Abstract
The Dial-a-Ride problem may contain various constraints for pickup-delivery requests, such as time windows and ride time constraints. For a tour, given as a sequence of pickup and delivery stops, there exist polynomial time algorithms to nd a schedule respecting these constraints, provided that there exists one. However, if no feasible schedule exists, the natural question is to nd a schedule minimising constraint violations. We model a generic xed-sequence scheduling problem, allowing lateness and ride time violations with linear penalty functions and prove its APX-hardness. We also present an approach leading to a polynomial time algorithm if only the time window constraints can be violated (by late visits). Then, we show that the problem can be solved in polynomial time if all the ride time constraints are bounded by a constant. Lastly, we give a polynomial time algorithm for the instances where all the pickups precede all the deliveries in the sequence of stops.
Original language | English |
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Title of host publication | Algorithms and Complexity |
Subtitle of host publication | 11th International Conference, CIAC 2019, Rome, Italy, May 27–29, 2019, Proceedings |
Editors | Pinar Heggernes |
Publisher | Springer |
Pages | 149-160 |
Number of pages | 12 |
ISBN (Electronic) | 978-3-030-17402-6 |
ISBN (Print) | 978-3-030-17401-9 |
DOIs | |
Publication status | Published - 1 May 2019 |
Event | 11th International Conference on Algorithms and Complexity - Rome, Italy Duration: 27 May 2019 → 29 May 2019 http://easyconferences.eu/ciac2019/ |
Publication series
Name | Lecture Notes in Computer Science |
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Publisher | Springer |
Volume | 11485 |
ISSN (Print) | 0302-9743 |
ISSN (Electronic) | 1611-3349 |
Conference
Conference | 11th International Conference on Algorithms and Complexity |
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Abbreviated title | CIAC |
Country/Territory | Italy |
City | Rome |
Period | 27/05/19 → 29/05/19 |
Internet address |
Keywords
- dial-a-ride
- time windows
- ride times
- NPhardness
- Vehicle Routing Problem
- scheduling