ABSTRACT The regression-by-discretization approach allows the use of classification algorithm in ... more ABSTRACT The regression-by-discretization approach allows the use of classification algorithm in a regression task. It works as a pre-processing step in which the numeric target value is discretized into a set of intervals. We had applied this approach to the Hidden Markov Model for Regression (HMMR) which was successfully compared to the Naive Bayes for Regression and two traditional forecasting methods, Box-Jenkins and Winters. In this work, to further improve these results, we apply three discretization methods to HMMR using ten time series data sets. The experimental results showed that one of the discretization methods improved the results in most of the data sets, although each method improved the results in at least one data set. Therefore, it would be better to have a search algorithm to automatically find the optimal number and width of the intervals.
Revista Eletrônica de Sistemas de Informação, 2015
O trabalho apresenta uma abordagem para análise de uma comunidade científica a partir de suas pub... more O trabalho apresenta uma abordagem para análise de uma comunidade científica a partir de suas publicações. O objetivo é traçar o perfil da comunidade ao gerar indicadores obtidos a partir da mineração dos textos das publicações científicas. Os indicadores são gerados de forma automática, sendo: redes de colaboração e o contexto (classificação) dessas publicações. Um sistema foi desenvolvido para auxílio da análise, sendo dividido em dois módulos principais: geração de grafos e classificação automática de texto. Realizou-se um estudo de caso com a comunidade brasileira de pesquisa em Sistemas de Informação.
ABSTRACT A business process is a set of activities performed in a coordinated manner within an or... more ABSTRACT A business process is a set of activities performed in a coordinated manner within an organizational and technical environment that is aimed toward a business goal. The flexibility of a process is related to an understanding of the unexpected events that occur when people, systems and resources interact and require adjustments. Thus, business processes must be designed to respond to information about different events and their specificity. This information defines what the literature calls “context”. To broaden the perception of context in the case of a business process, this work proposes an approach to characterize the context of a business process activity in a given domain through conceptual models structured in layers. A case study was conducted to evaluate the proposal, which provided evidence of the applicability of the model.
ABSTRACT Dynamic adaptation is the customization of a business process to make it applicable to a... more ABSTRACT Dynamic adaptation is the customization of a business process to make it applicable to a particular situation at any time of its life cycle. Adapting requires experience, and involves knowledge about various, internal and external, aspects of business. Thus, we argue for the application of adaptation rules, considering the context of a particular process instance. Furthermore, we state that a context-based adaptation environment should go beyond, and learn from decisions, as well as continuously identify new unforeseen situations (context definitions). The aim of this paper is to present a computational engine that infers the need to update situations and adaptation rules, suggesting changes to them. An application scenario is presented to discuss the usage of the proposal.
Currently computer is essential to the success in conducting scientific research. In this context... more Currently computer is essential to the success in conducting scientific research. In this context, e-Science appears as science performed with computer support aiming efficiency. The challenge, "Computational Modeling of artificial, naturals and socio-cultural complex systems and mannature interaction" from SBC Great Challenges is strongly related to the e-Science context. The goal of this challenge is to create, evaluate, modify, compose, manage and exploit computer models in fields related to complex, artificial, natural, socio-cultural and human-nature systems. Technologies like semantic web service composition, data provenance, peer to peer networks and scientific software product line can be used as the basis for the specification and development of an e-Science infrastructure to handle challenges and solve problems. This paper discusses the main challenges involved in developing an e-Science infrastructure, presenting research goals for the next years.
Ano de Ingresso no Programa de Mestrado: 2011 Época esperada de conclusão: 04/2013 Etapas já conc... more Ano de Ingresso no Programa de Mestrado: 2011 Época esperada de conclusão: 04/2013 Etapas já concluídas: Defesa da proposta Resumo. Ontologias descrevem um domínio de conhecimento em termos de seus conceitos e relacionamentos e são essenciais para resolver problemas de heterogeneidade semântica. No entanto, a popularidade do uso de Ontologias tem favorecido o surgimento de várias Ontologias para um mesmo domínio, trazendo a necessidade de técnicas de alinhamento. Em cenários em que as Ontologias possuem instâncias, o conhecimento embutido nestas instâncias pode ser útil para melhorar este alinhamento. Por outro lado, Mineração de Dados é utilizada para extração automática de conhecimento em grande volume de dados. Desta forma, este trabalho propõe a aplicação de técnicas de Mineração de Dados para aprimorar o alinhamento. Palavras-chave: Ontologias, Mineração de Dados, Aprendizado de Máquina.
ABSTRACT This paper presents the ontology-related research themes being conducted at NP2Tec/UNIRI... more ABSTRACT This paper presents the ontology-related research themes being conducted at NP2Tec/UNIRIO. The main focuses that are being investigated handle the ontological representation of Enterprise artifacts, including structural conceptual models, process models, and business rules. Besides, maintaining a consistent representation of a Universe of Discourse is also a challenge since new (valid) facts are constantly being observed, and may not be consistent with the existing ontological representation.
Concept Maps are the main tool of the constructivist theory of Meaningful Learning and as well as... more Concept Maps are the main tool of the constructivist theory of Meaningful Learning and as well as domain ontologies, enable clarification of concepts and relationships of a domain. This article presents a model of learning assessment supported by the use of concept maps for clarification of the organization of concepts in the student's cognitive structure and alignment of ontologies in the automatic comparison of these maps with a reference ontology. An example illustrating this application is presented and discussed in this article.
ABSTRACT The regression-by-discretization approach allows the use of classification algorithm in ... more ABSTRACT The regression-by-discretization approach allows the use of classification algorithm in a regression task. It works as a pre-processing step in which the numeric target value is discretized into a set of intervals. We had applied this approach to the Hidden Markov Model for Regression (HMMR) which was successfully compared to the Naive Bayes for Regression and two traditional forecasting methods, Box-Jenkins and Winters. In this work, to further improve these results, we apply three discretization methods to HMMR using ten time series data sets. The experimental results showed that one of the discretization methods improved the results in most of the data sets, although each method improved the results in at least one data set. Therefore, it would be better to have a search algorithm to automatically find the optimal number and width of the intervals.
Revista Eletrônica de Sistemas de Informação, 2015
O trabalho apresenta uma abordagem para análise de uma comunidade científica a partir de suas pub... more O trabalho apresenta uma abordagem para análise de uma comunidade científica a partir de suas publicações. O objetivo é traçar o perfil da comunidade ao gerar indicadores obtidos a partir da mineração dos textos das publicações científicas. Os indicadores são gerados de forma automática, sendo: redes de colaboração e o contexto (classificação) dessas publicações. Um sistema foi desenvolvido para auxílio da análise, sendo dividido em dois módulos principais: geração de grafos e classificação automática de texto. Realizou-se um estudo de caso com a comunidade brasileira de pesquisa em Sistemas de Informação.
ABSTRACT A business process is a set of activities performed in a coordinated manner within an or... more ABSTRACT A business process is a set of activities performed in a coordinated manner within an organizational and technical environment that is aimed toward a business goal. The flexibility of a process is related to an understanding of the unexpected events that occur when people, systems and resources interact and require adjustments. Thus, business processes must be designed to respond to information about different events and their specificity. This information defines what the literature calls “context”. To broaden the perception of context in the case of a business process, this work proposes an approach to characterize the context of a business process activity in a given domain through conceptual models structured in layers. A case study was conducted to evaluate the proposal, which provided evidence of the applicability of the model.
ABSTRACT Dynamic adaptation is the customization of a business process to make it applicable to a... more ABSTRACT Dynamic adaptation is the customization of a business process to make it applicable to a particular situation at any time of its life cycle. Adapting requires experience, and involves knowledge about various, internal and external, aspects of business. Thus, we argue for the application of adaptation rules, considering the context of a particular process instance. Furthermore, we state that a context-based adaptation environment should go beyond, and learn from decisions, as well as continuously identify new unforeseen situations (context definitions). The aim of this paper is to present a computational engine that infers the need to update situations and adaptation rules, suggesting changes to them. An application scenario is presented to discuss the usage of the proposal.
Currently computer is essential to the success in conducting scientific research. In this context... more Currently computer is essential to the success in conducting scientific research. In this context, e-Science appears as science performed with computer support aiming efficiency. The challenge, "Computational Modeling of artificial, naturals and socio-cultural complex systems and mannature interaction" from SBC Great Challenges is strongly related to the e-Science context. The goal of this challenge is to create, evaluate, modify, compose, manage and exploit computer models in fields related to complex, artificial, natural, socio-cultural and human-nature systems. Technologies like semantic web service composition, data provenance, peer to peer networks and scientific software product line can be used as the basis for the specification and development of an e-Science infrastructure to handle challenges and solve problems. This paper discusses the main challenges involved in developing an e-Science infrastructure, presenting research goals for the next years.
Ano de Ingresso no Programa de Mestrado: 2011 Época esperada de conclusão: 04/2013 Etapas já conc... more Ano de Ingresso no Programa de Mestrado: 2011 Época esperada de conclusão: 04/2013 Etapas já concluídas: Defesa da proposta Resumo. Ontologias descrevem um domínio de conhecimento em termos de seus conceitos e relacionamentos e são essenciais para resolver problemas de heterogeneidade semântica. No entanto, a popularidade do uso de Ontologias tem favorecido o surgimento de várias Ontologias para um mesmo domínio, trazendo a necessidade de técnicas de alinhamento. Em cenários em que as Ontologias possuem instâncias, o conhecimento embutido nestas instâncias pode ser útil para melhorar este alinhamento. Por outro lado, Mineração de Dados é utilizada para extração automática de conhecimento em grande volume de dados. Desta forma, este trabalho propõe a aplicação de técnicas de Mineração de Dados para aprimorar o alinhamento. Palavras-chave: Ontologias, Mineração de Dados, Aprendizado de Máquina.
ABSTRACT This paper presents the ontology-related research themes being conducted at NP2Tec/UNIRI... more ABSTRACT This paper presents the ontology-related research themes being conducted at NP2Tec/UNIRIO. The main focuses that are being investigated handle the ontological representation of Enterprise artifacts, including structural conceptual models, process models, and business rules. Besides, maintaining a consistent representation of a Universe of Discourse is also a challenge since new (valid) facts are constantly being observed, and may not be consistent with the existing ontological representation.
Concept Maps are the main tool of the constructivist theory of Meaningful Learning and as well as... more Concept Maps are the main tool of the constructivist theory of Meaningful Learning and as well as domain ontologies, enable clarification of concepts and relationships of a domain. This article presents a model of learning assessment supported by the use of concept maps for clarification of the organization of concepts in the student's cognitive structure and alignment of ontologies in the automatic comparison of these maps with a reference ontology. An example illustrating this application is presented and discussed in this article.
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