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Unformatted text preview: eveloped using ARENA simulation program. The model developed to provide the delay
estimation when a lane closure occurs and to visually demonstrate the forecasted delay.
Lane changing and car following algorithms were included in the simulation model. The
authors investigated the effects of the slow moving vehicles and late mergers using the
developed simulation model. They compared the results of the developed simulation
model, traffic flow rate, speed, and delay time with the actual data. They found that the
outputs of the model establish a level of confidence that the model is capable of
simulating the conditions of the work zone. The results of their study showed that with
traffic volumes less than 700 vehicles per hour, it is unlikely to observe delay at the lane
closures. At traffic volumes of 950 vehicles per hour, it is more likely to observe delay in 6
the construction work zones. The authors were contacted in order to get more information
about the details of the ARENA simulation model, but no information was obtained about
the architecture of the model.
Al-Kaisy, Stewart and Van Aerde  performed a simulation study to examine
the capacity and the operational performance at freeway diverge a
reas. In order to
understand the traffic behavior at freeway diverge areas, they used microscopic traffic
simulation model INTEGRATION. Car following behavior and lane changing behavior
are the most important features of INTEGRATION for simulating freeway operations.
Using the user specified free flow speed, speed at capacity, capacity and jam density
single regime speed flow density relationship is determined in the model. Another
important feature of the program is that it includes both mandatory and discretionary lane
changing behavior. Mandatory lane changing occurs when a driver must change the lane
because of the ending lane or closed lane, and discretionary lane changing occurs when
the other lane provides better driving conditions. Al-Kaisy et al. developed their model at
an exit ramp. They analyzed different deceleration lane lengths at exit ramps and their
effects on capacity and operational performance at freeway diverge areas. .
Benekohal and Abu-Lebdeh  performed a variability analysis, using the
stochastic traffic simulation model TRAF-NETSIM outputs. In the study the authors used
batch means and replications to assess variability in the measure of effectiveness
calculations of NETSIM. They used average delay, average speed, and vehicle trips as
the measures of effectiveness parameters. The outputs of the simulation model are
analyzed by the statistical methods such as batch means method, replication method, and
correlation among batches method. The batch means method is performed by running the 7
program for one long replication and dividing it into smaller batches. Statistics are
collected and using the variability within the batches, a confidence interval is build for
the model. Another way of building confidence interval is replication method. In this
method multiple independent replications having same roadway and traffic conditions are
run for the model and statistics on the system performance are collected. Statistics for the
batches may be treated as stationary time series data, when a long run is divided into
batches. Plot of the mean value for each batch against time will help to determine
whether the time series is stationary. The authors proposed an interval calculation method
and compared the results of the simulation model with the results they calculated using
the proposed interval calculation method. Their study showed that with the proposed
interval calculation method they could build confidence intervals for the measure of
Bloomberg and Dale  compared microscopic simulation models VISSIM and
CORSIM by using them in a study for designing alternatives in Seattle, Washington.
CORSIM was developed by FHWA to analyze freeways, urban streets, and corridors or
networks. VISSIM was developed at the University of Karlsruhe, Germany to analyze
functionally classified roadways and public transportation operations. In order to
compare these two simulation models, the authors applied the models to analyze the
alternatives for the project performed by Washington State Department of Transportation.
Six different scenarios were analyzed using the models. The authors find differences in
the car following logic, network-coding process, gap acceptance, modeling of signals,
animation features and output data of the models. The network coding process is different
between the two models. CORSIM uses a link- node structure wherein the user defines the 8
attributes such as speed, lane configurations, and traffic control devices to the links and
nodes. In VISSIM use of nodes is eliminated, the model relies on links and connecters
which allow the user to match the network geometry to field conditions. The car
following model in CORSIM sets a desired amount of headway distanc...
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This document was uploaded on 02/26/2014 for the course E 515 at University of Louisiana at Lafayette.
- Spring '13