Optimal detector location for estimating link travel speed in urban arterial roads

2004 ◽  
Vol 8 (3) ◽  
pp. 327-333 ◽  
Author(s):  
Sungho Oh ◽  
Keechoo Choi
2004 ◽  
Vol 1867 (1) ◽  
pp. 144-150 ◽  
Author(s):  
Hongchao Liu ◽  
Alexander Skabardonis ◽  
Wei-bin Zhang ◽  
Meng Li

Author(s):  
Guangwei Zhou ◽  
Albert Gan

Queue jumper lanes are a special type of bus preferential treatment that allows buses to bypass a waiting queue through a right-turn bay and then cut out in front of the queue by getting an early green signal. The performance of queue jumper lanes is evaluated under different transit signal priority (TSP) strategies, traffic volumes, bus volumes, dwell times, and bus stop and detector locations. Four TSP strategies are considered: green extension, red truncation, phase skip, and phase insertion. It was found that queue jumper lanes without TSP were ineffective in reducing bus delay. Queue jumper lanes with TSP strategies that include a phase insertion were found to be more effective in reducing bus delay while also improving general vehicle operations than those strategies that do not include this treatment. Nearside bus stops upstream of check-in detectors were preferred for jumper TSP over farside bus stops and nearside bus stops downstream of check-in detectors. Through vehicles on the bus approach were found to have only a slight impact on bus delay when the volume-to-capacity (v/c) ratio was below 0.9. However, when v/c exceeded 0.9, bus delay increased quickly. Right-turn volumes were found to have an insignificant impact on average bus delay, and an optimal detector location that minimizes bus delay under local conditions was shown to exist.


Author(s):  
Sugiarto Sugiarto ◽  
. Lulusi ◽  
Sofyan M. Saleh

<span lang="EN-US">The term of capacity is very useful to quantify the ability of transport facilities in terms of carrying traffic. The capacity of the road is an essential ingredient in the planning, design, and operation of roadways. It is desirable for traffic analyst to be able to predict the time and places where congestion will occur and the volumes to be expected. Most of urbanized areas have been experiencing of traffic congestion problems particularly at urban arterial systems. High traffic demand and limited supply of roadways are always the main factors produced traffic congestion. However, there are other sources of local and temporal congestion, such as uncontrolled access point, median opening and on-street parking activities, which are caused a reduction of roadway capacity during peak operations. </span><span lang="EN-US">Those locations could result in reduction of travel speed and road, as known as hidden bottlenecks. This is bottleneck which is without any changes in geometric of the segments. The Indonesian Highway Capacity Manual (IHCM, 1997) is used to assess urban arterial systems till current days. IHCM provides a static method for examining the capacity</span><span lang="EN-US">and does not systematically take into account of bottleneck activities. However, bottleneck activities create interruption smooth traffic flow along arterial streets, which in turns stimulate related problems, such as, excessive air pollution, additional energy consumption and driver’s frustration due to traffic jammed. This condition could happen simultaneously; mostly repetitive and predictable in same peak hour demands. Therefore, this paper carefully summarize on the existing methodologies considering required data, handled data processing and expected output of each proposed of analysis. We further notice that dynamic approach could be more appropriated for analyzing temporal congestion segments (median opening, on street parking, etc.). Method of oblique cumulative plot seems to be more applicable in terms of convenient, surveying tool and the accuracy of analysis. This method is easy to handle and powerful in identifying flow and speed fluctuations during breakdown occurs</span>


2000 ◽  
Vol 1710 (1) ◽  
pp. 231-238
Author(s):  
Andrzej P. Tarko

Filtering and metering of traffic at highway bottlenecks influence delay and travel speeds along congested arterial streets. The current Highway Capacity Manual (HCM) method of analyzing urban arterial streets uses the filtering and metering adjustment factor I but does not give recommendations on how to adjust traffic volumes. An improved method of analyzing signalized arterial streets affected by bottlenecks is proposed. A set of equations has been derived to calculate the coefficient I and to adjust the traffic volumes. Conditions in which measured or predicted volumes should be adjusted and conditions in which they do not have to be adjusted are specified. The proposed method incorporates the effect of turning volumes, a feature not present in the current HCM method. A sensitivity analysis of travel speeds along an example signalized arterial street illustrates the filtering and metering effects and compares the results produced by the existing and proposed methods. The differences in the results are considerable. In addition, the significant effect of turning volumes has been confirmed. The proposed method tends to produce travel speeds higher than the values obtained with the current method, which concurs with comments from the users of the HCM that the current method underestimates travel speeds. The filtering equation has been derived with the assumptions of fixed capacity and no vehicle dispersion. Under the conditions violating these assumptions, the filtering equation may underestimate I. Further, the proposed method does not incorporate the effect of long queues blocking upstream lane groups. The negative effect on travel speed estimates along the entire arterial should be limited or negligible.


Author(s):  
Andrew P. Tarko ◽  
Kasem Choocharukul ◽  
Abhishek Bhargava ◽  
Kumares C. Sinha

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