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Findings on queue length based Macroscopic Fundamental Diagrams with Enhanced Floating Car Estimation Method

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Findings on Queue Length based Macroscopic Fundamental Diagr...

THE queue-length DISTRIBUTION FOR M^x/G/1 queue WITH SINGLE SERVER VACATION

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作者： Junwei Kong Zhongsheng Hou Ye Ren Advanced Control Systems Lab Beijing Jiaotong University

In recent research, the macroscopic fundamental diagram（MFD） has been proved to be a powerful tool for large urban network modelling and control. This paper proposes a novel concept of queue length based MFD（QMFD） considering the fact that queue length is usually regarded as an important index to evaluate the efficiency of intersections. Compared to traditional MFD, the QMFD can reflect the traffic status more intuitively and can be understood more easily by transportation managers and residents. However, the queue length of some links may not be obtained directly in real situations if no fixed detector is available. To solve this problem, this paper proposes a floating car data（FCD） based method to estimate the QMFD. Firstly, a new queue length estimation method is developed by using BP neural network with different floating car percentage. Secondly, based on the estimated queue length, QMFD is calculated by fitting the relationship between the average queue length and other macroscopic traffic parameters such as average flow at intersections. Finally, the proposed method is verified by the traffic data provided by traffic simulation software VISSIM with the real road networks of Beijing’s Second Ring Road. The simulation results demonstrate the effectiveness of the proposed queue length estimation method, and also reveal the existence of QMFD.

关键词： Macroscopic fundamental diagrams(MFD) Floating car data(FCD) queue length VISSIM

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Acta Mathematica Scientia 2000年第3期20卷 397-408页

作者：唐应辉唐小我 Department of Applied Mathematics Management College Univerisity of Electronic Science & Technology of China Chengdu 610054 China

This paper studies the bulk-arrival M-x/G/1 queue with single server vacation. By introducing the server busy period and using the Laplace transform, the recursion expression of the Laplace transform of the transient queue-length distribution is derived. Furthermore, the distribution and stochastic decomposition result of the queue length at a random point in equilibrium are obtained. Especially some results for the single-arrival M/G/1 queue with single server vacation and bulk-arrival M-x/G/1 queue but with no server vacation can be derived directly by the results obtained in this paper.

关键词： server vacation queue length transient distribution equilibrium distribution stochastic decomposition

ANALYSIS OF A CONTINUOUS TIME SM[K]/PH[K]/1/FCFS queue:AGE PROCESS,SOJOURN TIMES,AND queue lengthS

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Journal of Systems Science & Complexity 2012年第1期25卷 133-155页

作者： Qiming HE Department of Management Sciences University of WaterlooWaterlooOntarioN2L 3G1Canada

This paper studies a continuous time queueing system with multiple types of customers and a first-come-first-served service discipline. Customers arrive according to a semi-Markov arrival process and the service times of individual types of customers have PH-distributios. A GI/M/1 type Markov process for a generalized age process of batches of customers is constructed. The stationary distribution of the GI/M/1 type Markov process is found explicitly and, consequently, the distributions of the age of the batch in service, the total workload in the system, waiting times, and sojourn times of different batches and different types of customers are obtained. The paper gives the matrix representations of the PH-distributions of waiting times and sojourn times. Some results are obtained for the distributions of queue lengths at departure epochs and at an arbitrary time. These results can be used to analyze not only the queue length, but also the composition of the queue. Computational methods are developed for calculating steady state distributions related to the queue lengths, sojourn times, and waiting times.

关键词： GI/M/1 type Markov process matrix analytic methods queueing systems queue length semi-Markov chain waiting times.

Methods for determining unimpeded aircraft taxiing time and evaluating airport taxiing performance

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Chinese Journal of Aeronautics 2017年第2期30卷 523-537页

作者： Yu Zhang Qing Wang Civil and Environmental Engineering University of South Florida College of Air Traffic Management Civil Aviation University of China College of Transportation Engineer Tongji University

The objective of this study is to improve the methods of determining unimpeded（nominal） taxiing time,which is the reference time used for estimating taxiing delay,a widely accepted performance indicator of airport surface *** reviewing existing methods used widely by different air navigation service providers（ANSP）,new methods relying on computer software and statistical tools,and econometrics regression models are *** models are highly recommended because they require less detailed data and can serve the needs of general performance analysis of airport surface *** proposed econometrics model outperforms existing ones by introducing more explanatory variables,especially taking aircraft passing and over-passing into the considering of queue length calculation and including runway configuration,ground delay program,and weather *** length of the aircraft queue in the taxiway system and the interaction between queues are major contributors to long taxi-out *** proposed method provides a consistent and more accurate method of calculating taxiing delay and it can be used for ATM-related performance analysis and international comparison.

关键词： Aircraft taxiing Airport performance Econometric regression modeling queue length Simulation analysis Taxiway system

THE TRANSIENT SOLUTION FOR M/G/1 queueWITH SERVER VACATIONS

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Acta Mathematica Scientia 1997年第3期17卷 276-282页

作者：唐应辉 Department of Applied Mathematics University of Electronic Science and Technology of China Chengdu 610054 China

In this paper, the transient solutions for M/G/1 queues with single server vacation and multiple server vacations are firstly studied, and the recursion expressions of their Laplace transform are given. Further the distribution and stochastic decomposition result of the queue length at a random point in equilibrium are directly obtained from the transient solution. As will be seen this paper provides a intuitive and elegant method for studying transient solutions for M/G/1 queues with single server.

关键词： server-vacation queue length transient solution stochastic decomposition

Distributed Packet-Aware Routing Scheme Based on Dynamic Network Coding

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China Communications 2016年第10期13卷 20-28页

作者： Yao Yu Yuhuai Peng Xiaoling Li Jinfeng Gao Xiaozhu Cong School of Computer Science and Engineering Northeastern University

In this paper, we study transmission of packets with time constraints in cooperative 5G wireless networks. As we know, the packets which are transmitted with large delay become useless and have to be dropped. In order to minimize packet dropping probability, we consider multiple transmission methods and integrate packet scheduling with adaptive network coding method selection. Firstly we introduce queue length to obtain the gain of network. Based on this, we present the dynamic coding-aware routing metric, which can increase potential coding opportunities. Moreover, we propose a distributed packet-aware transmission routing scheme based on the above routing metric, which can discover the available paths timely and efficiently. Simulation results show that the proposed method can reduce average packet dropping probability with lower computational complexity.

关键词： 5G network coding-aware routing queue length

Method of spillover identification in urban street networks using loop detector outputs

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Journal of Central South University 2013年第2期20卷 572-578页

作者：马东方王殿海孙锋别一鸣金盛 College of Civil Engineering and Architecture Zhejiang University College of Traffic and Transportation Jilin University

Quick and reliable identification of the traffic state is of critical importance to traffic control systems, especially when spillovers appear. Firstly, a calculation method for the occupancy per cycle under different traffic conditions were presented, based on the relationship between the three basic traffic flow parameters, speed, traffic flow and density. Secondly, the times at which the stopping and starting waves approach a loop detector were confirmed using the traffic wave models modified by a kinematic equation. Then, the threshold of occupancy, which characterizes the appearance of spillovers, was determined by the premise that the stopping and starting waves had the same speed. At last, the accuracy and usability of the new method were verified by VISSIM simulation, using the ratio of misjudgment as the evaluation index. The results show that the ratio of misjudgment of the new method is about 11.36% compared to 17.65% of the previous method.

关键词： occupancy spillover shock wave queue length simulation

Secure and Optimal LOADng Routing for IoT with Composite RoutingMetric

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Computers, Materials & Continua 2023年第1期74卷 655-669页

作者： Divya Sharma Sanjay Jain Vivek Maik Department of Electronics and Communication New Horizon College of EngineeringBengaluru560103India CMR Institute of Technology Bengaluru560037India Department of Electronics and Communication SRM Institute of Science and TechnologyKattankulathurChennai603203India

Security is the one of the major challenges for routing the data between the source and destination in an Internet of Things(IoT)*** overcome this challenge,a secure Lightweight On-demand Ad hoc Distancevector—Next Generation(LOADng)Routing Protocol is proposed in this *** the LOADng protocol is the second version of Ad Hoc On-Demand Distance Vector(AODV)protocol,it retains most of the basic functionality and characteristics of *** the route discovery process,the cyclic shift transposition algorithm(CSTA)is used to encrypt the control packets of the LOADng protocol to improve its *** approach only derives transposition and substitution without product cipher with respect to input *** this,for choosing the best probable path between the source and destination,routing metrics such as link quality Indicator(LQI),hop count(HC)and queue length(QL)are included in the control *** data is then securely sent using CSTA using the optimal secure path *** Results depict that the proposed secure and optimal LOADng(SO-LOADng)using CSTA encryption obtains better throughput,delivery ratio encryption time and decryption time than the existing state-ofart approaches.

关键词： IoT LOADng CSTA link quality indicator queue length

Estimation of Incident-Induced Congestion on Signalized Arteries Using Traffic Sensor Data

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Tsinghua Science and Technology 2012年第3期17卷 296-303页

作者： Lin Hou Zuo Zhang Binghao Lu Runmin Xu Yi Zhang Tsinghua National Laboratory for Information Science and Technology Department of AutomationTsinghua UniversityBeijing 100084China

This paper describes how to derive quantitative information about the effect of traffic incidents on urban traffic flow from the raw measurements detected by sectional loop sensors. 3-he two critical parame- ters of the travel delay and queue length, which reflect the temporal and spatial properties of inci- dent-induced congestion, cannot be directly determined from commonly used loop sensors. The modified queuing diagram is used here to quantify incident-induced queues and travel delays on signalized arteries using sensor data from the targeted and upstream links. The method is tested using data generated by the VISSIM simulation model, with results indicating its efficiency and accuracy with an average relative travel delay error of 18.67% for all samples which falls to 8.07% for high volume and very high volume conditions.

关键词： traffic incident signalized intersections travel delay queue length