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The interdependence and complexity of socio-technical systems and availability of a wide variety of policy measures to address policy problems make the process of policy formulation difficult. In order to formulate sustainable and efficient transport policies, development of new tools and techniques is necessary. One of the approaches gaining ground is policy packaging, which shifts focus from implementation of individual policy measures to implementation of combinations of measures with the aim of increasing efficiency and effectiveness of policy interventions by increasing synergies and reducing potential contradictions among policy measures. In this paper, we describe the development of a virtual environment for the exploration and analysis of different configurations of policy measures in order to build policy packages. By developing systematic approaches it is possible to examine more alternatives at a greater depth, decrease the time required for the overall analysis, provide real-time assessment and feedback on the effect of changes in the configurations, and ultimately form more effective policies. The results from this research demonstrate the usefulness of computational approaches in addressing the complexity inherent in the formulation of policy packages. This new approach has been applied to the formulation of policies to advance sustainable transportation. 相似文献
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Structural fatigue is a design driver for offshore wind turbines (OWT). In particular, the substructures, like jackets, are strongly affected by fatigue. Monitoring the fatigue progression in the welds is vital for the maintenance and a potential lifetime extension. However, inspections of critical locations are costly due to the limited accessibility of the mostly submerged jacket. Considering the high number of potentially critical welds, it is regarded as economically unfeasible to equip all fatigue hot spots with sensors. Thus, an indirect method to monitor the fatigue progress of the structure and point out critical locations is desirable. For a consistent support of ongoing maintenance, it has to yield reliable results for varying operational and environmental conditions. This paper applies a virtual sensing approach to jacket substructures. From a small set of sensors on the tower, fatigue at every desired location of the jacket is estimated using dual-band modal expansion. Simulations using the OC4 jacket design are performed to show potentials and limitations of the method. Namely fatigue progress on leg welds of K-joints is predicted with high accuracy over a wide range of load cases. However, some difficulties in fatigue prediction of X-joints due to the occurrence of local modes and limitations in the extrapolation of wave loading have to be resolved in future work. 相似文献
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介绍了基于LabVIEW图形化的虚拟仪器设计、构成、特点及其发展现状和前景。根据电容器补偿原理,提出软件设计思路,利用软件对实测的数据进行了分析,提出补偿意见,达到了预期目的。 相似文献
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文章以黄冈职业技术学院在"电气控制线路的安装与调试"课程中开展的虚拟仿真技术开发和教学方面为例,揭示了虚拟仿真技术在当前高职教学中的重要作用。指出利用虚拟仿真技术辅助高职教学可以解决实验、实训设备短缺、教学方法和手段落后、教学效果不理想等问题,对培养学生的动手能力和创新意识具有深远的影响。 相似文献
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本文简要介绍了试验室数据采集系统的组成和主要实现技术,详细介绍了数采系统及其软件程序的各个组成部分,该程序实现了对试验室的各种数据进行采集、实时显示、海量数据存储、查询数据、定制报表和图表等。该数据采集系统具有采集精度高、实时性强、可靠性高和操作简便灵活等特点。 相似文献
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针对某中型客车,利用ADAMS软件建立了空气悬架客车动力学仿真模型,并进行了随机路面输入及三角凸台路面输入的平顺性仿真分析。仿真结果与试验数据对比表明,在测量点处的最大加速度、自功率谱密度及其对应的频率点比较接近,说明所建立的仿真模型是准确的。对影响客车平顺性的2个参数在ADAMS中进行了优化。 相似文献