A Query Model to Capture Event Pattern Matching in RDF Stream Processing Query Languages

AbstractWe propose a denotational semantic framework for deterministic dataflow and stream processing that encompasses a variety of existing streaming models. Our proposal is based on the idea that data streams, stream transformations, and stream-processing programs should be classified using types. The type of a data stream is captured formally by a monoid, an algebraic structure with a distinguished binary operation and a unit. The elements of a monoid model the finite fragments of a stream, the binary operation represents the concatenation of stream fragments, and the unit is the empty fragment. Stream transformations are modeled using monotone functions on streams, which we call stream transductions. These functions can be implemented using abstract machines with a potentially infinite state space, which we call stream transducers. This abstract typed framework of stream transductions and transducers can be used to (1) verify the correctness of streaming computations, that is, that an implementation adheres to the desired behavior, (2) prove the soundness of optimizing transformations, e.g. for parallelization and distribution, and (3) inform the design of programming models and query languages for stream processing. In particular, we show that several useful combinators can be supported by the full class of stream transductions and transducers: serial composition, parallel composition, and feedback composition.

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XKFitler

International Journal of Information Retrieval Research ◽

10.4018/ijirr.2011010101 ◽

2011 ◽

Vol 1 (1) ◽

pp. 1-18 ◽

Cited By ~ 1

Author(s):

Weidong Yang ◽

Fei Fang ◽

Nan Li ◽

Zhongyu (Joan) Lu

Keyword(s):

Common Ancestor ◽

Keyword Search ◽

Stream Processing ◽

Query Languages ◽

Information Discovery ◽

Text Documents ◽

Filter System ◽

Lowest Common Ancestor ◽

Xml Stream ◽

User Friendly

Most existing XML stream processing systems adopt full structured query languages, such as XPath or XQuery, but they are difficult for ordinary users to learn and use. Keyword search is a user-friendly information discovery technique that has been extensively studied for text documents. This paper presents an XML stream filter system called XKFitler, which is the first system for supporting keyword search over XML stream. In XKFitler, the concepts of XLCA (eXclusive Lowest Common Ancestor) and XLCA Connecting Tree (XLCACT) are used to define the search semantic and results of keywords, and present an approach to filter XML stream according to keywords. The prototype XKFilter is implemented in the experiments.

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XKFilter

Information Retrieval Methods for Multidisciplinary Applications ◽

10.4018/978-1-4666-3898-3.ch001 ◽

2013 ◽

pp. 1-18

Author(s):

Weidong Yang ◽

Fei Fang ◽

Nan Li ◽

Zhongyu (Joan) Lu

Keyword(s):

Common Ancestor ◽

Keyword Search ◽

Stream Processing ◽

Query Languages ◽

Information Discovery ◽

Text Documents ◽

Filter System ◽

Lowest Common Ancestor ◽

Xml Stream ◽

User Friendly

Most existing XML stream processing systems adopt full structured query languages, such as XPath or XQuery, but they are difficult for ordinary users to learn and use. Keyword search is a user-friendly information discovery technique that has been extensively studied for text documents. This paper presents an XML stream filter system called XKFilter, which is the first system for supporting keyword search over XML stream. In XKFilter, the concepts of XLCA (eXclusive Lowest Common Ancestor) and XLCA Connecting Tree (XLCACT) are used to define the search semantic and results of keywords, and present an approach to filter XML stream according to keywords. The prototype XKFilter is implemented in the experiments.

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RSP-QL Semantics

International Journal on Semantic Web and Information Systems ◽

10.4018/ijswis.2014100102 ◽

2014 ◽

Vol 10 (4) ◽

pp. 17-44 ◽

Cited By ~ 38

Author(s):

Daniele Dell'Aglio ◽

Emanuele Della Valle ◽

Jean-Paul Calbimonte ◽

Oscar Corcho

Keyword(s):

Data Streams ◽

Operational Semantics ◽

Stream Processing ◽

Query Languages ◽

Continuous Query ◽

Comprehensive Model ◽

Continuous Processing ◽

Data Interchange ◽

The Web

RDF and SPARQL are established standards for data interchange and querying on the Web. While they have been shown to be useful and applicable in many scenarios, they are not sufficiently adequate for dealing with streams of data and their intrinsic continuous nature. In the last years data and query languages have been proposed to extend both RDF and SPARQL for streams and continuous processing, under the name of RDF Stream Processing – RSP. These efforts resulted in several models and implementations that, at a first look, appear to propose alternative syntaxes but equivalent semantics. However, when asked to continuously answer the same queries on the same data streams, they provide different answers at disparate moments due to the heterogeneity of their operational semantics. These discrepancies render the process of understanding and comparing continuous query results complex and misleading. In this work, the authors propose RSP-QL, a comprehensive model that formally defines the semantics of an RSP system. RSP-QL makes explicit the hidden assumptions of currently available RSP systems, allows defining a formal notion of correctness for RSP query results and, thus, explains why available implementations provide different answers at disparate moments.

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A semantic-syntax model for XML query construction

International Journal of Web Information Systems ◽

10.1108/ijwis-06-2016-0034 ◽

2017 ◽

Vol 13 (2) ◽

pp. 155-172 ◽

Cited By ~ 1

Author(s):

Keng Hoon Gan ◽

Keat Keong Phang

Keyword(s):

Information Needs ◽

Query Language ◽

Query Languages ◽

Target Language ◽

Lower Percentage ◽

Content Type ◽

Semantic Query ◽

Query Structure ◽

Information Requests ◽

Query Model

Purpose When accessing structured contents in XML form, information requests are formulated in the form of special query languages such as NEXI, Xquery, etc. However, it is not easy for end users to compose such information requests using these special queries because of their complexities. Hence, the purpose of this paper is to automate the construction of such queries from common query like keywords or form-based queries. Design/methodology/approach In this paper, the authors address the problem of constructing queries for XML retrieval by proposing a semantic-syntax query model that can be used to construct different types of structured queries. First, a generic query structure known as semantic query structure is designed to store query contents given by user. Then, generation of a target language is carried out by mapping the contents in semantic query structure to query syntax templates stored in knowledge base. Findings Evaluations were carried out based on how well information needs are captured and transformed into a target query language. In summary, the proposed model is able to express information needs specified using query like NEXI. Xquery records a lower percentage because of its language complexity. The authors also achieve satisfactory query construction rate with an example-based method, i.e. 86 per cent (for NEXI IMDB topics) and 87 per cent (NEXI Wiki topics), respectively, compare to benchmark of 78 per cent by Sumita and Iida in language translation. Originality/value The proposed semantic-syntax query model allows flexibility of accommodating new query language by separating the semantic of query from its syntax.

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FastPM: An approach to pattern matching via distributed stream processing

Information Sciences ◽

10.1016/j.ins.2018.04.031 ◽

2018 ◽

Vol 453 ◽

pp. 263-280 ◽

Cited By ~ 3

Author(s):

Dingyu Yang ◽

Jianmei Guo ◽

Zhi-Jie Wang ◽

Yuan Wang ◽

Jingsong Zhang ◽

...

Keyword(s):

Pattern Matching ◽

Stream Processing ◽

Distributed Stream Processing

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Measurement Invariance for Behavioral Observational Measures: The Use of Regression Discontinuity Design and Pattern Matching

PsycEXTRA Dataset ◽

10.1037/e500122015-139 ◽

2014 ◽

Author(s):

L. Ciciolla ◽

S. G. West ◽

B. Keller ◽

K. A. Crnic

Keyword(s):

Measurement Invariance ◽

Pattern Matching ◽

Regression Discontinuity ◽

Regression Discontinuity Design ◽

Observational Measures

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Classification of means and methods of the Web semantic retrieval

PROBLEMS IN PROGRAMMING ◽

10.15407/pp2017.01.030 ◽

2017 ◽

pp. 030-050

Author(s):

J.V. Rogushina ◽

Keyword(s):

Search Engines ◽

Domain Knowledge ◽

Information Needs ◽

Web Search ◽

User Interaction ◽

Query Languages ◽

Semantic Search ◽

Semantic Retrieval ◽

The Web

Problems associated with the improve ment of information retrieval for open environment are considered and the need for it’s semantization is grounded. Thecurrent state and prospects of development of semantic search engines that are focused on the Web information resources processing are analysed, the criteria for the classification of such systems are reviewed. In this analysis the significant attention is paid to the semantic search use of ontologies that contain knowledge about the subject area and the search users. The sources of ontological knowledge and methods of their processing for the improvement of the search procedures are considered. Examples of semantic search systems that use structured query languages (eg, SPARQL), lists of keywords and queries in natural language are proposed. Such criteria for the classification of semantic search engines like architecture, coupling, transparency, user context, modification requests, ontology structure, etc. are considered. Different ways of support of semantic and otology based modification of user queries that improve the completeness and accuracy of the search are analyzed. On base of analysis of the properties of existing semantic search engines in terms of these criteria, the areas for further improvement of these systems are selected: the development of metasearch systems, semantic modification of user requests, the determination of an user-acceptable transparency level of the search procedures, flexibility of domain knowledge management tools, increasing productivity and scalability. In addition, the development of means of semantic Web search needs in use of some external knowledge base which contains knowledge about the domain of user information needs, and in providing the users with the ability to independent selection of knowledge that is used in the search process. There is necessary to take into account the history of user interaction with the retrieval system and the search context for personalization of the query results and their ordering in accordance with the user information needs. All these aspects were taken into account in the design and implementation of semantic search engine "MAIPS" that is based on an ontological model of users and resources cooperation into the Web.

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