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Uncovering Latent Mobility Patterns from Twitter During Mass Events

Enrico Steiger, Timothy Ellersiek, Bernd Resch, Alexander Zipf
2015 GI_FORUM - Journal for Geographic Information Science  
In this paper we therefore present an advanced methodologycal framework, including a generative semantic topic modeling and local spatial autocorrelation approach, to observe both spatiotemporal and semantic  ...  Our results of the observed spatiotemporally and semantically clustered tweets within the selected case study area have shown the possibility of deriving intra-urban event related mobility patterns with  ...  Acknowledgments This research was funded through the graduate scholarship program "Crowd-analyser − spatiotemporal analysis of user-generated content" supported by the state of Baden Wurttemberg.  ... 
doi:10.1553/giscience2015s525 fatcat:mzrutrrjrbcnlfd56hfa7bl4km

DETECTING SPATIAL PATTERNS OF NATURAL HAZARDS FROM THE WIKIPEDIA KNOWLEDGE BASE

J. Fan, K. Stewart
2015 ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
In this work, Wikipedia articles about wildfires are extracted from the Wikipedia database, forming a wildfire corpus and creating a basis for the topic vector analysis.  ...  Over 230,000 geo-tagged articles are then extracted from the Wikipedia database, spatially covering the contiguous United States.  ...  Worboys and Hornsby (2004) also discuss place in the context of a setting for events. Events are described as being inherently spatiotemporal and having spatiotemporal settings.  ... 
doi:10.5194/isprsannals-ii-4-w2-87-2015 fatcat:rqim3dyw3jewdl73jirhmnai3u

Temporal web dynamics and its application to information retrieval

Kira Radinsky, Fernando Diaz, Susan Dumais, Milad Shokouhi, Anlei Dong, Yi Chang
2013 Proceedings of the sixth ACM international conference on Web search and data mining - WSDM '13  
Fogarty and D. Weld. Zoetrope: Interacting with the ephemeral web.  ...   Traditional IR: single snap shot  Word/query trends: aggregates over docs  Document change: aggregates over terms  (Word,Document) trends: Zoetrope  System that enables interaction with historical  ...  Asur and B. A. Huberman. Predicting the future with social media, 2010.]  Predicting Using syntactic and semantic features extracted from text and meta-text  [M. Joshi, D. Das, K. Gimpel, and N. A.  ... 
doi:10.1145/2433396.2433500 dblp:conf/wsdm/RadinskyDDSDC13 fatcat:v3r5yqpnwjcezm35ux4v5eiyse

An Advanced Systematic Literature Review on Spatiotemporal Analyses of Twitter Data

Enrico Steiger, João Porto de Albuquerque, Alexander Zipf
2015 Transactions on GIS  
Reviewed papers and their application domains have shown that the study of geographical processes by using spatiotemporal information from location-based social networks represent a promising and still  ...  The objective of this paper is to conduct a systematic literature review that provides an overview of the current state of research concerning methods and application for spatiotemporal analyses of the  ...  Spatiotemporal analyses of Twitter data -Systematic Literature Review  ... 
doi:10.1111/tgis.12132 fatcat:zfxu7rzev5fohl2ug42valw3ca

MMM-TJU at TRECVID 2010

Anan Liu, Zan Gao
2010 TREC Video Retrieval Evaluation  
Surveillance Event Detection Semantic event detection in the huge amount of surveillance video in both retrospective and real-time styles is essential to a variety of higher-level applications in the public  ...  modeling with the philosophy of bag of spatiotemporal feature (BoSTF).  ...  Then the extracted MoSIFT points are clustered into visual keywords and SVM classifier is used for semantic event modeling.  ... 
dblp:conf/trecvid/LiuG10 fatcat:qgyrmhmsofb33gikvsekbvkfha

Ontology-Based Trajectory Analysis for Semantic Event Detection

Alexia Briassouli, Stamatia Dasiopoulou, Ioannis Kompatsiaris
2007 International Conference on Semantic Computing (ICSC 2007)  
In this paper we present a novel, generally applicable approach, for hierarchical semantic analysis of spatiotemporal video features (trajectories) in order to localize and detect events of interest.  ...  The temporal evolution of the trajectories' geometrical and spatiotemporal characteristics forms the basis on which event detection is performed.  ...  Consequently, it can be used in combination with the ontology designed in Sec. 2, for the extraction of semantics, such as event detection and characterization, from the video sequence.  ... 
doi:10.1109/icosc.2007.4338417 fatcat:7oygpdb5cvfijkyjnzwnukgqxy

Ontology-Based Trajectory Analysis for Semantic Event Detection

Alexia Briassouli, Stamatia Dasiopoulou, Ioannis Kompatsiaris
2007 International Conference on Semantic Computing (ICSC 2007)  
In this paper we present a novel, generally applicable approach, for hierarchical semantic analysis of spatiotemporal video features (trajectories) in order to localize and detect events of interest.  ...  The temporal evolution of the trajectories' geometrical and spatiotemporal characteristics forms the basis on which event detection is performed.  ...  Consequently, it can be used in combination with the ontology designed in Sec. 2, for the extraction of semantics, such as event detection and characterization, from the video sequence.  ... 
doi:10.1109/icsc.2007.33 dblp:conf/semco/BriassouliDK07 fatcat:zbj4la2xdjdtrdwrk4r4ot6r2e

Educing knowledge from text: semantic information extraction of spatial concepts and places

Evangelos Papadias, Margarita Kokla, Eleni Tomai
2021 AGILE: GIScience Series  
Natural language texts provide a wealth of knowledge about geospatial concepts, places, events, and activities that needs to be extracted and formalized to support semantic annotation, knowledge-based  ...  The paper presents a web-based prototype for the extraction of geospatial entities and concepts, and the subsequent semantic visualization and interactive exploration of the extraction results.  ...  Wang and Stewart (2015) extracted spatiotemporal and semantic information for natural hazards from web news reports.  ... 
doi:10.5194/agile-giss-2-38-2021 fatcat:p3cp5pzu4nar5akd27ztj7et54

SemMobi

Fei Wu, Hongjian Wang, Zhenhui Li, Wang-Chien Lee, Zhuojie Huang
2015 Proceedings of the 24th International Conference on World Wide Web - WWW '15 Companion  
At the same time, the large-scale user-generated data from social media, such as geo-tagged tweets, provide rich semantic information about events and locations.  ...  Previous work have used map or POI (point of interest) database as source for semantics. However, those semantics are static, and thus missing important dynamic event information.  ...  The spatiotemporal documents gathered from social media service will be stored in a database after preprocessing.  ... 
doi:10.1145/2740908.2742837 dblp:conf/www/WuWLLH15 fatcat:omqmrz5l7vcclmomozvcbhghn4

GeoBurst

Chao Zhang, Guangyu Zhou, Quan Yuan, Honglei Zhuang, Yu Zheng, Lance Kaplan, Shaowen Wang, Jiawei Han
2016 Proceedings of the 39th International ACM SIGIR conference on Research and Development in Information Retrieval - SIGIR '16  
That said, how to extract quality local events from geo-tagged tweet streams in real time remains largely unsolved so far.  ...  To select truly interesting local events from the candidate list, GEOBURST further summarizes continuous tweet streams and compares the candidates against historical activities to obtain spatiotemporally  ...  Government is authorized to reproduce and distribute reprints for Government purposes notwithstanding any copyright notation hereon.  ... 
doi:10.1145/2911451.2911519 dblp:conf/sigir/ZhangZYZZKWH16 fatcat:uzuccddjwnb6hnph5fllgo47ri

Inferring Implicit Event Locations from Context with Distributional Similarities

Jin-Woo Chung, Wonsuk Yang, Jinseon You, Jong C. Park
2017 Proceedings of the Twenty-Sixth International Joint Conference on Artificial Intelligence  
Automatic event location extraction from text plays a crucial role in many applications such as infectious disease surveillance and natural disaster monitoring.  ...  To overcome this limitation for the first time, we present a system that infers the implicit event locations from a given document.  ...  This highlights the need of inference for event location extraction from text.  ... 
doi:10.24963/ijcai.2017/136 dblp:conf/ijcai/ChungYYP17 fatcat:mmvw3ffjwbhntkasweqhyopzme

Multimedia database management systems

Arif Ghafoor
1995 ACM Computing Surveys  
However, currently this model suffers from the drawback that the extraction of various spatiotemporal and content semantics from this model can be quite cumbersome.  ...  as shown in Figure l(b),' are needed in order to ex- press events and allow content-based in- dexing and retrieval, Spatiotemporal logic can provide a formal framework for representing such  ... 
doi:10.1145/234782.234798 fatcat:lrqmgue5cbfjnjsq5ne3vxyizi

Discovering Spatio-temporal Patterns of Themes in Social Media

Tobore Igbe, Bolanle Ojokoh, Olumide Adewale
2016 Oriental journal of computer science and technology  
Semantic analysis was carried out on the subject by computing the mean occurrence of the subject with the corresponding predicate and object from the total occurrence of the subject.  ...  The proposed model is capable of revealing spatiotemporal pattern for a subject, and can be applied in any area where spatiotemporal factor is to be considered.  ...  Intuitively, documents describing the same event will contain similar sets of keywords, and the graph of keywords for a document collection contains clusters of individual events.  ... 
doi:10.13005/ojcst/09.03.02 fatcat:id4v7rcmg5bnxp7ljz4mlybfdy

Visualization of Clandestine Labs from Seizure Reports: Thematic Mapping and Data Mining Research Directions [article]

William Hsu, Mohammed Abduljabbar, Ryuichi Osuga, Max Lu, Wesam Elshamy
2015 arXiv   pre-print
The problem of spatiotemporal event visualization based on reports entails subtasks ranging from named entity recognition to relationship extraction and mapping of events.  ...  We present an approach to event extraction that is driven by data mining and visualization goals, particularly thematic mapping and trend analysis.  ...  Events that can be localized in space and time form the basis of spatiotemporal event extraction.  ... 
arXiv:1503.01549v1 fatcat:5usymj3c6zhn7jsf426s2mic6a

Spatiotemporal Information Extraction from a Historic Expedition Gazetteer

Mafkereseb Bekele, Rolf de By, Gaurav Singh
2016 ISPRS International Journal of Geo-Information  
Extracting the geospatial information from these documents requires understanding the contextualized entities in the text.  ...  To this end, we developed a semi-automated framework that has multiple Information Retrieval and Natural Language Processing components to extract the spatiotemporal information from a two-volume historic  ...  Acknowledgments: The first author would like to thank the University of Twente for provision of the data during his master's thesis work, and Debebe Ayele Dessalegn for preparing the extracted information  ... 
doi:10.3390/ijgi5120221 fatcat:vuusxo2ijrfh5bkpp3dkm626ni
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