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Publicações

Publicações por CESE

2021

A RELEVÂNCIA DO PORTAL BASE, À LUZ DOS PRINCÍPIOS FUNDAMENTAIS DA CONTRATAÇÃO PÚBLICA E DO PROCEDIMENTO DE FORMAÇÃO DOS CONTRATOS PÚBLICOS EM PORTUGAL

Autores
Anjos Azevedo, P; Rua Carneiro, D;

Publicação
Dereito: revista xurídica da Universidade de Santiago de Compostela

Abstract
Resumo Na formação e execução dos contratos públicos devem ser respeitados os princípios da legalidade, prossecução do interesse público, imparcialidade, proporcionalidade, boa-fé, tutela da confiança, sustentabilidade e responsabilidade, concorrência, publicidade e transparência, igualdade de tratamento e não-discriminação. O procedimento de formação de contratos constitui a sucessão ordenada de atos que concorrem para a formação, a conclusão e a produção de uma plena eficácia jurídica de um contrato público. O legislador define os momentos que constituem a tramitação do procedimento, numa lógica de transparência, garantindo a imparcialidade e a igualdade de tratamento e de acesso ao procedimento e a adequação procedimental. O objetivo principal do portal Base é divulgar informação sobre os contratos públicos celebrados em Portugal sujeitos ao regime do Código dos Contratos Públicos. Para dar cumprimento a este objetivo, o portal constitui-se como uma ferramenta tecnológica que centraliza, num espaço virtual, informações referentes à formação e execução dos contratos públicos. Palavras-Chave: Portal Base; princípios; contratação pública; procedimento; contratos públicos

2021

Synthetic dataset to study breaks in the consumer's water consumption patterns

Autores
Santos, MC; Borges, AI; Carneiro, DR; Ferreira, FJ;

Publicação
ICoMS 2021: 4th International Conference on Mathematics and Statistics, Paris, France, June 24 - 26, 2021

Abstract
Breaks in water consumption records can represent apparent losses which are generally associated with the volumes of water that are consumed but not billed. The detection of these losses at the appropriate time can have a significant economic impact on the water company's revenues. However, the real datasets available to test and evaluate the current methods on the detection of breaks are not always large enough or do not present abnormal water consumption patterns. This study proposes an approach to generate synthetic data of water consumption with structural breaks which follows the statistical proprieties of real datasets from a hotel and a hospital. The parameters of the best-fit probability distributions (gamma, Weibull, log-Normal, log-logistic, and exponential) to real water consumption data are used to generate the new datasets. Two decreasing breaks on the mean were inserted in each new dataset associated with one selected probability distribution for each study case with a time horizon of 914 days. Three different change point detection methods provided by the R packages strucchange and changepoint were evaluated making use of these new datasets. Based on Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) performance indices, a higher performance has been observed for the breakpoint method provided by the package strucchange.

2020

Geographically Separating Sectors in Multi-Objective Location-RoutingProblems

Autores
Teymourifar, A; Rodrigues, AM; Ferreira, JS;

Publicação
WSEAS TRANSACTIONS ON COMPUTERS

Abstract
This paper deals with multi-objective location-routing problems (MO-LRPs) and follows a sectorizationapproach, which means customers are divided into different sectors, and a distribution centre is opened for eachsector. The literature has considered objectives such as minimizing the number of opened distribution centres,the variances of compactness, distances and demands in sectors. However, the achievement of these objectivescannot guarantee the geographical separation of sectors. In this sense, and as the geographical separation ofsectors can have significant practical relevance, we propose a new objective function and solve a benchmarkof problems with the non-dominated sorting genetic algorithm (NSGA-II), which finds multiple non-dominatedsolutions. A comparison of the results shows the effectiveness of the introduced objective function, since, in thenon-dominated solutions obtained, the sectors are more geographically separated when the values of the objectivefunction improve.

2020

A Comparison between NSGA-II and NSGA-III to Solve Multi-Objective Sectorization Problems based on Statistical Parameter Tuning

Autores
Teymourifar, A; Rodrigues, AM; Ferreira, JS;

Publicação
Proceedings - 24th International Conference on Circuits, Systems, Communications and Computers, CSCC 2020

Abstract
This paper compares the non-dominated sorting genetic algorithm (NSGA-II) and NSGA-III to solve multiobjective sectorization problems (MO-SPs). We focus on the effects of the parameters of the algorithms on their performance and we use statistical experimental design to find more effective parameters. For this purpose, the analysis of variance (ANOVA), Taguchi design and response surface method (RSM) are used. The criterion of the comparison is the number of obtained nondominated solutions by the algorithms. The aim of the problem is to divide a region that contains distribution centres (DCs) and customers into smaller and balanced regions in terms of demands and distances, for which we generate benchmarks. The results show that the performance of algorithms improves with appropriate parameter definition. With the parameters defined based on the experiments, NSGA-III outperforms NSGA-II. © 2020 IEEE.

2020

Industrial business associations improving the internationalisation of SMEs with digital platforms: A design science research approach

Autores
Costa, E; Soares, AL; Sousa, JP;

Publicação
INTERNATIONAL JOURNAL OF INFORMATION MANAGEMENT

Abstract
This paper aims to contribute to the lack of design knowledge on digital platforms (DPs), by studying the new and specific context of DPs managed by industrial business associations (IBAs) to improve the inter- nationalisation of small and medium enterprises (SMEs). A specific objective is to elicit detailed digital plat- form ?s requirements and features for this particular organisational context. A design science research (DSR) approach is adopted to develop design propositions (the artifact), following the context -intervention -me- chanism -outcome logic (CIMO-logic). The design propositions are derived for DPs that can support different types of generative mechanisms of social interaction: information sharing, collaboration, and collective action. The design propositions are obtained by balancing empirical knowledge based on interviews performed with IBAs and SMEs in Portugal and in the UK, with theoretical knowledge from the literature of information systems, DPs and collaborative networks (CNs). The utility of the design propositions is further evaluated by experts and IBAs. The findings are proved to be relevant for practice, mainly for IBAs, SMEs, and digital platform designers to develop more effective collaborative DPs and sociotechnical systems, supporting CNs and the internationalisa- tion needs of SMEs. The knowledge generated in this study brings new design knowledge on DPs, contributing with design propositions translated into tangible and concrete requirements and capabilities, situated in a specific context and empirical setting.

2020

Decision-support challenges in the chemical-pharmaceutical industry: Findings and future research directions

Autores
Marques, CM; Moniz, S; de Sousa, JP; Barbosa Povoa, AP; Reklaitis, G;

Publicação
COMPUTERS & CHEMICAL ENGINEERING

Abstract
The chemical-pharmaceutical sector is facing an unprecedented fast-changing environment, with new market and technological trends impacting the companies' operational strategies. Managing the pharmaceutical supply chain (PSC) operations is, therefore, ever more complex and challenging. The goal of this work is to present a comprehensive overview of the current state of the industry and research developments; and then, to develop a new decision-making reference framework to assist in the creation of optimization-based decision support models. This will be achieved through a multi-perspective analysis that encompasses strategic and tactical planning decision-making, in the current and future business context of the chemical-pharmaceutical industry. The findings reveal a lack of research addressing the most prominent trends currently driving this sector, such as patient centricity or new technological developments, thus highlighting the disruptive nature of the expected changes in a highly conservative industry.

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