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Publications

2020

An innovative approach for distribution network reinforcement planning: Using DER flexibility to minimize investment under uncertainty

Authors
Tavares, B; Soares, FJ;

Publication
ELECTRIC POWER SYSTEMS RESEARCH

Abstract
The increasing integration of Distributed Energy Resources (DER) in electricity networks has required an improvement in the network management procedures. While the operation paradigm is evolving and adapting to the new network features, the planning approach is rather inefficient as network assets are usually oversized to meet the worst-case scenario. In this regard, this paper presents an innovative methodology that integrates the potential flexibility of DER into the planning process, in an attempt to bridge the gap between current network operation approaches and the planning methods. It includes an analysis of future scenarios, providing different reinforcement plans considering the realistic network operation for those scenarios. The proposed optimal design of the reinforcement plans has two complementary processes: First to optimize flexible resources in their owner's perspective and second to reschedule the flexible resources' operation when the DSO needs to solve technical problems. The model has been tested in a typical Portuguese medium voltage network using future scenarios of DER integration from ENTSO-E. The results conclude that the proposed methodology leads to cost-effective solutions, which provide a better use of flexible resources, deferring high capital investments in network reinforcement.

2020

Contemporary paradigm of sustainable development in the european union

Authors
Almeida, F; Amoedo, N;

Publication
International Journal of Management and Sustainability

Abstract
This study aims to explore the level of sustainable development in the European Union and examines the relationship that may exist between the sustainability index and the population of its member states, the GDP per capita, and the investments made in R&D. Furthermore, it aims to explore the role of the geographical region as a determining factor in the performance of these countries in each sustainability dimension. The research methodology employs a quantitative approach supported by the adoption of simple and multiple linear regression, cluster analysis, and variance analysis (ANOVA). The findings reveal that R&D expenditure is mainly a determining factor in a country’s sustainable performance. Moreover, it has been possible to identify several asymmetries, with geographical region emerging as a determining factor in the performance of European Union countries in 11 of the 17 dimensions of sustainability. This work offers both theoretical and practical contributions. From the theoretical perspective, it explores the relationship between sustainability and investments in R&D, GDP per capita, and population. From a practical point of view, it offers relevant information to be used by European Union countries to establish supportive policies to enhance the sustainability of economic growth.

2020

CREATING INTERACTIVE LEARNING MATERIALS TO PROMOTE STATISTICAL SKILLS IN HIGHER EDUCATION

Authors
Lopes, AP; Soares, F; Teles, C; Rodrigues, A; Torres, C; Lopes, IC;

Publication
14TH INTERNATIONAL TECHNOLOGY, EDUCATION AND DEVELOPMENT CONFERENCE (INTED2020)

Abstract
New opportunities for lifelong learning, alternative curricula in pre-university education and fairly "open" policies on access to Higher Education (HE) have boosted, in recent decades, the problem of the lack of homogenization of knowledge and skills of "freshmen" students in Higher Education Institutions (HEI). This problem becomes overwhelming when it comes to "constructive" basic curricular units, such as Mathematics or Statistics, in non-mathematical degrees, in areas as Administration, Accounting or Management. This is a daily "struggle" faced by teachers of these curricular units as they try to talk about more advanced subjects to a very heterogeneous audience, with significant differences in Math background, promoting the participation of all students and avoiding the early drop out of some. In this sense, other didactic strategies, which include a set of activities that combine higher order thinking skills with math subjects and technology, for students of HE, appear as remedial but important, proactive and innovative measures in order to face and try to level up Math competences without risking the "repetition process", that unfortunately promotes other kind dropout behaviors. In this paper some of these strategies, developed in the Polytechnic of Porto (P.PORTO) and based on the creation and usefulness of the interactive teaching and learning materials, will be presented. The actual need for innovating in the teaching-learning process was felt and the search for a good support software, that enables to develop all the materials and implement real interactions, culminated with the choice of iSpring Suite 9. This software is a powerful eLearning toolkit for PowerPoint that allows to develop quality courses, video lectures, and assessments that will work on any desktop, laptop and mobile platform. Therefore, the use of the iSpring Suite 9 will be described, with a special focus on core objective when teaching statistics to students from the Management and Business degree in a HEI and facing the abovementioned issues - to improve students' basic statistics skills and enhance their motivation in learning Statistics.

2020

Application Ontology for Multi-Agent and Web-Services & x2019; Co-Simulation in Power and Energy Systems

Authors
Teixeira, B; Santos, G; Pinto, T; Vale, Z; Corchado, JM;

Publication
IEEE ACCESS

Abstract
Power and energy systems are very complex, and several tools are available to assist operators in their planning and operation. However, these tools do not allow a sensitive analysis of the impact of the interaction between the different sub-domains and, consequently, in obtaining more realistic and reliable results. One of the key challenges in this area is the development of decision support tools to address the problem as a whole. Tools Control Center & x2013; TOOCC & x2013; proposed and developed by the authors, enables the co-simulation of heterogeneous systems to study the electricity markets, the operation of the smart grids, and the energy management of the final consumer, among others. To this end, it uses an application ontology that supports the definition of scenarios and results comparison, while easing the interoperability among the several systems. This paper presents the application ontology developed. The paper addresses the methodology used for its development, its purpose and requirements, and its concepts, relations, facets and instances. The ontology application is illustrated through a case study, where different requirements are tested and demonstrated. It is concluded that the proposed application ontology accomplishes its goals, as it is suitable to represent the required knowledge to support the interoperability among the different considered systems.

2020

An Ontology-based approach to Knowledge-assisted Integration and Visualization of Urban Mobility Data

Authors
Sobral, T; Galvao, T; Borges, J;

Publication
EXPERT SYSTEMS WITH APPLICATIONS

Abstract
This paper proposes an ontology-based framework to support integration and visualization of data from Intelligent Transportation Systems. These activities may be technically demanding for transportation stakeholders, due to technical and human factors, and may hinder the use of visualization tools in practice. The existing ontologies do not provide the necessary semantics for integration of spatio-temporal data from such systems. Moreover, a formal representation of the components of visualization techniques and expert knowledge can leverage the development of visualization tools that facilitate data analysis. The proposed Visualization-oriented Urban Mobility Ontology (VUMO) provides a semantic foundation to knowledge-assisted visualization tools (KVTs). VUMO contains three facets that interrelate the characteristics of spatio-temporal mobility data, visualization techniques and expert knowledge. A built-in rule set leverages semantic technologies standards to infer which visualization techniques are compatible with analytical tasks, and to discover implicit relationships within integrated data. The annotation of expert knowledge encodes qualitative and quantitative feedback from domain experts that can be exploited by recommendation methods to automate part of the visualization workflow. Data from the city of Porto, Portugal were used to demonstrate practical applications of the ontology for each facet. As a foundational domain ontology, VUMO can be extended to meet the distinctiveness of a KVT.

2020

Modelling Coverage Failures Caused by Mobile Obstacles for the Selection of Faultless Visual Nodes in Wireless Sensor Networks

Authors
Jesus, TC; Costa, DG; Portugal, P; Vasques, F; Aguiar, A;

Publication
IEEE ACCESS

Abstract
Wireless sensor networks comprising nodes equipped with cameras have become common in many scenarios, providing valuable visual data for some relevant services such as localization, tracking, patterns identification and emergencies detection. In this context, algorithms and optimization approaches have been designed to perform different types of quality assessment or performance enhancement tasks, addressing challenging issues such as networking, compression, availability, reliability, security, energy efficiency and virtually any subject related to the operational challenges of those networks. However, the dynamics of coverage failures have not been properly modelled in visual sensor networks, resulting in unrealistic perceptions when optimizing or assessing quality in most visual sensing scenarios. Particularly, the Field of View of visual sensors will be affected by occlusion caused by obstacles in the monitored field, which may turn such sensors inadequate for the expected monitoring services of the considered network. Therefore, this article proposes a mathematical model to assess occlusion caused by mobile obstacles such as vehicles on a road or forklifts in an industrial plant, aiming at the selection of the visual sensor nodes that will not have their coverage significantly restricted by those obstacles. Doing so, the proposed model can be exploited by any optimization or quality assessment approach in wireless visual sensor networks, providing a preprocessing method when selecting visual nodes.

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