Now showing items 1-20 of 23

    • A situational approach for the definition and tailoring of a data-driven software evolution method 

      Franch Gutiérrez, Javier; Ralyté, Jolita; Perini, Anna; Abelló Gamazo, Alberto; Ameller, David; Gorroñogoitia, Jesús; Nadal Francesch, Sergi; Oriol Hilari, Marc; Seyff, Norbert; Siena, Alberto; Susi, Angelo (Springer, 2018)
      Conference report
      Open Access
      Successful software evolution heavily depends on the selection of the right features to be included in the next release. Such selection is difficult, and companies often report bad experiences about user acceptance. To ...
    • A software reference architecture for semantic-aware big data systems 

      Nadal Francesch, Sergi; Herrero Otal, Víctor; Romero Moral, Óscar; Abelló Gamazo, Alberto; Franch Gutiérrez, Javier; Vansummeren, Stijn; Valerio, Danilo (2016-06-13)
      Article
      Open Access
      Context: Big Data systems are a class of software systems that ingest, store, process and serve massive amounts of heterogeneous data, from multiple sources. Despite their undisputed impact in current society, their ...
    • An approach for alert raising in real-time data warehouses 

      López, Maximiliano Ariel; Nadal Francesch, Sergi; Djedaini, Mahfoud; Marcel, Patrick; Peralta, Verónika; Furtado, Pedro (2015)
      Conference report
      Open Access
      This work proposes an approach for alert raising within a real-time data warehouse environment. It is based on the calculation of confidence intervals for measures from historical facts. As new facts arrive to the data ...
    • An integration-oriented ontology to govern evolution in big data ecosystems 

      Nadal Francesch, Sergi; Romero Moral, Óscar; Abelló Gamazo, Alberto; Vassiliadis, Panos; Vansummeren, Stijn (CEUR-WS.org, 2017)
      Conference lecture
      Open Access
      Big Data architectures allow to flexibly store and process heterogeneous data, from multiple sources, in its original format. The structure of those data, commonly supplied by means of REST APIs, is continuously evolving, ...
    • An integration-oriented ontology to govern evolution in big data ecosystems 

      Nadal Francesch, Sergi; Romero Moral, Óscar; Abelló Gamazo, Alberto; Vassiliadis, Panos; Vansummeren, Stijn (2019-01)
      Article
      Open Access
      Big Data architectures allow to flexibly store and process heterogeneous data, from multiple sources, in their original format. The structure of those data, commonly supplied by means of REST APIs, is continuously evolving. ...
    • Big data management challenges in SUPERSEDE 

      Nadal Francesch, Sergi; Abelló Gamazo, Alberto; Romero Moral, Óscar; Varga, Jovan (CEUR-WS.org, 2017)
      Conference report
      Open Access
      The H2020 SUPERSEDE (www.supersede.eu) project aims to support decision-making in the evolution and adaptation of software services and applications by exploiting end-user feedback and runtime data, with the overall goal ...
    • DocDesign 2.0: Automated database design for document stores with multi-criteria optimization 

      Hewasinghage, Moditha Lakshan Dharmasir; Nadal Francesch, Sergi; Abelló Gamazo, Alberto (OpenProceedings, 2021)
      Conference lecture
      Open Access
      We present DocDesign 2.0, a novel system that supports database design for document stores. DocDesign 2.0 automatically generates a document store design driven by a query workload and a set of optimization objectives. In ...
    • Effective and scalable data discovery with NextiaJD 

      Flores Herrera, Javier de Jesús; Nadal Francesch, Sergi; Romero Moral, Óscar (OpenProceedings, 2021)
      Conference lecture
      Open Access
      We present NextiaJD, a data discovery system with high predictive performance and computational efficiency. NextiaJD aids data scientists in the discovery of datasets that can be crossed. To that end, it proposes a ranking ...
    • FAME: supporting continuous requirements elicitation by combining user feedback and monitoring 

      Oriol Hilari, Marc; Stade, Melanie; Fotrousi, Farnaz; Nadal Francesch, Sergi; Varga, Jovan; Seyff, Norbert; Abelló Gamazo, Alberto; Franch Gutiérrez, Javier; Marco Gómez, Jordi; Schmidt, Oleg (Institute of Electrical and Electronics Engineers (IEEE), 2018)
      Conference report
      Open Access
      Context: Software evolution ensures that software systems in use stay up to date and provide value for end-users. However, it is challenging for requirements engineers to continuously elicit needs for systems used by ...
    • Graph-driven federated data management 

      Nadal Francesch, Sergi; Abelló Gamazo, Alberto; Romero Moral, Óscar; Vansummeren, Stijn; Vassiliadis, Panos (2021-05-03)
      Article
      Open Access
      Modern data analysis applications, require the ability to provide on-demand integration of data sources while offering a flexible and user-friendly query interface. Traditional techniques for answering queries using views, ...
    • Integration-oriented ontology 

      Nadal Francesch, Sergi; Abelló Gamazo, Alberto (Springer, 2018-02-01)
      Part of book or chapter of book
      Open Access
      The purpose of an integration-oriented ontology is to provide a conceptualization of a domain of interest for automating the data integration of an evolving and heterogeneous set of sources using Semantic Web technologies. ...
    • Intermediate results materialization selection and format for data-intensive flows 

      Munir, Rana Faisal; Nadal Francesch, Sergi; Romero Moral, Óscar; Abelló Gamazo, Alberto; Jovanovic, Petar; Thiele, Maik; Lehner, Wolfgang (2018-05-01)
      Article
      Restricted access - publisher's policy
      Data-intensive flows deploy a variety of complex data transformations to build information pipelines from data sources to different end users. As data are processed, these workflows generate large intermediate results, ...
    • Materializing aaseline views for deviation detection exploratory OLAP 

      Furtado, Pedro; Nadal Francesch, Sergi; Peralta, Verónika; Djedaini, Mahfoud; Labroche, Nicolas; Marcel, Patrick (Springer, 2015)
      Conference report
      Open Access
      Alert-raising and deviation detection in OLAP and explora-tory search concerns calling the user’s attention to variations and non-uniform data distributions, or directing the user to the most interesting exploration of the ...
    • MDM: governing evolution in big data ecosystems 

      Nadal Francesch, Sergi; Abelló Gamazo, Alberto; Romero Moral, Óscar; Vansummeren, Stijn; Vassiliadis, Panos (OpenProceedings, 2018)
      Conference lecture
      Open Access
      On-demand integration of multiple data sources is a critical requirement in many Big Data settings. This has been coined as the data variety challenge, which refers to the complexity of dealing with an heterogeneous set ...
    • Metadata-driven data integration 

      Nadal Francesch, Sergi (Universitat Politècnica de Catalunya, 2019-05-16)
      Doctoral thesis
      Open Access
      Data has an undoubtable impact on society. Storing and processing large amounts of available data is currently one of the key success factors for an organization. Nonetheless, we are recently witnessing a change represented ...
    • Multi-Objective Materialized View Selection in Data-Intensive Flows 

      Nadal Francesch, Sergi (Universitat Politècnica de Catalunya, 2015-09-04)
      Master thesis
      Open Access
      In this thesis we present Forge, a tool for automating multi-objective materialization of intermediate results in data-intensive flows, driven by a set of different quality objectives. We report initial evaluation results, ...
    • ODIN: A dataspace management system 

      Nadal Francesch, Sergi; Rabbani, Kashif; Romero Moral, Óscar; Nigatu, Shumet Tadesse (CEUR-WS.org, 2019)
      Conference lecture
      Open Access
      ODIN is a system that supports the incremental pay-as-you-go integration of data sources into dataspaces and provides user-friendly querying mechanisms on top of them. We describe its main characteristics and underlying ...
    • On the performance impact of using JSON, beyond impedance mismatch 

      Hewasinghage, Moditha Lakshan Dharmasir; Nadal Francesch, Sergi; Abelló Gamazo, Alberto (Springer, 2020)
      Conference report
      Open Access
      NOSQL database management systems adopt semi-structured data models, such as JSON, to easily accommodate schema evolution and overcome the overhead generated from transforming internal structures to tabular data (i.e., ...
    • Quarry 

      Abelló Gamazo, Alberto; Romero Moral, Óscar; Jovanovic, Petar; Nadal Francesch, Sergi; Bilalli, Besim; Candón Arenas, Héctor; Mayorova, Daria; Thavornun, Varunya; Gil González, Daniel (2015-07-01)
      Software
      Restricted access - confidentiality agreement
    • Quarry : digging up the gems of your data treasury 

      Jovanovic, Petar; Romero Moral, Óscar; Simitsis, Alkis; Abelló Gamazo, Alberto; Candón Arenas, Héctor; Nadal Francesch, Sergi (2015)
      Conference lecture
      Open Access
      The design lifecycle of a data warehousing (DW) system is primarily led by requirements of its end-users and the complexity of underlying data sources. The process of designing a multidimensional (MD) schema and back-end ...