D. CHIMBA ET AL. 303
Traffic Assignment
From O-D Survey From SUE Deviation (%)
Route A 24,600 28,000 13.8%
PR-153 15,400 12,000 22%
6. Conclusions
Thaper integrated the findings from origin-destination
(O-Dey and ststic userium in
routeation ste news propo the
townamo, Pu. Thsed nete is
ex
e town were deter-
minedm the O-D surv assignments
on thnew atesed-
ings from O-D survey.
ic Userium was th
to ork uitial volumes assigned
from O-D survey findings. Included in the SUE was tra-
s which is controlled by the free flow
ty, length of the link and si
assignment on new route was i
cr
[1]
ure Travelers to the United States by Income Level,” Jour-
e p
) survochar equilibapproach
reloc
of Co
udy. Th
erto Rico
route i
e propo
sed in
w rou
pected to capture diverted traffic currently using exist-
ing routes. The O-D provided the existing traffic pattern
and characteristics with respect to trip purposes, and the
percentages for internal and external trips. Percentages of
trips from major cities surrounding th
fro
e
ey. The initial trip
nd existing rous were ba on the find
Stochastr Equilib(SUE) en applied
the netwsing the intraffic
vel time on the link
speed, maximum capacignal
spacing density. Apart from link travel time, the utility
function of SUE contained other link measures of effec-
tiveness such as time spent in the vehicle (in-vehicle time
coefficient), congestion index and cost due to gasoline
consumption (cost coefficient). The gasoline cost consi-
dered vehicle fuel efficient of 20 miles/gallon, gasoline
price of $4.15/gallon and length of the link. All these link
characteristics were used to optimize the traveler choice
of the route.
Traffic assignment from the SUE was slightly different
from those initially assigned using O-D, indicating there
was optimization. The n-
eased by 13.8% from the one assigned using O-D while
assignment on the existing link was reduced by 22%. The
final optimized volumes were within capacity limits for
each link indicating successful optimization. The final
traffic assignment from SUE was used in the new route
design. The findings from this study showed the possible
benefit of integrating O-D with other trip assignment opti-
mization approaches. By integrating O-D survey with opti-
mization algorithms like UE or SUE can result in a well
balanced links which take into account all possible con-
strains.
REFERENCES
S. Jiang, B. Bai, G. Hong and J. O’Leary, “Understanding
Travel Expenditure Patterns: A Study of Japanese Pleas-
nal of Tourism Management, Vol. 25, No. 3, 2004, pp.
331-341.
doi:10.1016/S0261-5177(03)00141-9
[2] H. Alibabai and H. S. Mahmassani, “Dynamic Origin-
Destination Demand Estimation Using Turning Move-
ment Counts,” The 87th Annual Meeting of the Trans-
portation Research Board Proceedings, Washington DC,
2008.
[3] H. Spiess, “A Maximum Likelihood Model for Estimat-
ing Origin-Destination Matrices,” Transportation Re-
search, Vol. 21, No. 5, 1987, pp. 395-412.
doi:10.1016/0191-2615(87)90037-3
[4] M. Hazelton, “Some Comments on Origin-Destination
Matrix Estimation,” Transportation Research Part A: Po-
licy and Practice, Vol. 37, No. 10, 2003, pp. 811-822.
doi:10.1016/S0965-8564(03)00044-2
amic Traffic Modeling [5] S. Han, “Dynand Dynamic Sto-
chastic User Equilibrium Assignment for General Road
Networks,” Transportation Research Part B: Methodo-
logical, Vol. 37, No. 3, 2003, pp. 225-249.
doi:10.1016/S0191-2615(02)00009-7
[6] M. Hazelton, “Estimation of Origin-Destination Matrices
from Link Flows on Uncongested Networks,” Transpor-
tation Research, Vol. 34, No. 7, 2000, pp. 549-566.
doi:10.1016/S0191-2615(99)00037-5
[7] K. Jeornsten and S. Wallace, “Overcoming the (Apparent)
Problem of Inconsistency in Origin-Destination Matrix
Estimations,” Tran sportation Science, Vol. 27, No. 4, 1993,
pp. 374-380. doi:10.1287/trsc.27.4.374
[8] H. Lo., N. Zhang and W. Lam, “Estimation
Destination Matrix with Random L
of an Origin-
ink Choice Propor-
tions: A Statistical Approach,” Transportation Research,
Vol. 30, No. 4, 1996, pp. 309-324.
doi:10.1016/0191-2615(95)00036-4
[9] M. Hazelton and M. Gordon, “Estimation of Origin-Desti-
ion,” Trans-
gical, Vol. 32, No.
nation Trip Matrices from Link Counts,” Proceedings of
the 2002 European Transport Conference, London, 2002.
[10] H. Yang and J. Zhou, “Optimal Traffic Counting Loca-
tions for Origin-Destination Matrix Estimat
portation Research Part B: Methodolo
2, 1998, pp. 109-126.
doi:10.1016/S0191-2615(97)00016-7
[11] J. Hu, L. Yang, L. Kong and Y. Yang, “Urban M
Traffic Flow Considering the Influenc
ixed
e by Origin-Desti-
nation of Public Transportation,” Journal of Transporta-
tion Systems Engineering and Information Technology,
Vol. 11, No. 1, 2011, pp. 102-107.
doi:10.1016/S1570-6672(10)60107-9
[12] S. Clark and P. Watling, “Sensitivity Analysis of the Pro-
bit-Based Stochastic User Equilibrium Assignment Mo-
del,” Transportation Research Part B: Methodological,
Vol. 36, No. 7, 2002, pp 617-635.
doi:10.1016/S0191-2615(01)00021-2
[13] Y. Lim and B. Heydecker, “Dynamic Departure Time and
Stochastic User Equilibrium Assignment,” Transportation
Research Part B: Methodological, Vol. 39, No. 2, 2005,
pp. 97-118. doi:10.1016/j.trb.2003.08.003
[14] A. Nielsen, D. Frederiksen and N. Simonsen, “Stochastic
User Equilibrium Traffic Assignment with Turn-Delays
Copyright © 2012 SciRes. JTTs