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Publications

Publications by CESE

2020

Design of a Route-Planner for Urban Public Transport, Promoting Social Inclusion

Authors
Dias, R; Fontes, T; Galvao, T;

Publication
INTELLIGENT TRANSPORT SYSTEMS

Abstract
People that do not have access to the transport system and therefore, a facilitated access to goods and services essential to daily life, can be regarded as transport-related social excluded. This is a big issue, namely for groups of people that have physical, sensorial and/or cognitive limitations. This paper provides guidelines to design route planners for socially excluded groups, by promoting social inclusion in public transportation. For this purpose, a set of mock-up user-interfaces of an inclusive inter-modal route planning application were developed. These interfaces will deliver ready availability of information about infrastructures and other journey related data.

2020

A multi objective approach for DRT service using tabu search

Authors
Torgal, M; Dias, TG; Fontes, T;

Publication
Transportation Research Procedia

Abstract
Urban population is increasing fast. This is creating new challenges to public transport systems since some groups of citizens as elderly people may have sensory, cognitive or motor impairments that need to be addressed. This work explores the potential of a Demand Responsive Transport (DRT) system for people with reduced mobility in an urban environment. For this purpose, the Dial-A-Ride Problem (DARP) was implemented using a multivariable minimisation approach. In this approach, an Assigning Request to Vehicles (ARV) algorithm is used to obtain an initial solution. Then a Multi-Objective Tabu Search Algorithm (MOTSA) is applied to the initial solution to search for the non-dominated solution (optimisation phase). In this optimisation phase, the total travelled distance, the deadheading distance and the number of vehicles were minimised. The performance of the model was computed combining different parameters' values of the number of requests, boarding time for each user, the number of seats in each vehicle, vehicle's speed, the total number of iterations, and candidate threshold number (the algorithm's parameter). The computational results found a strong positive correlation between the number of requests and the: total travelled distance (rs = 0.977, p-value<0.001) and the number of vehicles (rs =0.883, p-value<0.001); and a low positive correlation between the number of requests and the optimised total travelled distance (rs =0.331, p-value<0.001) and the optimised number of vehicles (rs =0.340, p-value<0.001). © 2020 The Authors. Published by ELSEVIER B.V.

2020

Desafios, barreiras e aprendizagens com a remanufatura

Authors
Medeiros, FSB; Simonetto, EdO; Castro, HCGAd;

Publication
Revista de Gestão dos Países de Língua Portuguesa

Abstract
Este artigo tem como objetivo identificar os desafios, as barreiras e as aprendizagens com a atividade de remanufatura. Por meio de uma busca realizada na internet foram encontradas empresas de diferentes regiões do país que operam no setor. Desse modo, como procedimento de coleta, foi adotado o estudo de casos múltiplos e, como técnica de coleta, foi utilizada a entrevista semiestruturada, uma vez que a intenção era obter dos entrevistados o relato sobre o seu dia a dia e o seu ambiente de negócio na remanufatura. Os resultados mostraram que a atividade é carente de incentivos por parte do poder público. Outro ponto que prejudica é o custo da logística reversa. Há, ainda, a falta de locais apropriados na fase de descarte dos materiais, cujas condições de reaproveitamento no processo não são mais viáveis. Destarte, o estudo permitiu conhecer um pouco mais da remanufatura por meio do que as empresas contatadas vivenciam no mercado.

2020

Raw material depletion and scenario assessment in European Union - A circular economy approach

Authors
Martins, FF; Castro, H;

Publication
ENERGY REPORTS

Abstract
Nowadays the production systems are linear and the consumption patterns are essentially based on products with a short life cycle, which contribute to increase the demand for raw materials and environmental impacts. The Circular Economy (CE) is playing a major role among scholars and practitioners. Many aspects are now defining this new trending paradigm such as the roles of product development, transformation and remanufacturing/recycling, and/or management of waste, ensuring the economic and environmental benefits. The increasing demand causes instability of the prices and markets, and there is also the risk of supply rupture. This is very unsustainable and puts at risk countries' development. In this work we analyze and assess some EU critical raw material (CRM), considering existing global reserves and production. Correlation between several parameters was also analyzed. Under this assumption one scenario was considered to assess the depletion of two CRM. China is the main supplier in 15 out of 25 CRM considered in this analysis and its average percentage is 65%. Phosphate rock presents the highest value and antimony the lowest for depletion indicator. It was possible to conclude that no significant correlation was found between depletion, self-sufficiency and economic importance indicators. (C) 2019 Published by Elsevier Ltd.

2020

Analysing Meta-Organizations with Embedded Brokering Services Performance Modelled as a Call-Centre for Supporting Dynamic Reconfigurability of Networked and Virtual Organizations

Authors
Putnik, GD; Rodrigues, D; Alves, C; Avila, P; Castro, H; Cruz Cunha, MM;

Publication
FME TRANSACTIONS

Abstract
Various companies choose to outsource the delivery of part of their services, so as not to deviate from its core business and improve the service level. This approach leads to a new type of organizations, so-called networked and virtual enterprises, where possibly a great number of companies work together without having direct contact but through a broker, as an intermediary, that streamlines the relationships between them. To enable high level efficiency, as well as some other functional requirements, the meta-organizations and brokering services are conceived as environments and services for networked and virtual enterprises operation and dynamic reconfigurations, representing a model of organizations-of-organizations, as an implementation of one of the Industry 4.0 models and ecosystem for networked and virtual enterprises dynamic reconfiguration. In this paper, the meta-organizations with embedded brokering services, modelled as call centres, are analyzed. Various simulations are presented, based on Erlangs formulas for some of design and performance measures parameters evaluation, such as service level, average waiting time, agent occupancy and service traffic intensity.

2020

Analysis of Nonlinear Wave Parameters on Ofir Sandy Beach (NW Portugal)

Authors
Abreu, T; Silva, PA; Baptista, P; Pais Barbosa, J; Fernandez Fernandez, S; Ferreira, C; Matos, J;

Publication
ADVANCES IN NATURAL HAZARDS AND HYDROLOGICAL RISKS: MEETING THE CHALLENGE, NATHAZ' 19

Abstract
The characterization of wave transformation processes in the nearshore is of paramount importance when it comes to assessing storm and flooding impacts, sediment transportation and deposition, harbors safety or design of coastal protective structures. This study analyzes nonlinear wave parameters on Ofir sandy beach. This beach is located along the northwest Portuguese coast which is a highly energetic coast exposed to waves generated far away in the Atlantic Ocean. Despite the existence of rocky outcrops in the nearshore and intertidal zones at the study site, reducing the wave energy that reaches the beach, the study site exhibits pronounced erosive processes. Field observations of six near-bottom pressure records collected at the intertidal zone help to characterize the evolution of wave nonlinearities which are directly associated with sediment transport mechanisms. Data results show that there is an interrelation between the characteristics of the waves and the local morphology. It is also possible to ascertain, more clearly, the level of asymmetry present in the waves propagated at different depths, contributing to a better understanding of the local morpho-hydrodynamics.

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