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基于故障分析与诊断综合分析台对减速器的故障研究 被引量:3
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作者 包继华 吕登辉 +1 位作者 张西培 楚宪省 《煤矿机械》 北大核心 2020年第4期148-149,共2页
减速器在工业生产中应用广泛,其故障带来的影响不可忽视。利用山东科大机电科技股份有限公司自主研发的故障分析与诊断综合分析台对减速器的故障进行研究,采集分析台上减速器的运行数据,将小波降噪及傅里叶理论同MATLAB软件结合进行分析... 减速器在工业生产中应用广泛,其故障带来的影响不可忽视。利用山东科大机电科技股份有限公司自主研发的故障分析与诊断综合分析台对减速器的故障进行研究,采集分析台上减速器的运行数据,将小波降噪及傅里叶理论同MATLAB软件结合进行分析,得出减速器运行状态评估。 展开更多
关键词 减速器 分析台 小波降噪 MATLAB
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南海深水钻井平台悬挂隔水管撤离防台分析 被引量:13
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作者 许亮斌 周建良 +2 位作者 王荣耀 蒋世全 盛磊祥 《中国海上油气》 CAS CSCD 北大核心 2015年第3期101-107,共7页
南海深水钻井作业面临台风等环境挑战,如何有效应对台风影响,降低台风对深水钻井作业带来的挑战与风险,是目前必须要解决的关键问题。针对南海台风的实际情况,给出了抗台、按计划撤离和悬挂隔水管撤离等3种应对措施。在此基础上,针对南... 南海深水钻井作业面临台风等环境挑战,如何有效应对台风影响,降低台风对深水钻井作业带来的挑战与风险,是目前必须要解决的关键问题。针对南海台风的实际情况,给出了抗台、按计划撤离和悬挂隔水管撤离等3种应对措施。在此基础上,针对南海某深水井隔水管配置,以钻井平台航速作为隔水管顶部的动边界,建立了1 500 m隔水管的有限元模型,重点分析了钻井平台悬挂隔水管撤离时的悬挂隔水管响应,得到了顺流向和逆流向钻井平台悬挂1 500 m长隔水管实施撤离时的航速范围,以及隔水管不同悬挂长度时钻井平台安全撤离的航速范围,从而为南海深水钻井平台现场防台作业提供了参考依据。 展开更多
关键词 深水钻井平 悬挂隔水管撤离 分析 南海
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高速公路隧道二衬错台剖析及防治措施 被引量:2
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作者 苏长柄 《福建交通科技》 2013年第3期31-33,共3页
隧道二衬施工时,由于多种因素,两模接头容易出现大量错台,严重影响外观质量。为解决这一疑难问题,笔者结合工程实践,进行了大量研究,分析了二衬错台产生的主要原因,总结出科学有效的隧道二衬错台防治措施。
关键词 隧道 二衬 原因分析 防治措施
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基于PLC的三维微量移液伺服控制系统
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作者 田鹏 张子刚 《计算技术与自动化》 2008年第2期36-38,43,共4页
论述基于PC+PLC的交流伺服系统在三维空间随机定位以及在生化分析操作台上的应用实例。该操作台方法简单可靠、定位准确、响应速度快。掉电重启后可以精确复位,运行速度可调,并有位置监控和故障报警功能,人机对话界面友好。并提出一种... 论述基于PC+PLC的交流伺服系统在三维空间随机定位以及在生化分析操作台上的应用实例。该操作台方法简单可靠、定位准确、响应速度快。掉电重启后可以精确复位,运行速度可调,并有位置监控和故障报警功能,人机对话界面友好。并提出一种微量移液控制算法:采用特制移液针头精确有效地将生物试剂移取,提高系统的工作效率。 展开更多
关键词 PLC 生化分析台 微量移液 控制算法 伺服系统
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2003年新疆巴楚—伽师地震序列的双差法重新定位研究 被引量:92
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作者 黄媛 杨建思 张天中 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2006年第1期162-169,共8页
将近台记录和区域台网数据联合用于双差地震定位算法,对2003年新疆巴楚-伽师M56.8强震后404个ML≥3.5余震序列进行双差法重新精确定位,并对其进行了理论上的可行性分析.精定位后定位结果与传统定位方法的原始定位结果进行比较发现... 将近台记录和区域台网数据联合用于双差地震定位算法,对2003年新疆巴楚-伽师M56.8强震后404个ML≥3.5余震序列进行双差法重新精确定位,并对其进行了理论上的可行性分析.精定位后定位结果与传统定位方法的原始定位结果进行比较发现:(1)精定位后震中分布图像更加集中,与当地的烈度考察和震源机制解结果更加协调;(2)震源深度优势分布集中在15-25km以内,与当地存在深度为10km以上低速沉积层的地质构造情况相一致;(3)精定位后定位残差由原来的3.94s降为0.24s,水平向估算误差平均可控制在1.1km以内,垂直向估算误差平均可控制在2.4km. 展开更多
关键词 余震序列 双差地震定位算法 影响分析 巴楚-伽师地震
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Theoretical analysis on springback of L-section extrusion in rotary stretch bending process 被引量:13
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作者 于成龙 李小强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2705-2710,共6页
The theoretical analysis of springback in rotary stretch bending process of L-section extrusion was studied. The models for characterizing the springback angle after unloading were established based on the stress and ... The theoretical analysis of springback in rotary stretch bending process of L-section extrusion was studied. The models for characterizing the springback angle after unloading were established based on the stress and strain distributions in the cross-section of the part. With the proposed model, analysis of the effect of pre-stretch force and post-stretch force on springback angle shows that springback decreases as the pre-stretch force or post-stretch force increases. Comparative study with experiments clearly demonstrates that the prediction of springback can resort to the current model without the loss of accuracy. 展开更多
关键词 SPRINGBACK rotary stretch bending theoretical analysis
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The Kuroshio front to the east of Taiwan: seasonal feature, variability and mechanism
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作者 王琦 李威 +3 位作者 马继瑞 韩桂军 张学峰 王喜东 《Marine Science Bulletin》 CAS 2011年第2期13-32,共20页
Oceanic front, especially Kuroshio front, is an important phenomenon that is of great significance for scientific research, national economy and military uses. However, Kuroshio front to the east of Taiwan (KFETW in ... Oceanic front, especially Kuroshio front, is an important phenomenon that is of great significance for scientific research, national economy and military uses. However, Kuroshio front to the east of Taiwan (KFETW in brief) was rare investigated. In this study, reanalysis method is used to study the KFETW's temporal and spatial variability and frontogenesis mechanism. It is found that although surface thermal front to the east of Taiwan is not obvious, there is an all-year strong Kuroshio thermal front called KFETW under the surface. The KFETW is connected to the south section of Kuroshio front in the East China Sea (KFECS in brief) and distributes along the east coastline of Taiwan. The KFETW has multi-scale variation feature. It has significant seasonal signal, and its intensity and width reach their maximum in summer. By using the reanalysis results obtained from this study, frontogenesis and changing mechanisms of the KFETW are discussed. It is found that both the Kuroshio and up-welling to the east of Taiwan can affect this front, and the up-welling may be the predominant factor in KFETW's frontogenesis and maintenance mechanism. 展开更多
关键词 Kuroshio front the east of Taiwan REANALYSIS seasonal feature frontogenesis
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Analyzing the safety of removal sequences for piles of an offshore jacket platform
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作者 潘新颖 张兆德 《Journal of Marine Science and Application》 2009年第4期311-315,共5页
An inevitable consequence of the development of the offshore petroleum industry is the eventual obsolescence of large offshore structures. Proper methods for removal of decommissioned offshore platforms are becoming a... An inevitable consequence of the development of the offshore petroleum industry is the eventual obsolescence of large offshore structures. Proper methods for removal of decommissioned offshore platforms are becoming an important topic that the oil and gas industry must pay increasing attention to. While removing sections from a decommissioned jacket platform, the stability of the remaining parts is critical The jacket danger indices D ~ and Ds defined in this paper are very useful for analyzing the safety of any procedure planned for disassembling a jacket platform. The safest piles cutting sequence can be determined easily by comparing every column of Do and Ds or simply analyzing the figures of every row ofD o and D,. 展开更多
关键词 jacket platform REMOVAL safety analysis STRESS
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Study on the Meso-scale process of the Kuroshio front to the east of Taiwan
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作者 王琦 李威 +2 位作者 马继瑞 韩桂军 张学峰 《Marine Science Bulletin》 CAS 2011年第1期10-24,共15页
By using the reanalysis data, the impact of oceanic eddies and frontal wave on Kuroshio front to the east of Taiwan (KFETW) is studied. The result indicates that cold eddies (warm eddies) corresponding to the firs... By using the reanalysis data, the impact of oceanic eddies and frontal wave on Kuroshio front to the east of Taiwan (KFETW) is studied. The result indicates that cold eddies (warm eddies) corresponding to the first baroclinic mode of Rossby wave can weaken (strengthen) the strength of the KFETW and narrow (widen) the width of this front. A frontal wave of the KFETW during January to February in 1991 is detected from the reanalysis data. And the trough (crest) of the frontal wave may weaken (strengthen) the strength of the KFETW and narrow (widen) the width and thickness of this front. It is found through the diagnostic analysis of the energy source of the frontal wave that the contribution of barotropic instability or that of baroclinic instability is more than that of Ketvin-Helmholtz (K-H) instability by 1 - 2 order of magnitude, and the contribution of the baroclinic instability is 5 times than that of the barotropic instability, thereby the frontal wave is basically driven by the baroclinic instability. 展开更多
关键词 Kuroshio front the east of Taiwan REANALYSIS oceanic eddy frontal wave
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可搬移式无线电信号检测系统的建设
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作者 林锦顺 《通信对抗》 2004年第3期50-52,共3页
介绍了一种可搬移式无线电检测系统的建设,通过密集型、立体型、高灵敏度、智能化信号检测网络的设计以解决无线电信号的频谱监测和管理,系统可在不同地点、不同区域对可疑无线信号进行监测,快速发现可疑无线电信号,并对信号进行监... 介绍了一种可搬移式无线电检测系统的建设,通过密集型、立体型、高灵敏度、智能化信号检测网络的设计以解决无线电信号的频谱监测和管理,系统可在不同地点、不同区域对可疑无线信号进行监测,快速发现可疑无线电信号,并对信号进行监听、参数测量和识别、简单定位,系统具有很强的机动性。 展开更多
关键词 监测接收机 监测分析显控 比幅法测向 无线电信号 检测系统
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Extratropical Transition and Re-Intensification of Typhoon Toraji(2001):Large-Scale Circulations, Structural Characteristics, and Mechanism Analysis 被引量:1
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作者 ZHU XiANDe WU Lixin WANG Qi 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期461-476,共16页
With the use of data from the National Centers for Environmental Prediction Climate Forecast System Reanalysis,the environment and structure of typhoon Toraji(2001)are investigated during the re-intensification(RI)sta... With the use of data from the National Centers for Environmental Prediction Climate Forecast System Reanalysis,the environment and structure of typhoon Toraji(2001)are investigated during the re-intensification(RI)stage of its extratropical transition(ET),a process in which a tropical cyclone transforms into an extratropical or mid-latitude cyclone.The results provide detailed insight into the ET system and identify the specific features of the system,including wind field,a cold and dry intrusion,and a frontal structure in the RI stage.The irrotational wind provides the values of upper-and lower-level jets within the transitioning tropical cyclone and the cyclone over Shandong Peninsula,accompanied with the reduced radius of maximum surface winds around the cyclone center in the lower troposphere.Simultaneously,dry air intrusion enhances the formation of fronts and leads to strong potential instability in the southwest and northeast quadrants.The distribution of frontogenesis shows that the tilting term associated with vertical motion dominates the positive frontogenesis surrounding the cyclone center,especially in the RI stage.The diagnostics of the kinetic energy budget suggest that the divergent kinetic energy generation whose time evolution corresponds well to that of cyclone center pressure is the primary factor for the development of Toraji in the lower troposphere.The ET of Toraji is a compound pattern that contains a development similar to that of a B-type extratropical cyclone within the maintaining phase and an A-type extratropical cyclone within the strengthening period,which corresponds to the distribution of the E-P fluxes with vertically downward propagation in the maintaining stage and upwards momentum in the strengthening phase. 展开更多
关键词 typhoon Toraji extratropical transition re-intensification upper level jet FRONTOGENESIS energy budget
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Wave load computation in direct strength analysis of semi-submersible platform structures 被引量:7
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作者 ZHANGHai-bin RENHui-long DAIYang-shan GEFei 《Journal of Marine Science and Application》 2004年第1期7-13,共7页
A wave load computation approach in direct strength analysis of semi-submersible platform structures was presented in this paper. Considering the differences in shape of pontoon, column and beam, the combination of ac... A wave load computation approach in direct strength analysis of semi-submersible platform structures was presented in this paper. Considering the differences in shape of pontoon, column and beam, the combination of accumulative chord length cubic parameter spline theory and analytic method was adopted for generating the wet surface mesh of platform. The hydrodynamic coefficients of platform were calculated by the three-dimensional potential flow theory of the linear hydrodynamic problem for platform with low forward speed. The equation of platform motions was established and solved in frequency domain, and the responses of wave-induced loads on the platform can be obtained. With the interpolation method being utilized, the pressure loads on shell elements for finite element analysis (FEA) were converted from those on the hydrodynamic computation mesh, which pave the basis for FEA with commercial software.A computer program based on this method has been developed, and a calculation example of semi-submersible platform was illustrated.Analysis results show that this method is a satisfying approach of wave loads computation for this kind of platform. 展开更多
关键词 semi-submersible platform wave loads mesh-generating direct strength analysis
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Using analytic network process to analyze problems for implementing turn-key construction projects in Taiwan 被引量:3
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作者 王丹绮 王隆昌 《Journal of Central South University》 SCIE EI CAS 2011年第2期558-567,共10页
The turn-key construction project is implemented in Taiwan not by a single company but by a make-shift group of several companies. Hence,problems to coordinate the professional construction management (PCM) and the su... The turn-key construction project is implemented in Taiwan not by a single company but by a make-shift group of several companies. Hence,problems to coordinate the professional construction management (PCM) and the supervising architectural company often occur for the lack of long-term experience to work together. The various factors that affect the implementation of turn-key projects currently practiced in Taiwan are analyzed using the analytic network process (ANP). The objective is to study how the twelve key factors in the four layers of "Role assignment","Signing contract","Operational procedures" and "Losing capital investment" affect the progress of implementing the turn-key project in Taiwan. The results reveal that "Delay in payment" has the most negative influence with 15.62% weighing factor; "Latent risk" comes next with 11.14% weighing factor,and "Responsibility of construction company for project quality" is the third with 10.79% weighing factor. 展开更多
关键词 turn-key turn-key construction company professional construction management analytic network process (ANP)
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ANALYSES OF WIND STRUCTURE OF TYPHOON FUNG-WONG (2008) AND ITS RELATION TO PRECIPITATION REGION 被引量:3
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作者 周玉淑 刘黎平 《Journal of Tropical Meteorology》 SCIE 2009年第2期192-203,共12页
Using real analysis data of 1°×1° resolution of the National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR),the nondivergent wind component and irrotational win... Using real analysis data of 1°×1° resolution of the National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR),the nondivergent wind component and irrotational wind component obtained by the harmonic-cosine(H-C) method,and the wind structure of Typhoon Fung-Wong (coded 0808 in China) in 2008 was analyzed. The results indicated that the irrotational component was advantageous over the total wind in reflecting both the changes in convergent height and the asymmetrical convergence of Fung-Wong. In Fung-Wong,the nondivergent component was larger than the irrotational component,but the latter was much more variable than the former,which was obtained only from the wind partition method. Further analyses on the irrotational component demonstrated that the location of the convergent center at lower levels was almost the same as the divergent center during the development of Fung-Wong,and its convergent level was high in its life cycle,with the most highest up to 400 hPa when it became stronger. After the typhoon landed in the provinces of Taiwan and Fujian,respectively,its convergent center at lower levels was slowly detached from the divergent center at high levels and the convergent height was also depressed from high levels to lower levels. Gradually,this weakened the intensity of Fung-Wong. This kind of weakening was slow and Fung-Wong maintained its circulation for a long time over land because of its very thick convergent height. Analyses on wind partitioning provided one possible explanation to why Fung-Wong stayed for a long time after it landed. Furthermore,the asymmetric vertical ascending motion was induced by the asymmetric convergence at lower levels. In general,when typhoons (such as Fung-Wong) land,the rainfall region coincides with that of the convergence region (indicated by the irrotational component at lower layers). This means that the possible rainfall regions may be diagnosed from the convergent area of the irrotational component. For an observational experiment on typhoons,the convergent region may be considered as a key observational region. 展开更多
关键词 wind partitioning typhoon Fung-Wong structure analysis
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Stochastic Analysis of Nonlinear Coupled Heave-Pitch Motion for the Truss Spar Platform 被引量:1
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作者 沈文君 唐友刚 《Journal of Marine Science and Application》 2011年第4期471-477,共7页
Considering the static stability and the change of the displacement volume, including the influences of higher order nonlinear terms and the instantaneous wave surface, the nonlinear coupled heave-pitch motion was est... Considering the static stability and the change of the displacement volume, including the influences of higher order nonlinear terms and the instantaneous wave surface, the nonlinear coupled heave-pitch motion was established in stochastic waves. The responses of heave-pitch coupling motion for the Truss Spar platform were investigated. It was found that, when the characteristic frequency of a stochastic wave is close to the natural heave frequency, the large amplitude pitch motion is induced under the parametric-forced excitation, which is called the Mathieu instability. It was observed that the heave mode energy is transferred to pitch mode when the heave motion amplitude exceeds a certain extent. In addition, the probability of internal resonant heave-pitch motion is greatly reduced while the characteristic wave frequency is away from the natural heave frequency. 展开更多
关键词 Truss Spar platform heave-pitch nonlinear coupling stochastic waves parametric-forcedexcitation Mathieu instability
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Integrated and Intelligent Manufacturing: Perspectives and Enablers 被引量:32
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作者 Yubao Chen 《Engineering》 SCIE EI 2017年第5期588-595,共8页
With ever-increasing market competition and advances in technology, more and more countries are prioritizing advanced manufacturing technology as their top priority for economic growth. Germany announced the Industry ... With ever-increasing market competition and advances in technology, more and more countries are prioritizing advanced manufacturing technology as their top priority for economic growth. Germany announced the Industry 4.0 strategy in 2013. The US government launched the Advanced Manufacturing Partnership (AMP) in 2011 and the National Network for Manufacturing Innovation (NNMI) in 2014. Most recently, the Manufacturing USA initiative was officially rolled out to further "leverage existing resources... to nurture manufacturing innovation and accelerate commercialization" by fostering close collaboration between industry, academia, and government partners. In 2015, the Chinese government officially published a 10- year plan and roadmap toward manufacturing: Made in China 2025. In all these national initiatives, the core technology development and implementation is in the area of advanced manufacturing systems. A new manufacturing paradigm is emerging, which can be characterized by two unique features: integrated manufacturing and intelligent manufacturing. This trend is in line with the progress of industrial revolutions, in which higher efficiency in production systems is being continuously pursued. To this end, 10 major technologies can be identified for the new manufacturing paradigm. This paper describes the rationales and needs for integrated and intelligent manufacturing (i2M) systems. Related technologies from different fields are also described. In particular, key technological enablers, such as the Intemet of Things and Services (IoTS), cyber-physical systems (CPSs), and cloud computing are discussed. Challenges are addressed with applica- tions that are based on commercially available platforms such as General Electric (GE)'s Predix and PTC's ThingWorx. 展开更多
关键词 Integrated manufacturing Intelligent manufacturing Cloud computing Cyber-physical system Internet of Things Industrial Internet Predictive analytics Manufacturing platform
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Novel approach for determining the optimal axial preload of a simulating rotary table spindle system 被引量:7
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作者 SHAN Xiao-biao XIE Tao CHEN Wei-shan 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第5期812-817,共6页
This paper presents a new theoretical model to determine the optimal axial preload of a spindle system, for challenging the traditional method which relies heavily on experience of engineers. The axial preloading stif... This paper presents a new theoretical model to determine the optimal axial preload of a spindle system, for challenging the traditional method which relies heavily on experience of engineers. The axial preloading stiffness was treated as the sum of the spindle modal stiffness and the framework elastic stiffness, based on a novel concept that magnitude of preloads can be controlled by measuring the resonant frequency of a spindle system. By employing an example of a certain type of aircraft simulating rotary table, the modal stiffness was measured on the Agilent 35670A Dynamic Signal Analyzer by experimental modal analysis. The equivalent elastic stiffness was simulated by both finite element analysis in ANSYS? and a curve fitting in MATLAB?. Results showed that the static preloading stiffness of the spindle was 7.2125×107 N/m, and that the optimal preloading force was 120.0848 N. Practical application proved the feasibility of our method. 展开更多
关键词 Three-axis simulating rotary table Axial position preload STIFFNESS Experimental modal analysis Finite elementanalysis
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Elastic-plastic study on high building with SRC transferring story 被引量:1
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作者 李玉荣 裘涛 孙炳楠 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第3期407-414,共8页
A new type of transferring structure for steel reinforced concrete (SRC) beams is used in high building. The pushover analysis method was used to study the failure mechanism and ductility of SRC transferring structure... A new type of transferring structure for steel reinforced concrete (SRC) beams is used in high building. The pushover analysis method was used to study the failure mechanism and ductility of SRC transferring structure through consulting pseudo-static test results for the structure. And, the occurrence order and position of the plastic hinge, the weak story and seismic capacity of high building with SRC transferring story were also studied through consulting shaking table test results for the high building, showing that the seismic behavior of high building with SRC transferring story is good. 展开更多
关键词 Steel reinforced concrete (SRC) Transferring structure for SRC beams Static pushover analysis High building Pseudo-static test Shaking table test
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GIS applications in typhoon simulation and Hazard assessment 被引量:5
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作者 常亮 段忠东 欧进萍 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第4期383-387,共5页
GIS technology provides a powenful tool for disaster hazard assessment and mitigation. A GIS based system is developed for typhoon data management and analysis, typhoon simulation and hazard assessment for southeast c... GIS technology provides a powenful tool for disaster hazard assessment and mitigation. A GIS based system is developed for typhoon data management and analysis, typhoon simulation and hazard assessment for southeast coast of China in this paper. A typhoon database by Microsoft Access is designed. Data manipulation and analysis, typhoon simulation and hazard assessment, and visualization of results are implemented on GIS platform. This GIS-based typhoon database and analysis system greatly facilitates typhoon hazard assessment. 展开更多
关键词 GIS TYPHOON hazard analysis disaster mitigation
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Developing a Risk Assessment Model for Typhoon-triggered Debris Flows 被引量:2
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作者 Jieh-Jiuh WANG Hoe I.LING 《Journal of Mountain Science》 SCIE CSCD 2011年第1期10-23,共14页
A methodology is developed for interactive risk assessment of physical infrastructure and spatially distributed response systems subjected to debris flows.The proposed framework is composed of three components,namely ... A methodology is developed for interactive risk assessment of physical infrastructure and spatially distributed response systems subjected to debris flows.The proposed framework is composed of three components,namely geotechnical engineering,geographical information systems and disaster management.With the integration of slope stability analysis,hazard scenario and susceptibility,geological conditions are considered as temporary static data,while meteorological conditions are treated as dynamic data with a focus on typhoons.In this research,the relevant parameters required for database building are defined,and the procedures for building the geological database and meteorological data sets are explained.Based on the concepts and data sets,Nantou and Hualien in Taiwan are used as the areas for case studies. 展开更多
关键词 Debris flow disaster HAZARD RISK VULNERABILITY Slope stability
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