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Number of items: 77.

Lewis, Rhyd

and Palmer, Geraint

2025. GCol: A high-performance Python library for graph colouring. The Journal of Open Source Software 10 (108) , 7871. 10.21105/joss.07871

Lewis, Rhyd

and Bonnet, Louis 2025. Exact algorithms in bar nesting: How to cut general items from linear stocks so that wastage is minimised. Computers & Industrial Engineering 200 , 110838. 10.1016/j.cie.2024.110838

Shekarriz, Mohammad H., Thiruvady, Dhananjay, Nazari, Asef and Lewis, Rhyd

2025. Soft happy colourings and community structure of networks. Computers and Operations Research 174 , 106893. 10.1016/j.cor.2024.106893

Corcoran, Padraig

and Lewis, Rhyd

2025. A user-centric model of connectivity in street networks. Computers and Operations Research 173 , 106846. 10.1016/j.cor.2024.106846

Lewis, Rhydian

2025. GCol: Official documentation of the Python library for graph coloring. [Documentation]. readthedocs.com. Available at: https://readthedocs.org/projects/gcol/downloads/pd...

Corcoran, Padraig

and Lewis, Rhydian

2025. An analysis of the correctness and computational complexity of path planning in Payment Channel Networks. The Journal of Financial Technology

Corcoran, Padraig

and Lewis, Rhydian

2024. Path planning in payment channel networks with multi-party channels. Distributed Ledger Technologies: Research and Practice 10.1145/3702248

Lewis, Rhydian

2024. Cardiff: Software solutions for designing school transport systems. [Online]. Delft: Website of the European Consortium for Mathematics in Industry. Available at: https://ecmiindmath.org/2024/10/24/cardiff-softwar...

Lewis, Rhyd

and Corcoran, Padraig

2024. Fast algorithms for computing fixed-length round trips in real-world street networks. SN Computer Science 5 (7) , 868. 10.1007/s42979-024-03223-3

Hambly, Daniel, Lewis, Rhydian

and Corcoran, Padraig

2024. Determining fixed-length paths in directed and undirected edge-weighted graphs. Presented at: Symposium on Experimental Algorithms (SEA) 2024, Vienna, Austria, 24-26 July 2024. Published in: Liberti, Leo ed. 22nd International Symposium on Experimental Algorithms (SEA 2024). Leibniz International Proceedings in Informatics (LIPIcs) , vol.301 15.1-15.11. 10.4230/LIPIcs.SEA.2024.15

Dijkstra, Lukas, Gagarin, Andrei

, Corcoran, Padraig

and Lewis, Rhyd

2024. Digraphs and k-domination models for facility location problems in road networks: Greedy heuristics. Presented at: International Network Optimization Conference 2024, Dublin, Ireland, 11-13 March 2024. Proceedings of the 11th International Network Optimization Conference (INOC). OpenProceedings, pp. 22-27. 10.48786/inoc.2024.05

Corcoran, Padraig

and Lewis, Rhyd

2024. Optimisation of livestock routing on farms. Computers & Industrial Engineering 188 , 109882. 10.1016/j.cie.2024.109882

Bonnet, Louis and Lewis, Rhydian

2024. Exact bar nesting with industrial symmetry considerations. Presented at: 25e Congres Annuel de la Societe Francaise de Recherche Operationnelle et d'Aide a la Decision, Amiens, France, 4-7 March, 2024.

Lewis, R.

, Corcoran, P.

and Gagarin, A.

2023. Methods for determining cycles of a specific length in undirected graphs with edge weights. Journal of Combinatorial Optimization 46 , 29. 10.1007/s10878-023-01091-w

Corcoran, Padraig

and Lewis, Rhyd

2023. A navigability entropy model for street networks. Environment and Planning B: Urban Analytics and City Science 50 (8) , pp. 2171-2186. 10.1177/23998083231170191

Lewis, Rhydian

2023. A comparison of Dijkstra's Algorithm using fibonacci heaps, binary heaps, and self-balancing binary trees. [Online]. Preprint repository: ArXiv. Available at: https://arxiv.org/abs/2303.10034

Thiruvady, Dhananjay and Lewis, Rhyd

2022. Recombinative approaches for the maximum happy vertices problem. Swarm and Evolutionary Computation 75 , 101188. 10.1016/j.swevo.2022.101188

Monique, Sciortino, Lewis, Rhydian

and Thompson, Jonathan 2022. A school bus routing heuristic algorithm allowing heterogeneous fleets and bus stop selection. SN Computer Science 4 , 74. 10.1007/s42979-022-01466-6

Hawa, Asyl, Lewis, Rhydian

and Thompson, Jonathan 2022. Exact and approximate methods for the score-constrained packing problem. European Journal of Operational Research 302 (3) , pp. 847-859. 10.1016/j.ejor.2022.01.028

Lewis, R.

and Carroll, F. 2022. Exact algorithms for finding fixed-length cycles in edge-weighted graphs. Presented at: 2022 International Conference on Computer Communications and Networks (ICCCN), 25-28 July 2022. 2022 International Conference on Computer Communications and Networks (ICCCN). IEEE, 10.1109/ICCCN54977.2022.9868939

Carroll, Fiona and Lewis, Rhyd

2022. Internet security aesthetics: can internet transparency afford social trust? Presented at: 2022 International Conference on Computer Communications and Networks (ICCCN), 25-28 July 2022. 2022 International Conference on Computer Communications and Networks (ICCCN). IEEE, 10.1109/ICCCN54977.2022.9868880

Lewis, Rhydian

and Corcoran, Padraig

2022. Finding fixed-length circuits and cycles in undirected edge-weighted graphs: an application with street networks. Journal of Heuristics 28 , pp. 259-285. 10.1007/s10732-022-09493-5

Lewis, Rhydian

2021. DSatur algorithm for graph coloring. [Online]. Geeks for Geeks. Available at: https://www.geeksforgeeks.org/dsatur-algorithm-for...

Lewis, R. M. R.

2021. Guide to graph colouring. Texts in Computer Science, Springer, Cham. 10.1007/978-3-030-81054-2

Lewis, R.

2021. Finding attractive exercise circuits in street maps. Presented at: 29th Annual GIS Research UK Conference (GISRUK 2021), Cardiff, Wales, 14-16 April 2021. 10.5281/zenodo.4665508

Lewis, R.

, Thiruvady, D. and Morgan, K. 2021. The maximum happy induced subgraph problem: bounds and algorithms. Computers and Operations Research 126 , 105114. 10.1016/j.cor.2020.105114

Sciortino, Monique, Lewis, Rhyd

and Thompson, Jonathan 2021. A heuristic algorithm for school bus routing with bus stop selection. Presented at: EvoCOP 2021, Seville, Spain, Apr 2021. Published in: Zarges, Christine and Verel, Sébastien eds. Evolutionary Computation in Combinatorial Optimization. Lecture Notes in Computer Science. Lecture Notes in Computer Science/Theoretical Computer Science and General Issues , vol.12692 Springer Verlag, 10.1007/978-3-030-72904-2_13

Kheiri, Ahmed, Lewis, Rhydian

, Thompson, Jonathan and Harper, Paul

2021. Constructing operating theatre schedules using partitioned graph colouring techniques. Health Systems 10 (4) , pp. 286-297. 10.1080/20476965.2020.1796530

Thiruvady, Dhananjay, Lewis, Rhyd

and Morgan, Kerri 2020. Tackling the maximum happy vertices problem in large networks. 4OR: A Quarterly Journal of Operations Research 18 , pp. 507-527. 10.1007/s10288-020-00431-4

Padungwech, Wasin

, Thompson, Jonathan and Lewis, Rhyd

2020. Effects of update frequencies in a dynamic capacitated arc routing problem. Networks 76 (4) , pp. 522-538. 10.1002/net.21990

Lewis, Rhyd

2020. Cite or be damned: some thoughts on reviewer-coerced citation. [Online]. Scientists are Humans. Available at: http://rhydlewis.eu/papers/ReviewerCoercedCitation...

Lewis, Rhyd

2020. Editorial for the special issue on “Algorithms for graphs and networks”. Algorithms 13 (11) , p. 292. 10.3390/a13110292

Lewis, Rhyd

2020. Algorithms for finding shortest paths in networks with vertex transfer penalties. Algorithms 13 (11) , 269. 10.3390/a13110269

Lewis, Rhyd

2020. A shortest path algorithm for graphs featuring transfer costs at their vertices. Presented at: International Conference on Computational Logistics, Enschede, The Netherlands, 28–30 Sept 2020. Computational Logistics. Lecture Notes in Computer Science. , vol.12433 Springer Verlag, pp. 539-552. 10.1007/978-3-030-59747-4_35

Lewis, Rhyd

2020. A heuristic algorithm for finding attractive fixed-length circuits in street maps. Presented at: International Conference on Computational Logistics, Enschede, The Netherlands, 28–30 Sept 2020. Computational Logistics. Lecture Notes in Computer Science. , vol.12433 Springer Verlag, pp. 384-395. 10.1007/978-3-030-59747-4_25

Lewis, Rhyd

, Anderson, Tom and Carroll, Fiona 2020. Can school enrolment and performance be improved by maximizing students' sense of choice in elective subjects? Journal of Learning Analytics 7 (1) , pp. 75-87. 10.18608/jla.2020.71.6

Lewis, Rhyd

2020. Five degrees of separation from De Niro - charting the social networks of movie stars. The Conversation

Lewis, Rhyd

2020. Who is the centre of the movie universe? Using python and networkX to analyse the social network of movie stars. [Online]. arXiv. Available at: https://arxiv.org/abs/2002.11103

Neis, Paulo and Lewis, Rhydian

2020. Evaluating the influence of parameter setup on the performance of heuristics for the graph colouring problem. International Journal of Metaheuristics 7 (4) , pp. 352-378.

Lewis, R.

, Thiruvady, D. and Morgan, K. 2019. Finding happiness: an analysis of the maximum happy vertices problem. Computers and Operations Research 103 10.1016/j.cor.2018.11.015

Lewis, Rhyd

2019. Want to mislead and confuse? use statistics! [Online]. Scientists are Humans. Available at: http://rhydlewis.eu/papers/statsArticle.pdf

Hawa, Asyl L., Lewis, Rhyd

and Thompson, Jonathan M. 2018. Heuristics for the score-constrained strip-packing problem. Presented at: COCOA 2018: International Conference on Combinatorial Optimization and Applications, Atlanta, GA, USA, 15-17 December 2018. Published in: Kim, Donghyun, Uma, R. N. and Zelikovsky, Alexander eds. Combinatorial Optimization and Applications: 12th International Conference, COCOA 2018, Atlanta, GA, USA, December 15-17, 2018, Proceedings. Lecture Notes in Computer Science , vol.11346 Springer Verlag, p. 449. 10.1007/978-3-030-04651-4_30

Lewis, Rhydian

2018. Two example optimisation problems from the world of education. Presented at: OR Society Annual Conference (OR60), Lancaster, UK, 11-13 Sep 2018.

Lewis, Rhyd

and Smith-Miles, K. 2018. A heuristic algorithm for finding cost-effective solutions to real-world school bus routing problems. Journal of Discrete Algorithms 52-53 , pp. 2-17. 10.1016/j.jda.2018.11.001

Hardy, Bradley, Lewis, Rhyd

and Thompson, Jonathan 2018. Tackling the edge dynamic graph colouring problem with and without future adjacency information. Journal of Heuristics 24 , pp. 321-343. 10.1007/s10732-017-9327-z

Lewis, Rhydian

, Smith-Miles, Kate and Phillips, Kyle 2018. The school bus routing problem: An analysis and algorithm. Presented at: IWOCA 2017: 28th International Workshop on Combinatorial Algorithms, Newcastle, NSW, Australia, 17-21 July 2017. Published in: Brankovic, Ljiljana, Ryan, Joe and Smyth, William F. eds. Combinatorial Algorithms: 28th International Workshop, IWOCA 2017, Newcastle, NSW, Australia, July 17-21, 2017, Revised Selected Papers. Lecture Notes in Computer Science Springer, pp. 287-298. 10.1007/978-3-319-78825-8_24

Lewis, Rhyd

and Holborn, Penny 2017. How to pack trapezoids: exact and evolutionary algorithms. IEEE Transactions on Evolutionary Computation 21 (3) , pp. 463-476. 10.1109/TEVC.2016.2609000

Lewis, Rhyd

and Carroll, Fiona 2016. Creating seating plans: a practical application. Journal of the Operational Research Society 67 (11) , pp. 1353-1362. 10.1057/jors.2016.34

Padungwech, Wasin

, Thompson, Jonathan and Lewis, Rhyd

2016. Investigating edge-reordering procedures in a tabu search algorithm for the capacitated arc routing problem. Presented at: HM 2016: International Workshop on Hybrid Metaheuristics, Plymouth, UK, 8-10 June 2016. Published in: Blesa, Maria J., Blum, Christian and Cangelosi, Angelo eds. Hybrid Metaheuristics: 10th International Workshop, HM 2016, Plymouth, UK, June 8-10, 2016, Proceedings. Lecture Notes in Computer Science. Lecture Notes in Computer Science , vol.9668 Cham: Springer, pp. 62-74. 10.1007/978-3-319-39636-1_5

Hardy, Bradley, Lewis, Rhyd

and Thompson, Jonathan Mark 2016. Modifying colourings between time-steps to tackle changes in dynamic random graphs. Presented at: EvoCOP 2016: European Conference on Evolutionary Computation in Combinatorial Optimization, Porto, Portugal, 30 March - 1 April 2016. Published in: Chicano, Francisco, Hu, Bin and Garcia-Sanchez, Pablo eds. Evolutionary Computation in Combinatorial Optimization: 16th European Conference, EvoCOP 2016, Porto, Portugal, March 30 – April 1, 2016, Proceedings. Lecture Notes in Computer Science. , vol.9595 Springer, pp. 186-201. 10.1007/978-3-319-30698-8_13

Kheiri, Ahmed

, Özcan, Ender, Lewis, Rhydian

and Thompson, Jonathan 2016. A Sequence-based selection hyper-heuristic: a case study in nurse rostering. Presented at: PATAT 2016: 11th International Conference on the Practice and Theory of Automated Timetabling, Udine, Italy, 23-26 August 2016. Published in: Burke, Edmund K., Di Gaspero, Luca, Özcan, Ender, McCollum, Barry and Schaerf, Andrea eds. PATAT 2016: Proceedings of the 11th International Conference of the Practice and Theory of Automated Timetabling. pp. 503-505.

Lewis, Rhydian

2016. Graph colouring: an ancient problem with modern applications. Impact 3 (1) , pp. 47-50. 10.1080/2058802X.2016.11963998

Lewis, R. M. R.

2015. A guide to graph colouring: algorithms and applications. Springer. 10.1007/978-3-319-25730-3

Lewis, R.

and Thompson, J. 2015. Analysing the effects of solution space connectivity with an effective metaheuristic for the course timetabling problem. European Journal of Operational Research 240 (3) , pp. 637-648. 10.1016/j.ejor.2014.07.041

Rowse, Elizabeth Louise, Lewis, Rhydian

, Harper, Paul Robert

and Thompson, Jonathan Mark 2015. Applying set partitioning methods in the construction of operating theatre schedules. Presented at: International Conference on Theory and Practice in Modern Computing 2015, Las Palmas de Gran Canaria, Spain, 22-24 July 2015.

Lewis, Rhyd

2015. Graph coloring and recombination. Kacprzyk, J. and Pedrycz, W., eds. Springer Handbook of Computational Intelligence, Springer, pp. 1239-1254.

Smith-Miles, Kate, Baatar, Davaatseren, Wreford, Brendan and Lewis, Rhyd

2014. Towards objective measures of algorithm performance across instance space. Computers & Operations Research 45 , pp. 12-24. 10.1016/j.cor.2013.11.015

John, Matthew P., Mumford, Christine L.

and Lewis, Rhyd

2014. An improved multi-objective algorithm for the urban transit routing problem. Presented at: EvoCOP 2014: 14th European Conference on Evolutionary Computation in Combinatorial Optimization, Granada, Spain, 23-25 April 2014. Published in: Blum, Christian and Ochoa, Gabriela eds. Evolutionary Computation in Combinatorial Optimisation: 14th European Conference, EvoCOP 2014, Granada, Spain, April 23-25, 2014, Revised Selected Papers. Lecture Notes in Computer Science. Lecture Notes in Computer Science , vol.8600 Springer, pp. 49-60. 10.1007/978-3-662-44320-0_5

Cooper, Ian

, John, Matthew P., Lewis, Rhydian

, Mumford, Christine Lesley

and Olden, Andrew 2014. Optimising large scale public transport network design problems using mixed-mode parallel multi-objective evolutionary algorithms. Presented at: IEEE Congress on Evolutionary Computation, Beijing, China, 6 - 11 July 2014. Evolutionary Computation (CEC). Proceedings of the 2014 IEEE Congress on Evolutionary Computation. IEEE, pp. 2841-2848. 10.1109/CEC.2014.6900362

Lewis, Rhydian

and Carroll, Fiona 2013. The "engaged" interaction: important considerations for the HCI design and development of a web application for solving a complex combinatorial optimization problem. World Journal of Computer Application and Technology 1 (3) , pp. 75-82.

Lewis, Rhyd

, Thompson, Jonathan Mark, Mumford, Christine Lesley

and Gillard, Jonathan William

2012. A wide-ranging computational comparison of high-performance graph colouring algorithms. Computers & Operations Research 39 (9) , pp. 1933-1950. 10.1016/j.cor.2011.08.010

Song, Xiang

, Lewis, Rhyd

, Thompson, Jonathan Mark and Wu, Yue 2012. An incomplete m-exchange algorithm for solving the large-scale multi-scenario knapsack problem. Computers & Operations Research 39 (9) , pp. 1988-2000. 10.1016/j.cor.2011.09.012

Lewis, Rhyd

2012. A time-dependent metaheuristic algorithm for post enrolment-based course timetabling. Annals of Operations Research 194 (1) , pp. 273-289. 10.1007/s10479-010-0696-z

Holborn, Penny Louise, Thompson, Jonathan Mark and Lewis, Rhyd

2012. Combining heuristic and exact methods to solve the vehicle routing problem with pickups, deliveries and time windows. Presented at: EvoCOP 2012: 12th European Conference on Evolutionary Computation in Combinatorial Optimization, Malaga, Spain, 11-13 April 2012. Published in: Hao, J. K. and Middendorf, M. eds. Evolutionary Computation in Combinatorial Optimization: 12th European Conference, EvoCOP 2012, Málaga, Spain, April 11-13, 2012. Proceedings. Lecture Notes in Computer Science. Lecture Notes in Computer Science , vol.7245 Springer Verlag, pp. 63-74. 10.1007/978-3-642-29124-1_6

Lewis, Rhyd

, Song, Xiang

, Dowsland, Kathryn Anne and Thompson, Jonathan Mark 2011. An investigation into two bin packing problems with ordering and orientation implications. European Journal of Operational Research 213 (1) , pp. 52-65. 10.1016/j.ejor.2011.03.016

Lewis, Rhyd

and Thompson, Jonathan Mark 2011. On the application of graph colouring techniques in round-robin sports scheduling. Computers & Operations Research 38 (1) , pp. 190-204. 10.1016/j.cor.2010.04.012

Lewis, Rhyd

and Pullin, Emma J. 2011. Revisiting the restricted growth function genetic algorithm for grouping problems. Evolutionary Computation 19 (4) , pp. 693-704. 10.1162/EVCO_a_00040

Song, Xiang

, Chu, C. B., Lewis, Rhyd

, Nie, Y. Y. and Thompson, Jonathan Mark 2010. A worst case analysis of a dynamic programming-based heuristic algorithm for 2D unconstrained guillotine cutting. European Journal of Operational Research 202 (2) , pp. 368-378. 10.1016/j.ejor.2009.05.047

Lewis, Rhyd

2009. A general-purpose hill-climbing method for order independent minimum grouping problems: A case study in graph colouring and bin packing. Computers & Operations Research 36 (7) , pp. 2295-2310. 10.1016/j.cor.2008.09.004

McCollum, B., Schaerf, A., Paechter, B., McMullan, P., Lewis, Rhyd

, Parkes, A. J., Gaspero, L. D., Qu, R. and Burke, E. K. 2009. Setting the Research Agenda in Automated Timetabling: The Second International Timetabling Competition. INFORMS Journal on Computing 22 (1) , pp. 120-130. 10.1287/ijoc.1090.0320

Lewis, Rhydian

, Paechter, Ben and McCollum, Barry 2007. Post enrolment based course timetabling: a description of the problem model used for track two of the second International Timetabling Competition. [Working Paper]. Cardiff Working Papers in Accounting and Finance, Cardiff: Cardiff University.

Lewis, Rhyd

and Paechter, Ben 2007. Finding feasible timetables using group-based operators. IEEE Transactions on Evolutionary Computation 11 (3) , pp. 397-413. 10.1109/TEVC.2006.885162

Lewis, Rhyd

2007. A survey of metaheuristic-based techniques for university timetabling problems. OR Spectrum 30 (1) , pp. 167-190. 10.1007/s00291-007-0097-0

Lewis, Rhyd

2007. Metaheuristics can solve sudoku puzzles. Journal of Heuristics 13 (4) , pp. 387-401. 10.1007/s10732-007-9012-8

Lewis, Rhyd

2007. On the combination of constraint programming and stochastic search: the Sudoku case. Hybrid Metaheuristics, Lecture Notes in Computer Science, vol. 4771. Springer, pp. 96-107. (10.1007/978-3-540-75514-2_8)

Lewis, Rhyd

, Paechter, Ben and Rossi-Doria, Olivia 2007. Metaheuristics for university course timetabling. Dahal, Keshav P., Tan, Kay Chen and Cowling, Peter I., eds. Evolutionary Scheduling, Studies in Computational Intelligence, vol. 49. Springer, pp. 237-272. (10.1007/978-3-540-48584-1_9)

Lewis, Rhyd

and Paechter, Ben 2005. Application of the grouping genetic algorithm to university course timetabling. Lecture Notes in Computer Science 3448 , pp. 144-153. 10.1007/978-3-540-31996-2_14

This list was generated on Thu Oct 30 11:11:33 2025 GMT.