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  • 301.
    Börstler, Jürgen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Killer Examples Workshop: Expression of Interest2005Ingår i: 4th OOPSLA Killer Examples Workshop, 2005Konferensbidrag (Övrigt vetenskapligt)
  • 302.
    Börstler, Jürgen
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Institutionen för datavetenskap.
    Object-Oriented Analysis and Design Through Scenario Role-Play2004Rapport (Övrigt vetenskapligt)
  • 303.
    Börstler, Jürgen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Objektorientiertes Programmieren--Machen wir irgendwas falsch?2007Ingår i: Proceedings INFOS07, 2007, s. 9-20Konferensbidrag (Refereegranskat)
  • 304.
    Börstler, Jürgen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Proceedings of the Sixth Conference on Software Engineering Research and Practice in Sweden2006Konferensmeddelanden, proceedings (Refereegranskat)
  • 305.
    Börstler, Jürgen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Tenth workshop on pedagogies and tools for the teaching and learning of object-oriented concepts2007Ingår i: Object-oriented technology: ECOOP 2006 workshop reader / [ed] Mario Südholt & Charles Consel, Berlin: Springer Berlin/Heidelberg, 2007, s. 147-157Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    This report summarizes the results of the tenth workshop on pedagogies and tools for the teaching and learning of object-oriented concepts. The focus of this year’s workshop was on examples, modelling and abstraction. Participants agreed that carefully developed scaffolded examples are a key element for learning to program. For the teaching of modelling and abstraction this area, however, seems badly neglected. The workshop gathered 12 participants, all from academia, from 10 different countries.

  • 306.
    Börstler, Jürgen
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Bay, Omer Faruk
    Baturay, Meltem
    Trapp, Sonja
    Heintz, Matthias
    Weber, Sebastian
    embed4Auto-A PLE for Software Modelling2010Ingår i: ITICSE 2010: proceedings of the 2010 ACM SIGCSE annual conference on innovation and technology in computer science education, Association for Computing Machinery (ACM), 2010, s. 322-322Konferensbidrag (Refereegranskat)
    Abstract [en]

    We have developed courseware for UML/SysML modelling based on the needs of the European embedded/automotive industry. The courseware supports interactive modelling exercises. First evaluations show promising results.

  • 307.
    Börstler, Jürgen
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Caspersen, Michael E.
    Nordström, Marie
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Beauty and the Beast--Toward a Measurement Framework for Example Program Quality2007Rapport (Övrigt vetenskapligt)
  • 308.
    Börstler, Jürgen
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Dranidis, Dimitris
    Ramollari, Ervin
    Trapp, Sonja
    Heintz, Matthias
    Weber, Sebastian
    Sharing and discussing UML modeling exercises in a PLE2010Ingår i: ITICSE 2010: proceedings of the 2010 ACM annual conference on innovation and technology in computer science education, Association for Computing Machinery (ACM), 2010, s. 301-301Konferensbidrag (Refereegranskat)
    Abstract [en]

    We present courseware for UML/SysML modelling that supports collaborative learning at a distance. Learners can solve interactive modelling exercises and discuss their solutions. First evaluations show promising results.

  • 309.
    Börstler, Jürgen
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Hadar, Irit
    Eleventh workshop on pedagogies and tools for the teaching and learning of object-oriented concepts2008Ingår i: Object-oriented technology. ECOOP 2007 workshop reader: ECOOP 2007 workshops, Berlin, Germany, July 30-31, 2007, final reports / [ed] Michael Cebulla, Berlin: Springer , 2008, s. 182-192Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    This report summarizes the results of the eleventh workshop on pedagogies and tools for the teaching and learning of object-oriented concepts. The focus of this year's workshop was on desirable properties of examples and the usage of simple tools. The workshop gathered 17 participants, all from academia, from 7 different countries.

  • 310.
    Börstler, Jürgen
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Hall, Mark S
    University of Wisconsin.
    Nordström, Marie
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Paterson, James H
    Glasgow Caledonian University.
    Sanders, Kate
    Rhode Island College.
    Schulte, Carsten
    Freie Universität Berlin.
    Thomas, Lynda
    Aberystwyth University.
    An evaluation of object oriented example programs in introductory programming textbooks2009Ingår i: SIGCSE Bulletin inroads, ISSN 0097-8418, Vol. 41, nr 4, s. 126-143Artikel i tidskrift (Refereegranskat)
  • 311.
    Börstler, Jürgen
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Michiels, Isabel
    ECOOP 2004 Workshop Report: Eigth Workshop on Pedagogies and Tools for the Teaching and Learning of Object-Oriented Concepts2004Ingår i: Object-Oriented Technology: ECOOP 2004 Workshop Reader, Springer , 2004, s. 36-48Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 312.
    Börstler, Jürgen
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Michiels, Isabel
    Bruce, Kim
    Lindholm, Morten
    Ninth Workshop on Pedagogies and Tools for the Teaching and Learning of Object-Oriented Concepts2006Ingår i: ECOOP 2005 Workshop Reader, Springer , 2006Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 313.
    Börstler, Jürgen
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Nordström, Marie
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Kallin Westin, Lena
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Moström, Jan Erik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Christensen, Henrik B.
    Bennedsen, Jens
    An Evaluation Instrument for Object-Oriented Example Programs for Novices2008Rapport (Övrigt vetenskapligt)
  • 314.
    Börstler, Jürgen
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Nordström, Marie
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Kallin Westin, Lena
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Moström, Jan Erik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Eliasson, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Transitioning to OOP/Java: A never ending story2008Ingår i: Reflections on the teaching of programming, Springer , 2008, s. 80-97Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 315.
    Börstler, Jürgen
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Schulte, Carsten
    Teaching Object Oriented Modelling with CRC Cards and Roleplaying Games2005Ingår i: Proceedings of the 8th IFIP World Conference on Computing in Education, 2005Konferensbidrag (Refereegranskat)
  • 316.
    Camillo, Frédéric
    et al.
    University of Toulouse / ENSEEIHT.
    Caron, Eddy
    University of Lyon / École Normale Supérieure de Lyon.
    Guivarch, Ronan
    University of Toulouse / ENSEEIHT.
    Hurault, Aurélie
    University of Toulouse / ENSEEIHT.
    Klein, Cristian
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Pérez, Christian
    University of Lyon / INRIA.
    Resource Management Architecture for Fair Scheduling of Optional Computations2013Ingår i: 2013 Eighth International Conference on P2P, Parallel, Grid, Cloud and Internet Computing: 3PGCIC 2013 / [ed] Fatos Xhafa, Leonard Barolli, Dritan Nace, Salvatore Vinticinque and Alain Bui, IEEE Computer Society, 2013, s. 113-120Konferensbidrag (Refereegranskat)
    Abstract [en]

    Most HPC platforms require users to submit a pre-determined number of computation requests (also called jobs). Unfortunately, this is cumbersome when some of the computations are optional, i.e., they are not critical, but their completion would improve results. For example, given a deadline, the number of requests to submit for a Monte Carlo experiment is difficult to choose. The more requests are completed, the better the results are, however, submitting too many might overload the platform. Conversely, submitting too few requests may leave resources unused and misses an opportunity to improve the results.

    This paper introduces and solves the problem of scheduling optional computations. An architecture which auto-tunes the number of requests is proposed, then implemented in the DIET GridRPC middleware. Real-life experiments show that several metrics are improved, such as user satisfaction, fairness and the number of completed requests. Moreover, the solution is shown to be scalable.

  • 317.
    Carlquist, Joel
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Evaluation of Teaching Evolution Using Evolutionary Algorithms in a 2D Physics Sandbox2013Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Evolution and Darwin’s theory is the most important scientific theories for understanding human genealogy and our heritage. However, the theory of evolution has been continuously challenged and denied, without conclusive evidence against it. To show both the possibilities and power of evolution we are able to use evolutionary algorithms, a method used in computing science that is inspired by evolution. This is shown possible by developing and analysing a tool created for the 2D physics sandbox Algodoo. The tool uses evolutionary algorithms for improving objects. This tool is evaluated in two parts, a user survey and an analysis of the results of the evolution, where both indicate that while the tool does not quite reach the goals set, with further development the requirements will be met. The thesis also contains an overview of evolutionary algorithms and methods used in these, especially the methods used by Karl Sims in his work on evolved creatures. His work has been a great inspiration to this thesis.

  • 318.
    Cavallin, Kristoffer
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Institutionen för datavetenskap.
    Svensson, Peter
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Institutionen för datavetenskap.
    Semi-Autonomous,Teleoperated Search and Rescue Robot2009Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The interest in robots in the urban search and rescue (USAR) field has increased the last two decades. The idea is to let robots move into places where human rescue workers cannot or, due to high personal risks, should not enter.In this thesis project, an application is constructed with the purpose of teleoperating a simple robot. This application contains a user interface that utilizes both autonomous and semi-autonomous functions, such as search, explore and point-and-go behaviours. The purpose of the application is to work with USAR principles in a refined and simplified environment, and thereby increase the understanding for these principles and how they interact with each other. Furthermore, the thesis project reviews the recent and the current status of robots in USAR applications and use of teleoperation and semi-autonomous robots in general. Some conclusions that are drawn towards the end of the thesis are that the use of robots, especially in USAR situations, will continue to increase. As robots and support technology both become more advanced and cheaper by the day, teleoperation and semi-autonomous robots will also be seen in more and more places.

     

  • 319.
    Chaudhry, Naeem Ashfaq
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Automatic Facial Occlusion Detection and Removal2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In our daily life, we are faced with many occluded faces. The occlusion may be from different objects like sunglasses, mufflers, masks, scarves etc. Sometimes, this occlusion is used by the criminal persons to hide their identity from the surroundings. In this thesis, a technique is used to detect the facial occlusion automatically. After detecting the occluded areas, a method for image reconstruction called aPCA (asymmetrical Principal Component Analysis) is used to reconstruct the faces. The entire face is reconstructed using the non occluded area of the face. A database of images of different persons is organized which is used in the process of reconstruction of the occluded images. Experiments were performed to examine the effect of the granularity of the occlusion on the aPCA reconstruction process. The input mask image is divided into different parts, the occlusion for each part is marked and aPCA is applied to reconstruct the faces. This process of image reconstruction takes a lot of processing time so pre-defined eigenspaces are introduced that takes very less processing time with very less quality loss of the reconstructed faces.

  • 320.
    Chaudhry, Tanmay
    et al.
    SimScale GmbH, Germany.
    Doblander, Christoph
    Technische Universität München, Germany.
    Dammer, Anatol
    SimScale GmbH, Germany.
    Klein, Cristian
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Jacobsen, Hans-Arno
    Technische Universität München, Germany.
    Retrofitting Admission Control in an Internet-Scale Application2016Rapport (Övrigt vetenskapligt)
    Abstract [en]

    In this paper we propose a methodology to retrofit admission control in an Internet-scale, production application. Admission control requires less effort to improve the availability of an application, in particular when making it scalable is costly. This can occur due to the integration of 3rd-party legacy code or handling large amounts of data, and is further motivated by lean thinking, which argues for building a minimum viable product to discover customer requirements.

    Our main contribution consists in a method to generate an amplified workload, that is realistic enough to test all kinds of what-if scenarios, but does not require an exhaustive transition matrix. This workload generator can then be used to iteratively stress-test the application, identify the next bottleneck and add admission control.

    To illustrate the usefulness of the approach, we report on our experience with adding admission control within SimScale, a Software-as-a-Service start-up for engineering simulations, that already features 50,000 users.

  • 321. Chaudhry, Tanmay
    et al.
    Doblander, Christoph
    Dammer, Anatol
    Klein, Cristian
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Jacobsen, Hans-Arno
    Retrofitting Admission Control in an Internet-Scale Application2016Rapport (Övrigt vetenskapligt)
    Abstract [en]

    In this paper we propose a methodology to retrofit admission control in an Internet-scale, production application. Admission control requires less effort to improve the availability of an application, in particular when making it scalable is costly. This can occur due to the integration of 3rd-party legacy code or handling large amounts of data, and is further motivated by lean thinking, which argues for building a minimum viable product to discover customer requirements.

    Our main contribution consists in a method to generate an amplified workload, that is realistic enough to test all kinds of what-if scenarios, but does not require an exhaustive transition matrix. This workload generator can then be used to iteratively stress-test the application, identify the next bottleneck and add admission control.

    To illustrate the usefulness of the approach, we report on our experience with adding admission control within SimScale, a Software-as-a-Service start-up for engineering simulations, that already features 50,000 users.

  • 322.
    Cheddad, Abbas
    et al.
    Umeå universitet, Medicinska fakulteten, Umeå centrum för molekylär medicin (UCMM).
    Nord, Christoffer
    Umeå universitet, Medicinska fakulteten, Umeå centrum för molekylär medicin (UCMM).
    Hörnblad, Andreas
    Umeå universitet, Medicinska fakulteten, Umeå centrum för molekylär medicin (UCMM).
    Prunskaite-Hyyryläinen, Renata
    Oulu Center for Cell-Matrix Research, Biocenter Oulu, Laboratory of Developmental Biology and Department of Medical Biochemistry and Molecular Biology, Institute of Biomedicine, University of Oulu, Finland.
    Eriksson, Maria
    Umeå universitet, Medicinska fakulteten, Umeå centrum för molekylär medicin (UCMM).
    Georgsson, Fredrik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Vainio, Seppo
    Oulu Center for Cell-Matrix Research, Biocenter Oulu, Laboratory of Developmental Biology and Department of Medical Biochemistry and Molecular Biology, Institute of Biomedicine, University of Oulu, Finland.
    Ahlgren, Ulf
    Umeå universitet, Medicinska fakulteten, Umeå centrum för molekylär medicin (UCMM).
    Improving signal detection in emission optical projection tomography via single source multi-exposure image fusion2013Ingår i: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 21, nr 14, s. 16584-16604Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We demonstrate a technique to improve structural data obtained from Optical Projection Tomography (OPT) using Image Fusion (IF) and contrast normalization. This enables the visualization of molecular expression patterns in biological specimens with highly variable contrast values. In the approach, termed IF-OPT, different exposures are fused by assigning weighted contrasts to each. When applied to projection images from mouse organs and digital phantoms our results demonstrate the capability of IF-OPT to reveal high and low signal intensity details in challenging specimens. We further provide measurements to highlight the benefits of the new algorithm in comparison to other similar methods.

  • 323.
    Cheddad, Abbas
    et al.
    Umeå universitet, Medicinska fakulteten, Umeå centrum för molekylär medicin (UCMM).
    Svensson, Christoffer
    Umeå universitet, Medicinska fakulteten, Umeå centrum för molekylär medicin (UCMM).
    Sharpe, James
    Georgsson, Fredrik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Ahlgren, Ulf
    Umeå universitet, Medicinska fakulteten, Umeå centrum för molekylär medicin (UCMM).
    Image processing assisted algorithms for optical projection tomography2012Ingår i: IEEE Transactions on Medical Imaging, ISSN 0278-0062, E-ISSN 1558-254X, Vol. 31, nr 1, s. 1-15Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Since it was first presented in 2002, optical projection tomography (OPT) has emerged as a powerful tool for the study of biomedical specimen on the mm to cm scale. In this paper, we present computational tools to further improve OPT image acquisition and tomographic reconstruction. More specifically, these methods provide: semi-automatic and precise positioning of a sample at the axis of rotation and a fast and robust algorithm for determination of postalignment values throughout the specimen as compared to existing methods. These tools are easily integrated for use with current commercial OPT scanners and should also be possible to implement in "home made" or experimental setups for OPT imaging. They generally contribute to increase acquisition speed and quality of OPT data and thereby significantly simplify and improve a number of three-dimensional and quantitative OPT based assessments.

  • 324. Chen, Ye
    et al.
    Wang, Aiguo
    Ding, Huitong
    Que, Xia
    Li, Yabo
    An, Ning
    Jiang, Lili
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    A global learning with local preservation method for microarray data imputation2016Ingår i: Computers in Biology and Medicine, ISSN 0010-4825, E-ISSN 1879-0534, Vol. 77, s. 76-89Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Microarray data suffer from missing values for various reasons, including insufficient resolution, image noise, and experimental errors. Because missing values can hinder downstream analysis steps that require complete data as input, it is crucial to be able to estimate the missing values. In this study, we propose a Global Learning with Local Preservation method (GL2P) for imputation of missing values in microarray data. GL2P consists of two components: a local similarity measurement module and a global weighted imputation module. The former uses a local structure preservation scheme to exploit as much information as possible from the observable data, and the latter is responsible for estimating the missing values of a target gene by considering all of its neighbors rather than a subset of them. Furthermore, GL2P imputes the missing values in ascending order according to the rate of missing data for each target gene to fully utilize previously estimated values. To validate the proposed method, we conducted extensive experiments on six benchmarked microarray datasets. We compared GL2P with eight state-of-the-art imputation methods in terms of four performance metrics. The experimental results indicate that GL2P outperforms its competitors in terms of imputation accuracy and better preserves the structure of differentially expressed genes. In addition, GL2P is less sensitive to the number of neighbors than other local learning-based imputation. methods.

  • 325.
    Chiang, David
    et al.
    University of Notre Dame.
    Drewes, Frank
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Gildea, Daniel
    University of Rochester.
    Lopez, Adam
    University of Edinburgh.
    Satta, Giorgio
    University of Padua.
    Weighted DAG automata for semantic graphs2018Ingår i: Computational linguistics - Association for Computational Linguistics (Print), ISSN 0891-2017, E-ISSN 1530-9312, Vol. 44, nr 1, s. 119-186Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Graphs have a variety of uses in natural language processing, particularly as representations of linguistic meaning. A deficit in this area of research is a formal framework for creating, combining, and using models involving graphs that parallels the frameworks of finite automata for strings and finite tree automata for trees. A possible starting point for such a framework is the formalism of directed acyclic graph (DAG) automata, defined by Kamimura and Slutzki and extended by Quernheim and Knight. In this article, we study the latter in depth, demonstrating several new results, including a practical recognition algorithm that can be used for inference and learning with models defined on DAG automata. We also propose an extension to graphs with unbounded node degree and show that our results carry over to the extended formalism.

  • 326.
    Chowdhury, Mabruk
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Institutionen för datavetenskap.
    Development of User Interfaces for Mobile, Context-aware Agenda Tools2010Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Diverging from traditional agenda tools, comes Activity Ace which explores the closest vicinity of the hosting mobile device and responds the activity the user wants to be reminded of. In this thesis we investigate in and mobility means and moreover what evaluation methods exists Ace is used by typing down the activity you want to be reminded of and attaching to it a situational description built of metadata and Boolean conditions. The application will trigger the reminder i.e. the activity to be reminded of when the situational description matches with the device's closest vicinity. Amongst many, we found that core features of a contextaware applications consists of what contextawarenessfor these kinds of applications. Activitypresentation, automatic execution of a service  and misconceptions used in mobility rhetoric such as Furthermore we have learned that usability evaluation methods, therein cooperative evaluation methods provide qualitative information on the design and functionality thus prove to be suitable in evaluation of these kind of applications. By reflecting on these issues, we can better understand the role of contextawareness and mobility in an agenda tool such as Activity Ace. tagging of context to information for later retrieval. We have also clarified commonaccess, any time, anywhere.

  • 327.
    Chunag, Lkhagva
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Object localization strategy for a mobile robot using RFID2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    One of the challenging issues in robotics is to give robots the ability to navigate itself in unknown environment without human help. In this thesis, we explored and evaluated object localization method for a mobile robot using radio-frequency identification (RFID) technology. The workplace included objects with RFID tags, a mobile robot with dual antenna RFID reader and obstacles: chairs, tables and a human. Using RFID reader, we were able to have the mobile robot communicate with the RFID tag to navigate the tagged object.

    This research employed the following methods for navigating a mobile robot and locating objects. First, a mobile robot was implemented as Braitenberg vehicle. It used the received signal strength of the RFID tag to compute instantaneously and produce movement of the wheel and generate suitable motion in order to navigate the object. Second, a mobile robot with directional antenna that collects data about relative direction of the interested RFID tag in its local coordinate system and computes tag positions by taking several measurements for different positions of the robot.

    Our experiment results showed that proposed RFID system can locate an object and can track the movement of a target object in real time. To verify effectiveness of the system we performed several experiments in the workplace.

  • 328.
    Ciegis, Raimondas
    et al.
    Vilnius Gediminas Technical University, Lithuania.
    Henty, David
    University of Edingburg, UK.
    Kågström, Bo
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Högpresterande beräkningscentrum norr (HPC2N).
    Zilinskas, Julius
    Vilnius Gediminas Technical University, Lithuania.
    Parallel Scientific Computing and Optimization: Advances with Applications2009Bok (Övrigt vetenskapligt)
  • 329.
    Cimiano, Philipp
    et al.
    Technical University of Karlsruhe.
    Minock, Michael
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Natural language interfaces: what's the problem? -a data-driven quantitative analysis2010Ingår i: Natural language processing and information systems: 14th International Conference on Applications of Natural Language to Information Systems, NLDB 2009 / [ed] Helmut Horacek, Elisabeth Métais, Rafael Muñoz and Magdalena Wolska, Springer Berlin/Heidelberg, 2010, s. 192-206Konferensbidrag (Refereegranskat)
    Abstract [en]

    While qualitative analyses of the problems involved in building natural language interfaces (NLIs) have been available, a quantitative grounding in empirical data has been missing. We fill this gap by providing a quantitative analysis on the basis of the Geobase dataset. We hope that this analysis can guide further research in NLIs.

  • 330. Conejero, Javier
    et al.
    Caminero, Blanca
    Carrion, Carmen
    Tomas, Luis
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    From volunteer to trustable computing: Providing QoS-aware scheduling mechanisms for multi-grid computing environments2014Ingår i: Future generations computer systems, ISSN 0167-739X, E-ISSN 1872-7115, Vol. 34, s. 76-93Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The exploitation of service oriented technologies, such as Grid computing, is being boosted by the current service oriented economy trend, leading to a growing need of Quality of Service (QoS) mechanisms. However, Grid computing was created to provide vast amounts of computational power but in a best effort way. Providing QoS guarantees is therefore a very difficult and complex task due to the distributed and heterogeneous nature of their resources, specially the volunteer computing resources (e.g., desktop resources). The scope of this paper is to empower an integrated multi QoS support suitable for Grid Computing environments made of either dedicated and volunteer resources, even taking advantage of that fact. The QoS is provided through SLAs by exploiting different available scheduling mechanisms in a coordinated way, and applying appropriate resource usage optimization techniques. It is based on the differentiated use of reservations and scheduling in advance techniques, enhanced with the integration of rescheduling techniques that improve the allocation decisions already made, achieving a higher resource utilization and still ensuring the agreed QoS. As a result, our proposal enhances best-effort Grid environments by providing QoS aware scheduling capabilities. This proposal has been validated by means of a set of experiments performed in a real Grid testbed. Results show how the proposed framework effectively harnesses the specific capabilities of the underlying resources to provide every user with the desired QoS level, while, at the same time, optimizing the resources' usage. (C) 2013 Elsevier B.V. All rights reserved.

  • 331. Confalonieri, Roberto
    et al.
    Nieves, Juan Carlos
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Osorio, Mauricio
    Vazquez-Salceda, Javier
    Dealing with explicit preferences and uncertainty in answer set programming2012Ingår i: Annals of Mathematics and Artificial Intelligence, ISSN 1012-2443, E-ISSN 1573-7470, Vol. 65, nr 2-3, s. 159-198Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we show how the formalism of Logic Programs with Ordered Disjunction (LPODs) and Possibilistic Answer Set Programming (PASP) can be merged into the single framework of Logic Programs with Possibilistic Ordered Disjunction (LPPODs). The LPPODs framework embeds in a unified way several aspects of common-sense reasoning, nonmonotonocity, preferences, and uncertainty, where each part is underpinned by a well established formalism. On one hand, from LPODs it inherits the distinctive feature of expressing context-dependent qualitative preferences among different alternatives (modeled as the atoms of a logic program). On the other hand, PASP allows for qualitative certainty statements about the rules themselves (modeled as necessity values according to possibilistic logic) to be captured. In this way, the LPPODs framework supports a reasoning which is nonmonotonic, preference- and uncertainty-aware. The LPPODs syntax allows for the specification of (1) preferences among the exceptions to default rules, and (2) necessity values about the certainty of program rules. As a result, preferences and uncertainty can be used to select the preferred uncertain default rules of an LPPOD and, consequently, to order its possibilistic answer sets. Furthermore, we describe the implementation of an ASP-based solver able to compute the LPPODs semantics.

  • 332.
    Coquand, Marc
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Evaluating Functional Programming for Software Quality in REST APIs2019Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Defects in Software engineering are a common occurrence. To mitigate defects the developers must create maintainable solutions and strive for good software quality. A maintainable solution is readable, extensible, not error-prone and testable. In order to make them so developers follow a guideline called SOLID principles. These principles are not enforced by the language but relies on the diligence of the developers, meaning there is nothing stopping them from writing unmaintainable code. This study translates these principles to Functional programming to investigate if Functional programming can be used to construct a library for servers that forces the developer to create correct code without incurring costs in maintenance and readability.

  • 333. Corradini, Andrea
    et al.
    Drewes, Frank
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Term graph rewriting and parallel term rewriting2011Ingår i: Proceedings of the 6th International Workshop on Computing with Terms and Graphs: Saarbrücken, Germany, 2nd April / [ed] Rachid Echahed, Open Publishing Association , 2011, s. 3-18Konferensbidrag (Refereegranskat)
    Abstract [en]

    The relationship between Term Graph Rewriting and Term Rewriting is well understood: a single term graph reduction may correspond to several term reductions, due to sharing. It is also known that if term graphs are allowed to contain cycles, then one term graph reduction may correspond to infinitely many term reductions. We stress that this fact can be interpreted in two ways. According to the "sequential interpretation", a term graph reduction corresponds to an infinite sequence of term reductions, as formalized by Kennaway et.al. using strongly converging derivations over the complete metric space of infinite terms. Instead according to the "parallel interpretation" a term graph reduction corresponds to the parallel reduction of an infinite set of redexes in a rational term. We formalize the latter notion by exploiting the complete partial order of infinite and possibly partial terms, and we stress that this interpretation allows to explain the result of reducing circular redexes in several approaches to term graph rewriting.

  • 334.
    Courtois, Julien
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Szumski, Michal
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Georgsson, Fredrik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Irgum, Knut
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Assessing the macroporous structure of monolithic columns by transmission electron microscopy2007Ingår i: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 79, nr 1, s. 335-344Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A set of monolithic stationary phases representing a broad span of monomers and porogens have been characterized directly in their capillary chromatographic format by computational assessment of their pore structure from transmission electron micrographs obtained after in situ embedment of the monoliths in contrast resin, followed by dissolution of the fused-silica tubing, further encasement of the resin-embedded monolith, and microtomy. This technique has been compared to mercury intrusion, a more conventional technique for macroporosity estimation. Supplementing the embedding resin by lead methacrylate gave a negative staining, and the resulting micrographs showed a good contrast between the polymeric monoliths and the embedding resin that allowed studies on the pore formation and polymer development. The technique was also applied to a commercial monolithic silica column.

  • 335.
    Coyne, Adam Kavanagh
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Multi-Modal Teleoperation of a Humanoid Social Robot Initial Evaluation of Control Modalities2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Over previous years numerous social service robots have been show cased by companies and popular media, yet despite seeming on the cusp of becoming mainstream they are still far from entering into everyday use. Artificial intelligence has progress to make before becoming suitable for service robots, and this may be a major cause, however this issue can be mitigated by the implementation of an accessible social robot teleoperation framework that would allow a layperson user to control all of the social faculties of such a robot from a distance. Such a framework would compensate for the shortcomings of an artificial agent by letting control be switched to a human operator in difficult situations. The nature of social teleoperation being multimodal, attention must be brought to the control interface used by the operator; simultaneous use of multiple control modalities may be strenuous depending on the nature of these modalities. This paper details the initial evaluation o fsuch control modalities independently, towards the development of a multimodal teleoperation framework for robot socialisation using these modalities. User testing is employed to compare control schemes for the modalities of Navigation, Gestures, Neck control and Emotion control, using commonly available input equipment with virtual reality. Evaluation is conducted by studying time performance, workload and user preference and feedback; testing is done with a prototype teleoperation framework built in ROS, controlling a robot in a Unity HRI simulator. It is found using these metrics that modalities employing tracking (where the robot imitates the operator’s movements) are generally superior, but that allowing neck control may hinder the performance of other simultaneous modalities such as navigation. Emotion control was achieved with the available equipment but was found to potentially benefit from a hypothetical bespoke input device for the task

  • 336. Cranefield, Stephen
    et al.
    Dignum, Frank
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Incorporating Social Practices in BDI Agent Systems2019Ingår i: AAMAS '19: International Conference on Autonomous Agents and Multiagent Systems AAMAS 2019, ASSOC COMPUTING MACHINERY , 2019, s. 1901-1903Konferensbidrag (Refereegranskat)
  • 337.
    Croon, Anna
    et al.
    Umeå universitet, Samhällsvetenskaplig fakultet, Informatik.
    Palmquist, Lena
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Institutionen för datavetenskap.
    Virtualisering och den sociala konstruktionen av kön och teknik2001Ingår i: Från Siffror till Surfning: könsperspektiv på informationsteknik / [ed] Kallin, Lena & Palmquist, Lena, Lund: Studentlitteratur , 2001, s. 71-91Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 338.
    Da Alesandro, Rafael
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Investigation of anomalies in a RTC system using Machine Learning2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In a Real Time Clearing System (RTCS) there are several thousands of transactions per second, and even more messages are sent back and forth. Th‘e high volume of messages and transactions being sent within the system eventually leads to some anomalies arising. Th‘is thesis examines how to detect such anomalies with unsupervised Machine Learning models such as, Support Vector Machine(SVM) One Class (OC), Isolation Forest (iForest) and Local Outlier Factor(LOF). Th‘e main objective is to investigate if anomaly detection is useable in Cinnobers RTCS, only using unsupervised models and if they perform at an acceptable level. Th‘e evaluation of the models will be done using a rough labeling method to score them on detection rate, F-score and Ma‹hews correlation coecient (MCC). Th‘e results of the thesis shows that SVM OC is the best model of the three, but requires hyper parameter tuning to perform at an acceptab lelevel so that it may be used for the RTCS without human supervision.

  • 339.
    Dackland, Krister
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Elmroth, Erik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Design and performance modeling of parallel block matrix factorizations for distributed memory multicomputers1992Ingår i: Proceedings of the Industrial Mathematics Week, 1992, s. 102-116Konferensbidrag (Refereegranskat)
    Abstract [en]

    Efficient and scalable parallel block algorithms for the LU factorization with partial pivoting, the Cholesky, and QR factorizations in a distributed memory multicomputer environment are presented. The distributed system is viewed as a ring of processors and the algorithms correspond to shared memory algorithms parallelized on block level (explicit parallelism). Performance of the algorithms are analyzed theoretically and illustrated empirically by implementations on the Intel iPSC/2 hypercube. A model predicting performance and optimal block size is presented.

  • 340.
    Dackland, Krister
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Elmroth, Erik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Parallel block matrix factorizations for distributed memory multicomputers1992Rapport (Övrigt vetenskapligt)
  • 341.
    Dackland, Krister
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Elmroth, Erik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Ring-oriented block matrix factorization algorithms for shared and distributed memory architectures1992Rapport (Övrigt vetenskapligt)
  • 342.
    Dackland, Krister
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Elmroth, Erik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Kågström, Bo
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Högpresterande beräkningscentrum norr (HPC2N).
    A ring-oriented approach for block matrix factorizations on shared and distributed memory architectures1993Ingår i: Proceedings of the Sixth SIAM Conference on Parallel Processing for Scientific Computing / [ed] R. F. Sincovec et al., Norfolk: SIAM Publications , 1993, s. 330-338Konferensbidrag (Refereegranskat)
    Abstract [en]

    A block (column) wrap-mapping approach for design of parallel block matrix factorization algorithms that are (trans)portable over and between shared memory multiprocessors (SMM) and distributed memory multicomputers (DMM) is presented. By reorganizing the matrix on the SMM architecture, the same ring-oriented algorithms can be used on both SMM and DMM systems with all machine dependencies comprised to a small set of communication routines. The algorithms are described on high level with focus on portability and scalability aspects. Implementation aspects of the LU , Cholesky, and QR factorizations and machine specific communication routines for some SMM and DMM systems are discussed. Timing results show that our portable algorithms have similar performance as machine specific implementations. 1 Introduction With the introduction of advanced parallel computer architectures a demand for efficient and portable algorithms has emerged. Several attempts to design algorithms and implementat.

  • 343.
    Dackland, Krister
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Elmroth, Erik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Kågström, Bo
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Högpresterande beräkningscentrum norr (HPC2N).
    Van Loan, C.
    Parallel block matrix factorizations on the shared memory multiprocessor IBM 3090 VF/600J1992Ingår i: International Journal of Supercomputer Applications, ISSN 0890-2720, Vol. 6, nr 1, s. 69-97Artikel i tidskrift (Refereegranskat)
  • 344.
    Dackland, Krister
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Elmroth, Erik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Kågström, Bo
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Högpresterande beräkningscentrum norr (HPC2N).
    Van Loan, Charles
    Design and evaluation of parallel block algorithms:  LU factorization on an IBM 3090 VF/600J1992Ingår i: Proceedings of the Fifth SIAM Conference on Parallel Processing for Scientific Computing / [ed] Jack Dongarra, Ken Kennedy, Paul Messina, Danny C. Sorensen, Robert G. Voigt, Houston: SIAM Publications , 1992, s. 3-10Konferensbidrag (Refereegranskat)
  • 345.
    Dackland, Krister
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Institutionen för datavetenskap. Umeå universitet, Teknisk-naturvetenskaplig fakultet, HPC2N (Högpresterande beräkningscentrum norr).
    Kågström, Bo
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Institutionen för datavetenskap. Umeå universitet, Teknisk-naturvetenskaplig fakultet, HPC2N (Högpresterande beräkningscentrum norr).
    Blocked Algorithms and Software for Reduction of a Regular Matrix Pair to Generalized Schur Form1999Ingår i: ACM Transactions on Mathematical Software, Vol. 25, nr 4, s. 425-454Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A two-stage blocked algorithm for reduction of a regular matrix pair (A, B) to upper Hessenberg-triangular form is presented. In stage 1 (A, B) is reduced to block upper Hessenberg-triangular form using mainly level 3 (matrix-matrix) operations that permit data reuse in the higher levels of a memory hierarchy. In the second stage all but one of the r subdiagonals of the block Hessenberg A-part are set to zero using Givens rotations. The algorithm proceeds in a sequence of supersweeps, each reducing m columns. The updates with respect to row and column rotations are organized to reference consecutive columns of A and B. To further improve the data locality, all rotations produced in a supersweep are stored to enable a left-looking reference pattern, i.e., all updates are delayed until they are required for the continuation of the supersweep. Moreover, we present a blocked variant of the single diagonal double-shift QZ method for computing the generalized Schur form of(A, B) in upper Hessenberg-triangular form. The blocking for improved data locality is done similarly, now by restructuring the reference pattern of the updates associated with the bulge chasing in the QZ iteration. Timing results show that our new blocked variants outperform the current LAPACK routines, including drivers for the generalized eigenvalue problem, by a factor 2-5 for sufficiently large problems.

  • 346.
    Dahlberg, Emanuel
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Electricity in a 2D mechanicssimulator for education2011Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Electricity can be a difficult topic to grasp since it is abstract, it is e.g. not possible to see the current and the voltage in a circuit. If electricity can be simulated and visualized, it can become less abstract and easier to understand. This thesis covers the process of simulating electricity in real-time together with a mechanics simulator, called Algodoo.

    The process of analyzing electric circuits from a computers point of view is covered as well as different ways of simulating electric motors, generators and lasers. A large part of the thesis covers how to integrate the electricity and the mechanics simulators in a stable and accurate way. Furthermore, making the objects of the mechanics simulator able to conduct electricity is also covered.

    The thesis shows that it is possible to simulate electricity in real-time, and that physically correct conducting objects requires a lot of processing power, but can be simplified without losing too much correctness. The thesis also shows that the electrical and mechanics simulators preferably should be solved together to get a stable simulation.

    Simulating electricity opens up an endless number of interactive scenarios, e.g. mechanical

    switches, potentiometers, relays and even logic gates. It can be a helpful aid as an

    introduction to electronics and since the simulators are integrated, it can also provide an

    introduction to mechanical work. The amount of energy required to perform dierent tasks

    can be compared and analyzed.

  • 347.
    Dahlberg, Marina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Rasterization of Fragmented Spatial Data2014Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The Geographical Information Systems (GIS) is nowadays a large industry that has evolved from a highly specialized niche to a technology that affects nearly every aspect of our lives. There is a big challenge to use the functionality of GIS within the organization that works with data in the ordinary old-fashioned way using files stored locally in the computer. The availability of sharing and visualizing data forces an organization to invest in modern software solutions. Sweco is one of the organizations which offer the software solution SMIL to complement the information stored in the organization with spatial support.

    The aim of the work presented in this thesis was to measure the time needed for rasterization of an image map with different amount of features in a simplified prototype of SMIL with similar data flow organization. This prototype was developed in consultation with Sweco’s software architect and GIS consultant and was tested using the organization’s network capacity.

    Four different types of tests, which were implemented in order to investigate the presence of possible tipping points, illustrated the similar result that when the number of requested features passes one thousand, both the time needed for rasterization and the size of the raster image increases rapidly. The fifth test, that was implemented in order to analyze the time the involved modules in the system needed to generate a response, identified GeoServer as an apparent critical module in the system that delays data flow when the number of requested features passes one thousand and it can slow down the system when the number of requested features passes ten thousand.

  • 348.
    Dahlberg, Timoteus
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Compact Representation and Efficient Manipulation of Sparse Multidimensional Arrays2014Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Efficient manipulation of sparse multidimensional arrays, or tensors, is of interest because their decompositions have applications in many different areas. These areas include neuroscience, machine learning, psychometrics, data mining, numerical analysis, and more. This thesis aims to develop the performance-critical parts of a library for manipulating sparse multidimensional arrays by focusing on sorting them in one or more dimensions—a fundamental operation on which many other operations can be built.

    High performance is achieved by tailoring algorithms to a compact representation scheme. Evaluation is done on different algorithms and implementation techniques. The result is shown to be 20 to 70 times faster than qsort in the C standard library. The resulting library is open source.

  • 349.
    Dahlgren Lindström, Adam
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Structured Prediction using Voted Conditional Random FieldsLink Prediction in Knowledge Bases2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Knowledge bases are useful in the validation of automatically extracted information, and for hypothesis selection during the extraction process. Building knowledge bases is a dfficult task and the process is bound to miss facts. Therefore, the existence of facts can be estimated using link prediction, i.e., by solving the structured prediction problem.It has been shown that combining directly observable features with latent features increases performance. Observable features include, e.g., the presence of another chain of facts leading to the same end point. Latent features include, e.g, properties that are not modelled by facts on the form subject-predicate-object, such as being a good actor. Observable graph features are modelled using the Path Ranking Algorithm, and latent features using the bilinear RESCAL model. Voted Conditional Random Fields can be used to combine feature families while taking into account their complexity to minimize the risk of training a poor predictor. We propose a combined model fusing these theories together with a complexity analysis of the feature families used. In addition, two simple feature families are constructed to model neighborhood properties.The model we propose captures useful features for link prediction, but needs further evaluation to guarantee effcient learning. Finally, suggestions for experiments and other feature families are given.

  • 350.
    Danielsson, Karin
    et al.
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för informatik.
    Lindgren, Helena
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Mulvenna, Maurice
    Computer Science, Ulster University.
    Nilsson, Ingeborg
    Umeå universitet, Medicinska fakulteten, Institutionen för samhällsmedicin och rehabilitering, Arbetsterapi.
    Waterworth, John
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för informatik.
    Digital technology in healthcare and elderly care2017Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The focus of this ECCE 2017 panel is on digital technology in healthcare and elderly care. The discussion concerns the design of technology and the use of technology for health. 

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