OpenStreetMap (OSM) has been demonstrated to be a valuable source of spatial data in the context of many applications. However concerns still exist regarding the quality of such data and this has limited the proliferation of its use. Consequently much research has been invested in the development of methods for assessing and/or improving the quality of OSM data. However most of these methods require ground-truth data, which, in many cases, may not be available. In this paper we present a novel solution for OSM data quality assessment that does not require ground-truth data. We consider the semantic accuracy of OSM street network data, and in particular, the associated semantic class (road class) information. A machine learning model is proposed that learns the geometrical and topological characteristics of different semantic classes of streets. This model is subsequently used to accurately determine if a street has been assigned a correct/incorrect semantic class.
{"title":"Automated highway tag assessment of OpenStreetMap road networks","authors":"Musfira Jilani, P. Corcoran, M. Bertolotto","doi":"10.1145/2666310.2666476","DOIUrl":"https://doi.org/10.1145/2666310.2666476","url":null,"abstract":"OpenStreetMap (OSM) has been demonstrated to be a valuable source of spatial data in the context of many applications. However concerns still exist regarding the quality of such data and this has limited the proliferation of its use. Consequently much research has been invested in the development of methods for assessing and/or improving the quality of OSM data. However most of these methods require ground-truth data, which, in many cases, may not be available. In this paper we present a novel solution for OSM data quality assessment that does not require ground-truth data. We consider the semantic accuracy of OSM street network data, and in particular, the associated semantic class (road class) information. A machine learning model is proposed that learns the geometrical and topological characteristics of different semantic classes of streets. This model is subsequently used to accurately determine if a street has been assigned a correct/incorrect semantic class.","PeriodicalId":153031,"journal":{"name":"Proceedings of the 22nd ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125283264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Social networks provide rich data sources for analyzing people activities. This paper introduces a mobile recommender system that suggests places to visit to tourists acting in the city of Mexico. The system developed generates itineraries based on the implicit users' behaviors. Recommendations are automatically extracted and analyzed from Twitter thanks to the application of Bayes and Tree algorithms. Suggested itineraries are cross-analyzed to take into account user profiles and preferences. The recommender system provides an augmented reality navigation system that suggests itineraries to the users according to some places of interest. The preliminary prototype developed is an Android app so-called "Turicel Social".
{"title":"A social navigation guide using augmented reality","authors":"F. Mata, Christophe Claramunt","doi":"10.1145/2666310.2666364","DOIUrl":"https://doi.org/10.1145/2666310.2666364","url":null,"abstract":"Social networks provide rich data sources for analyzing people activities. This paper introduces a mobile recommender system that suggests places to visit to tourists acting in the city of Mexico. The system developed generates itineraries based on the implicit users' behaviors. Recommendations are automatically extracted and analyzed from Twitter thanks to the application of Bayes and Tree algorithms. Suggested itineraries are cross-analyzed to take into account user profiles and preferences. The recommender system provides an augmented reality navigation system that suggests itineraries to the users according to some places of interest. The preliminary prototype developed is an Android app so-called \"Turicel Social\".","PeriodicalId":153031,"journal":{"name":"Proceedings of the 22nd ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125986448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Benjamin B. Krogh, N. Pelekis, Y. Theodoridis, K. Torp
In traffic research, management, and planning a number of path-based analyses are heavily used, e.g., for computing turn-times, evaluating green waves, or studying traffic flow. These analyses require retrieving the trajectories that follow the full path being analyzed. Existing path queries cannot sufficiently support such path-based analyses because they retrieve all trajectories that touch any edge in the path. In this paper, we define and formalize the strict path query. This is a novel query type tailored to support path-based analysis, where trajectories must follow all edges in the path. To efficiently support strict path queries, we present a novel NET work-constrained TRAjectory index (NETTRA). This index enables very efficient retrieval of trajectories that follow a specific path, i.e., strict path queries. NETTRA uses a new path encoding scheme that can determine if a trajectory follows a specific path by only retrieving data from the first and last edge in the path. To correctly answer strict path queries existing network-constrained trajectory indexes must retrieve data from all edges in the path. An extensive performance study of NETTRA using a very large real-world trajectory data set, consisting of 1.7 million trajectories (941 million GPS records) and a road network with 1.3 million edges, shows a speed-up of two orders of magnitude compared to state-of-the-art trajectory indexes.
{"title":"Path-based queries on trajectory data","authors":"Benjamin B. Krogh, N. Pelekis, Y. Theodoridis, K. Torp","doi":"10.1145/2666310.2666413","DOIUrl":"https://doi.org/10.1145/2666310.2666413","url":null,"abstract":"In traffic research, management, and planning a number of path-based analyses are heavily used, e.g., for computing turn-times, evaluating green waves, or studying traffic flow. These analyses require retrieving the trajectories that follow the full path being analyzed. Existing path queries cannot sufficiently support such path-based analyses because they retrieve all trajectories that touch any edge in the path. In this paper, we define and formalize the strict path query. This is a novel query type tailored to support path-based analysis, where trajectories must follow all edges in the path. To efficiently support strict path queries, we present a novel NET work-constrained TRAjectory index (NETTRA). This index enables very efficient retrieval of trajectories that follow a specific path, i.e., strict path queries. NETTRA uses a new path encoding scheme that can determine if a trajectory follows a specific path by only retrieving data from the first and last edge in the path. To correctly answer strict path queries existing network-constrained trajectory indexes must retrieve data from all edges in the path. An extensive performance study of NETTRA using a very large real-world trajectory data set, consisting of 1.7 million trajectories (941 million GPS records) and a road network with 1.3 million edges, shows a speed-up of two orders of magnitude compared to state-of-the-art trajectory indexes.","PeriodicalId":153031,"journal":{"name":"Proceedings of the 22nd ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130425031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yao-Yi Chiang, Bo Wu, Akshay Anand, Ketan Akade, Craig A. Knoblock
A significant challenge in handling geographic datasets is that the datasets can come from heterogeneous sources with various data qualities and formats. Before these datasets can be used in a Geographic Information System (GIS) for spatial analysis or to create maps, a typical task is to clean the attribute data and transform the data into a uniform format. However, conventional GIS products focus on manipulating the spatial component of geographic features and only offer basic tools for editing the attribute data (e.g., one row at a time). This limits the capability for handling large datasets in a GIS since manually editing and transforming attribute data between different formats is not practical for thousands of geographic features. In this demo, we present ArcKarma, which is built on our previous work on data transformation, to efficiently clean and transform data attributes in a GIS. ArcKarma generates transformation programs from a few user-provided examples and applies these programs to transform individual attribute columns into the desired formats. We show that ArcKarma produces accurate results and eliminates the need for laborious manual data cleaning and scripting tasks.
{"title":"A system for efficient cleaning and transformation of geospatial data attributes","authors":"Yao-Yi Chiang, Bo Wu, Akshay Anand, Ketan Akade, Craig A. Knoblock","doi":"10.1145/2666310.2666373","DOIUrl":"https://doi.org/10.1145/2666310.2666373","url":null,"abstract":"A significant challenge in handling geographic datasets is that the datasets can come from heterogeneous sources with various data qualities and formats. Before these datasets can be used in a Geographic Information System (GIS) for spatial analysis or to create maps, a typical task is to clean the attribute data and transform the data into a uniform format. However, conventional GIS products focus on manipulating the spatial component of geographic features and only offer basic tools for editing the attribute data (e.g., one row at a time). This limits the capability for handling large datasets in a GIS since manually editing and transforming attribute data between different formats is not practical for thousands of geographic features. In this demo, we present ArcKarma, which is built on our previous work on data transformation, to efficiently clean and transform data attributes in a GIS. ArcKarma generates transformation programs from a few user-provided examples and applies these programs to transform individual attribute columns into the desired formats. We show that ArcKarma produces accurate results and eliminates the need for laborious manual data cleaning and scripting tasks.","PeriodicalId":153031,"journal":{"name":"Proceedings of the 22nd ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130516383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Carniel, Markus Schneider, R. Ciferri, C. D. Ciferri
Spatial database systems and Geographical Information Systems (GIS) are currently only able to handle crisp spatial objects, i.e., objects whose extent, shape, and boundary are precisely determined. However, GIS applications are also interested in managing vague or fuzzy spatial objects. Spatial fuzziness captures the inherent property of many spatial objects in reality that do not have sharp boundaries and interiors or whose boundaries and interiors cannot be precisely determined. While topological relationships have been broadly explored for crisp spatial objects, this is not the case for fuzzy spatial objects. In this paper, we propose a novel model to formally define fuzzy topological predicates for simple and complex fuzzy regions. The model encompasses six fuzzy predicates (overlap, disjoint, inside, contains, equal and meet), wherein here we focus on the fuzzy overlap and the fuzzy disjoint predicates only. For their computation we consider two low-level measures, the degree of membership and the degree of coverage, and map them to high-level fuzzy modifiers and linguistic values respectively that are deployed in spatial queries by end-users.
{"title":"Modeling fuzzy topological predicates for fuzzy regions","authors":"A. Carniel, Markus Schneider, R. Ciferri, C. D. Ciferri","doi":"10.1145/2666310.2666497","DOIUrl":"https://doi.org/10.1145/2666310.2666497","url":null,"abstract":"Spatial database systems and Geographical Information Systems (GIS) are currently only able to handle crisp spatial objects, i.e., objects whose extent, shape, and boundary are precisely determined. However, GIS applications are also interested in managing vague or fuzzy spatial objects. Spatial fuzziness captures the inherent property of many spatial objects in reality that do not have sharp boundaries and interiors or whose boundaries and interiors cannot be precisely determined. While topological relationships have been broadly explored for crisp spatial objects, this is not the case for fuzzy spatial objects. In this paper, we propose a novel model to formally define fuzzy topological predicates for simple and complex fuzzy regions. The model encompasses six fuzzy predicates (overlap, disjoint, inside, contains, equal and meet), wherein here we focus on the fuzzy overlap and the fuzzy disjoint predicates only. For their computation we consider two low-level measures, the degree of membership and the degree of coverage, and map them to high-level fuzzy modifiers and linguistic values respectively that are deployed in spatial queries by end-users.","PeriodicalId":153031,"journal":{"name":"Proceedings of the 22nd ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130682569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Given the increasing prevalence of streaming spatially-referenced datasets resulting from sensor networks usually consisting of text objects of varying length (termed labels) as well as streaming spatially oriented queries leads to closer scrutiny of mapping interfaces to present the data to users. These interfaces must cope with the fact that the labels associated with each location are constantly changing and that there are too many objects to display clearly within the interface. An algorithm meeting these challenges is presented. It differs from classical methods by avoiding expensive pre-computation steps, thereby allowing different labels to be associated with locations without needing to completely recompute the layout. In other words, we are addressing a write-many read-many setting instead of the conventional write-once read-many setting. Our experiments show consistent sub-second query times for query windows that contain as many as 11 million data objects, with only slight differences in the set of displayed labels when compared to an exhaustive baseline algorithm. This enables the algorithm to be used in a mapping application that involves both streaming data and streaming queries such as windowing realized by real-time, continuous zooming and panning operations.
{"title":"Viewing streaming spatially-referenced data at interactive rates","authors":"Shangfu Peng, H. Samet, M. Adelfio","doi":"10.1145/2666310.2666432","DOIUrl":"https://doi.org/10.1145/2666310.2666432","url":null,"abstract":"Given the increasing prevalence of streaming spatially-referenced datasets resulting from sensor networks usually consisting of text objects of varying length (termed labels) as well as streaming spatially oriented queries leads to closer scrutiny of mapping interfaces to present the data to users. These interfaces must cope with the fact that the labels associated with each location are constantly changing and that there are too many objects to display clearly within the interface. An algorithm meeting these challenges is presented. It differs from classical methods by avoiding expensive pre-computation steps, thereby allowing different labels to be associated with locations without needing to completely recompute the layout. In other words, we are addressing a write-many read-many setting instead of the conventional write-once read-many setting. Our experiments show consistent sub-second query times for query windows that contain as many as 11 million data objects, with only slight differences in the set of displayed labels when compared to an exhaustive baseline algorithm. This enables the algorithm to be used in a mapping application that involves both streaming data and streaming queries such as windowing realized by real-time, continuous zooming and panning operations.","PeriodicalId":153031,"journal":{"name":"Proceedings of the 22nd ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133230387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wenli Li, W. Randolph Franklin, Daniel N. Benedetti, S. V. G. Magalhães
This paper presents the optimization and parallelization of the multiple observer siting program, originally developed by Franklin and Vogt. Siting is a compute-intensive application with a large amount of inherent parallelism. The advantage of parallelization is not only a faster program but also the ability to solve bigger problems. We have parallelized the program using two different techniques: OpenMP, using multi-core CPUs, and CUDA, using a general purpose graphics processing unit (GPGPU). Experiment results show that both techniques are very effective. Using the OpenMP program, we are able to site tens of thousands of observers on a 16385 × 16385 terrain in less than 2 minutes, on our workstation with two CPUs and one GPU. The CUDA program achieves the same in about 30 seconds.
{"title":"Parallel multiple observer siting on terrain","authors":"Wenli Li, W. Randolph Franklin, Daniel N. Benedetti, S. V. G. Magalhães","doi":"10.1145/2666310.2666486","DOIUrl":"https://doi.org/10.1145/2666310.2666486","url":null,"abstract":"This paper presents the optimization and parallelization of the multiple observer siting program, originally developed by Franklin and Vogt. Siting is a compute-intensive application with a large amount of inherent parallelism. The advantage of parallelization is not only a faster program but also the ability to solve bigger problems. We have parallelized the program using two different techniques: OpenMP, using multi-core CPUs, and CUDA, using a general purpose graphics processing unit (GPGPU). Experiment results show that both techniques are very effective. Using the OpenMP program, we are able to site tens of thousands of observers on a 16385 × 16385 terrain in less than 2 minutes, on our workstation with two CPUs and one GPU. The CUDA program achieves the same in about 30 seconds.","PeriodicalId":153031,"journal":{"name":"Proceedings of the 22nd ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134343265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mihir Sathe, Craig A. Knoblock, Yao-Yi Chiang, Aaron Harris
Given the increasing popularity and availability of location tracking devices, large quantities of spatiotemporal data are available from many different sources. Quick interactive analysis of such data is important in order to understand the data, identify patterns, and eventually make a marketable product. Since the data do not necessarily follow the relational model and may require flexible processing possibly using advanced machine learning techniques, spatial databases or similar query tools do not make the best means for such analysis. Moreover, the high complexity of geometric operations makes the quick interactive analysis very difficult. In this paper, we present a highly flexible functional query engine that 1) works with multiple schema types, 2) provides fast response times by spatiotemporal indexing and parallelization, 3) helps understand the data using visualizations and 4) is highly extensible to easily add complex functionality. To demonstrate its usefulness, we use our tool to solve a real world problem of crime pattern analysis in Los Angeles County and compare the process with other well known tools.
{"title":"A parallel query engine for interactive spatiotemporal analysis","authors":"Mihir Sathe, Craig A. Knoblock, Yao-Yi Chiang, Aaron Harris","doi":"10.1145/2666310.2666437","DOIUrl":"https://doi.org/10.1145/2666310.2666437","url":null,"abstract":"Given the increasing popularity and availability of location tracking devices, large quantities of spatiotemporal data are available from many different sources. Quick interactive analysis of such data is important in order to understand the data, identify patterns, and eventually make a marketable product. Since the data do not necessarily follow the relational model and may require flexible processing possibly using advanced machine learning techniques, spatial databases or similar query tools do not make the best means for such analysis. Moreover, the high complexity of geometric operations makes the quick interactive analysis very difficult. In this paper, we present a highly flexible functional query engine that 1) works with multiple schema types, 2) provides fast response times by spatiotemporal indexing and parallelization, 3) helps understand the data using visualizations and 4) is highly extensible to easily add complex functionality. To demonstrate its usefulness, we use our tool to solve a real world problem of crime pattern analysis in Los Angeles County and compare the process with other well known tools.","PeriodicalId":153031,"journal":{"name":"Proceedings of the 22nd ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems","volume":"193 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114004515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, we propose two parameterized frameworks, namely the Uniform Watchtower (UW) framework and the Hot zone-based Watchtower (HW) framework, for the evaluation of spatial queries on large road networks. The motivation of this research is twofold: (1) how to answer spatial queries efficiently on large road networks with massive POI data and (2) how to take advantage of social data in spatial query processing. In UW, the network traversal terminates once it acquires the Point of Interest (POI) distance information stored in watchtowers. In HW, by observing that users' movements often exhibit strong spatial patterns, we employ probabilistic clustering to model mobile user check-in data as a mixture of 2-dimensional Gaussian distributions to identify hot zones so that watchtowers can be deployed discriminatorily. Our analyses verify the superiority of HW over UW in terms of query response time.
{"title":"Parameterized spatial query processing based on social probabilistic clustering","authors":"L. Tang, Haiquan Chen, Wei-Shinn Ku, Min-Te Sun","doi":"10.1145/2666310.2666428","DOIUrl":"https://doi.org/10.1145/2666310.2666428","url":null,"abstract":"In this paper, we propose two parameterized frameworks, namely the Uniform Watchtower (UW) framework and the Hot zone-based Watchtower (HW) framework, for the evaluation of spatial queries on large road networks. The motivation of this research is twofold: (1) how to answer spatial queries efficiently on large road networks with massive POI data and (2) how to take advantage of social data in spatial query processing. In UW, the network traversal terminates once it acquires the Point of Interest (POI) distance information stored in watchtowers. In HW, by observing that users' movements often exhibit strong spatial patterns, we employ probabilistic clustering to model mobile user check-in data as a mixture of 2-dimensional Gaussian distributions to identify hot zones so that watchtowers can be deployed discriminatorily. Our analyses verify the superiority of HW over UW in terms of query response time.","PeriodicalId":153031,"journal":{"name":"Proceedings of the 22nd ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems","volume":"186 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114049352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Map generalization is commonly used in many GIS applications to produce maps with less detail so as to reduce the mapping complexity. Different from common simplifying strategies which simplify individual geometry objects separately, in this paper we consider the problem of generalizing the geometry objects under the topological constraints among the geometries and given constraining points. We propose a Cross-line algorithm to simplify the map while preserving the topological constraints. The proposed algorithm is extensively evaluated on five real map datasets and large synthetic datasets, and the results show that our proposed approach can greatly simplify the map with extremely high correctness and excellent efficiency.
{"title":"A fast algorithm of geometry generalization","authors":"Yuwei Wang, Danhuai Guo, Kuien Liu, Yan Xiong","doi":"10.1145/2666310.2666420","DOIUrl":"https://doi.org/10.1145/2666310.2666420","url":null,"abstract":"Map generalization is commonly used in many GIS applications to produce maps with less detail so as to reduce the mapping complexity. Different from common simplifying strategies which simplify individual geometry objects separately, in this paper we consider the problem of generalizing the geometry objects under the topological constraints among the geometries and given constraining points. We propose a Cross-line algorithm to simplify the map while preserving the topological constraints. The proposed algorithm is extensively evaluated on five real map datasets and large synthetic datasets, and the results show that our proposed approach can greatly simplify the map with extremely high correctness and excellent efficiency.","PeriodicalId":153031,"journal":{"name":"Proceedings of the 22nd ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems","volume":"1008 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116246698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}