Filters








146 Hits in 5.6 sec

Coconut: a scalable bottom-up approach for building data series indexes [article]

Haridimos Kondylakis, Niv Dayan, Kostas Zoumpatianos, Themis Palpanas
2020 arXiv   pre-print
As a result, Coconut is able to use bulk-loading techniques that rely on sorting to quickly build a contiguous index using large sequential disk I/Os.  ...  The first innovation in Coconut is an inverted, sortable data series summarization that organizes data series based on a z-order curve, keeping similar series close to each other in the sorted order.  ...  As such we exploit them in order to build a minimal tree in a bottom-up fashion, i.e., a tree that does not contain any raw data series (lines [22] [23] [24] .  ... 
arXiv:2006.13713v1 fatcat:stt5dnstqberjcb26idtpxb76m

Coconut

Haridimos Kondylakis, Niv Dayan, Kostas Zoumpatianos, Themis Palpanas
2018 Proceedings of the VLDB Endowment  
As a result, Coconut is able to use bulk-loading techniques that rely on sorting to quickly build a contiguous index using large sequential disk I/Os.  ...  The first innovation in Coconut is an inverted, sortable data series summarization that organizes data series based on a z-order curve, keeping similar series close to each other in the sorted order.  ...  As such we exploit them in order to build a minimal tree in a bottom-up fashion, i.e., a tree that does not contain any raw data series (lines [22] [23] [24] .  ... 
doi:10.14778/3199517.3199519 fatcat:eliltucsbbge5fpe7iwv7koziy

Coconut: sortable summarizations for scalable indexes over static and streaming data series [article]

Haridimos Kondylakis, Niv Dayan, Kostas Zoumpatianos, Themis Palpanas
2021 arXiv   pre-print
As a result, Coconut is able to use bulk loading and updating techniques that rely on sorting to quickly build and maintain a contiguous index using large sequential disk I/Os.  ...  To address this problem, we present Coconut, the first data series index based on sortable summarizations and the first efficient solution for indexing and querying streaming series.  ...  As such we exploit them in order to build a minimal tree in a bottom-up fashion, i.e., a tree that does not contain any raw data series (lines [22] [23] [24] .  ... 
arXiv:2006.11474v2 fatcat:552r3xccczgdtffkegwreesjbm

EPLA-DSTree: Extending Piecewise Linear Approximation on a Dynamic Segmentation Tree Index in Sensor-cloud Systems

Xie Bin, Qiuhong Li, Yang Wang, Peng Wang
2020 IEEE Access  
In sensor-cloud applications, a huge amount of time series are generated. Efficient similarity search approaches are necessary for processing these sensor time series data.  ...  Experiments show that it has a less index building time and a better query performance.  ...  We also use synthetic data sets of up to 200 million time series in the scalability test. 2) Real Data sets We used a real data set collected in a bridge condition monitoring system.  ... 
doi:10.1109/access.2020.3022959 fatcat:bvv37u46g5atlhi62bxv22stcu

Local Similarity Search on Geolocated Time Series Using Hybrid Indexing [article]

Georgios Chatzigeorgakidis, Dimitrios Skoutas, Kostas Patroumpas, Themis Palpanas, Spiros Athanasiou, Spiros Skiadopoulos
2021 arXiv   pre-print
In this paper, we consider hybrid queries for retrieving geolocated time series based on filters that combine spatial distance and time series similarity.  ...  To efficiently support such queries, we first leverage the state-of-the-art BTSR-tree index, which utilizes bounds over both the locations and the shapes of time series to prune the search space.  ...  In particular, we introduced the BTSR-tree [6] , a hybrid index that first builds an R-tree over the locations of the time series data.  ... 
arXiv:2104.09509v1 fatcat:rc73xob5hbdlxme53ooj2lvy6m

Scaling Distributed Ledgers and Privacy-Preserving Applications [article]

Alberto Sonnino
2021 arXiv   pre-print
Next, we propose FastPay, a high-integrity settlement system for pre-funded payments that can be used as a financial side-infrastructure for Chainspace to support low-latency retail payments.  ...  We then build Byzcuit, a new cross-shard consensus protocol that is immune to those attacks and that is tailored to run at the heart of Chainspace.  ...  However, these approaches lack in performance, scalability, and/or security.  ... 
arXiv:2102.12273v1 fatcat:3twoaysg7rcj7h4yogwsyyzd34

Return of the Lernaean Hydra: Experimental Evaluation of Data Series Approximate Similarity Search [article]

Karima Echihabi, Kostas Zoumpatianos, Themis Palpanas, Houda Benbrahim
2020 arXiv   pre-print
Data series are a special type of multidimensional data present in numerous domains, where similarity search is a key operation that has been extensively studied in the data series literature.  ...  We propose a taxonomy of similarity search techniques that reconciles the terminology used in these two domains, we describe modifications to data series indexing techniques enabling them to answer approximate  ...  Our results show that the methods derived from the exact data series indexing approaches generally surpass the state-of-the-art techniques for approximate search in vector spaces.  ... 
arXiv:2006.11459v1 fatcat:cijhqxhzpbgfjedipgiupptosu

A Lernaean Hydra [chapter]

Vasileios-Arsenios Lioutas
2016 Stroke  
Data series are a special type of multidimensional data present in numerous domains, where similarity search is a key operation that has been extensively studied in the data series literature.  ...  We propose a taxonomy of similarity search techniques that reconciles the terminology used in these two domains, we describe modifications to data series indexing techniques enabling them to answer approximate  ...  Our results show that the methods derived from the exact data series indexing approaches generally surpass the state-of-the-art techniques for approximate search in vector spaces.  ... 
doi:10.1093/med/9780190497255.003.0025 fatcat:brqyhtmrpbablhvxs3ihwqdoai

Twin Subsequence Search in Time Series [article]

Georgios Chatzigeorgakidis, Dimitrios Skoutas, Kostas Patroumpas, Themis Palpanas, Spiros Athanasiou, Spiros Skiadopoulos
2021 arXiv   pre-print
We first show how existing time series indices can be extended to perform twin subsequence search. Then, we introduce TS-Index, a novel index tailored to this problem.  ...  Our experimental evaluation compares these approaches against real time series datasets, and demonstrates that TS-Index can retrieve twin subsequences much faster under various query conditions.  ...  Coconut [9] introduces sortable SAX representations and builds an index in a bottom-up fashion. Finally, ULISSE [11] answers queries of varying length.  ... 
arXiv:2104.06874v1 fatcat:yavze6dygjdgnc6zxjsvdfqf44

Regional Mapping of Plantation Extent Using Multisensor Imagery

Nathan Torbick, Lindsay Ledoux, William Salas, Meng Zhao
2016 Remote Sensing  
The mapping approach was scalable and transferred well across the different geographies and plantation types.  ...  Landsat-8 Operational Land Imager (OLI), Phased Array L-band Synthetic Aperture Radar-2 (PALSAR-2), and Sentinel-1A images were fused within a Classification and Regression Tree (CART) framework using  ...  Thanks to Stephen Hagen for access to the airborne data over West Kalimantan as part of a NASA Carbon Management System (CMS) (Grant #: NNX13AP88G) project.  ... 
doi:10.3390/rs8030236 fatcat:s2hx5hny5bfyrjhnycbhhne7zu

Binary RDF for scalable publishing, exchanging and consumption in the web of data

Javier D. Fernández
2012 Proceedings of the 21st international conference companion on World Wide Web - WWW '12 Companion  
for a long series of shared prefixes.  ...  to build the Wavelet Tree (PS-O index).  ...  Note that the D comp pointers (ptr) and the language and type indexes (lang and dtype) have to be incorporated. • It builds the BTWO * enhanced triple indexes.  ... 
doi:10.1145/2187980.2187997 dblp:conf/www/Fernandez12 fatcat:j2rclthkdnanfbbnwym4smlno4

Full Issue

Full Issue Full Issue
2020 Indonesian Journal of Applied Environmental Studies  
For assisting with the data collection, we thanks to staff of Gunung Gede Pangrango National Park, and Semak Foundation. We thank Daikin Industries for support this study.  ...  A huge thank also given to the colleagues and lecturers at the Study Program of Environmental Management, Pakuan University, for providing motivation to the researcher so that this study can be completed  ...  In IBSAP 2003 was formulated a participatory, bottom-up and transparent approach.  ... 
doi:10.33751/injast.v1i2.2589 fatcat:sc5nmtjw3nexnjv4sl4h2e2pp4

Deep Learning and Earth Observation to Support the Sustainable Development Goals [article]

Claudio Persello, Jan Dirk Wegner, Ronny Hänsch, Devis Tuia, Pedram Ghamisi, Mila Koeva, Gustau Camps-Valls
2021 arXiv   pre-print
This paper reviews current deep learning approaches for Earth observation data, along with their application towards monitoring and achieving the SDGs most impacted by the rapid development of deep learning  ...  New developments and a plethora of applications are already changing the way humanity will face the living planet challenges.  ...  The study introduces a data-driven approach to summarize multiple deprivation variables (both categorical and real-valued) into a single real-valued socioeconomic index, named data-driven index of multiple  ... 
arXiv:2112.11367v1 fatcat:7eve5dr45vcublfqyzzrccuvxa

The challenges of maintaining indigenous ecological knowledge

Joe McCarter, Michael C. Gavin, Sue Baereleo, Mark Love
2014 Ecology and Society  
This is a critical gap, as IEK maintenance is challenging and will require layered and evidence-based solutions. We seek to build a foundation for future approaches to IEK maintenance.  ...  The first case study takes a community-based approach, which has inherent strengths (e.g., localized organization).  ...  This article highlights, however, that issues of power and control are also present in bottom-up approaches to IEK maintenance because power is rarely evenly distributed within communities.  ... 
doi:10.5751/es-06741-190339 fatcat:aqf6adin6naonlpgiyjshhokti

Using visualizations to monitor changes and harvest insights from a global-scale logging infrastructure at Twitter

Krist Wongsuphasawat, Jimmy Lin
2014 2014 IEEE Conference on Visual Analytics Science and Technology (VAST)  
Abstract-Logging user activities is essential to data analysis for internet products and services.  ...  Scribe Radar (Icicle View) -This interactive visualization displays a collection of log events from a hypothetical product that operates on three platforms: strawberry, coconut, and banana.  ...  Approach (2) ended up ignoring a significant portion of the sessions; in fact, rare sessions may be exactly what the data scientist was searching for.  ... 
doi:10.1109/vast.2014.7042487 dblp:conf/ieeevast/WongsuphasawatL14 fatcat:yqajy5bj3zhefodw4pfzicfksm
« Previous Showing results 1 — 15 out of 146 results