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- 2-echelon lastmile delivery with lockers and occasional couriersPublication . Santos, André Gustavo dos; Viana, Ana; Pedroso, João PedroWe propose a new approach for the lastmile delivery problem where, besides serving as collecting points of orders for customers, parcel lockers are also used as transshipment nodes in a 2-echelon delivery system. Moreover, we consider that a customer (occasional courier) visiting a locker may accept a compensation to make a delivery to another customer on their regular traveling path. The proposed shared use of the locker facilities – by customers that prefer to self-pick up their orders, and also as a transfer deposit for customers that prefer home delivery – will contribute to better usage of an already available storage capacity. Furthermore, the use of occasional couriers (OCs) brings an extra layer of flexibility to the delivery process and may positively contribute to achieving some environmental goals: although non-consolidation of deliveries may, at first sight, seem negative, by only considering OCs that would go to the locker independently of making or not a delivery on their way home, and their selection being constrained by a maximum detour, the carbon footprint can be potentially reduced when compared to that of dedicated vehicles. We present a mixed-integer linear programming formulation for the problem that integrates three delivery options – depot to locker, depot to locker followed by final delivery by a professional fleet, and depot to locker followed by final delivery by an OC. Furthermore, to assess the impact of OCs’ no show on the delivery process, we extend the formulation to re-schedule the delivery of previous undelivered parcels, and analyze the impact of different no-show rates. Thorough computational experiments show that the use of OCs has a positive impact both on the delivery cost and on the total distance traveled by the dedicated fleets. Experiments also show that the negative impact of no-shows may be reduced by using lockers with higher capacities.
- 2017 IEEE competition on modern heuristic optimizers for smart grid operation: Testbeds and resultsPublication . Lezama, Fernando; Soares, João; Vale, Zita; Rueda, Jose; Rivera, Sergio; Elrich, IstvánThis paper summarizes the two testbeds, datasets, and results of the IEEE PES Working Group on Modern Heuristic Optimization (WGMHO) 2017 Competition on Smart Grid Operation Problems. The competition is organized with the aim of closing the gap between theory and real-world applications of evolutionary computation. Testbed 1 considers stochastic OPF (Optimal Power Flow) based Active-Reactive Power Dispatch (ARPD) under uncertainty and Testbed 2 large-scale optimal scheduling of distributed energy resources. Classical optimization methods are not able to deal with the proposed optimization problems within a reasonable time, often requiring more than one day to provide the optimal solution and a significant amount of memory to perform the computation. The proposed problems can be addressed using modern heuristic optimization approaches, enabling the achievement of good solutions in much lower execution times, adequate for the envisaged decision-making processes. Results from the competition show that metaheuristics can be successfully applied in search of efficient near-optimal solutions for the Stochastic Optimal Power Flow and large-scale energy resource management problems.
- A 2020 perspective on “Online guest profiling and hotel recommendation”Publication . Veloso, Bruno M.; Leal, Fátima; Malheiro, Benedita; Burguillo, Juan CarlosTourism crowdsourcing platforms accumulate and use large volumes of feedback data on tourism-related services to provide personalized recommendations with high impact on future tourist behavior. Typically, these recommendation engines build individual tourist profiles and suggest hotels, restaurants, attractions or routes based on the shared ratings, reviews, photos, videos or likes. Due to the dynamic nature of this scenario, where the crowd produces a continuous stream of events, we have been exploring stream-based recommendation methods, using stochastic gradient descent (SGD), to incrementally update the prediction models and post-filters to reduce the search space and improve the recommendation accuracy. In this context, we offer an update and comment on our previous article (Veloso et al., 2019a) by providing a recent literature review and identifying the challenges laying ahead concerning the online recommendation of tourism resources supported by crowdsourced data.
- A 2020 perspective on “Scalable modelling and recommendation using wiki-based crowdsourced repositories:” Fairness, scalability, and real-time recommendationPublication . Leal, Fátima; Veloso, Bruno; Malheiro, Benedita; González-Vélez, Horacio; Carlos Burguillo, JuanWiki-based crowdsourced data sources generally lack reliability, as their provenance is not intrinsically marshalled. By using recommendation, one may arguably assess the reliability of wiki-based repositories in order to identify the most interesting articles for a given domain. In this commentary, we explore current trends in scalable modelling and recommendation methods based on side information such as the quality and popularity of wiki articles. The systematic parallelization of such profiling and recommendation algorithms allows the concurrent processing of distributed crowdsourced Wikidata repositories. These algorithms, which perform incremental updating, need further research to improve the performance and generate up-to-date high-quality recommendations. This article builds upon our previous work (Leal et al., 2019) by extending the literature review and identifying important trends and challenges pertaining to crowdsourcing platforms, particularly those of Wikidata provenance.
- 2022 - O contexto atual das ITED/ITURPublication . Duarte, Jorge Manuel FerreiraNo ano de 2005, começou a obrigatoriedade de qualquer edifício ter uma infraestrutura ITED (Infraestrutura de Telecomunicações em Edifícios), quer seja na sua construção ou reconstrução. O ponto principal na elaboração do manual na sua primeira edição era de juntar a rede de pares de cobre com a rede de cabo coaxial e de fibra ótica. Por outro, dotar a nível de infraestruturas, mais concretamente a rede tubagens, para a entrada de vários operadores aos clientes, de forma que as infraestruturas não fossem o problema. Notar que, um dos objetivos principais, era que houvesse livre concorrência entre operadores e não houvesse barreiras físicas no fornecimento de serviços aos seus clientes.
- 21st century quality: Looking into the “Crystal ball”Publication . Fonseca, Luís Miguel CiravegnaThe discussion of possible scenarios for the future of Quality is on the priority list of major Quality Practitioners Societies. EOQ – European Organization for Quality (EOQ, 2014) main team for its 58th EOQ-Congress held June 2014 in Göteborg was “Managing Challenges in Quality Leadership” and ASQ - American Society for Quality (ASQ, 2015) appointed “the Future of Quality” for Quality Progress Magazine November 2015 issue. In addition, the ISO 9001:2008 revision process carried by ISO/TC 176 aims to assure that ISO 9001:2015 International Standard remains stable for the next 10 years (ISO, 2014) contributing to an increased discussion on the future of quality. The purpose of this research is to review available Quality Management approaches and outline, adding an academic perspective, expected developments for Quality within the 21st Century. This paper follows a qualitative approach, although data from international organizations is used. A literature review has been undertaken on quality management past and potential future trends. Based on these findings a model is proposed for organization quality management development and propositions for the future of quality management are advanced. Firstly, a state of the art of existing Quality Management approaches is presented, for example, like Total Quality Management (TQM) and Quality Gurus, ISO 9000 International Standards Series (with an outline of the expected changes for ISO 9001:2015), Six Sigma and Business Excellence Models.Secondly, building on theoretical and managerial approaches, a two dimensional matrix – Quality Engineering (QE - technical aspects of quality) and Quality Management (QM: soft aspects of quality) - is presented, outlining five proposed characterizations of Quality maturity levels and giving insights for applications and future developments. Literature review highlights that QM and QE may be addressing similar quality issues but their approaches are different in terms of scope breadth and intensity and they ought to complement and reciprocally reinforce one another. The challenges organizations face within the 21st century have stronger uncertainty, complexity, and differentiation. Two main propositions are advanced as relevant for 21st Century Quality: - QM importance for the sustainable success of organizations will increase and they should be aware of the larger ecosystem to be managed for improvement, possibly leading to the emergence of a new Quality paradigm, The Civilizacional Excellence paradigm. - QE should get more attention from QM and the Quality professionals will have to: a) Master and apply in wider contexts and in additional depth the Quality Tools (basic, intermediate and advanced); b) Have the soft skills needed for its success; c) Be results oriented and better understand and demonstrate the relationships between approaches and results These propositions challenge both scholars and practitioners for a sustained and supported discussion on the future of Quality. “All things are ready, if our mind be so.” (Shakespeare, Henry V, circa 1599).
- 21st Century Skills In The Teaching Of Foreign Languages At Primary And Secondary SchoolsPublication . Cruz, Mário; Orange, EditeTaking an experiential communicative approach (Fernández-Corbacho, 2014) into account, enriched by gamifi-cation strategies (Foncubierta & Rodríguez, 2015), in this paper we intend to disseminate teaching practices in English and Spanish as Foreign Languages at primary/secondary schools, which account for the development of 21st Century Skills, namely: collaboration and communication, creativity and innovation, critical thinking and problem solving. Therefore, we will present practices, developed within a Master’s Degree practical training, which illustrate the work of these skills in the classroom using: a) Web 2.0 applications in collaborative learning; b) creative and (hyper)sensory tasks which develop critical reflection; c) cross-cultural activities.
- 2D:4D digit ratio is associated with cognitive decline but not frailty in community-dwelling older adultsPublication . Gonçalves, Celina; Coelho, Tiago; Machado, Sérgio; Rocha, NunoObjectives To understand the relation between 2D:4D ratio, frailty, and cognitive decline in community-dwelling elderly people. Methods A total of 175 community-dwelling elderly people were included. To determine frailty, participants completed the Tilburg Frailty Indicator (TFI) and the Survey of Health, Ageing and Retirement in Europe (SHARE-FI). Cognitive functioning was determined using the Mini-Mental State Examination (MMSE). 2D and 4D finger lengths of each hand were measured using a scanner. Barthel Index, Lawton, and Brody scale were also completed for each participant to determine the level of daily living functioning. Results We did not find any correlations between 2D:4D ratio and frailty measures. We found a significant correlation between 2D:4D ratio and MMSE scores in the women sampled. Conclusions We cannot ascertain any contribution of prenatal exposure to androgens to the frailty status of community-dwelling elderly people. We found that reduced prenatal exposure to testosterone in women may contribute to the prevention of cognitive decline in elderly women
- 3-Nitrotyrosine quantification methods: Current concepts and future challengesPublication . Teixeira, Dulce; Fernandes, Rúben; Prudêncio, Cristina; Vieira, MónicaMeasurement of 3-nitrotyrosine (3-NT) in biological samples can be used as a biomarker of nitrosative stress, since it is very stable and suitable for analysis. Increased 3-NT levels in biological samples have been associated with several physiological and pathological conditions. Different methods have been described for the detection and quantification of this molecule, such as (i) immunological methods; (ii) liquid chromatography, namely high-pressure liquid chromatography (HPLC)-based methods that use ultraviolet-visible (UV/VIS) absorption, electrochemical (ECD) and diode array (DAD) detection, liquid chromatography-mass spectrometry (LC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS); (iii) gas chromatography, such as gas chromatography-mass spectrometry (GC-MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS). Methods A literature review on nitrosative stress, protein nitration, as well as 3-NT quantification methods was carried out. Results This review covers the different methods for analysis of 3-NT that have been developed during the last years as well as the latest advances in this field. Overall, all methods present positive and negative aspects, although it is clear that chromatography-based methods present good sensitivity and specificity. Regarding this, GC-based methods exhibit the highest sensibility in the quantification of 3-NT, although it requires a prior time consuming derivatization step. Conversely, HPLC does not require such derivatization step, despite being not as accurate as GC. Conclusion It becomes clear that all the methods described during this literature review, although accurate for 3-NT quantification, need to be improved regarding both sensitivity and specificity. Moreover, optimization of the protocols that have been described is clearly needed.
- 3C@CTDI: colaboração, contribuição e comunidade em CTDIPublication . Silva, Cândida; Oliveira, Lino; Carvalho, Milena; Martins, SusanaLos profesores de la licenciatura en Ciencias e Tecnologías da Documentaçáo e Informaçáo (CTDI) se preparan para sacar partido de las herramientas Web 2.0 como un complemento de su actividad lectiva. En este contexto, se presenta el Grupo de Investigación PlGeCo que pretende, por un lado, implementar la utilización de herramientas Web 2.0 de tal forma que se pueda conseguir ciertas premisas que actualmente orientan la nueva generación web (colaboración, contribución, comunidad), aplicando-las á la actividad lectiva e, por otro lado, el estímulo de la producción científica de los profesores y académica de los alumnos, así como su posterior análisis. Se ha hecho una valoración de los proyectos en curso y se discuten las expectativas esperadas presentado un análisis de las perspectivas y ambiciones futuras del grupo