Environmental Engineering Reference
In-Depth Information
Table 5 Comparisons among 8, 12, and 24 available periods
Problem instance
Number of available periods
Maximum percentage reduction
compared to bench mark (%)
8
12
48
1
140,927
144,287
148,813
5.30
182,461
188,494
191,171
4.56
2
243,862
249,521
256,050
4.76
3
4
222,552
229,106
234,068
4.92
293,058
300,632
309,165
5.21
5
6
356,993
362,131
369,870
3.48
7
356,140
363,725
371,792
4.21
436,081
441,106
452,695
3.67
8
9
599,750
609,658
622,051
3.59
approximately 4 % of emissions. If the number of available periods decreases,
more reduction of emissions is achieved. However, it is not convenient for ship-
ping companies if number of available periods is much reduced because it will
limit the selection of picking up period. In our opinion, 8 or 12 available periods
is reasonable. Note that this is the percentage of reduction emissions for one block
at a container terminal. Considering the activity of a terminal in a year, we can
see that a huge reduction in emissions. This indicates that the truck emissions can
be significantly reduced, if the terminal operator controls the truck arrival times
by cutting one-fourth or one-sixth of the available container pick-up periods. In
many container terminals, TAS system is mainly used for export containers due
to the fact that it is more critical to reduce the time for loading container to ves-
sel. Furthermore, TAS system is allowed 24 available periods in practical use.
Therefore, implementing the proposed approach is more effective at ports that do
not use TAS for import containers currently.
6 Summary
In this study, we considered import-related truck emission reduction at container
terminal. A mathematical model which combines deterministic and stochastic fac-
tors is formulated. A solution algorithm is proposed to solve the problem in which
a simulation-based GA is developed. Several experiments are conducted to show
the performance of proposed algorithm. Throughout these experiments, it can be
found that the emission from truck engine idling could be significantly reduced
by providing appropriate service time for picking up containers. For example the
emission is reduced about 4 % if the available periods are limited to either 8 or
12 h instead of 48 h.
The main contributions of this study are to propose a methodology to reduce
the emission at container terminal by using TAS and to develop a mathematical
 
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