Filters








57,510 Hits in 2.5 sec

Using a POWDER Triple Store for Boosting the Real-time Performance of Global Agricultural Data Infrastructures

Pythagoras Karampiperis, Nikos Manouselis, Stasinos Konstantopoulos
2012 Procedia Computer Science  
of URIs to compress data source annotations about extremely large datasets; and (b) how query decomposition, source selection, and distributed querying methods can be designed, that take advantage of  ...  Transparent relegation and translation relies on detailed and accurate data summaries and other data source annotations, and with increased data volumes and heterogeneity managing these annotations, it  ...  That is, 1 triple with meta-information is held in the query decomposition and data selection node for every 100 triples in the distributed data sources.  ... 
doi:10.1016/j.procs.2012.04.173 fatcat:72n2ndghabae3afvsebr3ilss4

Derby/S

Anja Klein, Rainer Gemulla, Philipp Rösch, Wolfgang Lehner
2006 Proceedings of the 2006 ACM SIGMOD international conference on Management of data - SIGMOD '06  
Although approximate query processing is a prominent way to cope with the requirements of data analysis applications, current database systems do not provide integrated and comprehensive support for these  ...  To improve this situation, we propose an SQL extension-called SQL/S-for approximate query answering using random samples, and present a prototypical implementation within the engine of the open-source  ...  Such error bounds are a key requirement for any approximate answer.  ... 
doi:10.1145/1142473.1142579 dblp:conf/sigmod/KleinGRL06 fatcat:4xpodugrybd4jnfconq6kgcfgi

HiBISCuS: Hypergraph-Based Source Selection for SPARQL Endpoint Federation [chapter]

Muhammad Saleem, Axel-Cyrille Ngonga Ngomo
2014 Lecture Notes in Computer Science  
Our approach can be directly combined with existing SPARQL query federation engines to achieve the same recall while querying fewer data sources.  ...  Previous works have focused on generating optimized query execution plans for fast result retrieval.  ...  ST** represents the source selection time for HiBISCuS (AD,warm) with #A =0 for all queries.  ... 
doi:10.1007/978-3-319-07443-6_13 fatcat:u3fsuuaqgfdnhnro554px2oonq

StreamApprox

Do Le Quoc, Ruichuan Chen, Pramod Bhatotia, Christof Fetzer, Volker Hilt, Thorsten Strufe
2017 Proceedings of the 18th ACM/IFIP/USENIX Middleware Conference on - Middleware '17  
To realize this idea, we designed an online stratified reservoir sampling algorithm to produce approximate output with rigorous error bounds.  ...  Approximate computing aims for efficient execution of workflows where an approximate output is sufficient instead of the exact output.  ...  Rellermeyer for their helpful comments.  ... 
doi:10.1145/3135974.3135989 dblp:conf/middleware/QuocCBFHS17 fatcat:2zlds3w2uzbzvdga6426whk474

An Architecture for Approximate Real-Time Query Optimization and Processing

Anna Yarygina, Boris Novikov
2014 Spring Young Researchers Colloquium on Databases and Information Systems  
We discuss architecture of an extendable system for optimization and execution of approximate complex queries formulated in similarity-based declarative query language.  ...  A growing demand to process huge amounts of data under real-time requirements as well as advanced similaritybased models raises the need in approximate processing.  ...  Approximate queries can be annotated with either an error bound, or a time constraint, based on which the system selects an appropriate sample to evaluate the query.  ... 
dblp:conf/syrcodis/YaryginaN14 fatcat:vfmcacoygzbslgl7rc74zhvwy4

Recent Advances in Computation and Combinatorial Optimization

Xiaodong Hu, Jie Wang
2009 Algorithmica  
to improved exact algorithms for classic problems of enumerating cuts, from low-rank matrix factorization and its applications to approximation algorithms for the selected-internal Steiner minimum trees  ...  , and from resource bounded frequency computations to quantum separation of local search and fixed point computation.  ...  Minnameier's paper deals with resource bounded frequency computations.  ... 
doi:10.1007/s00453-009-9374-4 fatcat:ik3eoowkq5daxndcb2wjch2tmm

Approximate Edge Analytics for the IoT Ecosystem [article]

Zhenyu Wen, Do Le Quoc, Pramod Bhatotia, Ruichuan Chen, Myungjin Lee
2018 arXiv   pre-print
To realize this idea, we designed an online hierarchical stratified reservoir sampling algorithm that uses edge computing resources to produce approximate output with rigorous error bounds.  ...  In this work, we make a case for approximate computing for data analytics in IoT settings.  ...  On top of this feature, APPROXIOT produces an approximate query result with rigorous error bounds.  ... 
arXiv:1805.05674v1 fatcat:ly7rektoyvgkddk7zqczrjnrl4

Improving the real-time performance of heterogeneous extremely large datasets

Stasinos Konstantopoulos, Antonis Koukourikos, Pythagoras Karampiperis
2013 Proceedings of the 17th Panhellenic Conference on Informatics - PCI '13  
Furthermore, we discuss a novel solution for the scalable storing data summaries in the form of metadata for the purposes of source selection and source schema coordination in large-scale, heterogeneous  ...  federations of semantic querying endpoints.  ...  upon methods for approximately joining distributed query results and for distributed and approximate inference.  ... 
doi:10.1145/2491845.2491877 dblp:conf/pci/KonstantopoulosKK13 fatcat:dlvr2msfzbdffcldx4rus2ysqa

Herding "small" streaming queries

Bo Zong, Christos Gkantsidis, Milan Vojnovic
2015 Proceedings of the 9th ACM International Conference on Distributed Event-Based Systems - DEBS '15  
We propose approximation algorithms and derive approximation bounds for the following cases (a) the offline case where queries are stable and known ahead of time, akin to an "oracle", and (b) the online  ...  A further complication arises from the requirement to allow the queries to read events from multiple sources concurrently (i.e., to join multiple streams).  ...  Acknowledgments This work benefited from numerous useful discussions with a number of colleagues from Microsoft Bing IPE team and Microsoft Research, including (in alphabetical order) Mike Andrews, JP  ... 
doi:10.1145/2675743.2771825 dblp:conf/debs/ZongGV15 fatcat:b4e7xm4q2ndk7bi6jiysd2xena

Approximate Stream Analytics in Apache Flink and Apache Spark Streaming [article]

Do Le Quoc, Ruichuan Chen, Pramod Bhatotia, Christof Fetze, Volker Hilt, Thorsten Strufe
2017 arXiv   pre-print
To realize this idea, we designed an online stratified reservoir sampling algorithm to produce approximate output with rigorous error bounds.  ...  Approximate computing aims for efficient execution of workflows where an approximate output is sufficient instead of the exact output.  ...  As the last step, we run an error estimation mechanism (as described in §3.3) to compute the error bounds for the approximate query result in the form of output ±error bound.  ... 
arXiv:1709.02946v1 fatcat:ejcj5eugkjbxpo5bet22dhv7jq

A Study of Approximate Data Management Techniques for Sensor Networks

Adonis Skordylis
2006 2006 International Workshop on Intelligent Solutions in Embedded Systems  
Recent developments in sensor network technology have enabled the instrumentation of the physical world with smart devices for monitoring purposes.  ...  In this paper, we survey approximate data management techniques for sensor networks that exploit the tolerance of most applications to small inaccuracies in the reported data in order to extend the network  ...  They propose a framework for selecting approximate data with bounded-loss guarantees, while minimizing communication costs throughout the network.  ... 
doi:10.1109/wises.2006.237157 fatcat:ggs3mikolneerev7et4gextwcu

Query Scheduling in the Presence of Complex User Profiles [article]

Haggai Roitman, Avigdor Gal, Louiqa Raschid
2019 arXiv   pre-print
sources.  ...  We present three heuristic solutions for the online problem of query scheduling to satisfy complex user profiles.  ...  As α increases, there is less random selection of resources in each profile, with more execution intervals coming from popular resources.  ... 
arXiv:1902.10384v1 fatcat:2wlld7lydfcl7ghixcg35dogj4

A Study of Approximate Data Management Techniques for Sensor Networks

Adonis Skordylis, Niki Trigoni, Alexandre Guitton
2006 2006 International Workshop on Intelligent Solutions in Embedded Systems  
Recent developments in sensor network technology have enabled the instrumentation of the physical world with smart devices for monitoring purposes.  ...  In this paper, we survey approximate data management techniques for sensor networks that exploit the tolerance of most applications to small inaccuracies in the reported data in order to extend the network  ...  They propose a framework for selecting approximate data with bounded-loss guarantees, while minimizing communication costs throughout the network.  ... 
doi:10.1109/wises.2006.329119 dblp:conf/wises/SkordylisTG06 fatcat:ay3klpfembarrguz7oi2ktdysq

Optimal Policy of Data Dissemination in CDNs

Gadiraju Mahesh, Vatsavayi Valli Kumari
2013 International Journal of Computer Applications  
Continuous aggregate query is a query with aggregation operations and is repeatedly requested by the user.  ...  graph, data aggregator (DA), data incoherency bound.  ...  Engineering College for giving us financial support.  ... 
doi:10.5120/12835-0072 fatcat:cdassklmqzexxikp7i7tentrnu

Approximate Query Processing: What is New and Where to Go?

Kaiyu Li, Guoliang Li
2018 Data Science and Engineering  
To alleviate this problem, approximate query processing (AQP) has been proposed, which aims to find an approximate answer as close as to the exact answer efficiently.  ...  Existing AQP techniques can be broadly categorized into two categories. (1) Online aggregation: select samples online and use these samples to answer OLAP queries. (2) Offline synopses generation: generate  ...  Bounded Resources Approximate query processing with bounded resources mean that the storage or memory is limited so that only a limited number of records can be used to approximately answer the query.  ... 
doi:10.1007/s41019-018-0074-4 fatcat:nhkxz345sfhw7byebh5b7hv3my
« Previous Showing results 1 — 15 out of 57,510 results