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  • Lind, Martin
    et al.
    Örebro University, School of Humanities, Education and Social Sciences.
    Salmonsson, Lisa
    Örebro University, School of Humanities, Education and Social Sciences.
    Sortering av hushållsavfall: En förstudie om varför människor sorterar eller inte sorterar hushållsavfall som de gör samt om vilka insatser som kan få fler att sortera mer2019Report (Other academic)
  • Amnå, Erik
    Örebro University, School of Humanities, Education and Social Sciences.
    Nordic Education in a Democratically Troublesome time: Threats and Opportunities2019Conference proceedings (editor) (Other academic)
  • Rostami, Elham
    Örebro University, Örebro University School of Business.
    Tailoring policies and involving users in constructing security policies: A mapping study2019In: Proceeding of the Thirteen International Syposium on Human Aspect of Information Security & Assurance, 2019Conference paper (Refereed)
    Abstract [en]

    The purpose of this study is to survey existing information security policy (ISP) construction research to understand to what extent the concept of tailored ISP and user involvement have been considered by researchers. The results are based on a literature mapping study of ISP construction between 1990 and 2017 in Scopus and Web of Science databases. The findings show that researchers have not given tailoring of ISPs any attention and there are only a few researchers that paid attention to involving users in constructing ISPs. This research has implications for both researchers and practitioners and shows the way for the future researches by focusing on the concept of tailored policy and how it can be achieved as well as involving users in such tailoring.

  • Mielle, Malcolm
    Örebro University, School of Science and Technology.
    Helping robots help us: Using prior information for localization, navigation, and human-robot interaction2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Maps are often used to provide information and guide people. Emergency maps or floor plans are often displayed on walls and sketch maps can easily be drawn to give directions. However, robots typically assume that no knowledge of the environment is available before exploration even though making use of prior maps could enhance robotic mapping. For example, prior maps can be used to provide map data of places that the robot has not yet seen, to correct errors in robot maps, as well as to transfer information between map representations.

    I focus on two types of prior maps representing the walls of an indoor environment: layout maps and sketch maps. I study ways to relate information of sketch or layout maps with an equivalent metric map and study how to use layout maps to improve the robot’s mapping. Compared to metric maps such as sensor-built maps, layout and sketch maps can have local scale errors or miss elements of the environment, which makes matching and aligning such heterogeneous map types a hard problem.

    I aim to answer three research questions: how to interpret prior maps by finding meaningful features? How to find correspondences between the features of a prior map and a metric map representing the same environment? How to integrate prior maps in SLAM so that both the prior map and the map built by the robot are improved?

    The first contribution of this thesis is an algorithm that can find correspondences between regions of a hand-drawn sketch map and an equivalent metric map and achieves an overall accuracy that is within 10% of that of a human. The second contribution is a method that enables the integration of layout map data in SLAM and corrects errors both in the layout and the sensor map.

    These results provide ways to use prior maps with local scale errors and different levels of detail, whether they are close to metric maps, e.g. layout maps, or non-metric maps, e.g. sketch maps. The methods presented in this work were used in field tests with professional fire-fighters for search and rescue applications in low-visibility environments. A novel radar sensor was used to perform SLAM in smoke and, using a layout map as a prior map, users could indicate points of interest to the robot on the layout map, not only during and after exploration, but even before it took place.

    List of papers
    1. Using sketch-maps for robot navigation: interpretation and matching
    Open this publication in new window or tab >>Using sketch-maps for robot navigation: interpretation and matching
    2016 (English)In: 2016 IEEE International Symposium on Safety, Security, and Rescue Robotics (SSRR), New York: Institute of Electrical and Electronics Engineers (IEEE), 2016, p. 252-257Conference paper, Published paper (Refereed)
    Abstract [en]

    We present a study on sketch-map interpretationand sketch to robot map matching, where maps have nonuniform scale, different shapes or can be incomplete. For humans, sketch-maps are an intuitive way to communicate navigation information, which makes it interesting to use sketch-maps forhuman robot interaction; e.g., in emergency scenarios.

    To interpret the sketch-map, we propose to use a Voronoi diagram that is obtained from the distance image on which a thinning parameter is used to remove spurious branches. The diagram is extracted as a graph and an efficient error-tolerant graph matching algorithm is used to find correspondences, while keeping time and memory complexity low.

    A comparison against common algorithms for graph extraction shows that our method leads to twice as many good matches. For simple maps, our method gives 95% good matches even for heavily distorted sketches, and for a more complex real-world map, up to 58%. This paper is a first step toward using unconstrained sketch-maps in robot navigation.

    Place, publisher, year, edition, pages
    New York: Institute of Electrical and Electronics Engineers (IEEE), 2016
    Keywords
    sketch, sketch-map, human robot interface, HRI, graph matching
    National Category
    Computer Sciences
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-53826 (URN)10.1109/SSRR.2016.7784307 (DOI)000391310800039 ()2-s2.0-85009754966 (Scopus ID)978-1-5090-4349-1 (ISBN)
    Conference
    14th IEEE International Symposium on Safety, Security and Rescue Robotics (SSRR 2016), EPFL, Lausanne, Switzerland, October 23-27, 2016
    Funder
    EU, Horizon 2020, ICT-23-2014 645101 SmokeBot
    Available from: 2016-12-09 Created: 2016-12-07 Last updated: 2019-10-02Bibliographically approved
    2. A method to segment maps from different modalities using free space layout MAORIS: map of ripples segmentation
    Open this publication in new window or tab >>A method to segment maps from different modalities using free space layout MAORIS: map of ripples segmentation
    2018 (English)Conference paper, Published paper (Refereed)
    Abstract [en]

    How to divide floor plans or navigation maps into semantic representations, such as rooms and corridors, is an important research question in fields such as human-robot interaction, place categorization, or semantic mapping. While most works focus on segmenting robot built maps, those are not the only types of map a robot, or its user, can use. We present a method for segmenting maps from different modalities, focusing on robot built maps and hand-drawn sketch maps, and show better results than state of the art for both types.

    Our method segments the map by doing a convolution between the distance image of the map and a circular kernel, and grouping pixels of the same value. Segmentation is done by detecting ripple-like patterns where pixel values vary quickly, and merging neighboring regions with similar values.

    We identify a flaw in the segmentation evaluation metric used in recent works and propose a metric based on Matthews correlation coefficient (MCC). We compare our results to ground-truth segmentations of maps from a publicly available dataset, on which we obtain a better MCC than the state of the art with 0.98 compared to 0.65 for a recent Voronoi-based segmentation method and 0.70 for the DuDe segmentation method.

    We also provide a dataset of sketches of an indoor environment, with two possible sets of ground truth segmentations, on which our method obtains an MCC of 0.56 against 0.28 for the Voronoi-based segmentation method and 0.30 for DuDe.

    Place, publisher, year, edition, pages
    IEEE Computer Society, 2018
    Keywords
    map segmentation, free space, layout
    National Category
    Robotics
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-68421 (URN)10.1109/ICRA.2018.8461128 (DOI)000446394503114 ()
    Conference
    IEEE International Conference on Robotics and Automation (ICRA 2018), Brisbane, Australia, May 21-25, 2018
    Funder
    EU, Horizon 2020, ICT-23-2014 645101 SmokeBotKnowledge Foundation, 20140220
    Available from: 2018-08-09 Created: 2018-08-09 Last updated: 2019-10-10Bibliographically approved
    3. URSIM: Unique Regions for Sketch Map Interpretation and Matching
    Open this publication in new window or tab >>URSIM: Unique Regions for Sketch Map Interpretation and Matching
    2019 (English)In: Robotics, E-ISSN 2218-6581, Vol. 8, no 2, article id 43Article in journal (Refereed) Published
    Abstract [en]

    We present a method for matching sketch maps to a corresponding metric map, with the aim of later using the sketch as an intuitive interface for human-robot interactions. While sketch maps are not metrically accurate and many details, which are deemed unnecessary, are omitted, they represent the topology of the environment well and are typically accurate at key locations. Thus, for sketch map interpretation and matching, one cannot only rely on metric information. Our matching method first finds the most distinguishable, or unique, regions of two maps. The topology of the maps, the positions of the unique regions, and the size of all regions are used to build region descriptors. Finally, a sequential graph matching algorithm uses the region descriptors to find correspondences between regions of the sketch and metric maps. Our method obtained higher accuracy than both a state-of-the-art matching method for inaccurate map matching, and our previous work on the subject. The state of the art was unable to match sketch maps while our method performed only 10% worse than a human expert.

    Place, publisher, year, edition, pages
    MDPI, 2019
    Keywords
    Map matching, sketch, human-robot interaction, interface, graph matching, segmentation
    National Category
    Computer Vision and Robotics (Autonomous Systems)
    Identifiers
    urn:nbn:se:oru:diva-75741 (URN)10.3390/robotics8020043 (DOI)000475325600020 ()2-s2.0-85069975721 (Scopus ID)
    Funder
    Knowledge Foundation, 20140220
    Note

    Funding Agency:

    EU  ICT-26-2016 732737

    Available from: 2019-08-13 Created: 2019-08-13 Last updated: 2019-10-10Bibliographically approved
    4. SLAM auto-complete: completing a robot map using an emergency map
    Open this publication in new window or tab >>SLAM auto-complete: completing a robot map using an emergency map
    2017 (English)In: 2017 IEEE International Symposium on Safety, Security and Rescue Robotics (SSRR), IEEE conference proceedings, 2017, p. 35-40, article id 8088137Conference paper, Published paper (Refereed)
    Abstract [en]

    In search and rescue missions, time is an important factor; fast navigation and quickly acquiring situation awareness might be matters of life and death. Hence, the use of robots in such scenarios has been restricted by the time needed to explore and build a map. One way to speed up exploration and mapping is to reason about unknown parts of the environment using prior information. While previous research on using external priors for robot mapping mainly focused on accurate maps or aerial images, such data are not always possible to get, especially indoor. We focus on emergency maps as priors for robot mapping since they are easy to get and already extensively used by firemen in rescue missions. However, those maps can be outdated, information might be missing, and the scales of rooms are typically not consistent.

    We have developed a formulation of graph-based SLAM that incorporates information from an emergency map. The graph-SLAM is optimized using a combination of robust kernels, fusing the emergency map and the robot map into one map, even when faced with scale inaccuracies and inexact start poses.

    We typically have more than 50% of wrong correspondences in the settings studied in this paper, and the method we propose correctly handles them. Experiments in an office environment show that we can handle up to 70% of wrong correspondences and still get the expected result. The robot can navigate and explore while taking into account places it has not yet seen. We demonstrate this in a test scenario and also show that the emergency map is enhanced by adding information not represented such as closed doors or new walls.

    Place, publisher, year, edition, pages
    IEEE conference proceedings, 2017
    Keywords
    SLAM, robotics, graph, graph SLAM, emergency map, rescue, exploration, auto complete, SLAM, robotics, graph, graph SLAM, plan de secours, sauvetage, exploration, auto complete
    National Category
    Computer Vision and Robotics (Autonomous Systems)
    Research subject
    Computer Science
    Identifiers
    urn:nbn:se:oru:diva-62057 (URN)10.1109/SSRR.2017.8088137 (DOI)000426991900007 ()2-s2.0-85040221684 (Scopus ID)978-1-5386-3923-8 (ISBN)978-1-5386-3924-5 (ISBN)
    Conference
    15th IEEE International Symposium on Safety, Security and Rescue Robotics (SSRR 2017), ShanghaiTech University, China, October 11-13, 2017
    Projects
    EU H2020 project SmokeBot (ICT- 23-2014 645101)
    Funder
    Knowledge Foundation, 20140220
    Note

    Funding Agency:

    EU  ICT-23-2014645101

    Available from: 2017-11-08 Created: 2017-11-08 Last updated: 2019-10-02Bibliographically approved
    5. The Auto-Complete Graph: Merging and Mutual Correction of Sensor and Prior Maps for SLAM
    Open this publication in new window or tab >>The Auto-Complete Graph: Merging and Mutual Correction of Sensor and Prior Maps for SLAM
    2019 (English)In: Robotics, E-ISSN 2218-6581, Vol. 8, no 2, article id 40Article in journal (Refereed) Published
    Abstract [en]

    Simultaneous Localization And Mapping (SLAM) usually assumes the robot starts without knowledge of the environment. While prior information, such as emergency maps or layout maps, is often available, integration is not trivial since such maps are often out of date and have uncertainty in local scale. Integration of prior map information is further complicated by sensor noise, drift in the measurements, and incorrect scan registrations in the sensor map. We present the Auto-Complete Graph (ACG), a graph-based SLAM method merging elements of sensor and prior maps into one consistent representation. After optimizing the ACG, the sensor map's errors are corrected thanks to the prior map, while the sensor map corrects the local scale inaccuracies in the prior map. We provide three datasets with associated prior maps: two recorded in campus environments, and one from a fireman training facility. Our method handled up to 40% of noise in odometry, was robust to varying levels of details between the prior and the sensor map, and could correct local scale errors of the prior. In field tests with ACG, users indicated points of interest directly on the prior before exploration. We did not record failures in reaching them.

    Place, publisher, year, edition, pages
    MDPI, 2019
    Keywords
    SLAM, prior map, emergency map, layout map, graph-based SLAM, navigation, search and rescue
    National Category
    Computer Vision and Robotics (Autonomous Systems)
    Identifiers
    urn:nbn:se:oru:diva-75742 (URN)10.3390/robotics8020040 (DOI)000475325600017 ()2-s2.0-85069926702 (Scopus ID)
    Funder
    Knowledge Foundation, 20140220
    Note

    Funding Agency:

    EU  ICT-26-2016 732737  ICT-23-2014 645101

    Available from: 2019-08-13 Created: 2019-08-13 Last updated: 2019-10-02Bibliographically approved
    6. A comparative analysis of radar and lidar sensing for localization and mapping
    Open this publication in new window or tab >>A comparative analysis of radar and lidar sensing for localization and mapping
    2019 (English)In: 2019 European Conference on Mobile Robots (ECMR), IEEE, 2019Conference paper, Published paper (Refereed)
    Abstract [en]

    Lidars and cameras are the sensors most commonly used for Simultaneous Localization And Mapping (SLAM). However, they are not effective in certain scenarios, e.g. when fire and smoke are present in the environment. While radars are much less affected by such conditions, radar and lidar have rarely been compared in terms of the achievable SLAM accuracy. We present a principled comparison of the accuracy of a novel radar sensor against that of a Velodyne lidar, for localization and mapping.

    We evaluate the performance of both sensors by calculating the displacement in position and orientation relative to a ground-truth reference positioning system, over three experiments in an indoor lab environment. We use two different SLAM algorithms and found that the mean displacement in position when using the radar sensor was less than 0.037 m, compared to 0.011m for the lidar. We show that while producing slightly less accurate maps than a lidar, the radar can accurately perform SLAM and build a map of the environment, even including details such as corners and small walls.

    Place, publisher, year, edition, pages
    IEEE, 2019
    National Category
    Computer Vision and Robotics (Autonomous Systems)
    Identifiers
    urn:nbn:se:oru:diva-76976 (URN)
    Conference
    9th European Conference on Mobile Robots (ECMR 2019), Prague, Czech Republic, September 4-6, 2019
    Available from: 2019-10-02 Created: 2019-10-02 Last updated: 2019-12-10Bibliographically approved
  • Sugrue, Ciaran
    et al.
    University College Dublin, Ireland.
    Solbrekke, Tone Dyrdal
    University of Oslo, Oslo, Norway.
    Bergh, Andreas
    Örebro University, School of Humanities, Education and Social Sciences.
    Sutphen, Molly
    University of Oslo, Oslo, Norway.
    Fossland, Trine
    University of Tromsø, Tromsø, Norway.
    University leaders’ talk about institutional missions and academic developers’ contributions2019In: European Educational Research Journal (online), ISSN 1474-9041, E-ISSN 1474-9041, Vol. 18, no 6, p. 743-759Article in journal (Refereed)
    Abstract [en]

    There are increasing external pressures on 21st-century universities to be engines of economic recovery and growth. In this rapidly altering landscape, how university senior leaders articulate the purpose of university education and the contribution of academic developers to fulfil these education purposes is a matter of empirical interest. Senior leaders and academic developers have particular responsibilities since they impact educational quality at an institutional level. Senior leaders are responsible for orienting their institutions, giving direction to colleagues in the process, while their implicit leadership theories animate effort and interactions. Academic developers are employed to provide educational programmes for academics to develop their pedagogical competence, and are increasingly deployed by university leaders to implement new quality assurance systems. Such responsibilities strongly suggest agency and relative autonomy to forge new alliances and collaborative networks where these did not previously exist; they are simultaneously required to be leaders and followers. Consequently, the portfolios of academic developers have expanded exponentially, strategically walking a tightrope between the potentially coercive message of strategic missions and the relative autonomy of academic staff, brokering new horizons of university education in a collegial, collaborative and horizontal manner. The paper captures the dynamics of leading education in four universities: the brokering responsibilities of academic developers.

  • Sandberg, Tommy
    Örebro University, School of Humanities, Education and Social Sciences.
    The Difference Approach to Narrative Fiction: A Recurring Critique of Narratology and Its Implications for the Study of Novels and Short Stories2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The aim of this thesis is to advance the critical examination of narratology, or the study of storytelling. I analyze four versions of a critique of the dominant theory of narrative fiction in narratology and discuss this critique’s methodological implications. The critics, Sylvie Patron, Lars-Åke Skalin, Richard Walsh, and the proponents of unnatural narratology have, I suggest, similar understandings of narratology’s handling of works like novels and short stories as well as similar alternative approaches. I situate the critique among relevant theories of fiction and salient aspects of narratology, and conclude that the most radical critics have a difference approach to narrative fiction. This means treating this literary practice as following another rule system for creating meaning than other kinds of storytelling. These critics seem to base their reasoning on their readerly intuitions about how novels and short stories function; yet their approach also lends itself to, for instance, discussions on how such works afford life visions or worldviews. In contrast to this approach, I describe narratology, in the critics’ view, as having a sameness approach that treats narrative fiction as a subtype of “narrative” in the sense of the communication of events by a narrator.

    The three opening articles of the thesis comprise a metadiscussion of the critique. I here describe, in part with Greger Andersson, the critics’ ideas, characterize the critique as a whole, and speculate about why it has had no apparent effect on narratology. The two latter articles utilize the difference approach in analyses of Angela Carter’s “The Loves of Lady Purple” and Sara Stridsberg’s Drömfakulteten (The Faculty of Dreams) while discussing narratological concepts and issues. Future studies might continue this discussion or inquire further about, for example, the relations between different narrative practices or what role different intuitions about narrative fiction play in descriptions and analyses.

    List of papers
    1. The critique of the common theory of narrative fiction in narratology: Pursuing difference
    Open this publication in new window or tab >>The critique of the common theory of narrative fiction in narratology: Pursuing difference
    2019 (English)In: Frontiers of Narrative Studies, ISSN 2509-4882, Vol. 5, no 1, p. 17-34Article in journal (Other academic) Published
    Abstract [en]

    This article aims to characterize a commonly misunderstood and neglected critique of narratology and insists that the critique could advance the narratological discussions if taken more seriously. I describe the notions of three individual critics and one group of critics and their suggested alternatives to what they hold to be the dominating description of narrative fiction in narratology. In turn, I take up Sylvie Patron’s linguistic approach, Lars-Åke Skalin’s aesthetic approach, and Richard Walsh’s pragmatic approach, as well as unnatural narratology (which is less radical), and suggest that they have a Difference approach to narrative fiction. The critique is contrasted with what I refer to as a Sameness approach, guiding the dominating description of narrative fiction in narratology. The Sameness approach relates novels and short stories to a notion of a default mode of “narrative” which is based on situated speech about something that has happened. This is, according to the critics, a mistake. The main thrust of the critics, although with some exceptions, is instead that narrative fiction needs to be approached as sui generis in order to be described effectively. Yet how this should be done is still open for debate.

    Place, publisher, year, edition, pages
    Berlin: Walter de Gruyter, 2019
    Keywords
    Difference approach, Sylvie Patron, Lars-Åke Skalin, unnatural narratology, Richard Walsh
    National Category
    General Literature Studies
    Research subject
    Literature
    Identifiers
    urn:nbn:se:oru:diva-75975 (URN)10.1515/fns-2019-0003 (DOI)
    Available from: 2019-08-29 Created: 2019-08-29 Last updated: 2019-10-10Bibliographically approved
    2. Sameness versus Difference in Narratology: Two Approaches to Narrative Fiction
    Open this publication in new window or tab >>Sameness versus Difference in Narratology: Two Approaches to Narrative Fiction
    2018 (English)In: Narrative (Columbus, Ohio), ISSN 1063-3685, E-ISSN 1538-974X, Vol. 26, no 3, p. 241-261Article in journal (Refereed) Published
    Abstract [en]

    In this article we examine the critical proposition that common versions of narratology do not provide an accurate description of narrative fiction and analyze why this critique has mostly been disregarded by narratology. The theoreticians we refer to-Sylvie Patron, Richard Walsh, and Lars-Ake Skalin-do not accept the notion that narrative fiction should be understood in terms of non-fictional narratives. We label their position a "difference approach" in contrast to a putative "sameness approach." We find their "difference" arguments convincing and therefore ask why they have had no apparent effect on narratology. As we discuss misreadings that the criticized approach to narrative fiction could be expected to generate and arguments that refute the existence of such misreadings, as well as suggested readings of narrative fiction by Liesbeth Korthals Altes, James Phelan, David Herman, and Gerard Genette, we make the claim, referring to Phelan's rhetorical narratology, that sameness narratology is often presented as a theory but in fact used and defended as a method or toolbox. Our suggestion is that it would be better to rework the theory of narrative fiction commonly adopted by narratologists so that the theoretical assertions become congruent with the analytical practice and with the intuitions about narrative fiction that the analytical practice implies. We thus support the difference approach.

    Place, publisher, year, edition, pages
    Ohio State University Press, 2018
    Keywords
    Narratology, sameness, difference, narrative fiction, theory, method
    National Category
    Specific Literatures
    Identifiers
    urn:nbn:se:oru:diva-69086 (URN)10.1353/nar.2018.0012 (DOI)000444570400001 ()
    Available from: 2018-10-01 Created: 2018-10-01 Last updated: 2019-10-10Bibliographically approved
    3. A Reply to Mari Hatavara and Matti Hyvärinen
    Open this publication in new window or tab >>A Reply to Mari Hatavara and Matti Hyvärinen
    2019 (English)In: Narrative (Columbus, Ohio), ISSN 1063-3685, E-ISSN 1538-974X, Vol. 27, no 3, p. 378-381Article in journal, Editorial material (Refereed) Published
    Place, publisher, year, edition, pages
    Ohio State University Press, 2019
    National Category
    Specific Literatures
    Identifiers
    urn:nbn:se:oru:diva-76670 (URN)10.1353/nar.2019.0022 (DOI)000488204000008 ()
    Available from: 2019-09-24 Created: 2019-09-24 Last updated: 2019-10-25Bibliographically approved
    4. An Evaluation of the Voice Concept(s) in Theories of Literary Fiction: Suggestions by Patron, Walsh, and Genette
    Open this publication in new window or tab >>An Evaluation of the Voice Concept(s) in Theories of Literary Fiction: Suggestions by Patron, Walsh, and Genette
    2018 (English)In: From Narrative to Narrativity: Half a Century of Narratology / [ed] Milosavljević Milić, Snežana; Jovanović, Jelena; Bojanić Ćirković, Mirjana, Niš, Serbia: Faculty of Philosophy, University of Niš , 2018, p. 163-172Chapter in book (Refereed)
    Abstract [en]

    If we are to use narratology as a "toolbox", as some scholars propose, we must test the value of the tools. In this paper I present an understanding of voice based on literary functions in Angela Carter’s "The Loves of Lady Purple", and then I evaluate three notions of voice in narratology. First out are the critical approaches of Sylvie Patron, who wants to abandon the term "voice" completely because of its many incongruent meanings, and Richard Walsh, who pragmatically reformulates the popular Genettean definitions according to his theory of the rhetoric of fictionality. Lastly I discuss how Genette himself would tamper with Carter’s short story. While Patron may be too harsh in her conclusion, Walsh and Genette seem to be able to accommodate voice in "Lady Purple" when they talk about ideology, at least partly. On the negative side, they both miss adequate notions of style.

    Place, publisher, year, edition, pages
    Niš, Serbia: Faculty of Philosophy, University of Niš, 2018
    Keywords
    Angela Carter, discourse narratology, ideology, rhetoric of fictionality, style, voice
    National Category
    General Literature Studies
    Research subject
    Literature
    Identifiers
    urn:nbn:se:oru:diva-65798 (URN)978-86-7379-470-9 (ISBN)
    Available from: 2018-03-14 Created: 2018-03-14 Last updated: 2019-09-24Bibliographically approved
    5. A “fucked up” novel, narratology, and the Difference approach to literary fiction
    Open this publication in new window or tab >>A “fucked up” novel, narratology, and the Difference approach to literary fiction
    2017 (English)In: Frontiers of Narrative Studies, E-ISSN 2509-4890, Vol. 3, no 2, p. 256-272Article in journal (Refereed) Published
    Abstract [en]

    Drömfakulteten (2006) is an experimental novel by the Swedish writer Sara Stridsberg portraying the life of political activist and writer Valerie Solanas. I read Drömfakulteten as a “literary fantasy” where the forms, the themes, and the atmosphere are foregrounded rather than the biography of Solanas, and suggest that it can be viewed as a deliberate work of art filled with affordances for the reader. Central to my analysis is the recurring idea of “fucking up” as a way of disobeying social, political, and literary (narrative) norms. In relation to narratology, I take on the novel with a Difference approach to fiction, guided by notions from Sylvie Patron, Lars-Åke Skalin, and Richard Walsh. In this approach, fiction is seen as functioning differently in a qualitative sense compared to natural narrative. The Difference approach leads to a reading that lies close to the intuitions of reviewers and highlights the strong literary potential of the novel.

    Place, publisher, year, edition, pages
    Mouton de Gruyter, 2017
    Keywords
    Affordances, Difference approach, Drömfakulteten, literary fiction, narrativity
    National Category
    General Literature Studies
    Research subject
    Literature
    Identifiers
    urn:nbn:se:oru:diva-63380 (URN)10.1515/fns-2017-0017 (DOI)
    Available from: 2017-12-14 Created: 2017-12-14 Last updated: 2019-10-10Bibliographically approved
  • Axelsson, Tobias
    Örebro University, School of Humanities, Education and Social Sciences.
    Att tolka och praktisera jämställdhet i förskola och grundskola: Slutrapport av projektet Forskningsbaserad samverkan – med målet att förbättra jämställdhetsarbetet i Askersunds kommuns förskolor och grundskolor2019Report (Other academic)
    Abstract [sv]

    Syftet med denna rapport är att beskriva och problematisera hur jämställdhet uppfattas och hur jämställdhetsarbete bedrivs i förskola och grundskola. Rapporten har gjorts i och på uppdrag från Askersunds kommun och behandlar följande forskningsfrågor:

    1. Vilka förståelser och upplevelser av jämställdhet och ojämställdhet har elever?

    2. Hur uppfattar pedagoger sitt jämställdhetsuppdrag?

    3. Hur praktiserar pedagoger sitt jämställdhetsuppdrag?

    4. Vilka förståelser finns av jämställdhet i centrala dokument om förskola och grundskola på kommunal nivå?

    Utifrån 28 observationsdagar (i årskurs två, fem och nio), nitton intervjuer (med arbetslag i grundskola, pedagoger i förskola och grundskola samt elever i årskurs nio) och dokumentanalyser undersöks särskilt hur pedagoger tolkar och praktiserar jämställdhet. Rapportens resultat visar: 1) att elever är positivt inställda till jämställdhet och har erfarenheter av ojämställdhet, 2) att det finns stora skillnader mellan om och hur pedagoger tolkar jämställdhetsuppdraget, 3) att pedoger varierar mellan att använda sig att könsavkodade och reflexiva/synliggörande jämställdhetsstrategier, 4) att jämställdhet förstås dels som en administrativ rutinåtgärd och dels som ett problemorienterat arbete. Rapporten rekommenderar ett intersektionellt jämställdhetsarbete som pendlar mellan att betrakta utbildning som, om respektive för jämställdhet.

  • Mårdh, Andreas
    Örebro University, School of Humanities, Education and Social Sciences.
    Inquiring into the political dimension of history classroom practices: Suggestions for epistemological criteria and analytical concepts2019In: Historical Encounters: A journal of historical consciousness, historical cultures and history education, E-ISSN 2203-7543, Vol. 6, no 1, p. 15-28Article in journal (Refereed)
    Abstract [en]

    In this paper, three epistemological criteria are suggested against which analytical frameworks for studying the political dimension of history classroom practices can be deemed viable. The suggested criteria - (I) the primacy of practice, (II) the primacy of empirical openness and (III) the primacy of the political - are articulated by conducting critical and affirmative readings of previously established concepts, primarily historical consciousness. To clarify their application, the criteria are positioned in relation to the premises and concepts of a potential framework; namely, the logics of critical explanation (Glynos & Howarth, 2007), the viability of which is argued for theoretically and empirically.

  • González-Calvo, Gustavo
    et al.
    Department of Musical, Plastic and Body Expression, University of Valladolid, Palencia, Spain.
    Varea, Valeria
    Örebro University, School of Health Sciences.
    A Turning Point as an Opportunity to (Re)Think and Give a Voice to One’s Own Body2019In: Societies, E-ISSN 2075-4698, Vol. 9, no 3, article id 60Article in journal (Refereed)
    Abstract [en]

    This article explores the intersectionalities of masculinity, fatherhood, and physical activity in relation to a Physical Education teacher who has been diagnosed with an illness. In so doing, we draw on autobiographical narratives to delve into how embodied subjectivities are constructed to advance knowledge on a new embodied way of being a man and a PE teacher that can be accepted and embraced. The results are organised into three main themes: (1) narratives of continuation: the “before” of chronic illness; (2) narratives of disruption: back pain and temporary physical disability; and (3) restitution narratives: damn it, now that I am a father. The results suggest that narratives such as those presented in this article contribute to the continuously changing process of life projects and that illness can assist in redefining and reconstituting the persona of a PE teacher.

  • Flygare, Ann-Marie
    et al.
    Örebro University, Örebro University School of Business.
    Hedlin, Dan
    Department of Statistics, Stockholm University, Stockholm, Sweden.
    Empirical Study on the Size of Nonresponse Bias2018In: JSM Proceedings, Survey Research Methods Section, Alexandria, VA, 2018Conference paper (Other academic)
    Abstract [en]

    There are expressions for nonresponse bias, all of which require population quantities. In one expression for nonresponse bias, due to Bethlehem (1988, 2009), the bias is approximately equal to a function of the population covariance between the study variable and the response propensity (probability) and the population mean of the propensities. The covariance is hard to estimate (due to nonresponse). To empirically examine the covariance and the nonresponse bias, we have done two studies where the sample values of survey variables are known and the response propensities are estimated.The first study is a mail survey of a population of residents in the city of Solna in Sweden,20-74 years of age. The questionnaire consists of items on marital status and income; we have obtained the true values of those from the Swedish Tax Agency. We also know birth country, the type of area of residents, specific age and gender of each sampled individual.The second study is a web survey at Stockholm University, the population is faculty employees at the department of psychology. This survey is a census and the variables that we regard as our study variables are income from university and total income. The true values of income from university are given by the HR-department and total income from the Tax Agency.

  • Hemberg, Jessica
    et al.
    Åbo Akademi University, Åbo, Finland.
    Bergdahl, Elisabeth
    Örebro University, School of Health Sciences.
    Ethical sensitivity and perceptivness in palliative home care through co-creation2019In: Nursing Ethics, ISSN 0969-7330, E-ISSN 1477-0989Article in journal (Refereed)
    Abstract [en]

    Background: In research on co-creation in nursing, a caring manner can be used to create opportunities whereby the patient’s quality of life can be increased in palliative home care. This can be described as an ethical cornerstone and the goal of palliative care. To promote quality of life, nurses must be sensitive to patients’ and their relatives’ needs in care encounters. Co-creation can be defined as the joint creation of vital goals for patients through the process of shared knowledge between nurses, patients and their relatives.

    Aim: The aim of this study was to explore nurses’ experiences of caring encounters and co-creation in palliative home care from an ethical perspective.

    Research design, participants, and research context: A hermeneutical approach was used. The material consisted of texts from interviews with 12 nurses in a home care context. The method was inspired by thematic analysis.

    Ethical considerations: Informed consent was sought from the participants regarding study participation and the storage and handling of data for research purposes.

    Findings: An overall theme, a main theme and four sub-themes emerged. Through ethical sensitivity and perceptivity, nurses can balance their actions in the moment and change their nursing care actions accordingto the patient’s wishes through co-creation in encounters. Here the time is crucial, as the time needed is unique to each patient.

    Discussion: The themes together can be considered prerequisites for good palliative home care. If nurses fail to be sensitive and perceptive in encounters with dying patients, good palliative home care cannot be achieved. Ethical sensitivity and perceptiveness can also be considered a part of nurses’ ethical competence.

    Conclusion: Patients’ dignity can be preserved through ethical sensitivity and perceptiveness, which is fundamental for good palliative care. Co-creation from patients’ perspectives should be the focus of future research.

  • Mansouri, Masoumeh
    et al.
    Örebro University, School of Science and Technology.
    Lacerda, Bruno
    Oxford Robotics Institute, University of Oxford, UK.
    Hawes, Nick
    Oxford Robotics Institute, University of Oxford, UK.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Multi-Robot Planning Under Uncertain Travel Times and Safety Constraints2019In: Proceedings of the Twenty-Eighth International Joint Conference on Artificial Intelligence (IJCAI-19), 2019, p. 478-484Conference paper (Refereed)
    Abstract [en]

    We present a novel modelling and planning approach for multi-robot systems under uncertain travel times. The approach uses generalised stochastic Petri nets (GSPNs) to model desired team behaviour, and allows to specify safety constraints and rewards. The GSPN is interpreted as a Markov decision process (MDP) for which we can generate policies that optimise the requirements. This representation is more compact than the equivalent multi-agent MDP, allowing us to scale better. Furthermore, it naturally allows for asynchronous execution of the generated policies across the robots, yielding smoother team behaviour. We also describe how the integration of the GSPN with a lower-level team controller allows for accurate expectations on team performance. We evaluate our approach on an industrial scenario, showing that it outperforms hand-crafted policies used in current practice.

  • Stenlund, Jörgen
    Örebro University, School of Science and Technology. Institutionen för teknik och naturvetenskap, Linköpings universitet, Linköping, Sweden.
    Travelling through time: Students’ interpretation of evolutionary time in dynamic visualizations2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Evolutionary knowledge is important to understand and address contemporary challenges such as loss of biodiversity, climate change and antibiotic resistance. An important aspect that is considered to be a threshold concept in teaching and learning about evolution is the time it involves. The history of evolution comprises several scales of magnitude, some of which are far from direct human experience and therefore difficult to understand. One way of addressing this issue is to use dynamic visualizations that represent time, for example, to facilitate teaching and learning about evolution.

    This thesis investigates how students’ comprehension of evolution and evolutionary time can be facilitated by visualizations in educational settings. Two different dynamic visualizations were investigated. In paper I different temporal versions of a spatio-temporal animation depicting hominin evolution were explored. The temporal information was expressed as one or several timelines along which an animated cursor moved, indicating the rate of time. Two variables, the number of timelines with different scales, and the mode of the default animated time rate (either constant throughout the animation or decreasing as the animation progressed), were combined to give four different time representations. The temporal aspects investigated were undergraduate students' ability to find events at specific times, comprehend order, comprehend concurrent events, comprehend the length of time intervals, and their ability to compare the lengths of time intervals.

    In paper II, perceptions and comprehension of temporal aspects in an interactive, multi-touch tabletop application, DeepTree, were investigated. This application depicts the tree of life. The focus was on the interactive aspects, especially how the zooming feature was perceived, but also on any misinterpretations associated with the interaction. The same temporal aspects listed for paper I were also implicitly investigated.

    The findings indicate that handling the problem of large differences in scale by altering the rate of time in the visualization can facilitate perception of certain temporal aspects while, at the same time, can hinder a correct comprehension of other temporal aspects. Findings concerning DeepTree indicate that the level of interactions varies among users, and that the zooming feature is perceived in two ways, either as a movement in time or as a movement in the metaphorical tree. Several misinterpretations were observed, for example the assumption that the zooming time in the tree corresponds to real time, that there is an implicit coherent timeline along the y-axis of the tree, and that more nodes along a branch corresponds to a longer time.

    The research reported in this thesis supports the claim that careful choice, and informed use of visualizations matters, and that different visualizations are best suited for different educational purposes

  • Lindblad, Katarina
    et al.
    Örebro University, School of Music, Theatre and Art.
    de Boise, Sam
    Örebro University, School of Music, Theatre and Art.
    Musical engagement and subjective wellbeing amongst men in the third age2020In: Nordisk tidskrift for musikkterapi - Nordic Journal of Music Therapy, ISSN 0803-9828, Vol. 29, no 1, p. 20-38Article in journal (Refereed)
    Abstract [en]

    Introduction: This article explores the wellbeing benefits of musical engagement for men in the third age. Older men face specific health challenges such as loneliness, isolation and a heightened risk for suicide, tied to gendered norms around emotional control, and a reluctance to seek professional help. There is substantial evidence of the positive health and wellbeing outcomes from older people’s engagement in music, but no studies on older men, music and wellbeing.

    Methods: Semi-structured interviews were conducted with 15 Swedish men aged 66–76, with different demographic backgrounds and engagement with music. Interviews were analysed using qualitative thematic analysis.

    Results: Analysis resulted in four themes: “emotions and embodiment”, “adjusting to growing older”, “developing and maintaining friendships” and “maintaining contact as a caregiver”. Regardless of musical genre or whether singing, playing, dancing or listening to music, the men used music to come into contact with their bodies and emotions, as well as improving relationships and social contacts. In particular, men as caregivers to sick partners benefited from sharing music with their partner, thus improving the quality of the relationship.

    Discussion: This study shows that engagement with music fills deep psychological and social/emotional needs for the participants, in both “being” with the music and “doing” musical activities, where also talking about music is highlighted as an important part of the musical engagement. The results have implications for the field of music therapy, in that it foregrounds music therapists’ potentially important role in developing opportunities for older men to engage with music.

  • Volgsten, Ulrik
    et al.
    Örebro University, School of Music, Theatre and Art.
    Pontara, Tobias
    Musikalisering och medialisering2019In: Musikens medialisering och musikaliseringen av medier och vardagsliv i Sverige / [ed] Ulrik Volgsten, Lund: Mediehistoria, Lunds universitet , 2019, p. 263-283Chapter in book (Refereed)
    Abstract [sv]

    I detta kapitel undersöks det fenomen som vi valt att kalla musikalisering. Som en ständigt ökande närvaro av musik i kultur och vardagsliv innefattar musikaliseringen både en diskursivoch en dramaturgiskdimension. Med musikens diskursiva dimension avser vi medierepresentationer och medierade diskurser ”om” musik och musikrelaterade frågor. När musik framförs åtföljs den så gott som alltid av kommentarer, personliga reflektioner, recensioner, åsikter, analyser, tolkningar, förklaringar, kontextualiseringar och mer eller mindre metaforiska beskrivningar. På samma sätt – i visuellt baserade medier som film, tv och internet – åtföljs musik av fotografiska bilder, målningar eller andra visuella gestaltningar, för att inte tala om film och rörliga bilder. Således är det inte bara "själva musiken" (dess klingande dimension, om än en sådan knappast kan särskiljas annat än analytiskt) som avses, utan också dess verbala och visuella bestämningar, vilka utgör icke-reducerbara aspekter av det vi kallar musik.

    Med musikens dramaturgiska dimension avses (till skillnad från dess diskursiva dimension) ett ökande inflytande av vad som bäst kan beskrivas som ett slags musikaliskt soundtracking av kultur och vardagsliv. Det är en process som är oupplösligt kopplad till musikens ökande närvaro i olika slags medierade berättelser, fiktiva såväl som icke-fiktiva – från fictionfilmer till dataspel, dokumentärer, nyhetssändningar, barnprogram, naturprogram, tv-sportevenemang, politiska tal på internet, hemsidor och annonser – en process där tillvaron blir alltmer strukturerad och organiserad i enlighet med en musikaliskt medierad medvetenhet. Resultatet är en tillvaro där musik inte bara ingår som en naturlig komponent utan också bidrar med att strukturera och organisera uppfattningar om, erfarenheter av och förväntningar på den levda verkligheten.

  • Pontara, Tobias
    et al.
    Volgsten, Ulrik
    Örebro University, School of Music, Theatre and Art.
    Allmänna teknologier och privata rum: förutsättningar för den digitala tidsålderns  solipsistiska ljudkultur2019In: Musikens medialisering och musikaliseringen av medier och vardagsliv i Sverige, Lund: Mediehistoria, Lunds universitet , 2019, p. 187-205Chapter in book (Refereed)
    Abstract [sv]

    Att lyssna på musik i avskildhet, solitärt lyssnande, är en av de mest utbredda formerna av musiklyssnande i vår digitala tidsålder. Men i nästan ett halvt sekel av ljudåtergivningstekniken var olika former av socialt lyssnande normen. I den här artikeln diskuterar vi vad vi ser som de viktigaste förutsättningarna för solitärt lyssnande som det utvecklades under det tjugonde århundradet. Mer specifikt argumenterar vi för att solitärt lyssnande blev den dominerande formen att lyssna vid mitten av seklet som ett resultat av tre olika men sammanhängande faktorer i det moderna samhället: (1) uppkomsten av det moderna vardagsrummet; (2) ankomsten av nya och alltmer sofistikerade teknologier för ljudåtergivning och (3) en ständigt växande individualism i samhället som helhet, vilken främjade en estetisk individualism där solitärt lyssnande fann en naturlig plats. Med internet, digital teknik och moderna ljudavskiljande hörlurar har utvecklingen lett till vad som kan beskrivas som en solipsistisk ljudkultur. Men samtidigt, genom att t.ex. dela musik och musikaliska spellistor på sociala medier, verkar äldre tiders sociala aspekter av musikaliskt lyssnande åter ha kommit till heders.

  • Volgsten, Ulrik
    Örebro University, School of Music, Theatre and Art.
    Vardagslivets fonografi: Grammofonspelande i Sverige 1903–19452019In: Musikens medialisering och musikaliseringen av medier och vardagsliv i Sverige mediehistoriskt arkiv / [ed] Ulrik Volgsten, Lund: Mediehistoria, Lunds universitet , 2019, p. 25-55Chapter in book (Refereed)
    Abstract [sv]

    Kapitlet handlar om användningen av fonografer och grammofoner under första hälften av 1900-talet. I stället för att fokusera på Storbritannien eller USA, som tidigare forskning ofta har gjort, ligger fokus på det i förhållandevis perifera Sverige. Mer specifikt är frågan hur fonografi förvandlades från att betraktas som vetenskaplig kuriosa till att bli en vardaglig medieteknologi och hur den påverkat kultur och musikalisk kommunikation. Källmaterialet består av dags- och veckotidningar, musiktidskrifter, kataloger över tidiga bostads- och hemutställningar, samt ett etnografiskt frågeformulär från 1962 med nationell räckvidd som ber om personliga minnen av grammofonen från åren runt sekelskiftet 1900. Kommersiell reklam (som utgör källmaterial för en stor del av tidigare forskning) kompletteras därmed och jämförs med andra typer av journalistiskt, vetenskapligt och populärvetenskapligt innehåll, från nyheter till korta romaner och offentliga policyplaner, till personliga minnen. Genom att undersöka medier som riktar sig till icke-specialister och amatörlyssnare (och som det visar sig, även icke-lyssnare), samt med inriktning på vardagsrummet i hemmets privatsfär, balanseras det vardagliga och prosaiska mot det åtrådda och prestigefyllda - ett brett spektrum inom vilket vardagslivet utspelade sig för en stor del av befolkningen. Resultatet av undersökningen visar två distinkta sätt att förhålla sig till inspelad musik, som beskrivs som utilitaristisktrespektive solipsistiskt.

  • Volgsten, Ulrik
    Örebro University, School of Music, Theatre and Art.
    Inledning: Medialisering och musikalisering i Sverige2019In: Musikens medialisering och musikaliseringen av medier och vardagsliv i Sverige / [ed] Ulrik Volgsten, Lund: Mediehistoria, Lunds universitet , 2019, 1, p. 5-21Chapter in book (Refereed)
    Abstract [sv]

    Musiken har genomgått en medialisering utan like de senaste hundra åren. Elektrifiering och digitalisering av musikmedierna har inneburit att musik kan höras så gott som överallt och när som helst. Vid sidan av medialisering introducerar föreliggande antologi begreppet musikalisering. Medan medialisering handlar om mediernas långsiktiga påverkan på vardagspraktiker och kommunikation, handlar musikalisering om förändringar i musikens roll. Förutom att vara en naturlig komponent i allt fler vardagssammanhang bidrar musik i allt högre grad till att strukturera och organisera uppfattningar om, erfarenheter av och förväntningar på den levda verkligheten.

  • Volgsten, Ulrik
    Örebro University, School of Music, Theatre and Art.
    Fantasy control: Implications for distributed imagination and affect attunement in music and sound2019In: The Oxford Handbook of Sound and Imagination, Volume 1 / [ed] Mark Grimshaw-Aagaard, Mads Walther-Hansen & Martin Knakkergaard, Oxford: Oxford University Press, 2019, 1, p. 229-249Chapter in book (Refereed)
    Abstract [en]

    This chapter deals with the control of imagination. Three thematically distinct aspects of sonic imagination are investigated – archive, context, and identification – together with two modes of connection with the environment – metaphorical projection and affect attunement. It is argued that much of the available work on sonic imagination, music perception, and embodied cognitive science suffers from a one-person perspective, unable to explain either the difference between environmental sound and culture-specific music, or the dominant role of feelings in our musical experiences. In its stead an approach is suggested that assigns central importance to affect attunement in our encounters with sound and music. Through a case study, different types of sonic control are exemplified, showing that control of sonic imagination may be both negative and positive for the listener.

  • Volgsten, Ulrik
    Örebro University, School of Music, Theatre and Art.
    A technology and its vicissitudes: playing the gramophone in Sweden 1903–19452019In: Popular Music, ISSN 0261-1430, E-ISSN 1474-0095, Vol. 38, no 2, p. 219-236Article in journal (Refereed)
    Abstract [en]

    This inquiry deals with the changing role of the technology and the use of phonographs and gramophones during the first half of the 20th century. Rather than looking at the UK or USA, which much previous research has done, the focus is on peripheral Sweden. More specifically the question is how phonography turned from being a scientific curiosity into becoming an everyday media technology, and how it thereby influenced culture and everyday musical communication. The findings show two distinct approaches to recorded music, which intermingle in today’s unprecedented musicalisation of culture and everyday life around the globe – approaches respectively described as utilitarian and solipsistic.

  • Gerdin, Jonas
    et al.
    Örebro University, Örebro University School of Business.
    Englund, Hans
    Örebro University, Örebro University School of Business.
    Contesting commensuration: Public response tactics to performance evaluation of academia2019In: Accounting, Auditing & Accountability Journal, ISSN 1368-0668, E-ISSN 1758-4205, Vol. 32, no 4, p. 1098-1116Article in journal (Refereed)
    Abstract [en]

    Purpose: The purpose of this paper is to explore how actors subjected to public performance evaluations may “contest commensuration,” i.e. may seek to influence how such ratings and rankings will be construed among important stakeholders.

    Design/methodology/approach: A qualitative study of press releases, and interviews with department heads, is used as a basis for the analysis.

    Findings: The empirically derived taxonomy of public responses to a state-initiated performance evaluation of educational programs shows that actors may mobilize an array of commensuration management tactics so as to maintain or improve one’s relative positional status. Such tactics may have at least three different foci, namely, on the comparison object (i.e. on the new grouping of actors), the comparison dimension (i.e. the standardized format for comparison) and the comparison rate (i.e. the rate received), respectively. The authors also find that not only are threats to positional status likely to spur commensuration management tactics, but also the opportunity to exploit a good rate.

    Originality/value: The paper augments recent research that has problematized the so-called “reactive conformance thesis” by focusing on how evaluated organizations may directly try to influence external stakeholders through public responses. The study is also one of the first that analytically disentangles how they may skillfully exploit different forms of “plasticity” that are inherent in any type of commensuration.

  • Hasche, Nina
    et al.
    Örebro University, Örebro University School of Business.
    Höglund, Linda
    School of Business, Society and Engineering (EST), Mälardalens University, Västerås, Sweden.
    Linton, Gabriel
    Örebro University, Örebro University School of Business.
    Quadruple helix as a network of relationships: creating value within a Swedish regional innovation system2019In: Journal of Small Business and Entrepreneurship, ISSN 0827-6331, E-ISSN 2169-2610Article in journal (Refereed)
    Abstract [en]

    A regional smart specialization initiative is investigated from a quadruple helix framework (industry, government, academia, and users/civil society). Based on a qualitative case study, we examine the interdependencies of actors, resources, and activities from a micro perspective. The aim is to understand the relationships and the value created between the different actors. From the results we conclude that the fourth helix should be viewed as a whole – an arena where triple helix actors in different value adding relationships take on different roles – where they create value to civil society, for example, new jobs or products for improved elderly care. In line with this, we state that the fourth helix is far more complex than limiting it to simply become a fourth separate helix of users or civil society. There is a complexity in that the fourth helix consists of both different users (including triple helix actors) as well as civil society. Users in the quadruple helix framework can also be defined in several ways depending on the context of the arena (the fourth helix) and what value adding activities they bring to civil society. Thus, users can be businesses, organizations, citizens, society, and many more things.

  • Kristoffersson, Eleonor
    Örebro University, School of Law, Psychology and Social Work.
    How to Tax The Sharing Economy2019In: Proceedings of the GSRD INTERNATIONAL CONFERENCE, World research library , 2019, p. 30-35Conference paper (Refereed)
    Abstract [en]

    The sharing economy refers to online market places that bring sellers and buyers of goods and services together. The sharing economy is rarely taxed, rarely reported to and rarely controlled by the Tax Authorities. In this paper two main problems concerning taxing the sharing economy are identified. Firstly, the sharing economy is difficult to control, since there are many small providers. Secondly, different tax treatment for businesses and private individuals makes it difficult for small providers to know how to comply with tax obligations. The solution is not the introduction of a digital services tax (DST) imposed on the intermediary platforms. Such a tax can contribute to tax the sharing economy, but not replace income tax or VAT/GST.Income tax and VAT/GST systems throughout the world are based on a scenario of businesspeople versus private individuals dating from the 20th century, which is now out of date. A solution could be to tax business persons and private individuals in a uniform way, which would provide a simpler tax system that would be easier to comply with.

  • Dmytryshyn, Andrii
    Department of Computing Science, Umeå University, Umeå, Sweden.
    Tools for Structured Matrix Computations: Stratifications and Coupled Sylvester Equations2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Developing theory, algorithms, and software tools for analyzing matrix pencils whose matrices have various structures are contemporary research problems. Such matrices are often coming from discretizations of systems of differential-algebraic equations. Therefore preserving the structures in the simulations as well as during the analyses of the mathematical models typically means respecting their physical meanings and may be crucial for the applications. This leads to a fast development of structure-preserving methods in numerical linear algebra along with a growing demand for new theories and tools for the analysis of structured matrix pencils, and in particular, an exploration of their behaviour under perturbations. In many cases, the dynamics and characteristics of the underlying physical system are defined by the canonical structure information, i.e. eigenvalues, their multiplicities and Jordan blocks, as well as left and right minimal indices of the associated matrix pencil. Computing canonical structure information is, nevertheless, an ill-posed problem in the sense that small perturbations in the matrices may drastically change the computed information. One approach to investigate such problems is to use the stratification theory for structured matrix pencils. The development of the theory includes constructing stratification (closure hierarchy) graphs of orbits (and bundles) that provide qualitative information for a deeper understanding of how the characteristics of underlying physical systems can change under small perturbations. In turn, for a given system the stratification graphs provide the possibility to identify more degenerate and more generic nearby systems that may lead to a better system design.

    We develop the stratification theory for Fiedler linearizations of general matrix polynomials, skew-symmetric matrix pencils and matrix polynomial linearizations, and system pencils associated with generalized state-space systems. The novel contributions also include theory and software for computing codimensions, various versal deformations, properties of matrix pencils and matrix polynomials, and general solutions of matrix equations. In particular, the need of solving matrix equations motivated the investigation of the existence of a solution, advancing into a general result on consistency of systems of coupled Sylvester-type matrix equations and blockdiagonalizations of the associated matrices.

  • Dmytryshyn, Andrii
    Örebro University, School of Science and Technology. Department of Computing Science, Umeå University, Umeå, Sweden.
    Skew-symmetric matrix pencils: stratification theory and tools2014Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Investigating the properties, explaining, and predicting the behaviour of a physical system described by a system (matrix) pencil often require the understanding of how canonical structure information of the system pencil may change, e.g., how eigenvalues coalesce or split apart, due to perturbations in the matrix pencil elements. Often these system pencils have different block-partitioning and / or symmetries. We study changes of the congruence canonical form of a complex skew-symmetric matrix pencil under small perturbations. The problem of computing the congruence canonical form is known to be ill-posed: both the canonical form and the reduction transformation depend discontinuously on the entries of a pencil. Thus it is important to know the canonical forms of all such pencils that are close to the investigated pencil. One way to investigate this problem is to construct the stratification of orbits and bundles of the pencils. To be precise, for any problem dimension we construct the closure hierarchy graph for congruence orbits or bundles. Each node (vertex) of the graph represents an orbit (or a bundle) and each edge represents the cover/closure relation. Such a relation means that there is a path from one node to another node if and only if a skew-symmetric matrix pencil corresponding to the first node can be transformed by an arbitrarily small perturbation to a skew-symmetric matrix pencil corresponding to the second node. From the graph it is straightforward to identify more degenerate and more generic nearby canonical structures. A necessary (but not sufficient) condition for one orbit being in the closure of another is that the first orbit has larger codimension than the second one. Therefore we compute the codimensions of the congruence orbits (or bundles). It is done via the solutions of an associated homogeneous system of matrix equations. The complete stratification is done by proving the relation between equivalence and congruence for the skew-symmetric matrix pencils. This relation allows us to use the known result about the stratifications of general matrix pencils (under strict equivalence) in order to stratify skew-symmetric matrix pencils under congruence. Matlab functions to work with skew-symmetric matrix pencils and a number of other types of symmetries for matrices and matrix pencils are developed and included in the Matrix Canonical Structure (MCS) Toolbox.

  • Broch Ålvik, Jon Mikkel
    Örebro University, School of Music, Theatre and Art.
    Touching from A Distance: Imagining Marit Larsen in Queer Spaces2019In: Radical Musicology, ISSN 1751-7788, E-ISSN 1751-7788, Vol. 7Article in journal (Refereed)
    Abstract [en]

    This article investigates into how Norwegian pop artist Marit Larsen's music and persona may be open to queer readings. Via close readings of songs and media appearances, I wish to show the possibility of meanings in the work of an artist whose music, on a superficial level, comes across as contingent on the artist’s own, heteronormative version of events.

  • Broch Ålvik, Jon Mikkel
    Örebro University, School of Music, Theatre and Art.
    Made in Sweden: Studies in popular music2019In: Svensk tidskrift för musikforskning, ISSN 0081-9816Article, book review (Refereed)
  • Svensson, Robert
    Örebro University, School of Health Sciences.
    From tracksuit to trench coat: The changing position of the Swedish male elite soccer coach between the 1960s and the 2010s2019Conference paper (Other academic)
  • Svensson, Robert
    Örebro University, School of Health Sciences.
    A valuable contribution to the growing research field of sports coaching history2019In: Idrottsforum.org/Nordic sport science forum, ISSN 1652-7224Article, book review (Other academic)
  • Susha, Iryna
    et al.
    Örebro University, Örebro University School of Business. Faculty of Technology, Policy and Management, Delft University of Technology, Delft, The Netherlands.
    Rukanova, Boriana
    Faculty of Technology, Policy and Management, Delft University of Technology, Delft, The Netherlands.
    Gil-Garcia, J. Ramon
    University at Albany, State University of New York, USA & Universidad de las Americas Puebla, Mexico.
    Tan, Yao-Hua
    Faculty of Technology, Policy and Management, Delft University of Technology, Delft, The Netherlands.
    Gasco, Mila
    University at Albany, State University of New York, USA & Universidad de las Americas Puebla, Mexico.
    Identifying mechanisms for achieving voluntary data sharing in cross-sector partnerships for public good2019In: Proceedings of the 20th Annual International Conference on Digital Government Research, ACM Digital Library, 2019, p. 227-236Conference paper (Refereed)
    Abstract [en]

    It has been advocated that sharing business data can generate public value. Still this information sharing often needs to be done on voluntary basis and that often poses major challenges. The main research question addressed in this paper is: How is voluntary information sharing to create publicvalue achieved and what are the drivers and mechanisms to achieve that? While voluntary information sharing to achieve public value is recognized in the eGovernment literature, this literature is limited to understand how such information sharing can be achieved. To address the research question, we borrow a framework of platforms for cross sector social partnerships from organization studies and use it as a conceptual lens to structure the analysis of three case studies where voluntary information sharingwas achieved in different domains. Building on the framework and our case analysis, we distinguish three types of information sharing collaborations, namely Resource-dependence platform, Social Issue platform, and Societal Sector platform which allow to distinguish the motivations why parties enter into voluntary information sharing collaborations. Our analysis suggests that while the higher goal of the voluntary information sharing may be the same (i.e. to create public value), parties are driven by different motivations of why they enter into the information sharing collaborations. Furthermore, in each of these different types of collaborations the mechanisms of how the information sharing was achieved, as well as the role the government can play, differ.

  • Quennerstedt, Mikael
    Örebro University, School of Health Sciences.
    Physical education and the art of teaching: transformative learning and teaching in physical education and sports pedagogy2019In: Sport, Education and Society, ISSN 1357-3322, E-ISSN 1470-1243, Vol. 24, no 6, p. 611-623Article in journal (Refereed)
    Abstract [en]

    The paper is the Jose Maria Cagigal Scholar Lecture presented at the AIESEP World Congress in Edinburgh 2018. In the paper I argue that the only real sustainable aim for physical education is more physical education, where different ways of being in the world as some-body are both possible and encouraged. To reach this aim, a focus on the art of teaching is vital as a way of critically scrutinising and designing transformative and genuinely pluralistic physical education practices. In order to do this I discuss education as being educative, a certain view of the child as well as teaching as a continuous act of making judgements about the why(s), what(s) and how(s) of education, normative judgements about desirable change. The take home messages involves: (i) reclaiming a certain view of the child in education, (ii) reclaiming the open-endedness of physical education, and (iii) reclaiming the art of teaching in physical education, which is about being educative and making judgements about what to bring to the educational situation. We then must start with the purpose of education - the why - before deciding on the what and how.

  • Mårdh, Andreas
    Örebro University, School of Humanities, Education and Social Sciences.
    Om historieämnets politiska dimension: diskursiva logiker i didaktisk praktik2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Today, history education is often a contested issue over which political frontiers are drawn between adversaries advocating fundamentally different visions of what constitutes a desirable curriculum and, by extension, a desirable society. At present, this dimension is in need of increased attention, considering that populist rhetoric has gained a foothold in mainstream politics and that history, as a school subject, continues to serve the purpose of constituting “the people”, often in national and ethnic terms. Against this background, the aim of this thesis is to comprehensively grasp the political dimension of history education by conducting methodological, empirical and theoretical investigations.

    The thesis draws on the pragmatist philosophy of democratic education as well as on post-structuralist theories of history, antagonism and populism. Methodologically, the thesis make use of the logics of critical explanation framework (LCE) to empirically explore how history classroom practices as well as contemporary right-wing populist discourse operate.

    The results show that the LCE methodology constitutes a viable analytical vocabulary for generating knowledge of the political dimension of history education. Furthermore, the thesis offers empirical knowledge about how and why practices of history education are interchangeably politicised and rendered stable by teachers, students and members of the public. Theoretically, populism, as a discursive logic, is criticised and then reconceptualised into an educative mode by which history teaching practices can be enacted. Collectively, the results provide a comprehensive understanding of the political dimension of history education.

    List of papers
    1. Inquiring into the political dimension of history classroom practices: Suggestions for epistemological criteria and analytical concepts
    Open this publication in new window or tab >>Inquiring into the political dimension of history classroom practices: Suggestions for epistemological criteria and analytical concepts
    2019 (English)In: Historical Encounters: A journal of historical consciousness, historical cultures and history education, E-ISSN 2203-7543, Vol. 6, no 1, p. 15-28Article in journal (Refereed) Published
    Abstract [en]

    In this paper, three epistemological criteria are suggested against which analytical frameworks for studying the political dimension of history classroom practices can be deemed viable. The suggested criteria - (I) the primacy of practice, (II) the primacy of empirical openness and (III) the primacy of the political - are articulated by conducting critical and affirmative readings of previously established concepts, primarily historical consciousness. To clarify their application, the criteria are positioned in relation to the premises and concepts of a potential framework; namely, the logics of critical explanation (Glynos & Howarth, 2007), the viability of which is argued for theoretically and empirically.

    Place, publisher, year, edition, pages
    HERMES History Education Research Network, School of Education, The University of Newcastle, 2019
    Keywords
    History Education, History Wars, Politics, Classroom Practice
    National Category
    Didactics Pedagogy History
    Research subject
    Education; History
    Identifiers
    urn:nbn:se:oru:diva-75848 (URN)000481624600002 ()
    Available from: 2019-08-21 Created: 2019-08-21 Last updated: 2019-11-15Bibliographically approved
    2. Between stability and contingency: A case study of the social, political and fantasmatic logics of Swedish history classroom practice
    Open this publication in new window or tab >>Between stability and contingency: A case study of the social, political and fantasmatic logics of Swedish history classroom practice
    2019 (English)In: Nordidactica: Journal of Humanities and Social Science Education, ISSN 2000-9879, no 1, p. 132-155Article in journal (Refereed) Published
    Abstract [en]

    This study explores the political and ideological workings of history classroom practices enacted in the context of Swedish upper secondary education. Using the post-structuralist logics of critical explanation framework (Glynos & Howarth, 2007), the paper reports on a series of video-recorded observations and outlines the discursive logics found to constitute the studied practices. At the heart of the analysis are the socially shared assumptions, political relationships of us-and-them, and ideological narratives that alternately furnish the history classroom practices with stability and contingency. The results encompass three case-specific logics: (I) a social logic demonstrating that the stability of the studied classroom practices rests on shared assumptions about historical idealism and partial progress, (II) a political logic indicating that the classroom practices are unsettled when students establish temporal equivalence between past and present us-and-them relationships, and (III) a fantasmatic logic showing that teachers and students become ideologically invested in said practices through narratives emphasizing the need to prevent the repetition of past injustices.

    Place, publisher, year, edition, pages
    Karlstad: Karlstads universitet, 2019
    Keywords
    HISTORY DIDACTICS, CLASSROOM PRACTICE, POLITICAL DIMENSION, LOGICS
    National Category
    Didactics
    Research subject
    History; Education
    Identifiers
    urn:nbn:se:oru:diva-73988 (URN)
    Available from: 2019-05-02 Created: 2019-05-02 Last updated: 2019-09-18Bibliographically approved
    3. Right-wing populism and history education: Some insights from a Swedish case study
    Open this publication in new window or tab >>Right-wing populism and history education: Some insights from a Swedish case study
    (English)Manuscript (preprint) (Other academic)
    National Category
    Pedagogy
    Identifiers
    urn:nbn:se:oru:diva-76498 (URN)
    Available from: 2019-09-18 Created: 2019-09-18 Last updated: 2019-09-18Bibliographically approved
    4. Democratic Education in the Mode of Populism
    Open this publication in new window or tab >>Democratic Education in the Mode of Populism
    2017 (English)In: Studies in Philosophy and Education, ISSN 0039-3746, E-ISSN 1573-191X, Vol. 36, no 6, p. 601-613Article in journal (Refereed) Published
    Abstract [en]

    This paper seeks to bring John Dewey’s pragmatist philosophy of democratic education and the public into dialogue with Ernesto Laclau’s theory of populism. Recognizing populism as an integral aspect of democracy, rather than as its antithesis, the purpose of this paper is to provide a theoretical account of populism as being of educational relevance in two respects. First, it argues that the populist logic specifies a set of formal elements by which democratic education could operate as a collective enterprise. Second, it asserts that the notion of populism supplements any congenial understanding of democratic education by bringing political demands, conflicts and affects to the fore. Finally, the paper discusses the risks and possibilities inherent in visualizing populism as an educational modus.

    Place, publisher, year, edition, pages
    Springer, 2017
    Keywords
    Populism, Democratic education, The public, Demands, Affect, Antagonism
    National Category
    Pedagogy Philosophy
    Research subject
    Education
    Identifiers
    urn:nbn:se:oru:diva-54881 (URN)10.1007/s11217-017-9564-5 (DOI)000412461800001 ()2-s2.0-85009848651 (Scopus ID)
    Note

    Funding Agency:

    LUN (The Board of Teacher Education) at Örebro University

    Available from: 2017-01-20 Created: 2017-01-20 Last updated: 2019-09-18Bibliographically approved
  • Wennberg, Pär
    Örebro University, School of Health Sciences.
    Pain management in older persons with hip fractures2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The overall aim of this thesis was to evaluate the preoperative management of pain from the perspectives of a literature overview, emergency medical service pain management, an intervention with a fascia iliaca compartment block and the association between cognitive status and the treatment of pain. Paper 1 is an integrative review of the literature on emergency care in patients with hip fractures or suspected hip fractures. Pain is a major problem for patients suffering a hip fracture when waiting for surgery and it is challenging for health care to provide sufficient pain relief. Listening to the patient’s narrative and the mandatory use of pain scales and pain documentation are necessary to deepen our understanding of individual patients’ needs. Paper 2 is a prospective observational study that explored the prehospital pain levels in 1,426 patients with suspected hip fractures. Furthermore, this study evaluated prehospital pain management. At the site of the injury, patients with hip fractures are often in substantial pain. Seventy-five per cent of the patients received pain relief from the emergency medical service (EMS) care providers and the pain relief was often effective. Several of the patients that did not receive prehospital pain relief had moderate to severe pain. Paper 3 is a randomised placebo-controlled double-blind trial (RCT) of 127 patients waiting for surgery. This RCT evaluated the effect of fascia iliaca compartment blocks (FICB) in relation to pain and medical pain relief, when added to regular preoperative analgesia. FICB improved pain relief when compared with regular analgesia alone (p=0.002). Paper 4 examined whether preoperative pain management with FICB could have an effect on cognitive status in the same 127 patients that were included in Paper 3. No impact on cognitive impairment was proven in this study. Patients with severe cognitive impairment received significantly lower doses of prehospital morphine than patients with higher cognitive status. Prehospital and hospital pain management need to improve. Pain management is especially challenging in persons with cognitive impairment.

    List of papers
    1. Patients with suspected hip fracture in the chain of emergency care: An integrative review of the literature
    Open this publication in new window or tab >>Patients with suspected hip fracture in the chain of emergency care: An integrative review of the literature
    2018 (English)In: International Journal of Orthopaedic and Trauma Nursing, ISSN 1878-1241, E-ISSN 1878-1292, Vol. 29, p. 16-31Article, review/survey (Refereed) Published
    Place, publisher, year, edition, pages
    Elsevier, 2018
    Keywords
    Hip fractures, Pain, Pain assessment, Pain management, Cognitive impairment, Emergency care
    National Category
    Health Care Service and Management, Health Policy and Services and Health Economy Nursing
    Identifiers
    urn:nbn:se:oru:diva-67032 (URN)10.1016/j.ijotn.2017.11.002 (DOI)000432461300004 ()29631852 (PubMedID)2-s2.0-85046756618 (Scopus ID)
    Available from: 2018-05-18 Created: 2018-05-18 Last updated: 2019-09-25Bibliographically approved
    2. Evaluation of the intensity and management of pain before arrival in hospital among 3 patients with suspected hip fractures
    Open this publication in new window or tab >>Evaluation of the intensity and management of pain before arrival in hospital among 3 patients with suspected hip fractures
    (English)Manuscript (preprint) (Other academic)
    National Category
    Other Health Sciences
    Identifiers
    urn:nbn:se:oru:diva-76738 (URN)
    Available from: 2019-09-25 Created: 2019-09-25 Last updated: 2019-09-25Bibliographically approved
    3. Pre-operative pain management with nerve block in patients with hip fractures: a randomized, controlled trial
    Open this publication in new window or tab >>Pre-operative pain management with nerve block in patients with hip fractures: a randomized, controlled trial
    Show others...
    2019 (English)In: International Journal of Orthopaedic and Trauma Nursing, ISSN 1878-1241, E-ISSN 1878-1292, Vol. 33, p. 35-43Article in journal (Refereed) Published
    Abstract [en]

    Introduction: Pain management in patients with hip fractures is a major challenge for emergency care. The objective of this study was to evaluate whether the supplementation of pre-operative analgesia with low-dose fascia iliaca compartment block (FICB) compared with placebo would improve pain relief in patients with hip fractures.

    Methods: A double-blind, randomized, controlled trial was conducted on 127 patients. At hospital admission, a low-dose FICB was administered to patients with hip fractures as a supplement to regular pre-operative analgesia. Patients with and without cognitive impairment were included. The instruments used were a visual analogue scale (VAS), a numerical rating scale and a tool for behavior related pain assessment. The primary endpoint was the change in reported pain on movement from hospital admission to two hours after FICB.

    Results: The intervention group showed improved pain management by mean VAS score for pain on movement compared with the control group (p = 0.002).

    Conclusions: Our results support the use of low-dose FICB as a pain-relieving adjuvant to other analgesics when administered to patients with a hip fracture.

    Place, publisher, year, edition, pages
    Elsevier, 2019
    Keywords
    Hip fractures, Pain, Nerve block, Pain management, Fascia iliaca compartment block, Analgesia
    National Category
    Nursing
    Identifiers
    urn:nbn:se:oru:diva-74410 (URN)10.1016/j.ijotn.2018.11.003 (DOI)000467622900006 ()30876869 (PubMedID)2-s2.0-85065780869 (Scopus ID)
    Note

    Funding Agency:

    Skaraborg Hospital - Örebro County Council

    Available from: 2019-05-28 Created: 2019-05-28 Last updated: 2019-09-25Bibliographically approved
    4. Fascia iliaca compartment block as a preoperative analgesic in elderly patients with hip fractures: effects on cognition
    Open this publication in new window or tab >>Fascia iliaca compartment block as a preoperative analgesic in elderly patients with hip fractures: effects on cognition
    2019 (English)In: BMC Geriatrics, ISSN 1471-2318, E-ISSN 1471-2318, Vol. 19, no 1, article id 252Article in journal (Refereed) Published
    Abstract [en]

    BACKGROUND: Impaired cognition is a major risk factor for perioperative delirium. It is essential to provide good pain control in patients with hip fractures and especially important in patients with severely impaired cognitive status, as they receive less pain medication, have poorer mobility, poorer quality of life and higher mortality than patients with intact cognition. The purpose of this study was to examine the association between preoperative pain management with nerve blocks and cognitive status in patients with hip fractures during the perioperative period.

    METHODS: One hundred and twenty-seven patients with hip fractures participating in a double-blind, randomised, controlled trial were included in this study. At hospital admission, a low-dose fascia iliaca compartment block (FICB) was administered as a supplement to regular analgesia. Cognitive status was registered on arrival at hospital before FICB and on the first postoperative day using the Short Portable Mental Status Questionnaire.

    RESULTS: Changes in cognitive status from arrival at hospital to the first postoperative day showed a positive, albeit not significant, trend in favour of the intervention group. The results also showed that patients with no or a moderate cognitive impairment received 50% more prehospital pain medication than patients with a severe cognitive impairment. FICB was well tolerated in patients with hip fractures.

    CONCLUSION: Fascia iliaca compartment block given to patients with hip fractures did not affect cognitive status in this study. Patients with a cognitive impairment may receive inadequate pain relief after hip fracture and this discrimination needs to be addressed in further studies.

    TRIAL REGISTRATION: EudraCT number 2008-004303-59 date of registration: 2008-10-24.

    Place, publisher, year, edition, pages
    BioMed Central, 2019
    Keywords
    Cognitive impairment, Cognitive status, Hip fractures, Nerve block, Pain, Pain management, Perioperative care
    National Category
    Orthopaedics Geriatrics
    Identifiers
    urn:nbn:se:oru:diva-76426 (URN)10.1186/s12877-019-1266-0 (DOI)000485322000002 ()31510918 (PubMedID)2-s2.0-85072099268 (Scopus ID)
    Note

    Funding Agencies:

    Region Örebro County  

    Skaraborg Hospital 

    Available from: 2019-09-16 Created: 2019-09-16 Last updated: 2019-11-15Bibliographically approved
  • Zekavat, Amir Reza
    Örebro University, School of Science and Technology.
    Application of X-ray Computed Tomography for Assessment of Additively Manufactured Products2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Additive Manufacturing (AM) is a novel method for fabricating parts from three-dimensional model data, usually by joining materials in layer upon layer fashion. The freedom of design in this method has resulted in new possibilities for fabrication of parts with complex geometries. Manufacturing nearnet- shape parts as well as geometrically complex components such as periodic cellular structures that are used in lightweight structural components, has made AM a promising manufacturing method in industry.

    Despite the numerous advantages of the AM methods, the imperfections associated with the manufacturing processes has limited the application of additively manufactured parts. Porosity and surface texture of AM parts especially those fabricated using Laser Powder Bed Fusion (LPBF) methods, have been studied in this thesis. It was observed that the mentioned imperfections have a considerable impact on the mechanical performance of thin-wall structures that are the constituting units of surface-based periodic cellular structures. The quality of internal structure in components fabricated using Fused Deposition Modelling (FDM) and its effect on the strength of those components were the other issues investigated in this thesis.

    In order to investigate the mechanical strength of AM parts, as the result of mentioned mesoscale imperfections, appropriate evaluation methods that are capable of quantitatively assessing these imperfections are required. X-ray Computed Tomography (CT), a non-destructive evaluation method, has shown high capabilities for providing useful and reliable geometrical information of both internal and external features of AM components. The challenges involved with the application of CT for assessment of AM component are also studied in this thesis.

    Apart from the contributions of this thesis on how CT may be used in AM field, the results of this thesis has provided insight into the design process of cellular structures. This thesis has provided essential information about the strength dependency of thin-walls as the result of mesoscale fabrication defects and how these defects are dependent on the selected material and design of the structure.

    List of papers
    1. Measurement of internal features in additive manufactured components by the use of computed tomography
    Open this publication in new window or tab >>Measurement of internal features in additive manufactured components by the use of computed tomography
    2015 (English)Conference paper, Published paper (Refereed)
    Abstract [en]

    Additive manufacturing (AM) is a set of manufacturing processes currently in rapid development providing designersnew freedoms in their designs. One distinct difference from other manufacturing methods is the ability to makecomplex internal features which can be of great benefit for applications in many industries. These features can bechannels, cavities, filled or not filled with powder, parts in parts etc. In order for these advantages to be industriallyapplicable there is a need for robust verification methods for these internal features. X-ray computed tomography (CT)holds the promise of being one of the few powerful tools for non-destructive imaging of internal features. In this work,selective laser sintering (SLS) has been used to manufacture parts of a complex geometry containing internal cavities.The test specimens were manufactured in two different materials; Polyamide12 and Titanium (Ti6Al4V). In order toinvestigate the limitations and controllability of the process, the dimensions of the internal cavities were determinedby a correlation of tactile measurements on external features and CT-data. The results were also compared to computeraided design (CAD) data. This work provides some insight concerning part accuracy of today’s frontier of AM systemsand the ability to measure and characterize internal features using CT.

    Place, publisher, year, edition, pages
    German Society for Non-Destructive Testing, 2015
    Keywords
    Computed tomography, additive manufacturing, internal features, selective laser melting
    National Category
    Mechanical Engineering
    Research subject
    Mechanical Engineering
    Identifiers
    urn:nbn:se:oru:diva-47801 (URN)
    Conference
    Digital Industrial Radiology and Computed Tomography (DIR 2015), Ghent, Belgium, June 22-25, 2015
    Available from: 2016-01-27 Created: 2016-01-27 Last updated: 2019-08-27Bibliographically approved
    2. Investigating the effect of fabrication temperature on mechanical properties of fused deposition modelling parts using X-ray computed tomography
    Open this publication in new window or tab >>Investigating the effect of fabrication temperature on mechanical properties of fused deposition modelling parts using X-ray computed tomography
    2019 (English)In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 100, no 1-4, p. 287-296Article in journal (Refereed) Published
    Abstract [en]

    Fused deposition modeling (FDM) is one of the most common additive manufacturing (AM) techniques for fabricating prototypes as well as functional parts. In this technique, several parameters may influence the part quality and consequently mechanical properties of fabricated components. In this paper, an experimental investigation on effects of fabrication temperature as one of the influential parameters on mechanical properties of manufactured parts is presented. A series of specimens fabricated at temperatures ranging from 180 to 260 C were used for this investigation. X-ray computed tomography (CT) was used in order to non-destructively analyze the internal geometry of the specimens especially the bond between extruded filaments. Finally, the specimens were subjected to a uniaxial tensile load for evaluation of mechanical properties. The results showed that the specimens fabricated at lower temperatures have relatively lower tensile strength despite their considerably higher strain at break. In addition, the specimens fabricated at higher temperature range had significantly higher tensile strength because of the better bond between extruded filaments. The different mechanical responses were highly related to the internal geometry of the specimens and not necessarily the porosity. CT showed great potential as a non-destructive tool for investigation and development of FDM process.

    Place, publisher, year, edition, pages
    Springer London, 2019
    Keywords
    Fused deposition modeling, Computed tomography, Polylactic acid, Additive manufacturing
    National Category
    Other Mechanical Engineering
    Research subject
    Mechanical Engineering
    Identifiers
    urn:nbn:se:oru:diva-69110 (URN)10.1007/s00170-018-2664-8 (DOI)000455946000025 ()2-s2.0-85053832455 (Scopus ID)
    Available from: 2018-09-28 Created: 2018-09-28 Last updated: 2019-08-27Bibliographically approved
    3. Effect of X-ray Computed Tomography Magnification on Surface Morphology Investigation of Additive Manufacturing Surfaces
    Open this publication in new window or tab >>Effect of X-ray Computed Tomography Magnification on Surface Morphology Investigation of Additive Manufacturing Surfaces
    2018 (English)In: 8th Conference on Industrial Computed Tomography, 2018Conference paper, Published paper (Refereed)
    Abstract [en]

    Additive manufacturing (AM) in the last decade has become a widespread manufacturing process. The possibilities that such technologies have provided for manufacturing of complex geometries compared to conventional manufacturing processes has made them popular in many branches of industry. Despite the advantages of these methods, there are limiting issues which needs to be thoroughly investigated. A limiting factor, especially for powder bed AM parts is their undesired surface finish. AM surfaces can be investigated using various methods such as optical or tactile methods, however for complex AM surfaces they are incapable of capturing all details such as deep valleys at surface level. X-ray computed tomography (CT), can provide 3D information of complex AM surfaces and does not have limitations that line of sight and tactile methods have. There are several parameters in CT investigation, which can potentially alter the obtained results. Depending on the CT magnification at which the data is acquired the result specifically surface level detail might be affected. The aim of this study is to investigate the effect of different CT magnifications on surface texture measurement of additively manufactured surfaces. Surface features, including highest peaks and deepest valleys contributing to maximum and minimum thickness of specimen from different magnifications were compared with each other. The result shows that, the lower magnification scans underestimate both peak and valley measurements in comparison to the highest magnification scan. Measurement of valleys and re-entrant features were underestimated at more considerable level. The results from this study provide some understanding regarding surface morphology assessment of AM parts and the level of detail which can be expected depending on the CT magnification.

    Keywords
    Computed tomography, Additive manufacturing, Surface texture
    National Category
    Mechanical Engineering
    Research subject
    Mechanical Engineering
    Identifiers
    urn:nbn:se:oru:diva-65426 (URN)
    Conference
    iCT conference 2018, Wels, Austria, 7 February, 2018
    Available from: 2018-03-02 Created: 2018-03-02 Last updated: 2019-08-27Bibliographically approved
    4. Effect of X-Ray Computed Tomography Magnification on Porosity Analysis of Additively Manufactured Parts
    Open this publication in new window or tab >>Effect of X-Ray Computed Tomography Magnification on Porosity Analysis of Additively Manufactured Parts
    2018 (English)In: World PM2018 Congress Proceedings, 2018Conference paper, Published paper (Refereed)
    Abstract [en]

    X-ray computed tomography has been widely used for inspection of parts manufactured using additive manufacturing (AM) and powder metallurgy (PM). The ability of this method to non-destructively evaluate the porosity content of parts fabricated using AM and PM has made it a reliable method for such inspection. The results obtained from this method are highly dependent on CT acquisition parameters such as the magnification (resolution) at which the part has been scanned. Depending on the size of the parts the scan might need to be performed at lower magnifications which results in loss of information for porosity analysis. Therefore the effect of changing CT magnification on the obtained porosity of an additively manufactured specimen made of AlSi10Mg is investigated in this study. The specimen was scanned at various magnifications resulting in data sets with different resolutions. The porosity content was measured for each data set and the results showed that the porosity measurement using CT is highly dependent on the magnification (resolution) at which the data sets are acquired. The results from this study provided essential information about the porosity content which should be expected depending on the CT magnification.

    Keywords
    Porosity, X-ray computed tomography (CT), Additive manufacturing (AM)
    National Category
    Mechanical Engineering
    Research subject
    Mechanical Engineering
    Identifiers
    urn:nbn:se:oru:diva-69047 (URN)
    Conference
    2018 World Congress on Powder Metallurgy (WORLDPM2018), Beijing, China, September 16-20, 2018
    Available from: 2018-09-25 Created: 2018-09-25 Last updated: 2019-08-28Bibliographically approved
    5. An experimental approach to investigatethe influential parameters on mechanical strength of AlSi10Mgthin-wall structures manufactured by selective laser melting
    Open this publication in new window or tab >>An experimental approach to investigatethe influential parameters on mechanical strength of AlSi10Mgthin-wall structures manufactured by selective laser melting
    Show others...
    (English)Manuscript (preprint) (Other academic)
    National Category
    Other Mechanical Engineering
    Identifiers
    urn:nbn:se:oru:diva-75923 (URN)
    Available from: 2019-08-27 Created: 2019-08-27 Last updated: 2019-08-27Bibliographically approved
    6. Surface Characterization of Additively Manufactured AlSi10Mg andTi6Al4V thin-wall Structures using X-Ray Computed Tomography
    Open this publication in new window or tab >>Surface Characterization of Additively Manufactured AlSi10Mg andTi6Al4V thin-wall Structures using X-Ray Computed Tomography
    (English)Manuscript (preprint) (Other academic)
    National Category
    Other Mechanical Engineering
    Identifiers
    urn:nbn:se:oru:diva-75922 (URN)
    Available from: 2019-08-27 Created: 2019-08-27 Last updated: 2019-08-27Bibliographically approved