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  • 1551.
    Stubleski, Jordan
    et al.
    Örebro University, School of Science and Technology.
    Salihovic, Samira
    Department of Medical Sciences, Molecular Epidemiology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden.
    Lind, P. Monica
    Department of Medical Sciences, Occupational and Environmental Medicine, Uppsala University, Uppsala, Sweden.
    Lind, Lars
    Department of Medical Sciences, Cardiovascular Epidemiology, Uppsala University, Uppsala, Sweden.
    Dunder, Linda
    Department of Medical Sciences, Occupational and Environmental Medicine, Uppsala University, Uppsala, Sweden.
    McCleaf, Philip
    Uppsala Vatten och Avfall AB, Uppsala, Sweden.
    Eurén, Karin
    Uppsala Vatten och Avfall AB, Uppsala, Sweden.
    Ahrens, Lutz
    Swedish University of Agricultural Sciences (SLU), Department of Aquatic Sciences and Assessment, Uppsala, Sweden.
    Svartengren, Magnus
    Department of Medical Sciences, Occupational and Environmental Medicine, Uppsala University, Uppsala, Sweden.
    van Bavel, Bert
    Örebro University, School of Science and Technology. Norwegian Institute for Water Research (NIVA), Oslo, Norway.
    Kärrman, Anna
    Örebro University, School of Science and Technology.
    The effect of drinking water contaminated with perfluoroalkyl substances on a 10-year longitudinal trend of plasma levels in an elderly Uppsala cohort2017In: Environmental Research, ISSN 0013-9351, E-ISSN 1096-0953, Vol. 159, 95-102 p.Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: In 2012, drinking water contaminated with per- and polyfluoroalkyl substances (PFASs), foremost perfluorooctanesulfonic acid (PFOS) and perfluorohexanesulfonic acid (PFHxS) at levels over 20ng/L and 40ng/L, respectively, was confirmed in Uppsala, Sweden.

    OBJECTIVES: We assessed how a longitudinally sampled cohort's temporal trend in PFAS plasma concentration was influenced by their residential location and determined the plausible association or disparity between the PFASs detected in the drinking water and the trend in the study cohort.

    METHODS: The Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) cohort provided plasma samples three times from 2001 to 2014. Individuals maintaining the same zip code throughout the study (n = 399) were divided into a reference (no known PFAS exposure), low, intermediate and high exposure area depending on the proportion of contaminated drinking water received. Eight PFASs detected in the majority (75%) of the cohort's plasma samples were evaluated for significant changes in temporal PFAS concentrations using a random effects (mixed) model.

    RESULTS: PFHxS plasma concentrations continued to significantly increase in individuals living in areas receiving the largest percentage of contaminated drinking water (p < 0.0001), while PFOS showed an overall decrease. The temporal trend of other PFAS plasma concentrations did not show an association to the quality of drinking water received.

    CONCLUSIONS: The distribution of contaminated drinking water had a direct effect on the trend in PFHxS plasma levels among the different exposure groups, resulting in increased concentrations over time, especially in the intermediate and high exposure areas. PFOS and the remaining PFASs did not show the same relationship, suggesting other sources of exposure influenced these PFAS plasma trends.

  • 1552.
    Suares Rocha, Paula
    et al.
    University of Heidelberg.
    Keiter, Steffen
    Örebro University, School of Science and Technology.
    Pompeo, Marcelo Luiz Martins
    University of Sao Paulo.
    Mariani, Carolina Fioriollo
    University of Sao Paulo.
    Brandimarte, Ana Lúcia
    University of Sao Paulo.
    Seiler, Thomas-Benjamin
    University of Heidelberg.
    Kosmehl, Thomas
    University of Heidelberg.
    Böttcher, Melanie
    University of Heidelberg.
    Wölz, Jan
    University of Heidelberg.
    Braunbeck, Thomas
    University of Heidelberg.
    Storch, Volker
    University of Heidelberg.
    Hollert, Henner
    University of Heidelberg.
    Weight-of-Evidence-Studie zur Sedimentbelastung des Tietê River in Brasilien2006In: Umweltwissenschaften und Schadstoff-Forschung, ISSN 0934-3504, Vol. 18, no 1, 70- p.Article in journal (Other academic)
  • 1553.
    Sundberg, Bodil
    Örebro University, School of Science and Technology.
    The conflict within the role: a longitudinal study of preschool student teachers' developing competence in and attitudes towards science teaching in relation to developing a professional role2013In: Journal of Early Childhood Teacher Education, ISSN 1090-1027, E-ISSN 1745-5642, Vol. 34, no 1, 80-94 p.Article in journal (Refereed)
    Abstract [en]

    The aim of this exploratory, longitudinal study was to describe an overall picture ofhow perceptions of the teacher role and attitudes toward science and science teachingdevelop and interact during preschool teacher education, and how this in turn influencesbehavior when students are engaged in teaching science. Sixty-five students enrolled in apreschool teacher education program at a Swedish university were followed throughouttheir teacher education. The study used a phenomenographic approach within a theoreticalframework of sociocultural and situated learning perspective. Questionnaires withopen and closed questions were combined with interviews. The results show that in spiteof growing competence and confidence, many of the students still found science activitiesto be awkward in preschool, mainly due to a wish to protect the children from schoolculture. The results have implications for teacher education and the preschool community,showing a need to problematize the purpose of teaching science in preschool andthe meaning of pedagogical content knowledge in this context.

  • 1554.
    Sundberg, Bodil
    et al.
    Örebro University, School of Science and Technology.
    Areljung, Sofie
    Department of Science and Mathematics Education, Umeå University, Umeå, Sweden.
    Due, Karin
    Department of Science and Mathematics Education, Umeå University, Umeå, Sweden.
    Ekström, Kenneth
    Applied Educational Science, Umeå University, Umeå, Sweden.
    Ottander, Christina
    Department of Science and Mathematics Education, Umeå University, Umeå, Sweden.
    Tellgren, Britt
    Örebro University, School of Humanities, Education and Social Sciences.
    Understanding preschool emergent science in a cultural historical context through Activity Theory2016In: European Early Childhood Education Research Journal, ISSN 1350-293X, E-ISSN 1752-1807, Vol. 24, no 4, 567-580 p.Article in journal (Refereed)
    Abstract [en]

    The aim of this study is to explore how cultural factors interact with preschool teachers’ shaping of activities with science content, and also how Activity Theory (AT) as a theoretical framework can be useful for examining interrelations within preschool systems. Qualitative data was collected from three preschools in the form of guided group discussions with preschool teachers, observations and video recordings of activities, and stimulated recall discussions based on the recorded practices. The preschools displayed diverse approaches for experiencing and learning science, some with great creativity. In all preschools learning was integrated with care, upbringing and play. To support children’s interest and confidence was central. How science activities were shaped mainly depended on how children’s interests were allowed to govern practice. The use of AT as an analytical tool was proven to be effective in identifying the elements, relationships and tensions crucial for understanding the framing of science activities. 

  • 1555.
    Sundberg, Bodil
    et al.
    Örebro University, School of Science and Technology. Örebro universitet, Sweden.
    Ottander, Christina
    Institutionen för naturvetenskapernas och matematikens didaktik, Umeå universitet, Umeå, Sverige.
    Science in Preschool – A Foundation for Education for Sustainability?: a View from Swedish Preschool Teacher Education.2014In: Research in Early Childhood Education for Sustainability: international perspectives and provocations / [ed] Susan Elliott, Julie Davis, Oxon: Routledge, 2014, 280-293 p.Chapter in book (Other academic)
    Abstract [en]

    In this chapter we elaborate on how science encounters can be used within education for sustainability (EfS) in preschool practice as a means of empowering children to engage with sustainability. We acknowledge recent research arguing for a rethink of what science teaching in preschool can be. Such rethinking involves a shift from viewing science in preschool as mainly nature experiences towards introducing young children to science inquiry. By doing so, the interplay between knowledge, values and the ways in which humans build and make use of new knowledge can become visible thus, laying a foundation for EfS. Implementation of science inquiry processes in preschools would, however, necessitate changes in preschool teachers’ personal and professional views of science, nature and pedagogy. In our research we have explored how competence in inquiry-based teaching may, or may not, develop during pre-service preschool teacher education. We have also observed how competence can develop, but still not be realized in practice due to culturally and historically grounded attitudes and notions about science and about teaching. Drawing on these findings, we initiate discussion about how pre-service and in-service teacher education can support a broader view of teaching and science to fit the ‘community of practice’ of preschools and hence make a contribution to EfS. Our suggestions highlight the need for pre-service and in-service education to explore the historical/cultural contexts of preschool practices and teachers’ roles in raising children’s awareness of their own scientific observations and science learning processes. We also stress the need for stronger co-operation between teacher educators and teachers in practicum settings to ensure that pre-service students experience preschool environments where they have opportunities to challenge norms and practice inquiry teaching skills that are foundational for EfS. 

  • 1556.
    Sundberg, Bodil
    et al.
    Örebro University, School of Science and Technology. Örebro universitet, Sweden.
    Ottander, Christina
    Umeå universitet, Institutionen för naturvetenskapernas och matematikens didaktik.
    The diversity of science activities in Swedish preschools2014In: Symposium: Early childhood science education: Research methodology and findings of fieldworks, 2014Conference paper (Refereed)
  • 1557.
    Sundberg, Bodil
    et al.
    Örebro University, School of Science and Technology. Örebro universitet.
    Ottander, Christina
    Umeå university, Umeå, Sweden.
    What are the voices of becoming practitioners telling us about science in pre-school?: Pre-school student teachers´ attitudes towards science and science teaching - a longitudinal study.2010In: 20th EECERA ANNUAL CONFERENCE. KNOWLEDGE AND VOICE IN EARLY CHILDHOOD: Who knows, who speaks, who listens?, 2010, 216-216 p.Conference paper (Refereed)
    Abstract [en]

    The aim of this study is to investigate the relationship between the developing professional identity and attitudes towards science teaching among student pre-school teachers. We see professional identity as a dynamic equilibrium between the professional self-image and the variety of roles (pre-school) teachers feel they have to play. Accordingly, professional identity can change over time through relevant others, events and experiences. In this longitudinal study, 65 students enrolled in an art and science dominated teacher programme have been followed since the start in august 2008. Results are presented from 4 consecutive questionnaires and an individual interview of 8 students. The results show that sceptical attitudes towards science decreased significantly after one year of science studies. On the contrary hesitance towards holding structured scientific activities persisted throughout the year. Results from the individual interviews confirm these findings. Here, the descriptions of perceived relevant roles of their profession are dominated by themes of caring and supporting, not teaching. The reluctance towards science teaching in early years thus appear to be more connected to student teachers’ view of the professional preschool teacher role, where structured teaching not is a pronounced part, than to negative attitudes towards science itself. These findings thereby contradict the general idea that the ambiguity about teaching science in pre-school among student teachers is connected to negative attitudes toward science as a subject. This new perspective suggests a need to integrate a discussion of the pre-school teacher role and professional identity into science courses for becoming pre-school teachers.

  • 1558.
    Sundberg, Bodil
    et al.
    Örebro University, School of Science and Technology. Örebro universitet, Sweden.
    Spante, Maria
    Department of Economy and Informatics, University West, Trollhättan, Sweden .
    Stenlund, Jörgen. I
    Örebro University, School of Science and Technology.
    Disparity in practice: Diverse strategies among teachers implementing interactive whiteboards into teaching practice in two Swedish primary schools2012In: Learning, Media & Technology, ISSN 1743-9884, E-ISSN 1743-9892, Vol. 37, no 3, 253-270 p.Article in journal (Refereed)
    Abstract [en]

    This paper reports on a project aimed at identifying and exploring the development and implementation processes of teaching practices with interactive whiteboards (IWBs) in two Swedish K-6 schools. The purpose of the project was to generate results and insights of value when preparing student teachers for professional use of IWBs and to give school leaders guidelines when implementing IWBs. A range of methods were used to collect rich and varied empirical materials in this exploratory project. Judging from our data, it was obvious that the implementation process of IWBs, just like other information and communication technology initiatives, is very technology-oriented, but also dependent on attitudes. Over the course of time in the project, different strategies emerged among the teachers regarding whether and how they used the IWBs in their lectures. It also became increasingly clear during the study that there is a distinction between technical interactivity and pedagogical interactivity. Our results further suggest that training is needed when introducing these boards for future users. This training should include both technical instructions and pedagogical discussions.

    © 2012 Copyright Taylor and Francis Group, LLC.

  • 1559.
    Suvitaival, T.
    et al.
    Steno Diabetes Center, Gentofte, Denmark.
    Mantere, O.
    Mental Health Unit, National Institute for Health and Welfare, Helsinki, Finland; Department of Psychiatry, McGill University, Montréal, QC, Canada; Bipolar Disorders Clinic, Douglas Mental Health University Institute, Montréal, QC, Canada.
    Kieseppä, T.
    Mental Health Unit, National Institute for Health and Welfare, Helsinki, Finland; Department of Psychiatry, Helsinki University and Helsinki University Hospital, Helsinki, Finland.
    Mattila, I.
    Steno Diabetes Center, Gentofte, Denmark.
    Pöhö, P.
    Faculty of Pharmacy, University of Helsinki, Helsinki, Finland.
    Hyötyläinen, Tuulia
    Örebro University, School of Science and Technology. Steno Diabetes Center, Gentofte, Denmark.
    Suvisaari, J.
    Mental Health Unit, National Institute for Health and Welfare, Helsinki, Finland.
    Orešič, M.
    Steno Diabetes Center, Gentofte, Denmark; Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku, Finland.
    Serum metabolite profile associates with the development of metabolic co-morbidities in first-episode psychosis2016In: Translational Psychiatry, ISSN 2158-3188, E-ISSN 2158-3188, Vol. 6, no 11, e951Article in journal (Refereed)
    Abstract [en]

    Psychotic patients are at high risk for developing obesity, metabolic syndrome and type 2 diabetes. These metabolic co-morbidities are hypothesized to be related to both treatment side effects as well as to metabolic changes occurring during the psychosis. Earlier metabolomics studies have shown that blood metabolite levels are predictive of insulin resistance and type 2 diabetes in the general population as well as sensitive to the effects of antipsychotics. In this study, we aimed to identify the metabolite profiles predicting future weight gain and other metabolic abnormalities in psychotic patients. We applied comprehensive metabolomics to investigate serum metabolite profiles in a prospective study setting in 36 first-episode psychosis patients during the first year of the antipsychotic treatment and 19 controls. While corroborating several earlier findings when comparing cases and controls and the effects of the antipsychotic medication, we also found that prospective weight gain in psychotic patients was associated with increased levels of triacylglycerols with low carbon number and double-bond count at baseline, that is, lipids known to be associated with increased liver fat. Our study suggests that metabolite profiles may be used to identify the psychotic patients most vulnerable to develop metabolic co-morbidities, and may point to a pharmacological approach to counteract the antipsychotic-induced weight gain.

  • 1560.
    Suvitaival, Tommi
    et al.
    Steno Diabetes Center Copenhagen, DK-2820 Gentofte, Denmark.
    Bondia-Pons, Isabel
    Steno Diabetes Center Copenhagen, DK-2820 Gentofte, Denmark.
    Yetukuri, Laxman
    Institute for Molecular Medicine Finland, University of Helsinki, Helsinki, Finland; VTT Technical Research Centre of Finland, Espoo, Finland.
    Pöhö, Päivi
    VTT Technical Research Centre of Finland, Espoo, Finland; Faculty of Pharmacy, University of Helsinki, Helsinki, Finland.
    Nolan, John J
    Steno Diabetes Center Copenhagen, DK-2820 Gentofte, Denmark.
    Hyötyläinen, Tuulia
    Örebro University, School of Science and Technology. Steno Diabetes Center Copenhagen, Gentofte, Denmark; Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku, Finland; Department of Chemistry, Örebro University, Örebro, Sweden.
    Kuusisto, Johanna
    Institute of Clinical Medicine, Internal Medicine, University of Eastern Finland and Kuopio University Hospital, Kuopio, Finland.
    Orešič, Matej
    Örebro University, School of Medical Sciences. Steno Diabetes Center Copenhagen, DK-2820 Gentofte, Denmark Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, FI-20520 Turku, Finland.
    Lipidome as a predictive tool in progression to type 2 diabetes in Finnish men2017In: Metabolism: Clinical and Experimental, ISSN 0026-0495, E-ISSN 1532-8600, S0026-0495(17)30230-5Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: There is a need for early markers to track and predict the development of type 2 diabetes mellitus (T2DM) from the state of normal glucose tolerance through prediabetes. In this study we tested whether the plasma molecular lipidome has biomarker potential to predicting the onset of T2DM.

    METHODS: We applied global lipidomic profiling on plasma samples from well-phenotyped men (107 cases, 216 controls) participating in the longitudinal METSIM study at baseline and at five-year follow-up. To validate the lipid markers, an additional study with a representative sample of adult male population (n = 631) was also conducted. A total of 277 plasma lipids were analyzed using the lipidomics platform based on ultra-performance liquid chromatography coupled to time-of-flight mass spectrometry. Lipids with the highest predictive power for the development of T2DM were computationally selected, validated and compared to standard risk models without lipids.

    RESULTS: A persistent lipid signature with higher levels of triacylglycerols and diacyl-phospholipids as well as lower levels of alkylacyl phosphatidylcholines was observed in progressors to T2DM. Lysophosphatidylcholine acyl C18:2 (LysoPC(18:2)), phosphatidylcholines PC(32:1), PC(34:2e) and PC(36:1), and triacylglycerol TG(17:1/18:1/18:2) were selected to the full model that included metabolic risk factors and FINDRISC variables. When further adjusting for BMI and age, these lipids had respective odds ratios of 0.32, 2.4, 0.50, 2.2 and 0.31 (all p < 0.05) for progression to T2DM. The independently-validated predictive power improved in all pairwise comparisons between the lipid model and the respective standard risk model without the lipids (integrated discrimination improvement IDI > 0; p < 0.05). Notably, the lipid models remained predictive of the development of T2DM in the fasting plasma glucose-matched subset of the validation study.

    CONCLUSION: This study indicates that a lipid signature characteristic of T2DM is present years before the diagnosis and improves prediction of progression to T2DM. Molecular lipid biomarkers were shown to have predictive power also in a high-risk group, where standard risk factors are not helpful at distinguishing progressors from non-progressors.

  • 1561. Svedendahl, Mikael
    et al.
    Johansson, Peter
    Örebro University, School of Science and Technology.
    Kall, Mikael
    Complete light annihilation in an ultrathin layer of gold nanoparticles2013In: Nano letters (Print), ISSN 1530-6984, E-ISSN 1530-6992, Vol. 13, no 7, 3053-3058 p.Article in journal (Refereed)
    Abstract [en]

    We experimentally demonstrate that an incident light beam can be completely annihilated in a single layer of randomly distributed, widely spaced gold nanoparticle antennas. Under certain conditions, each antenna dissipates more than 10 times the number of photons that enter its geometric cross-sectional area. The underlying physics can be understood in terms of a critical coupling to localized plasmons in the nanoparticles or, equivalently, in terms of destructive optical Fano interference and so-called coherent absorption.

  • 1562.
    Svedlund, Maria
    Örebro University, School of Science and Technology.
    Laborativ matematikundervisning i årskurs 5: En jämförelse mellan lärare och elevers uppfattning angående användningen av laborativt material2015Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The interest of using laboratory manipulative has increased during the last couple of years. The aim with this study is to find out and make a comparison between teacher and student perceptions and opinions regarding the use of learning materials in mathematics education. The study was conducted on four teachers in Örebro and their classes in grade 5. The results indicate that the use of learning materials facilitates the understanding and makes the mathematics more interesting for many students according both to students and teachers. Teachers’ and students’ opinion differs regarding the frequency of use of laboratory manipulative. The teachers’ opinion is that the material is used more. The answer from teachers shows that they think that learning materials gives an opportunity to connect the education with every day’s mathematics. It also creates a dual communication between students and teachers.

  • 1563.
    Svedlund, Marie
    Örebro University, School of Science and Technology.
    Laborativt material i matematikundervisning: Förbättras elevernas kunskaper, vilken uppfattning har lärare och elever samt vad påverkar användningen?2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Swedish students continue to score lower in mathematics compared to students from other countries, according to the latest PISA survey. The purpose with this study is to answer whether the use of manipulative material can help increase students' mathematical skills, and also find out which underlying factors are affecting this. This qualitative literature study is based on nine previous studies. The result shows that the use of manipulative helps to increase the students’ mathematical skills. Other factors plays a significant role in the degree of contribution and how the material is used, the teachers' opinion of manipulative material, the combination of clear instructions for the students and the best adapted manipulative for respective mathematic problem and the teachers skills to make use of the materials in their teaching.

  • 1564.
    Svensson, Fredrik
    et al.
    Örebro University, School of Science and Technology.
    Wåhlstedt, Sebastian
    Örebro University, School of Science and Technology.
    Metodutveckling av Additivt Tillverkade (AT) produkter med efterbearbetning i CNC styrda maskiner med enkel identifiering av nollpunkt2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been carried out in Karlskoga at the two companies, Lasertech LSH AB and PartnerTech Karlskoga AB, where the assignment consisted of using a methodological development to find a general approach that can be used to simplify the processing of an additive manufactured (AM) part. The challenge is to rig and calibrate a detail in a CNC machine that is nearly finished that lacks obvious faces to rig and calibrate the part in the machine. The aim of the work is to find a general method that can be used to resolve these difficulties, leading to a safer and more efficient manufacturing. Parallel to the solution of the problem, a case study will also be done where both companies have a product that will be additive manufactured (AM) and processed in the CNC machine. The problems were clarified by using a functional-medium-trees (funktionsmedelträd) and solutions were developed using the concept generation to get as many good solutions as possible. By developing these concepts and the ability to combine these with each other a method that solves the problems with the rigging and calibration was created and proved to be useful in the case study. We see these concepts as general and a good solutions to the problems above. Further work and training will be required to further test the methods and increase knowledge about AM production to facilitate the manufacturing process.

  • 1565.
    Szilva, A.
    et al.
    Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Uppsala, Sweden.
    Thonig, D.
    Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Uppsala, Sweden.
    Bessarab, P. F.
    Science Institute of the University of Iceland, Reykjavik, Iceland; Department of Nanophotonics and Metamaterials, ITMO University, St. Petersburg, Russia.
    Kvashnin, Y. O.
    Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Uppsala, Sweden.
    Rodrigues, D. C. M.
    Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Uppsala, Sweden; Faculdade de Física, Universidade Federal do Pará, Belém, Brazil.
    Cardias, R.
    Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Uppsala, Sweden; Faculdade de Física, Universidade Federal do Pará, Belém, Brazil.
    Pereiro, M.
    Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Uppsala, Sweden.
    Nordström, L.
    Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Uppsala, Sweden.
    Bergman, A.
    Maison de la Simulation, USR 3441, CEA-CNRS-INRIA-Université Paris-Sud-Université de Versailles, Gif-sur-Yvette, France; INAC-MEM, CEA, Grenoble, France.
    Klautau, A. B.
    Faculdade de Física, Universidade Federal do Pará, Belém, Brazil.
    Eriksson, Olle
    Örebro University, School of Science and Technology. Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Uppsala, Sweden.
    Theory of noncollinear interactions beyond Heisenberg exchange: Applications to bcc Fe2017In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 96, no 14, 144413Article in journal (Refereed)
    Abstract [en]

    We show for a simple noncollinear configuration of the atomistic spins (in particular, where one spin is rotated by a finite angle in a ferromagnetic background) that the pairwise energy variation computed in terms of multiple-scattering formalism cannot be fully mapped onto a bilinear Heisenberg spin model even in the absence of spin-orbit coupling. The non-Heisenberg terms induced by the spin-polarized host appear in leading orders in the expansion of the infinitesimal angle variations. However, an E-g - T-2g symmetry analysis based on the orbital decomposition of the exchange parameters in bcc Fe leads to the conclusion that the nearest-neighbor exchange parameters related to the T-2g orbitals are essentially Heisenberg-like: they do not depend on the spin configuration, and can, in this case, be mapped onto a Heisenberg spin model even in extreme noncollinear cases.

  • 1566.
    Säker, Oscar
    Örebro University, School of Science and Technology.
    Samband mellan ordervolym och kortad ställtid2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This Thesis has been done at Orica Sweden AB, located in Gyttorp a few miles north of Örebro. They are manufacturing blasting equipment, mostly used for mining and construction of roads. To make it explode in correct time, an electric igniter is used. There are other igniters as well, but this thesis is only focused on electrical igniters. Orica needs help with finding out how many products each batch will contain before each changeover. This amount indicates if Orica can afford to pay for all the machines and staff. A changeover is the preparation time it takes before the machine can start manufacturing other types of products. For example, a different kind of product may need a different kind of mounting tool. Also they need help to reduce the time for each changeover. In order to make a good job, this thesis is using surveys and calculations. The method for reducing changeover is SMED, which means that changeovers must not take longer than ten minutes to complete. In present, a changeover can take more than an hour to complete. The result is that changeovers can be reduced with about 34 % (33, 3 hour a month before and 22,06 hour a month after). To calculate the amount of product that has to be produced each time, a method of calculation called break-even point is used. Before the reduced changeover time this volume was equal to 1500 units. After the reduced changeover time the amount was dropped to 1380 units. Also another method was used for this calculation. It is called optimal order quantity, and using this method resulted in the amount of 1699 units before and 1081 units after.

  • 1567.
    Söder, Robert
    et al.
    Örebro University, School of Science and Technology.
    Liljerås, Magnus
    Örebro University, School of Science and Technology.
    VRA-PROGRAMVARA MED TILLHÖRANDE STYRELEKTRONIK2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been done at the Unversity of Örebro for Örebro University Hospital (USÖ). In our work we have developed a product for hearing tests to determine hearing thresholds of small children. Our product contains software and a control surface for controlling two separate screens. One of the demands was that our software could handle big file libraries. Reliability and simplicity were essential for the user.

    In our work we have utilized programming of both microcontrollers and Windows software. We have also connected the control surface with the software via serial communication.

    We have developed a prototype which can be seen as a finished product. Our product is safe for future use and compatible with newer versions of the Windows operating system. As of yet, it has not been tested in a real life setting.

  • 1568.
    Söderström, Mikael
    Örebro University, School of Science and Technology.
    Sensorkontroll via WIFI2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been conducted at

    H&D Wireless AB in Stockholm. H&D Wireless AB is a Company specializing in WiFi circuit boards to be used in combination with leading microcontrollers. Their main product, HDG104, is considered to be the market leader in terms of size, power consumption, radio range, speed and price.

    H&D Wireless

    would now like to connect various sensors and display their values through a server on their boards. This thesis included examination of market available sensors, how they are used and programing to use the selected sensors.

    All work carried out at its premises in Kista, Stockholm.

    Two different interfaces were selected for implementation; 1-wire and I

    2C. 1-wire components, I have managed to connect, display on the website and report values automatically to www.temperatur.nu for graphs of temperature. Realization of I2C communication to components failed because the focus was on the 1-wire components.

  • 1569.
    Söderström, Therese
    Örebro University, School of Science and Technology.
    En undersökning av hur lärare i hem- och konsumentkunskap inom Örebro kommun arbetar med olika miljöfrågor i undervisningen och hur miljöanpassade deras inköp är2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Hem- och konsumentkunskapen beskrivs som ett viktigt ämne när det kommer till frågor om globalisering, konsumtion och hälsa. Den nya kursplanen som gavs ut år 2011, för hem- och konsumentkunskap, har enligt Skolverket fått ett stort fokus på hur den enskilde individen kan bidra till en hållbar utveckling genom olika konsumtions val och handlingar i hemmet. Syftet med denna studie är att undersöka hur lärare i hem- och konsumentkunskap inom Örebro kommun arbetar med olika miljöfrågor i undervisningen samt undersöka hur miljöanpassade deras inköp är. Genom enkäter och intervjuer insamlades information av 13 hem-och konsumentkunskapslärare i Örebro, om hur de arbetar med miljön i undervisningen samt hur miljöanpassade deras inköp är. Resultatet visar att inköp av svenska råvaror har fått störst fokus medan inköp av ekologiskt, närproducerade och säsongsanpassade råvaror görs i mindre utsträckning. Flera utav lärarna, som har en äldre hem- och konsumentkunskapsutbildning, känner att de inte har tillräckligt med miljökunskaper för vad som krävs i undervisningen. Sju av de 13 lärarna använder sig av uppgifter där eleverna ska ta hänsyn till miljön medan de resterande fem gör det ibland. En återkommande faktor till varför inköp av säsongsanpassade, ekologiska och närproducerade råvaror är låg är enligt lärarna på grund av den bristande ekonomin. En slutsats som kan dras är att hem- och konsumentkunskapen får begränsat med tid och resurser för att kunna utveckla och anpassa undervisningen efter den nya kursplanen. 

  • 1570.
    Sørensen, Mads Peter
    et al.
    Department of Applied Mathematics and Computer Science, Technical University of Denmark, Kongens Lyngby, Denmark.
    Falsig Pedersen, Niels
    Department of Applied Mathematics and Computer Science, Technical University of Denmark, Kongens Lyngby, Denmark.
    Ögren, Magnus
    Örebro University, School of Science and Technology.
    The dynamics of magnetic vortices in type II superconductors with pinning sites studied by the time dependent Ginzburg–Landau model2017In: Physica. C, Superconductivity, ISSN 0921-4534, E-ISSN 1873-2143, Vol. 533, 40-43 p.Article in journal (Refereed)
    Abstract [en]

    We investigate the dynamics of magnetic vortices in type II superconductors with normal state pinning sites using the Ginzburg–Landau equations. Simulation results demonstrate hopping of vortices between pinning sites, influenced by external magnetic fields and external currents. The system is highly nonlinear and the vortices show complex nonlinear dynamical behaviour.

  • 1571.
    Tahir, Diana
    Örebro University, School of Science and Technology.
    Om förhållandet mellan lärares uppfattningar om matematik, lärande och undervisning och deras användning av matematikböcker2016Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Swedish teachers tend to use mathematics textbooks in their teaching to a large extent. How teachers’ beliefs impact their teaching is however, debated. Therefore, this study investigated the relationship between teachers’ use of mathematics textbooks and their beliefs about mathematics, mathematics teaching and learning mathematics. Eight 1-3 grade teachers completed a questionnaire measuring their use of mathematics textbooks and their beliefs, three of these were interviewed. The results indicate that the teachers can agree with both a dynamic and a static view of the nature of mathematics, and both a constructivist and traditional view of mathematics learning and teaching.

    The results also show that the teacher that uses the least amount of tasks from mathematics textbooks is the teacher that to the largest extent holds a constructivist view, while the teacher that uses the most amount of tasks from mathematics textbooks is the teacher that to the largest extent holds a dynamic and problem solving view. The teacher that’s in between the other teachers when it comes to where the tasks are taken from is the teacher that to the largest extent holds a static, platonist and instrumentalist view. However, if beliefs about mathematics, mathematics teaching and learning mathematics are seen as a unit there is no correlation between the use of mathematics textbooks and beliefs.

  • 1572.
    Talvitie Svedlin, Annie
    Örebro University, School of Science and Technology.
    Matematiksvårigheter och lässvårigheter: En undersökning om skillnader mellan elever i matematiksvårigheter och elever i matematik- och lässvårigheter2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This literature study intends to compile and narrate peer-reviewed articles about mathematics teaching. These articles that is compiled to cultivate the differences there is between students with mathematics disabilities and students with mathematic disabilities and reading disabilities. The result of this study demonstrates differences in working memory, phonological awareness, and problem solving in students with mathematic disabilities compared to students with both mathematics disabilities and reading disabilities. The most significant factor in the literature is that students who have both mathematical disabilities and reading disabilities have significantly lower results in working memory, phonological awareness, and problem solving.

  • 1573.
    Temnerud, Johan
    et al.
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden; Swedish Meteorological and Hydrological Institute, Research Department, Norrköping, Sweden .
    Düker, Anders
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Karlsson, Stefan
    Örebro University, School of Science and Technology.
    Allard, Bert
    Örebro University, School of Science and Technology.
    Bishop, Kevin
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden; Department of Earth Sciences, Uppsala University, Uppsala, Sweden .
    Föster, Stephan
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden .
    Köhler, Stephan
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden .
    Spatial patterns of some trace elements in four Swedish stream networks2013In: Biogeosciences, ISSN 1726-4170, E-ISSN 1726-4189, Vol. 10, no 3, 1407-1423 p.Article in journal (Refereed)
    Abstract [en]

    Four river basins in southern Sweden, with catchment sizes from 0.3 to 127 km2 (median 1.9), were sampled in October∼2007. The 243 samples were analysed for 26 trace elements (Ag, As, Au, Ba, Be, Bi, Cd, Co, Cr, Cu, Ga, Ge, In, La, Li, Mo, Ni, Pb, Sb, Se, Sn, Tl, Ti, U, V and Zn) to identify spatial patterns within drainage networks. The range and median of each element were defined for different stream orders, and relationships to catchment characteristics, including deposition history, were explored. The sampling design made it possible to compare the differences along 40 stream reaches, above and below 53 stream junctions with 107 tributaries and between the 77 inlets and outlets of 36 lakes. The largest concentration differences (at reaches, junctions and lakes) were observed for lakes, with outlets usually having lower concentration compared to the inlets for As, Ba, Be, Bi, Cd, Co, Cr, Ga, Ge, Ni, Pb, Sn, Ti, Tl, U, V and Zn. Significantly lower concentrations were observed for Cd and Co when comparing headwaters with downstream sites in each catchment. Common factor analysis (FA) revealed that As, Bi, Cr, Ga, Ge, Tl and V co-vary positively with Al, Fe and total organic carbon (TOC) and negatively with La, Li and pH. The strong removal of a large number of trace elements when passing through lakes is evident though in the FA, where lake surface coverage plots opposite to many of those elements. Forest volume does not respond in a similar systematic fashion and, surprisingly, the amount of wetland does not relate strongly to either Fe or TOC at any of the rivers. A better understanding of the quantitative removal of organic carbon and iron will aid in understanding trace element fluxes from landscapes rich in organic matter and iron.

  • 1574.
    Terzic, Kasim
    et al.
    School of Computer Science, University of St Andrews, Scotland, United Kingdom; Department of Electronic Engineering and Computer Science, University of the Algarve, Portugal.
    Krishna, Sai
    Örebro University, School of Science and Technology. Department of Electronic Engineering and Computer Science, University of the Algarve, Portugal.
    du Buf, J. M. H.
    Department of Electronic Engineering and Computer Science, University of the Algarve, Portugal.
    Texture features for object salience2017In: Image and Vision Computing, ISSN 0262-8856, E-ISSN 1872-8138, Vol. 67, 43-51 p.Article in journal (Refereed)
    Abstract [en]

    Although texture is important for many vision-related tasks, it is not used in most salience models. As a consequence, there are images where all existing salience algorithms fail. We introduce a novel set of texture features built on top of a fast model of complex cells in striate cortex, i.e., visual area V1. The texture at each position is characterised by the two-dimensional local power spectrum obtained from Gabor filters which are tuned to many scales and orientations. We then apply a parametric model and describe the local spectrum by the combination of two one-dimensional Gaussian approximations: the scale and orientation distributions. The scale distribution indicates whether the texture has a dominant frequency and what frequency it is. Likewise, the orientation distribution attests the degree of anisotropy. We evaluate the features in combination with the state-of-the-art VOCUS2 salience algorithm. We found that using our novel texture features in addition to colour improves AUC by 3.8% on the PASCAL-S dataset when compared to the colour-only baseline, and by 62% on a novel texture-based dataset.

  • 1575.
    Thomas, Peter
    et al.
    Marine Science Institute, The University of Texas at Austin, Port Aransas, Texas, USA.
    Converse, Aubrey
    Marine Science Institute, The University of Texas at Austin, Port Aransas, Texas, USA.
    Berg, Håkan A.
    Örebro University, School of Science and Technology.
    ZIP9, a novel membrane androgen receptor and zinc transporter protein2017In: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, S0016-6480(17)30341-6Article in journal (Refereed)
    Abstract [en]

    Rapid, androgen actions initiated at the cell surface have been reported in a variety of vertebrate cells, including several macrophage and prostate cancer cell lines that lack the nuclear androgen receptor. However, until recently the identity of the novel membrane androgen receptor (mAR) mediating these nonclassical androgen actions remained unknown. In 2014, a novel mAR unrelated to nuclear androgen receptors was identified in Atlantic croaker ovaries as the zinc transporter protein, ZIP9. ZIP9 is one of the 14 members of the ZIP (ZRT-and Irt-like Protein, SLC39A) family that regulates zinc homeostasis by transporting zinc across cell and organelle membranes into the cytoplasm. Zinc is a micronutrient critical for the maintenance of physiological and cellular processes, such as development, growth, protein assembly and activity, signaling, and apoptosis. Both croaker ZIP9 and human ZIP9 proteins have the binding characteristics of high affinity, specific mARs, and are coupled to G proteins. Testosterone induces apoptosis through ZIP9 in croaker granulosa cells and in human breast and prostate cancer cells by a unique mechanism involving increases in both second messengers and intracellular free zinc concentrations. ZIP9 also mediates testosterone regulation of tight junction formation in Sertoli cells and nonclassical testosterone signaling in spermatogenic cells. ZIP9 acts through several signal transduction pathways, a stimulatory G protein (Gs) in granulosa cells, an inhibitory one (Gi) in cancer cells, and a Gq11 one (Gnα11) in spermatogenic cells. ZIP9 has a very broad tissue distribution and is predicted to mediate numerous and diverse nonclassical androgen actions in vertebrates.

  • 1576.
    Thomas, Peter
    et al.
    UTMSI, University of Texas at Austin, USA.
    Pang, Yefei
    UTMSI, University of Texas at Austin, USA.
    Dong, Jing
    UTMSI, University of Texas at Austin, USA.
    Berg, Håkan
    Örebro University, School of Science and Technology. UTMSI, University of Texas at Austin, USA.
    Identification and characterization of membrane androgen receptors in the ZIP9 zinc transporter subfamily: II. Role of human ZIP9 in testosterone-induced prostate and breast cancer cell apoptosis2014In: Endocrinology, ISSN 0013-7227, E-ISSN 1945-7170, Vol. 155, no 11, 4250-4265 p.Article in journal (Refereed)
    Abstract [en]

    Recently we discovered a cDNA in teleost ovarian follicle cells belonging to the zinc transporter ZIP9 subfamily encoding a protein with characteristics of a membrane androgen receptor (mAR). Here we demonstrate that human ZIP9 expressed in MDA-MB-468 breast cancer cells and stably overexpressed in human prostate cancer PC-3 cells (PC-3-ZIP9) also displays the ligand binding and signaling characteristics of a specific, high-affinity mAR. Testosterone treatment of MDA-MB-468 and PC-3-ZIP9 cells caused activation of G proteins and second messenger pathways as well as increases in intracellular free zinc concentrations that were accompanied by induction of apoptosis. [3H]-Testosterone binding and these responses were abrogated in MDA-MB-468 cells after ZIP9 siRNA treatment and absent in PC-3 cells transfected with empty vector, confirming that ZIP9 functions as an mAR. Testosterone treatment caused upregulation of proapoptotic genes Bax, p53 and JNK in both cell lines and increased expression of Bax, Caspase 3 and cytochrome C proteins. Treatment with a zinc chelator (TPEN) or a MAP kinase inhibitor (PD98059) blocked testosterone induced increases in Bax, p53 and JNK mRNA expression. The results suggest that both androgen signaling and zinc transporter functions of ZIP9 mediate testosterone promotion of apoptosis. ZIP9 is widely expressed in human tissues and upregulated in malignant breast and prostate tissues, suggesting it is a potential therapeutic target for treating breast and prostate cancers. These results provide the first evidence for a mechanism mediated by a single protein through which intracellular steroidandzinc signaling pathways interact to regulate physiological functions in mammalian cells.

  • 1577.
    Thomsson, Sofie
    Örebro University, School of Science and Technology.
    Frågornas betydelse i det matematiska klassrummet: En litteraturstudie om lärarens val av frågetyper och vilka effekter det kan få på elevers lärande2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The interaction in the classroom affects whether student results are promoted. The teacher can

    control the interaction of the classroom, this can be done by the teacher asking questions to

    the students. These different question types affect students' continued knowledge

    development and can give students a lot of opportunity to train their abilities. The purpose of

    the study was to clarify which choice of question type the teacher uses to influence interaction

    in the classroom and students' continued knowledge development in mathematics. The

    method used is a systematic literature study with a qualitative approach. Data collection has

    been done through a systematic search of the Web of Science database (WoS).

    The result of the study shows that teachers uses different question types. Exactly what effects

    each question type gives depends on what norms there is in the classroom. There are a few

    question types used in the math classroom which are repeated. Regardless of the question type

    used, nothing seems to impede students' knowledge development in mathematics.

  • 1578.
    Thunell, Robert
    et al.
    Örebro University, School of Science and Technology.
    Östlund, Viktor
    Örebro University, School of Science and Technology.
    GRANSKNINGSPROCESSEN I EN MODELLBASERAD PROJEKTERING - Att utveckla granskningsprocessen av vägmodeller i 3D på ett företag i Örebro2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The development from 2D design to 3D design in the construction industry is something that has been going on for a while. The most common way was earlier to print drawings in 2D, before being delivered to the customer after review. Nowadays it’s becoming more common that the customer doesn’t want any drawings delivered to him, only the 3D model. In large projects is it usually a cheaper design without drawings and if the entrepreneur uses machine control sometimes no drawings are required. The projector only needs to review the 3D model in the 3D program.The purpose of this degree project at WSP (road, street, land) in Örebro was to develop the review process of road models in the program Civil 3D. Together with Skanska, WSP in Örebro (road, street, land) wants to create a higher quality of reviewing and making the work in production easier without any unnecessary problems.The basis of the work is based on literature search on the internet and literature from Örebro University Library, information from WSP and interviews with people working at WSP, Skanska and the Swedish Transport Administration (Trafikverket).This degree project resulted in the following: An improved way of working that is easy to follow  An improved checklist that is short but still content rich  An explanatory template for the checklist that makes it easy to follow  A checklist adapted to the entrepreneurs (Skanska)  Proposals for improvements in the futureThis degree project has developed the review process of road models in Civil 3D at WSP in Örebro (road, street, land). A more extensive work with more entrepreneurs and several offices would be interesting to do.

  • 1579.
    Tincani, Vinicio
    et al.
    University of Pisa, Pisa, Italy.
    Catalano, Manuel
    University of Pisa, Pisa, Italy.
    Grioli, Giorgio
    University of Pisa, Pisa, Italy.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Krug, Robert
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Fantoni, Gualtiero
    University of Pisa, Pisa, Italy.
    Bicchi, Antonio
    University of Pisa, Pisa, Italy; Department of Advanced Robotics, Istituto Italiano di Tecnologia, Genova, Italy.
    Sensitive Active Surfaces on the Velvet II Dexterous Gripper2015Conference paper (Refereed)
  • 1580.
    Tincani, Vinicio
    et al.
    University of Pisa, Pisa, Italy.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Krug, Robert
    Örebro University, School of Science and Technology.
    Catalano, Manuel
    University of Pisa, Pisa, Italy.
    Grioli, Giorgio
    University of Pisa, Pisa, Italy.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Fantoni, Gualtiero
    University of Pisa, Pisa, Italy.
    Bicchi, Antonio
    Istituto Italiano di Tecnologia, Genoa, Italy.
    The Grasp Acquisition Strategy of the Velvet II2015Conference paper (Refereed)
  • 1581.
    Tjus, Emil
    et al.
    Örebro University, School of Science and Technology.
    Gustafsson, Henrik
    Örebro University, School of Science and Technology.
    Fillet optimization on impact piston2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    At Örebro University, a part of the Bachelor of Science in Mechanical Engineering, a degree project of 15 credits is to be made at the end of the education. This project can be performed at the university or at a company, and the purpose is to prepare the student for the upcoming employment after examination. This degree project were performed by Emil Tjus and Henrik Gustafsson during the spring of 2013 at Atlas Copco Rock Drills AB in Örebro on the department of Applied Mechanics.

    The subject of this project was to configure and execute an optimization of a fillet on an impact piston from Atlas Copco Rock Drills AB. The reason to optimize the fillet were founded in the wish to increase the fatigue lifetime of the impact piston.

    The optimization was performed in HyperWorks 12.0, a software that the department of Applied Mechanics not normally uses. This caused finite element models from previous work to be converted and evaluated to ensure that the models were correct configured in HyperWorks.

    The steps that was taken in HyperWorks towards an optimization were done by setting up an approach called Design Of Experiments. The results were then evaluated in the next step, an approach called Fit. After this step, an approach called Optimization were run to generate specific design parameters with the lowest possible stress range of the model. These parameters were then applied to a finite element model and an analysis was made to verify the result from the optimization.

    The results of the optimization lowered the total stress range in a fictitious impact piston from 1146,1 MPa to 717,4 MPa. This result was to be compared with the reference value of 604,7 MPa and the reference impact piston had a simple radial fillet. The result of this project did not yield any improvements of the impact piston. However, an optimization of the fillet was configured and completed in HyperWorks and this can hopefully be at use in future analysis.

  • 1582.
    To, Jimmy
    et al.
    Örebro University, School of Science and Technology.
    Lithell, Mattias
    Örebro University, School of Science and Technology.
    Sigma energy app2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sigma energy app is a mobile application for subscribers to various energy subscriptions. The subscribers can use this mobile application to access information regarding their consumption, invoices and active subscriptions. The mobile application that was built consists of a GUI and a web API as middleman between the application and the database.                     

  • 1583.
    Toivonen, Viktor
    Örebro University, School of Science and Technology.
    Konstruktion av temperaturreglerad kalorimeterkammare2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    It is very difficult to measure switching losses, using electrical measuring instruments,

    especially at high switching frequencies. Calorimetric measuring methods have gained more

    and more attention over the last decade in the area of power loss measurements for switch

    mode power electronics. Calorimeters have been used by chemists for a long time and their

    main benefit is that they can measure the power losses from any object, which is why they are

    so suitable for measuring switching losses. This paper describes the construction of the

    chamber for a calorimeter, designed for measuring 50 to 100 W devices, with a possible

    accuracy of less than 0,2 W. To minimize the power losses through the walls of the chamber,

    their surface temperatures are regulated. The air temperature inside of the chamber is

    regulated as well, to provide it from overheating when heated by the device under test.

    This paper describes, for instance, the calorimeter chamber on a system level, the measuring

    errors related to the chamber as well as how the temperature regulators are designed.

  • 1584.
    Tolboe Handler, Daniel
    et al.
    DTU Compute, Kongens Lyngby, Denmark.
    Hauge, Lotte
    DTU Compute, Kongens Lyngby, Denmark.
    Angelo, Spognardi
    DTU Compute, Kongens Lyngby, Denmark.
    Dragoni, Nicola
    Örebro University, School of Science and Technology.
    Security And Privacy Issues in Healthcare Monitoring Systems: A Case Study2017In: Proceedings of the 10th International Conference on Health Informatics (HEALTHINF'17), SciTePress, 2017Conference paper (Refereed)
  • 1585.
    Tomic, Stevan
    et al.
    Örebro University, School of Science and Technology.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Too cool for school - adding social constraints in human aware planning2014Conference paper (Refereed)
    Abstract [en]

    Robots operating in the presence of humans should adapt their plans and behavior accordingly. The recent area of human-aware planning (HAP) addresses this problem. In this paper, we propose a method for extending HAP to so-called Socially Aware planning. We build on known principles for human context recognition, extending them to support different social situations. In this new paradigm, we are able to define social norms and rules which are taken into account by the planning mechanism to obtain plans consisting of socially adjusted behaviors.

  • 1586.
    Trenkler, Irmin
    Örebro University, School of Science and Technology.
    Managementsystem för livsmedelsindustrin2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes the development of software that I have created for a company in the food industry. This company has created a new product line and required a tool to administer everything from production to shipping. Since the existing software was not suited for this task, a customized solution was developed for this purpose, based on the company's expertise and equipment.

     

    The reader of this report should have a basic understanding of software development and the programming language C#.

  • 1587.
    Triebel, Rudolph
    et al.
    Department of Computer Science, TU, Munich, Germany.
    Arras, Kai
    Social Robotics Lab, University of Freiburg, Freiburg im Breisgau, Germany.
    Alami, Rachid
    LAAS-CNRS: Laboratory for Analysis and Architecture of Systems, Toulouse, France.
    Beyer, Lucas
    RWTH Aachen, Aachen, Germany.
    Breuers, Stefan
    RWTH Aachen, Aachen, Germany.
    Chatila, Raja
    ISIR-CNRS: Institute for Intelligent Systems and Robotics, Paris, France.
    Chetouani, Mohamed
    ISIR-CNRS: Institute for Intelligent Systems and Robotics, Paris, France.
    Cremers, Daniel
    Department of Computer Science, TU, Munich, Germany.
    Evers, Vanessa
    University of Twente, Enschede, Netherlands.
    Fiore, Michelangelo
    LAAS-CNRS: Laboratory for Analysis and Architecture of Systems, Toulouse, France.
    Hung, Hayley
    Delft University of Technology, Delft, Netherlands.
    Ramirez, Omar A. Islas
    ISIR-CNRS: Institute for Intelligent Systems and Robotics, Paris, France.
    Joosse, Michiel
    University of Twente, Enschede, Netherlands.
    Khambhaita, Harmish
    LAAS-CNRS: Laboratory for Analysis and Architecture of Systems, Toulouse, France.
    Kucner, Tomasz
    Leibe, Bastian
    RWTH Aachen, Aachen, Germany.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Linder, Timm
    Social Robotics Lab, University of Freiburg, Freiburg im Breisgau, Germany.
    Lohse, Manja
    University of Twente, Enschede, Netherlands.
    Magnusson, Martin
    Örebro University, School of Science and Technology.
    Okal, Billy
    Social Robotics Lab, University of Freiburg, Freiburg im Breisgau, Germany.
    Palmieri, Luigi
    Social Robotics Lab, University of Freiburg, Freiburg im Breisgau, Germany.
    Rafi, Umer
    RWTH Aachen, Aachen, Germany.
    van Rooij, Marieke
    University of Amsterdam, Amsterdam, Netherlands.
    Zhang, Lu
    University of Twente, Enschede, Netherlands; Delft University of Technology, Delft, Netherlands.
    SPENCER: A Socially Aware Service Robot for Passenger Guidance and Help in Busy Airports2016In: Field and Service Robotics: Results of the 10th International Conference / [ed] David S. Wettergreen, Timothy D. Barfoot, Springer, 2016, 607-622 p.Conference paper (Refereed)
    Abstract [en]

    We present an ample description of a socially compliant mobile robotic platform, which is developed in the EU-funded project SPENCER. The purpose of this robot is to assist, inform and guide passengers in large and busy airports. One particular aim is to bring travellers of connecting flights conveniently and efficiently from their arrival gate to the passport control. The uniqueness of the project stems from the strong demand of service robots for this application with a large potential impact for the aviation industry on one side, and on the other side from the scientific advancements in social robotics, brought forward and achieved in SPENCER. The main contributions of SPENCER are novel methods to perceive, learn, and model human social behavior and to use this knowledge to plan appropriate actions in real-time for mobile platforms. In this paper, we describe how the project advances the fields of detection and tracking of individuals and groups, recognition of human social relations and activities, normative human behavior learning, socially-aware task and motion planning, learning socially annotated maps, and conducting empirical experiments to assess socio-psychological effects of normative robot behaviors.

  • 1588.
    Trincavelli, Marco
    et al.
    Örebro University, School of Science and Technology.
    Coradeschi, Silvia
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Classification of odours for mobile robots using an ensemble of linear classifiers2009In: Olfaction and electronic nose: proceedings of the 13th international symposium on olfaction and electronic nose / [ed] Matteo Pardo, Giorgio Sberveglieri, American Institute of Physics (AIP), 2009, 475-478 p.Conference paper (Refereed)
    Abstract [en]

    This paper investigates the classification of odours using an electronic nose mounted on a mobile robot. The samples are collected as the robot explores the environment. Under such conditions, the sensor response differs from typical three phase sampling processes. In this paper, we focus particularly on the classification problem and how it is influenced by the movement of the robot. To cope with these influences, an algorithm consisting of an ensemble of classifiers is resented. Experimental results show that this algorithm increases classification performance compared to other traditional classification methods.

  • 1589.
    Trincavelli, Marco
    et al.
    Örebro University, School of Science and Technology.
    Coradeschi, Silvia
    Örebro University, Department of Technology.
    Loutfi, Amy
    Örebro University, Department of Technology.
    Classification of odours with mobile robots based on transient response2008In: IEEE/RSJ international conference on intelligent robots and systems, IROS 2008, New York: IEEE , 2008, 4110-4115 p.Conference paper (Refereed)
    Abstract [en]

    Classification of odours with an array of gas sensors mounted on a mobile robot is a challenging and still relatively unexplored topic. Mobile robots able to classify an odour could navigate to a specific source or isolate high concentration areas in applications such as environmental monitoring. A key aspect to classification is to be able to process the data collected while moving the robot and using a simple and compact sensor system. In order to achieve this, we present a classification algorithm that is based in the transient response from the sensors. An analysis of how classification results vary with regards to the movement of the robot is provided and subsequently the experimental validations show that the classification performance depends more on how

    the robot traverses the odour plume and the quality of the transient than on the distance from the source location. The experimental validation has been done in a large unmodified indoor environment.

  • 1590.
    Trincavelli, Marco
    et al.
    Örebro University, School of Science and Technology.
    Hernandez Bennetts, Victor
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    A Least Squares approach for learning gas distribution maps from a set of integral gas concentration measurements obtained with a TDLAS sensor2012In: Proceedings of the IEEE Sensors Conference, 2012, IEEE Sensors Council, 2012, 550-553 p.Conference paper (Refereed)
    Abstract [en]

    Applications related to industrial plant surveillance and environmental monitoring often require the creation of gas distribution maps (GDM). In this paper an approach for creating a gas distribution map using a Tunable Diode Laser Absorption Spectroscopy (TDLAS) sensor and a laser range scanner mounted on a pan tilt unit is presented. The TDLAS sensor can remotely sense the target gas, in this case methane, requiring novel GDM algorithms compared to the ones developed for traditional in-situ chemical sensors. The presented setup makes it possible to create a 3D model of the environment and to calculate the path travelled by the TDLAS beam. The knowledge of the beam path is of crucial importance since a TDLAS sensor provides an integral measurement of the gas concentration over that path. An efficient GDM algorithm based on a quadratic programming formulation is proposed. The approach is tested in an indoor scenario where transparent bottles filled with methane are successfully localized.

  • 1591.
    Trincavelli, Marco
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Feature selection for gas identification with a mobile robot2010In: 2010 IEEE International Conference on Robotics and Automation (ICRA), IEEE conference proceedings, 2010, 2852-2857 p.Conference paper (Other academic)
    Abstract [en]

    In this paper we analyze the problem of discrimination of gases with mobile robots. Previously, it has been shown that the conditions in which data is collected heavily influence the characteristics of the signal to be identified. As a result, the already difficult task of selecting features which characterize a gas is made more challenging by the absence of a steady state response. This is often due to the movement of the robot, and/or the physical properties of the environment, e. g., turbulent airflow creating patches and eddies in the plume. In this work we compare two approaches for feature selection which are able to consider explicitly the information on the experimental setup and optimize the subset of features used in the recognition process. The approaches are tested on a large data set collected with a mobile robot moving in different environments (outdoors and indoors). The results show that the classification performance is improved resulting in a higher average accuracy and lower variance in the accuracy across the different experimental setups.

  • 1592.
    Trincavelli, Marco
    et al.
    Örebro University, School of Science and Technology.
    Monroy, Javier G.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Blanco, Jose Luis
    González-Jimenez, Javier
    Calibration of mox gas sensors in open sampling systems based on gaussian processes2012In: Proceedings of the IEEE Sensors Conference, 2012, IEEE conference proceedings, 2012, 1-4 p.Conference paper (Refereed)
    Abstract [en]

    Calibration of metal oxide (MOX) gas sensor for continuous monitoring is a complex problem due to the highly dynamic characteristics of the gas sensor signal when exposed to natural environment (Open Sampling System - OSS). This work presents a probabilistic approach to the calibration of a MOX gas sensor based on Gaussian Processes (GP). The proposed approach estimates for every sensor measurement a probability distribution of the gas concentration. This enables the calculation of confidence intervals for the predicted concentrations. This is particularly important since exact calibration is hard to obtain due to the chaotic nature that dominates gas dispersal. The proposed approach has been tested with an experimental setup where an array of MOX sensors and a Photo Ionization Detector (PID) are placed downwind w.r.t. the gas source. The PID is used to obtain ground truth concentration. Comparison with standard calibration methods demonstrates the advantage of the proposed approach.

  • 1593.
    Trincavelli, Marco
    et al.
    Örebro University, School of Science and Technology.
    Vergara, A.
    Rulkov, N.
    Murguia, J. S.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Huerta, R.
    Optimizing the operating temperature for an array of MOX sensors on an open sampling system2011In: Olfaction and electronic nose: Proceedings of the 14th international symposium on olfaction and electonic nose, 2011, 225-227 p.Conference paper (Refereed)
    Abstract [en]

    Chemo-resistive transduction is essential for capturing the spatio-temporal structure of chemical compounds dispersed in different environments. Due to gas dispersion mechanisms, namely diffusion, turbulence and advection, the sensors in an open sampling system, i.e. directly exposed to the environment to be monitored, are exposed to low concentrations of gases with many fluctuations making, as a consequence, the identification and monitoring of the gases even more complicated and challenging than in a controlled laboratory setting. Therefore, tuning the value of the operating temperature becomes crucial for successfully identifying and monitoring the pollutant gases, particularly in applications such as exploration of hazardous areas, air pollution monitoring, and search and rescue I. In this study we demonstrate the benefit of optimizing the sensor's operating temperature when the sensors are deployed in an open sampling system, i.e. directly exposed to the environment to be monitored.

  • 1594.
    Tsegaw Tenkir, Woldehana
    Örebro University, School of Science and Technology.
    Urinary Thymine Dimer as a Biomarker for Ultraviolet Radiation Exposure2013Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    The incidence of skin cancer is growing rapidly among peoples of Caucasian origin. Increased exposure to ultraviolet radiation (UVR) from the sun and artificial sources are thought to be the main causative factor for this increase. UVR causes DNA lesions in skin cells, such us thymine dimers (T=T). Studies showed that after skin cells are repaired, T=T is excreted in the urine in significant amounts. The main aim of this study was to evaluate the effect of spending one week in the sunny island of Tenerife on the levels of urinary T=T. In addition the associations with other parameters like UVR dose, serum vitamin D level, pigment protection factor (PPF), erythema of the skin and time spent outdoors were analyzed. Urine and blood samples were collected from 20 participants in Barcelona, Spain, prior to their departure to Tenerife and immediately after return. Urine samples were purified and analyzed by HPLC-coupled 32P-postlabelling method to determine T=T levels and blood samples were used to determine vitamin D levels in serum. UVR exposure was measured using personal dosimeters. The area of skin exposed and time spent outdoors were reported by the participants. The other parameters, which are PPF and erythema of the skin, were also measured before and after the exposure period. Out of the 20 participants, nineteen showed a rise in T=T levels and serum vitamin D levels after the sunny vacation. Although anticipated, no correlation was found between T=T levels and UVR dose which might be due to a limited number of participants. However, several associations were found between the other study variables and an increase in many of the parameters was observed after the vacation. In conclusion we showed that T=T is a sensitive biomarker of exposure to UVR that can be applied in these types of field studies.

  • 1595.
    Törnell, Gustav
    Örebro University, School of Science and Technology.
    Nytt matarkoncept för Atlas Copcos borriggar2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the thesis was to develop a new concept of a feeder for Atlas Copco’s drill rigs. The feeder is placed on a drill rig and is used in example tunnel drilling. At present time, a proven feeder construction is used and improvement work is based of small changes. By daily working with the development of the feeder, there is a risk to get stuck to the design that today’s feeder has. That is why the thesis starting point is to with new eyes look at the problem and develop a new concept for a new feeder. As a first step in the challenge, interviews have been used as a foundation, to get an idea of what today’s problem areas are on the existing feeder. The problem was broken down in to sub problems because a feeder comprises of many parts and functions. When the sub problems were solved a complete solution for the problem was created. In this thesis work a closed construction with all the feeds components enveloped by the feed beam. This could eliminate many flaws on an exposed feed where all the components are exposed to the environment of where the drill rig are working.

  • 1596.
    Törnell, Martin
    Örebro University, School of Science and Technology.
    Konceptframtagning av försvarande multirotor2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The developments in technology are at a furious pace and today you can buy an advanced unmanned aerial vehicle at hobby retail stores. These unmanned aerial vehicles are called multi-rotorcrafts or in the vernacular for drones. These multi-rotorcrafts can deliver a lethal payload with great precision by someone without much technical knowledge. In the urban environment at large public gatherings, it is currently difficult to stop an incoming attack without risking collateral damage. This papers purpose is to highlight the problem and study the technology. As the technology is just becoming more and more advanced you have to be vigilant to prevent a terrorist attack. It may not be enough and then you have to look for other solutions. From the study a number of requirements for a defending solution have been compiled. Also a concept has been developed from the elaborated requirements in shape of a defending multi-rotorcraft.

  • 1597.
    Ullberg, Jonas
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    A customizable approach for monitoring activities of elderly users in their homes2014In: Activity Monitoring by Multiple Distributed Sensing: Second International Workshop, AMMDS 2014, Stockholm, Sweden, August 24, 2014, Revised Selected Papers / [ed] Mazzeo, Pier Luigi and Spagnolo, Paolo and Moeslund, Thomas B., Cham: Springer International Publishing , 2014, 13-25 p.Conference paper (Refereed)
    Abstract [en]

    This paper presents an implemented context recognition system that enables caregivers to query and visualize daily activities of elderly who live in their own homes. The system currently serves several homes across Europe and provides caregivers with the ability to correlate activities with specific health indicators. The system also allows to define conditions under which alarms should be raised.

  • 1598.
    Ullberg, Jonas
    et al.
    Örebro University, School of Science and Technology.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Propagating temporal constraints on sets of intervals2012In: ICAPS Workshop on Planning and Scheduling with Timelines, 2012, 25-32 p.Conference paper (Refereed)
    Abstract [en]

    In this paper we propose a method of propagating quantitative Allen interval constraints on sets of intervals defined by polygons in a two dimensional space. The method is used to solve the problem of inferring timelines of human activities from timelines representing traces of sensor data. The main advantage of this method over others is that it allows a more general description of the events that the intervals are taken to reflect during inference. This paper deals with the algorithmic issues underlying the timeline recognition process. In this context, we compare the performance of our method to that of a state of the art approach based on classical temporal constraint reasoning techniques (Dousson and Maigat, 2007).

  • 1599.
    Vahlstedt, Helene
    Örebro University, School of Science and Technology.
    Matematik på ett andra språk: Om flerspråkiga elevers förståelse av matematiska textuppgifter2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study is to investigate in which ways multilingual students can be supported to understand and make meaning of mathematical word problems. The study is carried out in the form of a systematic review, including 59 studies. The results show that language skills and reading proficiency are important to multilingual students chances to succeed with word problems. That makes it important to adress those issues during mathematics lessons. In many cases students benefit from working with word problems in their first language, but the problem texts can be made more easily comprehensible if they are written in a less complex language. Instruction with the specific aim to teach students how to read and solve word problems seems to be useful. The review shows that the context in word problems also is significant. Students working on word problems are likely to use both their langugages in the cognitive process. That means that both languages may be considered to be resources in the classroom.

  • 1600.
    Vajdi, Amir
    et al.
    Department of Computer Science, University of Massachusetts Boston, Boston, MA, United States.
    Haspel, Nurit
    Department of Computer Science, University of Massachusetts Boston, Boston, MA, United States.
    Banaee, Hadi
    Örebro University, School of Science and Technology.
    A New DP Algorithm for Comparing Gene Expression Data Using Geometric Similarity2015In: Proceedings 2015 IEEE International Conference on Bioinformatics and Biomedicine, New York: IEEE conference proceedings , 2015, 1157-1161 p.Conference paper (Refereed)
    Abstract [en]

    Microarray gene expression data comes as a time series, where the expression level of a gene is recorded at specific time points. Comparing the time series produced by two genes can give us information about the regulatory or inhibitory relationship between the genes. We present a Dynamic Programming (DP) method to compare gene expression data using geometric similarity. We aim to detect similarities and relationships between genes, based on their expression time series. By representing the time series as polygons and compare them, we can find relationships that are not available when the two time series are compared point-by-point. We applied our algorithm on a dataset of 343 regulatory pairs from the alpha dataset and compared them to randomly generated pairs. Using an SVM classifier, we find the optimal similarity score that separates the regulatory dataset from the random pairs. Our results show that we can detect similar pairs better than simple Pearson correlation and we outperform many of the existing methods. This method is an ongoing approach, that can be applied to finding the similarity of any data that can convert to 2D polygon. In the future, we plan to introduce this method as a new classifier.

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