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- Conceptual multi-agent system design for distributed scheduling systemsPublication . Alves, Filipe; Rocha, Ana Maria A.C.; Pereira, Ana I.; Leitão, PauloWith the progressive increase in the complexity of dynamic environments, systems require an evolutionary configuration and optimization to meet the increased demand. In this sense, any change in the conditions of systems or products may require distributed scheduling and resource allocation of more elementary services. Centralized approaches might fall into bottleneck issues, becoming complex to adapt, especially in case of unexpected events. Thus, Multi-agent systems (MAS) can extract their automatic and autonomous behaviour to enhance the task effort distribution and support the scheduling decision-making. On the other hand, MAS is able to obtain quick solutions, through cooperation and smart control by agents, empowered by their coordination and interoperability. By leveraging an architecture that benefits of a collaboration with distributed artificial intelligence, it is proposed an approach based on a conceptual MAS design that allows distributed and intelligent management to promote technological innovation in basic concepts of society for more sustainable in everyday applications for domains with emerging needs, such as, manufacturing and healthcare scheduling systems.
- Escalonamento de visitas domiciliárias numa unidade de saúde através de algoritmos populacionaisPublication . Alves, Filipe; Pereira, Ana I.; Fernandes, Florbela P.; Fernandes, Adília; Martins, Anabela; Leitão, PauloA prestação de serviços de cuidados de saúde ao domicílio está a tornar-se uma importante área de investigação, principalmente porque, em Portugal, a população está envelhecida e é necessário providenciar serviços domiciliários apropriados e em tempo útil. As visitas domiciliárias são organizadas tendo em consideração os tratamentos médicos e o apoio geral que as pessoas idosas/doentes necessitam, as suas localizações, e claro, os recursos existentes nas Unidades de Saúde que praticam estes serviços (desde carros a enfermeiros envolvidos).
- Estudo sobre os procedimentos ótimos de visitas domiciliárias em unidades de saúdePublication . Alves, Filipe; Pereira, Ana I.; Fernandes, Florbela; Fernandes, AdíliaEm Portugal, a população está a envelhecer. Como tal, os serviços de prestação de cuidados de saúde ao domicílio estão a tornar-se numa importante área de investigação. Os cuidados domiciliários têm vindo a constituir uma resposta organizada às necessidades de tratar, cuidar e apoiar as pessoas com dependência, inseridas no seu meio, procurando promover nelas a melhor qualidade de vida possível. Este serviço de saúde pode ser prestado por equipas de enfermeiros dos Centros de Saúde. Usualmente, as visitas são planeadas de forma manual e sem apoio computacional. Neste trabalho pretende-se realizar o planeamento automático das visitas domiciliárias, de uma Unidade de Saúde de Bragança, com o objetivo de minimizar o tempo total despendido pelos enfermeiros e, consequentemente, reduzir os custos envolvidos. Para tal foram desenvolvidas e testadas várias modelações matemáticas e as mesmas foram aplicadas ao Algoritmo Genético, um método de programação global. A metodologia desenvolvida foi codificada em MatLab e permitiu resolver o problema de forma eficiente, obtendo diversas soluções de planeamento das visitas domiciliárias para os diversos dados apresentados. Em todos os horários das visitas domiciliárias a realizar pelos enfermeiros, apresentados pelo algoritmo genético, verificou-se uma redução significativa no tempo despendido dos enfermeiros, bem como, no tempo de espera dos pacientes.
- Capacitated waste collection problem solution using an open-source toolPublication . Silva, Adriano S.; Alves, Filipe; Díaz de Tuesta, Jose Luis; Rocha, Ana Maria A.C.; Pereira, Ana I.; Silva, Adrián; Gomes, HelderPopulation in cities is growing worldwide, which puts the systems that offer basic services to citizens under pressure. Among these systems, the Municipal Solid Waste Management System (MSWMS) is also affected. Waste collection and transportation is the first task in an MSWMS, carried out traditionally in most cases. This approach leads to inefficient resource and time expense since routes are prescheduled or defined upon drivers’ choices. The waste collection is recognized as an NP-hard problem that can be modeled as a Capacitated Waste Collection Problem (CWCP). Despite the good quality of works currently available in the literature, the execution time of algorithms is often forgotten, and faster algorithms are required to increase the feasibility of the solutions found. In this paper, we show the performance of the open-source Google OR-Tools to solve the CWCP in Bragança, Portugal (inland city). The three metaheuristics available in this tool were able to reduce significantly the cost associated with waste collection in less than 2 s of execution time. The result obtained in this work proves the applicability of the OR-Tools to be explored for waste collection problems considering bigger systems. Furthermore, the fast response can be useful for developing new platforms for dynamic vehicle routing problems that represent scenarios closer to the real one. We anticipate the proven efficacy of OR-Tools to solve CWCP as the starting point of developments toward applying optimization algorithms to solve real and dynamic problems.
- A human centred hybrid MAS and meta-heuristics based system for simultaneously supporting scheduling and plant layout adjustmentPublication . Alves, Filipe; Varela, Maria Leonilde R.; Rocha, Ana Maria A.C.; Pereira, Ana I.; Leitão, PauloManufacturing activities and production control are constantly growing. Despite this, it is necessary to improve the increasing variety of scheduling and layout adjustments for dynamic and flexible responses in volatile environments with disruptions or failures. Faced with the lack of realistic and practical manufacturing scenarios, this approach allows simulating and solving the problem of job shop scheduling on a production system by taking advantage of genetic algorithm and particle swarm optimization algorithm combined with the flexibility and robustness of a multi-agent system and dynamic rescheduling alternatives. Therefore, this hybrid decision support system intends to obtain optimized solutions and enable humans to interact with the system to properly adjust priorities or refine setups or solutions, in an interactive and user-friendly way. The system allows to evaluate the optimization performance of each one of the algorithms proposed, as well as to obtain decentralization in responsiveness and dynamic decisions for rescheduling due to the occurance of unexpected events.
- The sustainable home health care process based on multi-criteria decision-supportPublication . Alves, Filipe; Costa, Lino; Rocha, Ana Maria A.C.; Pereira, Ana I.; Leitão, PauloThe increase in life expectancy has led to a growing demand for Home Health Care (HHC) services. However, some problems can arise in the management of these services, leading to high computational complexity and time-consuming to obtain an exact and/or optimal solution. This study intends to contribute to an automatic multi-criteria decision-support system that allows the optimization of several objective functions simultaneously, which are often conflicting, such as costs related to travel (distance and/or time) and available resources (health professionals and vehicles) to visit the patients. In this work, the HHC scheduling and routing problem is formulated as a multi objective approach, aiming to minimize the travel distance, the travel time and the number of vehicles, taking into account specific constraints, such as the needs of patients, allocation variables, the health professionals and the transport availability. Thus, the multi-objective genetic algorithm, based on the NSGA-II, is applied to a real-world problem of HHC visits from a Health Unit in Bragança (Portugal), to identify and examine the different compromises between the objectives using a Pareto-based approach to operational planning. Moreover, this work provides several efficient end-user solutions, which were standardized and evaluated in terms of the proposed policy and compared with current practice. The outcomes demonstrate the significance of a multi-criteria approach to HHC services.
- Procedimentos ótimos para visitas domiciliárias - um caso de estudoPublication . Alves, Filipe; Pereira, Ana I.; Fernandes, Florbela P.; Fernandes, AdíliaEm Portugal, a população está a envelhecer. Como tal, os serviços de prestação de cuidados de saúde ao domicílio estão a tornar-se numa importante área de investigação. Os cuidados domiciliários têm vindo a constituir uma resposta organizada às necessidades de tratar, cuidar e apoiar as pessoas com dependência, inseridas no seu meio, procurando promover nelas a melhor qualidade de vida possível. Este serviço de saúde pode ser prestado por equipas de enfermeiros dos Centros de Saúde. Usualmente, as visitas são planeadas de forma manual e sem apoio computacional.
- Cluster analysis for breast cancer patterns identificationPublication . Azevedo, Beatriz Flamia; Alves, Filipe; Rocha, Ana Maria A.C.; Pereira, Ana I.Safety in patient decision-making is one of the major health care challenges. Computational support in establishing diagnoses and preventing errors will contribute to an enhancement in doctor-patient communication. This work performs a three-dimensional cluster analysis, using k-means algorithm, to identify patterns in a breast cancer database. The methodology proposed can be useful to identify patterns in the database that are normally difficult to be noted by classical methods, such as statistical methods. The three-dimensional cluster approach was explored combining three variables at once. The k-means algorithm is used to recognize the hidden patterns on the database. Sub-clusters are used to separate the benign and malignant tumors inside the global cluster. The results present effective analyses of three different clusters based on different combinations between variables. Thus, health professionals can obtain a better understanding of the properties of different types of tumor, identifying the mined abstract tumor features, through the cluster data analysis.
- Solving a capacitated waste collection problem using an open-source toolPublication . Silva, Adriano S.; Alves, Filipe; Díaz de Tuesta, Jose Luis; Rocha, Ana Maria A.C.; Pereira, Ana I.; Silva, Adrián; Leitão, Paulo; Gomes, HelderIncreasing complexity in municipal solid waste streams worldwide is pressing Solid Waste Management Systems (SWMS), which need solutions to manage the waste properly. Waste collection and transport is the first task, traditionally carried out by countries/municipalities responsible for waste management. In this approach, drivers are responsible for decision-making regarding collection routes, leading to inefficient resource expenses. In this sense, strategies to optimize waste collection routes are receiving increasing interest from authorities, companies and the scientific community. Works in this strand usually focus on waste collection route optimization in big cities, but small towns could also benefit from technological development to improve their SWMS. Waste collection is related to combinatorial optimization that can be modeled as the capacitated vehicle routing problem. In this paper, a Capacitated Waste Collection Problem will be considered to evaluate the performance of metaheuristic approaches in waste collection optimization in the city of Bragança, Portugal. The algorithms used are available on Google OR-tools, an open-source tool with modules for solving routing problems. The Guided Local Search obtained the best results in optimizing waste collection planning. Furthermore, a comparison with real waste collection data showed that the results obtained with the application of OR-Tools are promising to save resources in waste collection.
- Solving a logistics system for vehicle routing problem using an open-source toolPublication . Alves, Filipe; Pacheco, Filipe; Rocha, Ana Maria A.C.; Pereira, Ana I.; Leitão, PauloThe growing demand for logistics services for deliveries, collections, or home health services, have significantly increased. However, there is a need to have a technologically innovative information system for digitizing data in the operational logistics of these services, required for an increasingly better vehicle route planning. Unsurprisingly, for many years, there has been an increasing and steady growth in the interest and development of optimization tools to solve real-world problems, namely in the logistic domain. The evolution and support of computational power and the fact that advances in optimization solvers have allowed many of them to be developed as free or open-source software, to the detriment of some classic numerical calculation software. The main issue arises in the dynamic search for solutions obtained by open-source solvers and how they can be useful in solving complex combinatorial problems in real life, such as the optimal allocation of routes in logistics planning services. This work proposes an application that integrates the Google OR-Tools software and the Google Maps and Distance Matrix API. The approach developed in this work uses a VRP mathematical model to minimize the maximum route (considering as objective function the time or the distance) and provide a workload balancing, with the use of a cloud application to reduce costs and an online map service. Experimental results were obtained on simulated VRP instances in the district of Porto, where the quality of the computational solution is analyzed for training and easy usability in logistics problems.
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