Abstract
This paper deals with the design and implementation of a data model and operations for dealing with continuously changing spatial data in object-relational DBMS. The data model relies on abstract data types but we introduce modifications to the internal structure of the spatiotemporal data representations proposed in the literature, to reduce storage requirements and to enable the reutilization of data during the execution of the queries. We show how to implement spatiotemporal operations relying on the spatial functions released by the underlying DBMS and how to use the alternative data representations to reduce the volume of temporary data created in the evaluation of spatiotemporal operations. We also discuss on the advantages and disadvantages of the proposed solutions. © 2012 ACM.

Abstract
The paper presents a proposal high-level model for the development of Educational Collaborative virtual Environments based on engineering software and quality concepts for software development. A life cycle was identified, which was detailed the phases of development, taking into account different techniques and methods and related documentation. The main goal of this research is to demonstrate how we can use the model to develop our applications by virtual world's platforms. The model was conceived based on research carried out in area the development of models that integrate all phases of process development software and models for assessing collaborative virtual environments. The model used contains a set of diagrams to support developer teams in their tasks, mainly in the creation of educational collaborative virtual environments to be used in an e-learning context. © 2012 IEEE.

Abstract

Abstract
The paper presents an proposal model for assessing the quality of educational collaborative virtual environments. This model is based on the Quantitative Evaluation framework developed by Escudeiro in 2008 and it consists in five phases. The purpose is to establish a theoretical model that highlights a number of relevant set of requirements in relation to the quality in educational collaborative virtual environments in order to facilitate the assessment of educational collaborative virtual environments. It is intended to apply the model during the lifecycle of product development and the selection of environment to support the learning/teaching process.

Abstract
With the goal of lessening barriers to the learning of advanced programming techniques, we put into place a trial which required students to get involved with online communities of programmers. Using a course assignment on software architecture styles, students had study a problem, find basis for a tentative approach, and discuss it online with programmers. The expectation was that students would find motivation for their studies from both the contact with communities of programmers, and from having to study and reflect upon their problem well enough to be able to draw the interest of members of those communities. We present the strategy we used, the developments and outcomes, and ideas for further application of this approach. © 2012 IEEE.

Abstract
This paper presents two contributions: (i) a system architecture capable of staging platform-independent choreographies within different virtual worlds, and (ii) an ontology-based solution for capturing and representing multi-user choreographies with reduced time/effort. We argue that choreographies for virtual worlds should be clearly separated from the technical characteristics of their execution in virtual world technological platforms. Due to the heterogeneity of the various virtual worlds and their domain requirements, we propose exploiting the modularity, generality, and granularity dimensions of ontologies to simplify and empower the choreography modeling capabilities. Instead of a unique ontology, several ontologies with different levels of generality and granularity can be progressively combined to support the modeling requirements of a given choreography. Because these ontologies are aligned with the ontology of each specific virtual world platform, the mapping and transformation between the core ontology is simplified and automated, thus reducing the development and time-to-market.