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Space-efficient, Fast and Exact Routing in Time-dependent Road Networks [article]

Ben Strasser, Dorothea Wagner, Tim Zeitz
2019 arXiv   pre-print
Existing techniques follow a two phase approach: In an offline, preprocessing step, a database index is built. The index only depends on the road network and the traffic patterns.  ...  We study the problem of computing shortest paths in massive road networks with traffic predictions.  ...  ACKNOWLEDGMENTS We thank Lars GottesbÃijren and Michael Haman for fruitful discussions and feedback. We also thank Marcel Radermacher for his input on approximation algorithms.  ... 
arXiv:1910.12726v1 fatcat:4egyxwcmhvflretcyq4sgu3aau

Space-Efficient, Fast and Exact Routing in Time-Dependent Road Networks

Ben Strasser, Dorothea Wagner, Tim Zeitz
2021 Algorithms  
The index depends on the road network and the traffic patterns but not on the path start and end. The latter are the input of the query phase, in which shortest paths are computed.  ...  We study the problem of quickly computing point-to-point shortest paths in massive road networks with traffic predictions.  ...  Acknowledgments: We thank Lars Gottesbüren and Michael Hamann for fruitful discussions and feedback. We also thank Marcel Radermacher for his input on approximation algorithms.  ... 
doi:10.3390/a14030090 fatcat:xkwbq3wf3zbv5dpralmwh25hse

Space-efficient, fast and exact routing in time-dependent road networks

Ben Strasser, Dorothea Wagner, Tim Zeitz
2020
The index depends on the road network and the traffic patterns but not on the path start and end. The latter are the input of the query phase, in which shortest paths are computed.  ...  We study the problem of computing shortest paths in massive road networks with traffic predictions.  ...  We conclude in Section 5. 81:4 Space-Efficient, Fast and Exact Routing in Time-Dependent Road Networks 2 Preliminaries We model road networks as directed graphs G = (V, A).  ... 
doi:10.5445/ir/1000125767 fatcat:mglr2ayb7bgg3nmczu3xbspj4a

Engineering Route Planning Algorithms [chapter]

Daniel Delling, Peter Sanders, Dominik Schultes, Dorothea Wagner
2009 Lecture Notes in Computer Science  
In particular, for large road networks it would be prohibitive to precompute and store shortest paths between all pairs of nodes.  ...  Obviously, there is some tradeoff between query time, preprocessing time, and space for preprocessed information.  ...  Acknowledgements We would like to thank our coauthors on route planning, Holger Bast  ... 
doi:10.1007/978-3-642-02094-0_7 fatcat:7ythem6y3nhjlasccedzupksui

Time Dependent Contraction Hierarchies -- Basic Algorithmic Ideas [article]

Peter Sanders
2008 arXiv   pre-print
Contraction hierarchies are a simple hierarchical routing technique that has proved extremely efficient for static road networks.  ...  We explain how to generalize them to networks with time-dependent edge weights. This is the first hierarchical speedup technique for time-dependent routing that allows bidirectional query algorithms.  ...  Like many of the most successful speedup techniques for routing in road networks, the CH query-algorithm uses bidirectional search.  ... 
arXiv:0804.3947v1 fatcat:pkipeihnnjdg3aakvwkiu73kv4

A Cloud-Based Time-Dependent Routing Service [chapter]

Kalliopi Giannakopoulou, Spyros Kontogiannis, Georgia Papastavrou, Christos Zaroliagis
2017 Lecture Notes in Computer Science  
Our cloud-based time-dependent routing service exhibits an excellent practical behavior on a diversity (w.r.t. to scale and type) of real-world road networks.  ...  We present a cloud-based time-dependent routing service, which is a core component in providing efficient personalized renewable mobility services in smart cities.  ...  Another axis of complexity, for providing route plans in time-dependent road networks, is the fact that the historic traffic data and, most importantly, the traffic metadata which are created by the routing  ... 
doi:10.1007/978-3-319-57045-7_4 fatcat:c7ivbd3akraerizteih5nfi3x4

Time-Dependent Contraction Hierarchies [chapter]

G. Veit Batz, Daniel Delling, Peter Sanders, Christian Vetter
2009 2009 Proceedings of the Eleventh Workshop on Algorithm Engineering and Experiments (ALENEX)  
Contraction hierarchies are a simple hierarchical routing technique that has proved extremely efficient for static road networks.  ...  We explain how to generalize them to networks with time-dependent edge weights. This is the first hierarchical speedup technique for timedependent routing that allows bidirectional query algorithms.  ...  We also thank Giacomo Nannicini for providing us with his time-dependent edge-cost generator.  ... 
doi:10.1137/1.9781611972894.10 dblp:conf/alenex/BatzDSV09 fatcat:cs2vs6vupba5hirb47rz5lg4qq

Route Planning in Transportation Networks [chapter]

Hannah Bast, Daniel Delling, Andrew Goldberg, Matthias Müller-Hannemann, Thomas Pajor, Peter Sanders, Dorothea Wagner, Renato F. Werneck
2016 Lecture Notes in Computer Science  
We survey recent advances in algorithms for route planning in transportation networks.  ...  A variety of techniques provide different trade-offs between preprocessing effort, space requirements, and query time.  ...  Time-Dependence. In real transportation networks, the best route often depends on the departure time in a predictable way [102] .  ... 
doi:10.1007/978-3-319-49487-6_2 fatcat:zbg272ftdfempady3cjynh6q4e

Route Planning in Transportation Networks [article]

Hannah Bast, Daniel Delling, Andrew Goldberg, Matthias Müller-Hannemann, Thomas Pajor, Peter Sanders, Dorothea Wagner, Renato F. Werneck
2015 arXiv   pre-print
We survey recent advances in algorithms for route planning in transportation networks.  ...  A variety of techniques provide different trade-offs between preprocessing effort, space requirements, and query time.  ...  Time-Dependence In real transportation networks, the best route often depends on the departure time in a predictable way [102] .  ... 
arXiv:1504.05140v1 fatcat:ox42rhvuynd5loq6dljhnfecvu

Towards Fast and Accurate Solutions to Vehicle Routing in a Large-Scale and Dynamic Environment [chapter]

Yaguang Li, Dingxiong Deng, Ugur Demiryurek, Cyrus Shahabi, Siva Ravada
2015 Lecture Notes in Computer Science  
In this paper, we study the Time-Dependent Vehicle Routing Problem (TDVRP) that enables both efficient and accurate solutions for large number of delivery locations on real world road network.  ...  Our experiments with real road networks and real traffic data and delivery locations show that our algorithm can solve a TD-VRP instance with 1000 delivery locations within 20 minutes, which is 8 times  ...  This research has been funded in part by NSF grants IIS-1115153 and IIS-1320149, the USC Integrated Media Systems Center (IMSC), METRANS Transportation Center under grants from Caltrans, and unrestricted  ... 
doi:10.1007/978-3-319-22363-6_7 fatcat:gw5tsht54nbebcgfrm32dkwn5u

Knowledge-Based Spatial Reasoning for IoT-Enabled Smart City Applications

Ralf Toenjes, Daniel Kuemper, Marten Fischer
2015 2015 IEEE International Conference on Data Science and Data Intensive Systems  
For efficient analysis of large smart city data sets in (real) time a knowledge-based approach is suggested, constraining iteratively the search space while increasing accuracy by more complex computation  ...  Results are shown for searching the distance to the nearest object, e.g., parking space.  ...  While temperature will be similar in the neighbourhood, noise propagation will depend on shielding buildings and traffic flows on road networks, ongoing construction work, traffic density etc..  ... 
doi:10.1109/dsdis.2015.53 dblp:conf/dsdis/ToenjesKF15 fatcat:evmodkhh2vdjtj64yccjti22ce

An Efficient Traffic Analysis and Optimization on the Dynamic Network Using Two Stage Routing Algorithm

A. Keerthika, K. Poonkavithai
2015 International Journal of Future Generation Communication and Networking  
This paper address these limitation, proposes two stage routing algorithm and weight propagation model to predict the cost of an arbitrary path on road network and accurately detects the traffic environment  ...  However, such weights are not readily available on the road network. So, randomly assign the weights for each road segments and it typically lack the speed pattern of the road network.  ...  in proposed time dependent fast route algorithm.  ... 
doi:10.14257/ijfgcn.2015.8.1.27 fatcat:s6ug5ahqpbh7fpu4cqlk42osqu

A Fast and Tight Heuristic for A* in Road Networks [article]

Ben Strasser, Tim Zeitz
2021 arXiv   pre-print
We study exact, efficient and practical algorithms for route planning in large road networks.  ...  On road networks, shortest paths can also be quickly computed using hierarchical speedup techniques. They achieve speed and exactness but sacrifice A*'s flexibility.  ...  Conclusion In this paper, we introduced CH-Potentials, a fast, exact, and flexible two-phase algorithm based on A* and CH for finding shortest paths in road networks.  ... 
arXiv:1910.12526v2 fatcat:tebqan2vvrfxlnxfq64qauwtxy

A correlation-aware partial materialization scheme for near real-time automotive queries

Yu Hua, Dan Feng
2014 2014 International Conference on Smart Computing  
The partial materialization usually satisfies realtime and space requirements in VANETs.  ...  In order to improve query accuracy and provide quick query response, we propose a novel scheme for real-time aggregate queries, called Road Cube, which essentially makes use of precomputation on interested  ...  Average route lengths are 157913 and 5572 respectively in San Joaquin and City of Oldenburg road networks.  ... 
doi:10.1109/smartcomp.2014.7043864 dblp:conf/smartcomp/HuaF14 fatcat:sozrrgspvbbzpmvtsd52zmtpcy

A Communications-Oriented Perspective on Traffic Management Systems for Smart Cities: Challenges and Innovative Approaches

Soufiene Djahel, Ronan Doolan, Gabriel-Miro Muntean, John Murphy
2015 IEEE Communications Surveys and Tutorials  
road Traffic Management Systems (TMS) more efficient to cope with the above issues in future smart cities.  ...  In this survey, we present an up to date review of the different technologies used in the different phases involved in a TMS, and discuss the potential use of smart cars and social media to enable fast  ...  travel time from one location to another in the road network.  ... 
doi:10.1109/comst.2014.2339817 fatcat:ap7hvhawqrf7zb5noxm4ph5orq
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