检索结果-南通市图书馆

Numerical investigation of the failure mechanism of cubic concrete specimens in SHPB tests

Defence Technology（防务技术） 2022年第1期18卷 1-11页

作者： Mei Li hong hao Jian Cui Yi-fei hao Labomtory of Coast Civil Structure Safety of Ministry of Education Tianjin UniversityTiarjin300072China chool of Civil Engineering.Tianin University Tianjin300072China entre for Infrastructural Monitoring and Protection School of Civil and Mechanical Engineering Curtin UniversityPerth Western Australia6845Australia

Cylindrical specimens are commonly used in Split Hopkinson pressure bar(SHPB)tests to study the uniaxial dynamic properties of concrete-like *** recent years,true tri-axial SHPB equipment has also been developed or is under development to investigate the material dynamic properties under tri-axial impact *** such tests,cubic specimens are *** is well understood that static material strength obtained from cylinder and cube specimens are *** factors are obtained and adopted in some guidelines to convert the material streng th obtained from the two types of *** uniaxial impact tests have also demonstrated that the failure mode and the strain rate effect of cubic specimens are very different from that of cylindrical ***,the mechanical background of these findings is *** an extension of the previous laboratory study,this study performs numerical SHPB tests of cubic and cylindrical concrete specimens subjected to uniaxial impact load with the validated numerical *** stress states of cubic specimens in relation to its failure mode under different strain rates is analyzed and compared with cylindrical *** detailed analyses of the numerical simulation results show that the lateral inertial confinement of the cylindrical specimen is higher than that of the cubic specimen under the same strain *** cubic specimen,the corners aremore severely damaged because of the lower lateral confinement and the occurrence of the tensile radial stress which is not observed in cylindrical *** results explain why the dynamic material strengths obtained from the two types of specimens are different and are strain rate *** on the simulation results,an empirical formula of conversion factor as a function of strain rate is proposed,which supplements the traditional conversion factor for quasi-static material *** can be used for transforming the dynamic compressive strength from

关键词： Concrete Lateral inertial confinement Shape effet Dynamic failure mechanism Strain rate

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

Analysis of identification methods of key nodes in transportation network

引用

Chinese Physics B 2022年第6期31卷 782-789页

作者： Qiang Lai hong-hao Zhang School of Electrical and Automation Engineering East China Jiaotong UniversityNanchang 330013China

The identification of key nodes plays an important role in improving the robustness of the transportation *** different types of transportation networks,the effect of the same identification method may be *** is of practical significance to study the key nodes identification methods corresponding to various types of transportation *** on the knowledge of complex networks,the metro networks and the bus networks are selected as the objects,and the key nodes are identified by the node degree identification method,the neighbor node degree identification method,the weighted k-shell degree neighborhood identification method(KSD),the degree k-shell identification method(DKS),and the degree k-shell neighborhood identification method(DKSN).Take the network efficiency and the largest connected subgraph as the effective *** results show that the KSD identification method that comprehensively considers the elements has the best recognition effect and has certain practical significance.

关键词： transportation network key node identification KSD identification method network efficiency

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

Performance of double-arch tunnels under internal BLEVE

引用

Underground Space 2024年第6期19卷 6-25页

作者： Ruishan Cheng Wensu Chen hong hao Center for Infrastructural Monitoring and Protection School of Civil and Mechanical EngineeringCurtin UniversityPerth 6000Australia Earthquake Engineering Research&Test Center Guangzhou UniversityGuangzhou 510000China

Double-arch tunnels,as one of the popular forms of tunnels,might be exposed to boiling liquid expanding vapour explosions(BLEVEs)associated with transported liquified petroleum gas(LPG),which could cause damage to the tunnel and even catastrophic collapse of the tunnel in extreme ***,very limited study has investigated the performance of double-arch tunnels when exposed to internal BLEVEs and in most analyses of tunnel responses to accidental *** TNT-equivalence method was used to approximate the explosion load,which may lead to inaccurate tunnel response *** study numerically investigates the response of typical double-arch tunnels to an internal BLEVE resulting from the instantaneous rupture of a 20 m^(3) LPG *** of various factors,including in-situ stresses,BLEVE locations,and lining configurations on tunnel responses are *** results show that the double-arch tunnels at their early-operation ages are more vulnerable to severe damage when exposed to the BLEVE due to the low action of in-situ stress of rock mass on the response of early-age *** is also found that directing the LPG tank to different driving lanes inside tunnels can affect the BLEVE-induced tunnel response more significantly than varying the configurations of tunnel ***,installing section-steel arches in the mid-wall can effectively improve the blast resistance of the double-arch tunnels against the internal *** addition,the prediction models based on multi-variate nonlinear regressions and machine learning methods are developed to predict the BLEVE-induced damage levels of the double-arch tunnels without and with section-steel arches.

关键词： Double-arch tunnel BLEVE Lining configuration Section-steel arch Damage prediction

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

Toward understanding genetic mechanisms of complex traits in rice

引用

Journal of Genetics and Genomics 2010年第10期37卷 653-666页

作者： Wei hao hong-Xuan Li National Key Laboratory of Plant Molecular Genetics Shanghai Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China

Rice is the primary carbohydrate staple cereal feeding the world population. Many genes, known as quantitative trait loci （QTLs）, con- trol most of the agronomically important traits in rice. The identification of QTLs controlling agricultural traits is vital to increase yield and meet the needs of the increasing human population, but the progress met with challenges due to complex QTL inheritance. To date, many QTLs have been detected in rice, including those responsible for yield and grain quality; salt, drought and submergence tolerance; disease and insect resistance; and nutrient utilization efficiency. Map-based cloning techniques have enabled scientists to successfully fine map and clone approximately seventeen QTLs for several traits. Additional in-depth functional analyses and characterizations of these genes will provide valuable assistance in rice molecular breeding.

关键词： rice quantitative trait loci (QTLs) mapping populations marker-assisted selection (MAS) map-based cloning

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

Response of a transmission tower-line system at a canyon site to spatially varying ground motions

引用

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第2期12卷 103-120页

作者： hong-nan LI Feng-long BAI Li TIAN hong hao State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China Sehool of Civil and Resource Engineering University of Western Australia WA 6009 Australia

Collapses of transmission towers were often observed in previous large earthquakes such as the Chi-Chi earthquake in Taiwan and Wenchuan earthquake in Sichuan,China. These collapses were partially caused by the pulling forces from the transmission lines generated from out-of-phase responses of the adjacent towers owing to spatially varying earthquake ground motions. In this paper,a 3D finite element model of the transmission tower-line system is established considering the geometric nonlinearity of transmission lines. The nonlinear responses of the structural system at a canyon site are analyzed subjected to spatially varying ground motions. The spatial variations of ground motion associated with the wave passage,coherency loss,and local site effects are given. The spatially varying ground motions are simulated stochastically based on an empirical coherency loss function and a filtered Tajimi-Kanai power spectral density function. The site effect is considered by a transfer function derived from 1D wave propagation theory. Compared with structural responses calculated using the uniform ground motion and delayed excitations,numerical results indicate that seismic responses of transmission towers and power lines are amplified when considering spatially varying ground motions including site effects. Each factor of ground motion spatial variations has a significant effect on the seismic response of the structure,especially for the local site effect. Therefore,neglecting the earthquake ground motion spatial variations may lead to a substantial underestimation of the response of transmission tower-line system during strong earthquakes. Each effect of ground motion spatial variations should be incorporated in seismic analysis of the structural system.

关键词： Transmission tower-line system Canyon site Spatially varying ground motions Coherency loss Local site effect

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 amplification factors for a system with multiple-degrees-of-freedom

引用

Earthquake Engineering and Engineering Vibration 2020年第2期19卷 363-375页

作者： Zhang Chao hao hong Bi Kaiming Yan Xueyuan College of Civil Engineering Fuzhou UniversityFuzhou 350108China Centre for Infrastructure Monitoring and Protection School of Civil and Mechanical EngineeringCurtin UniversityKent StreetBentley WA 6102Australia Key Laboratory of Urban Security and Disaster Engineering of MOE Beijing University of TechnologyBeijing 100124China

It is well-known that the responses of a structure are different when subjected to a static load or a sudden step *** dynamic amplification factor(DAF),which is defined as the ratio of the amplitude of the vibratory response to the static response,is normally used to depict the dynamic *** a single-degree-of-freedom system(SDOF)subjected to a sudden dynamic load,the maximum value of DAF is *** design guidelines therefore use 2 as an upper bound to consider the dynamic *** a civil engineering structure,which is normally a multiple-degrees-of-freedom(MDOF)system,the DAF may exceed 2 in certain *** adoption of 2 as the upper bond as suggested by the design guidelines therefore may lead to unsafe structural *** limited studies systematically investigate the DAF of a MDOF sysCorrespondence to:Bi Kaiming,Centre for Infrastructure Monitoring and Protection,School of Civil and Mechanical Engineering,Curtin University,Kent Street,Bentley WA 6102,Australia Tel:(+61)892665139 E-mail:***@*** study theoretically investigates the DAF of a MDOF system when it is subjected to a step load based on the fundamental theory of structural *** condition on which the DAF may exceed 2 is *** numerical examples and one experimental study of a cable-stayed bridge subjected to sudden cable loss are presented to illustrate the problem.

关键词： dynamic amplification factors(DAF) multiple-degrees-of-freedom(MDOF) step load

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 Derivation of Strain Rate Effects on Material Properties of Masonry with Solid Clay Bricks

引用

Transactions of Tianjin University 2006年第B9期12卷 147-151页

作者： WEI Xueying hao hong School of Civil and Resource Engineering The University of Western Australia WA6009 Australia

In this paper, numerical method is used als. A typical unit of masonry is selected to serve merical model of RVE is established with detailed to study the strain rate effect on masonry materias a representative volume element （RVE）. Nudistinctive modeling of brick and mortar with their respective dynamic material properties obtained from laboratory tests. The behavior of brick and mortar are characterized by a dynamic damage model that accounts for rate-sensitive and pressuredependent properties of masonry materials. Dynamic loads of different loading rates are applied to RVE. The equivalent homogenized uniaxial compressive strength, threshold strain and elastic modulus in three directions of the masonry are derived from the simulated responses of the RVE. The strain rate effect on the masonry material with clay brick and mortar, such as the dynamic increase factor （DIF） of the ultimate strength and elastic modulus as a function of strain rate are derived from the numerical results.

关键词： masonry structure strain rate effects dynamic increase factor (DIF) elastic modulus ultimate strength

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 prediction of ground vibrations induced by LPG boiling liquid expansion vapour explosion(BLEVE)inside a road tunnel

引用

Underground Space 2023年第5期12卷 44-64页

作者： Ruishan Cheng Wensu Chen hong hao Jingde Li Center for Infrastructural Monitoring and Protection School of Civil and Mechanical EngineeringCurtin UniversityBentley 6102Australia Earthquake Engineering Research&Test Center Guangzhou UniversityGuangzhou 510006China

Accidental boiling liquid expansion vapour explosions(BLEVEs)caused by the bursting of liquified petroleum gas(LPG)tank inside a tunnel can induce vibrations of its surrounding geological media and threaten the stability of adjacent tunnels and ***,it is essential to understand the characteristics of vibrations induced by LPG BLEVEs inside the tunnel for the safety design of its adjacent *** to the difficulty in effectively predicting the LPG BLEVE loads,the current practice usually employs equivalent methods,e.g.,the TNT-equivalency method,in LPG BLEVE load predictions for structural response analysis,which may lead to inaccurate response *** study compares ground vibrations induced by a BLEVE inside an arched road tunnel with those induced by its equivalent TNT explosion via high-fidelity numerical *** results demonstrate that the frequency of BLEVEinduced vibrations is lower than that induced by the TNT explosion at the same scaled *** intensity of LPG BLEVE-induced vibrations at relatively small-scaled distances is lower than that of TNT explosion-induced vibrations at the same scaled distance,but becomes higher after a certain scaled distance because of the relatively low attenuation *** addition,parametric analysis is conducted to evaluate the effects of various factors on the characteristics of LPG BLEVE-induced ground *** is found that the surrounding rock type,the rock porosity,and the cover depth of the tunnel have more significant influences than the concrete grade of the tunnel *** recommendation for the tunnel design is also given based on the intensity and frequency characteristics of BLEVE-induced vibrations.

关键词： Tunnel BLEVE TNT explosion Vibration intensity Vibration frequency

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

Fast and high-fidelity generation of photonic Greenberger-Horne-Zeilinger states in circuit QED

引用

Communications in Theoretical Physics 2020年第1期72卷 52-59页

作者： Jingwei Chen Guan-hao Feng hong-hao Zhang L F Wei School of Physics Sun Yat-sen UniversityGuangzhou 510275China Photonics Laboratory and Institute of Functional Materials College of ScienceDonghua UniversityShanghai 201620China Information Quantum Technology Laboratory School of Information Science and TechnologySouthwest Jiaotong UniversityChengdu 610031China

A fast scheme to generate Greenberger-Horne-Zeilinger states between different cavities in circuit QED systems is *** implement this scheme,we design a feasible experimental device with three qubits and three *** this device,all the couplings between qubit and qubit,cavity and qubit are tunable and are independent with frequencies,and thus the shortcut to adiabaticity technique can be directly applied in our *** is demonstrated that the GHZ state can be generated rapidly with high fidelity in our scheme.

关键词： GHZ states shortcut to adiabaticity quantum state engineering circuit QED

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

A review of enantioselective dual transition metal/photoredox catalysis

引用

Science China Chemistry 2020年第5期63卷 637-647页

作者： hong-hao Zhang Hui Chen Chengjian Zhu Shouyun Yu Jiangsu Key Laboratory of Advanced Organic Materials School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Transition metal catalysis is one of the most important tools to construct carbon-carbon and carbon-heteroatom bonds in modern organic synthesis. Visible-light photoredox catalysis has recently drawn considerable attention of the scientific community owing to its unique activation modes and significance for the green synthesis. The merger of photoredox catalysis with transition metal catalysts, termed metallaphotoredox catalysis, has become a popular strategy for expanding the synthetic utility of visiblelight photocatalysis. This strategy has led to the discovery of novel asymmetric transformations, which are unfeasible or not easily accessible by a single catalytic system. This contemporary area of organic chemistry holds promise for the development of economical and environmentally friendly methods for the asymmetric synthesis of chiral compounds. In this review, the advances in the enantioselective metallaphotoredox catalysis(EMPC) are summarized.

关键词： transition metal catalysis photoredox catalysis dual catalysis asymmetric catalysis

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

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：