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

Patterning mechanisms controlling digit development

引用

Journal of Genetics and Genomics 2008年第9期35卷 517-524页

作者： Jianxin Hu lin he Bio-X Center Shanghai Jiao Tong University Shanghai 200030 China Institute for Nutritional Sciences Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China Institutes of Biomedical Sciences Fudan University Shanghai 200032 China

Vertebrate digits are essential structures for movement, feeding and communication. Specialized regions of the developing limb bud including the zone of polarizing activity （ZPA）, the apical ectodermal ridge （AER）, and the non-ridge ectoderm regulate the patterning of digits. Although a series of signaling molecules have been characterized as patterning signals from the organizing centers, the delicate cellular and molecular mechanisms that interpret how these patterning signals control the detailed digit anatomy remain unclear, Recent studies from model organisms and human hand malformations provide new insights into the mechanisms regulating this process. here, we review the current understanding of the genetic networks governing digit morphogenesis

关键词： digit formation AER ZPA Shh gradient Fgf, patterning mechanism specification elongation segmentation

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 Broadband Geoacoustic Inversion Scheme

引用

Chinese Physics Letters 2004年第6期21卷 1100-1103页

作者： LIZheng-lin ZHANGRen-he NationalLaboratoryofAcoustics InstituteofAcousticsChineseAcademyofSciencesBeijing100080

A geoacoustic inversion scheme, which combines several inversion methods together to invert for the bottom parameters, has been proposed based on the fact that the bottom acoustic parameters have different sensitivities to the different physical parameters of acoustic field. Firstly, the characteristic impedance of the bottom is inverted by measuring the vertical bottom reflective coefficients. Secondly, the derived bottom characteristic impedance is used as a constrained condition in another inversion procedure, which is very sensitive to the bottom sound speed but less sensitive to the attenuation, to inverse the bottom sound speed and bottom density. Lastly, the bottom attenuation can be estimated from methods such as transmission loss data, the vertical correlation of propagation data, and the normal mode attenuation. To obtain the characteristic impedance of the bottom accurately, vacuum glass spheres (VGS) are used as broadband sound sources, and a special mechanism is designed to trigger the VGS imploded at the preset depth. The inversion scheme has been successfully used for a set of sea experimental data. It shows that the inverted bottom parameters could distinguish the atlas marked bottom type quite well. The excellent comparison of the numerical results with the experimental data shows the validity of the inverted parameters.

关键词： Acoustic fields

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

Photocatalytic reduction of CO2 over Sm-doped TiO2 nanoparticles

引用

Journal of Rare Earths 2020年第12期38卷 1297-1304页

作者： Hao Peng Ruitang Guo he lin School of Mechanical and Power Engineering Shanghai Jiaotong UniversityShanghai 200240China College of Energy and Mechanical Engineering Shanghai University of Electric PowerShanghai 200090China Shanghai Engineering Research Center of Power Generation Environment Protection Shanghai 200090China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Highly efficient photocatalytic reduction of CO2 is essential for solving the greenhouse effect and energy *** this paper,the Sm-TiO2 nanocomposites were successfully prepared via sol-gel *** CO2 photoreduction activities of synthesized samples were tested under irradiation for 6 h and the results indicate that the 0.5% Sm-TiO2 catalyst has superior performance and *** CO and CH4 yields of0.5% Sm-TiO2 catalyst are 55.47 and 3.82 μmol/g·cat respectively,which are 5.02 and 2.67 times the yield of *** possible mechanism of Sm doped TiO2 was investigated through comprehensive characterization and photoetectrochemical analysis,After the Sm doping,the photo-generated electrons in TiO2 could migrate to Sm 4 f,and some of them can be captured by reducing Sm3+ o Sm2+,which can lower the recombination rate of electron and hole ***,the enhanced photocatalytic performance could be ascribed to large specific surface area,fast separation rate of electron-hole pairs and high visible light *** report provides some meaningful attempts in researching the CO2 photocatalytic reduction.

关键词： Photocatalyst Sm-TiO2 CO2 reduction Electron-hole pairs Rare earths

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

Recent progresses of quantum confinement in graphene quantum dots

引用

Frontiers of physics 2022年第3期17卷 9-33页

作者： Si-Yu Li lin he Key Laboratory for Micro-Nano Physics and Technology of Hunan Province College of Materials Science and EngineeringHunan UniversityChangsha 410082China Center for Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China

Graphene quantum dots (GQDs) not only have potential applications on spin qubit, but also serve as essential platforms to study the fundamental properties of Dirac fermions, such as Klein tunneling and Berry phase. By now, the study of quantum confinement in GQDs still attract much attention in condensed matter physics. In this article, we review the experimental progresses on quantum confinement in GQDs mainly by using scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS). here, the GQDs are divided into Klein GQDs, bound-state GQDs and edge-terminated GQDs according to their different confinement strength. Based on the realization of quasi-bound states in Klein GQDs, external perpendicular magnetic field is utilized as a manipulation approach to trigger and control the novel properties by tuning Berry phase and electron–electron (e–e) interaction. The tip-induced edge-free GQDs can serve as an intuitive mean to explore the broken symmetry states at nanoscale and single-electron accuracy, which are expected to be used in studying physical properties of different two-dimensional materials. Moreover, high-spin magnetic ground states are successfully introduced in edge-terminated GQDs by designing and synthesizing triangulene zigzag nanographenes.

关键词： graphene quantum dot scanning tunneling microscopy scanning tunneling spectroscopy quasi-bound state bound state triangulene

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

Topological insula tor: Spintronics and quantum computations

引用

Frontiers of physics 2019年第4期14卷 5-20页

作者： Mengyun he Huimin Sun Qing lin he International Center for Quantum Materials School of Physics Peking University Beijing 100871 China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Beijing 100190 China

Topological insulators are emergent states of quantum matter that are gapped in the bulk with timereversal symmetry-pteserved gapless edge/surface states, adiabatically distinct from conventional mat erials. By proximity to various magnets and superconductors, to pological insula tors show novel physics at the interfaces, which give rise to two new areas named topological spintronics and topological quantum compu tat ion. Effects in the former such as the spin to rques, spin-charge conversion, to pological antiferromagnetic spintronics, and skyrmions realized in topological systems will be addressed. In the latter, a superconducting pairing gap leads to a state that supports Majorana fermions states, which may provide a new path for realizing to pological quantum comp ut at ion. Various signa tu res of Majorana zero modes/edge mode in topological superconductors will be discussed. The review ends by outlooks and potential applications of topological insulators. Topological superconductors that are fabricated using topological insulators with superconductors have a full pairing gap in the bulk and gapless surface states consisting of Majorana fermions. The theory of topological superconductors is reviewed, in close analogy to the theory of topological insulators.

关键词： topological insulator Majorana fermion topological spintronics topological superconductor

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

GAGMS: a requirement-driven general address generation and management system

引用

Science China(Information Sciences) 2018年第9期61卷 126-140页

作者： Ying LIU lin he Gang REN Institute for Network Sciences and Cyberspace Tsinghua University Tsinghua National Laboratory for Information Science and Technology

IPv6 address generation is closely related to the manageability, security, privacy protection, and traceability of the Internet. There are many kinds of IPv6 address generation and configuration methods in the area of Internet standards and research that may cause certain problems, including the mixed operation problem of multiple IPv6 address generation schemes, the synchronization problem of the change in IPv6 address, the efficiency problem of processing large-scale concurrent IPv6 address requests, and the general model problem for mapping IPv6 addresses to other requirement spaces as identifiers. In this paper, we consider generating and managing IPv6 addresses according to network requirements. After conducting a requirement analysis of most proposed address generation schemes, we propose a general address generation model and a general address management system, which are the cores of the general address generation and management system(GAGMS). This system solves the above problems under the premise of maintaining the diversity and flexibility of the existing IPv6 address generation and configuration methods and allows networks to utilize different address generation schemes according to different requirements in different scenarios. Finally, we design a prototype system and evaluate our GAGMS to demonstrate its effectiveness,manageability, and scalability, and we have conducted trial deployment in campus networks and are trying to standardize this work in IETF.

关键词： IPv6 address generation IPv6 address management requirement analysis DHCPv6 SLAAC

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

Recent progress in the study of hedgehog signaling

引用

Journal of Genetics and Genomics 2008年第3期35卷 129-137页

作者： Gang Ma Yue Xiao lin he Bio-X Center Shanghai Jiao Tong University Shanghai 200030 China Institute for Nutritional Sciences Shanghai Institutes for Biological Sciences （SIBS） Chinese Academy of Sciences Shanghai 200031 China Institutes of Biomedical Sciences Fudan University Shanghai 200032 China

The hedgehog （Hh） family of secreted signaling proteins plays a critical role in regulating the development of several tissues and organ systems. The ability of Hh proteins to exert their biological effects is regulated by a series of post-translational processes. These processes include an intramolecular cleavage, covalent addition of cholesterol and/or palmitate, and conversion into a multimeric freely diffusible form. The processing of Hh proteins affects their trafficking, potency, and ability to signal over several cell diameters. here we review the current understanding of the Hh signaling mechanisms that govern the establishment of the Hh gradient and the transduction of the Hh signal in the light of recent data.

关键词： hedgehog processing signal transduction

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 Characteristics and Adiabatic heating during High Strain Rate for TRIP Steel and DP Steel

引用

Journal of Iron and Steel Research International 2015年第1期22卷 48-54页

作者： Yi GAO Chao XU Zhong-ping he Yan-lin he lin LI School of Materials Science and Engineering Shanghai University

By using a static and high-speed material testing machine, tensile deformation behaviors of two kinds of Si- Mn TRIP （transformation induced plasticity） steels and DP （dual phase） steel were studied in a large range of strain rates （0.001-2000 s 1）. Temperature variation during adiabatic heating and the amount of retained austenite at fracture were measured by an infrared thermometer and an Xray stress analyser, respectively. The microstructure of steels was observed by optical microscopy （OM） and scanning electron microscopy （SEM） before and after tensile test. It was found from the experimental results that the tensile strength of these steels increased, and the fracture elonga- tion firstly decreased and subsequently increased, as the strain rate increased in the range ＂of 0.1 - 2000 s -1. The temperature raised during adiabatic heating of TRIP steel was in the range of 100- 300℃, while that of the DP steel was in the range of 100-220℃ . The temperature rise of these steels increased with increasing the strain rate, as well as the amount of the transformed retained austenite in TRIP steels. It was confirmed that austenite to martensite transformation is not suppressed by adiabatic heating.

关键词： strain rate TRIP steel adiabatic heating retained austenite

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

Physics-constrained neural network for solving discontinuous interface K-eigenvalue problem with application to reactor physics

引用

Nuclear Science and Techniques 2023年第10期34卷 178-200页

作者： Qi-Hong Yang Yu Yang Yang-Tao Deng Qiao-lin he he-lin Gong Shi-Quan Zhang School of Mathdematics Sichuan UniversityChengdu 610065China Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China

Machine learning-based modeling of reactor physics problems has attracted increasing interest in recent *** some progress in one-dimensional problems,there is still a paucity of benchmark studies that are easy to solve using traditional numerical methods albeit still challenging using neural networks for a wide range of practical *** present two networks,namely the Generalized Inverse Power Method Neural Network(GIPMNN)and Physics-Constrained GIPMNN(PC-GIPIMNN)to solve K-eigenvalue problems in neutron diffusion *** follows the main idea of the inverse power method and determines the lowest eigenvalue using an iterative *** PC-GIPMNN additionally enforces conservative interface conditions for the neutron ***,Deep Ritz Method(DRM)directly solves the smallest eigenvalue by minimizing the eigenvalue in Rayleigh quotient form.A comprehensive study was conducted using GIPMNN,PC-GIPMNN,and DRM to solve problems of complex spatial geometry with variant material domains from the fleld of nuclear reactor *** methods were compared with the standard flnite element *** applicability and accuracy of the methods are reported and indicate that PC-GIPMNN outperforms GIPMNN and DRM.

关键词： Neural network Reactor physics Neutron diffusion equation Eigenvalue problem Inverse power 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

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：