41 Hits in 4.3 sec

Computational methods and optimizations for containment and complementarity in web data cubes

Marios Meimaris, George Papastefanatos, Panos Vassiliadis, Ioannis Anagnostopoulos
2018 Information Systems  
In this paper we define two types of relationships between multidimensional RDF data, and we propose algorithms for efficient and scalable computation of these relationships.  ...  Specifically, we define the notions of containment and complementarity between points in multidimensional dataspaces, as different aspects of relatedness, and we propose a baseline method for computing  ...  In this paper, we address the problem of efficiently computing containment and complementarity between RDF observations, extending the preliminary work presented in [22] .  ... 
doi:10.1016/ fatcat:xtzdi5t6fvcnxhzz7czyhs3cxy

Quantifying the Connectivity of a Semantic Warehouse and Understanding its Evolution over Time

Michalis Mountantonakis, Nikos Minadakis, Yannis Marketakis, Pavlos Fafalios, Yannis Tzitzikas
2016 International Journal on Semantic Web and Information Systems (IJSWIS)  
In this paper we describe the corresponding requirements and challenges, and we focus on the aspects of quality and value of the warehouse.  ...  Consequently, these metrics can be used for advancing data/endpoint profiling and for this reason we use an extension of VoID (for making them publishable).  ...  To represent the statistics, they use VoID and the RDF Data Cube Vocabulary.  ... 
doi:10.4018/ijswis.2016070102 fatcat:ks2hdn2wmze6vpvr6lrie5dkzy

Charaterizing RDF graphs through graph-based measures – framework and assessment

Matthäus Zloch, Maribel Acosta, Daniel Hienert, Stefan Conrad, Stefan Dietze, Aidan Hogan
2020 Semantic Web Journal  
However, some of them are redundant, computationally expensive, and not meaningful enough to describe RDF graphs.  ...  In this work, we address the problem of identifying a minimal set of measures that is efficient, essential (non-redundant), and meaningful.  ...  Problem statement Computing arbitrary graph measures for RDF graphs is computationally expensive.  ... 
doi:10.3233/sw-200409 fatcat:m5qargillvfp7pxisihn4jut2i

Paving the Way for Interoperability in Digital Libraries: The Project

Katerina El Raheb, George Athanasopoulos, Leonardo Candela, Donatella Castelli, Perla Innocenti, Yannis Ioannidis, Akrivi Katifori, Anna Nika, Stephanie Parker, Seamus Ross, Costantino Thanos, Eleni Toli (+1 others)
2011 New Trends in Qualitative and Quantitative Methods in Libraries  
We demonstrate how standards can be used, profiled and enriched to pave the way to increased interoperability of EODC and can help delivering and leveraging the power of EO data building, efficient discovery  ...  The novelty of the approach results in different innovative solutions and the lack of commonly agreed definition of EODC.  ...  The views expressed in the paper are those of the authors and do not necessarily reflect the views of the institutions they belong to.  ... 
doi:10.1142/9789814350303_0042 fatcat:2rhc7i7vwzfq3bukjktvfdv37q

Paving the Way to Increased Interoperability of Earth Observations Data Cubes

Gregory Giuliani, Joan Masó, Paolo Mazzetti, Stefano Nativi, Alaitz Zabala
2019 Data  
We demonstrate how standards can be used, profiled and enriched to pave the way to increased interoperability of EODC and can help delivering and leveraging the power of EO data building, efficient discovery  ...  The novelty of the approach results in different innovative solutions and the lack of commonly agreed definition of EODC.  ...  The views expressed in the paper are those of the authors and do not necessarily reflect the views of the institutions they belong to.  ... 
doi:10.3390/data4030113 fatcat:aan3n5htczhp7iqhmp4zq6mde4

DW2RDF4SDG – Ontology modeling from multi-dimensional cubes for Sustainable Development Goals

Flavia Serra, Tatiana Delgado
2018 Sistemas y Telemática  
An ontology, in its basic expression as RDF, represents the reality from relationships between classes, and it is the base for linked data of the semantic Web.  ...  This work provides a basic methodology to obtain an ontology RDF from a multidimensional model of a data warehouse, capable to be aligned to other ontology of the Sustainable Developments Goals.  ...  The proposed methodology is aimed to transforming data models, from multi-dimensional cubes to RDF ontology schemes; that is, it remains in the TBox terminological dimension, and does not include in its  ... 
doi:10.18046/syt.v16i44.2724 fatcat:spzaz4hharbk5d5f4auo7hhnia

Semantic Web Mining. State of the Art and Future Directions

Gerd Stumme, Andreas Hotho, Bettina Berendt
2006 Social Science Research Network  
Given the primarily syntactical nature of the data being mined, the discovery of meaning is impossible based on these data only.  ...  This survey analyzes the convergence of trends from both areas: More and more researchers are working on improving the results of Web Mining by exploiting semantic structures in the Web, and they make  ...  Sesame [83] is an architecture for efficient storage and expressive querying of large quantities of RDF(S) data.  ... 
doi:10.2139/ssrn.3199332 fatcat:k4byg7k2efe3nla67b6f6ci22m

Conciliating Perspectives from Mapping Agencies and Web of Data on Successful European SDIs: Toward a European Geographic Knowledge Graph

Bucher, Tiainen, Brasch, Janssen, Kotzinos, Čeh, Rijsdijk, Folmer, Damme, Zhral
2020 ISPRS International Journal of Geo-Information  
It studies contributions and competences from two communities in this field: cartographers, authoritative data providers, and geographic information scientists on the one hand, and computer scientists  ...  Spatial Data Infrastructures (SDIs) are a key asset for Europe. This paper concentrates on unsolved issues in SDIs in Europe related to the management of semantic heterogeneities.  ...  Acknowledgments: The authors acknowledge the contribution of participants to EuroSDR and Eurogeographics seminars and workshops on INSPIRE or on Linked Data.  ... 
doi:10.3390/ijgi9020062 fatcat:mdfq6bzg6reihpsechcefzra6q

Data Sharing in P2P Systems [chapter]

Rabab Hayek, Guillaume Raschia, Patrick Valduriez, Noureddine Mouaddib
2009 Handbook of Peer-to-Peer Networking  
In this chapter, we survey P2P data sharing systems.  ...  Then, we discuss data indexing techniques based on their distribution degree and the semantics they can capture from the underlying data.  ...  Pre-computed aggregate values are stored in the cube cells and then, the OLAP system provides tools to navigate within these cells.  ... 
doi:10.1007/978-0-387-09751-0_19 fatcat:i5pyj3c53rc6lfdxiqnconhsiq

A Fast Flexible Docking Method using an Incremental Construction Algorithm

Matthias Rarey, Bernd Kramer, Thomas Lengauer, Gerhard Klebe
1996 Journal of Molecular Biology  
The incremental construction algorithm is based on a greedy strategy combined with efficient methods for overlap detection and for the search of new interactions.  ...  It combines an appropriate model of the physico-chemical Technology (GMD), Institute for Algorithms and Scientific properties of the docked molecules with efficient methods for sampling the conformational  ...  Acknowledgements This work was performed as part of the RELIWE-Project, which is partially funded by the German  ... 
doi:10.1006/jmbi.1996.0477 pmid:8780787 fatcat:ro6hbv757zejbnkcknsaastpzm

Managing, querying and analyzing big data on the web [article]

Μάριος Μεϊμάρης, University Of Thessaly, Ιωάννης Αναγνωστόπουλος
To this end, we focus in three directions, namely (i) RDF data evolution, (ii) storage, indexing and query optimization in RDF/SPARQL engines, and (iii) efficient and scalable information retrieval from  ...  In the first direction (chapters 2 and 3), we study the problem of representing, storing and querying evolving RDF data.  ...  Panos Vassiliadis for his mentoring and guidance. Finally, I would like to thank all of my co-authors and colleagues.  ... 
doi:10.26253/heal.uth.8604 fatcat:r3ix6dmygnehjngen3p4xe3vde

Multiple subtropical stratospheric intrusions over Reunion Island: Observational, Lagrangian, and Eulerian numerical modeling approaches

H. Vérèmes, J.-P. Cammas, J.-L. Baray, P. Keckhut, C. Barthe, F. Posny, P. Tulet, D. Dionisi, S. Bielli
2016 Journal of Geophysical Research - Atmospheres  
A singular structure of the ozone vertical profile with three peaks (in excess of 90 ppbv, at~8,~10, and~13 km altitude) embedded in a thick dry layer of air suggested stratospheric intrusions with multiple  ...  and to describe the detailed potential vorticity and ozone structures in which are embedded in the observed multiple stratospheric intrusions.  ...  The reliability of measurements and the complementarity and/or limits of the different methodological approaches are also discussed. Finally, conclusion is set in section 4.  ... 
doi:10.1002/2016jd025330 fatcat:enalxnkc7zfg7cyc2sbmumul7u

An AI framework and a metamodel for collaborative situations: Application to crisis management contexts

Frederick Benaben, Audrey Fertier, Aurélie Montarnal, Wenxin Mu, Zheng Jiang, Sebastien Truptil, Anne‐Marie Barthe‐Delanoë, Matthieu Lauras, Guillaume Mace‐Ramete, Tiexin Wang, Loïc Bidoux, Jacques Lamothe
2020 Journal of Contingencies and Crisis Management  
framework and a metamodel for collaborative situations: Application to crisis management contexts.  ...  In 2015, the technology of big data and cloud computing are well developed.  ...  | Limits and complementarities of both visions In the context of this article, the question of Veracity of data is out of scope due to the fact that we only consider data that is already clean and trustable  ... 
doi:10.1111/1468-5973.12310 fatcat:y4jnaypo3bhvvndrmyprs5xdju

Convergence of Recognition, Mining, and Synthesis Workloads and Its Implications

Yen-Kuang Chen, J. Chhugani, P. Dubey, C.J. Hughes, Daehyun Kim, S. Kumar, V.W. Lee, A.D. Nguyen, M. Smelyanskiy
2008 Proceedings of the IEEE  
This processing is further decomposed in terms of an integration of three fundamental compute capabilitiesVrecognition, mining, and synthesis (RMS).  ...  The set of RMS workloads is examined next in terms of usage, mathematical models, numerical algorithms, and underlying data structures.  ...  This allows a reduction in the number of interactions between a user and his/her computer, and therefore an increase in the system's efficiency.  ... 
doi:10.1109/jproc.2008.917729 fatcat:p3khrvcmb5em7fbjlf3vhostlq

Expanding Lorentz and spectrum corrections to large volumes of reciprocal space for single-crystal time-of-flight neutron diffraction

Tara M. Michels-Clark, Andrei T. Savici, Vickie E. Lynch, Xiaoping Wang, Christina M. Hoffmann
2016 Journal of Applied Crystallography  
In this contribution, a comprehensive data analysis approach is introduced to correct and merge the full volume of scattering data in a single step, while correctly accounting for the statistical weight  ...  In contrast, mDS is weak and covers expansive volumes of reciprocal space close to, or between, Bragg reflections.  ...  X-ray data were collected by Dr R. Custelcean at Chemical Sciences Division, Oak Ridge National Laboratory.  ... 
doi:10.1107/s1600576716001369 pmid:27047306 pmcid:PMC4815874 fatcat:s6pydsnt5vhe5grd64fafd65iy
« Previous Showing results 1 — 15 out of 41 results