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Performance-based seismic assessment of a historical masonry arch bridge: Effect of pulse-like excitations

《结构与土木工程前沿（英文）》   页码 855-869 doi: 10.1007/s11709-023-0972-z

摘要： Seismic analysis of historical masonry bridges is important for authorities in all countries hosting such cultural heritage assets. The masonry arch bridge investigated in this study was built during the Roman period and is on the island of Rhodes, in Greece. Fifteen seismic records were considered and categorized as far-field, pulse-like near-field, and non-pulse-like near-field. The earthquake excitations were scaled to a target spectrum, and nonlinear time-history analyses were performed in the transverse direction. The performance levels were introduced based on the pushover curve, and the post-earthquake damage state of the bridge was examined. According to the results, pulse-like near-field events are more damaging than non-pulse-like near-field ground motions. Additionally the bridge is more vulnerable to far-field excitations than near-field events. Furthermore, the structure will suffer extensive post-earthquake damage and must be retrofitted.

关键词： masonry arch bridges     seismic behavior     modal properties     pulse-like records     nonlinear time history analysis    

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Nonlinear dynamics of a wind turbine tower

A. GESUALDO, A. IANNUZZO, F. PENTA, M. MONACO

《机械工程前沿（英文）》 2019年 第14卷 第3期   页码 342-350 doi: 10.1007/s11465-019-0524-3

摘要： The recent proliferation of wind turbines has revealed problems in their vulnerability under different site conditions, as evidenced by recent collapses of wind towers after severe actions. Analyses of structures subjected to variable actions can be conducted through several methods with different accuracy levels. Nonlinear dynamics is the most reliable among such methods. This study develops a numerical procedure to obtain approximate solutions for rigid-plastic responses of structures subjected to base harmonic pulses. The procedure’s model is applied to a wind turbine tower subjected to inertial forces generated by harmonic ground acceleration, and failure is assumed to depend on the formation of shear hinges. The proposed approach provides an efficient representation of the post-elastic behavior of the structure, has a low computational cost and high effectiveness, and uses a limited number of mechanical parameters.

关键词： nonlinear dynamics     plastic shear failure     modal approximation     time history    

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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    

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Regional seismic-damage prediction of buildings under mainshock–aftershock sequence

Xinzheng LU, Qingle CHENG, Zhen XU, Chen XIONG

《工程管理前沿（英文）》 2021年 第8卷 第1期   页码 122-134 doi: 10.1007/s42524-019-0072-x

摘要： Strong aftershocks generally occur following a significant earthquake. Aftershocks further damage buildings weakened by mainshocks. Thus, the accurate and efficient prediction of aftershock-induced damage to buildings on a regional scale is crucial for decision making for post-earthquake rescue and emergency response. A framework to predict regional seismic damage of buildings under a mainshock–aftershock (MS–AS) sequence is proposed in this study based on city-scale nonlinear time-history analysis (THA). Specifically, an MS–AS sequence-generation method is proposed to generate a potential MS–AS sequence that can account for the amplification, spectrum, duration, magnitude, and site condition of a target area. Moreover, city-scale nonlinear THA is adopted to predict building seismic damage subjected to MS–AS sequences. The accuracy and reliability of city-scale nonlinear THA for an MS–AS sequence are validated by as-recorded seismic responses of buildings and simulation results in published literature. The town of Longtoushan, which was damaged during the Ludian earthquake, is used as a case study to illustrate the detailed procedure and advantages of the proposed framework. The primary conclusions are as follows. (1) Regional seismic damage of buildings under an MS–AS sequence can be predicted reasonably and accurately by city-scale nonlinear THA. (2) An MS–AS sequence can be generated reasonably by the proposed MS–AS sequence-generation method. (3) Regional seismic damage of buildings under different MS–AS scenarios can be provided efficiently by the proposed framework, which in turn can provide a useful reference for earthquake emergency response and scientific decision making for earthquake disaster relief.

关键词： regional seismic damage prediction     city-scale nonlinear time-history analysis     mainshock–aftershock sequence     multiple degree-of-freedom (MDOF) model     2014 Ludian earthquake    

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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

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Parametric study on damage control design of SMA dampers in frame-typed steel piers

Xiaoqun LUO, Hanbin GE, Tsutomu USAMI,

《结构与土木工程前沿（英文）》 2009年 第3卷 第4期   页码 384-394 doi: 10.1007/s11709-009-0065-7

摘要： This paper focuses on damage control design of SMA dampers in steel frame piers. A parametric study based on time history analyses is carried out on frame-typed bridge piers with axial-type SMA damping device. The parameters examined are design parameters of strength ratio and stiffness ratio . Seismic performance indexes on displacement and strain are investigated under three JRA recommended Level 2 Ground Type П strong earthquake motions. Design recommendations are suggested following the results of the parametric study.

关键词： damage control design     shape memory alloy     parameter study     displacement-based verification     strain-based verification     time history analysis    

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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    

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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    

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Seismic analysis of a super high-rise steel structure with horizontal strengthened storeys

Yuanqing WANG, Hui ZHOU, Yongjiu SHI, Yi HUANG, Gang SHI, Siqing WEN

《结构与土木工程前沿（英文）》 2011年 第5卷 第3期   页码 394-404 doi: 10.1007/s11709-011-0116-8

摘要： Horizontal strengthened storeys are widely used in super high-rise steel structures to improve the lateral structural rigidity. This use has great effects on the seismic properties of the entire structure. The seismic properties of the Wuhan International Securities Building (a 68-storey super high-rise steel structure with three horizontal strengthened storeys) were evaluated in this study. Two approaches, i.e., mode-superposition response spectrum analysis and time-history analysis, were employed to calculate the seismic response of the structure. The response spectrum analysis indicated that transition parts near the three strengthened storeys were weak zones of the structure because of the abrupt change in rigidity. In the response spectrum analysis approach, the Square Root of Sum of Square (SRSS) method was recommended when the vertical seismic effects could be ignored. However, the complete quadratic combination (CQC) method was superior to SRSS method when the vertical seismic effects should be considered. With the aid of time-history analysis, the seismic responses of the structure were obtained. The whiplash effect that spectrum analysis cannot reveal was observed through time-history analysis. This study provides references for the seismic design of super high-rise steel structures with horizontal strengthened storeys.

关键词： seismic analysis     steel structure     super high-rise     horizontal strengthened storey     response spectrum analysis     time-history analysis    

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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.
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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    

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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    

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Association between history of abortion and metabolic syndrome in middle-aged and elderly Chinese women

null

《医学前沿（英文）》 2013年 第7卷 第1期   页码 132-137 doi: 10.1007/s11684-013-0250-x

摘要：

Epidemiologic studies have suggested that abortion may cause long term health consequences such as cardiovascular disease. Until recently, studies focusing on the association between history of abortion and metabolic diseases were limited. In the present study, we aimed to investigate the association between history of abortion and metabolic syndrome (MetS) in middle-aged and elderly Chinese women. A cross-sectional survey was performed in 6302 women (age≥40 years) in Shanghai. Standardized questionnaire was used to obtain the information about reproductive histories. Overall, we observed a positive association between history of induced abortion and the prevalence of MetS, independent of potential confounding factors. A multivariable-adjusted logistic regression analysis revealed that compared to those without a history of induced abortion, women with a history of induced abortion remained at 1.25 times more likely to have MetS (OR=1.25, 95% CI=1.06–1.47, P<0.05), and the association was number-dependent. However, no significant association between history of spontaneous abortion and the prevalence of MetS was observed. Compared to those without a history of spontaneous abortion, the multivariate-adjusted odds ratio associated with a history of spontaneous abortion for MetS was 0.88 (95% CI=0.65–1.19, P >0.05).

关键词： induced abortion     spontaneous abortion     metabolic syndrome    

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CROP-LIVESTOCK INTEGRATION FOR SUSTAINABLE AGRICULTURE IN CHINA: THE HISTORY OF STATE POLICY GOALS, REFORM

《农业科学与工程前沿（英文）》 2023年 第10卷 第4期   页码 518-529 doi: 10.15302/J-FASE-2023525

摘要：

This paper examines the historical evolution of crop-livestock integration in China with a specific focus on its role in mitigating non-point source pollution. Extensive examination of existing literature has unearthed the roots of crop-livestock integration dating back to the Western Zhou Dynasty (1046 to 771 BCE), ultimately culminating in a multifaceted and intricately interwoven system of rural development policies seen in contemporary China. This paper identifies and characterizes four distinct stages in the historical trajectory of crop-livestock integration: the era of self-sufficient subsistence production in traditional times (1046 BCE to 1948); the period where crop-livestock integration emerged as a pivotal strategy for augmenting grain and meat production under collectivist policies (1949‒1977); the phase marked by the industrialization and expansion of the livestock sector during the early years of economic reforms (1978‒2011); and the present era in which crop-livestock integration is harnessed as a mechanism for pollution control and ecological preservation in contemporary China (2012 to present). This paper illuminates the diverse contributions of crop-livestock integration in different epochs of rural development within China, which contributes to a nuanced and more theoretically grounded comprehension of circular agriculture. This understanding has the potential to be leveraged to promote sustainable rural development in broader contexts.

关键词： crop-livestock integration     non-point source pollution control     nutrient cycling     policy intervention     sustainable development    

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Self-propelled automatic chassis of Lunokhod-1: History of creation in episodes

Mikhail MALENKOV

《机械工程前沿（英文）》 2016年 第11卷 第1期   页码 60-86 doi: 10.1007/s11465-016-0370-5

摘要：

This report reviews the most important episodes in the history of designing the self-propelled automatic chassis of the first mobile extraterrestrial vehicle in the world, Lunokhod-1. The review considers the issues in designing moon rovers, their essential features, and the particular construction properties of their systems, mechanisms, units, and assemblies. It presents the results of exploiting the chassis of Lunokhod-1 and Lunokhod-2. Analysis of the approaches utilized and engineering solutions reveals their value as well as the consequences of certain defects.

关键词： moon rover     self-propelled chassis     propulsion     wheel     suspension     soil properties     cross-country ability    

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标题 作者 时间 类型 操作

Performance-based seismic assessment of a historical masonry arch bridge: Effect of pulse-like excitations

期刊论文

Nonlinear dynamics of a wind turbine tower

A. GESUALDO, A. IANNUZZO, F. PENTA, M. MONACO

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

Regional seismic-damage prediction of buildings under mainshock–aftershock sequence

Xinzheng LU, Qingle CHENG, Zhen XU, Chen XIONG

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

Parametric study on damage control design of SMA dampers in frame-typed steel piers

Xiaoqun LUO, Hanbin GE, Tsutomu USAMI,

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

Seismic analysis of a super high-rise steel structure with horizontal strengthened storeys

Yuanqing WANG, Hui ZHOU, Yongjiu SHI, Yi HUANG, Gang SHI, Siqing WEN

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

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

Association between history of abortion and metabolic syndrome in middle-aged and elderly Chinese women

null

期刊论文

CROP-LIVESTOCK INTEGRATION FOR SUSTAINABLE AGRICULTURE IN CHINA: THE HISTORY OF STATE POLICY GOALS, REFORM

期刊论文

Self-propelled automatic chassis of Lunokhod-1: History of creation in episodes

Mikhail MALENKOV

期刊论文