scholarly journals Capacity Gains of Splitting Cross-Traffic into Multiple Sub-Streams

2021 ◽  
pp. 036119812110366
Author(s):  
Victor L. Knoop ◽  
Maria Jettina Wierbos ◽  
Otto van Boggelen
Keyword(s):  
Traffic Flow ◽  
Main Stream ◽  
Traffic Splitting ◽  
Car Traffic ◽  
Cross Traffic ◽  
The Cross ◽  
Intersection Design

Traffic flow might be limited by cross-traffic which has priority. A typical example of such a situation is a location where cyclists or pedestrians cross a stream of car traffic. Splitting the cross-traffic into two separate sub-streams (for instance left–right and right–left) can increase the capacity of the main stream. This is because it is no longer necessary to have a sufficiently large gap in both sub-streams simultaneously. This paper introduces a method to compute the resulting capacity of roads with cross-traffic. Without loss of generality, we introduce three transformations to simplify computations. These transformations are an important contribution of the paper, allowing us to create scalable graphs for capacity. Overall, the research shows that splitting a crossing stream into two equally large sub-streams increases the capacity of the main stream. If there is place for one vehicle in between two sub-streams, the capacity can increase up to threefold. Even larger gains are possible with more vehicles in between. This paper presents graphs which can be used to find the capacity for generic situations, and can be used for developing guidelines on intersection design.

Design Gap Acceptance for Right-Turning Vehicles Based on Vehicle Acceleration Capabilities

2015 ◽  
Vol 2521 (1) ◽  
pp. 12-21 ◽  
Author(s):  
Essam Dabbour
Keyword(s):  
Regression Models ◽  
Field Measurements ◽  
Data Logger ◽  
Sight Distance ◽  
Design Guide ◽  
Traffic Stream ◽  
Cross Traffic ◽  
Vehicle Acceleration ◽  
The Cross ◽  
The Right

The current geometric design guide provides a methodology to analyze intersection sight distance for right-turning vehicles at signalized and two-way stop-controlled intersections based on the gaps accepted by the majority of drivers as measured from the field. That methodology is based mainly on driver behavior without considering the actual capabilities of the turning vehicle when accelerating from rest to the speed of the cross-traffic stream. This paper introduced the new design gap concept, which was based on the actual distance and time needed for the turning vehicle to accelerate to the same speed of the cross-traffic stream to avoid a collision. The acceleration capabilities of the turning vehicle were based on field measurements collected by GPS data logger devices that recorded the positions and instantaneous speeds of different turning vehicles at 1-s intervals; based on that, regression models were developed to establish an acceleration profile for a typical vehicle turning to the right from rest. Design tables were provided to help road designers select appropriate design gaps needed for different design speeds and grades of the crossing roadways. In comparison to the new design gaps, the measured gaps used in design were found to be generally inadequate. After implementation of the newly developed design gaps, turning drivers will potentially be able to accelerate comfortably without forcing other drivers in the cross-traffic stream to reduce their speeds or to change lanes to avoid colliding with turning vehicles.

Using AIS Data for Navigational Risk Assessment in Restricted Waters

2013 ◽  
pp. 245-254
Author(s):  
Adi Maimun ◽  
Istaz F. Nursyirman ◽  
Ang Yit Sian ◽  
Rahimuddin Samad ◽  
Sulaiman Oladokun
Keyword(s):  
Risk Assessment ◽  
Traffic Flow ◽  
Assessment Method ◽  
Collision Probability ◽  
Traffic Density ◽  
Automatic Identification ◽  
High Concentration ◽  
Marine Traffic ◽  
Cross Traffic ◽  
Strait Of Malacca

The Strait of Malacca is one of the most important shipping lanes in the world. It averages 150 ship passes a day and more than 50,000 ships annually. With a high concentration of vessels in a narrow path, multiple risk situations arise. Analyzing traffic density is made harder by cross traffic and an unknown traffic density at the Strait. In 2009, Universiti Teknologi Malaysia (UTM), through a collaboration with Kobe University, successfully installed an Automatic Identification System (AIS) receiver. Through the AIS receiver, data of ship movements in the Strait of Malacca and Singapore could be recorded. A program was established by UTM to retrieve the data for the purpose of marine traffic collision risk analysis. In this research, a risk assessment method using AIS data is proposed for restricted waters such as for the Strait of Malacca and Singapore. The Risk Assessment Methodology requires the estimation of collision probabilities. The collision probability of the proposed method considers the Traffic Density, directions of traffic flow (with respect to a subject vessel), and probability of navigational failure. An area in the Strait of Singapore between the latitudes of 1°13’N and 1°07’N and Longitudes of 103°4’E and 103°56’E was selected to illustrate the method. By analysing the AIS data of traffic flow, the probabilities of collision for the area were determined. The effect of vessel parameters of length and speed on the risks of collision are also shown.

Public Transport Preference as the Tool to Manage Traffic Flow and to Increase Service Quality from a Customer Point of View

2015 ◽  
Vol 803 ◽  
pp. 17-23 ◽  
Author(s):  
Maria Kostolna ◽  
Simona Kubikova ◽  
Vladimir Konecny
Keyword(s):  
Traffic Flow ◽  
Quality Evaluation ◽  
Road Traffic ◽  
Point Of View ◽  
Urban Transport ◽  
Transport Networks ◽  
Car Traffic ◽  
High Investment ◽  
Further Development ◽  
Satisfaction With Services

The increase of individual car traffic causes that existing transport networks fail to meet the needs of road traffic in the means of capacity. One of the possible options for solving this problem is the construction of new communications. This solution is difficult to implement due to the high investment costs and possibility for further development. Therefore, one of the options for avoiding this problem is to make public urban transport more attractive, for example, through its support and preference. One of the main criteria in the quality evaluation of public urban transport is the transfer speed from origin to destination. This speed can be most noticeably affected by the use of public urban transport preference.This paper will discuss the analysis of passengers’ satisfaction with services provided by carriers of urban transport and the possibilities of public urban transport preference through the preference of public urban transport vehicles in reserved traffic lanes and on signal controlled intersections.

scholarly journals General Identifiability Condition for Network Topology Monitoring with Network Tomography

Sensors ◽  
2019 ◽  
Vol 19 (19) ◽  
pp. 4125 ◽  
Author(s):  
Shengli Pan ◽  
Zongwang Zhang ◽  
Zhiyong Zhang ◽  
Deze Zeng ◽  
Rui Xu ◽  
...  
Keyword(s):  
Network Topology ◽  
Network Monitoring ◽  
Time Varying ◽  
Network Tomography ◽  
Accurate Knowledge ◽  
Cross Traffic ◽  
End To End ◽  
The Cross

Accurate knowledge of network topology is vital for network monitoring and management. Network tomography can probe the underlying topologies of the intervening networks solely by sending and receiving packets between end hosts: the performance correlations of the end-to-end paths between each pair of end hosts can be mapped to the lengths of their shared paths, which could be further used to identify the interior nodes and links. However, such performance correlations are usually heavily affected by the time-varying cross-traffic, making it hard to keep the estimated lengths consistent during different measurement periods, i.e., once inconsistent measurements are collected, a biased inference of the network topology then will be yielded. In this paper, we prove conditions under which it is sufficient to identify the network topology accurately against the time-varying cross-traffic. Our insight is that even though the estimated length of the shared path between two paths might be “zoomed in or out” by the cross-traffic, the network topology can still be recovered faithfully as long as we obtain the relative lengths of the shared paths between any three paths accurately.

Double Wall Cooling of an Effusion Plate With Simultaneous Cross Flow and Impingement Jet Array Internal Cooling

2019 ◽  
Vol 141 (9) ◽  
Author(s):  
David Ritchie ◽  
Austin Click ◽  
Phillip M. Ligrani ◽  
Federico Liberatore ◽  
Rajeshriben Patel ◽  
...  
Keyword(s):  
Heat Flux ◽  
Reynolds Number ◽  
Stream Flow ◽  
Cross Flow ◽  
Main Stream ◽  
Streamwise Location ◽  
Net Heat Flux ◽  
Contraction Ratio ◽  
The Cross ◽  
Double Wall

Considered is double wall cooling, with full-coverage effusion-cooling on the hot side of the effusion plate, and a combination of impingement cooling and cross flow cooling, employed together on the cold side of the effusion plate. Data are given for a main stream flow passage with a contraction ratio (CR) of 4 for main stream Reynolds numbers Rems and Rems,avg of 157,000–161,000 and 233,000–244,000, respectively. Hot-side measurements (on the main stream flow or hot side of the effusion plate) are presented, which are measured using infrared thermography. Using a transient thermal measurement approach, measured are spatially resolved distributions of surface adiabatic film cooling effectiveness, and surface heat transfer coefficient. For the same Reynolds number, initial blowing ratio (BR), and streamwise location, increased thermal protection is often provided when the effusion coolant is provided by the cross flow/impingement combination configuration, compared to the cross flow only supply arrangement. In general, higher adiabatic effectiveness values are provided by the impingement only arrangement, relative to the impingement/cross flow combination configuration, when compared at the same Reynolds number, initial BR, and x/de location. Data for one streamwise location of x/de = 60 show that the highest net heat flux reduction line-averaged net heat flux reduction (NHFR) values are produced either by the impingement/cross flow combination configuration or by the impingement only arrangement, depending upon the particular magnitude of BR, which is considered.

Crossing Traffic Separation Schemes

1979 ◽  
Vol 32 (3) ◽  
pp. 429-429
Author(s):  
R. S. Richardson
Keyword(s):  
Traffic Flow ◽  
Traffic Density ◽  
Apparent Lack ◽  
General Direction ◽  
Right Of Way ◽  
Cross Traffic ◽  
The Right ◽  
High Traffic Density ◽  
Crossing Vessels ◽  
Do So

The provision of Rule 10 of the 1972 Collision Regulations, that if vessels are obliged to cross traffic lanes they shall do so as nearly as practicable at right angles to the general direction of traffic flow, would appear to be simple enough. Could it be however that in areas of high traffic density, such as the Dover Strait, the theoretical simplicity of the right-angle crossing introduces problems of its own?Crossing the Dover Strait several times a week, I am constantly alarmed by the apparent lack of regard for Rules 15 and 16 by vessels using the traffic scheme (The rules governing crossing situations and action required by the give-way vessel). I accept that some vessels using the lane believe, albeit incorrectly, that they have the right of way, but feel that a large proportion of these ‘port-side charlies’ are the result of the right-angle crossing.Because of the pattern of traffic the speed of crossing vessels in the Strait is generally considerably greater than that of vessels using the lanes. Under the present Regulations a situation frequently arises in which a vessel using the lane finds herself as the give-way vessel to another six points or more on her bow. An initial reluctance to alter course by this amount is followed by the thought that there is not sufficient sea-room in which to alter, and the give-way vessel stands on.

MODELING THE INTERACTION BETWEEN MOTORIZED VEHICLE AND BICYCLE BY USING CELLULAR AUTOMATA MODEL

2009 ◽  
Vol 20 (02) ◽  
pp. 209-222 ◽  
Author(s):  
XIN-GANG LI ◽  
ZI-YOU GAO ◽  
BIN JIA ◽  
XIAO-MEI ZHAO
Keyword(s):  
Cellular Automata ◽  
Traffic Flow ◽  
Future Research ◽  
Mixed Traffic ◽  
Cross Point ◽  
Cellular Automata Model ◽  
Mixed Traffic Flow ◽  
Simulation Results ◽  
The Cross ◽  
The Right

In this paper, the cellular automata models for motorized vehicle flow and that for bicycle flow are combined to modeling the interactions between the right-turning motorized vehicle and the driving ahead bicycle at intersection. We introduce the probability that the cross point is taken up by the same kind of vehicle during two successive time steps to describe the complex behaviors when conflict happens. The flux of both motorized vehicle and bicycle depending on the inflow rates are investigated and the spatiotemporal diagrams are also presented to show different traffic states as the inflow rates change. The simulation results show that the model can describe the interactions between motorized vehicle and bicycle. It makes foundations for future research on mixed traffic flow.

Land Use-Slow Traffic and Demand Forecasting

2017 ◽  
Vol 42 (3) ◽  
pp. 130-134
Author(s):  
Ren Hong ◽  
Zhang Zhengtong ◽  
Ma Xianrui ◽  
Tang Xilai
Keyword(s):  
Land Use ◽  
Traffic Flow ◽  
Traffic Congestion ◽  
Population Distribution ◽  
Demand Forecasting ◽  
Urban Traffic ◽  
High Tech ◽  
Traffic Demand ◽  
The Cross ◽  
Traffic Systems

In the face of solving the urban traffic congestion problem radically, emphasis has been laid on the research on slow traffic planning of urban built environment. Hence, research on slow traffic demand forecasting can provide a basis for the planning of urban slow traffic systems. Based on land use, the overall planning of the new Guangming (GM) district, and the population prediction results, the slow traffic demand within the scope of the new district was forecasted by combining the per capita trip frequency, and the spatial distribution of the slow traffic flow of the new GM district was forecasted per the forecasted demand quantity for slow traffic. The following research conclusions were obtained. Within the new GM district, the correlation of the total demand for slow traffic with the land use functions and population distribution was high, and the cross-zone traffic was mainly decided by the land usage of this district. The cross-unit slow traffic flow was concentrated in the Gongming central, Guangming central, high-tech zone, and Yutian zones. This research provides a guideline for the layout of slow traffic facilities in the future.

CROSS-CORRELATION ANALYSIS IN MIXED TRAFFIC FLOW TIME SERIES

2011 ◽  
Vol 25 (13) ◽  
pp. 1823-1832 ◽  
Author(s):  
S. Y. XU ◽  
H. J. SUN ◽  
J. J. WU
Keyword(s):  
Time Series ◽  
Traffic Flow ◽  
Correlation Coefficient ◽  
Linear Correlation ◽  
Cross Correlation ◽  
Flow Time ◽  
Mixed Traffic ◽  
Mixed Traffic Flow ◽  
Vehicle Density ◽  
The Cross

In this paper, we investigate the complexity behind the mixed traffic flow time series generated by multi-lane cellular automaton model. Throughout the paper, the cross-correlation coefficient is introduced to characterize the time series. It is found that there exists a critical vehicle density S, when S < S1 and the ratio of slow vehicle R > 0.01, the cross-correlation coefficient r is larger than 0.5, which indicates a significant linear correlation. Otherwise, the cross-correlation coefficient r < 0.5 which corresponds to a weak linear correlation. That is to say, the vehicle density plays an important role in the cross-correlation coefficient. Additionally, we also found that the asymmetric lane-change probability has no great influence on the cross-correlation coefficient.

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