Publications

2024

  • et al., Function and form of US cities, ArXiv Preprint ArXiv:2406.04543.
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  • et al., In silico human mobility data science: Leveraging massive simulated mobility data (vision paper), ACM Transactions on Spatial Algorithms and Systems 10, 1–27.
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  • , , & , Trajectory anomaly detection with language models, in Proceedings of the 32nd ACM International Conference on Advances in Geographic Information Systems .
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  • , , & , Urban mobility assessment using LLMs, in Proceedings of the 32nd ACM International Conference on Advances in Geographic Information Systems .
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2023

  • , , & , Are large language models geospatially knowledgeable?, in Proceedings of the 31st ACM International Conference on Advances in Geographic Information Systems, 1-4 .
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  • , , & , Automated framework for evaluating sustainability and resilience in higher education curriculum, in International Conference on Sustainable Built Environment, 3-16 (Springer Nature Singapore Singapore).
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  • et al., GeoAI for public health, Handbook of Geospatial Artificial Intelligence, 305.
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  • et al., Improving mobile positioning accuracy within an image-based hybrid geocrowdsourcing system, Abstracts of the ICA 6, 89.
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  • et al., Massive trajectory data based on patterns of life, in Proceedings of the 31st ACM International Conference on Advances in Geographic Information Systems, 1-4 .
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  • et al., The partition bridge (PB) tree: Efficient nearest neighbor query processing on road networks, Information Systems 118, 102256.
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  • et al., Urban life: A model of people and places, Computational and Mathematical Organization Theory 29, 20–51.
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2022

  • , , & , Factorized deep generative models for end-to-end trajectory generation with spatiotemporal validity constraints, in Proceedings of the 30th International Conference on Advances in Geographic Information Systems, 1-12 .
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  • et al., Predicting building types using OpenStreetMap, Scientific Reports 12, 19976.
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2021

  • et al., A hierarchical spatial network index for arbitrarily distributed spatial objects, ISPRS International Journal of Geo-Information 10, 814.
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  • et al., Disentangled dynamic graph deep generation, in Proceedings of the 2021 SIAM International Conference on Data Mining (SDM), 738-746 (Society for Industrial; Applied Mathematics).
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  • et al., Influence of geographic distance on CNN generalization for satellite image classification, in 2021 IEEE International Geoscience and Remote Sensing Symposium IGARSS, 4976-4979 (IEEE).
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  • , , & , Mining high resolution earth observation data cubes, in 17th International Symposium on Spatial and Temporal Databases, 152-156 .
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  • , , & , Movement-aware map construction, International Journal of Geographical Information Science 35, 1065–1093.
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  • et al., TG-GAN: Continuous-time temporal graph deep generative models with time-validity constraints, in Proceedings of the Web Conference 2021, 2104-2116 .
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  • et al., Urban life: A model of people and places, Computational and Mathematical Organization Theory, 1–32.
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2020

  • et al., Location-based social network data generation based on patterns of life, in Proceedings of the 21st IEEE International Conference on Mobile Data Management (MDM), to appear .
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  • et al., Location-based social simulation for prescriptive analytics of disease spread, SIGSPATIAL Special 12, 53–61.
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  • et al., Managing uncertainty in evolving geo-spatial data, in 2020 21st IEEE International Conference on Mobile Data Management (MDM), 5-8 (IEEE).
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  • , , & , Station-to-user transfer learning: Towards explainable user clustering through latent trip signatures using tidal-regularized non-negative matrix factorization, in Proceedings of the 28th International Conference on Advances in Geographic Information Systems, 303-313 .
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  • et al., Taking the pulse of COVID-19: A spatiotemporal perspective, International Journal of Digital Earth 13, 1186–1211.
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  • , , & , Traffic flow estimation using probe vehicle data, in 2020 IEEE 7th International Conference on Data Science and Advanced Analytics (DSAA), 579-588 (IEEE).
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  • , , & , Vehicle relocation for ride-hailing, in 2020 IEEE 7th International Conference on Data Science and Advanced Analytics (DSAA), 589-598 (IEEE).
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2019

  • et al., A vocabulary recommendation method for spatiotemporal data discovery based on bayesian network and ontologies, Big Earth Data 3, 220–231.
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  • et al., CrowdZIP: A system to improve reverse ZIP code geocoding using spatial and crowdsourced data (demo paper), in Proceedings of the 27th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems, 588-591 .
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  • , , & , Distance-aware competitive spatiotemporal searching using spatiotemporal resource matrix factorization (GIS cup), in Proceedings of the 27th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems, 624-627 .
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  • & , Investigation design: The structural elements of knowledge-seeking efforts, Data & Knowledge Engineering 119, 71–88.
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  • et al., Location-based social simulation, in Proceedings of the 16th International Symposium on Spatial and Temporal Databases, 218-221 .
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  • et al., Shortest-path diversification through network penalization: A washington DC area case study, in Proceedings of the 12th ACM SIGSPATIAL International Workshop on Computational Transportation Science, 1-10 .
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  • et al., Simulating urban patterns of life: A geo-social data generation framework, in Proceedings of the 27th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems, 576-579 .
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  • et al., Spatiotemporal bus route profiling using odometer data, in Proceedings of the 27th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems, 369-378 .
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  • & , Using OpenStreetMap point-of-interest data to model urban change—a feasibility study, PloS One 14.
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2018

  • et al., Cancer and social media: A comparison of traffic about breast cancer, prostate cancer, and other reproductive cancers on twitter and instagram, Journal of Health Communication 23, 181–189.
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  • et al., Quality assessment and accessibility mapping in an image-based geocrowdsourcing testbed, Cartographica: The International Journal for Geographic Information and Geovisualization 53, 1–14.
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  • et al., Spatio-textual user matching and clustering based on set similarity joins, The VLDB Journal 27, 297–320.
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  • et al., Spatiotemporal traffic volume estimation model based on GPS samples, in Proceedings of the Fifth International ACM SIGMOD Workshop on Managing and Mining Enriched Geo-Spatial Data, 1-6 .
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  • et al., Towards a better understanding of public transportation traffic: A case study of the washington, DC metro, Urban Science 2, 65.
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2017

  • , , & , A layered approach for more robust generation of road network maps from vehicle tracking data, ACM Transactions on Spatial Algorithms and Systems (TSAS) 3, 3.
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  • et al., A unified framework to predict movement, in International Symposium on Spatial and Temporal Databases, 393-397 (Springer, Cham).
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  • et al., Crowdsourcing turning-restrictions from map-matched trajectories, Information Systems 64, 221–236.
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  • et al., Handling uncertainty in geo-spatial data, in Data Engineering (ICDE), 2017 IEEE 33rd International Conference On, 1467-1470 (IEEE).
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  • , , & , Hub labels on the database for large-scale graphs with the COLD framework, GeoInformatica, 1–30.
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  • et al., Knowledge extraction from crowdsourced data for the enrichment of road networks, Geoinformatica 21, 763–795.
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  • et al., Predicting the evolution of narratives in social media, in International Symposium on Spatial and Temporal Databases, 388-392 (Springer, Cham).
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  • et al., Social media engagement with cancer awareness campaigns declined during the 2016 US presidential election, World Medical & Health Policy 9, 456–465.
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  • et al., Zika in twitter: Temporal variations of locations, actors, and concepts, JMIR Public Health and Surveillance 3.
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2016

  • , Crowdsourcing geographic information., in Encyclopedia of Database Systems, to appear (Springer-Verlag).
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  • & , Crowdsourcing turning-restrictions from map-matched trajectories, Information Systems, in press.
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  • , , & , Efficient processing of relevant nearest-neighbor queries, ACM Trans. Spatial Algorithms Syst. 2, 9:1–9:28.
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  • et al., Geo-fingerprinting social media content, in Proceedings of the Third International ACM SIGMOD Workshop on Managing and Mining Enriched Geo-Spatial Data, 5:1-5:6 .
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  • et al., Location estimation using crowdsourced spatial relations, ACM Trans. Spatial Algorithms Syst. 2, 5:1–5:23.
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  • & , ReHub: Extending hub labels for reverse k-nearest neighbor queries on large-scale networks, Journal of Experimental Algorithmics (JEA) 21, 1–13.
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  • et al., Similarity search on spatio-textual point sets, in Proc. 19th Int’l Conf. on Extending Database Technology (EDBT), 329-340 .
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2015

  • et al., A comparison and evaluation of map construction algorithms using vehicle tracking data, GeoInformatica Journal 19, 601–632.
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  • , , & , COLD. Revisiting hub labels on the database for large-scale graphs, in Proc. 14th Int’l Symp. on Spatial and Temporal Databases (SSTD), 22-39 .
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  • et al., Crowdsourcing urban form and function, International Journal of Geographical Information Science 29, 720–741.
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  • et al., Knowledge-enriched route computation, in Proc. 14th Int’l Symp. on Spatial and Temporal Databases (SSTD), 157-176 .
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  • et al., Map Construction Algorithms (Springer-Verlag).
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  • & , ReHub. Extending hub labels for reverse k-nearest neighbor queries on large-scale networks, Journal of Experimental Algorithms 19, in press.
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  • , , & , SALT. A unified framework for all shortest-path query variants on road networks, in Proc. 14th Int’l Symp. on Experimental Algorithms (SEA), 298-311 .
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  • et al., Spatiotemporal behavior profiling: A treasure hunt case study, in Proc. 14th Symp. on Web and Wireless Geographical Information Systems (W2GIS), 143-158 .
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  • et al., Tourismo: A user-preference tourist trip search engine, in Proc. 14th Int’l Symp. on Spatial and Temporal Databases (SSTD), 514-519 .
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2014

  • , , & , Crowdsourcing turning restrictions for OpenStreetMap, in Proc. Mining Urban Data EDBT/ICDT Workshop, 355-362 .
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  • et al., Extraction, integration and analysis of crowdsourced points of interest from multiple web sources, in Proc. 3rd ACM SIGSPATIAL International Workshop on Crowdsourced and Volunteered Geographic Information (GEOCROWD), 16-23 .
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  • et al., Extraction, integration and exploration of crowdsourced geospatial content from multiple web sources (demo), in Proc. 22nd ACM SIGSPATIAL Int’l Conference on Advances in Geographic Information Systems (ACM SIGSPATIAL 2014), 553-556 .
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  • & , GEOCROWD 2013 workshop report: The second int’l workshop on crowdsourced and volunteered geographic information 2013: (Orlando, FL - nov. 5, 2013), SIGSPATIAL Special 6, 11.
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  • , , & , Geosemantic network-of-interest construction using social media data, in Proc. GISCIENCE Conf., 109-125 .
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  • & , GRASP. Extending graph separators for the single-source shortest-path problem, in Proc. 22th Annual European Symposium on Algorithms (ESA), 358-370 .
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  • & , Proceedings of the 13th International Symposium on Web and Wireless Geographical Information Systems (Springer Verlag).
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  • et al., Towards knowledge-enriched path computation, in Proc. 22nd ACM SIGSPATIAL Int’l Conference on Advances in Geographic Information Systems (ACM SIGSPATIAL 2014), 485-488 .
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2013

  • & , Guest editorial: Spatial and temporal databases, GeoInformatica 17, 413–415.
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  • et al., Isochrones, traffic and DEMOgraphics, in Proc. 21th ACM SIGSPATIAL GIS Conference, 558-561 .
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  • & , On quantifying qualitative geospatial data: A probabilistic approach, in Proc. 2nd ACM SIGSPATIAL Int’l Workshop on Crowdsourced and Volunteered Geographic Information (GEOCROWD), 71-78 .
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  • & , Optimizing landmark-based routing and preprocessing, in Proc. 6th ACM SIGSPATIAL Int’l Workshop on Computational Transportation Science (IWCTS), 25-30 .
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  • , , & , Segmentation-based road network construction, in Proc. 21th ACM SIGSPATIAL GIS Conference, 470-473 .
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  • et al., Towards a flexible and scalable fleet management service, in Proc. 6th ACM SIGSPATIAL Int’l Workshop on Computational Transportation Science (IWCTS), 79-84 .
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  • & , User-contributed relevance and nearest neighbor queries, in Proc. 13th Int’l Symposium on Advances in Spatial and Temporal Databases (SSTD), 312-329 (Springer-Verlag).
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2012

  • & , Collaborative geospatial feature search, in Proc. 20th ACM SIGSPATIAL GIS Conference, to appear .
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  • , , & , Crowdsourcing computing resources for shortest-path computation, in Proc. 20th ACM SIGSPATIAL GIS Conference, to appear .
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  • & , On vehicle tracking data-based road network generation, in Proc. 20th ACM SIGSPATIAL GIS Conference, to appear .
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  • , , & , Proceedings of the First ACM SIGSPATIAL International Workshop on Crowdsourced and Volunteered Geographic Information (GEOCROWD) (ACM).
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2011

  • , 12th International Symposium on Advances in Spatial and Temporal Databases (Springer-Verlag).
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  • , , & , Efficient data management in support of shortest-path computation, in Proc. 4th ACM SIGSPATIAL International Workshop on Computational Transportation Science (CTS), 28-33 .
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  • & , Jeocrowd: Collaborative searching of user-generated point datasets, in Proc. ACM SIGSPATIAL Symposium (ACMGIS), 509-512 .
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  • et al., Mobile task computing: Beyond location-based services and ebooks, in W2GIS'11: Proceedings of the 10th International Conference on Web and Wireless Geographical Information Systems, 124-141 (Springer-Verlag).
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  • , On user-generated geocontent, in Proc. 12th Symposium on Spatial and Temporal Databases (SSTD) .
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  • , , & , Opinion mapping travelblogs, in Proc. Terra Cognita Workshop (In Conjunction With International Semantic Web Conf.), 23-36 .
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2010

  • et al., Collaborative information spaces: Research directions at IMIS, in Proc. 2nd ERCIM DIS Workshop on Large-Scale and Federated Information Spaces .
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  • et al., Geoblogging: User-contributed geospatial data collection and fusion, in GIS ‘10: Proceedings of the 18th SIGSPATIAL International Conference on Advances in Geographic Information Systems, 532-533 (ACM).
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  • & , Geospatial route extraction from texts, in DMG ‘10: Proceedings of the 1st ACM SIGSPATIAL International Workshop on Data Mining for Geoinformatics, 29-37 (ACM).
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  • et al., Language-independent access to history textbooks: Utilizing GIS functionality with spatiotemporal and thematic metadata, Transactions of GIS 14, 773–790.
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2009

  • et al., A new perspective on efficient and dependable vehicle routing, in GIS ‘09: Proceedings of the 17th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems, 388-391 (ACM).
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  • et al., Providing universal access to history textbooks: A modified GIS case, in W2GIS ‘09: Proceedings of the 9th International Symposium on Web and Wireless Geographical Information Systems, 87-102 (Springer-Verlag).
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  • et al., Utilizing wireless positioning as a tracking data source, in SSTD ‘09: Proceedings of the 11th International Symposium on Advances in Spatial and Temporal Databases, 171-188 (Springer-Verlag).
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2008

  • et al., Dynamic travel time maps, in Encyclopedia of GIS, 255–260 (Encyclopedia of GIS, Springer-Verlag).
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  • et al., Dynamic travel time provision for road networks, in GIS ‘08: Proceedings of the 16th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems, 1-4 (ACM).
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  • , Floating car data, in Encyclopedia of GIS, 321 (Encyclopedia of GIS, Springer-Verlag).
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  • , Map-matching, in Encyclopedia of GIS, 632–633 (Encyclopedia of GIS, Springer-Verlag).
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  • et al., Qualitative geocoding of persistent web pages, in GIS ‘08: Proceedings of the 16th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems, 1-10 (ACM).
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2007

  • et al., Spatial data management aspects in archaeological excavation documentation, in Proc. AGILE Conf., 287-302 .
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2006

  • , , & , Addressing the need for map-matching speed: Localizing globalb curve-matching algorithms, in SSDBM ‘06: Proceedings of the 18th International Conference on Scientific and Statistical Database Management, 379-388 (IEEE Computer Society).
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  • , , & , Dynamic travel time maps - enabling efficient navigation, in SSDBM ‘06: Proceedings of the 18th International Conference on Scientific and Statistical Database Management, 369-378 (IEEE Computer Society).
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  • & , Introduction to the special issue, Geoinformatica 10, 5–7.
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2005

  • & , Data semantics in location-based services, , 168–195.
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  • , , & , Indeterminacy and spatiotemporal data: Basic definitions and case study, Geoinformatica 9, 211–236.
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  • et al., On map-matching vehicle tracking data, in VLDB ‘05: Proceedings of the 31st International Conference on Very Large Data Bases, 853-864 (VLDB Endowment).
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  • , , & , Practical data management techniques for vehicle tracking data, in ICDE ‘05: Proceedings of the 21st International Conference on Data Engineering, 324-325 (IEEE Computer Society).
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  • & , Trajectory indexing using movement constraints, Geoinformatica 9, 93–115.
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2004

  • , 12th ACM International Workshop on Geographic Information Systems (ACM Press).
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  • , , & , Modeling, storing, and mining moving object databases, in IDEAS ‘04: Proceedings of the International Database Engineering and Applications Symposium, 68-77 (IEEE Computer Society).
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2003

  • et al., Access methods and query processing techniques, in Spatio-Temporal Databases: The CHOROCHRONOS Approach, 203-261 .
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  • et al., DBGlobe: A service-oriented P2P system for global computing, SIGMOD Rec. 32, 77–82.
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  • & , Generating semantics-based trajectories of moving objects, Computers, Environment and Urban Systems 27, 243–263.
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  • & , Indexing of network constrained moving objects, in GIS ‘03: Proceedings of the 11th ACM International Symposium on Advances in Geographic Information Systems, 25-32 (ACM).
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  • , , & , Services-based data management in a global computing environment, in WISEW'03: Proceedings of the Fourth International Conference on Web Information Systems Engineering Workshops, 45-53 (IEEE Computer Society).
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  • , , & , Synthetic and real spatiotemporal datasets, IEEE Data Eng. Bull. 26, 26–32.
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2002

  • , Indexing the trajectories of moving objects, IEEE Data Eng. Bull. 25, 3–9.
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  • , , & , Metadata modeling in a global computing environment, in GIS ‘02: Proceedings of the 10th ACM International Symposium on Advances in Geographic Information Systems, 68-73 (ACM).
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  • , , & , Revisiting r-tree construction principles, in ADBIS ‘02: Proceedings of the 6th East European Conference on Advances in Databases and Information Systems, 149-162 (Springer-Verlag).
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2001

  • & , Capturing fuzziness and uncertainty of spatiotemporal objects, in ADBIS ‘01: Proceedings of the 5th East European Conference on Advances in Databases and Information Systems, 112-126 (Springer-Verlag).
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  • & , Designing ontologies for moving objects applications, in Proc. of the Int’l Workshop on Complex Reasoning on Geographic Data .
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  • et al., Location-based services: A database perspective, in ScanGIS, 59-68 .
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  • & , Querying the trajectories of on-line mobile objects, in MobiDe ‘01: Proceedings of the 2nd ACM International Workshop on Data Engineering for Wireless and Mobile Access, 66-73 (ACM).
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2000

  • , , & , Novel approaches in query processing for moving object trajectories, in VLDB ‘00: Proceedings of the 26th International Conference on Very Large Data Bases, 395-406 (Morgan Kaufmann Publishers Inc.).
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1999

  • & , Capturing the uncertainty of moving-object representations, in SSD ‘99: Proceedings of the 6th International Symposium on Advances in Spatial Databases, 111-132 (Springer-Verlag).
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  • & , Incremental join of time-oriented data, in SSDBM ‘99: Proceedings of the 11th International Conference on Scientific and Statistical Database Management, 232 (IEEE Computer Society).
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1998

  • & , Requirements, definitions, and notations for spatiotemporal application environments, in GIS ‘98: Proceedings of the 6th ACM International Symposium on Advances in Geographic Information Systems, 124-130 (ACM).
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1997

  • , , & , Modeling behavior of geographic objects: An experience with the object modeling technique, in CAiSE ‘97: Proceedings of the 9th International Conference on Advanced Information Systems Engineering, 347-359 (Springer-Verlag).
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  • et al., Structuring space with image schemata: Wayfinding in airports as a case study, in COSIT ‘97: Proceedings of the International Conference on Spatial Information Theory, 85-102 (Springer-Verlag).
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