2017
Authors
Mendonça, FM; Soares, AL;
Publication
Ciencia da Informacao
Abstract
In the use of ontologies as knowledge information systems (KOS) for purposes of representation, organization and information retrieval, one of the biggest challenges is the ontology development process, which is complex and requires specific technical knowledge of the developers. In the recent years, several methodologies have been developed to support the ontologies building, which have steps well established, but not always well detailed for developers, causing problems in the ontologies development. This paper describes a methodology for the ontologies development, called OntoForInfoScience, which has a differential the detail of the activities of the ontology development cycle, explaining more clearly technical terms, logical and philosophical issues involved in the construction of ontologies. As current practical results of OntoForInfoScience, we presented part of the content of two ontologies developed with such methodology: (i) Hemonto: a biomedical ontology on the human blood components used for hematology and hemotherapy; (ii) Ontolegis: a legal domain ontology that represents the knowledge related to Brazilian legislative information on medical law. It is concluded that the OntoForInfoScience was very useful for the construction of formal ontological representations in both domains modeled and their details allowed to help the developers in logical and philosophical questions of the process of development and in the understanding of technical concepts of ontologies.
2017
Authors
Santos, G; Pinto, T; Praca, I; Vale, Z;
Publication
PROGRESS IN ARTIFICIAL INTELLIGENCE (EPIA 2017)
Abstract
This paper proposes the use of ontologies to enable information and knowledge exchange, to test different electricity market models and to allow players from different systems to interact in common market environments. Multi-agent based software is particularly well fitted to analyse dynamic and adaptive systems with complex interactions among its constituents, such as the complex and dynamic electricity markets. The main drivers are the markets' restructuring and evolution into regional and continental scales, along with the constant changes brought by the increasing necessity for an adequate integration of renewable energy sources. An ontology to represent the concepts related to the Nord Pool Elspot market is proposed. It is validated through a case study considering the simulation of Elspot market. Results show that heterogeneous agents are able to effectively participate in the simulation by using the proposed ontologies to support their communications with the Nord Pool market operator.
2017
Authors
Monteiro, A; Menezes, R; Silva, ME;
Publication
SPATIAL STATISTICS
Abstract
This study aims at characterizing the spatial and temporal dynamics of spatio-temporal data sets, characterized by high resolution in the temporal dimension which are becoming the norm rather than the exception in many application areas, namely environmental modelling. In particular, air pollution data, such as NO2 concentration levels, often incorporate also multiple recurring patterns in time imposed by social habits, anthropogenic activities and meteorological conditions. A two-stage modelling approach is proposed which combined with a block bootstrap procedure correctly assesses uncertainty in parameters estimates and produces reliable confidence regions for the space-time phenomenon under study. The methodology provides a model that is satisfactory in terms of goodness of fit, interpretability, parsimony, prediction and forecasting capability and computational costs. The proposed framework is potentially useful for scenario drawing in many areas, including assessment of environmental impact and environmental policies, and in a myriad applications to other research fields.
2017
Authors
Shoker, A; Yactine, H; Baquero, C;
Publication
PROCEEDINGS OF THE 3RD INTERNATIONAL WORKSHOP ON PRINCIPLES AND PRACTICE OF CONSISTENCY FOR DISTRIBUTED DATA (PAPOC 17)
Abstract
Eventual consistency (EC) is a relaxed data consistency model that, driven by the CAP theorem, trades prompt consistency for high availability. Although, this model has shown to be promising and greatly adopted by industry, the state of the art only assumes that replicas can crash and recover. However, a Byzantine replica (i.e., arbitrary or malicious) can hamper the eventual convergence of replicas to a global consistent state, thus compromising the entire service. Classical BFT state machine replication protocols cannot solve this problem due to the blocking nature of consensus, something at odd with the availability via replica divergence in the EC model. In this work in progress paper, we introduce a new secure highly available protocol for the EC model that assumes a fraction of replicas and any client can be Byzantine. To respect the essence of EC, the protocol gives priority to high availability, and thus Byzantine detection is performed off the critical path on a consistent data offset. The paper concisely explains the protocol and discusses its feasibility. We aim at presenting a more comprehensive and empirical study in the future.
2017
Authors
Heyman, F; Pereira, C; Miranda, V; Soares, FJ;
Publication
2017 IEEE PES INNOVATIVE SMART GRID TECHNOLOGIES CONFERENCE EUROPE (ISGT-EUROPE)
Abstract
The uptake of electric vehicles (EV) will require important modifications in traditional grid planning and load forecasting techniques. Existing literature suggests that the integration of EVs will be more adversarial to elements of the existing electricity infrastructure in terms of power supply (kW) than energy (kWh) delivery. While several studies analyzed the grid impact of electric vehicle fleets, few consider the adoption process itself which may lead to strong spatial variations of the utilization of charging infrastructure. The presented approach extends spatial load forecasting, introducing diffusion theory elements to analyze spatio-temporal clustering of EV charging demand. Using open-access census and grid data, this work develops a deterministic framework to forecast spatial patterns of EV charging applied to a real-world environment. Outcomes suggest substantial spatial clustering of EV adoption patterns, showing substation overrating for EV penetration rates of 25% and above with 7.4kW charging power.
2017
Authors
Veiga, L; El Baz, D; Cardoso, JMP;
Publication
JOURNAL OF COMPUTATIONAL SCIENCE
Abstract
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