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A New System for Road Traffic Optimisation Using the Virtual Traffic Light Technology
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作者 Ahmad A.A.Alkhatib Adnan A.Hnaif Thaer Sawalha 《Computer Systems Science & Engineering》 SCIE EI 2023年第10期637-656,共20页
Large cities suffer from traffic congestion,particularly at intersections,due to a large number of vehicles,which leads to the loss of time by increasing carbon emissions,including fuel consumption.Therefore,the need ... Large cities suffer from traffic congestion,particularly at intersections,due to a large number of vehicles,which leads to the loss of time by increasing carbon emissions,including fuel consumption.Therefore,the need for optimising the flow of vehicles at different intersections and reducing the waiting time is a critical challenge.Conventional traffic lights have been used to control traffic flow at different intersections and have been improved to become more efficient by using different algorithms,sensors and cameras.However,they also face some challenges,such as high-cost installation,operation,and maintenance issues.This paper develops a new system based on the Virtual Traffic Light(VTL)technology to improve traffic flow at different intersections and reduce the encountered loss of time and vehicles’travel time.Additionally,it reduces the costs of installation,maintenance and operation over various conventional traffic light systems.Consequently,the system proposes algorithms for traffic scheduling and lane identification by using vehicle ID,priority and time of arrival.To evaluate the system,four scenarios were presented where each scenario uses a different number of vehicles consisting of three types(emergency vehicles,public buses and private vehicles),each given a different priority.The proposed system is evaluated by integrating two simulators,namely,(OMNeT++)and(SUMO),and two frameworks,namely,(VEINS)and(INET)to prepare an appropriate working environment.the results prove that an improvement in the average travel time for several vehicles reaches 44.43%–49.76%compared with conventional traffic lights.Further,it is proven from the obtained results that the average waiting time for emergency vehicles is enhanced by 96.63%–97.63%,while the average waiting time for public buses is improved by 94.81%–97.23%.On the other hand,the waiting time for private vehicles‘improved by 87.14%to 89.71%’. 展开更多
关键词 Virtual traffic lights(VTL) vehicle-to-roadside unit(V2R) RSU smart vehicles(SV) intelligent traffic system(ITS)
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Intelligent 3-Way Priority-Driven Traffic Light Control System for Emergency Vehicles
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作者 Joe Essien Felix Uloko 《Open Journal of Applied Sciences》 2023年第8期1207-1223,共17页
The problem of traffic congestion is a significant phenomenon that has had a substantial impact on the transportation system within the country. This phenomenon has given rise to numerous intricacies, particularly in ... The problem of traffic congestion is a significant phenomenon that has had a substantial impact on the transportation system within the country. This phenomenon has given rise to numerous intricacies, particularly in instances where emergency situations occur at traffic light intersections that are consistently congested with a high volume of vehicles. This implementation of a traffic light controller system is designed with the intention of addressing this problem. The purpose of the system was to facilitate the operation of a 3-way traffic control light and provide priority to emergency vehicles using a Radio Frequency Identification (RFID) sensor and Reduced Instruction Set Computing (RISC) Architecture Based Microcontroller. This research work involved designing a system to mitigate the occurrence of accidents commonly observed at traffic light intersections, where vehicles often need to maneuver in order to make way for emergency vehicles following a designated route. The research effectively achieved the analysis, simulation and implementation of wireless communication devices for traffic light control. The implemented prototype utilizes RFID transmission, operates in conjunction with the sequential mode of traffic lights to alter the traffic light sequence accordingly and reverts the traffic lights back to their normal sequence after the emergency vehicle has passed the traffic lights. 展开更多
关键词 RFID Sensors MICROCONTROLLER traffic light Control system RISC Architecture Intelligent systems
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Design and Analysis of Traffic Information Transmission System Based on Visible Light Communication 被引量:1
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作者 Wei Wang Hui-Fang Liu +2 位作者 Ning Wang Zhao Hui Chi Song 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第5期57-61,共5页
Visible Light Communication( VLC) based on LED is a new wireless communication technology with high response rate and good modulation characteristics in the wavelengths of 380- 780 nm. Compared with conventional metho... Visible Light Communication( VLC) based on LED is a new wireless communication technology with high response rate and good modulation characteristics in the wavelengths of 380- 780 nm. Compared with conventional methods,the waveband of VLC is harmless to human and safe to communication because of no magnetism radiation. An audio information transmission system using LED traffic lights is presented based on VLC technology. The system is consisted of transmitting terminal,receiving terminal and communication channel. Some experiments were made under real communication environment. The experimental results showed that the traffic information transmission system works steadily with good communication quality and achieves the purpose of transmitting audio information through LED traffic lights,with a data transfer rate up to 250 kbps over a distance of 5 meters. 展开更多
关键词 LED traffic lights Visible light Communication(VLC) Audio Information Transmission Intelligent Transport system(ITS)
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基于图神经网络的SSL/TLS加密恶意流量检测算法研究
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作者 唐瑛 王宝会 《计算机科学》 CSCD 北大核心 2024年第9期365-370,共6页
为实现SSL/TLS加密恶意流量的精准检测,针对传统机器学习方法过分依赖专家经验的问题,提出一种基于图神经网络的恶意加密流量检测模型。通过对SSL/TLS加密会话进行分析,利用图结构对流量会话交互信息进行表征,将恶意加密流量检测问题转... 为实现SSL/TLS加密恶意流量的精准检测,针对传统机器学习方法过分依赖专家经验的问题,提出一种基于图神经网络的恶意加密流量检测模型。通过对SSL/TLS加密会话进行分析,利用图结构对流量会话交互信息进行表征,将恶意加密流量检测问题转化为图分类问题。生成的模型基于分层图池化架构,通过多层卷积池化的聚合,结合注意力机制,充分挖掘图中节点特征和图结构信息,实现了端到端的恶意加密流量检测方法。基于公开数据集CICAndMal2017进行验证,实验结果表明,所提模型在加密恶意流量二分类检测中,准确率高达97.1%,相较于其他模型,准确率、召回率、精确率、F1分数分别提升了2.1%,3.2%,1.6%,2.1%,说明所提方法对于恶意加密流量的表征能力和检测能力优于其他方法。 展开更多
关键词 SSL/tls 恶意加密流量 图神经网络 图分类 分层池化
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A Workable Solution for Reducing the Large Number of Vehicle and Pedestrian Accidents Occurring on a Yellow Light
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作者 Pranav Gupta Silki Arora 《Journal of Transportation Technologies》 2024年第1期82-87,共6页
Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada... Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada, during 2019, the National Collision Database shows that 28% of traffic fatalities and 42% of serious injuries occurred at intersections. Likewise, the U.S. National Highway Traffic Administration (NHTSA) found that about 40% of the estimated 5,811,000 accidents in the U.S. during the year studied were intersection-related crashes. In fact, a major survey by the car insurance industry found that nearly 85% of drivers could not identify the correct action to take when approaching a yellow traffic light at an intersection. One major reason for these accidents is the “yellow light dilemma,” the ambiguous situation where a driver should stop or proceed forward when unexpectedly faced with a yellow light. This situation is even further exacerbated by the tendency of aggressive drivers to inappropriately speed up on the yellow just to get through the traffic light. A survey of Canadian drivers conducted by the Traffic Injury Research Foundation found that 9% of drivers admitted to speeding up to get through a traffic light. Another reason for these accidents is the increased danger of making a left-hand turn on yellow. According to the National Highway Traffic Safety Association (NHTSA), left turns occur in approximately 22.2% of collisions—as opposed to just 1.2% for right turns. Moreover, a study by CNN found left turns are three times as likely to kill pedestrians than right turns. The reason left turns are so much more likely to cause an accident is because they take a driver against traffic and in the path of oncoming cars. Additionally, most of these left turns occur at the driver’s discretion—as opposed to the distressingly brief left-hand arrow at busy intersections. Drive Safe Now proposes a workable solution for reducing the number of accidents occurring during a yellow light at intersections. We believe this fairly simple solution will save lives, prevent injuries, reduce damage to public and private property, and decrease insurance costs. 展开更多
关键词 traffic Accidents Yellow light traffic light Signals INTERSECTION Crashes Collision traffic Fatalities traffic Injuries Vehicles SAFETY Speed Limit Driving Pedestrians Bicyclists MOTORCYCLISTS Caution Line Yellow light Dilemma Left Hand Turn on Yellow Distance Smart Road Technology Signs Signage Autonomous Vehicles AVs Road Safety IoT Internet of Things Infrastructure Accident Reduction Driving Habits Stop Line Red light Jumping Pedestrian Safety Caution light Stopping at Intersection Safety at Intersections
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Optimal traffic light control method for a single intersecti on basedon hybrid systems
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作者 赵晓华 陈阳舟 崔平远 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第4期453-456,共4页
A single intersection of two phases is selected as a model to put forward a new optimal time-planning scheme for traffic light based on the model of hybrid automata for single intersection. A method of optimization is... A single intersection of two phases is selected as a model to put forward a new optimal time-planning scheme for traffic light based on the model of hybrid automata for single intersection. A method of optimization is proposed for hybrid systems, and the average queue length over all queues is used as an objective function to find an optimal switching scheme for traffic light. It is illustrated that traffic light control for single intersection is a typical hybrid system, and the optimal planning-time scheme can be obtained using the optimal hybrid systems control based on the two stages method. 展开更多
关键词 hybrid systems theory optimal control of hybrid systems traffic light control optimal time-planning
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Effectiveness of traffic light system on Brazilian consumers perception of food healthfulness
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作者 Mayara Lima Marcela de Alcantara +1 位作者 Amauri Rosenthal Rosires Deliza 《Food Science and Human Wellness》 SCIE 2019年第4期368-374,共7页
Front-of-package(FOP)nutrition labelling schemes were developed to improve consumer’s comprehension about the food nutrients associated with non-communicable diseases(NCDs).Several FOPs have already been developed,an... Front-of-package(FOP)nutrition labelling schemes were developed to improve consumer’s comprehension about the food nutrients associated with non-communicable diseases(NCDs).Several FOPs have already been developed,and Brazil is in the process of evaluating a scheme to introduce in the products.The aim of this study was to investigate the impact of TLS,the scheme proposed by the food industry,on the product healthfulness perception.A study with 141 participants was carried out.A conjoint task was designed considering three categories and levels:types of dairy products(light yogurt,prato cheese,and chocolate flavoured milk),Traffic Light System(yes vs.no)and brand(well-known vs.unknown).The effect of TLS on perceived healthfulness was evaluated using a 9-point scales(1:not healthy;9:very healthy).Results showed that the inclusion of TLS did not influence the perceived healthfulness of the products by consumers,even among consumers with higher interest in healthy eating.These findings suggest that the proposal supported by the food industry does not seem to be the most appropriate,being recommended the development of further studies to compare the efficacy of TLS and other FOP schemes. 展开更多
关键词 Front of pack traffic light system Healthfulness perception Food products
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针对TLS恶意流量问题的检测和分类研究
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作者 狄巨星 张文成 +1 位作者 杨阳 冯方涛 《福建电脑》 2024年第2期70-72,共3页
随着加密流量的快速增长,通过传统机器学习方法来对恶意TLS流量的识别与分类效果不好。为提高对恶意流量的识别效率,本文提出一种改进卷积神经网络与长短期记忆网络结合的恶意流量检测方法。实验结果显示,该方法在识别恶意TLS流量上的... 随着加密流量的快速增长,通过传统机器学习方法来对恶意TLS流量的识别与分类效果不好。为提高对恶意流量的识别效率,本文提出一种改进卷积神经网络与长短期记忆网络结合的恶意流量检测方法。实验结果显示,该方法在识别恶意TLS流量上的二分类的F1值为93.4,在多分类实验上平均准确率为84.87,具有较好的检测和分类效果。 展开更多
关键词 恶意tls流量检测 卷积神经网络 长短期记忆网络
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Neural Network-Powered License Plate Recognition System Design
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作者 Sakib Hasan Md Nagib Mahfuz Sunny +1 位作者 Abdullah Al Nahian Mohammad Yasin 《Engineering(科研)》 2024年第9期284-300,共17页
The development of scientific inquiry and research has yielded numerous benefits in the realm of intelligent traffic control systems, particularly in the realm of automatic license plate recognition for vehicles. The ... The development of scientific inquiry and research has yielded numerous benefits in the realm of intelligent traffic control systems, particularly in the realm of automatic license plate recognition for vehicles. The design of license plate recognition algorithms has undergone digitalization through the utilization of neural networks. In contemporary times, there is a growing demand for vehicle surveillance due to the need for efficient vehicle processing and traffic management. The design, development, and implementation of a license plate recognition system hold significant social, economic, and academic importance. The study aims to present contemporary methodologies and empirical findings pertaining to automated license plate recognition. The primary focus of the automatic license plate recognition algorithm was on image extraction, character segmentation, and recognition. The task of character segmentation has been identified as the most challenging function based on my observations. The license plate recognition project that we designed demonstrated the effectiveness of this method across various observed conditions. Particularly in low-light environments, such as during periods of limited illumination or inclement weather characterized by precipitation. The method has been subjected to testing using a sample size of fifty images, resulting in a 100% accuracy rate. The findings of this study demonstrate the project’s ability to effectively determine the optimal outcomes of simulations. 展开更多
关键词 Intelligent traffic Control systems Automatic License Plate Recognition (ALPR) Neural Networks Vehicle Surveillance traffic Management License Plate Recognition Algorithms Image Extraction Character Segmentation Character Recognition Low-light Environments Inclement Weather Empirical Findings Algorithm Accuracy Simulation Outcomes DIGITALIZATION
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Traffic light detection and recognition in intersections based on intelligent vehicle
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作者 张宁 何铁军 +1 位作者 高朝晖 黄卫 《Journal of Southeast University(English Edition)》 EI CAS 2008年第4期517-521,共5页
To ensure revulsive driving of intelligent vehicles at intersections, a method is presented to detect and recognize the traffic lights. First, the stabling siding at intersections is detected by applying Hough transfo... To ensure revulsive driving of intelligent vehicles at intersections, a method is presented to detect and recognize the traffic lights. First, the stabling siding at intersections is detected by applying Hough transformation. Then, the colors of traffic lights are detected with color space transformation. Finally, self-associative memory is used to recognize the countdown characters of the traffic lights. Test results at 20 real intersections show that the ratio of correct stabling siding recognition reaches up to 90%;and the ratios of recognition of traffic lights and divided characters are 85% and 97%, respectively. The research proves that the method is efficient for the detection of stabling siding and is robust enough to recognize the characters from images with noise and broken edges. 展开更多
关键词 intelligent vehicle stabling siding detection traffic lights detection self-associative memory light-emitting diode (LED) characters recognition
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Simulation of traffic flow with traffic light strategies via a modified cellular automaton model 被引量:1
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作者 何红弟 董力耘 戴世强 《Journal of Shanghai University(English Edition)》 CAS 2006年第3期189-191,共3页
Traffic flows controlled by traffic light strategies were investigated via a cellular automaton model with anticipation, which is suitable for describing urban traffic. Three kinds of strategies, i. e., synchronized, ... Traffic flows controlled by traffic light strategies were investigated via a cellular automaton model with anticipation, which is suitable for describing urban traffic. Three kinds of strategies, i. e., synchronized, green-wave and random switching lights, were designed, simulated and compared with each other. It is shown that the green-wave strategy is only valid at lower density and there is not an effective way with the three strategies to improve the efficiency of traffic flow at high density. 展开更多
关键词 traffic flow cellular automaton model trafflc light strategy.
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A Greedy Traffic Light and Queue Aware Routing Protocol for Urban VANETs 被引量:2
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作者 Yangyang Xia Xiaoqi Qin +1 位作者 Baoling Liu Ping Zhang 《China Communications》 SCIE CSCD 2018年第7期77-87,共11页
Vehicular Ad-hoc Networks(VANETs) require reliable data dissemination for time-sensitive public safety applications. An efficient routing protocol plays a vital role to achieve satisfactory network performance. It is ... Vehicular Ad-hoc Networks(VANETs) require reliable data dissemination for time-sensitive public safety applications. An efficient routing protocol plays a vital role to achieve satisfactory network performance. It is well known that routing is a challenging problem in VANETs due to the fast-changing network typology caused by high mobility at both ends of transmission. Moreover, under urban environment, there are two non-negligible factors in routing protocol design, the non-uniform vehicle distribution caused by traffic lights, and the network congestion due to high traffic demand in rush hours. In this paper, we propose a greedy traffic light and queue aware routing protocol(GTLQR) which jointly considers the street connectivity, channel quality, relative distance, and queuing delay to alleviate the packet loss caused by vehicle clustering at the intersection and balance the traffic load among vehicles. Through performance evaluation, we show that our proposed protocol outperforms both TLRC and GLSR-L in terms of packet delivery ratio and end-to-end delay. 展开更多
关键词 VANETS 5G traffic light queuing delay vehicular communications
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Safer Design and Less Cost Operation for Low-Traffic Long-Road Illumination Using Control System Based on Pattern Recognition Technique 被引量:1
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作者 Muhammad M. A. S. Mahmoud Leyla Muradkhanli 《Intelligent Control and Automation》 2020年第3期47-62,共16页
The paper covers analysis and investigation of lighting automation system in low-traffic long-roads. The main objective is to provide optimal solution between expensive safe design that utilizes continuous street ligh... The paper covers analysis and investigation of lighting automation system in low-traffic long-roads. The main objective is to provide optimal solution between expensive safe design that utilizes continuous street lighting system at night for the entire road, or inexpensive design that sacrifices the safety, relying on using vehicles lighting, to eliminate the problem of high cost energy consumption during the night operation of the road. By taking into account both of these factors, smart lighting automation system is proposed using Pattern Recognition Technique applied on vehicle number-plates. In this proposal, the road is sectionalized into zones, and based on smart Pattern Recognition Technique, the control system of the road lighting illuminates only the zone that the vehicles pass through. Economic analysis is provided in this paper to support the value of using this design of lighting control system. 展开更多
关键词 Road lighting Control Road lighting Automation Vehicle Number-Plate Pattern Recognition Smart Grid Power Management Low traffic Roads Image Processing
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Deep Reinforcement Learning for Addressing Disruptions in Traffic Light Control
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作者 Faizan Rasheed Kok-Lim Alvin Yau +1 位作者 Rafidah Md Noor Yung-Wey Chong 《Computers, Materials & Continua》 SCIE EI 2022年第5期2225-2247,共23页
This paper investigates the use of multi-agent deep Q-network(MADQN)to address the curse of dimensionality issue occurred in the traditional multi-agent reinforcement learning(MARL)approach.The proposed MADQN is appli... This paper investigates the use of multi-agent deep Q-network(MADQN)to address the curse of dimensionality issue occurred in the traditional multi-agent reinforcement learning(MARL)approach.The proposed MADQN is applied to traffic light controllers at multiple intersections with busy traffic and traffic disruptions,particularly rainfall.MADQN is based on deep Q-network(DQN),which is an integration of the traditional reinforcement learning(RL)and the newly emerging deep learning(DL)approaches.MADQN enables traffic light controllers to learn,exchange knowledge with neighboring agents,and select optimal joint actions in a collaborative manner.A case study based on a real traffic network is conducted as part of a sustainable urban city project in the Sunway City of Kuala Lumpur in Malaysia.Investigation is also performed using a grid traffic network(GTN)to understand that the proposed scheme is effective in a traditional traffic network.Our proposed scheme is evaluated using two simulation tools,namely Matlab and Simulation of Urban Mobility(SUMO).Our proposed scheme has shown that the cumulative delay of vehicles can be reduced by up to 30%in the simulations. 展开更多
关键词 Artificial intelligence traffic light control traffic disruptions multi-agent deep Q-network deep reinforcement learning
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Advanced Leader Election for Virtual Traffic Lights
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作者 Florian Hagenauer Patrick Baldemaier +1 位作者 Falko Dressler Christoph Sommer 《ZTE Communications》 2014年第1期11-16,共6页
We examine the network performance of algorithms for self-organized traffic management. In particular, we focus on wireless network- ing between cars. One of many technologies that make road traffic safer and more eff... We examine the network performance of algorithms for self-organized traffic management. In particular, we focus on wireless network- ing between cars. One of many technologies that make road traffic safer and more efficient is the Virtual Traffic Light (VTL) system, which is able to coordinate the traffic flow at intersections without the need for physical lights. VTL takes a leading vehicle at an inter- section and uses it to control the traffic lights. We developed algorithms for leader election and traffic light computation in realistic ve- hicular networking scenarios. Our key contribution is the extension of this algorithm to support arbitrary intersection layouts. We in- vestigated the proposal in synthetic and realistic scenarios. The results show that, overall, VTLs use network resources efficiently and positively influences driving experience. It performs better than stationary traffic lights for a low to medium network load. We also identify potential optimizations to deal with high network load and to improve fairness. 展开更多
关键词 virtual traffic lights SELF-ORGANIZATION vehicular networks
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Design of Traffic Light Based on Field Programmable Gate Array
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作者 Lei Zhao 《Journal of Power and Energy Engineering》 2021年第5期93-103,共11页
The use of fixed-time traffic lights for road traffic control has the disadvantage of low traffic efficiency. In order to optimize the vehicle traffic at the intersection, this paper proposes a design scheme of a real... The use of fixed-time traffic lights for road traffic control has the disadvantage of low traffic efficiency. In order to optimize the vehicle traffic at the intersection, this paper proposes a design scheme of a real-time control system for road intelligent traffic lights based on FPGA. The system adopts the polling control model, the vehicle detector detects the arrival rate of vehicles, and obtains the corresponding traffic light green time length according to the traffic rules and polling model theory. Using Altera<span><span><span>’</span></span></span><span><span><span>s Cyclone IV series EP4CE15E22C8 chip as the development platform, a specific design plan is given. The circuit mainly includes program-controlled amplifier module, AD acquisition module, cross-correlation calculation module, serial port transmission and Lab-VIEW module. The system can realize the intelligent adjustment of traffic lights. Different vehicle arrival rates are detected at different times, so that the corresponding traffic light configuration time length changes accordingly. This intelligent adjustment controls road traffic and makes the main and branch roads coordinate and cooperate, thereby improving the traffic efficiency of the intersection.</span></span></span> 展开更多
关键词 FPGA Intelligent traffic lights Clock Division Polling Model
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Basic Limit Theorems for Light Traffic Queues &Their Applications
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作者 Onkabetse A. Daman Sulaiman Sani 《American Journal of Operations Research》 2015年第5期409-420,共12页
In this paper, we study some basic limit theorems characterizing the stationary behavior of light traffic queuing systems. Beginning with limit theorems for the simple M/M/1 queuing system, we demonstrate the methodol... In this paper, we study some basic limit theorems characterizing the stationary behavior of light traffic queuing systems. Beginning with limit theorems for the simple M/M/1 queuing system, we demonstrate the methodology for applying these theorems for the benefit of service systems. The limit theorems studied here are dominant in the literature. Our contribution is primarily on the analysis leading to the application of these theorems in various problem situations for better operations. Relevant Examples are included to aid the application of the results studied in this work. 展开更多
关键词 Queue light traffic QUEUES M/M/C MODEL M/G/C MODEL and OCCUPATION Rates
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A Framework for Agent-Based Traffic Light Control
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作者 Ping Wang 《通讯和计算机(中英文版)》 2013年第5期713-716,共4页
关键词 交通灯控制 Agent 框架 多智能体系统 智能交通控制 代理方式 历史信息 交通拥堵
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Anthropogenic activity,hydrological regime,and light level jointly influence temporal patterns in biosonar activity of the Yangtze finless porpoise at the junction of the Yangtze River and Poyang Lake,China
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作者 Peng-Xiang Duan Zhi-Tao Wang +4 位作者 Tomonari Akamatsu Nick Tregenza Guang-Yu Li Ke-Xiong Wang Ding Wang 《Zoological Research》 SCIE CSCD 2023年第5期919-931,共13页
Under increasing anthropogenic pressure,species with a previously contiguous distribution across their ranges have been reduced to small fragmented populations.The critically endangered Yangtze finless porpoise(Neopho... Under increasing anthropogenic pressure,species with a previously contiguous distribution across their ranges have been reduced to small fragmented populations.The critically endangered Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis),once commonly observed in the Yangtze River-Poyang Lake junction,is now rarely seen in the river-lake corridor.In this study,static passive acoustic monitoring techniques were used to detect the biosonar activities of the Yangtze finless porpoise in this unique corridor.Generalized linear models were used to examine the correlation between these activities and anthropogenic impacts from the COVID-19 pandemic lockdown and boat navigation,as well as environmental variables,including hydrological conditions and light levels.Over approximately three consecutive years of monitoring(2020–2022),porpoise biosonar was detected during 93%of logged days,indicating the key role of the corridor for finless porpoise conservation.In addition,porpoise clicks were recorded in 3.80%of minutes,while feeding correlated buzzes were detected in 1.23%of minutes,suggesting the potential existence of localized,small-scale migration.Furthermore,both anthropogenic and environmental variables were significantly correlated with the diel,lunar,monthly,seasonal,and annual variations in porpoise biosonar activities.During the pandemic lockdown period,porpoise sonar detection showed a significant increase.Furthermore,a significant negative correlation was identified between the detection of porpoise click trains and buzzes and boat traffic intensity.In addition to water level and flux,daylight and moonlight exhibited significant correlations with porpoise biosonar activities,with markedly higher detections at night and quarter moon periods.Ensuring the spatiotemporal reduction of anthropogenic activities,implementing vessel speed restrictions(e.g.,during porpoise migration and feeding),and maintaining local natural hydrological regimes are critical factors for sustaining porpoise population viability. 展开更多
关键词 Yangtze finless porpoises Yangtze River Poyang Lake Pandemic lockdown Boat traffic Hydrological regime light level
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Multi-Objective Optimization of Traffic Signal Timing at Typical Junctions Based on Genetic Algorithms
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作者 Zeyu Zhang Han Zhu +3 位作者 Wei Zhang Zhiming Cai Linkai Zhu Zefeng Li 《Computer Systems Science & Engineering》 SCIE EI 2023年第11期1901-1917,共17页
With the rapid development of urban road traffic and the increasing number of vehicles,how to alleviate traffic congestion is one of the hot issues that need to be urgently addressed in building smart cities.Therefore... With the rapid development of urban road traffic and the increasing number of vehicles,how to alleviate traffic congestion is one of the hot issues that need to be urgently addressed in building smart cities.Therefore,in this paper,a nonlinear multi-objective optimization model of urban intersection signal timing based on a Genetic Algorithm was constructed.Specifically,a typical urban intersection was selected as the research object,and drivers’acceleration habits were taken into account.What’s more,the shortest average delay time,the least average number of stops,and the maximum capacity of the intersection were regarded as the optimization objectives.The optimization results show that compared with the Webster method when the vehicle speed is 60 km/h and the acceleration is 2.5 m/s^(2),the signal intersection timing scheme based on the proposed Genetic Algorithm multi-objective optimization reduces the intersection signal cycle time by 14.6%,the average vehicle delay time by 12.9%,the capacity by 16.2%,and the average number of vehicles stop by 0.4%.To verify the simulation results,the authors imported the optimized timing scheme into the constructed Simulation of the Urban Mobility model.The experimental results show that the authors optimized timing scheme is superior to Webster’s in terms of vehicle average loss time reduction,carbon monoxide emission,particulate matter emission,and vehicle fuel consumption.The research in this paper provides a basis for Genetic algorithms in traffic signal control. 展开更多
关键词 Multi-objective GA optimization traffic light timings average delay time the average number of stops traffic capacity SUMO simulation
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