Abstract
In this paper we present an approach that makes possible the staging of choreographies for education and training purposes in potentially any virtual world platform. A choreography is seen here as the description of a set of actions that must or may be executed by a group of participants, including the goals to be achieved and any restrictions that may exist. We present a system-architecture and the formalization of a set of processes that are able to transform a choreography from a platform-independent representation into a specific virtual world platform's representation. We adopt an ontology-based approach with distinct levels of abstraction for capturing and representing multi-actors and multi-domain choreographies to be staged in virtual world platforms with distinct characteristics. Ontologies are characterized according to two complementary dimensions - choreography's domain (independent and dependent) and virtual world platform (independent and dependent) - giving rise to four ontologies. Ontology mappings between these ontologies enable the automatic generation of a choreography for virtually any target virtual world platform, thus reducing the time and effort of the choreography development. © 2014 Springer International Publishing.

Abstract
This paper presents an approach that enables the staging of choreographies for education and training purposes in multiple virtual world platforms. Choreography is the description of a set of actions that must or may be executed by a group of participants, including the goals to be achieved and any restrictions that may exist. For capturing and representing multi-actor multidomain choreographies an approach based on ontologies with distinct levels of abstraction is adopted. Further, this paper proposes a modelling driven approach and a set of processes that, through mappings between ontologies, enable the automatic construction of a platform-specific choreography from a platform-independent one, thus reducing the time and effort of the choreography development. For this, the MDA paradigm was adopted and adapted in a way where models can reflect two dimensions of independence: platform independence and application domain independence. We also point the guidelines for staging the choreography in a virtual world platform.

Abstract
As the amount of content and the number of users in social relationships is continually growing in the Internet, resource sharing and access policy management is difficult, time-consuming and error-prone. Cross-domain recommendation of private or protected resources managed and secured by each domain’s specific access rules is impracticable due to private security policies and poor sharing mechanisms. This work focus on exploiting resource’s content, user’s preferences, users’ social networks and semantic information to cross-relate different resources through their meta information using recommendation techniques that combine collaborative-filtering techniques with semantics annotations, by generating associations between resources. The semantic similarities established between resources are used on a hybrid recommendation engine that interprets user and resources’ semantic information. The recommendation engine allows the promotion and discovery of unknownunknown resources to users that could not even know about the existence of those resources thus providing means to solve the cross-domain recommendation of private or protected resources. © Springer International Publishing AG 2016.

Abstract
In a world overwhelmed by constant data creation and manipulation, where privacy is becoming a real concern, topics like data usage control, accountability, provenance, protected sharing of resources and trustworthiness of knowledge sources are becoming main topics of discussion among communities of interest. In this paper enhancements are proposed for an existing framework that tackles some of the afore mentioned issues namely data provenance, usage control and accountability. Such proposals consist of providing means for publishing resources in a private manner hereby making websites behave like meshes of hyperlinked resources from different domains, not only for resources publicly published but also for the ones protected by access policies. © 2014, Society, Privacy and the Semantic Web Policy and Technology.

Abstract
Analysis of automatically-generated alignments shows that ambiguous situations are quite common, preventing their application in scenarios demanding high quality and completeness, such ontology mediation (e.g. data transformation and information/knowledge integration). Even the best-performing alignment needs to be manually corrected, completed and verified before application. In this paper, we propose a decision support system (DSS) based in a general-purpose rule engine that assists the expert on improving and completing the automatically-generated alignments into fully-fledged alignments, balancing the precision and recall of the system with the user participation in the process. For that, the rules capture the preconditions (existing facts) and the actions to solve each (ambiguous) alignment scenario, in which the expert decision will be adopted in further automatic decisions. The evaluation of the proposed DSS shows the gain in reducing the need for expert's decisions while increasing the accuracy of the alignments. © 2017 Copyright is held by the owner/author(s).

Abstract
In agent mediated electronic commerce the diversity of the involved actors can lead to diff erent conceptualizations of their needs and capabilities giving rise to semantic incompatibilities that might hamper negotiations and the fulfilling of satisfactory transactions. In order to provide help in the conversation among diff erent agents, these systems should provide ontology services, more specifically, ontology matching services. However, given the natural ambiguity of the ontology matching process, raising the possibility of multiple alignments between the same pair of ontologies, it is necessary to choose the one that best meets the interests of both agents. On the other hand, agents may possess diff erent interests, therefore the ontology alignment may also become the object of further negotiation. In this context, the application and exploitation of relationships captured in social networks can result in the establishment of more accurate adequacy relations of ontology alignments to agents, as well as the improvement of the negotiations' efficiency and, consequently, the users' satisfaction with the electronic commerce system. In this paper we present the AEMOS system which follows an ontology-based information integration approach, exploiting the ontology matching paradigm, improved by the application and exploitation of the relationships captured in the social networks. Copyright © 2014, Australian Computer Society Inc.