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  • 1.
    Ahlgren, Bengt
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Hurtig, Per
    Karlstad University, Sweden.
    Abrahamsson, Henrik
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Grinnemo, Karl-Johan
    Karlstad University, Sweden.
    Brunstrom, Anna
    Karlstad University, Sweden.
    ICN congestion control for wireless links2018Conference paper (Refereed)
    Abstract [en]

    Information-centric networking (ICN) with its design around named-based forwarding and in-network caching holds great promises to become a key architecture for the future Internet. Many proposed ICN hop-by-hop congestion control schemes assume a fixed and known link capacity, which rarely - if ever - holds true for wireless links. Firstly, we demonstrate that although these congestion control schemes are able to fairly well utilise the available wireless link capacity, they greatly fail to keep the delay low. In fact, they essentially offer the same delay as in the case with no hop-by-hop, only end-to-end, congestion control. Secondly, we show that by complementing these schemes with an easy-to-implement, packet-train capacity estimator, we reduce the delay to a level significantly lower than what is obtained with only end-to-end congestion control, while still being able to keep the link utilisation at a high level.

  • 2.
    Ahrentorp, Fredrik
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Blomgren, Jacob
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Jonasson, Christian
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Sarwe, Anna
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Sepehri, Sobhan
    Chalmers University of Technology, Sweden.
    Eriksson, Emil
    Chalmers University of Technology, Sweden.
    Kalaboukhov, Alexei
    Chalmers University of Technology, Sweden.
    Jesorka, Aldo
    Chalmers University of Technology, Sweden.
    Winkler, Dag
    Chalmers University of Technology, Sweden.
    Schneiderman, Justin F.
    University of Gothenburg, Sweden.
    Nilsson, Mats
    Stockholm University, Sweden.
    Albert, Jan
    Karolinska University Hospital, Sweden ; Karolinska Institutet, Sweden.
    de la Torre, Theresa Z. G.
    Uppsala University, Sweden.
    Strømme, Maria
    Uppsala University, Sweden.
    Johansson, Christer
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Sensitive magnetic biodetection using magnetic multi-core nanoparticles and RCA coils2017In: Journal of Magnetism and Magnetic Materials, ISSN 0304-8853, E-ISSN 1873-4766, Vol. 427, p. 14-18Article in journal (Refereed)
    Abstract [en]

    We use functionalized iron oxide magnetic multi-core particles of 100 nm in size (hydrodynamic particle diameter) and AC susceptometry (ACS) methods to measure the binding reactions between the magnetic nanoparticles (MNPs) and bio-analyte products produced from DNA segments using the rolling circle amplification (RCA) method. We use sensitive induction detection techniques in order to measure the ACS response. The DNA is amplified via RCA to generate RCA coils with a specific size that is dependent on the amplification time. After about 75 min of amplification we obtain an average RCA coil diameter of about 1 µm. We determine a theoretical limit of detection (LOD) in the range of 11 attomole (corresponding to an analyte concentration of 55 fM for a sample volume of 200 µL) from the ACS dynamic response after the MNPs have bound to the RCA coils and the measured ACS readout noise. We also discuss further possible improvements of the LOD.

  • 3.
    Alcusa-Saez, E. P.
    et al.
    Departamento de Física Aplicada y Electromagnetismo-ICMUV, Spain.
    Diez, A.
    Departamento de Física Aplicada y Electromagnetismo-ICMUV, Spain.
    Rivera-Perez, E.
    Departamento de Física Aplicada y Electromagnetismo-ICMUV, Spain.
    Margulis, Walter
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Norin, Lars
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Andres, M. V.
    Departamento de Física Aplicada y Electromagnetismo-ICMUV, Spain.
    All-fiber acousto-optic tunable filter in polyimide coated optical fibers2017In: International Conference on Transparent Optical Networks, 2017Conference paper (Refereed)
    Abstract [en]

    We present the experimental demonstration of in-fiber acousto-optic coupling in a polyimide-coated optical fiber. Although the presence of the polyimide coating increases is significantly the attenuation of the acoustic wave, we show that acousto-optic interaction can still be produced with reasonable efficiency. The effect of the polyimide coating on the acousto-optic interaction process is analyzed in detailed. Theoretical and experimental results are in good agreement. To our knowledge, this is the first experimental demonstration of acousto-optic coupling in optical fibers with robust protective coating.

  • 4.
    Alcusa-Sáez, E. P.
    et al.
    Departamento de Física Aplicada y Electromagnetismo-ICMUV, Spain.
    Díez, Antonio
    Departamento de Física Aplicada y Electromagnetismo-ICMUV, Burjassot, Spain.
    Rivera-Pérez, E.
    Departamento de Física Aplicada y Electromagnetismo-ICMUV, Spain.
    Margulis, Walter
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH Royal Institute of Technology, Sweden.
    Norin, L.
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH Royal Institute of Technology, Sweden.
    Andrés, M. V.
    Departamento de Física Aplicada y Electromagnetismo-ICMUV, Spain.
    Acousto-optic interaction in polyimide coated optical fibers with flexural waves2017In: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 25, no 15, p. 17167-17173Article in journal (Refereed)
    Abstract [en]

    Acousto-optic coupling in polyimide-coated single-mode optical fibers using flexural elastic waves is demonstrated. The effect of the polyimide coating on the acousto-optic interaction process is analyzed in detailed. Theoretical and experimental results are in good agreement. Although the elastic attenuation is significant, we show that acousto-optic coupling can be produced with a reasonably good efficiency. To our knowledge, it is the first experimental demonstration of acousto-optic coupling in optical fibers with robust protective coating.

  • 5.
    Allison, R.S.
    et al.
    York University, Canada.
    Brunnstrom, Kjell
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Chandler, D.M.
    Shizuoka University, Japan.
    Colett, H.
    Intel Corp, US.
    Corriveau, P.
    Intel Corp, US.
    Daly, S.
    Dolby Laboratories Inc, US.
    Goel, J.
    Qualcomm Technologies, Inc, US.
    Long, J.Y.
    Intel Corp, US.
    Wilcox, L.M.
    York University, Canada.
    Yaacob, Y.
    Shizuoka University, Japan.
    Yang, S. N.
    Pacific University, US.
    Zhang, Y.
    Xi’an Jiaotong University, China.
    Perspectives on the definition of visually lossless quality for mobile and large format displays2018In: Journal of Electronic Imaging, Vol. 27, no 5, article id 053035Article in journal (Refereed)
    Abstract [en]

    Advances in imaging and display engineering have given rise to new and improved image and videoapplications that aim to maximize visual quality under given resource constraints (e.g., power, bandwidth).Because the human visual system is an imperfect sensor, the images/videos can be represented in a mathematicallylossy fashion but with enough fidelity that the losses are visually imperceptible—commonly termed“visually lossless.” Although a great deal of research has focused on gaining a better understanding ofthe limits of human vision when viewing natural images/video, a universally or even largely accepted definitionof visually lossless remains elusive. Differences in testing methodologies, research objectives, and targetapplications have led to multiple ad-hoc definitions that are often difficult to compare to or otherwise employ inother settings. We present a compendium of technical experiments relating to both vision science and visualquality testing that together explore the research and business perspectives of visually lossless image quality,as well as review recent scientific advances. Together, the studies presented in this paper suggest that a singledefinition of visually lossless quality might not be appropriate; rather, a better goal would be to establish varyinglevels of visually lossless quality that can be quantified in terms of the testing paradigm.

  • 6.
    Andersson Ersman, Peter
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Westerberg, David
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Tu, Deyu
    Linköping University, Sweden.
    Nilsson, Marie
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Åhlin, Jessica
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Eveborn, Annelie
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Lagerlöf, Axel
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Nilsson, David
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Sandberg, Mats
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Norberg, Petronella
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Berggren, Magnus
    Linköping University, Sweden.
    Forchheimer, Robert
    RISE - Research Institutes of Sweden, ICT, SICS.
    Gustafsson, Göran
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Screen printed digital circuits based on vertical organicelectrochemical transistors2017In: Flex. Print. Electron., Vol. 2, article id 045008Article in journal (Refereed)
    Abstract [en]

    Vertical organic electrochemical transistors (OECTs) have been manufactured solely using screenprinting. The OECTs are based on PEDOT:PSS (poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonic acid)), which defines the active material for both the transistor channel and the gateelectrode. The resulting vertical OECT devices and circuits exhibit low-voltage operation, relativelyfast switching, small footprint and high manufacturing yield; the last three parameters are explainedby the reliance of the transistor configuration on a robust structure in which the electrolyte verticallybridges the bottom channel and the top gate electrode. Two different architectures of the verticalOECT have been manufactured, characterized and evaluated in parallel throughout this report. Inaddition to the experimental work, SPICE models enabling simulations of standalone OECTs andOECT-based circuits have been developed. Our findings may pave the way for fully integrated, lowvoltageoperating and printed signal processing systems integrated with e.g. printed batteries, solarcells, sensors and communication interfaces. Such technology can then serve a low-cost basetechnology for the internet of things, smart packaging and home diagnostics applications.

  • 7. Andersson, J. A.
    et al.
    Arvidsson, A.
    Du, Manxing
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Zhang, Huiming
    RISE, Swedish ICT, Acreo.
    Kihl, M.
    Host, S.
    Lagerstedt, Chhristina
    RISE, Swedish ICT, Acreo.
    User profiling for pre-fetching or caching in a catch-up TV network2016In: IEEE International Symposium on Broadband Multimedia Systems and Broadcasting, BMSB, 2016Conference paper (Refereed)
    Abstract [en]

    We investigate the potential of different pre-fetching and/or caching strategies for different user behaviour with respect to surfing or browsing in a catch-up-TV network. To this end we identify accounts and channels associated with strong or weak surfing or browsing respectively and study the distributions of hold times for the different types of behaviour. Finally we present results from a request prediction model and a caching simulation for the different types of behaviour and find that the results are relatively similar. © 2016 IEEE.

  • 8.
    Arndt, Holger
    et al.
    Spring Techno GmbH & Co, Germany..
    Burkard, Stefan
    Spring Techno GmbH & Co, Germany..
    Talavera, Guillermo
    Universitat Autònoma de Barcelona, Spain.
    Garcia, Joan
    Universitat Autònoma de Barcelona, Spain.
    Castells, David
    Universitat Autònoma de Barcelona, Spain.
    Codina, Marc
    Universitat Autònoma de Barcelona, Spain.
    Hausdorff, Jeffrey
    Mirelman, Anat
    Tel Aviv Sourasky Medical Center, Israel.
    Harte, Richard
    National University of Ireland, Ireland.
    Casey, Monica
    National University of Ireland, Ireland.
    Glynn, Liam
    National University of Ireland, Ireland.
    Di Rosa, Mirko
    Istituto Nazionale Riposo e Cura per Anziani, Italy.
    Rossi, Lorena
    Istituto Nazionale Riposo e Cura per Anziani, Italy.
    Stara, Vera
    Istituto Nazionale Riposo e Cura per Anziani, Italy.
    Rösevall, John
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Rusu, Cristina
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Carenas, Carlos
    EURECAT, Spain.
    Breuil, Fanny
    EURECAT, Spain.
    Reixach, Elisenda
    EURECAT, Spain.
    Carrabina, Jordi
    Universitat Autònoma de Barcelona, Spain.
    Real-time constant monitoring of fall risk index by means of fully-wireless insoles2017Conference paper (Refereed)
    Abstract [en]

    Constant monitoring of gait in real life conditions is considered the best way to assess Fall Risk Index (FRI) since most falls happen out of the ideal conditions in which clinicians are currently analyzing the patient's behavior. This paper presents the WIISEL platform and results obtained through the use of the first full-wireless insole devices that can measure almost all gait related data directly on the feet (not in the upper part of the body as most existing wearable solutions). The platform consists of a complete tool-chain: insoles, smartphone & app, server & analysis tool, FRI estimation and user access. Results are obtained by combining parameters in a personalized way to build individual fall risk index assessed by experts with the help of data analytics. New FRI has been compared with standards that validate the quality of its prediction in a statistically significant way. That qualitatively relevant information is being provided to the platform users, being either end-users/patients, relatives or caregivers and the related clinicians to ideally assess about their long term evolution. © 2017 The authors and IOS Press.

  • 9. Arndt, S.
    et al.
    Brunnström, Kjell
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Cheng, E.
    Engelke, U.
    Moller, S.
    Antons, J. -N
    Review on using physiology in quality of experience2016In: Human Vision and Electronic Imaging 2016, HVEI 2016, 2016, p. 197-205Conference paper (Refereed)
    Abstract [en]

    In the area of Quality of Experience (QoE), one challenge is to design test methodologies in order to evaluate the perceived quality of multimedia content delivered through technical sys-tems. Traditionally, this evaluation is done using subjective opinion tests. However, sometimes it is difficult for observers to communicate the experienced quality through the given scale. Fur-thermore. those tests do not give insights into how the user is reacting on an internal physiological level. To overcome these issues, one approach is to use physiological measures, in order to derive a direct non-verbal response of the recipient. In this paper, we review studies that have been performed in the domain of QoE using physiological measures and we look into current activities in standardization bodies. We present challenges this research faces. and give an overview on what researchers should be aware of when they want to start working in this research area.

  • 10.
    Bender, P.
    et al.
    University of Cantabria, Spain.
    Balceris, C.
    University of Cantabria, Spain.
    Ludwig, F.
    TU Braunschweig, Germany.
    Posth, O.
    Physikalisch-Technische Bundesanstalt, Germany.
    Bogart, L. K.
    University College London, UK.
    Szczerba, W.
    Bundesanstalt für Materialforschung und -prüfung, Germany ; AGH University of Science and Technology, Poland .
    Castro, A.
    SOLVE Research and Consultancy AB, Sweden.
    Nilsson, L.
    SOLVE Research and Consultancy AB, Sweden ; Lund University, Sweden.
    Costo, R.
    Instituto de Ciencia de Materiales de Madrid, Spain.
    Gavilán, H.
    Instituto de Ciencia de Materiales de Madrid, Spain.
    González-Alonso, D.
    University of Cantabria, Spain.
    Pedro, I. D.
    University of Cantabria, Spain.
    Barquin, L. F.
    University of Cantabria, Spain.
    Johansson, C.
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Distribution functions of magnetic nanoparticles determined by a numerical inversion method2017In: New Journal of Physics, ISSN 1367-2630, E-ISSN 1367-2630, Vol. 19, no 7, article id 073012Article in journal (Refereed)
    Abstract [en]

    In the present study, we applied a regularized inversion method to extract the particle size, magnetic moment and relaxation-time distribution of magnetic nanoparticles from small-angle x-ray scattering (SAXS), DC magnetization (DCM) and AC susceptibility (ACS) measurements. For the measurements the particles were colloidally dispersed in water. At first approximation the particles could be assumed to be spherically shaped and homogeneously magnetized single-domain particles. As model functions for the inversion, we used the particle form factor of a sphere (SAXS), the Langevin function (DCM) and the Debye model (ACS). The extracted distributions exhibited features/peaks that could be distinctly attributed to the individually dispersed and non-interacting nanoparticles. Further analysis of these peaks enabled, in combination with a prior characterization of the particle ensemble by electron microscopy and dynamic light scattering, a detailed structural and magnetic characterization of the particles. Additionally, all three extracted distributions featured peaks, which indicated deviations of the scattering (SAXS), magnetization (DCM) or relaxation (ACS) behavior from the one expected for individually dispersed, homogeneously magnetized nanoparticles. These deviations could be mainly attributed to partial agglomeration (SAXS, DCM, ACS), uncorrelated surface spins (DCM) and/or intra-well relaxation processes (ACS). The main advantage of the numerical inversion method is that no ad hoc assumptions regarding the line shape of the extracted distribution functions are required, which enabled the detection of these contributions. We highlighted this by comparing the results with the results obtained by standard model fits, where the functional form of the distributions was a priori assumed to be log-normal shaped.

  • 11.
    Bender, P.
    et al.
    University of Cantabria, Spain .
    Bogart, L. K.
    University College London, UK .
    Posth, O.
    Physikalisch-Technische Bundesanstalt, Germany .
    Szczerba, W.
    Bundesanstalt für Materialforschung Und-prüfung (BAM), Germany ; AGH University of Science and Technology, Poland .
    Rogers, S. E.
    ISIS-STFC Neutron Scattering Facility, UK.
    Castro, A.
    SOLVE Research and Consultancy AB, Sweden .
    Nilsson, L.
    SOLVE Research and Consultancy AB, Sweden ; Lund University, Sweden .
    Zeng, L. J.
    Chalmers University of Technology, Sweden .
    Sugunan, Abhilash
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Sommertune, Jens
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Fornara, A.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    González-Alonso, D.
    University of Cantabria, Spain .
    Fernández Barquín, L.
    University of Cantabria, Spain .
    Johansson, Christer
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Structural and magnetic properties of multi-core nanoparticles analysed using a generalised numerical inversion method2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, article id 45990Article in journal (Refereed)
    Abstract [en]

    The structural and magnetic properties of magnetic multi-core particles were determined by numerical inversion of small angle scattering and isothermal magnetisation data. The investigated particles consist of iron oxide nanoparticle cores (9 nm) embedded in poly(styrene) spheres (160 nm). A thorough physical characterisation of the particles included transmission electron microscopy, X-ray diffraction and asymmetrical flow field-flow fractionation. Their structure was ultimately disclosed by an indirect Fourier transform of static light scattering, small angle X-ray scattering and small angle neutron scattering data of the colloidal dispersion. The extracted pair distance distribution functions clearly indicated that the cores were mostly accumulated in the outer surface layers of the poly(styrene) spheres. To investigate the magnetic properties, the isothermal magnetisation curves of the multi-core particles (immobilised and dispersed in water) were analysed. The study stands out by applying the same numerical approach to extract the apparent moment distributions of the particles as for the indirect Fourier transform. It could be shown that the main peak of the apparent moment distributions correlated to the expected intrinsic moment distribution of the cores. Additional peaks were observed which signaled deviations of the isothermal magnetisation behavior from the non-interacting case, indicating weak dipolar interactions.

  • 12.
    Bender, P.
    et al.
    Universidad de Cantabria, Spain.
    Fock, J.
    TNU Technical University of Denmark, Denmark.
    Hansen, M. F.
    TNU Technical University of Denmark, Denmark.
    Bogart, L. K.
    University College London, UK.
    Southern, P.
    University College London, UK.
    Ludwig, F.
    Technische Universität Braunschweig, Germany.
    Wiekhorst, F.
    Physikalisch-Technische Bundesanstalt, Germany.
    Szczerba, W.
    Bundesanstalt für Materialforschung und -prüfung, Germany; AGH University of Science and Technology, Poland.
    Zeng, L. J.
    Chalmers University of Technology, Sweden.
    Heinke, D.
    nanoPET Pharma GmbH, Germany.
    Gehrke, N.
    nanoPET Pharma GmbH, Germany.
    Díaz, M. T. F.
    Institut Laue Langevin, France.
    González-Alonso, D.
    Universidad de Cantabria, Spain.
    Espeso, J. I.
    Universidad de Cantabria, Spain.
    Fernández, J. R.
    Universidad de Cantabria, Spain.
    Johansson, Christer
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Influence of clustering on the magnetic properties and hyperthermia performance of iron oxide nanoparticles2018In: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 29, no 42, article id 425705Article in journal (Refereed)
    Abstract [en]

    Clustering of magnetic nanoparticles can drastically change their collective magnetic properties, which in turn may influence their performance in technological or biomedical applications. Here, we investigate a commercial colloidal dispersion (FeraSpin™R), which contains dense clusters of iron oxide cores (mean size around 9 nm according to neutron diffraction) with varying cluster size (about 18-56 nm according to small angle x-ray diffraction), and its individual size fractions (FeraSpin™XS, S, M, L, XL, XXL). The magnetic properties of the colloids were characterized by isothermal magnetization, as well as frequency-dependent optomagnetic and AC susceptibility measurements. From these measurements we derive the underlying moment and relaxation frequency distributions, respectively. Analysis of the distributions shows that the clustering of the initially superparamagnetic cores leads to remanent magnetic moments within the large clusters. At frequencies below 105 rad s-1, the relaxation of the clusters is dominated by Brownian (rotation) relaxation. At higher frequencies, where Brownian relaxation is inhibited due to viscous friction, the clusters still show an appreciable magnetic relaxation due to internal moment relaxation within the clusters. As a result of the internal moment relaxation, the colloids with the large clusters (FS-L, XL, XXL) excel in magnetic hyperthermia experiments.

  • 13.
    Bender, Philipp
    et al.
    Universidad de Cantabria, Spain.
    Fock, Jeppe
    Technical University of Denmark, Denmark.
    Frandsen, Cathrine
    Technical University of Denmark, Denmark.
    Hansen, Mikkel F.
    Technical University of Denmark, Denmark.
    Balceris, Christoph
    TU Braunschweig, Germany.
    Ludwig, Frank
    TU Braunschweig, Germany.
    Posth, Oliver
    Physikalisch-Technische Bundesanstalt, Germany.
    Wetterskog, Erik
    Uppsala University, Sweden.
    Bogart, Lara K.
    University College London, UK.
    Southern, Paul
    University College London, UK.
    Szczerba, Wojciech
    Bundesanstalt für Materialforschung und -prüfung, Germany ; AGH University of Science and Technology, Poland.
    Zeng, Lunjie
    Chalmers University of Technology, Sweden.
    Witte, Kerstin
    University of Rostock, Germany ; Micromod Partikeltechnologie GmbH, Germany.
    Gruettner, Cordula
    Micromod Partikeltechnologie GmbH, Germany.
    Westphal, Fritz
    Micromod Partikeltechnologie GmbH, Germany.
    Honecker, Dirk
    Institut Laue-Langevin, France.
    Gonzalez-Alonso, David
    Universidad de Cantabria, Spain.
    Fernandez Barquin, Luis
    Universidad de Cantabria, Spain.
    Johansson, Christer
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Relating Magnetic Properties and High Hyperthermia Performance of Iron Oxide Nanoflowers2018In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 122, no 5, p. 3068-3077Article in journal (Refereed)
    Abstract [en]

    We investigated, in depth, the interrelations among structure, magnetic properties, relaxation dynamics and magnetic hyperthermia performance of magnetic nanoflowers. The nanoflowers are about 39 nm in size, and consist of densely packed iron oxide cores. They display a remanent magnetization, which we explain by the exchange coupling between the cores, but we observe indications for internal spin disorder. By polarized small-angle neutron scattering, we unambiguously confirm that, on average, the nano flowers are preferentially magnetized along one direction. The extracted discrete relaxation time distribution of the colloidally dispersed particles indicates the presence of three distinct relaxation contributions. We can explain the two slower processes by Brownian and classical Neel relaxation, respectively. The additionally observed very fast relaxation contributions are attributed by us to the relaxation of disordered spins within the nanoflowers. Finally, we show that the intrinsic loss power (ILP, magnetic hyperthermia performance) of the nanoflowers measured in colloidal dispersion at high frequency is comparatively large and independent of the viscosity of the surrounding medium. This concurs with our assumption that the observed relaxation in the high frequency range is primarily a result of internal spin relaxation, and possibly connected to the disordered spins within the individual nanoflowers.

  • 14.
    Berto, Marcello
    et al.
    Università di Modena e Reggio Emilia, Italy.
    Diacci, Chiara
    Linköping University, Sweden.
    Theuer, Lorenz
    RISE - Research Institutes of Sweden, ICT, Acreo. Linköping University, Sweden.
    Di Lauro, Michele
    Università di Modena e Reggio Emilia, Italy.
    Simon, Daniel T.
    Linköping University, Sweden.
    Berggren, Magnus
    Linköping University, Sweden.
    Biscarini, Fabio
    Università di Modena e Reggio Emilia, Italy ; stituto Italiano di Tecnologia—Center for Translational Neurophysiology, Italy.
    Beni, Valerio
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Bortolotti, Carlo A.
    Università di Modena e Reggio Emilia, Italy.
    Label free urea biosensor based on organic electrochemical transistors2018In: Flexible and Printed Electronics, ISSN 2058-8585, Vol. 3, no 2, article id 024001Article in journal (Refereed)
    Abstract [en]

    The quantification of urea is of the utmost importance not only in medical diagnosis, where it serves as a potential indicator of kidney and liver disfunction, but also in food safety and environmental control. Here, we describe a urea biosensor based on urease entrapped in a crosslinked gelatin hydrogel, deposited onto a fully printed PEDOT:PSS-based organic electrochemical transistor (OECT). The device response is based on the modulation of the channel conductivity by the ionic species produced upon urea hydrolysis catalyzed by the entrapped urease. The biosensor shows excellent reproducibility, a limit of detection as low as 1 μM and a response time of a few minutes. The fabrication of the OECTs by screen-printing on flexible substrates ensures a significant reduction in manufacturing time and costs. The low dimensionality and operational voltages (0.5 V or below) of these devices contribute to make these enzymatic OECT-based biosensors as appealing candidates for high-throughput monitoring of urea levels at the point-of-care or in the field.

  • 15.
    Blomgren, Jakob
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Ahrentorp, Fredrik
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Ilver, Dag
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Jonasson, Christian
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Sepehri, Sobhan
    Chalmers University of Technology, Sweden.
    Kalaboukhov, Alexei
    Chalmers University of Technology, Sweden.
    Winkler, Dag
    Chalmers University of Technology, Sweden.
    de la Torre, Tereza
    Uppsala University, Sweden.
    Strømme, Maria
    Uppsala University, Sweden.
    Johansson, Christer
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Development of a sensitive induction-based magnetic nanoparticle biodetection method2018In: Nanomaterials, ISSN 2079-4991, Vol. 8, no 11, article id 887Article in journal (Refereed)
    Abstract [en]

    We developed a novel biodetection method for influenza virus based on AC magnetic susceptibility measurement techniques (the DynoMag induction technique) together with functionalized multi-core magnetic nanoparticles. The sample consisting of an incubated mixture of magnetic nanoparticles and rolling circle amplified DNA coils is injected into a tube by a peristaltic pump. The sample is moved as a plug to the two well-balanced detection coils and the dynamic magnetic moment in each position is read over a range of excitation frequencies. The time for making a complete frequency sweep over the relaxation peak is about 5 minutes (10 Hz–10 kHz with 20 data points). The obtained standard deviation of the magnetic signal at the relaxation frequency (around 100 Hz) is equal to about 10−5 (volume susceptibility SI units), which is in the same range obtained with the DynoMag system. The limit of detection with this method is found to be in the range of 1 pM. © 2018 by the authors. Licensee MDPI, Basel, Switzerland.

  • 16.
    Brinkfeldt, Klas
    et al.
    RISE - Research Institutes of Sweden, Swerea, Swerea IVF.
    Wetter, Göran
    RISE - Research Institutes of Sweden, Swerea, Swerea IVF.
    Lövberg, Andreas
    RISE - Research Institutes of Sweden, Swerea, Swerea IVF.
    Tegehall, Per-Erik
    RISE - Research Institutes of Sweden, Swerea, Swerea IVF.
    Andersson, Dag
    RISE - Research Institutes of Sweden, Swerea, Swerea IVF.
    Goncalves, Johnny
    NOTE Norrtelje AB, Sweden.
    Söderlund, Jonas
    NOTE Norrtelje AB, Norrtälje, Sweden.
    Strandberg, Jan
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Kwarnmark, Mikael
    Cogra Pro AB, Sweden.
    Feasibility of PCB-integrated vibration sensors for condition monitoring of electronic systems2018In: ASME 2018 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems, InterPACK 2018, 2018Conference paper (Refereed)
    Abstract [en]

    The increasing complexity of electronics in systems used in safety critical applications, such as for example self-driving vehicles requires new methods to assure the hardware reliability of the electronic assemblies. Prognostics and Health Management (PHM) that uses a combination of data-driven and Physics-of-Failure models is a promising approach to avoid unexpected failures in the field. However, to enable PHM based partly on Physics-of-Failure models, sensor data that measures the relevant environment loads to which the electronics is subjected during its mission life are required. In this work, the feasibility to manufacture and use integrated sensors in the inner layers of a printed circuit board (PCB) as mission load indicators measuring impacts and vibrations has been investigated. A four-layered PCB was designed in which piezoelectric sensors based on polyvinylidenefluoride-co-trifluoroethylene (PVDF-TrFE) were printed on one of the laminate layers before the lamination process. Manufacturing of the PCB was followed by the assembly of components consisting of BGAs and QFN packages in a standard production reflow soldering process. Tests to ensure that the functionality of the sensor material was unaffected by the soldering process were performed. Results showed a yield of approximately 30 % of the sensors after the reflow soldering process. The yield was also dependent on sensor placement and possibly shape. Optimization of the sensor design and placement is expected to bring the yield to 50 % or better. The sensors responded as expected to impact tests. Delamination areas were present in the test PCBs, which requires further investigation. The delamination does not seem to be due to the presence of embedded sensors alone but rather the result of a combination of several factors. The conclusion of this work is that it is feasible to embed piezoelectric sensors in the layers of a PCB.

  • 17.
    Brooke, Robert
    et al.
    Linköping University, Sweden.
    Mitraka, Evangelie
    Linköping University, Sweden.
    Sardar, Samim
    Linköping University, Sweden.
    Sandberg, Mats
    RISE - Research Institutes of Sweden, ICT, Acreo. Linköping University, Sweden.
    Sawatdee, Anurak
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Berggren, Magnus
    RISE - Research Institutes of Sweden, ICT, Acreo. Linköping University, Sweden.
    Crispin, Xavier
    Linköping University, Sweden.
    Jonsson, Magnus P.
    Linköping University, Sweden.
    Infrared electrochromic conducting polymer devices2017In: Journal of Materials Chemistry C, ISSN 2050-7526, E-ISSN 2050-7534, Vol. 5, no 23, p. 5824-5830Article in journal (Refereed)
    Abstract [en]

    The conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) is well known for its electrochromic properties in the visible region. Less focus has been devoted to the infrared (IR) wavelength range, although tunable IR properties could enable a wide range of novel applications. As an example, modern day vehicles have thermal cameras to identify pedestrians and animals in total darkness, but road and speed signs cannot be easily visualized by these imaging systems. IR electrochromism could enable a new generation of dynamic road signs that are compatible with thermal imaging, while simultaneously providing contrast also in the visible region. Here, we present the first metal-free flexible IR electrochromic devices, based on PEDOT:Tosylate as both the electrochromic material and electrodes. Lateral electrochromic devices enabled a detailed investigation of the IR electrochromism of thin PEDOT:Tosylate films, revealing large changes in their thermal signature, with effective temperature changes up to 10 °C between the oxidized (1.5 V) and reduced (-1.5 V) states of the polymer. Larger scale (7 × 7 cm) vertical electrochromic devices demonstrate practical suitability and showed effective temperature changes of approximately 7 °C, with good optical memory and fast switching (1.9 s from the oxidized state to the reduced state and 3.3 s for the reversed switching). The results are highly encouraging for using PEDOT:Tosylate for IR electrochromic applications.

  • 18.
    Brunnstrom, Kjell
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo. Mid Sweden University, Sweden.
    Barkowsky, Marcus
    Deggendorf Institute of Technology (DIT), University of Applied Sciences Deggendorf, Germany.
    Statistical quality of experience analysis: on planning the sample size and statistical significance testing2018In: Journal of Electronic Imaging (JEI), ISSN 1017-9909, E-ISSN 1560-229X, Vol. 27, no 5, article id 053013Article in journal (Refereed)
    Abstract [en]

    This paper analyzes how an experimenter can balance errors in subjective video quality tests betweenthe statistical power of finding an effect if it is there and not claiming that an effect is there if the effect is not there,i.e., balancing Type I and Type II errors. The risk of committing Type I errors increases with the number ofcomparisons that are performed in statistical tests. We will show that when controlling for this and at thesame time keeping the power of the experiment at a reasonably high level, it is unlikely that the number oftest subjects that are normally used and recommended by the International Telecommunication Union (ITU),i.e., 15 is sufficient but the number used by the Video Quality Experts Group (VQEG), i.e., 24 is more likelyto be sufficient. Examples will also be given for the influence of Type I error on the statistical significance ofcomparing objective metrics by correlation. We also present a comparison between parametric and nonparametricstatistics. The comparison targets the question whether we would reach different conclusions on the statisticaldifference between the video quality ratings of different video clips in a subjective test, based on thecomparison between the student T-test and the Mann–Whitney U-test. We found that there was hardly a differencewhen few comparisons are compensated for, i.e., then almost the same conclusions are reached. Whenthe number of comparisons is increased, then larger and larger differences between the two methods arerevealed. In these cases, the parametric T-test gives clearly more significant cases, than the nonparametrictest, which makes it more important to investigate whether the assumptions are met for performing a certaintest.

  • 19.
    Brunnstrom, Kjell
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo. Mid Sweden University, Sweden.
    Wang, Kun
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Tavakoli, Samira
    Universidad Politecnica de Madrid, Spain.
    Andren, Börje
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Symptoms analysis of 3D TV viewing based on Simulator SicknessQuestionnaires2017In: Quality and User Experience, ISSN 2366-0139, E-ISSN 2366-0147, Vol. 2Article in journal (Refereed)
    Abstract [en]

    Stereoscopic 3D TV viewing puts differentvisual demands on the viewer compared to 2D TV viewing.Previous research has reported on viewers’ fatigue anddiscomfort and other negative effects. This study is toinvestigate further how severe and what symptoms mayarise from somewhat longish 3D TV viewing. The MPEG3DV project is working on the next-generation videoencoding standard and in this process, MPEG issued a callfor proposal of encoding algorithms. To evaluate thesealgorithms a large scale subjective test was performedinvolving Laboratories all over the world [(MPEG 2011;Baroncini 2012)]. For the participating Labs, it wasoptional to administer a slightly modified Simulator SicknessQuestionnaire (SSQ) before and after the test. One ofthe SSQ data sets described in this article is coming fromthis study. The SSQ data from the MPEG test is the largestdata set in this study and also contains the longest viewingtimes. Along with the SSQ data from the MPEG test, wehave also collected questionnaire data in three other 3D TVstudies. We did two on the same 3D TV (passive filmpattern retarder) as in the MPEG test, and one was using aprojector system. As comparison SSQ data from a 2Dvideo quality experiment is also presented. This investigationshows a statistically significant increase in symptomsafter viewing 3D TV primarily related to the visual or Oculomotor system. Surprisingly, 3D video viewing usingprojectors did not show this effect.

  • 20.
    Brunnström, Kjell
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Allison, R. S.
    York University, Canada.
    Chandler, D. M.
    Shizuoka University, Japan.
    Colett, H.
    Intel Corp, US.
    Corriveau, P.
    Intel Corp, US.
    Daly, S.
    Dolby Laboratories, US.
    Goel, J.
    Qualcomm, Display Video Processing Group, Canada.
    Knopf, J.
    Intel Corp, US.
    Wilcox, L. M.
    York University, Canada.
    Yaacob, Y.
    Shizuoka University, Japan.
    Yang, S. -N
    Pacific University, US.
    Zhang, Y.
    Shizuoka University, Japan.
    Industry and business perspectives on the distinctions between visually lossless and lossy video quality: Mobile and large format displays2017In: IS and T International Symposium on Electronic Imaging Science and Technology, 2017, p. 118-133Conference paper (Refereed)
    Abstract [en]

    This paper will explore the mobile and business perspectives of visually lossless image quality, as well as review recent scientific advances. It is the outcome from the Special Session on Visually Lossless Video Quality for Modern Devices: Research and Industry Perspectives organized at the Human Vision and Electronic Imaging 2017 by IS&T at San Francisco Airport, Burlingame, California, USA, Jan 29 - Feb 2, 2017. It summarizes four presentations and a panel discussion.

  • 21.
    Brunnström, Kjell
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Barkowsky, Marcus
    Balancing type I errors and statistical power in video quality assessment2017In: IS and T International Symposium on Electronic Imaging Science and Technology, 2017, p. 91-96Conference paper (Refereed)
    Abstract [en]

    This paper analyzes how an experimenter can balance errors in subjective video quality tests between the statistical power of finding an effect if it is there and not claiming that an effect is there if the effect it is not there i.e. balancing Type I and Type II errors. The risk of committing Type I errors increases with the number of comparisons that are performed in statistical tests. We will show that when controlling for this and at the same time keeping the power of the experiment at a reasonably high level, it will require more test subjects than are normally used and recommended by international standardization bodies like the ITU. Examples will also be given for the influence of Type I error on the statistical significance of comparing objective metrics by correlation.

  • 22.
    Carlsson, Raul
    et al.
    RISE - Research Institutes of Sweden, Swerea, Swerea SWECAST.
    Elmquist, Lennart
    RISE - Research Institutes of Sweden, Swerea, Swerea SWECAST.
    Johansson, Christian
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Cast metal with intelligence - from passive to intelligent cast components2017In: 8th Conference on Smart Structures and Materials, SMART 2017 and 6th International Conference on Smart Materials and Nanotechnology in Engineering, SMN 2017, 2017, p. 550-560Conference paper (Refereed)
    Abstract [en]

    The paper describes an innovation project aiming to embed sensors into cast metal during the casting process. Important measurands are e.g. elongation, shear, temperature and vibration. In practice this means to turn metal components into also being digital components. This will respond to some of metal industrýs challenges; resource efficient design, increased value added for the casting sector, and general access to different possibilities of digitalization. Technical challenges lie in choices of sensor material to integrate during the casting process that maintains its sensor functionality after casting processing without degrading the mechanical strength of the metal component. Other challenges relate to signal interaction and interference between sensor and metal. To handle the technical challenges the innovation project gathers competence about metal casting and sensor technology. One goal of this innovation project is to develop an innovation platform that elevates the material based casting industry into a wholly or partially value and service based industry. Integration of sensors into cast components makes sensing functionality a natural property of metal, which in turn may turn metal into key components for the industrial digitalization.

  • 23.
    Carlsson, Raul
    et al.
    RISE - Research Institutes of Sweden, Swerea, Swerea SWECAST.
    Elmquist, Lennart
    RISE - Research Institutes of Sweden, Swerea, Swerea SWECAST.
    Thore, Andreas
    RISE - Research Institutes of Sweden, Swerea, Swerea SWECAST.
    Ahrentorp, Fredrik
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Johansson, Christer
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Israelsson, Björn
    SKF Mekan AB, Sweden.
    Connecting sensors inside smart castings2018Conference paper (Refereed)
    Abstract [en]

    The paper presents ongoing research on smart metal castings, meaning the technologicalinnovation of elevating cast metal components into metal components with integratedsensor functionality. Since the innovation targets aim straight at low cost industrial serialproduction, specific high cost and high-end solutions like inclusion of advancedelectronic equipment and after mounted sensors are not part of this innovationdevelopment. Integrating signal carriers inside metal castings to achieve metal castingswith sensor functionality requires robust solutions for connecting the sensor signal to thesensor interrogator and interpreter. The actual transmission of the signal may be donewirelessly or by wire. However, for several reasons there is a challenge with establishingan isolated and distinct connection between the sensor contact, and the contact at theexternal connection, regardless of whether it is to an antenna for wireless transmission orto a wire. This paper presents metallurgical challenges associated with choices ofmaterials, and combinations of metallurgical challenges and production process relatedchallenges, including the high melting temperatures. Aims are to find the rightcombinations of metal alloys, production simplicity, signal stability and robustness. Thepaper will present some of the tests made in the project so far. The project is run in aconsortium of the two Sweden-based industrial companies Husqvarna and SKF, and thetwo Swedish research institutes Swerea SWECAST and RISE Acreo.

  • 24.
    Chamania, Mohit
    et al.
    ADVA Optical Networking, Germany.
    Szyrkowiec, Thomas
    ADVA Optical Networking, Germany.
    Santuari, Michele
    CREATE-NET Research Center, Italy.
    Siracusa, Dominico
    CREATE-NET Research Center, Italy.
    Autenrieth, Achim
    ADVA Optical Networking, Germany.
    Lopez, Victor
    Telefónica I+D, Spain.
    Sköldström, Pontus
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Junique, Stephane
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Intent-based in-flight service encryption in multi-layer transport networks2017In: 2017 Optical Fiber Communications Conference and Exhibition, OFC 2017 - Proceedings, 2017Conference paper (Refereed)
    Abstract [en]

    We demonstrate multi-layer encrypted service provisioning via the ACINO orchestrator. ACINO combines a novel intent interface with an ONOS-based SDN orchestrator to facilitate encrypted services at IP, Ethernet and optical network layers.

  • 25.
    Chen, XÍ
    et al.
    Huazhong University of Science and Technology, China.
    Lin, Rui
    Huazhong University of Science and Technology, China.
    Cui, Jingxian
    Huazhong University of Science and Technology, China.
    Gan, Li
    Huazhong University of Science and Technology, China.
    Pang, Xiaodan
    KTH Royal Institute of Technology, Sweden.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Udalcovs, Aleksejs
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Jiang, Tao
    Huazhong University of Science and Technology, China.
    Schatz, Richard
    KTH Royal Institute of Technology, Sweden.
    Popov, Sergei
    KTH Royal Institute of Technology, Sweden.
    Chena, Jiajia
    KTH Royal Institute of Technology, Sweden.
    Tang, Ming
    Huazhong University of Science and Technology, China.
    Fu, Songnian
    Huazhong University of Science and Technology, China.
    Liu, Deming
    Huazhong University of Science and Technology, China.
    TDHQ Enabling Fine-granularity Adaptive Loading for SSB-DMT Systems2018In: IEEE Photonics Technology Letters, ISSN 1041-1135, E-ISSN 1941-0174, Vol. 30, no 19, p. 1687-1690Article in journal (Refereed)
    Abstract [en]

    In this letter, we introduce time domain hybrid quadrature amplitude modulation (TDHQ) for the single sideband (SSB) discrete multi-tone (DMT) systems. Experimental results reveal that with a single precoding set and the proposed adaptive loading algorithm, the TDHQ scheme can achieve finer granularity and therefore smoother continuous growth of data rate than that with the conventional quadrature amplitude modulation (QAM). Besides, thanks to the frame construction and the tailored mapping rule, the scheme with TDHQ has an obviously better peak to average power ratio (PAPR).

  • 26.
    Cristofori, Valentina
    et al.
    Technical University of Denmark, Denmark.
    Da Ros, Francescos
    Technical University of Denmark, Denmark.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Chaibi, Mohamed E.
    FOTON Laboratory, France.
    Bramerie, Laurent
    FOTON Laboratory, France.
    Ding, Yunhong
    Technical University of Denmark, Denmark.
    Pang, Xiadon
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Shen, Alexandre
    Thales, France.
    Gallet, Antonin
    Thales, France.
    Duan, Guang-Hua
    Thales, France.
    Hassan, Karem
    III-V Lab, France.
    Olivier, Segolene
    III-V Lab, France.
    Popov, Sergei
    KTH - Royal Institute of Technology, Sweden.
    Jacobsen, Gunnar
    Oxenløwe, Leif K.
    Technical University of Denmark, Denmark.
    Peucheret, Christophe
    FOTON Laboratory, France.
    25-Gb/s transmission over 2.5-km SSMF by silicon MRR enhanced 1.55-μm III-V/SOI DML2017In: IEEE Photonics Technology Letters, ISSN 1041-1135, E-ISSN 1941-0174, Vol. 29, no 12, p. 960-963, article id 7917280Article in journal (Refereed)
    Abstract [en]

    The use of a micro-ring resonator (MRR) to enhance the modulation extinction ratio and dispersion tolerance of a directly modulated laser is experimentally investigated with a bit rate of 25 Gb/s as proposed for the next generation data center communications. The investigated system combines a 11-GHz 1.55-μm directly modulated hybrid III-V/SOI DFB laser realized by bonding III-V materials (InGaAlAs) on a silicon-on-insulator (SOI) wafer and a silicon MRR also fabricated on SOI. Such a transmitter enables error-free transmission (BER < 10-9) at 25 Gb/s data rate over 2.5-km standard single mode fiber without dispersion compensation nor forward error correction. As both laser and MRR are fabricated on the SOI platform, they could be combined into a single device with enhanced performance, thus providing a cost-effective transmitter for short reach applications.

  • 27.
    Czegledi, Christian B.
    et al.
    Chalmers University of Technology, Sweden.
    Karlsson, Magnus
    Chalmers University of Technology, Sweden.
    Johannisson, Pontus
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Agrell, Erik
    Chalmers University of Technology, Sweden.
    Temporal stochastic channel model for absolute polarization state and polarization-mode dispersion2017In: 2017 Optical Fiber Communications Conference and Exhibition, OFC 2017 - Proceedings, 2017Conference paper (Refereed)
    Abstract [en]

    We propose and validate a discrete-time channel model for the temporal drift of the absolute polarization state and polarization-mode dispersion for coherent fiber optic systems. The model can be used in simulations to test and develop DSP for coherent receivers.

  • 28.
    Da Ros, Francesco
    et al.
    Technical University of Denmark, Denmark.
    Cristofori, Valentina
    Technical University of Denmark, Denmark.
    Ozolins, Oskars
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Chaibi, Mohamed E.
    University of Rennes, France.
    Pang, Xiodan
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Jacobsen, Gunnar
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Popov, Sergei
    KTH Royal Institute of Technology, Sweden.
    Galili, Michael
    Technical University of Denmark, Denmark.
    Oxenløwe, Leif K.
    Technical University of Denmark, Denmark.
    Peucheret, Christophe
    University of Rennes, France.
    4-PAM dispersion-uncompensated transmission with micro-ring resonator enhanced 1.55-μm DML2017In: Optics InfoBase Conference Papers, 2017, article id STu1M.5.Conference paper (Refereed)
    Abstract [en]

    Real-time transmission of 14-GBd 4-PAM signal is demonstrated by combining a commercial 1.55-μm DML with a silicon MRR. BER below the HD-FEC threshold is measured after 26-km SSMF transmission without offline digital signal processing.

  • 29.
    Del Rosso, Tommaso
    et al.
    Pontifícia Universidade Católica do Rio de Janeiro, Brazil.
    Margulis, Walter
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Fontana, Jake
    Naval Research Laboratory, US.
    Carvalho, Isabel C.S.
    Pontifícia Universidade Católica do Rio de Janeiro, Brazil.
    10 - Plasmonics for the Characterization of Metal Organic Films and Nanoparticles2019In: Metal Nanostructures for Photonics, Elsevier , 2019, p. 223-259Chapter in book (Other academic)
    Abstract [en]

    Here, we present an overview of the ellipsometric characterization of hybrid thin films and metal nanoparticles by surface plasmon resonance (SPR) spectroscopy, together with the dynamic control of the optical properties of the latter for applications in optoelectronic devices. A description of traditional techniques used for the determination of the thickness and refractive index of organic thin films deposited over the SPR planar sensing platforms is presented, with a discussion of the most recent applications in the ellipsometric characterization of thin film of metal nanoparticles and graphene layers. We conclude by describing recent results developing a dynamically tunable plasmonic pixel, where the electric-field-controlled alignment of gold nanorods in a colloidal suspension can enable optical switching at frequencies greater than megahertz.

  • 30.
    D'Humières, Benoit
    et al.
    TEMATYS, France.
    Esmiller, Bruno
    Airbus Safran Launchers SAS, France.
    Gouy, Yann
    Airbus Safran Launchers SAS, France.
    Steck, Emilie
    Airbus Safran Launchers SAS, France.
    Quintana, Crisanto
    Univ. of Oxford, United Kingdom.
    Faulkner, Graham
    Univ. of Oxford, United Kingdom.
    O'Brien, Dominic
    Univ. of Oxford, United Kingdom.
    Sproll, Fabian
    Deutsches Zentrum für Luft- und Raumfahrt e.V., Germany.
    Wagner, Paul
    Deutsches Zentrum für Luft- und Raumfahrt e.V., Germany.
    Hampf, Daniel
    Deutsches Zentrum für Luft- und Raumfahrt e.V., Germany.
    Riede, Wolfgang
    Deutsches Zentrum für Luft- und Raumfahrt e.V., Germany.
    Salter, Michael
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Wang, Qin
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Platt, Duncan
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Jakonis, Darius
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Piao, Xiaoyu
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Karlsson, Mikael
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Oberg, Olof
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Petermann, Ingemar
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Michalkiewicz, Aneta
    Astri Polska Sp., Poland.
    Krezel, Jerzy
    Astri Polska Sp., Poland.
    Debowska, Anna
    Astri Polska Sp., Poland.
    Thueux, Yoann
    Airbus Group Innovations, United Kingdom.
    The C3PO project: A laser communication system concept for small satellites2017In: Proceedings of SPIE - The International Society for Optical Engineering, 2017Conference paper (Refereed)
    Abstract [en]

    The satellite market is shifting towards smaller (micro and nanosatellites), lowered mass and increased performance platforms. Nanosatellites and picosatellites have been used for a number of new, innovative and unique payloads and missions. This trend requires new concepts for a reduced size, a better performance/weight ratio and a reduction of onboard power consumption. In this context, disruptive technologies, such as laser-optical communication systems, are opening new possibilities. This paper presents the C3PO1 system, "advanced Concept for laser uplink/ downlink CommuniCation with sPace Objects", and the first results of the development of its key technologies. This project targets the design of a communications system that uses a ground-based laser to illuminate a satellite, and a Modulating Retro-Reflector (MRR) to return a beam of light modulated by data to the ground. This enables a downlink, without a laser source on the satellite. This architecture suits well to small satellite applications so as high data rates are potentially provided with very low board mass. C3PO project aims to achieve data rates of 1Gbit/s between LEO satellites and Earth with a communication payload mass of less than 1kilogram. In this paper, results of the initial experiments and demonstration of the key technologies will be shown.

  • 31.
    Edberg, Jesper
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo. Linköping University, Sweden.
    Inganas, Olle
    Linköping University, Sweden.
    Engquist, Isak
    Linköping University, Sweden.
    Berggren, Magnus
    Linköping University, Sweden ; Stellenbosch University, South Africa.
    Boosting the capacity of all-organic paper supercapacitors using wood derivatives2018In: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 6, no 1, p. 145-152Article in journal (Refereed)
    Abstract [en]

    Printed and flexible organic electronics is a steadily expanding field of research and applications. One of the most attractive features of this technology is the possibility of large area and high throughput production to form low-cost electronics on different flexible substrates. With an increasing demand for sustainable energy production, low-cost and large volume technologies to store high-quality energy become equally important. These devices should be environmentally friendly with respect to their entire life cycle. Supercapacitors and batteries based on paper hold great promise for such applications due to the low cost and abundance of cellulose and other forest-derived components. We report a thick-film paper-supercapacitor system based on cellulose nanofibrils, the mixed ion-electron conducting polymer PEDOT: PSS and sulfonated lignin. We demonstrate that the introduction of sulfonated lignin into the cellulose-conducting polymer system increases the specific capacitance from 110 to 230 F g(-1) and the areal capacitance from 160 mF cm(-2) to 1 F cm(-2). By introducing lignosulfonate also into the electrolyte solution, equilibrium, with respect to the concentration of the redox molecule, was established between the electrode and the electrolyte, thus allowing us to perform beyond 700 charge/discharge cycles with no observed decrease in performance.

  • 32.
    Edström, Adam
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Målberg, Sofia
    RISE - Research Institutes of Sweden, ICT, Acreo.
    The Strategic Research Agenda for the Swedish Additive Metal Manufacturing Industry2018Other (Other (popular science, discussion, etc.))
  • 33.
    Elahipanah, H.
    et al.
    Ascatron AB, Sweden.
    Thierry-Jebali, N.
    Ascatron AB, Sweden.
    Reshanov, S. A.
    Ascatron AB, Sweden.
    Kaplan, W.
    Ascatron AB, Sweden.
    Zhang, A.
    Ascatron AB, Sweden.
    Lim, J. -K
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Bakowski, M.
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Östling, M.
    KTH Royal Institute of Technology, Sweden.
    Schöner, A.
    Ascatron AB, Sweden.
    Design optimization of a high temperature 1.2 kV 4H-SiC buried grid JBS rectifier2017In: 11th European Conference on Silicon Carbide and Related Materials, ECSCRM 2016, 2017, p. 455-458Conference paper (Refereed)
    Abstract [en]

    1.2 kV SiC buried grid junction barrier Schottky (BG-JBS) diodes are demonstrated. The design considerations for high temperature applications are investigated. The design is optimized in terms of doping concentration and thickness of the epilayers, as well as grid size and spacing dimensions, in order to obtain low on-resistance and reasonable leakage current even at high temperatures. The device behavior at temperatures ranging from 25 to 250ºC is analyzed and measured on wafer level. The forward voltage drop of 1.1 V at 100 A/cm2 and 3.8 V at 1000 A/cm2 is measured, respectively. At reverse voltage of 1 kV, a leakage current density below 0.1 μA/cm2 and below 0.1 mA/cm2 is measured at 25 and 250ºC, respectively. This proves the effective shielding effect of the BG-JBS design and provides benefits in high voltage applications, particularly for high temperature operation.

  • 34.
    Elmquist, Lennart
    et al.
    RISE - Research Institutes of Sweden, Swerea, Swerea SWECAST.
    Carlsson, Raul
    RISE - Research Institutes of Sweden, Swerea, Swerea SWECAST.
    Johansson, Christer
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Cast iron components with intelligence2018Conference paper (Refereed)
    Abstract [en]

    The paper describes a project with the aim to develop communicating and functional cast iron components in smart systems. The concept is based on sensors integrated into cast iron components; this will influence not only the component but also the casting process. Among the technical challenges is how to choose a sensor solution that cost-efficiently and with minimal environmental impact can be integrated into the component during the casting process, and especially without being damaged during mold filling and the high pouring temperature. Another challenge is how the iron will interact and interfere with sensor signals and whether an insulating intermediate material is needed or not. Integrating the sensors into the casting makes sensors a natural part of the component, which in turn can lead to more resource efficient designs, increased value added for the casting sector, and a general access to different possibilities of digitalization. The integrated sensors can be used for effective control and monitoring of components when in service and give information about for example how the component is used and what conditions it is exposed to. In other words, the component can tell when maintenance is needed or in worst cases, indicate that something is wrong before a failure will happen. Important measurands can e.g. be elongation, shear, temperature and vibration. Different combinations of sensor materials and insulating materials and their interaction with the cast iron have been investigated. It is shown how the interaction at the interface affects the microstructure and consequently the properties of the cast iron. In the case of insulating materials it is e.g. shown how air gaps are formed and in the case of sensor materials it is shown how a diffusion zone is formed and how this zone depends on the sensor material. How this diffusion zone affects the microstructure is discussed.

  • 35.
    Engelke, Ulrich
    et al.
    Commonwealth Scientific and Industrial Research Organisation, Australia.
    Darcy, Daniel P.
    Dolby Laboratories, USA.
    Mulliken, Grant H.
    Dolby Laboratories, USA.
    Bosse, Sebstian
    Fraunhofer Institute for Telecommunications, Berlin, German.
    Martini, Maria G.
    Kingston University, U.K..
    Arndt, Sebstian
    Norwegian University of Science and Technology, Norway.
    Antons, Jan Niklas
    Technische Universiät Berlin, Germany.
    Chan, Kit Y.
    Curtin University, Australia.
    Ramzan, Naeem
    University of the West of Scotland, UK.
    Brunnstrom, Kjell
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Psychophysiology-Based QoE Assessment: A Survey2017In: IEEE Journal on Selected Topics in Signal Processing, ISSN 1932-4553, E-ISSN 1941-0484, Vol. 11, no 1, p. 6-21, article id 7569001Article in journal (Refereed)
    Abstract [en]

    We present a survey of psychophysiology-based assessment for quality of experience (QoE) in advanced multimedia technologies. We provide a classification of methods relevant to QoE and describe related psychological processes, experimental design considerations, and signal analysis techniques. We summarize multimodal techniques and discuss several important aspects of psychophysiology-based QoE assessment, including the synergies with psychophysical assessment and the need for standardized experimental design. This survey is not considered to be exhaustive but serves as a guideline for those interested to further explore this emerging field of research.

  • 36. Etcheverry, S.
    et al.
    Faridi, A.
    Ramachandraiah, H.
    Margulis, Walter
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Laurell, F.
    Russom, A.
    All fiber based micro-flow cytometer by combining optical fiber with inertial focusing2016In: 20th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2016, 2016, p. 1655-1656Conference paper (Refereed)
    Abstract [en]

    Towards a portable point of care flow cytometry platform, we present here an integrated all optical fiber-based optofluidic system capable of counting and discriminating fluorescent particles and cells. The robust and compact device incorporates optical fibers and circular capillaries to build an all-fiber optofluidic device to enable counting particles based on their fluorescent and back-scatter light emission. Here, we combine this with inertial- and elasto-inertial microfluidics for sheathless particle and cell focusing for integrated detection with scattering and fluorescence detections - all necessary components of standard cytometers. We validated the system for cell counting based on scattering and fluorescence.

  • 37.
    Etcheverry, S.
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH, Royal Institute of Technology, Sweden..
    Russom, A.
    KTH, Royal Institute of Technology, Sweden..
    Laurell, F.
    KTH, Royal Institute of Technology, Sweden..
    Margulis, W.
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH, Royal Institute of Technology, Sweden..
    Trapping and optical identification of microparticles in a liquid with a functional optical fiber probe2018In: Conference on Lasers and Electro-Optics OSA Technical Digest (online) (Optical Society of America, 2018), paper AM4P.6, 2018Conference paper (Refereed)
    Abstract [en]

    A fiber probe traps single micrometer-particles by fluid suction into a hollow microstructure and enables optical identification by the fluorescence light collected in a fiber core. The probe finds applications in life-science and environmental monitoring.

  • 38.
    Etcheverry, Sebastian
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH Royal Institute of Technology, Sweden.
    Araujo, Leonardo F.
    Pontifícia Universidade Católica do Rio de Janeiro (PUC-RIO), Brazil.
    Carvalho, Isabel C. S.
    Pontifícia Universidade Católica do Rio de Janeiro (PUC-RIO), Brazil.
    Margulis, Walter
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH Royal Institute of Technology, Sweden.
    Fontana, Jake
    Naval Research Laboratory, US.
    Digital electric field induced switching of plasmonic nanorods using an electro-optic fluid fiber2017In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 111, no 22, article id 221108Article in journal (Refereed)
    Abstract [en]

    We demonstrate the digital electric field induced switching of plasmonic nanorods between "1" and "0" orthogonal aligned states using an electro-optic fluid fiber component. We show by digitally switching the nanorods that thermal rotational diffusion of the nanorods can be circumvented, demonstrating an approach to achieve submicrosecond switching times. We also show, from an initial unaligned state, that the nanorods can be aligned into the applied electric field direction in 110 ns. The high-speed digital switching of plasmonic nanorods integrated into an all-fiber optical component may provide opportunities for remote sensing and signaling applications. © 2017 Author(s).

  • 39.
    Etcheverry, Sebastian
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH Royal Institute of Technology, Sweden.
    Araujo, Leonardo F.
    Pontificia Universidade Católica do Rio de Janeiro, Brazil.
    da Costa, Greice K. B.
    Rural Federal University of Rio de Janeiro, Brazil.
    Pereira, Joao M. B.
    Pontificia Universidade Católica do Rio de Janeiro, Brazil.
    Camara, Alexandre R.
    Universidade do Estado do Rio de Janeiro, Brazil.
    Naciri, Jawad
    Naval Research Laboratory, USA.
    Ratna, Banahalli R.
    Naval Research Laboratory, USA.
    Hernández-Romano, Ivan
    University of Guanajuato, Mexico ; Mackenzie Presbyterian University, Brazil.
    de Matos, Cristiano J. S.
    Mackenzie Presbyterian University, Brazil.
    Carvalho, Isabel C. S.
    Pontificia Universidade Católica do Rio de Janeiro, Brazil.
    Margulis, Walter
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH Royal Institute of Techology, Sweden.
    Fontana, Jake
    Naval Research Laboratory, USA.
    Microsecond switching of plasmonic nanorods in an all-fiber optofluidic component2017In: Operator Theory: Advances and Applications, ISSN 1004-4469, E-ISSN 2334-2536, Vol. 4, no 8, p. 864-870Article in journal (Refereed)
    Abstract [en]

    As information technologies move from electron- to photon-based systems, the need to rapidly modulate light is of paramount importance. Here, we study the evolution of the electric-field-induced alignment of gold nanorods suspended in organic solvents. The experiments were performed using an all-fiber optofluidic device, which enables convenient interaction of light, electric fields, and the nanorod suspension. We demonstrate microsecond nanorod switching times, three orders of magnitude faster than a traditional Freederickcz-based liquid crystal alignment mechanism. We find that the dynamics of the alignment agrees well with the Einstein–Smoluchowski relationship, allowing for the determination of the rotational diffusion coefficient and polarizability anisotropy of the nanorods as well as the effective length of the ligands capping the nanorods. The ability to dynamically control the optical properties of these plasmonic suspensions coupled with the point-to-point delivery of light from the fiber component, as demonstrated in this work, may enable novel ultrafast optical switches, filters, displays, and spatial light modulators.

  • 40.
    Etcheverry, Sebastian
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH Royal Institute of Technology, Sweden.
    Faridi, A.
    KTH Royal Institute of Technology, Sweden.
    Ramachandraiah, H.
    KTH Royal Institute of Technology, Sweden.
    Kumar, T.
    KTH Royal Institute of Technology, Sweden.
    Margulis, Walter
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH Royal Institute of Technology, Sweden.
    Laurell, F.
    KTH Royal Institute of Technology, Sweden.
    Russom, A.
    KTH Royal Institute of Technology, Sweden.
    High performance micro-flow cytometer based on optical fibres2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, no 1, article id 5628Article in journal (Refereed)
    Abstract [en]

    Flow cytometry is currently the gold standard for analysis of cells in the medical laboratory and biomedical research. Fuelled by the need of point-of-care diagnosis, a significant effort has been made to miniaturize and reduce cost of flow cytometers. However, despite recent advances, current microsystems remain less versatile and much slower than their large-scale counterparts. In this work, an all-silica fibre microflow cytometer is presented that measures fluorescence and scattering from particles and cells. It integrates cell transport in circular capillaries and light delivery by optical fibres. Single-stream cell focusing is performed by Elasto-inertial microfluidics to guarantee accurate and sensitive detection. The capability of this technique is extended to high flow rates (up to 800 μl/min), enabling a throughput of 2500 particles/s. The robust, portable and low-cost system described here could be the basis for a point-of-care flow cytometer with a performance comparable to commercial systems. © 2017 The Author(s).

  • 41.
    Etcheverry, Sebastian
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH Royal Institute of Technology, Sweden.
    Russom, A.
    KTH Royal Institute of Technology, Sweden.
    Laurell, F.
    KTH Royal Institute of Technology, Sweden.
    Margulis, Walter
    RISE - Research Institutes of Sweden, ICT, Acreo. KTH Royal Institute of Technology, Sweden.
    Fluidic trapping and optical detection of microparticles with a functional optical fiber2017In: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 25, no 26, p. 33657-33663Article in journal (Refereed)
    Abstract [en]

    A fiber probe is presented that traps single micro-sized particles and allows detection of their optical properties. The trapping mechanism used is based on fluid suction with a micro-structured optical fiber that has five holes along its cladding. Proof-of-principle experiments with a diluted solution of fluorescently labeled particles are performed. The fiber probe presented here may find various applications in life-science and environmental monitoring. ©

  • 42.
    Fock, Jeppe
    et al.
    Technical University of Denmark, Denmark .
    Jonasson, Christian
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Johansson, Christer
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Hansen, Mikkel F.
    Technical University of Denmark, Denmark .
    Characterization of fine particles using optomagnetic measurements2017In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 19, no 13, p. 8802-8814Article in journal (Refereed)
    Abstract [en]

    The remanent magnetic moment and the hydrodynamic size are important parameters for the synthesis and applications of magnetic nanoparticles (MNPs). We present the theoretical basis for the determination of the remanent magnetic moment and the hydrodynamic size of MNPs with a narrow size distribution using optomagnetic measurements. In these, the 2nd harmonic variation of the intensity of light transmitted through an MNP suspension is measured as a function of an applied axial oscillating magnetic field. We first show how the measurements of the optomagnetic signal magnitude at a low frequency vs. magnetic field amplitude can be used to determine the MNP moment. Subsequently, we use linear response theory to describe the dynamic non-equilibrium response of the MNP suspension at low magnetic field amplitudes and derive a link between optomagnetic measurements and magnetic AC susceptibility measurements. We demonstrate the presented methodology on two samples of commercially available multi-core MNPs. The results compare well with those obtained by dynamic light scattering, AC susceptibility and vibrating sample magnetometry measurements on the same samples when the different weighting of the particle size in the techniques is taken into account. The optomagnetic technique is simple, fast and does not require prior knowledge of the concentration of MNPs and it thus has the potential to be used as a routine tool for quality control of MNPs.

  • 43.
    Fortes Brollo, Maria Eugenia
    et al.
    Institute of Material Science of Madrid (ICMM-CSIC), Spain.
    Hernández Flores, Patricia
    Centro Nacional de Biotecnología, (CNB-CSIC), Spain.
    Gutiérrez, Lucía
    Instituto Universitario de Nanociencia de Aragón (INA), Spain.
    Johansson, Christer
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Barber, Domingo Francisco
    Centro Nacional de Biotecnología, (CNB-CSIC), Spain.
    Morales, María Del Puerto
    Institute of Material Science of Madrid (ICMM-CSIC), Spain.
    Magnetic properties of nanoparticles as a function of their spatial distribution on liposomes and cells2018In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 20, no 26, p. 17829-17838Article in journal (Refereed)
    Abstract [en]

    The aggregation processes of magnetic nanoparticles in biosystems are analysed by comparing the magnetic properties of three systems with different spatial distributions of the nanoparticles. The first one is iron oxide nanoparticles (NPs) of 14 nm synthesized by coprecipitation with two coatings, (3-aminopropyl)trimethoxysilane (APS) and dimercaptosuccinic acid (DMSA). The second one is liposomes with encapsulated nanoparticles, which have different configurations depending on the NP coating (NPs attached to the liposome surface or encapsulated in its aqueous volume). The last system consists of two cell lines (Pan02 and Jurkat) incubated with the NPs. Dynamic magnetic behaviour (AC) was analysed in liquid samples, maintaining their colloidal properties, while quasi-static (DC) magnetic measurements were performed on lyophilised samples. AC measurements provide a direct method for determining the effect of the environment on the magnetization relaxation of nanoparticles. Thus, the imaginary (χ'') component shifts to lower frequencies as the aggregation state increases from free nanoparticles to those attached or embedded into liposomes in cell culture media and more pronounced when internalized by the cells. DC magnetization curves show no degradation of the NPs after interaction with biosystems in the analysed timescale. However, the blocking temperature is shifted to higher temperatures for the nanoparticles in contact with the cells, regardless of the location, the incubation time, the cell line and the nanoparticle coating, supporting AC susceptibility data. These results indicate that the simple fact of being in contact with the cells makes the nanoparticles aggregate in a non-controlled way, which is not the same kind of aggregation caused by the contact with the cell medium nor inside liposomes.

  • 44.
    Fougstedt, Christoffer
    et al.
    Chalmers University of Technology, Sweden.
    Sheikh, Alireza
    Chalmers University of Technology, Sweden.
    Johannisson, Pontus
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Larsson-Edefors, Per
    Chalmers University of Technology, Sweden.
    Filter Implementation for Power-Efficient Chromatic Dispersion Compensation2018In: IEEE Photonics Journal, ISSN 1097-5764, E-ISSN 1943-0655, Vol. 10, no 4, article id 7202919Article in journal (Refereed)
    Abstract [en]

    Chromatic dispersion (CD) compensation in coherent fiber-optic systems represents a very significant DSP block in terms of power dissipation. Since spectrally efficient coherent systems are expected to find a wider deployment in systems shorter than long haul, it becomes relevant to investigate filter implementation aspects of CD compensation in the context of systems with low-to-moderate amounts of accumulated dispersion. The investigation we perform in this paper has an emphasis on implementation aspects such as power dissipation and area usage, it deals with both time-domain and frequency-domain CD compensations, and it considers both A/D-conversion quantization and fixed-point filter design aspects. To enable an accurate analysis on power dissipation and chip area, the evaluated filters are implemented in a 28-nm fully depleted silicon-on-insulator (FD-SOI) process technology. We show that an optimization of the filter response that takes pulse shaping into account can significantly reduce power dissipation and area usage of time-domain implementations, making them a viable alternative to frequency-domain implementations.

  • 45.
    Franciscangelis, C.
    et al.
    Univ. Estadual de Campinas, Brazil.
    Margulis, Walter
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Floridia, C.
    CPqD, Brazil.
    Rosolem, J. B.
    CPqD, Brazil.
    Salgado, F. C.
    CPqD, Brazil.
    Nyman, T.
    Saab AB, Sweden.
    Petersson, M.
    Saab AB, Sweden.
    Hallander, P.
    Saab AB, Sweden.
    Hällstrom, S.
    KTH Royal Institute of Technology, Sweden.
    Söderquist, I.
    Saab AB, Sweden.
    Fruett, F.
    Univ. Estadual de Campinas, Brazil.
    Vibration measurement on composite material with embedded optical fiber based on phase-OTDR2017In: Proceedings of SPIE - The International Society for Optical Engineering Volume 10168, Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems 2017; 101683Q (2017), 2017, article id 101683QConference paper (Refereed)
    Abstract [en]

    Distributed sensors based on phase-optical time-domain reflectometry (phase-OTDR) are suitable for aircraft health monitoring due to electromagnetic interference immunity, small dimensions, low weight and flexibility. These features allow the fiber embedment into aircraft structures in a nearly non-intrusive way to measure vibrations along its length. The capability of measuring vibrations on avionics structures is of interest for what concerns the study of material fatigue or the occurrence of undesirable phenomena like flutter. In this work, we employed the phase-OTDR technique to measure vibrations ranging from some dozens of Hz to kHz in two layers of composite material board with embedded polyimide coating 0.24 numerical aperture single-mode optical fiber. © 2017 SPIE.

  • 46.
    Franciscangelis, Carolina
    et al.
    FEEC Unicamp, Brazil.
    Fruett, Fabiano
    FEEC Unicamp, Brazil.
    Margulis, Walter
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Kjellberg, Leif
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Floridia, Claudio
    CPqD, Brazil.
    Real-time multiple machines sound listening using a phase-OTDR based distributed microphone2017In: SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference, IMOC 2017, 2017Conference paper (Refereed)
    Abstract [en]

    We propose and experimentally demonstrate a spatially tunable phase-OTDR based distributed microphone for listening to the sound of multiple machines. The distributed acoustic sensing capability, allied with the real-time spatial tuning, enables listening to a drill and to a cooling water system pump placed in two different sections along a single optical fiber, one at a time. The recorded acoustic waveform profile of both machines agreed with their operating cycles. Moreover, the sounds generated by both engines are successfully distinguished with the proposed method even when both machines are operating simultaneously..

  • 47.
    Gao, Shang
    et al.
    Paul Scherrer Institut, Switzerland ; University of Geneva, Switzerland.
    Zaharko, Oksana
    Paul Scherrer Institut, Switzerland.
    Tsurkan, Vladimir
    University of Augsburg, Germany ; Institute of Applied Physics, Academy of Sciences of Moldova, Republic of Moldova.
    Prodan, Lilian
    Institute of Applied Physics, Academy of Sciences of Moldova, Republic of Moldova.
    Riordan, Edvard
    Cardiff University, UK.
    Lago, Jorge
    Universidad del Pa´ıs Vasco (UPV-EHU), Spain.
    Fak, Björn
    Institut Laue-Langevin, France.
    Wildes, Andrew R.
    Institut Laue-Langevin, France.
    Koza, Marek M.
    Institut Laue-Langevin, France.
    Ritter, Clemens
    Institut Laue-Langevin, France.
    Fouquet, Peter
    Institut Laue-Langevin, France.
    Keller, Lukas
    Paul Scherrer Institut, Switzerland.
    Canevet, Emmanuel
    Paul Scherrer Institut, Switzerland ; Technical University of Denmark, Denmark.
    Medarde, Marisa
    Paul Scherrer Institut, Switzerland.
    Blomgren, Jakob
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Johansson, Christer
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Giblin, Sean R.
    Cardiff University, UK.
    Vrtnik, Stanislav
    Jozef Stefan Institute, Slovenia.
    Luzar, Jose
    Jozef Stefan Institute, Slovenia.
    Loidl, Alois
    University of Augsburg, Germany.
    Ruegg, Christina
    Paul Scherrer Institut, Switzerland ; University of Geneva, Switzerland.
    Fennell, Tom
    Paul Scherrer Institut, Switzerland.
    Dipolar Spin Ice States with a Fast Monopole Hopping Rate in CdEr2X4 (X = Se, S)2018In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 120, no 13Article in journal (Refereed)
    Abstract [en]

    Excitations in a spin ice behave as magnetic monopoles, and their population and mobility control the dynamics of a spin ice at low temperature. CdEr2Se4 is reported to have the Pauling entropy characteristic of a spin ice, but its dynamics are three orders of magnitude faster than the canonical spin ice Dy2Ti2O7. In this Letter we use diffuse neutron scattering to show that both CdEr2Se4 and CdEr2S4 support a dipolar spin ice state-the host phase for a Coulomb gas of emergent magnetic monopoles. These Coulomb gases have similar parameters to those in Dy2Ti2O7, i.e., dilute and uncorrelated, and so cannot provide three orders faster dynamics through a larger monopole population alone. We investigate the monopole dynamics using ac susceptometry and neutron spin echo spectroscopy, and verify the crystal electric field Hamiltonian of the Er3+ ions using inelastic neutron scattering. A quantitative calculation of the monopole hopping rate using our Coulomb gas and crystal electric field parameters shows that the fast dynamics in CdEr2X4 (X = Se, S) are primarily due to much faster monopole hopping. Our work suggests that CdEr2X4 offer the possibility to study alternative spin ice ground states and dynamics, with equilibration possible at much lower temperatures than the rare earth pyrochlore examples.

  • 48.
    Gavilán, Helena
    et al.
    ICMM/CSIC, Spain.
    Kowalski, Anja
    Micromod Partikeltechnologie GmbH, Germany.
    Heinke, David
    NanoPET Pharma GmbH, Germany.
    Sugunan, Abhilash
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Sommertune, Jens
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Varón, Miriam
    Technical University of Denmark, Denmark.
    Bogart, Lara K.
    University College of London, UK.
    Posth, Oliver
    Physikalisch-Technische Bundesanstalt, Germany.
    Zeng, Lunjie
    Chalmers University of Technology, Gothenburg, Sweden.
    González-Alonso, David
    University of Cantabria, Spain.
    Balceris, Chrsitoph
    Institute of Electrical Measurement and Fundamental Electrical Engineering, Germany.
    Fock, Jeppe
    Technical University of Denmark, Denmark.
    Wetterskog, Erik
    Uppsala University, Sweden.
    Frandsen, Cathrine
    Technical University of Denmark, Denmark.
    Gehrke, Nicole
    NanoPET Pharma GmbH, Germany.
    Grüttner, Cordula
    Micromod Partikeltechnologie GmbH, Germany.
    Fornara, Andrea
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Ludwig, Frank
    Institute of Electrical Measurement and Fundamental Electrical Engineerig, Germany.
    Veintemillas-Verdaguer, Sabino
    Instituto de Ciencia de Materiales de Madrid, ICMM/CSIC, Madrid, Spain.
    Johansson, Christer
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Morales, M. Puerto
    ICMM/CSIC, Madrid, Spain.
    Colloidal Flower-Shaped Iron Oxide Nanoparticles: Synthesis Strategies and Coatings2017In: Particle & particle systems characterization, ISSN 0934-0866, E-ISSN 1521-4117, Vol. 34, no 7, article id 1700094Article in journal (Refereed)
    Abstract [en]

    The assembly of magnetic cores into regular structures may notably influence the properties displayed by a magnetic colloid. Here, key synthesis parameters driving the self-assembly process capable of organizing colloidal magnetic cores into highly regular and reproducible multi-core nanoparticles are determined. In addition, a self-consistent picture that explains the collective magnetic properties exhibited by these complex assemblies is achieved through structural, colloidal, and magnetic means. For this purpose, different strategies to obtain flower-shaped iron oxide assemblies in the size range 25–100 nm are examined. The routes are based on the partial oxidation of Fe(OH)2, polyol-mediated synthesis or the reduction of iron acetylacetonate. The nanoparticles are functionalized either with dextran, citric acid, or alternatively embedded in polystyrene and their long-term stability is assessed. The core size is measured, calculated, and modeled using both structural and magnetic means, while the Debye model and multi-core extended model are used to study interparticle interactions. This is the first step toward standardized protocols of synthesis and characterization of flower-shaped nanoparticles.

  • 49.
    Golabi, Mohsen
    et al.
    Linköping University, Sweden.
    Kuralay, Filiz
    Ordu University, Turkey.
    Jager, Edwin W. H.
    Linköping University, Sweden.
    Beni, Valerio
    RISE - Research Institutes of Sweden, ICT, Acreo. Linköping University, Sweden.
    Turner, Anthony P. F.
    Linköping University, Sweden.
    Electrochemical bacterial detection using poly(3-aminophenylboronic acid)-based imprinted polymer2017In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 93, p. 87-93Article in journal (Refereed)
    Abstract [en]

    Biosensors can deliver the rapid bacterial detection that is needed in many fields including food safety, clinical diagnostics, biosafety and biosecurity. Whole-cell imprinted polymers have the potential to be applied as recognition elements in biosensors for selective bacterial detection. In this paper, we report on the use of 3-aminophenylboronic acid (3-APBA) for the electrochemical fabrication of a cell-imprinted polymer (CIP). The use of a monomer bearing a boronic acid group, with its ability to specifically interact with cis-diol, allowed the formation of a polymeric network presenting both morphological and chemical recognition abilities. A particularly beneficial feature of the proposed approach is the reversibility of the cis-diol-boronic group complex, which facilitates easy release of the captured bacterial cells and subsequent regeneration of the CIP. Staphylococcus epidermidis was used as the model target bacteria for the CIP and electrochemical impedance spectroscopy (EIS) was explored for the label-free detection of the target bacteria. The modified electrodes showed a linear response over the range of 103–107 cfu/mL. A selectivity study also showed that the CIP could discriminate its target from non-target bacteria having similar shape. The CIPs had high affinity and specificity for bacterial detection and provided a switchable interface for easy removal of bacterial cell.

  • 50.
    Hammarling, Krister
    et al.
    Mid Sweden University, Sweden.
    Engholm, Magnus
    Mid Sweden University, Sweden.
    Andersson, Henrik
    Mid Sweden University, Sweden.
    Sandberg, Mats
    RISE - Research Institutes of Sweden, ICT, Acreo. Mid Sweden University, Sweden.
    Nilsson, Hans Erik
    Mid Sweden University, Sweden.
    Broad-range hydrogel-based pH sensor with capacitive readout manufactured on a flexible substrate2018In: Chemosensors, ISSN 2227-9040, Vol. 6, no 3, article id 30Article in journal (Refereed)
    Abstract [en]

    Environmental monitoring of land, water and air, is an area receiving greater attention because of human health and safety concerns. Monitoring the type of pollution and concentration levels is vital, so that appropriate contingency plans can be determined. To effectively monitor the environment, there is a need for new sensors and sensor systems that suits these type of measurements. However, the diversity of sensors suitable for low, battery powered- and large area sensor systems are limited. We have manufactured and characterized a flexible pH sensor using laser processing and blade coating techniques that is able to measure pH between 2.94 and 11.80. The sensor consists of an interdigital capacitance with a pH sensitive hydrogel coating. Thin sensors can reach 95% of their final value value within 3 min, and are stable after 4 min. Good repeatability was achieved in regard to cycling of the sensor with different pH and multiple measurements from dry state. We have also studied the relation between an interdigital capacitance penetration depth and hydrogels expansion. We believe that our passive sensor is suitable to be used in low power and large area sensor networks.

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