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  • Enriching Unstructured Media Content About Events to Enable Semi-Automated Summaries, Compilations, and Improved Search by Leveraging Social Networks  Open access

     Steiner, Thomas
    Universitat Politècnica de Catalunya
    Theses

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    Enriquiment del contingut desestructurat dels elements multimèdia sobre esdeveniments, per permetre resums semi-automàtics, compilacions i cerques millorades aprofitant les xarxes socials(i) Els dispositius mòbils i les xarxes socials són omnipresentsEls dispositius mòbils com els telèfons intel¿ligents, les tauletes o les càmeres digitals, juntament amb les xarxes socials, permeten als usuaris crear, compartir i consumir enormes quantitats d'elements multimèdia com vídeos o fotos, tant en mobilitat com a casa. Aquests dispositius mòbils¿per pura definició¿acompanyen als seus propietaris independentment d'on estiguin. En conseqüència, els dispositius mòbils són omnipresents en tot tipus d'esdeveniments per capturar els moments notables. Alguns exemples poden ser discursos en conferències, concerts de música als estadis o fins i tot catàstrofes naturals com els terratrèmols que afecten zones o països sencers. En aquests esdeveniments¿sempre que hi hagi una xarxa estable¿serà posible publicar a les xarxes socials una part dels elements multimèdia instantàniament o posteriorment, quan l'esdeveniment en qüestió s'hagi acabat o es tingui novament connexió a la xarxa.(ii) Trobar elements multimèdia representatius per a un esdeveniment és complicatLes operacions de cerca d'elements multimèdia més habituals com, per exemple, buscar el videoclip oficial per un cert disc d'èxit en una plataforma online de vídeo, en el cas més senzill, es pot realitzar basant-se en metadades potencialment inexactes creades manualment, o en altres tècniques més avançades d'anàlisi de contingut com reconeixement òptic de caràcters, reconeixement automàtic de veu, o empremta digital acústica. En canvi, situacions més complexes, com la recuperació de tots els elements multimèdia (o només els més representatius) que s'han creat en un esdeveniment determinat, amb l'objectiu de crear resums o compilacions d'elements multimèdia que cobreixen un esdeveniment determinat, són difícils de realitzar o quasi impossibles de dur a terme a gran escala. Com a resultat, el principal tema de recerca de la present tesi es pot formular de la següent manera.(iii) Problema d'investigació"Es poden crear galeries d'elements multimèdia que resumeixin un esdeveniment concret únicament basades en dades textuals i multimèdia de les xarxes socials?"(iv) AportacionsEn el context d'aquesta tesi, s'ha desenvolupat i avaluat una nova aplicació interactiva i altres mètodes relacionats amb l'enriquiment d'elements multimèdia, aprofitant les xarxes socials, utilitzant la web de dades, les tècniques conegudes de consulta d'imatges mitjançant exemple (CBIR) i consulta de vídeos mitjançant exemple (CBVR), i d'esquemes de direccionament d'elements multimèdia detallats, com l'identificador de fragments d'elements multimèdia per proporcionar una solució escalable i en temps real a la situació esmentada anterioment de resum d'esdeveniments i compilació d'elements multimèdia.

    (i) Mobile devices and social networks are omnipresent Mobile devices such as smartphones, tablets, or digital cameras together with social networks enable people to create, share, and consume enormous amounts of media items like videos or photos both on the road or at home. Such mobile devices "by pure definition" accompany their owners almost wherever they may go. In consequence, mobile devices are omnipresent at all sorts of events to capture noteworthy moments. Exemplary events can be keynote speeches at conferences, music concerts in stadiums, or even natural catastrophes like earthquakes that affect whole areas or countries. At such events" given a stable network connection" part of the event-related media items are published on social networks both as the event happens or afterwards, once a stable network connection has been established again. (ii) Finding representative media items for an event is hard Common media item search operations, for example, searching for the official video clip for a certain hit record on an online video platform can in the simplest case be achieved based on potentially shallow human-generated metadata or based on more profound content analysis techniques like optical character recognition, automatic speech recognition, or acoustic fingerprinting. More advanced scenarios, however, like retrieving all (or just the most representative) media items that were created at a given event with the objective of creating event summaries or media item compilations covering the event in question are hard, if not impossible, to fulfill at large scale. The main research question of this thesis can be formulated as follows. (iii) Research question "Can user-customizable media galleries that summarize given events be created solely based on textual and multimedia data from social networks?" (iv) Contributions In the context of this thesis, we have developed and evaluated a novel interactive application and related methods for media item enrichment, leveraging social networks, utilizing the Web of Data, techniques known from Content-based Image Retrieval (CBIR) and Content-based Video Retrieval (CBVR), and fine-grained media item addressing schemes like Media Fragments URIs to provide a scalable and near realtime solution to realize the abovementioned scenario of event summarization and media item compilation. (v) Methodology For any event with given event title(s), (potentially vague) event location(s), and (arbitrarily fine-grained) event date(s), our approach can be divided in the following six steps. 1) Via the textual search APIs (Application Programming Interfaces) of different social networks, we retrieve a list of potentially event-relevant microposts that either contain media items directly, or that provide links to media items on external media item hosting platforms. 2) Using third-party Natural Language Processing (NLP) tools, we recognize and disambiguate named entities in microposts to predetermine their relevance. 3) We extract the binary media item data from social networks or media item hosting platforms and relate it to the originating microposts. 4) Using CBIR and CBVR techniques, we first deduplicate exact-duplicate and near-duplicate media items and then cluster similar media items. 5) We rank the deduplicated and clustered list of media items and their related microposts according to well-defined ranking criteria. 6) In order to generate interactive and user-customizable media galleries that visually and audially summarize the event in question, we compile the top-n ranked media items and microposts in aesthetically pleasing and functional ways.

  • Algorísmia, Bioinformàtica, Complexitat i Mètodes Formals

     Cortadella Fortuny, Jordi; Orejas Valdes, Fernando; Martinez Parra, Conrado; Serna Iglesias, Maria Jose; Alvarez Faura, Maria Del Carme; Gabarro Valles, Joaquin; Atserias Peri, Albert; Messeguer Peypoch, Xavier; Petit Silvestre, Jordi; Pino Blanco, Elvira Patricia; Roura Ferret, Salvador; Valiente Feruglio, Gabriel Alejandro; Carmona Vargas, Jose; Godoy Balil, Guillermo; Duch Brown, Amalia; Blesa Aguilera, Maria Jose; Molter, Hendrik; De San Pedro Martín, Javier; Muñoz Gama, Jorge; Diaz Cort, Jose Maria
    Competitive project

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  • Modelos y métodos computacionales para datos masivos estructurados

     Diaz Cort, Jose Maria; Cortadella Fortuny, Jordi; Serna Iglesias, Maria Jose; Alvarez Faura, Maria Del Carme; Pino Blanco, Elvira Patricia; Carmona Vargas, Jose; Gabarro Valles, Joaquin; Xhafa Xhafa, Fatos; Pasarella Sanchez, Ana Edelmira; Petit Silvestre, Jordi; Mylonakis Pascual, Nicolas Eduardo; Martinez Parra, Conrado; Duch Brown, Amalia; Godoy Balil, Guillermo; Roura Ferret, Salvador; Roca Perez, Antoni; Soares Ribeiro, Joel Tiago; Pérez Giménez, Xavier; Orejas Valdes, Fernando
    Competitive project

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  • The life cycle of a cutting-edge technology course: A Coaching experience on Android

     Blesa Aguilera, Maria Jose; Duch Brown, Amalia; Gabarro Valles, Joaquin; Serna Iglesias, Maria Jose
    International Conference on Computer Supported Education
    p. 159-166
    DOI: 10.5220/0004841301590166
    Presentation's date: 2014-04
    Presentation of work at congresses

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    What is the role that a university should play in the spreading of cutting-edge technologies? It is argued here that one possibility is to bring focused cutting-edge technology courses in the standard curriculum. It is contended that such courses have shorter life-spans than conventional subjects and, consequently, their implementation needs to be more dynamic. These claims are backed by discussing the life-cycle of an Android course running biannually from Spring 2010 to Spring 2013 at Universitat Politécnica de Catalunya. The rise phase of this course (which lasted two semesters) was a challenging experience that motivated students and lecturers to play a cooperative and active role in the creation of true working Android applications. The course held stable for two semesters while student motivation began to fall as smart phones increasingly became everyday objects. During these two phases the course was offered as extra curricular in the undergraduate phase. Two added factors were instrumental in the decline (or fall) phase: the availability of on-line information and the fact that the course became a requirement of a master's curriculum.

  • Reasoning about orchestrations of web services using partial correctness

     Stewart, Alan; Gabarro Valles, Joaquin; Keenan, Anthony
    Formal aspects of computing
    Vol. 25, num. 6, p. 833-846
    DOI: 10.1007/s00165-011-0212-5
    Date of publication: 2013-11-01
    Journal article

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    A service is a remote computational facility which is made available for general use by means of a wide-area network. Several types of service arise in practice: stateless services, shared state services and services with states which are customised for individual users. A service-based orchestration is a multi-threaded compu- tation which invokes remote services in order to deliver results back to a user (publication). In this paper a means of specifying services and reasoning about the correctness of orchestrations over stateless services is presented. As web services are potentially unreliable the termination of even finite orchestrations cannot be guaranteed. For this reason a partial-correctness powerdomain approach is proposed to capture the semantics of recursive orchestrations.

  • Capturing the functionality of web services with functional descriptions

     Verborgh, Ruben; Steiner, Thomas; De Roo, Jos; Van Deursen, Davy; Van de Walle, Rik; Gabarro Valles, Joaquin
    Multimedia tools and applications
    Vol. 64, num. 2, p. 365-387
    DOI: 10.1007/s11042-012-1004-5
    Date of publication: 2013
    Journal article

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    Many have left their footprints on the field of semantic RESTful Web service description. Albeit some of the propositions are even W3C Recommendations, none of the proposed standards could gain significant adoption with Web service providers. Some approaches were supposedly too complex and verbose, others were considered not RESTful, and some failed to reach a significant majority of API providers for a combination of the reasons above. While we neither have the silver bullet for universal Web service description, with this paper, we want to suggest a lightweight approach called RESTdesc. It expresses the semantics of Web services by pre- and postconditions in simple N3 rules, and integrates existing standards and conventions such as Link headers, HTTP OPTIONS, and URI templates for discovery and interaction. This approach keeps the complexity to a minimum, yet still enables service descriptions with full semantic expressiveness. A sample implementation on the topic of multimedia Web services verifies the effectiveness of our approach.

  • On the hardness of game equivalence under local isomorphism

     Gabarro Valles, Joaquin; Garcia Chacon, Alina; Serna Iglesias, Maria Jose
    RAIRO. Theoretical informatics and applications
    Vol. 47, num. 2, p. 147-169
    DOI: 10.1051/ita/2012024
    Date of publication: 2013-04
    Journal article

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    We introduce a type of isomorphism among strategic games that we call local isomorphism. Local isomorphisms is a weaker version of the notions of strong and weak game isomorphism introduced in [J. Gabarro, A. Garcia and M. Serna, Theor. Comput. Sci. 412 (2011) 6675-6695]. In a local isomorphism it is required to preserve, for any player, the player's preferences on the sets of strategy profiles that differ only in the action selected by this player. We show that the game isomorphism problem for local isomorphism is equivalent to the same problem for strong or weak isomorphism for strategic games given in: general, extensive and formula general form. As a consequence of the results in [J. Gabarro, A. Garcia and M. Serna, Theor. Comput. Sci. 412 (2011) 6675-6695] this implies that local isomorphism problem for strategic games is equivalent to (a) the circuit isomorphism problem for games given in general form, (b) the boolean formula isomorphism problem for formula games in general form, and (c) the graph isomorphism problem for games given in explicit form

  • Adding meaning to social network microposts via multiple named entity disambiguation APIs and tracking their data provenance

     Steiner, Thomas; Verborgh, Ruben; Gabarro Valles, Joaquin; Van de Walle, Rik
    International Journal of Computer Information Systems and Industrial Management Applications
    Vol. 5, p. 69-78
    Date of publication: 2012
    Journal article

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  • Orchestrating unreliable services: strategic and probabilistic approaches to reliability

     Gabarro Valles, Joaquin; Serna Iglesias, Maria Jose; Stewart, Alan
    DOI: 10.1007/978-3-642-30065-3
    Date of publication: 2012
    Book chapter

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  • Functional descriptions as the bridge between hypermedia APIs and the semantic web

     Verborgh, Ruben; Steiner, Thomas; Van Deursen, Davy; Coppens, Sam; Gabarro Valles, Joaquin; Van de Walle, Rik
    International Workshop on RESTful Design
    p. 33-40
    DOI: 10.1145/2307819.2307828
    Presentation's date: 2012-04-17
    Presentation of work at congresses

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  • A social description revolution: describing web APIs' social parameters with RESTdesc

     Verborgh, Ruben; Steiner, Thomas; Gabarro Valles, Joaquin; Mannens, Erik; Van de Walle, Rik
    AAAI Conference on Artificial Intelligence
    p. 81-86
    Presentation's date: 2012
    Presentation of work at congresses

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  • The missing links: how the description format restdesc applies the linked data vision to connect hypermedia apis

     Verborgh, Ruben; Steiner, Thomas; Van de Walle, Rik; Gabarro Valles, Joaquin
    Linked APIs for the Semantic Web: An essential problem in need of a fresh look
    Presentation's date: 2012
    Presentation of work at congresses

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  • Defining aesthetic principles for automatic media gallery layout for visual and audial event summarization based on social networks

     Steiner, Thomas; Verborgh, Ruben; Gabarro Valles, Joaquin; Van de Walle, Rik
    International Workshop on Quality of Multimedia Experience
    p. 27-28
    DOI: 10.1109/QoMEX.2012.6263875
    Presentation's date: 2012
    Presentation of work at congresses

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  • Report on Trends in Theoretical Computer Science: celebrating Josep Diaz 60th birthday

     Alvarez Faura, Maria Del Carme; Blesa Aguilera, Maria Jose; Duch Brown, Amalia; Gabarro Valles, Joaquin; Martinez Parra, Conrado
    Bulletin of the European Association for Theoretical Computer Science
    num. 104, p. 144-148
    Date of publication: 2011-06
    Journal article

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  • Equilibria problems on games: complexity versus succinctness

     Alvarez Faura, Maria Del Carme; Gabarro Valles, Joaquin; Serna Iglesias, Maria Jose
    Journal of computer and system sciences
    Vol. 77, num. 6, p. 1172-1197
    DOI: 10.1016/j.jcss.2011.01.001
    Date of publication: 2011-11
    Journal article

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  • Reunión del TC-1 (Foundations of Computer Science)

     Hinchey, Michael; Breitman, Karin; Gabarro Valles, Joaquin
    Novática: revista de la Asociación de Técnicos de Informática
    Vol. 211, num. mayo-junio, p. 3
    Date of publication: 2011-05-01
    Journal article

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  • The complexity of game isomorphism

     Gabarro Valles, Joaquin; Garcia Chacon, Alina; Serna Iglesias, Maria Jose
    Theoretical computer science
    Vol. 412, num. 48, p. 6675-6695
    DOI: 10.1016/j.tcs.2011.07.022
    Date of publication: 2011-11-11
    Journal article

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  • Web services and Incerta Spiriti: a game theoretic approach to uncertainty

     Gabarro Valles, Joaquin; Serna Iglesias, Maria Jose; Stewart, Alan
    Lecture notes in computer science
    Vol. 6717, p. 651-662
    DOI: 10.1007/978-3-642-22152-1_55
    Date of publication: 2011-06-24
    Journal article

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  • Computational models for networks of tiny artifacts: a survey

     Alvarez Faura, Maria Del Carme; Chatzigiannakis, Ioannis; Duch Brown, Amalia; Gabarro Valles, Joaquin; Michail, Othon; Serna Iglesias, Maria Jose; Spirakis, Paul George
    Computer science review
    Vol. 5, num. 1, p. 7-25
    DOI: 10.1016/j.cosrev.2010.09.001
    Date of publication: 2011
    Journal article

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  • Coaching on new technologies: programming workshop on Android applications for Google phones

     Blesa Aguilera, Maria Jose; Duch Brown, Amalia; Gabarro Valles, Joaquin; Hernández, Hugo; Serna Iglesias, Maria Jose
    Bulletin of the European Association for Theoretical Computer Science
    Vol. 105, p. 204-208
    Date of publication: 2011-10
    Journal article

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    In this work we describe our experience teaching an innovative Android programming workshop organized by the Universitat Politècnica de Catalunya (UPC) within the AndroidEDU Google EMEA Program. The growing interest in Android has allowed us to apply proactive learning techniques with very good results. As teachers, this was a challenging experience, that has forced us to rethink our role, to create educational material accordant with the new communication media (forums, YouTube, etc.), and to supply the lack of expertise with an interesting collaboration between teachers and students. After three semesters teaching this workshop, we are convinced that this is an experience to share since the results have far exceeded our expectations.

  • Computational models for networks of tiny artifacts

     Alvarez Faura, Maria Del Carme; Chatzigiannakis, Ioannis; Duch Brown, Amalia; Gabarro Valles, Joaquin; Michail, Othon; Serna Iglesias, Maria Jose; Spirakis, Paul George
    Date: 2011-01-05
    Report

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  • Taller de programación Android

     Blesa Aguilera, Maria Jose; Duch Brown, Amalia; Gabarro Valles, Joaquin; Pibernat, Heranandez Hugo; Serna Iglesias, Maria Jose
    Novática: revista de la Asociación de Técnicos de Informática
    Vol. 214, p. 47-51
    Date of publication: 2011-11
    Journal article

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    Efficient runtime service discovery and consumption with hyperlinked RESTdesc  Open access

     Verborgh, Ruben; Steiner, Thomas; Van Deursen, Davy; Van de Walle, Rik; Gabarro Valles, Joaquin
    Next Generation Web Services Practices
    p. 373-379
    DOI: 10.1109/NWeSP.2011.6088208
    Presentation's date: 2011-10-20
    Presentation of work at congresses

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    Hyperlinks and forms let humans navigate with ease through websites they have never seen before. In contrast, automated agents can only perform preprogrammed actions on Web services, reducing their generality and restricting their usefulness to a specialized domain. Many of the employed services call themselves RESTful, although they neglect the hypermedia constraint as defined by Roy T. Fielding, stating that the application state should be driven by hypertext. This lack of link usage on the Web of services severely limits agents in what they can do, while connectedness forms a primary feature of the human Web. An urgent need for more intelligent agents becomes apparent, and in this paper, we demonstrate how the conjunction of functional service descriptions and hypermedia links leads to advanced, interactive agent behavior. We propose a new mode for our previously introduced semantic service description format RESTdesc, providing the mechanisms for agents to consume Web services based on links, similar to human browsing strategies. We illustrate the potential of these descriptions by a use case that shows the enhanced capabilities they offer to automated agents, and explain how this is vital for the future Web.

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    Crowdsourcing event detection in YouTube videos 58-67  Open access

     Steiner, Thomas; Verborgh, Ruben; Van de Walle, Rik; Hausenblas, Michael; Gabarro Valles, Joaquin
    Detection, Representation, and Exploitation of Events in the Semantic Web
    p. 58-67
    Presentation of work at congresses

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    Considerable efforts have been put into making video content on the Web more accessible, searchable, and navigable by research on both textual and visual analysis of the actual video content and the accompanying metadata. Nevertheless, most of the time, videos are opaque objects in websites. With Web browsers gaining more support for the HTML5

  • Tutorizando el aprendizaje proactivo de nuevas tecnologías: taller de programación Android  Open access

     Blesa Aguilera, Maria Jose; Duch Brown, Amalia; Gabarro Valles, Joaquin; Hernandez Pibernat, Hugo; Serna Iglesias, Maria Jose
    Jornadas de Enseñanza Universitaria de la Informática
    p. 321-328
    Presentation's date: 2011
    Presentation of work at congresses

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    Mediante el Programa Google EMEA’s AndroidEDU, la UPC ha impartido un novedoso taller de programación para Android. Durante diez semanas se tratan diferentes temas sobre este sistema y una veintena de alumnos trabajan ejercicios en grupos reducidos. Los grupos colaboran para investigar y solucionar las dificultades técnicas que surgen. Posteriormente, cada grupo realiza y defiende un proyecto propio. El interés en Android ha permitido fomentar el aprendizaje proactivo, con muy buenos resultados. Como profesores esta experiencia nos ha permitido afrontar nuevos retos docentes, obligándonos a replantear nuestro rol, a crear material docente adecuado a los nuevos medios de difusión social (foro FIB, YouTube, etc.), y a suplir la falta de experiencia en el tema con una interesante colaboración profesoralumno.

    SUMMARY: Within the AndroidEDU Google EMEA Program, the UPC has organized a innovative programming workshop for Android. For ten weeks, twenty students (who are organized in small groups) deal with different topics about Android. Those groups work together to investigate and resolve technical difficulties that may arise. By the end of the course, each group works on and fends for its own project.The growing interest in Android has allowed us to apply proactive learning techniques with very good results. As teachers, this experience has allowed us to meet new challenges, since it has forced us to rethink our role, to create educational material accordant with the new communication media (forum FIB, YouTube, etc.), and to supply the lack of expertise with an interesting collaboration between teachers and students.

  • Orchestrating unreliable services: strategic and probabilistic approaches to reliability

     Gabarro Valles, Joaquin; Serna Iglesias, Maria Jose; Stewart, Alan
    Symposium on Trustworthy Global Computing
    p. 23-39
    Presentation's date: 2011-09-09
    Presentation of work at congresses

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    Adding meaning to Facebook microposts via a mash-up API and tracking its data provenance  Open access

     Steiner, Thomas; Verborgh, Ruben; Gabarro Valles, Joaquin; Van de Walle, Rik
    Next Generation Web Services Practices
    p. 342-345
    DOI: 10.1109/NWeSP.2011.6088202
    Presentation's date: 2011-10-19
    Presentation of work at congresses

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    The social networking website Facebook offers to its users a feature called “status updates” (or just “status”), which allows users to create microposts directed to all their contacts, or a subset thereof. Readers can respond to microposts, or in addition to that also click a “Like” button to show their appreciation for a certain micropost. Adding semantic meaning in the sense of unambiguous intended ideas to such microposts can, for example, be achieved via Natural Language Processing (NLP). Therefore, we have implemented a RESTful mash-up NLP API, which is based on a combination of several third party NLP APIs in order to retrieve more accurate results in the sense of emergence. In consequence, our API uses third party APIs opaquely in the background in order to deliver its output. In this paper, we describe how one can keep track of provenance, and credit back the contributions of each single API to the combined result of all APIs. In addition to that, we show how the existence of provenance metadata can help understand the way a combined result is formed, and optimize the result combination process. Therefore, we use the HTTP Vocabulary in RDF and the Provenance Vocabulary. The main contribution of our work is a description of how provenance metadata can be automatically added to the output of mash-up APIs like the one presented here.

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    Stressed web environments as strategic games: Risk profiles and weltanschauung  Open access

     Gabarro Valles, Joaquin; Kilpatrick, Peter; Serna Iglesias, Maria Jose; STEWART, ALAN
    Lecture notes in computer science
    Vol. 6084, p. 189-204
    Date of publication: 2010-07-15
    Journal article

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    We consider the behaviour of a set of services in a stressed web environment where performance patterns may be di cult to pre- dict. In stressed environments the performances of some providers may degrade while the performances of others, with elastic resources, may improve. The allocation of web-based providers to users (brokering) is modelled by a strategic non-cooperative angel-daemon game with risk pro les. A risk pro le speci es a bound on the number of unreliable ser- vice providers within an environment without identifying the names of these providers. Risk pro les o er a means of analysing the behaviour of broker agents which allocate service providers to users. A Nash equilib- rium is a xed point of such a game in which no user can locally improve their choice of provider { thus, a Nash equilibrium is a viable solution to the provider/user allocation problem. Angel daemon games provide a means of reasoning about stressed environments and o er the possibility of designing brokers using risk pro les and Nash equilibria.

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  • Stressed web environments as strategic games: risk profiles and Weltanschauung

     Gabarro Valles, Joaquin; Kilpatrick, Peter; Serna Iglesias, Maria Jose; Stewart, Alan
    Symposium on Trustworthy Global Computing
    p. 1-16
    Presentation's date: 2010-02-25
    Presentation of work at congresses

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  • ALGORISMIA, BIOINFORMÀTICA, COMPLEXITAT I METODES FORMALS (ALBCOM)

     Orejas Valdes, Fernando; Galceran Oms, Marc; Oliva Valls, Sergi; Godoy Balil, Guillermo; Atserias Peri, Albert; Martinez Parra, Conrado; Pasarella Sanchez, Ana Edelmira; Pino Blanco, Elvira Patricia; Alvarez Faura, Maria Del Carme; Blum, Christian Clemens; Gabarro Valles, Joaquin; Cortadella Fortuny, Jordi; Molinero Albareda, Xavier; Serna Iglesias, Maria Jose; Messeguer Peypoch, Xavier; Roura Ferret, Salvador; Blesa Aguilera, Maria Jose; Valiente Feruglio, Gabriel Alejandro; Duch Brown, Amalia; Carmona Vargas, Jose; Hernandez Pibernat, Hugo; Gel Moreno, Bernat; Gascon Caro, Adrian; Petit Silvestre, Jordi; Diaz Cort, Jose Maria
    Competitive project

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  • Reunión del TC1 (Foundations of Computer Science)

     Hinchey, Michael; Gabarro Valles, Joaquin
    Novática: revista de la Asociación de Técnicos de Informática
    num. 199, p. 3
    Date of publication: 2009
    Journal article

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  • Sensor field: a computational model

     Alvarez Faura, Maria Del Carme; Duch Brown, Amalia; Gabarro Valles, Joaquin; Serna Iglesias, Maria Jose
    Lecture notes in computer science
    Vol. 5804, p. 3-14
    DOI: 10.1007/978-3-642-05434-1_3
    Date of publication: 2009
    Journal article

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  • Book review: Principles of protocol design

     Gabarro Valles, Joaquin
    Computer science review
    Vol. 3, num. 4, p. 259-261
    DOI: doi:10.1016/j.cosrev.2009.07.002
    Date of publication: 2009-11
    Journal article

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  • Access to the full text
    Sensor field: a computational model  Open access

     Alvarez Faura, Maria Del Carme; Duch Brown, Amalia; Gabarro Valles, Joaquin; Serna Iglesias, Maria Jose
    International Workshop on Algorithmic Aspects of Wireless Sensor Networks
    p. 5-16
    Presentation's date: 2009-07-06
    Presentation of work at congresses

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    In this work we introduce a formal model for studying networks of tiny artifacts, the static synchronous sensor field model (SSSF). The model consider that these devices communicate among them by means of a communication graph. A sensor field interacts with the environment with input/output data streams. We start analyzing the behavior of networks in which at every step each sensor takes a new input data item and outputs (with some possible latency) an output data item. Accordingly we introduce adequate performance measures like latency, message number, or message length. We study two sensing problems the Average Monitoring and the Alerting problems. For the Average Monitoring problem we give upper bounds on the latency, number of required messages and their size and optimal algorithms to solve it in specific topologies. We show that the Alerting problem can be solved with sensing devices of constant memory. When the SSSFs are allowed to use only devices with constant memory capacity we demonstrate that the decisional version of the functions computed by such SSSFs are in the class DSPACE(max(n,m)) where n is the number of nodes of the communication graph and m its number of edges. If in this kind of SSSFs we consider the possibility of using more non-sensing tiny devices than input data streams we show that monitoring a property that is polynomial time computable can be solved by SSSFs of polynomial size and latency with respect to the number of input data streams.

    Postprint (author’s final draft)

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    Sensor field: a computational model  Open access

     Alvarez Faura, Maria Del Carme; Duch Brown, Amalia; Gabarro Valles, Joaquin; Serna Iglesias, Maria Jose
    Date: 2009-09-23
    Report

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    We introduce a formal model of computation for networks of tiny artifacts, the static synchronous sensor field model (SSSF) which considers that the devices communicate through a fixed communication graph and interact with the environment through input/output data streams. We analyze the performance of SSSFs solving two sensing problems the Average Monitoring and the Alerting problems. For constant memory SSSFs we show that the set of recognized languages is contained in DSPACE(n+m) where n is the number of nodes of the communication graph and m its number of edges. Finally we explore the capabilities of SSSFs having sensing and additional non-sensing constant memory devices.

  • On the Complexity of Equilibria Problems in Angel-Daemon Games.

     Gabarro Valles, Joaquin; García, Alfredo; Serna Iglesias, Maria Jose
    Date: 2008-07
    Report

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  • Analysing Orchestrations with Risk Profiles and Angel-Daemon Games.

     Gabarro Valles, Joaquin; García, Alfredo; Serna Iglesias, Maria Jose; Kilpatrick, P; Stewart, A
    Date: 2008-07
    Report

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  • Assessing the Reliability and Cost of Web and Grid Orchestrations

     Gabarro Valles, Joaquin; Stewart, A; Clint, M; Harmer, T; Kilpatrick, P; Perrot, R
    Date of publication: 2008-03-31
    Book chapter

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  • On the Cost of Task Re-Scheduling in fault-Tolerant Task Parallel Computations

     Gabarro Valles, Joaquin; Bertolli, C
    Date of publication: 2008-04-30
    Book chapter

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  • A Markov Model for Fault-Tolerant Task Parallel Computation

     Gabarro Valles, Joaquin; Bertolli, C; Meneghin, M
    DOI: 10.1007/978-0-387-09455-7
    Date of publication: 2008-07-29
    Book chapter

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  • Topic 9: Parallel and Distributed Programming

     Gabarro Valles, Joaquin
    Lecture notes in computer science
    Vol. 5168, p. 686-687
    DOI: 10.1007/978-3-540-85451-7_73
    Date of publication: 2008-08
    Journal article

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  • reunión del TC1 (Foundations of Computer Science)

     Michael, Hinchey; Gabarro Valles, Joaquin
    Novática: revista de la Asociación de Técnicos de Informática
    num. 192, p. 31-33
    Date of publication: 2008-04
    Journal article

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  • WCC 2008: Resumen de los Eventos Plenarios

     Gabarro Valles, Joaquin
    Novática: revista de la Asociación de Técnicos de Informática
    num. 195, p. 3
    Date of publication: 2008-10
    Journal article

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  • On the Complexity of Equilibria Problems in Angel-Daemon Games

     Gabarro Valles, Joaquin; García, Alina; Serna Iglesias, Maria Jose
    Lecture notes in computer science
    Vol. 5092, p. 31-40
    Date of publication: 2008-06
    Journal article

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  • A Markov Model for Fault-Tolerant Task Parallel Computation

     Bertolli, C; Meneghin, M; Gabarro Valles, Joaquin
    Date: 2008-08
    Report

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  • Assessing the Reliability and Cost of Web and Grid Orchestrations.

     Stewart, A; Clint, M; Harmer, T; Kilpatrick, P; Perrott, R H; Gabarro Valles, Joaquin
    Date: 2008-07
    Report

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  • Analizing Orchestrations with Risk Profiles and Angel-Daemon Games

     Gabarro Valles, Joaquin; Garcia Chacon, Alina; Serna Iglesias, Maria Jose; Kilpatrick, P; Stewart, A
    Date of publication: 2008-04-30
    Book chapter

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  • Analysing Orchestrations with Risk Profiles and Angel-Daemon Games

     Gabarro Valles, Joaquin; Garcia Chacon, Alina; Serna Iglesias, Maria Jose; Kilpatrick, P; Stewart, A
    Date of publication: 2008-10-31
    Book chapter

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  • Bounded site Failures: an Approach to Unreliable Gr

     Gabarro Valles, Joaquin; Garcia Chacon, Alina; Clint, M; Kilpatrick, P; Stew, A
    Date of publication: 2008-08
    Book chapter

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