Benoit Groz: Filtering with the Crowd in the CrowdScreen model

When: Friday, March 7, at 14.00

Where: PCRI building, room 445

Who: Benoit Groz

Title: Filtering with the Crowd in the CrowdScreen model

Abstract:
Filtering a set of items -to select photographs presenting certain properties for instance- is a common application of Crowd-Sourcing.
When the workers are error-prone, each item is presented to multiple users, to limit the probability of misclassification. Since the Crowd is a relatively expensive resource, minimizing the number of questions per item may naturally result in big savings. Several algorithms to address this minimization problem have been presented in the CrowdScreen framework by Parameswaran et al. However, those algorithms do not scale well and therefore cannot be used in scenarios where high accuracy is required in spite of high user error rates.
We propose optimizations of those as well as new theoretical insights that lead to scalable filtering algorithms.

Permanent link to this article: https://team.inria.fr/oak/2014/03/07/benoit-groz-filtering-with-the-crowd-in-the-crowdscreen-model/

Benjamin Nguyen: Privacy-Preserving Query Execution using a Decentralized Architecture and Tamper Resistant Hardware

When: Tuesday, March 4, at 14.00

Where: PCRI building, room 455

Who: Benjamin Nguyen

Title: Privacy-Preserving Query Execution using a Decentralized Architecture and Tamper Resistant Hardware

Abstract:
Current applications, from complex sensor systems (e.g. quantified self) to online e-markets acquire vast quantities of personal information which usually ends-up on central servers. Decentralized architectures, devised to help individuals keep full control of their data, hinder global treatments and queries, impeding the development of services of great interest. This paper promotes the idea of pushing the security to the edges of applications, through the use of secure hardware devices controlling the data at the place of their acquisition. To solve this problem, we propose secure distributed querying protocols based on the use of a tangible physical element of trust, reestablishing the capacity to perform global computations without revealing any sensitive information to central servers. There are two main problems when trying to support SQL in this context: perform joins and perform aggregations. In this paper, we study the subset of SQL queries without joins and show how to secure their execution in the presence of honest-but-curious attackers. Cost models and experiments demonstrate that this approach can scale to nationwide infrastructures.

Joint work with Quoc-Cuong To and Philippe Pucheral.

Permanent link to this article: https://team.inria.fr/oak/2014/03/04/benjamin-nguyen-privacy-preserving-query-execution-using-a-decentralized-architecture-and-tamper-resistant-hardware/

OAK visits the Pilgrim team at IRISA

Alexandra, Damian and Ioana met François at Lannion to discuss our current research paper.

We visited both the paper’s related works and the location’s related scenery.

The view from our hotel was breathtaking.

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As we arrived at Perros-Guirec, François had pre-ordered a rainbow for us.

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Next, we had a great time exploring the landscape.

It may have been a “tad” windy, but we pretended not to notice 🙂

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Needless to say, plans were made to return this summer.

Permanent link to this article: https://team.inria.fr/oak/2014/03/03/oak-visits-the-pilgrim-team-at-irisa/

Extended Abstract at CHI’14

“A Three-dimensional Mirror Augmented by Medical Imaging: Questioning Self-portraying at the Limit of Intimacy”
by Tom Giraud, Matthieu Courgeon, Marion Tardieu, Alexandra Roatis and Xavier Maitre will appear in
CHI ’14 Extended Abstracts: ACM SIGCHI Conference on Human Factors in Computing Systems Proceedings

Permanent link to this article: https://team.inria.fr/oak/2014/02/24/extended-abstract-at-chi14/

SIGMOD 2014 Tutorial: Cloud-based RDF data management

The tutorial “Cloud-based RDF data management”, by Zoi Kaoudi and Ioana Manolescu, has been accepted for presentation at SIGMOD 2014

Permanent link to this article: https://team.inria.fr/oak/2014/02/13/sigmod-2014-tutorial-cloud-based-rdf-data-management/

SIGMOD 2014: Complete Yet Practical Search for Minimal Query Reformulations Under Constraints

The paper “Complete Yet Practical Search for Minimal Query Reformulations Under Constraints”, by Ioana Ileana, Bogdan Cautis, Alin Deutsch and Yannis Katsis has been accepted for publication in SIGMOD 2014.

Permanent link to this article: https://team.inria.fr/oak/2014/02/11/sigmod-2014-complete-yet-practical-search-for-minimal-query-reformulations-under-constraints/

Laurent Daynès: Implementing language in Java with Alphabet Soup: how it may impact the Oracle Database

When: Thursday, February 6, at 15.00

Where: PCRI building, room 445

Who: Laurent Daynès, Oracle Labs

Title: Implementing language in Java with Alphabet Soup: how it may impact the Oracle Database

Permanent link to this article: https://team.inria.fr/oak/2014/02/06/laurent-daynes-implementing-language-in-java-with-alphabet-soup-how-it-may-impact-the-oracle-database/

ODIN (Open Data Intelligence) project accepted

The ODIN (Open Data Intelligence) project, coordinated by SemSoft, with IRISA / ENSSAT / U. Rennes 1 and OAK has been accepted by the DGA. The project aims at building a complete processing chain for multidimensional analysis of RDF data.

Permanent link to this article: https://team.inria.fr/oak/2014/01/28/odin-open-data-intelligence-project-accepted/

Jesús Camacho-Rodríguez: PAXQuery : Efficient Parallel Processing of Complex XQuery

10.00, room 455, PCRI

Abstract
Increasing volumes of data are being produced and exchanged over the Web, in particular in tree-structured formats such as XML or JSON. This leads to a need of highly scalable algorithms and tools for processing such data, capable to take advantage of massively parallel processing frameworks.

This work considers the problem of efficiently parallelizing the execution of complex nested data processing, expressed in XQuery. We provide novel algorithms showing how to translate such queries into PACT, a recent framework generalizing MapReduce in particular by supporting many-input tasks. We present the first formal translation of complex XQuery algebraic expressions into PACT plans, and demonstrate experimentally the efficiency and scalability of our approach.

Permanent link to this article: https://team.inria.fr/oak/2014/01/13/jesus-camacho-rodriguez-paxquery-efficient-parallel-processing-of-complex-xquery/

Luca Cabibbo: NoSQL Database Design for Next-Generation Web Applications

When: Friday, January 10, at 14.00

Where: PCRI building, room 445

Who: Luca Cabibbo, Università Roma Tre

Title: NoSQL Database Design for Next-Generation Web Applications

Abstract:
NoSQL database systems especially support the development of next-generation web applications, for which: (i) data of interest have a flexible structure, (ii) data access is based on simple read-write operations, (iii) foremost quality requirements are good horizontal scalability, response time, and availability, as well as a certain degree of consistency.

Although NoSQL databases are claimed to be “schemaless,” the design of data organization requires important decisions, to map application data to the modeling elements (collections, tables, documents, key-value pairs) available in the target datastore.
These decisions are significant, because of their impact on the above major quality requirements.
Given the high heterogeneity in the NoSQL world, this design activity is usually based on best practices and guidelines that are strictly related to the selected system, but with no systematic methodology.

In this talk we present NoAM (NoSQL Abstract Model), a logical approach to NoSQL database design, with initial activities that are independent of the specific target system.
The approach aims at exploiting the commonalities of the various NoSQL datastores.
It is based on an intermediate, abstract data model, to represent application data as collections of complex-value objects, called aggregates.
Aggregates are units of distribution (to support scalability) and consistency (to the extent it is needed); aggregates can be partitioned in smaller data elements (for the sake of performance).
The intermediate representation can be then implemented in target NoSQL systems, taking into account their specific features.

We then present ONDM (Object-NoSQL Datastore Mapper), a framework that supports the management of persistent objects in NoSQL database systems.
It provides application developers with a uniform programming interface, as well as the ability to map application data to different data representations, in a flexible way, towards a variety of NoSQL systems.
In particular, ONDM can be used to support developers in performing experiments that are usually needed during the design of a NoSQL database, to assess the most suitable design solution among a set of valid candidate (but alternative) representations.

Slides
Luca Cabibbo: NoSQL Database Design for Next-Generation Web Applications

Permanent link to this article: https://team.inria.fr/oak/2014/01/10/luca-cabibbo-nosql-database-design-for-next-generation-web-applications/