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Displaying 1-38 out of 38 total
A Data Privacy Service for Structured P2P Systems
Found in: Mexican International Conference on Computer Science
By Mohamed Jawad, Patricia Serrano-Alvarado, Patrick Valduriez, Stéphane Drapeau
Issue Date:September 2009
pp. 45-56
Online peer-to-peer (P2P) communities such as professional ones (e.g., medical or research) are becoming popular due to increasing needs on data sharing. P2P environments offer valuable characteristics but limited guarantees when sharing sensitive or confi...
 
Efficient Evaluation of SUM Queries over Probabilistic Data
Found in: IEEE Transactions on Knowledge and Data Engineering
By Reza Akbarinia,Patrick Valduriez,Guillaume Verger
Issue Date:April 2013
pp. 764-775
SUM queries are crucial for many applications that need to deal with uncertain data. In this paper, we are interested in the queries, called ALL_SUM, that return all possible sum values and their probabilities. In general, there is no efficient solution fo...
 
StreamCloud: An Elastic and Scalable Data Streaming System
Found in: IEEE Transactions on Parallel and Distributed Systems
By Vincenzo Gulisano,Ricardo Jiménez-Peris,Marta Patiño-Martínez,Claudio Soriente,Patrick Valduriez
Issue Date:December 2012
pp. 2351-2365
Many applications in several domains such as telecommunications, network security, large-scale sensor networks, require online processing of continuous data flows. They produce very high loads that requires aggregating the processing capacity of many nodes...
 
Distributed data management in 2020?
Found in: Data Engineering, International Conference on
By M. Tamer Ozsu,Patrick Valduriez,Serge Abiteboul,Bettina Kemme,Ricardo Jimenez-Peris,Beng Chin Ooi
Issue Date:April 2011
pp. 1360
Work on distributed data management commenced shortly after the introduction of the relational model in the mid-1970's. 1970's and 1980's were very active periods for the development of distributed relational database technology, and claims were made that ...
 
Energy Efficient Data Access in Mobile P2P Networks
Found in: IEEE Transactions on Knowledge and Data Engineering
By Kwangjin Park,Patrick Valduriez
Issue Date:November 2011
pp. 1619-1634
A fundamental problem for peer-to-peer (P2P) applications in mobile-pervasive computing environment is to efficiently identify the node that stores particular data items and download them while preserving battery power. In this paper, we propose a P2P Mini...
 
StreamCloud: A Large Scale Data Streaming System
Found in: Distributed Computing Systems, International Conference on
By Vincenzo Gulisano, Ricardo Jimenez-Peris, Marta Patino-Martinez, Patrick Valduriez
Issue Date:June 2010
pp. 126-137
Data streaming has become an important paradigm for the real-time processing of continuous data flows in domains such as finance, telecommunications, networking, Some applications in these domains require to process massive data flows that current technolo...
 
Scalable P2P Reconciliation Infrastructure for Collaborative Text Editing
Found in: Advances in Databases, First International Conference on
By Mounir Tlili, Reza Akbarinia, Esther Pacitti, Patrick Valduriez
Issue Date:April 2010
pp. 155-164
We address the problem of optimistic replication forcollaborative text editing in Peer-to-Peer (P2P) systems. This problem is challenging because of concurrent updating at multiple peers and dynamic behavior of peers. Operationaltransformation (OT) is a ty...
 
Real-Time Support for Software Transactional Memory
Found in: Real-Time Computing Systems and Applications, International Workshop on
By Toufik Sarni, Audrey Queudet, Patrick Valduriez
Issue Date:August 2009
pp. 477-485
Transactional memory is currently a hot research topic, having attracted the focus of both academic researchers and development groups at companies. Indeed, the concept of transactional memory has recently attracted much interest for multicore systems as i...
 
SbQA: A Self-Adaptable Query Allocation Process
Found in: Data Engineering, International Conference on
By Jorge-Arnulfo Quiané-Ruiz, Philippe Lamarre, Patrick Valduriez
Issue Date:April 2009
pp. 1527-1530
We present a flexible query allocation framework, called Satisfaction-based Query Allocation (SbQA for short), for distributed information systems where both consumers and providers (the participants) have special interests towards queries. A particularity...
 
A Framework for Testing Peer-to-Peer Systems
Found in: Software Reliability Engineering, International Symposium on
By Eduardo Cunha de Almeida, Gerson Sunyé, Yves Le Traon, Patrick Valduriez
Issue Date:November 2008
pp. 167-176
Developing peer-to-peer (P2P) systems is hard because they must be deployed on a high number of nodes, which can be autonomous, refusing to answer to some requests or even unexpectedly leaving the system. Such volatility of nodes is a common behavior in P2...
 
DiSC: Benchmarking Secure Chip DBMS
Found in: IEEE Transactions on Knowledge and Data Engineering
By Nicolas Anciaux, Luc Bouganim, Philippe Pucheral, Patrick Valduriez
Issue Date:October 2008
pp. 1363-1377
Secure chips, e.g. present in smart cards, USB dongles, i-buttons, are now ubiquitous in applications with strong security requirements. And they require embedded data management techniques. However, secure chips have severe hardware constraints which make...
 
Reconciliation in the APPA P2P System
Found in: Parallel and Distributed Systems, International Conference on
By Vidal Martins, Reza Akbarinia, Esther Pacitti, Patrick Valduriez
Issue Date:July 2006
pp. 401-410
In Peer-to-peer (P2P) systems, there has been little work on managing data replication in the presence of updates. However, important P2P applications that involve collaboration require multi-master replication support. In this paper, we adopt optimistic r...
 
Physical and Virtual Partitioning in OLAP Database Clusters
Found in: Computer Architecture and High Performance Computing, Symposium on
By Camille Furtado, Alexandre A. B. Lima, Esther Pacitti, Patrick Valduriez, Marta Mattoso
Issue Date:October 2005
pp. 143-150
On-line analytical processing (OLAP) applications require high performance database support to achieve good response time (crucial for decision making). Database clusters provide a cost-effective alternative to parallel database systems. For OLAP applicati...
 
Consistency Management for Partial Replication in a High Performance Database Cluster
Found in: Parallel and Distributed Systems, International Conference on
By Cédric Coulon, Esther Pacitti, Patrick Valduriez
Issue Date:July 2005
pp. 809-815
<p>In a database cluster, preventive replication can provide strong consistency without the limitations of synchronous replication. However, the original proposal [9] assumes full replication and has performance limitations. In this paper, we address...
 
Processing Queries with Expensive Functions and Large Objects in Distributed Mediator Systems
Found in: Data Engineering, International Conference on
By Luc Bouganim, Françoise Fabret, Fabio Porto, Patrick Valduriez
Issue Date:April 2001
pp. 0091
Abstract: LeSelect is a mediator system which allows scientists to publish their resources (data and programs) so they can be transparently accessed. The scientists can typically issue queries which access distributed published data and involve the executi...
 
Dynamic Query Scheduling in Data Integration Systems
Found in: Data Engineering, International Conference on
By Luc Bouganim, Françoise Fabret, Patrick Valduriez, C. Mohan
Issue Date:March 2000
pp. 425
Execution plans produced by traditional query optimizers for data integration queries may yield poor performance for several reasons. The cost estimates may be inaccurate, the memory available at run-time may be insufficient, or data delivery rate can be u...
 
Scaling Access to Heterogeneous Data Sources with DISCO
Found in: IEEE Transactions on Knowledge and Data Engineering
By Anthony Tomasic, Louiqa Raschid, Patrick Valduriez
Issue Date:September 1998
pp. 808-823
<p><b>Abstract</b>—Accessing many data sources aggravates problems for users of heterogeneous distributed databases. Database administrators must deal with <it>fragile mediators</it>, that is, mediators with schemas and views ...
 
Benchmarking the DBS3 Parallel Query Optimizer
Found in: IEEE Concurrency
By Mohamed Zaït, Daniela Florescu, Patrick Valduriez
Issue Date:June 1996
pp. 26-40
The authors designed and implemented the DBS3 optimizer along three dimensions: search space, search strategy, and cost model. (The DBS3, or Database System on Shared Store, is a shared-memory prototype implemented on an Encore Multimax multiprocessor as p...
 
Distributed Database Systems: Where Are We Now?
Found in: Computer
By M. Tamer Özsu, Patrick Valduriez
Issue Date:August 1991
pp. 68-78
<p>The authors explain what is meant by a distributed database system and discuss its characteristics. They survey the state of distributed database technology, focusing on how well products meet the goals of transparent management of distributed and...
 
WebSmatch: a tool for open data
Found in: Proceedings of the 2nd International Workshop on Open Data (WOD '13)
By Christian Frisch, Emmanuel Castanier, Patrick Valduriez, Remi Coletta
Issue Date:June 2013
pp. 1-2
Working with open data sources can yield high value information but raises major problems in terms of metadata extraction, data source integration and visualization. In this paper we describe a demonstration of WebSmatch, a flexible environment for Web dat...
     
Evaluating parameter sweep workflows in high performance computing
Found in: Proceedings of the 1st ACM SIGMOD Workshop on Scalable Workflow Execution Engines and Technologies (SWEET '12)
By Daniel de Oliveira, Eduardo Ogasawara, Fábio Porto, Fernando Chirigati, Jonas Dias, Marta Mattoso, Patrick Valduriez, Vítor Silva
Issue Date:May 2012
pp. 1-10
Scientific experiments based on computer simulations can be defined, executed and monitored using Scientific Workflow Management Systems (SWfMS). Several SWfMS are available, each with a different goal and a different engine. Due to the exploratory analysi...
     
Public data integration with WebSmatch
Found in: Proceedings of the First International Workshop on Open Data (WOD '12)
By Christian Frisch, DuyHoa Ngo, Emmanuel Castanier, Patrick Valduriez, Remi Coletta, Zohra Bellahsene
Issue Date:May 2012
pp. 5-12
Integrating open data sources can yield high value information but raises major problems in terms of metadata extraction, data source integration and visualization of integrated data. In this paper, we describe WebSmatch, a flexible environment for Web dat...
     
ParallelGDB: a parallel graph database based on cache specialization
Found in: Proceedings of the 15th Symposium on International Database Engineering & Applications (IDEAS '11)
By David Dominguez-Sal, Luis Barguno, Patrick Valduriez, Victor Muntes-Mulero
Issue Date:September 2011
pp. 162-169
The need for managing massive attributed graphs is becoming common in many areas such as recommendation systems, proteomics analysis, social network analysis or bibliographic analysis. This is making it necessary to move towards parallel systems that allow...
     
Distributed processing of continuous join queries using DHT networks
Found in: Proceedings of the 2009 EDBT/ICDT Workshops (EDBT/ICDT '09)
By Esther Pacitti, Patrick Valduriez, Reza Akbarinia, Wenceslao Palma
Issue Date:March 2009
pp. 34-41
This paper addresses the problem of computing approximate answers to continuous join queries. We present a new method, called DHTJoin, which combines hash-based placement of tuples in a Distributed Hash Table (DHT) and dissemination of queries exploiting t...
     
Mobile continuous nearest neighbor queries on air
Found in: Proceedings of the 16th ACM SIGSPATIAL international conference on Advances in geographic information systems (GIS '08)
By Hyunseung Choo, KwangJin Park, Patrick Valduriez
Issue Date:November 2008
pp. 1-8
In this paper, we propose new spatial query processing algorithms to support Mobile Continuous Nearest Neighbor Query (MCNNQ) in wireless broadcast environments. Each client (object) computes individually the function that best captures the locations of th...
     
Action synchronization in P2P system testing
Found in: Proceedings of the 2008 international workshop on Data management in peer-to-peer systems (DaMaP '08)
By Eduardo Cunha de Almeida, Gerson Sunye, Patrick Valduriez
Issue Date:March 2008
pp. 43-49
Testing peer-to-peer (P2P) systems is difficult because of the high numbers of nodes which can be heterogeneous and volatile. A test case may be composed of several ordered actions that may be executed on different nodes. To ensure action ordering and the ...
     
Dealing with P2P semantic heterogeneity through query expansion and interpretation
Found in: Proceedings of the 2008 international workshop on Data management in peer-to-peer systems (DaMaP '08)
By Anthony Ventresque, Patrick Valduriez, Philippe Lamarre, Sylvie Cazalens
Issue Date:March 2008
pp. 3-10
In P2P systems where query initiators and information providers do not necessarily share the same ontology, semantic interoperability generally relies on ontology matching or schema mappings. Information exchange is then not only enabled by the established...
     
Design of PriServ, a privacy service for DHTs
Found in: Proceedings of the 2008 international workshop on Privacy and anonymity in information society (PAIS '08)
By Mohamed Jawad, Patricia Serrano Alvarado, Patrick Valduriez
Issue Date:March 2008
pp. 34-38
By decentralizing control, P2P systems provide efficient, scalable data sharing. However, when sharing data for different purposes (e.g., billing, purchase, shipping, etc.), data privacy can be easily violated by untrustworthy peers wich may use data for o...
     
Summary management in P2P systems
Found in: Proceedings of the 11th international conference on Extending database technology: Advances in database technology (EDBT '08)
By Guillaume Raschia, Noureddine Mouaddib, Patrick Valduriez, Rabab Hayek
Issue Date:March 2008
pp. 1-3
Sharing huge, massively distributed databases in P2P systems is inherently difficult. As the amount of stored data increases, data localization techniques become no longer sufficient. A practical approach is to rely on compact database summaries rather tha...
     
Data currency in replicated DHTs
Found in: Proceedings of the 2007 ACM SIGMOD international conference on Management of data (SIGMOD '07)
By Esther Pacitti, Patrick Valduriez, Reza Akbarinia
Issue Date:June 2007
pp. 211-222
Distributed Hash Tables (DHTs) provide a scalable solution for data sharing in P2P systems. To ensure high data availability, DHTs typically rely on data replication, yet without data currency guarantees. Supporting data currency in replicated DHTs is diff...
     
Semi-automatic model integration using matching transformations and weaving models
Found in: Proceedings of the 2007 ACM symposium on Applied computing (SAC '07)
By Marcos Didonet Del Fabro, Patrick Valduriez
Issue Date:March 2007
pp. 963-970
Model transformations are at the heart of model driven engineering (MDE) and can be used in many different application scenarios. For instance, model transformations are used to integrate very large models. As a consequence, they are becoming more and more...
     
Memory-adaptive scheduling for large query execution
Found in: Proceedings of the seventh international conference on Information and knowledge management (CIKM '98)
By Luc Bouganim, Olga Kapitskaia, Patrick Valduriez
Issue Date:November 1998
pp. 105-115
This paper focuses on the consistency issues related to integrating multiple sets of spatial data in spatial information systems such as Geographic Information Systems (GISs). Data sets to be integrated are assumed to hold information about the same geogra...
     
Transaction chopping: algorithms and performance studies
Found in: ACM Transactions on Database Systems (TODS)
By Dennis Shasha, Eric Simon, Francois Llirbat, Patrick Valduriez
Issue Date:March 1988
pp. 325-363
Chopping transactions into pieces is good for performance but may lead to nonserializable executions. Many researchers have reacted to this fact by either inventing new concurrency-control mechanisms, weakening serializability, or both. We adopt a differen...
     
Join indices
Found in: ACM Transactions on Database Systems (TODS)
By Patrick Valduriez
Issue Date:June 1987
pp. 218-246
In new application areas of relational database systems, such as artificial intelligence, the join operator is used more extensively than in conventional applications. In this paper, we propose a simple data structure, called a join index, for improving th...
     
A multikey hashing scheme using predicate trees
Found in: Proceedings of the 1984 ACM SIGMOD international conference on Management of data (SIGMOD '84)
By Patrick Valduriez, Yann Viemont
Issue Date:June 1984
pp. 107-114
A new method for multikey access suitable for dynamic files is proposed that transforms multiple key values into a logical address This method is based on a new structure, called predicate tree, that represents the function applied to several keys A predic...
     
Design and implementation of an extendible integrity subsystem
Found in: Proceedings of the 1984 ACM SIGMOD international conference on Management of data (SIGMOD '84)
By Eric Simon, Patrick Valduriez
Issue Date:June 1984
pp. 9-17
Tnls paper presents a powerful integrrty subsystem, which is implemented in the SABRE database system. The specification language is simple. Tne enforcement algorithm is general, in particular, it handles referential dependency and temporal assertions. Spe...
     
Join and Semijoin Algorithms for a Multiprocessor Database Machine
Found in: ACM Transactions on Database Systems (TODS)
By Georges Gardarin, Patrick Valduriez
Issue Date:March 1984
pp. 133-161
This paper presents and analyzes algorithms for computing joins and semijoins of relations in a multiprocessor database machine. First, a model of the multiprocessor architecture is described, incorporating parameters defining I/O, CPU, and message transmi...
     
Semi-join algorithms for multiprocessor systems
Found in: Proceedings of the 1982 ACM SIGMOD international conference on Management of data (SIGMOD '82)
By Patrick Valduriez
Issue Date:June 1982
pp. 225-233
Semi-join is a relational operator that decreases the cost of processing queries involving binary operations. This is accomplished by initially selecting the data relevant to answer the queries and thereby reducing the size of the operand relations. This p...
     
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