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  • 251.
    Bordag, Ljudmila A.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Symmetry reductions and exact solutions for nonlinear diffusion equations2009In: International Journal of Modern Physics A, ISSN 0217-751X, E-ISSN 1793-656X, Vol. 24, no 8/9, p. 1713-1716Article in journal (Refereed)
    Abstract [en]

    The symmetry properties of nonlinear diffusion equations are studied using a Lie group analysis. Reductions and families of exact solutions are found for some of these equations.

    © 2009 World Scientific Publishing Company.

  • 252.
    Bordag, Ljudmila A.
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Chmakova, A. Y.
    Fakultät Mathematik, Naturwissenschaften und Informatik, Brandenburgische Technische Universität Cottbus, Cottbus, Germany.
    Explicit solutions for a nonlinear model of financial derivatives2007In: International Journal of Theoretical and Applied Finance, ISSN 0219-0249, Vol. 10, no 1, p. 1-21Article in journal (Refereed)
    Abstract [en]

    Families of explicit solutions are found to a nonlinear Black-Scholes equation which incorporates the feedback-effect of a large trader in case of market illiquidity. The typical solution of these families will have a payoff which approximates a strangle. These solutions were used to test numerical schemes for solving a nonlinear Black-Scholes equation. © World Scientific Publishing Company.

  • 253.
    Bordag, Ljudmila A.
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Frey, Rüdiger
    Leipzig University, Department of Mathematics.
    Pricing options in illiquid markets: symmetry reductions and exact solutions2008In: Nonlinear Models in Mathematical Finance: New Research Trends in Option Pricing / [ed] Matthias Ehrhardt, New York: Nova Science Publishers, Inc., 2008, p. 103-130Chapter in book (Other academic)
    Abstract [en]

    The present paper is concerned with nonlinear Black Scholes equations arising in certain option pricing models with a large trader and/or transaction costs. In the first part we give an overview of existing option pricing models with frictions. While the financial setup differs between models, it turns out that in many of these models derivative prices can be characterized by fully nonlinear versions of the standard parabolic Black-ScholesPDE. In the second part of the paper we study a typical nonlinear Black-Scholes equation using methods from Lie group analysis. The equation possesses a rich symmetry group. By introducing invariant variables,  invariant solutions can therefore be characterized in terms of solutions to ordinary differential equations. Finally we discuss properties and applications of these solutions.

  • 254.
    Bordag, Ljudmila A.
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Matveev, Sergey K.
    St. Petersburger State University.
    Berechnungen der Gleichgewichtslage der Welle unterpräzisierten geometrischen Voraussetzungen der Druckfluidströmung in LHS 7502009Report (Other academic)
  • 255.
    Bordag, Ljudmila A.
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Matveev, Sergey K.
    St. Petersburg State University.
    Erste  Berechnungen der Druckfluidströmung2008Report (Other academic)
  • 256.
    Bordag, Ljudmila A.
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Matveev, Sergey K.
    St. Petersburg State University.
    Präzisierte Berechnungender Druckfluidströmung in LHS 7502008Report (Other academic)
  • 257.
    Bordag, Ljudmila A.
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Mikaelyan, Anna
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Models of self-financing hedging strategies in illiquid markets: Symmetry reductions and exact solutions2011In: Letters in Mathematical Physics, ISSN 0377-9017, E-ISSN 1573-0530, Vol. 96, no 1-3, p. 191-207Article in journal (Refereed)
    Abstract [en]

    We study the general model of self-financing trading strategies inilliquid markets introduced by Schoenbucher and Wilmott, 2000.A hedging strategy in the framework of this model satisfies anonlinear partial differential equation (PDE) which contains somefunction g(alpha). This function is deep connected to anutility function.

    We describe the Lie symmetry algebra of this PDE and provide acomplete set of reductions of the PDE to ordinary differentialequations (ODEs). In addition we are able to describe all types offunctions g(alpha) for which the PDE admits an extended Liegroup. Two of three special type functions lead to modelsintroduced before by different authors, one is new. We clarify theconnection between these three special models and the generalmodel for trading strategies in illiquid markets. We study withthe Lie group analysis the new special case of the PDE describingthe self-financing strategies. In both, the general model and thenew special model, we provide the optimal systems of subalgebrasand study the complete set of reductions of the PDEs to differentODEs. In all cases we are able to provide explicit solutions tothe new special model. In one of the cases the solutions describepower derivative products.

  • 258.
    Bordag, Michael
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Interaction of a charge with a thin plasma sheet2007In: Physical Review D. Particles and fields, ISSN 0556-2821, E-ISSN 1089-4918, Vol. 76, no 6, p. 065011-Article in journal (Refereed)
    Abstract [en]

    The interaction of the electromagnetic field with a two-dimensional plasma sheet intended to describe the pi-electrons of a carbon nanotube or a C-60 molecule is investigated. By first integrating out the displacement field of the plasma or the electromagnetic field, different representations for quantities like the Casimir energy are derived which are shown to be consistent with one another. Starting from the covariant gauge for the electromagnetic field, it is shown that the matching conditions to which the presence of the plasma sheet can be reduced are different from the commonly used ones. The difference in the treatments does not show up in the Casimir force between two parallel sheets, but it is present in the Casimir-Polder force between a charge or a neutral atom and a sheet. At once, since the plasma sheet is a regularization of the conductor boundary conditions, this sheds light on the difference in physics found earlier in the realization of conductor boundary conditions as "thin" or "thick" boundary conditions in Phys. Rev. D 70, 085010 (2004).

  • 259.
    Bordag, Michael
    et al.
    Leipzig University, Institute for Theoretical Physics, Leipzig, Germany.
    Jede, Ralf
    Raith GmbH, Dortmund, Germany.
    Montelius, Lars
    Lunds University, Physics Department, Lund, Sweden.
    Pettersson, Håkan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Riu, Jordi
    University Rovira i Vergili, Taragona, Spain.
    Schmucker, Ulrich
    University Rovira i Vergili, Taragona, Spain.
    Zubtsov, Michael
    Fraunhofer Institute for Factory Automation, Magdeburg, Germany.
    Parallel nano-assembly directed by short-range field forces2006In: Proceedings of the 1st IEEE International Conference on Nano/Micro Engineered and Molecular Systems, Piscataway, United States: IEEE Press, 2006, p. 620-622, article id 4135031Conference paper (Refereed)
    Abstract [en]

    We present the ECs Sixth Framework Programme PARNASS project, which stands for 'Parallel nano assembling directed by short-range field forces' and represents a radical innovative approach to fabricating large volumes of hybrid nano electronic devices. The project combines in a synergy the 'top-down' and 'bottom-up' methods addressing one of the challenging physical and engineering problems of the very high accuracy over a large area. An array of specially designed nano-scale force field sources has to be a key part of this innovative approach to large-scale nano manufacturing. © 2006 IEEE.

  • 260.
    Bordag, Michael
    et al.
    Univ Leipzig, Vor Hospitaltore 1, D-04103 Leipzig, Germany..
    Nikolaev, Vladimir
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Analytic corrections to the electromagnetic casimir interaction between a sphere and a plate at shortdistances2010In: International Journal of Modern Physics A, ISSN 0217-751X, E-ISSN 1793-656X, Vol. 25, no 11, p. 2171-2176Article in journal (Refereed)
    Abstract [en]

    For the vacuum interaction of a sphere in front of a plane, both obeying conductor boundary conditions, we consider the approximation of small separation. We derive the next-to-leading order of the asymptotic expansion in the separation-to-radius ratio epsilon. This correction is of order epsilon. In opposite to the scalar cases it contains also contributions proportional to logarithms in first and second order, epsilon In epsilon and e(ln epsilon)(2). We compare this result with the available findings of numerical and experimental approaches.

  • 261.
    Bordag, Michael
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Applied Mathematics and Physics (CAMP).
    Ribayrol, Aline
    Lund University.
    Conache, Gabriela
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Applied Mathematics and Physics (CAMP).
    Fröberg, Linus E.
    Lund University.
    Gray, Struan
    Lund University.
    Samuelson, Lars
    Lund University.
    Montelius, Lars
    Lund University.
    Pettersson, Håkan
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Applied Mathematics and Physics (CAMP).
    Shear stress measurements on InAs nanowires by AFM manipulation2007In: Small, ISSN 1613-6810, Vol. 3, no 8, p. 1398-1401Article in journal (Refereed)
    Abstract [en]

    On an upward curve? The curvature of an elastically deformed nanowire pinned to a flat surface contains information about the maximum static friction force, and hence the shear stress, between the nanowire and the surface. Here, InAs nanowires are bent in a controlled manner using the tip of an atomic force microscope (see image). The shear stress can be obtained from a simple analysis according to the standard theory of elasticity.

  • 262.
    Borg, Johan
    et al.
    Halmstad University, School of Information Technology.
    From, Josefine
    Halmstad University, School of Information Technology.
    Cloud och konsulten: En studie om konsultens roll vid arbetet med cloudbaserade affärssystem2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Cloud computing beskrivs som ett paradigmskifte inom IT-branschen, cloudbaserade

    tjänster är här för att stanna. En del av cloudcomputing är cloudbaserade affärssystem.

    Genom att få både systemet och datalagringen tillhandahållen från en externsystemleverantör kan verksamheter lägga fullt fokus på sin kärnverksamhet

    och låtasystemleverantören sköta tekniken. Systemet kan dock behöva  anpassas

    för att passa verksamheten och integrering mellan ändra system kan krävas.

    Därför väljer många kunder att använda sig utav konsulter för att anpassa

    systemet och för att få hjälp att använda det på bästa satt.

    .

  • 263.
    Borg, Richard
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Svensson, Timmy
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Assistansrobot "Slangaren"2011Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project is a step towards automatic firefighting. The goal is to decrease the number of personal injuries by replacing the human firefighter with robots or similar technical tools. Especially in very hostile environments due to risk of explosions or building collapse. A robot is easy to replace and can be maneuvered from a safe distance. The idea of the project comes from the company Drones Networking which aims for developing a totally autonomous firefighting system. The result of this project is a prototype of a robot which handles the hose during firefighting.

  • 264.
    Borkowski, Kazimierz M.
    et al.
    Toruń Radio Astronomy Observatory, Nicolaus Copernicus University, Toruń, Poland.
    Bååth, L.B.
    Onsala Space Observatory, Chalmers University of Technology, Gothenburg, Sweden.
    Determination of the Toruń Antenna Position from VLBI Observations1992In: Acta Astronomica, ISSN 0001-5237, Vol. 42, p. 371-375Article in journal (Refereed)
    Abstract [en]

    Four strong radio sources were observed over a 12-hr session in March, 1990 between radio telescopes at Onsala and Torun at wavelength of 6 cm in the standard VLBI Mark II setup for the purpose of improving the coordinates of the Torun 15-meter antenna. The Cartesian coordinates of the antenna derived from the presented measurements are (in meters): 3638609.62 +/- 0.19, 1221773.23 +/- 0.54 and 5077024.50 +/- 1.66 in the x, y, and z directions, respectively.

  • 265.
    Borschel, Christian
    et al.
    Institute for Solid State Physics, Jena University, Max-Wien-Platz 1, 07743 Jena, Germany.
    Messing, Maria
    Avd. f. Fasta tillståndets fysik, Lunds Universitet.
    Borgström, Magnus T.
    Avd. f. Fasta tillståndets fysik, Lunds Universitet.
    Paschoal, Waldomiro
    Avd. f. Fasta tillståndets fysik, Lunds Universitet / Tillämpad matematik och fysik (MPE-lab), MPE-lab.
    Wallentin, Jesper
    Avd. f. Fasta tillståndets fysik, Lunds Universitet.
    Kumar, Sandeep
    Avd. f. Fasta tillståndets fysik, Lunds Universitet.
    Mergenthaler, Kilian
    Avd. f. Fasta tillståndets fysik, Lunds Universitet.
    Deppert, Knut
    Avd. f. Fasta tillståndets fysik, Lunds Universitet.
    Canali, C. M.
    Högskolan i Kalmar.
    Pettersson, Håkan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Samuelson, Lars
    Avd. f. Fasta tillståndets fysik, Lunds Universitet.
    Ronning, Carsten
    Institute for Solid State Physics, Jena University, Max-Wien-Platz 1, 07743 Jena, Germany.
    A New Route toward Semiconductor Nanospintronics: Highly Mn-Doped GaAs Nanowires Realized by Ion-Implantation under Dynamic Annealing Conditions2011In: Nano letters (Print), ISSN 1530-6984, E-ISSN 1530-6992, Vol. 11, no 9, p. 3935-3940Article in journal (Refereed)
    Abstract [en]

    We report on highly Mn-doped GaAs nanowires (NWs) of high crystalline quality fabricated by ion beam implantation, a technique that allows doping concentrations beyond the equilibrium solubility limit. We studied two approaches for the preparation of Mn-doped GaAs NWs: First, ion implantation at room temperature with subsequent annealing resulted in polycrystalline NWs and phase segregation of MnAs and GaAs. The second approach was ion implantation at elevated temperatures. In this case, the single-crystallinity of the GaAs NWs was maintained, and crystalline, highly Mn-doped GaAs NWs were obtained. The electrical resistance of such NWs dropped with increasing temperature (activation energy about 70 meV). Corresponding magnetoresistance measurements showed a decrease at low temperatures, indicating paramagnetism. Our findings suggest possibilities for future applications where dense arrays of GaMnAs nanowires may be used as a new kind of magnetic material system.

  • 266.
    Borschel, Christian
    et al.
    Institute for Solid State Physics, University of Jena, Jena, Germany.
    Messing, Maria
    Lund University, Lund, Sweden.
    Mergenthaler, Kilian
    Lund University, Lund, Sweden.
    Borgström, Magnus T.
    Lund University, Lund, Sweden.
    Paschoal, Waldomiro
    Lund University, Lund, Sweden.
    Wallentin, Jesper
    Lund University, Lund, Sweden.
    Kumar, Sandeep
    Lund University, Lund, Sweden.
    Deppert, Knut
    Lund University, Lund, Sweden.
    Canali, Carlo
    Linnaeus University, Kalmar, Sweden.
    Pettersson, Håkan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Samuelson, Lars
    Lund University, Lund, Sweden.
    Ronning, Carsten
    Institute for Solid State Physics, University of Jena, Jena, Germany.
    A New Route towards Semiconductor Nanospintronics: Highly Mn-Doped GaAs Nanowires Realized by Ion-Implantation under Dynamic Annealing Conditions2011Conference paper (Refereed)
  • 267.
    Borssén, Theres
    Halmstad University, School of Business and Engineering (SET).
    Hur miljöinriktad är avfallshanteringen?: En studie om hur sex kommuner avser att uppnå miljömålen med sina avfallsplaner2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report presents a comparative study of municipal waste management plans. Six waste management plans from different municipalities in Sweden have been studied and compared. The comparison of waste management plans have been made according to how the municipal waste treatment works from an environmental perspective. The comparison of the waste management plans has been compiled in a table to make it easier to discern differences and similarities. The points that have been studied in the municipal waste management plans are;

    • Waste plan's objectives
    • Description of current situation - waste management and collection system (for houses and apartment buildings
    • How the waste management plan complies with the European Union’s approach to waste management.

    The factors listed above have been studied regarding to EU's waste hierarchy, rules and regulations regarding waste management and the current environmental goals. This is the basis for assessing how waste management works in a environmental perspective. How the municipalities achieve environmental goals and regulations regarding waste management have also been studied.

    The results shows that there are differences regarding collection systems and treatment methods within the different municipalities. Treatment methods of wastes is a contributing factor to achieve the environmental goal "A good urban environment".

    Biological treatment of food wastes is necessary to achieve the environmental goal "A good urban environment". Of the six municipalities who are studied, it shows that only three municipalities have collections of food wastes for their households. This means that only three of the municipalities achieve the environmental objectives regarding increased recycling of food wastes.

  • 268.
    Boti, Ismael
    Halmstad University, School of Business and Engineering (SET).
    Noise spectra comparison among wind turbinesand its implications to human perception.2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The noise coming from wind power development can be an environmental impact forthe surrounding communities. It is well known that the main wind turbine noise iscaused by the movement of the turbine wings through the air. However, there areuncertainties about the importance of machinery sounds and possible variations amongwind turbines. A high resolution acquisition system was used to perform a fieldexperiment comparison of the noise spectra from some wind turbines at Laholm(Sweden). The results have shown different band spectra peaks associated to machinerysounds among wind turbines from the same model and also from those of differentmanufactures. Maintenance conditions of these wind turbines could explain thedifferences in intensity and frequency locations of the band spectra peaks found. Inorder to know the importance for human audition of these peaks, listening test or doseresponsestudies would be needed to provide relevant information in this regard. Themethodology developed in this study is suggested to be useful for identifying certainmachinery failures which could corrupt the noise sounds emitted at certain wind turbinelocations.

  • 269.
    Bouguelia, Mohamed-Rafik
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Gonzalez, Ramon
    Robotic Mobility Group, Massachusetts Institute of Technology, Cambridge, USA.
    Iagnemma, Karl
    Robotic Mobility Group, Massachusetts Institute of Technology, Cambridge, USA.
    Byttner, Stefan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Unsupervised classification of slip events for planetary exploration rovers2017In: Journal of terramechanics, ISSN 0022-4898, E-ISSN 1879-1204, Vol. 73, p. 95-106Article in journal (Refereed)
    Abstract [en]

    This paper introduces an unsupervised method for the classification of discrete rovers' slip events based on proprioceptive signals. In particular, the method is able to automatically discover and track various degrees of slip (i.e. low slip, moderate slip, high slip). The proposed method is based on aggregating the data over time, since high level concepts, such as high and low slip, are concepts that are dependent on longer time perspectives. Different features and subsets of the data have been identified leading to a proper clustering, interpreting those clusters as initial models of the prospective concepts. Bayesian tracking has been used in order to continuously improve the parameters of these models, based on the new data. Two real datasets are used to validate the proposed approach in comparison to other known unsupervised and supervised machine learning methods. The first dataset is collected by a single-wheel testbed available at MIT. The second dataset was collected by means of a planetary exploration rover in real off-road conditions. Experiments prove that the proposed method is more accurate (up to 86% of accuracy vs. 80% for K-means) in discovering various levels of slip while being fully unsupervised (no need for hand-labeled data for training). © 2017 ISTVS

  • 270.
    Bouguelia, Mohamed-Rafik
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Karlsson, Alexander
    University of Skövde, Skövde, Sweden.
    Pashami, Sepideh
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Nowaczyk, Sławomir
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Holst, Anders
    Swedish Institute of Computer Science, Kista, Sweden.
    Mode tracking using multiple data streams2018In: Information Fusion, ISSN 1566-2535, E-ISSN 1872-6305, Vol. 43, p. 33-46Article in journal (Refereed)
    Abstract [en]

    Most existing work in information fusion focuses on combining information with well-defined meaning towards a concrete, pre-specified goal. In contradistinction, we instead aim for autonomous discovery of high-level knowledge from ubiquitous data streams. This paper introduces a method for recognition and tracking of hidden conceptual modes, which are essential to fully understand the operation of complex environments. We consider a scenario of analyzing usage of a fleet of city buses, where the objective is to automatically discover and track modes such as highway route, heavy traffic, or aggressive driver, based on available on-board signals. The method we propose is based on aggregating the data over time, since the high-level modes are only apparent in the longer perspective. We search through different features and subsets of the data, and identify those that lead to good clusterings, interpreting those clusters as initial, rough models of the prospective modes. We utilize Bayesian tracking in order to continuously improve the parameters of those models, based on the new data, while at the same time following how the modes evolve over time. Experiments with artificial data of varying degrees of complexity, as well as on real-world datasets, prove the effectiveness of the proposed method in accurately discovering the modes and in identifying which one best explains the current observations from multiple data streams. © 2017 Elsevier B.V. All rights reserved.

  • 271.
    Bouguelia, Mohamed-Rafik
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Nowaczyk, Sławomir
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Santosh, K. C.
    The University of South Dakota, Vermillion, South Dakota, USA.
    Verikas, Antanas
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Agreeing to disagree: active learning with noisy labels without crowdsourcing2018In: International Journal of Machine Learning and Cybernetics, ISSN 1868-8071, E-ISSN 1868-808X, Vol. 9, no 8, p. 1307-1319Article in journal (Refereed)
    Abstract [en]

    We propose a new active learning method for classification, which handles label noise without relying on multiple oracles (i.e., crowdsourcing). We propose a strategy that selects (for labeling) instances with a high influence on the learned model. An instance x is said to have a high influence on the model h, if training h on x (with label y = h(x)) would result in a model that greatly disagrees with h on labeling other instances. Then, we propose another strategy that selects (for labeling) instances that are highly influenced by changes in the learned model. An instance x is said to be highly influenced, if training h with a set of instances would result in a committee of models that agree on a common label for x but disagree with h(x). We compare the two strategies and we show, on different publicly available datasets, that selecting instances according to the first strategy while eliminating noisy labels according to the second strategy, greatly improves the accuracy compared to several benchmarking methods, even when a significant amount of instances are mislabeled. © Springer-Verlag Berlin Heidelberg 2017

  • 272.
    Bouguerra, Abdelbaki
    et al.
    Centre for Applied Autonomous Sensor Systems (AASS), Örebro University.
    Andreasson, Henrik
    Centre for Applied Autonomous Sensor Systems (AASS), Örebro University.
    Lilienthal, Achim J
    Centre for Applied Autonomous Sensor Systems (AASS), Örebro University.
    Åstrand, Björn
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Rögnvaldsson, Thorsteinn
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    MALTA: A System of Multiple Autonomous Trucks for Load Transportation2009In: Proceedings of the 4th European Conference on Mobile Robots: ECMR’09, September 23 – 25, 2009 Mlini/Dubrovnik, Croatia / [ed] Ivan Petrovi´c Achim J. Lilienthal, Zagreb: KoREMA , 2009, p. 91-96Conference paper (Refereed)
    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.

  • 273.
    Brandt, Sofie
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Hjälpmedel som underlättar öppnandet av skruvkorkar: - ett produktutvecklingsprojekt2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Every day we encounter various types of packaging. For many people, the opening of these packages is a difficult task, since it requires a certain degree of hand strength to succeed. Reduced hand strength can be a result of injuries or diseases such as Parkinson's disease, finger-joint osteoarthritis and rheumatoid arthritis. Aging also has a negative effect on hand strength and function. An example of packaging that is difficult to open, is the ones with a plastic screw cap. Many packages, containing juice and milk products, as well as PET bottles, have this design. Today there are many tools in order to open these packages, but tests of existing facilities indicate that they do not meet user demands for functionality and usability. Therefore, the aim of the project was to develop a functional product that fits so many cap sizes as possible, and also be designed so that it can access the cap on all packaging.

    As part of the product development process, a group of women, 67-85 years old, who all experience difficulties in opening packaging with screw caps, was interviewed. Their views and opinions were of great importance for the project. Furthermore, brainstorming, sketching, prototyping and CAD modeling were methods used in the project. The CAD model was used to manufacture the product.

    The project resulted in a functioning product made of aluminum, and fits all cap sizes with a diameter of 25-41 mm, which includes all caps in today's packaging for juice and milk products, as well as PET bottles. The product is using a lever, which reduces the power consumption by up to 92%, and will facilitate the opening of packaging with screw caps for people with reduced hand strength.

  • 274.
    Brasil, M. A. B.
    et al.
    Education Department, Industrial Technical School, Federal University of Santa Maria, Santa Maria, 97105-900, Brazil.
    Bösch, Bernhard
    Halmstad University, School of Information Technology.
    Wagner, F. R.
    Institute of Informatics, Federal University of Rio Grande Do sul, Porto Alegre, 91509-900, Brazil.
    De Freitas, E. P.
    Institute of Informatics, Federal University of Rio Grande Do sul, Porto Alegre, 91509-900, Brazil.
    Performance Comparison of Multi-Agent Middleware Platforms for Wireless Sensor Networks2018In: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 18, no 7, p. 3039-3049Article in journal (Refereed)
    Abstract [en]

    Despite the numerous possible applications of wireless sensor networks (WSNs), there is a key disadvantage related to the high complexity in programming WSNs, which is a result of their distributed and built-in features. To overcome this shortcoming, software agents have been identified as a suitable programming paradigm. The agent-based approach commonly uses a middleware for the execution of the software agents. In this regard, the present paper aims at comparing Java-based agent middleware platforms in their performance for the WSN application domain. Experiments were performed to analyze two versions of tracking applications, based on different agent models implemented for a given set of middleware platforms that support programming at a high-level of abstraction. The results highlight the differences in the resource consumption (CPU, memory, and energy) and in the communication overhead, providing an indication of suitability for each type of analyzed middleware, considering specific concerns while developing WSN applications. © 2001-2012 IEEE.

  • 275.
    Bredenfeldt, Karin
    et al.
    Halmstad University, School of Teacher Education (LUT).
    Ivansson, Sara
    Halmstad University, School of Teacher Education (LUT).
    Räkna med förskolan: En fenomenografisk studie om förskollärares uppfattningar av matematik i förskolan2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

     

    I denna studie har vi undersökt förskollärares uppfattningar av matematik i förskolan och deras uppfattningar av hur de arbetar med matematik i förskolans verksamhet.

    Vi har gjort kvalitativa intervjuer med fyra förskollärare på fyra olika förskolor. Dessa intervjuer har vi sedan bearbetat med hjälp av en fenomenografisk analysmetod. Resultatet visar många aspekter på hur förskollärare uppfattar att de arbetar med matematik i förskolan. Förskollärarna uppger att de arbetar med matematik i samtal tillsammans med barnen och att de benämner olika matematiska begrepp i vardagssituationer som t.ex. vid utdelning av frukt med förekommande frågor som: Hur stor bit vill du ha? Vill du ha en hel, en halv eller en fjärdedel av äpplet? Ett exempel som framkom på matematik i förskolan var i barnens lek. En förskollärare uppgav att ett matematiskt problemlösande kunde vara då barnen byggde koja tillsammans. Förskolläraren uppmuntrade barnen till att fundera på storlekar på filtar och andra material som de kunde tänkas behöva till bygget. När det gäller förskollärarnas arbetsätt så var det på många sätt olika men de tänkte likt om matematikarbetets betydelse för barnen i förskolan. Förskollärarna var alla överrens om att en tidig introduktion av matematik kan ge barnen en ökad förståelse för sin omvärld. Det framkommer även i resultatet att förskollärarnas egen inställning och erfarenheter har förändrats sedan de har fått mer kunskap om matematikämnet och detta har påverkat hur de arbetar med matematik i förskolans verksamhet.

  • 276.
    Bredstenslien, Julia
    Miljö-och hälsoskydd.
    VINDKRAFTSETABLERINGAR: EN JÄMFÖRANDE STUDIE OM NÄRBOENDES INSTÄLLNING TILL VINDKRAFT OCH VINDKRAFTSETABLERINGAR I SVERIGE OCH BRASILIEN2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To achieve a sustainable development, three aspects have to take equal place in the society; environmental, economical and social. To reduce the impact on the environment and the amount of greenhouse gases supplied to the atmosphere, industrialized countries and less developed countries must start cooperating. Also the use of renewable energy sources, like solar, hydro and wind power, have to increase.

    Wind power has great potential as a future energy supply. It is cost efficient, quickly developed and the resource is abundant and available worldwide.

    Examinations made in Sweden, indicates that there are difficulties establishing wind power at the same pace as the environmental goals, set by the Swedish government, requires. Mainly because people living nearby potential areas for wind power farms, appeal against the decision.

    This study aims to investigate differences between how people in Sweden and Brazil look at wind power as a future energy source and at the establishing process. It is divided in two parts, a Swedish literature study and a Brazilian study based on interviews with both local and governmental authorities and with people living nearby the wind power farm Osório.

    The Swedish study shows that the majority of people living nearby wind power farms are positive to wind power as a future energy source. The challenges lies in the establishing process because of fear of the consequences to the surrounding areas. The main concerns are:

     Changes in landscape

     Noise

     Visual effects

    Results from the Brazilian study indicate that 96 percent of the people living close to Osório were positive to wind power as a future energy source. 52 percent thought that the possibilities to be involved in the establishing process had been insufficient and that they were given to little opportunity to express their opinion. They did not experience any interference from the wind power farm and they thought that the landscape gave a clean impression.

    This study can be used to gain a more efficient expansion of wind power by an improvement of

  • 277.
    Brink, Johan
    et al.
    Halmstad University, School of Information Technology.
    Elvland, Erik
    Halmstad University, School of Information Technology.
    Hansson, Patrik
    Halmstad University, School of Information Technology.
    Effekterna av GDPR: En jämförelse mellan Personuppgiftslagen och den kommande allmänna dataskyddsförordningen.2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    On the 25th of May 2018 the Swedish Personal Data Act (Personuppgiftslagen, PuL) will be replaced by the EU-regulation General Data Protection Regulation (GDPR). The aim of this study was to determine the big differences between PuL and the GDPR while also looking at how organisations plan to handle the changes that the new regulation will bring. PuL and GDPRare in many ways similar but there are some major changes that will affect every person and every organisation within the EU/EES. The regulation will mean better and morecomprehensive rights for the individual, which in turn will result in higher requirements beingput on the companies who process personal data.

    The new requirements will result in extensive work within several areas to adapt to the new regulation. The legal and administrative sections will need to review their current contracts & agreements and update them if necessary. There may also need to implement technical solutionsto manage the requirements concerning “the right to be forgotten”, “data portability”, “recordkeeping” and the improved protection of personal data. According to the regulationorganisations are required to notify the supervisory authority of any data breach concerningpersonal data. The change in material scope will result in personal data stored in an unstructuredway being covered by the GDPR. To make companies follow the new legislation thesupervisory authority gains the power to levy significant fines if organisations violate the newregulation; in addition some organisations will need to appoint a “Data protection officer”that’ll monitor the processing of personal data.

    There are several factors that will determine the amount of work required to reach compliance;for example the size of the corporation and the extent of their current processing of personaldata.

    The attitude to the new regulation vary, those that take the regulation seriously have realisedthat there will be new demands put on their business, and have already started to adapt theirbusiness to reach compliance with the regulation. There are others that deem that they will notbe affected to the same extent and are therefore not as worried. In the great scope of things, theregulation will make the processing of personal data more secure within the EU/EES eventhough the peregrination to reach compliance may turn out to be a costly one.

  • 278.
    Bristav, Anton
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Svantesson, Max
    Halmstad University, School of Business, Engineering and Science.
    Viktiga kommunikationsfaktorer för ökad utsortering av matavfall2018Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    The environmental goal “God bebyggd miljö” states that 50 percent of the food waste should be collected, and 40 percent of it should go through biological treatment. This goal together with the prohibition on organic waste to landfill is a mean of control to get municipalities toimplement waste treatment systems for food waste. This study focused on what the localwaste treatment company in Halmstad municipality is doing to tackle the environmentalgoals and the system they’ve implemented, which is an optical sorting system. By talking to the local waste treatment company HEM (Halmstad Energi och Miljö AB) to get an idea of the current situation regarding what can be improved, the idea of communication aspects were brought up by the company as an area which could be developed and improved upon to increase the collection of food waste in the municipality.

    The study was conducted in mainly two ways. First a literature study and secondly interviews were conducted. The following questions were asked: Which communication factors areimportant and affect the result for a successful degree of sorting for the optical sorting system? What’s important to communicate to get customers to sort their waste correctly? How can the communication between the municipal waste treatment company and theinhabitants change over time to ensure a successful collection of food waste?

    The study resulted in an identification of different central components which are importantand affect the result for a successful waste collection - these are (1) audience targeting, (2) simplicity, (3) incentive, (4) continued communication (after the implementation of thesystem) and lastly (5) positive morale. To get customers to sort their waste correctly thestudy suggests that several of the central factors are included in the communication betweenthe municipality and the inhabitants. To also ensure a successful waste collection over timethe study also concluded that a continued communication is also needed.

    The conclusions drawn from the study is that the central factors gave good results for the interviewed municipalities and therefore would probably work for other municipalities.

  • 279.
    Brooks, Anthony
    et al.
    Aalborg University Esbjerg, Esbjerg, Denmark.
    Petersson, Eva
    Halmstad University, School of Information Technology.
    Recursive reflection and learning in raw data video analysis of interactive ’play’ environments for special needs health care2005In: Proceedings of 7th International Workshop on Enterprise networking and Computing in Healthcare Industry, 2005. HEALTHCOM 2005. / [ed] Heung Kook Choi, Piscataway, NJ: IEEE, 2005, p. 83-87, article id 1500399Conference paper (Refereed)
    Abstract [en]

    Technology influences the situation of people’s every day life and this, in turn, has an impact on opportunities for health related quality of life. This paper presents how findings from two separate and distinct feasibility investigations under the SoundScapes body of research corroborate an important aspect of the original methodology of the concept such as to have influenced its future design and application in its health field context. The primary purpose of the independent studies was to test the potential of utilizing sensor technology to empower control of multimedia feedback across different sample groups of abilities and to test the effects on these participants. © 2005 IEEE.

  • 280.
    Brooks, Eva
    et al.
    Aalborg University, Aalborg, Denmark.
    Sjöberg, Jeanette
    Halmstad University, School of Education, Humanities and Social Science, Centrum för lärande, kultur och samhälle (CLKS), Lärande, Profession och Samhällsutveckling.
    Evolving Playful and Creative Activities When School Children Develop Game-based Designs2019In: Interactivity, Game Creation, Design, Learning, and Innovation: 7th EAI International Conference, ArtsIT 2018, and 3rd EAI International Conference, DLI 2018, ICTCC 2018, Braga, Portugal, October 24–26, 2018, Proceedings / [ed] Anthony Brooks, Eva Books, Cristina Sylla, Heidelberg: Springer, 2019, p. 485-495Conference paper (Refereed)
    Abstract [en]

    The presence of digital technologies in classroom settings is relentlessly getting stronger and has shown to have powerful playful qualities. In recent years, digital game-based learning (DGBL) have been introduced in schools. In this paper we investigate an innovative approach to game-based learning, namely to use game design activities as motivators for developing children’s creative and social skills as well as other kinds of learning scenarios, e.g. computational. It is based on two cases, where game design activities by means of a narrative approach were applied in both analogue and digital form. The unit of analysis is game design activities. Hence, game design activities with the participating children (3 rd graders, 9–10 years of age), creative materials and technologies, and children’s actions as well as interactions are analyzed. The research questions posed in this study are: (1) What activities develop when school children design games in two cases, as an analogue activity, and as an activity including technology?; and (2) How do the learning environment, including the artefacts, employed mediate these activities? The outcomes of the study indicate that the game design workshop session which included both creative material and technology unfolded more combinational activities, which indicate that the inclusion of technology facilitated a more critical design decision making. However, the game design workshop session including only creative material exhibited a more thorough knowledge about what the material could do and what the children themselves could do with the material, which seemed to result in more playful interactions between the children. © 2019, ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering.

  • 281.
    Bråting, Kajsa
    et al.
    Uppsala universitet, Uppsala, Sverige.
    Sollervall, Håkan
    Linnéuniversitetet, Växjö, Sverige.
    Stadler, Erika
    Stockholms universitet, Stockholm, Sverige.
    Geometri för lärare2013 (ed. 1)Book (Other academic)
  • 282.
    Brönmark, Christer
    et al.
    Limnology, Department of Ecology, Lund University, Lund, Sweden.
    Weisner, Stefan E. B.
    Limnology, Department of Ecology, Lund University, Lund, Sweden.
    Indirect effects of fish community structure on submerged vegetation in shallow, eutrophic lakes: an alternative mechanism1992In: Hydrobiologia, ISSN 0018-8158, E-ISSN 1573-5117, Vol. 243/244, no 1, p. 293-301Article in journal (Refereed)
    Abstract [en]

    The loss of submerged macrophytes during eutrophication of shallow takes is a commonly observed phenomenon. The proximate reason for this decline is a reduction of available light due to increasing phytoplankton and/or epiphyton biomass. Here we argue that the ultimate cause for the transition from a macrophyte-dominated state to a phytoplankton-dominated state is a change in fish community structure. A catastrophic disturbance event (e.g. winterkill) acting selectively on piscivores, cascades down food chains, eventually reducing macrophyte growth through shading by epiphyton, an effect that is reinforced by increasing phytoplankton biomass. The transition back from the phytoplankton to the macrophyte state depends on an increase in piscivore standing stock and a reduction of planktivores. A conceptual model of these mechanisms is presented and supported by literature data and preliminary observations from a field experiment. © 1992 Kluwer Academic Publishers.

  • 283.
    Brönmark, Christer
    et al.
    Limnology, Department of Ecology, Lund University, Lund, Sweden.
    Weisner, Stefan E.B.
    Limnology, Department of Ecology, Lund University, Lund, Sweden.
    Decoupling of cascading trophic interactions in a freshwater, benthic food chain1996In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 108, no 3, p. 534-541Article in journal (Refereed)
    Abstract [en]

    Food chain theory provides explicit predictions for equilibrium biomasses among trophic levels in food chains of different lengths. Empirical studies on freshwater benthic food chains have typically been performed on chains with up to three levels and in field experiments with limited spatial and temporal scale. Here we use a ‘’natural snapshot experiment” approach to study equilibrium biomass and abundance among trophic levels in natural ponds differing only with respect to fish assemblage structure. Forty-four ponds were surveyed for their density and biomass of fish, snails and periphyton. Ponds were divided into three categories based on fish assemblage: ponds with no fish (two trophic levels), ponds with molluscivorous fish (three trophic levels), ponds with molluscivorous fish (three trophic levels) and ponds that also had piscivorous fish (four trophic levels). Ponds without fish had a high density and biomass of snails and a low biomass of periphyton, whereas snails with molluscivorous fish. In the presence of piscivores, molluscivore populations consisted of low numbers of large individuals. Snail assemblages in piscivore ponds were characterised by relatively high densities of small-bodied detritivorous species and periphyton biomass was not significantly different from ponds with three trophic levels. Thus, predictions from classic food chain theory were upheld in ponds with up to three trophic levels. In ponds with four trophic levels, however, there was a decoupling of the trophic cascade at the piscivore-molluscivore level. Gape-limited piscivory, predation on snails by molluscivores that have reached an absolute size refuge from predation, and changes in food preferences of the dominant snails are suggested to explain the observed patterns.

  • 284.
    Bukina, Elena
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Efficient Numerical Solution of PIDEs in Option Pricing2011Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
  • 285.
    Burestedt, E.
    et al.
    Department of Analytical Chemistry, University of Lund, Lund, Sweden.
    Emnéus, J.
    Department of Analytical Chemistry, University of Lund, Lund, Sweden.
    Gorton, L.
    Department of Analytical Chemistry, University of Lund, Lund, Sweden.
    Marko-Varga, G.
    Department of Analytical Chemistry, University of Lund, Lund, Sweden.
    Domínguez, E.
    Department of Analytical Chemistry, Faculty of Pharmacy, University of Alcalá de Henares, Alcalá de Henares, Spain.
    Ortega, F.
    Department of Analytical Chemistry, Faculty of Pharmacy, University of Alcalá de Henares, Alcalá de Henares, Spain.
    Narváez, A.
    Department of Analytical Chemistry, Faculty of Pharmacy, University of Alcalá de Henares, Alcalá de Henares, Spain.
    Irth, H.
    Division of Analytical Chemistry, Leiden/Amsterdam Center for Drug Research, Leiden, The Netherlands.
    Lutz, Mareike
    Division of Analytical Chemistry, Leiden/Amsterdam Center for Drug Research, Leiden, The Netherlands.
    Puig, D.
    Department of Environmental Chemistry, CID-CSIC, Barcelona, Spain.
    Barceló, D.
    Department of Environmental Chemistry, CID-CSIC, Barcelona, Spain.
    Optimisation and validation of an automated solid phase extraction technique coupled on-line to enzyme-based biosensor detection for the determination of phenolic compounds in surface water samples1995In: Chromatographia, ISSN 0009-5893, E-ISSN 1612-1112, Vol. 41, no 3-4, p. 207-215Article in journal (Refereed)
    Abstract [en]

    A fully integrated screening system for phenolic compounds was developed incorporating on-line solid phase extraction, fractionation and biosensor detection. Two different types of biosensors, solid graphite and carbon paste electrodes incorporating the enzyme tyrosinase, were compared and used in the screening system. Interfacing of the solid phase extraction and fractionation with the biosensor detection was given special attention since the biosensors were not compatible with the organic modifier used for desorption of phenols from the solid phase extraction step. The system was validated with conventional analytical techniques. Surface water samples from the Ebro river were spiked with 1,10, and 25μg L−1 of catechol, phenol,p-cresol, respectively. Three out of seven samples were spiked and the correct samples were identified, containing phenols equivalent to the spiked concentrations. © 1995 Friedr. Vieweg & Sohn Verlagsgesellschaft mbH.

  • 286.
    Burkhardt, J.
    et al.
    Institute for Crop Science and Resource Conservation, INRES-PE, University of Bonn, Karlrobert-Kreiten-Str. 13, 53115 Bonn, Germany.
    Flechard, C. R.
    Soils, Agronomy and Spatialization Unit, UMR-SAS, INRA, 65, rue de St-Brieuc, 35042 Rennes, France.
    Mattsson, Marie
    Plant and Soil Science Laboratory, University of Copenhagen (UoC), Faculty of Life Sciences, Thorvaldsensvej 40, 1871 Frederiksberg C, Copenhagen, Denmark.
    Gresens, F.
    Institute for Crop Science and Resource Conservation, INRES-PE, University of Bonn, Karlrobert-Kreiten-Str. 13, 53115 Bonn, Germany.
    Jongejan, P.A.C.
    Energy Research Centre of the Netherlands (ECN), Postbus 1, 1755 ZG Petten, The Netherlands.
    Erisman, J.W.
    Energy Research Centre of the Netherlands (ECN), Postbus 1, 1755 ZG Petten, The Netherlands.
    Weidinger, T.
    Department of Meteorology, Eötvös Loránd University (ELU), Budapest, Hungary.
    Meszaros, R.
    Department of Meteorology, Eötvös Loránd University (ELU), Budapest, Hungary.
    Nemitz, E.
    Centre for Ecology and Hydrology (CEH), Edinburgh Research Station, Bush Estate, Penicuik, Midlothian, EH26 0QB, UK.
    Sutton, M.A.
    Centre for Ecology and Hydrology (CEH), Edinburgh Research Station, Bush Estate, Penicuik, Midlothian, EH26 0QB, UK.
    Modelling the dynamic chemical interactions of atmospheric ammonia with leaf surface wetness in a managed grassland canopy2009In: Biogeosciences, ISSN 1726-4170, E-ISSN 1726-4189, Vol. 6, no 1, p. 67-84Article in journal (Refereed)
    Abstract [en]

    Ammonia exchange fluxes between grassland and the atmosphere were modelled on the basis of stomatal compensation points and leaf surface chemistry, and compared with measured fluxes during the GRAMINAE intensive measurement campaign in spring 2000 near Braunschweig, Germany. Leaf wetness and dew chemistry in grassland were measured together with ammonia fluxes and apoplastic NH4+ and H+ concentration, and the data were used to apply, validate and further develop an existing model of leaf surface chemistry and ammonia exchange. Foliar leaf wetness which is known to affect ammonia fluxes may be persistent after the end of rainfall, or sustained by recondensation of water vapour originating from the ground or leaf transpiration, so measured leaf wetness values were included in the model. pH and ammonium concentrations of dew samples collected from grass were compared to modelled values.

    The measurement period was divided into three phases: a relatively wet phase followed by a dry phase in the first week before the grass was cut, and a second drier week after the cut. While the first two phases were mainly characterised by ammonia deposition and occasional short emission events, regular events of strong ammonia emissions were observed during the post-cut period. A single-layer resistance model including dynamic cuticular and stomatal exchange could describe the fluxes well before the cut, but after the cut the stomatal compensation points needed to numerically match measured fluxes were much higher than the ones measured by bioassays, suggesting another source of ammonia fluxes. Considerably better agreement both in the direction and the size range of fluxes were obtained when a second layer was introduced into the model, to account for the large additional ammonia source inherent in the leaf litter at the bottom of the grass canopy. Therefore, this was found to be a useful extension of the mechanistic dynamic chemistry model by keeping the advantage of requiring relatively little site-specific information.

  • 287.
    Burnos, Sergey
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE). Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Ngow, ChaSing
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE). Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    SVI estimation of the implied volatility by Kalman filter.2010Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    To understand and model the dynamics of the implied volatility smile is essential for trading, pricing and risk management portfolio. We suggest a  linear Kalman filter for updating of the Stochastic Volatility Inspired (SVI) model of the volatility. From a risk management perspective we generate the 1-day ahead forecast of profit and loss (P\&L) of option portfolios. We compare the estimation of the implied volatility using the SVI model with the cubic polynomial model. We find that the SVI Kalman filter has outperformed the  others.

  • 288.
    Byttner, Stefan
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Holmberg, Ulf
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Wickström, Nicholas
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    An ion current algorithm for fast determination of high combustion variability2004Conference paper (Refereed)
    Abstract [en]

    It is desirable for an engine control system to maintain a stable combustion. A high combustion variability (typically measured by the relative variations in produced work, COV(IMEP)) can indicate the use of too much EGR or a too lean air-fuel mixture, which results in less engine efficiency(in terms of fuel and emissions) and reduced driveability. The coefficient of variation (COV) of the ion current integral has previously been shown in several papers to be correlated to the coefficient of variation of IMEP for various disturbances (e.g. AFR, EGR and fuel timing). This paper presents a cycle-to-cycle ion current based method of estimating the approximate category of IMEP (either normal burn, slow burn, partial burn or misfire) for the case of lean air-fuel ratio. The rate of appearance of the partial burn and misfire categories is then shown to be well correlated with the onset of high combustion variability(high COV(IMEP)). It is demonstrated that the detection of these categories can result in faster determination(prediction) of high variability compared to only using the COV(Ion integral). Copyright © 2004 SAE International.

  • 289.
    Byttner, Stefan
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Holmberg, Ulf
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Wickström, Nicholas
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Using Multiple Cylinder Ion Measurements for Improved Estimation of Combustion Variability2005In: Proceedings of the SAE 2005 World Congress & Exhibition, Warrendale, PA: SAE Inc. , 2005Conference paper (Refereed)
    Abstract [en]

    Estimation of combustion variability can be performed by using ion currents measured at the spark plug. A scheme is here proposed that exploits the potential of using measurements from multiple cylinders to improve the estimation accuracy of combustion variability (measured by the coefficient of variation of IMEP). This is realised by dividing combustion variability into categories and having one classifier running for each cylinder with the ion current as input signal. The final estimate of combustion variability is then formed by a majority vote among the classifiers. This scheme is shown to improve estimation accuracy by up to 15% on measurements taken from highway driving in a production vehicle.

  • 290.
    Byttner, Stefan
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Svensson, Magnus
    Volvo Technology, 405 08 Göteborg, Sweden.
    Vachkov, Gancho
    Reliability-based Information Systems Engineering, Kagawa University, 761-0396 Kagawa, Japan.
    Incremental classification of process data for anomaly detection based on similarity analysis2011In: EAIS 2011: 2011 IEEE Workshop on Evolving and Adaptive Intelligent Systems : April 11-15, 2011, Paris, France, Piscataway, N.J.: IEEE Press, 2011, p. 108-115Conference paper (Refereed)
    Abstract [en]

    Performance evaluation and anomaly detection in complex systems are time consuming tasks based on analyzing, similarity analysis and classification of many different data sets from real operations. This paper presents an original computational technology for unsupervised incremental classification of large data sets by using a specially introduced similarity analysis method. First of all the so called compressed data models are obtained from the original large data sets by a newly proposed sequential clustering algorithm. Then the datasets are compared by pairs not directly, but by using their respective compressed data models. The evaluation of the pairs is done by a special similarity analysis method that uses the so called Intelligent Sensors (Agents) and data potentials. Finally a classification decision is generated by using a predefined threshold of similarity. The applicability of the proposed computational scheme for anomaly detection, based on many available large data sets is demonstrated on an example of 18 synthetic data sets. Suggestions for further improvements of the whole computation technology and a better applicability are also discussed in the paper.

  • 291.
    Bärwald, Anton
    et al.
    Halmstad University, School of Information Technology.
    Aleksic, Jimmie
    Halmstad University, School of Information Technology.
    Felsökning av EtherNet/IP med cross-platform applikation2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the industry there is a need for a more efficient way to troubleshoot machines that uses the protocol EtherNet/IP. The current methods is time consuming and complex. This project gather data from a simulated network and analyze the data. The result of the analyze is presented on a cellphone application with a description and a possible solution. The application is a cross-platform application developed with Cordova. The simulated network is created on a Raspberry Pi 2. The analyze is done on another Raspberry Pi 2 running the software Node-RED. Communication between the simulated network Raspberry and the cellphone is with Bluetooth Low Energy. Communication between cellphone and the server is with MQTT. There are several areas where this kind of application may suit. This project is in one specific area – troubleshooting EtherNet/IP.

  • 292.
    Bååth, Lars B.
    Halmstad University, School of Business and Engineering (SET).
    3-dimensional imaging of refractory material at Pilkington Halmstad1996Report (Refereed)
  • 293.
    Bååth, Lars B.
    Halmstad University, School of Business and Engineering (SET).
    Delivery test of the EISCAT Svalbard Radar Antenna1996Report (Refereed)
  • 294.
    Bååth, Lars B.
    Onsala Space Observatory, Onsala, Sweden.
    mm VLBI1993In: VLBI Technology – Progress and Future Observational Possibilities: Proceedings of the International Symposium Held at Kyoto International Conference Hall on September 6-10, 1993 / [ed] Tetsuo Sasao, Seiji Manabe, Osamu Kameya & Makoto Inoue, Tokyo: Terra Scientific Publishing Company , 1993, p. 70-74Chapter in book (Refereed)
    Abstract [en]

    Very long Baseline Interferometry (VLBI) has now made its break-through into the mm wavelength regime. A global VLBI array has produced maps of radio sources at 3 mm since 1988 and development is under way to improve the sensitivity for VLBI also at 1 mm. This contribution discusses the present state of mm VLBI and the future developments.

  • 295.
    Bååth, Lars B.
    Halmstad University, School of Business and Engineering (SET).
    Tests of VLBI systems at Shanghai and Urumqi1996Report (Refereed)
  • 296.
    Bååth, Lars B.
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Buretta, Thomas A.
    Haystack Observatory.
    Clark, Thomas A.
    NASA Goddard Space Flight Center.
    Corey, Brian E.
    Haystack Observatory.
    Himwich, William E.
    NVI, Inc.lGoddard Space Flight Center.
    Ma, Chopo
    NASA Goddard Space Flight Center.
    Team China report1998Report (Refereed)
  • 297.
    Bååth, Lars
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Mantovani, F.
    Istituto di Radioastronomia del C.N.R., Bologna, Italy.
    Rantakyrö, F.T.
    Istituto di Radioastronomia del C.N.R., Bologna, Italy.
    High resolution interferometry of the QSO 1422+2021997In: Astronomy and Astrophysics. Supplement Series, ISSN 1286-4846, Vol. 125, no 1, p. 453-458Article in journal (Refereed)
    Abstract [en]

    We present VLA A-array observations at 8.4 and 15GHz and European VLBI Network (EVN) observations at 1.6GHz of the radio source 1422+202. It is suggested that 1422+202 is a Medium-size Object in the evolutionary sequence from Compact Steep-spectrum Sources to larger sized radio sources. The VLBI data were analysed with the phase referencing technique and we show that the EVN can work as a phase stable instrument for separations between the calibrator source and the target source up to ~ 10 degrees. With the VLA and VLBI observations we investigate some of the issues about the nucleus of 1422+202 and we discuss the possible cause for the low frequency variability detected while monitoring the source.

  • 298.
    Bååth, L.B.
    Onsala Space Observatory, Chalmers University of Technology, Gothenburg, Sweden.
    A closer look at active galactic nuclei — the great engines of the universe1992In: Physica scripta. T, ISSN 0281-1847, Vol. T43, p. 57-66Article in journal (Refereed)
    Abstract [en]

    The intensive radio emission from powerful radio galaxies and quasars Make these attractive candidates to become "standard candles" to probe the Universe. This paper discusses this possibility and the physics of the radio sources.

  • 299.
    Bååth, L.B.
    Onsala Space Observatory, Onsala, Sweden.
    AGN Variability and VLBI1994In: Multi-Wavelength Continuum Emission of Agn: Proceedings of the 159th Symposium of the International Astronomical Union, Held in Geneva, Switzerland, August 30 – September 3, 1993 / [ed] T.J.-L. Courvoisier & A. Blecha, Dordrecht: Kluwer Academic Publishers, 1994, p. 181-186Chapter in book (Refereed)
    Abstract [en]

    This contribution discusses the connection between variability in radio and optical with structural variations observed with VLBI. Structural changes do not have to start in the core, and intensity variations may be caused by components in the jet outside the core. The scenario is probably more complicated than present day theories assume.

  • 300.
    Bååth, L.B.
    Onsala Space Observatory, Chalmers University of Technology, Gothenburg, Sweden.
    Astrophysical global interferometry at Onsala Space Observatory1982In: Reports from the Observatory of Lund, ISSN 0349-4217, Vol. 18, p. 23-25Article in journal (Refereed)
3456789 251 - 300 of 1867
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