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101.
城市轨道交通综合监控项目工程实施管理的难点是进度控制和接口协调.以上海轨道交通7号线综合监控项目为例,介绍了工程进度控制和接口协调的方法及项目实施经验.为把软件开发团队纳入项目部的管理范围为项目工程进度的控制提供了组织保障,接口协议分析工具和第三方接口测试认证等是接口协调的技术保障,自主软件平台及其软件开发团队、技术协... 相似文献
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伍军 《铁道科学与工程学报》2010,7(1)
针对传统施工进度管理工具在表现方式上的缺陷,提出应用3维可视化进行桥梁施工管理的重要性。结合桥梁3维模型、施工进度和资源强度计划,创建了桥梁施工进度及资源管理4D仿真模型,开发了大型桥梁施工过程3维仿真系统。利用该系统可以结合桥梁3维模型,对桥梁施工进度计划、资源需求情况进行动态模拟,方便用户对施工进度及资源强度等信息进行可视化的预测和查询,实现了桥梁施工项目的可视化管理和控制,为4D-CAD及仿真技术在桥梁施工管理中的进一步研究与应用提供了重要思路。 相似文献
104.
IntroductionThe basic idea in active contour models orsnakes is to evolve a curve,subject to constraintsfrom a given image,in order to detect objects inthat image.For instance,starting with a curvearound the object to be detected,the curve movestoward its interior normal and has to stop on theboundary of the object.LetΩ be a bounded open subset of R2 ,with Ω its boundary. Let u0 ∶Ω→ R be a given image,and C( s)∶ [0 ,1 ]→ R2 be a parameterized curve. Inthe classical snakes and active… 相似文献
105.
Asphalt mixtrues exhibit strong viscous properties under repetitive loads.This phenomenon can be simulated in creep and recovery tests.By applying the visco-elastoplastic model proposed,data recorded in the tests are interpreted.It is emphasised that applicability of the visco-elastoplastic model depends on the proper method of characterising parameters involved in the constitutive equations.Since two or more strain components of elasticity and viscosity coexist during the loading or unloading,a measuring system of two loggers is introduced to decouple these components.Test data are analysed in three steps as elastic.visco-elastic and visco-plastic evaluations,using the records collected at the moment of unloading,during the periods of recovery and creep respectively,Factors that may influence the accuracy of data analysis are also discussed. 相似文献
106.
金峻炎 《华东交通大学学报》2013,(6):44-48
为了使工程项目进度计划更具有可操作性以及对进度的可控性,在编制项目进度计划过程中引入基于精益思想TFV理论的最后计划者系统。通过该系统的项目主计划、前瞻计划以及周计划的编制与实施,将进度计划的编制从传统的“推式”系统转变为“拉式”系统,可以实现项目计划的动态跟踪与管理。基于案例比较分析,证实该方法可以提高项目进度计划的有效性和可操作性。 相似文献
107.
设计了针对计算机电磁信息泄漏的接收和再现系统.用宽带天线截获电磁信息泄漏信号后,经带通滤波和放大,再用锁相环电路捕获帧同步与行同步信号.同步信号经模数转换后,得到视频数字信号的输出.然后,用平均滤波法对数字视频信号降噪.最后,用匹配滤波器获得再现的文字.测试结果表明,用平均滤波的方法使同步信号的信噪比提高了18.7 dB,可在12 m范围内获取奔腾486主机及阴极射线管显示器泄漏的文字信息. 相似文献
108.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(2):201-217
With the advent of flywheel-based kinetic energy recovery systems in automotive applications new safety issues arise as a consequence of the flywheel's high rotational speed. While the special structural safety requirements of the components are well discussed in the literature, there is still little research on the influence of gyroscopic effects on vehicle dynamics. The aim of this paper is to investigate the influence of a typical high-speed flywheel on the driving dynamics of an average passenger car. To this end the equations of motion of a gyroscope are derived, which relate the vehicle's roll, pitch and yaw rate with the transverse torque acting on the flywheel. These equations are implemented in a commercial vehicle dynamics simulation program in order to determine the reaction torques acting on the vehicle within a representative range of driving situations. Numerical simulations indicate that the gyroscopic effect can be considered insignificant in standard driving situations. 相似文献
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The analysis of the causes behind the appearance and propagation of delays is one of the major topics inside Air Transport Management research. Existing research focuses by and large on Air Traffic Flow Management regulations and reactionary delays; less attention has been devoted to the study of the mechanisms governing the generation and absorption of delays while airborne, in spite of their important economical and environmental consequences. Here we present a methodology to detect delay-generating events, based on the comparison of planned and real trajectories; these events are then used to characterise several aspects of the dynamics of the system, e.g. its resilience. We apply this methodology to a historical data set of flights crossing the European airspace during 2011, and observe an overall resilient system, able to absorb as much delays as it generates; yet resilience is not constant, but strongly depends on the phase of the flight, and shows high spatial and temporal heterogeneities. We anticipate the proposed methodology to open new doors for the development of a better systemic performance, by enabling the characterisation and understanding of this fundamental type of delay. 相似文献