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Database Technology for Processing Temporal Data (Invited Paper)

Michael H. Böhlen, Anton Dignös, Johann Gamper, Christian S. Jensen, Michael Wagner
2018 International Symposium/Workshop on Temporal Representation and Reasoning  
Despite the ubiquity of temporal data and considerable research on processing such data, database systems largely remain designed for processing the current state of some modeled reality.  ...  New challenges for processing temporal data arise with multiple dimensions of time and the increasing amounts of data, including time series data that represent a special kind of temporal data.  ...  representation and the point-based conceptual model.  ... 
doi:10.4230/lipics.time.2018.2 dblp:conf/time/BohlenDGJ18 fatcat:j3kfsfijijfi7o6wpsytjbnw7u

Comprehensive and interactive temporal query processing with SAP HANA

Martin Kaufmann, Panagiotis Vagenas, Peter M. Fischer, Donald Kossmann, Franz Färber
2013 Proceedings of the VLDB Endowment  
As we will show on a workload based on real customer use cases, it achieves predictable and interactive query performance for a wide range of temporal query types and data sizes.  ...  In this demo, we present a prototype of a main memory database system which provides a wide range of temporal operators featuring predictable and interactive response times.  ...  Temporal Aggregation In contrast to Time Travel, which goes back to a single point in time, Temporal Aggregation considers a sequence of versions to compute an aggregated value for a temporal range.  ... 
doi:10.14778/2536274.2536278 fatcat:4cj3l2ju3bfzzmhhcysdzf2uq4

A demonstration of Shahed: A MapReduce-based system for querying and visualizing satellite data

Ahmed Eldawy, Saif Alharthi, Abdulhadi Alzaidy, Anas Daghistani, Sohaib Ghani, Saleh Basalamah, Mohamed F. Mokbel
2015 2015 IEEE 31st International Conference on Data Engineering  
This demo gives users a hands-on experience with Shahed through a map-based web interface in which users can browse the available datasets using the map, issue spatiotemporal queries, and visualize the  ...  The indexing module organizes the data in a novel multi-resolution spatio-temporal index designed for satellite data.  ...  The x-estimate is computed using a linear interpolation function based on the two closest points on the same horizontal line.  ... 
doi:10.1109/icde.2015.7113397 dblp:conf/icde/EldawyAADGBM15 fatcat:viwb3q2235eavhtmyk7ppd46gi

Parallel online spatial and temporal aggregations on multi-core CPUs and many-core GPUs

Jianting Zhang, Simin You, Le Gruenwald
2014 Information Systems  
After spatially associating points with road segments, spatial, temporal and spatiotemporal aggregations are reduced to relational aggregations and can be processed in the order of a fraction of a second  ...  Unfortunately, existing spatial, temporal and spatiotemporal OLAP techniques are mostly based on traditional computing frameworks, i.e., disk-resident systems on uniprocessors based on serial algorithms  ...  Hongmian Gong at CUNY Hunter College for insightful discussions on urban applications of GPS data.  ... 
doi:10.1016/j.is.2014.01.005 fatcat:y43k2qlcqrg6lnt5ryitfnpahy

Probabilistic temporal networks: A unified framework for reasoning with time and uncertainty

Eugene Santos, Joel D. Young
1999 International Journal of Approximate Reasoning  
These processes change over time in response to both internal and external stimuli as well as to the passage of time itself.  ...  The model allows representation of time constrained causality, of when and if events occur, and of the periodic and recurrent nature of processes.  ...  The time-sliced approaches mentioned above are based on point models of time and, as such, require that events occur instantaneously.  ... 
doi:10.1016/s0888-613x(99)00009-2 fatcat:nqtiq4xqaneizcrjl43gvqconm

High-performance online spatial and temporal aggregations on multi-core CPUs and many-core GPUs

Jianting Zhang, Simin You, Le Gruenwald
2012 Proceedings of the fifteenth international workshop on Data warehousing and OLAP - DOLAP '12  
")Finding the nearest tax blocks for 170 million taxi pickup locations (to aggregate based on tax block types) -Using open source libspatiaindex+GDAL (to avoid database overhead) Table 2 . 2 and Motivation  ...  N1-# of point locations; N2-# of point quadrants t1: time to generate point quadrants t2:time to filter bounding boxes (point quadrants/street segments) t3: time to compute distances and assign identifiers  ...  in about 15 seconds and achieved 13X speedup over optimized serial CPU implementation. • Spatial, temporal and spatiotemporal aggregations can be processed in the order of a fraction of a second on GPUs  ... 
doi:10.1145/2390045.2390060 dblp:conf/dolap/ZhangYG12 fatcat:sj4qc7iw75dlfmuduc22y5vofq

Spatio-temporal aggregation of European air quality observations in the Sensor Web

Christoph Stasch, Theodor Foerster, Christian Autermann, Edzer Pebesma
2012 Computers & Geosciences  
In particular, we define a tailored observation model for different aggregation levels, a process model for aggregation processes and a Spatio-Temporal Aggregation Service.  ...  However, as observations differ in spatio-temporal coverage and resolution, aggregation of observations in space and time is needed.  ...  Currently, it provides means to aggregate points to polygons in 306 space and to partition temporal extents of observations into time intervals. 307 Supported aggregation functions for space and time are  ... 
doi:10.1016/j.cageo.2011.11.008 fatcat:tjtpr3d6svganlqqd7cccaxwim

An efficient spatio-temporal index for spatio-temporal query in wireless sensor networks

2017 KSII Transactions on Internet and Information Systems  
expanded into the domain of time.  ...  In this thesis, I propose IR-tree(Itinerary-based R-tree) in order to solve the existing problem of spatial query processing method and for more efficient processing and for the spatiotemporal query that  ...  On the other hand, CDQO algorithm that processes multiqueries at the same time is based on Quad-tree structure.  ... 
doi:10.3837/tiis.2017.10.012 fatcat:juels3v2evc2tlbfaiizs6pd4y

Effective Temporal Aggregation Using Point-Based Trees [chapter]

Jong Soo Kim, Sung Tak Kang, Myoung Ho Kim
1999 Lecture Notes in Computer Science  
In this paper, we propose a new tree structure for temporal aggregation, called PA-tree, and aggregate processing method based on the PA-tree.  ...  The aggregation in temporal databases, that is, temporal aggregation is an extension of conventional aggregation on the domain and range of aggregates to include time concept.  ...  In this paper, we propose the Point-based Aggregation tree(PA-tree), a n e w balanced tree structure for e cient temporal aggregation, and the aggregate processing techniques on the PA-tree.  ... 
doi:10.1007/3-540-48309-8_96 fatcat:3bo6gz6nkzd3pe6d23rcft6tsa

Generation of Rules from Ontologies for High-Level Scene Interpretation [chapter]

Wilfried Bohlken, Bernd Neumann
2009 Lecture Notes in Computer Science  
In this paper, a novel architecture for high-level scene interpretation is introduced, which is based on the generation of rules from an OWL-DL ontology.  ...  Furthermore the integration of constraints -which are essential for scene interpretation -is demonstrated with a temporal constraint net, and it is shown how parallel computing of alternatives can be realised  ...  As the propagation of values through the constraint net has a procedural character and can effect all time points -i.e. not only the time points in one single aggregate -it is reasonable and efficient  ... 
doi:10.1007/978-3-642-04985-9_11 fatcat:nuvg7bsxcnbbtksotdopyoctnq

Spatio-Temporal Configurations of Human-Caused Fires in Spain through Point Patterns

Sergi Costafreda-Aumedes, Carles Comas, Cristina Vega-Garcia
2016 Forests  
A few studies have focused on the temporal pattern of fire ignitions; [19] found temporal aggregations using temporal trajectory metrics of wildfire ignition densities, while [20] found temporal aggregations  ...  Wildfire occurrences have also been analysed as points placed within a spatio-temporal region using point process statistical tools.  ...  with point intensity (3) based on a Monte Carlo test.  ... 
doi:10.3390/f7090185 fatcat:qrvqzckzebao7kfcrtwv3i43qu

Aggregating Linked Sensor Data

Christoph Stasch, Sven Schade, Alejandro Llaves, Krzysztof Janowicz, Arne Bröring
2011 International Semantic Web Conference  
In this paper, we investigate how work on sensor observation aggregation can be incorporated into a Linked Data framework focusing on external linkage as well as provenance information.  ...  We show that Linked Data adds new aspects to the aggregation problem, e.g., whether external links from one of the original observations can be preserved for the aggregate.  ...  (FP7-248488, http://www.uncertweb.org/), ENVIROFI (FP7-284898, http://www.envirofi.eu/), ENVISION (FP7-249170, http:// www.envision-project.eu/), and through the International Research Training Group on  ... 
dblp:conf/semweb/StaschSLJB11 fatcat:2ckjfst6ibgglpagt5oiwuhw6e

Spatiotemporal aggregate computation: a survey

I.F.V. Lopez, R.T. Snodgrass, Bongki Moon
2005 IEEE Transactions on Knowledge and Data Engineering  
At the same time, it allows us to identify opportunities for research on types of aggregate queries that have not been studied.  ...  In this paper, we study the most relevant techniques for the evaluation of aggregate queries on spatial, temporal, and spatiotemporal data.  ...  During this process, collections of tuples are generated based on temporal grouping and an aggregate function is applied to each collection.  ... 
doi:10.1109/tkde.2005.34 fatcat:j54z4j2chzgchnyqdwoilwnpjy

A HYBRID PULL-PUSH SYSTEM FOR NEAR REAL-TIME NOTIFICATIONS ON SENSOR WEB

C. Y. Huang, S. Liang
2012 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
However, with the growing amount of sensor data, the traditional request/response communication model becomes inefficient as it is based on point-to-point pulling interactions between users and data providers  ...  The preliminary experimental results indicate that the proposed system is able to fetch near real time sensor streams from pull-based sensor web services.  ...  ACKNOWLEDGEMENTS The authors would like to thank CANARIE, Cybera, Alberta Innovates Technology Futures, and Microsoft Research for their supports on this project.  ... 
doi:10.5194/isprsarchives-xxxix-b4-421-2012 fatcat:f73lyukqfffevfy6ijx7y2qomi

Visualizing large sensor network data sets in space and time with vizzly

Matthias Keller, Jan Beutel, Olga Saukh, Lothar Thiele
2012 37th Annual IEEE Conference on Local Computer Networks -- Workshops  
A user is completely free in selecting sensor data based on time and location, suitable levels of temporal and spatial detail are automatically chosen by the Vizzly server.  ...  Vizzly has already been successfully integrated into the PermaSense and OpenSense projects, a single instance is currently handling more than 550 millions of data points.  ...  Based on the length of the time period of interest, Vizzly automatically chooses the level of temporal detail that is used as the input for the spatial aggregation step.  ... 
doi:10.1109/lcnw.2012.6424084 dblp:conf/lcn/KellerBST12 fatcat:7ddelfhdgjb75ezey4jwyetevy
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