Abstract. Biodiversity researchers develop predictive models for species occurrence and distribut... more Abstract. Biodiversity researchers develop predictive models for species occurrence and distribution which are useful for biodiversity conservation policies. Species distribution modelling tools need to locate and access large amount of data in different sources and produces results from different algorithms. In this scenario, collaboration is an essential feature to improve this research area. Scientists need to share models, data and results to get new discoveries. This paper presents advances in Web Biodiversity Collaborative Modelling Services (WBCMS) development. These services support sharing of modelling results and information about its generation. WBCMS also enable researcher to make new experiments based in previous one. Scientists can use WBCMS to compare experiments, to make new inferences and to improve their studies. A case study explains the model instance usage. 1.
Abstract. Investigating strategies to structure courses becomes a central question in the context... more Abstract. Investigating strategies to structure courses becomes a central question in the context of Web-based course development. This paper then proposes a collection of concepts that facilitates reuse of the material already developed, thereby reducing production cost. The proposal is based on the idea that one can profitably specialize learning objects into content objects and didactic objects. Then, a course is formalized as an aggregation of content and didactic objects with specific properties. To validate this approach, the paper also includes a comprehensive set of examples.
didactic activities for 600 computer labs of the State of Rio de Janeiro public school system. Th... more didactic activities for 600 computer labs of the State of Rio de Janeiro public school system. The project developed a set of 960 ICT-based workplans, covering 9 disciplines, from grades 5 to 12, and reaching around 60.000 students. The project started with the development of a unique educational framework that connects curriculum guidelines, contents and transversal skills. The workplans developed established links between the classroom and the computer lab: in the classroom, activities are suggested to motivate students for the upcoming computer lab work; in the lab, computer resources are used to develop skills and to help cover content; back in the classroom, teachers broaden the learning process. 2 1. Introdução
Abstract. This paper addresses the problem of formal definition of the operations on geographical... more Abstract. This paper addresses the problem of formal definition of the operations on geographical information systems (GIS). Geographical data is divided in two main classes: geo-objects and geo-fields, which represent discrete and continuous representations of reality. We study the operations over geo-fields, geo-objects, and the transformations between geo-fields and geo-objects. This analysis has been used as the basis for LEGAL, a general spatial language, which is used in the SPRING GIS, developed by INPE, with support from IBM Brasil and EMBRAPA.
This paper argues that certain ontology design problems are profitably addressed by treating onto... more This paper argues that certain ontology design problems are profitably addressed by treating ontologies as theories and by defining a set of operations that create new ontologies, including their constraints, out of other ontologies. The paper first shows how to use the operations in the context of ontology reuse, how to take advantage of the operations to compare different ontologies, or different versions of an ontology, and how the operations may help design mediated schemas in a bottom up fashion. The core of the paper discusses how to compute the operations for lightweight ontologies and addresses the question of minimizing the set of constraints of a lightweight ontology. Finally, the paper describes an implementation of the operations, as a Prot\'eg\'e plug-in.
Abstract. This paper proposes an approach to generate XML views of rela-tional data, using SQL/XM... more Abstract. This paper proposes an approach to generate XML views of rela-tional data, using SQL/XML. The paper first specify the conditions for a set of correspondence assertions to fully specify the view in terms of the relational schema and, if so, we show that the mappings defined by the view correspon-dence assertions can be expressed as SQL/XML view definition. This paper fo-cuses on an algorithm that automatically generates the SQL/XML query from the view correspondence assertions. 1.
Many complex systems, both natural and artificial, may be represented by networks of interacting ... more Many complex systems, both natural and artificial, may be represented by networks of interacting nodes. Nevertheless, it is often difficult to find meaningful correspondences between the dynamics expressed by these systems and the topological description of their networks. In contrast, many of these systems may be well described in terms of coordinated behavior of their dynamically relevant parts. In this paper we use the recently proposed Relevance Index approach, based on information-theoretic measures. Starting from the observation of the dynamical states of any system, the Relevance Index is able to provide information about its organization. Moreover, we show how the application of the proposed approach leads to novel and effective interpretations in the T helper network case study.
2015 IEEE International Conference on Computer and Information Technology; Ubiquitous Computing and Communications; Dependable, Autonomic and Secure Computing; Pervasive Intelligence and Computing, 2015
International Journal of Business Data Communications and Networking, 2011
In this paper, the authors present a three-level mediator based framework for linked data integra... more In this paper, the authors present a three-level mediator based framework for linked data integration. In the approach, the mediated schema is represented by a domain ontology, which provides a conceptual representation of the application. Each relevant data source is described by a source ontology, published on the Web according to the Linked Data principles. Each source ontology is rewritten as an application ontology, whose vocabulary is restricted to be a subset of the vocabulary of the domain ontology. The main contribution of the paper is an algorithm for reformulating a user query into sub-queries over the data sources. The reformulation algorithm exploits inter-ontology links to return more complete query results. The approach is illustrated by an example of a virtual store mediating access to online booksellers.
Abstract. Biodiversity researchers develop predictive models for species occurrence and distribut... more Abstract. Biodiversity researchers develop predictive models for species occurrence and distribution which are useful for biodiversity conservation policies. Species distribution modelling tools need to locate and access large amount of data in different sources and produces results from different algorithms. In this scenario, collaboration is an essential feature to improve this research area. Scientists need to share models, data and results to get new discoveries. This paper presents advances in Web Biodiversity Collaborative Modelling Services (WBCMS) development. These services support sharing of modelling results and information about its generation. WBCMS also enable researcher to make new experiments based in previous one. Scientists can use WBCMS to compare experiments, to make new inferences and to improve their studies. A case study explains the model instance usage. 1.
Abstract. Investigating strategies to structure courses becomes a central question in the context... more Abstract. Investigating strategies to structure courses becomes a central question in the context of Web-based course development. This paper then proposes a collection of concepts that facilitates reuse of the material already developed, thereby reducing production cost. The proposal is based on the idea that one can profitably specialize learning objects into content objects and didactic objects. Then, a course is formalized as an aggregation of content and didactic objects with specific properties. To validate this approach, the paper also includes a comprehensive set of examples.
didactic activities for 600 computer labs of the State of Rio de Janeiro public school system. Th... more didactic activities for 600 computer labs of the State of Rio de Janeiro public school system. The project developed a set of 960 ICT-based workplans, covering 9 disciplines, from grades 5 to 12, and reaching around 60.000 students. The project started with the development of a unique educational framework that connects curriculum guidelines, contents and transversal skills. The workplans developed established links between the classroom and the computer lab: in the classroom, activities are suggested to motivate students for the upcoming computer lab work; in the lab, computer resources are used to develop skills and to help cover content; back in the classroom, teachers broaden the learning process. 2 1. Introdução
Abstract. This paper addresses the problem of formal definition of the operations on geographical... more Abstract. This paper addresses the problem of formal definition of the operations on geographical information systems (GIS). Geographical data is divided in two main classes: geo-objects and geo-fields, which represent discrete and continuous representations of reality. We study the operations over geo-fields, geo-objects, and the transformations between geo-fields and geo-objects. This analysis has been used as the basis for LEGAL, a general spatial language, which is used in the SPRING GIS, developed by INPE, with support from IBM Brasil and EMBRAPA.
This paper argues that certain ontology design problems are profitably addressed by treating onto... more This paper argues that certain ontology design problems are profitably addressed by treating ontologies as theories and by defining a set of operations that create new ontologies, including their constraints, out of other ontologies. The paper first shows how to use the operations in the context of ontology reuse, how to take advantage of the operations to compare different ontologies, or different versions of an ontology, and how the operations may help design mediated schemas in a bottom up fashion. The core of the paper discusses how to compute the operations for lightweight ontologies and addresses the question of minimizing the set of constraints of a lightweight ontology. Finally, the paper describes an implementation of the operations, as a Prot\'eg\'e plug-in.
Abstract. This paper proposes an approach to generate XML views of rela-tional data, using SQL/XM... more Abstract. This paper proposes an approach to generate XML views of rela-tional data, using SQL/XML. The paper first specify the conditions for a set of correspondence assertions to fully specify the view in terms of the relational schema and, if so, we show that the mappings defined by the view correspon-dence assertions can be expressed as SQL/XML view definition. This paper fo-cuses on an algorithm that automatically generates the SQL/XML query from the view correspondence assertions. 1.
Many complex systems, both natural and artificial, may be represented by networks of interacting ... more Many complex systems, both natural and artificial, may be represented by networks of interacting nodes. Nevertheless, it is often difficult to find meaningful correspondences between the dynamics expressed by these systems and the topological description of their networks. In contrast, many of these systems may be well described in terms of coordinated behavior of their dynamically relevant parts. In this paper we use the recently proposed Relevance Index approach, based on information-theoretic measures. Starting from the observation of the dynamical states of any system, the Relevance Index is able to provide information about its organization. Moreover, we show how the application of the proposed approach leads to novel and effective interpretations in the T helper network case study.
2015 IEEE International Conference on Computer and Information Technology; Ubiquitous Computing and Communications; Dependable, Autonomic and Secure Computing; Pervasive Intelligence and Computing, 2015
International Journal of Business Data Communications and Networking, 2011
In this paper, the authors present a three-level mediator based framework for linked data integra... more In this paper, the authors present a three-level mediator based framework for linked data integration. In the approach, the mediated schema is represented by a domain ontology, which provides a conceptual representation of the application. Each relevant data source is described by a source ontology, published on the Web according to the Linked Data principles. Each source ontology is rewritten as an application ontology, whose vocabulary is restricted to be a subset of the vocabulary of the domain ontology. The main contribution of the paper is an algorithm for reformulating a user query into sub-queries over the data sources. The reformulation algorithm exploits inter-ontology links to return more complete query results. The approach is illustrated by an example of a virtual store mediating access to online booksellers.
Uploads
Papers by Marco A. Casanova