随着建设项目日益大型化和复杂化,基于建筑信息模型(Building Information Modeling,BIM)集成应用的信息交流逐渐成为项目沟通的重要途径。然而,在当前BIM应用现状下存在着信息孤岛和信息断层的现象,削弱了BIM技术对建筑业生产效率的积...随着建设项目日益大型化和复杂化,基于建筑信息模型(Building Information Modeling,BIM)集成应用的信息交流逐渐成为项目沟通的重要途径。然而,在当前BIM应用现状下存在着信息孤岛和信息断层的现象,削弱了BIM技术对建筑业生产效率的积极影响。为找出BIM工程信息流的实际传递效果未能达到理想状态的原因,采用文献调查、理论分析等方法,对BIM工程信息流的噪声因素进行梳理,并得到了13个主要噪声因素。将13个噪声因素,利用系统动力学软件Vensim进行BIM工程信息流系统的仿真,对其中的关键因素进行辨析。通过研究得出:政府要求及政策支持度、业主利益分配合理度以及BIM规范的统一性对系统影响较大;施工类BIM软件成熟度对系统的影响比设计类BIM软件成熟度影响大等相关结论,并从中得到启示。本研究有助于BIM应用效益的实现,推动BIM的进一步发展。展开更多
In this paper, the lattice model is presented, incorporating not only site information about preceding cars but also relative currents in front. We derive the stability condition of the extended model by considering a...In this paper, the lattice model is presented, incorporating not only site information about preceding cars but also relative currents in front. We derive the stability condition of the extended model by considering a small perturbation around the homogeneous flow solution and find that the improvement in the stability of traffic flow is obtained by taking into account preceding mixture traffic information. Direct simulations also confirm that the traffic jam can be suppressed efficiently by considering the relative currents ahead, just like incorporating site information in front. Moreover, from the nonlinear analysis of the extended models, the preceding mixture traffic information dependence of the propagating kink solutions for traffic jams is obtained by deriving the modified KdV equation near the critical point using the reductive perturbation method.展开更多
在现代反导作战中,如何规划反导作战指控系统从而缩短目标、指挥信息传输时间和提高指挥精度是很重要的问题。基于此展开讨论,首先设计规划了3种反导作战指控系统信息流时延模型并提出了应用原则,其次分别以一典型3 500 km TBM和不同射...在现代反导作战中,如何规划反导作战指控系统从而缩短目标、指挥信息传输时间和提高指挥精度是很重要的问题。基于此展开讨论,首先设计规划了3种反导作战指控系统信息流时延模型并提出了应用原则,其次分别以一典型3 500 km TBM和不同射程TBM为例进行了时延模型仿真计算和分析,最后通过分析计算结果给出反导作战指控系统建设性结论。展开更多
为有效评估反导作战预警信息流转效能,分析了反导预警的作战过程,建立了基于着色Petri网(colored Petri nets,CPN)的反导预警信息流转模型,并用仿真软件对所建立的模型进行了仿真.通过优选效能评估指标,对反导预警信息流转CPN模型进行...为有效评估反导作战预警信息流转效能,分析了反导预警的作战过程,建立了基于着色Petri网(colored Petri nets,CPN)的反导预警信息流转模型,并用仿真软件对所建立的模型进行了仿真.通过优选效能评估指标,对反导预警信息流转CPN模型进行效能评估和优化.结果分析表明,适当减少用户的数量和传递层级,可以增加信息在用户之间的流转速率,以满足反导预警作战的时效性要求.展开更多
文摘随着建设项目日益大型化和复杂化,基于建筑信息模型(Building Information Modeling,BIM)集成应用的信息交流逐渐成为项目沟通的重要途径。然而,在当前BIM应用现状下存在着信息孤岛和信息断层的现象,削弱了BIM技术对建筑业生产效率的积极影响。为找出BIM工程信息流的实际传递效果未能达到理想状态的原因,采用文献调查、理论分析等方法,对BIM工程信息流的噪声因素进行梳理,并得到了13个主要噪声因素。将13个噪声因素,利用系统动力学软件Vensim进行BIM工程信息流系统的仿真,对其中的关键因素进行辨析。通过研究得出:政府要求及政策支持度、业主利益分配合理度以及BIM规范的统一性对系统影响较大;施工类BIM软件成熟度对系统的影响比设计类BIM软件成熟度影响大等相关结论,并从中得到启示。本研究有助于BIM应用效益的实现,推动BIM的进一步发展。
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60904068,10902076,11072117,and 61004113)
文摘In this paper, the lattice model is presented, incorporating not only site information about preceding cars but also relative currents in front. We derive the stability condition of the extended model by considering a small perturbation around the homogeneous flow solution and find that the improvement in the stability of traffic flow is obtained by taking into account preceding mixture traffic information. Direct simulations also confirm that the traffic jam can be suppressed efficiently by considering the relative currents ahead, just like incorporating site information in front. Moreover, from the nonlinear analysis of the extended models, the preceding mixture traffic information dependence of the propagating kink solutions for traffic jams is obtained by deriving the modified KdV equation near the critical point using the reductive perturbation method.
文摘在现代反导作战中,如何规划反导作战指控系统从而缩短目标、指挥信息传输时间和提高指挥精度是很重要的问题。基于此展开讨论,首先设计规划了3种反导作战指控系统信息流时延模型并提出了应用原则,其次分别以一典型3 500 km TBM和不同射程TBM为例进行了时延模型仿真计算和分析,最后通过分析计算结果给出反导作战指控系统建设性结论。
文摘为有效评估反导作战预警信息流转效能,分析了反导预警的作战过程,建立了基于着色Petri网(colored Petri nets,CPN)的反导预警信息流转模型,并用仿真软件对所建立的模型进行了仿真.通过优选效能评估指标,对反导预警信息流转CPN模型进行效能评估和优化.结果分析表明,适当减少用户的数量和传递层级,可以增加信息在用户之间的流转速率,以满足反导预警作战的时效性要求.
