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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 universitet, Akademin för naturvetenskap och teknik.
    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 technique2010Inngår i: Genes, Chromosomes and Cancer, ISSN 1045-2257, E-ISSN 1098-2264, Vol. 49, nr 11, s. 1035-1045Artikkel i tidsskrift (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Hammarström, Niklas
    Örebro universitet, Akademin för naturvetenskap och teknik.
    UTVÄRDERING OCH UTVECKLING AV TRANSPORTFIXTURER FÖR BAKAXLAR:  2011Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Examensarbetet har genomförts i samarbete med Meritor HVS AB i Lindesberg som tillverkar fram- och bakhjulsaxlar till buss- och lastbilsindustrin. Projektet behandlar de fixturer som används vid transport av bakhjulsaxlar. Målet med arbetet var att utveckla en ny transportfixtur som passar majoriteten av deras bakaxelmodeller och som förebygger skador vid transport.

    Projektet har genomförts enligt metodiken systematisk konstruktion som beskrivs enligt Johannesson, Persson och Petterssons (2004). Systematisk konstruktion kan delas in i fem steg: produktspecificering, konceptgenerering, utvärdering och val av koncept, detaljkonstruktion samt slutkonstruktion.

    De problem som Meritor har med transportfixturerna är att de i hög grad slits och att skyddsbeläggningarna inte håller. Det finns för projektet 30 aktuella bakaxelmodeller som skall kunna transporteras med samma fixtur. Meritor använder sig av en grundfixtur och diverse nödlösningar för att kunna hantera alla modeller. De nya fixturkoncepten begränsas av de nuvarande stålrackens dimensioner och fixturernas positioner i dem.

    Utifrån de konceptförslag som tagits fram i arbetet, fördes de två mest lämpade koncepten vidare till slutkonstruktion. Det första konceptet, T-fixturen, bygger på den fixtur som används idag och är således ett förbättringsförslag. Förbättringarna består av en ökad anläggningsyta, bättre skyddsbeläggning samt vikt- och hållfasthetsoptimeringar. Det andra konceptet, pinnfixturen, bygger även den på samma grundfixtur men använder sig av två öglor som finns på varje axelmodell. Genom att placera axelns öglor över två pinnar i fixturen uppnås en total fixering av axeln.

  • 3.
    Ahmed, Muhammad Rehan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Compliance Control of Robot Manipulator for Safe Physical Human Robot Interaction2011Doktoravhandling, monografi (Annet vitenskapelig)
    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 universitet, Akademin för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Semi-active compliant robot enabling collision safety for human robot interaction2010Inngår i: 2010 International Conference on Mechatronics and Automation (ICMA), IEEE, 2010, s. 1932-1937Konferansepaper (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Static and dynamic collisionsafety for human robot interaction using magneto-rheological fluid based compliant robot manipulator2010Inngår i: IEEE international conference on robotics and biomimetics (ROBIO), 2010, IEEE conference proceedings, 2010, s. 370-375Konferansepaper (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Static collision analysis of semi active compliant robot for safe human robot interaction2010Inngår i: Proceedings of the 12th Mechatronics Forum Biennial International Conference, IWF Institute of Machine tools and manufacturing , 2010, s. 220-227Konferansepaper (Fagfellevurdert)
  • 7.
    Ahmed, Muhammad Rehan
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Two link compliant robot manipulator for physical human robot collision safety2012Inngår i: Biomedical Engineering Systems and Technologies / [ed] Ana Fred, Joaquim Filipe, Hugo Gamboa, Springer, 2012Konferansepaper (Fagfellevurdert)
  • 8.
    Ahmed, Rehan M.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Ananiev, Anani V.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Compliant motion control for safe human robot interaction2009Inngår i: Robot motion and control 2009 / [ed] Krzysztof R. Kozłowski, Berlin: Springer , 2009, s. 265-274Konferansepaper (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Ananiev, Anani V.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Kalaykov, Ivan G.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Safe robot with reconfigurable compliance/stiffness actuation2009Inngår i: Proceedings of ASME/IFToMM International Conference on Reconfigurable Mechanisms and Robots. ReMAR'2009 / [ed] J. S. Dai, M. Zoppi, X. W. Kong, IEEE, 2009, s. 633-638Konferansepaper (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Kalaykov, Ivan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Ananiev, Anani
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Modeling of magneto rheological fluid actuator enabling safe human-robot interaction2008Inngår i: IEEE International Conference on Emerging Technologies and Factory Automation, 2008. ETFA 2008, 2008, s. 974-979Konferansepaper (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Käll, Mikael
    Green’s tensor calculations of plasmon resonances of single holes and hole pairs in thin gold films2008Inngår i: New Journal of Physics, ISSN 1367-2630, E-ISSN 1367-2630, Vol. 10, nr 105004Artikkel i tidsskrift (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Coaching by gaming: an instructor perspective of game-based vocational training2011Licentiatavhandling, med artikler (Annet vitenskapelig)
    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

  • 13.
    Alklind Taylor, Anna-Sofia
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Introducing the coaching cycle: a coaching by gaming perspective of serious gamingManuskript (preprint) (Annet vitenskapelig)
    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 universitet, Akademin för naturvetenskap och teknik.
    Backlund, Per
    University of Skövde, Skövde, Sweden.
    Letting the students create and the teacher play: expanding the roles in serious gaming2011Inngår i: 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, s. 63-70Konferansepaper (Annet vitenskapelig)
    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 universitet, Akademin för naturvetenskap och teknik.
    Uranbrytning i Sverige: ett miljöproblem?2009Konferansepaper (Fagfellevurdert)
  • 16.
    Allard, Bert
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Bäckström, Mattias
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Häller, Sara
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Panova, Elena
    St Petersburgs universitet, St Petersburg, Ryssland.
    Grawunder, Anja
    Friedrich Sciller Univ., Jena, Germany.
    Karlsson, Stefan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Water chemistry and trace metal concentrations in an acidic alum shale pit lake: effects of liming2011Inngår i: 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, s. 503-508Konferansepaper (Fagfellevurdert)
  • 17.
    Allard, Bert
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Sartz, Lotta
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Karlsson, Stefan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Bäckström, Mattias
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Metal releases from historic sulphidic mine site (Ljusnarsberg, Sweden): mobilization and attenuation processes2008Konferansepaper (Fagfellevurdert)
  • 18.
    Almestrand, Lovisa
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Passivhus i Örebro län: Undersökning av marknaden för fastighetsägare2009Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Detta examensarbete syftar till att undersöka vilken kunskap som fastighetsägare har om passivhus samt om det finns någon marknad för detta koncept i Örebro län.

    Miljö- och klimatproblemen i världen blir allt större och ett resultat av detta är den ständigt cirkulerande debatten om passivhus.  Lågenergihus är en nödvändig lösning för att energianvändningen ska kunna minskas, då bostadssektorn står för cirka 40 % av Sveriges totala energianvändning. Passivhus är en utveckling av lågenergihuset som byggs utan konventionellt uppvärmningssystem och har en låg energianvändning. Asplunds Bygg i Örebro bygger nu våren 2009 de första passivhusen i Örebro.

    Examensarbetet inleddes med att fastighetsägare kontaktades och intervjuer bokades. De muntliga intervjuerna genomfördes under en fyra veckors period på respektive fastighetsägares kontor. En egen fördjupning i ämnet gjordes parallellt med intervjuerna genom att studera passivhus i bl.a. litteratur, artiklar och på Internet. Resultatet av intervjuerna sammanställdes, jämfördes och analyserades utifrån syftet med arbetet.

    Fastighetsägarna är positivt inställda till konceptet och anser att energifrågan är viktig, men kunskapen kring passivhus hos vissa är bristfällig. Avslutningsvis konstateras att utifrån resultatet av intervjuerna så verkar det som att det finns en framtida marknad för passivhus i Örebro län.

    Nyckelord: passivhus, lågenergihus, energianvändning, ventilationssystem, värmeåtervinning, tjock isolering.  

  • 19.
    Andersson, Emelie
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Jämförande studie avseende svenska byggregler och den europeiska standarden eurokoder: Inriktning husbyggnad och betongkonstruktion2009Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    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 universitet, Akademin för naturvetenskap och teknik.
    Rotander, Anna
    Örebro universitet, Akademin för naturvetenskap och teknik.
    von Kronhelm, Thomas
    SAKAB.
    Berggren, Anna
    Analycen AB.
    Ivarsson, Per
    Analycen AB.
    Hollert, Henner
    RWTH Aachen university.
    Engwall, Magnus
    Örebro universitet, Akademin för naturvetenskap och teknik.
    AhR agonist and genotoxicant bioavailability in a PAH-contaminated soil undergoing biological treatment2009Inngår i: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 16, nr 5, s. 521-530Artikkel i tidsskrift (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Quartz in Swedish iron foundries: exposure and cancer risk2012Doktoravhandling, med artikler (Annet vitenskapelig)
    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.

  • 22.
    Andreasson, Henrik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Camera based navigation by mobile robots: local visual feature based localisation and mapping2009Bok (Annet vitenskapelig)
    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 universitet, Akademin för naturvetenskap och teknik.
    Bouguerra, Abdelbaki
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Åstrand, Björn
    Rögnvaldsson, Thorsteinn
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Gold-fish SLAM: an application of SLAM to localize AGVs2012Inngår i: Proceedings of the International Conference on Field and Service Robotics (FSR), July 2012., 2012Konferansepaper (Annet vitenskapelig)
    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 universitet, Akademin för naturvetenskap och teknik.
    Lilienthal, Achim J.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    6D scan registration using depth-interpolated local image features2010Inngår i: Robotics and Autonomous Systems, ISSN 0921-8890, E-ISSN 1872-793X, Vol. 58, nr 2, s. 157-165Artikkel i tidsskrift (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Processförbättring för tillverkandet av specialbalk2010Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Examensarbetet genomfördes åt företaget Corus Byggsystem AB. Ett företag placerat i Halmstad som tillverkar profilplåt och lättbalk till tak och fasader. Företaget erbjuder även god rådgivning och skapar optimala lösningar för kunden.

    I företagets produktion finns det en maskin som pressar specialbalkar. Denna arbetsplats är varken produktionseffektiv eller ergonomiskt riktig då materialet och balkarna lyftes manuellt, i vissa fall även över huvudet. På tunga arbetsplatser är det oerhört viktigt att se över ergonomin, både för att förbättra säkerheten och för att öka produktionsvolymen. Fokus lades därför vid att förbättra arbetsplatsen ergonomiskt för att resultera i ett säkert och produktionseffektivt resultat.

    Som metod har tre olika varianter använts. Främst Ullmans metod The Mechanical Design Process och Fredy Olssons Primär- och Principkonstruktion. Även SVID’s Designprocess har funnits väl till pass.

  • 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 universitet, Akademin för naturvetenskap och teknik.
    Parameterized sensor model and an approach for measuring goodness of robotic maps2010Konferansepaper (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    WORK METHOD TO SIMPLIFY TRANSFER OF 3D MODELS TO ANSYS FOR ANALYSIS AT ATLAS COPCO ROCK DRILLS AB2011Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
  • 28.
    Arvidsson, Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Energiförbrukning för putsade, odränerade träregelväggar i fuktigt respektive torrt tillstånd2009Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    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 universitet, Akademin för naturvetenskap och teknik.
    Larsson, Tord
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Stridh, Göran
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Energiförluster i partiellt fuktiga enstegstätade ytterväggskonstruktioner: tema: fasader och fönster2009Inngår i: Bygg & teknik, ISSN 0281-658X, nr 8, s. 28-32Artikkel i tidsskrift (Annet vitenskapelig)
  • 30.
    Arwidsson, Zandra
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Organic complexing agents for remediation of heavy metal contaminated soil2009Doktoravhandling, med artikler (Annet vitenskapelig)
    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.

     

  • 31.
    Arwidsson, Zandra
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik. SAKAB AB, Kumla, Sweden.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Remediation of Metal-Contaminated Soil by Organic Metabolites from Fungi II-Metal Redistribution2010Inngår i: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 207, nr 1-4, s. 5-18Artikkel i tidsskrift (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Elgh-Dalgren, Kristin
    Örebro universitet, Akademin för naturvetenskap och teknik.
    van Hees, Patrick
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Recycling of amino polycarboxylic acids in soil washing of heavy metal contaminated soilManuskript (preprint) (Annet vitenskapelig)
  • 33.
    Arwidsson, Zandra
    et al.
    SAKAB AB, Kumla, Sweden.
    Elgh-Dalgren, Kristin
    Örebro universitet, Akademin för naturvetenskap och teknik.
    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 universitet, Akademin för naturvetenskap och teknik.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Remediation of soils and sludges containing organic contaminants as well as metals – soil-wash procedures combining biodegradation, chemical complexation and mechanical separation of particulate matter2009Konferansepaper (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik. SAKAB AB, Kumla, Sweden.
    Elgh-Dalgren, Kristin
    Örebro universitet, Akademin för naturvetenskap och teknik.
    von Kronhelm, Thomas
    SAKAB AB, Kumla, Sweden.
    Sjoberg, Ragnar
    Solvent AB, Motala, Sweden.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    van Hees, Patrick A. W.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Remediation of heavy metal contaminated soil washing residues with amino polycarboxylic acids2010Inngår i: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 173, nr 1-3, s. 697-704Artikkel i tidsskrift (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    von Kronhelm, Thomas
    SAKAB AB, Kumla Sweden.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    van Hees, Patrick A. W.
    Örebro universitet, Akademin för naturvetenskap och teknik. Eurofins Environment Sweden AB, Lidköping, Sweden.
    Remediation of Metal Contaminated Soil by Organic Metabolites from Fungi I—Production of Organic Acids2008Inngår i: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 205, nr 1-4, s. 215-226Artikkel i tidsskrift (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Ålund, Marie
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Leaching of metals from contamined soil with polyhydroxycarboxylic acids of natural originManuskript (preprint) (Annet vitenskapelig)
  • 37.
    Arwidsson, Zandra
    et al.
    SAKAB AB, Norrtorp, Sweden.
    Ålund, Marie
    SAKAB AB, Norrtorp, Sweden.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Karlsson, Stefan
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Metal mobilisation from soils and sediments by hydroxycarboxylic acids of natural origin2011Inngår i: 25th International Applied Geochemistry Symposium, 22-26 August, 2011, Rovaniemi, Finland / [ed] Pertti Sarala, V. Juhani Ojala, Marja-Leena Porsanger, 2011, s. 77-77Konferansepaper (Fagfellevurdert)
  • 38.
    Arén, Björn
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Dimensionering efter hållfasthet av olika slag2009Inngår i: Uppfinnaren & konstruktören, ISSN 0284-9682, nr 5, s. 32-34Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 39.
    Arén, Björn
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Utveckling - är att se, söka och förverkliga: kursbok i produktutveckling2010 (oppl. 1)Bok (Annet vitenskapelig)
  • 40.
    Asadi, Sahar
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Badica, Costin
    University of Craiova, Craiova, Romania.
    Comes, Tina
    Karslruhe Institute of Technology, Karslruhe, Germany.
    Conrado, Claudine
    Thales Research and Technology, Delft, The Netherlands.
    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 universitet, Akademin för naturvetenskap och teknik.
    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 universitet, Institutionen för naturvetenskap och teknik.
    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 approach2011Inngår i: Proceedings of the 25th EnviroInfo Conference "Environmental Informatics", Herzogenrath: Shaker Verlag, 2011, s. 920-931Konferansepaper (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Pashami, Sepideh
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lilienthal, Achim J.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    TD Kernel DM+V: time-dependent statistical gas distribution modelling on simulated measurements2011Inngår i: 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, s. 281-282Konferansepaper (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    van Bavel, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lind, Lars
    Dietary pattern affects blood levels of environmental pollutants in elderly Swedish men and women2011Inngår i: Annals of Nutrition and Metabolism, ISSN 0250-6807, E-ISSN 1421-9697, Vol. 58, nr Suppl. 3, s. 59-60Artikkel i tidsskrift (Fagfellevurdert)
  • 43.
    Axelsson, Erik
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    André, Samuel
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Studie av smörjsystem2011Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [sv]

     

    Målet med detta arbete är att undersöka smörjsystemet på två utsatta leder på en Boomer E2C. Förfrågan om examensarbetet kommer från Atlas Copco Rock Drills AB i Örebro som också tillverkar maskinen.

    Atlas Copco Rock Drills AB har idag ett fettsmörjningssystem som upprätthåller funktionerna på lederna. Uppgiften är att sammanfatta och utvärdera dagens system samt att finna nya lösningsförslag som skulle kunna ersätta eller delvis ersätta systemet. Information har hämtats från dokumentation, ritningar och samtal med konstruktörer på företaget. Efter att alla förutsättningarna för lederna specificerats så har lösningsförslag sökts. Genom att träffa lagerleverantörer och söka artiklar så har idéer formats. Brainstorming har använts för att kunna se nya lösningar.

    Undersökningen har visat att det finns problem med dagens lösning vad gäller slanghaverier och driftstopp i fält. Atlas Copco AB uttrycker även att kunskapen och dokumentationen angående systemet är otillräckligt. Efter artikelsökning så kan konstateras att forskningen och kunskapen på området med tungt belastade, oscillerande och fettsmörjda leder är liten. Dimensionering sker ofta med hjälp av erfarenhet och med tankesättet ”det har fungerat förut”.

    När lösningsförslagen har jämförts så har detta gjorts genom att använda metoden AHP (Analytic Hierachy Process). Med denna metod så jämför man kriterierna från kravspecifikationen med lösningsförslag så att man matematiskt kan räkna fram ett vinnande lösningsförslag.

    Resultatet visar att en smörjfri lösning skulle teoretiskt vara att föredra. Denna skulle tillverkas av en modern polymer och kompletteras med en inre tätning och ett yttre skydd. Atlas Copco rekommenderas att testa de olika förslagen för att komma fram till vilken som är bäst lämpad för applikationen.

  • 44. Baskar, Sushmitha
    et al.
    Baskar, Ramanathan
    Routh, Joyanto
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Biogenic evidences of moonmilk deposition in the Mawmluh cave, Meghalaya, India2011Inngår i: Geomicrobiology Journal, ISSN 0149-0451, E-ISSN 1521-0529, Vol. 28, nr 3, s. 252-265Artikkel i tidsskrift (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Nagel, Kai
    TU Berlin.
    To adapt or not to adapt: consequences of adapting driver and traffic light agents2008Inngår i: 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, s. 1-14Konferansepaper (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Re-routing agents in an abstract traffic scenario2008Inngår i: Advances in artificial intelligence: SBIA 2008 / [ed] Gerson Zaverucha, Augusto Loureiro da Costa, Berlin: Springer , 2008, s. 63-72Konferansepaper (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Multi-agent systems for traffic and transportation engineering2009Collection/Antologi (Annet vitenskapelig)
  • 48.
    Bazzan, Ana Lucia
    et al.
    Universidade Federal Rio Grande do Sul (UFRGS), Rio Grande do Sul, Brazil .
    Klügl, Franziska
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Introduction to Intelligent Systems in Traffic and Transportation2013Bok (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Westerlund, L.
    Olsson, Per-Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Regulation of Arctic char (Salvelinus alpinus) egg shell proteins and vitellogenin during reproduction and in response to 17beta-estradiol and cortisol2004Inngår i: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, Vol. 135, nr 3, s. 276-285Artikkel i tidsskrift (Fagfellevurdert)
    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 universitet, Akademin för naturvetenskap och teknik.
    Modig, Carina
    Olsson, Per-Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    17beta-estradiol induced vitellogenesis is inhibited by cortisol at the post-transcriptional level in Arctic char (Salvelinus alpinus)2004Inngår i: Reproductive biology and endocrinology, ISSN 1477-7827, Vol. 2, s. 62-Artikkel i tidsskrift (Fagfellevurdert)
    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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