Mirko Orsini

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MOMIS (Mediator EnvirOnment for Multiple Information Sources) is an Open Source Data Integration system able to aggregate data coming from heterogeneous data sources (structured and semistructured) in a semi-automatic way. DataRiver is a Spin-Off of the University of Modena and Reggio Emilia that has re-engineered the MOMIS system, and released its Open(More)
We propose the demonstration of Keymantic, a system for keyword-based searching in relational databases that does not require a-priori knowledge of instances held in a database. It finds numerous applications in situations where traditional keyword-based searching techniques are inapplicable due to the unavailability of the database contents for the(More)
A new kind of metadata offers a synthesized view of an attribute's values for a user to exploit when creating or refining a search query in data-integration systems. The extraction technique that obtains these values is automatic and independent of an attribute domain but parameterized with various metrics for similarity measures. The authors describe a(More)
Data warehouse architectures rely on extraction, transformation and loading (ETL) processes for the creation of an updated, consistent and materialized view of a set of data sources. In this paper, we aim to support these processes by proposing a tool for the semi-automatic definition of inter-attribute semantic mappings and transformation functions. The(More)
In this paper we present RELEVANTNews, a web feed reader that automatically groups news related to the same topic published in different newspapers in different days. The tool is based on RELEVANT, a previously developed tool, which computes the “relevant values”, i.e. a subset of the values of a string attribute. Clustering the titles of the news feeds(More)
In this paper, we follow the role-based access control (RBAC) approach and extend it to provide for the dynamic association of roles with users. In our framework, privileges associated with resources are assigned depending on the attribute values of the resources, attribute values associated with users determine the association of users with privileges, and(More)
During the last decade many data integration systems characterized by a classical wrapper/mediator architecture [1] based on a Global Virtual Schema (Global Virtual View GVV) have been proposed. The data sources store data, while the GVV provides a reconciled, integrated, and virtual view of the underlying sources. Each mediator system proposed (see [2] for(More)
We investigate a security framework for collaborative applications that relies on the role-based access control (RBAC) model. In our framework, roles are pre-defined and organized in a hierarchy (partial order). However, we assume that users are not previously identified, therefore the actions that they can perform are dynamically determined based on their(More)
Research on data integration has provided a set of rich and well understood schema mediation languages and systems that provide a meta-data representation of the modeled real world, while, in general, they do not deal with data instances. Such meta-data are necessary for querying classes result of an integration process: the end user typically does not know(More)