在大型异构路网中,不同区域的交通运行特征存在显著差异,因此需要针对各个区域的具体特征制定相应的交通管理和控制策略。合理划分路网以获得交通特征均质的子区,对于有效的交通管控和分析至关重要。首先提出了一种改进的密度峰值聚类方...在大型异构路网中,不同区域的交通运行特征存在显著差异,因此需要针对各个区域的具体特征制定相应的交通管理和控制策略。合理划分路网以获得交通特征均质的子区,对于有效的交通管控和分析至关重要。首先提出了一种改进的密度峰值聚类方法(Enhanced Density Peak Clustering,En-DPC),用于路网子区的初始划分。该方法基于质量概率相似性并考虑路网连接性约束,提升了算法对异常数据的鲁棒性,避免子区内路段不连续的问题。接着,利用En-DPC方法对初始划分的子区进一步合并,形成大小适中的新子区。最后,通过边界调整提高子区边界的平滑度,获得最终的划分结果。该方法能够根据路网交通状态自动确定子区数量,确保划分的合理性。此外,考虑到路网拥堵状态的时空演变,在静态划分基础上设计了一种动态划分方法,根据车辆密度的变化动态调整边界,以提升其在实时交通管控中的适用性,并利用瑞士苏黎世的线圈检测器数据验证了所提出方法的有效性。结果表明,本文提出的方法能够有效地将大型异构路网划分成均质子区,且每个子区都可获得一个清晰的宏观基本图。与现有文献中的路网划分方法如归一分割和“蛇”方法相比,本文方法不仅在归一化总方差、平均NcutSilhouette和模块度等性能评价指标上表现更优,而且子区划分时间明显低于其他两种方法。展开更多
Community division is an important method to study the characteristics of complex networks.The widely used fast-Newman(FN)algorithm only considers the topology division of the network at the static layer,and dynamic t...Community division is an important method to study the characteristics of complex networks.The widely used fast-Newman(FN)algorithm only considers the topology division of the network at the static layer,and dynamic traffic flow demand is ignored.The result of the division is only structurally optimal.To improve the accuracy of community division,based on the static topology of air route network,the concept of network traffic contribution degree is put forward.The concept of operational research is introduced to optimize the network adjacency matrix to form an improved community division algorithm.The air route network in East China is selected as the object of algorithm comparison experiment,including 352 waypoints and 928 segments.The results show that the improved algorithm has a more ideal effect on the division of the community structure.The proportion of the number of nodes included in the large community has increased by 21.3%,and the modularity value has increased from 0.756 to 0.806,in which the modularity value is in the range of[-0.5,1).The research results can provide theoretical and technical support for the optimization of flight schedules and the rational use of air route resources.展开更多
In order to form an algorithm for distribution network routing,an automatic routing method of distribution network planning was proposed based on the shortest path.The problem of automatic routing was divided into two...In order to form an algorithm for distribution network routing,an automatic routing method of distribution network planning was proposed based on the shortest path.The problem of automatic routing was divided into two steps in the method:the first step was that the shortest paths along streets between substation and load points were found by the basic ant colony algorithm to form a preliminary radial distribution network,and the second step was that the result of the shortest path was used to initialize pheromone concentration and pheromone updating rules to generate globally optimal distribution network.Cases studies show that the proposed method is effective and can meet the planning requirements.It is verified that the proposed method has better solution and utility than planning method based on the ant colony algorithm.展开更多
本文针对路网密度分布的空间异质性会导致宏观基本图(Macroscopic Fundamental Diagram,MFD)高度离散的问题,提出了一种将异质性城市路网划分为同质子路网的方法。利用张量分解算法提取路段交通状态在时间维度上的短期日变化和长期逐日...本文针对路网密度分布的空间异质性会导致宏观基本图(Macroscopic Fundamental Diagram,MFD)高度离散的问题,提出了一种将异质性城市路网划分为同质子路网的方法。利用张量分解算法提取路段交通状态在时间维度上的短期日变化和长期逐日变化特征,以此计算路段间相似度。以路段间相似度为边权,针对含权的城市道路交通网络改进传统的Fast-Newman快速划分算法,来保证划分后每个子路网内的路段交通状态相似且在空间上紧密分布。基于某市一个月的自动车牌识别数据对该方法进行实证分析,结果表明改进算法划分效果优于K-means算法及传统Fast-Newman快速划分算法,划分后每个子路网的MFD函数关系都有较好的拟合效果,子路网之间的交通流特征参数差异明显。展开更多
文摘在大型异构路网中,不同区域的交通运行特征存在显著差异,因此需要针对各个区域的具体特征制定相应的交通管理和控制策略。合理划分路网以获得交通特征均质的子区,对于有效的交通管控和分析至关重要。首先提出了一种改进的密度峰值聚类方法(Enhanced Density Peak Clustering,En-DPC),用于路网子区的初始划分。该方法基于质量概率相似性并考虑路网连接性约束,提升了算法对异常数据的鲁棒性,避免子区内路段不连续的问题。接着,利用En-DPC方法对初始划分的子区进一步合并,形成大小适中的新子区。最后,通过边界调整提高子区边界的平滑度,获得最终的划分结果。该方法能够根据路网交通状态自动确定子区数量,确保划分的合理性。此外,考虑到路网拥堵状态的时空演变,在静态划分基础上设计了一种动态划分方法,根据车辆密度的变化动态调整边界,以提升其在实时交通管控中的适用性,并利用瑞士苏黎世的线圈检测器数据验证了所提出方法的有效性。结果表明,本文提出的方法能够有效地将大型异构路网划分成均质子区,且每个子区都可获得一个清晰的宏观基本图。与现有文献中的路网划分方法如归一分割和“蛇”方法相比,本文方法不仅在归一化总方差、平均NcutSilhouette和模块度等性能评价指标上表现更优,而且子区划分时间明显低于其他两种方法。
基金the Fundamental Research Funds for the Central Universities,and the Foundation of Graduate Innovation Center in NUAA(No.kfjj20190735)。
文摘Community division is an important method to study the characteristics of complex networks.The widely used fast-Newman(FN)algorithm only considers the topology division of the network at the static layer,and dynamic traffic flow demand is ignored.The result of the division is only structurally optimal.To improve the accuracy of community division,based on the static topology of air route network,the concept of network traffic contribution degree is put forward.The concept of operational research is introduced to optimize the network adjacency matrix to form an improved community division algorithm.The air route network in East China is selected as the object of algorithm comparison experiment,including 352 waypoints and 928 segments.The results show that the improved algorithm has a more ideal effect on the division of the community structure.The proportion of the number of nodes included in the large community has increased by 21.3%,and the modularity value has increased from 0.756 to 0.806,in which the modularity value is in the range of[-0.5,1).The research results can provide theoretical and technical support for the optimization of flight schedules and the rational use of air route resources.
基金Project(2009CB219703) supported by the National Basic Research Program of ChinaProject(2011AA05A117) supported by the National High Technology Research and Development Program of China
文摘In order to form an algorithm for distribution network routing,an automatic routing method of distribution network planning was proposed based on the shortest path.The problem of automatic routing was divided into two steps in the method:the first step was that the shortest paths along streets between substation and load points were found by the basic ant colony algorithm to form a preliminary radial distribution network,and the second step was that the result of the shortest path was used to initialize pheromone concentration and pheromone updating rules to generate globally optimal distribution network.Cases studies show that the proposed method is effective and can meet the planning requirements.It is verified that the proposed method has better solution and utility than planning method based on the ant colony algorithm.
文摘本文针对路网密度分布的空间异质性会导致宏观基本图(Macroscopic Fundamental Diagram,MFD)高度离散的问题,提出了一种将异质性城市路网划分为同质子路网的方法。利用张量分解算法提取路段交通状态在时间维度上的短期日变化和长期逐日变化特征,以此计算路段间相似度。以路段间相似度为边权,针对含权的城市道路交通网络改进传统的Fast-Newman快速划分算法,来保证划分后每个子路网内的路段交通状态相似且在空间上紧密分布。基于某市一个月的自动车牌识别数据对该方法进行实证分析,结果表明改进算法划分效果优于K-means算法及传统Fast-Newman快速划分算法,划分后每个子路网的MFD函数关系都有较好的拟合效果,子路网之间的交通流特征参数差异明显。
