Heuristics are here to help your online vehicle scheduling

Salhi, Saïd; Currie, Robert H.

doi:10.1057/ori.2008.7

Cited by 6 publications

(1 citation statement)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is well known that routing problems are difficult to solve optimally and that heuristics offer reasonably good solutions within relatively short computation times (see, e.g., Salhi and Currie, 2009). However, it is not the intention of this paper to describe a new solution method for the model but rather to make use of the proposed model in obtaining solutions that improve upon the current practice.…”

Section: Resultsmentioning

confidence: 99%

Look, here comes the library van! Optimising the timetable of the mobile library service on the Isle of Wight

2011

View full text Add to dashboard Cite

This paper describes an approach taken to optimise the timetable of the mobile library service operating on the Isle of Wight. The mobile library visits over 90 communities on the island, offering books, DVDs, videos and CDs and operates on a periodic timetable. The optimisation problem is formulated as a multiple travelling salesmen model with additional time-balancing constraints on route durations. The paper also shows ways in which data required for the model, in particular travel times, was gathered and discusses practical issues arising in preprocessing the data to fit the purposes of the case study. The model is used to produce an improved timetable over the current one that implies driving time reductions of up to 25% and yields routes that are better balanced in terms of time spent on the visits made each day. The model is also used to test various scenarios differing with respect to the number of locations visited and days over which the service operates.

show abstract

Section: Resultsmentioning

confidence: 99%

Look, here comes the library van! Optimising the timetable of the mobile library service on the Isle of Wight

2011

View full text Add to dashboard Cite

show abstract

An adaptive variable neighbourhood search approach for the dynamic vehicle routing problem

Sze,

Salhi,

Wassan

2024

Computers & Operations Research

View full text Add to dashboard Cite

Asymptotic performance of the non-forced idle time scheduling policies in the presence of variable demand for resources

Radovanović

Stein

2008

2008 46th Annual Allerton Conference on Communication, Control, and Computing

View full text Add to dashboard Cite

A fundamental scheduling problem is to schedule a set of jobs on a set of machines so that as many jobs as possible can be scheduled while respecting the resource constraints on each machine. A further complication in many computer systems is that scheduling decisions must be made on-line, that is, as soon as job arrives it must either be scheduled or rejected. Many practical systems and algorithms schedule jobs in such a way that loads on machines tend to be balanced. However, in case when job requests are highly variable, such scheduling systems do not necessarily result in a good performance. If loads are balanced then when large jobs arrive, there may not be any "holes" large enough to hold them, thereby resulting in increased queueing delays and overall job sojourn times in the system. In this paper, we focus on addressing the job assignment problem in an on-line loss system framework, i.e., when a job arrives, it gets scheduled to a particular machine using a certain scheduling policy or, if there are not enough available resources on any of the machines, the incoming job is lost. This type of scheduling is often called Non-Forced Idle Time Scheduling and includes many common policies, including Best Fit, First Fit and Worst Fit.In this paper, we use compound point processes to capture stochastic variability in the request process, we derive simple asymptotic estimates for the job loss rate in these scheduling systems. Furthermore, we derive the asymptotic lower bound for the job loss rate by comparing it to the performance of a single large machine and derive an asympotic average case competitive ratio for the class of analyzed Non-forced Idle Time Scheduling policies. Although our proofs are asymptotic, we perform experiments which show an excellent match between simulation results and theoretical performance bounds, even for relatively small resource capacities and large values of measured loss rates.

show abstract

Heuristics are here to help your online vehicle scheduling

Cited by 6 publications

References 7 publications

Look, here comes the library van! Optimising the timetable of the mobile library service on the Isle of Wight

Look, here comes the library van! Optimising the timetable of the mobile library service on the Isle of Wight

An adaptive variable neighbourhood search approach for the dynamic vehicle routing problem

Asymptotic performance of the non-forced idle time scheduling policies in the presence of variable demand for resources

Contact Info

Product

Resources

About