DOCSLIB.ORG

Feature Grammar Systems

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Feature Grammar Systems Feature Grammar Systems Incremental Maintenance of Indexes to Digital Media Warehouses Menzo Windhouwer ... van M voor M :-) Feature Grammar Systems Incremental Maintenance of Indexes to Digital Media Warehouses ACADEMISCH PROEFSCHRIFT ter verkrijging van de graad van doctor aan de Universiteit van Amsterdam, op gezag van de Rector Magnificus prof. mr. P. F. van der Heijden ten overstaan van een door het college voor promoties ingestelde commissie in het openbaar te verdedigen in de Aula der Universiteit op donderdag 6 november 2003, te 14.00 uur door Menzo Aart Windhouwer geboren te Apeldoorn Promotiecommissie Promotor: prof. dr M. L. Kersten Overige commissieleden: prof. dr P. M. G. Apers prof. dr P. M. E. de Bra prof. dr P. van Emde Boas prof. dr P. Klint Faculteit Faculteit der Natuurwetenschappen, Wiskunde en Informatica Universiteit van Amsterdam The research reported in this thesis was carried out at CWI, the Dutch national research laboratory for mathematics and computer science, within the theme Data Mining and Knowledge Discovery, a subdivision of the research cluster Information Systems. SIKS Dissertation Series No-2003-16. The research reported in this thesis has been carried out under the auspices of SIKS, the Dutch Graduate School for Information and Knowledge Systems. The research and implementation effort reported in this thesis was carried out within the Advanced Multimedia Indexing and Searching, Digital Media Warehouses and Waterland projects. ISBN 90 6196 522 5 Cover design and photography by Dick Windhouwer (www.windhouwer.nl). Contents 1 Digital Media Warehouses 1 1.1 Multimedia Information Retrieval ................... 2 1.2 Annotations ............................... 4 1.2.1 The Semantic Gap ....................... 4 1.2.2 Annotation Extraction Algorithms ............... 5 1.2.3 Annotation Extraction Dependencies ............. 6 1.2.4 Annotation Maintenance .................... 7 1.3 The Acoi System ............................ 8 1.3.1 A Grammar-based Approach .................. 8 1.3.2 System Architecture ...................... 9 1.3.3 Case Studies .......................... 10 1.3.3.1 The WWW Multimedia Search Engine ....... 10 1.3.3.2 The Australian Open Search Engine ........ 11 1.3.3.3 Rijksmuseum Presentation Generation ....... 11 1.4 Discussion ................................ 12 2 Feature Grammar Systems 13 2.1 A Grammar Primer ........................... 15 2.1.1 A Formal Specification of Languages and Grammars ..... 15 2.1.1.1 The Chomsky Hierarchy ............... 16 2.1.1.2 Mild Context-sensitivity ............... 17 2.1.2 The Derivation Process ..................... 18 2.1.2.1 Bidirectional Grammars ............... 19 2.1.2.2 Parse Trees ...................... 19 2.1.2.3 The Delta Operation ................. 19 2.1.2.4 Parse Forests ..................... 20 2.1.2.5 Disambiguation ................... 21 2.1.3 Regulated Rewriting ...................... 21 2.1.3.1 Conditional Grammars ............... 22 2.1.3.2 Tree-controlled Grammars ............. 22 2.1.4 Grammar Systems ....................... 24 vi Contents 2.1.4.1 CD Grammar Systems ................ 24 2.1.4.2 Internal Control ................... 26 2.2 Feature Grammar Systems ....................... 27 2.2.1 Detectors ............................ 28 2.2.2 Atoms .............................. 32 2.2.3 Dependencies .......................... 33 2.2.3.1 Detector Input .................... 33 2.2.3.2 Detector Output ................... 37 2.2.4 Ambiguous Feature Grammar Systems ............ 39 2.2.5 Mildly Context-sensitive Feature Grammar Systems ..... 41 2.3 Discussion ................................ 42 3 Feature Grammar Language 45 3.1 The Basic Feature Grammar Language ................. 45 3.1.1 Production Rules ........................ 46 3.1.2 Atoms .............................. 48 3.1.3 Detectors ............................ 49 3.1.3.1 The XPath Language ................ 50 3.1.3.2 Detector Confidence ................. 52 3.1.4 The Start Symbol ........................ 52 3.2 The Extended Feature Grammar Language ............... 53 3.2.1 Production Rules ........................ 53 3.2.1.1 Additional Sequence Types ............. 53 3.2.1.2 Constants ...................... 54 3.2.2 Detectors ............................ 54 3.2.2.1 Whitebox Detectors ................. 54 3.2.2.2 Plugins ........................ 56 3.2.2.3 Classifiers ...................... 57 3.2.3 The Start Symbol ........................ 58 3.2.3.1 References ...................... 58 3.2.4 Feature Grammar Modules ................... 61 3.2.5 Change Detection ........................ 62 3.3 Discussion ................................ 63 4 Feature Detector Engine 65 4.1 A Parser Primer ............................. 66 4.1.1 More Parsing Algorithms for Context-free Grammars ..... 69 4.2 Parsing Feature Grammar Systems ................... 73 4.2.1 Exhaustive Backtracking for Feature Grammar Systems ... 75 4.2.1.1 Left-recursion .................... 78 4.2.1.2 Lookahead ...................... 80 4.2.1.3 Memoization ..................... 81 4.3 The Feature Detector Engine ...................... 82 vii 4.3.1 The Symbol Table ....................... 84 4.3.1.1 Rewriting ...................... 84 4.3.1.2 Semantic Checks .................. 85 4.3.2 The Parser ........................... 86 4.3.3 The Parse Forest ........................ 86 4.3.3.1 XML and DOM ................... 86 4.3.3.2 Labeling Parse Trees ................. 88 4.3.3.3 Memoized Parse Trees ................ 90 4.3.4 The Sentences ......................... 92 4.3.5 Detectors ............................ 93 4.3.5.1 Detector Input .................... 93 4.3.5.2 Blackbox Detectors ................. 94 4.3.5.3 Plugins ........................ 94 4.3.5.4 Classifiers ...................... 95 4.3.5.5 Start Symbols and References ............ 95 4.3.5.6 Deadlock Resolution ................ 96 4.4 Discussion ................................ 97 5 Feature Databases 99 5.1 The Monet Database Kernel ...................... 99 5.1.1 Monet and XML ........................ 100 5.1.1.1 Semistructured Data ................. 100 5.1.1.2 Monet XML and XMark .............. 101 5.1.1.3 XQuery ....................... 102 5.2 A Feature Database ........................... 102 5.2.1 A Database Schema ...................... 103 5.2.2 A parse forest XML document ................. 105 5.2.3 Inserting a Parse Forest ..................... 107 5.2.4 Replacing a (Partial) Parse Forest ............... 107 5.2.5 Query Facilities ......................... 108 5.2.6 Adding Database Management to a Database Kernel ..... 109 5.3 Discussion ................................ 110 6 Feature Detector Scheduler 111 6.1 The Dependency Graph ......................... 111 6.2 Identifying Change ........................... 114 6.2.1 External Changes ........................ 114 6.2.2 Internal Changes ........................ 115 6.2.2.1 The Start Condition ................. 115 6.2.2.2 The Detector Function ................ 115 6.2.2.3 The Stop Condition ................. 116 6.3 Managing Change ............................ 116 6.3.1 The (Re)validation Process ................... 117 viii Contents 6.3.2 Lookup Table Management .................. 117 6.4 Discussion ................................ 118 7 Case Studies 119 7.1 The Acoi Implementation ........................ 119 7.1.1 Acoi Prehistory ......................... 119 7.1.2 The Acoi Project ........................ 120 7.1.3 Acoi 1998 ............................ 120 7.1.4 Acoi 2000 ............................ 120 7.1.5 Acoi 2002 ............................ 121 7.1.6 Acoi Future ........................... 122 7.2 The WWW Multimedia Search Engine ................. 123 7.2.1 The Feature Grammars ..................... 123 7.2.2 The System Architecture .................... 124 7.2.3 Lessons Learned ........................ 125 7.3 The Australian Open Search Engine .................. 126 7.3.1 The Webspace Method ..................... 127 7.3.2 COBRA ............................. 128 7.3.3 The Australian Open DMW Demonstrator ........... 128 7.3.4 Lessons Learned ........................ 132 7.4 Rijksmuseum Presentation Generation ................. 133 7.4.1 The Style Repository ...................... 133 7.4.2 The Data Repository ...................... 135 7.4.3 The Presentation Environment ................. 136 7.4.4 A Style Feature Grammar ................... 137 7.4.5 Generating the Presentation .................. 139 7.4.6 Lessons Learned ........................ 141 7.5 Discussion ................................ 142 8 Conclusion and Future Work 143 8.1 Conclusion ............................... 143 8.2 Future Work ............................... 144 8.2.1 Feature Grammar Systems ................... 144 8.2.2 Feature Grammar Language .................. 144 8.2.3 Feature Detector Engine .................... 145 8.2.4 Feature Database ........................ 145 8.2.5 Feature Detector Scheduler ................... 145 8.2.6 Digital Media Warehouses ................... 146 8.3 Discussion ................................ 146 A The Feature Grammar Language 147 ix B Feature Grammars 151 B.1 The WWW Feature Grammar ..................... 151 B.2 The Text Feature Grammar ....................... 151 B.3 The HTML Feature Grammar ..................... 152 B.4 The Image Feature Grammar ...................... 153 B.5 The Audio Feature Grammar ...................... 153 B.6 The MIDI Feature Grammar ...................... 154 B.7 The MP3 Feature Grammar ....................... 154 B.8 The Video Feature
Load more

Recommended publications
  • A Geometric Hierarchy Beyond Context-Free Languages*
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Theoretical Computer Science 104 (1992) 235-261 235 Elsevier A geometric hierarchy beyond context-free languages* David J. Weir School of Cognitive and Computing Science, University of Sussex, Falmer. Brighton BNI 9QH, UK Communicated by M.A. Harrison Received October 1990 Revised March 1991 Abstract Weir, D.J., A geometric hierarchy beyond context-free languages, Theoretical Computer Science 104 (1992) 235-261. This paper defines a geometric hierarchy of language classes the first member of which is context-free languages. This hierarchy generalizes the difference between context-free languages and the class of languages generated by four weakly equivalent grammar formalisms that are of interest to computa- tional linguists. A grammatical characterization of the hierarchy is given using a variant of control grammars. Each member of the progression is shown to share many of the attractive features of context-free grammars, in particular, we show that each member is an abstract family of languages. We give a progression of automata and show that it corresponds exactly to the language hierarchy defined with control grammars. 1. Introduction Recent work in computational linguistics suggests that more generative capacity than context-free grammars (CFG) is required to describe natural languages [14, 31. This has led to increased interest in grammar formalisms that are able to provide this additional power without sacrificing the attractive features of context-free languages (CFL) such as polynomial recognition, and various closure and decidability proper- ties. Several formalisms have been independently proposed as being suitable in this regard and it has been shown that the same class of languages is generated by four of these formalisms [19,22, 18,211.
    [Show full text]
  • Parsing Based on N-Path Tree-Controlled Grammars
    Theoretical and Applied Informatics ISSN 1896–5334 Vol.23 (2011), no. 3-4 pp. 213–228 DOI: 10.2478/v10179-011-0015-7 Parsing Based on n-Path Tree-Controlled Grammars MARTIN Cˇ ERMÁK,JIR͡ KOUTNÝ,ALEXANDER MEDUNA Formal Model Research Group Department of Information Systems Faculty of Information Technology Brno University of Technology Božetechovaˇ 2, 612 66 Brno, Czech Republic icermak, ikoutny, meduna@fit.vutbr.cz Received 15 November 2011, Revised 1 December 2011, Accepted 4 December 2011 Abstract: This paper discusses recently introduced kind of linguistically motivated restriction placed on tree-controlled grammars—context-free grammars with some root-to-leaf paths in their derivation trees restricted by a control language. We deal with restrictions placed on n ¸ 1 paths controlled by a deter- ministic context–free language, and we recall several basic properties of such a rewriting system. Then, we study the possibilities of corresponding parsing methods working in polynomial time and demonstrate that some non-context-free languages can be generated by this regulated rewriting model. Furthermore, we illustrate the syntax analysis of LL grammars with controlled paths. Finally, we briefly discuss how to base parsing methods on bottom-up syntax–analysis. Keywords: regulated rewriting, derivation tree, tree-controlled grammars, path-controlled grammars, parsing, n-path tree-controlled grammars 1. Introduction The investigation of context-free grammars with restricted derivation trees repre- sents an important trend in today’s formal language theory (see [3], [6], [10], [11], [12], [13] and [15]). In essence, these grammars generate their languages just like ordinary context-free grammars do, but their derivation trees have to satisfy some simple pre- scribed conditions.
    [Show full text]
  • Grammars Controlled by Petri Nets
    CORE Metadata, citation and similar papers at core.ac.uk Provided by The International Islamic University Malaysia Repository ChapterChapter 15 0 Grammars Controlled by Petri Nets J. Dassow, G. Mavlankulov, M. Othman, S. Turaev, M.H. Selamat and R. Stiebe Additional information is available at the end of the chapter http://dx.doi.org/10.5772/50637 1. Introduction Formal language theory, introduced by Noam Chomsky in the 1950s as a tool for a description of natural languages [8–10], has also been widely involved in modeling and investigating phenomena appearing in computer science, artificial intelligence and other related fields because the symbolic representation of a modeled system in the form of strings makes its processes by information processing tools very easy: coding theory, cryptography, computation theory, computational linguistics, natural computing, and many other fields directly use sets of strings for the description and analysis of modeled systems. In formal language theory a model for a phenomenon is usually constructed by representing it as a set of words, i.e., a language over a certain alphabet, and defining a generative mechanism, i.e., a grammar which identifies exactly the words of this set. With respect to the forms of their rules, grammars and their languages are divided into four classes of Chomsky hierarchy: recursively enumerable, context-sensitive, context-free and regular. Context-free grammars are the most investigated type of Chomsky hierarchy which, in addition, have good mathematical properties and are extensively used in many applications of formal languages. However, they cannot cover all aspects which occur in modeling of phenomena.
    [Show full text]
  • Automaten Und Formale Sprachen Allrode (Harz), 27
    HEORIE- TTAG 2011 21. Theorietag Automaten und Formale Sprachen Allrode (Harz), 27. – 29. September 2011 Tagungsband Jürgen Dassow, Bianca Truthe (Hrsg.) Titel: 21. Theorietag „Automaten und Formale Sprachen“, Allrode (Harz), 27. – 29.9.2011, Tagungsband Veröffentlicht durch die Otto-von-Guericke-Universität Magdeburg Fakultät für Informatik Universitätsplatz 2 39106 Magdeburg Herausgegeben von Jürgen Dassow und Bianca Truthe, 2011 Das Copyright liegt bei den Autoren der Beiträge. Vorwort Der Theorietag ist die Jahrestagung der Fachgruppe Automaten und Formale Sprachen der Ge- sellschaft für Informatik. Er wurde vor 20 Jahren in Magdeburg ins Leben gerufen. Seit dem Jahre 1996 wird der Theorietag von einem eintägigen Workshop mit eingeladenen Vorträgen begleitet. Im Laufe des Theorietags findet auch die jährliche Fachgruppensitzung statt. Die bisherigen Theorietage wurden in Magdeburg (1991), in Kiel (1992), auf Schloß Dag- stuhl (1993), in Herrsching bei München (1994 und 2003), auf Schloß Rauischholzhausen (1995), in Cunnersdorf in der Sächsischen Schweiz (1996), in Barnstorf bei Bremen (1997), in Riveris bei Trier (1998), in Schauenburg-Elmshagen bei Kassel (1999), in Wien (2000 und 2006), in Wendgräben bei Magdeburg (2001), in der Lutherstadt Wittenberg (2002 und 2009), in Caputh bei Potsdam (2004), in Lauterbad bei Freudenstadt (2005), in Leipzig (2007), in Wettenberg-Launsbach bei Gießen (2008) und in Baunatal bei Kassel (2010) ausgerichtet. Der diesjährige Theorietag wird nach 1991 und 2001 wieder von der Arbeitsgruppe „For- male Sprachen und Automaten“ der Otto-von-Guericke-Universität Magdeburg organisiert. Er findet mit dem vorangehenden Workshop vom 27. bis 29. September 2011 in Allrode im Harz statt. Auf dem Workshop tragen • Frank Drewes aus Umeå, • Manfred Droste aus Leipzig, • Florin Manea aus Bukarest, • Sergey Verlan aus Paris und • Georg Zetzsche aus Kaiserslautern vor.
    [Show full text]
  • TH`ESE Zhe CHEN the Control System in Formal
    N◦ d'ordre : 1036 THESE` pr´esent´ee`a l'Institut National des Sciences Appliquees´ de Toulouse pour l'obtention du titre de DOCTEUR de l'Universit´ede Toulouse d´elivr´epar l'INSA Sp´ecialit´e:Syst`emesInformatiques par Zhe CHEN Lab. Toulousain de Technologie et d'Ingenierie´ des Systemes` (LATTIS) Laboratoire d'Analyse et d'Architecture des Systemes` (LAAS-CNRS) Ecole´ Doctorale Syst`emes Titre de la th`ese: The Control System in Formal Language Theory and The Model Monitoring Approach for Reliability and Safety Soutenue le 9 Juillet 2010, devant le jury : Rapporteur : Maritta Heisel Professeur `al'Universit¨atDuisburg-Essen, Germany Rapporteur : Fabrice Bouquet Professeur `al'INRIA, Universit´ede Franche-Comt´e Examinateur: Gilles Motet Professeur `al'INSA de Toulouse - Directeur de th`ese Examinateur: Karama Kanoun Directeur de Recherche au LAAS-CNRS Examinateur: Jean-Paul Blanquart Astrium, European Aeronautic Defence and Space (EADS) Acknowledgement Although I have been mostly working independently in the lab during all those years, I would not have been able to do this thesis without the support, advice and encouragement of others, teachers, friends and colleagues. Accordingly, I would like to use this opportunity to express my gratitude to a number of people who over the years have contributed in various ways to the completion of this work. In the first place I would like to record my gratitude to my thesis supervisor Prof. Gilles Motet for guiding me in my research, and at the same time, for letting me the freedom to take initiatives in the development of my lines of research.
    [Show full text]
  • PETRI NET CONTROLLED GRAMMARS Sherzod Turaev ISBN:978-84-693-1536-1/DL:T-644-2010
    UNIVERSITAT ROVIRA I VIRGILI PETRI NET CONTROLLED GRAMMARS Sherzod Turaev ISBN:978-84-693-1536-1/DL:T-644-2010 Facultat de Lletres Departament de Filologies Romàniques Petri Net Controlled Grammars PhD Dissertation Presented by Sherzod Turaev Supervised by Jürgen Dassow Tarragona, 2010 UNIVERSITAT ROVIRA I VIRGILI PETRI NET CONTROLLED GRAMMARS Sherzod Turaev ISBN:978-84-693-1536-1/DL:T-644-2010 Supervisor: Prof. Dr. Jürgen Dassow Fakultät für Informatik Institut für Wissens- und Sprachverarbeitung Otto-von-Guericke-Universität Magdeburg D-39106 Magdeburg, Germany Tutor: Dr. Gemma Bel Enguix Grup de Recerca en Lingüística Matemàtica Facultat de Lletres Universitat Rovira i Virgili Av. Catalunya, 35 43002 Tarragona, Spain UNIVERSITAT ROVIRA I VIRGILI PETRI NET CONTROLLED GRAMMARS Sherzod Turaev ISBN:978-84-693-1536-1/DL:T-644-2010 Acknowledgements It is a pleasure to thank many people who helped me to made this thesis possible. First of all I would like to express my sincere gratitude to my super- visor, Professor Jürgen Dassow. He helped me with his enthusiasm, his inspiration, and his efforts. During the course of this work, he provided with many helpful suggestions, constant encouragement, important advice, good teaching, good company, and lots of good ideas. It has been an honor to work with him. I would like to thank the head of our research group, Professor Car- los Martín-Vide, for his great effort in establishing the wonderful circum- stances of PhD School on Formal Languages and Applications, and for his help in receiving financial support throughout my PhD. This work was made thanks to the financial support of research grant 2006FI-01030 from AGAUR of Catalonia Government.
    [Show full text]
  • Controlled Pure Grammar Systems
    Journal of Universal Computer Science, vol. 18, no. 14 (2012), 2024-2040 submitted: 14/1/12, accepted: 16/4/12, appeared: 28/7/12 © J.UCS Controlled Pure Grammar Systems Alexander Meduna (Brno University of Technology, Faculty of Information Technology IT4Innovations Centre of Excellence, Brno, Czech Republic meduna@fit.vutbr.cz) Petr Zemek (Brno University of Technology, Faculty of Information Technology IT4Innovations Centre of Excellence, Brno, Czech Republic izemek@fit.vutbr.cz) Abstract: This paper discusses grammar systems that have only terminals, work in the leftmost way, and generate their languages under the regulation by control lan- guages over rule labels. It establishes three results concerning their generative power. First, without any control languages, these systems are not even able to generate all context-free languages. Second, with regular control languages, these systems, hav- ing no more than two components, characterize the family of recursively enumerable languages. Finally, with control languages that are themselves generated by regular- controlled context-free grammars, these systems over unary alphabets generate nothing but regular languages. In its introductory section, the paper gives a motivation for in- troducing these systems, and in the concluding section, it formulates several open problems. Key Words: formal languages, pure grammar systems, controlled derivations Category: F.4.2, F.4.3, F.1.1 1 Introduction Indisputably, context-free grammars are central to formal language theory as a whole (see [Rozenberg and Salomaa 1997, Dassow and P˘aun 1989, Meduna 2000, Salomaa 1973]). It thus comes as no surprise that this theory has introduced a broad variety of their modified versions, ranging from simplified and restricted versions up to fundamentally generalized systems based upon these grammars.
    [Show full text]
  • Grammars with Regulated Rewriting
    Grammars with Regulated Rewriting J¨urgen Dassow Otto-von-Guericke-Universit¨atMagdeburg PSF 4120, D – 39016 Magdeburg e-mail: [email protected] Abstract: Context-free grammars are not able to cover all linguistic phenomena. Thus we define some types of grammars where context-free rules are used and restric- tion imposed on the derivations. We illustrate the concepts by example, compare the generative power, give some closure and decidability properties and basic facts on syntactic complexity. 0. Introduction The regular and context-free grammars/languages are the most investigated types of formal languages which, in addition, have a lot of nice properties (see [9, 11, 14] and the corresponding chapters of this volume). However, these types of grammars/languages are not able to cover all aspects which occur in modelling of phenomena by means of formal languages. Here we only mention an example from natural languages. Let us consider the following sequence of a German dialect spoken in Switzerland: S1=Jan s¨aitdas mer em Hans h¨alfed. (Jan says that we helped Hans.) S2=Jan s¨aitdas mer em Hans es Huus h¨alfed aastriche. (Jan said that we helped Hans to paint the house.) S3=Jan s¨aitdas mer d’chind em Hans es Huus l¨ondh¨alfed aastriche. (Jan said that we allowed the children to help Hans to paint the house.) Further, let h be the morphisms which maps Hans and h¨alfed to the letter a, Huus, aastriche, d’chind and l¨ond to b and all other words of the sentences to the empty word.
    [Show full text]
  • Image and Video Searching on the World Wide Web
    Image and Video Searching on the World Wide Web Michael J. Swain Cambridge Research Laboratory Compaq Computer Corporation One Kendall Square, Bldg. 700 Cambridge, MA 02139, USA [email protected] Abstract The proliferation of multimedia on the World Wide Web has led to the introduction of Web search engines for images, video, and audio. On the Web, multimedia is typically embedded within documents that provide a wealth of indexing information. Harsh computational constraints imposed by the economics of advertising-supported searches restrict the complexity of analysis that can be performed at query time. And users may be unwilling to do much more than type a keyword or two to input a query. Therefore, the primary sources of information for indexing multimedia documents are text cues extracted from HTML pages and multimedia document headers. Off-line analysis of the content of multimedia documents can be successfully employed in Web search engines when combined with these other information sources. Content analysis can be used to categorize and summarize multimedia, in addition to providing cues for finding similar documents. This paper was delivered as a keynote address at the Challenge of Image Retrieval ’99. It represents a personal and purposefully selective review of image and video searching on the World Wide Web. 1 Introduction The World Wide Web is full of images, video, and audio, as well as text. Search engines are starting to appear that can allow users to find such multimedia, the quantity of which is growing even faster than text on the Web. As 56 kbps (V.90) modems have become standardized and widely used, and as broadband cable modem and telephone-network based Digital Subscribe Line (DSL) services gain following in the United States and Europe, multimedia on the Web is becoming freed of its major impediment: low-bandwidth consumer Internet connectivity.
    [Show full text]
  • Search Computing Cover.Indd
    Search Computing Business Areas, Research and Socio-Economic Challenges Media Search Cluster White Paper European Commission European SocietyInformation and Media LEGAL NOTICE By the Commission of the European Communities, Information Society & Media Directorate-General, Future and Emerging Technologies units. Neither the European Commission nor any person acting on its behalf is responsible for the use which might be made of the information contained in the present publication. The European Commission is not responsible for the external web sites referred to in the present publication. The views expressed in this publication are those of the authors and do not necessarily reflect the official European Commission view on the subject. Luxembourg: Publications Office of the European Union, 2011 ISBN 978-92-79-18514-4 doi:10.2759/52084 © European Union, July 2011 Reproduction is authorised provided the source is acknowledged. © Cover picture: Alinari 24 ORE, Firenze, Italy Printed in Belgium White paper: Search Computing: Business Areas, Research and Socio-Economic Challenges Search Computing: Business Areas, Research and Socio- Economic Challenges Media Search Cluster White Paper Media Search Cluster - 2011 Page 1 White paper: Search Computing: Business Areas, Research and Socio-Economic Challenges Coordinated by the CHORUS+ project co-funded by the European Commission under - 7th Framework Programme (2007-2013) by the –Networked Media and Search Systems Unit of DG INFSO Media Search Cluster - 2011 Page 2 White paper: Search Computing:
    [Show full text]
  • Error Tolerance for the Recognition of Faulty Strings in a Regulated Grammar Using Fuzzy Sets
    Sådhanå (2018) 43:134 © Indian Academy of Sciences https://doi.org/10.1007/s12046-018-0833-ySadhana(0123456789().,-volV)FT3](0123456789().,-volV) Error tolerance for the recognition of faulty strings in a regulated grammar using fuzzy sets AJAY KUMAR*, NIDHI KALRA and SUNITA GARHWAL Computer Science and Engineering Department, Thapar Institute of Engineering & Technology, Patiala 147004, India e-mail: [email protected] MS received 25 July 2017; revised 5 January 2018; accepted 8 January 2018; published online 10 July 2018 Abstract. To overcome the limitations of context-free and context-sensitive grammars, regulated grammars have been proposed. In this paper, an algorithm is proposed for the recognition of faulty strings in regulated grammar. Furthermore, depending on the errors and certainty, it is decided whether the string belongs to the 2 language or not based on string membership value. The time complexity of the proposed algorithm is O(|GR|·|w|), where |GR| represents the number of production rules and |w| is the length of the input string, w. The reader is provided with numerical examples by applying the algorithm to regularly controlled and matrix grammar. Finally, the proposed algorithm is applied in the Hindi language for the recognition of faulty strings in regulated grammar as a real-life application. Keywords. Fuzzy regulated grammar; fuzzy sets; Chomsky normal form; regularly controlled grammar; matrix grammar. 1. Introduction inference methods [10–12] are used in the design of fuzzy systems. Context-free grammars are not able to cover all aspects of Motivated by the prior work of recognition of imperfect linguistic phenomena. The membership of a string in a strings in context-free grammar [13] and context-sensitive context-sensitive grammar is decided in exponential time.
    [Show full text]
  • Brno University of Technology Regulated Grammars
    BRNO UNIVERSITY OF TECHNOLOGY VYSOKÉ UČENÍ TECHNICKÉ V BRNĚ FACULTY OF INFORMATION TECHNOLOGY DEPARTMENT OF INFORMATION SYSTEMS FAKULTA INFORMAČNÍCH TECHNOLOGIÍ ÚSTAV INFORMAČNÍCH SYSTÉMŮ REGULATED GRAMMARS: CONCEPTS, PROPERTIES AND APPLICATIONS REGULOVANÉ GRAMATIKY: KONCEPTY, VLASTNOSTI A VYUŽITÍ MASTER’S THESIS DIPLOMOVÁ PRÁCE AUTHOR Bc. PETR BEDNÁŘ AUTOR PRÁCE SUPERVISOR Prof. RNDr. ALEXANDER MEDUNA, CSc. VEDOUCÍ PRÁCE BRNO 2016 Abstract This thesis is investigating regulated grammars. Introduces new modifications of existing regulated grammars. Introduces parsing methods of newlz introduces modifications. Dis- cusses problems of determinism in definition of grammars. It studies the expressive strength of these new modifications applied on regular-controlled grammars. Abstrakt Tato práce se zabývá regulovanými gramatikami. Zavádí nové modifikace existujících reg- ulovaných gramatik. Pro tyto modifikace zavádí metody syntaktické analýzi. Diskutuje problémy determinismu v definici gramatik. Studuje sílu nově uvedených modifikací ap- likovaných na regulárně regulované gramatiky. Keywords regulated grammars, determinism, syntax analysis, regular-controlled grammars, LL gram- mars Klíčová slova regulované gramatiky, determinismus, syntaktická analýza, regulárně regulované gramatiky, LL gramatiky Reference BEDNÁŘ, Petr. Regulated Grammars: Concepts, Properties and Applications. Brno, 2016. Master’s thesis. Brno University of Technology, Faculty of Information Technology. Supervisor Meduna Alexander. Regulated Grammars: Concepts, Properties and Applications Declaration Hereby I declare that this master’s thesis was prepared as an original author’s work under the supervision of prof. RNDr. Alexandra Meduny, CSc. All the relevant information sources, which were used during preparation of this thesis, are properly cited and included in the list of references. ....................... Petr Bednář May 25, 2016 Acknowledgements I would like to express my gratitude to my supervisor prof. RNDr.
    [Show full text]