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  • 51.
    Berg, Håkan
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Scherbak, Nikolai
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Liimatta, Harri
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Hoffmann, Erik
    Karlsson, Johnny
    Olsson, Per-Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Characterization of antibodies for quantitative determination of spiggin protein levels in male and female three-spined stickleback (Gasterosteus aculeatus)2009Inngår i: Reproductive Biology and Endocrinology, ISSN 1477-7827, E-ISSN 1477-7827, Vol. 7, nr 1, artikkel-id 46Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Spiggin is an adhesive glycoprotein produced in the kidney of sticklebacks during the breeding season and is subsequently secreted into the urinary bladder from where it is employed for nest building. Since the production of the protein has been shown to be under androgenic control, spiggin has been suggested to be a useful biomarker for androgenic substances in the environment. In this study, two polyclonal spiggin antibodies based on synthetic peptides and one polyclonal antibody directed against native spiggin have been characterized. The antibodies ability to identify spiggin was investigated by quantitative immunoassay. For both peptide antibodies the quantification range was determined to be between 1 and 80 ng spiggin and determination of renal spiggin levels from immature and mature males displayed a 15-fold increase in total spiggin content of the kidney resulting in a 6-fold increase in male kidney weight due to hypertrophy. The kidney somatic index (KSI) was found to correlate well with the total renal spiggin content and therefore it appears that KSI in sticklebacks could be used as an initial method to identify substances displaying androgenic effects. Furthermore, western blot analysis revealed that the polyclonal antibodies recognize different spiggin isoforms and that spiggin can be detected in the urinary bladder and kidney of both males and female sticklebacks. In order to develop a quantitative detection method for native spiggin it is necessary to produce a standard that can be used in a bioassay. Due to the adhesive and polymerization characteristics of spiggin the protein is difficult to use as a standard in bioassays. So far spiggin has been shown to exist in at least 14 isoforms, all of which contain polymerization domains. To overcome the solubility problem we have produced recombinant spiggin gamma, with only one polymerization domain, that can be expressed in E. coli. Western blot analysis demonstrated that the polyclonal antibodies were able to detect recombinant spiggin gamma protein in bacterial cell lysate, suggesting that it may be developed into a useful source of standard spiggin to be used for quantitative determination of androgen induced spiggin production in sticklebacks.

  • 52. Berger, Urs
    et al.
    Kaiser, Mary A.
    Kärrman, Anna
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Barber, Jonathan L.
    van Leeuwen, Stefan P. J.
    Recent developments in trace analysis of poly- and perfluoroalkyl substances2011Inngår i: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 400, nr 6, s. 1625-1635Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

     Recent developments, improvements, and trends in the ultra-trace determination of per- and polyfluoroalkyl substances (PFASs) in environmental and human samples are highlighted and the remaining challenges and uncertainties are outlined and discussed. Understanding the analytical implications of such things as adsorption of PFASs to surfaces, effects of differing matrices, varying PFAS isomer response factors, potential bias effects of sampling, sample preparation, and analysis is critical to measuring highly fluorinated compounds at trace levels. These intricate analytical issues and the potential consequences of ignoring to deal with them correctly are discussed and documented with examples. Isomer-specific analysis and the development of robust multi-chemical methods are identified as topical trends in method development for an ever-increasing number of PFASs of environmental and human interest. Ultimately, the state-of-the-art of current analytical method accuracy is discussed on the basis of results from interlaboratory comparison studies.

  • 53.
    Bergman, Christian
    Örebro universitet, Akademin för naturvetenskap och teknik.
    How Lean is Swedish Product Development?: A study of Lean practices in large Swedish companies2010Independent thesis Advanced level (degree of Master (Two Years)), 30 poäng / 45 hpOppgave
    Abstract [en]

    This master’s thesis aims to capture the essence of Lean Product Development and to evaluate to what extent Swedish companies have implemented lean principles. Previous studies in this field exemplify how methods are used by already lean practitioners, and there is a lack ofknowledge about the extent to which lean in is used in product development in industry.

    A literature review reveals a number of principles and perspectives; 5 Lean principles, 13 Lean Product Development principles, 14 Lean Management principles and 4 critical factors for Lean (or Knowledge-based) Product Development. These principles and perspectives were the starting point in developing the survey questions.

    The survey of 26 questions was sent to 67 large Swedish companies (more than 249 employees) working with product development and design. The response rate of 39 per centwas unusually high for this type of internet survey.

    The main results of the survey are that Lean methods and tools are rather extensively used in product development, but the culturehas yet not permeated the entire company. The workload of the product developmentdepartment is too high and a structured method for organizational learning is lacking.

    Recommendations for the studied companies are to reduce the workload and increase thetime for reflection, learning and process improvement. Also, the capability to implement strategies can be improved.

  • 54.
    bergman, martin
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Sinnenas Rum - Ytor för bastumiljö2010Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [sv]

    I denna rapport kan läsaren följa händelseförloppet med framtagningen av en fysisk mood-board med tillhörande grafisk manual. Läsaren kommer att få en allmän förståelse för hur det semantiska hos en produkt påverkar dess användare samt hur detta påverkar produktens resultat på marknaden. I projektet pressenteras en tämligen oanvänd metod som, kortfattat; syftar till att ta vara på en målgrupps specifika känslor om exempelvis en produkt för att göra denna mer optimerad. I detta projekt handlade det mer om att ta fram specifika strukturer vilka tillslut kom att leda till ett antal speciellt utvalda ytor och material åt företaget Tylö® AB. Materialet tillsammans med speciella ytor skall komma att skapa en mer elegant känsla i deras kommande sortiment. Metoden som används för att nå fram till resultatet heter Kansei Engineering.

  • 55. Billnert, R.
    et al.
    Oberstedt, S.
    Andreotti, E.
    Hult, M.
    Marissens, G.
    Oberstedt, Andreas
    Örebro universitet, Akademin för naturvetenskap och teknik.
    New information on the characteristics of 1 in. x 1 in. cerium bromide scintillation detectors2011Inngår i: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 647, nr 1, s. 94-99Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In view of highly demanded new and accurate data on prompt gamma-ray emission in nuclear fission a major part of investigations is directed towards the selection of suitable detector systems. Here we have studied a new type of crystal scintillation detectors made from cerium bromide (CeBr(3)). For the first time a full characterization of such a detector is presented in terms of energy resolution, pulse-height linearity, intrinsic activity and intrinsic timing resolution. In particular the latter one is very important for prompt fission gamma-ray studies, because the presence of fast neutrons, emitted in fission too, requires the time-of-flight method for their discrimination. The energy resolution has been found to be comparable to that of cerium-doped LaCl(3):Ce detectors at an efficiency comparable to the one of a LaBr(3):Ce detector of the same size. The intrinsic activity of the CeBr(3) crystal was observed to be much lower compared to lanthanum halide crystals. The intrinsic timing resolution of a coaxial 1 in. x 1 in. sized detector was measured relative to that of a previously characterized LaCl(3):Ce detector and found to be (326 +/- 7) Ps at (60)Co energies, which is in between those of a LaBr(3):Ce and a LaCl(3):Ce detector of same size. (C) 2011 Elsevier B.V. All rights reserved.

  • 56.
    Birgersson, Evert
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Oberstedt, Andreas
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Oberstedt, Stephan
    Hambsch, Franz-Josef
    Properties of the reaction 238U(n, f) at the vibrational resonances2009Inngår i: Nuclear Physics A, ISSN 0375-9474, E-ISSN 1873-1554, Vol. 817, nr 1-4, s. 1-34Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Recent fission cross-section calculations for the reaction 238U(n, f ), based on an extended statistical model, predict a significant change of fission fragment properties, such as the mean mass by A = 1.5 and a notable increase in total kinetic energy in the region of the vibrational resonance at an incident neutron energy En = 0.9 MeV. This model includes individual fission cross-sections by the asymmetric standard 1 (S1) and standard 2 (S2) as well as the symmetric super-long (SL) mode. In order to verify the model predictions, a dedicated experiment on 238U has been carried out to measure fission-fragment mass yield distributions for incident neutron energies from En = 2.0 MeV down to 0.9 MeV, where the fission characteristics at the vibrational resonance at En = 0.9 MeV were investigated for the first time. The previously reported distinct structure in the angular anisotropy around En = 1.2 and 1.6 MeV wasobserved at En = 0.9 MeV as well. The predicted large changes in fission fragment mass yield and total kinetic energy could not be confirmed. In the resonance the mean total kinetic energy is only about 0.5 MeV higher than at En = 1.8 MeV. At the same time, a slight decrease of the mean heavy fragment mass was observed, probably indicating a slightly increased contribution of the S1 fission mode.

  • 57.
    Birkelöf, Jonas
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Framtagning av demonstratorer2009Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    På Alfred Nobelmuseet i Karlskoga finns en avdelning som kallas Fiffiga huset. Där finns många experiment som besökare kan prova på, samt montrar som visar hur olika tekniska och maskinella apparater fungerar. Till utställningen och öppnandet sommaren 2009 ville de ha två nya demonstratorer. I rapporten kallas dem för reaktionstidsväggen och baklängesprataren. Reaktionstidsväggen skulle mäta besökarens reaktionstid genom att tryckknappar, med inbyggda dioder som slumpvis tänds, trycks ned i rätt ordning. Baklängesprataren skulle spela in besökarens tal och sedan spela upp det baklänges. Tanken var att besökaren skulle försöka prata baklänges och få det att låta rätt vid uppspelning. Arbetet gick ut på att bygga dessa demonstratorer och montera dem i Fiffiga huset. Reaktionstidsväggen styrdes med hjälp av en mikroprocessor ATMega16 från Atmel. Dess jobb var att läsa av knapptryckningar samt skicka information till dioder och display. Även baklängesprataren skulle styras med hjälp av mikroprocessorn ATMega16. En enkel mikrofonförstärkare samt filter till högtalarna skulle anslutas till processorn. Det inbyggda minnet skulle inte räcka till så ett extern minne behövde anslutas.Endast reaktionstidsväggen hann bli färdig inom projektets ramar eftersom all gammal elektronik som medföljde från Nobelmuseet var komplex, samt att många kortslutningar och avbrott gjorde felsökning till en tidskrävande procedur.

  • 58.
    Björk, Robert G.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik. Dept Plant & Environm Sci, Univ Gothenburg, Gothenburg, Sweden.
    Ernfors, Maria
    Dept Plant & Environm Sci, Univ Gothenburg, Gothenburg, Sweden.
    Sikström, Ulf
    Forestry Res Inst Sweden Skogforsk, Uppsala, Sweden.
    Nilsson, Mats B.
    Dept Forest Ecol & Management, Swedish Univ Agr Sci SLU, Umeå, Sweden.
    Andersson, Mats X.
    Dept Plant & Environm Sci, Univ Gothenburg, Gothenburg, Sweden.
    Rutting, Tobias
    Dept Plant & Environm Sci, Univ Gothenburg, Gothenburg, Sweden.
    Klemedtsson, Leif
    Dept Plant & Environm Sci, Univ Gothenburg, Gothenburg, Sweden.
    Contrasting effects of wood ash application on microbial community structure, biomass and processes in drained forested peatlands2010Inngår i: FEMS Microbiology Ecology, ISSN 0168-6496, E-ISSN 1574-6941, Vol. 73, nr 3, s. 550-562Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The effects of wood ash application on soil microbial processes were investigated in three drained forested peatlands, which differed in nutrient status and time since application. Measured variables included the concentrations of soil elements and phospholipid fatty acids (PLFAs), net nitrogen (N) mineralization, nitrification and denitrification enzyme activity, potential methane (CH(4)) oxidation, CH(4) production and microbial respiration kinetics. Wood ash application had a considerable influence on soil element concentrations. This mirrored a decrease in the majority of the microbial biomarkers by more than one-third in the two oligotrophic peatlands, although the microbial community composition was not altered. The decreases in PLFAs coincided with reduced net ammonification and net N mineralization. Other measured variables did not change systematically as a result of wood ash application. No significant changes in microbial biomass or processes were found in the mesotrophic peatland, possibly because too little time (1 year) had elapsed since the wood ash application. This study suggests that oligotrophic peatlands can be substantially affected by wood ash for a period of at least 4 years after application. However, within 25 years of the wood ash application, the microbial biomass seemed to have recovered or adapted to enhanced element concentrations in the soil.

  • 59.
    Björkblom, Carina
    et al.
    Laboratory of Aquatic Pathobiology, Åbo Akademi University, Turku, Finland.
    Högfors, Eva
    Laboratory of Aquatic Pathobiology, Åbo Akademi University, Turku, Finland.
    Salste, Lotta
    Laboratory of Organic Chemistry, Åbo Akademi University, Turku, Finland.
    Bergelin, Eija
    Laboratory of Wood and Paper Chemistry, Åbo Akademi University, Turku, Finland.
    Olsson, Per-Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Katsiadaki, Ioanna
    Cefas Weymouth Laboratory, Weymouth, United Kingdom.
    Wiklund, Tom
    Laboratory of Aquatic Pathobiology, Åbo Akademi University, Turku, Finland.
    Estrogenic and androgenic effects of municipal wastewater effluent on reproductive endpoint biomarkers in three-spined stickleback (Gasterosteus aculeatus)2009Inngår i: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 28, nr 5, s. 1063-1071Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Municipal wastewater treatment plants have been associated with the release of endocrine-disrupting chemicals, which consequently lead to alterations of reproductive function in aquatic organisms. The three-spined stickleback (Gasterosteus aculeatus) has quantifiable biomarkers for assessment of both estrogen (vitellogenin) and androgen (spiggin) activity, which makes this species very valuable in the research of endocrine disruption. The estrogenic and androgenic biomarkers were used for evaluating exposure effects of municipal wastewater effluent. We evaluated the effects of 17alpha-ethinylestradiol (EE2), 17alpha-methyltestosterone (MT), and wastewater effluents on induction of vitellogenin and spiggin production, gonadosomatic index, hepatosomatic index, nephrosomatic index, plasma steroid levels, and histopathology. Adult female and male sticklebacks were exposed to 20 ng/L of EE2, 10 microg/L of MT, and wastewater effluent (10, 50, and 80% of original concentration) in a flow-through system for an exposure of one week and an extended exposure of four weeks. Chemical analyses of the steroids were done for verification of exposure concentrations and presence in the used wastewater. Our results show that municipal wastewater effluent exerts estrogenic action on three-spined stickleback as observed by elevated vitellogenin levels in exposed fish, corresponding to the effect seen in fish exposed to EE2. Furthermore, wastewater and EE2 exerted similar histopathological effects on testis of exposed fish. Although domestic effluent is suspected to have a high content of natural androgens, no obvious androgenic effect of wastewater was observed in the present study.

  • 60.
    Björkman, Mats P.
    et al.
    Dept Plant & Environm Sci, Univ Gothenburg, Gothenburg, Sweden.
    Morgner, Elke
    Fac Biosci Fisheries & Econ, Dept Arctic & Marine Biol, Univ Tromso, Tromso, Norway; Dept Arctic Biol, Univ Ctr Svalbard, Longyearbyen, Norway.
    Cooper, Elisabeth J.
    Fac Biosci Fisheries & Econ, Dept Arctic & Marine Biol, Univ Tromso, Tromso, Norway.
    Elberling, Bo
    Univ Ctr Svalbard, Longyearbyen, Norway; Dept Geog & Geol, Univ Copenhagen, Copenhagen, Denmark.
    Klemedtsson, Leif
    Dept Plant & Environm Sci, Univ Gothenburg, Gothenburg, Sweden.
    Björk, Robert G.
    Örebro universitet, Akademin för naturvetenskap och teknik. Dept Plant & Environm Sci, Univ Gothenburg, Gothenburg, Sweden.
    Winter carbon dioxide effluxes from Arctic ecosystems: an overview and comparison of methodologies2010Inngår i: Global Biogeochemical Cycles, ISSN 0886-6236, E-ISSN 1944-9224, Vol. 24, s. GB3010-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The winter CO(2) efflux from subnivean environments is an important component of annual C budgets in Arctic ecosystems and consequently makes prediction and estimations of winter processes as well as incorporations of these processes into existing models important. Several methods have been used for estimating winter CO(2) effluxes involving different assumptions about the snowpack, all aiming to quantify CO(2) production. Here, four different methods are compared and discussed: (1) measurements with a chamber on the snow surface, F(snow), (2) chamber measurements directly on the soil, F(soil), after snow removal, (3) diffusion measurements, F(2-point), within the snowpack, and (4) a trace gas technique, F(SF6), with multiple gas sampling within the snowpack. According to measurements collected from shallow and deep snow cover in High Arctic Svalbard and subarctic Sweden during the winter of 2007-2008, the four methods differ by up to two orders of magnitude in their estimates of total winter emissions. The highest mean winter CO(2) effluxes, 7.7-216.8 mg CO(2) m(-2) h(-1), were observed using F(soil) and the lowest values, 0.8-12.6 mg CO(2) m(-2) h(-1), using F(SF6). The F(snow) and F(2-point) methods were both within the lower range, 2.1-15.1 and 6.8-11.2 mg CO(2) m(-2) h(-1), respectively. These differences result not only from using contrasting methods but also from the differences in the assumptions within the methods when quantifying CO(2) production and effluxes to the atmosphere. Because snow can act as a barrier to CO(2), F(soil) is assumed to measure soil production, whereas F(SF6), F(snow), and F(2-point) are considered better approaches for quantifying exchange processes between the soil, snow, and the atmosphere. This study indicates that estimates of winter CO(2) emissions may vary more as a result of the method used than as a result of the actual variation in soil CO(2) production or release. This is a major concern, especially when CO(2) efflux data are used in climate models or in carbon budget calculations, thus highlighting the need for further development and validation of accurate and appropriate techniques.

  • 61.
    Borissov, Alexei
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Janecek, Jakob
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Pecora, Federico
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Towards a network robot system for object identification and localization in RoboCup@Home2008Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper describes a realization of a network robot system for autonomous object localization and identification. Developing a ``Lost \& Found'' capability, the use of which can be envisaged in a wide range of applicative domains including domestic assistive scenarios, is a challenging task for current AI and robotic technology. Indeed, this task is currently one of the core challenges within the RoboCup@Home competition. A number of approaches for implementing a robust and general Lost \& Found functionality are feasible. In this paper we present a solution which integrates state-of-the-art intelligent software, robotic and sensory components in a distributed network of cooperating modules. This article describes the design and implementation of the system, provides a preliminary experimental evaluation and discusses the applicability of our approach to the RoboCup@Home challenge.

  • 62.
    Bouguerra, Abdelbaki
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Andreasson, Henrik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lilienthal, Achim J.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Åstrand, Björn
    Halmstad University, Halmstad, Sweden.
    Rögnvaldsson, Thorsteinn
    Halmstad University, Halmstad, Sweden.
    An autonomous robotic system for load transportation2009Inngår i: 2009 IEEE Conference on Emerging Technologies & Factory Automation (EFTA 2009), New York: IEEE conference proceedings, 2009, s. 1563-1566Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents an overview of an autonomous robotic material handling system. The goal of the system is to extend the functionalities of traditional AGVs to operate in highly dynamic environments. Traditionally, the reliable functioning of AGVs relies on the availability of adequate infrastructure to support navigation. In the target environments of our system, such infrastructure is difficult to setup in an efficient way. Additionally, the location of objects to handle are unknown, which requires that the system be able to detect and track object positions at runtime. Another requirement of the system is to be able to generate trajectories dynamically, which is uncommon in industrial AGV systems.

  • 63.
    Bouguerra, Abdelbaki
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Andreasson, Henrik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lilienthal, Achim J.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Åstrand, Björn
    Halmstad University.
    Rögnvaldsson, Thorsteinn
    Halmstad University, Sweden.
    MALTA: a system of multiple autonomous trucks for load transportation2009Inngår i: Proceedings of the 4th European conference on mobile robots (ECMR) / [ed] Ivan Petrovic, Achim J. Lilienthal, 2009, s. 93-98Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents an overview of an autonomousrobotic material handling system. The goal of the system is toextend the functionalities of traditional AGVs to operate in highlydynamic environments. Traditionally, the reliable functioning ofAGVs relies on the availability of adequate infrastructure tosupport navigation. In the target environments of our system,such infrastructure is difficult to setup in an efficient way.Additionally, the location of objects to handle are unknown,which requires that the system be able to detect and track objectpositions at runtime. Another requirement of the system is to beable to generate trajectories dynamically, which is uncommon inindustrial AGV systems.

  • 64.
    Bouguerra, Abdelbaki
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Karlsson, Lars
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Monitoring the execution of robot plans using semantic knowledge2008Inngår i: Robotics and Autonomous Systems, ISSN 0921-8890, E-ISSN 1872-793X, Vol. 56, nr 11, s. 942-954Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Even the best laid plans can fail, and robot plans executed in real world domains tend to do so often. The ability of a robot to reliably monitor the execution of plans and detect failures is essential to its performance and its autonomy. In this paper, we propose a technique to increase the reliability of monitoring symbolic robot plans. We use semantic domain knowledge to derive implicit expectations of the execution of actions in the plan, and then match these expectations against observations. We present two realizations of this approach: a crisp one, which assumes deterministic actions and reliable sensing, and uses a standard knowledge representation system (LOOM); and a probabilistic one, which takes into account uncertainty in action effects, in sensing, and in world states. We perform an extensive validation of these realizations through experiments performed both in simulation and on real robots.

  • 65.
    Brax, Christoffer
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Anomaly detection in the surveillance domain2011Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    In the post September 11 era, the demand for security has increased in virtually all parts of the society. The need for increased security originates from the emergence of new threats which differ from the traditional ones in such a way that they cannot be easily defined and are sometimes unknown or hidden in the “noise” of daily life.

    When the threats are known and definable, methods based on situation recognition can be used find them. However, when the threats are hard or impossible to define, other approaches must be used. One such approach is data-driven anomaly detection, where a model of normalcy is built and used to find anomalies, that is, things that do not fit the normal model. Anomaly detection has been identified as one of many enabling technologies for increasing security in the society.

    In this thesis, the problem of how to detect anomalies in the surveillance domain is studied. This is done by a characterisation of the surveillance domain and a literature review that identifies a number of weaknesses in previous anomaly detection methods used in the surveillance domain. Examples of identified weaknesses include: the handling of contextual information, the inclusion of expert knowledge and the handling of joint attributes. Based on the findings from this study, a new anomaly detection method is proposed. The proposed method is evaluated with respect to detection performance and computational cost on a number datasets, recorded from real-world sensors, in different application areas of the surveillance domain. Additionally, the method is also compared to two other commonly used anomaly detection methods. Finally, the method is evaluated on a dataset with anomalies developed together with maritime subject matter experts. The conclusion of the thesis is that the proposed method has a number of strengths compared to previous methods and is suitable foruse in operative maritime command and control systems.

  • 66.
    Bushnell, Eric A C
    et al.
    University of Windsor, Windsor, ON, N9B 3P4, Canada.
    Erdtman, Edvin
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Llano, Jorge
    University of Windsor, Windsor, ON, N9B 3P4, Canada.
    Eriksson, Leif A.
    National University of Ireland, Galway, University Road, Galway, Ireland.
    Gauld, James W.
    University of Windsor, Windsor, ON, N9B 3P4, Canada.
    Computational insights into the first branching point in porphyrin biosynthesis: decarboxylation of ring D in URO–III by Uroporphyrinogen–III DecarboxylaseManuskript (preprint) (Annet vitenskapelig)
  • 67.
    Bushnell, Eric A. C.
    et al.
    Department of Chemistry and Biochemistry, University of Windsor, Windsor ON, Canada.
    Erdtman, Edvin
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Llano, Jorge
    Department of Chemistry and Biochemistry, University of Windsor, Windsor ON, Canada.
    Eriksson, Leif A.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Gauld, James W.
    Department of Chemistry and Biochemistry, University of Windsor, Windsor ON, Canada.
    The first branching point in porphyrin biosynthesis: a systematic docking, molecular dynamics and quantum mechanical/molecular mechanical study of substrate binding and mechanism of uroporphyrinogen-III decarboxylase2011Inngår i: Journal of Computational Chemistry, ISSN 0192-8651, E-ISSN 1096-987X, Vol. 32, nr 5, s. 822-834Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In humans, uroporphyrinogen decarboxylase is intimately involved in the synthesis of heme, where the decarboxylation of the uroporphyrinogen-III occurs in a single catalytic site. Several variants of the mechanistic proposal exist; however, the exact mechanism is still debated. Thus, using an ONIOM quantum mechanical/molecular mechanical approach, the mechanism by which uroporphyrinogen decarboxylase decarboxylates ring D of uroporphyrinogen-III has been investigated. From the study performed, it was found that both Arg37 and Arg50 are essential in the decarboxylation of ring D, where experimentally both have been shown to be critical to the catalytic behavior of the enzyme. Overall, the reaction was found to have a barrier of 10.3 kcal mol−1 at 298.15 K. The rate-limiting step was found to be the initial protontransfer from Arg37 to the substrate before the decarboxylation. In addition, it has been found that several key interactions exist between the substrate carboxylate groups and backbone amides of various activesite residues as well as several other functional groups.

  • 68. Byttner, S.
    et al.
    Rögnvaldsson, Thorsteinn
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Svensson, Magnus
    Volvo, Gothenburg, Sweden.
    Consensus self-organized models for fault detection (COSMO)2011Inngår i: Engineering applications of artificial intelligence, ISSN 0952-1976, E-ISSN 1873-6769, Vol. 24, nr 5, s. 833-839Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Methods for equipment monitoring are traditionally constructed from specific sensors and/or knowledge collected prior to implementation on the equipment. A different approach is presented here that builds up knowledge over time by exploratory search among the signals available on the internal field bus system and comparing the observed signal relationships among a group of equipment that perform similar tasks. The approach is developed for the purpose of increasing vehicle uptime, and is therefore demonstrated in the case of a city bus and a heavy duty truck. However, it also works fine for smaller mechatronic systems like computer hard-drives. The approach builds on an onboard self-organized search for models that capture relations among signal values on the vehicles' data buses, combined with a limited bandwidth telematics gateway and an off-line server application where the parameters of the self-organized models are compared. The presented approach represents a new look at error detection in commercial mechatronic systems, where the normal behavior of a system is actually found under real operating conditions, rather than the behavior observed in a number of laboratory tests or test-drives prior to production of the system. The approach has potential to be the basis for a self-discovering system for general purpose fault detection and diagnostics. (c) 2011 Elsevier Ltd. All rights reserved.

  • 69.
    Bäckström, Mattias
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Sartz, Lotta
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Mixing of acid rock drainage with alkaline ash leachates: fate and immobilisation of trace elements2011Inngår i: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 222, nr 1-4, s. 377-389Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Acid rock drainage (ARD) from mine waste dumps often contains ferrous iron, sulphate and high concentrations of trace elements detrimental to the environment. Future costs will be enormous if the problem is not treated today. Simple, low maintenance, cost-effective methods for remediation of historical mine sites are therefore desired. In this study several mine waters were mixed with an alkaline ash leachtes in order to study the fate of the trace elements from both the mine waters (Cd, Cu, Pb, Zn, Ni and Co) and the ash leachates (Cr and Mo). It was found that the addition of ash water will precipitate hydrous ferric oxides (HFO) and hydrous aluminium oxides (HAO) and thereby inducing trace element sorption and co precipitation. It is also clear that the composition of the formed HFO/HAO mix determines the efficiency of the sorption for different trace elements. It is apparent that the amount of precipitating iron will determine the effectiveness of the removal of the trace elements. Sorption occurred much earlier (often one pH unit or more) in the system with high iron concentrations compared to the systems with lower iron concentrations. Removal of cadmium and zinc is difficult below pH 8 if the amount of precipitates is low. Using ash for generation of alkaline water may be a problem with regards to chromium and molybdenum. It is, however, possible to avoid problems with molybdenum by keeping the final pH around 7 and chromium(VI) from the ash water will be reduced into chromium(III) and precipitated as the hydroxide in the presence of iron(II) from the mine waters.

    The results imply that it is possible to also use fly ashes in alkaline leach beds in order to neutralize ARD followed by precipitation and sorption of trace elements.

  • 70.
    Bäckström, Mattias
    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.
    Allard, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Prevention of ARD through stabilization of waste rock with alkaline by-products: results from a meso-scale experiment2010Inngår i: Mina Water & Innovative Thinking: proceedings 2010 / [ed] Wolkersdorfer, C. & Freund, A, Nova Scotia, Canada: Cape Breton University Press , 2010, s. 559-563Konferansepaper (Fagfellevurdert)
  • 71.
    Bäckström, Mattias
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Sädbom, Stefan
    Risk assessment of historical mine waste using chemical analysis and ocular mineral/rock classification: a comparison2008Inngår i: ICAM 2008: 9th International Congress for Applied Mineralogy, 2008, s. 85-90Konferansepaper (Fagfellevurdert)
  • 72.
    Carlsson, Johannes
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Digital ljudkvalitetsoptimering för hörlurar.2011Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Detta examensarbete har utförts hos Dirac Research AB i Uppsala. Dirac Research är en världsledande programvaruspecialist inom ljudoptimering, rumskorrigering och ljudfältssyntes.

    Dirac har nu velat utreda hur man på bästa sätt kan använda deras programvara Dirac Live för att förbättra ljudet hos hörlurar. I examensarbetet ingick en teoretisk del om örat, hörlurar, mätmetoder och hur en frekvenskurva bör se ut. Det ingick också att mäta impulssvaret för några olika hörlurar. Impulssvaret användes sedan till att förbättra ljudet hos hörlurarna genom att designa digitala filter som användes genom programvaran Dirac Live. När filterdesignen var klar utfördes ett lyssningstest för att få åsikter om hur andra upplevde filtrena.

    Mätningarna utfördes på Karolinska Institutet i Huddingen på ett KEMAR-huvud. Det är ett konsthuvud som ska efterlikna en människas huvud till form och storlek. Där mättes fyra earbuds (intra-concha), tre in-ear (insert), två omslutande (circum-aural) och ett par utanpåliggande (supra-aural) hörlurar upp. Med filterdesignen visade det sig att förbättringar upplevdes på de flesta av hörlurarna. Dock så kompenserades inte de omslutande- och utanpåliggande hörlurarna något. Dessa var endast tänkta att ha som referens.

    Det var en del skillnader mellan de olika hörlurarnas frekvenssvar. Det beror delvis på hörselgångens resonansfrekvens. När omslutande hörlurar mäts kan hörselgången ses som en kvartsvågsresonator medan den vid mätning av in-ear-hörlurar kan ses som halvvågsresonator. Även hörlurarnas konstruktion påverkar skillnaderna för de olika hörlurstyperna.

    Som målkurvor till hörlurarna användes bland annat högtalarmätningar i form av frifältsmätningar och diffusfältsmätningar utöver de hörlurar som användes som referens. Dock upplevdes en frekvensgång med en mjuk topp vid 3 kHz och i övrigt ganska rak frekvensgång som bäst. Vid lyssningstestet var det även den kurvan som fick flest röster hos tre av de fyra hörlurarna som användes vid lyssningstestet.

  • 73.
    Carrascosa, Carlos
    et al.
    Universitat Politécnica de Valencia, Valencia, Spain.
    Klügl, Franziska
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Ricci, Alessandro
    Universita di Bologna, Cesena, Italy.
    Virtual Environments 4 MAS2014Inngår i: E4MAS - 10 Years Later. Workshop at AAMAS 2014 / [ed] D. Weyns et al., 2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The environment is a key point when talking about MASapplications, being a key concept when developing a platform or appli-cation in the past ten years: what is important in it and how to access it.At the same time, technology has evolved so that Virtual Environment-kinds of applications have grown out of science ction novels till researchpapers and even real applications. Current technology makes possible toMAS to interact also in this environments.In this paper, we have looked for the common ground that have all thedierent domains relating Virtual Environments as E4MAS, and we havecharacterized those domains according to three dimensions: connectionto the physical world of the environment, agents nature, and sociability.Moreover, we comment one of these domains, Mirror Worlds, as it is oneof the most complex domains commented, that we believe that is one ofthe topics to take into account in the near future both as a researh anddeveloping domain.

  • 74. Cesta, Amedeo
    et al.
    Cortellessa, Gabriella
    Rasconi, Riccardo
    Pecora, Federico
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Scopelliti, Massimiliano
    Tiberio, Lorenza
    Monitoring elderly people with the robocare domestic environment: interaction synthesis and user evaluation2011Inngår i: Computational intelligence, ISSN 0824-7935, E-ISSN 1467-8640, Vol. 27, nr 1, s. 60-82Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This article describes aspects of a fully implemented artificial intelligence (AI) system that integrates multiple intelligent components to actively assist an elderly person at home. Specifically, we describe how constraint-based scheduling technology is used to actively monitor a pattern of activities executed by the person and how detected temporal constraint violations are used to trigger meaningful and contextualized proactive interactions. This article also presents a psychological evaluation of the system focusing on elderly people’s attitudes, in which system acceptability, perceived utility, interaction modality, and emotional response are considered.

  • 75.
    Charusta, Krzysztof
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Dimitrov, Dimitar
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lilienthal, Achim J.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Iliev, Boyko
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Extraction of grasp-related features by human dual-hand object exploration2009Inngår i: 2009 International Conference on Advanced Robotics, Piscataway, NJ: IEEE conference proceedings, 2009, s. 1-6Konferansepaper (Fagfellevurdert)
    Abstract [en]

    We consider the problem of objects exploration for grasping purposes, specifically in cases where vision based methods are not applicable. A novel dual-hand object exploration method is proposed that takes benefits from a human demonstration to enrich knowledge about an object. The user handles an object freely using both hands, without restricting the object pose. A set of grasp-related features obtained during exploration is demonstrated and utilized to generate grasp oriented bounding boxes that are basis for pre-grasp hypothesis. We believe that such exploration done in a natural and user friendly way creates important link between an operator intention and a robot action.

  • 76.
    Cielniak, Grzegorz
    et al.
    Sch Comp Sci, Lincoln Univ, Lincoln, England.
    Duckett, Tom
    Sch Comp Sci, Lincoln Univ, Lincoln, England.
    Lilienthal, Achim J.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Data association and occlusion handling for vision-based people tracking by mobile robots2010Inngår i: Robotics and Autonomous Systems, ISSN 0921-8890, E-ISSN 1872-793X, Vol. 58, nr 5, s. 435-443Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents an approach for tracking multiple persons on a mobile robot with a combination of colour and thermal vision sensors, using several new techniques. First, an adaptive colour model is incorporated into the measurement model of the tracker. Second, a new approach for detecting occlusions is introduced, using a machine learning classifier for pairwise comparison of persons (classifying which one is in front of the other). Third, explicit occlusion handling is incorporated into the tracker. The paper presents a comprehensive, quantitative evaluation of the whole system and its different components using several real world data sets. (C) 2010 Elsevier B.V. All rights reserved.

  • 77.
    Cirillo, Marcello
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Planning in Inhabited Environments: Human-Aware Task Planning and Activity Recognition2010Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    Promised some decades ago by researchers in artificial intelligence and robotics as an imminent breakthrough in our everyday lives, a robotic assistant that could work with us in our home and our workplace is a dream still far from being fulfilled. The work presented in this thesis aims at bringing this future vision a little closer to realization. Here, we start from the assumption that an efficient robotic helper should not impose constraints on users' activities, but rather perform its tasks unobtrusively to fulfill its goals and to facilitate people in achieving their objectives.  Also, the helper should be able to consider the outcome of possible future actions by the human users, to assess how those would affect the environment with respect to the agent's objectives, and to predict when its support will be needed. In this thesis we address two highly interconnected problems that are essential for the cohabitation of people and service robots: robot task planning and human activity recognition. First, we present human-aware planning, that is, our approach to robot high-level symbolic reasoning for plan generation. Human-aware planning can be applied in situations where there is a controllable agent, the robot, whose actions we can plan, and one or more uncontrollable agents, the human users, whose future actions we can only try to predict. In our approach, therefore, the knowledge of the users' current and future activities is an important prerequisite. We define human-aware as a new type of planning problem, we formalize the extensions needed by a classical planner to solve such a problem, and we present the implementation of a planner that satisfies all identified requirements. In this thesis we explore also a second issue, which is a prerequisite to the first one: human activity monitoring in intelligent environments. We adopt a knowledge driven approach to activity recognition, whereby a constraint-based domain description is used to correlate sensor readings to human activities. We validate our solutions to both human-aware planning and activity recognition both theoretically and experimentally, describing a number of explanatory examples and test runs in a real environment.

  • 78.
    Cirillo, Marcello
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Karlsson, Lars
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    A framework for human-aware robot planning2008Inngår i: Tenth Scandinavian conference on artificial intelligence / [ed] A. Holst, P. Kreuger, P. Funk, Amsterdam: IOS press , 2008, s. 52-59Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Robots that share their workspace with humans, like household or service robots, need to take into account the presence of humans when planning their actions. In this paper, we present a framework for human-aware planning in which we consider three kinds of human-robot interaction. We focus in particular on the core module of the framework, a human-aware planner that generates a sequence of actions for a robot, taking into account the status of the environment, the goals of the robot and the forecasted plan of the human. We present a first realization of this planner, together with two simple experiments that demonstrate the feasibility of our approach.

  • 79.
    Cirillo, Marcello
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Karlsson, Lars
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    A human-aware robot task planner2009Inngår i: Proceedings of the 19th international conference on automated planning and scheduling, ICAPS 2009 / [ed] Alfonso Gerevini, Adele Howe, Amedeo Cesta, Ioannis Refanidis, Menlo Park: AAAI press , 2009, s. 58-65Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The growing presence of household robots in inhabited environments arises the need for new robot task planning techniques. These techniques should take into consideration not only the actions that the robot can perform or unexpected external events, but also the actions performed by a human sharing the same environment, in order to improve the cohabitation of the two agents, e.g., by avoiding undesired situations for the human. In this paper, we present a human-aware planner able to address this problem. This planner supports alternative hypotheses of the human plan, temporal duration for the actions of both the robot and the human, constraints on the interaction between robot and human, partial goal achievement and, most importantly, the possibility to use observations of human actions in the policy generated for the robot. The planner has been tested as a standalone component and in conjunction with our framework for human-robot interaction in a real environment.

  • 80.
    Cirillo, Marcello
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Karlsson, Lars
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Human-aware task planning: an application to mobile robots2010Inngår i: ACM transactions on interactive intelligent systems, ISSN 2157-6904, Vol. 1, nr 2, s. Article 15-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Consider a house cleaning robot planning its activities for the day. Assume that the robot expects the human inhabitant to first dress, then have breakfast, and finally go out. Then, it should plan not to clean the bedroom while the human is dressing, and to clean the kitchen after the human has had breakfast. In general, robots operating in inhabited environments, like households and future factory floors, should plan their behavior taking into account the actions that will be performed by the humans sharing the same environment. This would improve human-robot cohabitation, for example, by avoiding undesired situations for the human. Unfortunately, current task planners only consider the robot's actions and unexpected external events in the planning process, and cannot accommodate expectations about the actions of the humans.

    In this article, we present a human-aware planner able to address this problem. Our planner supports alternative hypotheses of the human plan, temporal duration for the actions of both the robot and the human, constraints on the interaction between robot and human, partial goal achievement and, most importantly, the possibility to use observations of human actions in the policy generated for the robot. Our planner has been tested both as a stand-alone component and within a full framework for human-robot interaction in a real environment.

  • 81.
    Cirillo, Marcello
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Karlsson, Lars
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Human-aware task planning for mobile robots2009Inngår i: Proceedings of the 5th international conference on advanced robotics, ICAR 2009, New York: IEEE conference proceedings, 2009, s. 172-178Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Robots that share their workspace with people, like household or service robots, need to take into account the presence of humans when planning their actions. In this paper, we present a framework for human-aware planning that would make the robots capable of performing their tasks without interfering with the user in his every day life. We focus in particular on the core module of the framework, a humanaware planner that generates a sequence of actions for a robot, taking into account the state of the environment and the goals of the robot, together with a set of forecasted possible plans of the human. We describe the planner and its relations to other system components like a plan recognizer, and present a series of experiments performed with a household robot in a small apartment.

  • 82.
    Cirillo, Marcello
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lanzellotto, Federica
    Roma 3 University, Rome, Italy.
    Pecora, Federico
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Monitoring domestic activities with temporal constraints and components2009Inngår i: Intelligent environments 2009 / [ed] V. Callaghan, A. Kameas, A. Reyes, D. Royo, M. Weber, Amsterdam: IOS Press, 2009, s. 117-124Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Intelligent environments are increasingly rich in ubiquitous sensing capabilities that can be leveraged to know which actions a user is engaged in at any given moment in time. The ability of an intelligent environment to recognize a high-level plan of activities performed by the user in a smart home would allow to construct proactive services, such as reminding, forecasting and providing timely physical support. This article proposes an approach to human activity recognition based on temporal planning. The approach leverages on one hand the ubiquitous sensors provided by the PEIS-Home, a sensor-rich intelligent environment, and, on the other hand, the temporal representation and reasoning capabilities of OMPS, a constraint-based temporal planning and scheduling framework.

  • 83.
    Cirillo, Marcello
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Pecora, Federico
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Proactive assistance in ecologies of physically embedded intelligent systems: a constraint-based approach2011Inngår i: Handbook of research on ambient intelligence and smart environments: trends and perspectives / [ed] Nak-Young Chong, Fulvio Mastrogiovanni, IGI Global, 2011, s. 534-557Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    The main goal of this Chapter is to introduce SAM, an integrated architecture for concurrent activity recognition, planning and execution. SAM provides a general framework to define how an intelligent environment can assess contextual information from sensory data. The architecture builds upon a temporal reasoning framework operating in closed-loop between physical sensing and actuation components in a smart environments. The capabilities of the system as well as possible examples of its use are discussed in the context of the PEIS-Home, a smart environment integrated with robotic components.

  • 84.
    Comstedt, Daniel
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Boström, Björn
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Ekblad, Alf
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Autotrophic and heterotrophic soil respiration in a Norway spruce forest: estimating the root decomposition and soil moisture effects in a trenching experiment2011Inngår i: Biogeochemistry, ISSN 0168-2563, E-ISSN 1573-515X, Vol. 104, nr 1-3, s. 121-132Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The two components of soil respiration, autotrophic respiration (from roots, mycorrhizal hyphae and associated microbes) and heterotrophic respiration (from decomposers), was separated in a root trenching experiment in a Norway spruce forest. In June 2003, cylinders (29.7 cm diameter) were inserted to 50 cm soil depth and respiration was measured both outside (control) and inside the trenched areas. The potential problems associated with the trenching treatment, increased decomposition of roots and ectomycorrhizal mycelia and changed soil moisture conditions, were handled by empirical modelling. The model was calibrated with respiration, moisture and temperature data of 2004 from the trenched plots as a training set. We estimate that over the first 5 months after the trenching, 45% of respiration from the trenched plots was an artefact of the treatment. Of this, 29% was a water difference effect and 16% resulted from root and mycelia decomposition. Autotrophic and heterotrophic respiration contributed to about 50% each of total soil respiration in the control plots averaged over the two growing seasons. We show that the potential problems with the trenching, decomposing roots and mycelia and soil moisture effects, can be handled by a modelling approach, which is an alternative to the sequential root harvesting technique.

  • 85.
    Coradeschi, Silvia
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Akademin för naturvetenskap och teknik.
    A review of Past and Future Trends in Perceptual Anchoring2008Inngår i: Tools in Artificial Intelligence, Vienna: I-Tech Eduacation and Publishing , 2008Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 86.
    Coradeschi, Silvia
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Kristoffersson, Annica
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Cortellessa, Gabriella
    Consiglio Nazionale delle Ricerche (CNR), Rome, Italy; Istituto di Scienze e Tecnologie della Cognizione (ISTC-CNR), Rome, Italy.
    Severinson Eklundh, Kerstin
    KTH, Royal Institute of Technology, Stockholm, Sweden.
    Social robotic telepresence2011Inngår i: the 6th ACM/IEEE International Conference on Human-Robot Interaction (HRI 2011).HRI, ACM Digital Library , 2011, s. 5-6Konferansepaper (Fagfellevurdert)
  • 87. Cortellessa, Gabriella
    et al.
    Loutfi, Amy
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Pecora, Federico
    Örebro universitet, Akademin för naturvetenskap och teknik.
    An on-going evaluation of domestic robots2008Inngår i: Robotic helpers: user interaction, interfaces and companions in assistive and therapy robotics, 2008, s. 87-91Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this position paper we describe an on-going effort to provide an in-depth and cross-cultural evaluation of how elderly users perceive robotic systems for domestic cognitive support. Our work is grounded on two implemented smarthome prototypes, namely the RoboCare Smart Home developed in Italy, and the PEIS Home developed in Sweden. The former project has provided a testbed for an a-posteriori evaluation of smart home technology with Italian user groups. The presence in Sweden of the PEIS Home, a system which shares numerous commonalities with the RoboCare Smart Home, gives us the opportunity to extend these results by (1) providing a cross-cultural perspective on the perception of smart home technology, and (2) lay the foundations for a live, Wizard of Oz based evaluation within the PEIS Home.

     

  • 88. Cortellessa, Gabriella
    et al.
    Scopelliti, Massimiliano
    Tiberio, Lorenza
    Koch Svedberg, Gion
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Pecora, Federico
    Örebro universitet, Akademin för naturvetenskap och teknik.
    A cross-cultural evaluation of domestic assistive robots2008Inngår i: AAAI fall symposium: technical report, v FS-08-02, American Association for Artificial Intelligence , 2008, s. 24-31Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents the first steps in a series of on-going user evaluations of intelligent environments for supporting elderly users at home. We specifically focus on a comparison of elderly perceptions of social assistive domestic robots between Italian and Swedish user groups. The evaluation was carried out in Rome, Italy and O¨ rebro, Sweden, including surrounding towns. The results, obtained through a videobased methodology, highlight the variety in level of appreciation of domestic robots for elderly care as it relates to a number of aspects of culture which are not necessarily trivial to identify. Our results suggest some specific factors as important for interpreting the difference in perception, e.g., the user’s acquaintance with ICT (Information and Communication Technology) and the social policies implemented in the two countries. Also, the results show interesting commonalities, such as the general agreement among Swedish and Italian user groups on the physical aspect of the robot.

  • 89.
    Dahlbom, Anders
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Petri nets for situation recognition2011Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    Situation recognition is a process with the goal of identifying a priori defined situations in a flow of data and information. The purpose is to aid decision makers with focusing on relevant information by filtering out situations of interest. This is an increasingly important and non trivial problem to solve since the amount of information in various decision making situations constantly grow. Situation recognition thus addresses the information gap, i.e. the problem of finding the correct information at the correct time. Interesting situations may also evolve over time and they may consist of multiple participating objects and their actions. This makes the problem even more complex to solve. This thesis explores situation recognition and provides a conceptualization and a definition of the problem, which allow for situations of partial temporal definition to be described. The thesis then focuses on investigating how Petri nets can be used for recognising situations. Existing Petri net based approaches for recognition have some limitations when it comes to fulfilling requirements that can be put on solutions to the situation recognition problem. An extended Petri net based technique that addresses these limitations is therefore introduced. It is shown that this technique can be as efficient as a rule based techniques using the Rete algorithm with extensions for explicitly representing temporal constraints. Such techniques are known to be efficient; hence, the Petri net based technique is efficient too. The thesis also looks at the problem of learning Petri net situation templates using genetic algorithms. Results points towards complex dynamic genome representations as being more suited for learning complex concepts, since these allow for promising solutions to be found more quickly compared with classical bit string based representations. In conclusion, the extended Petri net based technique is argued to offer a viable approach for situation recognition since it: (1) can achieve good recognition performance, (2) is efficient with respect to time, (3) allows for manually constructed situation templates to be improved and (4) can be used with real world data to find real world situations.

  • 90. Dahlbom, Anders
    et al.
    Niklasson, Lars
    Falkman, Göran
    Loutfi, Amy
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Towards template-based situation recognition2009Inngår i:  Intelligent sensing, situation management, impact assessment, and cyber-sensing / [ed] Stephen Mott, John F. Buford, Gabriel Jakobson, Michael J. Mendenhall, 2009, Vol. 7352, nr 1, s. 7352 05-Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    The process of tracking and identifying developing situations is an ability of importance within the surveillance domain. We refer to this as situation recognition and believe that it can enhance situation awareness for decision makers. Situation recognition requires that many subproblems are solved. For instance, we need to establish which situations are interesting, how to represent these situations, and which inferable events and states that can be used for representing them. We also need to know how to track and identify situations and how to determine the correlation between present information about situations with knowledge. For some of these subproblems, data-driven approaches are suitable, whilst knowledge-driven approaches are more suitable for others. In this paper we discuss our current research efforts and goals concerning template-based situation recognition. We provide a categorization of approaches for situation recognition together with a formalization of the template-based situation re ognition problem. We also discuss this formalization in the light of a pick-pocket scenario. Finally, we discuss future directions for our research on situation recognition. We conclude that situation recognition is an important problem to look into for enhancing the overall situation awareness of decision makers. ©2009 SPIE.

  • 91.
    Daoutis, Marios
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Coradeschi, Silvia
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Grounding commonsense knowledge in intelligent systems2009Inngår i: Journal of Ambient Intelligence and Smart Environments, ISSN 1876-1364, E-ISSN 1876-1372, Vol. 1, nr 4, s. 311-321Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ambient environments which integrate a number of sensing devices and actuators intended for use by human users need to be able to express knowledge about objects, their functions and their properties to assist in the performance of everyday tasks. For this to occur perceptual data must be grounded to symbolic information that in its turn can be used in the communication with the human. For symbolic information to be meaningful it should be part of a rich knowledge base that includes an ontology of concepts and common sense. In this work we present an integration between ResearchCyc and an anchoring framework that mediates the connection between the perceptual information in an intelligent home environment and the reasoning system. Through simple dialogues we validate how objects placed in the home environment are grounded by a network of sensors and made available to a larger KB where reasoning is exploited. This first integration work is a step towards integrating the richness of a KRR system developed over many years in isolation, with a physically embedded intelligent system.

  • 92.
    Daoutis, Marios
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Coradeschi, Silvia
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Integrating common sense in physically embedded intelligent systems2009Inngår i: Intelligent environments 2009 / [ed] V. Callaghan, A. Kameas, A. Reyes, D. Royo, M. Weber, Amsterdam: IOS Press , 2009, s. 212-219Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper we describe an implemented framework that integrates knowledge representation and reasoning in a symbiotic system. In such systems a number of heterogeneous sensors pervasively embedded in the environment, mobile robots and humans co-exist and communicate. In this work, the integration is mediated through perceptual anchoring, which creates and maintains the correspondences between the symbol system and the perceptual data that refer to the same physical object. The overall framework is evaluated using ResearchCyc as the knowledge representation and reasoning system, within the context of a physical testbed, which consists of a small apartment-like home.

  • 93.
    Davidsson, Kenth
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Förbättringsförslag för en robotcell:  2011Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Detta examensarbete består i en översyn av en robotcell för programmering av målningsrobotar hos Meritor HVS AB i Lindesberg. Företaget är verksamt inom fordonsindustrin med tillverkning av fram- och bakaxlar för tunga fordon.

    Förslag till åtgärder för minskat antal stopp i måleriet och förbättrad målningskvalitet i anläggningen presenteras, liksom förbättringsförslag för programmeringscellens layout och programmeringsverksamhetens organisation.

  • 94. de Boer, J.
    et al.
    Leslie, H.
    van Leeuwen, S. P. J.
    Wegener, J.-W.
    van Bavel, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lindström, Gunilla
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lahoutifard, N.
    Fiedler, Heidelore
    UNEP Chemicals, CH-1219 Châtelaine (GE), Switzerland.
    United Nations Environment Programme Capacity Building Pilot Project: training and interlaboratory study on persistent organic pollutant analysis under the Stockholm Convention2008Inngår i: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 617, nr 1-2, s. 208-215Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Within the framework of a United Nations Environment Programme (UNEP) Capacity Building Project for training of laboratory staff in developing countries on persistent organic pollutant (POP) analysis, an interlaboratory study was organised following an initial evaluation of the performance of laboratories (reality check) and a series of training sessions. The target compounds were polychlorinated biphenyls (PCB) and organochlorine pesticides (OCP). Seven laboratories from five countries (Ecuador, Uruguay, Kenya, Moldova, and Fiji) participated. Most of the laboratories had no experience in determining PCBs. Although chromatograms improved considerably after the training and installation of new gas chromatographic (GC) columns at participating laboratories, the level of performance in the interlaboratory study was essentially on par with the moderate performance level achieved by European POP laboratories in the 1980s. Only some individual results were within +/-20% of the target values. The relative standard deviations (R.S.D.s) in POP concentrations determined by laboratories in a sediment sample were >200% in a number of cases. The results for a certified herring sample were better with at least some R.S.D. values below 50% and most below 100%. Clean up was as one of the main sources of error. After inspection it was ascertained that training of laboratory staff and investments in simple consumables such as glassware and GC columns would help to improve the quality of the analysis more than major investments in expensive instrumentation. Creating an effective network of POP laboratories at different continents together with a series of interlaboratory studies and workshops is suggested to improve the measurements of POPs in these countries.

  • 95. de Boer, Jacob
    et al.
    van Bavel, Bert
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Special Issue Tools for the Reach Programme - Analytical Methods for the Evaluation of Industrial Contaminants: Foreword2009Inngår i: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1216, nr 3, s. 301-301Artikkel i tidsskrift (Fagfellevurdert)
  • 96.
    Di Lello, Enrico
    et al.
    Dept. of Informatics and Automation, University Roma-3, Italy.
    Loutfi, Amy
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Pecora, Federico
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Robotic furniture in a smart environment: the PEIS table2009Inngår i: Workshops Proceedings of the 5th International Conference on Intelligent Environments / [ed] Michael Schneider et al., Amsterdam: IOS Press, 2009, s. 185-192Konferansepaper (Fagfellevurdert)
    Abstract [en]

    According to a recent trend, robotic technologies will be included into domestic environments in the form of simple, networked robotic devices able to cooperate in the performance of tasks. These devices may take the form of smart appliances, distributed sensors, or robotic furniture. In this paper, we describe the design of an autonomous robotic table and its inclusion in a smart environment, the PEIS Ecology. The design takes into account the constraints posed by the domestic environment. The robotic table can perform autonomous point-to-point navigation, and it can collaborate with the other devices in the ecology to perform complex tasks that go beyond simple navigation.

  • 97. Di Lello, Enrico
    et al.
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    The PEIS table: an autonomous robotic table for domestic environments2011Inngår i: Automatika: Journal for Control, Measurement, Electronics, Computing and Communications, ISSN 0005-1144, E-ISSN 1848-3380, Vol. 52, nr 3, s. 244-255Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    There are two main trends in the area of home and service robotics. The classical one aims at the developmentof a single skilled servant robot, able to perform complex tasks in a passive environment. The second, more recenttrend aims at the achievement of complex tasks through the cooperation of a network of simpler robotic devicespervasively embedded in the domestic environment. This paper contributes to the latter trend by describing the PEISTable, an autonomous robotic table that can be embedded in a smart environment. The robotic table can operatealone, performing simple point-to-point navigation, or it can collaborate with other devices in the environment toperform more complex tasks. Collaboration follows the PEIS Ecology model. The hardware and software designof the PEIS Table are guided by a set of requirements for robotic domestic furniture that differ, to some extent, fromthe requirements usually considered for service robots.

  • 98.
    Di Lello, Enrico
    et al.
    Dept of Informatics and Automation, University Roma-3, Italy.
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    The PEIS table: an autonomous robotic table for domestic environments2009Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Two main trends are emerging in the area of home and service robotics. The classical one aims at the development of a single skilled servant robot, able to perform complex tasks in a passive environment. The second, more recent trend aims at the achievement of domestic tasks through the cooperation of a network of simpler robotic devices pervasively embedded in the environment. This paper contributes to the latter trend by describing the PEIS Table, a robotic table that can be embedded in a domestic environment and perform autonomous navigation tasks. The PEIS Table can operate alone, or it can be part of a smart robotic environment, based on the concept of PEIS Ecology, and cooperate with other devices to perform more complex tasks. The hardware construction and navigation software of the PEIS Table are guided by a set of requirements for robotic domestic furniture. Interestingly, these are not the same as the requirements usually considered for service robots.

  • 99.
    Di Rocco, Maurizio
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Reggente, Matteo
    Saffiotti, Alessandro
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Gas source localization in indoor environments using multiple inexpensive robots and stigmergy2011Inngår i: 2011 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), IEEE, 2011, s. 5007-5014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Environmental monitoring is a rather new field in robotics. One of the main appealing tasks is gas mapping, i.e., the characterization of the chemical properties (concentration, dispersion, etc.) of the air within an environment. Current approaches rely on a robot using standard localization and mapping techniques to fuse gas measures with spatial features. These approaches require sophisticated sensors and/or high computational resources. We propose a minimalistic approach, in which one or multiple low-cost robots exploit the ability to store information in the environment, or “stigmergy”, to effectively compute an artificial potential leading toward the likely location of the gas source, as indicated by a highest gas concentration or fluctuation. The potential is computed and stored directly on an array of RFID tags buried under the floor. Our approach has been validated in extensive experiments performed on real robots in a domestic environment.

  • 100.
    Dimitrov, Dimitar N.
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Wieber, P. -B.
    Stasse, O.
    Ferreau, H. J.
    Diedam, H.
    An optimized linear model predictive control solver for online walking motion generation2009Inngår i: IEEE International Conference on Robotics and Automation (ICRA '09), IEEE conference proceedings, 2009, s. 1171-1176Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    This article addresses the fast solution of a Quadratic Program underlying a Linear Model Predictive Control scheme that generates walking motions. We introduce an algorithm which is tailored to the particular requirements of this problem, and therefore able to solve it efficiently. Different aspects of the algorithm are examined, its computational complexity is presented, and a numerical comparison with an existing state of the art solver is made. The approach presented here, extends to other general problems in a straightforward way. © 2009 IEEE.

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