Untitled

A Two-Stage Algorithm for School Bus Stop Location and Routing Problem With Walking Accessibility and Mixed Load

“…The number of ants, m, in each iteration is set to be the number of bus stops generated at stop location stage, n. The stops and schools are taken into consideration separately when it comes to service duration at each node. The pickup duration at each stop (in seconds) is calculated by t s i = 19.0 + 2.6 × d i , ∀i ∈ P + while the formula t s j = 29.0 + 1.9 × d j , ∀j ∈ P 0 is adopted to determine the drop off duration at each school [11]. Notice that each school can be visited by many buses with different number of students d j to drop off, leading to different drop off duration of different buses at a same school.…”

“…School bus problem is essentially a kind of pickup and delivery problem, while presenting its unique characteristic relative to traditional bus schedule [2]- [5], pickup and delivery problem [6], [7], and traditional vehicle routing problem [8]- [10]. Braca et al [11], Desrosiers et al [12], Park and Kim [13], and Ellegood et al [14] have reviewed the development of school bus problem. The school bus problem includes several sub-problems: data preparation, bus stop selection (student assignment to stops), bus route generation, school bell time adjustment, and route scheduling [12].…”

“…The school bus problem includes several sub-problems: data preparation, bus stop selection (student assignment to stops), bus route generation, school bell time adjustment, and route scheduling [12]. Researches abound in the single sub-problems, especially bus route generation [11], [13]- [17] while there are limited studies focused on standalone school bus stop selection problem [18]- [20] in which references [18], [19] considered stop location problem. Since we primarily focus on the school bus location and routing problem, the stop location problem is considered as a sub-problem and separated from stop selection.…”