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Dynamic programming with approximation function for nurse scheduling (2016)
Journal Article
Shi, P., & Landa-Silva, D. (2016). Dynamic programming with approximation function for nurse scheduling. Lecture Notes in Artificial Intelligence, 10122, doi:10.1007/978-3-319-51469-7_23

Although dynamic programming could ideally solve any combinatorial optimization problem, the curse of dimensionality of the search space seriously limits its application to large optimization problems. For example, only few papers in the literature h... Read More about Dynamic programming with approximation function for nurse scheduling.

An application programming interface with increased performance for optimisation problems data (2016)
Journal Article
Pinheiro, R. L., Landa-Silva, D., Qu, R., Constantino, A. A., & Yanaga, E. (in press). An application programming interface with increased performance for optimisation problems data. Journal of Management Analytics, 3(4), doi:10.1080/23270012.2016.1233514

An optimisation problem can have many forms and variants. It may consider different objectives, constraints, and variables. For that reason, providing a general application programming interface (API) to handle the problem data efficiently in all sce... Read More about An application programming interface with increased performance for optimisation problems data.

Decomposition techniques with mixed integer programming and heuristics for home healthcare planning (2016)
Journal Article
Laesanklang, W., & Landa-Silva, D. (2017). Decomposition techniques with mixed integer programming and heuristics for home healthcare planning. Annals of Operations Research, 256(1), https://doi.org/10.1007/s10479-016-2352-8

We tackle home healthcare planning scenarios in the UK using decomposition methods that incorporate mixed integer programming solvers and heuristics. Home healthcare planning is a difficult problem that integrates aspects from scheduling and routing.... Read More about Decomposition techniques with mixed integer programming and heuristics for home healthcare planning.

(1+1)-evolutionary gradient strategy to evolve global term weights in information retrieval (2016)
Book Chapter
Ibrahim, O. A. S., & Landa-Silva, D. (2016). (1+1)-evolutionary gradient strategy to evolve global term weights in information retrieval. In A. Gegov, P. Angelov, C. Jayne, & Q. Shen (Eds.), Advances in computational intelligence systems: contributions presented at the 16th UK Workshop on Computational Intelligence, September 7–9, 2016, Lancaster, UKSpringer. doi:10.1007/978-3-319-46562-3_25

In many contexts of Information Retrieval (IR), term weights play an important role in retrieving the relevant documents responding to users' queries. The term weight measures the importance or the information content of a keyword existing in the doc... Read More about (1+1)-evolutionary gradient strategy to evolve global term weights in information retrieval.

A Genetic Algorithm for a Workforce Scheduling and Routing Problem (2016)
Conference Proceeding
Algethami, H., Pinheiro, R. L., & Landa-Silva, D. (2016). A Genetic Algorithm for a Workforce Scheduling and Routing Problem

The Workforce Scheduling and Routing Problem refers to the assignment of personnel to visits across various geographical locations. Solving this problem demands tackling scheduling and routing constraints while aiming to minimise the total operationa... Read More about A Genetic Algorithm for a Workforce Scheduling and Routing Problem.

An investigation of heuristic decomposition to tackle workforce scheduling and routing with time-dependent activities constraints (2016)
Book
Laesanklang, W., Landa-Silva, D., & Castillo-Salazar, J. A. (in press). An investigation of heuristic decomposition to tackle workforce scheduling and routing with time-dependent activities constraints. In B. Vitoriano, & G. Parlier (Eds.), Operations research and enterprise systemsSpringer

This paper presents an investigation into the application of heuristic decomposition and mixed-integer programming to tackle workforce scheduling and routing problems (WSRP) that involve time dependent activities constraints. These constraints refer... Read More about An investigation of heuristic decomposition to tackle workforce scheduling and routing with time-dependent activities constraints.

Towards an efficient API for optimisation problems data (2016)
Conference Proceeding
Pinheiro, R. L., Landa-Silva, D., Qu, R., Yanaga, E., & Constantino, A. A. (2016). Towards an efficient API for optimisation problems data. In . S. Hammoudi, . L. Maciaszek, . M. M. Missikoff, O. Camp, & . J. Cordeiro (Eds.), Proceedings of the 18th International Conference on Enterprise Information Systems . Volume 2: ICEIS, 89-98. doi:10.5220/0005915800890098

The literature presents many application programming interfaces (APIs) and frameworks that provide state of the art algorithms and techniques for solving optimisation problems. The same cannot be said about APIs and frameworks focused on the problem... Read More about Towards an efficient API for optimisation problems data.

Hyper-volume evolutionary algorithm (2016)
Journal Article
Le, K. N., & Landa-Silva, D. (2016). Hyper-volume evolutionary algorithm

We propose a multi-objective evolutionary algorithm (MOEA), named the Hyper-volume Evolutionary Algorithm (HVEA). The algorithm is characterised by three components. First, individual fitness evaluation depends on the current Pareto front, specifical... Read More about Hyper-volume evolutionary algorithm.

Mixed integer programming with decomposition for workforce scheduling and routing with time-dependent activities constraints (2016)
Conference Proceeding
Laesanklang, W., Landa-Silva, D., & Castillo-Salazar, J. A. (2016). Mixed integer programming with decomposition for workforce scheduling and routing with time-dependent activities constraints

We present a mixed integer programming decomposition approach to tackle workforce scheduling and routing problems (WSRP) that involve time-dependent activities constraints. The proposed method is called repeated decomposition with conflict repair (RD... Read More about Mixed integer programming with decomposition for workforce scheduling and routing with time-dependent activities constraints.

Extended decomposition for mixed integer programming to solve a workforce scheduling and routing problem (2015)
Book Chapter
Laesanklang, W., Pinheiro, R. L., Algethami, H., & Landa-Silva, D. (2015). Extended decomposition for mixed integer programming to solve a workforce scheduling and routing problem. In G. H. Parlier, D. D. Werra, & B. Vitoriano (Eds.), Operations research and enterprise systems: 4th International Conference, ICORES 2015, Lisbon, Portugal, January 10-12, 2015: revised selected papersSpringer. doi:10.1007/978-3-319-27680-9_12

We propose an approach based on mixed integer programming (MIP) with decomposition to solve a workforce scheduling and routing problem, in which a set of workers should be assigned to tasks that are distributed across different geographical locations... Read More about Extended decomposition for mixed integer programming to solve a workforce scheduling and routing problem.

A Variable Neighbourhood Search for nurse scheduling with balanced preference satisfaction (2015)
Conference Proceeding
Constantino, A. A., Tozzo, E., Pinheiro, R. L., Landa-Silva, D., & Romão, W. (2015). A Variable Neighbourhood Search for nurse scheduling with balanced preference satisfaction

The nurse scheduling problem (NSP) is a combinatorial optimisation problem widely tackled in the literature. Recently, a new variant of this problem was proposed, called nurse scheduling problem with balanced preference satisfaction (NSPBPS). This pa... Read More about A Variable Neighbourhood Search for nurse scheduling with balanced preference satisfaction.

Term frequency with average term occurrences for textual information retrieval (2015)
Journal Article
Ibrahim, O., & Landa-Silva, D. (2016). Term frequency with average term occurrences for textual information retrieval. Soft Computing, 20(8), doi:10.1007/s00500-015-1935-7

In the context of Information Retrieval (IR) from text documents, the term-weighting scheme (TWS) is a key component of the matching mechanism when using the vector space model (VSM). In this paper we propose a new TWS that is based on computing the... Read More about Term frequency with average term occurrences for textual information retrieval.

A variable neighbourhood search for the workforce scheduling and routing problem (2015)
Book Chapter
Pinheiro, R. L., Landa-Silva, D., & Atkin, J. (2015). A variable neighbourhood search for the workforce scheduling and routing problem. In A. P. Engelbrecht, N. Pillay, A. Abraham, M. C. du Plessis, V. Snášel, & A. K. Muda (Eds.), Advances in nature and biologically inspired computing: proceedings of the 7th World Congress on Nature and Biologically Inspired Computing, NaBIC2015, in Pietermaritzburg, South Africa, held December 01-03, 2015Springer. doi:10.1007/978-3-319-27400-3_22

The workforce scheduling and routing problem (WSRP) is a combinatorial optimisation problem where a set of workers must perform visits to geographically scattered locations. We present a Variable Neighbourhood Search (VNS) metaheuristic algorithm to... Read More about A variable neighbourhood search for the workforce scheduling and routing problem.

A hybrid GRASP-VNS for Ship Routing and Scheduling Problem with Discretized Time Windows (2015)
Journal Article
Armas, J. D., Lalla-Ruiz, E., Expósito-Izquierdo, C., Landa-Silva, D., & Melián-Batista, B. (2015). A hybrid GRASP-VNS for Ship Routing and Scheduling Problem with Discretized Time Windows. Engineering Applications of Artificial Intelligence, 45, doi:10.1016/j.engappai.2015.07.013

This paper addresses the Ship Routing and Scheduling Problem with Discretized Time Windows. Being one of the most relevant and challenging problems faced by decision makers from shipping companies, this tramp shipping problem lies in determining the... Read More about A hybrid GRASP-VNS for Ship Routing and Scheduling Problem with Discretized Time Windows.

Analysis of objectives relationships in multiobjective problems using trade-off region maps (2015)
Conference Proceeding
Pinheiro, R. L., Landa-Silva, D., & Atkin, J. (2015). Analysis of objectives relationships in multiobjective problems using trade-off region maps

Understanding the relationships between objectives in many-objective optimisation problems is desirable in order to develop more effective algorithms. We propose a techniquefor the analysis and visualisation of complex relationships between many (thr... Read More about Analysis of objectives relationships in multiobjective problems using trade-off region maps.

A study of genetic operators for the Workforce Scheduling and Routing Problem (2015)
Conference Proceeding
Algethami, H., & Landa-Silva, D. (2015). A study of genetic operators for the Workforce Scheduling and Routing Problem

The Workforce Scheduling and Routing Problem (WSRP) is concerned with planning visits of qualified workers to different locations to perform a set of tasks, while satisfying each task time-window plus additional requirements such as customer/workers... Read More about A study of genetic operators for the Workforce Scheduling and Routing Problem.

Mixed integer programming with decomposition to solve a workforce scheduling and routing problem (2015)
Conference Proceeding
Laesanklang, W., Landa-Silva, D., & Castillo-Salazar, J. A. (2015). Mixed integer programming with decomposition to solve a workforce scheduling and routing problem

We propose an approach based on mixed integer programming (MIP) with decomposition to solve a workforce scheduling and routing problem, in which a set of workers should be assigned to tasks that are distributed across different geographical locations... Read More about Mixed integer programming with decomposition to solve a workforce scheduling and routing problem.

A greedy heuristic for workforce scheduling and routing with time-dependent activities constraints (2015)
Conference Proceeding
Castillo-Salazar, J. A., Landa-Silva, D., & Qu, R. (2015). A greedy heuristic for workforce scheduling and routing with time-dependent activities constraints

We present a greedy heuristic (GHI) designed to tackle five time-dependent activities constraints (synchronisation, overlap, minimum difference, maximum difference and minimum-maximum difference) on workforce scheduling and routing problems. These ty... Read More about A greedy heuristic for workforce scheduling and routing with time-dependent activities constraints.

A new weighting scheme and discriminative approach for information retrieval in static and dynamic document collections (2014)
Conference Proceeding
Ibrahim, O. A. S., & Landa-Silva, D. (2014). A new weighting scheme and discriminative approach for information retrieval in static and dynamic document collections

This paper introduces a new weighting scheme in information retrieval. It also proposes using the document centroid as a threshold for normalizing documents in a document collection. Document centroid normalization helps to achieve more effective inf... Read More about A new weighting scheme and discriminative approach for information retrieval in static and dynamic document collections.

Workforce scheduling and routing problems: literature survey and computational study (2014)
Journal Article
Castillo-Salazar, J. A., Landa-Silva, D., & Qu, R. (2016). Workforce scheduling and routing problems: literature survey and computational study. Annals of Operations Research, 239(1), doi:10.1007/s10479-014-1687-2

In the context of workforce scheduling, there are many scenarios in which personnel must carry out tasks at different locations hence requiring some form of transportation. Examples of these type of scenarios include nurses visiting patients at home,... Read More about Workforce scheduling and routing problems: literature survey and computational study.


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