component of the neuroendocrine system,playing a central role in regulating the body's stress response and modulating various physiological processes. Dysregulation of HPA axis function disrupts the neuroendocrine equilibrium, resulting in impaired physiological functions. Acupuncture is recognized as a non-pharmacological type of therapy which has been confirmed to play an important role in modulating the HPA axis and thus favorably targets diseases with abnormal activation of the HPA axis. With numerous studies reporting the promising efficacy of acupuncture for neuroendocrine disorders, a comprehensive review in terms of the underlying molecular mechanism for acupuncture, especially in regulating the HPA axis, is currently in need. This review fills the need and summarizes recent breakthroughs, from the basic principles and the pathological changes of HPA axis dysfunction, to the molecular mechanisms by which acupuncture regulates the HPA axis. These mechanisms include the modulation of multiple neurotransmitters and their receptors, neuropeptides and their receptors, and microRNAs in the paraventricular nucleus,hippocampus, amygdala and pituitary gland, which alleviate the hyperfunctioning of the HPA *** review comprehensively summarizes the mechanism of acupuncture in regulating HPA axis dysfunction for the first time, providing new targets and prospects for further exploration of acupuncture.

关键词： Acupuncture Electroacupuncture Hypothalamic-pituitary-adrenal axis Mechanism Neurotransmitter microRNA

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Numerical Analyses of Caisson Breakwaters on Soft Foundations Under Wave Cyclic Loading

引用

China Ocean Engineering 2016年第1期30卷 1-18页

作者：王元战焉振王禹迟 National Key Laboratory of Water Conservancy Engineering Simulation and Security Collaborative Innovation Center for Advanced Ship and Deep-Sea ExplorationTianjin University

A caisson breakwater is built on soft foundations after replacing the upper soft layer with sand. This paper presents a dynamic finite element method to investigate the strength degradation and associated pore pressure development of the intercalated soft layer under wave cyclic loading. By combining the undrained shear strength with the empirical formula of overconsolidation clay produced by unloading and the development model of pore pressure, the dynamic degradation law that describes the undrained shear strength as a function of cycle number and stress level is derived. Based on the proposed dynamic degradation law and M-C yield criterion, a dynamic finite element method is numerically implemented to predict changes in undrained shear strength of the intercalated soft layer by using the general-purpose FEM software ABAQUS, and the accuracy of the method is verified. The effects of cycle number and amplitude of the wave force on the degradation of the undrained shear strength of the intercalated soft layer and the associated excess pore pressure response are investigated by analyzing an overall distribution and three typical sections underneath the breakwater. By comparing the undrained shear strength distributions obtained by the static method and the quasi-static method with the undrained shear strength distributions obtained by the dynamic finite element method in the three typical sections, the superiority of the dynamic finite element method in predicting changes in undrained shear strength is demonstrated.

关键词： soft layer strength degradation pore pressure development wave cyclic loading dynamic finite element method

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Dynamic Stability Analysis of Caisson Breakwater in Lifetime Considering the Annual Frequency of Severe Storm

引用

China Ocean Engineering 2015年第2期29卷 287-300页

作者：王禹迟王元战洪宁宁 State Key Laboratory for Simulation & Safety of Hydraulic Engineering Collaborative Innovation Center for Advanced Ship and Deep-Sea ExplorationTianjin University

In the dynamic stability analysis of a caisson breakwater, most of current studies pay attention to the motion characteristics of caisson breakwaters under a single periodical breaking wave excitation. And in the lifetime stability analysis of caisson breakwater, it is assumed that the caisson breakwater suffers storm wave excitation once annually in the design lifetime. However, the number of annual severe storm occurrence is a random variable. In this paper, a series of random waves are generated by the Wen Sheng-chang wave spectrum, and the histories of successive and long-term random wave forces are built up by using the improved Goda wave force model. It is assumed that the number of annual severe storm occurrence is in the Poisson distribution over the 50-year design lifetime, and the history of random wave excitation is generated for each storm by the wave spectrum. The response histories of the caisson breakwater to the random waves over 50-year design lifetime are calculated and taken as a set of samples. On the basis of the Monte Carlo simulation technique, a large number of samples can be obtained, and the probability assessment of the safety of the breakwater during the complete design lifetime is obtained by statistical analysis of a large number of samples. Finally, the procedure of probability assessment of the breakwater safety is illustrated by an example.

关键词： caisson breakwater dynamic stability lifetime wave spectrum annual storm frequency

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of Al content on modification behavior of non-metallic inclusions in high-strength steel treated with rare earth

引用

Journal of Iron and Steel Research International 2024年第8期31卷 1886-1899页

作者： zhan-peng Tie Xue-yuan Jiang Hai-yan Tang ·Gen Li Yu-hang wang Jia-quan zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Continuous Casting Business Section CISDI Engineering Co.Ltd.Chongqing 401122China Special Steel Institute Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

The influence of Al content(0.0053,0.0171,and 0.0578 wt.%)on the modification behavior of non-metallic inclusions in 20CrMoVTiB steel treated with rare earth elements was studied through high-temperature experiments and thermodynamic *** results showed that the modification products varied with the Al content in steel under 0.01 wt.%of Ce *** formation sequence of typical rare earth inclusions in steel with the increase in Al content was Ce_(2)O_(3)→CeAlO_(3)→CeAl_(11)O_(18),and the final stable products were highly Al content *** the Al content was 0.0053 wt.%,the stable phase in steel was Ce2O3;while the[Al]reached 0.0171 wt.%,the stable phase became CeA1O_(3).As the A1 content reached 0.0578 wt.%,CeAl_(11)O_(18) became the stable *** a result,increasing the Al content could inhibit the precipitation of Ce_(2)O_(3) inclusions in steel while promote the formation of CeAIO3 and CeAl_(11)O_(18) *** addition,both Ca treatment and Ce treatment could effectively refine the size of inclusions in steel by changing their ***,the feeding amount of Ca wire into molten steel should be appropriately reduced under the condition of adding Ce simultaneously,which is expected to be beneficial for an improved Ce treatment effect.

关键词： Rare earth Al content Steel Inclusion Thermodynamics Ca treatment

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Lithium Sulfur Batteries:Insights from Solvation Chemistry to Feasibility Designing Strategies for Practical Applications

引用

Energy & Environmental Materials 2024年第4期7卷 5-27页

作者： Jian Tan Longli Ma yuan wang Pengshu Yi Chuming Ye zhan Fang Zhiheng Li Mingxin Ye Jianfeng Shen Institute of Special Materials and Technology Fudan University Department of Materials Science Fudan University Department of Chemistry Fudan University

Rechargeable lithium-sulfur (Li-S) batteries,featuring high energy density,low cost,and environmental friendliness,have been dubbed as one of the most promising candidates to replace current commercial rechargeable Li-ion ***,their practical deployment has long been plagued by the infamous"shuttle effect"of soluble Li polysulfides (LiPSs) and the rampant growth of Li dendrites.

关键词： characterization tools design strategies Li–S batteries practical applications solvation chemistry

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

New clinical trial design in precision medicine:discovery,development and direction

引用

Signal Transduction and Targeted Therapy 2024年第4期9卷 1293-1321页

作者： Xiao-Peng Duan Bao-Dong Qin Xiao-Dong Jiao Ke Liu zhan wang yuan-Sheng Zang Department of Medical Oncology Changzheng HospitalNaval Medical UniversityShanghaiChina

In the era of precision medicine,it has been increasingly recognized that individuals with a certain disease are complex and different from each *** to the underestimation of the significant heterogeneity across participants in traditional"one-sizefits-all"trials,patient-centered trials that could provide optimal therapy customization to individuals with specific biomarkers were developed including the basket,umbrella,and platform trial designs under the master protocol *** recent years,the successive FDA approval of indications based on biomarker-guided master protocol designs has demonstrated that these new clinical trials are ushering in tremendous *** the rapid increase in the number of basket,umbrella,and platform trials,the current clinical and research understanding of these new trial designs,as compared with traditional trial designs,remains *** majority of the research focuses on methodologies,and there is a lack of in-depth insight concerning the underlying biological logic of these new clinical trial ***,we provide this comprehensive review of the discovery and development of basket,umbrella,and platform trials and their underlying logic from the perspective of precision ***,we discuss future directions on the potential development of these new clinical design in view of the"Precision Pro","Dynamic Precision",and"Intelligent Precision".This review would assist trial-related researchers to enhance the innovation and feasibility of clinical trial designs by expounding the underlying logic,which be essential to accelerate the progression of precision medicine.

关键词： clinical approval successive

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：