Stefano Paolozzi

Ontology Extraction for Knowledge Reuse: The e-Learning Perspective

Ontologies have been frequently employed in order to solve problems derived from the management of shared distributed knowledge and the efficient integration of information across different applications. However, the process of ontology building is still a lengthy and error-prone task. Therefore, a number of research studies to (semi-)automatically build ontologies from existing documents have been developed. In this paper, we present our approach to extract relevant ontology concepts and their relationships from a knowledge base of heterogeneous text documents. We also show the architecture of the implemented system and discuss the experiments in a real-world context.

ARISTOTELE: A Semantic-Driven Platform for Enterprise Management

We present the architecture of the ARISTOTELE platform, a semantic-based collaborative system for managing enterprises and organizations, specifically designed to include a variety of features. These range from top-level functionalities like managing enterprise processes and building innovation, to finer-grained tasks like customized support for the daily activities of workers, including the creation and execution of personalized learning activities via an adaptive/non-adaptive strategy and the acquisition and usage of collaborative knowledge by the members of the organization. Here, we motivate ARISTOTELEs compliance with a known Enterprise Architecture framework and describe the design methodology behind the platform and its building blocks, beginning with its data layer and then proceeding to detailing its core services and the higher-level tools built on top of them.

SketchML a representation language for novel sketch recognition approach

Multimodal interfaces can be profitably used to support increasingly complex services in assistive environments. In particular, sketch-based interfaces offer users an effortless and powerful communication way to represent concepts and commands on different devices. Unlike other modalities, sketch-based interaction can be easily fitted according to heterogeneous services. Moreover it can be quickly personalized according to the user needs. Developing a sketch-based interface for a specific service is a time-consuming operation that requires the re-engineering and/or the re-designing of the whole recognizer framework. This paper describes a definitive framework by which the user, simply by using freehand drawing, can define every kind of sketch-based interface. The definition of the interface and its recognition process are performed by using our developed Sketch Modeling Language (SketchML).

Effective ontology management in virtual learning environments

Ontologies define a common vocabulary to share domain information. Many researches have proved the importance of ontologies as a main technology for knowledge modelling. Moreover, many authors have emphasised the use of ontologies to augment the effectiveness of the management aspects of e-learning resources. In this paper, we present a set of methodologies and techniques for the definition of a Semantic Virtual Learning Environment (SVLE) whose purpose is to provide customised and contextualised learning experiences. These experiences are achieved exploiting the implicit knowledge modelling of the reference domain through an extensive use of ontology management techniques.

Interoperability for Semantic Annotations

During the past few years, personal portable computer systems such as PDAs or laptops are being used in different contexts such as in meetings, at the office, or at home. In the current era of multimodal interaction, each context may require other interaction strategies or system settings to allow the end-users to reach their envisioned goals. For instance, in a meeting room a user may want to use the projection equipment and disable the audio output for a presentation, while audio input and output may be important while in a teleconference. In present computer systems most changes have to be made manually and require explicit interaction with the system. The number of different devices used in such environments makes that this configuration step results in a high cognitive load and causes interrupts of the tasks being executed by the end-user. In this paper we present how proactive user interfaces may predict the next interface changes invoked by context switches or user actions. In particular, we will focus on two machine learning algorithms, decision trees and Markov models, that may support this proactive behaviour for multimodal user interfaces. Based on some simple but relevant scenarios, we compare the outcome of both implementations in order to decide which algorithm is most applicable in this context.Semantic annotations represent a basic technology for the creation of meaningful content for the semantic Web. Many tools have been developed to realize semantic annotations platforms also using ontologies. An important characteristic such tools should satisfy is the semantic interoperability with other systems or tools. In this paper we examine problems of interoperability between different semantic annotations systems proposing solutions based on model management technique, with particular attention to the ModelGen operator.

A scalable and extensible framework for query answering over RDF

The Semantic Web is gaining increasing interest to fulfill the need of sharing, retrieving, and reusing information. In this context, the Resource Description Framework (RDF) has been conceived to provide an easy way to represent any kind of data and metadata, according to a lightweight model and syntaxes for serialization (RDF/XML, N3, etc.). Despite RDF has the advantage of being general and simple, it cannot be used as a storage model as it is, since it can be easily shown that even simple management operations involve serious performance limitations. In this paper we present a framework which provides a flexible and persistent layer relying on a novel storage model that guarantees good scalability and performance of query evaluation. The approach is based on the notion of construct, that represents a concept of the domain of interest. This makes the approach easily extensible and independent from the specific knowledge representation language. Based on this representation, reasoning capabilities are supported by a rule-based engine. Finally we present experimental results over real world scenarios to demonstrate the feasibility of the approach.

A Framework for Designing and Recognizing Sketch-Based Libraries for Pervasive Systems

Sketch-based interfaces enable users to effortless and powerfully communication way to represent concepts and/or commands, in different application domains, on different devices. Developing of a sketch-based interface for recognizing each specific domain is a timeconsuming operation that requires the re-engineering and/or the redesigning of the whole recognition framework.

A Novel Recognition Approach for Sketch-Based Interfaces

Multimodal interfaces can be profitably used to support the more and more complex applications and services which support human activities in everyday life. In particular, sketch-based interfaces offer users an effortless and powerful communication way to represent concepts and/or commands on different devices. Developing a sketch-based interface for a specific application or service is a time-consuming operation that requires the re-engineering and/or the re-designing of the whole recognizer framework. This paper describes a definitive framework that allows users to define each kind of sketch-based interface, using freehand drawing only. The definition of the interface and its recognition process are performed using our developed Sketch Modeling Language ( SketchML ).

Ontology-Based System for Enterprise 2.0

Enterprise 2.0 is mainly focused on answering to people needs and to stimulate flexibility, adaptability and innovation. Ontologies define a common vocabulary to share domain information and are used to state the meaning of terms used in data produced, shared and consumed within the context of Semantic Web applications. In this paper we propose a conceptual architecture where ontologies are used to support the social, open and adaptive views of Enterprise 2.0. We also show how the main elements of the architecture can be exploit in an organizational e-learning scenario.

Grid based software solutions to manage the lifecycle of collaborative learning environments

In this paper the authors present two software solutions, developed in the context of the Business Experiment in GRID project (BEinGRID), and discuss on their applicability in the creation and management of distributed collaborative learning environments. In particular, the presented solutions are deemed useful to complete the current tools for the creation and management of these environments by addressing gaping issues like trust management and ensuring quality of service. The software solutions have been validated in the context of a concrete case study related to the creation of a collaborative environment to support the execution and provision of Massive Multiplayer Online Games. As a case study, this paper will provide a description of the way the presented solutions can be applied to create collaborative learning environments, like for example the Virtual Learning Community defned in the context of the European Learning Grid Infrastructure project.