资源类型

期刊论文 120

年份

2023 5

2022 8

2021 5

2020 4

2019 12

2018 2

2017 6

2016 6

2014 7

2013 7

2012 4

2011 11

2010 10

2009 8

2008 2

2007 9

2006 4

2005 3

2003 1

2002 1

展开 ︾

关键词

力学性能 3

变形 3

变形监测 3

中医史 2

变形预测 2

围岩变形 2

增材制造 2

数值模拟 2

2016年熊本地震 1

3D打印 1

ALOS-2 PALSAR-2 1

EBSD 1

Inconel 718合金 1

RBF神经网络 1

Rosenthal方程 1

X射线 1

三向受力状态 1

三峡升船机 1

三维形变反演 1

展开 ︾

检索范围：

排序： 展示方式：

Formation mechanism and modeling of surface waviness in incremental sheet forming

《机械工程前沿（英文）》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0679-1

摘要： Improving and controlling surface quality has always been a challenge for incremental sheet forming (ISF), whereas the generation mechanism of waviness surface is still unknown, which impedes the widely application of ISF in the industrial field. In this paper, the formation mechanism and the prediction of waviness are both investigated through experiments, numerical simulation, and theoretical analysis. Based on a verified finite element model, the waviness topography is predicted numerically for the first time, and its generation is attributed to the residual bending deformation through deformation history analysis. For more efficient engineering application, a theoretical model for waviness height is proposed based on the generation mechanism, using a modified strain function considering deformation modes. This work is favorable for the perfection of formation mechanism and control of surface quality in ISF.

关键词： surface waviness     incremental sheet forming     numerical simulation     formation mechanism     deformation history    

HTML PDF 收藏

Advanced finite element analysis of a complex deep excavation case history in Shanghai

Yuepeng DONG, Harvey BURD, Guy HOULSBY, Yongmao HOU

《结构与土木工程前沿（英文）》 2014年 第8卷 第1期   页码 93-100 doi: 10.1007/s11709-014-0232-3

摘要： The construction of the North Square Shopping Center of the Shanghai South Railway Station is a large scale complex top-down deep excavation project. The excavation is adjacent to several current and newly planned Metro lines, and influenced by a neighboring Exchange Station excavation. The highly irregular geometry of this excavation greatly increases the complexity in 3D Finite Element modeling. The advanced numerical modeling described in this paper includes detailed structural and geotechnical behavior. Important features are considered in the analysis, e.g., 1) the small-strain stiffness of the soil, 2) the construction joints in the diaphragm wall, 3) the shrinkage in the concrete floor slabs and beams, 4) the complex construction sequences, and 5) the shape effect of the deep excavation. The numerical results agree well with the field data, and some valuable conclusions are generated.

关键词： advanced finite element analysis     deep excavations     case history     small-strain stiffness    

HTML PDF 收藏

Introduction to the special issue on the 2015 Workshop on History of Mechanism and Machine Science

Marco CECCARELLI

《机械工程前沿（英文）》 2016年 第11卷 第1期   页码 1-2 doi: 10.1007/s11465-016-0379-9

HTML PDF 收藏

Resistance of large deformation of the Wushaoling Tunnel F7 soft fault

ZHAO Xufeng, CHEN Haiming, WANG Chunmiao

《结构与土木工程前沿（英文）》 2007年 第1卷 第1期   页码 123-127 doi: 10.1007/s11709-007-0013-3

摘要： In this article, the mechanical characteristics of the squeeze of the F7 fault of the Wushaoling Tunnel are analyzed. The measurements and techniques are proposed to resist the deformation. The result indicates that the method of construction to control the further squeeze deflection is appropriate.

关键词： F7     deformation     appropriate     construction     mechanical    

HTML PDF 收藏

Numerical modeling of nonlinear deformation of polymer composites based on hyperelastic constitutive

Qingsheng YANG, Fang XU

《机械工程前沿（英文）》 2009年 第4卷 第3期   页码 284-288 doi: 10.1007/s11465-009-0067-0

摘要： Fiber reinforced polymer (FRP) composites exhibit nonlinear and hyperelastic characteristics under finite deformation. This paper investigates the macroscopic hyperelastic behavior of fiber reinforced polymer composites using a micromechanical model and finite deformation theory based on the hyperelastic constitutive law. The local stress and deformation of a representative volume element are calculated by the nonlinear finite element method. Then, an averaging procedure is used to find the homogenized stress and strain, and the macroscopic stress-strain curves are obtained. Numerical examples are given to demonstrate hyperelastic behavior and deformation of the composites, and the effects of the distribution pattern of fibers are also investigated to model the mechanical behavior of FRP composites.

关键词： composites     hyperelastic     finite deformation     homogenization     micromechanics    

HTML PDF 收藏

Natural history of HIV infection in former plasma donors in rural China

Min ZHANG, Hong SHANG, Zhe WANG, Wei-Guo CUI, Qing-Hai HU

《医学前沿（英文）》 2010年 第4卷 第3期   页码 346-350 doi: 10.1007/s11684-010-0102-x

摘要： Patients infected through commercial blood-selling practices (former plasma donors, FPDs) in China represent a unique patient population compared to individuals infected through sexual contact or intravenous drug use. FPDs all have an approximate time of human immunodeficiency virus (HIV) infection during the mid-1990s. Few studies about the natural history of HIV infection in these patients were performed. The current study focuses on characterizing the duration of asymptomatic infection as well as the time to disease and mortality of infected FPDs in China. A retrospective cohort study was conducted based on data collected from 5484 HIV-1 infected FPDs in Shangcai county, Henan province. Kaplan-Meier analysis was applied to estimate the asymptomatic duration from the time of infection to the onset of AIDS as well as the survival period from the onset of AIDS to the time of death. The estimated median asymptomatic phase was about 9.21 years, which is similar to that reported in other developing countries in Africa. The estimated median life span after the onset of symptoms was about 9.91 months, which is notably shorter than life spans reported elsewhere. This is the first large-scale retrospective study on the natural history of HIV infection in FPDs in rural China. The findings not only provide valuable insight into an understudied population, but should also serve as an important reference for patient management and care.

关键词： human immunodeficiency virus (HIV)     former plasma donor     natural history     China    

HTML PDF 收藏

The biopharmaceutical industry in China: history and future perspectives

null

《医学前沿（英文）》 2012年 第6卷 第2期   页码 101-111 doi: 10.1007/s11684-012-0191-9

摘要：

Biopharmaceuticals reflect the rapid progress achieved in modern biomedical research. This area has also become one of the main criteria for assessing the development level of biotechnology for a particular country. Although it has been only three decades since the first biopharmaceutical, recombinant human insulin, was licensed by the US Food and Drug Administration, the biopharmaceutical industry has become the fastest growing, most dynamic and technology-intensive sector in the biomedical field. Since the licensing of recombinant human interferon α1b in 1989, the biopharmaceutical industry in China has gone through initial developments and gradually entered a period of rapid growth. This paper provides an overview of the status and development trends of biopharmaceuticals in China, and compares them with those observed in developed countries.

关键词： biopharmaceuticals     antibodies     market trends     diseases     China     national regulatory agency    

HTML PDF 收藏

A continuous/discontinuous deformation analysis (CDDA) method based on deformable blocks for fracture

Yongchang CAI, Hehua ZHU, Xiaoying ZHUANG

《结构与土木工程前沿（英文）》 2013年 第7卷 第4期   页码 369-378 doi: 10.1007/s11709-013-0222-x

摘要： In the framework of finite element meshes, a novel continuous/discontinuous deformation analysis (CDDA) method is proposed in this paper for modeling of crack problems. In the present CDDA, simple polynomial interpolations are defined at the deformable block elements, and a link element is employed to connect the adjacent block elements. The CDDA is particularly suitable for modeling the fracture propagation because the switch from continuous deformation analysis to discontinuous deformation analysis is natural and convenient without additional procedures. The SIFs (stress intensity factors) for various types of cracks, such as kinked cracks or curved cracks, can be easily computed in the CDDA by using the virtual crack extension technique (VCET). Both the formulation and implementation of the VCET in CDDA are simple and straightforward. Numerical examples indicate that the present CDDA can obtain high accuracy in SIF results with simple polynomial interpolations and insensitive to mesh sizes, and can automatically simulate the crack propagation without degrading accuracy.

关键词： fracture     crack     propagation     deformable block     continuous/discontinuous deformation analysis (CDDA)    

HTML PDF 收藏

Calculation methods of the crack width and deformation for concrete beams with high-strength steel bars

Jianmin ZHOU, Shuo CHEN, Yang CHEN

《结构与土木工程前沿（英文）》 2013年 第7卷 第3期   页码 316-324 doi: 10.1007/s11709-013-0211-0

摘要： Three groups of concrete beams reinforced with high-strength steel bars were tested, and the crack width and deformation of the specimens were observed and studied. To facilitate the predictions, two simplified formulations according to a theory developed by the first author were proposed. The advantages of the formulations were verified by the test data and compared with several formulas in different codes.

关键词： concrete beam     high-strength steel bar     crack width     deformation    

HTML PDF 收藏

Calculation method of radial stress and deformation on conic threaded connections with interference fit

Shoujun CHEN, Qiang LI, Qi AN,

《机械工程前沿（英文）》 2010年 第5卷 第3期   页码 302-307 doi: 10.1007/s11465-010-0018-9

摘要： This paper presents a calculation method for radial stress distribution and deformation on conic threaded connections with interference fit. Based on elastic mechanics, a new calculation model is established using the thick-walled-cylindrical theory. A sample calculation for API 88.9 mm conic threaded connection indicates that the method proposed in this paper is reasonable, and the finite element analysis (FEA) method is used to validate the proposed method. The results obtained by the proposed method and FEA method are identical. The model offers a new way of calculating the radial stress and deformation on conic thread connections with interference fit.

关键词： conic threaded connections     interference fit     radial stress     deformation     finite element analysis (FEA)    

HTML PDF 收藏

Fuzzy cascade control based on control’s history for superheated temperature

WANG Guangjun, LI Gang, SHEN Shuguang

《能源前沿（英文）》 2007年 第1卷 第3期   页码 285-289 doi: 10.1007/s11708-007-0040-8

摘要： To address the characteristics of the large delay and uncertainty of superheated temperature, a new cascade control system is presented based on control’s history. Based on the analysis of the control objects’ dynamic characteristics, historical control information (substituting for the deviation change rate) is used as the basis for decision-making of the fuzzy control. Therefore, the changing trend of the controlled variable can be accurately reflected. Furthermore, a proportional component is introduced, the advantages of PID and fuzzy controllers are integrated, and the structure weaknesses of conventional fuzzy controllers are overcome. Simulation shows that this control method can effectively reduce the adverse impact of the delay on control effects and, therefore, exhibit strong adaptability by comparing the superheated temperature control system by this controller with PID and conventional fuzzy controllers.
HTML PDF 收藏

A brief history of wheat utilization in China

Minxia LU, Liang CHEN, Jinxiu WANG, Ruiliang LIU, Yang YANG, Meng WEI, Guanghui DONG

《农业科学与工程前沿（英文）》 2019年 第6卷 第3期   页码 288-295 doi: 10.15302/J-FASE-2019266

摘要：

Wheat is one of the most important crops in both China and the world, and its domestication can be traced back to ~10000 years ago. However, the history of its origin and utilization in China remains highly ambiguous. Drawing upon the most recent results of taxonomic, genetic, archeological and textual studies focused on the wheat in prehistory, this paper argues that wheat was not domesticated but introduced into China in the late fifth millennium BP. In the subsequent centuries, this exotic crop was quickly utilized as a staple food in northwest China. In contrast, it was not adopted as a staple in Central Plains until the Han Dynasty (202 BCE–220 CE), which was mainly as a consequence of the living environment, population and innovations in food processing technology.

关键词： multidisciplinary evidence     prehistoric food globalization     wheat consumption     wheat domestication    

HTML PDF 收藏

Simulation of blast induced crater in jointed rock mass by discontinuous deformation analysis method

Youjun NING, Xinmei AN, Jun YANG, Guowei MA,

《结构与土木工程前沿（英文）》 2010年 第4卷 第2期   页码 223-232 doi: 10.1007/s11709-010-0022-5

摘要： Rock blasting is a dynamic process accompanied with the propagations of shock waves and the dispersion of the explosion gas. This paper adopts the discontinuous deformation analysis (DDA) method to simulate the rock blasting process. A dynamic parameter adjustment and the non-reflecting boundary condition are implemented in the DDA method. The sub-block DDA method to simulate fracture problems is used. The blasting process in jointed rock mass is simulated by application of the explosion gas pressure on the expanding borehole walls and induced connected fracture surfaces around the boreholes. The blast craters with different overburdens are derived. The whole process including the explosion gas dispersion, borehole expansion, rock mass failure and cast, and the formation of the final blasting piles in rock blasting are well reproduced numerically. Parametric study for different overburdens is carried out, and the results are analyzed and discussed.

关键词： blast crater     jointed rock mass     explosion gas pressure     discontinuous deformation analysis (DDA) method    

HTML PDF 收藏

Rotation errors in numerical manifold method and a correction based on large deformation theory

Ning ZHANG, Xu LI, Qinghui JIANG, Xingchao LIN

《结构与土木工程前沿（英文）》 2019年 第13卷 第5期   页码 1036-1053 doi: 10.1007/s11709-019-0535-5

摘要： Numerical manifold method (NMM) is an effective method for simulating block system, however, significant errors are found in its simulation of rotation problems. Three kinds of errors, as volume expansion, stress vibration, and attenuation of angular velocity, were observed in the original NMM. The first two kind errors are owing to the small deformation assumption and the last one is due to the numerical damping. A large deformation NMM is proposed based on large deformation theory. In this method, the governing equation is derived using Green strain, the large deformation iteration and the open-close iteration are combined, and an updating strategy is proposed. The proposed method is used to analyze block rotation, beam bending, and rock falling problems and the results prove that all three kinds of errors are eliminated in this method.

关键词： numerical manifold method     rotation     large deformation     Green strain     open-close iteration    

HTML PDF 收藏

An overview of the development history and technical progress of China’s coal-fired power industry

Weiliang WANG, Zheng LI, Junfu LYU, Hai ZHANG, Guangxi YUE, Weidou NI

《能源前沿（英文）》 2019年 第13卷 第3期   页码 417-426 doi: 10.1007/s11708-019-0614-2

摘要： As the main power source of China, coal-fired power industry has achieved a great progress in installed capacity, manufacturing technologies, thermal efficiency, as well as pollutant control during the past century. With the fast development of renewable energies, coal-fired power industry is experiencing a strategic transformation. To specify the development of coal-fired power industry, its development history is reviewed and the technical progresses on aspects of thermal efficiency, pollutants control and peaking shaving capacity are discussed. It is concluded that the role of China’s coal-fired power source would be transformed from the dominant position to a base position in power source structure. Considering the sustainable development of coal-fired power industry in energy conservation, emission control, and utilization of renewable energies, it is suggested that the national average thermal efficiency should be improved by continual up-gradation of units by using advanced technologies and eliminating outdated capacity. Moreover, the emission standard of air pollutants should not be stricter any more in coal-fired power industry. Furthermore, the huge amount of combined heat and power (CHP) coal-fired units should be operated in a decoupled way, so as to release more than 350 GW regulation capacity for the grid to accept more renewable energy power.

关键词： coal-fired power     development strategy     eliminating outdated capacity     peak shaving     emission reduction     renewable energy    

HTML PDF 收藏

标题 作者 时间 类型 操作

Formation mechanism and modeling of surface waviness in incremental sheet forming

期刊论文

Advanced finite element analysis of a complex deep excavation case history in Shanghai

Yuepeng DONG, Harvey BURD, Guy HOULSBY, Yongmao HOU

期刊论文

Introduction to the special issue on the 2015 Workshop on History of Mechanism and Machine Science

Marco CECCARELLI

期刊论文

Resistance of large deformation of the Wushaoling Tunnel F7 soft fault

ZHAO Xufeng, CHEN Haiming, WANG Chunmiao

期刊论文

Numerical modeling of nonlinear deformation of polymer composites based on hyperelastic constitutive

Qingsheng YANG, Fang XU

期刊论文

Natural history of HIV infection in former plasma donors in rural China

Min ZHANG, Hong SHANG, Zhe WANG, Wei-Guo CUI, Qing-Hai HU

期刊论文

The biopharmaceutical industry in China: history and future perspectives

null

期刊论文

A continuous/discontinuous deformation analysis (CDDA) method based on deformable blocks for fracture

Yongchang CAI, Hehua ZHU, Xiaoying ZHUANG

期刊论文

Calculation methods of the crack width and deformation for concrete beams with high-strength steel bars

Jianmin ZHOU, Shuo CHEN, Yang CHEN

期刊论文

Calculation method of radial stress and deformation on conic threaded connections with interference fit

Shoujun CHEN, Qiang LI, Qi AN,

期刊论文

Fuzzy cascade control based on control’s history for superheated temperature

WANG Guangjun, LI Gang, SHEN Shuguang

期刊论文

A brief history of wheat utilization in China

Minxia LU, Liang CHEN, Jinxiu WANG, Ruiliang LIU, Yang YANG, Meng WEI, Guanghui DONG

期刊论文

Simulation of blast induced crater in jointed rock mass by discontinuous deformation analysis method

Youjun NING, Xinmei AN, Jun YANG, Guowei MA,

期刊论文

Rotation errors in numerical manifold method and a correction based on large deformation theory

Ning ZHANG, Xu LI, Qinghui JIANG, Xingchao LIN

期刊论文

An overview of the development history and technical progress of China’s coal-fired power industry

Weiliang WANG, Zheng LI, Junfu LYU, Hai ZHANG, Guangxi YUE, Weidou NI

期刊论文