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- O Ensino de estatística a um estudante com deficiência visual permanente bilateral (cegueira) no Ensino SuperiorPublication . Oliveira, Cristina; Rodrigues, Ana Maria; Ribeiro, Sandra; Bigotte Chorão, GraçaO Ensino de estatística a um estudante com deficiência visual permanente bilateral (cegueira) no Ensino Superior
- Electromagnetism based approach to Sector design in Waste CollectionPublication . Rodrigues, Ana Maria; Soeiro Ferreira, JoséFor efficient planning of waste collection routing, large municipalities may be partitioned into convenient sectors. The real case under consideration is the municipality of Monção, in Portugal. Waste collection involves more than 1600 containers over an area of 220 km2 and a population of around 20,000 inhabitants. This is mostly a rural area where the population is distributed in small villages around the 33 boroughs centres (freguesia) that constitute the municipality. In most freguesias, waste collection is usually conducted 3 times a week. However, there are situations in which the same collection is done every day. The case reveals some general and specific characteristics which are not rare, but are not widely addressed in the literature. Furthermore, new methods and models to deal with sectorization and routing are introduced, which can be extended to other applications. Sectorization and routing are tackled following a three-phase approach. The first phase, which is the main concern of the presentation, introduces a new method for sectorization inspired by Electromagnetism and Coulomb’s Law. The matter is not only about territorial division, but also the frequency of waste collection, which is a critical issue in these types of applications. Special characteristics related to the number and type of deposition points were also a motivation for this work. The second phase addresses the routing problems in each sector: new Mixed Capacitated Arc Routing with Limited Multi-Landfills models will be presented. The last phase integrates Sectoring and Routing. Computational results confirm the effectiveness of the entire novel approach.
- Waste collection routing-limited multiple landfills and heterogeneous fleetPublication . Rodrigues, Ana Maria; Soeiro Ferreira, JoséThis article deals with a real-life waste collection routing problem. To efficiently plan waste collection, large municipalities may be partitioned into convenient sectors and only then can routing problems be solved in each sector. Three diverse situations are described, resulting in three different new models. In the first situation, there is a single point of waste disposal from where the vehicles depart and to where they return. The vehicle fleet comprises three types of collection vehicles. In the second, the garage does not match any of the points of disposal. The vehicle is unique and the points of disposal (landfills or transfer stations) may have limitations in terms of the number of visits per day. In the third situation, disposal points are multiple (they do not coincide with the garage), they are limited in the number of visits, and the fleet is composed of two types of vehicles. Computational results based not only on instances adapted from the literature but also on real cases are presented and analyzed. In particular, the results also show the effectiveness of combining sectorization and routing to solve waste collection problems.
- Sectorization of a Parcel Delivery ServicePublication . Mostardinha, Mafalda; Escobar Hernández, Pablo; Lopes, Isabel Cristina; Rodrigues, Ana MariaThis paper explores the problem of sectorization of a parcel delivery service that wants to assign an action region to each of its teams, regarding the number of deliveries scheduled for each zone, so that there is a balanced service amongst sectors, covering contiguous zones, and considering limited capacities for the teams. Besides being relatively easy to model, the available optimization tools and software provide poor results when dimension increases in these types of problems, with computational capacity exceeding. In this paper an integer programming model, combined with an heuristic to return a faster solution, was implemented to solve a sectorization problem in two different situations. The main advantage of the strategy proposed, compared to previous ones, is its simplicity and easy implementation while still returning an optimal solution.
- An Application of Preference-Inspired Co-Evolutionary Algorithm to SectorizationPublication . Ozturk, E. Goksu; Rocha, Pedro; Sousa, Filipe; Lima, Maria Margarida; Rodrigues, Ana Maria; Soeiro Ferreira, José; Catarina Nunes, Ana; Lopes, Isabel Cristina; Oliveira, CristinaSectorization problems have significant challenges arising from the many objectives that must be optimised simultaneously. Several methods exist to deal with these many-objective optimisation problems, but each has its limitations. This paper analyses an application of Preference Inspired Co-Evolutionary Algorithms, with goal vectors (PICEA-g) to sectorization problems. The method is tested on instances of different size difficulty levels and various configurations for mutation rate and population number. The main purpose is to find the best configuration for PICEA-g to solve sectorization problems. Performancemetrics are used to evaluate these configurations regarding the solutions’ spread, convergence, and diversity in the solution space. Several test trials showed that big and medium-sized instances perform better with low mutation rates and large population sizes. The opposite is valid for the small size instances.
- Recolha de resíduos sólidos urbanos - otimização de rotasPublication . Rodrigues, Ana Maria; Soeiro Ferreira, JoséEste trabalho dá a conhecer um novo problema, Problema Capacitado de Rotas em Arcos Misto, com Múltiplos Aterros Limitados. Baseado na situação de recolha/transporte de Resíduos Sólidos Urbanos no concelho de Monção, são apresentadas características que, não sendo únicas em Portugal, nunca foram mencionadas na literatura. Diferencia-se pela existência de diversos pontos de deposição que, especialmente devido às reduzidas dimensões, apresentam restrições relacionadas com o número de visitas recebidas por dia. Um novo modelo de otimização, baseado na formulação do Mixed Ca- pacitated Arc Routing Problem é apresentado. São incluídos resultados computacionais provenientes de instâncias adaptadas da literatura e do problema real descrito.
- A resectorization of fire brigades in the north of PortugalPublication . Lima, Maria Margarida; Ozturk, E. Goksu; Sousa, FIlipe; Lopes, Isabel Cristina; Teles Oliveira, Cristina; Rodrigues, Ana Maria; Catarina Nunes, Ana; Soeiro Ferreira, JoséSectorization can be regarded as a division of a territory into smaller regions to deal with a complex problem involving multiple-criteria. Resectorization intends to achieve another sectorization, according to some new conditions but avoiding substantial changes. An example of this can be the distribution of geographical areas by fire brigades. In Portugal, fire brigades must protect and rescue the population in the areas surrounding their fire stations. So we will use the current sectorization, the geographic and population characteristics of the areas and the fire brigades’ response capacity to provide an optimised resectorization, in order to decrease rescue time. To achieve that, we will use a decision support system using different optimisation methods, such as Non-dominated Sorting Genetic Algorithm (NSGA II), which provides an effective sectorization concerning compactness and equilibrium criteria.
- Sectorization for managing maintenance techniciansPublication . Lopes, Isabel Cristina; Rodrigues, Ana Maria; Oliveira, Cristina; Soeiro Ferreira, José; Cortinhal, Maria Joãobetter organization of the region, or to simplify a large problem into smaller sub-problems, or to obtain groups with similar characteristics. To evaluate the quality of the solutions, three criteria are commonly used: Equilibrium (the sectors should be identical portions of the whole), Compactness (regular forms like circles are preferred, avoiding sectors shaped with ‘tentacles’), and Contiguity (avoid sectors divided into portions). Depending on the application, other criteria can also be considered, therefore multicriteria approaches should be used. Sectorization problems can arise when designing political districts, defining sales territories, managing routes for distribution of goods or collecting municipal waste, assigning neighborhoods to schools, locating health care services, police stations, or fire brigades. This talk will address the sectorization in an elevator maintenance company, where the definition of the zones assigned to each technician have an impact on the company’s efficiency and quality of service. In order to define the best sectorization, not only the maintenance plan should be considered, but also the unplanned interventions. We will discuss the different solution methods that can be applied to this case.
- Creating interactive learning materials to promote statistical skills in higher educationPublication . Paula Lopes, Ana; Baptista Soares, Filomena; Teles Oliveira, Cristina; Rodrigues, Ana Maria; Torres, Cristina; Lopes, CristinaNovas oportunidades de aprendizagem ao longo da vida, currículos alternativos no ensino pré-universitário e políticas bastante “abertas” de acesso ao Ensino Superior (ES) têm potenciado, nas últimas décadas, o problema da falta de homogeneização de saberes e competências dos alunos “calouros” em Instituições de Ensino Superior (IES). Este problema torna-se avassalador quando se trata de unidades curriculares básicas "construtivas", como a Matemática ou a Estatística, em licenciaturas não matemáticas, em áreas como a Administração, Contabilidade ou Gestão. Esta é uma “luta” diária que os docentes destas unidades curriculares enfrentam ao tentarem falar de disciplinas mais avançadas a um público muito heterogéneo, com diferenças significativas na formação matemática, promovendo a participação de todos os alunos e evitando o abandono precoce de alguns . Neste sentido, Neste artigo serão apresentadas algumas dessas estratégias, desenvolvidas no Politécnico do Porto (P.PORTO) e baseadas na criação e utilidade dos materiais interativos de ensino e aprendizagem. Sentiu-se a real necessidade de inovar no processo de ensino-aprendizagem e a procura de um bom software de apoio, que permitisse desenvolver todos os materiais e implementar interações reais, culminou com a escolha do iSpring Suite 9. Este software é um poderoso kit de ferramentas de eLearning para PowerPoint que permite desenvolver cursos, videoaulas e avaliações de qualidade que funcionarão em qualquer desktop, laptop e plataforma móvel. Portanto, o uso do iSpring Suite 9 será descrito...
- Cutting path as a rural postman problemPublication . Rodrigues, Ana Maria; Soeiro Ferreira, JoséThe Rural Postman Problem (RPP) is a particular Arc Routing Problem (ARP) which consists of determining a minimum cost circuit on a graph so that a given subset of required edges is traversed. The RPP is an NP-hard problem with significant real-life applications. This paper introduces an original approach based on Memetic Algorithms - the MARP algorithm - to solve the RPP and, also deals with an interesting Industrial Application, which focuses on the path optimization for component cutting operations. Memetic Algorithms are a class of Metaheuristics which may be seen as a population strategy that involves cooperation and competition processes between population elements and integrates “social knowledge”, using a local search procedure. The MARP algorithm is tested with different groups of instances and the results are compared with those gathered from other publications. MARP is also used in the context of various real-life applications.