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The Potential of Time Series Merged from Landsat-5 TM and HJ-1 CCD for Crop Classification: A Case Study for Bole and Manas Counties in Xinjiang, China

Pengyu Hao, Li Wang, Zheng Niu, Abdullah Aablikim, Ni Huang, Shiguang Xu, Fang Chen
2014 Remote Sensing  
The results showed that time series in optimal temporal windows can achieve high classification accuracies.  ...  A support vector machine (SVM) was then used to compare the classification accuracy of the optimal temporal windows and the entire time series.  ...  Author Contributions Pentyu Hao, Li Wang and Zheng Niu designed the research, Li Wang and Abdullah Aablikim collected the field data.  ... 
doi:10.3390/rs6087610 fatcat:rerglu4xtndfbcomimc2jrhfuq

The quest for automated land cover change detection using satellite time series data

B. P. Salmon, J. C. Olivier, W. Kleynhans, K. J. Wessels, F. van den Bergh
2009 2009 IEEE International Geoscience and Remote Sensing Symposium  
This paper shows that a feedforward Multilayer Perceptron (MLP) operating over a temporal sliding window of multispectral time series MODerate-resolution Imaging Spectroradiometer (MODIS) satellite data  ...  It is shown that for this type of simulated land cover change, where land cover change was abrupt, a short-term FFT window of 18 months or less, using only the two NDVI spectral bands of MODIS data was  ...  The MLP was required to process time series data and detect land cover change as a function of time.  ... 
doi:10.1109/igarss.2009.5417328 dblp:conf/igarss/SalmonOKWB09 fatcat:s6wy566cizbvdbznqhft4s7jme

On-line sensing task optimization for shared sensors

Arsalan Tavakoli, Aman Kansal, Suman Nath
2010 Proceedings of the 9th ACM/IEEE International Conference on Information Processing in Sensor Networks - IPSN '10  
Specifically, we use an interval-cover graph to minimize communication redundancies and a joint data flow graph optimization to remove computational redundancies.  ...  To address this, we develop methods that detect when common data and common stream processing is requested by multiple applications, including cases where only some of the data is shared or only intermediate  ...  Note that in addition to spatial computation (i.e. computation that uses data from mutliple sensors) the tasks also contain temporal computation (such as taking average/minimum over a time window of the  ... 
doi:10.1145/1791212.1791219 dblp:conf/ipsn/TavakoliKN10 fatcat:fmzhr3zunzdnjnhs4jtgt7xt2y

Meta-optimization of the Extended Kalman Filter's parameters for improved feature extraction on hyper-temporal images

B.P. Salmon, W. Kleynhans, F. van den Bergh, J.C. Olivier, W.J. Marais, K.J. Wessels
2011 2011 IEEE International Geoscience and Remote Sensing Symposium  
The approach is based on a unsupervised search algorithm over an appropriately defined manifold using spatial and temporal information.  ...  This paper proposes a meta-optimization approach for setting the parameters of the non-linear Extended Kalman Filter to rapidly and efficiently estimate the features for the pair of triply modulated cosine  ...  A suitable search algorithm was applied to find a optimal candidate manifold. RESULTS A spatio-temporal window was used to extract a set of subsequences from the time series data set.  ... 
doi:10.1109/igarss.2011.6049730 dblp:conf/igarss/SalmonKBOMW11 fatcat:rf72iqeujnhibnfvqgk57h43pa

BMRC: A Bitmap-Based Maximum Range Counting Approach for Temporal Data in Sensor Monitoring Networks

Bin Cao, Wangyuan Chen, Ying Shen, Chenyu Hou, Jung Kim, Lifeng Yu
2017 Sensors  
Since sensor nodes can update their temporal data at high frequency, we present a scalable strategy to support the real-time insert and delete operations.  ...  disasters and traffic accidents, which generate large-scale temporal data.  ...  Conflicts of Interest: The authors declare no conflict of interest. Sensors 2017, 17, 2051  ... 
doi:10.3390/s17092051 pmid:28880252 pmcid:PMC5620496 fatcat:odhfjcsiczc27d5vbnvgc3yfhq

Temporal vertex cover with a sliding time window

Eleni C. Akrida, George B. Mertzios, Paul G. Spirakis, Viktor Zamaraev
2019 Journal of computer and system sciences (Print)  
Instead, 89 every edge must be covered at least once within every small ∆-window of time (for an 90 appropriate value of ∆), regardless of how large the lifetime is; this gives rise to our second 91 optimization  ...  problem, namely Sliding Window Temporal Vertex Cover (for short, 92 SW-TVC).  ...  We are now ready to introduce the notion of a sliding ∆-window temporal vertex cover and the optimization problem Sliding Window Temporal Vertex Cover.Definition 4.  ... 
doi:10.1016/j.jcss.2019.08.002 fatcat:m23ibl7ahfcfvfyex2ibbhm5ca

The use of a Multilayer Perceptron for detecting new human settlements from a time series of MODIS images

B.P. Salmon, J.C. Olivier, W. Kleynhans, K.J. Wessels, F. van den Bergh, K.C. Steenkamp
2011 International Journal of Applied Earth Observation and Geoinformation  
This paper presents a novel land cover change detection method that employs a sliding window over hyper-temporal multi-spectral images acquired from the 7 bands of the MODerate-resolution Imaging Spectroradiometer  ...  It is shown that a sliding window of 6 months using all 7 bands of MODIS data is sufficient to detect land cover change reliably.  ...  Acknowledgements The research was funded by the CSIR Strategic Research Panel. Alex Fortesque and Naledzani Mudau of CSIR, Satellite Application Centre (SAC) provided data on settlements.  ... 
doi:10.1016/j.jag.2011.06.007 fatcat:dwhvs4tdxreijno76pn7y74g7u

Contrast-kinetics-resolved whole-heart coronary MRA using 3DPR

Peng Lai, Feng Huang, Yu Li, Sonia Nielles-Vallespin, Xiaoming Bi, Renate Jerecic, Debiao Li
2010 Magnetic Resonance in Medicine  
With this method, data acquisition was started simultaneously with contrast injection. Sequential time frames were reconstructed by employing a sliding window scheme with temporal tornado filtering.  ...  Additionally, a self-timing method was developed to monitor contrast enhancement during a scan and automatically determine the peak enhancement time around which optimal temporal frames were reconstructed  ...  In our current work, data acquisition was repeated within a fixed long duration of 9 min to ensure covering the optimal acquisition window.  ... 
doi:10.1002/mrm.22246 pmid:20373398 pmcid:PMC2852268 fatcat:ceftijz2jbh5hpefkfnpgweqeu

A hierarchical approach for the selection of optical ground stations maximizing the data transfer from low-earth observation satellites

Mikael Capelle, Marie-Jose Huguet, Nicolas Jozefowiez, Xavier Olive
2017 2017 IEEE International Conference on Communications (ICC)  
The efficiency of this method is evaluated on several instances based on real ground station networks and on cloud cover throughout the last twenty years.  ...  hierarchical approach for the selection of optical ground stations maximizing the data transfer from low-earth observation satellites.  ...  , we first approximate c i (t) the cloud cover ratio (c i (t) ∈ [0, 1]) over the station i at time t: Since this dataset has a 0.75×0.75 degrees spatial resolution and a 6 hours temporal resolution, we  ... 
doi:10.1109/icc.2017.7996550 dblp:conf/icc/CapelleHJO17 fatcat:rmqr6rvobfewld3jkwjpvp2m44

Temporal Vertex Cover with a Sliding Time Window [article]

Eleni C. Akrida, George B. Mertzios, Paul G. Spirakis, Viktor Zamaraev
2019 arXiv   pre-print
In our first problem, Temporal Vertex Cover, the aim is to cover every edge at least once during the lifetime of the temporal graph, where an edge can be covered by one of its endpoints, only at a time  ...  In our second, more pragmatic variation Sliding Window Temporal Vertex Cover, we are also given a natural number Δ, and our aim is to cover every edge at least once at every Δ consecutive time steps.  ...  We are now ready to introduce the notion of a sliding ∆-window temporal vertex cover and the optimization problem Sliding Window Temporal Vertex Cover. Definition 4.  ... 
arXiv:1802.07103v3 fatcat:xpqeao5mbrgxbk5jtrshwwb6h4

Semantics of Spatially-Aware Windows Over Streaming Moving Objects

Kostas Patroumpas, Timos Sellis
2007 2007 International Conference on Mobile Data Management  
Several window constructs are usually specified in continuous queries over data streams as a means of limiting the amount of data processed each time and thus providing real-time responses.  ...  Current research has mostly focused on tackling the temporal volatility of the stream, overlooking other inherent features of incoming items.  ...  In terms of query specification, we propose a generic SQL clause like: [EXTENT cover RANGE time SHIFT BY(dx, dy, dt)] We borrow from CQL [2] , keyword RANGE time to denote the temporal scope of the window  ... 
doi:10.1109/mdm.2007.17 dblp:conf/mdm/PatroumpasS07 fatcat:ub74aatkezcvxlka5iageleqmm

Monitoring Deforestation at Sub-Annual Scales as Extreme Events in Landsat Data Cubes

Eliakim Hamunyela, Jan Verbesselt, Sytze de Bruin, Martin Herold
2016 Remote Sensing  
data cube defined over reference period.  ...  First we spatially normalised observations in the local space-time data cube to reduce seasonality.  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs8080651 fatcat:yu2m5bo44rdmbogbbdqyjttt5i

Beyond Adherence Thresholds: A Simulation Study of the Optimal Classification of Longitudinal Adherence Trajectories From Medication Refill Histories

Samuel S. Allemann, Dan Dediu, Alexandra Lelia Dima
2019 Frontiers in Pharmacology  
Thresholds to distinguish adherence from non-adherence typically refer to an aggregated value across the entire observation period, disregarding differences in adherence over time.  ...  shorter non-overlapping windows for the identification of different adherence patterns from medication refill data.  ...  Window Size and Overlap The sliding window size refers to the time covered by each window, e.g., 30 days.  ... 
doi:10.3389/fphar.2019.00383 pmid:31105559 pmcid:PMC6499004 fatcat:dx7lyuez2ne4tmictu5ua7jdra

Temporal order optimizations of incremental joins for composite event detection

François Bry, Michael Eckert
2007 Proceedings of the 2007 inaugural international conference on Distributed event-based systems - DEBS '07  
time windows for negation and aggregation.  ...  Queries for composite events typically involve the four complementary dimensions of event data, event composition, relationships between events (esp. temporal and causal), and accumulating events over  ...  Acknowledgments This research has been funded by the European Commission and by the Swiss Federal Office for Education and Science within the 6th Framework Programme project REWERSE number 506779 (http  ... 
doi:10.1145/1266894.1266910 dblp:conf/debs/BryE07 fatcat:v2bwpxu6mzg6ffz4pixadg4y5q

A Spectral Unmixing Model for the Integration of Multi-Sensor Imagery: A Tool to Generate Consistent Time Series Data

Georgia Doxani, Zina Mitraka, Ferran Gascon, Philippe Goryl, Bojan Bojkov
2015 Remote Sensing  
The main goal is to fill the data gaps in the S-2 record, based on the more frequent information of the S-3 time series.  ...  The Sentinel missions have been designed to support the operational services of the Copernicus program, ensuring long-term availability of data for a wide range of spectral, spatial and temporal resolutions  ...  Acknowledgments The authors would like to thank the European Space Agency (ESA) and the French Space Agency CNES (Centre National d'Etudes Spatiales) for providing the SPOT-4 (Take 5) time series datasets  ... 
doi:10.3390/rs71014000 fatcat:nwphdqpr3bbxxj4duhdjwcgwwq
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