scholarly journals DELAYS AT SIGNALIZED INTERSECTIONS WITH EXHAUSTIVE TRAFFIC CONTROL

2012 ◽  
Vol 26 (3) ◽  
pp. 337-373 ◽  
Author(s):  
M.A.A. Boon ◽  
I.J.B.F. Adan ◽  
E.M.M. Winands ◽  
D.G. Down
Keyword(s):  
Closed Form ◽  
Traffic Control ◽  
Heavy Traffic ◽  
Interarrival Time ◽  
Traffic Signal Control ◽  
Stay Green ◽  
Traffic Lights ◽  
Traffic Intersection ◽  
Poisson Arrivals ◽  
The Mean

In this paper, we study a traffic intersection with vehicle-actuated traffic signal control. Traffic lights stay green until all lanes within a group are emptied. Assuming general renewal arrival processes, we derive exact limiting distributions of the delays under heavy traffic (HT) conditions. Furthermore, we derive the light traffic (LT) limit of the mean delays for intersections with Poisson arrivals, and develop a heuristic adaptation of this limit to capture the LT behavior for other interarrival-time distributions. We combine the LT and HT results to develop closed-form approximations for the mean delays of vehicles in each lane. These closed-form approximations are quite accurate, very insightful, and simple to implement.

Multiple channel queues in heavy traffic. I

1970 ◽  
Vol 2 (01) ◽  
pp. 150-177 ◽  
Author(s):  
Donald L. Iglehart ◽  
Ward Whitt
Keyword(s):  
Heavy Traffic ◽  
Arrival Rate ◽  
Standard System ◽  
Interarrival Time ◽  
Service Rate ◽  
Service Channel ◽  
Multiple Channel ◽  
System A ◽  
The Mean ◽  
Service Channels

The queueing systems considered in this paper consist of r independent arrival channels and s independent service channels, where as usual the arrival and service channels are independent. Arriving customers form a single queue and are served in the order of their arrival without defections. We shall treat two distinct modes of operation for the service channels. In the standard system a waiting customer is assigned to the first available service channel and the servers (servers ≡ service channels) are shut off when they are idle. Thus the classical GI/G/s system is a special case of our standard system. In the modified system a waiting customer is assigned to the service channel that can complete his service first and the servers are not shut off when they are idle. While the modified system is of some interest in its own right, we introduce it primarily as an analytical tool. Let λ i denote the arrival rate (reciprocal of the mean interarrival time) in the ith arrival channel and μ j the service rate (reciprocal of the mean service time) in the jth service channel. Then is the total arrival rate to the system and is the maximum service rate of the system. As a measure of congestion we define the traffic intensity ρ = λ/μ.

Multiple channel queues in heavy traffic. I

1970 ◽  
Vol 2 (1) ◽  
pp. 150-177 ◽  
Author(s):  
Donald L. Iglehart ◽  
Ward Whitt
Keyword(s):  
Heavy Traffic ◽  
Arrival Rate ◽  
Standard System ◽  
Interarrival Time ◽  
Service Rate ◽  
Service Channel ◽  
Multiple Channel ◽  
System A ◽  
The Mean ◽  
Service Channels

The queueing systems considered in this paper consist of r independent arrival channels and s independent service channels, where as usual the arrival and service channels are independent. Arriving customers form a single queue and are served in the order of their arrival without defections. We shall treat two distinct modes of operation for the service channels. In the standard system a waiting customer is assigned to the first available service channel and the servers (servers ≡ service channels) are shut off when they are idle. Thus the classical GI/G/s system is a special case of our standard system. In the modified system a waiting customer is assigned to the service channel that can complete his service first and the servers are not shut off when they are idle. While the modified system is of some interest in its own right, we introduce it primarily as an analytical tool. Let λi denote the arrival rate (reciprocal of the mean interarrival time) in the ith arrival channel and μj the service rate (reciprocal of the mean service time) in the jth service channel. Then is the total arrival rate to the system and is the maximum service rate of the system. As a measure of congestion we define the traffic intensity ρ = λ/μ.

Traffic Signal Control and Simulation of Single Intersection Based on Fuzzy Control

2013 ◽  
Vol 756-759 ◽  
pp. 458-462
Author(s):  
Hong Xiang Xiao ◽  
Ye Fu Zhu
Keyword(s):  
Fuzzy Control ◽  
Traffic Control ◽  
Control Unit ◽  
Basic Structure ◽  
Transportation System ◽  
Traffic Signal Control ◽  
Control Technology ◽  
Agent Based ◽  
Traffic Lights ◽  
Intersection Control

In this paper, they are proposed that the Agent-based single intersection traffic control and analysis of the basic structure of a single intersection based on Agent, modeling them. Single intersection is the basic control unit of the entire transportation system. The superior single intersection control is protecting transport network uptime. Agent-based traffic control combines the advantage of fuzzy control in complex transportation system; the fuzzy control technology used in traffic lights control decisions

scholarly journals Incorporating Queueing Dynamics into Schedule-Driven Traffic Control

2021 ◽  
Author(s):  
Hsu-Chieh Hu ◽  
Allen M. Hawkes ◽  
Stephen F. Smith
Keyword(s):  
Traffic Control ◽  
Planning Process ◽  
Heavy Traffic ◽  
Traffic Signal Control ◽  
Signal Timing ◽  
Time Model ◽  
Real Time Traffic ◽  
Online Planning ◽  
Queueing Delay ◽  
Pass Through

Key to the effectiveness of schedule-driven approaches to real-time traffic control is an ability to accurately predict when sensed vehicles will arrive at and pass through the intersection. Prior work in schedule-driven traffic control has assumed a static vehicle arrival model. However, this static predictive model ignores the fact that the queue count and the incurred delay should vary as different partial signal timing schedules (i.e., different possible futures) are explored during the online planning process. In this paper, we propose an alternative arrival time model that incorporates queueing dynamics into this forward search process for a signal timing schedule, to more accurately capture how the intersection’s queues vary over time. As each search state is generated, an incremental queueing delay is dynamically projected for each vehicle. The resulting total queueing delay is then considered in addition to the cumulative delay caused by signal operations. We demonstrate the potential of this approach through microscopic traffic simulation of a real-world road network, showing a 10-15% reduction in average wait times over the schedule-driven traffic signal control system in heavy traffic scenarios.

Complex Solution of Ecological and Economic Problems of Traffic Jams

2019 ◽  
pp. 6-15
Author(s):  
Oleksandr M. Matsenko ◽  
Yaroslav S. Kovalev ◽  
Olena M. Tkachenko ◽  
Yaroslava V. Chorna
Keyword(s):  
Traffic Control ◽  
Motor Vehicle ◽  
Motor Vehicles ◽  
Water Runoff ◽  
Negative Consequences ◽  
Traffic Lights ◽  
Economic Problems ◽  
Traffic Jams ◽  
Economic Sphere ◽  
Flows Over Time

The article explores the congestion level in traffic of motor vehicles and its negative environmental and economic consequences in case of Kiev. The amount of pollution from traffic jams in Kiev and the number of vehicles which got into them in 2009-2018 is analyzed. The loss of earnings on the side of automobile owners from their standby are calculated with corresponding quantitative expressions found and described. For the course of the research, the methods of system-structural and comparative analysis were used for analyzing the environmental and economic problems of modern automobile systems; methods of formal logical analysis were used for substantiating the innovative infrastructure of transport routes. Separately economic and statistical methods were used in the study for trends development, structure analysis, and estimation of the influence of road congestion on the environmental and economic sphere. Pearson test has indicated a close relationship between the number of cars in Kiev and the number of values from traffic jams in environmental and economic sphere. Solutions to this problem are offered in forms of automated traffic control systems, improvisation of organizational and technical methods for the distribution of traffic flows over time, namely reverse traffic, road junctions, smart traffic lights, road extension, and the transition to alternative modes of transport. In all countries of the world there are new research methods that affect pollutants from motor vehicles. It is proved that they are forced by the recipients. In addition, landscaping can improve landscape design, reduce greenhouse gas emissions, surface water runoff and noise pollution. In this regard the policy implication of the research are aimed to eliminate the negative consequences from the use of vehicles during traffic jams, and the necessary number of trees for planting in Kiev is calculated. Key words: motor transport, congestion, traffic jam, motor vehicle, greening, compensation effect, lost profits, losses.

SET-VALUED PERFORMANCE APPROXIMATIONS FOR THE QUEUE GIVEN PARTIAL INFORMATION

2020 ◽  
pp. 1-23
Author(s):  
Yan Chen ◽  
Ward Whitt
Keyword(s):  
Steady State ◽  
Decay Rate ◽  
Waiting Time ◽  
Partial Information ◽  
Upper And Lower Bounds ◽  
Interarrival Time ◽  
Limited Information ◽  
Wide Range ◽  
The Mean ◽  
Third Moment

In order to understand queueing performance given only partial information about the model, we propose determining intervals of likely values of performance measures given that limited information. We illustrate this approach for the mean steady-state waiting time in the $GI/GI/K$ queue. We start by specifying the first two moments of the interarrival-time and service-time distributions, and then consider additional information about these underlying distributions, in particular, a third moment and a Laplace transform value. As a theoretical basis, we apply extremal models yielding tight upper and lower bounds on the asymptotic decay rate of the steady-state waiting-time tail probability. We illustrate by constructing the theoretically justified intervals of values for the decay rate and the associated heuristically determined interval of values for the mean waiting times. Without extra information, the extremal models involve two-point distributions, which yield a wide range for the mean. Adding constraints on the third moment and a transform value produces three-point extremal distributions, which significantly reduce the range, producing practical levels of accuracy.

scholarly journals End-to-End Data Rate Performance of Decode-and-Forward Relaying with Different Resource Allocation Schemes

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Inam Ullah ◽  
Alexis Dowhuszko ◽  
Zhong Zheng ◽  
David González González ◽  
Jyri Hämäläinen
Keyword(s):  
Resource Allocation ◽  
Closed Form ◽  
Data Rate ◽  
Allocation Scheme ◽  
Optimal Resource Allocation ◽  
Decode And Forward ◽  
Optimal Resource ◽  
The Mean ◽  
Resource Allocation Scheme ◽  
Resource Allocation Schemes

This paper studies the end-to-end (e2e) data rate of dual-hop Decode-and-Forward (DF) infrastructure relaying under different resource allocation schemes. In this context, we first provide a comparative analysis of the optimal resource allocation scheme with respect to several other approaches in order to provide insights into the system behavior and show the benefits of each alternative. Then, assuming the optimal resource allocation, a closed form expression for the distribution of the mean and outage data rates is derived. It turns out that the corresponding mean e2e data rate formula attains an expression in terms of an integral that does not admit a closed form solution. Therefore, a tight lower bound formula for the mean e2e data rate is presented. Results can be used to select the most convenient resource allocation scheme and perform link dimensioning in the network planning phase, showing the explicit relationships that exist between component link bandwidths, SNR values, and mean data rate.

Leakage Prediction in Mechanical Seals Under Hydrostatic Operating Condition

2007 ◽  
Author(s):  
S. Elhanafi ◽  
K. Farhang
Keyword(s):  
Closed Form ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Rough Surfaces ◽  
Mechanical Seals ◽  
Operating Condition ◽  
Form Equation ◽  
Macro Scale ◽  
The Mean

This paper considers leakage in mechanical seals under hydrostatic operating condition. A contact model based on the Greenwood and Williamson contact of rough surfaces is developed for treating problems involving mechanical seals in which both the micron scale roughness of the seal face and its macro scale profile are used to obtain either a closed-form equation or a nonlinear equation relating mean plane separation to the mass flow rate. The equations involve the micron scale geometry of the rough surfaces and physical parameter of the seal and carriage. Under hydrostatic condition, it is shown that there is an approximate closed-form solution in which mass flow rate in terms of the mean plane separation, or alternatively, the mean plane separation in terms of the leakage mass flow rate is found. Equations pertaining to leakage in nominally flat seal macro profile is considered and closed form equation relating to leakage flow rate to pressure difference is obtained that contain macro and micron geometries of the seal.

Application of PLC in the Expressway Intelligent Traffic Control System

2013 ◽  
Vol 361-363 ◽  
pp. 2219-2223
Author(s):  
Xin Hua Wei ◽  
Xian Xing Duan ◽  
Xiao Kan Wang
Keyword(s):  
Control System ◽  
Traffic Control ◽  
Flow Speed ◽  
The Body ◽  
Host Computer ◽  
Scientific Management ◽  
Traffic Lights ◽  
Traffic Control System ◽  
Vehicle Size ◽  
Sense Coil

The expressway intelligent traffic control system based on S7-200 series Programmable Logic Controller (PLC) was introduced in this paper.PLC has strong adaptability in the complex environment and rich internal timer resources, it is easily to realize accuracy controlling the traffic lights, specially for multi-crossroads.PLC analyzed and processed the signals of the body flow, speed, vehicle size and other data by the sense coil, then transmitting the information to the host computer. The host computer might automatically adjust the length of time from the final signal to achieve intelligent scientific management of traffic lights.

Coupled dynamics of populations supported by discrete sites and their continuum limit

2010 ◽  
Vol 466 (2121) ◽  
pp. 2561-2586 ◽  
Author(s):  
Timothy R. Field ◽  
Robert J. A. Tough
Keyword(s):  
Evolution Equation ◽  
Closed Form ◽  
Generating Function ◽  
Rate Equation ◽  
Continuum Limit ◽  
Infinite Chain ◽  
Migration Process ◽  
The Mean ◽  
The Continuum ◽  
Birth Death

The illumination of single population behaviour subject to the processes of birth, death and immigration has provided a basis for the discussion of the non-Gaussian statistical and temporal correlation properties of scattered radiation. As a first step towards the modelling of its spatial correlations, we consider the populations supported by an infinite chain of discrete sites, each subject to birth, death and immigration and coupled by migration between adjacent sites. To provide some motivation, and illustrate the techniques we will use, the migration process for a single particle on an infinite chain of sites is introduced and its diffusion dynamics derived. A certain continuum limit is identified and its properties studied via asymptotic analysis. This forms the basis of the multi-particle model of a coupled population subject to single site birth, death and immigration processes, in addition to inter-site migration. A discrete rate equation is formulated and its generating function dynamics derived. This facilitates derivation of the equations of motion for the first- and second-order cumulants, thus generalizing the earlier results of Bailey through the incorporation of immigration at each site. We present a novel matrix formalism operating in the time domain that enables solution of these equations yielding the mean occupancy and inter-site variances in the closed form. The results for the first two moments at a single time are used to derive expressions for the asymptotic time-delayed correlation functions, which relates to Glauber’s analysis of an Ising model. The paper concludes with an analysis of the continuum limit of the birth–death–immigration–migration process in terms of a path integral formalism. The continuum rate equation and evolution equation for the generating function are developed, from which the evolution equation of the mean occupancy is derived, in this limit. Its solution is provided in closed form.

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