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A Boolean query processing with a result cache in mediator systems

Jae-Heon Cheong, Sang-Goo Lee
Proceedings IEEE Advances in Digital Libraries 2000  
In this paper, we propose a new method to efficiently process general Boolean queries using a result cache for mediator systems.  ...  Existing mediator systems employ a result cache that is composed of the results of previously issued queries to reduce this transmission time.  ...  A query optimization method is proposed in [3] , which uses cached queries in a mediator system named HERMES.  ... 
doi:10.1109/adl.2000.848392 dblp:conf/adl/CheongL00 fatcat:7tcswl5tdjhpjl5wbjkbln7hmy

Semantic cache mechanism for heterogeneous Web querying

Boris Chidlovskii, Claudia Roncancio, Marie-Luise Schneider
1999 Computer Networks  
In Web-based searching systems that access distributed information providers, efficient query processing requires an advanced caching mechanism to reduce the query response time.  ...  We also report results of experiments and show how the caching mechanism is implemented in the Knowledge Broker system.  ...  Julliard for useful discussions and large support of the semantic cache implementation in the Knowledge Broker meta-searcher.  ... 
doi:10.1016/s1389-1286(99)00035-3 fatcat:tz2tkx7vhrb73a4g3m4qgbqbzi

Semantic Cache Reasoners [chapter]

Muhammad Azeem, Muhammad Abdul, Muhammad Tanvir
2012 Semantics - Advances in Theories and Mathematical Models  
Ishtique Ahmad for providing help on XML based semantic cache, Mr. Tariq Ali for DL based subsumption analysis, and Mr. Munir Ahmed for providing useful feedbacks.  ...  However, searching performed over web resources through Boolean queries (keywords conjunction with AND & NOT operators) do not work in a plain page caching system.  ...  Semantic cache query processing In general research a semantic cache system can be grouped into two parts i) cache management and ii) query processing.  ... 
doi:10.5772/38864 fatcat:2nlxwnuy2zec5iejsinqvs47ra

OGSA-WebDB: an OGSA-based system for bringing Web databases into the grid

S.M. Pahlevi, I. Kojima
2004 International Conference on Information Technology: Coding and Computing, 2004. Proceedings. ITCC 2004.  
The mediator processes the SQL query in parallel, taking into account the characteristics of the web databases.  ...  Experimental results revealed that the query processing time is so small that it can be ignored for timing considerations.  ...  The result of the mediator processing time is almost the same with that obtained in the previous experiments so we omitted it.  ... 
doi:10.1109/itcc.2004.1286598 dblp:conf/itcc/PahleviK04 fatcat:qz7wchpwsvgwrjzlbeqxbwlmiu

Incorporating Semantic Knowledge into Dynamic Data Processing for Smart Power Grids [chapter]

Qunzhi Zhou, Yogesh Simmhan, Viktor Prasanna
2012 Lecture Notes in Computer Science  
In this paper, we combine semantic web and complex event processing for stream based semantic querying.  ...  Emerging applications in Cyber Physical Systems such as Smart Power Grids that require continuous information monitoring and integration present novel opportunities and challenges for Semantic Web technologies  ...  [17] describes the use of semantic cache in an ontology-based web mediator system and considers extracting partial results from caches for new queries.  ... 
doi:10.1007/978-3-642-35173-0_17 fatcat:wfcsba2p7rcdrpv4cywtzvhrym

Integrating Learning Object Repositories Using a Mediator Architecture [chapter]

Philipp Kärger, Carsten Ullrich, Erica Melis
2006 Lecture Notes in Computer Science  
A mediating component accepts queries formulated in a uniform query language, translates them into repository specific queries and passes them to each connected repository.  ...  We propose a mediator architecture that allows a learning system to retrieve learning objects from heterogeneous repositories.  ...  This research was carried out in the context of the LeActiveMath project, funded under the 6th Framework Program of the European Community -(Contract No. IST-2003-507826).  ... 
doi:10.1007/11876663_16 fatcat:yjxx7foehjaubn4nuc37wgx2rq

A transaction log analysis of a digital library

Steve Jones, Sally Jo Cunningham, Rodger McNab, Stefan Boddie
2000 International Journal on Digital Libraries  
The documents are displayed in order of decreasing similarity. The retrieval system used by the NZDL is MG [34] . A Boolean query can contain operators & (intersection), | (union) and !  ...  As experimental digital library testbeds gain wider acceptance and develop significant user bases, it becomes important to investigate the ways in which users interact with the systems in practice.  ...  In the case of Boolean queries, a small set of cached results can not produce an exhaustive result list for multiple-term queries.  ... 
doi:10.1007/s007999900022 fatcat:sycsbhtl4jbxpiftefatryfzcm

XML queries and algebra in the Enosys integration platform

Yannis Papakonstantinou, Vinayak Borkar, Maxim Orgiyan, Kostas Stathatos, Lucian Suta, Vasilis Vassalos, Pavel Velikhov
2003 Data & Knowledge Engineering  
Section 4 presents the architecture of the mediator query processor and introduces the reader to the role of the algebra in the mediator's query processing.  ...  Query plan composition and query plan decomposition challenges are faced in this process.  ...  In particular, the mediator server process (depending upon appropriate con¯guration by the client) may only send parts of a query result to the client process.  ... 
doi:10.1016/s0169-023x(02)00141-6 fatcat:t4cmezfmn5evppjzrs7a4tcw24

Model analysis for business event processing

L. Zeng, H. Lei, T. Koyanagi, H. Ohsaki, H. Chang
2007 IBM Systems Journal  
This result verifies the effectiveness of the cache and confirms ZENG ET AL 82 5 as aE Without Cache With Cache 82.1 Event/Sec 49 Ee @ High-End Database System 2.2 ee 2 Low-End Database System i a Without  ...  Scheduler With Scheduler VU i) WY a _ c o > Ww CPUs per System Figure 4 ie J Conventional Queuing Approach Network Event/Sec CPUs per System rs) ro) Event/Sec Experimental results: (A) model-driven cache  ... 
doi:10.1147/sj.464.0817 fatcat:sift3ri4o5clbovmgh2vtvgow4


Lionel Savary, Georges Gardarin, Karine Zeitouni
2007 International Journal of Data Warehousing and Mining  
Depending on the size of the target geographical data and the number and complexity of operators in a query, the processing time may quickly become prohibitive.  ...  To optimize spatial queries over GML encoded data, this chapter introduces a novel cache-based architecture. A new cache replacement policy is then proposed.  ...  A Boolean value defined at line 00 indicates if all counters of a query result have no reference.  ... 
doi:10.4018/jdwm.2007010104 fatcat:6tsrcplpazhpfp26cpjudjysee

Transaction processing on confidential data using cipherbase

Arvind Arasu, Ken Eguro, Manas Joglekar, Raghav Kaushik, Donald Kossmann, Ravi Ramamurthy
2015 2015 IEEE 31st International Conference on Data Engineering  
Cipherbase is based on a novel architecture that combines an industrial strength database engine (SQL Server) with lightweight processing over encrypted data that is performed in secure hardware.  ...  This paper presents a prototype of Cipherbase that uses FPGAs to provide secure processing and describes the system engineering details implemented to achieve competitive performance for transactional  ...  CryptDB is a recent system that relies purely on PHE for query processing [3] .  ... 
doi:10.1109/icde.2015.7113304 dblp:conf/icde/ArasuEJKKR15 fatcat:maw45dh4kvhjxhrgkaqm4zto6i

On Z39.50 wrapping and description logics

Yannis Velegrakis, Vassilis Christophides, Panos Constantopoulos
2000 International Journal on Digital Libraries  
Z39.50 is a client/server protocol widely used in digital libraries and museums for searching and retrieving information spread over a number of heterogeneous sources.  ...  In this paper, we propose a description logic (DL) based toolkit for the declarative specification of Z39.50 wrappers.  ...  We also thank 13 A. Analyti, D. Plexousakis, Y. Tzitzikas, and M. Döerr for helpful comments on preliminary versions of this paper.  ... 
doi:10.1007/s007990000036 fatcat:jlz6tundjvdc3a7zfylxzavqj4

Querying over Federated SPARQL Endpoints ---A State of the Art Survey [article]

Nur Aini Rakhmawati and Jürgen Umbrich and Marcel Karnstedt and Ali Hasnain and Michael Hausenblas
2013 arXiv   pre-print
In this paper, we initially give an overview of the federation framework infrastructure and then proceed with a comparison of existing SPARQL federation frameworks.  ...  SPARQL is the standardised query language for RDF, the default data model used in Linked Data deployments and SPARQL Endpoints are a popular access mechanism provided by many Linked Open Data (LOD) repositories  ...  The source selection is done by sending SPARQL ASK queries. The result of a SPARQL ASK query is stored in a cache to reduce communication for successive query.  ... 
arXiv:1306.1723v1 fatcat:u52yefhk2fgtnlbcbk33jsl72y

Query Processing and Optimization on the Web

Mourad Ouzzani, Athman Bouguettaya
2004 Distributed and parallel databases  
In this paper, we survey the current research on fundamental problems to efficiently process queries over Web data integration systems.  ...  Uniformly querying those information sources has been extensively investigated. A major challenge relates to query optimization.  ...  Non-leaf nodes represent Boolean connectors ∧ and ∨. Mediator query plans are represented by query trees.  ... 
doi:10.1023/b:dapd.0000018574.71588.06 fatcat:qmdqsvtmhzhbpk5atffbwa2msu

KOMET — A system for the integration of heterogeneous information sources [chapter]

J. Calmet, S. Jekutsch, P. Kullmann, J. Schü
1997 Lecture Notes in Computer Science  
In combination with an extensible type system and the embedding of external knowledge sources as constraint domains, our mediation language o ers a rich framework, which not only facilitates access to  ...  It is based on the idea of a mediator, which is an independent software layer between an application and various knowledge sources which need to be accessed.  ...  The Subgoal Result Cache is used for tabulation during the resolution process. A bu ering strategy keeps query results across queries if suitable.  ... 
doi:10.1007/3-540-63614-5_31 fatcat:cuv3myek6fgf5cl75jfe43q7zy
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