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  • 301.
    Chatzidaki, Maria D.
    et al.
    Örebro University, School of Science and Technology. Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece.
    Papadimitriou, Konstantinos
    Agricultural University of Athens.
    Alexandraki, Voula
    Agricultural University of Athens.
    Tsirvouli, Eirini
    Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece.
    Chakim, Zena
    Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece.
    Ghazal, Aghiad
    University of Copenhagen, Denmark.
    Mortensen, Kell
    University of Copenhagen, Denmark.
    Yaghmur, Anan
    University of Copenhagen, Denmark.
    Salentinig, Stefan
    Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland.
    Papadimitriou, Vassiliki
    Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece.
    Tsakalidou, Effie
    Agricultural University of Athens.
    Xenakis, Aristotelis
    Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece; Örebro University, Sweden .
    Microemulsions as potential carriers of nisin: effect of composition on the structure and efficacyManuscript (preprint) (Other academic)
  • 302.
    Chen, Zetao
    et al.
    The ARC Australian Centre of Excellence for Robotic Vision, Queensland University of Technology, Brisbane, Australia .
    Lowry, Stephanie
    Örebro University, School of Science and Technology.
    Jacobson, Adam
    The ARC Australian Centre of Excellence for Robotic Vision, Queensland University of Technology, Brisbane, Australia .
    Ge, ZongYuan
    The ARC Australian Centre of Excellence for Robotic Vision, Queensland University of Technology, Brisbane, Australia .
    Milford, Michael
    The ARC Australian Centre of Excellence for Robotic Vision, Queensland University of Technology, Brisbane, Australia .
    Distance metric learning for feature-agnostic place recognition2015In: Proceedings of the 2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 2015, 2556-2563 p.Conference paper (Refereed)
    Abstract [en]

    The recent focus on performing visual navigation and place recognition in changing environments has resulted in a large number of heterogeneous techniques each utilizing their own learnt or hand crafted visual features. This paper presents a generally applicable method for learning the appropriate distance metric by which to compare feature responses from any of these techniques in order to perform place recognition under changing environmental conditions. We implement an approach which learns to cluster images captured at spatially proximal locations under different conditions, separated from frames captured at different places. The formulation is a convex optimization, guaranteeing the existence of a global solution. We evaluate the general applicability of our method on two benchmark change datasets using three typical image pre-processing and feature types: GIST, Principal Component Analysis and learnt Convolutional Neural Network features. The results demonstrate that the distance metric learning approach uniformly improves single-image-based visual place recognition performance across all feature types. Furthermore, we demonstrate that this performance improvement is maintained when the sequence-based algorithm SeqSLAM is applied to the single-image place recognition results, leading to state-of-the-art performance.

  • 303.
    Cheng, Xiaoliang
    et al.
    Department of Mathematics, Zhejiang University, Hangzhou, Zhejiang, China.
    Lin, Guangliang
    Department of Mathematics, Zhejiang University, Hangzhou, Zhejiang, China.
    Zhang, Ye
    Örebro University, School of Science and Technology. Department of Mathematics.
    Gong, Rongfang
    Department of Mathematics, Nanjing University of Aeronautics and Astronautics, Nanjing, China.
    Gulliksson, Mårten
    Örebro University, School of Science and Technology. Department of Mathematics.
    A modified coupled complex boundary method for an inverse chromatography problem2017In: Journal of Inverse and Ill-Posed Problems, ISSN 0928-0219, E-ISSN 1569-3945Article in journal (Refereed)
    Abstract [en]

    Adsorption isotherms are the most important parameters in rigorous models of chromatographic processes. In this paper, in order to recover adsorption isotherms, we consider a coupled complex boundary method (CCBM), which was previously proposed for solving an inverse source problem [2]. With CCBM, the original boundary fitting problem is transferred to a domain fitting problem. Thus, this method has advantages regarding robustness and computation in reconstruction. In contrast to the traditional CCBM, for the sake of the reduction of computational complexity and computational cost, the recovered adsorption isotherm only corresponds to the real part of the solution of a forward complex initial boundary value problem. Furthermore, we take into account the position of the profiles and apply the momentum criterion to improve the optimization progress. Using Tikhonov regularization, the well-posedness, convergence properties and regularization parameter selection methods are studied. Based on an adjoint technique, we derive the exact Jacobian of the objective function and give an algorithm to reconstruct the adsorption isotherm. Finally, numerical simulations are given to show the feasibility and efficiency of the proposed regularization method.

  • 304.
    Chennaya, Veronica
    Örebro University, School of Science and Technology.
    Correlation between Environmental Pollutants and Neuropsychological Disorders2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Environmental pollutants are all around us. How are they affecting human brains? My hypothesis is that there is a correlation between these widespread chemicals and neuropsychological disorders. I have read and written about four disorders; autism spectrum disorder, attention deficit hyperactivity disorder, schizophrenia and bipolar disorder which I have tried to correlate to environmental pollutants; metals, endocrine disrupting chemicals, pesticides and air pollutants through literature (through searching Google Scholar and PubMed). Most research found supports my hypothesis of a correlation between pollutants and neuropsychological disorders both in epidemiological studies as well as studies conducted on humans. Additionally there are animal studies that show correlation between different chemicals found in nature and traits or symptoms characteristic for a certain disorder. The findings show correlation but also raise other questions such as; what role do additional aspects play, such as social and demographic influences? What is the reason of the skewed gender bias towards the male sex in autism spectrum disorder and attention deficit hyperactivity disorder? 

  • 305.
    Christensson, Johan
    et al.
    Örebro University, School of Science and Technology.
    Gustafsson, Ludwig
    Örebro University, School of Science and Technology.
    Utveckling av geometrisk reverse engineering med 3D-skanningsutrustning2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    3D scanning technology has had enormous growth in the last 10 years.[1] The 3D scanning solutions on the market today can create digital copies of a physical shape in minutes, with a precision of about 40 µm [1]. This makes the 3D scanner an effective and tolerance-proof solution for applications including; Quality insurance, Aftermarket parts, Aesthetic limb manufacturing and Reverse engineering.

    Reverse engineering is a mechanical construction method where the engineer uses a, so called, "Top-down" methodology. The method consists of getting basic understanding about an unknown product by disassembling it.

    Geometric reverse engineering, on the other hand, shares the basic values of reverse engineering, but instead of getting a better understanding of the components in a product, the objective is to create usable CAD-files from a physical object.

    In the case of geometric reverse engineering and 3D scanning equipment at Volvos model construction department, it is very important to create a fully functional model of the object, where all measures and parameters that might need changing (for casting optimization), can be changed in an easy fashion. It is also important for the model to have a high tolerance level and low surface roughness.

    This thesis main focus is to develop a time efficient method of working with 3D scanners and geometric reverse engineering for Volvo GTO.

  • 306.
    Cicek, Mehmet
    Örebro University, School of Science and Technology.
    Universell Hjuladapter2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis has been carried out in collaboration with JOSAM in Örebro, which is a leading company in the trend and wheel alignment on commercial vehicles. The company was founded in 1972 and has manufactured equipment for 40 years.

     

    The thesis is about the wheel adapter problems to be fixed to aluminum rims.

     

    The result was a solution proposed for a wheel adapter, which works the same for aluminum and steel wheels. It has the flexibility to meet the 15-inch up to 24-inch rims.

  • 307.
    Cirillo, Marcello
    Örebro University, School of Science and Technology.
    Planning in inhabited environments: human-aware task planning and activity recognition2011In: Künstliche Intelligenz, ISSN 0933-1875, E-ISSN 1610-1987, Vol. 25, no 4, 355-358 p.Article in journal (Refereed)
    Abstract [en]

    Our work addresses issues related to the cohabitation of service robots and people in unstructured environments. We propose new planning techniques to empower robot means-end reasoning with the capability of taking into account human intentions and preferences. We also address the problem of human activity recognition in instrumented environments. We employ a constraint-based approach to realize a continuous inference process to attach a meaning to sensor traces as detected by sensors distributed in the environment.

  • 308.
    Cirillo, Marcello
    et al.
    Örebro University, School of Science and Technology.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Human-aware planning for robots embedded in ambient ecologies2012In: Pervasive and Mobile Computing, ISSN 1574-1192, E-ISSN 1873-1589, Vol. 8, no 4, 542-561 p.Article in journal (Refereed)
    Abstract [en]

    We address the issue of human-robot cohabitation in smart environments. In particular, the presence of humans in a robot's work space has a profound influence on how the latter should plan its actions. We propose the use of Human-Aware Planning, an approach in which the robot exploits the capabilities of a sensor-rich environment to obtain information about the (current and future) activities of the people in the environment, and plans its tasks accordingly.

    Here, we formally describe the planning problem behind our approach, we analyze its complexity and we detail the algorithm of our planner. We then show two application scenarios that could benefit from the techniques described. The first scenario illustrates the applicability of human-aware planning in a domestic setting, while the second one illustrates its use for a robotic helper in a hospital. Finally, we present a five hour-long test run in a smart home equipped with real sensors, where a cleaning robot has been deployed and where a human subject is acting. This test run in a real setting is meant to demonstrate the feasibility of our approach to human-robot interaction.

  • 309.
    Cirillo, Marcello
    et al.
    Örebro University, School of Science and Technology.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Uras, Tansel
    Department of Computer Science, University of Southern California, USA.
    Koenig, Sven
    Department of Computer Science, University of Southern California, USA.
    Integrated Motion Planning and Coordination for Industrial Vehicles2014In: Proceedings of the 24th International Conference on Automated Planning and Scheduling, 2014Conference paper (Refereed)
    Abstract [en]

    A growing interest in the industrial sector for autonomous ground vehicles has prompted significant investment in fleet management systems. Such systems need to accommodate on-line externally imposed temporal and spatial requirements, and to adhere to them even in the presence of contingencies. Moreover, a fleet management system should ensure correctness, i.e., refuse to commit to requirements that cannot be satisfied. We present an approach to obtain sets of alternative execution patterns (called trajectory envelopes) which provide these guarantees. The approach relies on a constraint-based representation shared among multiple solvers, each of which progressively refines trajectory envelopes following a least commitment principle.

  • 310.
    Cirillo, Marcello
    et al.
    Örebro University, School of Science and Technology.
    Uras, Tansel
    Department of Computer Science, University of Southern California, USA.
    Koenig, Sven
    Department of Computer Science, University of Southern California, USA.
    A lattice-based approach to multi-robot motion planning for non-holonomic vehicles2014In: Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems, 2014, 232-239 p.Conference paper (Refereed)
    Abstract [en]

    Coordinating fleets of autonomous, non-holonomic vehicles is paramount to many industrial applications. While there exists solutions to efficiently calculate trajectories for individual vehicles, an effective methodology to coordinate their motions and to avoid deadlocks is still missing. Decoupled approaches, where motions are calculated independently for each vehicle and then centrally coordinated for execution, have the means to identify deadlocks, but not to solve all of them. We present a novel approach that overcomes this limitation and that can be used to complement the deficiencies of decoupled solutions with centralized coordination. Here, we formally define an extension of the framework of lattice-based motion planning to multi-robot systems and we validate it experimentally. Our approach can jointly plan for multiple vehicles and it generates kinematically feasible and deadlock-free motions.

  • 311.
    Claesson, Anna
    Örebro University, School of Science and Technology.
    Fytoremediering av jordbruksmark med annuell solros (Helianthus annuus peredovic)2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Inledning: Metaller är ämnen som förkommer naturligt i vår miljö men kan också spridas via t. ex. industrier. Många metaller kan vara skadliga för djur och natur. Metallföroreningar ökar idag i vår omgivning samt i åkermarken. Den ökande halten metaller i jordbruksmark ställer till problem då grödor ackumulerar de hälsofarliga ämnena i sin biomassa vilket riskerar konsumentens hälsa. Exponeringen av metaller har visat sig vara kopplade till flera sjukdomar. Det finns flera olika metoder för sanering av metallförorenade områden, en miljövänlig saneringsmetod är fytoremediering. Att fytoremediera mark innebär sanering, återställning eller stabilisering av ett område med hjälp av vegetation. Ett exempel på en beprövad gröda som visat en effektiv metallackumulation är Helianthus annuus (solros). Syfte: Att mäta och analysera metallinnehåll i åkermark samt undersöka den annuella solrosen Helianthus annuus peredovic förmåga att ackumulera metaller från mark. Metod och material: Odlingsförsök av H. annuus p. i jord från åkermark samt metallanalys på jord innan sådd och efter skörd. Plantor skördades vid två tillfällen för metallanalys. Resultat: H. annuus p. visade effektiv ackumulation av 16 metaller i grönmassa. Slutsats: H.annuus p. är en effektiv ackumulerade av många metaller och således en möjlig gröda att använda vid fytoremediering av åkermark.

  • 312.
    Claesson, Daniel
    et al.
    Örebro University, School of Science and Technology.
    Sjöstrand, Jonas
    Örebro University, School of Science and Technology.
    Automatisering av svetsprocessen på valstråd2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    FNsteel in Linköping manufactures wire rod, a product used by the prefabricated industry for the manufacture of prestressed concrete elements eg. hollow cores, beams, beam joints and railroad slides. In manufacturing, a wire is drawn through a wire drawing machine that reduces the wires cross sectional area and increase the length while the wire is given a different metal structure. The drawn wire is then turned to three or seven-wire wire rod. In manufacturing, operators weld together wire threads and the handling of the wire is today manual. In the future, the company wants to automate its welding process by splicing of wire threads as there is a heavy and one-sided work for operators, and also in order to increase productivity. The thesis work is a product development project that contains an analysis of the manufacturing process today and suggestions for standardization to automate, as well as design documentation for automation of certain elements of the process.

    During the course of the process, it has been identified that the process is not mature for automation without the company first having to come up with a standard for the process to enable automation of the entire welding process. A number of elements in the process require continued work to enable automation of the process, while it is already possible to automate certain parts of the process as these can easily be standardized. The conceptual solution developed consists of pneumatic cylinders, engineered wire clips and hydraulic wire cutters.

  • 313.
    Clefjord Ljungberg, Hanna
    et al.
    Örebro University, School of Science and Technology.
    Brunzell, Malin
    Örebro University, School of Science and Technology.
    Analys av inköpsbeteende av underleverantörer2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 314. Clemmensen, K. E.
    et al.
    Bahr, A.
    Ovaskainen, O.
    Dahlberg, A.
    Ekblad, Alf
    Örebro University, School of Science and Technology.
    Wallander, H.
    Stenlid, J.
    Finlay, R. D.
    Wardle, D. A.
    Lindahl, B. D.
    Roots and associated fungi drive long-term carbon sequestration in boreal forest2013In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 339, no 6127, 1615-1618 p.Article in journal (Refereed)
    Abstract [en]

    Boreal forest soils function as a terrestrial net sink in the global carbon cycle. The prevailing dogma has focused on aboveground plant litter as a principal source of soil organic matter. Using C-14 bomb-carbon modeling, we show that 50 to 70% of stored carbon in a chronosequence of boreal forested islands derives from roots and root-associated microorganisms. Fungal biomarkers indicate impaired degradation and preservation of fungal residues in late successional forests. Furthermore, 454 pyrosequencing of molecular barcodes, in conjunction with stable isotope analyses, highlights root-associated fungi as important regulators of ecosystem carbon dynamics. Our results suggest an alternative mechanism for the accumulation of organic matter in boreal forests during succession in the long-term absence of disturbance.

  • 315.
    Comont, David
    et al.
    Aberystwyth University.
    Albert, Andreas
    Helmholtz Zentrum München.
    Aphalo, Pedro
    Helsingfors universitet.
    Gabersick, Alenka
    University of Ljubljana.
    Hauser, Marie Teres
    University of Natural Resources and Life Sciences - Vienna.
    Jansen, Marcel
    University College of Cork.
    Robson, Matthew
    Helsingfors universitet.
    Schreiner, Monika
    Leibniz-Institute of Vegetable and Ornamental Plants - Großbeeren, Germany.
    Strid, Åke
    Örebro University, School of Science and Technology.
    Gwynn-Jones, Dylan
    Aberystwyth University.
    Exploring latitudinal variation in UV radiation and climate: impacts on a model grass system2011In: Abstracts of the 1st Annual Meeting of COST Action FA0906 UV4growth, Szeged: Biological Research Center of the Hungarian Academy of Sciences , 2011, 14-14 p.Conference paper (Refereed)
    Abstract [en]

    Perennial ryegrass (Lolium perenne) seedlings were grown at 14 European locations across a latitudinal gradient spanning 37 to 68°N. Seedlings planted in nutrient enriched vermiculite were grown outdoors over five weeks between the 29th June and the 3rd August 2010. At each location there were three treatments – open, filtered with cellulose acetate (UV transparent) and filtered with Mylar (UV opaque). Plants were regularly watered and outdoor climatic conditions were monitored at nearby meteorological stations. The aim of the experiment was to assess the significance of ambient UV radiation to L.perenne, both at each location and across the gradient in terms of aboveground biomass, tiller number, and the level of UV protective plant pigments. Material was further screened using metabolite fingerprinting (FT-IR spectroscopy) to assess local, regional and latitudinal variation in total plant chemistry. Data presented will explore and interpret the complex variations in growth and chemistry looking at local responses and the latitudinal gradient explored.

  • 316.
    Comont, David
    et al.
    Aberystwyth University.
    Martinez Abaigar, Javier
    University of La Rioja.
    Albert, Andreas
    Helmholtz Zentrum München.
    Aphalo, Pedro
    Helsingfors universitet.
    Causton, David R
    Aberystwyth University.
    López Figueroa, Félix
    University of Málaga.
    Gaberscik, Alenka
    University of Ljubljana.
    Llorens, Laura
    University of Girona.
    Hauser, Marie-Theres
    University of Natural Resulrces and Life Sciences-BOKU, Wien.
    Jansen, Marcel A K
    University College Cork.
    Kardefelt, Majlis
    Abisko forskningsstation.
    de la Coba Luque, Paqui
    University of Málaga.
    Neubert, Susanne
    University of Natural Resulrces and Life Sciences-BOKU, Wien.
    Núnez-Olivera, Encarnación
    University of La Rioja.
    Olsen, Jorunn
    Norwegian University of Life Sciences.
    Robson, Matthew
    Helsingfors universitet.
    Schreiner, Monika
    Leibniz-Institute of Vegetable and Ornamental Crops - Großbeeren.
    Sommaruga, Ruben
    University of Innsbruck.
    Strid, Åke
    Örebro University, School of Science and Technology.
    Torre, Sissel
    Norwegian University of Life Sciences.
    Turunen, Minna
    University of Lapland.
    Veljovic-Jovanovic, Sonja
    Institute for Multidisciplinary Research - Belgrade.
    Verdaguer, Dolors
    University of Girona.
    Vidovic, Marija
    Institute for Multidisciplinary Research - Belgrade.
    Wagner, Johanna
    University of Innsbruck.
    Winkler, Jana Barbro
    Helmholtz Zentrum München.
    Zipoli, Gaetano
    C.N.R. Ibimet - Firenze.
    Gwynn-Jones, Dylan
    University of Aberystwyth.
    UV responses of Lolium perenne raised along a latitudinal gradient across Europe: a filtration study2012In: Physiologia Plantarum: An International Journal for Plant Biology, ISSN 0031-9317, E-ISSN 1399-3054, Vol. 145, 604-618 p.Article in journal (Refereed)
    Abstract [en]

    Lolium perenne (cv. AberDart) was grown at 14 locations along a latitudinal gradient across Europe (37–68◦N) to study the impact of ultraviolet radiation (UV) and climate on aboveground growth and foliar UV-B absorbing compounds. At each location, plants were grown outdoors for 5 weeks in a replicated UV-B filtration experiment consisting of open, UV-B transparent (cellulose diacetate) and UV-B opaque (polyester) environments. Fourier transform-infrared spectroscopy was used to compare plantmetabolite profiles in relation to treatment and location. UV radiation and climatic parameters were determined for each location from online sources and the data were assessed using a combination of ANOVA and multiple regression analyses. Most of the variation in growth between the locations was attributable to the combination of climatic parameters, with minimum temperature identified as an important growth constraint. However, no single environmental parameter could consistently account for the variability in plant growth. Concentrations of foliar UV-B absorbing compounds showed a positive trend with solar UV across the latitudinal gradient; however, this relationship was not consistent in all treatments. The most striking experimental outcome from this study was the effect of presence or absence of filtration frames onUV-absorbing compounds. Overall, the study demonstrates the value of an European approach in studying the impacts of natural UV across a large latitudinal gradient. We have shown the feasibility of coordinated UV filtration at multiple sites but have also highlighted the need for open controls and careful interpretation of plant responses.

  • 317.
    Conti, Mauro
    et al.
    Department of Mathematics, University of Padua, Padua, Italy.
    Dragoni, Nicola
    Örebro University, School of Science and Technology. DTU Compute, Technical University of Denmark (DTU), Kgs. Lyngby, Denmark.
    Lesyk, Viktor
    DTU Compute, Technical University of Denmark (DTU), Kgs. Lyngby, Denmark; Centre for Applied Autonomous Sensor Systems (AASS), Örebro University, Örebro, Sweden.
    A Survey of Man In The Middle Attacks2016In: IEEE Communications Surveys and Tutorials, ISSN 1553-877X, E-ISSN 1553-877X, Vol. 18, no 3, 2027-2051 p.Article in journal (Refereed)
    Abstract [en]

    The Man-In-The-Middle (MITM) attack is one of the most well known attacks in computer security, representing one of the biggest concerns for security professionals. MITM targets the actual data that flows between endpoints, and the confidentiality and integrity of the data itself. In this paper, we extensively review the literature on MITM to analyse and categorize the scope of MITM attacks, considering both a reference model, such as the open systems interconnection (OSI) model, as well as two specific widely used network technologies, i.e., GSM and UMTS. In particular, we classify MITM attacks based on several parameters, like location of an attacker in the network, nature of a communication channel, and impersonation techniques. Based on an impersonation techniques classification, we then provide execution steps for each MITM class. We survey existing countermeasures and discuss the comparison among them. Finally, based on our analysis, we propose a categorisation of MITM prevention mechanisms, and we identify some possible directions for future research.

  • 318.
    Coradeschi, Silvia
    et al.
    Örebro University, School of Science and Technology.
    Cesta, Amadeo
    CNR, Italy.
    Cortellessa, Gabriella
    CNR, Italy.
    Coraci, Luca
    CNR, Italy.
    Gonzalez, Javier
    Malaga University.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Furfari, Francesco
    CNR, Italy.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Orlandini, Andrea
    CNR, Italy.
    Palumbo, Filippo
    CNR, Italy.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    von Rump, Stephan
    Giraff AB.
    Ullberg, Jonas
    Örebro University, School of Science and Technology.
    Östlund, Britt
    Lund University, Lund, Sweden.
    GiraffPlus: combining social interaction and long term monitoring for promoting independent living2013In: 2013 6TH INTERNATIONAL CONFERENCE ON HUMAN SYSTEM INTERACTIONS (HSI), New York, 2013, 578-585 p.Conference paper (Refereed)
    Abstract [en]

    Early detection and adaptive support to changing individual needs related to ageing is an important challenge in today’s society. In this paper we present a system called GiraffPlus that aims at addressing such a challenge and is developed in an on-going European project. The system consists of a network of home sensors that can be automatically configured to collect data for a range of monitoring services; a semi-autonomous telepresence robot; a sophisticated context recognition system that can give high-level and long term interpretations of the collected data and respond to certain events; and personalized services delivered through adaptive user interfaces for primary users. The system performs a range of services including data collection and analysis of long term trends in behaviors and physiological parameters (e.g. relating to sleep or daily activity); warnings, alarms and reminders; and social interaction through the telepresence robot. The latter is based on the Giraff telepresence robot, which is already in place in a number of homes. Particular emphasis is put on user evaluation outside the laboratories. A distinctive aspect of the project is that the GiraffPlus system will be installed and evaluated in at least 15 homes of elderly people. The concept of “useworthiness” is central in order to assure that the GiraffPlus system provides services that are easy to use and worth using. In addition, by using existing and affordable components we strive to achieve a system that is affordable and close to commercialization.

  • 319.
    Coradeschi, Silvia
    et al.
    Örebro University, School of Science and Technology.
    Cortellessa, GabriellaKristoffersson, AnnicaÖrebro University, School of Science and Technology.Loutfi, AmyÖrebro University, School of Science and Technology.
    Proceedings of the Ro-man 2012 Workshop on Social Robotics Telepresence2012Conference proceedings (editor) (Other academic)
  • 320.
    Coradeschi, Silvia
    et al.
    School of Science and Technology, Örebro University, Örebro, Sweden.
    Cortellessa, GabriellaCNR - National Research Council of Italy, Istituto di Scienze e Tecnologie della Cognizione, Rome, Italy.Kristoffersson, AnnicaÖrebro University, School of Science and Technology.Loutfi, AmyÖrebro University, School of Science and Technology.Severinson Eklundh, KerstinCI Group, CSC, KTH Royal Institute of Technology, Stockholm, Sweden.
    Proceedings of the 2011 HRI Workshop on Social Robotic Telepresence2011Conference proceedings (editor) (Other academic)
  • 321.
    Coradeschi, Silvia
    et al.
    Örebro University, School of Science and Technology.
    Kristoffersson, Annica
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Von Rump, Stephen
    Cesta, Amedeo
    Cortellessa, Gabriella
    Gonzalez, Javier
    Towards a methodology for longitudinal evaluation of social robotic telepresence for elderly2011In: 1st Workshop on Social Robotic Telepresence at HRI 2011, 2011Conference paper (Refereed)
    Abstract [en]

    This paper describes a methodology for performing longitudinal evaluations when a social robotic telepresence system is deployed in realistic environments. This work is the core of an Ambient Assisted Living Project called ExCITE, Enabling Social Interaction Through Telepresence. The ExCITE project is geared towards an elderly audience and has as aim to increase social interaction among elderly, their family and healthcare services by using robotic telepresence. The robotic system used in the project is called the Giraff robot and over a three year period, prototypes of this platform are deployed at a number of test-sites in different European countries where user feedback is collected and fedback into the refinement of the prototype. In this paper, we discuss the methodology of ExCITE in particular relation to other methodologies for longitudinal evaluation. The paper also provides a discussion of the possible pitfalls and risks in performing longitudinal studies of this nature particularly as they relate to social robotic telepresence technologies.

  • 322.
    Coradeschi, Silvia
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Wrede, Britta
    Bielefeld University.
    A short review of symbol grounding in robotic and intelligent systems2013In: Künstliche Intelligenz, ISSN 0933-1875, E-ISSN 1610-1987, Vol. 27, no 2, 129-136 p.Article in journal (Refereed)
    Abstract [en]

    This paper gives an overview of the research papers published in Symbol Grounding in the period from the beginning of the 21st century up 2012. The focus is in the use of symbol grounding for robotics and intelligent system. The review covers a number of subtopics, that include, physical symbol grounding, social symbol grounding, symbol grounding for vision systems, anchoring in robotic systems, and learning symbol grounding in software systems and robotics. This review is published in conjunction with a special issue on Symbol Grounding in the Künstliche Intelligenz Journal.

  • 323.
    Czégény, Gyula
    et al.
    Institute of Biology, University of Pécs, Pécs, Hungary; Institute of Plant Biology, Biological Research Centre, Szeged, Hungary.
    Wu, Min
    Department of Chemistry and Molecular Biology, University of Gothenburg, Göteborg, Sweden.
    Dér, András
    Institute of Biophysics, Biological Research Centre, Szeged, Hungary.
    Eriksson, Leif A
    Department of Chemistry and Molecular Biology, University of Gothenburg, Göteborg, Sweden.
    Strid, Åke
    Örebro University, School of Science and Technology.
    Hideg, Éva
    Institute of Biology, University of Pécs, Pécs, Hungary.
    Hydrogen peroxide contributes to the ultraviolet-B (280-315 nm) induced oxidative stress of plant leaves through multiple pathways2014In: FEBS Letters, ISSN 0014-5793, E-ISSN 1873-3468, Vol. 588, no 14, 2255-2261 p.Article in journal (Refereed)
    Abstract [en]

    Solar UV-B (280-315 nm) radiation is a developmental signal in plants but may also cause oxidative stress when combined with other environmental factors. Using computer modelling and in solution experiments we show that UV-B is capable of photosensitizing hydroxyl radical production from hydrogen peroxide. We present evidence that the oxidative effect of UV-B in leaves is at least two-fold: (i) it increases cellular hydrogen peroxide concentrations, to a larger extent in pyridoxine antioxidant mutant pdx1.3-1 Arabidopsis and (ii) is capable of a partial photo-conversion of both ‘natural’ and ‘extra’ hydrogen peroxide to hydroxyl radicals. As stress conditions other than UV can increase cellular hydrogen peroxide levels, synergistic deleterious effects of various stresses may be expected already under ambient solar UV-B.

  • 324.
    d. C. Silva-Lopez, Lia Susana
    et al.
    Örebro University, School of Science and Technology.
    Broxvall, Mathias
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Towards configuration planning with partially ordered preferences: representation and results2015In: Künstliche Intelligenz, ISSN 0933-1875, E-ISSN 1610-1987, Vol. 9, no 2, 173-183 p.Article in journal (Refereed)
    Abstract [en]

    Configuration planning for a distributed robotic system is the problem of how to configure the system over time in order to achieve some causal and/or information goals. A configuration plan specifies what components (sensor, actuator and computational devices), should be active at different times and how they should exchange information. However, not all plans that solve a given problem need to be equally good, and for that purpose it may be important to take preferences into account. In this paper we present an algorithm for configuration planning that incorporates general partially ordered preferences. The planner supports multiple preference categories, and hence it solves a multiple-objective optimization problem: for a given problem, it finds all possible valid, non-dominated configuration plans. The planner has been able to successfully cope with partial ordering relations between quantitative preferences in practically acceptable times, as shown in the empirical results. Preferences here are represented as c-semirings, and are used for establishing dominance of a solution over another in order to obtain a set of configuration plans that will constitute the solution of a configuration planning problem with partially ordered preferences. The dominance operators tested in this paper are Pareto and Lorenz dominance. Our solver considers one guiding heuristic for obtaining the first solution, and then switches to a dominance based monotonically decreasing heuristic used for pruning dominated partial configuration plans. In our empirical results, we perform a statistical study in the space of problem instances and establish families of problems for which our approach is computationally feasible.

  • 325.
    Dal, Alexander
    et al.
    Örebro University, School of Science and Technology.
    Norrbacka, Johannes
    Örebro University, School of Science and Technology.
    Utläggningsrapportering i en mobil webbapplikation2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes the implementation of expense reporting in a mobile web application. Two different types of expenses could be reported: remuneration and time deviations. In addition to the creation of new expenses, existing expenses should be able to be edited or deleted. The implementation would be designed in such a way that it prevents the user from making data entry errors in an intuitive way. 

     

    The bachelor’s thesis was performed for Flex Datasystem AB in their mobile web application, Flex WebApp. Due to delimitations made during the project only functionality for the expense-type remuneration was implemented.

  • 326.
    Dandan, Kinan
    et al.
    Örebro University, School of Science and Technology.
    Albitar, Houssam
    Örebro University, School of Science and Technology.
    Ananiev, Anani
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    School of Science and Technology, Örebro University, Örebro Sweden.
    Confined Spaces: Cleaning Techniques and Robot-based Surface Cleaning2016In: American Scientific Research Journal for Engineering, Technology and Science, ISSN 2313-4402, Vol. 22, no 1, 210-230 p.Article in journal (Refereed)
    Abstract [en]

    The requirements of the working and safety norms demonstrate significant need of increased efficiency and improved working conditions in cleaning confined spaces. This paper presents an overview of the existing technologies and solutions for cleaning large confined spaces. A special attention is directed for cleaning interior surface of confined spaces used mainly for storing bulk materials or liquids, such as silos. The cleaning technologies for confined space depend on several aspects as the build-up material, the surface material, the ambient conditions. Four cleaning techniques are presented in this paper. The mechanisms and robots related to the studied problem are surveyed and evaluated from the viewpoint of their capability to clean interior surfaces. The dominating majority of the existing cleaning equipment is constructed to serve cleaning the entire volume of the respective confined space (silo), but not for cleaning the interior surface.

  • 327.
    Dandan, Kinan
    et al.
    Örebro University, School of Science and Technology.
    Albitar, Houssam
    Örebro University, School of Science and Technology.
    Ananiev, Anani
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Motion Control of Siro: The Silo Cleaning Robot2015In: International Journal of Advanced Robotic Systems, ISSN 1729-8806, E-ISSN 1729-8814, Vol. 12, 184Article in journal (Refereed)
    Abstract [en]

    Both the principle of operation and the motion-control system of a suspended robot for surface cleaning in silos are presented in this paper. The mechanical design is a reasonable compromise between basically contradictory factors in the design: the small entrance and the large surface of the confined space, and the suspension and the stabilization of the robot. The design consists of three main parts: a support unit, the cleaning robot and a cleaning mechanism. The latter two parts enter the silo in a folded form and, thereafter, the robot’s arms are spread in order to achieve stability during the cleaning process. The vertical movement of the robot is achieved via sequential crawling motions.

    The control system is divided into two separate subsystems, the robot’s control subsystem and a support-unit control subsystem, in order to facilitate different operational modes. The robot has three principle motion-control tasks: positioning the robot inside the silo, holding a vertical position during the cleaning process and a crawling movement.

    A scaled prototype of the robot has been implemented and tested to prove the concept, in order to make certain that the mechanical design suits the main functions of the robotic system, to realize the robot’s design in an industrial version and to test it in a realistic environment.

  • 328.
    Dandan, Kinan
    et al.
    Örebro University, School of Science and Technology.
    Ananiev, Anani
    Örebro University, School of Science and Technology.
    Ivan, Kalaykov
    Örebro University, School of Science and Technology.
    SIRO: the silos surface cleaning robot concept2013Conference paper (Refereed)
    Abstract [en]

    A concept of a suspended robot for surface cleaning in silos is presented in this paper. The main requirements and limitations resulting from the specific operational conditions are discussed. Due to the large dimension of the silo as a confined space, specific kinematics of the robot manipulator is proposed. The major problems in its design are highlighted and an approach to resolve them is proposed. The suggested concept is a reasonable compromise between the basic contradicting factors in the design: small entrance and large surface of the confined space, suspension and stabilization of the robot

  • 329.
    Dandan, Kinan
    et al.
    Örebro University, School of Science and Technology.
    Ananiev, Anani
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    School of Science and Technology, Örebro University, Örebro, Sweden.
    Dynamical Analysis of Silo Surface Cleaning Robot using Finite Element Method2016In: International Journal of Mechanical Engineering & Technology (IJMET), ISSN 0976-6340, Vol. 07, no 01, 190-202 p., IJMET_07_01_020Article in journal (Refereed)
    Abstract [en]

    All mechanical systems are subjected to dynamic forces when they are in functioning. Thus a dynamical analysis has to be studied to determine the system behaviour. The vibration is of interest to study, due to its destructive or constructive effect. In the present era computational techniques are quite common and are very reliable as far as the modal analysis is concerned. In this work, the robot of silo cleaning is analysed for its vibration behaviour using finite element method (FEM).The robot was modelled and meshed in ANSYS. Modal analysis was conducted to calculate few initial natural frequencies. After carrying out the modal analysis, harmonic and transient analysis were done to see the response of the robot under dynamic loading. It was observed that robot is safe in its entire range of operation.

  • 330.
    Dandan, Kinan
    et al.
    Örebro University, School of Science and Technology.
    Ananiev, Anani
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Modeling and simulation of a silo cleaning robot2014In: Mobile Service Robotics / [ed] Krazystof Kotowski, Mohammad O Tokhi and Gurvinder S Virk, Singapore: World Scientific, 2014, 627-635 p.Conference paper (Refereed)
    Abstract [en]

    A suspended robot for surface cleaning in silos is presented in this paper. Thesuggested concept is a reasonable compromise between the basic contradictingfactors in the design: small entrance and large surface of the confined space,suspension and stabilization of the robot. A dynamic study for the suspendedrobot is presented in this paper. A dynamic simulation in MSC ADAMS iscarried out to confirm the results from the theoretic study.

  • 331.
    Daniel, Alberto
    Örebro University, School of Science and Technology.
    An Introduction to Invariant Theory2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This work is an attempt to explain in some detail section III D of the paper:

    N.J.A. Sloane. "Error-correcting codes and Invariant Theory:

    New application of a Nineteenth-Century Technique". For that, we will be concerned with polynomial invariants of  finite groups which come from a group action. We will introduce the basic notions of Invariant Theory to give an almost self-contained proof of Molien's theorem, and also present applications on linear codes.

  • 332.
    Danielsson, Linda
    et al.
    Örebro University, School of Science and Technology.
    Sternefors, Karin
    Örebro University, School of Science and Technology.
    Vad i undervisning genom problemlösning i grupp har forskning visat påverkar elevers matematiska förmågor?2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Problem solving within mathematics teaching has been more highlighted during the last decades. In the Swedish curriculum for primary school problem solving has got a bigger role, being one of five mathematical competencies that students should be given the chance to develop during school. In the Swedish curriculum there is also a focus on communication and how students should get the opportunity to engage in conversations and to reason about mathematics. This can be brought out by letting the students work together with their classmates in different kinds of group constellations. Problem solving in groups can be designed in different ways and affects the development of students’ mathematical competencies. In this systematic literature study three general themes were discovered, on how problem solving in groups can support students in developing their mathematical competencies; how problem solving can be designed, under a longer or shorter period of time, access to supporting structures and tools and the group constellation’s affect.

  • 333.
    Daoutis, Marios
    Örebro University, School of Science and Technology.
    Knowledge based perceptual anchoring: grounding percepts to concepts in cognitive robots2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    A successful articial cognitive agent needs to integrate its perception of the environment with reasoning and actuation. A key aspect of this integration is the perceptual-symbolic correspondence, which intends to give meaning to the concepts the agent refers to { known as Anchoring. However, perceptual representations alone (e.g., feature lists) cannot entirely provide sucient abstraction and enough richness to deal with the complex nature of the concepts' meanings. On the other hand, neither plain symbol manipulation appears capable of attributing the desired intrinsic meaning.

    We approach this integration in the context of cognitive robots which operate in the physical world. Specically we investigate the challenge of establishing the connection between percepts and concepts referring to objects, their relations and properties.We examine how knowledge representation can be used together with an anchoring framework, so as to complement the meaning of percepts while supporting linguistic interaction. This implies that robots need to represent both their perceptual and semantic knowledge, which is often expressed in dierent abstraction levels and may originate from dierent modalities.

    The solution proposed in this thesis concerns the specication, design and implementation ofa hybrid cognitive computational model, which extends a classical anchoring framework, in order to address the creation and maintenance of the perceptual-symbolic correspondences. The model is based on four main aspects: (a) robust perception, by relying on state-of-the art techniques from computer vision and mobile robot localisation; (b) symbol grounding, using topdown and bottom-up information acquisition processes as well as multi-modal representations; (c) knowledge representation and reasoning techniques in order to establish a common language and semantics regarding physical objects, their properties and relations, that are to be used between heterogeneous robotic agents and humans; and (d) commonsense information in order to enable high-level reasoning as well as to enhance the semantic

    descriptions of objects.

    The resulting system and the proposed integration has the potential to strengthen and expand the knowledge of a cognitive robot. Specically, by providing more robust percepts it is possible to cope better with the ambiguity and uncertainty of the perceptual data. In addition, the framework is able to exploit mutual interaction between dierent levels of representation while integrating dierent sources of information. By modelling and using semantic & perceptual knowledge, the robot can: acquire, exchange and reason formally about concepts, while prior knowledge can become a cognitive bias in the acquisition of novel concepts.

    List of papers
    1. Using Knowledge Representation for Perceptual Anchoring in a Robotic System
    Open this publication in new window or tab >>Using Knowledge Representation for Perceptual Anchoring in a Robotic System
    2008 (English)In: International Journal on Artificial Intelligence Tools, ISSN 0218-2130, Vol. 17, no 5, 925-944 p.Article in journal (Refereed) Published
    Abstract [en]

    In this work we introduce symbolic knowledge representation and reasoning capabilities to enrich perceptual anchoring. The idea that encompasses perceptual anchoring is the creation and maintenance of a connection between the symbolic and perceptual description that refer to the same object in the environment. In this work we further extend the symbolic layer by combining a knowledge representation and reasoning (KRR) system with the anchoring module to exploit a knowledge inference mechanisms. We implemented a prototype of this novel approach to explore through initial experimentation the advantages of integrating a symbolic knowledge system to the anchoring framework in the context of an intelligent home. Our results show that using the KRR we are better able to cope with ambiguities in the anchoring module through exploitation of human robot interaction.

    National Category
    Engineering and Technology Computer and Information Science
    Research subject
    Computer and Systems Science
    Identifiers
    urn:nbn:se:oru:diva-5175 (URN)
    Available from: 2009-02-24 Created: 2009-01-29 Last updated: 2017-10-18Bibliographically approved
    2. Grounding commonsense knowledge in intelligent systems
    Open this publication in new window or tab >>Grounding commonsense knowledge in intelligent systems
    2009 (English)In: Journal of Ambient Intelligence and Smart Environments, ISSN 1876-1364, E-ISSN 1876-1372, Vol. 1, no 4, 311-321 p.Article in journal (Refereed) Published
    Abstract [en]

    Ambient environments which integrate a number of sensing devices and actuators intended for use by human users need to be able to express knowledge about objects, their functions and their properties to assist in the performance of everyday tasks. For this to occur perceptual data must be grounded to symbolic information that in its turn can be used in the communication with the human. For symbolic information to be meaningful it should be part of a rich knowledge base that includes an ontology of concepts and common sense. In this work we present an integration between ResearchCyc and an anchoring framework that mediates the connection between the perceptual information in an intelligent home environment and the reasoning system. Through simple dialogues we validate how objects placed in the home environment are grounded by a network of sensors and made available to a larger KB where reasoning is exploited. This first integration work is a step towards integrating the richness of a KRR system developed over many years in isolation, with a physically embedded intelligent system.

    Place, publisher, year, edition, pages
    Amsterdam: IOS Press, 2009
    Keyword
    Physical Symbol Grounding, Commonsense Knowledge Representation, Human Robot Interaction, Intelligent Home
    National Category
    Computer Science
    Research subject
    Computer Science; Information technology
    Identifiers
    urn:nbn:se:oru:diva-8485 (URN)10.3233/AIS-2009-0040 (DOI)000207842000002 ()2-s2.0-78651496919 (Scopus ID)
    Available from: 2009-11-09 Created: 2009-11-09 Last updated: 2017-12-12Bibliographically approved
    3. Cooperative knowledge based perceptual anchoring
    Open this publication in new window or tab >>Cooperative knowledge based perceptual anchoring
    2012 (English)In: International journal on artificial intelligence tools, ISSN 0218-2130, Vol. 21, no 3, 1250012Article in journal (Refereed) Published
    Abstract [en]

    In settings where heterogenous robotic systems interact with humans, information from the environment must be systematically captured, organized and maintained in time. In this work, we propose a model for connecting perceptual information to semantic information in a multi-agent setting. In particular, we present semantic cooperative perceptual anchoring, that captures collectively acquired perceptual information and connects it to semantically expressed commonsense knowledge. We describe how we implemented the proposed model in a smart environment, using different modern perceptual and knowledge representation techniques. We present the results of the systemand investigate different scenarios in which we use the common sense together with perceptual knowledge, for communication, reasoning and exchange of information.

    Place, publisher, year, edition, pages
    World Scientific, 2012
    Keyword
    Cognitive robotics; physical symbol grounding; commonsense information; multi-agent perception; object recognition
    National Category
    Computer Science
    Research subject
    Computer and Systems Science
    Identifiers
    urn:nbn:se:oru:diva-24226 (URN)10.1142/S0218213012500121 (DOI)000305795900008 ()2-s2.0-84863086324 (Scopus ID)
    Funder
    Swedish Research Council
    Available from: 2012-08-06 Created: 2012-08-05 Last updated: 2017-12-07Bibliographically approved
    4. Towards concept anchoring for cognitive robots
    Open this publication in new window or tab >>Towards concept anchoring for cognitive robots
    2012 (English)In: Intelligent Service Robotics, ISSN 1861-2784, Vol. 5, no 4, 213-228 p.Article in journal (Refereed) Published
    Abstract [en]

    We present a model for anchoring categorical conceptual information which originates from physical perception and the web. The model is an extension of the anchoring framework which is used to create and maintain over time semantically grounded sensor information. Using the augmented anchoring framework that employs complex symbolic knowledge from a commonsense knowledge base, we attempt to ground and integrate symbolic and perceptual data that are available on the web. We introduce conceptual anchors which are representations of general, concrete conceptual terms. We show in an example scenario how conceptual anchors can be coherently integrated with perceptual anchors and commonsense information for the acquisition of novel concepts.

    Place, publisher, year, edition, pages
    Springer Berlin/Heidelberg, 2012
    Keyword
    Anchoring; Categorical perception; Near sets; Knowledge representation; Commonsense information
    National Category
    Robotics Computer Vision and Robotics (Autonomous Systems) Computer Science
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-26831 (URN)10.1007/s11370-012-0117-z (DOI)000208947900002 ()2-s2.0-84867580722 (Scopus ID)
    Funder
    Swedish Research Council
    Available from: 2013-01-10 Created: 2013-01-10 Last updated: 2017-10-18Bibliographically approved
  • 334.
    Daoutis, Marios
    Örebro University, School of Science and Technology.
    Knowledge based perceptual anchoring: grounding percepts to concepts in cognitive robots2013In: Künstliche Intelligenz, ISSN 0933-1875, E-ISSN 1610-1987, 1-4 p.Article in journal (Refereed)
    Abstract [en]

    Perceptual anchoring is the process of creating and maintaining a connection between the sensor data corresponding to a physical object and its symbolic description. It is a subset of the symbol grounding problem, introduced by Harnad (Phys. D, Nonlinear Phenom. 42(1–3):335–346, 1990) and investigated over the past years in several disciplines including robotics. This PhD dissertation focuses on a method for grounding sensor data of physical objects to the corresponding semantic descriptions, in the context of cognitive robots where the challenge is to establish the connection between percepts and concepts referring to objects, their relations and properties. We examine how knowledge representation can be used together with an anchoring framework, so as to complement the meaning of percepts while supporting better linguistic interaction with the use of the corresponding concepts. The proposed method addresses the need to represent and process both perceptual and semantic knowledge, often expressed in different abstraction levels, while originating from different modalities. We then focus on the integration of anchoring with a large scale knowledge base system and with perceptual routines. This integration is applied in a number of studies, where in the context of a smart home, several evaluations spanning from spatial and commonsense reasoning to linguistic interaction and concept acquisition.

  • 335.
    Daoutis, Marios
    et al.
    Örebro University, School of Science and Technology.
    Coradeschi, Silvia
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Cooperative knowledge based perceptual anchoring2012In: International journal on artificial intelligence tools, ISSN 0218-2130, Vol. 21, no 3, 1250012Article in journal (Refereed)
    Abstract [en]

    In settings where heterogenous robotic systems interact with humans, information from the environment must be systematically captured, organized and maintained in time. In this work, we propose a model for connecting perceptual information to semantic information in a multi-agent setting. In particular, we present semantic cooperative perceptual anchoring, that captures collectively acquired perceptual information and connects it to semantically expressed commonsense knowledge. We describe how we implemented the proposed model in a smart environment, using different modern perceptual and knowledge representation techniques. We present the results of the systemand investigate different scenarios in which we use the common sense together with perceptual knowledge, for communication, reasoning and exchange of information.

  • 336.
    Daoutis, Marios
    et al.
    Örebro University, School of Science and Technology.
    Coradeschi, Silvia
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Knowledge representation for anchoring symbolic concepts to perceptual data2012In: Bridges between the Methodological and Practical Work of the Robotics and Cognitive Systems Communities - From Sensors to Concepts / [ed] Springet Publishing, Springer Publishing Company, 2012Chapter in book (Refereed)
  • 337.
    Daoutis, Marios
    et al.
    Örebro University, School of Science and Technology.
    Coradeschi, Silvia
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Towards concept anchoring for cognitive robots2012In: Intelligent Service Robotics, ISSN 1861-2784, Vol. 5, no 4, 213-228 p.Article in journal (Refereed)
    Abstract [en]

    We present a model for anchoring categorical conceptual information which originates from physical perception and the web. The model is an extension of the anchoring framework which is used to create and maintain over time semantically grounded sensor information. Using the augmented anchoring framework that employs complex symbolic knowledge from a commonsense knowledge base, we attempt to ground and integrate symbolic and perceptual data that are available on the web. We introduce conceptual anchors which are representations of general, concrete conceptual terms. We show in an example scenario how conceptual anchors can be coherently integrated with perceptual anchors and commonsense information for the acquisition of novel concepts.

  • 338.
    Daoutis, Marios
    et al.
    Örebro University, School of Science and Technology.
    Mavridis, Nikolaos
    Towards a Model for Grounding Semantic Composition2014Conference paper (Refereed)
  • 339.
    Dashti, HesamAddin T.
    et al.
    School of Math and Computer Science, University of Tehran.
    Aghaeepour, NimaSchool of Math and Computer Science, University of Tehran.Asadi, SaharÖrebro University, School of Science and Technology.Bastani, MeysamSchool of Math and Computer Science, University of Tehran.Delafkar, ZahraSchool of Math and Computer Science, University of Tehran.Disfani, Fatemeh M.School of Math and Computer Science, University of Tehran.Ghaderi, Serveh M.School of Math and Computer Science, University of Tehran.Kamali, ShahinSchool of Math and Computer Science, University of Tehran.Pashami, SepidehÖrebro University, School of Science and Technology.Siahpirani, Alireza F.School of Math and Computer Science, University of Tehran.
    Dynamic Positioning based on Voronoi Cells (DPVC)2006Collection (editor) (Refereed)
    Abstract [en]

    In this paper we are proposing an approach for flexible positioning of players in Soccer Simulation in a Multi-Agent environment. We introduce Dynamic Positioning based on Voronoi Cells (DPVC) as a new method for players' positioning which uses Voronoi Diagram for distributing agents in the field. This method also uses Attraction Vectors that indicate agents' tendency to specific objects in the field with regard to the game situation and players' roles. Finally DPVC is compared with SBSP as the conventional method of positioning.

  • 340.
    Dashto, Ramin
    et al.
    Örebro University, School of Science and Technology.
    Abduljabar, Foras
    Örebro University, School of Science and Technology.
    Automatisera handsvetsning samt reducering av oxidering vid svetsning2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study of welding process for stainless steel sinks made at Intra Mölntorp AB. The company is a market leader in the production of sinks and sanitary equipment in stainless steel. The aim is to carry out a feasibility study to automate the corner welding of sinks with special dimensions and to reduce oxidation at the corner welding.

    Hand welding is used today for large sinks that does not fit in the robot cell where the company welds their standard sinks, as the larger benches require more space than is available in current robotic cell. There is not time in the robot cell to weld also the approximately 5 000 special sinks produced each year.

    By developing a manual hand welding to automated welding company can reduce the production time for each sink while increasing work safety. Two proposals have been prepared for how a new cell benches with special dimensions can look.

    Finally, a new model of the gas nozzle was developed. The cover serves to protect the weld area from oxygen penetrating into and discolour the surfaces being heated up. The new cap provides better protection against oxygen than the previous cap was used, and it is made of a heat-resistant material while it can be easily manufactured in more copies. There remains some work to investigate the causes of discoloration, since both temperature, cooling time and shielding gas concentration affect discoloration.The discoloration can not be eliminated only with the cover design.

    The company Mölntorp AB has two possible solution concept that can facilitate the production to decide and to work further with the gas nozzle where the causes of discoloration closer needs to be investigated.

  • 341.
    Davidsson, Jonas
    Örebro University, School of Science and Technology.
    Bestämning av bruttotemperaturexpansionskoefficient för Faradol 8102013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor thesis was carried out at ABB Power Products/Instrument Transformers in Ludvika. The purpose of the work has been to examine the thermal expansion for an isolating oil that is used in the product Capacitor Voltage Transformer (CVT). The oil’s own expansion coefficient                          was already known, but the purpose of the work was to determine a gross thermal expansion coefficient, with other words to examine the amount of influense the other componets had on the volume expansion inside the unit.

    To decide the gross thermal expansion coefficient a test has been carried out in a climat chamer. To performe the test two aluminum tanks, each with a measurement tube mounted on the top were used. One of the tanks was filled with oil and the other one was filled with oil and capacitor contents corresponding tio the contents in a CVT. The two test objects were then exposed to temperatures reaching from -60°C to 65°C in steps of 10°C. During this time a number of volume measurements were performed on the two test objects. These measure­ments together with a few correction parameters were used to decide the thermal expansion coefficient for both the oil (only for control purpose) and the capacitor contents. Together these two gives the gross thermal expansion coefficient for all posible volume combinations.

    The results from the tests has been analised and visualised in the form of tables an diagrams. After that the thermal expansion coefficient for the oil and the capacitorcontents, for different temperatures was calculated. Bult on those calculations the avarege thermal expansion coeff­icient for the temperatureintervals was calculated, and finaly an modle for calculating the gross thermal expansion coefficient was created. At the end conclusions were drawn from the results. 

  • 342.
    Dawes, Melissa A.
    et al.
    Mountain Ecosystems, WSL Institute for Snow and Avalanche Research-SLF, Davos Dorf, Switzerland .
    Hagedorn, Frank
    Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), , Birmensdorf, Switzerland .
    Handa, Ira Tanya
    Université du Québec à Montréal (UQÀM), Montreal, Canada .
    Streit, Kathrin
    Paul Scherrer Institute, Villigen, Switzerland .
    Ekblad, Alf
    Örebro University, School of Science and Technology.
    Rixen, Christian
    Mountain Ecosystems, WSL Institute for Snow and Avalanche Research-SLF, Davos Dorf, Switzerland .
    Körner, Christian
    University of Basel, Basel, Switzerland .
    Hättenschwiler, Stephan
    Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Montpellier, France.
    An alpine treeline in a carbon dioxide-rich world: synthesis of a nine-year free-air carbon dioxide enrichment study2013In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 171, no 3, 623-637 p.Article in journal (Refereed)
    Abstract [en]

    We evaluated the impacts of elevated CO2 in a treeline ecosystem in the Swiss Alps in a 9-year free-air CO2 enrichment (FACE) study. We present new data and synthesize plant and soil results from the entire experimental period. Light-saturated photosynthesis (A max) of ca. 35-year-old Larix decidua and Pinus uncinata was stimulated by elevated CO2 throughout the experiment. Slight down-regulation of photosynthesis in Pinus was consistent with starch accumulation in needle tissue. Above-ground growth responses differed between tree species, with a 33 % mean annual stimulation in Larix but no response in Pinus. Species-specific CO2 responses also occurred for abundant dwarf shrub species in the understorey, where Vaccinium myrtillus showed a sustained shoot growth enhancement (+11 %) that was not apparent for Vaccinium gaultherioides or Empetrum hermaphroditum. Below ground, CO2 enrichment did not stimulate fine root or mycorrhizal mycelium growth, but increased CO2 effluxes from the soil (+24 %) indicated that enhanced C assimilation was partially offset by greater respiratory losses. The dissolved organic C (DOC) concentration in soil solutions was consistently higher under elevated CO2 (+14 %), suggesting accelerated soil organic matter turnover. CO2 enrichment hardly affected the C–N balance in plants and soil, with unaltered soil total or mineral N concentrations and little impact on plant leaf N concentration or the stable N isotope ratio. Sustained differences in plant species growth responses suggest future shifts in species composition with atmospheric change. Consistently increased C fixation, soil respiration and DOC production over 9 years of CO2 enrichment provide clear evidence for accelerated C cycling with no apparent consequences on the N cycle in this treeline ecosystem.

  • 343.
    De Donno, Michele
    et al.
    DTU Compute, Technical University of Denmark, Kongens Lyngby, Denmark.
    Dragoni, Nicola
    Örebro University, School of Science and Technology. DTU Compute, Technical University of Denmark, Kongens Lyngby, Denmark.
    Giaretta, Alberto
    Örebro University, School of Science and Technology.
    Spognardi, Angelo
    DTU Compute, Technical University of Denmark, Kongens Lyngby, Denmark.
    Analysis of DDoS-Capable IoT Malwares2017In: Proceedings of the 2017 Federated Conference on Computer Science and Information Systems / [ed] M. Ganzha, L. Maciaszek, M. Paprzycki, 2017, 807-816 p.Conference paper (Refereed)
    Abstract [en]

    The Internet of Things (IoT) revolution promises to make our lives easier by providing cheap and always connected smart embedded devices, which can interact on the Internet and create added values for human needs. But all that glitters is not gold. Indeed, the other side of the coin is that, from a security perspective, this IoT revolution represents a potential disaster. This plethora of IoT devices that flooded the market were very badly protected, thus an easy prey for several families of malwares that can enslave and incorporate them in very large botnets. This, eventually, brought back to the top Distributed Denial of Service (DDoS) attacks, making them more powerful and easier to achieve than ever. This paper aims at provide an up-to-date picture of DDoS attacks in the specific subject of the IoT, studying how these attacks work and considering the most common families in the IoT context, in terms of their nature and evolution through the years. It also explores the additional offensive capabilities that this arsenal of IoT malwares has available, to mine the security of Internet users and systems. We think that this up-to-date picture will be a valuable reference to the scientific community in order to take a first crucial step to tackle this urgent security issue.

  • 344.
    De Donno, Michele
    et al.
    DTU Compute, Technical University of Denmark, Kongens Lyngby, Denmark.
    Giaretta, Alberto
    Örebro University, School of Science and Technology.
    Dragoni, Nicola
    Örebro University, School of Science and Technology.
    Spognardi, Angelo
    DTU Compute, Technical University of Denmark, Kongens Lyngby, Denmark; Dipartimento Informatica, Sapienza Università di Roma, Italy.
    A Taxonomy of Distributed Denial of Service Attacks2017In: i-Society 2017: Proceedings / [ed] Charles A. Shoniregun, Galyna A. Akmayeva, Infonomics Society, 2017, 99-106 p.Conference paper (Refereed)
  • 345.
    Deckmyn, G.
    et al.
    Univ Antwerp, Antwerp, Belgium.
    Meyer, A.
    Univ Gothenburg, Dept Biol & Environm Sci, Gothenburg, Sweden.
    Smits, M. M.
    Hasselt Univ, Ctr Environm Sci, Diepenbeek, Belgium.
    Ekblad, Alf
    Örebro University, School of Science and Technology.
    Grebenc, T.
    Slovenian Forestry Inst, Ljubljana, Slovenia.
    Komarov, A.
    Russian Acad Sci, Inst Physicochem & Biol Problems Soil Sci, Pushchino, Moscow Region, Russia.
    Kraigher, H.
    Slovenian Forestry Inst, Ljubljana, Slovenia.
    Simulating ectomycorrhizal fungi and their role in carbon and nitrogen cycling in forest ecosystems2014In: Canadian Journal of Forest Research, ISSN 0045-5067, E-ISSN 1208-6037, Vol. 44, no 6, 535-553 p.Article, review/survey (Refereed)
    Abstract [en]

    Although ectomycorrhizal fungi play an important role in forest ecosystem functioning, they are usually not included in forest growth or ecosystem models. Simulation is hampered by two main issues: a lack of understanding of the ecological functioning of the ectomycorrhizal fungi and a lack of adequate basic data for parameterization and validation. Concerning these issues, much progress has been made during the past few years, but this information has not found its way into the forest and soil models. In this paper, state-of-the-art insight into ectomycorrhizal functioning and basic values are described in a manner transparent to nonspecialists and modelers, together with the existing models and model strategies. As such, this paper can be the starting point and the motivator to include ectomycorrhizal fungi into existing soil and forest ecosystem models.

  • 346.
    DELAHAYE, QUENTIN
    Örebro University, School of Science and Technology.
    Framework for Classical Conditioning in a MobileRobot: Development of Pavlovian Model andDevelopment of Reinforcement Learning Algorithmto Avoid and Predict Noxious Events2014Student paper other, 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nowadays, robots have more and more sensors and the technologies allow

    using them with less contraints as before. Sensors are important to learn about

    the environment. But the sensors can be used for classical conditioning, and

    create behavior for the robot. One of the behavior developed in this thesis is

    avoiding and predicting obstacles.

    The goal of this thesis is to propose a model which consists of developing a

    specific behavior to avoid noxious event, obstacles.

  • 347.
    Demirel, Isak
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Kinnunen, Annica
    Örebro University, School of Science and Technology.
    Önnberg, Anna
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Laboratory Medicine, Clinical Microbiology, Örebro University Hospital, Örebro, Sweden.
    Söderquist, Bo
    Örebro University, School of Medicine, Örebro University, Sweden. Örebro University Hospital. Department of Laboratory Medicine, Clinical Microbiology.
    Persson, Katarina
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Comparison of host response mechanisms evoked by extended spectrum beta lactamase (ESBL)- and non-ESBL-producing uropathogenic E. coli2013In: BMC Microbiology, ISSN 1471-2180, E-ISSN 1471-2180, Vol. 13, 181Article in journal (Refereed)
    Abstract [en]

    Background: Infections caused by extended spectrum beta-lactamases (ESBL)-producing bacteria have been emerging worldwide and the majority of ESBL-producing E. coli strains are isolated from patients with urinary tracts infections. The purpose of this study was to compare the host-response mechanisms in human polymorphonucleated leukocytes (PMN) and renal epithelial cells when stimulated by ESBL-or non-ESBL-producing uropathogenic E. coli (UPEC) isolates. The host-pathogen interaction of these ESBL-producing strains in the urinary tract is not well studied.

    Results: The ability of ESBL strains to evoke ROS-production from PMN cells was significantly higher than that of the non-ESBL strains. The growth of ESBL strains was slightly suppressed in the presence of PMN compared to non-ESBL strains after 30 min and 2 h, but the opposite was observed after 5 and 6 h. The number of migrating PMN was significantly higher in response to ESBL strains compared to non-ESBL strains. Stimulation of A498 cells with ESBL strains elicited lower production of IL-6 and IL-8 compared to non-ESBL strains.

    Conclusion: Significant differences in host-response mechanisms were identified when host cells were stimulated by ESBL-or non-ESBL producing strains. The obtained results on the early interactions of ESBL-producing strains with the host immune system may provide valuable information for management of these infections.

  • 348.
    Dessne, Karin
    Örebro University, School of Science and Technology.
    Supporting knowledge management with information technology: the significance of formal and informal structures2012Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Knowledge Management (KM) is a relatively young field of research. It has traditionally aimed at managing work in organisations often by the assistance of supporting Information Technology (IT).

    In this thesis, the definition of KM is expressed as facilitating the intertwined process of learning and knowing in an organisation. in order to support this process by IT KM needs to be based on an understanding of the significance of the formal and informal structures that organisations are built on. Using the word knowing rather than knowledge assists in approaching the issue of how to facilitate learning and knowing, since it declares knowing as a process or as a state of mind. This process feeds on what is available in the form of nourishment, which is supplied in the form of information. KM then has two ways of supporting learning and knowing: by nourishing and by encouraging this process.

    Two analysis frameworks were constructed from two subsequent literature reviews of KM, Computer Supported Collaborative Work/Lerarning (CSCW/CSCL), and Communities of Practice (CoP). These models were used to describe and analyse the learning process of the selected case, a Swedish military organisation. It soon became evident that the formal learning process did not work as intended, and that the informal structures and processes struggled to accomplish the results that the formal process failed to deliver. The formal and informal processes were not aligned and neither worked satisfyingly. Informal structures exists within formal structures and they are both equally important. They are intertwined and dependent on each other. as the findings of this case study has revealed.

    In supporting learning and knowing in organisations, IT needs to support both formal and informal structures. IT could nourish structures and processes, and IT could encourage participation and interaction in them. As learning is based on interaction supporting it is vital, but at the same time, no interaction will occur without nourishment. These are the impĺications for IT when designing for learning and knowing in organisations. It is not only a matter of supplying and making information available, but also of encouraging interaction in aligned formal and informal structures.

  • 349.
    Di Lello, Enrico
    et al.
    Katholieke Univ Leuven, Div PMA, Dept Mech Engn, Heverlee, Belgium.
    Trincavelli, Marco
    Örebro University, School of Science and Technology. Centre for Applied Autonomous Sensor Systems, Örebro University, Örebro, Sweden;.
    Bruyninckx, Herman
    Katholieke Univ Leuven, Div PMA, Dept Mech Engn, Heverlee, Belgium; Eindhoven Univ Technol, Sect CST, Dept Mech Engn, Eindhoven, Netherlands .
    De laet, Tinne
    Katholieke Univ Leuven, Fac Engn Sci, Heverlee, Belgium.
    Augmented Switching Linear Dynamical System Model for Gas Concentration Estimation with MOX Sensors in an Open Sampling System2014In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 14, no 7, 12533-12559 p.Article in journal (Refereed)
    Abstract [en]

    In this paper, we introduce a Bayesian time series model approach for gas concentration estimation using Metal Oxide (MOX) sensors in Open Sampling System (OSS). Our approach focuses on the compensation of the slow response of MOX sensors, while concurrently solving the problem of estimating the gas concentration in OSS. The proposed Augmented Switching Linear System model allows to include all the sources of uncertainty arising at each step of the problem in a single coherent probabilistic formulation. In particular, the problem of detecting on-line the current sensor dynamical regime and estimating the underlying gas concentration under environmental disturbances and noisy measurements is formulated and solved as a statistical inference problem. Our model improves, with respect to the state of the art, where system modeling approaches have been already introduced, but only provided an indirect relative measures proportional to the gas concentration and the problem of modeling uncertainty was ignored. Our approach is validated experimentally and the performances in terms of speed of and quality of the gas concentration estimation are compared with the ones obtained using a photo-ionization detector.

  • 350.
    Di Mauro, Alessio
    et al.
    DTU Compute, Technical University of Denmark, Denmark.
    Dragoni, Nicola
    Örebro University, School of Science and Technology. DTU Compute, Technical University of Denmark, Denmark.
    Adaptive Multipath Key Reinforcement for Energy Harvesting Wireless Sensor Networks2015In: Procedia Computer Science, ISSN 1877-0509, E-ISSN 1877-0509, Vol. 63, 48-55 p.Article in journal (Refereed)
    Abstract [en]

    Energy Harvesting - Wireless Sensor Networks (EH-WSNs) constitute systems of networked sensing nodes that are capable of extracting energy from the environment and that use the harvested energy to operate in a sustainable state. Sustainability, seen as design goal, has a significant impact on the design of the security protocols for such networks, as the nodes have to adapt and optimize their behaviour accordingto the available energy. Traditional key management schemes do not take energy into account, making them not suitable for EH-WSNs. In this paper we propose a new multipath key reinforcement scheme specifically designed for EH-WSNs. The proposed scheme allows each node to take into consideration and adapt to the amount of energy available in the system.In particular, we present two approaches, one static and one fully dynamic, and we discuss some experimental results.

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