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  • 151.
    Hayashi, Masaki
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Bachelder, Steven
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Nakajima, Masayuki
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Open Framework Facilitating Automatic Generation of CG Animation from Web Site2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    We have been studying and developing the systemwhich enables to generate Computer Graphics Animation (CGA)automatically by processing HTML data of Web site. In thispaper, we propose an open framework to facilitate this. Theframework is functioning all at a server side, obtaining theHTML, converting it to a script describing the CGA story andupdating the script. And at a client side, a user accesses the scripton the server to visualize it by using real-time CG character withsynthesized voice, camera work, superimposing, sound fileplayback etc. We have constructed the framework on the serverand deployed the substantial engines to convert Web sites toCGAs. This paper describes the detail of the framework and alsoshows some example projects providing automatically generatedNews show, Talk show and personal Blog visualization.

    Fulltekst (pdf)
    fulltext
  • 152.
    Hayashi, Masaki
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Bachelder, Steven
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Nakajima, Masayuki
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Text Generated TV: A New Television System Delivering Visual Content Created Directly by Text2014Inngår i: Proceedings of IWAIT 2014, 2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    We propose a new television system based on a methodology which circulates a text-based script on the Internet representing visual content instead of transmitting complete video data. This Text Generated TV is realized by the technology called T2V (Text-To-Vision) enabling to create TV-program-like CG animation (CGA) automatically from script. Our new TV system is made by integrating the research results of T2V technology that we have been studying. The new TV system provides Use-Generated-Contents, automatic generated CGA from text sources available on the Internet, and interactive video game like applications in TV context. The Text Generated TV is regarded as one of the object-based content representation. Hence, it has a lot of possibilities and flexibilities and we believe that it has a big potential toward the future TV system. In this paper, we introduce our concept and a prototype development and discussion on new aspects of our approach.

    Fulltekst (pdf)
    TextGeneratedTV-IWAIT2014.pdf
  • 153.
    Hayashi, Masaki
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Bachelder, Steven
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Nakajima, Masayuki
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Iguchi, Akihiko
    Astrodesign, Inc..
    Virtual Museum Equipped with Automatic Video Content Generator2016Inngår i: ITE Transactions on Media Technology and Applications (MTA), E-ISSN 2186-7364, Vol. 4, nr 1, s. 41-48Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have been developing a new type of Virtual Museum which enables users to participate in the space with both active and passive modes of operation. In the "active mode", the new virtual museum provides a user walkthrough using the realistic 3DCG-modeled museum space and artifacts in the space. And in the "passive mode", the system adds desired visual and audio effects such as camerawork, superimposed text, synthesized voice narration, post production processes, background music and so on to give users a TV commentary type of CG animation. Users can easily transition back and forth between the two modes of doing walkthrough in the space actively and watching the video content passively. This paper describes the details of the system design and the implementation followed by a discussion on the functioning prototype.

    Fulltekst (pdf)
    fulltext
  • 154.
    Hayashi, Masaki
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Bachelder, Steven
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Nakajima, Masayuki
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Nigorikawa, Takesato
    ProgMind, Inc..
    System Development Kit of T2V in the Unity: T2V Engine Capable of Converting Script to CG Animation in the Unity Game Engine2014Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    T2V (Text-To-Vision) is the technology which enables to generate TV-program-like CG animation by computer from a given script. In this time, we have developed a system development kit (SDK) which makes it possible for developers to create various interactive applications in the Unity with utilizing the T2V technology. We first explain the SDK and its usage. Secondly, we introduce two applications made using SDK: 1) Automatic generation of talk show from a bulletin board in the Internet, 2) Interactive quiz application with multi-story structure.

    Fulltekst (pdf)
    fulltext
  • 155.
    Hayashi, Masaki
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Bachelder, Steven
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Tsuruta, Naoya
    Tokyo University of Technology, Tokyo, Japan.
    Sasaki, Kazuo
    Tokyo University of Technology, Tokyo, Japan.
    Kondo, Kunio
    Tokyo University of Technology, Tokyo, Japan.
    Wordpress-based Blog System with a Capability of Showing Entries by TV-program-like CG Animations2018Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    We have developed a blog system with Wordpress which has a capability of automatically converting its blog entries into CG animations. By embedding necessary functions in Wordpress' s theme, a user can select this theme and construct a blog where readers can watch CG animation instead of reading the blog entry. The CG animation is created by TVML (TV program Making Language) technology which enables to make a TV-program-like animation with CG characters with synthesized voices, image data display, sound data playback, superimposing and so on. Not only to contribute to the Wordpress community, in particular, expected as an auxiliary function of the blog service, but also this could work as a production tool for creating various types of CG animations rather than blogging assistance.

    Fulltekst (pdf)
    fulltext
  • 156.
    Hayashi, Masaki
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Bachelder, Steven
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Tsuruta, Naoya
    School of Media Science, Tokyo University of Technology.
    Teraoka, Takehiro
    School of Media Science, Tokyo University of Technology.
    Sasaki, Kazuo
    School of Media Science, Tokyo University of Technology.
    Usami, Wataru
    School of Media Science, Tokyo University of Technology.
    Mikami, Koji
    School of Media Science, Tokyo University of Technology.
    Kikuchi, Tsukasa
    School of Media Science, Tokyo University of Technology.
    Takeshima, Yuriko
    School of Media Science, Tokyo University of Technology.
    Kondo, Kunio
    School of Media Science, Tokyo University of Technology.
    Automatic Generation of a TV Programme from Blog Entries2018Inngår i: Adjunct Proceedings of ACM TVX2018, 2018Konferansepaper (Fagfellevurdert)
    Abstract [en]

    TVML (TV program Making Language) is a technology capable of obtaining TV (television)-programme-like Computer Graphics (CG) animation by writing text script. We have originally developed TVML and have been studying generative contents with the aid of TVML. This time, we have created an application that automatically converts blog posts into CG animations with TV news show format. The process is: 1) to fetch HTML of the blog posts and perform Web scraping and natural language processing to obtain summarized speech texts, 2) to automatically give a show format obtained from the analysis of professional TV programme to get TVML script, 3) to apply the CG character and artworks etc. that fit the blog content to obtain the final CG animation. In the demo session, we will explain the method and will demonstrate the working application on a PC connected to the Internet showing CG animations actually created on site.

    Fulltekst (pdf)
    fulltext
  • 157.
    Hayashi, Masaki
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Inoue, Seiki
    Douke, Mamoru
    Hamaguchi, Narichika
    Kaneko, Hiroyuki
    Bachelder, Steven
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Nakajima, Masayuki
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    T2V: New Technology of Converting Text to CG Animation2014Inngår i: ITE Transactions on Media Technology and Applications (MTA), ISSN 2186-7364, Vol. 2, nr 1, s. 74-82Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have developed a technology that enables the creation of TV-program-like CG animationgenerated automatically from text-based script. We call this technology "T2V (Text-To-Vision)" and havedeveloped a PC application that we call the "T2V Player." The application allows users to create animationsinstantly by simply typing in text in a customary fashion as when writing on a word processor. The T2V Playeremploys a unique framework with a capability to accommodate any text processing module to realize any type oftext-to-animation conversion. The T2V Player is not only an animation tool for writers creating animations fromtheir texts, but also an application of various text-to-vision services such as automatic animation generationform Web sites and other text sources. This paper describes the concept of T2V and the technical specifications ofthe T2V Player and its benefits.

  • 158.
    Hayashi, Masaki
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Kameoka, Masahiro
    Tokyo University of Science.
    Furukawa, Toshihiro
    Tokyo University of Science.
    Quiz Generation from Web News Source Based on Heuristic Algorithm2016Konferansepaper (Annet (populærvitenskap, debatt, mm))
  • 159.
    Hayashi, Masaki
    et al.
    Högskolan på Gotland, Institutionen för speldesign, teknik och lärande.
    Nakajima, Masayuki
    Högskolan på Gotland, Institutionen för speldesign, teknik och lärande.
    Bachelder, Steven
    Högskolan på Gotland, Institutionen för speldesign, teknik och lärande.
    Iguchi, Akihiko
    Machida, Satoshi
    Virtual Museum on 4K Ultra-high Resolution Real-time CG System2013Inngår i: Proceedings of Virtual Reality Technical Seminar, 2013Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    We have researched and developed a 'Virtual Museum' in an extreme high-definition real-time computer graphics system with a resolution of 4K and 8K (Super Hi-Vision). We have first developed a functioning test system, which exhibits Japanese artifacts 'Ukiyoe and pannel' in 4K resolution. In our system, the artifacts have been digitized in ultra high-resolution then positioned in a high-quality modeled exhibition space. A user can walkthrough in the exhibition space enabling to view the artifacts in a distance and also to get closer to observe its detailed surface seamlessly. With this method, we have successfully enhanced both sense of being there and sense of realness. In this paper, we first survey several virtual museums in practical use, then explain the detail of our system and introduce experiment results with discussion in comparison with the existing virtual museums.

    Fulltekst (pdf)
    fulltext
  • 160.
    Hayashi, Masaki
    et al.
    Högskolan på Gotland, Institutionen för speldesign, teknik och lärande.
    Nakajima, Masayuki
    Högskolan på Gotland, Institutionen för speldesign, teknik och lärande.
    Bachelder, Steven
    Högskolan på Gotland, Institutionen för speldesign, teknik och lärande.
    Nigorikawa, Takesato
    Implementation of T2V: Text-To-Visio on Game Engine UNITY2013Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    We have been developing T2V (Text-To-Vision) technology which enables to produce CG animation from given script. We have developed the application called 'T2V Player' and have been distributed it as freeware for years. The application works on Windows PC to produce TV-program-like animation from user input text using real-time CG and voice synthesizing technique, etc. In this paper, we introduce the prototype of 'T2V on UNITY' which has been developed from scratch on the UNITY game engine. We succeeded to enhance its function owing to the UNITY, such as multi-platform, availability of CG character data circulated on UNITY community, capability of applying T2V method to game development and more.

    Fulltekst (pdf)
    fulltext
  • 161.
    Haziza, Frédéric
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för datorteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Few is Just Enough!: Small Model Theorem for Parameterized Verification and Shape Analysis2015Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This doctoral thesis considers the automatic verification of parameterized systems, i.e. systems with an arbitrary number of communicating components, such as mutual exclusion protocols, cache coherence protocols or heap manipulating programs. The components may be organized in various topologies such as words, multisets, rings, or trees.

    The task is to show correctness regardless of the size of the system and we consider two methods to prove safety:(i) a backward reachability analysis, using the well-quasi ordered framework and monotonic abstraction, and (ii) a forward analysis which only needs to inspect a small number of components in order to show correctness of the whole system. The latter relies on an abstraction function that views the system from the perspective of a fixed number of components. The abstraction is used during the verification procedure in order to dynamically detect cut-off points beyond which the search of the state-space need not continue.

    Our experimentation on a variety of benchmarks demonstrate that the method is highly efficient and that it works well even for classes of systems with undecidable property. It has been, for example, successfully applied to verify a fine-grained model of Szymanski's mutual exclusion protocol. Finally, we applied the methods to solve the complex problem of verifying highly concurrent data-structures, in a challenging setting: We do not a priori bound the number of threads, the size of the data-structure, the domain of the data to store nor do we require the presence of a garbage collector. We successfully verified the concurrent Treiber's stack and Michael & Scott's queue, in the aforementioned setting.

    To the best of our knowledge, these verification problems have been considered challenging in the parameterized verification community and could not be carried out automatically by other existing methods.

    Delarbeid
    1. All for the price of few: (Parameterized verification through view abstraction)
    Åpne denne publikasjonen i ny fane eller vindu >>All for the price of few: (Parameterized verification through view abstraction)
    2013 (engelsk)Inngår i: Verification, Model Checking, and Abstract Interpretation, Springer Berlin/Heidelberg, 2013, s. 476-495Konferansepaper, Publicerat paper (Fagfellevurdert)
    sted, utgiver, år, opplag, sider
    Springer Berlin/Heidelberg, 2013
    Serie
    Lecture Notes in Computer Science ; 7737
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-190003 (URN)10.1007/978-3-642-35873-9_28 (DOI)978-3-642-35872-2 (ISBN)
    Konferanse
    VMCAI 2013, January 20-22, Rome, Italy
    Prosjekter
    UPMARC
    Tilgjengelig fra: 2013-01-09 Laget: 2013-01-07 Sist oppdatert: 2015-11-10bibliografisk kontrollert
    2. An Integrated Specification and Verification Technique for Highly Concurrent Data Structures
    Åpne denne publikasjonen i ny fane eller vindu >>An Integrated Specification and Verification Technique for Highly Concurrent Data Structures
    Vise andre…
    2013 (engelsk)Inngår i: Tools and Algorithms for the Construction and Analysis of Systems, 2013Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    We present a technique for automatically verifying safety properties of concurrent programs, in particular programs which rely on subtle dependen- cies of local states of different threads, such as lock-free implementations of stacks and queues in an environment without garbage collection. Our technique addresses the joint challenges of infinite-state specifications, an unbounded num- ber of threads, and an unbounded heap managed by explicit memory allocation. Our technique builds on the automata-theoretic approach to model checking, in which a specification is given by an automaton that observes the execution of a program and accepts executions that violate the intended specification. We extend this approach by allowing specifications to be given by a class of infinite-state au- tomata. We show how such automata can be used to specify queues, stacks, and other data structures, by extending a data-independence argument. For verifica- tion, we develop a shape analysis, which tracks correlations between pairs of threads, and a novel abstraction to make the analysis practical. We have imple- mented our method and used it to verify programs, some of which have not been verified by any other automatic method before.

    Emneord
    verification, pointer program, queue, stack, unbounded concurrency, specification, linearizability
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-191330 (URN)
    Konferanse
    19th International Conference on Tools and Algorithms for the Construction and Analysis of Systems (TACAS), 16-24 March, 2013, Rome, ITALY
    Prosjekter
    UPMARC
    Tilgjengelig fra: 2013-01-16 Laget: 2013-01-10 Sist oppdatert: 2018-01-11bibliografisk kontrollert
    3. Block me if you can!: Context-sensitive parameterized verification
    Åpne denne publikasjonen i ny fane eller vindu >>Block me if you can!: Context-sensitive parameterized verification
    2014 (engelsk)Inngår i: Static Analysis: SAS 2014, Springer, 2014, s. 1-17Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    We present a method for automatic verification of systems with a parameterized number of communicating processes, such as mutual exclusion protocols or agreement protocols. To that end, we present a powerful abstraction framework that uses an efficient and precise symbolic encoding of (infinite) sets of configurations. In particular, it generalizes downward-closed sets that have successfully been used in earlier approaches to parameterized verification. We show experimentally the efficiency of the method, on various examples, including a fine-grained model of Szymanski’s mutual exclusion protocol, whose correctness, to the best of our knowledge, has not been proven automatically by any other existing methods.

    sted, utgiver, år, opplag, sider
    Springer, 2014
    Serie
    Lecture Notes in Computer Science, ISSN 0302-9743 ; 8723
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-260087 (URN)10.1007/978-3-319-10936-7_1 (DOI)000360204700001 ()978-3-319-10935-0 (ISBN)
    Konferanse
    21st International Symposium, SAS 2014, September 11–13, Munich, Germany
    Prosjekter
    UPMARC
    Tilgjengelig fra: 2014-09-13 Laget: 2015-08-15 Sist oppdatert: 2015-12-16bibliografisk kontrollert
    4. Monotonic abstraction for programs with dynamic memory heaps
    Åpne denne publikasjonen i ny fane eller vindu >>Monotonic abstraction for programs with dynamic memory heaps
    Vise andre…
    2008 (engelsk)Inngår i: Computer Aided Verification / [ed] Gupta A, Malik S, Berlin: Springer-Verlag , 2008, s. 341-354Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    We propose a new approach for automatic verification of programs with dynamic heap manipulation. The method is based on symbolic (backward) reachability analysis using upward-closed sets of heaps w.r.t. an appropriate preorder on graphs. These sets are represented by a finite set of minimal graph patterns corresponding to a set of bad configurations. We define an abstract semantics for the programs which is monotonic w.r.t. the preorder. Moreover, we prove that our analysis always terminates by showing that the preorder is a well-quasi ordering. Our results are presented for the case of programs with 1-next selector. We provide experimental results showing the effectiveness of our approach.

    sted, utgiver, år, opplag, sider
    Berlin: Springer-Verlag, 2008
    Serie
    Lecture Notes in Computer Science, ISSN 0302-9743 ; 5123
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-106059 (URN)10.1007/978-3-540-70545-1_33 (DOI)000257539900033 ()
    Konferanse
    20th International Conference on Computer Aided Verification Princeton, NJ, JUL 07, 2008
    Tilgjengelig fra: 2009-06-13 Laget: 2009-06-13 Sist oppdatert: 2018-01-13bibliografisk kontrollert
    5. Parameterized tree systems
    Åpne denne publikasjonen i ny fane eller vindu >>Parameterized tree systems
    Vise andre…
    2008 (engelsk)Inngår i: Formal Techniques for Networked and Distributed Systems: FORTE 2008 / [ed] Suzuki K, Berlin: Springer-Verlag , 2008, s. 69-83Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    Several recent works have considered parameterized verification, i.e. automatic verification of systems consisting of an arbitrary number of finite-state processes organized in a linear array. The aim of this paper is to extend these works by giving a simple and efficient method to prove safety properties for systems with tree-like architectures. A process in the system is a finite-state automaton and a transition is performed jointly by a process and its parent and children processes. The method derives an over-approximation of the induced transition system, which allows the use of finite trees as symbolic representations of infinite sets of configurations. Compared to traditional methods for parameterized verification of systems with tree topologies, our method does not require the manipulation of tree transducers, hence its simplicity and efficiency. We have implemented a prototype which works well on several nontrivial tree-based protocols.

    sted, utgiver, år, opplag, sider
    Berlin: Springer-Verlag, 2008
    Serie
    Lecture Notes in Computer Science, ISSN 0302-9743 ; 5048
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-106058 (URN)10.1007/978-3-540-68855-6_5 (DOI)000256666500005 ()978-3-540-68854-9 (ISBN)
    Konferanse
    28th International Conference on Formal Techniques for Networked and Distributed Systems Tokyo, JAPAN, JUN 10-13, 2008
    Tilgjengelig fra: 2009-06-13 Laget: 2009-06-13 Sist oppdatert: 2018-01-13bibliografisk kontrollert
    6. Model checking race-freeness
    Åpne denne publikasjonen i ny fane eller vindu >>Model checking race-freeness
    2008 (engelsk)Inngår i: SIGARCH Computer Architecture News, ISSN 0163-5964, E-ISSN 1943-5851, Vol. 36, nr 5, s. 72-79Artikkel i tidsskrift (Fagfellevurdert) Published
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-142914 (URN)10.1145/1556444.1556454 (DOI)
    Tilgjengelig fra: 2011-01-17 Laget: 2011-01-17 Sist oppdatert: 2018-01-12bibliografisk kontrollert
    7. Parameterized verification through view abstraction
    Åpne denne publikasjonen i ny fane eller vindu >>Parameterized verification through view abstraction
    2016 (engelsk)Inngår i: International Journal on Software Tools for Technology Transfer (STTT), ISSN 1433-2779, E-ISSN 1433-2787, Vol. 18, nr 5, s. 495-516Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    We present a simple and efficient framework for automatic verification of systems with a parametric number of communicating processes. The processes may be organized in various topologies such as words, multisets, rings, or trees. Our method needs to inspect only a small number of processes in order to show correctness of the whole system. It relies on an abstraction function that views the system from the perspective of a fixed number of processes. The abstraction is used during the verification procedure in order to dynamically detect cut-off points beyond which the search of the state space need not continue. We show that the method is complete for a large class of well quasi-ordered systems including Petri nets. Our experimentation on a variety of benchmarks demonstrate that the method is highly efficient and that it works well even for classes of systems with undecidable verification problems. In particular, the method handles the fine-grained and full version of Szymanski's mutual exclusion protocol, whose correctness, to the best of our knowledge, has not been proven automatically by any other existing methods.

    Emneord
    Parameterized systems; Safety; Small model properties; View abstraction
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-260089 (URN)10.1007/s10009-015-0406-x (DOI)000382011100003 ()
    Prosjekter
    UPMARC
    Tilgjengelig fra: 2015-11-23 Laget: 2015-08-15 Sist oppdatert: 2017-12-04bibliografisk kontrollert
    Fulltekst (pdf)
    fulltext
    Download (jpg)
    presentationsbild
  • 162. He, Zhitao
    et al.
    Hewage, Kasun
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Voigt, Thiemo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Arpeggio: a penetration attack on glossy networks2016Inngår i: Proc. 13th International Conference on Sensing, Communication, and Networking, IEEE, 2016, s. 37-45Konferansepaper (Fagfellevurdert)
  • 163.
    Hedlund, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära.
    Hammarström, Simon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära.
    Design och framtagande av mätanordning för ström och effek på trefas ledare: Josi Periferi strömmeter2015Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    The assignment is issued by Scania Maintence AB seeking a new approach to detect power changes in their industrial processes. The work has taken place at Ångströmslaboratoriet and tests have been performed at Scania AB Södertälje.

    Today’s society consumes enormous amount of energy. In both economically and environmental view, it is important that the processes are effective, with high power factor. There are many ways to measure power in the industry, what they all have in common is that the installation is advanced, requires time and planning. Only a competent electrician may install the measuring device in the distribution box. The purpose of the project is to build a prototype for power measurement that can be easily used outside the distribution box, thus simplifying the procedure and shortening the time required. By attaching sensors around the supply cable, the magnetic field asymmetric flux density can be used and induce voltage proportional to the current in the cable.

    The result is an instrument that with a computer calculates current, phase angle and power. Measurements of the current rms value showed that the maximum difference between our prototype and Scania Maintenances equipmentis up to 29 percent. However, for a longer time (> 15 minutes) the differences between the mean values are only 1.2 percent and the accuracy is calculated to +/-3.67A with 95% confidence intervals. Phase angle accuracy measured to plus 6 minus and 15 percent.

    Fulltekst (pdf)
    fulltext
  • 164.
    Helmisaari, Marc
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Det beroendeframkallande klicket: Engagerande och emotionella icke-spel2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    En ny spelgenre har ökat i popularitet de senaste fem åren. En spelgenre som faller utanför den klassiska definitionen av spel. En spelgenre vid namn ”Idle Games”. Föreliggande studie handlar om vilka element i dessa spel som får spelaren att fortsätta spela och hur elementen kan analyseras med hjälp av MDA och AARRR ramverken. Data har samlats in från tre populära Idle Games vid namn Cookie Clicker, Clicker Heroes och AdVenture Capatalist. En enkät har också skickats till spelarna av dessa spel för att få en uppfattning om varför spelen är populära. Resultaten har sedan analyserats med olika speldesignteorier för att undersöka vilka spelmekaniker som skapar lusten att spela och varför dessa spel är populära.

    Fulltekst (pdf)
    fulltext
  • 165.
    Henriksson, Michael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi.
    A Cognitive Work Analysis as Basis for Development of a Compact C2 System to Support Air Surveillance Work2012Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    This Master of Science thesis is producedat SAAB Security and Defence Solutions.The purpose of the thesis is to analyzehow air surveillance work can be carriedout. This information is then used to givesuggestions for the design of a new systemcontaining only the most essentialfunctionality. This is done by examiningthe available frameworks which can informinterface design and applying a frameworkto analyze work in a complete system usedas the basis of the new Compact C2 system.The second part of the analysis isdirected towards the stripped system(Compact C2) and both parts of theanalysis are used to inform interfacedesign of the Compact C2 system. By usingthe full range of the chosen framework foranalysis of the identification process inSwedish air surveillance work, someessential functions were identified andshould also have support in a Compact C2 system.

    Fulltekst (pdf)
    A Cognitive Work Analysis as Basis for Development of a Compact C2 System to Support Air Surveillance Work
  • 166.
    Hermans, Frederik
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Rensfelt, Olof
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Voigt, Thiemo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Ngai, Edith
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Nordén, Lars-Åke
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Gunningberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    SoNIC: Classifying interference in 802.15.4 sensor networks2013Inngår i: Proc. 12th International Conference on Information Processing in Sensor Networks, New York: ACM Press, 2013, s. 55-66Konferansepaper (Fagfellevurdert)
  • 167.
    Hnich, Brahim
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för informationsvetenskap.
    Kiziltan, Zeynep
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för informationsvetenskap.
    Walsh, Toby
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för informationsvetenskap.
    Modelling a Balanced Academic Curriculum Problem2002Inngår i: Proceedings CPAIOR 2002, 2002Konferansepaper (Fagfellevurdert)
  • 168.
    Hojjat, Hossein
    et al.
    Cornell Univ, Ithaca, NY 14853 USA..
    Rümmer, Philipp
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    McClurg, Jedidiah
    CU Boulder, Boulder, CO USA..
    Cerny, Pavol
    CU Boulder, Boulder, CO USA..
    Foster, Nate
    Cornell Univ, Ithaca, NY 14853 USA..
    Optimizing Horn Solvers for Network Repair2016Inngår i: Proceedings of the 2016 16Th Conference on Formal Methods In Computer-Aided Design (FMCAD 2016) / [ed] Piskac, R Talupur, M, IEEE , 2016, s. 73-80Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Automatic program repair modifies a faulty program to make it correct with respect to a specification. Previous approaches have typically been restricted to specific programming languages and a fixed set of syntactical mutation techniques-e.g., changing the conditions of if statements. We present a more general technique based on repairing sets of unsolvable Horn clauses. Working with Horn clauses enables repairing programs from many different source languages, but also introduces challenges, such as navigating the large space of possible repairs. We propose a conservative semantic repair technique that only removes incorrect behaviors and does not introduce new behaviors. Our proposed framework allows the user to request the best repairs-it constructs an optimization lattice representing the space of possible repairs, and uses a novel local search technique that exploits heuristics to avoid searching through sub-lattices with no feasible repairs. To illustrate the applicability of our approach, we apply it to problems in software-defined networking (SDN), and illustrate how it is able to help network operators fix buggy configurations by properly filtering undesired traffic. We show that interval and Boolean lattices are effective choices of optimization lattices in this domain, and we enable optimization objectives such as modifying the minimal number of switches. We have implemented a prototype repair tool, and present preliminary experimental results on several benchmarks using real topologies and realistic repair scenarios in data centers and congested networks.

  • 169.
    Homewood, Thomas
    et al.
    Swedish Institute of Computer Science.
    Norström, Christer
    Swedish Institute of Computer Science.
    Gunningberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Skitracker: Measuring skiing performance using a body-area network2013Inngår i: Proc. 12th International Conference on Information Processing in Sensor Networks, New York: ACM Press, 2013, s. 319-320Konferansepaper (Fagfellevurdert)
  • 170. Hossain, Adnan
    Synliggörande av provfordonets elsystemstatus2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Projektets mål är att utveckla ett eller flera program för att möta de behov systemutvecklarna har. I dagsläget är det väldigt problematiskt att bestämma en lastbils konfiguration sett på elsystem. Det krävs en stor teknisk bakgrund samt att det är väldigt tidskrävande. Detta i sin tur leder till att processen för systemtester dröjer och allt testandet av lastbilar tar längre tid. Lastbilarna som är prototyper byggs efter framtidens behov och kräver kontinuerligt testande. Därav är önskemålen stor kring utvecklandet av ett program som minimerar tidsförlusten och som inte kräver en så stor teknisk bakgrund. Utvecklandet skedde i Microsoft Visual Studio som är ett utvecklarprogram där programmeringsspråket är C\# och asp .net. För hanteringen av data gällande bilarna så användes databaser där dataflödet styrdes med hjälp av frågespråket SQL. Resultatet av projektet vart en webbapplikation och en uppgradering av ett befintligt program. I detta skede är webbapplikationen och det tillhörande programmet ute på testning bland Scania anställda och framtida uppdateringar och justeringar är inplanerade.

    Fulltekst (pdf)
    synliggörande av provfordonets elsystemstatus
  • 171.
    Jacobsson, Martin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Orfanidis, Charalampos
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Using software-defined networking principles for wireless sensor networks2015Inngår i: Proc. 11th Swedish National Computer Networking Workshop, 2015Konferansepaper (Fagfellevurdert)
    Fulltekst (pdf)
    fulltext
  • 172.
    Johansson, Magnus
    et al.
    Stockholms universitet, Institutionen för data- och systemvetenskap.
    Verhagen, Harko
    Stockholms universitet, Institutionen för data- och systemvetenskap.
    Massively multiple online role playing games as normative multiagent systems2009Inngår i: Normative Multi-Agent Systems, Guido Boella, Pablo Noriega, Gabriella Pigozzi, and Harko Verhagen , 2009Konferansepaper (Annet vitenskapelig)
  • 173.
    Jonsson, Kristoffer
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Lundberg, David
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper.
    Digital Interface for Intelligent Sensors2013Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Digital Interface for Intelligent Sensors was a project whose goal was to create a digital network interface that enabled easy distribution of data from different types of digital sensors to a central computer. The purpose was to replace the already existing analogue data collection system, in order to benefit from the advantages of digital communication. This demanded a software protocol that satisfyingly would be implementable on a microcontroller. Along with software implementation the specific objective was to design, construct and build an intelligent hardware sensor device. This device was supposed to measure temperature, humidity, wind direction and wind speed by collecting information from adequate digital transducers.

    The project involved researches about bus-protocols as well as practically design and build circuits. A lot of software programming was made during the project, to get the device to work as expected. During research the Modbus-protocol was found to be the best option for our specific software needs. As for the hardware part, the core of the sensor device was based on an ATmega328 microcontroller. The ATmega328 proved to be a suitable hardware platform for implementing both the Modbus-protocol and the necessary code required to extract information from the transducers. By linking a computer to the system, working as a master, weather data from the device were able to be logged.

    The device was successfully installed on the roof at Ångströmslaboratoriet, house 2. The complete system enables other digital, Modbus implemented, devices to connect in order to communicate with the central computer. Having many devices can lead to rather complex systems. The system created in this project keeps track on all the installed devices using addresses, making a complex system easy to manage.

    The project also involved a brief collaboration with another group constructing a different digital measuring device. This device was able to connect to the system using the same Modbus-protocol and thereby communicating with the central computer.

    Fulltekst (pdf)
    fulltext
  • 174.
    Jouet, Antoine
    et al.
    University of Angers.
    Gac, Pierre
    University of Angers.
    Hayashi, Masaki
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Bachelder, Steven
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    Nakajima, Masayuki
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    When virtual reality meet television: Use of a motor Text-To-Vision adapted for the television2015Inngår i: Proceedings of Art and Science Forum 2015, 2015Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    This paper explains and details an automated TV News Show program, using the Text-To-Vision (T2V) technology. Today, 3D CG environments are more and more often used, even in the classic media like TV. However, there is not any fully virtual TV News Show coming yet, staring only virtual characters with being completely automated, using news source available on the Internet. We made it possible to create this kind of automatic news show system owing to the T2V, with interactive avatars, facial expressions and multiple modular and dynamic scenes.

  • 175.
    Kameoka, Masahiro
    et al.
    Tokyo University of Science.
    Furukawa, Toshihiro
    Tokyo University of Science.
    Hayashi, Masaki
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för speldesign.
    発見的手法によるWebニュースからのクイズ自動生成の試み2015Inngår i: Proceedings of Art and Science Forum 2015, 2015Konferansepaper (Annet vitenskapelig)
    Abstract [ja]

    本研究では、コンテンツ制作技術の1つとしてWebコンテンツの再利用を目的に,Webニュース記事を情報源としたクイズコンテンツの自動生成を試みる.これまで行われてきたクイズコンテンツ自動生成の関連研究は主に分析的方法によるものだが、本研究は,元となる文章から人間がクイズを作る時の思考を追ってコンピュータにシミュレートさせる発見的手法を用いている.発見的手法によりクイズの自動生成が可能であるかを実験で示し,考察を行う.

  • 176.
    Kameoka, Masahiro
    et al.
    Tokyo University of Science.
    Hayashi, Masaki
    Högskolan på Gotland, Institutionen för speldesign, teknik och lärande.
    Furukawa, Toshihiro
    Tokyo University of Science.
    Improvement of Automatic BBS Visualization in T2V: Animation considering dialogue structure2013Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    T2V(Text-to-Vision) a technology which is capable of automatic animated movie generation to assist individuals who do not have special knowledge about animation production. This paper shows improvement of the function that animates BBS (Bulletin Board System) with this technology. T2V has a package (2ch convertor) that is capable of animating “2channel” (largest BBS in Japan). The present 2ch convertor, however, does not support dialogue situation based on quotation marks. Therefore, it causes a problem that it cannot produce animation with dialogue. In this paper we propose a method of animation production regarding the conversation structure in BBS to create more natural expression in the animation.

    Fulltekst (pdf)
    BBSVisualization
  • 177.
    Kaxiras, Stefanos
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Ros, Alberto
    A New Perspective for Efficient Virtual-Cache Coherence2013Inngår i: Proceedings of the 40th Annual International Symposium on Computer Architecture, 2013, s. 535-546Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Coherent shared virtual memory (cSVM) is highly coveted for heterogeneous architectures as it will simplify program- ming across different cores and manycore accelerators. In this context, virtual L1 caches can be used to great advan- tage, e.g., saving energy consumption by eliminating address translation for hits. Unfortunately, multicore virtual-cache coherence is complex and costly because it requires reverse translation for any coherence request directed towards a vir- tual L1. The reason is the ambiguity of the virtual address due to the possibility of synonyms. In this paper, we take a radically different approach than all prior work which is focused on reverse translation. We examine the problem from the perspective of the coherence protocol. We show that if a coherence protocol adheres to certain conditions, it operates effortlessly with virtual caches, without requir- ing reverse translations even in the presence of synonyms. We show that these conditions hold in a new class of simple and efficient request-response protocols that use both self- invalidation and self-downgrade.This results in a new solu- tion for virtual-cache coherence, significantly less complex and more efficient than prior proposals. We study design choices for TLB placement under our proposal and compare them against those under a directory-MESI protocol. Our approach allows for choices that are particularly effective as for example combining all per-core TLBs in a single logical TLB in front of the last level cache. Significant area, energy, and performance benefits ensue as a result of simplifying the entire multicore memory organization. 

  • 178.
    Khan, Muneeb
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Sembrant, Andreas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Hagersten, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Low Overhead Instruction-Cache Modeling Using Instruction Reuse Profiles2012Inngår i: International Symposium on Computer Architecture and High Performance Computing (SBAC-PAD'12), IEEE Computer Society , 2012, s. 260-269Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Performance loss caused by L1 instruction cache misses varies between different architectures and cache sizes. For processors employing power-efficient in-order execution with small caches, performance can be significantly affected by instruction cache misses. The growing use of low-power multi-threaded CPUs (with shared L1 caches) in general purpose computing platforms requires new efficient techniques for analyzing application instruction cache usage. Such insight can be achieved using traditional simulation technologies modeling several cache sizes, but the overhead of simulators may be prohibitive for practical optimization usage. In this paper we present a statistical method to quickly model application instruction cache performance. Most importantly we propose a very low-overhead sampling mechanism to collect runtime data from the application's instruction stream. This data is fed to the statistical model which accurately estimates the instruction cache miss ratio for the sampled execution. Our sampling method is about 10x faster than previously suggested sampling approaches, with average runtime overhead as low as 25% over native execution. The architecturally-independent data collected is used to accurately model miss ratio for several cache sizes simultaneously, with average absolute error of 0.2%. Finally, we show how our tool can be used to identify program phases with large instruction cache footprint. Such phases can then be targeted to optimize for reduced code footprint.

  • 179.
    Koukos, Konstantinos
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för datorteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Efficient Execution Paradigms for Parallel Heterogeneous Architectures2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis proposes novel, efficient execution-paradigms for parallel heterogeneous architectures. The end of Dennard scaling is threatening the effectiveness of DVFS in future nodes; therefore, new execution paradigms are required to exploit the non-linear relationship between performance and energy efficiency of memory-bound application-regions. To attack this problem, we propose the decoupled access-execute (DAE) paradigm. DAE transforms regions of interest (at program-level) in two coarse-grain phases: the access-phase and the execute-phase, which we can independently DVFS. The access-phase is intended to prefetch the data in the cache, and is therefore expected to be predominantly memory-bound, while the execute-phase runs immediately after the access-phase (that has warmed-up the cache) and is therefore expected to be compute-bound.

    DAE, achieves good energy savings (on average 25% lower EDP) without performance degradation, as opposed to other DVFS techniques. Furthermore, DAE increases the memory level parallelism (MLP) of memory-bound regions, which results in performance improvements of memory-bound applications. To automatically transform application-regions to DAE, we propose compiler techniques to automatically generate and incorporate the access-phase(s) in the application. Our work targets affine, non-affine, and even complex, general-purpose codes. Furthermore, we explore the benefits of software multi-versioning to optimize DAE in dynamic environments, and handle codes with statically unknown access-phase overheads. In general, applications automatically-transformed to DAE by our compiler, maintain (or even exceed in some cases) the good performance and energy efficiency of manually-optimized DAE codes.

    Finally, to ease the programming environment of heterogeneous systems (with integrated GPUs), we propose a novel system-architecture that provides unified virtual memory with low overhead. The underlying insight behind our work is that existing data-parallel programming models are a good fit for relaxed memory consistency models (e.g., the heterogeneous race-free model). This allows us to simplify the coherency protocol between the CPU – GPU, as well as the GPU memory management unit. On average, we achieve 45% speedup and 45% lower EDP over the corresponding SC implementation.

    Delarbeid
    1. Towards more efficient execution: a decoupled access-execute approach
    Åpne denne publikasjonen i ny fane eller vindu >>Towards more efficient execution: a decoupled access-execute approach
    2013 (engelsk)Inngår i: Proc. 27th ACM International Conference on Supercomputing, New York: ACM Press, 2013, s. 253-262Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    The end of Dennard scaling is expected to shrink the range of DVFS in future nodes, limiting the energy savings of this technique. This paper evaluates how much we can increase the effectiveness of DVFS by using a software decoupled access-execute approach. Decoupling the data access from execution allows us to apply optimal voltage-frequency selection for each phase and therefore improve energy efficiency over standard coupled execution.

    The underlying insight of our work is that by decoupling access and execute we can take advantage of the memory-bound nature of the access phase and the compute-bound nature of the execute phase to optimize power efficiency, while maintaining good performance. To demonstrate this we built a task based parallel execution infrastructure consisting of: (1) a runtime system to orchestrate the execution, (2) power models to predict optimal voltage-frequency selection at runtime, (3) a modeling infrastructure based on hardware measurements to simulate zero-latency, per-core DVFS, and (4) a hardware measurement infrastructure to verify our model's accuracy.

    Based on real hardware measurements we project that the combination of decoupled access-execute and DVFS has the potential to improve EDP by 25% without hurting performance. On memory-bound applications we significantly improve performance due to increased MLP in the access phase and ILP in the execute phase. Furthermore we demonstrate that our method can achieve high performance both in presence or absence of a hardware prefetcher.

    sted, utgiver, år, opplag, sider
    New York: ACM Press, 2013
    Emneord
    Task-Based Execution, Decoupled Execution, Performance, Energy, DVFS
    HSV kategori
    Forskningsprogram
    Datorteknik
    Identifikatorer
    urn:nbn:se:uu:diva-203239 (URN)10.1145/2464996.2465012 (DOI)978-1-4503-2130-3 (ISBN)
    Konferanse
    ICS 2013, June 10-14, Eugene, OR
    Prosjekter
    LPGPU FP7-ICT-288653UPMARC
    Forskningsfinansiär
    EU, FP7, Seventh Framework Programme, ICT-288653Swedish Research Council
    Tilgjengelig fra: 2013-07-06 Laget: 2013-07-05 Sist oppdatert: 2016-09-02bibliografisk kontrollert
    2. Fix the code. Don't tweak the hardware: A new compiler approach to Voltage–Frequency scaling
    Åpne denne publikasjonen i ny fane eller vindu >>Fix the code. Don't tweak the hardware: A new compiler approach to Voltage–Frequency scaling
    Vise andre…
    2014 (engelsk)Inngår i: Proc. 12th International Symposium on Code Generation and Optimization, New York: ACM Press, 2014, s. 262-272Konferansepaper, Publicerat paper (Fagfellevurdert)
    sted, utgiver, år, opplag, sider
    New York: ACM Press, 2014
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-212778 (URN)978-1-4503-2670-4 (ISBN)
    Konferanse
    CGO 2014, February 15-19, Orlando, FL
    Prosjekter
    UPMARC
    Tilgjengelig fra: 2014-02-19 Laget: 2013-12-13 Sist oppdatert: 2018-01-11bibliografisk kontrollert
    3. Multiversioned decoupled access-execute: The key to energy-efficient compilation of general-purpose programs
    Åpne denne publikasjonen i ny fane eller vindu >>Multiversioned decoupled access-execute: The key to energy-efficient compilation of general-purpose programs
    Vise andre…
    2016 (engelsk)Inngår i: Proc. 25th International Conference on Compiler Construction, New York: ACM Press, 2016, s. 121-131Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    Computer architecture design faces an era of great challenges in an attempt to simultaneously improve performance and energy efficiency. Previous hardware techniques for energy management become severely limited, and thus, compilers play an essential role in matching the software to the more restricted hardware capabilities. One promising approach is software decoupled access-execute (DAE), in which the compiler transforms the code into coarse-grain phases that are well-matched to the Dynamic Voltage and Frequency Scaling (DVFS) capabilities of the hardware. While this method is proved efficient for statically analyzable codes, general purpose applications pose significant challenges due to pointer aliasing, complex control flow and unknown runtime events. We propose a universal compile-time method to decouple general-purpose applications, using simple but efficient heuristics. Our solutions overcome the challenges of complex code and show that automatic decoupled execution significantly reduces the energy expenditure of irregular or memory-bound applications and even yields slight performance boosts. Overall, our technique achieves over 20% on average energy-delay-product (EDP) improvements (energy over 15% and performance over 5%) across 14 bench-marks from SPEC CPU 2006 and Parboil benchmark suites, with peak EDP improvements surpassing 70%.

    sted, utgiver, år, opplag, sider
    New York: ACM Press, 2016
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-283200 (URN)10.1145/2892208.2892209 (DOI)000389808800012 ()9781450342414 (ISBN)
    Konferanse
    CC 2016, March 17–18, Barcelona, Spain
    Prosjekter
    UPMARC
    Tilgjengelig fra: 2016-03-17 Laget: 2016-04-11 Sist oppdatert: 2018-12-03bibliografisk kontrollert
    4. Building Heterogeneous Unified Virtual Memories (UVMs) without the Overhead
    Åpne denne publikasjonen i ny fane eller vindu >>Building Heterogeneous Unified Virtual Memories (UVMs) without the Overhead
    2016 (engelsk)Inngår i: ACM Transactions on Architecture and Code Optimization (TACO), ISSN 1544-3566, E-ISSN 1544-3973, Vol. 13, nr 1, artikkel-id 1Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    This work proposes a novel scheme to facilitate heterogeneous systems with unified virtual memory. Research proposals implement coherence protocols for sequential consistency (SC) between central processing unit (CPU) cores and between devices. Such mechanisms introduce severe bottlenecks in the system; therefore, we adopt the heterogeneous-race-free (HRF) memory model. The use of HRF simplifies the coherency protocol and the graphics processing unit (GPU) memory management unit (MMU). Our protocol optimizes CPU and GPU demands separately, with the GPU part being simpler while the CPU is more elaborate and latency aware. We achieve an average 45% speedup and 45% energy-delay product reduction (20% energy) over the corresponding SC implementation.

    Emneord
    Multicore; heterogeneous coherence; GPU MMU design; virtual coherence protocol; directory-less protocol
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-295765 (URN)10.1145/2889488 (DOI)000373904600001 ()
    Prosjekter
    UPMARC
    Forskningsfinansiär
    EU, FP7, Seventh Framework Programme, FP7-ICT-288653EU, European Research Council, TIN2012-38341-C04-03
    Tilgjengelig fra: 2016-04-05 Laget: 2016-06-09 Sist oppdatert: 2017-11-30bibliografisk kontrollert
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  • 180.
    Koukos, Konstantinos
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Black-Schaffer, David
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Spiliopoulos, Vasileios
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Kaxiras, Stefanos
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Towards more efficient execution: a decoupled access-execute approach2013Inngår i: Proc. 27th ACM International Conference on Supercomputing, New York: ACM Press, 2013, s. 253-262Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The end of Dennard scaling is expected to shrink the range of DVFS in future nodes, limiting the energy savings of this technique. This paper evaluates how much we can increase the effectiveness of DVFS by using a software decoupled access-execute approach. Decoupling the data access from execution allows us to apply optimal voltage-frequency selection for each phase and therefore improve energy efficiency over standard coupled execution.

    The underlying insight of our work is that by decoupling access and execute we can take advantage of the memory-bound nature of the access phase and the compute-bound nature of the execute phase to optimize power efficiency, while maintaining good performance. To demonstrate this we built a task based parallel execution infrastructure consisting of: (1) a runtime system to orchestrate the execution, (2) power models to predict optimal voltage-frequency selection at runtime, (3) a modeling infrastructure based on hardware measurements to simulate zero-latency, per-core DVFS, and (4) a hardware measurement infrastructure to verify our model's accuracy.

    Based on real hardware measurements we project that the combination of decoupled access-execute and DVFS has the potential to improve EDP by 25% without hurting performance. On memory-bound applications we significantly improve performance due to increased MLP in the access phase and ILP in the execute phase. Furthermore we demonstrate that our method can achieve high performance both in presence or absence of a hardware prefetcher.

    Fulltekst (pdf)
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  • 181.
    Koukos, Konstantinos
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Black-Schaffer, David
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Spiliopoulos, Vasileios
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Kaxiras, Stefanos
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Towards Power Efficiency on Task-Based, Decoupled Access-Execute Models2013Inngår i: PARMA 2013, 4th Workshop on Parallel Programming and Run-Time Management Techniques for Many-core Architectures, 2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This work demonstrates the potential of hardware and software optimization to improve theeffectiveness of dynamic voltage and frequency scaling (DVFS). For software, we decouple data prefetch (access) and computation (execute) to enable optimal DVFS selectionfor each phase. For hardware, we use measurements from state-of-the-art multicore processors to accurately model the potential of per-core, zero-latency DVFS. We demonstrate that the combinationof decoupled access-execute and precise DVFS has the potential to decrease EDP by 25-30% without reducing performance.

    The underlying insight in this work is that by decoupling access and execute we can take advantageof the memory-bound nature of the access phase and the compute-bound nature of the execute phase to optimize power efficiency. For the memory-bound access phase, where we prefetch data into the cachefrom main memory, we can run at a reduced frequency and voltage without hurting performance. Thereafter, the execute phase can run much faster, thanks to the prefetching of the access phase, and achieve higher performance. This decoupled program behavior allows us to achieve more effective use of DVFS than standard coupled executions which mix data access and compute.

    To understand the potential of this approach, we measure application performance and power consumption on a modern multicore system across a range of frequencies and voltages. From this data we build a model that allows us to analyze the effects of per-core, zero-latency DVFS. The results of this work demonstrate the significant potential for finer-grain DVFS in combination with DVFS-optimized software.

    Fulltekst (pdf)
    fulltext
  • 182.
    Koukos, Konstantinos
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Ros, Alberto
    Hagersten, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Kaxiras, Stefanos
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Building Heterogeneous Unified Virtual Memories (UVMs) without the Overhead2016Inngår i: ACM Transactions on Architecture and Code Optimization (TACO), ISSN 1544-3566, E-ISSN 1544-3973, Vol. 13, nr 1, artikkel-id 1Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This work proposes a novel scheme to facilitate heterogeneous systems with unified virtual memory. Research proposals implement coherence protocols for sequential consistency (SC) between central processing unit (CPU) cores and between devices. Such mechanisms introduce severe bottlenecks in the system; therefore, we adopt the heterogeneous-race-free (HRF) memory model. The use of HRF simplifies the coherency protocol and the graphics processing unit (GPU) memory management unit (MMU). Our protocol optimizes CPU and GPU demands separately, with the GPU part being simpler while the CPU is more elaborate and latency aware. We achieve an average 45% speedup and 45% energy-delay product reduction (20% energy) over the corresponding SC implementation.

    Fulltekst (pdf)
    fulltext
  • 183.
    Kumar, Rakesh
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik. Univ Edinburgh, Edinburgh, Midlothian, Scotland.
    Grot, Boris
    Univ Edinburgh, Edinburgh, Midlothian, Scotland.
    Nagarajan, Vijay
    Univ Edinburgh, Edinburgh, Midlothian, Scotland.
    Blasting Through The Front-End Bottleneck With Shotgun2018Inngår i: ACM Sigplan Notices, 2018, Vol. 53, nr 2, s. 30-42Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The front-end bottleneck is a well-established problem in server workloads owing to their deep software stacks and large instruction working sets. Despite years of research into effective L1-I and BTB prefetching, state-of-the-art techniques force a trade-off between performance and metadata storage costs. This work introduces Shotgun, a BTB-directed front-end prefetcher powered by a new BTB organization that maintains a logical map of an application's instruction footprint, which enables high-efficacy prefetching at low storage cost. To map active code regions, Shotgun precisely tracks an application's global control flow (e.g., function and trap routine entry points) and summarizes local control flow within each code region. Because the local control flow enjoys high spatial locality, with most functions comprised of a handful of instruction cache blocks, it lends itself to a compact region-based encoding. Meanwhile, the global control flow is naturally captured by the application's unconditional branch working set (calls, returns, traps). Based on these insights, Shotgun devotes the bulk of its BTB capacity to branches responsible for the global control flow and a spatial encoding of their target regions. By effectively capturing a map of the application's instruction footprint in the BTB, Shotgun enables highly effective BTB-directed prefetching. Using a storage budget equivalent to a conventional BTB, Shotgun outperforms the state-of-the-art BTB-directed front-end prefetcher by up to 14% on a set of varied commercial workloads.

  • 184.
    Kähkönen, Christian
    Högskolan på Gotland, Institutionen för speldesign, teknik och lärande.
    How to create a 3D character model for a pre-existing live action film, that matches the characteristics of the intellectual property and the visual style of the chosen film2012Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    My aim is to find out how to create a 3d character model for a pre-existing live action film, give this character characteristics that match the intellectual property and follow the visual style of the chosen film. For my example in this degree project, I chose Disney's adaption of John Carter of Mars.

    I used my own pipeline, which is a collection of work methods from different artists, for the creation of the example 3d character model. Though with a limit of bringing the model through the first two steps, as I focus on the constraint of this thesis work.

    In order to create this model, I researched the universe of John Carter, and the visual style of the film, and from that knowledge I designed a character to create a 3d model of.

    The finished 3d character model of this degree project was then compared to models from the production of John Carter of Mars, both by the author and through a survey to evaluate the result.

    Fulltekst (pdf)
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  • 185.
    Lampa, Samuel
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    Alvarsson, Jonathan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    Spjuth, Ola
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Towards agile large-scale predictive modelling in drug discovery with flow-based programming design principles2016Inngår i: Journal of Cheminformatics, ISSN 1758-2946, E-ISSN 1758-2946, Vol. 8, artikkel-id 67Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Predictive modelling in drug discovery is challenging to automate as it often contains multiple analysis steps and might involve cross-validation and parameter tuning that create complex dependencies between tasks. With large-scale data or when using computationally demanding modelling methods, e-infrastructures such as high-performance or cloud computing are required, adding to the existing challenges of fault-tolerant automation. Workflow management systems can aid in many of these challenges, but the currently available systems are lacking in the functionality needed to enable agile and flexible predictive modelling. We here present an approach inspired by elements of the flow-based programming paradigm, implemented as an extension of the Luigi system which we name SciLuigi. We also discuss the experiences from using the approach when modelling a large set of biochemical interactions using a shared computer cluster.

    Fulltekst (pdf)
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  • 186.
    Lampka, Kai
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    With Real-time Performance Analysis and Monitoring to Timing Predictable Use of Multi-core Architectures2013Inngår i: Runtime Verification, Springer Berlin/Heidelberg, 2013, s. 400-402Konferansepaper (Fagfellevurdert)
  • 187.
    Lampka, Kai
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik. Elektrobit Automot, Erlangen, Germany..
    Bondorf, Steffen
    Univ Kaiserslautern, Distributed Comp Syst DISCO Lab, Kaiserslautern, Germany..
    Schmitt, Jens B.
    Univ Kaiserslautern, Distributed Comp Syst DISCO Lab, Kaiserslautern, Germany..
    Guan, Nan
    Hong Kong Polytech Univ, Dept Comp, Hong Kong, Hong Kong, Peoples R China..
    Wang, Yi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Generalized Finitary Real-Time Calculus2017Inngår i: IEEE INFOCOM 2017 - IEEE Conference on Computer Communications, IEEE, 2017Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Real-time Calculus (RTC) is a non-stochastic queuing theory to the worst-case performance analysis of distributed real-time systems. Workload as well as resources are modelled as piece-wise linear, pseudo-periodic curves and the system under investigation is modelled as a sequence of algebraic operations over these curves. The memory footprint of computed curves increases exponentially with the sequence of operations and RTC may become computationally infeasible fast. Recently, Finitary RTC has been proposed to counteract this problem. Finitary RTC restricts curves to finite input domains and thereby counteracts the memory demand explosion seen with pseudo periodic curves of common RTC implementations. However, the proof to the correctness of Finitary RTC specifically exploits the operational semantic of the greed processing component (GPC) model and is tied to the maximum busy window size. This is an inherent limitation, which prevents a straight-forward generalization. In this paper, we provide a generalized Finitary RTC that abstracts from the operational semantic of a specific component model and reduces the finite input domains of curves even further. The novel approach allows for faster computations and the extension of the Finitary RTC idea to a much wider range of RTC models.

  • 188.
    Lampka, Kai
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Siegle, Markus
    University of the Federal Forces Germany.
    A Symbolic Approach to the Analysis of Multi-Formalism Markov Reward Models2013Inngår i: Theory and Application of Multi-Formalism Modeling, Pennsylvania: IGI Global, 2013, 1Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    With complex systems and complex requirements being a challenge that designers must face to reach quality results, multi-formalism modeling offers tools and methods that allow modelers to exploit the benefits of different techniques in a general framework intended to address these challenges.

    Theory and Application of Multi-Formalism Modeling boldly explores the importance of this topic by gathering experiences, theories, applications, and solutions from diverse perspectives of those involved with multi-formalism modeling. Professionals, researchers, academics, and students in this field will be able to critically evaluate the latest developments and future directions of multi-formalism research.

  • 189.
    Lantz, Olof
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Tillämpad kärnfysik.
    Virtualiserad testmiljö: Utvärdering av virtualiseringsprogramvaror2014Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    Virtualization has increasingly been adopted in the last decade and the usages of virtualized environments are going to be an important part of how computers are used in the nearby future. There are a lot of advantages with virtualization and different methods have been developed to make it as efficient as possible.

    Forsmarks Kraftgrupp were interested in the possibility of taking advantage of virtualization in their testing environment.

    In this report, hypervisors of type 1 and type 2 and containers have been evaluated to determine which method and what program is preferable on a server cluster of four HP ProLiant DL380 Generation 4. Because of the hardware specifications of the DL380, focus has been on virtualization programs that do not require hardware assisted virtualization.

    The results show that it is possible to use some of the type 2 hypervisors on the HP ProLiant DL380 Generation 4. The suggested virtualization programs are VMware Workstation or Oracle VirtualBox. 

    Fulltekst (pdf)
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  • 190.
    Lind, Simon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för biologisk grundutbildning.
    Distributed Ensemble Learning With Apache Spark2016Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
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  • 191.
    Lindén, Jonatan
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Jonsson, Bengt
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    A Skiplist-based Concurrent Priority Queue with Minimal Memory Contention2013Inngår i: OPODIS 2013: 17th International Conference On Principles Of DIstributed Systems / [ed] Roberto Baldoni, Nicolas Nisse, Maarten van Steen, Berlin: Springer Berlin/Heidelberg, 2013, s. 206-220Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Priority queues are fundamental to many multiprocessor  applications. Several priority queue algorithms based on skiplists  have been proposed, as skiplists allow concurrent accesses to  different parts of the data structure in a simple way. However, for  priority queues on multiprocessors, an inherent bottleneck is the  operation that deletes the minimal element. We present a  linearizable, lock-free, concurrent priority queue algorithm, based  on skiplists, which minimizes the contention for shared memory that  is caused by the DeleteMin operation. The main idea is to  minimize the number of global updates to shared memory that are  performed in one DeleteMin. In comparison with other  skiplist-based priority queue algorithms, our algorithm achieves a  30 - 80% improvement.

  • 192.
    Ljungberg, Jens
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära.
    Evaluation of a Centralized Substation Protection and Control System for HV/MV Substation2018Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Today, conventional substation protection and control systems are of a widely distributed character. One substation can easily have as many as 50 data processing points that all perform similar algorithms on voltage and current data. There is also only limited communication between protection devices, and each device is only aware of the bay in which it is installed. With the intent of implementing a substation protection system that is simpler, more efficient and better suited for future challenges, Ellevio AB implemented a centralized system in a primary substation in 2015. It is comprised of five components that each handle one type of duty: Data processing, communication, voltage measurements, current measurements and breaker control. Since its implementation, the centralized system has been in parallel operation with the conventional, meaning that it performs station wide data acquisition, processing and communication, but is unable to trip the station breakers. The only active functionality of the centralized system is the voltage regulation. This work is an evaluation of the centralized system and studies its protection functionality, voltage regulation, fault response and output signal correlation with the conventional system. It was found that the centralized system required the implementation of a differential protection function and protection of the capacitor banks and busbar coupling to provide protection equivalent to that of the conventional system. The voltage regulation showed unsatisfactory long regulation time lengths, which could have been a result of low time resolution. The fault response and signal correlation were deemed satisfactory.

    Fulltekst (pdf)
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  • 193.
    Lundstedt, Magnus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten.
    Implementation and Evaluation of Image Retrieval Method Utilizing Geographic Location Metadata2009Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Multimedia retrieval systems are very important today with millions of content creators all over the world generating huge multimedia archives. Recent developments allows for content based image and video retrieval. These methods are often quite slow, especially if applied on a library of millions of media items.

    In this research a novel image retrieval method is proposed, which utilizes spatial metadata on images. By finding clusters of images based on their geographic location, the spatial metadata, and combining this information with existing content- based image retrieval algorithms, the proposed method enables efficient presentation of high quality image retrieval results to system users.

    Clustering methods considered include Vector Quantization, Vector Quantization LBG and DBSCAN. Clustering was performed on three different similarity measures; spatial metadata, histogram similarity or texture similarity.

    For histogram similarity there are many different distance metrics to use when comparing histograms. Euclidean, Quadratic Form and Earth Mover’s Distance was studied. As well as three different color spaces; RGB, HSV and CIE Lab. 

    Fulltekst (pdf)
    Multimedia Retrieval Thesis - Magnus Lundstedt
  • 194.
    Löscher, Andreas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    Tsiftes, Nicolas
    Voigt, Thiemo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Handziski, Vlado
    Efficient and Flexible Sensornet Checkpointing2014Inngår i: Wireless Sensor Networks, volume 8354, 2014, s. -65Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Developing sensornet software is difficult partly because ofthe limited visibility of the system state of deployed nodes. Sensor-net checkpointing is a method that allows developers to save and restore full system state of nodes. We present four extensions to sensornetcheckpointing—compression, binary diffs, selective checkpointing, and checkpoint inspection—that reduce the time required for checkpointing operations considerably, and improve the granularity at which system state can be examined and manipulated down to the variable level. We show through an experimental evaluation that the checkpoint sizes can be reduced by 70%-93%, and the time can be reduced by at least 50% because of these improvements. The reduced time and increased granularity benefits multiple checkpointing use cases, including automated testing, network visualization, and software debugging.

  • 195.
    Mahmood, Khalid
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    Orsborn, Kjell
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    Risch, Tore
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    Comparison of NoSQL Datastores for Large Scale Data Stream Log Analytics2019Inngår i: 2019 IEEE International Conference on Smart Computing (SMARTCOMP), IEEE , 2019, s. 478-480Konferansepaper (Fagfellevurdert)
    Abstract [en]

    With the advent of cyber-physical systems, industrial internet of things (IIoT) and industrial analytics numerous application scenarios have emerged where business and mission-critical decisions depend upon large scale analysis of data in form of sensor streams. However, large volumes of sensor stream data generated at high frequency pose substantial challenges for existing scalable data analysis techniques requiring the use of high-performance distributed datastores. This work covers in-depth performance comparison of three principal categories of distributed state-of-the-art NoSQL datastores by evaluating their applicability and efficiency for large-scale analysis of sensor logs from real-world hydraulic power systems. One central datastore is selected from each of the three principal categories of NoSQL datastores: MongoDB from the document store, Cassandra from the column store and Redis from the distributed main memory key-value store to be included in the performance evaluation. Understanding the differences and behavior of this type of systems are crucial for optimizing application performance. Key insights from this work can serve as a basis for an improved understanding of the applicability of NoSQL datastores in systems for large scale data stream analysis. This will be important for supporting data analytics in IIoT applications as found in monitoring and control of Power plants, Smart Cities, Transportation systems, Environmental and Health monitoring, etc.

  • 196. Maioli, Andrea
    et al.
    Mottola, Luca
    Politecnico di Milano, Italy; RI.SE SICS, Sweden.
    Alizai, Muhammad Hamad
    Siddiqui, Junaid Haroon
    On Intermittence Bugs in the Battery-less Internet of Things2019Inngår i: LCTES 2019 Proceedings of the 20th ACM SIGPLAN/SIGBED International Conference on Languages, Compilers, and Tools for Embedded Systems, 2019, s. 203-207Konferansepaper (Fagfellevurdert)
    Fulltekst (pdf)
    fulltext
  • 197.
    Mann, I. R.
    et al.
    Univ Alberta, Dept Phys, Edmonton, AB, Canada.
    Di Pippo, S.
    United Nations Off Vienna, Off Outer Space Affairs, Vienna, Austria.
    Opgenoorth, Hermann Josef
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutet för rymdfysik, Uppsalaavdelningen. Univ Leicester, Dept Phys & Astron, Leicester, Leics, England.
    Kuznetsova, M.
    NASA, Goddard Spaceflight Ctr, Greenbelt, MD USA.
    Kendall, D. J.
    Canadian Space Agcy, St Hubert, PQ, Canada.
    International Collaboration Within the United Nations Committee on the Peaceful Uses of Outer Space: Framework for International Space Weather Services (2018-2030)2018Inngår i: Space Weather: The international journal of research and applications, ISSN 1542-7390, E-ISSN 1542-7390, Vol. 16, nr 5, s. 428-433Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    Severe space weather is a global threat that requires a coordinated global response. In this Commentary, we review some previous successful actions supporting international coordination between member states in the United Nations (UN) context and make recommendations for a future approach. Member states of the UN Committee on the Peaceful Uses of Outer Space (COPUOS) recently approved new guidelines related to space weather under actions for the long-term sustainability of outer space activities. This is to be followed by UN Conference on the Exploration and Peaceful Uses of Outer Space (UNISPACE)+50, which will take place in June 2018 on the occasion of the fiftieth anniversary of the first UNISPACE I held in Vienna in 1968. Expanded international coordination has been proposed within COPUOS under the UNISPACE+50 process, where priorities for 2018-2030 are to be defined under Thematic Priority 4: Framework for International Space Weather Services. The COPUOS expert group for space weather has proposed the creation of a new International Coordination Group for Space Weather be implemented as part of this thematic priority. This coordination group would lead international coordination between member states and across international stakeholders, monitor progress against implementation of guidelines and best practices, and promote coordinated global efforts in the space weather ecosystem spanning observations, research, modeling, and validation, with the goal of improved space weather services. We argue that such improved coordination at the international policy level is essential for increasing global resiliency against the threats arising from severe space weather.

  • 198.
    Mohammedsalih, Salah
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Institutionen för informatik och media, Människa-datorinteraktion.
    Mobile Journalism: Using smartphone in journalistic work2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Mobile phones have had a drastic influence on media production, by providing a ubiquitous connection. This revolution has come about when smartphone turned into a powerful tool to do almost all the production-related work that was done previously by specialized equipment and computers. This has encouraged ordinary individuals to involve in media work and emerging the phenomenon of mobile journalism, where citizens and individuals can engage in journalism work carry out a job that was supposed to be done only by journalists for a long time ago. We are talking about hundreds of thousands of prosumers and amateurs who are making and covering news by their smartphones and contributing to journalism work. This has become particularly apparent in relation to reporting from remote and risky areas, where journalists cannot reach easily or may not arrive on time while important events occur. This was obvious during the Arab-spring - The role of smartphones in feeding both social media and traditional media with instant photos and videos taken by protesters themselves. This thesis focuses on the role of the smartphone in facilitating the work of journalists.

    As a part of the literature review, the author has gone through many texts, watched videos and listened to radio shows with journalists and workers in media spheres, in which journalists talk about their own experience with practicing mobile journalism. Then from a phenomenological perspective and framework the experience of technology and user aspects of mobile journalism are investigated. As the aim of this thesis is not to validate a hypothesis or a theory, a qualitative research method is used to come to an evaluation and explanation of the phenomenon of using mobile in journalism. For that purpose, several qualitative methods have been used to collect data such as auto-ethnography, observation, interviews and focus groups. The data are collected mainly from Kurdistan region in northern Iraq where journalists were covering news of war in dangerous and risky battle fields.  

    The findings from the results showed that the main factors that make smartphones powerful tools for journalists are: the low budget required for acquiring a smartphone compared to expensive equipment used in traditional media, the freedom and independence that a mobile can give to a journalist, the design aspects which provide a pocket-size tool with unsuspiciousness feature that make it possible to be carried and used even in areas where journalistic work is not allowed. The ubiquity feature of mobile has helped to cover news in areas where traditional media cannot be existing or cannot reach easily. The ability of individuals to obtain a smartphone in one hand and the universal design of mobile in another hand have helped to be used in journalism work by many people with no necessary training courses. This situation has created a good opportunity for media institutions and TV stations to expand their correspondents’ network all over the countries.

    Fulltekst (pdf)
    Mobile Journalism
  • 199.
    Mohaqeqi, Morteza
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Abdullah, Jakaria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Ekberg, Pontus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Yi, Wang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Refinement of workload models for engine controllers by state space partitioning2017Inngår i: 29th Euromicro Conference on Real-Time Systems: ECRTS 2017, Dagstuhl, Germany: Leibniz-Zentrum für Informatik , 2017, s. 11:1-22Konferansepaper (Fagfellevurdert)
  • 200.
    Mottola, Luca
    et al.
    SICS and Politecnico di Milano.
    Voigt, Thiemo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Picco, G. P.
    Univ of Trento.
    Electronically-switched Directional Antennas for Wireless Sensor Networks: A Full-stack Evaluation2013Inngår i: IEEE SECON, 2013Konferansepaper (Fagfellevurdert)
123456 151 - 200 of 276
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