• Aggregated 2D range queries on clustered points 

      Bernardo, Guillermo de; Konow, Bernardo; Navarro, Gonzalo; Brisaboa, Nieves R.; Seco, Diego (Elsevier Ltd, 2016-09)
      [Abstract] Efficient processing of aggregated range queries on two-dimensional grids is a common requirement in information retrieval and data mining systems, for example in Geographic Information Systems and OLAP cubes. ...
    • An Action Research for Improving the Sustainability Assessment Framework Instruments 

      Condori Fernández, Nelly; Lago, Patricia; Rodríguez Luaces, Miguel; Saavedra Places, Ángeles (MDPI AG, 2020-02-24)
      [Abstract] In the last years, software engineering researchers have defined sustainability as a quality requirement of software, but not enough effort has been devoted to develop new methods/techniques to support the ...
    • An Architecture for Software Engineering Gamification 

      Pedreira, Óscar; García, Félix; Piattini, Mario; Cortiñas, Alejandro; Cerdeira-Pena, Ana (Qinghua Daxue Xuebao Bianjibu,Tsinghua University, Editorial Board, 2020-05-07)
      [Abstract] Gamification has been applied in software engineering to improve quality and results by increasing people's motivation and engagement. A systematic mapping has identified research gaps in the field, one of them ...
    • An Efficient Representation of Enriched Temporal Trajectories 

      Brisaboa, Nieves R.; Fariña, Antonio; Otero-González, Diego; Varela Rodeiro, Tirso (SciTePress, 2021)
      [Abstract] We present a novel representation of enriched trajectories of a mobile workforce management system. In this system, employees are tracked during their working day and both their routes and the tasks performed ...
    • An index for moving objects with constant-time access to their compressed trajectories 

      Brisaboa, Nieves R.; Gagie, Travis; Gómez-Brandón, Adrián; Navarro, Gonzalo; Paramá, José R. (Taylor & Francis, 2021)
      [Abstract]: As the number of vehicles and devices equipped with GPS technology has grown explosively, an urgent need has arisen for time- and space-efficient data structures to represent their trajectories. The most commonly ...
    • Augmented Thresholds for MONI 

      Martínez-Guardiola, César; Brown, Nathaniel K.; Silva-Coira, Fernando; Köppl, Dominik; Gagie, Travis; Ladra, Susana (Institute of Electrical and Electronics Engineers Inc., 2023)
      [Abstract]: MONI (Rossi et al., 2022) can store a pangenomic dataset T in small space and later, given a pattern P, quickly find the maximal exact matches (MEMs) of P with respect to T. In this paper we consider its one-pass ...
    • Automatic group-wise whole-brain short association fiber bundle labeling based on clustering and cortical surface information 

      Vázquez, Andrea; López-López, Narciso; Houenou, Josselin; Poupon, Cyril; Mangin, Jean-François; Ladra, Susana; Guevara, Pamela (BioMed Central Ltd., 2020-06-03)
      [Abstract] Background Diffusion MRI is the preferred non-invasive in vivo modality for the study of brain white matter connections. Tractography datasets contain 3D streamlines that can be analyzed to study the main ...
    • Boosting Perturbation-Based Iterative Algorithms to Compute the Median String 

      Mirabal, Pedro; Abreu Salas, José Ignacio; Seco, Diego; Pedreira, Óscar; Chávez, Edgar (IEEE, 2021)
      [Abstract] The most competitive heuristics for calculating the median string are those that use perturbation-based iterative algorithms. Given the complexity of this problem, which under many formulations is NP-hard, the ...
    • Combining Multiple Granularity Variability in a Software Product Line Approach for Web Engineering 

      Horcas Aguilera, José Miguel; Cortiñas, Alejandro; Fuentes, Lidia; Rodríguez Luaces, Miguel (Elsevier, 2022)
      [Abstract] Context: Web engineering involves managing a high diversity of artifacts implemented in different languages and with different levels of granularity. Technological companies usually implement variable artifacts ...
    • Compact and indexed representation for LiDAR point clouds 

      Ladra, Susana; Rodríguez Luaces, Miguel; Paramá, José R.; Silva-Coira, Fernando (Taylor & Francis, 2022)
      [Abstract]: LiDAR devices are capable of acquiring clouds of 3D points reflecting any object around them, and adding additional attributes to each point such as color, position, time, etc. LiDAR datasets are usually large, ...
    • Compact Trip Representation over Networks 

      Brisaboa, Nieves R.; Fariña, Antonio; Galaktionov, Daniil; Rodríguez, M. Andrea (Springer, 2016-09-21)
      [Abstract] We present a new Compact Trip Representation ( CTRCTR ) that allows us to manage users’ trips (moving objects) over networks. These could be public transportation networks (buses, subway, trains, and so on) where ...
    • Compressed and queryable self-indexes for RDF archives 

      Cerdeira-Pena, Ana; Bernardo, Guillermo de; Fariña, Antonio; Fernández, Javier D.; Martínez-Prieto, Miguel A. (Springer Nature, 2023-08)
      [Abstract]: RDF compression and querying are consolidated topics in the Web of Data, with a plethora of solutions to efficiently store and query static datasets. However, as RDF data changes along time, it becomes necessary ...
    • Compressed Data Structures for Binary Relations in Practice 

      Quijada Fuentes, Carlos; Penabad, Miguel R.; Ladra, Susana; Gutiérrez Retamal, Gilberto (Institute of Electrical and Electronics Engineers, 2020-01-31)
      [Abstract] Binary relations are commonly used in Computer Science for modeling data. In addition to classical representations using matrices or lists, some compressed data structures have recently been proposed to represent ...
    • Design of Mutation Operators for Testing Geographic Information Systems 

      Alvarado, Suilen H. (M D P I AG, 2019-08-06)
      [Abstract] In this article, we propose the definition of specific mutation operators for testing Geographic Information Systems. We describe the process for applying the operators and generating mutants, and present a case ...
    • Efficient and Compact Representations of Some Non-canonical Prefix-Free Codes 

      Fariña, Antonio; Gagie, Travis; Manzini, Giovanni; Navarro, Gonzalo; Ordóñez, Alberto (Springer, 2016-09-21)
      [Abstract] For many kinds of prefix-free codes there are efficient and compact alternatives to the traditional tree-based representation. Since these put the codes into canonical form, however, they can only be used when ...
    • Efficient Processing of Raster and Vector Data 

      Silva-Coira, Fernando; Paramá, José R.; Ladra, Susana; López, Juan R.; Gutiérrez, Gilberto (Public Library of Science, 2020-01-10)
      [Abstract] In this work, we propose a framework to store and manage spatial data, which includes new efficient algorithms to perform operations accepting as input a raster dataset and a vector dataset. More concretely, we ...
    • Efficient Representation of Multidimensional Data over Hierarchical Domains 

      Brisaboa, Nieves R.; Cerdeira-Pena, Ana; López López, Narciso; Navarro, Gonzalo; Penabad, Miguel R.; Silva-Coira, Fernando (Springer, 2016-09-21)
      [Abstract] We consider the problem of representing multidimensional data where the domain of each dimension is organized hierarchically, and the queries require summary information at a different node in the hierarchy of ...
    • Energy Consumption in Compact Integer Vectors: A Study Case 

      Fuentes Sepúlveda, José; Ladra, Susana (Institute of Electrical and Electronics Engineers, 2019-10-25)
      [Abstract] In the field of algorithms and data structures analysis and design, most of the researchers focus only on the space/time trade-off, and little attention has been paid to energy consumption. Moreover, most of the ...
    • Exploiting Computation-Friendly Graph Compression Methods for Adjacency-Matrix Multiplication 

      Francisco, Alexandre P.; Gagie, Travis; Ladra, Susana; Navarro, Gonzalo (IEEE Computer Society, 2018-03)
      [Abstract] Computing the product of the (binary) adjacency matrix of a large graph with a real-valued vector is an important operation that lies at the heart of various graph analysis tasks, such as computing PageRank. In ...
    • Extending general compact querieable representations to GIS applications 

      Brisaboa, Nieves R.; Cerdeira-Pena, Ana; Bernardo, Guillermo de; Navarro, Gonzalo; Pedreira, Óscar (Elsevier, 2020-01)
      [Abstract]: The raster model is commonly used for the representation of images in many domains, and is especially useful in Geographic Information Systems (GIS) to store information about continuous variables of the space ...