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Column-Oriented Datalog Materialization for Large Knowledge Graphs

Jacopo Urbani, Ceriel Jacobs, Markus Krötzsch
In this paper, we present a new method of materializing Datalog inferences, which combines a column-based memory layout with novel optimization methods that avoid redundant inferences at runtime.  ...  Our empirical evaluation shows that this approach can often match or even surpass the performance of state-of-the-art systems, especially under restricted resources.  ...  Second, our implementation does not currently exploit multiple processors, and it will be interesting to see to how techniques of intra/inter query parallelism can be applied in this setting.  ... 
doi:10.1609/aaai.v30i1.9993 fatcat:gzpkfwgwazdhdaldvcssdgaova

Incrementally Maintaining Materializations of Ontologies Stored in Logic Databases [chapter]

Raphael Volz, Steffen Staab, Boris Motik
2005 Lecture Notes in Computer Science  
This article presents a technique to incrementally maintain materializations of ontological entailments.  ...  Materialization consists in precomputing and storing a set of implicit entailments, such that frequent and/or crucial queries to the ontology can be solved more efficiently.  ...  However, as the computation of the materialization is often complex and time consuming, it is desirable to apply more efficient techniques in practice, i.e. to incrementally maintain a materialization.  ... 
doi:10.1007/978-3-540-30567-5_1 fatcat:ocy7flfibndapbkge6u6wy67xi

Data‐Driven Materials Science: Status, Challenges, and Perspectives

Lauri Himanen, Amber Geurts, Adam Stuart Foster, Patrick Rinke
2019 Advanced Science  
In this perspective article, the historical development and current state of data-driven materials science, building from the early evolution of open science to the rapid expansion of materials data infrastructures  ...  However, there are a variety of challenges that impede progress in data-driven materials science: data veracity, integration of experimental and computational data, data longevity, standardization, and  ...  Rousi, Milica Todorovic ′, Sven Bossuyt, Miguel Caro, David Gao, Matthias Scheffler, Bryce Meredig, and Heidi Henrickson for insightful discussions and a careful reading of our manuscript. Computing  ... 
doi:10.1002/advs.201900808 pmid:31728276 pmcid:PMC6839624 fatcat:j6adrk22zfadrm4usoelg3c7p4

SPARQL Update for Materialized Triple Stores under DL-Lite_RDFS Entailment

Albin Ahmeti, Diego Calvanese, Axel Polleres
2014 International Workshop on Description Logics  
We define a fragment of SPARQL basic graph patterns corresponding to (the RDFS fragment of) DL-Lite and the corresponding SPARQL update language, dealing with updates both of ABox and of TBox statements  ...  However, computing answers entailed by ontologies in triple stores is usually treated orthogonally to updates.  ...  This work has been funded by the Vienna Science and Technology Fund (WWTF, project ICT12-015), by the Vienna PhD School of Informatics, and by EU Project Optique (grant n. FP7-318338).  ... 
dblp:conf/dlog/AhmetiCP14 fatcat:33try6e74vdp5khxrqjtsigppq

Column-Oriented Datalog Materialization for Large Knowledge Graphs (Extended Technical Report) [article]

Jacopo Urbani, Ceriel Jacobs, Markus Krötzsch
2016 arXiv   pre-print
In this paper, we present a new method of materializing Datalog inferences, which combines a column-based memory layout with novel optimization methods that avoid redundant inferences at runtime.  ...  Our empirical evaluation shows that this approach can often match or even surpass the performance of state-of-the-art systems, especially under restricted resources.  ...  Acknowledgments This work was partially funded by COMMIT, the NWO VENI project 639.021.335, and the DFG in Emmy Noether grant KR 4381/1-1 and in CRC 912 HAEC within the cfAED Cluster of Excellence.  ... 
arXiv:1511.08915v2 fatcat:fnoxuh73lfabng676hdhjvbfja

Intelligent Model for Predicting the Quality of Services Violation

Muhammad Adnan Khan, Asma Kanwal, Sagheer Abbas, Faheem Khan, T. Whangbo
2022 Computers Materials & Continua  
technique in comparison of conventional PSO technique.  ...  This paper also compares Simple-PSO and Parallel Mutant-PSO.  ...  Conflicts of Interest: The authors declare that they have no conflicts of interest to report regarding the present study.  ... 
doi:10.32604/cmc.2022.023480 fatcat:f7tfg52q6zashdzbree5jkfhhu

Models and simulations in material science: two cases without error bars

Sylvia Wenmackers, Danny E. P. Vanpoucke
2012 Statistica neerlandica (Print)  
DNA molecules on diamond and a scanning tunneling microscopy study of platinum-induced nanowires on germanium.  ...  We discuss two research projects in material science in which the results cannot be stated with an estimation of the error: a spectro- scopic ellipsometry study aimed at determining the orientation of  ...  the practice of modeling.  ... 
doi:10.1111/j.1467-9574.2011.00519.x fatcat:pfbl4belhvfxfb2i2durbjfguy

A survey of large-scale reasoning on the Web of data

Grigoris Antoniou, Sotiris Batsakis, Raghava Mutharaju, Jeff Z. Pan, Guilin Qi, Ilias Tachmazidis, Jacopo Urbani, Zhangquan Zhou
2018 Knowledge engineering review (Print)  
This is particularly true for the so-called Web of Data, in which data is semantically enriched and interlinked using ontologies.  ...  In this large and uncoordinated environment, reasoning can be used to check the consistency of the data and of associated ontologies, or to infer logical consequences which, in turn, can be used to obtain  ...  "III: Small: TROn -Tractable Reasoning with Ontologies."  ... 
doi:10.1017/s0269888918000255 fatcat:bergc5uphbceznigppektgvzrm

Reasoning at Scale [chapter]

Jacopo Urbani
2018 Encyclopedia of Big Data Technologies  
that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study  ...  General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications  ...  Three different types of parallelism can be applied to the rule execution: Intra-rule parallelism, inter-rule parallelism, and instance-based parallelism.  ... 
doi:10.1007/978-3-319-63962-8_317-1 fatcat:stdvujfh2rgrbakf44lfi5uway

Real-World Reasoning with OWL [chapter]

Timo Weithöner, Thorsten Liebig, Marko Luther, Sebastian Böhm, Friedrich von Henke, Olaf Noppens
2007 Lecture Notes in Computer Science  
This work is motivated by experiences in the course of developing an ontology-based application within a real-world setting.  ...  assertional data, and frequent updates in a sound and complete way.  ...  A more fine-grained map of the border of effectively tractable ontologies still needs to be practically explored in order to be helpful for developers.  ... 
doi:10.1007/978-3-540-72667-8_22 fatcat:ksxcynqhgnfgvccphvxecqaw34

The Benefits of Incremental Reasoning in OWL EL

Yevgeny Kazakov, Pavel Klinov
2013 International Semantic Web Conference  
experience of a user editing a large ontology can be improved if the reasoner (or ontology IDE) provides the capability of instantaneously re-classifying the ontology in the background mode when a change  ...  In addition, we intend to demonstrate how incremental reasoning helps in other tasks such as answering DL queries and computing explanations of entailments.  ...  Introduction The EL family of Description Logics (DLs) are tractable extensions of the DL EL featuring conjunction and existential restriction.  ... 
dblp:conf/semweb/KazakovK13 fatcat:nym7xub2orb4lmijxhhhijls7m

Community-Driven Approach to Large-Scaled Ontology Development based on OAM Framework: a Case Study on Life Cycle Assessment

Akkharawoot Takhom, Prachya Boonkwan, Mitsuru Ikeda, Boontawee Suntisrivaraporn, Thepchai Supnithi
2014 Joint International Conference of Semantic Technology  
system, on top of the existing Ontology-based Application Management Framework (OAM) [1] .  ...  When applying the design to the task of Life Cycle Assessment, we discover additional needs to partition a large ontology to modularize the users' responsibilities and to provide thread-based conversation  ...  Materials and information provided by National Metal and Materials Technology Center (MTEC, Life Cycle Assessment Laboratory, Thailand).  ... 
dblp:conf/jist/TakhomBISS14 fatcat:njrf3p2t2fa2fpxkiqe6rngihi

A superficial reading of Henry James: preoccupations with the material world

2007 ChoiceReviews  
Their praise and criticism have made this project much stronger than it would otherwise be.  ...  I also want to acknowledge a number of other people who have also contributed much to my intellectual life over the years I worked on this project:  ...  "warming" are in parallel position and parallel form, the object that follows should be governed by each.  ... 
doi:10.5860/choice.44-3167 fatcat:nobpudgsyfb75dbpvg5bmkfvci

Editorial: Ontology Challenges: A Thumbnail Historical Perspective

James Geller, Yehoshua Perl, Jintae Lee
2004 Knowledge and Information Systems  
Their survey includes both techniques for building ontologies from scratch and for building ontologies from smaller components.  ...  With the partial failure of the CYC project (defined by not reaching some of the very well-defined and published goals of CYC's own designers), the early 1990s appeared to be the time when practical knowledge  ... 
doi:10.1007/s10115-003-0134-5 fatcat:nv6cturbjvd6dmpikbunqnvcdy

Distributed Biomedical Terminology Development: From Experiments to Open Process

C. G. Chute
2010 IMIA Yearbook of Medical Informatics  
Objective: Can social computing efforts materially alter the distributed creation and maintenance of complex biomedical terminologies and ontologies; a review of distributed authoring history and status  ...  practices.  ...  Chute Chairs the ICD-11 Revision Steering Committee, and is grateful for the input and advise of the World Health Organization.  ... 
doi:10.1055/s-0038-1638690 fatcat:q6ngwv23avdslehajt2vnvefyq
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