miun.sePublications
Change search
Refine search result
1234567 1 - 50 of 322
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the 'Create feeds' function.
  • 1.
    Ahmad, Naeem
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Modelling, optimization and design of visual sensor networks for sky surveillance2013Doctoral thesis, comprehensive summary (Other academic)
  • 2.
    Ahmad, Naeem
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Imran, Muhammad
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Khursheed, Khursheed
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Lawal, Najeem
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    O'Nils, Mattias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Model, placement optimization and verification of a sky surveillance visual sensor network2013In: International Journal of Space-Based and Situated Computing (IJSSC), ISSN 2044-4893, E-ISSN 2044-4907, Vol. 3, no 3, 125-135 p.Article in journal (Refereed)
    Abstract [en]

    A visual sensor network (VSN) is a distributed system of a large number of camera nodes, which generates two dimensional data. This paper presents a model of a VSN to track large birds, such as golden eagle, in the sky. The model optimises the placement of camera nodes in VSN. A camera node is modelled as a function of lens focal length and camera sensor. The VSN provides full coverage between two altitude limits. The model can be used to minimise the number of sensor nodes for any given camera sensor, by exploring the focal lengths that fulfils both the full coverage and minimum object size requirement. For the case of large bird surveillance, 100% coverage is achieved for relevant altitudes using 20 camera nodes per km² for the investigated camera sensors. A real VSN is designed and measurements of VSN parameters are performed. The results obtained verify the VSN model.

  • 3.
    Ahmad, Naeem
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Imran, Muhammad
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Khursheed, Khursheed
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Lawal, Najeem
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    O'Nils, Mattias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Solution space exploration of volumetric surveillance using a general taxonomy2013In: Proceedings of SPIE - The International Society for Optical Engineering / [ed] Daniel J. Henry, 2013, Art. no. 871317- p.Conference paper (Refereed)
    Abstract [en]

    Visual surveillance systems provide real time monitoring of the events or the environment. The availability of low cost sensors and processors has increased the number of possible applications of these kinds of systems. However, designing an optimized visual surveillance system for a given application is a challenging task, which often becomes a unique design task for each system. Moreover, the choice of components for a given surveillance application out of a wide spectrum of available alternatives is not an easy job. In this paper, we propose to use a general surveillance taxonomy as a base to structure the analysis and development of surveillance systems. We demonstrate the proposed taxonomy for designing a volumetric surveillance system for monitoring the movement of eagles in wind parks aiming to avoid their collision with wind mills. The analysis of the problem is performed based on taxonomy and behavioral and implementation models are identified to formulate the solution space for the problem. Moreover, we show that there is a need for generalized volumetric optimization methods for camera deployment.

  • 4.
    Ahmad, Naeem
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Khursheed, Khursheed
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Imran, Muhammad
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Lawal, Najeem
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    O'Nils, Mattias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Modeling and Verification of a Heterogeneous Sky Surveillance Visual Sensor Network2013In: International Journal of Distributed Sensor Networks, ISSN 1550-1329, E-ISSN 1550-1477, Art. id. 490489- p.Article in journal (Refereed)
    Abstract [en]

    A visual sensor network (VSN) is a distributed system of a large number of camera nodes and has useful applications in many areas. The primary difference between a VSN and an ordinary scalar sensor network is the nature and volume of the information. In contrast to scalar sensor networks, a VSN generates two-dimensional data in the form of images. In this paper, we design a heterogeneous VSN to reduce the implementation cost required for the surveillance of a given area between two altitude limits. The VSN is designed by combining three sub-VSNs, which results in a heterogeneous VSN. Measurements are performed to verify full coverage and minimum achieved object image resolution at the lower and higher altitudes, respectively, for each sub-VSN. Verification of the sub-VSNs also verifies the full coverage of the heterogeneous VSN, between the given altitudes limits. Results show that the heterogeneous VSN is very effective to decrease the implementation cost required for the coverage of a given area. More than 70% decrease in cost is achieved by using a heterogeneous VSN to cover a given area, in comparison to homogeneous VSN. © 2013 Naeem Ahmad et al.

  • 5.
    Ahmad, Naeem
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    O'Nils, Mattias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Lawal, Najeem
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    A taxonomy of visual surveillance systems2013Report (Other academic)
    Abstract [en]

    The increased security risk in society and the availability of low cost sensors and processors has expedited the research in surveillance systems. Visual surveillance systems provide real time monitoring of the environment. Designing an optimized surveillance system for a given application is a challenging task. Moreover, the choice of components for a given surveillance application out of a wide spectrum of available products is not an easy job.

     

    In this report, we formulate a taxonomy to ease the design and classification of surveillance systems by combining their main features. The taxonomy is based on three main models: behavioral model, implementation model, and actuation model. The behavioral model helps to understand the behavior of a surveillance problem. The model is a set of functions such as detection, positioning, identification, tracking, and content handling. The behavioral model can be used to pinpoint the functions which are necessary for a particular situation. The implementation model structures the decisions which are necessary to implement the surveillance functions, recognized by the behavioral model. It is a set of constructs such as sensor type, node connectivity and node fixture. The actuation model is responsible for taking precautionary measures when a surveillance system detects some abnormal situation.

     

    A number of surveillance systems are investigated and analyzed on the basis of developed taxonomy. The taxonomy is general enough to handle a vast range of surveillance systems. It has organized the core features of surveillance systems at one place. It may be considered an important tool when designing surveillance systems. The designers can use this tool to design surveillance systems with reduced effort, cost, and time.

  • 6.
    Ahmad, Nisar
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Design and Implementation of a High Frequency Flyback Converter2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The power supply designers choose flyback topology due to its promising features of design simplicity, cost effectiveness and multiple outputs handling capability. The designed product based on flyback topology should be smaller in size, cost effective and energy efficient. Similarly, designers focus on reducing the circuit losses while operating at high frequencies that affect the converter efficiency and performance. Based on the above circumstances, an energy efficient open loop high frequency flyback converter is designed and operated in MHz frequency region using step down multilayer PCB planar transformer. The maximum efficiency of 84.75% is observed and maximum output power level reached is 22.8W. To overcome the switching losses, quasi-resonant soft switching technique is adopted and a high voltage CoolMOS power transistor is used.

  • 7.
    Alam, Mohammad Anzar
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Online optical method for real-time surface measurement using line-of-light triangulation2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Real time paper surface-web measurement is one of the challenging research fields. The traditional laboratory method has many limitations and is unable to measure the entire tambour during the manufacturing process. It has been necessary to develop an online technique that could measure the surface topography in real time. An optical technique was developed, based on laser triangulation, and is applied to develop a new prototype device, which characterizes high speed paper-web surfaces over a wide scale of spatial wavelengths spectrum and computes the surface roughness in real time. The used multi channel pulsed laser diode, source of illumination onto the paper-web, is of benefit due to its low coherence length and is capable to deliver a powerful burst of light beam over a 1 µs duration, which delivers energy of 100 µJ per pulse. The short exposure time avoids blurriness in the acquired images which could possible due to the high speed and vibrations on the paper-web.

    The laser beam is shaped into a narrow line-of-light using cylindrical lenses and is projected onto a paper-web surface, which covers a physical length of about 210 mm. The created line-of-light cross section full width at half maximum, FWHM Gaussian distribution, is 2-3 pixels on the image. The line-of-light is projected onto the paper-web perpendicular to the plane of the surface. The low angled, low specular, reduced coherence length, scattered reflected laser line is captured by the 3 CCD sensors, which are synchronized with the laser source. The low specular light ensures to avoid saturation of the imaging sensors if the surface is very smooth, and obliquely captures the z-directional fine feature of the surface.

    The scattered phenomenon of the reflected light is responsible for the surface irregularity measurements. The basic image processing algorithm is applied in order to remove noise and cropped the images widthwise so that only pixels above a preset threshold gray level can be processed, which enables efficient real time measurement. The image is transformed into a 1D array using the center of gravity, COG. The accuracy and precision of the COG depends on the line-of-light FWHM, which, in turn, is responsible for the accuracy, noise and the resolution of the developed technique. The image subpixel resolution achieved is 0.01 times a pixel and uuncertainty in the raw data is 0.43 µm while it is 0.05 µm in the rms roughness.

    The signal processing steps combining the B-Spline filter and the filter in the spatial frequency domain were employed in order to separate roughness, waviness, and form and position error in the raw profile. The prototype is designed to measure online surface roughness and to characterize surface in a spatial wavelength spectrum from 0.09 to 30 mm, which is extendable to any required spatial range in order to cover a wide scale surface feature such as micro roughness, macro roughness and waviness. It is proven that exploitation of a simple laser triangulation technique could lead to an improvement in the overall quality and efficiency in the paper and paperboard industries and it can also be of potential interest for the other surface characterization problems.

  • 8.
    Alam, Mohammad Anzar
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    O'Nils, Mattias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Manuilskiy, Anatoliy
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Thim, Jan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Real time surface measurement technique in a wide range of wavelengths spectrum2014In: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 14, no 1, 285-294 p.Article in journal (Refereed)
    Abstract [en]

    Real time surface topography measurement in the paper and paperboard industries is a challenging research field. The existing online techniques measure only a small area of paper surface and estimate topographical irregularities in a narrow scale as a single predictor. Considering the limitations and complications in measuring the surface at high speed, a laser line triangulation technique is explored to measure surface topography in a wide scale. The developed technique is new for the paper and paperboard application that scans a line onto the paper-web surface up to 210 mm in length in the cross machine direction. The combination of a narrow laser linewidth imaging, a subpixel resolution, and the selection of a unique measurement location has made it possible to measure roughness and simultaneously characterize paper surface topography from 0.1 to 30 mm spatial wavelength. This spatial range covers wide scale surface properties such as roughness, cockling, and waviness. The technique clearly distinguishes and characterizes the surface of newspaper, and lightweight coated, coated, and uncoated paperboard in real time during the paper manufacturing process. The system temporal noise for the average roughness is estimated as 37 dB. The signal to noise ratio found is from 5.4 to 8.1 in the short spatial wavelength up to 1 mm, whereas it is more than 75 in the long spatial wavelength from 5 to 10 mm.

  • 9.
    Alam, Mohammad Anzar
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    O'Nils, Mattias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Manuilskiy, Anatoliy
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Thim, Jan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Westerlind, Christina
    Performance and Prototyping Laboratory, SCA AB, Research and Development Centre, Sundsvall 852 37, Sweden .
    Limitation of a line-of-light online paper surface measurement system2014In: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 14, no 8, 2715-2724 p.Article in journal (Refereed)
    Abstract [en]

    A new prototype device has been developed based on a laser triangulation principle to measure online surface topography in the paper and paperboard industries. It characterizes the surface in a wide spatial scale of topography from 0.09-10 mm. The prototype's technique projects a narrow line-of-light perpendicularly onto the moving paper-Web surface and scattered reflected light is collected at a low angle, low specular, and reduced coherent length onto the CCD sensors synchronized with the laser sources. The scattering phenomenon determines surface deviations in the z-direction. The full-width, at half-maximum of a laser line in cross section is sensitive in computation of the surface topography. The signal processing aspect of the image processing, for example, threshold and filtering algorithms are also sensitive in estimating the accurate surface features. Moreover, improper light illumination, intensity, reflection, occlusion, surface motion, and noise in the imaging sensor, and so forth, all contribute to deteriorate the measurements. Optical techniques measure the surface indirectly and, in general, an evaluation of the performance and the limitations of the technique are both essential and challenging. The paper describes the accuracy, uncertainty, and limitations of the developed technique in the raw profiles and in terms of the rms roughness. The achieved image subpixel resolution is 0.01 times a pixel. Statistically estimated uncertainty (2σ) in the laboratory environment was found 0.05 μm for a smooth sample, which provides a 95% confidence level in the rms roughness results. The depth of field of the prototype is ~2.4 mm.

  • 10.
    Albani, Giorgia
    et al.
    Dipartimento di Fisica, Universitá degli Studi di Milano-Bicocca, Piazza della Scienza 3, Milano, Italy; INFN Sezione di Milano-Bicocca, Piazza della Scienza 3, Milano, Italy.
    Perelli Cippo, Enrico
    Istituto di Fisica Del Plasma (IFP-CNR), Via Cozzi 53, Milano, Italy.
    Croci, Gabriele
    Dipartimento di Fisica, Universitá degli Studi di Milano-Bicocca, Piazza della Scienza 3, Milano, Italy; INFN Sezione di Milano-Bicocca, Piazza della Scienza 3, Milano, Italy.
    Muraro, Andrea
    Istituto di Fisica Del Plasma (IFP-CNR), Via Cozzi 53, Milano, Italy.
    Schooneveld, Erik
    STFC-ISIS Facility, RAL, Didcot, United Kingdom.
    Scherillo, Antonella
    STFC-ISIS Facility, RAL, Didcot, United Kingdom.
    Hall-Wilton, Richard J.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design. European Spallation Source ERIC, Lund.
    Kanaki, Kalliopi
    European Spallation Source ERIC, Lund.
    Höglund, Carina
    European Spallation Source ERIC, Lund; Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping.
    Hultman, Lars
    Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping.
    Birch, Jens
    Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping.
    Claps, Gerardo
    INFN, Laboratori Nazionali di Frascati, Via Fermi 40, Frascati, Italy.
    Murtas, Fabrizio
    INFN, Laboratori Nazionali di Frascati, Via Fermi 40, Frascati, Italy.
    Rebai, Marica
    Dipartimento di Fisica, Universitá degli Studi di Milano-Bicocca, Piazza della Scienza 3, Milano, Italy; INFN Sezione di Milano-Bicocca, Piazza della Scienza 3, Milano, Italy.
    Tardocchi, Marco
    Istituto di Fisica Del Plasma (IFP-CNR), Via Cozzi 53, Milano, Italy.
    Gorini, Giuseppe
    Dipartimento di Fisica, Universitá degli Studi di Milano-Bicocca, Piazza della Scienza 3, Milano, Italy; INFN Sezione di Milano-Bicocca, Piazza della Scienza 3, Milano, Italy; Istituto di Fisica Del Plasma (IFP-CNR), Via Cozzi 53, Milano, Italy.
    Evolution in boron-based GEM detectors for diffraction measurements: From planar to 3D converters2016In: Measurement science and technology, ISSN 0957-0233, E-ISSN 1361-6501, Vol. 27, no 11, 115902Article in journal (Refereed)
    Abstract [en]

    The so-called '3He-crisis' has motivated the neutron detector community to undertake an intense R&D programme in order to develop technologies alternative to standard 3He tubes and suitable for neutron detection systems in future spallation sources such as the European spallation source (ESS). Boron-based GEM (gas electron multiplier) detectors are a promising '3He-free' technology for thermal neutron detection in neutron scattering experiments. In this paper the evolution of boron-based GEM detectors from planar to 3D converters with an application in diffraction measurements is presented. The use of 3D converters coupled with GEMs allows for an optimization of the detector performances. Three different detectors were used for diffraction measurements on the INES instrument at the ISIS spallation source. The performances of the GEM-detectors are compared with those of conventional 3He tubes installed on the INES instrument. The conceptual detector with the 3D converter used in this paper reached a count rate per unit area of about 25% relative to the currently installed 3He tube. Its timing resolution is similar and the signal-to-background ratio (S/B) is 2 times lower.

  • 11.
    Allahgholi, A.
    et al.
    DESY, D-22607 Hamburg, Germany.
    Becker, J.
    DESY, D-22607 Hamburg, Germany.
    Bianco, L.
    DESY, D-22607 Hamburg, Germany.
    Bradford, R.
    Adv Photon Source, Chicago, IL USA.
    Delfs, A.
    DESY, D-22607 Hamburg, Germany.
    Dinapoli, R.
    Paul Scherrer Inst, OFLB-006, CH-5232 Villigen, Switzerland.
    Goettlicher, P.
    DESY, D-22607 Hamburg, Germany.
    Gronewald, M.
    Univ Bonn, D-53115 Bonn, Germany.
    Graafsma, Heinz
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design. DESY, D-22607 Hamburg, Germany.
    Greiffenberg, D.
    Paul Scherrer Inst, OFLB-006, CH-5232 Villigen, Switzerland.
    Henrich, B. H.
    Paul Scherrer Inst, OFLB-006, CH-5232 Villigen, Switzerland.
    Hirsemann, H.
    DESY, D-22607 Hamburg, Germany.
    Jack, S.
    DESY, D-22607 Hamburg, Germany.
    Klanner, R.
    Univ Hamburg, D-22761 Hamburg, Germany.
    Klyuev, A.
    DESY, D-22607 Hamburg, Germany.
    Krueger, H.
    Univ Bonn, D-53115 Bonn, Germany.
    Lange, S.
    DESY, D-22607 Hamburg, Germany.
    Marras, A.
    DESY, D-22607 Hamburg, Germany.
    Mezza, D.
    Paul Scherrer Inst, OFLB-006, CH-5232 Villigen, Switzerland.
    Mozzanica, A.
    Paul Scherrer Inst, OFLB-006, CH-5232 Villigen, Switzerland.
    Perova, I.
    DESY, D-22607 Hamburg, Germany.
    Xia, Q.
    DESY, D-22607 Hamburg, Germany.
    Schmitt, B.
    Paul Scherrer Inst, OFLB-006, CH-5232 Villigen, Switzerland.
    Schwandt, J.
    Univ Hamburg, D-22761 Hamburg, Germany.
    Sheviakov, I.
    DESY, D-22607 Hamburg, Germany.
    Shi, X.
    Paul Scherrer Inst, OFLB-006, CH-5232 Villigen, Switzerland.
    Trunk, U.
    DESY, D-22607 Hamburg, Germany.
    Zhang, J.
    DESY, D-22607 Hamburg, Germany.
    The adaptive gain integrating pixel detector2016In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 11, no 2, C02066Article in journal (Refereed)
    Abstract [en]

    The adaptive gain integrating pixel detector (AGIPD) is a development of a collaboration between Deustsches Elektronen-Synchrotron (DESY), the Paul-Scherrer-Institute (PSI), the University of Hamburg and the University of Bonn. The detector is designed to cope with the demanding challenges of the European XFEL. Therefore it comes along with an adaptive gain stage allowing a high dynamic range, spanning from single photon sensitivity to 10(4) x 12.4 keV photons and 352 analogue memory cells per pixel. The aim of this report is to briefly explain the concepts of the AGIPD electronics and mechanics and then present recent experiments demonstrating the functionality of its key features.

  • 12.
    Allahgholi, A.
    et al.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Becker, J.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany; Cornell University, Ithaca, NY, United States .
    Bianco, L.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Delfs, A.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Arino-Estrada, G.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Gottlicher, P.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Graafsma, Heinz
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design. Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Hirsemann, H.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Jack, S.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Klyuev, A.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Lange, S.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Marras, A.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Poehlsen, J.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Sheviakov, I.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Trunk, U.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Xia, Q.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Zhang, J.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Zimmer, M.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany.
    Dinapoli, R.
    PSI, Villigen, Switzerland.
    Greiffenberg, D.
    PSI, Villigen, Switzerland.
    Mezza, D.
    PSI, Villigen, Switzerland.
    Mozzanica, A.
    PSI, Villigen, Switzerland.
    Schmitt, B.
    PSI, Villigen, Switzerland.
    Shi, X.
    PSI, Villigen, Switzerland.
    Klanner, R.
    University of Hamburg, Germany.
    Schwandt, J.
    University of Hamburg, Germany.
    Kruger, H.
    University of Bonn, Germany.
    Rah, S.
    Pohang Accelerator Laboratory, Pohang, South Korea.
    The AGIPD 1.0 ASIC: Random access high frame rate, high dynamic range X-ray camera readout for the European XFEL2015In: 2015 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2015, Institute of Electrical and Electronics Engineers (IEEE), 2015, 7581819Conference paper (Refereed)
    Abstract [en]

    The European XFEL is an extremely brilliant Free Electron Laser Source with a very demanding pulse structure: trains of 2700 X-Ray pulses are repeated at 10 Hz. The pulses inside the train are spaced by 220 ns and each one contains up to 1012 photons of 12.4 keV, while being ≤ 100 fs in length. AGIPD (Adaptive Gain Integrating Pixel Detector) is a hybrid 1M-pixel detector developed by DESY, PSI, and the Universities of Bonn and Hamburg to cope with these properties. Thus the readout ASIC has to provide not only single photon sensitivity and a dynamic range ≳ 104 photons/pixel in the same image but also a memory for as many images of a pulse train as possible for delayed readout prior to the next train. The AGIPD 1.0 ASIC uses a 130 nm CMOS technology and radiation tolerant techniques to withstand the radiation damage incurred by the high impinging photon flux. Each ASIC contains 64 × 64 pixels of 200μmχ200μm. The circuit of each pixel contains a charge sensitive preamplifier with threefold switchable gain, a discriminator for an adaptive gain selection, and a correlated double sampling (CDS) stage to remove reset and low-frequency noise components. The output of the CDS, as well as the dynamically selected gain is sampled in a capacitor-based analogue memory for 352 samples, which occupies about 80% of a pixels area. For readout each pixel features a charge sensitive buffer. A control circuit with a command based interface provides random access to the memory and controls the row-wise readout of the data via multiplexers to four differential analogue ports. The AGIPD 1.0 full scale ASIC has been received back from the foundry in fall of 2013. Since then it has been extensively characterised also with a sensor as a single chip and in 2 × 8-chip modules for the AGIPD 1 Mpix detector. We present the design of the AGIPD 1.0 ASIC along with supporting results, also from beam tests at PETRA III and APS, and show changes incorporated in the recently taped out AGIPD 1.1 ASIC upgrade.

  • 13.
    Allahgholi, A.
    et al.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Becker, J.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Bianco, L.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Delfs, A.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Dinapoli, R.
    Paul Scherrer Inst, CH-5232 Villigen, Switzerland.
    Arino-Estrada, G.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Goettlicher, P.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Graafsma, Heinz
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design. Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Greiffenberg, D.
    Paul Scherrer Inst, CH-5232 Villigen, Switzerland.
    Hirsemann, H.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Jack, S.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Klanner, R.
    Univ Hamburg, Mittelweg 177, D-20148 Hamburg, Germany.
    Klyuev, A.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Krueger, H.
    Univ Bonn, D-53012 Bonn, Germany.
    Lange, S.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Marras, A.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Mezza, D.
    Paul Scherrer Inst, CH-5232 Villigen, Switzerland.
    Mozzanica, A.
    Paul Scherrer Inst, CH-5232 Villigen, Switzerland.
    Poehlsen, J.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Rah, S.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Xia, Q.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Schmitt, B.
    Paul Scherrer Inst, CH-5232 Villigen, Switzerland.
    Schwandt, J.
    Univ Hamburg, Mittelweg 177, D-20148 Hamburg, Germany.
    Sheviakov, I.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Shi, X.
    Paul Scherrer Inst, CH-5232 Villigen, Switzerland.
    Smoljanin, S.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Trunk, U.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Zhang, J.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Zimmer, M.
    Deutsch Elekt Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Front end ASIC for AGIPD, a high dynamic range fast detector for the European XFEL2016In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 11, no 1, C01057Article in journal (Refereed)
    Abstract [en]

    The Adaptive Gain Integrating Pixel Detector (AGIPD) is a hybrid pixel X-ray detector for the European-XFEL. One of the detector's important parts is the radiation tolerant front end ASIC fulfilling the European-XFEL requirements: high dynamic range-from sensitivity to single 12.5keV-photons up to 104 photons. It is implemented using the dynamic gain switching technique with three possible gains of the charge sensitive preamplifier. Each pixel can store up to 352 images in memory operated in random-access mode at >= 4.5MHz frame rate. An external vetoing may be applied to overwrite unwanted frames.

  • 14.
    Allahgholi, A.
    et al.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Becker, J.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Bianco, L.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Delfs, A.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Gottlicher, P.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Graafsma, Heinz
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design. Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Hirsemann, H.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Jack, S.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Klyuev, A.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Lange, S.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Marras, A.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Sheviakov, I.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Trunk, U.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Xia, Q.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Zhang, J.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Zimmer, M.
    Center for Free-Electron Laser Science, DESY, Hamburg, Germany .
    Dinapoli, R.
    PSI, Villigen, Switzerland .
    Greiffenberg, D.
    PSI, Villigen, Switzerland .
    Mezza, D.
    PSI, Villigen, Switzerland .
    Mozzanica, A.
    PSI, Villigen, Switzerland .
    Schmitt, B.
    PSI, Villigen, Switzerland .
    Shi, X.
    PSI, Villigen, Switzerland .
    Klanner, R.
    University of Hamburg, Germany .
    Schwandt, J.
    University of Hamburg, Germany .
    Gronewald, M.
    University of Bonn, Germany .
    Kruger, H.
    University of Bonn, Germany .
    Rah, S.
    Pohang Accelerator Laboratory, Pohang, South Korea .
    AGIPD 1.0: The high-speed high dynamic range readout ASIC for the adaptive gain integrating pixel detector at the European XFEL2016In: 2014 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS/MIC 2014, Institute of Electrical and Electronics Engineers (IEEE), 2016, 7431038Conference paper (Refereed)
    Abstract [en]

    AGIPD is a hybrid pixel X-ray detector developed by a collaboration between Deutsches Elektronen-Synchrotron (DESY), Paul-Scherrer-Institute (PSI), University of Hamburg and the University of Bonn. The detector is designed to comply with the requirements of the European XFEL. The radiation tolerant Application Specific Integrated Circuit (ASIC) is designed with the following highlights: high dynamic range, spanning from single photon sensitivity up to 104 × 12.4 keV photons, achieved by the use of dynamic gain switching, auto-selecting one of 3 gains of the charge sensitive pre-amplifier. To cope with the unique features of the European XFEL source, image data is stored in 352 analogue memory cells per pixel. The selected gain is stored in the same way and depth, encoded as one of 3 voltage levels. These memories are operated in random-access mode at 4.5MHz frame rate. Data is read out on a row-by-row basis via multiplexers to the DAQ system for digitisation during the 99.4ms gap between the bunch trains of the European XFEL. The AGIPD 1.0 ASIC features 64×64 pixels with a pixel area of 200×200 μm2. It is bump-bonded to a 500 μm thick silicon sensor. The principles of the chip architecture were proven in different experiments and the ASIC characterization was performed with a series of development prototypes. The mechanical concept of the detector system was developed in close contact with the XFEL beamline scientists to ensure a seamless integration into the beamline setup and is currently being manufactured. The first single module system was successfully tested at APS1 the high dynamic range allows imaging of the direct synchrotron beam along with single photon sensitivity and burst imaging of 352 subsequent frames synchronized to the source.

  • 15.
    Ambatipudi, Radhika
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    High Frequency (MHz) Planar Transformers for Next Generation Switch Mode Power Supplies2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Increasing the power density of power electronic converters while reducing or maintaining the same cost, offers a higher potential to meet the current trend inrelation to various power electronic applications. High power density converters can be achieved by increasing the switching frequency, due to which the bulkiest parts, such as transformer, inductors and the capacitor's size in the convertercircuit can be drastically reduced. In this regard, highly integrated planar magnetics are considered as an effective approach compared to the conventional wire wound transformers in modern switch mode power supplies (SMPS). However, as the operating frequency of the transformers increase from several hundred kHz to MHz, numerous problems arise such as skin and proximity effects due to the induced eddy currents in the windings, leakage inductance and unbalanced magnetic flux distribution. In addition to this, the core losses whichare functional dependent on frequency gets elevated as the operating frequency increases. Therefore, this thesis provides an insight towards the problems related to the high frequency magnetics and proposes a solution with regards to different aspects in relation to designing high power density, energy efficient transformers.The first part of the thesis concentrates on the investigation of high power density and highly energy efficient coreless printed circuit board (PCB) step-down transformers useful for stringent height DC-DC converter applications, where the core losses are being completely eliminated. These transformers also maintain the advantages offered by existing core based transformers such as, high coupling coefficient, sufficient input impedance, high energy efficiency and wide frequencyband width with the assistance of a resonant technique. In this regard, several coreless PCB step down transformers of different turn’s ratio for power transfer applications have been designed and evaluated. The designed multilayered coreless PCB transformers for telecom and PoE applications of 8,15 and 30W show that the volume reduction of approximately 40 - 90% is possible when compared to its existing core based counterparts while maintaining the energy efficiency of the transformers in the range of 90 - 97%. The estimation of EMI emissions from the designed transformers for the given power transfer application proves that the amount of radiated EMI from a multilayered transformer is lessthan that of the two layered transformer because of the decreased radius for thesame amount of inductance.The design guidelines for the multilayered coreless PCB step-down transformer for the given power transfer application has been proposed. The designed transformer of 10mm radius has been characterized up to the power level of 50Wand possesses a record power density of 107W/cm3 with a peak energy efficiency of 96%. In addition to this, the design guidelines of the signal transformer fordriving the high side MOSFET in double ended converter topologies have been proposed. The measured power consumption of the high side gate drive circuitvitogether with the designed signal transformer is 0.37W. Both these signal andpower transformers have been successfully implemented in a resonant converter topology in the switching frequency range of 2.4 – 2.75MHz for the maximum load power of 34.5W resulting in the peak energy efficiency of converter as 86.5%.This thesis also investigates the indirect effect of the dielectric laminate on the magnetic field intensity and current density distribution in the planar power transformers with the assistance of finite element analysis (FEA). The significanceof the high frequency dielectric laminate compared to FR-4 laminate in terms of energy efficiency of planar power transformers in MHz frequency region is also explored.The investigations were also conducted on different winding strategies such as conventional solid winding and the parallel winding strategies, which play an important role in the design and development of a high frequency transformer and suggested a better choice in the case of transformers operating in the MHz frequency region.In the second part of the thesis, a novel planar power transformer with hybrid core structure has been designed and evaluated in the MHz frequency region. The design guidelines of the energy efficient high frequency planar power transformerfor the given power transfer application have been proposed. The designed corebased planar transformer has been characterized up to the power level of 50W and possess a power density of 47W/cm3 with maximum energy efficiency of 97%. This transformer has been evaluated successfully in the resonant converter topology within the switching frequency range of 3 – 4.5MHz. The peak energy efficiency ofthe converter is reported to be 92% and the converter has been tested for the maximum power level of 45W, which is suitable for consumer applications such as laptop adapters. In addition to this, a record power density transformer has been designed with a custom made pot core and has been characterized in thefrequency range of 1 - 10MHz. The power density of this custom core transformer operating at 6.78MHz frequency is 67W/cm3 and with the peak energy efficiency of 98%.In conclusion, the research in this dissertation proposed a solution for obtaining high power density converters by designing the highly integrated, high frequency(1 - 10MHz) coreless and core based planar magnetics with energy efficiencies inthe range of 92 - 97%. This solution together with the latest semiconductor GaN/SiC switching devices provides an excellent choice to meet the requirements of the next generation ultra flat low profile switch mode power supplies (SMPS).

  • 16.
    Ambatipudi, Radhika
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Kotte, Hari Babu
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Bertilsson, Kent
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    High Performance Planar Power Transformer with High Power Density in MHz Frequency Region for Next Generation Switch Mode Power Supplies2013In: 2013 Twenty-Eighth Annual IEEE Applied Power Electronics Conference And Exposition (APEC 2013), IEEE conference proceedings, 2013, 2139-2143 p.Conference paper (Refereed)
    Abstract [en]

    The authors report the utilization of the core based transformer for power transfer applications with high power density and high energy efficiency in the MHz frequency region. A custom made POT core center tapped transformer of 4:1:1 turn’s ratio using novel winding strategy with the core diameter of 16mm is designed and evaluated. The designed transformer has been characterized using sinusoidal excitation for a given output power in the frequency range of 1 – 10MHz and determined the operating frequency region of the transformer. The power tests of the transformer has been carried out up to the power level of 62W at an operating frequency of 6.78MHz with a peak energy efficiency of 98.5% resulting in the record power density of ~1100W/in3. The designed transformer has been characterized using class E isolated DC-DC converter topology at an output power of approximately 18W. The simulated energy efficiency of the converter is 88.5% under the full load condition. This work provides the significant step for the development of next generation high power density isolated converters (both AC/DC and DC/DC) in MHz frequency region

  • 17.
    Amir, Yousaf Muhammad
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Thörnberg, Benny
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    High Precision Laser Scanning of Metallic Surfaces2017In: International Journal of Optics, ISSN 1687-9384, E-ISSN 1687-9392, 4134205Article in journal (Refereed)
    Abstract [en]

    Speckle noise, dynamic range of light intensity, and spurious reflections are major challenges when laser scanners are used for 3D surface acquisition. In this work, a series of image processing operations, that is, Spatial Compound Imaging, High Dynamic Range Extension, Gray Level Transformation, and Most Similar Nearest Neighbor are proposed to overcome the challenges coming from the target surface. A prototype scanner for metallic surfaces is designed to explore combinations of these image processing operations. The main goal is to find the combination of operations thatwill lead to the highest possible robustness andmeasurement precision at the lowest possible computational load. Inspection of metallic tools where the surface of its edge must be measured at micrometer precision is our test case. Precision of heights measured without using the proposed image processing is firstly analyzed to be +/- 7.6 mu m at 68% confidence level. The best achieved height precision was +/- 4.2 mu m. This improvement comes at 24 times longer processing time and five times longer scanning time. Dynamic range extension of the image capture improves robustness since the numbers of saturated or underexposed pixels are substantially reduced. Using a high dynamic range (HDR) camera offers a compromise between processing time, robustness, and precision.

  • 18.
    Anastasopoulos, M.
    et al.
    European Spallation Source, Lund.
    Bebb, R.
    European Spallation Source, Lund.
    Berry, K.
    Instrument and Source Division, Spallation Neutron Source, United States.
    Birch, J.
    Linköping University.
    Bryś, T.
    European Spallation Source, Lund.
    Buffet, J. -C
    Institute Laue Langevin, France.
    Clergeau, J. -F
    Institute Laue Langevin, France.
    Deen, P. P.
    European Spallation Source, Lund.
    Ehlers, G.
    Quantum Condensed Matter Division, Spallation Neutron Source, United States.
    Van Esch, P.
    Institute Laue Langevin, France.
    Everett, S. M.
    Instrument and Source Division, Spallation Neutron Source, United States.
    Guerard, B.
    Institute Laue Langevin, France.
    Hall-Wilton, Richard
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design. European Spallation Source, Lund.
    Herwig, K.
    Instrument and Source Division, Spallation Neutron Source, United States.
    Hultman, L.
    Linköping University.
    Höglund, C.
    Linköping University; European Spallation Source, Lund.
    Iruretagoiena, I.
    European Spallation Source, Lund.
    Issa, F.
    European Spallation Source, Lund.
    Jensen, J.
    Linköping University.
    Khaplanov, A.
    European Spallation Source, Lund.
    Kirstein, O.
    European Spallation Source, Lund.
    Higuera, I. L.
    European Spallation Source, Lund.
    Piscitelli, F.
    European Spallation Source, Lund.
    Robinson, L.
    European Spallation Source, Lund.
    Schmidt, S.
    European Spallation Source, Lund.
    Stefanescu, I.
    European Spallation Source, Lund.
    Multi-Grid detector for neutron spectroscopy: Results obtained on time-of-flight spectrometer CNCS2017In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 12, no 4, P04030Article in journal (Refereed)
    Abstract [en]

    The Multi-Grid detector technology has evolved from the proof-of-principle and characterisation stages. Here we report on the performance of the Multi-Grid detector, the MG.CNCS prototype, which has been installed and tested at the Cold Neutron Chopper Spectrometer, CNCS at SNS. This has allowed a side-by-side comparison to the performance of 3He detectors on an operational instrument. The demonstrator has an active area of 0.2 m2. It is specifically tailored to the specifications of CNCS. The detector was installed in June 2016 and has operated since then, collecting neutron scattering data in parallel to the He-3 detectors of CNCS. In this paper, we present a comprehensive analysis of this data, in particular on instrument energy resolution, rate capability, background and relative efficiency. Stability, gamma-ray and fast neutron sensitivity have also been investigated. The effect of scattering in the detector components has been measured and provides input to comparison for Monte Carlo simulations. All data is presented in comparison to that measured by the 3He detectors simultaneously, showing that all features recorded by one detector are also recorded by the other. The energy resolution matches closely. We find that the Multi-Grid is able to match the data collected by 3He, and see an indication of a considerable advantage in the count rate capability. Based on these results, we are confident that the Multi-Grid detector will be capable of producing high quality scientific data on chopper spectrometers utilising the unprecedented neutron flux of the ESS.

  • 19.
    Andersson, Henrik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Manuilskiy, Anatoliy
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Gao, Jinlan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Lidenmark, Cecilia
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Sidén, Johan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Forsberg, Sven
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Unander, Tomas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design. Dewire AB, Sundsvall 85185, Sweden.
    Nilsson, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Investigation of Humidity Sensor Effect in Silver Nanoparticle Ink Sensors Printed on Paper2014In: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 14, no 3, Art. no. 6615915- p.Article in journal (Refereed)
    Abstract [en]

    Thin inkjet-printed tracks of silver nanoparticles have previously been observed to show a non-reversible decrease in resistance when exposed to a high degree of relative humidity and thus providing sensor functionality with a memory effect. This paper provides a more in-depth explanation of the observed humidity sensor effect that originates from inkjet-printed silver nanoparticle sensors on a paper substrate. It is shown that the geometry of the sensor has a large effect on the sensor's initial resistance, and therefore also on the sensor's resistive dynamic range. The importance of the sensor geometry is believed to be due to the amount of solvent from the ink interacting with the coating of the paper substrate, which in turn enables the diffusion of salts from the paper coating into the ink and thus affecting the silver ink.

  • 20.
    Andersson, Henrik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Manuilskiy, Anatoliy
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Haller, Stefan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Hummelgård, Magnus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Sidén, Johan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Hummelgård, Christine
    Acreo Swedish ICT AB.
    Olin, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Nilsson, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Assembling surface mounted components on ink-jet printed double sided paper circuit board2014In: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 25, Art. no. 094002- p.Article in journal (Refereed)
    Abstract [en]

    Printed electronics is a rapidly developing field where many components can already be manufactured on flexible substrates by printing or by other high speed manufacturing methods. However, the functionality of even the most inexpensive microcontroller or other integrated circuit is, at the present time and for the foreseeable future, out of reach by means of fully printed components. Therefore, it is of interest to investigate hybrid printed electronics, where regular electrical components are mounted on flexible substrates to achieve high functionality at a low cost. Moreover, the use of paper as a substrate for printed electronics is of growing interest because it is an environmentally friendly and renewable material and is, additionally, the main material used for many packages in which electronics functionalities could be integrated. One of the challenges for such hybrid printed electronics is the mounting of the components and the interconnection between layers on flexible substrates with printed conductive tracks that should provide as low a resistance as possible while still being able to be used in a high speed manufacturing process. In this article, several conductive adhesives are evaluated as well as soldering for mounting surface mounted components on a paper circuit board with inkjet printed tracks and, in addition, a double sided Arduino compatible circuit board is manufactured and programmed.

  • 21.
    Andersson, Henrik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Manuilskiy, Anatoliy
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Lidenmark, Cecilia
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Gao, Jinlan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Öhlund, Thomas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Forsberg, Sven
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Örtegren, Jonas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Schmidt, Wolfgang
    Schoeller Technocell GmbH and Co. KG, Burg Gretesch, D-49086, Osnabrück, Germany.
    Nilsson, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    The influence of paper coating content on room temperature sintering of silver nanoparticle ink2013In: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 24, no 45, Art. no. 455203- p.Article in journal (Refereed)
    Abstract [en]

    The resistance of inkjet printed lines using a silver nanoparticle based ink can be very dependent on the substrate. A very large difference in resistivity was observed for tracks printed on paper substrates with aluminum oxide based coatings compared to silica based coatings. Silica based coatings are often cationized with polymers using chloride as a counter ion. It is suggested that the precipitation of silver salts is the cause of the high resistivity, since papers pretreated with salt solutions containing ions that precipitate silver salts gave a high resistance. Silver nitrate has a high solubility and paper pretreated with nitrate ions gave a low resistivity without sintering. The results obtained show that, by choosing the correct type of paper substrate, it is possible to manufacture printed structures, such as interconnects on paper, without the need for, or at least to reduce the need for, post-print sintering. This phenomenon is, of course, ink specific. Inks without or with a low silver ion content are not expected to behave in this manner. In some sensor applications, a high resistivity is desired and, by using the correct combination of ink and paper, these types of sensors can be facilitated.

  • 22.
    Andersson, Henrik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Manuilskiy, Anatoliy
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Sidén, Johan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Gao, Jinlan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Hummelgård, Magnus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Kunninmel, Gokuldev
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Nilsson, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Chemically programmed ink-jet printed resistive WORM memory array and readout circuit2014In: Materials Research Express, ISSN 2053-1591, Vol. 1, no 3, 035021- p.Article in journal (Refereed)
    Abstract [en]

    In this paper an ink-jet printed write once read many (WORM) resistive memory fabricated on paper substrate is presented. The memory elements are programmed for different resistance states by printing triethylene glycol monoethyl ether on the substrate before the actual memory element is printed using silver nano particle ink. The resistance is thus able to be set to a broad range of values without changing the geometry of the elements. A memory card consisting of 16 elements is manufactured for which the elements are each programmed to one of four defined logic levels, providing a total of 4294 967 296 unique possible combinations. Using a readout circuit, originally developed for resistive sensors to avoid crosstalk between elements, a memory card reader is manufactured that is able to read the values of the memory card and transfer the data to a PC. Such printed memory cards can be used in various applications.

  • 23.
    Andersson, Henrik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Sidén, Johan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Skerved, Vincent
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Li, Xiaotian
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Gyllner, Linnea
    Iniss Triab AB, S-16250 Vällingby.
    Soldering Surface Mount Components onto Inkjet Printed Conductors on Paper Substrate using Industrial Processes2016In: IEEE Transactions on Components, Packaging, and Manufacturing Technology, ISSN 2156-3950, E-ISSN 2156-3985, Vol. 6, no 3, 478-485 p., 7422029Article in journal (Refereed)
    Abstract [en]

    This paper describes mounting of standard surface mount component packages on a paper substrate using an industrial solder process with a low-temperature solder. The use of paper as a substrate for printed flexible electronics is becoming more and more widespread as an alternative to the more commonly used plastic substrates, such as polyethylene and polyimide. Paper has the benefits of being environmentally friendly, recyclable, and renewable, as well as inexpensive. It is shown that it is possible to mount standard surface mount device components on paper substrates using low-temperature solder in an industrial soldering process. The contact resistances obtained are mostly low, although the yield of functioning contacts is low. The reason is cracking of the substrate coating layer that goes through the printed silver tracks. It was observed that the cracks appear mostly close to the contact pads, the most likely cause is thermal mismatch between the coating layer and solder and also thermal expansion of the photo paper resin coating. The smallest component package size, 0201, resulted in the highest yield of >80% with decreasing yield for larger package sizes.

  • 24.
    Andersson, Karl
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Intelligent control system for street lighting2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Street lighting is an important aspect of infrastructure in terms of both safety and comfort, but it also consumes a lot of energy. Unused light is a waste of energy, and without any form of control of the street lighting, this problem will continue to increase along with the expansion of road networks. The aim of this thesis is to propose an intelligent control system for street lighting that can adapt to the velocity of individual road users, to investigate if this could provide ways to improve the efficiency of street lighting. Previous control approaches include systems based on ambient light intensity or presence of road users, but no studies were found in which illumination adapts to the velocity of road users. The project involves three main steps, including a literature review, a system implementation and evaluation. In the proposed system, street lights cooperate to detect road users and calculate their velocities in order to adapt the illumination and make it follow their movement. It can be concluded from the evaluation results that the velocity readings help further optimize the illumination control in comparison to systems that do not consider velocity. The velocity readings make it possible to only illuminate the roadway in the direction of travel, while also adapting the distance of illumination to the recorded speed. The proposed control scheme is considered a viable solution for reducing the amount of unused light, consequently reducing the energy consumption of street lighting.

  • 25.
    Andersson, Karl
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    PLC Lab Station: An Implementation of External Monitoring and Control Using OPC2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The PLC is frequently used when implementing automated control, which is animportant part of many modern industries. This thesis has been carried out incollaboration with ÅF Consult in Sundsvall, who were in need of a PLC labstation for educational purposes. The overall aim of this thesis has been todesign and construct such a lab station and also to implement a solution forexternal monitoring and control possibilities. The methodology of this projecthas included a literary study, followed by the implementation of the actualsolutions and finally an evaluation of the project. The finished lab stationincludes a conveyor belt and a robotic arm controlled using two PLCs. Theconveyor belt is designed to be able to store, transport, differentiate and sortsmall cubes of various materials, and the robotic arm is designed as a pick-andplacedevice that can move the cubes between different positions on the labstation. The monitoring and control solution is set up using an OPC clientserverconnection on a PC and it provides a graphical user interface where thelab station can be monitored and controlled externally. The lab station offersdiverse functionality, but due to some inconsistency in the included equipmentit is not entirely reliable. The external monitoring and control solution alsoprovides good functionality, but the time frame of the project resulted in a lessextensive implementation than originally intended. The overall solutions are,however, considered to offer a functional and proper platform for educationalpurposes.

  • 26.
    Anwar, Qaiser
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Imran, Muhammad
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    O'Nils, Mattias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Intelligence Partitioning as a Method for Architectural Exploration of Wireless Sensor Node2017In: Proceedings of the International Conference on Computational Science and Computational Intelligence (CSCI), 2016., IEEE Press, 2017, 935-940 p., 7881473Conference paper (Refereed)
    Abstract [en]

    Embedded systems with integrated sensing, processing and wireless communication are driving future connectivity concepts such as Wireless Sensor Networks (WSNs) and Internet of Things (IoTs). Because of resource limitations, there still exists a number of challenges such as low latency and energy consumption to realize these concepts to full potential. To address and understand these challenges, we have developed and employed an intelligence partitioning method which generates different implementation alternatives by distributing processing load across multiple nodes. The task-to-node mapping has exponential complexity which is hard to compute for a large scale system. Regarding this, our method provides recommendation to handle and minimize such complexity for a large system. Experiments on a use-case concludes that the proposed method is able to identify unfavourable architecture solutions in which forward and backword communication paths exists in task-to-node mapping. These solution can be avoided for further architectural exploration, thus limiting the space for architecture exploration of a sensor node.

  • 27.
    Anwar, Qaiser
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Malik, Abdul Waheed
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Thörnberg, Benny
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Design of coded reference labels for indoor optical navigation using monocular camera2013In: 2013 International Conference on Indoor Positioning and Indoor Navigation, IPIN 2013, IEEE Computer Society, 2013, Art. no. 6817925- p.Conference paper (Refereed)
    Abstract [en]

    We present a machine vision based indoor navigation system. The paper describes a pose estimation of machine vision system by recognizing rotationally independent optimized color reference labels combined with a geometrical camera calibration model, which determines a set of camera parameters. A reference label carries one byte of information, which can be uniquely designed for various values. More than four reference labels are used in the image to calculate the localization coordinates of the system. An algorithm in Matlab has been developed so that a machine vision system can recognize N number of labels at any given orientation. In addition, a one channel color technique is applied in segmentation process, due to this technique the number of segmented image components is reduced significantly, limiting the memory storage requirement and processing time. The algorithm for pose estimation is based on direct linear transformation (DLT) method with a set of control reference labels in relation to the camera calibration model. From the experiments we concluded that the pose of the machine vision system can be calculated with relatively high precision, in the calibrated environment of reference labels. © 2013 IEEE.

  • 28.
    Ashraf, Shakeel
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Design and Integration of Infrared Absorber Structures into Polymer Membranes based Thermal Detectors2015Licentiate thesis, comprehensive summary (Other academic)
  • 29.
    Ashraf, Shakeel
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Mattsson, Claes
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Fondell, Mattis
    Helmholtz Zentrum, Inst Methods & Instrumentat Synchrotron Radiat Re, Berlin, Germany.
    Lindblad, Andreas
    Uppsala Univ, Dept Chem, Angstrom Lab, Uppsala, Sweden.
    Thungström, Göran
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Surface modification of SU-8 for metal/SU-8 adhesion using RF plasma treatment for application in thermopile detectors2015In: Materials Research Express, ISSN 2053-1591, Vol. 2, no 8, 086501Article in journal (Refereed)
    Abstract [en]

    This article reports on plasma treatment of SU-8 epoxy in order to enhance adhesive strength for metals. Its samples were fabricated on standard silicon wafers and treated with (O2 & Ar) RF plasma at a power of 25W at a low pressure of (3×10-3 torr) for different time spans (10 sec – 70 sec). The sample surfaces were characterized in terms of contact angle, surface (roughness and chemistry) and using a tape test. During the contact angle measurement, it was observed that the contact angle was reduced from 73° to 5° (almost wet) and 23° for (O2 & Ar) treated samples, respectively. The RMS surface roughness was significantly increased by 21.5% and 37.2% for (O2 & Ar) treatment, respectively. A pattern of metal squares was formed on the samples using photolithography for a tape test. An adhesive tape was applied to the samples and peeled off at 180o. The maximum adhesion results, more than 90%, were achieved for the O2-treated samples, whereas the Ar-treated samples showed no change. The XPS study shows the formation of new species in the O2-treated sample compared to the Ar-treated samples. The high adhesive results were due to the formation of hydrophilic groups and new O2 species in the O2-treated samples, which were absent in Ar-treated samples.

  • 30.
    Ashraf, Shakeel
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Mattsson, Claes
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Thungström, Göran
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Fabrication of a mid-Ir sensitive thermopile detector2016In: Proceedings of IEEE Sensors, IEEE, 2016, 7808481Conference paper (Refereed)
    Abstract [en]

    This paper reports on the integration of a multilayered mid-infrared absorber structure into a SU-8 epoxy membrane-based thermopile detector. The absorber structure was designed and simulated using transfer matrix theory. The fabricated absorber structures were characterized through Fourier transform infrared spectroscopy. The structure shows an absorption of more than 95% in the wavelength range of 3.30pm–5pm for simulations, and 3.2pm–5.47pm for FTIR measurements. The complete fabrication process of a thermopile detector including the integration of a multilayered absorber structure has been presented. A MEMS based infrared emitter was used to characterize the fabricated detector. The serial resistance was measured to 315 kΩ and the responsivity was calculated to 57.5 Vmm2W−1 at a wavelength of 4.26pm. The time constant for the fabricated detector was estimated to around 21ms.

  • 31.
    Ashraf, Shakeel
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Mattsson, Claes
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Thungström, Göran
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Rödjegard, Henrik
    Design of a multilayered absorber structure based on SU-8 epoxy for broad and efficient absorption inMid-IR sensitive thermal detectors2014In: Proceedings, 2014, 938-941 p.Conference paper (Refereed)
    Abstract [en]

    This paper reports on design, simulation and fabrication of a multilayered interferometric absorption structure with a broad absorption in the mid-infrared band. This region is used for IR based CH4 and CO2 detection. The structure consists of five layers of different thickness. The structure consists of one mirror layer of aluminium, two SU-8 epoxy layers and two thin titanium layers. This structure has been fabricated on a silicon substrate and verified for its absorption properties through Fourier transform infrared spectroscopy. The fabricated structure has been compared with simulations are performed using transfer matrix theory. The structure shows more than 90% absorption in the wavelength range of 3.20μm - 5.35μm for simulations and 3.13μm - 5.47μm for FT-IR measurements. The transmission and reflection of SU-8 epoxy was measured using FT-IR (that), resulting in a calculated absorption between 10 - 20% in the area of interest (3μm - 6μm). The use of SU-8 epoxy as dielectric medium, allows for direct integration of the structure into the membrane of a SU-8 membrane based thermopile. The integration results in minimum increase of the thermal capacitance and conductance, which results in maximum detector sensitivity and minimum time constant.

  • 32.
    Ashraf, Shakeel
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Mattsson, Claes
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Thungström, Göran
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Rödjegard, Henrik
    SenseAir AB, Delsbo, Sweden.
    Integration of an interferometric IR absorber into an epoxy membrane based CO2 detector2014In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 9, no 5, Art. no. C05035- p.Article in journal (Refereed)
    Abstract [en]

    Measurements of carbon dioxide levels in the environment are commonly performedby using non-dispersive infrared technology (NDIR). Thermopile detectors are often used in NDIRsystems because of their non-cooling advantages. The infrared absorber has a major influence onthe detector responsivity. In this paper, the fabrication of a SU-8 epoxy membrane based Al/Bithermopile detector and the integration of an interferometric infrared absorber structure of wavelength around 4 µ m into the detector is reported. The membrane of thermopile detector has beenutilized as a dielectric medium in an interferometric absorption structure. By doing so, a reduction in both thermal conductance and capacitance is achieved. In the fabrication of the thermopile,metal evaporation and lift off process had been used for the deposition of serially interconnectedAl/Bi thermocouples. Serial resistance of fabricated thermopile was measured as 220 kΩ. Theresponse of fabricated thermopile detector was measured using a visible to infrared source of radiation flux 3.23 mW mm−2. The radiation incident on the detector was limited using a band passfilter of wavelength 4.26 µ m in front of the detector. A responsivity of 27.86 V mm2W−1at roomtemperature was achieved using this setup. The fabricated detector was compared to a referencedetector with a broad band absorber. From the comparison it was concluded that the integratedinterferometric absorber is functioning correctly.

  • 33.
    Bader, Sebastian
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    On the lifetime and usability of environmental monitoring wireless sensor networks2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Wireless sensor networks have been demonstrated, at an early stage in their development, to be a useful measurement technology for environmental monitoring applications. Based on their independence from existing infrastructures, wireless sensor networks can be deployed in virtually any location and provide sensor samples in a spatial and temporal resolution, which otherwise would only be achievable at high cost or involve significant work by humans.The feasibility of the usage of wireless sensor networks in real-world applications, however, is only maintained if certain technological challenges are overcome. Amongst these challenges, are the limited lifetime of the distributed sensor nodes, and user interfaces, which allow for the technology to be utilized in an efficient manner. Contributions to the solution of these challenges have been the objective of this thesis.

    After an analysis of the contributions wireless sensor networks can provide

    to the application domain of environmental monitoring, and the introduction

    to the restrictions, which are posed by a limited operational lifetime and low

    system usability, these issues are addressed at the system level of sensor nodedevices.

    The lifetime of sensor nodes, which is closely linked to the lifetime of the

    complete wireless sensor network, is addressed with regards to the energy

    efficiency of nodes, as well as the utilization of solar energy harvesting in

    order to increase the available energy resources. With respect to energy

    efficiency, an analysis has been performed of the contributions to the energy

    consumption of environmental monitoring sensor nodes, which leads to the

    desire to minimize the nodes' duty cycles and quiescent currents. A sensor

    node design is presented, which features energy efficiency as a key attribute by utilizingmodern semiconductor architectures. Moreover, an argument for the usage of synchronization-based, contention-free communication is made

    in order to reduce active communication periods and, thus, the duty cycle

    of a sensor node. A synchronization method with its focus on low protocol

    overhead is introduced as a basis for such communication forms. After an initial feasibility study in relation to using battery-less solar energy

    harvesting architectures in locations with limited solar irradiation, multiple

    architectural implementations are analyzed in a comparative manner.

    Among these comparisons is an analysis of short-termenergy storage devices in the form of double-layer capacitors and thin-film batteries, which provide prolonged component lifetimes than those for conventional secondary batteries, but which can only buffer for short periods of time due to their limited energy capacity. In order to be able to dimension such energy harvesting systems with respect to the individual application constraints at hand, state of charge simulations are proposed. Amethod for such simulations is presented and demonstrated for the implementation of an energy harvester model on a component basis. While the modeling in this manner is time consuming, the model can predict the state of charge of the energy buffer in the architecture with a high level of accuracy. Finally, a method for the systematic evaluation of solar energy harvesting architectures is presented. The presented method can be summarized as a solar energy harvesting testbed, which utilizes configurable energy harvesting circuits in order to create a deploy-once-test-many type of system. The output results of this testbed can significantly improve

    the efficiency of architecture comparisons and system modeling.

    Contributions to the improvement of the usability of wireless sensor nodes

    are made on two separate levels, namely, developer usability and end user

    usability. A method for the programming of sensor nodes based on hierarchical finite state machines is presented, which improves the usability of software development by creating familiarity for technically experienced

    users. Moreover, the utilization of finite state machine principles allows

    for the software to be developed in a systematic andmodular manner. As

    implemented applications typically require to be verified, which, in the environmental monitoring domain, usually results in outdoor deployments,

    usability considerations for sensor nodes are presented, which can simplify

    this process. Special attention has been paid in order for these improvements to be achieved with low overheads. While software development is a familiar concept for most system developers, this is not the case for the end users of these systems, who are typically domain experts. In order to allow for wireless sensor nodes to be operated

    by domain experts, a method for the configuration of sensor nodes has been proposed.The method uses a combination of graphical specification of the node behavior and a configurable sensor node. Theevaluation of this method, which has been based on a proof-of-concept implementation, demonstrated that the performance can remain high, while end users, without technical experience, are enabled to configure sensor nodes without prior training.

    In summary, the contributions, presented in this thesis, address system

    lifetime and usability with regards to the sensor node level. The results have

    led to the implementation of an energy efficient sensor node, which allows for the operation frombattery-less solar energy harvesting sources. Furthermore, support tools for the implementation of these nodes, both on the hardware and software level, have been proposed.

  • 34.
    Bader, Sebastian
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Krämer, Matthias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Lawal, Najeem
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    O'Nils, Mattias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Oelmann, Bengt
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Remote image capturing with low-cost and low-power wireless camera nodes2014In: Proceedings of IEEE Sensors, IEEE Sensors Council, 2014, 730-733 p., 6985103Conference paper (Refereed)
    Abstract [en]

    Wireless visual sensor networks provide featurerich information about their surrounding and can thus be used as a universal measurement tool for a great number of applications. Existing solutions, however, have mainly been focused on high sample rate applications, such as video surveillance, object detection and tracking. In this paper, we present a wireless camera node architecture that targets low sample rate applications (e.g., manual inspections and meter reading). The major design considerations are a long system lifetime, a small size and a low production cost.We present the overall architecture with its individual design choices, and evaluate the architecture with respect to its application constraints. With a typical image acquisition cost of 1.5 J for medium quality images and a quiescent power demand of only 7 uW, the evaluation results demonstrate that long operation periods of the order of years can be achieved in low sample rate scenarios.

  • 35.
    Bader, Sebastian
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Krämer, Matthias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Oelmann, Bengt
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    A Domain-Specific Platform for Research in Environmental Wireless Sensor Networks2013In: SENSORCOMM 2013, The Seventh International Conference on Sensor Technologies and Applications / [ed] Sergey Yurish, IFSA - Barcelona, Spain Muhammad Shakeel Virk, Narvik University College, Norway, 2013, 200-207 p.Conference paper (Refereed)
    Abstract [en]

    Wireless Sensor Networks have the ability to improve a multitude of existing application domains. These networks are built up from a number of sensor nodes with sensing, communication and processing capabilities and the performance of the networked system is defined by the performance of the node platform it is based on. In this paper, we present SENTIO-em, a hardware platform for research in the environmental monitoring application domain. Based on the application domain requirements, the architecture and implementation of SENTIO-em is optimized for environmental monitoring constraints, while it is sufficiently flexible to be reused for different applications within the domain. The architecture of the platform is presented and evaluated under both laboratory and different environmental conditions. The obtained results are compared to a number of existing node platforms, demonstrating that SENTIO-em provides high energy efficiency with increased processing performance, short state transition times, and low quiescent currents.

  • 36.
    Bader, Sebastian
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Krämer, Matthias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Oelmann, Bengt
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    A Testbed for the Evaluation of Solar Energy Harvesting ArchitecturesManuscript (preprint) (Other academic)
  • 37.
    Bader, Sebastian
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Ma, Xinyu
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Oelmann, Bengt
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    On the Modeling of Solar-Powered Wireless Sensor Nodes2014In: Journal of Sensor and Actuator Networks, ISSN 2224-2708, Vol. 3, no 3, 207-223 p.Article in journal (Refereed)
    Abstract [en]

    Solar energy harvesting allows for wireless sensor networks to be operated over extended periods of time. In order to select an appropriate harvesting architecture and dimension for its components, an effective method for the comparison of system implementations is required. System simulations have the capability to accomplish this in an accurate and efficient manner. In this paper, we evaluate the existing work on solar energy harvesting architectures and common methods for their modeling. An analysis of the existing approaches demonstrates a mismatch between the requirement of the task to be both accurate and efficient and the proposed modeling methods, which are either accurate or efficient. As a result, we propose a data-driven modeling method based on artificial neural networks for further evaluation by the research community. Preliminary results of an initial investigation demonstrate the capability of this method to accurately capture the behavior of a solar energy harvesting architecture, while providing a time-efficient model generation procedure based on system-level data.

  • 38.
    Bader, Sebastian
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Oelmann, Bengt
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Concealing the complexity of node programming in wireless sensor networks2013In: Proceedings of the 2013 IEEE 8th International Conference on Intelligent Sensors, Sensor Networks and Information Processing: Sensing the Future, ISSNIP 2013, IEEE conference proceedings, 2013, 177-182 p.Conference paper (Refereed)
    Abstract [en]

    There is a significant potential for Wireless sensor networks to be used as a general distributed measurement and monitoring system. The integration of computation, communication and sensing enables smart sensors to be built that can be adapted to a plethora of application requirements and allow for automated data collection throughout the network. However, the potential end users of this systems are domain experts, who usually do not possess the technical expertise to program, and thus operate, wireless sensor nodes, which prohibits the technology from becoming off-the-shelf equipment. In this paper, we present a method which enables the complexity of programming sensor nodes to be concealed in order to allow domain experts to use wireless sensor networks in basic applications without the requirement of technical assistance. We propose to use a computer-based specification entry, which generates a configuration parameter set to adjust the sensor node's application behavior. The method has been implemented in a proof-of-concept system and evaluated with test subjects who possess limited programming skills. The results show that users without any prior programming knowledge, or experience with embedded systems, are capable of configuring a sensor node according to a given application scenario within minutes.

  • 39.
    Bader, Sebastian
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Oelmann, Bengt
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Short-term energy storage for wireless sensor networks using solar energy harvesting2013In: Networking, Sensing and Control (ICNSC), 2013 10th IEEE International Conference on, IEEE , 2013, 71-76 p.Conference paper (Refereed)
    Abstract [en]

    Solar energy harvesting has become a common energy source for outdoor wireless sensor networks. To avoid the lifetime limitation of traditional secondary battery technologies in these systems, energy harvesting architectures with short-term energy storage can be chosen. These technologies offer long shelf-life and many recharge cycles, but can buffer for only short periods of time due to their small storage capacity. In this paper we present the analysis of two of these short-term energy storage devices, namely double layer capacitors and thin-film batteries. We present different harvesting architectures using these buffer elements and compare their advantages and disadvantages in relation to being used in low-power wireless sensor network applications. Experimental results show that both storage types are viable options for the intended application, each bringing their own strengths and weaknesses.

  • 40.
    Bakar, Muhammad Abu
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Design and optimization of soft switched power converters for low and medium power applications2016Licentiate thesis, comprehensive summary (Other academic)
  • 41.
    Bakar, Muhammad Abu
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Alam, Farhan Muhammad
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Bertilsson, Kent
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    A phase shifted full bridge converter with novel control over the leakage inductance2016In: 2016 18TH EUROPEAN CONFERENCE ON POWER ELECTRONICS AND APPLICATIONS (EPE'16 ECCE EUROPE), Institute of Electrical and Electronics Engineers (IEEE), 2016, 7695545Conference paper (Refereed)
    Abstract [en]

    The electronics industry is progressing towards the high density board solutions due to the requirement of compact and intelligent electronic systems. In order to meet the industry demands, the power system is required to be of high power density. This article proposes one of the solution to improve the power density for the medium power applications. In phase shifted full bridge converter, the intrinsic leakage inductance of the main transformer is not high enough to obtain the zero voltage switching of the power switches for the entire operating conditions. An additional shim inductor is usually connected in series with the primary winding of the main transformer to increase the collective leakage inductance. This additional shim inductor degrades the power density of the converter. This paper proposes a method to embed and control the resonance inductance inside the main transformer. In addition to the increased inter-winding spacing, this paper proposes a practical approach to integrate the ferrite rods inside the main transformer for further increase in the leakage inductance. A power transformer is constructed and investigated by using the modelled equations to estimate the leakage inductance. A prototype phase shifted full bridge converter is also developed to investigate the performance of the proposed transformer. The converter is designed for the switching frequency of 400kHz, and tested up to 600watts output power at the input voltage of 200Vdc. The performance of the proposed converter is also compared with the converter of using an external inductor. The investigations show that, in addition to the improved power density, the converter with the proposed transformer is more efficient than the converter with the traditional transformer.

  • 42.
    Bakar, Muhammad Abu
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Bertilsson, Kent
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    An improved modelling and construction of power transformer for controlled leakage inductance2016In: Environment and Electrical Engineering (EEEIC), 2016 IEEE 16th International Conference on, IEEE, 2016Conference paper (Refereed)
    Abstract [en]

    In this work, a transformer with increased leakage inductance for the soft switched power applications is presented as a practical solution by constructing a transformer with good control over the leakage inductance. An analytical reluctance based model is presented, which accurately predicts the leakage inductance. With the presented approach, a transformer is designed with a leakage inductance varying between 3-7μH. Increasing the efficiency and improving the power density has been the main focus of power electronics researchers in the recent years. In this regards, transformers with increased leakage inductance are becoming more popular in order to accomplish different soft switching concepts and for improving the power density.

  • 43.
    Bakar, Muhammad Abu
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Bertilsson, Kent
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Ambatipudi, Radhika
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    High frequency (MHz) soft switched flyback dc-dc converter using GaN switches and six-layered PCB transformer2016In: IET Conference Publications, UK: Institution of Engineering and Technology, 2016, Vol. 2016, 1-6 p., CP684Conference paper (Refereed)
    Abstract [en]

    The increased switching losses with increasing switching frequency are the biggest concerns in designing high power density converters. This paper presents the investigation of an energy efficient DC-DC flyback converter in combination with six layered printed circuit board transformer. The recorded efficiency of the low profile transformer for the frequency range of 1-5MHz is 98% at power density of 770W/in3. The proposed converter is characterized for frequencies up to 4MHz by using possible soft switching techniques such as Boundary Mode and Quasi Resonant Mode. The emerging Gallium Nitride (GaN FET) devices are used as power switch. The control is incorporated with Digital Signal Processor (dsPIC) for both the Boundary and Quasi Resonant Modes of operations. The proposed flyback DC-DC converter is tested on a prototype Printed Circuit Board (PCB). The performance of the proposed converter is investigated for the telecom input voltage range of 36-72Vdc. The maximum obtained energy efficiency of the converter is about 94%. According to the authors' knowledge, this is the maximum efficiency ever achieved in flyback converters switching in MHz frequency range. The results are very encouraging for the development of high frequency, high power density and low cost isolated power converters.

  • 44.
    Ballabriga, Rafael
    et al.
    Cern.
    Alozy, Jerome
    Cern.
    Campbell, Michael
    Cern.
    Fiederle, Michael
    FMF Frieburg.
    Fröjdh, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Heijne, E H M
    Cern.
    Blaj, Gabriel
    Slac.
    Llopart, Xavier
    Cern.
    Pichotka, M
    Procz, Simon
    FMF Frieburg.
    Tlustos, Lukas
    Cern.
    Wong, Winnie
    Cern.
    The Medipix3RX: a high resolution, zero dead-time pixel detector readout chip allowing spectroscopic imaging2013In: Journal of Instrumentation, ISSN 1748-0221, Vol. 8, no 2, C02016- p.Article in journal (Refereed)
    Abstract [en]

    The Medipix3 chips have been designed to permit spectroscopic imaging in highly segmented hybrid pixel detectors. Spectral degradation due to charge sharing in the sensor has been addressed by means of an architecture in which adjacent pixels communicate in the analog and digital domains on an event-by-event basis to reconstruct the deposited charge in a neighbourhood prior to the assignation of the hit to a single pixel. The Medipix3RX chip architecture is presented. The first results for the characterization of the chip with 300 μm thick Si sensors are given. ~ 72e− r.m.s. noise and ~ 40e− r.m.s. of threshold dispersion after chip equalization have been measured in Single Pixel Mode of operation. The homogeneity of the image in Charge Summing mode is comparable to the Single Pixel Mode image. This demonstrates both modes are suitable for X-ray imaging applications.

  • 45.
    Balliu, Enkeleda
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Andersson, Henrik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Engholm, Magnus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Forsberg, Sven
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Olin, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Laser-assisted reduction of graphene oxide for paper based large area flexible electronics2016In: Proceedings of SPIE - The International Society for Optical Engineering, SPIE - International Society for Optical Engineering, 2016, Vol. 9736, 973610Conference paper (Refereed)
    Abstract [en]

    In this work we present a promising method for fabrication of conductive tracks on paper based substrates by laser assisted reduction of Graphene Oxide (GO). Printed electronics on paper based substrates is be coming more popular due to lower cost and recyclability. Fabrication of conductive tracks is of great importance where metal, carbon and polymer inks are commonly used. An emerging option is reduced graphene oxide (r-GO), which can be a good conductor. Here we have evaluated reduction of GO by using a 532 nm laser source, showing promising results with a decrease of sheet resistance from >100 M Ω/Sqr for unreduced GO down to 126 Ω/Sqr. without any observable damage to the paper substrates.

  • 46.
    Balliu, Enkeleda
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Andersson, Henrik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Hummelgård, Magnus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Olin, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Engholm, Magnus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Laser sintering of silver nano-particles inks printed on paper substrates2015In: Proceedings of SPIE - The International Society for Optical Engineering, SPIE - International Society for Optical Engineering, 2015, Art. no. 935112- p.Conference paper (Refereed)
    Abstract [en]

    In this work we have investigated the use of laser sintering of different ink-jet printed nano-particle inks (NPIs) on paper substrates. Laser sintering is shown to offer a fast and non-destructive way to produce paper based printed electronics. A continuous wave fiber laser source at 1064 nm is used and evaluated in combination with a galvo-scanning mirror system. A conductivity in order of 2.16 ∗ 107 S/m is reached for the silver NPI structures corresponding to nearly 35 % conductivity compared to that of bulk silver and this is achieved without any observable damage to the paper substrate. © 2015 SPIE.

  • 47.
    Balliu, Enkeleda
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Engholm, Magnus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Hellström, J.
    Cobolt AB, SE-171 54 Solna, Sweden.
    Elgcrona, G.
    Cobolt AB, SE-171 54 Solna, Sweden.
    Karlsson, H.
    Cobolt AB, SE-171 54 Solna, Sweden.
    Compact nanosecond pulsed single stage Yb-doped fiber amplifier2014In: Proceedings of SPIE - The International Society for Optical Engineering, 2014, Art. no. 895910- p.Conference paper (Refereed)
    Abstract [en]

    In this work we present a compact, nanosecond pulsed, single frequency, single stage Yb-doped fiber amplifier by using an overall fiber core diameter of 20 μm. The key component is a custom made, compact, ultra-low noise, single frequency ring-cavity solid state laser (SSL) at 1064 nm used as a master oscillator. The SSL can be designed to provide nanosecond pulses with pulse energies in the sub-mJ range. Our ultimate goal is to develop a compact linearly polarized, single frequency, nanosecond pulsed laser source in an all-fiber format. Short (less than 1m), highly Yb-doped fibers have been used in order to suppress non-linear effects. © 2014 SPIE.

  • 48.
    Bassam, Diraoui
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Lokal kompensering i Mellanspänningsnät2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Vid byte av luftledningar mot jordkabel kommer kapacitiva felström-mar att genereras. De kapacitiva felströmmarna ökar med större kabel-area. Rapporten behandlar problematiken med för stora bidrag av kapacitiva jordfelströmmar och dess inverkan på hela elnätet.

    Arbetetsfrågeställningar kommer att behandla utlokaliserad kompen-sation, oselektiv reläskyddsfunktion och skillnaden mellan långa led-ningar och stora nät. Syftet med uppsatsen är att belysa behovet av att utlokalisera kompensationen, bestämma antal och täthet av spolar som minskar kapacitiva strömmar på Alnön, samt titta på skillnaderna mellan långa och många ledningar både på tätortens och också lands-bygdens nät.

    I teoridelen tas teorier om olika typer av jordfelsskydds funktioner upp, lokal kompensering och skillnader mellan korta och långa markkabelns nät.

    Projektet är utfört genom utforskning av de metoder som används för att begränsa dem genererade kapacitiva felströmmen vid användning av markkablar.

    I slutsatsen kommer jag fram till att för förbättring av ledningsskydds-funktion på landsbygden måste kapacitiva strömmar transporteras genom kabeln i kortare sträckor. Detta kommer att minska spänningsfal-let över kabelns resistans och reaktans, eller att fördela nätet till små fack.

  • 49.
    Becker, J.
    et al.
    DESY, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany .
    Bianco, L.
    DESY, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany .
    Dinapoli, R.
    Paul-Scherrer-Institut(PSI), Villigen, Switzerland .
    Göttlicher, P.
    DESY, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany .
    Graafsma, Heinz
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Greiffenberg, D.
    Paul-Scherrer-Institut(PSI), Villigen, Switzerland .
    Gronewald, M.
    University of Bonn, Bonn, Germany .
    Henrich, B. H.
    Paul-Scherrer-Institut(PSI), Villigen, Switzerland .
    Hirsemann, H.
    DESY, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany .
    Jack, S.
    DESY, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany .
    Klanner, R.
    University of Hamburg, Hamburg, Germany .
    Krüger, H.
    University of Bonn, Bonn, Germany .
    Klyuev, A.
    DESY, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany .
    Lange, S.
    DESY, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany .
    Marras, A.
    DESY, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany .
    Mozzanica, A.
    Paul-Scherrer-Institut(PSI), Villigen, Switzerland .
    Schmitt, B.
    Paul-Scherrer-Institut(PSI), Villigen, Switzerland .
    Schwandt, J.
    University of Hamburg, Hamburg, Germany .
    Sheviakov, I.
    DESY, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany .
    Shi, X.
    Paul-Scherrer-Institut(PSI), Villigen, Switzerland .
    Trunk, U.
    DESY, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany .
    Zimmer, M.
    DESY, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany .
    Zhang, J.
    University of Hamburg, Hamburg, Germany .
    High speed cameras for X-rays: AGIPD and others2013In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 8, no 1, Art. no. C01042- p.Article in journal (Refereed)
    Abstract [en]

    Experiments at high pulse rate Free Electron Laser (FEL) facilities require new cameras capable of acquiring 2D images at high rates, handling large signal dynamic ranges and resolving images from individual pulses. The Adaptive Gain Integrated Pixel Detector (AGIPD) will operated with pulse rates and separations of 27000/s and 220 ns, respectively at European XFEL. Si-sensors, ASICs, PCBs, and FPGA logic are developed for a 1 Mega-pixel camera with 200 μm square pixels with per-pulse occupancies 104. Data from 3520 images/s will be transferred with 80 Gbits/s to a DAQ-system. The electronics have been adapted for use in other synchrotron light source detectors. 

  • 50.
    Becker, J.
    et al.
    Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Bianco, L.
    Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Göttlicher, P.
    Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Graafsma, Heinz
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design. Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Hirsemann, H.
    Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Jack, S.
    Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Klyuev, A.
    Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Lange, S.
    Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Marras, A.
    Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Rah, S.
    Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Sheviakov, I.
    Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Trunk, U.
    Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Zhang, J.
    Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Zimmer, M.
    Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany .
    Klanner, R.
    University of Hamburg, Germany .
    Schwandt, J.
    University of Hamburg, Germany .
    Dinapoli, R.
    PSI, Villigen, Switzerland.
    Greiffenberg, D.
    PSI, Villigen, Switzerland.
    Mozzanica, A.
    PSI, Villigen, Switzerland.
    Schmitt, B.
    PSI, Villigen, Switzerland.
    Shi, X.
    PSI, Villigen, Switzerland.
    Krüger, H.
    University of Bonn, Germany .
    The high speed, high dynamic range camera AGIPD2013In: IEEE Nuclear Science Symposium Conference Record, IEEE conference proceedings, 2013, Art. no. 6829504- p.Conference paper (Refereed)
    Abstract [en]

    The European X-Ray Free Electron Laser (XFEL) will provide ultra short, highly coherent X-ray pulses which will revolutionize scientific experiments in a variety of disciplines spanning physics, chemistry, materials science, and biology. One of the differences between the European XFEL and other free electron laser sources is the high pulse frequency of 4.5 MHz. The European XFEL will provide pulse trains, consisting of up to 2700 pulses separated by 220 ns (600 μs in total) followed by an idle time of 99.4 ms, resulting in a supercycle of 10 Hz. Dedicated fast 2D detectors are being developed, one of which is the Adaptive Gain Integrating Pixel Detector (AGIPD). AGIPD is based on the hybrid pixel technology. The design goals of the recently produced, radiation hard Application Specific Integrated Circuit (ASIC) with dynamic gain switching amplifiers are (for each pixel) a dynamic range of more than 10 4 12.4 keV photons in the lowest gain, single photon sensitivity in the highest gain, an analog memory capable of storing 352 images, and operation at 4.5 MHz frame rate. A vetoing scheme allows to maximize the number of useful images that are acquired by providing the possibility to overwrite any previously recorded image during the pulse train. The AGIPD will feature a pixel size of (200 μm)2 and a silicon sensor with a thickness of 500 μm. The image data is read out and digitized between pulse trains. © 2013 IEEE.

1234567 1 - 50 of 322
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf