Sergio Tasso

Generalized Bayesian inference in a fuzzy context: From theory to a virtual reality application

A generalized Bayesian inference framework in order to embed fuzzy sets and partial probabilistic information is provided. The general framework of reference is that of coherent conditional probabilities, which allows giving a rigorous interpretation of membership function as a conditional probability, regarded as a function of the conditioning event. The inferential problem needs to be studied in situations where the prior can be partial; moreover, membership and prior can be given on different classes of events. This inferential model is applied for the virtual representation of a female avatar.

Distributed and collaborative learning objects repositories on grid networks

The paper deals with the design and a prototype implementation of a collaborative repository of scientific learning objects based on an efficient mechanism of filing and retrieving distributed knowledge on the Grid. The proposed repository can deal with a large variety of different learning contents. Its prototype implementation, developed for Chemistry contents, is part of an extended architecture consisting of a federation of autonomous local repositories. The federation is led by a coordinator who keeps track of the repository in which the learning objects are directly stored or referenced. In each repository server, a locally hosted Web Portal allows a easy management of the repository through a CMS front-end.

Federation of distributed and collaborative repositories and its application on science learning objects

The paper deals with the design and the implementation of a federation of collaborative repositories for learning objects management based on an efficient mechanism of filing and retrieving distributed knowledge. The proposed federation is meant to deal with a large variety of different contents though the discussed prototype implementation is concerned with scientific and educational subjects in particular. The existing hierarchic architecture has been modified into a peer network model. Both the pure peer network and the hybrid topologies are tested to evaluate their scalability with both geographical extension and volume of contents. Additional elements of evaluation have been the capability of enhancing collaboration and fault tolerance.

Taxonomy management in a federation of distributed repositories: a chemistry use case

The increasingly popular Learning Object-based didactic approach has been investigated by considering related activities of the European Chemistry Thematic Network. Learning Objects specific interoperability and reusability properties have been considered for building a didactic-scientific repositories federation. For this reason international standards have been adopted to solve interoperability problems among the different computing elements of the adopted platforms and a module has been created to effectively manage taxonomy to classify Learning Objects via ontology-based criteria.

An efficient taxonomy assistant for a federation of science distributed repositories: a chemistry use case

The paper describes the design and the implementation of a built-in assistant software module aimed at managing the metadata of a federation of collaborative repositories of learning objects. The paper focuses mainly on the standardization of the classification criteria and their application to Molecular sciences.

Immersive molecular virtual reality based on x3d and web services

An immersive Molecular Virtual Reality environment in which the user interacts with a X3D virtual world using immersive devices and dynamic gestures is presented. The user through the virtual world invokes a Web server to perform a real-time simulation and find a stable molecular structure. The outcome of the simulation is the representation of the stable structure of the molecular system in the X3D world.

Learning Objects Efficient Handling in a Federation of Science Distributed Repositories

The dynamic sharing of learning materials among the members of a Virtual Education Community aimed at implementing a collaborative mechanism of producing, testing and improving learning objects is discussed. The resulting assemblage of an efficient distributed repositories platform offered us the opportunity of testing different search engines. The adopted solutions were found to offer an effective support to the sharing of learning objects. As a use case a Learning object dealing with the slides of lectures on the dynamics of two body collisions shared between the University of Perugia and Genoa is discussed.

A simulation framework for scheduling performance evaluation on CPU-GPU heterogeneous system

Modern PCs are equipped with multi-many core capabilities which enhance their computational power and address important issues related to the efficiency of the scheduling processes of the modern operating system in such hybrid architectures. The aim of our work is to implement a simulation framework devoted to the study of the scheduling process in hybrid systems in order to improve the system performance. Through the simulator we are able to model events and to evaluate the scheduling policy for heterogeneous systems. We implemented as a use case a simple scheduling discipline, a non-prehemptive priority queue.

Mobile Device Access to Collaborative Distributed Repositories of Chemistry Learning Objects

The educational open contents are having a very strong impact in research and training activities. In this paper we discuss the use of Internet to supply educational contents in open and free formats from distributed repositories containing educational and scientific resources. Starting from an existing federation of distributed repositories (G-Lorep) [1] and working on parameters defined by apps, we extended their functionalities to allow mobile devices access. The structure of the access, search, selection, download, use/reuse functions needed to manage learning objects on distributed repositories have also been revisited for adaptation to mobile use.

Exchange of Learning Objects Between a Learning Management System and a Federation of Science Distributed Repositories

The paper illustrates G-Lorep, a tool devoted both to dynamic sharing of learning materials among the members of a Virtual Education Community and to the implementing of a collaborative mechanism of increasing and improving learning objects. The purpose of integrating a federation of distributed repositories with an Learning Management System (LMS), allowing the sharing of information among different platforms, is to provide the capability of uploading/ downloading files on/from a common server where the LMS is installed and made available to a federated repository. As a use case the activities related to a set of chemistry learning objects generated on the LMS platform of a federated Content Management System (CMS) by the University of Genoa and used by other European Universities are considered.