Pierluigi Del Nostro

A Semantic-Based Architecture for Managing Knowledge-Intensive Organizations: The ARISTOTELE Platform

We present the semantic-based architecture of the ARISTO-TELE platform, which is founded on the definition and development of models, methodologies, technologies and tools to support the emergence of competences and creativity within workers by self-organizing acquisition, processing and sharing of new information inside knowledge-intensi-ve organizations. ARISTOTELE’s architecture relies on semantic data by means of a number of conceptual models, which define the context of interest for an enterprise via a set of concepts and relationships among them. Instances of these models are used to annotate content data, thus creating a semantic network of information that actualizes the Linked Data paradigm within the information space of an organization. In this paper we describe the building elements of the ARISTOTELE platform, the conceptual models which lie behind them and the core Linked Data Layer component responsible of managing information for the whole system.

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.

A Novel Online Textual/Graphical Domain Separation Approach for Sketch-Based Interfaces

Multimodal interfaces can be profitably used to manage the increasingly complex applications and services which support human activities in everyday life. In particular, sketch-based interfaces enable users to effortless and powerful communication way to represent concepts and/or commands on different devices. This kind of information can be expressed by users performing two types of object: freehand drawing (graphical domain) and/or handwriting (textual domain). Usually, current frameworks require that users, somehow, indicate whether they are performing one or the other object. In this way, the frameworks can adopt the suitable recognition process to interpret as expressed by users. Moreover, more complex situations can occur when users perform, on a same schema, both types of object. This paper describes a novel intelligent framework able to automatically distinguish, in online way, freehand drawing from handwriting. The proposed approach works taking into account only the mathematical features belonging to the sketch performed by the user during interaction activity. Moreover, the approach can be used on schemata made up by heterogeneous objects which can also be overlapped.

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.

T-Araneus: Management of Temporal Data-Intensive Web Sites

T-Araneus is a tool for the generation of Web sites with special attention to temporal aspects. It is based on the use of high-level models throughout the design process, and specifically on a logical model for temporal Web sites, T-ADM, which allows the definition of page-schemes with temporal aspects.

Temporal content management and website modeling: putting them together

The adoption of high-level models for temporal, data-intensive Web sites is proposed together with a methodology for the design and development through a content management system (CMS). The process starts with a traditional ER scheme; the various steps lead to a temporal ER scheme, to a navigation scheme (called N-ER) and finally to a logical scheme (called T-ADM). The logical model allows the definition of page-schemes with temporal aspects (which could be related to the page as a whole or to individual components of it). Each model considers the temporal features that are relevant at the respective level. A content management tool associated with the methodology has been developed: from a typical content management interface it automatically generates both the relational database (with the temporal features needed) supporting the site and the actual Web pages, which can be dynamic (JSP) or static (plain HTML or XML), or a combination thereof. The tool also includes other typical features of content management all integrated with temporal features.

A Novel Approach for Practical Semantic Web Data Management

The growing importance of RDF as a tool for describing information on the Web has risen a number of interesting works regarding the management of RDF documents. The effective management of RDF data has been an increasingly pressing active area of the current research. However current data management solutions for RDF data present the following shortcomings: (i) they often define new query languages difficult to integrate in database applications, with a consequent lack of uniformity among the different approaches, (ii) they present extendibility limitations, and (iii) most of them are considered complicated by the final user. In this paper we propose a feasible and intuitive approach for practical RDF management, providing a logical organization technique for RDF data, making use of a formalism to represent concepts and properties of RDF and RDF(S), and an extension of a DataLog rule system for querying RDF documents.

Towards the Managment of Time in Data-Intensive Web Sites

The adoption of a logical model for temporal, data-intensive Web sites is proposed together with a methodology for the development. The model allows the definition of page-schemes with temporal aspects (which could be related to the page as a whole or to individual components of it). The design process follows a development that starts with a traditional E-R scheme; the various steps lead to a temporal E-R scheme, to a navigation scheme and finally to a T-ADM scheme. A tool associated with the methodology has been developed: it automatically generates both the relational database (with the temporal features needed) supporting the site and the actual Web pages, which can be dynamic (JSP) or static (plain HTML), or a combination thereof.

A Metamodel Approach to Semantic Web Data Management

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 novel approach for storing, managing and processing RDF data in an effective and efficient way. 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. We refer to real world scenarios in which we consider complex data management operations, which go beyond simple selections or projections and involve the navigation of huge portions of RDF data sources.

MIDST: Interoperability for Semantic Annotations

In the last years, interoperability of ontologies and databases has received a lot of attention. However, most of the work has concentrated on specific problems (such as storing an ontology in a database or making database data available to ontologies) and referred to specific models for each of the two. Here, we propose an approach that aims at being more general and model independent. In fact, it works for different dialects for ontologies and for various data models for databases. Also, it supports translations in both directions (ontologies to databases and vice versa) and it allows for flexibility in the translations, so that customization is possible. The proposal extends recent work for schema and data translation (the MIDST project, which implements the ModelGen operator proposed in model management), which relies on a metamodel approach, where data models and variations thereof are described in a common framework and translations are built as compositions of elementary ones.