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  • 201.
    Bergman, Malin
    Örebro University, School of Science and Technology.
    Trophic transfer of per- and polyfluoroalkyl substances (PFASs) by glacial relicts in Lake Vättern, Sweden2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The aim with the study was to assess if glacial relict amphipods constitute as vectors of transport of per- and polyfluoroalkyl substances (PFASs) in the Arctic char food web in Lake Vättern, Sweden. Sediment, surface water and biota samples were analysed for PFASs using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), and stable isotope analysis of δ 13C and δ15N was performed on sediments and biota samples. Sediment samples (n=3) were suggested to have PFASs originating from different sources. Generally low concentrations were detected in sediment (sum of all detected PFASs were 2.7 ng/g in St. Aspön, 2.9 ng/g in Visingsö and 0.6 ng/g in Omberg, reported in dry weight), compared to biota and several water samples. The PFAS distribution and concentrations in the samples representing St. Aspön and Visingsö deviated from the third sample from Omberg, which was further evidenced by stable isotope analysis. The average concentration of all detected PFASs in the potentially low contaminated samples was 6 ng/L, while it was 5900 ng/L in the potentially aqueous film forming foam (AFFF) contaminated samples. Surface water samples from Jönköping airport and Kärnebäcken measured concentrations of linear perfluorooctane sulfonate (L-PFOS) that all exceeded the Annual Average Environmental Quality Standard (AA-EQS) value of 0.65 ng/L of PFOS in freshwater (fire pond: 14 000 ng/L, ditch: 600 ng/L, Sandserydsån: 160 ng/L, Kärnebäcken: 150 ng/L). A reference sample that was assumed to represent diffuse sources showed similar distribution of PFASs as in several estuaries around Lake Vättern. Since the surface area of Lake Vättern is large (1900 km2), atmospheric deposition is suggested as one of the major contamination sources. This should be further investigated to better assess the local environmental burden. Trophic magnification factors (TMFs) calculated for L-PFOS, perfluorononaoate (PFNA) and perfluorotridecanoate (PFTrDA) were > 1, indicating biomagnification to higher trophic levels. Among all detected PFASs in biota samples, L-PFOS was the most prominent component (58 %), followed by PFTrDA (20 %), PFNA (6.7 %), perfluoroundecanoate (PFUnDA) (5.3 %), perfluorodecanoate (PFDA) (4.9 %) and perfluorooctanoate (PFOA) (2.9 %). Highest concentrations of all targeted compounds (ΣPFAS 220 ng/g) were detected in Monoporeia, the smallest of amphipods. Contamination profiles of perfluorinated carboxylates (PFCAs) showed similar patterns for several species as those derived in another study from Lake Ontario. Mainly Monoporeia and Pallasea, but partly also Mysis are potential vectors of trophic transport of PFASs in Lake Vättern, although further investigations should be conducted including additional replicates and species. Glacial relict crustaceans are sensitive to pollution in a system, and several fish species 3 in the present study had concentrations of L-PFOS above the AA-EQS value of 9.1 ng/g in fish, thus indicating PFAS contamination. Since many fish species feed on glacial relicts, contamination of these amphipods will transfer PFASs further in the Arctic char food web and could thus affect the whole eco-system in Lake Vättern.

  • 202.
    Bergman, Olivia
    Örebro University, School of Science and Technology.
    Konsten att bestämma π genom slumpen2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med detta arbete var att jämföra olika stokastiska processer som generar π, de olika modellerna som  studerades var modeller baserades på Buffons-, Buffon-Laplaces- och kasta pil-problem och förutom att lösa respektive problem så undersöktes bland annat om det gick att skatta π med motsvarande problem i högre dimensioner.

     

    Innan problemen undersöktes fick läsaren en bakgrund med nödvändiga definitioner och satser inom sannolikhetsteorin, där bland annat Kolmogorovs axiomsystem, fördelningars täthetsfunktion, väntevärde och varians presenterades, men också olika definitioner av konvergens som i sin tur ledde till en sats: Deltametoden, en generalisering av Centrala gränsvärdessatsen. Allt detta tillsammans gjorde det möjligt att lösa problemen och sedan kunna jämföra dem med hjälp av respektive skattnings varians.

     

    Innan problemen undersöktes fick läsaren en bakgrund med nödvändiga definitioner och satser inom sannolikhetsteorin, där bland annat Kolmogorovs axiomsystem, fördelningars täthetsfunktion, väntevärde och varians presenterades, men också olika definitioner av konvergens som i sin tur ledde till en sats: Deltametoden, en generalisering av Centrala gränsvärdessatsen. Allt detta tillsammans gjorde det möjligt att lösa problemen och sedan kunna jämföra dem med hjälp av respektive skattnings varians.

  • 203.
    Bergman-Ärlebäck, Jonas
    et al.
    Linköping University, Linköping, Sweden.
    Blomberg, Per
    Linnaeus University, Växjö, Sweden.
    Nilsson, Per
    Örebro University, School of Science and Technology. Linnaeus University, Växjö, Sweden.
    An instructional design perspective on data-modelling for learning statistics and modelling2015In: Development of mathematics teaching: Design, Scale, Effects: Proceedings of MADIF 9, The Ninth mathematics Education Research Seminar, 2015, p. 37-46Conference paper (Refereed)
    Abstract [en]

    This theoretical and methodological paper discusses the emerging theoretical framing and methodological considerations in our efforts to develop a theoretical approach supporting instructional design for teaching and learning statistics and mathematical modelling. From an instructional design point of view aligned with the goals in governing curricula documents and real classroom constraints, we argue for the integration of the models and modelling perspective on teaching and learning mathematics with a data-modelling approach to facilitate students’ learning statistics and mathematical modelling. An application of the framework is given and future research discussed.

  • 204.
    Bergstedt, Martin
    et al.
    Örebro University, School of Science and Technology.
    Gillström, Tobias
    Örebro University, School of Science and Technology.
    Observator för frontlinjen på surfplatta2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has been carried out at Saab Dynamics. The project's purpose was to develop an application, TBFO, for reporting information containing how the missile GLSDB would strike a target. TBFO is intended to be used in the proximity of the target and information is sent to the planning system GLSDB MPS.

    The application was built around the 3D engine from Vricon and is developed to fit for use of touch devices. The main part of the work concerns the development of user interface for touch input and the system’s application protocol.

    This report describes the processes of developing the system, including what tools and methods that have been used during development. The report also provides an in-depth look at processes used when developing applications for touch devices.

    The conclusion from the results of this project is that the idea of the described system is useful for the process of planning an assault with GLSDB MPS.

  • 205.
    Bergsten, Pontus
    et al.
    Örebro University, School of Science and Technology.
    Palm, Rainer
    Siemens AG Corporate Technology, Otto-Hahn-Ring, Munich, German.
    Driankov, Dimiter
    Örebro University, School of Science and Technology.
    Observers for Takagi-Sugeno fuzzy systems2002In: IEEE transactions on systems, man and cybernetics. Part B. Cybernetics, ISSN 1083-4419, E-ISSN 1941-0492, ISSN 1083-4419/02, Vol. 32, no 1, p. 114-121Article in journal (Refereed)
    Abstract [en]

    We focus on the analysis and design of two different sliding mode observers for dynamic Takagi-Sugeno (TS) fuzzy systems. A nonlinear system of this class is composed of multiple affine local linear models that are smoothly interpolated by weighting functions resulting from a fuzzy partitioning of the state space of a given nonlinear system subject to observation. The Takagi-Sugeno fuzzy system is then an accurate approximation of the original nonlinear system. Our approach to the analysis and design of observers for Takagi-Sugeno fuzzy systems is based on extending sliding mode observer schemes to the case of interpolated multiple local affine linear models. Thus, our main contribution is nonlinear observer analysis and design methods that can effectively deal with model/plant mismatches. Furthermore, we consider the difficult case when the weighting functions in the Takagi-Sugeno fuzzy system depend on the estimated state

  • 206.
    Bergstrand, Simon
    Örebro University, School of Science and Technology.
    Programmering av styrutrustning för vridbord vid radarmätplats2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When calibrating a radars antenna the radar is placed on a turntable that points it to a measuring point on a tower. The main task for the thesis was to write a program in National Instruments programming environment LabVIEW that can turn the turntable with an accuracy of 0.1 milliradians. The program shall be able to be used as a DLL (Dynamic-link library) in LabWindows/CVI where a number of different functions shall be able to control the turntable. Because all of the hardware is from National Instruments the software development became easy. The challenge was instead to measure the lengths and angles of the turntable and at testing be so precise that is necessary. All requirements were met but the lack of accuracy when testing makes the results a bit uncertain.Another part of the thesis was to write documents that specify requirements, interfaces and also describes how the software will be designed, tested and calibrated. For these documents the MIL-STD-498 was used that used to be an American military standard.

  • 207.
    Bergström, Emma
    et al.
    Örebro University, School of Science and Technology.
    Hansson, Sara
    INVERKAN VID VAL AV DRAGSKIVETYP & DRAGSKIVEVINKEL PÅ YT- OCH MATERIALEGENSKAPER AV ETT USKILJNINGSHÄRDBART ROSTFRITT STÅL2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has been designed to get a better understanding of the material and its properties in wire drawing. There have been six different experiments which were conducted with two different drawing angles of three different kinds of drawing dies; regular drawing die, smaller nib and bigger nib. The experiments have been through the beginning of the production where samples have been taken out and then be analyzed in the lab. Results from tensile tests, hardness profile, martensite- and lubrication quantity measurements has been studied and led to the conclusions.

    The conclusion shows that the surface of the wire drawn with the drawing angle 12° had fewer defects than the wire drawn with 18°. Defects that were found on the wire drawn with the bigger nib 18° consisted largely of transverse cracks. Generally the results were similar in all tests for both 12° and 18°, however, the results was diverge on several tests for the smaller

    nib 12° after the drawing die.

  • 208.
    Bergwall, Andreas
    Örebro University, School of Science and Technology.
    A geometric evolution problem2002In: Quarterly of Applied Mathematics, ISSN 0033-569X, E-ISSN 1552-4485, Vol. 60, no 1, p. 37-73Article in journal (Refereed)
    Abstract [en]

    A traditional approach to compression moulding of polymers involves the study of a generalized Hele-Shaw flow of a power-law fluid, and leads to the p-Poisson equation for the instantaneous pressure in the fluid. By studying the convex dual of an equivalent extremal problem, one may let the power-law index of the fluid tend to zero. The solution of the resulting extremal problem, referred to as the asymptotically dual problem, is known to have the property that the flow is always directed towards the closest point on the boundary. In this paper we use this property to introduce the concept of boundary velocity in the case of piecewise C2 domains with only convex corners, and we also give an explicit solution to the asymptotically dual problem in this case. This involves the study of certain topological properties of the ridge of planar domains.With use of the boundary velocity, we define a geometric evolution problem and the concept of classical solutions of it. We prove a uniqueness theorem and use a comparison principle to study the persistence of corners. We actually estimate "waiting times" for corners, in terms of geometric quantities of the initial domain.

  • 209.
    Bergwall, Andreas
    Örebro University, School of Science and Technology.
    A geometric evolution problem arising in an asymptotic approach to compression moulding1998Licentiate thesis, monograph (Other academic)
  • 210.
    Bergwall, Andreas
    Örebro University, School of Science and Technology.
    Conceptualizing reasoning-and-proving opportunities in textbook expositions: Cases from secondary calculus2017In: Proceedings of the Tenth Congress of the European Society for Research in Mathematics Education (CERME10, February 1-5, 2017) / [ed] Dooley, T., & Gueudet, G., Dublin, Ireland: European Society for Research in Mathematics Education , 2017, p. 91-98Conference paper (Refereed)
    Abstract [en]

    Several recent textbook studies focus on opportunities to learn reasoning-and-proving. They typically investigate the extent to which justifications are general proofs and what opportunities exist for learning important elements of mathematical reasoning. In this paper, I discuss how a particular analytical framework for this might be refined. Based on an in-depth analysis of certain textbook passages in upper secondary calculus textbooks, I make an account for analytical issues encountered during this process and identify aspects of reasoning-and-proving in textbooks that might be missed unless the framework is refined. Among them there are characterizations of generality, use of different representations, logical and mathematical structure, and ordering of material and student activities. Finally, implications beyond textbook research are discussed.

  • 211.
    Bergwall, Andreas
    Örebro University, School of Science and Technology.
    On a generality framework for proving tasks2015In: Proceedings of the Ninth Congress of the European Society for Research in Mathematics Education / [ed] Konrad Krainer; Nada Vondrova, Prague: Charles University in Prague, Faculty of Education and ERME , 2015, p. 86-92Conference paper (Refereed)
    Abstract [en]

    In this paper I present an analytic framework for generality in textbook proving tasks that involve functions. The framework is discussed in relation to results obtained when analysing tasks in integral calculus. The results show that the frameworks’ categories are easily distinguishable if the functions are explicitly described. The results are also promising regarding the possibility to clarify differences between textbooks. The analysed sections exemplify that there is not necessarily a correlation between the number of general proving tasks and the opportunities for students to engage in reasoning about arbitrary functions. Limitations and possible refinements of the framework are also discussed.

  • 212.
    Bergwall, Andreas
    et al.
    Örebro University, School of Science and Technology.
    Hemmi, Kirsti
    Åbo Akademi University, Åbo, Finland; Uppsala University, Uppsala, Sweden.
    The State of Proof in Finnish and Swedish Mathematics Textbooks: Capturing Differences in Approaches to Upper-Secondary Integral Calculus2017In: Mathematical Thinking and Learning, ISSN 1098-6065, E-ISSN 1532-7833, Vol. 19, no 1, p. 1-18Article in journal (Refereed)
    Abstract [en]

    Students’ difficulties with proof, scholars’ calls for proof to be a consistent part of K-12 mathematics, and the extensive use of textbooks in mathematics classrooms motivate investigations on how proof-related items are addressed in mathematics textbooks. We contribute to textbook research by focusing on opportunities to learn proof-related reasoning in integral calculus, a key subject in transitioning from secondary to tertiary education. We analyze expository sections and nearly 2000 students’ exercises in the four most frequently used Finnish and Swedish textbook series. Results indicate that Finnish textbooks offer more opportunities for learning proof than do Swedish textbooks. Proofs are also more visible in Finnish text-books than in Swedish materials, but the tasks in the latter reflect a higher variation in nature of proof-related reasoning. Our results are compared with methodologically similar U.S. studies. Consequences for learning and transition to university mathematics, as well as directions for future research, are discussed.

  • 213.
    Bergwall, Andreas
    et al.
    Örebro University, School of Science and Technology.
    Knutsson, Malin
    Örebro University, School of Science and Technology.
    Students’ views on mathematical challenges in working as a teacher2014Conference paper (Refereed)
    Abstract [en]

    Many frameworks for teacher knowledge describe the work of a mathematics teacher as highly complex and therefore requires specialized competences (e.g. Rowland & Ruthven, 2011). At the same time, countries around the world have difficulties in recruiting highly qualified students to teacher education. Furthermore, teacher educators often express that prospective teachers question the amount and level of mathematics that they have to learn. Research on views about teaching often focuses on teachers’ views (Philipp, 2007). Less is known about students’ views about working as a teacher and how those might influence their choice of a profession. The focus of this study is on the views that students have on mathematical challenges associated with the work of a mathematics teacher, when compared to other occupations.

  • 214.
    Berna, Amalia
    et al.
    CSIRO Ecosystem Sciences and CSIRO Food Futures Flagship, Canberra, Australian Capital Territory (ACT), Australia.
    Vergara, Alexander
    University of California, San Diego, USA.
    Trincavelli, Marco
    Örebro University, School of Science and Technology.
    Huerta, Ramon
    University of California, San Diego, USA.
    Afonja, Ayo
    Department of Chemistry, University College London, London, UK.
    Parkin, Ivan
    Binions, Russell
    Trowell, Stephen
    Evaluating zeolite-modified sensors: towards a faster set of chemical sensors2011In: Olfaction and electronic nose: proceedings of the 14th International Symposium on Olfaction and Electronic Nose (ISOEN 2011), May 2-5, 2011, New York City, USA, American Institute of Physics (AIP), 2011, p. 50-52Conference paper (Refereed)
    Abstract [en]

    The response of zeolite-modified sensors, prepared by screen printing layers of chromium titanium oxide (CTO), were compared to unmodified tin oxide sensors using amplitude and transient responses. For transient responses we used a family of features, derived from the exponential moving average (EMA), to characterize chemo-resistive responses. All sensors were tested simultaneously against 20 individual volatile compounds from four chemical groups. The responses of the two types of sensors showed some independence. The zeolite modified CTO sensors discriminated compounds better using either amplitude response or EMA features and CTO-modified sensors also responded three times faster.

  • 215.
    Bernau, Maja
    et al.
    Örebro University, School of Science and Technology.
    Olsson, Tobias
    Örebro University, School of Science and Technology.
    Kundtjänster för mobilapplikationer: Utveckling av rapportgenerator, symbolgenerator,RevitArchitecture–add-in och metadatahantering2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal of this project was to streamline and automate a business system. This was achieved through the implementation of four subtasks. This report describes what parts of the system that needed to be updated and why. It also describes how the development was carried out and what results the project ultimately led to.

     

    The project's tasks were to: Create a report generator designed to generate Excel documents.

    Develop a symbol generator where a user, through a web-based interface, could generate

    symbols. The symbols could then be used in the company's mobile application. Create an

    interface for a web service, and to develop an add-in for the modeling software Revit

    Architecture 2014.

  • 216.
    Bertilsson, Anders
    Örebro University, School of Science and Technology.
    Alternative welding methods for nitrogen alloyed steel2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project explores the feasibility of the solid-state welding method direct-drive friction welding to be used as a joining method for the nitrogen alloyed steel Uddeholm Vanax SuperClean, produced via processes based on powder metallurgy. Vanax SuperClean cannot be welded using fusion welding methods where the base material melts, due to nitrogen escaping the material, resulting in inferior quality welds. The cost of the material motivates the use of Vanax SuperClean for critical parts in applications, combined with a less costly material for the remaining parts, causing alternative joining methods to be examined.

    Vanax SuperClean is friction welded to itself and to Uddeholm steel types Stavax ESR and UHB 11. Samples are prepared for a number of examinations. Microstructures of the samples are examined using microscopy, microhardness testing is carried out per the Vickers principle, retained austenite is measured using X-ray diffraction and tensile testing of the welded samples is performed. Defect-free welds are produced in all examined samples, showing that the method is suitable for Vanax SuperClean and that no preheating or slow cooling of workpieces are necessary.

    The possibility of using friction stir welding as a joining method for Vanax SuperClean is discussed.

  • 217.
    Bertilsson, Jimmy
    et al.
    Örebro University, School of Science and Technology.
    Andersson, Joakim
    Örebro University, School of Science and Technology.
    Ställtidsoptimering2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Emhart Glass Ltd is a world leader in glass bottle manufacturing. They designautomated machines that shape glass bottles. In Sweden there are two factories,one in Örebro and one in Sundsvall. In Örebro they manufacture primarily spareparts and new parts for the machines while they in Sundsvall assemble themachines. There are a total of 15 factories and offices around the world with theheadquarter located in Swiss Cham.Since Emhart Glass Örebro has long setup times on some of their machines. Thisis why we want to identify the current setup process and how the setup processdiffers between operators. We will also look at whether there are anyopportunities for improvement to be made and if they have a standardized way towork. A document that describes how to setup work should be done will also bedeveloped.An excellent tool to shorten the setup time in a production is the SMED method.The philosophy behind SMED is that you should analyze and separate the innerand outer activities. Inner and outer activities mean those activities which canonly be performed when the machine is turned off, respectively those activitiesthat can be performed when the machine is in operation.In order to standardize the adjustment process so that all operators are working ina similar way it's required that you make a documentation about how the workshould be done. Therefore, checklists been developed to the operator. "Checklista- Omställning.xls" is a checklist with the purpose to be able to check which partsof the preparations they have made before the next setup work. It has beendesigned to be easy to keep track of what parts you have done if you had to workwith the machine between the trial or if you quit your shift and leaving parts of thework to the next operator.If all of these improvements are implemented, we expect a set-up time reductionof 20.5% which corresponds to about 35min per set-up. By ignoring the runningtime and only check on the setup times, one can see an improvement of 36.4%.

  • 218.
    Bertilsson, Sabina
    Örebro University, School of Science and Technology.
    Mikroplast i marina livsmedelEn studie om förekomst, risker och överföring mellan trofinivåer2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Cirka 35 tusen ton plast beräknas flyta omkring i haven. Där plastkoncentrationerna ärsom störst antas det bero på havsströmmar, nedskräpning från folktäta kuster menäven fiskeredskap som lämnats kvar eller gått sönder till havs. På grund av UVstrålning,saltvatten och kemiska reaktioner vittrar plastpartiklarna sönder och bildardet som kallas för mikroplast. Avsiktligt tillverkade mikroplaster kan även tillsättastill produkter med olika önskvärda egenskaper, exempelvis som en polerande effekt itandkräm och andra hygienartiklar. De plastpolymerer som återfinns mest i haven ärpolyetylen (PE), polypropylen (PP), polystyren (PS) och polyetylen tereftalat (PET).Man har hittat mikroplaster i olika marina livsmedel såsom som räkor, musslor samtolika matfiskar bland annat torsk men även i livsmedel som havssalt. Det är docksvårt att säga hur dessa mikroplaster kan påverka vår hälsa men konsumerar man fiskoch skaldjur finns det en risk att man också konsumerar mikroplaster. Trots attmikroplaster upp till 5 millimeter med största sannolikhet passerar vårtmatsmältningssystem vid konsumtion, finns det ändå risker då tillsatser iplastpolymererna kan vara hormonstörande och cancerogena.

  • 219.
    Besold, Tarek R.
    et al.
    Institute of Cognitive Science, University of Osnabrück, Osnabrück, Germany.
    Kuehnberger, Kai-Uwe
    Institute of Cognitive Science, University of Osnabrück, Osnabrück, Germany.
    Garcez, Artur d'Avila
    City University London, London, UK.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Fischer, Martin H.
    University of Potsdam, Potsdam, Germany.
    Bundy, Alan
    University of Edinburgh, Edinburgh, UK.
    Anchoring Knowledge in Interaction: Towards a Harmonic Subsymbolic/Symbolic Framework and Architecture of Computational Cognition2015In: Artificial General Intelligence (AGI 2015), Springer, 2015, p. 35-45Conference paper (Refereed)
    Abstract [en]

    We outline a proposal for a research program leading to a new paradigm, architectural framework, and prototypical implementation, for the cognitively inspired anchoring of an agent's learning, knowledge formation, and higher reasoning abilities in real-world interactions: Learning through interaction in real-time in a real environment triggers the incremental accumulation and repair of knowledge that leads to the formation of theories at a higher level of abstraction. The transformations at this higher level filter down and inform the learning process as part of a permanent cycle of learning through experience, higher-order deliberation, theory formation and revision.

    The envisioned framework will provide a precise computational theory, algorithmic descriptions, and an implementation in cyber-physical systems, addressing the lifting of action patterns from the subsymbolic to the symbolic knowledge level, effective methods for theory formation, adaptation, and evolution, the anchoring of knowledge-level objects, realworld interactions and manipulations, and the realization and evaluation of such a system in different scenarios. The expected results can provide new foundations for future agent architectures, multi-agent systems, robotics, and cognitive systems, and can facilitate a deeper understanding of the development and interaction in human-technological settings.

  • 220.
    Bhatt, Mehul
    Örebro University, School of Science and Technology. University of Bremen, Bremen, Germany.
    Cognitive media studies: Potentials for spatial cognition and AI research2018In: Cognitive Processing, ISSN 1612-4782, E-ISSN 1612-4790, Vol. 19, no Suppl. 1, p. S6-S6Article in journal (Other academic)
    Abstract [en]

    Cognitive media studies has developed as an area of research at the interface of disciplines as diverse as aesthetics, psychology, neuroscience, film theory, and cognitive science. In this context, the focus of this talk is on the foundational significance of artificial intelligence and visuo-spatial cognition and computation for the design of inte-grated analytical–empirical methods for the (multi-modal) analysis of human behaviour data vis-a-vis a range of digital visuo-auditory narrative media (e.g., narrative film). The presentation focusses on the methodological foundations and assistive technologies for systematic formalization and empirical analyses aimed at, for instance, the generation of evidence, establishing and characterizing correlates between principles for the synthesis of the moving image (e.g., from a cinematographic viewpoint), and its perceptual recipient effects and influence on observers.

    In the backdrop a range of completed and ongoing experiments, we emphasize the core results on the semantic interpretation of human behaviour vis-a-vis narrative film and its visuo-auditory reception. We demonstrate the manner in which AI-based models for machine coding of narrative, and relational inference and learning serves as basis to externalize explicit and inferred knowledge about embodied visuo-auditory reception, e.g., using modalities such as diagrammatic representations, natural language, complex (dynamic) data visualizations.

    Demonstration: The presentation will particularly showcase methods and tools developed to perform perceptual narrativisation or sensemaking with multi-modal, dynamic human-behaviour data (combining visuo-spatial imagery such as film/video, eye-tracking, head-tracking during a perception task) for a chosen set of experimental material based on existing films, as well as lab-developed experimental content.

  • 221.
    Bhatt, Mehul
    Örebro University, School of Science and Technology. University of Bremen, Bremen, Germany.
    Embodied architecture design: On people-centered design of visuo-locomotive cognitive experiences2018In: Cognitive Processing, ISSN 1612-4782, E-ISSN 1612-4790, Vol. 19, no Suppl. 1, p. S5-S5Article in journal (Other academic)
    Abstract [en]

    This presentation focusses on the analysis and design of human-centered, embodied, cognitive user experiences from the perspectives of spatial cognition and computation, artificial intelligence, and human-computer interaction research. Focusing on large-scale built up spaces (in particular hospitals), this presentation will particularly address:

    ‘how can human-centered cognitive modalities of visuo-locomotive perception constitute the foundational building blocks of design education, discourse, systems, and the professional practice of spatial design for architecture’.

    The presentation will emphasizeevidence-based multimodality studies from the viewpoints of visuo-locomotive (i.e., pertaining to vision, movement, and wayfinding) cognitive experiences. Modalities being investigated include: (1) visual attention (by eye-tracking), gesture, language, facial expressions; (2) human expert guided event segmentation (e.g., coming from behavioral or environmental psychologists, designers, annotators); (3) deep analysis based on dialogic components, think-aloud protocols. We demonstrate (1–3) in the context of a large-scale study conducted at the Old and New Parkland Hospitals in Dallas, Texas.

    This research (and symposium) calls for a tightly integrated approach combining analytical methods (rooted in AI and computational cognition) and empirical methods (rooted in psychology and perception studies) for developing human-centered architectural design technologies, and technology-mediated (architectural) design synthesis.

  • 222.
    Bhatt, Mehul
    Örebro University, School of Science and Technology. University of Bremen, Bremen, Germany.
    Minds. Movement. Moving image2018In: Cognitive Processing, ISSN 1612-4782, E-ISSN 1612-4790, Vol. 19, no Suppl. 1, p. S5-S5Article in journal (Other academic)
    Abstract [en]

    This symposium—conducted in two parts—explores the confluence of empirically-based qualitative research in the cognitive and psychological sciences (focusing on visual and spatial cognition) with computationally-driven analytical methods (rooted in artificial intelligence) in the service of communications, media, design, and human behavioural studies. With a focus on architecture and visuo-auditory media design, the twin-symposia will demonstrate recent results and explore the synergy of research methods for the study of human behaviour in the chosen (design) contexts of socio-cultural, and socio-technological significance.

    The symposium brings together experts and addresses methodsand perspectives from:

    •  Visuo-Spatial Cognition and Computation

    •  Artificial Intelligence, Cognitive Systems

    •  Multimodality and Interaction

    •  Cognitive Science and Psychology

    •  Neuroscience

    •  Design Cognition and Computation

    •  Communications and Media Studies

    •  Architecture, Built Environment

    •  Design Studies (focus on architecture and visuo-auditory media)

    •  Evidence Based Design

    The symposium particularly emphasises the role of multimodality and mediated interaction for the analysis and design of human-centered, embodied, cognitive user experiences in everyday life and work. Here, the focus is on multimodality studies aimed at the semantic interpretation of human behaviour, and the empirically-driven synthesis of embodied interactive experiences in real world settings. In focus are narrative media design, architecture and built environment design, product design, cognitive media studies (film, animation, VR, sound and music design), and user interaction studies. In these contexts, the symposium emphasizes evidence-based multimodality studies from the viewpoints of visual (e.g.,attention and recipient effects), visuo-locomotive (e.g. , movement, wayfinding), and visuo-auditory (e.g., narrative media) cognitive experiences. Modalities being investigated include, but are not limited to:

    •  visual attention (by eye-tracking), gesture, speech, language, facial expressions, tactile interactions, olfaction, biosignals;

    •  human expert guided event segmentation (e.g. coming from behavioral or environmental psychologists, designers, annotators,crowd-sensing)

    •  deep analysis based on dialogic components, think-aloud protocols

    The scientific agenda of the twin-symposia also emphasizes the multi-modality of the embodied visuo-spatial thinking involved in ‘‘problem-solving’’ for the design of objects, artefacts, and inter-active people-experiences emanating there from. Universality andinclusion in ‘‘design thinking’’ are of overarching focus in all design contexts relevant to the symposium; here, the implications of mul-timodality studies for inclusive design, e.g.,creation of presentations of the same content in different modalities, are also of interest. The symposium provides a platform to discuss the development of next-generation embodied interaction design systems, practices, and (human-centered) assistive frameworks and technologies encompassing the multi-faceted nature of embodied design conception and synthesis. Individual contributions/talks within the two symposia address the themes under consideration from formal, computational, cognitive, design, engineering, empirical, and philosophical perspectives.

  • 223.
    Bhatt, Mehul
    et al.
    Örebro University, School of Science and Technology. Human-Centred Cognitive Assistance Lab. (HCC), University of Bremen, Bremen, Germany.
    Cutting, James
    Cornell University, Ithaca, USA.
    Levin, Daniel
    Department of Psychology and Human Development, Vanderbilt University, Nashville, USA.
    Lewis, Clayton
    University of Colorado, Boulder, USA.
    Cognition, Interaction, Design: Discussions as Part of the Codesign Roundtable 20172017In: Künstliche Intelligenz, ISSN 0933-1875, E-ISSN 1610-1987, Vol. 31, no 4, p. 363-371Article in journal (Refereed)
    Abstract [en]

    This transcript documents select parts of discus-sions on the confluence of cognition, interaction, design, and human behaviour studies. The interview and related events were held as part of the CoDesign 2017 Roundtable (Bhatt in CoDesign 2017—The Bremen Summer of Cognition and Design/CoDesign Roundtable. University of Bremen, Bremen, 2017) at the University of Bremen (Germany) in June 2017. The Q/A sessions were moderated by Mehul Bhatt (University of Bremen, Germany., and Örebro Uni-versity, Sweden) and Daniel Levin (Vanderbilt University, USA). Daniel Levin served in a dual role: as co-moderator of the discussion, as well as interviewee. The transcript is published as part of a KI Journal special issue on “Seman-tic Interpretation of Multi-Modal Human Behaviour Data” (Bhatt and Kersting in Special Issue on: Semantic Interpre-tation of Multimodal Human Behaviour Data, Artif Intell, 2017).

  • 224.
    Bhatt, Mehul
    et al.
    Örebro University, School of Science and Technology. Human-Centred Cognitive Assistance Lab. (HCC), University of Bremen, Bremen, Germany.
    Kersting, Kristian
    Technical University of Dortmund (DE), Dortmund, Germany.
    Semantic Interpretation of Multi-Modal Human-Behaviour Data: Making Sense of Events, Activities, Processes2017In: Künstliche Intelligenz, ISSN 0933-1875, E-ISSN 1610-1987, Vol. 31, no 4, p. 317-320Article in journal (Refereed)
    Abstract [en]

    This special issue presents interdisciplinary research—at the interface of artificial intelligence, cogni-tive science, and human-computer interaction—focussing on the semantic interpretation of human behaviour. The special issue constitutes an attempt to highlight and steer founda-tional methods research in artificial intelligence, in particular knowledge representation and reasoning, for the develop-ment of human-centred cognitive assistive technologies. Of specific interest and focus have been application outlets for basic research in knowledge representation and reason-ing and computer vision for the cognitive, behavioural, and social sciences.

  • 225.
    Bhatt, Mehul
    et al.
    Örebro University, School of Science and Technology. Cognitive Systems, University of Bremen, Bremen, Germany; Sonderforschungsbereich Transregional Collaborative Research Center 8, Spatial Cognition, University of Bremen, Bremen, Germany.
    Suchan, Jakob
    Cognitive Systems, University of Bremen, Bremen, Germany; Sonderforschungsbereich Transregional Collaborative Research Center 8, Spatial Cognition, University of Bremen, Bremen, Germany.
    Schultz, Carl
    Cognitive Systems, University of Bremen, Bremen, Germany; Sonderforschungsbereich Transregional Collaborative Research Center 8, Spatial Cognition, University of Bremen, Bremen, Germany.
    Cognitive Interpretation of Everyday Activities - Toward Perceptual Narrative Based Visuo-Spatial Scene Interpretation2013In: 2013 Workshop on Computational Models of Narrative / [ed] Mark A. Finlayson; Bernhard Fisseni; Benedikt Löwe; Jan Christoph Meister, Schloss Dagstuhl - Leibniz-Zentrum für Informatik , 2013, Vol. 32, p. 24-29Conference paper (Refereed)
    Abstract [en]

    We position a narrative-centred computational model for high-level knowledge representation and reasoning in the context of a range of assistive technologies concerned with visuo-spatial perception and cognition tasks. Our proposed narrative model encompasses aspects such as space, events, actions, change, and interaction from the viewpoint of commonsense reasoning and learning in large-scale cognitive systems. The broad focus of this paper is on the domain of human-activity interpretation in smart environments, ambient intelligence etc. In the backdrop of a smart meeting cinematography domain, we position the proposed narrative model, preliminary work on perceptual narrativisation, and the immediate outlook on constructing general-purpose open-source tools for perceptual narrativisation.

  • 226. Bidot, Julien
    et al.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Lagriffoul, Fabien
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Geometric backtracking for combined task and motion planning in robotic systems2017In: Artificial Intelligence, ISSN 0004-3702, E-ISSN 1872-7921, Vol. 247, p. 229-265Article in journal (Refereed)
    Abstract [en]

    Planners for real robotic systems should not only reason about abstract actions, but also about aspects related to physical execution such as kinematics and geometry. We present an approach to hybrid task and motion planning, in which state-based forward-chaining task planning is tightly coupled with motion planning and other forms of geometric reasoning. Our approach is centered around the problem of geometric backtracking that arises in hybrid task and motion planning: in order to satisfy the geometric preconditions of the current action, a planner may need to reconsider geometric choices, such as grasps and poses, that were made for previous actions. Geometric backtracking is a necessary condition for completeness, but it may lead to a dramatic computational explosion due to the large size of the space of geometric states. We explore two avenues to deal with this issue: the use of heuristics based on different geometric conditions to guide the search, and the use of geometric constraints to prune the search space. We empirically evaluate these different approaches, and demonstrate that they improve the performance of hybrid task and motion planning. We demonstrate our hybrid planning approach in two domains: a real, humanoid robotic platform, the DLR Justin robot, performing object manipulation tasks; and a simulated autonomous forklift operating in a warehouse.

  • 227.
    Bidot, Julien
    et al.
    Örebro University, School of Science and Technology.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Lagriffoul, Fabien
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Geometric backtracking for combined task and path planning in robotic systemsManuscript (preprint) (Other academic)
    Abstract [en]

    Planners for real, possibly complex, robotic systems should not only reason about abstract actions, but also about aspects related to physical execution such as kinematics and geometry. We present an approach in which state-based forward-chaining task planning is tightly coupled with sampling-based motion planning and other forms of geometric reasoning. We focus on the problem of geometric backtracking which arises when a planner needs to reconsider geometric choices, like grasps and poses, that were made for previous actions, in order to satisfy geometric preconditions of the current action. Geometric backtracking is a necessary condition for completeness, but it may lead to a dramatic computational explosion due to the systematic exploration of the space of geometric states. In order to deal with that, we introduce heuristics based on the collisions between the robot and movable objects detected during geometric backtracking and on kinematic relations between actions. We also present a complementary approach based on propagating explicit constraints which are automatically generated from the symbolic actions to be evaluated and from the kinematic model of the robot. We empirically evaluate these dierent approaches. We demonstrate our planner on a real advanced robot, the DLR Justin robot, and on a simulated autonomous forklift. 

  • 228.
    Bimer, Hampus
    et al.
    Örebro University, School of Science and Technology.
    Stenmark, Jonas
    Örebro University, School of Science and Technology.
    Optimering av produktionslinje för att reducera ledtiden: En fallstudie på Seco Tools AB i Arboga2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This case study has been carried out at the Seco Tools factory in Arboga. Seco Tools is one of the world's largest providers of comprehensive metal cutting solutions for milling, turning, holemaking and tooling systems. The majority of the Arboga factory are at the front edge with continuous improvements. However, since a time back problems have occurred with one of their manufacturing lines. The problem that Seco Tools considers to have with the line is the long lead time and the current layout is far from optimal.

    The purpose of this case study was to make a mapping of the process and then analyze and make suggestions on how the process could be more effective with considerations of reducing lead time. The proposals have been made by empirical data collection through interviews with employees as well as observations in production. The information obtained has been studied and analyzed using several theories and tools, and thereafter suggestions have been made for improvements. Five proposals for different alternative layouts have been made, but also more general improvement proposals have been put forward to accomplish a positive impact on the lead time of the process. These proposals will serve as a supporting basis for Seco Tools in their continued efforts to improve the process.

  • 229. Birk, Andreas
    et al.
    Poppinga, Jann
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Nevatia, Yashodhan
    Planetary Exploration in USARSim: A Case Study including Real World Data from Mars2009In: RoboCup 2008: Robot Soccer World Cup XII / [ed] Volume editors: Luca Iocchi, Hitoshi Matsubara, Alfredo Weitzenfeld, Changjiu Zhou, Springer Berlin Heidelberg , 2009, p. 463-472Conference paper (Refereed)
    Abstract [en]

     Intelligent Mobile Robots are increasingly used in unstructured domains; one particularly challenging example for this is, planetary exploration. The preparation of according missions is highly non-trivial, especially as it is difficult to carry out realistic experiments without, very sophisticated infrastructures. In this paper, we argue that, the, Unified System for Automation and Robot Simulation (USARSim) offers interesting opportunities for research on planetary exploration by mobile robots. With the example of work on terrain classification, it, is shown how synthetic as well as real world data, from Mars call be used to test an algorithm's performance in USARSim. Concretely, experiments with an algorithm for the detection of negotiable ground oil a, planetary surface are presented. It is shown that the approach performs fast; and robust on planetary surfaces.

  • 230. Birk, Andreas
    et al.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Nevatia, Yashodhan
    Ambrus, Rares
    Poppinga, Jan
    Pathak, Kaustubh
    Terrain Classification for Autonomous Robot Mobility: from Safety, Security Rescue Robotics to Planetary Exploration2008Conference paper (Refereed)
  • 231.
    Biro, Alexander
    Örebro University, School of Science and Technology.
    Combining adjustable autonomy and shared control as a new platform for controlling robotic systems with ROS on TurtleBot2018Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Fully autonomous robotic systems can fulfill their functionality, without human interaction, but their efficiency is way lower, than a robotic system, which is teleoperated by a specialist. The teleoperation of robotic systems requires  continuously high attention from the operator, if this attention is taken away or reduced, the efficiency drops heavily. The combination of Adjustable Autonomy and Shared Control represent a promising approach, of how great efficiency could be maintained in a robotic system, with a minimum of human interaction.

     

    The goal of this project is the re-implementation of the utilitarian voting scheme for navigation for usage with modern robotic platforms, as proposed in the publication "Experiments in Adjustable Autonomy" by Jacob W. Crandall and Michael A. Goodrich. This voting scheme combines a proposed direction, which is given by a human operator, with environmental sensor data to determine the best direction for a robots next movement.

     

    The implemented prototype in this project was developed with ROS on TurtleBot and is processing the sensor data and calculating the best direction for the robot's movement in the same way, as the original prototype. Since the original setup consists of a Nomad SuperScout robot with sixteen sonar range finders, adjustments needed to be made, to run the same algorithm on a different setup. The  correct processing of the input data and estimation of the best direction was verified by pen and paper calculations. Finally, further ideas for improving the implemented prototype and usage in other scenarios were presented.

  • 232.
    Bjuhr, Jessica
    et al.
    Örebro University, School of Science and Technology.
    Jansson, Maria
    Örebro University, School of Science and Technology.
    Förstudie kring verktyg för DCN registrering/uppföljning2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work has been performed on a department that works with preparation for new products. They are in charge of coordinating several different units during these preparations. In the current situation, this process does not work optimally. There is no common approach to monitoring and documentation of the process which leads to difficulties in the interaction between the units. Problems have also arisen when the product has been put into production. The company is also working with the ISO 9001 and 14001, which requires documentation and monitoring of the process.

    The aim of the project is to present the basic steps for a new approach for documentation and monitoring in this process from a case study. Interviews with employees in the process have been conducted to gather information about the current approach. In addition, literary studies and benchmarking have been used as methods.

    Based on this, improvement proposals for the work of documentation and monitoring have been developed. The proposals may also contribute to increased understanding of the process and improved collaboration between the employees. However, this is not something that can be guaranteed. The improvement proposals should be seen just as a suggestion for improvement and not hindsight on how the work should be designed in the process.

  • 233.
    Bjureland, Sofie
    et al.
    Örebro University, School of Science and Technology.
    Lagré, Daniel
    Örebro University, School of Science and Technology.
    Problemlösning - en systematisk litteraturstudie över undervisningsmetoder som främjar elevers problemlösningsförmåga2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This systematic review aims to present teaching methods that research show enhances students´ problem solving skills. The review is completed by an analysis of 66 international articles. The analysis resulted in an identification of nine teaching methods. The overall result of the study shows that the nine teaching methods all enhances students’ problem solving skills. The results also suggest that the single most important factor to enhance students´ problem solving skills is the implementation of a specific teaching method. Consequences for education and future research are discussed.

  • 234.
    Bjurlid, Filip
    Örebro University, School of Science and Technology.
    Polybrominated dibenzo-p-dioxins and furans: from source of emission to human exposure2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Brominated flame retardants (BFRs), which are ubiquitous in modern life and the environment, are the major source for polybrominated dibenzo-p-dioxins and furans (PBDD/Fs). The knowledge about PBDD/Fs is lim-ited compared to other environmental pollutants, even though PBDD/Fs show similar toxicity as polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) which are considered to be among the most toxic man-made substances. The aim of the thesis was to provide a better understanding of PBDD/Fs by investigating the occurrence and distribution of PBDD/Fs in the following matrices: soot and gas from an accidental fire site which is a typical source of emission, blubber from marine mammals living in both far remote areas as well as areas close to anthropogenic sources, and finally in human milk from ten nursing mothers.

    PBDD/Fs was detected in blubber from pilot whales sampled around Faroe Islands, which proved the occurrence in marine mammals in a far remote area. The findings of PBDD/Fs in blubber from Baltic ringed seals showed slightly higher concentrations compared to the pilot whales, which is expected since the Baltic Sea in among the world’s most contam-inated water areas. In the pilot whales and the ringed seals, the average contribution from PBDD/Fs to the total (PCDD/F+PBDD/F) Total Equiv-alent Quantity (TEQ) was low, (1-8%). In gas and soot samples from the accidental fire site, PBDD/Fs were detected in all samples and the contri-bution of PBDD/Fs to the total TEQ was close to 100%. In the human milk samples, PBDD/Fs were detected in all samples and the average con-tribution of PBDD/Fs to the total TEQ was 40%. The results indicate that PBDD/Fs are of concern for human exposure, and should be monitored together with PCDD/Fs in future studies. Moreover, the occurrence at ac-cidental fire sites indicate that PBDD/Fs are a source for occupational ex-posure for firefighters and other professionals. The impact from PBDD/Fs on marine mammalians seems to be of less concern.

    List of papers
    1. Occurrence of brominated dioxins in a study using various firefighting methods
    Open this publication in new window or tab >>Occurrence of brominated dioxins in a study using various firefighting methods
    2017 (English)In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 599-600, p. 1213-1221Article in journal (Refereed) Published
    Abstract [en]

    The use of different firefighting methods influences how fast a fire is extinguished and how fast the temperature drops in the area affected by the fire. These differences may also influence the formation of harmful pollutants during firefighting of an accidental fire. The aim was to study occurrence of brominated dibenzo-p-dioxins and furans (PBDD/Fs) in gas and soot during five fire scenarios resembling a small apartment fire and where different firefighting methods were used. Samples of gas and soot were taken both during the buildup of the fire and during the subsequent extinguishing of the fire while using different firefighting methods (nozzle, compressed air foam system, cutting extinguisher) and an extinguishing additive. New containers equipped with identical sets of combustible material were used for the five tests. The use of different firefighting methods and extinguishing additive induced variations in concentration and congener profiles of detected PBDD/Fs. The concentration range of Sigma PBDD/Fs in gas was 4020-18,700 pg/m(3), and in soot 76-4092 pg/m(2). PBDFs were the predominant congeners and 1,2,3,4,6,7,8-HpBDF was the most abundant congener. Chlorinated dibenzo-p-dioxins and furans (PCDD/Fs) were also monitored. The PBDD/Fs contributed with in average 97% to the total (PCDD/Fs plus PBDD/Fs) toxic equivalents, in soot and gas. During extinguishing, the shorter time the temperature was around 300 degrees C, the lower occurrence of PBDD/Fs. In the study the firefighting methods showed a difference in how effectively they induced a temperature decrease below 300 degrees C in the fire zone during quenching, where cutting extinguishing using additive and the compressed air foam system showed the fastest drop in temperature.

    Place, publisher, year, edition, pages
    Elsevier, 2017
    Keywords
    PBDD/F, PCDD/F, Fire, Cutting extinguisher, Foam, Additive, Nozzle, Formation
    National Category
    Environmental Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-59123 (URN)10.1016/j.scitotenv.2017.05.087 (DOI)000405253500018 ()28514839 (PubMedID)2-s2.0-85019068316 (Scopus ID)
    Funder
    Swedish Civil Contingencies Agency
    Available from: 2017-08-22 Created: 2017-08-22 Last updated: 2018-09-04Bibliographically approved
    2. Occurrence of polybrominated dibenzo-p-dioxins, dibenzofurans (PBDD/Fs) and polybrominated diphenyl ethers (PBDEs) in pilot whales (Globicephala melas) caught around the Faroe Islands
    Open this publication in new window or tab >>Occurrence of polybrominated dibenzo-p-dioxins, dibenzofurans (PBDD/Fs) and polybrominated diphenyl ethers (PBDEs) in pilot whales (Globicephala melas) caught around the Faroe Islands
    2018 (English)In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 195, p. 11-20Article in journal (Refereed) Published
    Abstract [en]

    Blubber from Faroese pilot whales (Globicephala melas) was analysed for brominated dioxins PBDD/Fs, with a subset also analysed for chlorinated dioxins, PCDD/Fs. The studied individuals were restricted to juvenile male whales sampled in the Faroe Islands during the period 1997–2013. Among the PBDD/Fs, the furans were predominant, although the relative abundance of various congeners differed between samples. Furans accounted for, on average, 79% of the ∑PBDD/Fs in the samples, with 1,2,3,4,6,7,8-HpBDF the most abundant congener, found in half of the analysed pilot whales. The concentration range for ∑PBDD/Fs among the samples was 0.080–71 pg/g l.w. (lipid weight), and the sum of toxic equivalents ranged from 0.0039 to 4.7 pg TEQ/g l.w. No relationship was found between PBDD/Fs and PCDD/Fs. In addition, 20 pilot whale samples from the period 2010–2013 were analysed for PBDEs. Several PBDE congeners were found in all of the sampled pilot whales, and at noticeably higher levels than PBDD/Fs and PCDD/Fs. The ∑PBDEs ranged from 140 to 1900 ng/g l.w., with BDE #47 the most abundant congener detected in the samples. Results from the present study were then compared with data from previous studies on pilot wales to investigate temporal trends between 1986 and 2013. The comparison indicated that PBDE concentrations in juvenile males have decreased from 1996 to the latest observations in 2013. No relationship between the concentration levels of PBDD/Fs and PBDEs in the sampled pilot whales could be identified, which indicates possible differences in the metabolism of, or exposure to, PBDEs and PBDD/Fs.

    Place, publisher, year, edition, pages
    Elsevier, 2018
    Keywords
    PBDD/Fs, PBDEs, PCDD/Fs, Pilot whale blubber, Faroe Islands
    National Category
    Other Chemistry Topics Environmental Sciences
    Identifiers
    urn:nbn:se:oru:diva-63414 (URN)10.1016/j.chemosphere.2017.12.044 (DOI)000424172400002 ()29248748 (PubMedID)2-s2.0-85037990841 (Scopus ID)
    Note

    Funding Agency:

    Danish Environmental Protection Agency as part of the environmental support program Dancea - Danish Cooperation for Environment in the Arctic

    Available from: 2017-12-18 Created: 2017-12-18 Last updated: 2018-08-16Bibliographically approved
    3. Temporal trends of PBDD/Fs, PCDD/Fs, PBDEs and PCBs in ringed seals from the Baltic Sea (Pusa hispida botnica) between 1974 and 2015
    Open this publication in new window or tab >>Temporal trends of PBDD/Fs, PCDD/Fs, PBDEs and PCBs in ringed seals from the Baltic Sea (Pusa hispida botnica) between 1974 and 2015
    2018 (English)In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 616-617, p. 1374-1383Article in journal (Refereed) Published
    Abstract [en]

    Temporal trends in exposure to persistent organic pollutants (POPs) were assessed in 22 pooled samples gathered from 69 individuals of Baltic ringed seal (Pusa hispida botnica) from 1974 to 2015. Samples were analysed for polybrominated dibenzo-p-dioxins and furans (PBDD/Fs), polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs). No previous study has reported on the occurrence of PBDD/Fs in marine mammals in the Baltic Sea. Concentrations of pollutants in Baltic ringed seal, a marine mammal and top predator, can be used as an indicator of pollutants concentrations in the Baltic region.

    Visual inspection of data did not show any temporal trends for PBDD/Fs, while the PCDD/Fs and PCBs showed decreasing concentrations between 1974 and 2015. PBDEs increased until the end of the 1990s and then decreased until the end of the period. ∑ PBDD/Fs ranged from 0.5–52.3 pg/g lipid weight (l.w.) (0.08–4.8 pg TEQ/g l.w.), with 1,2,3,4,6,7,8-HpBDF contributing on average 61% to ∑ PBDD/Fs. ∑ PCDD/Fs ranged from 103 to 1480 pg/g l.w. (39–784 pg TEQ/g l.w.), with 1,2,3,6,7,8-HxCDD, 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDF showing the highest average concentrations. PBDD/F toxic equivalents (TEQ) contributed on average 1.1% to the total (PBDD/F + PCDD/F) TEQ. The ∑ PBDEs concentration range was 18.7–503 ng/g l.w., with BDE #47 the predominant congener. The concentration range for ∑ PCBs was 2.8–40.1 μg/g l.w., with #138 and #153 the most abundant congeners. Visual inspection of the data showed decreasing concentrations for all compound groups except PBDD/Fs. A slight increase in the PBDD/Fs concentrations was observed from 2004 onwards. This observation needs to be investigated further.

    Place, publisher, year, edition, pages
    Elsevier, 2018
    Keywords
    Dioxins, Furans, POPs, Marine mammal
    National Category
    Other Chemistry Topics Environmental Sciences
    Identifiers
    urn:nbn:se:oru:diva-63413 (URN)10.1016/j.scitotenv.2017.10.178 (DOI)000424121800137 ()29066193 (PubMedID)2-s2.0-85038955003 (Scopus ID)
    Note

    Funding Agency:

    Swedish Environmental Protection Agency  2213-15-022

    Available from: 2017-12-18 Created: 2017-12-18 Last updated: 2018-08-16Bibliographically approved
    4. Polybrominated dibenzo-p-dioxins and dibenzofurans and Stockholm Convention POPs in human milk: evaluation of the effects of breastfeeding duration
    Open this publication in new window or tab >>Polybrominated dibenzo-p-dioxins and dibenzofurans and Stockholm Convention POPs in human milk: evaluation of the effects of breastfeeding duration
    (English)Manuscript (preprint) (Other academic)
    National Category
    Other Chemistry Topics
    Identifiers
    urn:nbn:se:oru:diva-63415 (URN)
    Available from: 2017-12-18 Created: 2017-12-18 Last updated: 2017-12-18Bibliographically approved
  • 235.
    Bjurlid, Filip
    et al.
    Örebro University, School of Science and Technology.
    Dam, Maria
    Faroe Islands' Environment Agency, Argir, Denmark.
    Hoydal, Katrin
    Faroe Islands' Environment Agency, Argir, Denmark.
    Hagberg, Jessika
    Örebro University, School of Science and Technology. Department of Occupational and Environmental Medicine, Faculty of Health and Medical Sciences, Örebro University, Örebro, Sweden.
    Occurrence of polybrominated dibenzo-p-dioxins, dibenzofurans (PBDD/Fs) and polybrominated diphenyl ethers (PBDEs) in pilot whales (Globicephala melas) caught around the Faroe Islands2018In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 195, p. 11-20Article in journal (Refereed)
    Abstract [en]

    Blubber from Faroese pilot whales (Globicephala melas) was analysed for brominated dioxins PBDD/Fs, with a subset also analysed for chlorinated dioxins, PCDD/Fs. The studied individuals were restricted to juvenile male whales sampled in the Faroe Islands during the period 1997–2013. Among the PBDD/Fs, the furans were predominant, although the relative abundance of various congeners differed between samples. Furans accounted for, on average, 79% of the ∑PBDD/Fs in the samples, with 1,2,3,4,6,7,8-HpBDF the most abundant congener, found in half of the analysed pilot whales. The concentration range for ∑PBDD/Fs among the samples was 0.080–71 pg/g l.w. (lipid weight), and the sum of toxic equivalents ranged from 0.0039 to 4.7 pg TEQ/g l.w. No relationship was found between PBDD/Fs and PCDD/Fs. In addition, 20 pilot whale samples from the period 2010–2013 were analysed for PBDEs. Several PBDE congeners were found in all of the sampled pilot whales, and at noticeably higher levels than PBDD/Fs and PCDD/Fs. The ∑PBDEs ranged from 140 to 1900 ng/g l.w., with BDE #47 the most abundant congener detected in the samples. Results from the present study were then compared with data from previous studies on pilot wales to investigate temporal trends between 1986 and 2013. The comparison indicated that PBDE concentrations in juvenile males have decreased from 1996 to the latest observations in 2013. No relationship between the concentration levels of PBDD/Fs and PBDEs in the sampled pilot whales could be identified, which indicates possible differences in the metabolism of, or exposure to, PBDEs and PBDD/Fs.

  • 236.
    Bjurlid, Filip
    et al.
    Örebro University, School of Science and Technology.
    Hagberg, Jessika
    Örebro University, School of Science and Technology. Department of Occupational and Environmental Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Polybrominated dibenzo-p-dioxins and dibenzofurans and Stockholm Convention POPs in human milk: evaluation of the effects of breastfeeding durationManuscript (preprint) (Other academic)
  • 237.
    Bjurlid, Filip
    et al.
    Örebro University, School of Science and Technology.
    Kärrman, Anna
    Örebro University, School of Science and Technology.
    Ricklund, Niklas
    Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro, Sweden.
    Hagberg, Jessika
    Örebro University, School of Science and Technology. Department of Occupational and Environmental Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Occurrence of brominated dioxins in a study using various firefighting methods2017In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 599-600, p. 1213-1221Article in journal (Refereed)
    Abstract [en]

    The use of different firefighting methods influences how fast a fire is extinguished and how fast the temperature drops in the area affected by the fire. These differences may also influence the formation of harmful pollutants during firefighting of an accidental fire. The aim was to study occurrence of brominated dibenzo-p-dioxins and furans (PBDD/Fs) in gas and soot during five fire scenarios resembling a small apartment fire and where different firefighting methods were used. Samples of gas and soot were taken both during the buildup of the fire and during the subsequent extinguishing of the fire while using different firefighting methods (nozzle, compressed air foam system, cutting extinguisher) and an extinguishing additive. New containers equipped with identical sets of combustible material were used for the five tests. The use of different firefighting methods and extinguishing additive induced variations in concentration and congener profiles of detected PBDD/Fs. The concentration range of Sigma PBDD/Fs in gas was 4020-18,700 pg/m(3), and in soot 76-4092 pg/m(2). PBDFs were the predominant congeners and 1,2,3,4,6,7,8-HpBDF was the most abundant congener. Chlorinated dibenzo-p-dioxins and furans (PCDD/Fs) were also monitored. The PBDD/Fs contributed with in average 97% to the total (PCDD/Fs plus PBDD/Fs) toxic equivalents, in soot and gas. During extinguishing, the shorter time the temperature was around 300 degrees C, the lower occurrence of PBDD/Fs. In the study the firefighting methods showed a difference in how effectively they induced a temperature decrease below 300 degrees C in the fire zone during quenching, where cutting extinguishing using additive and the compressed air foam system showed the fastest drop in temperature.

  • 238.
    Bjurlid, Filip
    et al.
    Örebro University, School of Science and Technology.
    Roos, Anna
    Department of Environmental Research and Monitoring, Swedish Museum of Natural History, Stockholm, Sweden.
    Ericson Jogsten, Ingrid
    Örebro University, School of Science and Technology.
    Hagberg, Jessika
    Örebro University, School of Science and Technology. Department of Occupational and Environmental Medicine, Faculty of Health and Medical Sciences, Örebro University, Örebro, Sweden.
    Temporal trends of PBDD/Fs, PCDD/Fs, PBDEs and PCBs in ringed seals from the Baltic Sea (Pusa hispida botnica) between 1974 and 20152018In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 616-617, p. 1374-1383Article in journal (Refereed)
    Abstract [en]

    Temporal trends in exposure to persistent organic pollutants (POPs) were assessed in 22 pooled samples gathered from 69 individuals of Baltic ringed seal (Pusa hispida botnica) from 1974 to 2015. Samples were analysed for polybrominated dibenzo-p-dioxins and furans (PBDD/Fs), polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs). No previous study has reported on the occurrence of PBDD/Fs in marine mammals in the Baltic Sea. Concentrations of pollutants in Baltic ringed seal, a marine mammal and top predator, can be used as an indicator of pollutants concentrations in the Baltic region.

    Visual inspection of data did not show any temporal trends for PBDD/Fs, while the PCDD/Fs and PCBs showed decreasing concentrations between 1974 and 2015. PBDEs increased until the end of the 1990s and then decreased until the end of the period. ∑ PBDD/Fs ranged from 0.5–52.3 pg/g lipid weight (l.w.) (0.08–4.8 pg TEQ/g l.w.), with 1,2,3,4,6,7,8-HpBDF contributing on average 61% to ∑ PBDD/Fs. ∑ PCDD/Fs ranged from 103 to 1480 pg/g l.w. (39–784 pg TEQ/g l.w.), with 1,2,3,6,7,8-HxCDD, 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDF showing the highest average concentrations. PBDD/F toxic equivalents (TEQ) contributed on average 1.1% to the total (PBDD/F + PCDD/F) TEQ. The ∑ PBDEs concentration range was 18.7–503 ng/g l.w., with BDE #47 the predominant congener. The concentration range for ∑ PCBs was 2.8–40.1 μg/g l.w., with #138 and #153 the most abundant congeners. Visual inspection of the data showed decreasing concentrations for all compound groups except PBDD/Fs. A slight increase in the PBDD/Fs concentrations was observed from 2004 onwards. This observation needs to be investigated further.

  • 239.
    Björk, Emelie
    Örebro University, School of Science and Technology.
    Isolation and Identification of Lactic Acid Bacteria in Certain Traditional Fermented Swedish Food2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 240.
    Björkbom, Carina
    et al.
    Laboratory of Aquatic Pathobiology, Environmental and Marine Biology, Department of Biosciences, Åbo Akademi University, Turku, Finland.
    Mustamäki, Noora
    Laboratory of Aquatic Pathobiology, Environmental and Marine Biology, Department of Biosciences, Åbo Akademi University, Turku, Finland.
    Olsson, Per-Erik
    Örebro University, School of Science and Technology.
    Katsiadaki, Ioanna
    Cefas Weymouth Laboratory, Weymouth, United Kingdom .
    Wiklund, Tom
    Laboratory of Aquatic Pathobiology, Environmental and Marine Biology, Department of Biosciences, Åbo Akademi University, Turku, Finland.
    Assessment of reproductive biomarkers in three-spined stickleback (Gasterosteus aculeatus) from sewage effluent recipients2013In: Environmental Toxicology, ISSN 1520-4081, E-ISSN 1522-7278, Vol. 28, no 4, p. 229-237Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to examine the occurrence of endocrine disruption close to sewage treatment plant effluent discharges along the Finnish Baltic Sea coast using a set of reproductive biomarkers present in adult three-spined stickleback (Gasterosteus aculeatus). Possible variation and sensitivity of the biomarkers during an entire reproductive period were also examined. The analysis of vitellogenin (VTG) for estrogenic activity and spiggin for androgenic activity, together with histopathological analysis indicated that sticklebacks were exposed to estrogenic loads sufficient to cause inappropriate production of VTG and to disrupt normal testicular structure in adult male sticklebacks. No androgenic disruption was observed. The results emphasize the need of a combination of several reproductive biomarkers in fish and repeated sampling for the detection of potential endocrine modulating substances under field condition

  • 241.
    Björkegren, Joakim
    et al.
    Örebro University, School of Science and Technology.
    Stenberg, Björn
    Örebro University, School of Science and Technology.
    Utveckling av drivmekanism för automatiserad paletthantering2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is a development project that deals with the transmission mechanism of pallets in robotic welding systems.

    Details to be welded are mounted on pallets. These are automatically transferred from a roller table to a workpiece positioner, holding the pallet in place during welding. The difficulty is due to the limited movements of the workpiece positioner. It is not always known what the customer wants to mount on the pallet. This limits the space available for the drive mechanism. The current system is built into the workpiece positioner. Increased competition has driven the need to reduce cost of the robotic welding systems. The drive mechanism for the pallets is an area where the company believes that costs can be cut.

    The report includes an idea generating process, development and simulation of a proposed solution to a design that replaces the current solution. The results section presents a solution proposal in the form of a conveyor which replaces both the current drive mechanism and one of the roller tables. Cost estimation is presented where the proposed solution is compared to today's solution.

  • 242.
    Björklund, Johanna
    Örebro University, School of Science and Technology.
    Framgångsrika recept för hållbara måltider i offentliga kök: Erfarenheter baserade på utvärderingen av projektet Hållbara måltider i Örebro län 2014-20162016Report (Other (popular science, discussion, etc.))
  • 243.
    Björklund, Johanna
    Örebro University, School of Science and Technology.
    Hållbara måltider i Örebro län 1.0: Ett bra exempel på lärande för hållbar utveckling2014Report (Other (popular science, discussion, etc.))
  • 244.
    Björklund, Johanna
    et al.
    Örebro University, School of Science and Technology.
    Araya, Hailu
    Institute for Sustainable Development, Addis Ababa, Ethiopia.
    Edwards, Sue
    Institute for Sustainable Development, Addis Ababa, Ethiopia.
    Goncalves, André
    Centro Ecológico, Instituto Federal Catarinense, Dom Pedro de Alcantara, Brazil.
    Höök, Karin
    Swedish Society for Nature Conservation, Stockholm, Sweden.
    Lundberg, Jakob
    Stockholm Resilience Centre Stockholm University, Stockholm, Sweden.
    Medina, Charito
    MASIPAG, Los Baños, Philippines.
    Ecosystem-based agriculture combining production and conservation: a viable way to feed the world in the long term?2012In: Journal of Sustainable Agriculture, ISSN 1044-0046, E-ISSN 1540-7578, Vol. 36, no 7, p. 824-855Article in journal (Refereed)
    Abstract [en]

    This study analyzed examples of sustainable ecosystem-based agriculture where management methods supported livelihoods of smallholders while at the same time local ecosystem services were enhanced in Ethiopia, Brazil, and the Philippines. Participation by farmers and collective actions were found to be a crucial driving force, as local specific knowledge and “learning by doing” were main components of the development. Social cohesion, particularly through associations and cooperatives, and improved marketing opportunities were also important drivers. Furthermore, recognition by authorities at all levels was perceived as crucial. Effects of climate change, insecure property rights, and political instability were potential threats. The possibilities of such systems to be scaled up beyond self-sufficiency raised further questions.

  • 245.
    Björklund, Johanna
    et al.
    Örebro University, School of Science and Technology.
    Eksvärd, Karin
    Inspire and action research ab.
    Schaffer, Christina
    Stockholms universitet, Stockholm, Sverige.
    Assessing ecosystem services in perennial intercropping systems: participatory action research in Swedish modern agrofores2014In: Farming systems facing global challenges: Capacities and strategies / [ed] Schobert, H., Riecher, M.-C., Fischer, H. Aenis, T. & Knierim, 2014, p. 112-113Conference paper (Other academic)
    Abstract [en]

    The focus of this paper is on how to assess ecosystem services in complex agroforestry systems using a case of edible forest gardens. Benefits of doing these assessments in a participatory learning and action research (PLAR) context are elaborated, as well as difficulties and questions that this has raised. The PLAR group comprised farmers on 13 smallholdings, researchers and a facilitator, which through collaboration and participatory methods have developed a general design of a forest garden, 60 m2 in size and established it on all 13 participating farms. Important values of the work are that ecosystem services are related to specific local contexts and that methodology for multi-criteria assessments of the generation of ecosystem services on a farm scale are being developed. Farmers engaged in formulating research questions, development of field trial designs, sampling and analysis of results improves the relevance and quality of the research as well as advance the adoption of new knowledge.

  • 246.
    Björklund, Johanna
    et al.
    Örebro University, School of Science and Technology.
    Eksvärd, Karin
    Inspire Action and Research AB, Knivsta, Sweden.
    Schaffer, Christina
    Department of Physical Geography, Stockholm University, Stockholm, Sweden.
    Exploring the potential of edible forest gardens: experiences from a participatory action research project in Sweden2018In: Agroforestry Systems, ISSN 0167-4366, E-ISSN 1572-9680Article in journal (Refereed)
    Abstract [en]

    To meet the environmental challenges that are presently confronting society, the narrow focus on agricultural production needs to be altered to one that places equal value on the generation of crucial ecosystem services. Current research shows that perennial intercropping systems such as agroforestry may be a feasible alternative. Based on studies during the establishment of edible forest gardens in 12 participating farms in Sweden, this paper explores the potential of utilizing multi-strata designs for food production in temperate, highincome countries. Design and species composition of such gardens, types of food they provide, and how they would best fit into the present landscape are discussed. Factors for success and major problems related to the establishment are shared. Potential benefits were found to be closely related to a thorough analysis of the social and ecological contexts before establishment. Characteristics of the site and goals of the garden need to guide species and design choices. If forest garden approaches to food production should contribute to more than local selfsufficiency, the gardens need to increase in scale. Marginal lands and transitions areas between different land uses may be appropriate. Large knowledge gaps concerning potential production, social and economic benefits, and agronomic issues were identified.

  • 247.
    Björklund, Johanna
    et al.
    Örebro University, School of Science and Technology.
    Johansson, Börje
    Hulta Norrgård, Linköping, Sweden.
    Assessing multifunctionality in relation to resource use: a holistic approach to measure efficiency, developed by participatory research2012In: Methods and procedures for building sustainable farming systems / [ed] Marta-Costa, A. A. & Soares da Silva, E. L. D. G, Dordrecht: Springer Netherlands, 2012, p. 161-173Chapter in book (Refereed)
    Abstract [en]

    Today’s intensive agriculture needs to be transformed into sustainable production of food, and this process requires good tools that can assess whether an action is leading towards this in the long term. A critical issue is what optimal yield comprises in terms of other functions of agriculture, as higher yields might lead to e.g. a reduction in biodiversity or soil carbon. In this study, emergy analysis and footprinting were combined to assess and illustrate the total resource use caused by a farming activity (milk production) and to identify the renewable fraction of this resource use. The total efficiency was defined as a function of the resource use and the multifunctionality of production. The classification of ecosystem services in the Millennium Ecosystem Assessment (MA) was used as the basis for ranking multifunctionality. The results were expressed in the form of ecosystem bundles for the four MA categories (provisioning, supporting, regulating and cultural functions). Three scenarios with different degrees of input intensity and milk production were constructed and compared with the current production mode. The ratio of local renewable resource use to total resource use differed greatly between the different production strategies, being 1:3 for a self-sufficient organic farm and 1:14 for a conventional farm with maximum milk yield. Milk production was five-fold higher on the conventional farm, while generation of ecosystem services increased with increasing self-sufficiency under the local conditions prevailing in the study. Ecosystem services in all categories except provisioning were ranked higher when self-sufficiency increased.

  • 248.
    Björklund, Johanna
    et al.
    Örebro University, School of Science and Technology.
    Morfeldt, Peter
    Att använda skolmåltiden som pedagogiskt redskap: Erfarenheter från en forskningscirkel med lärare i åk 5-­62015Report (Other (popular science, discussion, etc.))
  • 249.
    Björklund, Sofie
    Örebro University, School of Science and Technology.
    Validation of a Cleanup Method for Analysis of Novel Brominated Flame Retardants in Biota Matrices Sofie Björklund 2015-05-30 Supervisors Ingrid Ericson2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Brominated flame retardants is a group of compounds present in numerous types of materials in our surroundings. Although their purpose is to slow the progression of a fire, many has been shown to be toxic to the environment. Novel brominated flame retardants have been introduced to the market as old ones have been removed. Reliable methods are crucial to be able to monitor how the novel brominated flame retardant spread and accumulate in the environment. To achieve this, a method validation of a cleanup method using multilayer silica followed by analysis by atmospheric pressure gas chromatography coupled to tandem mass spectroscopy was performed. This method had been previously used for polybrominated diphenyl ethers and the aim was to see if it could be used for analysis of novel brominated flame retardants as well. Spiking experiments showed generally good results, with recoveries of the native compound ranging from 40% to 174%.

    To apply the method on real matrix samples, eight samples of osprey eggs and five samples of adipose tissue of ringed seal was analyzed. Several novel brominated flame retardants were found, most abundant being the methoxylated polybrominated diphenyl ethers. Dominant congener was 2'-Methoxy-2,3',4,5'-tetrabromodiphenyl ether (2PMBDE#68) followed by 6-Methoxy-2,2',4,4'-tetrabromodiphenyl ether (6PMBDE#47), 5-Methoxy-2,2',4,4'-tetrabromodiphenyl ether (5PMBDE#47) and 5-Methoxy-2,2',4,4',6-pentabromodiphenyl ether (5PMBDE#100) with concentrations ranging from <0,13-13 ng/g lipid weight in osprey eggs and <0,003-249 ng/g lipid weight in ringed seal blubber. Also 1,2-Bis(2,4,6-tribromophenoxy)ethane and pentabromobenzene were found in both osprey eggs and ringed seal blubber. Hexabromobenzene was found in ringed seal blubber and 2,3,5,6-tetrabromo-p-xylene was identified in osprey eggs.

  • 250.
    Björnsdotter, Maria
    Örebro University, School of Science and Technology.
    Leaching of Residual Monomers, Oligomers and Additives from Polyethylene, Polypropylene, Polyvinyl Chloride, High-density Polyethylene and Polystyrene Virgin Plastics2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Plastic debris are accumulating in our oceans and are degraded into smaller pieces which eventually becomes small enough to be available to lower thropic level organisms. Microplastics, commonly defined as plastic particles <5 mm, are globally distributed and found at remote locations far away from industrialized and populated areas. The effects of macro sized plastics is well understood whilst the effects of microplastics is hard to predict. It is known that microplastics act as transfer vectors for a wide range of toxic chemicals into organisms, and it is also known that the particle itself can cause toxic responses such as increased immune response and endocrine disruption. Researchers utilize virgin plastic pellets in order to determine the toxicological effect of the plastic particle itself, but resent research suggest that these virgin plastics may release chemicals that contribute to the toxic response and thus complicates the interpretation of the results. In present study, five different virgin plastics were allowed to leach in artificial seawater under conditions that mimic those used in particle toxicity studies. Plastics included were polyethylene, polypropylene, polyvinyl chloride, high-density polyethylene and polystyrene. Leachable monomers and oligomers were found in three of the five plastics tested: polyvinyl chloride, high-density polyethylene and polystyrene. Leached compounds from polyvinyl chloride were not identified due to time limitations. Aliphatic hydrocarbons in the size C14-C22 were leached out from high-density polyethylene in the concentration range 0.47 × 10-3 – 1.13 × 10-3 μg ml-1 within 24 hours. Polystyrene was found to leach styrene monomer which reached a concentration of 0.17 μg ml-1 within 24 hours.

2345678 201 - 250 of 1982
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