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  • 351.
    Loutfi, Amy
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Coradeschi, Silvia
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lilienthal, Achim J.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Gonzalez, Javier
    Dept. of System Engineering and Automation, University of Malaga.
    Gas Distribution Mapping of Multiple Odour Sources using a Mobile Robot2009Inngår i: Robotica (Cambridge. Print), ISSN 0263-5747, E-ISSN 1469-8668, Vol. 27, nr 2, s. 311-319Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mobile olfactory robots can be used in a number of relevant application areas where a better understanding of agas distribution is needed, such as environmental monitoring and safety and security related fields. In this paper wepresent a method to integrate the classification of odours together with gas distribution mapping. The resulting odourmap is then correlated with the spatial information collected from a laser range scanner to form a combined map.Experiments are performed using a mobile robot in large and unmodified indoor and outdoor environments. Multipleodour sources are used and are identified using only transient information from the gas sensor response. The resultingmulti level map can be used as a intuitive representation of the collected odour data for a human user.

  • 352.
    Lu, Hui
    et al.
    Dept Phys, E China Univ Sci & Technol, Shanghai, Peoples R China.
    Tu, Yaoquan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lin, Xian
    Dept Phys, E China Univ Sci & Technol, Shanghai, Peoples R China.
    Fang, Bin
    Inst Nucl Phys, E China Univ Sci & Technol, Shanghai, Peoples R China.
    Luo, Duanbin
    Dept Phys, E China Univ Sci & Technol, Shanghai, Peoples R China.
    Laaksonen, Aatto
    Div Phys Chem, Dept Mat & Environm Chem, Stockholm Univ, Stockholm, Sweden.
    Effects of laser irradiation on the structure and optical properties of ZnO thin films2010Inngår i: Materials letters (General ed.), ISSN 0167-577X, E-ISSN 1873-4979, Vol. 64, nr 19, s. 2072-2075Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The effects of laser irradiation on the surface microstructure and optical properties of ZnO films deposited on glass substrates were investigated experimentally and compared with those of thermal annealing. X-ray diffraction (XRD) and atomic force microscopy (AFM) measurements showed that the irradiation treatment with an Ar+ laser of 514 nm for 5 min improves the crystalline quality of ZnO thin films through increasing the grain size and enhancing the c-axis orientation, with the effects similar to those of the thermal annealing at 500 °C for 1 h. Laser irradiation was found to be more effective both for the relaxation of the residual compressive stress in the as-grown films and for the modification of the surface morphology. A significant increase in the UV absorption and a widening in the optical band-gap of the films were also observed after laser irradiation.

  • 353.
    Lundbäck, Jesper
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Eriksson, Christoffer
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Multiplayer RTS game2009Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This report is about the making of a very ambitious multiplayer strategy game. All games needs a name and after much thinking on different combinations of words from the almost obligatory latin language it was decided to name the game Armada Victor (AV). Armady Victor was entered in the Swedish Games Awards (SGA) yearly competition. A national competition for swedish students whose number of participants have grown over the years. The entity's description follows below:

    ”Armada Victor is a real time strategy game where you take on the role as the commander of an armada aboard the immense capital ship. The capital ship is your ship - lose it and you have been defeated. It is the only ship that may be controlled directly and with it is up to you to lead the way for the rest of your forces into triumph. The game is a multiplayer game which emphasizes offensive and tactical manoeuvres, instead of the resource managing and building more related to traditional real time strategy (RTS) games. Instead the armada is created and bought pre-game by an agreed number of points. The armadas selection ranges from fighters to heavy battleships and all manner of ships in between. With the help of boids (a behavioral model for flocking) and fuzzy logic all ships decides what their action will be depending on the situation. Cry havoc and let slip the boids of war!”

    The game never got as far in its development as the description would suggest and was never completed in time for the competition. However the ambition to complete it as a fully playable game still exists.

  • 354.
    Lundh, Robert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Plan-Based Configuration of a Group of Robots2006Licentiatavhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    Imagine the following situation. You give your favorite robot, named Pippi, the task to fetch a parcel that just arrived at your front door. While pushing the parcel back to you, she must travel through a door opening. Unfortunately, the parcel she is pushing is blocking her camera, giving her a hard time to see the door to cross. If she cannot see the door, she cannot safely push the parcel through the door opening. What would you as a human do in a similar situation? Most probably you would ask someone for help, someone to guide you through the door, as we ask for help then we need to park our car in a tight parking spot. Why not let the robots do the same? Why not let robots help each other. Luckily for Pippi, there is another robot, named Emil, vacuum cleaning the floor in the same room. Since Emil can view both Pippi and the door at the same time, he can guide pippi through the door, enabling her to deliver the parcel to you.

    This work is about societies of autonomous robots in which robots can help each other by offering information-producing functionalities. A functional configuration is a way to allocate and connect functionalities among robots. In general, different configurations can be used to solve the same task, depending on the current situation. For the work on configurations, we have three steps. The first step is to formally define the idea of functional configuration. Second, to show how configurations can be automatically generated and executed. The third step is to address the problem of when and how to change a configuration in response to changing conditions. In this licenciate thesis we report initial work that focus on the two first steps: the third step is subject of future work. We propose a formal definition of functional configurations, and we propose an approach based on artificial intelligence (AI) planning techniques to automatically generate a preferred configuration for a given task, environment, and set of resources. To illustrate these ideas, we describe an experimental system where these are implemented, and show two example of it in which two robots mutually help each other to address tasks. In the first example they help each other to cross a door, and in the second example they carry a bar together.

  • 355.
    Lundh, Robert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Robots that help each other: self-configuration of eistributed robot systems2009Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    Imagine the following situation. You give your favorite robot, named Pippi, the task to fetch a heavy parcel that just arrived at your front door. While pushing the parcel back to you, she must travel through a door. Unfortunately, the parcel she is pushing is blocking her camera, giving her a hard time to see the door. If she cannot see the door, she cannot safely push the parcel through it.

    What would you as a human do in a similar situation? Most probably you would ask someone for help, someone to guide you through the door, as we ask for help when we need to park our car in a tight parking spot. Why not let the robots do the same? Why not let robots help each other? Luckily for Pippi, there is another robot, named Emil, vacuum cleaning the floor in the same room. Since Emil has a video camera and can view both Pippi and the door at the same time, he can estimate Pippi's position relative to the door and use this information to guide Pippi through the door by wireless communication. In that way he can enable Pippi to deliver the parcel to you. The goal of this thesis is to endow robots with the ability to help each other in a similar way.

    More specifically, we consider distributed robot systems in which: (1) each robot includes modular functionalities for sensing, acting and/or processing; and (2) robots can help each other by offering those functionalities. A functional configuration of such a system is any way to allocate and connect functionalities configuration among the robots. An interesting feature of a system of this type is the possibility to use different functional configurations to make the same set of robots perform different tasks, or to perform the same task under different conditions. In the above example, Emil is offering a perceptual functionality to Pippi. In a different situation, Emil could offer his motion functionality to help Pippi push a heavier parcel.

    In this thesis, we propose an approach to automatically generate, at run time, a functional configuration of a distributed robot system to perform a given task in a given environment, and to dynamically change this configuration in response to failures. Our approach is based on artificial intelligence planning techniques, and it is provably sound, complete and optimal.

    In order to handle tasks that require more than one step (i.e., one configuration) to be accomplished, we also show how methods for automatic configuration can be integrated with methods for task planning to produce a complete plan were each step is a configuration. For the scenario above, generating a complete plan before the execution starts enables Pippi to know before hand if she will be able to get the parcel or not. We also propose an approach to merge configurations, which enables concurrent execution of configurations, thus reducing execution time.

    We demonstrate the applicability of our approach on a specific type of distributed robot system, called Peis-Ecology, and show experiments in which configurations and sequences of configurations are automatically generated and executed on real robots. Further, we give an experiment where merged configurations are created and executed on simulated robots.

  • 356.
    Lundh, Robert
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Karlsson, Lars
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Automatic configuration of multi-robot systems: planning for multiple steps2008Inngår i: Proceeding of the 2008 conference on ECAI 2008: 18th European conference on artificial intelligence / [ed] Malik Ghallab, Constantine D. Spyropoulos, Nikos Fakotakis, Nikos Avouris, Amsterdam: IOS Press , 2008, s. 616-620Konferansepaper (Fagfellevurdert)
    Abstract [en]

    We consider multi-robot systems where robots need to cooperate tightly by sharing functionalities with each other. There are methods for automatically configuring a multi-robot system for tight cooperation, but they only produce a single configuration. In this paper, we show how methods for automatic configuration can be integrated with methods for task planning in order to produce a complete plan were each step is a configuration. We also consider the issues of monitoring and replanning in this context, and we demonstrate our approach on a real multi-robot system, the PEIS-Ecology

  • 357.
    Lundh, Robert
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Karlsson, Lars
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Autonomous functional configuration of a network robot system2008Inngår i: Robotics and Autonomous Systems, ISSN 0921-8890, E-ISSN 1872-793X, Vol. 56, nr 10, s. 819-830Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We consider distributed systems of networked robots in which: (1) each robot includes sensing, acting and/or processing modular functionalities; and (2) robots can help each other by offering those functionalities. A functional configuration is any way to allocate and connect functionalities among the robots. An interesting feature of a system of this type is the possibility to use different functional configurations to make the same set of robots perform different tasks, or to perform the same task under different conditions. In this paper, we propose an approach to automatically generate at run time a functional configuration of a network robot system to perform a given task in a given environment, and to dynamically change this configuration in response to failures. Our approach is based on artificial intelligence planning techniques, and it is provably sound, complete and optimal. Moreover, our configuration planner can be combined with an action planner to deal with tasks that require sequences of configurations. We illustrate our approach on a specific type of network robot system, called Peis-Ecology, and show experiments in which a sequence of configurations is automatically generated and executed on real robots. These experiments demonstrate that our self-configuration approach can help the system to achieve greater autonomy, flexibility and robustness.

  • 358.
    Lundh, Robert
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Karlsson, Lars
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Saffiotti, Alessandro
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Dynamic self-configuration of an ecology of robots2007Inngår i: Intelligent Robots and Systems, 2007. IROS 2007. IEEE/RSJ International Conference on, NEW YORK: IEEE , 2007, s. 3409-3415Kapittel i bok, del av antologi (Annet vitenskapelig)
    Abstract [en]

    There is a tendency today toward the study of distributed systems consisting of many heterogeneous, networked, cooperating robotic devices. We refer to a system of this type as an ecology of robots. We call functional configuration of this ecology a way to allocate and connect functionalities among its robots. In general, the same ecology can perform different tasks by using different configuration. Moreover, the same task can often be solved using different configurations, and which is the best one depends on the available resources. This potential flexibility of a robot ecology is reduced by the fact that, in most current approaches, configurations are pre-programmed by hand. In this paper, we propose a plan-based approach to automatically generate a preferred configuration of a robot ecology given a task, environment, and set of resources. In contrast to previous approaches, the state of the ecology is automatically acquired at planning time, and it is monitored during execution in order to reconfigure if a functionality fails. We illustrate these ideas on a specific instance of an ecology of robots, called PEIS Ecology. We also show an experiment run on our PEIS Ecology testbed, in which a robot needs to reconfigure when the original configuration fails.

  • 359.
    Lundholm, Linus
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Dynamisk webbplats och säkerhet på internet2010Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Untreklam är en reklambyrå som främst fokuserar på trycksaker, och på grund av dess avsaknad av kompetens inom webbutveckling samt egen webbplats behövde de någon utomstående för att utveckla den. Syftet är att planera och utveckla en dynamisk webbplats med administratörssida som enkelt kan skötas av en person utan några större kunskaper inom webben. Utvecklingen av webbplatsen sker med hårdkodning utan hjälp av ett CMS-verktyg (Content Management System). Webbplatsen ska stämma överens med Untreklams grafiska profil samt återspegla deras önskade image. Dynamiska egenskaper kommer uppnås med programmeringsspråket PHP samt frågespråket SQL. Databasen som används är därför utav typen MySQL. Säkerhet är av yttersta vikt då man lägger ut en webbplats med dynamiska egenskaper, och man har tagit stor hänsyn till skydd mot attacker såsom SQL-injektion, och även använt hashalgoritmer för att försvåra stöld av användarkonton. Som ett extra tillval tas en del andra säkerhets- och hotaspekter upp på Internet, såsom malware, antivirusprogram, nätfiske och brandväggar.

  • 360. Lyubartsev, Alexander
    et al.
    Tu, Yaoquan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Laaksonen, Aatto
    Hierarchical multiscale modelling scheme from first principles to mesoscale2009Inngår i: Journal of Computational and Theoretical Nanoscience, ISSN 1546-1955, Vol. 6, nr 5, s. 951-959Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present a straight-forward implementation of a practical hierarchical multiscale modelling scheme which enables us to start from first-principles atomistic computer simulation and successively coarse-grain the model by leaving out uninteresting degrees of freedom. Using the Car-Parrinello method or our recently developed highly efficient tight-binding-like approximate density-functional quantum mechanical method,w e first perform first-principles simulations we obtain a set of atomistic pair-wise effective interaction potentials to be used as a force field with scaling up the system size 2–3 orders of magnitude. The atomistic simulations similarly provide a new set of effective potentials but at a chosen coarse-grain level suitable for large-scale mesoscopic or soft-matter simulations beyond the atomic resolution. Show several examples are shown of how this scheme is done based on effective interaction potentials to tie together the various scales of modelling.

  • 361.
    MacIntyre, Meghan M.
    et al.
    Dept Chem, Cape Breton Univ, Sydney NS, Canada.
    Martell, Jaime M.
    Dept Chem, Cape Breton Univ, Sydney NS, Canada.
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik. Sch Chem, Natl Univ Ireland Galway, Galway, Ireland.
    DFT study of five naphthalimide derivatives: Structures and redox properties2010Inngår i: Journal of Molecular Structure: THEOCHEM, ISSN 0166-1280, Vol. 941, nr 1-3, s. 133-137Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Geometries for five naphthalimide (NI) derivatives proposed as photoactive redox units in cancer treatment, have been optimized in the ground state, reduced and oxidized states using density functional theory (DFT) with the B3LYP hybrid functional and the 6-31G (d,p) basis set. The bond lengths of the N-[3-(dimethylamino)propyl]-1,8-naphthalimide derivative showed the most variation from the other four NI derivatives due to the nature of its substituent. An examination of atomic charges and spin densities shows in general that the ring carbons are most significant, except in the N-(propyl)-1,8-naphthalimide,3'-phosphoric acid derivative, where charges and densities are localized in the phosphate group. Single point energy calculations, both in vacuum and solution were performed for each NI derivative. The adiabatic and vertical electron affinities and ionization potentials are given for each of the NI derivatives in the ground state. The results suggest that none of the five NI derivatives studied can oxidize DNA nucleobases via direct electron transfer from the ground states, and that the dark toxicity of the compounds is thus most likely very low. (C)0 2009 Elsevier B.V. All rights reserved.

  • 362.
    Magnusson, Martin
    Örebro universitet, Akademin för naturvetenskap och teknik.
    The three-dimensional normal-distributions transform: an efficient representation for registration, surface analysis, and loop detection2009Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    This dissertation is concerned with three-dimensional (3D) sensing and 3D scan representation. Three-dimensional records are important tools in several disciplines; such as medical imaging, archaeology, and mobile robotics. This dissertation proposes the normal-distributions transform, NDT, as a general 3D surface representation with applications in scan registration, localisation, loop detection, and surface-structure analysis. After applying NDT, the surface is represented by a smooth function with analytic derivatives. This representation has several attractive properties.

    The smooth function representation makes it possible to use standard numerical optimisation methods, such as Newton’s method, for 3D registration. This dissertation extends the original two-dimensional NDT registration algorithm of Biber and Straßer to 3D and introduces a number of improvements. The 3D-NDT scan-registration algorithm is compared to current de facto standard registration algorithms. 3D-NDT scan registration with the proposed extensions is shown to be more robust, more accurate, and faster than the popular ICP algorithm. An additional benefit is that 3D-NDT registration provides a confidence measure of the result with little additional effort.

    Furthermore, a kernel-based extension to 3D-NDT for registering coloured data is proposed. Approaches based on local visual features typically use only a small fraction of the available 3D points for registration. In contrast, Colour-NDT uses all of the available 3D data. The dissertation proposes to use a combination of local visual features and Colour-NDT for robust registration of coloured 3D scans.

    Also building on NDT, a novel approach using 3D laser scans to perform appearance-based loop detection for mobile robots is proposed. Loop detection is an importantproblem in the SLAM (simultaneous localisation and mapping) domain. The proposed approach uses only the appearance of 3D point clouds to detect loops and requires nopose information. It exploits the NDT surface representation to create histograms based on local surface orientation and smoothness. The surface-shape histograms compress the input data by two to three orders of magnitude. Because of the high compression rate, the histograms can be matched efficiently to compare the appearance of two scans. Rotation invariance is achieved by aligning scans with respect to dominant surface orientations. In order to automatically determine the threshold that separates scans at loop closures from nonoverlapping ones, the proposed approach uses expectation maximisation to fit a Gamma mixture model to the output similarity measures.

    In order to enable more high-level tasks, it is desirable to extract semantic information from 3D models. One important task where such 3D surface analysis is useful is boulder detection for mining vehicles. This dissertation presents a method, also inspired by NDT, that provides clues as to where the pile is, where the bucket should be placed for loading, and where there are obstacles. The points of 3D point clouds are classified based on the surrounding surface roughness and orientation. Other potential applications include extraction of drivable paths over uneven surfaces.

  • 363.
    Magnusson, Martin
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Almqvist, Håkan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Consistent pile-shape quantification for autonomous wheel loaders2011Inngår i: 2011 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2011, s. 4078-4083Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents a study of approaches for selecting an efficient attack pose when loading piled materials with industrial construction vehicles. Automated handling of piled materials is a highly desired goal in many construction and mining applications. The main contributions of the paper are an experimental study of two novel approaches for selecting an attack pose from 3D data, compared to previously published approaches and extensions thereof. The outcome is based on quantitative validation, both with simulated data and data from a real-world scenario with nontrivial ground geometry.

  • 364.
    Magnusson, Martin
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Andreasson, Henrik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Nüchter, A.
    Jacobs University Bremen, Bremen, Germany.
    Lilienthal, Achim J.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Appearance-based loop detection from 3D laser data using the normal distributions transform2009Inngår i: IEEE International Conference on Robotics and Automation 2009 (ICRA '09), IEEE conference proceedings, 2009, s. 23-28Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    We propose a new approach to appearance based loop detection from metric 3D maps, exploiting the NDT surface representation. Locations are described with feature histograms based on surface orientation and smoothness, and loop closure can be detected by matching feature histograms. We also present a quantitative performance evaluation using two realworld data sets, showing that the proposed method works well in different environments.© 2009 IEEE.

  • 365.
    Magnusson, Martin
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Andreasson, Henrik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Nüchter, Andreas
    Jacobs University Bremen.
    Lilienthal, Achim J.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Automatic appearance-based loop detection from three-dimensional laser data using the normal distributions transform2009Inngår i: Journal of Field Robotics, ISSN 1556-4959, E-ISSN 1556-4967, Vol. 26, nr 11-12, s. 892-914Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We propose a new approach to appearance-based loop detection for mobile robots, usingthree-dimensional (3D) laser scans. Loop detection is an important problem in the simultaneouslocalization and mapping (SLAM) domain, and, because it can be seen as theproblem of recognizing previously visited places, it is an example of the data associationproblem. Without a flat-floor assumption, two-dimensional laser-based approaches arebound to fail in many cases. Two of the problems with 3D approaches that we address inthis paper are how to handle the greatly increased amount of data and how to efficientlyobtain invariance to 3D rotations.We present a compact representation of 3D point cloudsthat is still discriminative enough to detect loop closures without false positives (i.e.,detecting loop closure where there is none). A low false-positive rate is very important becausewrong data association could have disastrous consequences in a SLAM algorithm.Our approach uses only the appearance of 3D point clouds to detect loops and requires nopose information. We exploit the normal distributions transform surface representationto create feature histograms based on surface orientation and smoothness. The surfaceshape histograms compress the input data by two to three orders of magnitude. Becauseof the high compression rate, the histograms can be matched efficiently to compare theappearance of two scans. Rotation invariance is achieved by aligning scans with respectto dominant surface orientations. We also propose to use expectation maximization to fit a gamma mixture model to the output similarity measures in order to automatically determinethe threshold that separates scans at loop closures from nonoverlapping ones.Wediscuss the problem of determining ground truth in the context of loop detection and thedifficulties in comparing the results of the few available methods based on range information.Furthermore, we present quantitative performance evaluations using three realworlddata sets, one of which is highly self-similar, showing that the proposed methodachieves high recall rates (percentage of correctly identified loop closures) at low falsepositiverates in environments with different characteristics.

  • 366.
    Magnusson, Martin
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Nüchter, Andreas
    Jacobs University Bremen, Bremen, Germany; Knowledge Systems Research Group of the Institute of Computer Science, University of Osnabrück, Germany.
    Lörken, Christopher
    Institute of Computer Science, University of Osnabrück, Germany.
    Lilienthal, Achim J.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Hertzberg, Joachim
    Institute of Computer Science, University of Osnabrück, Germany.
    Evaluation of 3D registration reliability and speed: a comparison of ICP and NDT2009Inngår i: Proceedings of the 2009 IEEE international conference on Robotics and Automation, ICRA'09, IEEE conference proceedings, 2009, s. 2263-2268Konferansepaper (Fagfellevurdert)
    Abstract [en]

    To advance robotic science it is important to perform experiments that can be replicated by other researchers to compare different methods. However, these comparisons tend to be biased, since re-implementations of reference methods often lack thoroughness and do not include the hands-on experience obtained during the original development process. This paper presents a thorough comparison of 3D scan registration algorithms based on a 3D mapping field experiment, carried out by two research groups that are leading in the field of 3D robotic mapping. The iterative closest points algorithm (ICP) is compared to the normal distributions transform (NDT). We also present an improved version of NDT with a substantially larger valley of convergence than previously published versions.

  • 367.
    Mahmoud, Manal A. M.
    et al.
    Kyoto University.
    Kärrman, Anna
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Oono, Sayoko
    Kyoto University.
    Harada, Kouji H.
    Kyoto University.
    Koizumi, Akio
    Kyoto University.
    Polyfluorinated telomers in precipitation and surface water in an urban area of Japan2009Inngår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 74, nr 3, s. 467-472Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Although fluorotelomer alcohols (FTOHs) have been detected in various environmental matrices worldwide, no studies have been conducted to evaluate their concentrations in surface water or precipitation. Therefore, we developed a sensitive and reliable method to analyze various environmental aqueous samples for the presence of trace levels of 6:2 FTOH, 8:2 FTOH, 10:2 FTOH, 8:2 FTOAcr and 8:2 FTOMethacr FTOlefin using gas-chromatography/mass-spectrometry. The recoveries obtained using this method ranged from 57.8% to 78.2% and the detection limits were 0.5, 0.2, 0.2, 0.05 and 0.1 ng L−1 for 6:2 FTOH, 8:2 FTOH, 10:2 FTOH, 8:2 FTOAcr and 8:2 FTOMethacr, respectively. Liquid and suspended phases of the examined samples were analyzed. The analysis revealed presence of telomer alcohols from the liquid phase only. Of the FTOHs evaluated, 6:2 FTOH and 8:2 FTOMethacr FTOlefin were not found in any of the environmental samples. The average concentrations of 8:2 FTOH, 10:2 FTOH and 8:2 FTOAcr of the precipitation samples were 1.97, 0.82 and 0.21 ng L−1, respectively. In surface water samples, the highest concentrations of 8:2 FTOH, 10:2 FTOH and 8:2 FTOAcr were 3.38, 4.06 and 0.16 ng L−1, which were observed in samples from the Daini-Neyagawa, Yamato and Kanzaki rivers, respectively. The total concentration of FTOHs in wastewater treatment plant effluents (23.2 ng L−1) was much higher than that of surface water (10.8 ng L−1). Taken together, the results of this study indicate that FTOHs released into the air contaminate rain and that those released from water disposal sites contaminate surface water.

  • 368.
    Mannerling, Ann-Christine
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Simko, Myrtill
    Inst Cell Biol & Biosyst Technol, Div Environm Physiol, Univ Rostock, Rostock, Germany; Inst Technol Assessment, Austrian Acad Sci, Vienna, Austria.
    Hansson Mild, Kjell
    Dept Radiat Sci, Umeå Univ, Umeå, Sweden.
    Mattsson, Mats-Olof
    Örebro universitet, Akademin för naturvetenskap och teknik. Inst Cell Biol & Biosyst Technol, Div Environm Physiol, Univ Rostock, Rostock, Germany.
    Effects of 50-Hz magnetic field exposure on superoxide radical anion formation and HSP70 induction in human K562 cells2010Inngår i: Radiation and Environmental Biophysics, ISSN 0301-634X, E-ISSN 1432-2099, Vol. 49, nr 4, s. 731-741Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Epidemiological studies suggest a correlation between exposure to low-level extremely low-frequency (ELF) magnetic fields (MF) and certain cancers and neurodegenerative diseases. Experimental studies have not provided any mechanism for such effects, although at flux density levels significantly higher than the ones encountered in epidemiological studies, radical homoeostasis and levels of stress response proteins can be affected. Here, we report on the influence of MF exposure (50-Hz sine wave; 1 h; 0.025-0.10 mT; vertical or horizontal MF exposure direction) on different cellular parameters (proliferation, cell cycle distribution, superoxide radical anion, and HSP70 protein levels) in the human leukaemia cell line K562. The positive control heat treatment (42A degrees C, 1 h) did not affect either cell proliferation or superoxide radical anion production but caused accumulation of cells in the G2 phase and increased the stress protein HSP70. MF exposure (0.10 mT, 1 h) did not affect either cell cycle kinetics or proliferation. Both vertical and horizontal MF exposures for 1 h caused significantly and transiently increased HSP70 levels (> twofold), at several flux densities, compared to sham controls and also compared to heat treatment. This exposure also increased (30-40%) the levels of the superoxide radical anion, comparable to the positive control PMA. Addition of free radical scavengers (melatonin or 1,10-phenantroline) inhibited the MF-induced increase in HSP70. In conclusion, an early response to ELF MF in K562 cells seems to be an increased amount of oxygen radicals, leading to HSP70 induction. Furthermore, the results suggest that there is a flux density threshold where 50-Hz MF exerts its effects on K562 cells, at or below 0.025 mT, and also that it is the MF, and not the induced electric field, which is the active parameter.

  • 369.
    Mansouri, Masoumeh
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Constraint-Based Activity Recognition with Uncertainty2011Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    In the context of intelligent environments with the ability to provide support

    within our homes and in the workplace, the activity recognition process plays

    a critical role. Activity recognition can be applied to many real-life, humancentric

    problems such as elder care and health care. This thesis focuses on the

    recognizing high level human activity through a model driven approach to activity

    recognition, whereby a constraint-based domain description is used to

    correlate sensor readings to human activities. An important quality of sensor

    readings is that they are often uncertain or imprecise. Hence, in order to have

    a more realistic model, uncertainty in sensor data and flexibility and expressiveness

    should be considered in the model. These needs naturally arise in real

    world applications where considering uncertainty is crucial.

    In this thesis, a previously developed approach to activity recognition based

    on temporal constraint propagation is extended to accommodate uncertainty in

    the sensor readings and temporal relations between activities. The result of this

    extension is an activity recognition system in which each hypothesis deduced

    by the system is also weighted with a possibility degree.

    We validate our solutions to activity recognition with uncertainty both theoretically

    and experimentally, describing some explanatory examples.

     

  • 370. Marshall, Joshua
    et al.
    Barfoot, Timothy
    Larsson, Johan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Autonomous underground tramming for center-articulated vehicles2008Inngår i: Journal of Field Robotics, ISSN 1556-4959, Vol. 25, nr 6-7, s. 400-421Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper describes the design, implementation, and field testing of an infrastructureless system for autonomous tramming (or hauling) of a center-articulated underground mining vehicle. Such vehicles are ubiquitous in underground mining, and effective automation of their tramming function has been a sought-after technology for more than a decade. This paper reports on the successful development of a fast, reliable, and robust “autotramming” technology that does not require the installation of fixed infrastructure. Included are descriptions of the chosen control architecture, map-based localization technique, and the results of integration and field testing.

  • 371. Martinez, K.
    et al.
    Rivera-Austrui, J.
    Adrados, M. A.
    Abalos, M.
    Llerena, J. J.
    van Bavel, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Rivera, J.
    Abad, E.
    Uncertainty assessment of polychlorinated dibenzo-p-dioxins and dibenzofuran and dioxin-like polychlorinated biphenyl analysis in stationary source sample emissions in accordance with the impending European standard EN-1948 using fly ashes2009Inngår i: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1216, nr 31, s. 5888-5894Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The analysis of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) present in stack gas emissions and solid residues from incinerators will be mandatory in the foreseeable future. European standard EN-1948 is in the process of being updated through the addition of a new Part 4 related to the analysis of the 12 dl-PCBs. Therefore, either a comprehensive and reliable method capable of analyzing all of these 29 compounds (12 dl-PCBs and 17 2,3,7,8-PCDD/Fs) needs to be developed, or the existing PCDD/F analytical procedure must be adapted to include the dl-PCBs. This study has taken the latter approach of modifying PCDD/F methodology and in particular the fractionation step, by isolating dioxins and dl-PCBs into separate fractions ready for high resolution gas chromatography coupled to high resolution mass spectrometry (HRGC/HRMS) analysis. Results obtained from the analysis of Certified Reference Materials (CRM-490 and CRM-615) and fly ashes from the European Committee for Standardization (CEN) intercalibration study demonstrated that the proposed methodology is appropriate to determine the dl-PCBs in accordance with the impending European standard EN-1948. Uncertainty values obtained during the validation of the analytical methodology were 13% total I-TEQ (international Toxic Equivalent) for PCDD/Fs and 31% total WHO-TEQ (World Health Organization Toxic Equivalent) in the case of dl-PCBs. In addition, 'real' samples such as emissions and fly ashes were successfully analyzed following the proposed analytical method. (C) 2009 Elsevier B.V. All rights reserved.

  • 372.
    MARTURI, ANJANILAKSHMIKRISNANARESH
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Vision Based Grasp Planning for Robot Assembly2010Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
  • 373.
    Matxain, Jon M.
    et al.
    Euskal Herriko Unibertsitatea.
    Padro, Daniel
    Euskal Herriko Unibertsitatea.
    Ristilä, Mikael
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Strid, Åke
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Evidence of High dot OH Radical Quenching Efficiency by Vitamin B-62009Inngår i: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 113, nr 29, s. 9629-9632Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Molecules acting as antioxidants capable of scavenging reactive oxygen species (ROS) are of the utmost importance in the living cell. The antioxidative properties of pyridoxine (vitamin B6) have recently been discovered. Previous theoretical calculations have shown a high reactivity of pyridoxine toward hydroxyl radicals, where the latter preferably abstract H from either carbon of the two methanol substituents (C8 or C9). In this study, we have explored the reactivity of pyridoxine toward further hydroxyl radicals, considering as the first step the H abstraction from either C8 or C9, also including addition reactions and cyclization. Many of the reactions display similar ΔG, and hence, the quenching of hydroxyl radicals by pyridoxine may undergo different pathways leading to a mix of products. In addition, we observe that pyridoxine, under high hydroxyl radical concentrations, may scavenge up to eight radicals, supporting its observed high antioxidant activity.

  • 374.
    Memedi, Mevludin
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Mobile systems for monitoring Parkinson's disease2011Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis presents the development and evaluation of IT-based methods and systems for supporting assessment of symptoms and enabling remote monitoring of Parkinson‟s disease (PD) patients. PD is a common neurological disorder associated with impaired body movements. Its clinical management regarding treatment outcomes and follow-up of patients is complex. In order to reveal the full extent of a patient‟s condition, there is a need for repeated and time-stamped assessments related to both patient‟s perception towards common symptoms and motor function. In this thesis, data from a mobile device test battery, collected during a three year clinical study, was used for the development and evaluation of methods. The data was gathered from a series of tests, consisting of selfassessments and motor tests (tapping and spiral drawing). These tests were carried out repeatedly in a telemedicine setting during week-long test periods. One objective was to develop a computer method that would process tracedspiral drawings and generate a score representing PD-related drawing impairments. The data processing part consisted of using the discrete wavelet transform and principal component analysis. When this computer method was evaluated against human clinical ratings, the results showed that it could perform quantitative assessments of drawing impairment in spirals comparatively well. As a part of this objective, a review of systems and methods for detecting the handwriting and drawing impairment using touch screens was performed. The review showed that measures concerning forces, accelerations, and radial displacements were the most important ones in detecting fine motor movement anomalies. Another objective of this thesis work was to design and evaluate an information system for delivering assessment support information to the treating clinical staff for monitoring PD symptoms in their patients. The system consisted of a patient node for data collection based on the mobile device test battery, a service node for data storage and processing, and a web application for data presentation. A system module was designed for compiling the test battery time series into summary scores on a test period level. The web application allowed adequate graphic feedback of the summary scores to the treating clinical staff. The evaluation results for this integrated system indicate that it can be used as a tool for frequent PD symptom assessments in home environments.

  • 375.
    Memedi, Mevludin
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Westin, Jerker
    Academy of Industry and Society, Computer Engineering, Dalarna University, Borlänge, Sweden.
    Methods for detection of handwriting/drawing impairment using inputs from touch screens2011Inngår i: Recent Patents on Signal Processing, ISSN 1877-6124, Vol. 1, nr 2, s. 156-162Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Fine motor dysfunction in patients with movement disorders, such as Parkinson’s disease, is characterized by slowness of movements, decrease of reaction time and involuntary movements. In this article, recent patents on detecting and assessing the said dysfunction are reviewed; their implementation in telemedicine settings, design considerations and ability to assist in dose and time adjustments are discussed. These patents explain application of signal processing techniques in analysis and interpretation of digitized handwriting/drawing information of individuals based on data gathered using touch screens. The study reveals that measures concerning forces, accelerations and radial displacements are the most relevant measurements to detect fine movement anomalies. These findings demonstrate that digitized analysis of handwriting/drawing movements may be useful in clinical trials evaluating fine motor control. This review further depicts the role of employing event-based data acquisition and signal processing techniques suitable for nonstationary signals, such as Wavelet transform, in systems for patient home-monitoring.

  • 376.
    Memedi, Mevludin
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik. Department of Economy and Society, Computer Engineering, Dalarna University, Borlänge, Sweden.
    Westin, Jerker
    Department of Economy and Society, Computer Engineering, Dalarna University, Borlänge, Sweden.
    Nyholm, Dag
    Department of Neuroscience, Neurology, Uppsala University, Uppsala, Sweden.
    Dougherty, Mark
    Department of Economy and Society, Computer Engineering, Dalarna University, Borlänge, Sweden.
    Groth, Torgny
    Department of Medical Sciences, Biomedical Informatics and Engineering, Uppsala University, Uppsala, Sweden.
    A web application for follow-up of results from a mobile device test battery for Parkinson's disease patients2011Inngår i: Computer Methods and Programs in Biomedicine, ISSN 0169-2607, E-ISSN 1872-7565, Vol. 104, nr 2, s. 219-226Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper describes a web-based system for enabling remote monitoring of patients with Parkinson's disease (PD) and supporting clinicians in treating their patients. The system consists of a patient node for subjective and objective data collection based on a handheld computer, a service node for data storage and processing, and a web application for data presentation. Using statistical and machine learning methods, time series of raw data are summarized into scores for conceptual symptom dimensions and an “overall test score” providing a comprehensive profile of patient's health during a test period of about one week. The handheld unit was used quarterly or biannually by 65 patients with advanced PD for up to four years at nine clinics in Sweden. The IBM Computer System Usability Questionnaire was administered to assess nurses’ satisfaction with the web application. Results showed that a majority of the nurses were quite satisfied with the usability although a sizeable minority were not. Our findings support that this system can become an efficient tool to easily access relevant symptom information from the home environment of PD patients.

  • 377.
    Meyer, Björn
    Örebro universitet, Akademin för naturvetenskap och teknik.
    STUDY OF TRUNNION CAPS2011Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    This thesis compiles information of a kind of bracket named “Trunnion cap” which is used at some of the loaders and trucks that are developed at Atlas Copco Rock Drills AB in Örebro, the information is needed to create a technical guideline for design of new trunnion caps. The thesis is limited to investigate trunnion caps that are used to attach steering cylinders on six different vehicles, MT436B, MT5020, MT6020, ST1030, ST14 and ST1520.

    It investigates what angles the force generated by the steering cylinders acts from, which varies from a range of 6 to 96 degrees depending on which vehicle and frame it is. The forces generated by the steering cylinder have also been calculated regarding the maximum pressure which is between 21,5 and 30 MPa for the different vehicles.

    Any kind of useful information from customers has also been searched partly by asking employees at Atlas Copco customer centres around the world if they are aware of any occasions were trunnion caps or bolts to trunnion caps have broke down. The results indicate that no problems exist today and that old problems had to do with lack of service. Even the internal databases for service reports have been searched for failures that regard parts to trunnion caps but no relevant information was found.

    The tolerances for the holes in the trunnion caps and to the pins that are assembled to the trunnion caps has also been identified with a result that vary, some assemblies have a tight fitting while others have a loose fitting.

    Finally has the availability of bolts with property class 8.8 and 10.9 been investigated where it has been noticed that the lead time for bolts with property class 8.8 more often is shorter than it is for bolts with property class 10.9.

  • 378.
    Miljkovic, Vladimir D.
    et al.
    Dept Appl Phys, Chalmers, Gothenburg, Sweden.
    Pakizeh, Tavakol
    Dept Appl Phys, Chalmers, Gothenburg, Sweden; Dept Elect Engn, KN Toosi Univ Technol, Tehran, Iran.
    Sepulveda, Borja
    Res Ctr Nanosci & Nanotechnol CIN2, Nanobiosensors & Mol Nanobiophys Grp, CSIC ICN, Bellaterra, Spain.
    Johansson, Peter
    Örebro universitet, Akademin för naturvetenskap och teknik. Dept Appl Phys, Chalmers, Gothenburg, Sweden.
    Kall, Mikael
    Dept Appl Phys, Chalmers, Gothenburg, Sweden.
    Optical Forces in Plasmonic Nanoparticle Dimers2010Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 114, nr 16, s. 7472-7479Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present calculations of the optical forces between two metal nanospheres forming a hybridized plasmonic chiller. We consider homo- and heterodimers and investigate different plane wave illumination configurations. The forces between the particles are calculated using kill Mie theory combined with the Maxwell stress tensor (MST) formalism, as well as by approximate methods, such as the Lorentz force (LF) approach taken in the dipole limit and calculations based on an optical potential. We show that the simplified calculation schemes can lead to serious errors in the case of strongly interacting particles and low damping. In particular, we find that equilibrium configurations, corresponding to vanishing optical forces, only are possible for homodimers illuminated in the end-fire configuration and for heterodimers, although multipolar effects and clamping radically reduce the repulsive interactions in the latter case.

  • 379. Miljkovic, Vladimir D.
    et al.
    Shegai, Timur
    Käll, Mikael
    Johansson, Peter
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Mode-specific directional emission from hybridized particle-on-a-film plasmons2011Inngår i: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 19, nr 14, s. 12856-12864Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We investigate the electromagnetic interaction between a gold nanoparticle and a thin gold film on a glass substrate. The coupling between the particle plasmons and the surface plasmon polaritons of the film leads to the formation of two localized hybrid modes, one low-energy. film-like. plasmon and one high-energy plasmon dominated by the nanoparticle. We find that the two modes have completely different directional scattering patterns on the glass side of the film. The high-energy mode displays a characteristic dipole emission pattern while the low-energy mode sends out a substantial part of its radiation in directions parallel to the particle dipole moment. The relative strength of the two radiation patterns vary strongly with the distance between the particle and the film, as determined by the degree of particle-film hybridization. (C) 2011 Optical Society of America

  • 380.
    Minata, Mutsuko
    et al.
    Grad Sch Med, Dept Hlth & Environm Sci, Kyoto Univ, Kyoto, Japan.
    Harada, Kouji H.
    Grad Sch Med, Dept Hlth & Environm Sci, Kyoto Univ, Kyoto, Japan.
    Kärrman, Anna
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Hitomi, Toshiaki
    Grad Sch Med, Dept Hlth & Environm Sci, Kyoto Univ, Kyoto, Japan.
    Hirosawa, Michi
    Grad Sch Med, Dept Hlth & Environm Sci, Kyoto Univ, Kyoto, Japan.
    Murata, Mariko
    Grad Sch Med, Dept Environm & Mol Med, Tsu, Mie Univ, Mie, Japan.
    Gonzalez, Frank J.
    Lab Metab, NIH, National Cancer Institute, Bethesda MD, USA.
    Koizumi, Akio
    Grad Sch Med, Dept Hlth & Environm Sci, Kyoto Univ, Kyoto, Japan.
    Role of Peroxisome Proliferator-activated Receptor-alpha in Hepatobiliary Injury Induced by Ammonium Perfluorooctanoate in Mouse Liver2010Inngår i: Industrial Health, ISSN 0019-8366, E-ISSN 1880-8026, Vol. 48, nr 1, s. 96-107Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Peroxisome proliferator-activated receptor-alpha (PPAR alpha) has been suggested to protect against chemically induced hepatobiliary injuries in rodents. This function could mask the potential toxicities of perfluorooctanoic acid (PFOA) that is an emerging environmental contaminant and a weak ligand of PPAR alpha. However its function has not been clarified. In this study, PFOA was found to elicit hepatocyte and bile duct injuries in Ppar alpha-null mice after 4 wk treatment with PFOA ammonium salt (0, 12.5, 25, 50 mu mol/kg/d, gavage). In wild-type mice, PFOA caused major hepatocellular damage dose-dependently and minor cholangiopathy observed only at 25 and 50 mu mol/kg. In treated Ppar alpha-null mice, PFOA produced marked fat accumulation, severe cholangiopathy, hepatocellular damage and apoptotic cells especially in bile ducts. Oxidative stress was also increased 4-fold at 50 mu mol/kg and TNF-alpha mRNA was upregulated more than 3-fold at 25 mu mol/kg in Ppar alpha-null mice. Biliary bile acid/phospholipid ratios were higher in Ppar alpha-null mice than in wild-type mice. Results from these studies suggest that PPAR alpha is protective against PFOA and have a critical role in drug induced hepatobiliary injury.

  • 381.
    Modig, Carina
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Raldúa, Demetrio
    Cerdà, Joan
    Olsson, Per-Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Analysis of vitelline envelope synthesis and composition during early oocyte development in gilthead seabream (Sparus aurata)2008Inngår i: Molecular Reproduction and Development, ISSN 1040-452X, E-ISSN 1098-2795, Vol. 75, nr 8, s. 1351-1360Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The oocyte vitelline envelope (VE) of gilthead seabream is composed of four known zona pellucida (ZP) proteins, ZPBa, ZPBb, ZPC, and ZPX. We have previously shown that the gilthead seabream ZP proteins are differentially transcribed in liver and ovary, with the expression in liver being under estrogenic control. However, although mRNA was found in both liver and ovary, only low ZPBa protein levels were detected in liver and plasma. Using isoform-specific ZP antibodies we show that ZPBa and ZPX translation products are present in the cytosol of stage I and II oocytes. In addition, the zpBa and zpX mRNAs were detected in early developing oocytes. During oocyte growth (vitellogenesis), the VE increased in thickness (>10 µm), and we show that the four ZP isoforms are present in different regions of the VE. ZPX was detected closest to the oocyte plasma membrane while the intermediate region was composed of ZPBa, ZPBb, and ZPC. At the outer layer, only ZPC was detected. When oocytes reach the fully grown stage they resume meiosis and hydration. As the oocyte expands, thinning to 4 µm, the VE acquire a striped and compact appearance at the electron microscopy level. This study provides further evidence for the oocyte origin of some ZP proteins in the gilthead seabream and suggests that the ZP proteins are differentially distributed within the VE. Mol. Reprod. Dev. 75: 1351-1360, 2008.

  • 382.
    Morfeldt, Johannes
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Optically Selective Surfaces in low concentrating PV/T systems2009Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    One of the traditional approaches to reduce costs of solar energy is to use inexpensive reflectors to focus the light onto highly efficient solar cells. Several research projects have resulted in designs, where the excess heat is used as solar thermal energy.

    Unlike a solar thermal system, which has a selective surface to reduce the radiant heat loss, a CPV/T (Concentrating PhotoVoltaic/Thermal) system uses a receiver covered with solar cells with high thermal emittance.

    This project analyzes whether the heat loss from the receiver can be reduced by covering parts of the receiver surface, not already covered with solar cells, with an optically selective coating. Comparing different methods of applying such a coating and the long-term stability of low cost alternatives are also part of the objectives of this project.

    To calculate the heat loss reductions of the optically selective surface coating a mathematical model was developed, which takes the thermal emittances and the solar absorptances of the different surfaces into account. Furthermore, a full-size experiment was constructed to verify the theoretical predictions.

    The coating results in a heat loss reduction of approximately 20 % in such a CPV/T system and one of the companies involved in the study is already changing their design to make use of the results.

  • 383.
    Murcia Arco, Sergio
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Visualization of through plane bloodflow measurements obtained fromphase contrast MRI2009Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    This project was ordered by Per Thunberg, Department of Biomedical Engineering in Örebro University Hospital in the Spring 2009.

    This project’s aim is to combine in one image-layer two sources of, one source is anatomy images that represents body-parts and the other source is velocity images that represent blood flow though the body. This project’s purpose if for medical use. Further, taking into consideration the combination of Magnetic Resonance Images and the high rate of computation that the computers have nowadays it is possible to obtain appropriate result in real-time that can be useful for doctors.

    The purpose of this project was to develop an application in Matlab® for displaying combined MRI images. The images are taken from a Magnetic Resonance machine during phase contrast. The image acquisition itself is out of scope of the project work. However, the images/videos are stored in the DICOM medical format, and these images are the ones that need to be combined and displayed.

    When both images are combined, some data of every image has to be displayed to the user (doctor) showing only the important information the user wants. Some image techniques are used to achieve this, in particular pseudocoloring and the Volume Rendering Technique. Once the two types of images can be combined into a single image then the next step is to achieve this for frames, which are multiple images over time which will loop like a movie-player does. And there are some other improvements in order to make it easier for the users (doctors) to retrieve useful information.

    Some improvements to visualization the information that doctors can get in every frame were added, like how to set an area of interest for only coloring the specified area they want to check and not coloring the area not selected, or how to change the color map to another one if they experience some problems with the actual colors they have. Further, functionalities have been added which allows the user to pause, select, go forward or backward the instant of time they want by clicking on a slide-bar that determines the actual reproduction moment.

  • 384.
    Musa, Klefah A. K.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Photodegradation Mechanism of Nonsteroidal Anti-Inflammatory Drugs Containing Thiophene Moieties: Suprofen and Tiaprofenic Acid2009Inngår i: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 113, nr 32, s. 11306-11313Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The photodegradation of nonsteroid anti-inflammatory drugs suprofen, 2-[4-(2-thienoyl)phenyl]propionic acid, and tiaprofenic acid, 2-(5-benzoyl-2-thienyl)propanoic acid, is studied by means of density functional theory. Besides the redox properties of the neutral species, we report on absorption spectra and degradation pathways involving excitation, intersystem crossing to the T-1 state. and spontaneous decarboxylation of the deprotonated species of each drug. The energetics and properties of the suprofen and tiaprofenic acid systems are found to be very similar to those of the highly photolabile benzyl analogue ketoprofen. Mechanisms leading to the formation of a closed-shell decarboxylated ethyl species, as well as peroxyl radicals capable of initiating lipid peroxidation reactions, are discussed.

  • 385.
    Musa, Klefah A. K.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Photodegradation mechanism of the common non-steroid anti-inflammatory drug diclofenac and its carbazole photoproduct2009Inngår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 11, nr 22, s. 4601-4610Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Diclofenac (DF) is a widely used non-steroid anti-inflammatory drug, associated with a range of side effects. The phototoxicity of DF is studied herein employing computational quantum chemistry at the B3LYP/6-31G(d,p) level of theory. The results show that the drug readily absorbs radiation from the UV-region. The deprotonated form spontaneously dechlorinates from its triplet state leading to ring closure and formation of an active photoproduct: chlorocarbazole acetic acid, CCA. The formed CCA is also photodegraded easily from its deprotonated triplet state. Photodegradation routes of deprotonated CCA are decarboxylation (barrier less than 4.5 kcal mol(-1)) and dechlorination (barrier around 6.2 kcal mol(-1)). The energy barrier required for dechlorination to take place from the neutral from is about 20 kcal mol(-1). The differences between the molecular orbitals of the neutral and the deprotonated forms of DF and CCA and spectra obtained using time-dependent density-functional theory (TD-DFT), in addition to the different radical and oxygenated intermediate species formed during the photodegradation mechanism, are discussed in more detail. The theoretical results obtained herein are in line with the experimental results available to date.

  • 386.
    Musa, Klefah A. K.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Photophysical and photochemical properties and photodehalogenation of antibiotic drug lomefloxacinManuskript (preprint) (Annet vitenskapelig)
  • 387.
    Musa, Klefah A. K.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Theoretical assessment of norfloxacin redox and photochemistry2009Inngår i: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 113, nr 40, s. 10803-10810Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Norfloxacin, 1-ethyl-6-fluoro-1,4-dihydo-4-oxo-7-(1-piperazinyl)-3-quinolinecarboxyli c acid, NOR, is an antibiotic drug from the fluoroquinoline family. The different protonation states of this drug formed throughout the pH range is studied by means of density functional theory (DFT) and the spectra of the NOR species computed using time-dependent DFT. Details about their photochemistry are obtained from investigating the highest occupied and lowest unoccupied molecular orbitals. The predominant species under physiological pH, the zwitterion, is the most photoliable one, capable of producing singlet oxygen or/and superoxide radical anions from its triplet state. In addition, the main photodegradation step, defluorination, occurs more easily from this species compared with the other forms. The defluorination from the excited triplet state requires passing a barrier of 16.3 kcal/mol in the case of the zwitterion. The neutral and cationic forms display higher transition barriers, whereas the reaction path of defluorination is completely endothermic for the anionic species. The theoretical results obtained herein are in line with previous experimental data.

  • 388.
    Musa, Klefah A. K.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Palawi, Viraja R.
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    New non-steroidal anti-inflammatory molecules with reduced photodegradation side effects and enhanced COX-2 selectivityManuskript (preprint) (Annet vitenskapelig)
  • 389.
    Musa, Klefah A. K.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Palwai, Viraja R.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    New nonsteroidal anti-inflammatory molecules with reduced photodegradation side effects and enhanced COX-2 selectivity2011Inngår i: International Journal of Quantum Chemistry, ISSN 0020-7608, E-ISSN 1097-461X, Vol. 111, nr 6, s. 1184-1195Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used as antipyretic, analgesic, and anti-inflammatory agents. However, they are also associated with a range of side effects, from phototoxicity due to excited state induced decarboxylation to severe conditions in the gastrointestinal tract caused by inhibition of the COX-1 isoform of the target cyclooxygenase enzyme. In the current work, new derivatives of the three NSAIDs ketoprofen, ibuprofen, and naproxen were designed. Their photochemistry was explored using hybrid-density functional theory (B3LYP/6-31G(d,p)) and time-dependent (TD) DFT, showing that the compounds will have significantly reduced propensity to decarboxylate from the first excited triplet state. In addition, docking studies were carried out for these new molecules to explore their activity and selectivity toward the two isoforms of the COX enzyme. The results show that most compounds have increased activity toward the COX enzymes, and in general are more selective toward the COX-2 target isoform. The results from this study suggest that the new modified molecules could be used in the future as NSAIDs with considerably reduced side effects.

  • 390.
    Musa, Klefah Abrahem Klefah
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Computational studies of photodynamic drugs, phototoxic reactions and drug design2009Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The most important criterion when designing new drugs or improving old ones in order to prevent side effects or at least diminish them is drug safety. Treatment of all diseases generally needs use of either topical application or systemic medications (transported in the blood) during a certain period of time. These treatments are associated with a number of adverse effects. Photosensitivity is one of those side effects, with phototoxicity as one of the photosensitivity disorders. This adverse side effect arises because of a reaction between UV or visible-light and the drug molecule, its active form or photoproduct(s). Due to phototoxic side effect, unexpected symptoms varying from just a simple rash to severe cutaneous affectations can appear. Furthermore, biomolecular damage occurs once the drug-light interaction takes place persistently and ends with cell death.

    Several drug families, such as over-the-counter drugs in the non-steroidal anti-inflammatory drug family of 2-arylpropionic acid derivatives, or prescription required fluoroquinolone drugs, have the capability to absorb mainly UV light radiation which in turn causes different phototoxic reactions by forming radical derivatives, reactive oxygen species or both. These may effect DNA, protein and lipid cell components leading to photogenotoxicity, photoallergy and lipid peroxidation, respectively. The photodegradation mechanisms of drugs belonging to the above mentioned families including ketoprofen, ibuprofen, flurbiprofen, naproxen, the active form of nabumetone, diclofenac and its main photoproduct, suprofen, tiaprofenic acid, naphazoline, norfloxacin and lomefloxacin are investigated in more detail in this thesis.

    The results obtained by computational density functional theory (DFT) and time-dependent-DFT (TD-DFT) are in line with experimental data available to date. The studies provide detailed insight into the molecular basis and understanding of the full photodegradation mechanisms of drugs mentioned above. This also plays an important role in preventing or at least reducing the phototoxic adverse effects by enabling the development of safe drugs in this area. Hence, new modified non-steroid anti-inflammatory molecules were designed by computational techniques. Obtained results suggest possibility of their future usage as pharmaceuticals with reduced photodegradation and cyclooxygenase 1 induced adverse side effects compared to the parent compounds.

  • 391.
    Musa, Klefah A.K.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Photochemical and photophysical properties, and photodegradation mechanism, of the non-steroid anti-inflammatory drug Flurbiprofen2009Inngår i: Journal of Photochemistry and Photobiology A: Chemistry, ISSN 1010-6030, E-ISSN 1873-2666, Vol. 202, nr 1, s. 48-56Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The photodegradation mechanism of the widely used non-steroidal anti-inflammatory drug 2-(4-phenyl-3-fluorophenyl) propanoic acid, Flurbiprofen, and its photochemical and photophysical properties have been investigated by means of computational quantum chemistry at the DFT-B3LYP/6-31G(d,p) level. Comparison of computed and experimental singlet and triplet–triplet absorption spectra point to that most experiments, using a range of different solvents, are conducted on the neutral, protonated form of Flurbiprofen. The deprotonated acid, which should dominate at physiological pH, shows no sign of decarboxylation from the lowest singlet excited states, whereas from its first excited triplet state this should readily occur by passing over an energy barrier of <0.5 kcal/mol. Further reactions in the proposed photodegradation mechanism, after decarboxylation, as well as the probability for reactive oxygen species formation are discussed in detail. The generation of the corresponding peroxyl radical from the decarboxylated radical and molecular oxygen is strictly exergonic and occurs without barrier under aerobic conditions. The thus formed peroxyl radical will in turn be capable of initiating propagating lipid peroxidation processes.

  • 392.
    Musa, Klefah A.K.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Theoretical Study of the Phototoxicity of Naproxen and the Active Form of Nabumetone2008Inngår i: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 112, nr 43, s. 10921-10930Artikkel i tidsskrift (Fagfellevurdert)
  • 393. Nehrenheim, E.
    et al.
    Odlare, M.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Retention of 2,4,6-trinitrotoluene and heavy metals from industrial waste water by using the low cost adsorbent pine bark in a batch experiment2011Inngår i: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 64, nr 10, s. 2052-2058Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Pine bark is a low cost sorbent originating from the forest industry. In recent years, it has been found to show promise as an adsorbent for metals and organic substances in contaminated water, especially landfill leachates and storm water. This study aims to investigate if pine bark can replace commercial adsorbents such as active carbon. An industrial effluent, collected from a treatment plant of a demilitarization factory, was diluted to form concentration ranges of contaminants and shaken with pine bark for 24 hours. Metals (e.g. Pb, Zn, Cd, As and Ni) and explosives, e. g., 2,4,6-trinitrotoluene (TNT), were analysed before and after treatment. The aim of the experiment was twofold; firstly, it was to investigate whether metals are efficiently removed in the presence of explosives and secondly, if adsorption of explosive substances to pine bark was possible. Langmuir and Freundlich isotherms were used to describe the adsorption process where this was possible. It was found that metal uptake was possible in the presence of TNT and other explosive contaminants. The uptake of TNT was satisfactory with up to 80% of the TNT adsorbed by pine bark.

  • 394.
    Nehrenheim, Emma
    et al.
    Mälardalens högskola, Västerås, Sweden.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Odlare, Monica
    Mälardalens högskola, Västerås, Sweden.
    The effect of different components in waste water on the adsorption of heavy metals onto pine bark (Pinus Silvestris)2011Konferansepaper (Fagfellevurdert)
  • 395.
    Nehrenheim, Emma
    et al.
    Mälardalens högskola, Västerås, Sweden.
    Odlare, Monica
    Mälardalens högskola, Västerås, Sweden.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Retention of 2,4,6-trinitrotoluene (TNT) and heavy metals from industrial waste water by using the low cost adsorbent pine bark in a batch experiment2009Konferansepaper (Fagfellevurdert)
  • 396.
    Nehrenheim, Emma
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology, Västerås, Sweden.
    Odlare, Monica
    Mälardalen University, School of Sustainable Development of Society and Technology, Västerås, Sweden.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Rodriguez, Adrian
    Mälardalen University, School of Sustainable Development of Society and Technology, Västerås, Sweden.
    Treatment of metal contaminated water by using pine bark: a multivatiate approach2009Konferansepaper (Fagfellevurdert)
  • 397.
    Netz, Helena
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Förstudie: Internt moln: En fallstudie för effektivare IT-administration2011Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    This is a report of a prestudy commissioned by a medium-sized Swedish company before an imminent major change in IT systems. The change aims to provide a simplified IT administration within the company through a cloud-based approach.

    The preliminary study provides an interpretation of the concept of cloud computing. It also covers a review of different models to use in order to achieve an internal cloud. Suggestions on how to proceed with the change process are also provided, and which models might be appropriate for the specific company.

  • 398.
    Nilsson, Helena
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Kärrman, Anna
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Rotander, Anna
    Örebro universitet, Akademin för naturvetenskap och teknik.
    van Bavel, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lindström, Gunilla
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Westberg, Håkan
    Örebro universitet, Akademin för naturvetenskap och teknik. Örebro University Hospital, Örebro, Sweden.
    Inhalation exposure to fluorotelomer alcohols yield perfluorocarboxylates in human blood?2010Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 44, nr 19, s. 7717-7722Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Levels of perfluorinated carboxylates (PFCAs) in different environmental and biological compartments have been known for some time, but the routes of exposure still remain unclear. The opinions are divergent whether the exposure to general populations occurs mainly indirect through precursor compounds or direct via PFCAs. Previous results showed elevated blood levels of PFCAs in ski wax technicians compared to a general population. The objective of this follow-up study was to determine concentrations of PFCAs, perfluorosulfonates (PFSAs), and fluorotelomer alcohols (FTOHs), precursor compounds that are known to degrade to PFCAs, in air collected in the breathing zone of ski wax technicians during work. We collected air samples by using ISOLUTE ENV+ cartridges connected to portable air pumps with an air flow of 2.0 L min(-1). PFCAs C5-C11 and PFSAs C4, C6, C8, and C10 were analyzed using LC-MS/MS and FTOHs 6:2, 8:2, and 10:2 with GC-MS/MS. The results show daily inhalation exposure of 8:2 FTOH in mu g/m(3) air which is up to 800 times higher than levels of PFOA with individual levels ranging between 830-255000 ng/m(3) air. This suggests internal exposure of PFOA through biotransformation of 8:2 FTOH to PFOA and PFNA in humans.

  • 399.
    Nilsson, Helena
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Kärrman, Anna
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Westberg, Håkan
    Örebro universitet, Akademin för naturvetenskap och teknik. Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro, Sweden.
    Rotander, Anna
    Örebro universitet, Akademin för naturvetenskap och teknik.
    van Bavel, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lindström, Gunilla
    Örebro universitet, Akademin för naturvetenskap och teknik.
    A time trend study of significantly elevated perfluorocarboxylate levels in humans after using fluorinated ski wax2010Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 44, nr 6, s. 2150-2155Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A time trend study focusing on ski waxing technicians' exposure to perfluorinated chemicals (PFCs) from fluorinated wax fumes was performed in 2007/2008. Levels of eight perfluorocarboxylates and three perfluorosulfonates were analyzed in monthly blood samples from eight technicians, Samples were collected before the ski season, i.e., preseason, then at four AS World Cup competitions in cross country skiing, and finally during an unexposed 5-month postseason period. The perfluorinated carboxylates perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnDA) bioaccumulate, and continued exposure may contribute to elevated levels in ski technicians compared to the general population. The wax technicians' median blood level of PFOA is 112 ng/mL compared to 2.5 ng/mL in the general Swedish population. A significant correlation was found between number of working years and levels of perfluorocarboxylates. The PFOA levels in three technicians with "low" initial levels of PFOA (< 10.0 ng/mL in preseason blood) increased by 254, 134, and 120%, whereas five technicians with "high" initial levels (> 100 ng/mL in preseason sample) were at steady state. PFHxA is suggested to have a short half-life in humans relative the other perfluorocarboxylates. The levels of perfluorosulfonates were unaffected by the wax exposure.

  • 400.
    Nilsson, Maria
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Capturing semi-automated decision making: the methodology of CASADEMA2010Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    This thesis presents a new methodology named CASADEMA (CApturing Semi-Automated DEcision MAking) which captures the interaction between humans and the technology they use to support their decision-making within the domain of Information Fusion. We are particularly interested in characterising the interaction between human decision makers and artefacts in semi-automated fusion processes. In our investigation we found that the existing approaches are limited in their ability to capture such interactions in sufficient detail. The presented method is built upon a distributed-cognition perspective. The use of this particular theoretical framework from cognitive science enables the method to take into account not only the role of the data captured in the physical and digital artefacts of the fusion system (e.g., radar readings, information from a fax or database, a piece of paper, etc.), but also the cognitive support function of the artefacts themselves (e.g., as an external memory) as part of the fusion process. That is, the interdependencies between the fusion process and decision-making can be captured. This thesis thus contributes to two main fields. Firstly, it enables, through CASADEMA, a distributed-cognition perspective of fusion processes in the, otherwise, rather technology-oriented field of Information Fusion. This has important conceptual implications, since it views fusion processes as extending beyond the boundary of physical/computer systems, to include humans, technology, and tools, as well as the interactions between them. It is argued that a better understanding of these interactions can lead to a better design of fusion processes, making CASADEMA an important contribution to the information fusion field. Secondly, the thesis provides, again in the form of CASADEMA, a practical application of the distributed-cognition theoretical framework. Importantly, the notations and definitions introduced in CASADEMA structure the otherwise currently rather loosely defined concepts and approaches in distributed cognition research. Hence, the work presented here also contributes to the fields of cognitive science and human-computer interaction.

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