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  • 1.
    Adamovic, Tatjana
    et al.
    Dept Mol Med & Surg, Karolinska Inst, Stockholm, Sweden.
    McAllister, Donna
    Dept Surg, Med Coll Wisconsin, Milwaukee WI, USA.
    Wang, Tao
    Dept Biostat, Dept Populat Hlth, Med Coll Wisconsin, Milwaukee WI, USA.
    Adamovic, Dragan
    Örebro University, School of Science and Technology.
    Rowe, J. Jordi
    Dept Anat Pathol, Cleveland Clin, Cleveland OH, USA.
    Moreno, Carol
    Dept Physiol, Med Coll Wisconsin, Milwaukee WI, USA; Human & Mol Genet Ctr, Med Coll Wisconsin, Milwaukee WI, USA.
    Lazar, Josef
    Human & Mol Genet Ctr, Med Coll Wisconsin, Milwaukee WI, USA; Dept Dermatol, Med Coll Wisconsin, Milwaukee WI, USA.
    Jacob, Howard J.
    Dept Physiol, Med Coll Wisconsin, Milwaukee WI, USA; Med Coll Wisconsin, Human & Mol Genet Ctr, Milwaukee WI, USA; Dept Pediat, Med Coll Wisconsin, Milwaukee WI, USA.
    Sugg, Sonia L.
    Dept Surg, Univ Iowa, Iowa City IA, USA.
    Identification of novel carcinogen-mediated mammary tumor susceptibility loci in the rat using the chromosome substitution technique2010In: Genes, Chromosomes and Cancer, ISSN 1045-2257, E-ISSN 1098-2264, Vol. 49, no 11, p. 1035-1045Article in journal (Refereed)
    Abstract [en]

    We here report the genetic basis for susceptibility and resistance to carcinogen-mediated [7,12-dimethylbenz[a] anthracene (DMBA)] mammary tumorigenesis using the full panel of SS/BN consomic rat strains, in which substitutions of individual chromosomes from the resistant BN strain onto the genomic background of the susceptible SS strain were made. Analysis of 252 consomic females identified rat mammary Quantitative Trait Loci (QTLs) affecting tumor incidence on chromosomes 3 and 5, latency on chromosomes 3, 9, 14, and 19, and multiplicity on chromosomes 13, 16, and 19. In addition, we unexpectedly identified a novel QTL on chromosome 6 controlling a lethal toxic phenotype in response to DMBA. Upon further investigation with chromosomes 6 and 13 congenic lines, in which an additional 114 rats were investigated, we mapped (1) a novel mammary tumor QTL to a region of 27.1 Mbp in the distal part of RNO6, a region that is entirely separated from the toxicity phenotype, and (2) a novel and powerful mammary tumor susceptibility locus of 4.5 Mbp that mapped to the proximal q-arm of RNO13. Comparison of genetic strain differences using existing rat genome databases enabled us to further construct priority lists containing single breast cancer candidate genes within the defined QTLs, serving as potential functional variants for future testing.

  • 2.
    Ahlqvist, Max
    et al.
    Örebro University, School of Science and Technology.
    Hammarström, Niklas
    Örebro University, School of Science and Technology.
    UTVÄRDERING OCH UTVECKLING AV TRANSPORTFIXTURER FÖR BAKAXLAR:  2011Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been carried out in cooperation with Meritor HVS AB in Lindesberg that manufactures front and rear wheel axles for the bus and truck industry. The project focuses on fixtures used in the transportation of rear wheel axles. The goal of the project was to develop a new transport fixture that suits the majority of rear axle models and prevents damage during transport.

    The project is based on the systematic design methodology described by Johannesson, Persson and Pettersson (2004). Systematic design can be divided into five stages: product specification, concept generation, concept evaluation and selection, detailed design and final design.

    The main issue with Meritors fixtures is that they wear out easily and that the protective coating breaks. One fixture type needs to be able to handle the 30 rear axle models relevant to this project. Meritor currently uses a basic structure combined with miscellaneous temporary solutions to handle all models. The new conceptual fixture is limited by the current steel rack, it´s dimensions and fixture positions within the construction.

    Based on the concept designs put forward in the work, the two most suitable concepts were brought through to final design. The first concept, the T-fixture, was based on the fixture in use today and is thus an improvement. The improvement consists of an increased contact surface, better protective coating as well as weight and strength optimizations. Concept two, the Rod fixture, is also based on the same basic fixture but uses two loops that are available on every axle model. By placing the axle loops over the two rods in the fixture, a total immobilization of the axle is achieved.

  • 3.
    Ahmed, Muhammad Rehan
    Örebro University, School of Science and Technology.
    Compliance Control of Robot Manipulator for Safe Physical Human Robot Interaction2011Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Inspiration from biological systems suggests that robots should demonstrate same level of capabilities that are embedded in biological systems in performing safe and successful interaction with the humans. The major challenge in physical human robot interaction tasks in anthropic environment is the safe sharing of robot work space such that robot will not cause harm or injury to the human under any operating condition.

    Embedding human like adaptable compliance characteristics into robot manipulators can provide safe physical human robot interaction in constrained motion tasks. In robotics, this property can be achieved by using active, passive and semi active compliant actuation devices. Traditional methods of active and passive compliance lead to complex control systems and complex mechanical design.

    In this thesis we present compliant robot manipulator system with semi active compliant device having magneto rheological fluid based actuation mechanism. Human like adaptable compliance is achieved by controlling the properties of the magneto rheological fluid inside joint actuator. This method offers high operational accuracy, intrinsic safety and high absorption to impacts. Safety is assured by mechanism design rather than by conventional approach based on advance control. Control schemes for implementing adaptable compliance are implemented in parallel with the robot motion control that brings much simple interaction control strategy compared to other methods.

    Here we address two main issues: human robot collision safety and robot motion performance.We present existing human robot collision safety standards and evaluate the proposed actuation mechanism on the basis of static and dynamic collision tests. Static collision safety analysis is based on Yamada’s safety criterion and the adaptable compliance control scheme keeps the robot in the safe region of operation. For the dynamic collision safety analysis, Yamada’s impact force criterion and head injury criterion are employed. Experimental results validate the effectiveness of our solution. In addition, the results with head injury criterion showed the need to investigate human bio-mechanics in more details in order to acquire adequate knowledge for estimating the injury severity index for robots interacting with humans.

    We analyzed the robot motion performance in several physical human robot interaction tasks. Three interaction scenarios are studied to simulate human robot physical contact in direct and inadvertent contact situations. Respective control disciplines for the joint actuators are designed and implemented with much simplified adaptable compliance control scheme.

    The series of experimental tests in direct and inadvertent contact situations validate our solution of implementing human like adaptable compliance during robot motion and prove the safe interaction with humans in anthropic domains.

  • 4.
    Ahmed, Muhammad Rehan
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Semi-active compliant robot enabling collision safety for human robot interaction2010In: 2010 International Conference on Mechatronics and Automation (ICMA), IEEE, 2010, p. 1932-1937Conference paper (Refereed)
    Abstract [en]

    Human robot interaction (HRI) tasks requires robots to have safe sharing of work space and to demonstrate adaptable compliant behavior enabling eminent collision safety as well as maintaining high position accuracy. Robot compliance control normally can be achieved by using active compliance control of actuators based on various sensor data. Alternatively, passive devices allow controllable compliance motion but usually are mechanically complex. We proposed a unique method using semi-active compliant actuation mechanism having magneto-rheological (MR) fluid based actuator that introduces reconfigurable compliance characteristics into the robot joints. This enables high intrinsic safety coming from fluid mechanics as well as, it offers simpler interaction control strategy compared to other concurrent approaches. In this studies, we have described three essential modes of motions required for physical human system interaction. Furthermore, we have demonstrated robot collision safety in terms of static collision and experimentally validates the performance of robot manipulator enabling safe human robot interaction.

  • 5.
    Ahmed, Muhammad Rehan
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Static and dynamic collisionsafety for human robot interaction using magneto-rheological fluid based compliant robot manipulator2010In: IEEE international conference on robotics and biomimetics (ROBIO), 2010, IEEE conference proceedings, 2010, p. 370-375Conference paper (Refereed)
    Abstract [en]

    The success of human robot interaction (HRI) tasks is characterized by evaluating robot performance in terms of collision safety and position accuracy. Hence, both position accuracy and collision safety are equally indispensable. HRI refers to cognitive as well as physical interaction. Cognitive human robot interaction based on perception and awareness where as physical human robot interaction demands direct contact with the humans exhibiting adaptable compliant behavior. Therefore, development of ideal safe robot manipulator having adaptable compliant actuation is inevitable. Adaptable compliance can be achieved by using active compliant actuation requiring various sensor data or by using passive compliant devices with high mechanical complexity. We present magneto rheological fluid based compliant actuation mechanism introducing adaptable compliance directly into robotic joint with much simpler interaction control and higher intrinsic safety originating from fluid mechanics. In this study, we have discussed adaptable compliance in terms of essential modes of motion for safe physical HRI and evaluated the safety performance of our robot for static collision testing and dynamic collision testing based on impact force and head injury criterion. Finally, the experimental results validate the significance of our proposed method for both human robot collision safety and high position accuracy.

  • 6.
    Ahmed, Muhammad Rehan
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Static collision analysis of semi active compliant robot for safe human robot interaction2010In: Proceedings of the 12th Mechatronics Forum Biennial International Conference, IWF Institute of Machine tools and manufacturing , 2010, p. 220-227Conference paper (Refereed)
  • 7.
    Ahmed, Muhammad Rehan
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Two link compliant robot manipulator for physical human robot collision safety2012In: Biomedical Engineering Systems and Technologies / [ed] Ana Fred, Joaquim Filipe, Hugo Gamboa, Springer, 2012Conference paper (Refereed)
  • 8.
    Ahmed, Rehan M.
    et al.
    Örebro University, School of Science and Technology.
    Ananiev, Anani V.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Compliant motion control for safe human robot interaction2009In: Robot motion and control 2009 / [ed] Krzysztof R. Kozłowski, Berlin: Springer , 2009, p. 265-274Conference paper (Refereed)
    Abstract [en]

    Robots have recently been foreseen to work side by side and share workspace with humans in assisting them in tasks that include physical human-robot (HR) interaction. The physical contact with human tasks under uncertainty has to be performed in a stable and safe manner [6]. However, current industrial robot manipulators are still very far from HR coexisting environments, because of their unreliable safety, rigidity and heavy structure. Besides this, the industrial norms separate the two spaces occupied by a human and a robot by means of physical fence or wall [9]. Therefore, the success of such physical HR interaction is possible if the robot is enabled to handle this interaction in a smart way to prevent injuries and damages.

  • 9.
    Ahmed, Rehan M.
    et al.
    Örebro University, School of Science and Technology.
    Ananiev, Anani V.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan G.
    Örebro University, School of Science and Technology.
    Safe robot with reconfigurable compliance/stiffness actuation2009In: Proceedings of ASME/IFToMM International Conference on Reconfigurable Mechanisms and Robots. ReMAR'2009 / [ed] J. S. Dai, M. Zoppi, X. W. Kong, IEEE, 2009, p. 633-638Conference paper (Refereed)
    Abstract [en]

    Human robot interaction (HRI) in constrained motion tasks requires robots to have safe sharing of work space and to demonstrate adaptable compliant behavior Compliance control of industrial robots, normally can be achieved by using active compliance control of actuators based on various sensor data. Alternatively, passive devices allow controllable compliance motion but usually are mechanically complex. We present a unique method using a novel actuation mechanism based on magneto-rheological fluid (MRF) that incorporates reconfigurable compliance directly into the robot joints. This brings much simple interaction control strategy compared to other antagonistic methods. In this studies, we have described three essential modes of motions required for physical human system interaction. Then we have discussed their respective control disciplines. Finally, we have presented functional performance of reconfigurable MRF actuation mechanism in constrained motion tasks by simulating various HRI scenarios.

  • 10.
    Ahmed, Rehan M.
    et al.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Ananiev, Anani
    Örebro University, School of Science and Technology.
    Modeling of magneto rheological fluid actuator enabling safe human-robot interaction2008In: IEEE International Conference on Emerging Technologies and Factory Automation, 2008. ETFA 2008, 2008, p. 974-979Conference paper (Refereed)
    Abstract [en]

    Impedance control and compliant behavior for safe human-robot physical interaction of industrial robots normally can be achieved by using active compliance control of actuators based on various sensor data. Alternatively, passive devices allow controllable compliance motion but usually are mechanically complex. We present another approach using a novel actuation mechanism based on magneto-rheological fluid (MRF) that incorporates variable stiffness directly into the joints. In this paper, we have investigated and analyzed principle characteristics of MRF actuation mechanism and presented the analytical-model. Then we have developed the static and dynamic model based on experimental test results and have discussed three essential modes of motion needed for human-robot manipulation interactive tasks.

  • 11. Alegret, Joan
    et al.
    Johansson, Peter
    Örebro University, School of Science and Technology.
    Käll, Mikael
    Green’s tensor calculations of plasmon resonances of single holes and hole pairs in thin gold films2008In: New Journal of Physics, ISSN 1367-2630, E-ISSN 1367-2630, Vol. 10, no 105004Article in journal (Refereed)
    Abstract [en]

    We present numerical calculations of the plasmon properties of single-hole and hole-pair structures in optically thin gold films obtained with the Green’s tensor formalism for stratified media. The method can be used to obtain the optical properties of a given hole system, without problems associated with the truncation of the infinite metal film. The calculations are compared with previously published experimental data and an excellent agreement is found. In particular, the calculations are shown to reproduce the evolution of the hole plasmon resonance spectrum as a function of hole diameter, film thickness and hole separation.

  • 12.
    Alklind Taylor, Anna-Sofia
    Örebro University, School of Science and Technology.
    Coaching by gaming: an instructor perspective of game-based vocational training2011Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Military organisations have a long history of using games for training. Over the years, they have developed training practices involving role-play, simulations, puckstering and gaming. Most researchers in serious games, i.e. games used for non-entertainment purposes, focus their studies on the learners. This licentiate thesis, instead, takes a closer look on the roles of instructors in game-based training situations, specifically at the Swedish Land Warfare Centre. Through a mix of theoretical and empirical studies, training practices were scrutinised, resulting in a framework for gamebased vocational training. A key element of this framework is the coaching by gaming perspective in which instructors give un-intrusive, formative feedback through role-play and gameplay. Another important aspect of the framework involves dynamic debriefing. These insights points to specific needs for system support for instructors involved in game-based training. They also emphasise the fact that serious gaming is a highly contextualised activity made up of more than the game and the players

    List of papers
    1. Letting the students create and the teacher play: expanding the roles in serious gaming
    Open this publication in new window or tab >>Letting the students create and the teacher play: expanding the roles in serious gaming
    2011 (English)In: MindTrek'11: Proceedings of the 15th International Academic MindTrek Conference: Envisioning Future Media Environments, New York: ACM Special Interest Group on Computer Science Education, 2011, p. 63-70Conference paper, Published paper (Other academic)
    Abstract [en]

    Military organisations have a long history of using games for training. Over the years, they have developed training practices involving role-play, simulations, puckstering and gaming. Most researchers in serious games, i.e. games used for non-entertainment purposes, focus their studies on the learners. This licentiate thesis, instead, takes a closer look on the roles of instructors in game-based training situations, specifically at the Swedish Land Warfare Centre. Through a mix of theoretical and empirical studies, training practices were scrutinised, resulting in a framework for gamebased vocational training. A key element of this framework is the coaching by gaming perspective in which instructors give un-intrusive, formative feedback through role-play and gameplay. Another important aspect of the framework involves dynamic debriefing. These insights points to specific needs for system support for instructors involved in game-based training. They also emphasise the fact that serious gaming is a highly contextualised activity made up of more than the game and the players.

    Place, publisher, year, edition, pages
    New York: ACM Special Interest Group on Computer Science Education, 2011
    Keywords
    Coaching cycle, debriefing, game-based training, instructor roles, player roles, puckstering, serious games, serious gaming, system support
    National Category
    Computer and Information Sciences
    Research subject
    Informatics
    Identifiers
    urn:nbn:se:oru:diva-20749 (URN)10.1145/2181037.2181049 (DOI)978-1-4503-0816-8 (ISBN)
    Conference
    MindTrek 2011, Tampere, Finland, September 28-30, 2011
    Available from: 2012-01-09 Created: 2012-01-09 Last updated: 2018-05-03Bibliographically approved
    2. Introducing the coaching cycle: a coaching by gaming perspective of serious gaming
    Open this publication in new window or tab >>Introducing the coaching cycle: a coaching by gaming perspective of serious gaming
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Military organizations have a long history of using simulations, role-play and games for training. This also encompasses good practices concerning how instructors utilize games and gaming behavior. Unfortunately, the work of instructors is rarely described explicitly in research relating to serious gaming. Decision makers also tend to have overconfidence in the pedagogical power in games and simulations, where the instructor is taken out of the gaming loop. We propose a framework, the coaching cycle, that focuses on the roles of instructors. The roles include instructors acting as game players. The fact that the instructors take a more active part in all training activities will further improve learning. The coaching cycle integrates theories of experiential learning (where action precedes theory) and deliberate practice (where the trainee’s skill is constantly challenged by a coach). Incorporating a coaching by gaming perspective complicates, but also strengthens, the player-centered design approach to game development in that you need to take into account two different types of players: trainees and instructor. Furthermore, we argue that the coaching cycle allows for a shift of focus to more thorough debriefing, since it implies that learning of theoretical material before simulation/game playing is kept to a minimum. This shift will increase the transfer of knowledge.

    National Category
    Computer and Information Sciences
    Research subject
    Computer and Systems Science
    Identifiers
    urn:nbn:se:oru:diva-20754 (URN)
    Available from: 2012-01-09 Created: 2012-01-09 Last updated: 2018-01-12Bibliographically approved
  • 13.
    Alklind Taylor, Anna-Sofia
    Örebro University, School of Science and Technology.
    Introducing the coaching cycle: a coaching by gaming perspective of serious gamingManuscript (preprint) (Other academic)
    Abstract [en]

    Military organizations have a long history of using simulations, role-play and games for training. This also encompasses good practices concerning how instructors utilize games and gaming behavior. Unfortunately, the work of instructors is rarely described explicitly in research relating to serious gaming. Decision makers also tend to have overconfidence in the pedagogical power in games and simulations, where the instructor is taken out of the gaming loop. We propose a framework, the coaching cycle, that focuses on the roles of instructors. The roles include instructors acting as game players. The fact that the instructors take a more active part in all training activities will further improve learning. The coaching cycle integrates theories of experiential learning (where action precedes theory) and deliberate practice (where the trainee’s skill is constantly challenged by a coach). Incorporating a coaching by gaming perspective complicates, but also strengthens, the player-centered design approach to game development in that you need to take into account two different types of players: trainees and instructor. Furthermore, we argue that the coaching cycle allows for a shift of focus to more thorough debriefing, since it implies that learning of theoretical material before simulation/game playing is kept to a minimum. This shift will increase the transfer of knowledge.

  • 14.
    Alklind Taylor, Anna-Sofia
    et al.
    Örebro University, School of Science and Technology.
    Backlund, Per
    University of Skövde, Skövde, Sweden.
    Letting the students create and the teacher play: expanding the roles in serious gaming2011In: MindTrek'11: Proceedings of the 15th International Academic MindTrek Conference: Envisioning Future Media Environments, New York: ACM Special Interest Group on Computer Science Education, 2011, p. 63-70Conference paper (Other academic)
    Abstract [en]

    Military organisations have a long history of using games for training. Over the years, they have developed training practices involving role-play, simulations, puckstering and gaming. Most researchers in serious games, i.e. games used for non-entertainment purposes, focus their studies on the learners. This licentiate thesis, instead, takes a closer look on the roles of instructors in game-based training situations, specifically at the Swedish Land Warfare Centre. Through a mix of theoretical and empirical studies, training practices were scrutinised, resulting in a framework for gamebased vocational training. A key element of this framework is the coaching by gaming perspective in which instructors give un-intrusive, formative feedback through role-play and gameplay. Another important aspect of the framework involves dynamic debriefing. These insights points to specific needs for system support for instructors involved in game-based training. They also emphasise the fact that serious gaming is a highly contextualised activity made up of more than the game and the players.

  • 15.
    Allard, Bert
    Örebro University, School of Science and Technology.
    Uranbrytning i Sverige: ett miljöproblem?2009Conference paper (Refereed)
  • 16.
    Allard, Bert
    et al.
    Örebro University, School of Science and Technology.
    Bäckström, Mattias
    Örebro University, School of Science and Technology.
    Häller, Sara
    Örebro University, School of Science and Technology.
    Panova, Elena
    St Petersburgs universitet, St Petersburg, Ryssland.
    Grawunder, Anja
    Friedrich Sciller Univ., Jena, Germany.
    Karlsson, Stefan
    Örebro University, School of Science and Technology.
    Water chemistry and trace metal concentrations in an acidic alum shale pit lake: effects of liming2011In: Mine water: managing the challenges: proceedings of the International Mine Water Association Congress 2011 / [ed] Trude R.Rüde, Antje Freund, Christian Wolkersdorfer, Aachen: RWTH , 2011, p. 503-508Conference paper (Refereed)
  • 17.
    Allard, Bert
    et al.
    Örebro University, School of Science and Technology.
    Sartz, Lotta
    Örebro University, School of Science and Technology.
    Karlsson, Stefan
    Örebro University, School of Science and Technology.
    Bäckström, Mattias
    Örebro University, School of Science and Technology.
    Metal releases from historic sulphidic mine site (Ljusnarsberg, Sweden): mobilization and attenuation processes2008Conference paper (Refereed)
  • 18.
    Almestrand, Lovisa
    Örebro University, School of Science and Technology.
    Passivhus i Örebro län: Undersökning av marknaden för fastighetsägare2009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project aims to study the knowledge that property owners have of passive houses and if there is a market for this concept in Örebro County.

    Environmental and climate problems in the world are growing and a result of this is the constant circulating debate of passive houses. Low-energy houses are a necessary solution to reducing energy consumption, then the housing sector accounts for about 40 % of Sweden´s total energy use. Passive houses are a development of the low-energy house built without conventional heating systems and have a low energy use. Asplunds Bygg in Örebro is now building the very first passive houses in Örebro this spring 2009.

    The project began with contacting property owners to book interviews. The interviews were carried out over a four week period at the respective property owner's office. An independent in-depth were made parallel to the interviews by studying passivhus in literature, articles and on the Internet. The results of the interviews were compiled, compared and analyzed based on the purpose of the work.

    Property owners are receptive to the concept and believe that the energy issue is important, but that knowledge into passive houses of some is poor.  Finally found that from the results of the interviews it seems that there is a future market for passive houses in Örebro County. 

    Keywords: passive houses, low-energy houses, energy use, ventilation system, heat recovery, thick insulation.  

  • 19.
    Andersson, Emelie
    Örebro University, School of Science and Technology.
    Jämförande studie avseende svenska byggregler och den europeiska standarden eurokoder: Inriktning husbyggnad och betongkonstruktion2009Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den Europeiska standarden är indelad i flertalet Eurokoder och dessa är de kommande beräkningsreglerna som år 2011 blir obligatoriska för alla bärande konstruktioner inom den Europeiska unionen. De kommer att ersätta tidigare nationella regler och det är framförallt Boverkets konstruktionsregler (BKR) med tillhörande handböcker som berörs av Eurokoderna.

    Flertalet faktorer påverkar när en övergång från svenska byggregler till Eurokoderna skall bli möjlig men det viktigaste har med dess tillgänglighet att göra. Det är inte längre en fråga om Eurokoderna skall börja tillämpas, utan istället när.

    Syftet med detta examensarbete är att det skall ge en allmän och överskådlig bild av hur de svenska byggreglerna skiljer sig från sin europiska motsvarighet, varvid likheter och olikheter skall lyftas fram.

    Jämförelsen har baserats på ett antal beräkningar som har utförts på ett framtaget referensobjekt, där endast de delar som berör beräkningar kring referensobjektet kommer att granskas och jämföras. För att få underlag till dessa beräkningar har litteraturstudium av respektive regler tillämpats. Detta material har allt eftersom sammanställts i denna rapport.

    Med utgångspunkt från det framtagna referensobjektet kan man till stor del fastlägga att skillnaden mellan svenska byggregler och europeisk standard inte är av större karaktär. En av de mest framgående skillnaderna är dock att den europeiska standarden är betydligt mer beskrivande om hur och vad som skall beräknas, vägen till resultatet, medan de svenska byggreglerna endast beskriver det slutgiltiga resultatet. Detta leder till att den europeiska standarden är betydligt lättare att följa och därav även lättare att tillämpa.

  • 20.
    Andersson, Erika
    et al.
    Örebro University, School of Science and Technology.
    Rotander, Anna
    Örebro University, School of Science and Technology.
    von Kronhelm, Thomas
    SAKAB.
    Berggren, Anna
    Analycen AB.
    Ivarsson, Per
    Analycen AB.
    Hollert, Henner
    RWTH Aachen university.
    Engwall, Magnus
    Örebro University, School of Science and Technology.
    AhR agonist and genotoxicant bioavailability in a PAH-contaminated soil undergoing biological treatment2009In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 16, no 5, p. 521-530Article in journal (Refereed)
    Abstract [en]

    Degradation of the 16 US EPA priority PAHs in soil subjected to bioremediation is often achieved. However, the PAH loss is not always followed by a reduction in soil toxicity. For instance, bioanalytical testing of such soil using the chemical-activated luciferase gene expression (CALUX) assay, measuring the combined effect of all Ah receptor (AhR) activating compounds, occasionally indicates that the loss of PAHs does not correlate with the loss of Ah receptor-active compounds in the soil. In addition, standard PAH analysis does not address the issue of total toxicant bioavailability in bioremediated soil.

    To address these questions, we have used the CALUX AhR agonist bioassay and the Comet genotoxicity bioassay with RTL-W1 cells to evaluate the toxic potential of different extracts from a PAH-contaminated soil undergoing large-scale bioremediation. The extracts were also chemically analyzed for PAH16 and PCDD/PCDF. Soil sampled on five occasions between day 0 and day 274 of biological treatment was shaken with n-butanol with vortex mixing at room temperature to determine the bioavailable fraction of contaminants. To establish total concentrations, parts of the same samples were extracted using an accelerated solvent extractor (ASE) with toluene at 100A degrees C. The extracts were tested as inducers of AhR-dependent luciferase activity in the CALUX assay and for DNA breakage potential in the Comet bioassay.

    The chemical analysis of the toluene extracts indicated slow degradation rates and the CALUX assay indicated high levels of AhR agonists in the same extracts. Compared to day 0, the bioavailable fractions showed no decrease in AhR agonist activity during the treatment but rather an up-going trend, which was supported by increasing levels of PAHs and an increased effect in the Comet bioassay after 274 days. The bio-TEQs calculated using the CALUX assay were higher than the TEQs calculated from chemical analysis in both extracts, indicating that there are additional toxic PAHs in both extracts that are not included in the chemically derived TEQ.

    The response in the CALUX and the Comet bioassays as well as the chemical analysis indicate that the soil might be more toxic to organisms living in soil after 274 days of treatment than in the untreated soil, due to the release of previously sorbed PAHs and possibly also metabolic formation of novel toxicants.

    Our results put focus on the issue of slow degradation rates and bioavailability of PAHs during large-scale bioremediation treatments. The release of sorbed PAHs at the investigated PAH-contaminated site seemed to be faster than the degradation rate, which demonstrates the importance of considering the bioavailable fraction of contaminants during a bioremediation process.

    It has to be ensured that soft remediation methods like biodegradation or the natural remediation approach do not result in the mobilization of toxic compounds including more mobile degradation products. For PAH-contaminated sites this cannot be assured merely by monitoring the 16 target PAHs. The combined use of a battery of biotests for different types of PAH effects such as the CALUX and the Comet assay together with bioavailability extraction methods may be a useful screening tool of bioremediation processes of PAH-contaminated soil and contribute to a more accurate risk assessment. If the bioremediation causes a release of bound PAHs that are left undegraded in an easily extracted fraction, the soil may be more toxic to organisms living in the soil as a result of the treatment. A prolonged treatment time may be one way to reduce the risk of remaining mobile PAHs. In critical cases, the remediation concept might have to be changed to ex situ remediation methods.

  • 21.
    Andersson, Lena
    Örebro University, School of Science and Technology.
    Quartz in Swedish iron foundries: exposure and cancer risk2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The aims of the studies underlying this thesis were to assess the exposure to quartz in Swedish iron foundries and to determine the cancer morbidity for Swedish foundry workers. A cohort of 3,045 foundry workers and a final measurement database of 2,333 number of samples was established.

    The exposure measurements showed high levels of respirable quartz, in particular for fettlers and furnace and ladle repair workers with individual 8 hr TWA (GM=0.041 and 0.052 mg/m3; range 0.004-2.1 and 0.0098-0.83 mg/m3). In our database, the quartz concentrations as 8hr TWAs of current and historical data varied between 0.0018 and 4.9 mg/m3, averaging 0.083 mg/m3, with the highest exposures for fettlers (0.087 mg/m3) and furnace and ladle repair workers (0.42 mg/m3). The exposure for workers using respirators assuming full effect when used were assessed quantitatively, revealing workers with actual exposure exceeding the occupational exposure limits.

    Overall cancer morbidity was not increased, but the incidence of lung cancer was significantly elevated (SIR 1.61; 95 % CI 1.20-2.12). In the cohort study, significant associations between lung cancer and cumulative quartz exposure were detected for quartz doses of 1-2 mg/m3 * year (SIR 2.88; 95 % CI 1.44-5.16) and >2 mg/m3 * year (SIR 1.68; 95 % CI 1.07- 2.52). These findings were not confirmed in the case-control analysis.

    The agreement between the estimated exposure in our early historical model and the development model showed a regression coefficient of 2.42, implying an underestimation of the historical exposure when using the development model data. The corresponding comparison between the development and the validation model based on our survey data showed a B of 0.31, implying an overestimation of present exposures when using data from the validation model.

    The main conclusions of the thesis are that certain foundry workers are still exposed to high levels of quartz, and the overall excess lung cancer could not be confirmed in the exposure-response analysis.

    List of papers
    1. Quartz and dust exposure in Swedish iron foundries
    Open this publication in new window or tab >>Quartz and dust exposure in Swedish iron foundries
    Show others...
    2009 (English)In: Journal of Occupational and Environmental Hygiene, ISSN 1545-9624, E-ISSN 1545-9632, Vol. 6, no 1, p. 9-18Article in journal (Refereed) Published
    Abstract [en]

    Exposure to respirable quartz continues to be a major concern in the Swedish iron foundry industry. Recommendations for reducing the European occupational exposure limit (EU-OEL) to 0.05 mg/m3 and the corresponding ACGIH® threshold limit value (ACGIH-TLV) to 0.025 mg/m3 prompted this exposure survey. Occupational exposure to respirable dust and respirable quartz were determined in 11 Swedish iron foundries, representing different sizes of industrial operation and different manufacturing techniques. In total, 436 respirable dust and 435 respirable quartz exposure measurements associated with all job titles were carried out and are presented as time-weighted averages. Our sampling strategy enabled us to evaluate the use of respirators in certain jobs, thus determining actual exposure. In addition, measurements using real-time dust monitors were made for high exposure jobs. For respirable quartz, 23% of all the measurements exceeded the EU-OEL, and 56% exceeded the ACGIH-TLV. The overall geometric mean (GM) for the quartz levels was 0.028 mg/m3, ranging from 0.003 to 2.1 mg/m3. Fettler and furnace and ladle repair operatives were exposed to the highest levels of both respirable dust (GM = 0.69 and 1.2 mg/m3; range 0.076-31 and 0.25-9.3 mg/m3 and respirable quartz (GM = 0.041 and 0.052 mg/m3; range 0.004-2.1 and 0.0098-0.83 mg/m3. Fettlers often used respirators and their actual quartz exposure was lower (range 0.003-0.21 mg/m3, but in some cases it still exceeded the Swedish OEL (0.1 mg/m3. For furnace and ladle repair operatives, the actual quartz exposure did not exceed the OEL (range 0.003-0.08 mg/m3, but most respirators provided insufficient protection, i.e., factors less than 200. In summary, measurements in Swedish iron foundries revealed high exposures to respirable quartz, in particular for fettlers and furnace and ladle repair workers. The suggested EU-OEL and the ACGIH-TLV were exceeded in, respectively, 23% and 56% of all measurements regardless of the type of foundry. Further work on elimination techniques to reduce quartz concentrations, along with control of personal protection equipment, is essential.

    Place, publisher, year, edition, pages
    Philadelphia, PA: Taylor & Francis, 2009
    Keywords
    exposure, iron foundry, quartz; respirators
    National Category
    Medical and Health Sciences Occupational Health and Environmental Health
    Research subject
    Occupational and Environmental Medicine
    Identifiers
    urn:nbn:se:oru:diva-3404 (URN)10.1080/15459620802523943 (DOI)000261508800002 ()18982534 (PubMedID)
    Available from: 2008-12-04 Created: 2008-12-04 Last updated: 2018-01-13Bibliographically approved
    2. Cancer morbidity and quartz exposure in Swedish iron foundries
    Open this publication in new window or tab >>Cancer morbidity and quartz exposure in Swedish iron foundries
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    (English)Manuscript (preprint) (Other academic)
    Keywords
    Cohort study, lung cancer, occupational exposure, respirable silica, smoking habits
    National Category
    Medical and Health Sciences Occupational Health and Environmental Health
    Research subject
    Occupational and Environmental Medicine
    Identifiers
    urn:nbn:se:oru:diva-21292 (URN)
    Available from: 2012-01-24 Created: 2012-01-24 Last updated: 2018-01-12Bibliographically approved
    3. Exposure assessment and modeling of quartz in Swedish iron foundries for a nested case-control study on lung cancer
    Open this publication in new window or tab >>Exposure assessment and modeling of quartz in Swedish iron foundries for a nested case-control study on lung cancer
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    2012 (English)In: Journal of Occupational and Environmental Hygiene, ISSN 1545-9624, E-ISSN 1545-9632, Vol. 9, no 2, p. 110-119Article in journal (Refereed) Published
    Abstract [en]

    Exposure assessment of quartz in Swedish iron foundries was performed based on historical and present measurement data. To evaluate the exposure response relationship between quartz exposure and lung cancer, we modeled quartz exposure from our database of measurements using determinants job title, time period and company. Based on these modeled exposure data, we conducted a nested case– control evaluation.

    In our database, the overall individual daily time-weighted average (TWA) quartz concentrations of current and historical data varied between 0.0018 and 4.9 mg/m3, averaging 0.083 mg/m3. The job titles with mean TWAs for the whole study period exceeding the European Union recommended occupational exposure limit of 0.05 mg/m3 were fettlers (0.087 mg/m3), furnace and ladle repair (0.42 mg/m3) and maintenance (0.054 mg/m3) workers.

    The mixed model analysis demonstrated significant determinants on the job level for furnace and ladle repair (β=4.06; 95% CI 2.78-5.93). For all jobs significantly higher exposure levels occurred only during the first time period, 1968-1979 (β=2.08; 95% CI 1.75-2.47), and a decreasing but not significant trend was noted for the three following 10 year time periods up to 2006 (β=1.0, 0.96 and 1, respectively). Two iron foundries had significantly higher quartz concentration levels than the others (β=1.31; 95% CI 1.00-1.71 and β=1.63; 95% CI 1.00-2.65, respectively). The individual cumulative quartz exposure measures were categorized in low, medium and high exposure (0.5-<1, 1-1.9 and ≥2 mg/m3 *years, respectively).

    In the nested case-control analysis, we found the highest odds ratios of lung cancer (OR 1.17; 95% CI 0.53-2.55) for the medium exposure group. No dose– response trend or significantly increased risk was determined for our high exposed group (≥2 mg/m3), representing 40 years of exposure at >0.05 mg/m3 of quartz. To conclude, certain foundry workers are still exposed to high levels of quartz, but an increased risk of lung cancer caused by quartz exposure in these Swedish iron foundries could not be confirmed at our exposure levels.

    Place, publisher, year, edition, pages
    Philadelphia: Taylor & Francis, 2012
    Keywords
    Exposure modeling, iron foundry, lung cancer, quartz
    National Category
    Medical and Health Sciences Occupational Health and Environmental Health
    Research subject
    Occupational and Environmental Medicine
    Identifiers
    urn:nbn:se:oru:diva-21293 (URN)10.1080/15459624.2011.645397 (DOI)000300962700009 ()22239127 (PubMedID)2-s2.0-84860878860 (Scopus ID)
    Funder
    AFA Insurance
    Note

    Funding Abency:

    AFA, Stockholm 

    Available from: 2012-01-24 Created: 2012-01-24 Last updated: 2018-05-08Bibliographically approved
    4. Estimating trends in quartz exposure in Swedish iron foundries: predicting past and present exposures
    Open this publication in new window or tab >>Estimating trends in quartz exposure in Swedish iron foundries: predicting past and present exposures
    2012 (English)In: Annals of Occupational Hygiene, ISSN 0003-4878, E-ISSN 1475-3162, Vol. 56, no 3, p. 362-372Article in journal (Refereed) Published
    Abstract [en]

    Background: Swedish foundries have a long tradition of legally required surveys in the work place that, from the late 1960s onwards, included measurements of quartz. The availability of exposure data spanning almost 40 years presents a unique opportunity to study trends over that time and to evaluate the validity of exposure models based on data from shorter time spans. The aims of this study were (i) to investigate long term trends in quartz exposure over time, (ii) using routinely collected quartz exposure measurements to develop a mathematical model that could predict both historical and current exposure patterns, and (iii) to validate this exposure model with up-to-date measurements from a targeted survey of the industry.

    Methods: Eleven foundries, representative of the Swedish iron foundry industry, were divided into three groups based on the size of the companies, i.e. the number of employees. A database containing 2333 quartz exposure measurements for 11 different job descriptionswas used to create three models that covered time periods which reflected different work conditions and production processes: a historical model (1968– 1989), a development model (1990–2004), and a validation model (2005–2006). A linear mixed model for repeated measurements was used to investigate trends over time. In all mixed models, time period, company size, and job title were included as fixed (categorical) determinants of exposure. The within- and between-worker variances were considered to be random effects. A linear regression analysis was erformed to investigate agreement between the models. The average exposure was estimated for each combination of job title and company size.

    Results: A large reduction in exposure (51%) was seen between 1968 and 1974 and between 1975 and 1979 (28%). In later periods, quartz exposure was reduced by 8% per 5 years at best. In the first period, employees at smaller companies experienced ~50%higher exposure levels than those at large companies, but these differences became much smaller in later years. The furnace and ladle repair job were associated with the highest exposure, with 3.9–8.0 times the average exposure compared to the lowest exposed group. Without adjusting for this autonomous trend over time, predicting early historical exposures using our development model resulted in a statistically significant regression coefficient of 2.42 (R2 5 0.81), indicating an underestimation of historical exposure levels. Similar patterns were seen for other historical time periods. Comparing our development model with our validation model resulted in a statistically significant regression coefficient of 0.31, indicating an overestimation of current exposure levels.

    Conclusion: To investigate long-term trends in quartz exposure over time, overall linear trends can be determined by using mixed model analysis. To create individual exposure measures to predict historical exposures, it is necessary to consider factors such as the time period, type of job, type of company, and company size. The mixed model analysis showed systematic changes in concentration levels, implying that extrapolation of exposure estimates outside the range of years covered by measurements may result in underestimation or overestimation of exposure.

    Place, publisher, year, edition, pages
    Oxford, United Kingdom: Oxford University Press, 2012
    Keywords
    Iron foundry, predicting exposures, quartz, time trends
    National Category
    Medical and Health Sciences Occupational Health and Environmental Health
    Research subject
    Occupational and Environmental Medicine
    Identifiers
    urn:nbn:se:oru:diva-21296 (URN)10.1093/annhyg/mer106 (DOI)000302015600011 ()22104319 (PubMedID)2-s2.0-84858671192 (Scopus ID)
    Available from: 2012-01-24 Created: 2012-01-24 Last updated: 2018-05-08Bibliographically approved
  • 22.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Camera based navigation by mobile robots: local visual feature based localisation and mapping2009Book (Other academic)
    Abstract [en]

    The most important property of a mobile robot is the fact that it is mobile. How to give a robot the skills required to navigate around its environment is therefore an important topic in mobile robotics. Navigation, both for robots and humans, typically involves a map. The map can be used, for example, to estimate a pose based on observations (localisation) or determine a suitable path between to locations. Maps are available nowadays for us humans with few exceptions, however, maps suitable for mobile robots rarely exists. In addition, to relate sensor readings to a map requires that the map content and the observation is compatible, i.e. different robots may require different maps for the same area. This book addresses some of the fundamental problems related to mobile robot navigation (registration, localisation and mapping) using cameras as the primary sensor input. Small salient regions (local visual features) are extracted from each camera image, where each region can be seen as a fingerprint. Many fingerprint matches implicates a high likelihood that they corresponding images originate from a similar location, which is a central property utilised in this work.

  • 23.
    Andreasson, Henrik
    et al.
    Örebro University, School of Science and Technology.
    Bouguerra, Abdelbaki
    Örebro University, School of Science and Technology.
    Åstrand, Björn
    Rögnvaldsson, Thorsteinn
    Örebro University, School of Science and Technology.
    Gold-fish SLAM: an application of SLAM to localize AGVs2012In: Proceedings of the International Conference on Field and Service Robotics (FSR), July 2012., 2012Conference paper (Other academic)
    Abstract [en]

    The main focus of this paper is to present a case study of a SLAM solution for Automated Guided Vehicles (AGVs) operating in real-world industrial environ- ments. The studied solution, called Gold-fish SLAM, was implemented to provide localization estimates in dynamic industrial environments, where there are static landmarks that are only rarely perceived by the AGVs. The main idea of Gold-fish SLAM is to consider the goods that enter and leave the environment as temporary landmarks that can be used in combination with the rarely seen static landmarks to compute online estimates of AGV poses. The solution is tested and verified in a factory of paper using an eight ton diesel-truck retrofitted with an AGV control sys- tem running at speeds up to 3 meters per second. The paper includes also a general discussion on how SLAM can be used in industrial applications with AGVs.

  • 24.
    Andreasson, Henrik
    et al.
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    6D scan registration using depth-interpolated local image features2010In: Robotics and Autonomous Systems, ISSN 0921-8890, E-ISSN 1872-793X, Vol. 58, no 2, p. 157-165Article in journal (Refereed)
    Abstract [en]

    This paper describes a novel registration approach that is based on a combination of visual and 3D range information.To identify correspondences, local visual features obtained from images of a standard color camera are compared and the depth of matching features (and their position covariance) is determined from the range measurements of a 3D laserscanner. The matched depth-interpolated image features allows to apply registration with known correspondences.We compare several ICP variants in this paper and suggest an extension that considers the spatial distance betweenmatching features to eliminate false correspondences. Experimental results are presented in both outdoor and indoor environments. In addition to pair-wise registration, we also propose a global registration method that registers allscan poses simultaneously.

  • 25.
    Ansheden, Caroline
    Örebro University, School of Science and Technology.
    Processförbättring för tillverkandet av specialbalk2010Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work has been conducted for Corus Byggsystem AB. The company is located in Halmstad and manufactures profile claddings and purlins from sheet metal. The company also offers the customers professional advice and creates optimal solutions.

    In the production there is a press brake that manufactures purlins. This work station has neither efficient production or is ergonomically correct. The material and purlins are lifted manually by the workers and in some cases over the head. For heavy work, it is extremely important to apply an ergonomic approach, both to improve security for the workers and to increase the manufacturing volume. The focus was therefore on how to improve the workplace ergonomically to result in a safe workplace with efficient manufacturing results.

    The method that was mainly used in this project was David G. Ullmans The Mechanical Design Process and Fredy Olssons Primärkonstruktion and Principkonstruktion. Also SVID’s Design Process has been used as support.

  • 26.
    Arafat, Yeasin
    et al.
    Office of the President of the General Assembly United Nations, New York, USA.
    Hellström, Thomas
    Umeå University, Umeå, Sweden.
    Rashid, Jayedur
    Örebro University, School of Science and Technology.
    Parameterized sensor model and an approach for measuring goodness of robotic maps2010Conference paper (Refereed)
    Abstract [en]

    Map building is a classical problem in mobile and au tonomous robotics, and sensor models is a way to interpret raw sensory information, especially for building maps. In this paper we propose a parameterized sensor model, and optimize map goodness with respect to these parameters. A new approach, measuring the goodness of maps without a handcrafted map of the actual environment is introduced and evaluated. Three different techniques; statistical anal ysis, derivative of images, and comparison of binary maps have been used as estimates of map goodness. The results show that the proposed sensor model generates better maps than a standard sensor model. However, the proposed ap proach of measuring goodness of maps does not improve the results as much as expected.

  • 27.
    Arnesson, Frida
    Örebro University, School of Science and Technology.
    WORK METHOD TO SIMPLIFY TRANSFER OF 3D MODELS TO ANSYS FOR ANALYSIS AT ATLAS COPCO ROCK DRILLS AB2011Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 28.
    Arvidsson, Erik
    Örebro University, School of Science and Technology.
    Energiförbrukning för putsade, odränerade träregelväggar i fuktigt respektive torrt tillstånd2009Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In recent years, moisture damages have been noticed in rendered, undrained stud walls. The design is built on the principle one-stage tightening which means that there is no air gap in the construction. The damages have occurred when water has permeated through the rendering in leaking connections and fittings for windows, doors, canopies, balconies, terraces and awnings. Behind the plaster carrier, which consists of either polystyrene or rigid mineral wool, plasterboard has often been used as a wind protection barrier. In many cases the wind protection barrier and the underlying wooden studs have been exposed to mould and in some cases even rot. It has been shown that damp in the structure is difficult to dry out.

    The aim of the thesis has been to examine how the energy consumption is affected when this type of construction is damp, partly because energy is required to dry up damp, partly because the insulation ability for a material decreases when it is affected by moisture.

    Previous research and relevant literature has been used in this thesis, to provide: A comprehensive picture of the problem, an explanation for the calculations used and an understanding of the conclusions drawn.

    The energy consumption has been calculated for 1 m2 wall area on two types of wall designs. The calculations have been performed in both dry and damp condition. To calculate the energy consumption in damp condition, three different types of calculation models have been used in three different ways. Since no measurements have been made, the calculations are to some extent based on assumed values.

    The amount of damp that have entered the structure has, according to the calculation models used, been shown to produce small differences in energy consumption compared to the dry structure. The main problem for these types of walls seems instead to be the growth of microorganisms. Nevertheless, the microorganisms seem not to have affected the indoor environment in any significant manner.

  • 29.
    Arvidsson, Erik
    et al.
    Örebro University, School of Science and Technology.
    Larsson, Tord
    Örebro University, School of Science and Technology.
    Stridh, Göran
    Örebro University, School of Science and Technology.
    Energiförluster i partiellt fuktiga enstegstätade ytterväggskonstruktioner: tema: fasader och fönster2009In: Bygg & teknik, ISSN 0281-658X, no 8, p. 28-32Article in journal (Other academic)
  • 30.
    Arwidsson, Zandra
    Örebro University, School of Science and Technology.
    Organic complexing agents for remediation of heavy metal contaminated soil2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Soil washing of heavy metal contaminated soil may be enhanced by the addition of synthetic chelators. Since many of these chelators may imply stress to soil organisms and are poorly biodegraded, identification and evaluation of effective biodegradable or recyclable chelators (synthetic and/or naturally produced) is of great interest. The efficiency of biodegradable synthetic chelators was evaluated both in bench- (0.3 kg) and meso- (10 kg) scale. Results demonstrated that the solubilization of copper, lead, and zinc was similar in bench- and meso-scale systems, which indicated that these systems could be used in a technical scale. However, the arsenic extraction in meso-scale system, were non-conclusive. Due to the high cost involved in the purchase of synthetic chelating agents, recycling of the solutions is of great interest, and this was achieved in five consecutive washing cycles. Considering the economy of a full-scale process, recycling of complexing solutions with sulfide addition at each cycle, both at the 100 mM-level, appears feasible. Naturally derived chelators were produced by saprotrophic fungi and through alkaline degradation of humic substances and cellulose. The results demonstrated that these types of complexing agents are not as effective as the synthetic chelators. In the fungal systems, desorption of metals was related to production of organic complexing acids, but mainly to the pH-decrease. Nonetheless, in some systems, formation of soluble complexes was indicated (copper). Enhancement of copper, lead, and zinc release with the use of alkaline leachates from wood and peat appeared possible. Since these agents have a natural origin and are derived from rather cheap raw material, recycling is not an issue.

     

    List of papers
    1. Remediation of Metal Contaminated Soil by Organic Metabolites from Fungi I—Production of Organic Acids
    Open this publication in new window or tab >>Remediation of Metal Contaminated Soil by Organic Metabolites from Fungi I—Production of Organic Acids
    Show others...
    2008 (English)In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 205, no 1-4, p. 215-226Article in journal (Refereed) Published
    Abstract [en]

    Investigations were made on living strains offungi in a bioremediation process of three metal (lead)contaminated soils. Three saprotrophic fungi (Aspergillusniger, Penicillium bilaiae, and a Penicillium sp.) wereexposed to poor and rich nutrient conditions (no carbonavailability or 0.11 M D-glucose, respectively) andmetal stress (25 μM lead or contaminated soils) for5 days. Exudation of low molecular weight organicacids was investigated as a response to the metal andnutrient conditions. Main organic acids identified wereoxalic acid (A. niger) and citric acid (P. bilaiae).Exudation rates of oxalate decreased in response tolead exposure, while exudation rates of citrate were lessaffected. Total production under poor nutrient conditionswas low, except for A. niger, for which nosignificant difference was found between the poor andrich control. Maximum exudation rates were 20 μmoloxalic acid g^−1 biomass h^−1 (A. niger) and 20 μmolcitric acid g^−1 biomass h^−1 (P. bilaiae), in the presenceof the contaminated soil, but only 5 μmol organic acidsg^−1 biomass h^−1, in total, for the Penicillium sp. Therewas a significant mobilization of metals from the soilsin the carbon rich treatments and maximum release ofPb was 12% from the soils after 5 days. This was notsufficient to bring down the remaining concentration tothe target level 300 mg kg^−1 from initial levels of 3,800,1,600, and 370 mg kg^−1in the three soils. Target levelsfor Ni, Zn, and Cu, were 120, 500, and 200 mg kg^−1,respectively, and were prior to the bioremediationalready below these concentrations (except for Cu Soil1). However, maximum release of Ni, Zn, and Cu was28%, 35%, and 90%, respectively. The release of metalswas related to the production of chelating acids, but alsoto the pH-decrease. This illustrates the potential to usefungi exudates in bioremediation of contaminated soil.Nonetheless, the extent of the generation of organicacids is depending on several processes and mechanismsthat need to be further investigated.

    Place, publisher, year, edition, pages
    Berlin, Germany: Springer, 2008
    Keywords
    Bioremediation, Citric acid, Fungi, Lead, Organic acids, Oxalic acid
    National Category
    Natural Sciences Environmental Sciences
    Research subject
    Environmental Chemistry
    Identifiers
    urn:nbn:se:oru:diva-11843 (URN)10.1007/s11270-009-0067-z (DOI)000272851000016 ()2-s2.0-75049083063 (Scopus ID)
    Available from: 2010-09-15 Created: 2010-09-15 Last updated: 2017-12-12Bibliographically approved
    2. Remediation of Metal-Contaminated Soil by Organic Metabolites from Fungi II-Metal Redistribution
    Open this publication in new window or tab >>Remediation of Metal-Contaminated Soil by Organic Metabolites from Fungi II-Metal Redistribution
    2010 (English)In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 207, no 1-4, p. 5-18Article in journal (Refereed) Published
    Abstract [en]

    Exudation of low molecular weight organic acids by fungi was studied in a project focusing on bioremediation of metal-contaminated soils. The production of acids (mainly oxalic and citric acid) as a response to nutrient variations and presence of metals has recently been reported (Arwidsson et al. 2009). A significant release of metals was observed and was related not only to the production of organic acids but also to the resulting pH decrease in the systems. The processes governing the release and redistribution of metals in the soil-water fungus system were the focus of the present continuation of the project, based on observations of Aspergillus niger, Penicillium bilaiae, and a Penicillium sp. The release of lead was 12% from the soil with the second highest initial load (1,600 mg kg(-1)), while the release of copper was 90% from the same soil (140 mg kg(-1)). The dominating mechanism behind the release and subsequent redistribution was the change in pH, going from near neutral to values in the range 2.1-5.9, reflecting the production of organic acids. For some of the systems, the formation of soluble complexes is indicated (copper, at intermediate pH) which favors the metal release. Iron is assumed to play a key role since the amount of secondary iron in the soils is higher than the total load of secondary heavy metals. It can be assumed that most of the heavy metals are initially associated with iron-rich phases through adsorption or coprecipitation. These phases can be dissolved, or associated metals can be desorbed, by a decrease in pH. It would be feasible to further develop a process in technical scale for remediation of metal-contaminated soil, based on microbial metabolite production leading to formation of soluble metal complexes, notably with copper.

    Keywords
    Bioremediation, Fungi, Metals, Oxalic acid, Citric acid
    National Category
    Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-13015 (URN)10.1007/s11270-009-0222-6 (DOI)000274550700002 ()
    Available from: 2011-01-03 Created: 2011-01-03 Last updated: 2018-04-19Bibliographically approved
    3. Leaching of metals from contamined soil with polyhydroxycarboxylic acids of natural origin
    Open this publication in new window or tab >>Leaching of metals from contamined soil with polyhydroxycarboxylic acids of natural origin
    (English)Manuscript (preprint) (Other academic)
    National Category
    Environmental Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-15427 (URN)
    Available from: 2011-04-29 Created: 2011-04-29 Last updated: 2017-10-17Bibliographically approved
    4. Remediation of heavy metal contaminated soil washing residues with amino polycarboxylic acids
    Open this publication in new window or tab >>Remediation of heavy metal contaminated soil washing residues with amino polycarboxylic acids
    Show others...
    2010 (English)In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 173, no 1-3, p. 697-704Article in journal (Refereed) Published
    Abstract [en]

    Removal of Cu, Pb, and Zn by the action of the two biodegradable chelating agents [S,S]-ethylenediaminedisuccinic acid (EDDS) and methylglycinediacetic acid (MGDA), as well as citric acid, was tested. Three soil samples, which had previously been treated by conventional soil washing (water), were utilized in the leaching tests. Experiments were performed in batches (0.3 kg-scale) and with a WTC-mixer system (Water Treatment Construction, 10 kg-scale). EDDS and MGDA were most often equally efficient in removing Cu, Pb, and Zn after 10-60 min. Nonetheless, after 10 d, there were occasionally significant differences in extraction efficiencies. Extraction with citric acid was generally less efficient, however equal for Zn (mainly) after 10 d. Metal removal was similar in batch and WTC-mixer systems, which indicates that a dynamic mixer system could be used in full-scale. Use of biodegradable amino polycarboxylic acids for metal removal, as a second step after soil washing, would release most remaining metals (Cu, Pb and Zn) from the present soils, however only after long leaching time. Thus, a full-scale procedure, based on enhanced metal leaching by amino polycarboxylic acids from soil of the present kind, Would require a pre-leaching step lasting several days in order to be efficient. (C) 2009 Elsevier B.V. All rights reserved.

    Keywords
    Heavy metals, Amino polycarboxylic acids, Soil, Remediation, EDDS, MGDA
    National Category
    Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-13043 (URN)10.1016/j.jhazmat.2009.08.141 (DOI)000273135600098 ()
    Available from: 2011-01-03 Created: 2011-01-03 Last updated: 2018-04-19Bibliographically approved
    5. Recycling of amino polycarboxylic acids in soil washing of heavy metal contaminated soil
    Open this publication in new window or tab >>Recycling of amino polycarboxylic acids in soil washing of heavy metal contaminated soil
    (English)Manuscript (preprint) (Other academic)
    National Category
    Environmental Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-15428 (URN)
    Available from: 2011-04-29 Created: 2011-04-29 Last updated: 2017-10-17Bibliographically approved
    6. Laboratory and pilot scale soil washing of PAH and arsenic from a wood preservation site: Changes in concentration and toxicity
    Open this publication in new window or tab >>Laboratory and pilot scale soil washing of PAH and arsenic from a wood preservation site: Changes in concentration and toxicity
    Show others...
    2009 (English)In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 172, no 2-3, p. 1033-1040Article in journal (Refereed) Published
    Abstract [en]

    Soil washing of a soil with a mixture of both polycyclic aromatic hydrocarbons (PAH) and As was evaluated in laboratory and pilot scale, utilizing both single and mixtures of different additives. The highest level of decontamination was achieved with a combination of 0.213 M of the chelating agent MGDA and 3.2xCMC* of a nonionic, alkyl glucoside surfactant at pH 12 (Ca(OH)2). This combination managed to reach Swedish threshold values within 10 min of treat­ment when performed at elevated temperature (50°C), with initial conta­minant concentrations of As = 105±4 mg/kg and US-EPA PAH16 = 46.0±2.3 mg/kg. The main mechanisms behind the removal were the pH-effect for As and a combina­tion of SOM-ionization as a result of high pH and micellar solu­bilization for PAHs. Implementation of the laboratory results utilizing a pilot scale equipment did not improve the performance, which may be due to the shorter contact time between the washing solution and the particles, or changes in physical characte­ristics of the leaching solution due to the elevated pressure utilized. The ecotox­icological evaluation, Microtox®, demonstrated that all soil washing treatments increased the toxicity of soil leachates, possibly due to in­creased availability of contaminants and toxicity of soil washing solutions to the test organism.

    Place, publisher, year, edition, pages
    Amsterdam: Elsevier, 2009
    Keywords
    Arsenic, Microtox®, PAH, Soil washing, Surfactant
    National Category
    Environmental Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-7988 (URN)10.1016/j.jhazmat.2009.07.092 (DOI)000271980800068 ()19699582 (PubMedID)2-s2.0-71049155866 (Scopus ID)
    Available from: 2009-09-23 Created: 2009-09-23 Last updated: 2017-12-13Bibliographically approved
  • 31.
    Arwidsson, Zandra
    et al.
    Örebro University, School of Science and Technology. SAKAB AB, Kumla, Sweden.
    Allard, Bert
    Örebro University, School of Science and Technology.
    Remediation of Metal-Contaminated Soil by Organic Metabolites from Fungi II-Metal Redistribution2010In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 207, no 1-4, p. 5-18Article in journal (Refereed)
    Abstract [en]

    Exudation of low molecular weight organic acids by fungi was studied in a project focusing on bioremediation of metal-contaminated soils. The production of acids (mainly oxalic and citric acid) as a response to nutrient variations and presence of metals has recently been reported (Arwidsson et al. 2009). A significant release of metals was observed and was related not only to the production of organic acids but also to the resulting pH decrease in the systems. The processes governing the release and redistribution of metals in the soil-water fungus system were the focus of the present continuation of the project, based on observations of Aspergillus niger, Penicillium bilaiae, and a Penicillium sp. The release of lead was 12% from the soil with the second highest initial load (1,600 mg kg(-1)), while the release of copper was 90% from the same soil (140 mg kg(-1)). The dominating mechanism behind the release and subsequent redistribution was the change in pH, going from near neutral to values in the range 2.1-5.9, reflecting the production of organic acids. For some of the systems, the formation of soluble complexes is indicated (copper, at intermediate pH) which favors the metal release. Iron is assumed to play a key role since the amount of secondary iron in the soils is higher than the total load of secondary heavy metals. It can be assumed that most of the heavy metals are initially associated with iron-rich phases through adsorption or coprecipitation. These phases can be dissolved, or associated metals can be desorbed, by a decrease in pH. It would be feasible to further develop a process in technical scale for remediation of metal-contaminated soil, based on microbial metabolite production leading to formation of soluble metal complexes, notably with copper.

  • 32.
    Arwidsson, Zandra
    et al.
    Örebro University, School of Science and Technology.
    Allard, Bert
    Örebro University, School of Science and Technology.
    Elgh-Dalgren, Kristin
    Örebro University, School of Science and Technology.
    van Hees, Patrick
    Örebro University, School of Science and Technology.
    Recycling of amino polycarboxylic acids in soil washing of heavy metal contaminated soilManuscript (preprint) (Other academic)
  • 33.
    Arwidsson, Zandra
    et al.
    SAKAB AB, Kumla, Sweden.
    Elgh-Dalgren, Kristin
    Örebro University, School of Science and Technology.
    Nehrenheim, Emma
    School of Sustainable Development of Society and Technology, Mälardalen University, Västerås, Sweden.
    Odlare, Monica
    School of Sustainable Development of Society and Technology, Mälardalen University, Västerås, Sweden.
    Ribé, Veronica
    School of Sustainable Development of Society and Technology, Mälardalen University, Västerås, Sweden.
    Sjöberg, Ragnar
    Solventic AB, Motala, Sweden.
    von Kronhelm, Tomas
    SAKAB AB, Kumla, Sweden.
    van Hees, Patrick
    Örebro University, School of Science and Technology.
    Allard, Bert
    Örebro University, School of Science and Technology.
    Remediation of soils and sludges containing organic contaminants as well as metals – soil-wash procedures combining biodegradation, chemical complexation and mechanical separation of particulate matter2009Conference paper (Refereed)
    Abstract [en]

    Soil contamination is an urgent issue world wide. More than 83,000 contaminated sites have been identified in Sweden alone, of which approximately some 4,000 require treatment in the near future. Most of the sites carry a mixture of contaminants, metals as well as persistent organics. Most soil remediation efforts are made ex situ, which means that the soil or sludge is dug up and transported to a facility for treatment, or simply for deposition. The aim of the present project is to design a strategy for ex situ treatment of soils with mixed contaminants. A variety of soils and sludges from different sites (around 10), essentially all with organic as well as inorganic (metallic) contaminants, have been selected for experimental studies in laboratory and pilot scale: Military sites (metals, explosives), wood preservation sites (PAHs, As, metals), industrial sites (metals, hydrocarbons, mercury, dioxins and others). Of particular importance in the present study are:

    Metals – Pb, Cu, Zn, Cr, Hg, as well as As Organics – PAHs, nitro aromatics, dioxins

    A number of processes are selected and applied: •Biodegradation - use of commercially available cultures, as well as bacteria cultivated from the contaminated site itself •Mobilisation of organics - use of surface active agents •Mobilisation of metals - use of (1) complexing microbial metabolites produced in the soil (by fungii in paricular), (2) complexing agents generated by degradation of natural organic products (polyhydroxy carboxylic acids), and (3) artificial complexing agents (polyamino carboxylic acids).

    Biodegradation is performed in batches (anaerobic in most cases), while release and mobilisation of contaminants from soil aggregates are achieved during soil-wash performed in a dynamic system where wash solution is forced through the soil under high pressure (the WTC-process). The efficiency of biodegradation and subsequent soil-wash under various conditions is evaluated from chemical analysis, but also by several ecotoxicological tests. Some results are given that illustrates suitable strategies for treatment of mixed contaminated soil from real sites (soil) as well as for treatment of residues from industrial production (sludges etc).

  • 34.
    Arwidsson, Zandra
    et al.
    Örebro University, School of Science and Technology. SAKAB AB, Kumla, Sweden.
    Elgh-Dalgren, Kristin
    Örebro University, School of Science and Technology.
    von Kronhelm, Thomas
    SAKAB AB, Kumla, Sweden.
    Sjoberg, Ragnar
    Solvent AB, Motala, Sweden.
    Allard, Bert
    Örebro University, School of Science and Technology.
    van Hees, Patrick A. W.
    Örebro University, School of Science and Technology.
    Remediation of heavy metal contaminated soil washing residues with amino polycarboxylic acids2010In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 173, no 1-3, p. 697-704Article in journal (Refereed)
    Abstract [en]

    Removal of Cu, Pb, and Zn by the action of the two biodegradable chelating agents [S,S]-ethylenediaminedisuccinic acid (EDDS) and methylglycinediacetic acid (MGDA), as well as citric acid, was tested. Three soil samples, which had previously been treated by conventional soil washing (water), were utilized in the leaching tests. Experiments were performed in batches (0.3 kg-scale) and with a WTC-mixer system (Water Treatment Construction, 10 kg-scale). EDDS and MGDA were most often equally efficient in removing Cu, Pb, and Zn after 10-60 min. Nonetheless, after 10 d, there were occasionally significant differences in extraction efficiencies. Extraction with citric acid was generally less efficient, however equal for Zn (mainly) after 10 d. Metal removal was similar in batch and WTC-mixer systems, which indicates that a dynamic mixer system could be used in full-scale. Use of biodegradable amino polycarboxylic acids for metal removal, as a second step after soil washing, would release most remaining metals (Cu, Pb and Zn) from the present soils, however only after long leaching time. Thus, a full-scale procedure, based on enhanced metal leaching by amino polycarboxylic acids from soil of the present kind, Would require a pre-leaching step lasting several days in order to be efficient. (C) 2009 Elsevier B.V. All rights reserved.

  • 35.
    Arwidsson, Zandra
    et al.
    Örebro University, School of Science & Technology, Örebro, Sweden; SAKAB AB, Kumla, Sweden.
    Johansson, Emma M.
    Örebro University, School of Science and Technology.
    von Kronhelm, Thomas
    SAKAB AB, Kumla Sweden.
    Allard, Bert
    Örebro University, School of Science and Technology.
    van Hees, Patrick A. W.
    Örebro University, School of Science and Technology. Eurofins Environment Sweden AB, Lidköping, Sweden.
    Remediation of Metal Contaminated Soil by Organic Metabolites from Fungi I—Production of Organic Acids2008In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 205, no 1-4, p. 215-226Article in journal (Refereed)
    Abstract [en]

    Investigations were made on living strains offungi in a bioremediation process of three metal (lead)contaminated soils. Three saprotrophic fungi (Aspergillusniger, Penicillium bilaiae, and a Penicillium sp.) wereexposed to poor and rich nutrient conditions (no carbonavailability or 0.11 M D-glucose, respectively) andmetal stress (25 μM lead or contaminated soils) for5 days. Exudation of low molecular weight organicacids was investigated as a response to the metal andnutrient conditions. Main organic acids identified wereoxalic acid (A. niger) and citric acid (P. bilaiae).Exudation rates of oxalate decreased in response tolead exposure, while exudation rates of citrate were lessaffected. Total production under poor nutrient conditionswas low, except for A. niger, for which nosignificant difference was found between the poor andrich control. Maximum exudation rates were 20 μmoloxalic acid g^−1 biomass h^−1 (A. niger) and 20 μmolcitric acid g^−1 biomass h^−1 (P. bilaiae), in the presenceof the contaminated soil, but only 5 μmol organic acidsg^−1 biomass h^−1, in total, for the Penicillium sp. Therewas a significant mobilization of metals from the soilsin the carbon rich treatments and maximum release ofPb was 12% from the soils after 5 days. This was notsufficient to bring down the remaining concentration tothe target level 300 mg kg^−1 from initial levels of 3,800,1,600, and 370 mg kg^−1in the three soils. Target levelsfor Ni, Zn, and Cu, were 120, 500, and 200 mg kg^−1,respectively, and were prior to the bioremediationalready below these concentrations (except for Cu Soil1). However, maximum release of Ni, Zn, and Cu was28%, 35%, and 90%, respectively. The release of metalswas related to the production of chelating acids, but alsoto the pH-decrease. This illustrates the potential to usefungi exudates in bioremediation of contaminated soil.Nonetheless, the extent of the generation of organicacids is depending on several processes and mechanismsthat need to be further investigated.

  • 36.
    Arwidsson, Zandra
    et al.
    Örebro University, School of Science and Technology.
    Ålund, Marie
    Örebro University, School of Science and Technology.
    Allard, Bert
    Örebro University, School of Science and Technology.
    Leaching of metals from contamined soil with polyhydroxycarboxylic acids of natural originManuscript (preprint) (Other academic)
  • 37.
    Arwidsson, Zandra
    et al.
    SAKAB AB, Norrtorp, Sweden.
    Ålund, Marie
    SAKAB AB, Norrtorp, Sweden.
    Allard, Bert
    Örebro University, School of Science and Technology.
    Karlsson, Stefan
    Örebro University, School of Science and Technology.
    Metal mobilisation from soils and sediments by hydroxycarboxylic acids of natural origin2011In: 25th International Applied Geochemistry Symposium, 22-26 August, 2011, Rovaniemi, Finland / [ed] Pertti Sarala, V. Juhani Ojala, Marja-Leena Porsanger, 2011, p. 77-77Conference paper (Refereed)
  • 38.
    Arén, Björn
    Örebro University, School of Science and Technology.
    Dimensionering efter hållfasthet av olika slag2009In: Uppfinnaren & konstruktören, ISSN 0284-9682, no 5, p. 32-34Article in journal (Other (popular science, discussion, etc.))
  • 39.
    Arén, Björn
    Örebro University, School of Science and Technology.
    Utveckling - är att se, söka och förverkliga: kursbok i produktutveckling2010 (ed. 1)Book (Other academic)
  • 40.
    Asadi, Sahar
    et al.
    Örebro University, School of Science and Technology.
    Badica, Costin
    University of Craiova, Craiova, Romania.
    Comes, Tina
    Karslruhe Institute of Technology, Karslruhe, Germany.
    Conrado, Claudine
    Thales Research and Technology, Delft, The Nederlands.
    Evers, Vanessa
    University of Amsterdam, Amsterdam, The Netherlands.
    Groen, Frans
    University of Amsterdam, Amsterdam, The Netherlands.
    Illie, Sorin
    University of Craiova, Craiova, Romania.
    Steen Jensen, Jan
    Danish Emergency Management Agency (DEMA), Birkerød, Denmark.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Milan, Bianca
    DCMR, Delft, The Netherlands.
    Neidhart, Thomas
    Space Applications Services, Zaventem, Belgium.
    Nieuwenhuis, Kees
    Thales Research and Technology, Delft, The Netherlands.
    Pashami, Sepideh
    Örebro University, School of Science and Technology.
    Pavlin, Gregor
    Thales Research and Technology, Delft, The Netherlands.
    Pehrsson, Jan
    Prolog Development Center, Brøndby Copenhagen, Denmark.
    Pinchuk, Rani
    Space Applications and Services, Zaventem, Belgium.
    Scafes, Mihnea
    University of Craiova, Craiova, Romania.
    Schou-Jensen, Leo
    DCMR, Brøndby Copenhagen, Denmark.
    Schultmann, Frank
    Karslruhe Institute of Technology, Karlsruhe, Germany.
    Wijngaards, Niek
    Thales Research and Technology, Delft, the Netherlands.
    ICT solutions supporting collaborative information acquisition, situation assessment and decision making in contemporary environmental management problems: the DIADEM approach2011In: Proceedings of the 25th EnviroInfo Conference "Environmental Informatics", Herzogenrath: Shaker Verlag, 2011, p. 920-931Conference paper (Refereed)
    Abstract [en]

    This paper presents a framework of ICT solutions developed in the EU research project DIADEM that supports environmental management with an enhanced capacity to assess population exposure and health risks, to alert relevant groups and to organize efficient response. The emphasis is on advanced solutions which are economically feasible and maximally exploit the existing communication, computing and sensing resources. This approach enables efficient situation assessment in complex environmental management problems by exploiting relevant information obtained from citizens via the standard communication infrastructure as well as heterogeneous data acquired through dedicated sensing systems. This is achieved through a combination of (i) advanced approaches to gas detection and gas distribution modelling, (ii) a novel service-oriented approach supporting seamless integration of human-based and automated reasoning processes in large-scale collaborative sense making processes and (iii) solutions combining Multi-Criteria Decision Analysis, Scenario-Based Reasoning and advanced human-machine interfaces. This paper presents the basic principles of the DIADEM solutions, explains how different techniques are combined to a coherent decision support system and briefly discusses evaluation principles and activities in the DIADEM project.

  • 41.
    Asadi, Sahar
    et al.
    Örebro University, School of Science and Technology.
    Pashami, Sepideh
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    TD Kernel DM+V: time-dependent statistical gas distribution modelling on simulated measurements2011In: Olfaction and Electronic Nose: proceedings of the 14th International Symposium on Olfaction and Electronic Nose (ISOEN) / [ed] Perena Gouma, Springer Science+Business Media B.V., 2011, p. 281-282Conference paper (Refereed)
    Abstract [en]

    To study gas dispersion, several statistical gas distribution modelling approaches have been proposed recently. A crucial assumption in these approaches is that gas distribution models are learned from measurements that are generated by a time-invariant random process. While a time-independent random process can capture certain fluctuations in the gas distribution, more accurate models can be obtained by modelling changes in the random process over time. In this work we propose a time-scale parameter that relates the age of measurements to their validity for building the gas distribution model in a recency function. The parameters of the recency function define a time-scale and can be learned. The time-scale represents a compromise between two conflicting requirements for obtaining accurate gas distribution models: using as many measurements as possible and using only very recent measurements. We have studied several recency functions in a time-dependent extension of the Kernel DM+V algorithm (TD Kernel DM+V). Based on real-world experiments and simulations of gas dispersal (presented in this paper) we demonstrate that TD Kernel DM+V improves the obtained gas distribution models in dynamic situations. This represents an important step towards statistical modelling of evolving gas distributions.

  • 42. Ax, Erika
    et al.
    Sjögren, Per
    Lind, P. Monica
    Lampa, Erik
    Salihovic, Samira
    Örebro University, School of Science and Technology.
    van Bavel, Bert
    Örebro University, School of Science and Technology.
    Lind, Lars
    Dietary pattern affects blood levels of environmental pollutants in elderly Swedish men and women2011In: Annals of Nutrition and Metabolism, ISSN 0250-6807, E-ISSN 1421-9697, Vol. 58, no Suppl. 3, p. 59-60Article in journal (Refereed)
  • 43.
    Axelsson, Erik
    et al.
    Örebro University, School of Science and Technology.
    André, Samuel
    Örebro University, School of Science and Technology.
    Studie av smörjsystem2011Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal of this work is to investigate the lubrication system on two exposed joints on a Boomer E2C. The request for the thesis comes from Atlas Copco Rock Drills AB, Örebro, which also manufactures the machine.

    Today Atlas Copco Rock Drills AB has a grease lubrication system that secures the function of the joints. The task is to summarize and evaluate the current systems and to find new solutions that would be able to replace or partially replace the current system. Information was gathered from documents, construction drawings and conversations with engineers at the company. Solutions and ideas have been formed by meeting stock suppliers and searching for articles. Brainstorming has been used in order to find new solutions.

    The investigation has shown that there are problems with the current solution in terms of hose failures and downtime in the field. Atlas Copco AB also expresses that there is a lack of documentation and knowledge regarding the lubrication system. After the various article searches it became clear that research and knowledge in the area with heavy duty, oscillating and grease lubricated joints is insufficient. The design is often done with the help of experience and with the mindset "it has worked before."

    When the solutions and ideas have been compared, this has been done by using AHP (Analytic Hierarchy Process). This method compares the criteria that must be fulfilled by the solutions and then calculates the best one.

    The results show that a lubrication-free solution would theoretically be preferable. This would be produced by a modern polymer and supplemented with an inner seal and an outer protection. Atlas Copco is recommended to test the various proposals to be able to decide which the best solution for the application is.

     

  • 44. Baskar, Sushmitha
    et al.
    Baskar, Ramanathan
    Routh, Joyanto
    Örebro University, School of Science and Technology.
    Biogenic evidences of moonmilk deposition in the Mawmluh cave, Meghalaya, India2011In: Geomicrobiology Journal, ISSN 0149-0451, E-ISSN 1521-0529, Vol. 28, no 3, p. 252-265Article in journal (Refereed)
    Abstract [en]

    Moonmilk, a microcrystalline secondary cave deposit, actively forms on the floor of Krem Mawmluh - a limestone cave in Meghalaya, Northeastern India. Due to the abundance of micrite and calcified microbial filaments, we hypothesize that these deposits form as a result of ongoing microbial interactions. Consistent with this idea, we report electron microscopic and microbiological evidences for the biological origin of moonmilk in Krem Mawmluh. Scanning electron microscopy indicated abundant calcified microbial filaments, needle calcite, fibre calcites (micro-fibre and nano-fibre calcite crystals), biofilm and microbial filaments in the moonmilk. The total viable culturable microbes showed high population densities for microbes in the moonmilk and moonmilk pool waters. In vitro culture experiments, confirmed the capability of many of the isolated strains to precipitate calcite and some of the identified isolates belonged to the Bacillus sp. and Actinomycetes. These results clearly support the biogenic nature of the deposits.

  • 45.
    Bazzan, Ana L. C.
    et al.
    UFRGS, Porto Alegre, Brazil.
    de Oliveira, Denise
    UFRGS, Porto Alegre, Brazil.
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    Nagel, Kai
    TU Berlin.
    To adapt or not to adapt: consequences of adapting driver and traffic light agents2008In: Adaptive agents and multi-agent systems III: adaptation and multi-agent learning : 5th, 6th, and 7th European Symposium,ALAMAS 2005-2007on Adaptive and Learning Agents and Multi-Agent Systems : revised selected papers / [ed] Karl Tuyls, Ann Nowe, Zahia Guessoum, New York: Springer , 2008, p. 1-14Conference paper (Refereed)
    Abstract [en]

    One way to cope with the increasing traffic demand is to integrate standard solutions with more intelligent control measures. However, the result of possible interferences between intelligent control or information provision tools and other components of the overall traffic system is not easily predictable. This paper discusses the effects of integrating co-adaptive decision-making regarding route choices (by drivers) and control measures (by traffic lights). The motivation behind this is that optimization of traffic light control is starting to be integrated with navigation support for drivers. We use microscopic, agent-based modelling and simulation, in opposition to the classical network analysis, as this work focuses on the effect of local adaptation. In a scenario that exhibits features comparable to real-world networks, we evaluate different types of adaptation by drivers and by traffic lights, based on local perceptions. In order to compare the performance, we have also used a global level optimization method based on genetic algorithms.

  • 46.
    Bazzan, Ana L. C.
    et al.
    UFRGS, Porto Alegre, Brazil.
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    Re-routing agents in an abstract traffic scenario2008In: Advances in artificial intelligence: SBIA 2008 / [ed] Gerson Zaverucha, Augusto Loureiro da Costa, Berlin: Springer , 2008, p. 63-72Conference paper (Refereed)
    Abstract [en]

    Human drivers may perform replanning when facing traffic jams or when informed that there are expected delays on their planned routes. In this paper, we address the effects of drivers re-routing, an issue that has been ignored so far. We tackle re-routing scenarios, also considering traffic lights that are adaptive, in order to test whether such a form of co-adaptation may result in interferences or positive cumulative effects. An abstract route choice scenario is used which resembles many features of real world networks. Results of our experiments show that re-routing indeed pays off from a global perspective as the overall load of the network is balanced. Besides, re-routing is useful to compensate an eventual lack of adaptivity regarding traffic management.

  • 47.
    Bazzan, Ana L.
    et al.
    UFRGS, Porto Alegre, Brazil.
    Klügl, FranziskaÖrebro University, School of Science and Technology.
    Multi-agent systems for traffic and transportation engineering2009Collection (editor) (Other academic)
  • 48.
    Bazzan, Ana Lucia
    et al.
    Universidade Federal Rio Grande do Sul (UFRGS), Rio Grande do Sul, Brazil .
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    Introduction to Intelligent Systems in Traffic and Transportation2013Book (Refereed)
    Abstract [en]

    Urban mobility is not only one of the pillars of modern economic systems, but also a key issue in the quest for equality of opportunity, once it can improve access to other services. Currently, however, there are a number of negative issues related to traffic, especially in mega-cities, such as economical issues (cost of opportunity caused by delays), environmental (externalities related to emissions of pollutants), and social (traffic accidents). Solutions to these issues are more and more closely tied to information and communication technology. Indeed, a search in the technical literature (using the keyword ``urban traffic" to filter out articles on data network traffic) retrieved the following number of articles (as of December 3, 2013): 9,443  (ACM Digital Library), 26,054 (Scopus), and 1,730,000 (Google Scholar). Moreover, articles listed in the ACM query relate to conferences as diverse as MobiCom, CHI, PADS, and AAMAS. This means that  there is a big and diverse community of computer scientists and computer engineers who tackle research that is connected to the development of intelligent traffic and transportation systems. It is also possible to see that this community is growing, and that research projects are getting more and more interdisciplinary. To foster the cooperation among the involved communities, this book aims at  giving a broad introduction into the basic but relevant concepts related to transportation systems, targeting researchers and practitioners from computer science and information technology. In addition, the second part of the book gives a panorama of some of the most exciting and newest technologies, originating in computer science and computer engineering, that are now being employed in projects related to car-to-car communication, interconnected vehicles, car navigation, platooning, crowd sensing and sensor networks, among others. This material will also be of interest to engineers and researchers from the traffic and transportation community.

  • 49.
    Berg, A. H.
    et al.
    Örebro University, School of Science and Technology.
    Westerlund, L.
    Olsson, Per-Erik
    Örebro University, School of Science and Technology.
    Regulation of Arctic char (Salvelinus alpinus) egg shell proteins and vitellogenin during reproduction and in response to 17beta-estradiol and cortisol2004In: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, Vol. 135, no 3, p. 276-285Article in journal (Refereed)
    Abstract [en]

    Estrogens induce both vitellogenin (Vtg) and egg shell (zona pellucida; ZP) protein synthesis in salmonids. However, while Vtg is strictly under estrogenic control, recent reports suggest that additional mechanisms are involved in ZP protein synthesis. During sexual maturation both estrogen and glucocorticoid levels increase in the circulation of female fish. As glucocorticoids have been shown to interfere with Vtg induction in fish we investigated whether cortisol (F) had similar effects on ZP regulation. In the present study we determined both the natural variation in Vtg and ZP during an annual reproductive cycle in female Arctic char (Salvelinus alpinus), and the effect of co-treatment of juvenile Arctic char with 17beta-estradiol (E2) and F. During sexual maturation the expression of Vtg and ZP correlated to plasma levels of E2 and F. Determination of Vtg and ZP protein levels following co-treatment with E2 and F showed that F antagonized E2 induction of Vtg. However, F was observed to potentiate the expression of ZP protein in the same fish. These results indicate that in Arctic char Vtg and ZP proteins are not regulated by the same mechanisms and suggest that ZP protein expression does not necessarily imply exposure to estrogenic compounds alone, and may thus not be ideally suited as a biomarker of exposure to estrogenic compounds.

  • 50.
    Berg, Håkan
    et al.
    Örebro University, School of Science and Technology.
    Modig, Carina
    Olsson, Per-Erik
    Örebro University, School of Science and Technology.
    17beta-estradiol induced vitellogenesis is inhibited by cortisol at the post-transcriptional level in Arctic char (Salvelinus alpinus)2004In: Reproductive biology and endocrinology, ISSN 1477-7827, Vol. 2, p. 62-Article in journal (Refereed)
    Abstract [en]

    This study was performed to investigate stress effects on the synthesis of egg yolk precursor, vitellogenin (Vtg) in Arctic char (Salvelinus alpinus). In particular the effect of cortisol (F) was determined since this stress hormone has been suggested to interfere with vitellogenesis and is upregulated during sexual maturation in teleosts. Arctic char Vtg was purified and polyclonal antibodies were produced in order to develop tools to study regulation of vitellogenesis. The Vtg antibodies were used to develop an enzyme-linked immunosorbent assay. The corresponding Vtg cDNA was cloned from a hepatic cDNA library in order to obtain DNA probes to measure Vtg mRNA expression. Analysis of plasma from juvenile Arctic char, of both sexes, exposed to different steroids showed that production of Vtg was induced in a dose dependent fashion by 17beta-estradiol (E2), estrone and estriol. Apart from estrogens a high dose of F also upregulated Vtg. In addition, F, progesterone (P) and tamoxifen were tested to determine these compounds ability to modulate E2 induced Vtg synthesis at both the mRNA and protein level. Tamoxifen was found to inhibit E2 induced Vtg mRNA and protein upregulation. P did not alter the Vtg induction while F reduced the Vtg protein levels without affecting the Vtg mRNA levels. Furthermore the inhibition of Vtg protein was found to be dose dependent. Thus, the inhibitory effect of F on Vtg appears to be mediated at the post-transcriptional level.

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