1,721,114 research outputs found
Proceedings of SEBD 2010 - 18th Italian Symposium on Advanced Database Systems
No full textThis volume collects the papers selected for presentation at the Eighteenth
Italian Symposium on Advanced Database Systems (SEBD 2010), held in Rimini, Italy, from the 20th to the 23rd of June 2010.
SEBD is the major annual event of the Italian database research community.
The symposium is conceived as a gathering forum for the discussion and exchange of ideas and experiences among researchers and experts from the academy and industry, about all aspects of database systems and their applications.
SEBD is back in Rimini after sixteen years,
and it is interesting to observe how the landscape
of the Italian database research community has changed.
In 1994 twenty-one paper were accepted, now the
number has more than doubled, meaning that the
community has been steadily growing. Most of the topics
considered in 1994 are still around, even if the language,
the formalisms and the reference applications have changed.
The web was e-mail, ftp, Usenet, a small amount of HTML pages here
and there, and little more, now it is the
pervasive engine of information dissemination and search.
The web is so powerful to give rise to a series of brand
new ideas and applications, due to a mix of possibility and necessity.
Social systems across the web, mobility, heterogeneity
were not conceivable in the early 1990s.
Semantic web, data mining and warehousing,
streaming techniques, large scale integration
are necessary to deal with the growing amount
of data and information.
The SEBD 2010 program reflects the current interests of the Italian database researchers and covers most of the topics considered by the international research community.
Sixty papers were submitted to SEBD 2010, of which thirty-four were extended abstracts, twenty-two were research papers, and two were software demonstrations. Fifty-one papers were accepted for presentation, of which thirty-two were extended abstracts, seventeen were full research papers, and two were software demonstrations.
Besides paper presentations, the program includes two invited talks, the first by Hector Garcia-Molina (Stanford University, CA) and the second by Amr El Abbadi (University of California, CA), and a tutorial by Divesh Srivastava (AT&T Labs-Research).
We would like to thank all the authors who submitted papers and all symposium participants. We are grateful to the members of the Program Committee and the external referees for their thorough work in reviewing submissions with expertise and patience, and to the members of the SEBD Steering Committee for their support in the organization of SEBD 2010. Special thanks are due to the members of the Organizing Committee and to Polo di Rimini of the University of Bologna which made this event possible. Finally, we gratefully thank all the cooperating institutions
Keymantic: A Keyword-based Search Engine using Structural Knowledge
No full textTraditional techniques for query formulation need the knowledge of the database contents, i.e. which data are
stored in the data source and how they are represented.
In this paper, we discuss the development of a keyword-based search engine for structured data sources. The
idea is to couple the ease of use and flexibility of keyword-based search to the large amount of knowledge
derived from data structures, to help the user with metadata extracted from extensional data and to translate
keywords into SQL statements, in order to exploit the power of traditional DBMS engines. Our solution
should be effective, semantic-based, and applicable also when instance are not continuously available, such as
in integrated data sources or in data sources extracted from the deep web
European Research and Development of Intelligent Information Agents: The AgentLink Perspective
No full textThe vast amount of heterogeneous information sources available in the Internet demands advanced solutions for acquiring, mediating, and maintaining relevant information for the common user. The impacts of data, system, and semantic heterogeneity on the information overload of the user are manifold and especially due to potentially significant differences in data modeling, data structures, content representations using ontologies and vocabularies, query languages and operations to retrieve, extract, and analyse information in the appropriate context. The impacts of the increasing globalisation on the information overload encompass the tedious tasks of the user to determine and keep track of relevant information sources, to efficiently deal with different levels of abstractions of information modeling at sources, and to combine partially relevant information from potentially billions of sources. A special type of intelligent software agents , so called information agents, is supposed to cope with these difficulties associated with the information overload of the user. This implies its ability to semantically broker information by providing pro-active resource discovery, resolving the information impedance of information consumers and providers in the Internet, and offering value-added information services and products to the user or other agents. In subsequent sections we briefly introduce the reader to the notion of such type of agents as well as one of the prominent European forums for research on and development of these agents, the AgentLink special interest group on intelligent information agents. This book includes presentations of advanced systems of information agents and solution approaches to different problems in the domain that have been developed jointly by members of this special interest group in respective working groups
Objective versus Subjective Coordination in the Engineering of Agent Systems
No full textThe governance of interaction is a critical issue in the engineering of agent systems. Research on coordination addresses this issue by providing a wide range of models, abstractions and technologies. It is often the case, however, that such a wide range of proposals could not easily find an unitary and coherent conceptual framework where all the different views and solutions can be understood and compared - and this is particularly true in the context of agent models and systems. In this paper: we first discuss how all the many diverse approaches to agent coordination can be categorised in two main classes - the subjective and objective approaches -, depending on whether they adopt the agent's or the engineer's viewpoint, respectively. We then claim that the two approaches have a deep and different impact on the way in which agent systems; axe modelled and built, and show two examples rooted in different models and technologies. Finally, we advocate that both approaches play a fundamental role in the engineering of agent systems, and that any methodology for the design and development of agent systems has to exploit both objective and subjective coordination models and technologies
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Information Systems: Editorial
No full textResearch efforts on structured data, multimedia, and services have involved non-overlapping communities. However, from a user perspective, the three kinds of information should behave and be accessed similarly. Instead, a user has to deal with different tools in order to gain a complete knowledge about a domain. There is no integrated view comprising data, multimedia and services retrieved by the specific tools that is automatically computed. A unified approach for dealing with different kinds of information may allow searches across different domains and different starting points / results in the searching processes.Multiple and challenging research issues have to be addressed to achieve this goal, including: mediating among different models for representing information, developing new techniques for extracting and mapping relevant information from heterogeneous kinds of data, devising innovative paradigms for formulating and processing queries ranging over both (multimedia) data and services, investigating new models for visualizing the results and allowing the user to easily manipulate them.This special issue "Semantic Integration of Data, Multimedia, and Services" presents advances in data, multimedia, and services interoperability
Extracting Relevant Attribute Values for Improved Search
No full textA 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 fully implemented prototype and some experimental results to show the effectiveness of "relevant values" when searching a knowledge base.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 fully implemented prototype and some experimental results to show the effectiveness of "relevant values" when searching a knowledge base. © 2007 IEEE
Datalog in Time and Space, Synchronously
Get PDFMotivated by recent developments of Datalog-based languages for highly distributed systems, in this paper we introduce a version of Datalog specifically tailored for distributed programming in synchronous settings, along with its operational and declarative semantics
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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