Der-Horng Lee

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Short-term traffic flow prediction has long been regarded as a critical concern for intelligent transportation systems. On the basis of many existing prediction models, each having good performance only in a particular period, an improved approach is to combine these single predictors together for prediction in a span of periods. In this paper, a neural(More)
The quay crane scheduling problem studied in this paper is to determine a handling sequence of holds for quay cranes assigned to a container vessel considering interference between quay cranes. This paper provides a mixed integer programming model for the considered quay crane scheduling problem that is NP-complete in nature. A genetic algorithm is proposed(More)
This paper presents a novel multiagent approach to automating taxi dispatch that services current bookings in a distributed fashion. The existing system in use by a taxi operator in Singapore and elsewhere, attempts to increase customer satisfaction locally, by sequentially dispatching nearby taxis to service customers. The proposed dispatch system attempts(More)
Rapid tranit systems are the most important public transportation service modes in many large cities around the world. Hence, its service reliability is of high importance for government and transit agencies. Despite taking all the necessary precautions, disruptions cannot be entirely prevented but what transit agencies can do is to prepare to respond to(More)
This research involves the study of the existing taxi dispatch system employed by taxi operators in Singapore to handle current bookings. This dispatch system adopts the Global Positioning Systems (GPS), and is based on the nearest-coordinate method, i.e. the taxi assigned for each booking is the one with the shortest, direct, straight-line distance to the(More)
Understanding of the mechanisms driving our daily face-to-face encounters is still limited; the field lacks large-scale datasets describing both individual behaviors and their collective interactions. However, here, with the help of travel smart card data, we uncover such encounter mechanisms and structures by constructing a time-resolved in-vehicle social(More)
An empirical and comparative evaluation of multiagent taxi dispatch with extended (E) runtime taxi availability is presented. A taxi in operation is said to be E-runtime available if it has a passenger alighting in ¿x > 0 minutes' time or is empty, but has no new committed taxi request to service next. In a multiagent architecture, we consider a new(More)
Recent research has demonstrated and established the viability of applying path-based algorithms to the traffic equilibrium problem in reasonably large networks. Much of the attention has been focused on two particular algorithms: the disaggregate simplicial decomposition (DSD) algorithm and the gradient projection (GP) algorithm. The purpose of this paper(More)
This research involves a study of the existing taxi dispatch system employed by taxi operators in Singapore. Based on the booking surcharges, there are generally two categories of taxi bookings, current and advance. Current bookings are requests that taxi should reach the customer immediately or within half an hour, and advance bookings are requests made at(More)