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基于计算机视觉的轨道交通站内火灾检测与定位

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交通运输系统工程与信息 2024年第3期24卷 53-63页

作者：张金雷杨健刘晓冰陈瑶杨立兴高自友北京交通大学系统科学学院北京100044 北京交通大学交通运输学院北京100044

为及时有效地处理轨道交通站内火灾事件,本文提出基于计算机视觉的站内火灾检测与精细化火灾定位模型(Fire-Detect)。首先,基于Unity仿真模拟和收集互联网图像数据的方式制作站内火灾图像与视频数据集Fire-Rail,用于训练构建的火灾检测... 详细信息

为及时有效地处理轨道交通站内火灾事件,本文提出基于计算机视觉的站内火灾检测与精细化火灾定位模型(Fire-Detect)。首先,基于Unity仿真模拟和收集互联网图像数据的方式制作站内火灾图像与视频数据集Fire-Rail,用于训练构建的火灾检测算法和精细化火灾定位算法;其次,基于卷积神经网络、残差结构与通道注意力机制构建火灾检测算法,用于检测站内监控视频中每帧分别为“正常状态”或“疑似火灾”状态;最后,在“疑似火灾”状态下,模型启动精细化火灾定位算法,将图像以及后续的每帧图像输入精细化火灾定位算法中,并实时输出火灾发生场景下的精细化火灾定位信息。在Fire-Rail数据集上进行实验,火灾检测算法在测试集的准确率为95.12%;此外,卷积神经网络层级实验平衡了资源消耗和准确率,消融实验验证了各部分的有效性,鲁棒性实验表明,该算法能处理大部分噪声,整体模型的平均火灾定位检测精度mAP为77.3%,可应用于轨道交通站内视频监控设备。

关键词：智能交通火灾检测深度学习轨道交通车站计算机视觉

TWO-WAY ROAD NETWORK DESIGN PROBLEM WITH VARIABLE LANES

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Journal of Systems Science and Systems Engineering 2007年第1期16卷 50-61页

作者： Haozhi ZHANG ziyou gao School of Traffic and Transportation Beijing Jiaotong University Beijing 100044 China

This paper studies a new form of transportation network design problem. In urban transportation network, unreasonable phenomenon can occur in certain traffic period （e.g. on/off duty period）, which demonstrates that the flows of opposite directions on a two-way road are seriously asymmetric; one traffic link of a two-way road congest heavily but the other is hardly used. In order to reduce transportation congestion and make full use of the existing road resources, we propose a lane reallocating approach in peak period, and establish a discrete hi-level programming model for the decision-making. Then, based on particle swarm optimization （PSO） technique, a heuristic solution algorithm for the hi-level model is designed. Finally, the lane reallocating approach is demonstrated through a simple transportation network.

关键词： transportation network design problem lane reallocating hi-level programming particle swarm optimization

AN IMPROVED ALGORITHM FOR SOLVING ALL D-MPS IN MULTI-STATE NETWORKS

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Journal of Systems Science and Systems Engineering 2017年第6期26卷 711-731页

作者： Niu, Yifeng gao, ziyou Sun, Huijun School of Mathematics and Information Science Henan Polytechnic University Jiaozuo China School of Traffic and Transportation Beijing Jiaotong University Beijing China

Reliability is a desirable performance indicator of many real-world systems to measure the quality level. One general method for evaluating multi-state reliability is using d-minimal paths （d-MPs）. However, being an NP-hard problem, searching for all d-MPs is a rather challenging task. This paper proposes an improved algorithm to solve the d-MP problem. To reduce the search space of d-MPs, a concept of lower capacity bound is introduced into the d-MP problem, and an effective technique is developed to fred lower capacity bounds. Meanwhile, the fast enumeration method which is a recent improvement to the traditional enunaeration method is employed to solve d-MPs. In addition, by introducing the operation of transforming undirected edges into directed edges, the proposed algorithm is applicable to solving both directed networks and undirected networks. Through numerical experiments, it is found that the proposed algorithm holds a distinct advantage over the existing methods in solving all d-MPs.

关键词： Reliability multi-state network d-minimal paths state vector

A complementary formulation for traffic equilibrium problem with a new nonadditive route cost

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Science China(Technological Sciences) 2011年第9期54卷 2525-2530页

作者： XU Meng gao ziyou MOE Key Laboratory for Urban Transportation Complex Systems Theory and Technology Beijing Jiaotong University Beijing 100044 China Institute of Systems Science School of Traffic and Transportation Beijing Jiaotong University Beijing 100044 China

Improviag transportation system is essential for all people in each city since transport plays a very important role. Using mathematical programming approach transport problem is an effective way to improve transportation system. In this paper, the traffic equilibrium problem （TEP） with a general nonadditive route cost function is studied. We formulate the route cost function for each route as a disutility function, which can evaluate route cost function flexibly and analyze the route toll conveniently. Furthermore, we present the TEP with a nonlinear complementary problem （NCP） formulation. The monotonicity and the existence with the NCP formulation are also given under relative assumptions.

关键词： traffic equilibrium problem nonadditive cost nonlinear complementarity problem

Continuum modeling for two-lane traffic flow

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Acta Mechanica Sinica 2006年第2期22卷 132-137页

作者： Haijun Huang Tieqiao Tang ziyou gao School of Management Beijing University of Aeronautics & stronautics Beijing 100083 China School of Traffic and Transportation Beijing Jiaotong University Beijing 100044 China

In this paper, we study the continuum modeling of traffic dynamics for two-lane freeways. A new dynamics model is proposed, which contains the speed gradient-based momentum equations derived from a car-following theory suited to two-lane traffic flow. The conditions for securing the linear stability of the new model are presented. Numerical tests are can＇ied out and some nonequilibrium phenomena are observed, such as small disturbance instability, stop-and-go waves, local clusters and phase transition.

关键词： Traffic dynamics Two-lane traffic flow Car-following theory Momentum equation

Topological-based bottleneck analysis and improvement strategies for traffic networks

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Science China(Technological Sciences) 2009年第10期52卷 2814-2822页

作者： JianJun Wu ziyou gao HuiJun Sun State Key Laboratory of Rail Traffic Control and Safety (Beijing Jiaotong University) Beijing 100044 China School of Traffic and Transportation Beijing Jiaotong University Beijing 100044 China MOE Key Laboratory for Urban Transportation Complex Systems Theory and Technology Beijing Jiaotong University Beijing 100044 China

A method is proposed to find key components of traffic networks with homogenous and heterogeneous topologies, in which heavier traffic flow is transported. One component, called the skeleton, is the minimum spanning tree (MST) based on the zero flow cost (ZCMST). The other component is the infinite incipient percolation cluster (IIC) which represents the spine of the traffic network. Then, a new method to analysis the property of the bottleneck in a large scale traffic network is given from a macroscopic and statistical viewpoint. Moreover, three effective strategies are proposed to alleviate traffic congestion. The significance of the findings is that one can significantly improve the global transport by enhancing the capacity in the ZCMST with a few links, while for improving the local traffic property, improving a tiny fraction of the traffic network in the IIC is effective. The result can be used to help traffic managers prevent and alleviate traffic congestion in time, guard against the formation of congestion bottleneck, and make appropriate policies for traffic demand management. Meanwhile, the method has very important theoretical significance and practical worthiness in optimizing traffic organization, traffic control, and disposal of emergency.

关键词： traffic congestion user equilibrium assignment heterogeneous and homogenous networks

Impacts of variable message signs on traffic congestion

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Science China(Technological Sciences) 2009年第2期52卷 477-483页

作者： SHANG HuaYan HUANG HaiJun gao ziyou School of Economics and Management Beihang UniversityBeijing 100083China School of Traffic and Transportation Beijing Jiaotong UniversityBeijing 100044China

The variable message signs (VMS) have been widely used in guiding and managing the dynamic traffic with development of intelligent transportation technologies. It is known that cell transmission model (CTM) can well reproduce such traffic dynamics as shock waves and jams. This paper presents a new method to estimate the route travel times by using the CTM in conjunction with a logit-based route choice rule. The impacts of VMS on a two-route scenario with recurrent and non-recurrent traffic congestion are numerically investigated by analyzing the changes of route flow and travel time. Simulation results show that in networks with suitable long links, the VMS can positively influence travelers' decision making so as to improve the system performance. For non-recurrent congestion, the value space of the route choice parameter that affects the flow distribution between two routes is narrower in the case of high traffic demand than that in the low demand case.

关键词： variable message signs cell transmission model traffic congestion numerical simulation

CHARGING STATION PLANNING FOR PLUG-IN ELECTRIC VEHICLES

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Journal of Systems Science and Systems Engineering 2018年第1期27卷 24-45页

作者： Zhihong Zhu ziyou gao Jianfeng Zheng Haoming Du Transportation Management College Dalian Maritime University Dalian China

A novel model for the charging station planning problem of plug-in electric vehicles is proposed in this paper considering the users＇ daily travel. With the objective of minimizing the total cost, including the charging stations＇ cost （including installing cost and management cost） and the users＇ cost （including station access cost and charging cost）, the proposed model simultaneously handles the problems where to locate the charging stations and how many chargers to be established in each charging station. Considering that different users may have different perception of station access cost and charging cost, two cases （i.e., homogeneous users and heterogeneous users） are typically investigated. The impacts of different discount rates, operating period of the charging stations, number of electric vehicles and number of charging stations on the location of the charging station are also studied. The simulation results not only show that it is very important to locate the charging stations according to the traveling behavior of users, but also verify the validity of the proposed model.

关键词： Electric vehicles charging station location problem

Car capacity near bus stops with mixed traffic derived by additive-conflict-flows procedure

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Science China(Technological Sciences) 2011年第3期54卷 733-740页

作者： YANG XiaoBao gao ziyou SI BingFeng gao Liang MOE Key Laboratory for Urban Transportation Complex Systems Theory and Technology Beijing Jiaotong University Beijing 100044 China

To determinate car capacity at bus stops with mixed traffic, a new theoretical approach was developed on the basis of additive-conflict-flows procedure. The procedure was extended from homogeneous traffic flow to mixed traffic flow. The conflicts among cars, buses and bicycles near the stop can be described by the extended procedure. The procedure can be understood more easily than the theory of gap acceptance. Car capacity near the stop is the function of both bus stream and bicycle stream. The proposed model can also analyze the cases of pedestrian effects and limited priority of bicyclists. Numerical results show that the car capacity decreases with the increasing flow rates of other streams. In addition, pedestrian effects and bicyclist's limited priority have negative effects on car capacity near bus stops with mixed traffic flow.

关键词： road capacity bus stop additive-conflict-flows procedure mixed traffic flow