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Engineering Oracles for Time-Dependent Road Networks [article]

Spyros Kontogiannis and George Michalopoulos and Georgia Papastavrou and Andreas Paraskevopoulos and Dorothea Wagner and Christos Zaroliagis
2015 arXiv   pre-print
We implement and experimentally evaluate landmark-based oracles for min-cost paths in large-scale time-dependent road networks.  ...  We significantly improve the FLAT oracle, improving the previous query time by 30% and doubling the Dijkstra-rank speedup.  ...  Conclusions and Future Work We provided an extensive experimental evaluation of landmark-based oracles for time-dependent road networks.  ... 
arXiv:1511.08303v1 fatcat:y3ye3f4ua5d43cwp5sz2uv66za

Exploiting Amorphous Data Parallelism to Speed-Up Massive Time-Dependent Shortest-Path Computations

Spyros Kontogiannis, Anastasios Papadopoulos, Andreas Paraskevopoulos, Christos Zaroliagis, Michael Wagner
2019 Algorithmic Approaches for Transportation Modeling, Optimization, and Systems  
as a subroutine in the daily maintenance of large-scale time-dependent graphs representing real-world relationships or technological networks: the many-to-all time-dependent shortest paths (MATDSP) problem  ...  Our experimental evaluations, both on real-world and on synthetic benchmark instances of timedependent road networks, provide insight how one should organize heavy MATDSP computations, depending on the  ...  Our motivation comes from the need for fast MATDSP computations when dealing with travel-time, landmark-based, oracles for large-scale road networks with time-dependent arc-traversal-time functions.  ... 
doi:10.4230/oasics.atmos.2019.9 dblp:conf/atmos/KontogiannisPPZ19 fatcat:tl44pvqowbaejhmoyfxyxclq5i

Analysis and Experimental Evaluation of Time-Dependent Distance Oracles [chapter]

Spyros Kontogiannis, George Michalopoulos, Georgia Papastavrou, Andreas Paraskevopoulos, Dorothea Wagner, Christos Zaroliagis
2014 2015 Proceedings of the Seventeenth Workshop on Algorithm Engineering and Experiments (ALENEX)  
Urban road networks are represented as directed graphs, accompanied by a metric which assigns cost functions (rather than scalars) to the arcs, e.g. representing time-dependent arc-traversal-times.  ...  In this work, we present oracles for providing time-dependent min-cost route plans, and conduct their experimental evaluation on a real-world data set (city of Berlin).  ...  Conclusions and Future Work In this work we have proposed novel distance oracles for sparse time dependent network instances corresponding mainly to road networks, which achieve sublinear average query  ... 
doi:10.1137/1.9781611973754.13 dblp:conf/alenex/KontogiannisMPPWZ15 fatcat:fw63juzbqvgpdohr6zu3x5onji

Distance Oracles for Spatial Networks

Jagan Sankaranarayanan, Hanan Samet
2009 Proceedings / International Conference on Data Engineering  
An approximate distance oracle is proposed for spatial networks that exploits the coherence between the spatial position of vertices and the network distance between them.  ...  Experimental results indicate that the proposed technique is scalable and can be applied to sufficiently large road networks.  ...  For example, a distance oracle for the road network of USA can be precomputed and commercially distributed.  ... 
doi:10.1109/icde.2009.53 dblp:conf/icde/SankaranarayananS09 fatcat:ivqlncyve5glfhucnr6rg2fksq

Improved Oracles for Time-Dependent Road Networks

Spyros Kontogiannis, Georgia Papastavrou, Andreas Paraskevopoulos, Dorothea Wagner, Christos Zaroliagis, Marc Herbstritt
2017 Algorithmic Approaches for Transportation Modeling, Optimization, and Systems  
A novel landmark-based oracle (CFLAT) is presented, which provides earliest-arrival-time route plans in time-dependent road networks.  ...  It also achieves competitive query-time performance compared to state-of-art speedup heuristics for time-dependent road networks, whose query-times in most cases do not account for path construction.  ...  Veit Batz, Julian Dibbelt and Ben Strasser for valuable and fruitful discussions.  ... 
doi:10.4230/oasics.atmos.2017.4 dblp:conf/atmos/KontogiannisPPW17 fatcat:vr4ztheutreejl3i3qecqvhbyy

Spatial Query Localization Method In Limited Reference Point Environment

Victor Krebss
2013 Zenodo  
New opportunities arise for the localization due to the rapidly emerging concept of a wireless ad-hoc network.  ...  In this paper, we propose localization approach based on the graph mapped distances on the digital road map data basis.  ...  the road network.  ... 
doi:10.5281/zenodo.1074278 fatcat:cunbivwsu5ffvggicsso2uyt5u

A Spatial Data Model for Moving Object Databases [article]

Hadi Hajari, Farshad Hakimpour
2014 arXiv   pre-print
Moreover, concerning real world applications, moving objects move along constrained environments like transportation networks so that an extra algebra for modeling networks is demanded, too.  ...  Finally as a proof of concept, we implement a generator to generate data for moving objects constrained by a transportation network. Such a generator primarily aims at traffic planning applications.  ...  Transportation road networks are good instances of the second type of the Oracle network data model.  ... 
arXiv:1403.3304v1 fatcat:ls5gdqi2lvhwrj6dqddpurzige

A Spatial Data Model for Moving Object Databases

Hadi Hajari, Farshad Hakimpour
2014 International Journal of Database Management Systems  
Moreover, concerning real world applications, moving objects move along constrained environments like transportation networks so that an extra algebra for modeling networks is demanded, too.  ...  This implementation demonstrates the capabilities of the models not only for modeling transportation networks but also for representing and querying moving objects.  ...  Transportation road networks are good instances of the second type of the Oracle network data model.  ... 
doi:10.5121/ijdms.2014.6101 fatcat:mzwol55tvzeupivcxoxk3unwei

A Spatial Data Model for Moving Object Databases

Hadi Hajari, Farshad Hakimpour
2014 International Journal of Database Management Systems  
Moreover, concerning real world applications, moving objects move along constrained environments like transportation networks so that an extra algebra for modeling networks is demanded, too.  ...  This implementation demonstrates the capabilities of the models not only for modeling transportation networks but also for representing and querying moving objects.  ...  Transportation road networks are good instances of the second type of the Oracle network data model.  ... 
doi:10.5121/ijdms.2013.6101 fatcat:c5mhz3vlaraj5kbowqhpzjguga

Navigation made personal

Daniel Delling, Andrew V. Goldberg, Moises Goldszmidt, John Krumm, Kunal Talwar, Renato F. Werneck
2015 Proceedings of the 23rd SIGSPATIAL International Conference on Advances in Geographic Information Systems - GIS '15  
Our approach learns cost functions using coordinate descent, leveraging a state-of-the-art route planning engine for efficiency.  ...  Oracle Approximation The quality oracle described so far is fast enough to handle a large number of traces on continental-sized road networks, but we can improve efficiency further.  ...  The time to incorporate a new cost function depends linearly on graph size, which makes it much faster on smaller networks, such as metropolitan areas.  ... 
doi:10.1145/2820783.2820808 dblp:conf/gis/DellingGGKTW15 fatcat:gnxz3y3wynezteczfs645spb6m

Query Processing Using Distance Oracles for Spatial Networks

Jagan Sankaranarayanan, Hanan Samet
2010 IEEE Transactions on Knowledge and Data Engineering  
Experimental results indicate that the proposed technique is scalable and can be applied to sufficiently large road networks.  ...  For example, a 10-percentapproximate oracle (" ¼ 0:1) on a large network yielded an average error of 0.9 percent with 90 percent of the answers having an error of 2 percent or less and an average retrieval  ...  Walton Visitor Award of the Science Foundation of Ireland, and the National Center for Geocomputation at the National University of Ireland at Maynooth.  ... 
doi:10.1109/tkde.2010.75 fatcat:cdmtftqhxnbarpb7wof7jz7cay

HLDB

Ittai Abraham, Daniel Delling, Amos Fiat, Andrew V. Goldberg, Renato F. Werneck
2012 Proceedings of the 20th International Conference on Advances in Geographic Information Systems - SIGSPATIAL '12  
HLDB is based on hub labels (HL), the fastest point-to-point algorithm for road networks, and its queries are implemented (quite naturally) in standard SQL.  ...  Within the database, HLDB answers exact distance queries and retrieves full shortest-path descriptions in real time, even on networks with tens of millions of vertices.  ...  Moreover, HLDB queries are very efficient, since they are based on HL, the fastest known external distance oracle algorithm for road networks.  ... 
doi:10.1145/2424321.2424365 dblp:conf/gis/AbrahamDFGW12 fatcat:nmtvvbxrg5b4fov4bwvh4uschm

COPERNICUS: Context-Preserving Engine for Route Navigation with Interactive User-modifiable Scaling

Hartmut Ziegler, Daniel A. Keim
2008 Computer graphics forum (Print)  
In this paper, we present an automated system for generating context-preserving route maps that depict navigation routes as a path between nodes and edges inside a topographic network.  ...  engine.  ...  Acknowledgements: The authors thank Navteq for the geographic data, Holger Bruch (Logiball) for the GDF Suite Software, and Chuck Freiwald and Siva Rivada (Oracle) for their help with the Oracle routing  ... 
doi:10.1111/j.1467-8659.2008.01226.x fatcat:aw2f3fg5m5fbxi4wfuyyjisroi

An I/O-efficient Distance Oracle for Evolving Real-World Graphs [chapter]

Deepak Ajwani, Ulrich Meyer, David Veith
2014 2015 Proceedings of the Seventeenth Workshop on Algorithm Engineering and Experiments (ALENEX)  
In this paper, we focus on engineering an I/O-efficient distance oracle for large graphs that model real-world interactions.  ...  Our engineered oracle (i) preprocesses graphs with multi-billion edges in less than an hour using a single core of a typical PC, (ii) answers online shortest path queries in milliseconds using a SSD, (  ...  Acknowledgments We want to thank Daniel Delling, Renato Werneck, Thomas Pajor, Xiaokui Xiao and Zhu DiWen for providing the results respectively source code from their distance oracles for comparison.  ... 
doi:10.1137/1.9781611973754.14 dblp:conf/alenex/AjwaniMV15 fatcat:ydy7dz3jjjer3lqujwgui27bqy

Improved Oracles for Time-Dependent Road Networks [article]

Spyros Kontogiannis and Georgia Papastavrou and Andreas Paraskevopoulos and Dorothea Wagner and Christos Zaroliagis
2017 arXiv   pre-print
A novel landmark-based oracle (CFLAT) is presented, which provides earliest-arrival-time route plans in time-dependent road networks.  ...  It also achieves competitive query-time performance and approximation guarantees compared to state-of-art speedup heuristics for time-dependent road networks, whose query-times in most cases do not account  ...  Veit Batz, Julian Dibbelt and Ben Strasser for valuable and fruitful discussions.  ... 
arXiv:1704.08445v1 fatcat:teh3h3dxofbynk2zacpzsx7u4e
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