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  • 1.
    Aasheim, Fanny
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Gestsson, Linnea
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Det spelar ingen roll hur du gör det - bara du gör det: Hur ett koncept kan utformas för att uppmana till motion utan att bidra till hälsohets2020Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
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  • 2.
    Abedini, Fereshteh
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    2D and 3D Halftoning for Appearance Reproduction2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The appearance of an object is determined by its chromatic and geometric qualities in its surrounding environment using four optical parameters: color, gloss, translucency, and surface texture. Reconstructing the appearance of objects is of great importance in many applications, including creative industries, packaging, fine-art reproduction, medical simulation, and prosthesis-making. Printers are reproduction devices capable of replicating objects’ appearance in 2D and 3D forms. With the introduction of new printing technologies, new inks and materials, and demands for innovative applications, creating accurate reproduction of the desired visual appearance has become challenging. Thus, the appearance reproduction workflow requires improvements and adaptations. 

    Accurate color reproduction is a critical quality measure in reproducing the desired appearance in any printing process. However, printers are devices with a limited number of inks that can either print a dot or leave it blank at a specific position on a substrate; hence, to reproduce different colors, optimal placement of the available inks is needed. Halftoning is a technique that deals with this challenge by generating a spatial distribution of the available inks that creates an illusion of the target color when viewed from a sufficiently large distance. Halftoning is a fundamental part of the color reproduction task in any full-color printing pipeline, and it is an effective technique to increase the potential of printing realistic and complex appearances. Although halftoning has been used in 2D printing for many decades, it still requires improvements in reproducing fine details and structures of images. Moreover, the emergence of new technologies in 3D printing introduces a higher degree of freedom and more parameters to the field of appearance reproduction. Therefore, there is a critical need for extensive studies to revisit existing halftoning algorithms and develop novel approaches to produce high quality prints that match the target appearance faithfully. This thesis aims at developing halftoning algorithms to improve appearance reproduction in 2D and 3D printing. 

    Contributions of this thesis in the 2D domain is a dynamic sharpness-enhancing halftoning approach, which adaptively varies the local sharpness of the halftone image based on different textures in the original image for realistic appearance printing. The results show improvements in halftone quality in terms of sharpness, preserving structural similarity, and decreasing color reproduction error. The main contribution of this thesis in 3D printing is extending a high quality 2D halftoning algorithm to the 3D domain. The proposed method is then integrated with a multi-layer printing approach, where ink is deposited at variable depths to improve the reproduction of tones and fine details. Results demonstrate that the proposed method accurately reproduces tones and details of the target appearance. Another contribution of this thesis is studying the effect of halftoning on the perceived appearance of 3D printed surfaces. According to the results, changing the dot placement based on the elevation variation of the underlying geometry can potentially control the perception of the 3D printed appearance. It implies that the choice of halftone may prove helpful in eliminating unwanted artifacts, enhancing the object’s geometric features, and producing a more accurate 3D appearance. The proposed methods in this thesis have been evaluated using different printing techniques.    

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  • 3.
    Abedini, Fereshteh
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Effect of halftones on printing iridescent colors2023In: IS&T Electronic Imaging: Color Imaging XXVIII: Displaying, Processng, Hardcopy, and Applications, The Society for Imaging Science and Technology, 2023, Vol. 35, p. 1-6Conference paper (Refereed)
    Abstract [en]

    The iridescent effect produced by structural color is difficult (if not impossible) to capture and print using traditional CMYK pigments. The so called RGB reflective pigments, nonetheless, generate angle-dependent colors by light interference. A layered surface structure generated by the pigments’ particles on a substrate reflects light waves of different wavelengths at different viewing angles according to the optical principle known as the Bragg Law. In this work, we have studied the influence of different halftone structures on printed images, produced with RGB reflective inks via screen printing. The main goal was to enhance the iridescence of a printed reproduction by studying the performance of different halftone algorithms on a screen printing process. We investigated the influence of different halftone structures in creating different spatial combinations of inks on a print to reproduce the image of an iridescent feathered headdress. We applied first-order, second-order, and structure-aware FM halftones to compare how they influence the reproduction of the material appearance of the object represented in the original image. The results show that the structure-ware halftones improve the representation of the image structures and details. Therefore, it could better convey the 3D surface features that produce iridescence in real feathers.

  • 4.
    Abedini, Fereshteh
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Gooran, Sasan
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Structure-Aware Color Halftoning with Adaptive Sharpness Control2022In: Journal of Imaging Science and Technology, ISSN 1062-3701, E-ISSN 1943-3522, Vol. 66, no 6, article id 060404Article in journal (Refereed)
    Abstract [en]

    Structure-aware halftoning algorithms aim at improving their non-structure-aware version by preserving high-frequency details, structures, and tones and by employing additional information from the input image content. The recently proposed achromatic structure-aware Iterative Method Controlling the Dot Placement (IMCDP) halftoning algorithm uses the angle of the dominant line in each pixels neighborhood as supplementary information to align halftone structures with the dominant orientation in each region and results in sharper halftones, gives a more three-dimensional impression, and improves the structural similarity and tone preservation. However, this method is developed only for monochrome halftoning, the degree of sharpness enhancement is constant for the entire image, and the algorithm is prohibitively expensive for large images. In this paper, we present a faster and more flexible approach for representing the image structure using a Gabor-based orientation extraction technique which improves the computational performance of the structure-aware IMCDP by an order of magnitude while improving the visual qualities. In addition, we extended the method to color halftoning and studied the impact of orientation information in different color channels on improving sharpness enhancement, preserving structural similarity, and decreasing color reproduction error. Furthermore, we propose a dynamic sharpness enhancement approach, which adaptively varies the local sharpness of the halftone image based on different textures across the image. Our contributions in the present work enable the algorithm to adaptively work on large images with multiple regions and different textures. (C) 2022 Society for Imaging Science and Technology.

  • 5.
    Abedini, Fereshteh
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Gooran, Sasan
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Kitanovski, Vlado
    Norwegian University of Science and Technology, Faculty of Information Technology and Electrical Engineering, Department of Computer Science, Gjøvik, Norway.
    Nyström, Daniel
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Structure-Aware Halftoning Using the Iterative Method Controlling the Dot Placement2021In: Journal of Imaging Science and Technology, ISSN 1062-3701, E-ISSN 1943-3522, Vol. 65, no 6Article in journal (Refereed)
    Abstract [en]

    Many image reproduction devices, such as printers, are limited to only a few numbers of printing inks. Halftoning, which is the process to convert a continuous-tone image into a binary one, is, therefore, an essential part of printing. An iterative halftoning method, called Iterative Halftoning Method Controlling the Dot Placement (IMCDP), which has already been studied by research scholars, generally results in halftones of good quality. In this paper, we propose a structure-based alternative to this algorithm that improves the halftone image quality in terms of sharpness, structural similarity, and tone preservation. By employing appropriate symmetrical and non-symmetrical Gaussian filters inside the proposed halftoning method, it is possible to adaptively change the degree of sharpening in different parts of the continuous-tone image. This is done by identifying a dominant line in the neighborhood of each pixel in the original image, utilizing the Hough Transform, and aligning the dots along the dominant line. The objective and subjective quality assessments verify that the proposed structure-based method not only results in sharper halftones, giving more three-dimensional impression, but also improves the structural similarity and tone preservation. The adaptive nature of the proposed halftoning method makes it an appropriate algorithm to be further developed to a 3D halftoning method, which could be adapted to different parts of a 3D object by exploiting both the structure of the images being mapped and the 3D geometrical structure of the underlying printed surface.

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  • 6.
    Abedini, Fereshteh
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Gooran, Sasan
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Nyström, Daniel
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    3D Halftoning based on Iterative Method Controlling Dot Placement2020Conference paper (Refereed)
    Abstract [en]

    Realistic appearance reproduction is of great importance in 3D printing’s applications. Halftoning as a necessary process in printing has a great impact on creating visually pleasant appearance. In this article, we study the aspects of adapting and applying Iterative Method Controlling Dot Placement (IMCDP) to halftone three-dimensional surfaces. Our main goal is to extend the 2D algorithm to a 3D halftoning approach with minor modifications. The results show high-quality reproduction for all gray tones. The 3D halftoning algorithm is not only free of undesirable artifacts, it also produces fully symmetric and wellformed halftone structures even in highlight and shadow regions.

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  • 7.
    Abedini, Fereshteh
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Gooran, Sasan
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Nyström, Daniel
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    The Effect of Halftoning on the Appearance of 3D Printed Surfaces2021Conference paper (Refereed)
    Abstract [en]

    Managing the final appearance of 3D surfaces is an interesting and essential topic in 3D printing applications. Knowledge about the parameters which influence the 3D surface reproduction quality enables engineers to achieve the final appearance as accurately as designed. Many studies have been conducted to explore numerous parameters that affect the quality of 3D surface reproduction. This work contributes to verifying the role of halftoning in increasing the 3D surface visual quality and the control over the surface appearance of a 3D printed object. The results show that applying different halftones according to the geometrical characteristics of the 3D surface could emphasize or diminish the perceived 3D geometrical structures of a shape. The experimental results are in line with the simulated outputs reported in previous work. Our findings might introduce a new approach towards having more control over 3D appearance reproduction without changing the material or printer settings.

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  • 8.
    Abrikosov, Alexei I.
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Masood, Talha Bin
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Falk, Martin
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Hotz, Ingrid
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Topological analysis of density fields: An evaluation of segmentation methods2021In: Computers & graphics, ISSN 0097-8493, E-ISSN 1873-7684, Vol. 98, p. 231-241Article in journal (Refereed)
    Abstract [en]

    Topological and geometric segmentation methods provide powerful concepts for detailed field analysis and visualization. However, when it comes to a quantitative analysis that requires highly accurate geometric segmentation, there is a large discrepancy between the promising theory and the available computational approaches. In this paper, we compare and evaluate various segmentation methods with the aim to identify and quantify the extent of these discrepancies. Thereby, we focus on an application from quantum chemistry: the analysis of electron density fields. It is a scalar quantity that can be experimentally measured or theoretically computed. In the evaluation we consider methods originating from the domain of quantum chemistry and computational topology. We apply the methods to the charge density of a set of crystals and molecules. Therefore, we segment the volumes into atomic regions and derive and compare quantitative measures such as total charge and dipole moments from these regions. As a result, we conclude that an accurate geometry determination can be crucial for correctly segmenting and analyzing a scalar field, here demonstrated on the electron density field.

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  • 9.
    Abrikosov, Alexei I.
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Veryazov, Valera
    Theoretical Chemistry, Lund University, Lund, Sweden.
    Multiscale Modelling of Atomistic Structure of Calcium Silicate Hydrate2022In: Solid State Phenomena, ISSN 1012-0394, E-ISSN 1662-9779, Solid State Phenomena, Vol. 338, p. 123-128Article in journal (Refereed)
    Abstract [en]

    The atomistic structure of calcium-silicate-hydrate (C-S-H) has been studied by applying force field simulations and quantum mechanical methods. Large number of crystallographically equivalent structures were used to account for the disordered nature of C-S-H. An extensive set of periodic structures of C-S-H (with a variation of chemical composition) has been generated and optimised. Special attention has been paid to two crystallographic models for tobermorite, which are used for the construction of C-S-H models. Re-optimisation of atomic structures, initially optimised with ReaxFF force field, by quantum chemical methods (semiempirical and Density functional theory) have been performed. Although the main structural characteristics of C-S-H remain the same in all calculations, the balance between the amount of OH groups and water in the structure is different. The obtained structures (optimised with a different level of theory) are combined into an on-line database and can be used for a future simulation of C-S-H materials.

  • 10.
    Abrikosov, Igor A.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics. Linköping University, Faculty of Science & Engineering.
    Alling, Björn
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Steneteg, Peter
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Hultberg, Lasse
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Hellman, Olle
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics. Linköping University, Faculty of Science & Engineering.
    Yu Mosyagin, Igor
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics. Linköping University, Faculty of Science & Engineering. Department of Theoretical Physics and Quantum Technologies, National Research, Technological University MISiS, Moscow, Russia.
    Lugovskoy, Andrey V.
    Department of Theoretical Physics and Quantum Technologies, National Research, Technological University MISiS, Russia.
    Barannikova, Svetlana A.
    Institute of Strength Physics and Materials Science, Siberian Branch of Russian Academy of Science, Tomsk, Russia; Department of Physics and Engineering, Tomsk State University, Tomsk, Russia.
    Finite Temperature, Magnetic, and Many-Body Effects in Ab Initio Simulations of Alloy Thermodynamics2013In: TMS2013 Supplemental Proceedings, John Wiley & Sons, 2013, p. 617-626Chapter in book (Refereed)
    Abstract [en]

    Ab initio electronic structure theory is known as a useful tool for prediction of materials properties. However, majority of simulations still deal with calculations in the framework of density functional theory with local or semi-local functionals carried out at zero temperature. We present new methodological solution.s, which go beyond this approach and explicitly take finite temperature, magnetic, and many-body effects into account. Considering Ti-based alloys, we discuss !imitations of the quasiharmonic approximation for the treatment of lattice vibrations, and present an accurate and easily extendable method to calculate free ,energies of strongly anharmonic solids. We underline the necessity to going beyond the state-of-the-art techniques for the determination of effective cluster interactions in systems exhibiting mctal-to-insulator transition, and describe a unified cluster expansion approach developed for this class of materials. Finally, we outline a first-principles method, disordered local moments molecular dynamics, for calculations of thermodynamic properties of magnetic alloys, like Cr1-x,.AlxN, in their high-temperature paramagnetic state. Our results unambiguously demonstrate importance of finite temperature effects in theoretical calculations ofthermodynamic properties ofmaterials.

  • 11.
    Abrikosov, Igor
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics. Linköping University, Faculty of Science & Engineering. National University of Science and Technology MISIS, Russia.
    Ponomareva, A. V.
    National University of Science and Technology MISIS, Russia.
    Steneteg, Peter
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Barannikova, S. A.
    National University of Science and Technology MISIS, Russia; National Research Tomsk State University, Russia; SB RAS, Russia.
    Alling, Björn
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Recent progress in simulations of the paramagnetic state of magnetic materials2016In: Current opinion in solid state & materials science, ISSN 1359-0286, E-ISSN 1879-0348, Vol. 20, no 2, p. 85-106Article, review/survey (Refereed)
    Abstract [en]

    We review recent developments in the field of first-principles simulations of magnetic materials above the magnetic order disorder transition temperature, focusing mainly on 3d-transition metals, their alloys and compounds. We review theoretical tools, which allow for a description of a system with local moments, which survive, but become disordered in the paramagnetic state, focusing on their advantages and limitations. We discuss applications of these theories for calculations of thermodynamic and mechanical properties of paramagnetic materials. The presented examples include, among others, simulations of phase stability of Fe, Fe-Cr and Fe-Mn alloys, formation energies of vacancies, substitutional and interstitial impurities, as well as their interactions in Fe, calculations of equations of state and elastic moduli for 3d-transition metal alloys and compounds, like CrN and steels. The examples underline the need for a proper treatment of magnetic disorder in these systems. (C) 2015 Elsevier Ltd. All rights reserved.

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  • 12.
    Adamsson, Christian
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Ho, Emilie
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Interactive 3D-visualization of a Solar Particle Event for Public Outreach2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This report presents the work of our Master´s thesis carried out remotely at the Community Coordinated Modeling Center at the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center. In collaboration with the American Museum of Natural History (AMNH), Linköping University and Predictive Science Inc. The report presents and evaluates an implementation of an interactive 3D visualization of a Solar Particle Event in OpenSpace, an open source astrovisualization software. Data from a model developed by Predictive Science Inc. was used to implement the visualization. The visualization is done by visualizing fluxes of particles as points and utilizing a volumetric data set by applying 2D textures to geometrical shapes. The goal of these visualizations is to help describe the effect of space weather phenomena to the general public. The research conducted is focused on how to visualize a big Solar Particle Event to emphasize or showcase different aspects, such as the radiation exposure close to Earth. The result of the work is an interactive real-time visualization of a Solar Particle Event designed for public outreach. The project culminated in two live streamed events with AMNH, in collaboration with NASA and Predictive Science Inc. 

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  • 13. Ahmad, Tausif
    et al.
    Gooran, Sasan
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Hybrid Color Halftoning2010Conference paper (Refereed)
  • 14.
    Ahmadian, Amirhossein
    et al.
    Linköping University, Department of Computer and Information Science, The Division of Statistics and Machine Learning. Linköping University, Faculty of Science & Engineering.
    Ding, Yifan
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Eilertsen, Gabriel
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Lindsten, Fredrik
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Department of Computer and Information Science, The Division of Statistics and Machine Learning. Linköping University, Faculty of Science & Engineering.
    Unsupervised Novelty Detection in Pretrained Representation Space with Locally Adapted Likelihood Ratio2024In: International Conference on Artificial Intelligence and Statistics 2024, Proceedings of Machine Learning Research, 2024Conference paper (Refereed)
  • 15.
    Ahmed, Hamad
    et al.
    Centre for Plasma Physics, Queen’s University of Belfast, Belfast BT7 1NN, UK.
    Doria, Domenico
    Centre for Plasma Physics, Queen’s University of Belfast, Belfast BT7 1NN, UK.
    Dieckmann, Mark Eric
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Sarri, Gianluca
    Centre for Plasma Physics, Queen’s University of Belfast, Belfast BT7 1NN, UK.
    Romagnani, Lorenzo
    LULI, École Polytechnique, CNRS, CEA, UPMC, Palaiseau, France.
    Bret, Antoine
    ETSI Industriales, Universidad Castilla La Mancha, E-13 071 Ciudad Real, Spain.
    Cerchez, M
    Institute for Laser and Plasma Physics, University of Düsseldorf, Germany.
    Giesecke, AL
    Institute for Laser and Plasma Physics, University of Düsseldorf, Germany.
    Ianni, E
    Centre for Plasma Physics, Queen’s University of Belfast, Belfast BT7 1NN, UK.
    Kar, Satya
    Centre for Plasma Physics, Queen’s University of Belfast, Belfast BT7 1NN, UK.
    Notley, Margaret
    Central Laser Facility, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX, UK.
    Prasad, R
    Centre for Plasma Physics, Queen’s University of Belfast, Belfast BT7 1NN, UK.
    Quinn, Kevin
    Centre for Plasma Physics, Queen’s University of Belfast, Belfast BT7 1NN, UK.
    Willi, Oswald
    Institute for Laser and Plasma Physics, University of Düsseldorf, Germany.
    Borghesi, Marco
    Centre for Plasma Physics, Queen’s University of Belfast, Belfast BT7 1NN, UK.
    Experimental Observation of Thin-shell Instability in a Collisionless Plasma2017In: Astrophysical Journal Letters, ISSN 2041-8205, E-ISSN 2041-8213, Vol. 834, no 2, article id L21Article in journal (Refereed)
    Abstract [en]

    We report on the experimental observation of the instability of a plasma shell, which formed during the expansion of a laser-ablated plasma into a rarefied ambient medium. By means of a proton radiography technique, the evolution of the instability is temporally and spatially resolved on a timescale much shorter than the hydrodynamic one. The density of the thin shell exceeds that of the surrounding plasma, which lets electrons diffuse outward. An ambipolar electric field grows on both sides of the thin shell that is antiparallel to the density gradient. Ripples in the thin shell result in a spatially varying balance between the thermal pressure force mediated by this field and the ram pressure force that is exerted on it by the inflowing plasma. This mismatch amplifies the ripples by the same mechanism that drives the hydrodynamic nonlinear thin-shell instability (NTSI). Our results thus constitute the first experimental verification that the NTSI can develop in colliding flows.

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  • 16.
    Aigner, Wolfgang
    et al.
    St Polten Univ Appl Sci, Austria.
    Enge, Kajetan
    St Polten Univ Appl Sci, Austria; Univ Mus & Performing Arts Graz, Austria.
    Iber, Michael
    St Polten Univ Appl Sci, Austria.
    Rind, Alexander
    St Polten Univ Appl Sci, Austria.
    Elmqvist, Niklas
    University of Maryland, College Park, United States.
    Hoeldrich, Robert
    Univ Mus & Performing Arts Graz, Austria.
    Rönnberg, Niklas
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering. Univ Maryland, DC USA.
    Walker, Bruce N.
    Georgia Inst Technol, GA USA.
    Workshop on Audio-Visual Analytics2022In: PROCEEDINGS OF THE WORKING CONFERENCE ON ADVANCED VISUAL INTERFACES AVI 2022, ASSOC COMPUTING MACHINERY , 2022Conference paper (Refereed)
    Abstract [en]

    In their daily lives, people use more than one sense to perceive and interpret their environment. Likewise, audio-visual interfaces can support human data analysts better than interfaces relying on just one sense. While the research communities of sonification and visualization have both carried out extensive research on the auditory and visual representation of data, comparatively little is known about their systematic and complementary combination for data analysis. After two workshops at Audio Mostly 2021 and IEEE VIS, this 3rd workshop on audio-visual analytics continues building a community of researchers interested in combining visualization and sonification.

  • 17.
    Aigner, Wolfgang
    et al.
    St. Pölten University of Applied Sciences, Austria.
    Enge, Kajetan
    St. Pölten University of Applied Sciences, Austria and University of Music and Performing Arts Graz, Austria.
    Iber, Michael
    St. Pölten University of Applied Sciences, Austria.
    Rind, Alexander
    St. Pölten University of Applied Sciences, Austria.
    Elmqvist, Niklas
    University of Maryland, College Park, United States.
    Höldrich, Robert
    University of Music and Performing Arts Graz, Austria.
    Rönnberg, Niklas
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Walker, Bruce N.
    Georgia Institute of Technology, United States.
    Workshop on Audio-Visual Analytics2022In: AVI 2022: Proceedings of the 2022 International Conference on Advanced Visual Interfaces, 2022Conference paper (Other academic)
    Abstract [en]

    In their daily lives, people use more than one sense to perceive and interpret their environment. Likewise, audio-visual interfaces can support human data analysts better than interfaces relying on just one sense. While the research communities of sonification and visualization have both carried out extensive research on the auditory and visual representation of data, comparatively little is known about their systematic and complementary combination for data analysis. After two workshops at Audio Mostly 2021 and IEEE VIS, this 3rd workshop on audio-visual analytics continues building a community of researchers interested in combining visualization and sonification.

  • 18.
    Akbaba, Derya
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Lange, Devin
    University of Utah, United States.
    Correll, Michael
    Tableau Research, Tableau Software, United States.
    Lex, Alexander
    University of Utah, United States.
    Meyer, Miriah
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Troubling Collaboration: Matters of Care for Visualization Design Study2023In: PROCEEDINGS OF THE 2023 CHI CONFERENCE ON HUMAN FACTORS IN COMPUTING SYSTEMS (CHI 2023), New York, NY, USA: Association for Computing Machinery (ACM), 2023Conference paper (Refereed)
    Abstract [en]

    A common research process in visualization is for visualization researchers to collaborate with domain experts to solve particular applied data problems. While there is existing guidance and expertise around how to structure collaborations to strengthen research contributions, there is comparatively little guidance on how to navigate the implications of, and power produced through the socio-technical entanglements of collaborations. In this paper, we qualitatively analyze reflective interviews of past participants of collaborations from multiple perspectives: visualization graduate students, visualization professors, and domain collaborators. We juxtapose the perspectives of these individuals, revealing tensions about the tools that are built and the relationships that are formed — a complex web of competing motivations. Through the lens of matters of care, we interpret this web, concluding with considerations that both trouble and necessitate reformation of current patterns around collaborative work in visualization design studies to promote more equitable, useful, and care-ful outcomes.

  • 19.
    Akbaba, Derya
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Meyer, Miriah
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    “Two Heads are Better than One”: Pair-Interviews for Visualization2023In: 2023 IEEE Visualization and Visual Analytics (VIS), Institute of Electrical and Electronics Engineers (IEEE), 2023Conference paper (Refereed)
    Abstract [en]

    Visualization research methods help us study how visualization systems are used in complex real-world scenarios. One such widely used method is the interview — researchers asking participants specific questions to enrich their understanding. In this work, we introduce the pair-interview technique as a method that relies on two interviewers with specific and delineated roles, instead of one. Pair-interviewing focuses on the mechanics of conducting semi-structured interviews as a pair, and complements other existing visualization interview techniques. Based on a synthesis of the experiences and reflections of researchers in four diverse studies who used pair-interviewing, we outline recommendations for when and how to use pair-interviewing within visualization research studies.

  • 20.
    Akkurt, Elin
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Folde, Johanna
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Visual Analysis of Humor Assessment in Edited News Headlines2023Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this project, we have focused on the Humicroedit data set which was created for one of the tasks presented during SemEval 2020. It contains the micro-edited versions of existing headlines where the aim was to make them funny. To analyze the edited headlines, various NLP techniques were applied, where the goal was to analyze the relationships and trends between the humor scores, sentiments, and topics of each data item. We have also considered the named entities and keywords, although to a lesser extent. This resulted in a visualization prototype that utilized the information visualization techniques treemap and dimensionality reduction. With the help of filtering and exploration features, an analysis could be performed on the data from the perspective of the different NLP modules. For this particular data set it was found that depending on the sentiment module, items of a certain score range and sentiment range will be grouped differently. It could also be determined that the sentiment value and the funniness score were highly dependent on the context of the edited headline. No certain connection could be made on how the topic affected the funniness score or the sentiment value due to the imbalanced distribution of topics in the Humicroedit data set. The prototype was evaluated by experts in NLP research and related fields. They deemed the prototype useful for its purpose and saw potential in exploring similar data sets with it, as well as reusing some of its features in their line of work.

  • 21.
    Akner-Kohler, Cheryl
    et al.
    Grythytte Academy, Örebro University, Sweden.
    Tibell, Lena
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Aesthetics and nanostructure2011In: International Innovation, ISSN 2041-4552, p. 97-99Article in journal (Other (popular science, discussion, etc.))
  • 22.
    Akram Hassan, Kahin
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    It’s About Time: User-centered Evaluation of Visual Representations for Temporal Data2021Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The primary goal for collecting and analyzing temporal data differs between individuals and their domain of expertise e.g., forecasting might be the goal in meteorology, anomaly detection might be the goal in finance. While the goal differs, one common denominator is the need for exploratory analysis of the temporal data, as this can aid the search for useful information. However, as temporal data can be challenging to understand and visualize, selecting appropriate visual representations for the domain and data at hand becomes a challenge. Moreover, many visual representations can show a single variable that changes over time, displaying multiple variables in a clear and easily accessible way is much harder, and inference-making and pattern recognition often require visualization of multiple variables. Additionally, as visualization aims to gain insight, it becomes crucial to investigate whether the representations used help users gain this insight. Furthermore, to create effective and efficient visual analysis tools, it is vital to understand the structure of the data, how this data can be represented, and have a clear understanding of the user needs. Developing useful visual representations can be challenging, but through close collaboration and involvement of end-users in the entire process, useful results can be accomplished. 

    This thesis aims to investigate the usability of different visual representations for different types of multivariate temporal data, users, and tasks. Five user studies have been conducted to investigate different representation spaces, layouts, and interaction methods for investigating representations’ ability to facilitate users when analyzing and exploring such temporal datasets. The first study investigated and evaluated the experience of different radial design ideas for finding and comparison tasks when presenting hourly data based on an analog clock metaphor. The second study investigated 2D and 3D parallel coordinates for pattern finding. In the third study, the usability of three linear visual representations for presenting indoor climate data was investigated with domain experts. The fourth study continued on the third study and developed and evaluated a visual analytics tool with different visual representations and interaction techniques with domain experts. Finally, in the fifth study, another visual analytics tool presenting visual representations of temporal data was developed and evaluated with domain experts working and conducting experiments in Antarctica. 

    The research conducted within the scope of this thesis concludes that it is vital to understand the characteristics of the temporal data and user needs for selecting the optimal representations. Without this knowledge, it becomes much harder to choose visual representations to help users gain insight from the data. It is also crucial to evaluate the perception and usability of the chosen visual representations. 

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  • 23.
    Akram Hassan, Kahin
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Rönnberg, Niklas
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Forsell, Camilla
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Johansson, Jimmy
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering. Linköping University, Centre for Climate Science and Policy Research, CSPR.
    On the Performance of Stereoscopic Versus Monoscopic 3D Parallel Coordinates2016Conference paper (Refereed)
    Abstract [en]

    This work presents the results from an evaluation of stereoscopic versus monoscopic 3D parallel coordinates. The objective of the evaluation was to investigate if stereopsis increases user performance. The results show that stereoscopy has no effect at all on user performance compared to monoscopy. This result is important when it comes to the potential use of stereopsis within the information visualization community.

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  • 24.
    Alberti, Marco
    et al.
    Dept. of Computer Science, Universidade Nova de Lisbona, Lisbon.
    Dell'Acqua, Pierangelo
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Pereira, Luis M
    Dept. of Computer Science, Nova Universidade de Lisboa, Lisbon.
    Observation Strategies for Event Detection with Incidence on Runtime Verification2010In: Experimental evaluation of algorithms for solving problems with combinatorial explosion / [ed] Marco Gavanelli and Toni Mancini, Bologna: Ceur , 2010Conference paper (Refereed)
  • 25.
    Alberti, Marco
    et al.
    Dept. of Computer Science, Nova Universidade de Lisboa, Lisbon.
    Dell'Acqua, Pierangelo
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Pereira, Luis M
    Dept. of Computer Science, Nova Universidade de Lisboa, Lisbon.
    Observation Strategies for Event Detection with Incidence on Runtime Verification: Theory, Algorithms, Experimentation2011In: Annals of Mathematics and Artificial Intelligence, ISSN 1012-2443, E-ISSN 1573-7470, Vol. 62, no 3-4, p. 161-186Article in journal (Refereed)
    Abstract [en]

    Many applications (such as system and user monitoring, runtime verification, diagnosis, observation-based decision making, intention recognition) all require to detect the occurrence of an event in a system, which entails the ability to observe the system. Observation can be costly, so it makes sense to try and reduce the number of observations, without losing full certainty about the event’s actual occurrence. In this paper, we propose a formalization of this problem. We formally show that, whenever the event to be detected follows a discrete spatial or temporal pattern, then it is possible to reduce the number of observations. We discuss exact and approximate algorithms to solve the problem, and provide an experimental evaluation of them. We apply the resulting algorithms to verification of linear temporal logics formulæ. Finally, we discuss possible generalizations and extensions, and, in particular, how event detection can benefit from logic programming techniques.

  • 26.
    Aldén, Fanny
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Juopperi, Emil
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    UX-verktyg för prototyputveckling med AI-baserat automationsstöd för omvandling av skisser till gränssnittskomponenter2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Att skapa prototyper för att testa idéer är vanligt, oavsett vad det är som ska testas. Prototyper kan förekomma i oändligt olika former och vara mer eller mindre verklighetstrogna. Hur verklighetstrogen en prototyp är beror på vad som ska testas och hur mycket tid som läggs på prototypskapandet. I teknikbranschen är prototyperna vanligen digitala och skapas med prototypprogram. Eftersom tid är pengar så försöker företag effektivisera prototyprocessen genom att utforska nya tekniker, som exempelvis artificiell intelligens. Syftet med examensarbetet som beskrivs i den här rapporten är att undersöka hur ett prototypverktyg med automation bör utformas samt vilka eventuella användningsområde verktyget har. Under examensarbetet genomfördes intervjuer med anställda på konsultföretaget Exsitec. Syftet med intervjuerna var att ta reda på hur Exsitec arbetar med prototyper i uppstarten av sina projekt. Med hjälp av informationen identifierades svårigheter i arbetsprocessen. Utifrån den informationen utvecklades prototypverktyget ProtoDraw. Verktyget är utrustat med artificiell intelligens, som känner igen skisser och ger utifrån dem rekommendationer på webbkomponenter. Prototypverktyget utvecklades, tränades och testades som en del av fallstudien. Målet med fallstudien var att testa användares förtroende för verktyget samt hur förtroendet berodde på verktygets automationsnivå. Prototypverktyget utrustades med tre automationsnivåer interaktionsmodell A, interaktionsmodell B och interaktionsmodell C. Interaktionsmodell A gav alla förslag till användaren och rekommenderade de mest lika komponenterna genom att rama in dem. I interaktionsmodell B fick användaren endast de tre bästa resultaten. I interaktionsmodell C fick användaren endast ett förslag från automationen. Totalt genomfördes 15 användartester, fem stycken på varje nivå. Resultatet från användartesterna visade att interaktionsmodell B hade högst och stadigast förtroende. Interaktionsmodell B var även nivån som användarna ansåg var mest användbar. Trots detta var A nivån som användarna utförde uppgifterna i användartesterna på kortast tid. C hade den långsammaste tiden och det berodde på att den höga automationsnivån bidrog till att gränssnittet blev känsligt för fel.

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  • 27.
    Alferes, José Julio
    et al.
    Centro de Inteligência Artificial - CENTRIA Departamento de Informática, Faculdade de Ciências e Tecnologia, Caparica, Portugal .
    Dell'Acqua, Pierangelo
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology. Centro de Inteligência Artificial - CENTRIA Departamento de Informática, Faculdade de Ciências e Tecnologia, Caparica, Portugal.
    Pereira, Luis Moniz
    Centro de Inteligência Artificial - CENTRIA Departamento de Informática, Faculdade de Ciências e Tecnologia, Caparica, Portugal.
    A compilation of updates plus preferences2002In: Logics in Artificial Intelligence 8th European Conference, JELIA 2002 Cosenza, Italy, September 23–26, 2002 Proceedings / [ed] Sergio Flesca, Sergio Greco, Giovambattista Ianni and Nicola Leone, Springer Berlin/Heidelberg, 2002, Vol. 2424, p. 62-74Chapter in book (Refereed)
    Abstract [en]

    We show how to compile programs formalizing update plus preference reasoning into standard generalized logic programs and show the correctness of the transformation.

  • 28.
    Algmark, Carl
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Eskilsson, Mattias
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Omgivningspåverkan vid sänkhammarborrning2014Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sänkhammarborrning är en metod som används för att utföra grundläggning med stålpålar. Metoden blir allt vanligare i Svenska tätbebyggda miljöer där krav ställs på låg omgivningspåverkan. Vid sänkhammarborrning borras ett foderrör av stål ner genom jordlagren till avsett djup, oftast till bärkraftigt berg. Foderröret lämnas sedan kvar, armeras, gjuts och utgör sedan själva pålen. Borrmaskinen består bland annat av en hammare som arbetar nere i hålet och drivs av antingen vatten eller luft. Borrföretagen har ofta tillgång till flera olika borrsystem men det saknas ibland underlag och forskning för hur olika borrsystem och metoder påverkar mark och omgivning vilket kan skapa en osäkerhet i projekteringsfasen och oförutsedda problem i utförandestadiet. Sänkhammarborrning anses ha en mindre massförträngande effekt men ger ändå en viss omgivningspåverkan både ovan och under mark. I den här studien har omgivningspåverkan under mark behandlats. Tre störningskällor har undersökts; vibrationer, uppspolning och trycksättning. Syftet har varit att teoretiskt undersöka hur vattendrivet- och luftdrivet sänkhammarborrsystem påverkar undergrunden i samband med att stålrörspålar installeras. För att nå syftet har en litteraturstudie och en intervjustudie genomförts. Även två fältbesök har gjorts. Litteratur och intervjuer har sedan analyserats med utgångspunkt i de tre nämnda fenomenen. Resultatet visar att de viktigaste faktorerna som påverkar hur stor omgivningspåverkan blir är markförutsättningar, maskinutrustning och utförandet. Vattendriven borrning visar sig löpa mindre risk att påverka omgivningen när det gäller uppspolning och trycksättning men om borrningen utförs på rätt sätt kan omgivningspåverkan undvikas även vid luftdriven borrning. De två borrsystemen har olika slagenergier och slagfrekvenser dock kan inga slutsatser dras av hur detta påverkar vibrationsnivåerna. Ett antal åtgärder finns för att minimera omgivningspåverkan, det handlar framförallt om att välja rätt borrsystem samt att borrningen utförs på rätt sätt.

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  • 29.
    Alm, Fei
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Brushing and Linking Primitive Evaluation of Hierarchical Data in Linked Visualizations2023Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The projects research focused on exploring techniques for visualizing and interacting with hierarchical data. It evaluated what are the most common practices for the exploration of hierarchical data and how it can further be designed using brushing and linking. The project was carried out at the Scientific Visualization unit at Linköping University. The work conducted a literature study and an evaluation using user tests. The evaluation is a pilot study where the visualizations, brushing techniques, dataset size, and conduction of the user test are based on a literature study. The study identified node-link diagrams, treemaps, and icicle plots as the most commonly used generic visualization techniques for exploring hierarchical data in research. Along with those visualizations, three brushing approaches linking different nodes to each other (based on different kinds of kinship) were applied in several combinations in prototypes, shown and used in the user tests. The results showed that coordinated multiple views with brushing and linking were frequently employed, allowing users to manipulate and interact with data on one screen while seeing relevant views updated. The study showed that treemaps are often struggling to visualize beyond leaf nodes and node-link diagrams become cluttered. The user study indicated that D-brushing (data brushed in descending directions) was preferred, and certain brushing methods were suitable depending on the task. Since the research is a pilot study, it is recommended to perform additional studies such as further designing brushing to provide a guideline for user freedom in highlighting relationships, and in linked views. Some design suggestions that are worth studying and testing in further work are, for example, using color maps to show the hierarchical attributes and relationships between nodes while brushing, re-layouts of text labels, and ordering nodes alphabetically

  • 30.
    Almer, Lili
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Bodin, Jennifer
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Objektifiering av kvinnor på sociala medier - Var går gränsen?: En studie om unga mäns förhållningssätt till kvinnoobjektifierande bilder på sociala medier2021Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [sv]

    Sociala medier är ett fenomen som växer världen över och är något som de flesta unga använder dagligen. Genom att använda olika plattformar dagligen medföljer positiva och negativa konsekvenser, bland annat att påverkas av det man exponeras för på olika sätt. Kvinnoobjektifiering på sociala medier är ett ämne som uppmärksammats mer på senare år och kan anses vara problematiskt, men det är svårt att säga var gränsen går för vad som är acceptabelt. Denna studie syftar därför till att undersöka hur unga män förhåller sig till kvinnoobjektifiering på sociala medier, vad de anser vara acceptabelt och inte, samt hur de kan påverkas av materialet. Forskningsfrågorna har besvarats med hjälp av intervjuer, teorier inom bildanalys, tematisk analys och stöd i form av litteratur som använts för att analysera materialet. Studien har en kvalitativ ansats och undersökningen är genomförd med sex semistrukturerade intervjuer med unga män i åldrarna 20-25 år. En enkät som inledande studie har legat till grund för arbetet och haft inflytande på studiens syfte samt intervjuerna. En tematisk analys av kvalitativa intervjuer påvisar unga mäns syn på kvinnoobjektifierande material i sociala medier och hur de förhåller sig till det: unga män anser det vara nedvärderande och förminskande men finner ett dilemma i censurering av materialet. Vissa tror att censur på sociala medier är en bra lösning, när andra tvivlar på att det skulle lösa problemet och istället inskränka på yttrandefriheten. Analys av litteratur påvisar att kvinnoobjektifiering på sociala medier kan påverka unga män på olika sätt. Ett av dessa sätt är att de kan få en sämre kvinnosyn och normalisera ett kvinnoobjektifierande beteende, vilket kan leda till negativa konsekvenser för både kvinnor och män. Slutsatsen är att negativa konsekvenser förekommer av materialet och att censur skulle kunna motverka dem - om sociala medier är villiga att prioritera det.

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  • 31.
    Almlöf, Mattias
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Stockidentifiering och estimering av diameterfördelning med djupinlärning2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Mabema har en produkt som mäter vedvolym av virkestravar på lastbilar. Systemet är byggt på att en bildbehandlingsalgoritm hittar silhuetterna av stockarna på renderade bilder av lastbilstravar. Arbetsgivaren är inte helt nöjd med prestandan av algoritmen och vill utreda om djupinlärning kan förbättra resultatet. Detta arbete undersöker hur diameterfördelningen i varje trave kan estimeras med hjälp av djupinlärning och objektdetektering i synnerhet. Två metoder granskas, den ena hanterar problemet abstrakt med djup regression medan den andra metoden går in i detalj och nyttjar objektigenkänning för att hitta stockändar. Arbetet utvärderar även möjliheterna att träna dessa modeller baserat på data från fysiska simulationer. Det visar sig vara användbart att nyttja syntetisk data för träning och med transfer learning lyckas de syntetiska modellen uppnå kraven Biometria ställer på automatiserad diameterberäkning. Med objektdetektering visar det sig också gå att uppnå samma prestanda som arbetsgivarens algoritm med en bättre stocksökning tre gånger så snabbt eller snabbare.

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  • 32.
    Almqvist, Ellen
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Ekbladh, Mathilda
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Hur en flergångskasse kan utformas för att stimulera till köp och användning2022Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The manufacture and consumption of plastic is one of the world's biggest environmental culprits. In 2020, the Swedish government introduced an increased tax on plastic carrier bags to reduce the use of plastic. The increase has resulted in a higher price for plastic carrier bags, which motivates the consumer to use reusable bags instead. The purpose of this study was thus to investigate, from a sustainable perspective, how a reusable bag can be designed to increase purchase intention; the desire to buy a reusable bag, as well as increase use; that the reusable bag is used for several purposes and many times.In order to, through design, produce an optimal reusable bag, both product design and graphic design were examined. In the initial study, the target group's behavior around the use of reusable bags was examined. The initial study laid a foundation for how the bag would be designed and therefore goals were formulated based on the initial study's results and analysis. The goals have served as a starting point for concept generation and evaluation of the design. The design alternatives were evaluated partly through user testing of three prototypes of the bag’s function and product design, and partly through a survey where three graphic design concepts were presented. From the evaluation, the study received answers on how a reusable bag is designed to stimulate use and purchase.After evaluating the various design options for both product design and graphic design, a final design could be determined. The result for the product design was a bag in a square shape with a rectangular bottom, in organic cotton with a larger water resistant inner pocket and an outer pocket for a water bottle, for example. To appeal to the target group with the bag's graphic design, childhood characters were used as a tool, and the final design landed in an image of the literary figure Babar.

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  • 33.
    Alqaysi, Hiba
    et al.
    Department of Electronics Design, Mid Sweden University, Sweden.
    Fedorov, Igor
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Qureshi, Faisal Z
    Faculty of Science, University of Ontario Institute of Technology, Oshawa, Canada.
    ONils, Mattias
    Department of Electronics Design, Mid Sweden University, Sundsvall, Sweden.
    A Temporal Boosted YOLO-Based Model for Birds Detection around Wind Farms2021In: Journal of imaging, ISSN 2313-433X, Vol. 7, no 11, article id 277Article in journal (Refereed)
    Abstract [en]

    Object detection for sky surveillance is a challenging problem due to having small objects in a large volume and a constantly changing background which requires high resolution frames. For example, detecting flying birds in wind farms to prevent their collision with the wind turbines. This paper proposes a YOLOv4-based ensemble model for bird detection in grayscale videos captured around wind turbines in wind farms. In order to tackle this problem, we introduce two datasets-(1) Klim and (2) Skagen-collected at two locations in Denmark. We use Klim training set to train three increasingly capable YOLOv4 based models. Model 1 uses YOLOv4 trained on the Klim dataset, Model 2 introduces tiling to improve small bird detection, and the last model uses tiling and temporal stacking and achieves the best mAP values on both Klim and Skagen datasets. We used this model to set up an ensemble detector, which further improves mAP values on both datasets. The three models achieve testing mAP values of 82%, 88%, and 90% on the Klim dataset. mAP values for Model 1 and Model 3 on the Skagen dataset are 60% and 92%. Improving object detection accuracy could mitigate birds mortality rate by choosing the locations for such establishment and the turbines location. It can also be used to improve the collision avoidance systems used in wind energy facilities.

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  • 34.
    Al-Sader, Mohamed
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Gaze-driven interaction in video games2018Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The introduction of input devices with natural user interfaces in gaming hardware has changed the way we interact with games. Hardware with motion-sensing and gesture recognizing capabilities remove the constraint of interacting with games through typical traditional devices like mouse-keyboard and gamepads. This changes the way we approach games and how the game communicates back to us as the player opening new levels of interactivity. This thesis covers how eye tracker technology can be used to affect rendering effects in games.

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    Gaze-driven interaction in video games
  • 35.
    Alsegård, Adam
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Interactive out-of-core rendering and filtering of one billion stars measured by the ESA Gaia mission2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis was to visualize the 1.7 billion stars released by the European Space Agency, as the second data release (DR2) of their Gaia mission, in the open source software OpenSpace with interactive framerates and also to be able to filter the data in real-time. An additional implementation goal was to streamline the data pipeline so that astronomers could use OpenSpace as a visualization tool in their research.

    An out-of-core rendering technique has been implemented where the data is streamed from disk during runtime. To be able to stream the data it first has to be read, sorted into an octree structure and then stored as binary files in a preprocess. The results of this report show that the entire DR2 dataset can be read from multiple files in a folder and stored as binary values in about seven hours. This step determines what values the user will be able to filter by and only has to be done once for a specific dataset. Then an octree can be created in about 5 to 60 minutes where the user can define if the stars should be filtered by any of the previously stored values. Only values used in the rendering will be stored in the octree. If the created octree can fit in the computer’s working memory then the entire octree will be loaded asynchronously on start-up otherwise only a binary file with the structure of the octree will be read during start-up while the actual star data will be streamed from disk during runtime.

    When the data have been loaded it is streamed to the GPU. Only stars that are visible are uploaded and the application also keeps track of which nodes that already have been uploaded to eliminate redundant updates. The inner nodes of the octree store the brightest stars in all its descendants as a level-of-detail cache that can be used when the nodes are small enough in screen space.

    The previous star rendering in OpenSpace has been improved by dividing the rendering phase into two passes. The first pass renders into a framebuffer object while the second pass then performs a tonemapping of the values. The rendering can be done either with billboard instancing or point splatting. The latter is generally the faster alternative. The user can also switch between using VBOs or SSBOs when updating the buffers. The latter is faster but requires OpenGL 4.3, which Apple products do not currently support.

    The rendering runs with interactive framerates for both flat and curved screen, such as domes/planetariums. The user can also switch dataset during render as well as render technique, buffer objects, color settings and many other properties. It is also possible to turn time on and see the stars move with their calculated space velocity, or transverse velocity if the star lacks radial velocity measurements. The calculations omits the gravitational rotation. The purpose of the thesis has been fulfilled as it is possible to fly through the entire DR2 dataset on a moderate desktop computer and filter the data in real-time. However, the main contribution of the project may be that the ground work has been laid in OpenSpace for astronomers to actually use it as a tool when visualizing their own datasets and also for continuing to explore the coming Gaia releases.

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    Interactive out-of-core rendering and filtering of one billion stars measured by the ESA Gaia mission
  • 36.
    Altarriba Bertran, Ferran
    et al.
    University of California, Santa Cruz, Santa Cruz, CA, USA.
    Börütecene, Ahmet
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Turan Buruk, Oguz
    Tampere University, Tampere, Finland.
    Thibault, Mattia
    Tampere University, Tampere, Finland.
    Isbister, Katherine
    University of California, Santa Cruz, Santa Cruz, CA, USA.
    MESMER: Towards a Playful Tangible Tool for Non-Verbal Multi-Stakeholder Conversations2020Conference paper (Refereed)
    Abstract [en]

    In this paper we present MESMER, a work-in-progress tangible conversation tool for playful design. Our work extends the Otherworld Framework (OF) [7] for tangible tools by centering specifically on play as a conversation topic. Here we unpack how early experiments with OF motivated our work and describe the current iteration of the MESMER tool, which comprises persona cards, various boards, and a shared physical token. MESMER is inspired by our findings from early trials with OF: performative playful interaction promoted playful and divergent thinking; embodied non-verbal communication led to shared insights, the board's contents and structure helped scaffold conversations, a diversity of personas and narratives seemed desirable, and role-playing personas encouraged multi-stakeholder empathy. Our ongoing research aims to help designers and researchers to facilitate engaging, fruitful and inspiring conversations where diverse stakeholders can contribute to playful technology design.

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    fulltext
  • 37.
    Alvberg, Amanda
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    En bild säger mer än tusen ord: En kvalitativ studie om vad som väcker konsumenters intresse på Instagram2022Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Social media is a growing phenomenon that is becoming more prevalent around the world. One of the most widely used platforms is Instagram, where people can share their everyday lives through photos, and where companies can spread their brand through visual communication. Today, it is more challenging than ever for companies to stand out with their message in a market that is becoming increasingly saturated, and it is important for companies to differentiate themselves from competitors. One of the many industries that is affected by this is the interior design industry, where the visual elements are an important piece of the puzzle to successfully inspire and attract new and existing consumers in a digital market. This study therefore investigates which visual elements in interior design images from interior design companies on the platform Instagram, targeting a customer group from Scandinavia and the Nordics, that consumers experience as most appealing. The study also investigates in where they create the most interest among consumers and how these visual elements can be used in practice. The aim of the study is to investigate which visual elements in interior design images published by the interior design companies Ellos, Rum21, Hemtex and Royal Design, that is the most appealing to the selected target group of women aged 19-30 years, what the visual language of these companies looks like and whether the companies' intentions match what the selected target group finds appealing. To answer this question, theories of semiotics, visual rhetoric, digital marketing, visual communication, and identity are used.The study has a qualitative approach and has been carried out trough analysis of four different interior images, where one post per company has been selected. The study has also been conducted with five semi-structured interviews with the target group of women aged 19-30 years. An initial survey was carried out and formed the basis for the rest of the work. Analysis of the selected visual material together with the thematic analysis of the semi-structured interviews shows that the main visual elements of interior design images that appeal to and arouse the most interest in the selected target group, are the color scale, the light in the image, the photographic angle, and the choice of materials. These visual elements greatly influence the associations and experiences for the consumers, which in turn contribute to the emotion conveyed by the image. These should be used and implemented in the right way to appeal, where the study shows that the visual language of companies is to some extent consistent with what appeals to the target audience in a visual communication. The missing aspect lies in the fact that interior design companies do not always have enough insight into what consumers will associate and feel about the chosen visual elements, as well as the chosen context. As a result, consumers' experience of the image does not reflect the feeling that the companies intend to convey. This further leads to the visual elements confusing the message rather than reinforcing it. By using the above-mentioned visual elements in the right way, in combination with each other, interior design companies can stand out from the crowd where they manage to appeal to and inspire the consumer through their interior design images.

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  • 38.
    Alverby, Emilia
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Linder, Elin
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Barns exponering i betalda samarbeten på Instagram: En kvalitativ studie om hur influencers exponerar sina barn i betalda samarbeten och hur instagramanvändare upplever dessa bilder2022Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Influencers are a large part of the social media world, which has given motive to influencer marketing where influencers market products through paid collaborations with companies. In some of these paid collaborations children are shown, because Swedish influencers include their children in the content they publish on social media. The purpose of the study is to examine, from a visual point of view, how Swedish influencers portray their children in paid collaborations, as well as how female Instagram users in the age group 18-30 years experience images in which children participate.With a qualitative approach, the study was conducted with the help of six semi-structured interviews and an image analysis supported by theories. A pilot study in the form of a questionnaire survey has served as a basis for the study's delimitations and recruitment of respondents. Moreover, it has also worked as support for the interview guide. The result of the analysis shows that children are portrayed in relation to their parent, where the child interacts with the marketed product while sitting down. Children's facial expressions vary from happy to confused, also both ethos and pathos are consistently rhetorical tools used in the portraying of children in paid collaborations. Female instagram users, between the ages of 18-30 years old, have mixed experience of images where children are exposed in paid collaborations. The experience is mainly affected by how the children are portrayed in the picture, but the experience can also vary depending on the composition of the image. Important components for how the target group experiences these types of images are the following; the environment in which the child is shown, the child's facial expression and character, if there is an activity in the image, who the influencer is and which product is marketed, as well as ethical aspects. Images with more natural elements in form of environment, character, and positive emotions through facial expressions are experienced as more genuine, natural and wonderful.

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  • 39.
    Ambrosini, Lorenzo
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Data Bricks Space Mission: Supporting Teachers for Children's Data Literacy in Primary Schools through Data Physicalization2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis presents "Data bricks space mission" a toolkit for children that allows them to gather a dataset of information in an engaging and interesting way. The kit is made up of elements that give the opportunity of a first approach to the data physicalization process, breaking down barriers related to knowledge and experience in the field. The experience is completed by a guided activity that, through a role play, inserts the the-me of the data collection in the school curriculum.

    The study is based on the analysis of similar previous examples and the collection of information through interviews with instructors who work daily with children. Based on the insights of those theoretical and empirical foundations, a possible solution is presented that addresses the research questions.

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  • 40.
    Ambrosini, Lorenzo
    et al.
    Linköping University.
    Meyer, Miriah
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Data Bricks Space Mission: Teaching Kids about Data with Physicalization2022In: 2022 IEEE Workshop on Visualization for Social Good (VIS4Good), 2022Conference paper (Refereed)
    Abstract [en]

    The Data Bricks Space Mission is a prototype activity based on data physicalization for teaching kids about data. The design of the activity is based on a literature review and interviews with elementary school teachers, and targets kids aged 10-12. Using Lego bricks and a fictional space adventure story, teachers can use the Data Bricks Space Mission activity to empower kids to produce data, communicate their findings, and gain a better understanding of the relationship between data and the world around them.

  • 41.
    Anaby, Dana
    et al.
    School of Physical and Occupational Therapy, McGill University, Montreal, Canada.
    Vrotsou, Katerina
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Kroksmark, Ulla
    Sahlgrenska Academy, Institute of Neuroscience and Physiology, University of Gothenburg, Göteburg, Sweden.
    Ellegård, Kajsa
    Linköping University, Department of Thematic Studies, Technology and Social Change. Linköping University, Faculty of Arts and Sciences.
    Changes in participation patterns of youth with physical disabilities following the Pathways and Resources for Engagement and Participation intervention: A time-geography approach2020In: Scandinavian Journal of Occupational Therapy, ISSN 1103-8128, E-ISSN 1651-2014, Vol. 27, no 5, p. 364-372Article in journal (Refereed)
    Abstract [en]

    Background: The PREP (Pathways and Resources for Engagement and Participation), an innovative 12-week occupational therapy intervention that focuses on changing the environment, was found effective in improving the participation of youth in specific chosen community-based activities.

    Objective: To complement existing evidence, this study explored changes in overall participation patterns of youth with physical disabilities following the PREP intervention.

    Methods: Guided by time-geography approach, 13 youth aged 12–17 completed a 24-hr diary using the Aday app during one typical weekday and another day during the weekend, pre- and post-intervention. Data of 50 diaries were plotted and analyzed using the VISUALTimePAcTS program.

    Results: Following the PREP, youth were engaged in less digital media and more in study-related activities. Number of occurrences and time spent doing activities with friends were greater post-intervention, whereas time spent doing activities at home was quite similar, particularly during the weekdays. During the weekends, however, youth spent slightly less time at home.

    Conclusions and significance: Findings provide preliminary support for the effectiveness of the PREP, extending beyond the accomplishment of specific targeted activities towards a change in the overall daily patterns of youth. Such knowledge can redirect occupational therapists’ attention to environment-focused interventions involving real-life experiences.

  • 42.
    Ander, Julia
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Coating actions for an intersection affected by repeated rutting.2013Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Korsningar, busshållplatser, söderbackar och lastkajer är ytor med extrem påkänning på grund av hög trafikbelastning, låg hastighet, accelerationer, inbromsningar, svängningar, spårbundenhet och utsatthet för höga temperaturer. Den speciella lastsituationen riskerar orsaka spårbildning, vilket är det vanligaste problemet i korsningar. Genom att anpassa beläggningen efter den utsatta ytan så kan projektören påverka vägens funktion och livslängd. Syftet med detta examensarbete var att studera vilka beläggningsåtgärder som är lämpliga för utsatta körytor såsom korsningar och busshållplatser samt att se vad som orsakar skadebilden i en skadedrabbad korsning. Vidare var syftet att jämföra tre beläggningsalternativ för att se vilket som var mest fördelaktigt ur ett livslängds- och kostnadsperspektiv. Frågeställningarna var följande: 1. Vilka beläggningar är lämpliga för särskilt utsatta körytor såsom korsningar och busshållplatser? 2. Vad orsakar skadebilden vid frånfarten på Malmslättsvägen vid korsningen Malmslättsvägen/ Kaserngatan? 3. Vilken beläggningsåtgärd av ABS11, Densiphalt och PMA är bäst ur ett livslängd- och kostnadsperspektiv under 20 år för korsningen Malmslättsvägen/ Kaserngatan? För att besvara frågeställningarna gjordes litteraturstudier samt en fallstudie i form av okulär bedömning och balkanalys i det aktuella vägsnittet. Dessutom jämfördes livslängd och kostnader mellan beläggningsalternativen i PMS Objekt respektive genom en ekonomisk beräkningsmetod. Resultatet visade att ett bindlager kan uppta de skjuvkrafter som uppstår på utsatta ytor och förhindrar därmed sprickbildning och deformationer. CBÖ och platsgjuten betong har i studier visat begränsa spårbildning. Densiphalt är lämplig som beläggning på utsatta ytor och ger samtidigt ytan motståndskraft mot olja och bensin. IM är starkare, styvare och mindre deformationsbenägen än en vanlig asfalt och är därför lämplig på högtrafikerade vägar. Fallstudien på det aktuella vägsnittet visade att skadebilden hade två orsaker. Dels fanns ett ytslitage som var orsakat av den spårbundna dubbdäckstrafiken. Dessutom förekom plastisk deformation i det andra och tredje asfaltlagret till följd av otillräcklig stabilitet i asfaltmassan med hänsyn till den långsamtgående och stillastående trafiken. De obundna lagren var till synes opåverkade vid balkanalysen. Jämförelsen mellan beläggningsalternativen visade att Densiphalt hade längst livslängd följt av PMA och ABS11. Kostnadsmässigt hade PMA lägst annuitet följt av Densiphalt och ABS11. Orsaken till att ABS11 var dyrast var troligen behovet av mellanliggande akutåtgärder i form av gjutasfalt. Slutsatsen var att kompletterande bindlager, CBÖ, PMA, Densiphalt, betong och IM var lämpliga beläggningar för särskilt utsatta ytor. Skadebilden vid det undersökta vägsnittet bedömdes bero på ytslitage på grund av spårbunden dubbdäckstrafik samt plastisk deformation till följd av tung trafik. Densiphalt hade längst livslängd och PMA hade lägst annuitet. Konventionell ABS11 var sämst ur både livslängds- och kostnadsperspektiv, vilket bedömdes bero på behovet av mellanliggande akutåtgärder i form av gjutasfalt.

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  • 43.
    Anderson, Camilla
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Andersson, Frida
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Subscribers loyalty for newspapers - a study of Östgöta Correspondentens weekend supplement2015Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Upplagesiffrorna för den tryckta dagstidningen har minskat under flera år. I Sverige är det ett stort problem då prenumerationen av den tryckta dagstidningen fortfarande är tidningsföretagens största inkomstkälla. Detta gör att det är av stor vikt för tidningsföretagen att hitta ett sätt att behålla dessa kunder. I denna studie har det undersökts om utformningen av en bilaga kan bidra till att prenumeranterna blir mer lojala. Studien har utförts i sammanbete med Östgöta Correspondenten och dess helgbilaga Paus Weekend. För att svara på syftet delades studien upp i två delproblem: vad har Östgöta Correspondentens nuvarande prenumeranter för attityder till Paus Weekend och huvudtidningen samt om det finns andra liknande bliagor som uppnått ökad kundlojalitet.

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  • 44.
    Anderson, Trevor
    et al.
    Purdue University, USA.
    Schönborn, Konrad
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    du Plessis, Lynn
    University of KwaZulu-Natal, South Africa.
    Gupthar, Abindra
    University of KwaZulu-Natal, South Africa.
    Hull, Tracy
    University of KwaZulu-Natal, South Africa.
    Identifying and Developing Students' Ability to Reason with Concepts and Representations in Biology2013In: Multiple Representations in Biological Education / [ed] D.F. Treagust and C.-Y. Tsui, Springer Science+Business Media B.V., 2013, p. -390Chapter in book (Refereed)
    Abstract [en]

    This new publication in the Models and Modeling in Science Education series synthesizes a wealth of international research on using multiple representations in biology education and aims for a coherent framework in using them to improve higher-order learning. Addressing a major gap in the literature, the volume proposes a theoretical model for advancing biology educators’ notions of how multiple external representations (MERs) such as analogies, metaphors and visualizations can best be harnessed for improving teaching and learning in biology at all pedagogical levels.The content tackles the conceptual and linguistic difficulties of learning biology at each level—macro, micro, sub-micro, and symbolic, illustrating how MERs can be used in teaching across these levels and in various combinations, as well as in differing contexts and topic areas. The strategies outlined will help students’ reasoning and problem-solving skills, enhance their ability to construct mental models and internal representations, and, ultimately, will assist in increasing public understanding of biology-related issues, a key goal in today’s world of pressing concerns over societal problems about food, environment, energy, and health. The book concludes by highlighting important aspects of research in biological education in the post-genomic, information age. 

  • 45.
    Andersson, Adrian
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Paulsson, Joel
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Interactive Visualization of Air Traffic in OpenSpace2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis report presents a master’s thesis project in Media Technology by two students from Linköping University, Sweden. The project was implemented in collaboration with the Visualization Center C and Linköping University during the spring of 2021 resulting in the creation and development of two spatiotemporal visualizations featuring air traffic data in the OPENSPACE software. One visualization uses live, real-time, data provided by The OpenSky Network through a Representational State Transfer Application Program-ming Interface (REST API). The other visualization uses a static historical data set covering aviation data during the COVID-19 pandemic that is mined from The OpenSky Network. A major challenge during the implementation was handling the large amount of data in a performant manner to avoid a reduced frame rate in the application. To solve this a mul-tithreaded method is used in order to not interrupt the rendering while new data are be-ing fetched to memory. OPENSPACE uses the Application Programming Interface (API) OpenGL to render graphics, thus also enabling a shader pipeline to be utilized. Multiple shaders are used to create the visualizations. The shaders’ purpose and implementation are explained in detail for both visualizations.

    The live data visualization features aircraft displayed by an anti-aliased trail of past po-sitions while the historical data visualization animates pathlines that represents aircraft with respect to time. The historical data visualization uses multiple Vertex Buffer Objects (VBOs) to render data efficiently and without interruption to allow the animation to play both forward and in reverse. The animation follows the time, time direction, and the speed of which the time plays set by the user in OPENSPACE to play seamlessly. The color of the pathlines are determined by continent to create a clustering effect without any pre-processing or calculations on the Central Processing Unit (CPU). Furthermore, the data can be filtered rapidly and in real-time by using Graphical User Interface (GUI) elements to control the filtering and by performing the actual filtering on the Graphics Processing Unit (GPU). The two visualizations enables user settings via their respective GUI. These settings include changing the color, opacity, and line width to aid in exploration of the data.

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  • 46.
    Andersson, Annika
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Björndahl, Caroline
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Säsongssmart - Att kommunicera mat i säsong2017Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [sv]

    Forskare har länge pekat på hur vår livsstil inte är hållbar ur ett miljömässigt perspektiv vilket har bidragit till en ökad efterfrågan av ekologiska alternativ och livsmedel som följer den naturliga säsongen i Sverige. Många konsumenter har dock svårt att veta när olika råvaror är i säsong för tillfället. Studien ämnar därför att undersöka hur och var kommunikation kan utformas och kommuniceras för att förmedla fördelarna med att konsumera mat efter säsong samt vilken mat som är i säsong för tillfället i Sverige.

    För att besvara syftet med studien har forskning genom design använts, vilket resulterade i de två koncepten Reko och Grönt tar ordet. Båda koncepten kommunicerar fördelarna med att konsumera mat efter säsong och när dess naturliga säsong infaller. Koncepten konstaterades i värderingen framgångsrika och skapade önskade associationer hos målgruppen. Konceptet Grönt tar ordet upplevdes humoristisk och konceptet Reko upplevdes enkelt, vilket ansågs som framgångsrika och lyckade sätt att tilltala målgruppen.

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    Clever consuming - How to communicate seasonal food
  • 47.
    Andersson, Fanny
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Furugård, Anna
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Detektion och klassificering av äppelmognad i hyperspektrala bilder2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Detta arbete presenterar en icke-destruktiv metod för att detektera och klassificera mognadsgraden hos äpplen med användning av hyperspektrala bilder. Fastställning av mognadsgraden hos äpplen är intressant för bland annat äppelodlare och musterier vid lagring och beredning. Äpplens mognadsgrad är även intressant inom växtförädling. För att fastställa mognadsgraden idag krävs att det skärs i frukten, en så kallad destruktiv metod. Hyperspektrala bilder kan idag användas inom områden som jordbruk, miljöövervakning och militär spaning.

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  • 48.
    Andersson, Frida
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Östfelt, Julia
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Beyond ideals of beauty2023Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
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  • 49.
    Andersson Granberg, Tobias
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering. CARER.
    Granlund, Rego
    SICS East Swedish ICT AB, Sweden.
    Lindborg, Jonas
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Ulander, Anna
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering. CARER.
    Dynamisk planering av räddningstjänst2014Report (Other academic)
    Abstract [sv]

    Dynamisk planering innebär bland annat att brandmännen delar in sig i mindre grupper än traditionellt. Dessa kan då arbeta förebyggande med utbildning eller placeras strategiskt till exempel i närheten av olycksdrabbade vägsträckor, för att snabbare kunna nå fram till en olycksplats. Då en olycka inträffar larmas de brandmän som snabbast kan nå fram, och det kan vara nödvändigt att larma flera olika grupper.

    En utmaning vid dynamisk planering är att planeringssituationen blir svårare. Det är inte längre självklart vilka brandmän som ska larmas till en viss olycka. Det kan också vara svårt att hitta de bästa placeringarna för brandmän som snabbt ska kunna göra en insats.

    I projektet har vi utvecklat och utvärderat datorbaserade verktyg som kan stödja dynamisk planering av räddningstjänst.

    Bland verktygen finns en beredskapskalkylator med tillhörande visualisering, vilken beräknar beredskapen som en funktion av tiden det tar för de nödvändiga resurserna att nå fram till en viss typ av olycka och sannolikheten för att olyckan ska inträffa i närområdet. Ett annat verktyg kan ge förslag på vilka resurser som bör skickas till en olycksplats för att de ska komma fram så fort som möjligt. Ett tredje verktyg kan ge förslag på hur fordon och personal dynamiskt bör placeras för att beredskapen ska förbättras, dvs. de ska kunna nå fram så fort som möjligt till de platser där det är störst sannolikhet att en olycka kommer att inträffa.

    Verktygen har utvärderats genom två experimentserier. I experimenten testades mänskligt beslutsfattande i en simulerad räddningstjänstmiljö. I den första serien fick personal från olika räddningstjänster prova på dynamisk planering utan hjälp av de datorbaserade verktygen. I den andra serien fick andra räddningstjänster köra samma scenarier, men då ta hjälp av de i projektet utvecklade verktygen.

    Resultaten visar att verktygen kan hjälpa räddningstjänsten med planeringen av beredskapen, men också att det finns risk att detta sker på bekostnad av att planeringen tar något längre tid. En tydlig majoritet av de deltagande räddningstjänstbefälen var positivt inställda till de utvecklade verktygen och tyckte verktyg av detta slag skulle kunna hjälpa dem i det dagliga arbetet.

    Resultaten tydliggör också att olika personer – till och med nära kollegor inom samma räddningstjänst – uppfattar begreppet beredskap på olika sätt. Det visade sig dock att beredskapsvisualiseringen kan bidra till att denna skillnad i uppfattning minskar; i den andra experimentserien, där de hade tillgång till detta verktyg, minskade variationerna i bedömningarna och deltagarnas uppfattningar stämde bättre överens med den beräknade beredskapen.

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  • 50.
    Andersson Granberg, Tobias
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Lundberg, Jonas
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Ulander, Anna
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Rego, Granlund
    SICS Swedish ICT, Linkoping, Sweden.
    Supporting dispatch decisions for the fire and rescue services2015In: 2015 IEEE 18th International Conference on Intelligent Transportation Systems, IEEE conference proceedings, 2015, p. 2562-2567Conference paper (Refereed)
    Abstract [en]

    Decision support tools for efficient dispatching of fire and rescue resources are developed and evaluated. The tools can give suggestions about which resources to dispatch to new accidents, and help the decision makers in evaluating the current preparedness for handling future accidents. The tools are evaluated using simulation game based experiments, with players from the fire and rescue services. The results indicate that the tools can help the fire and rescue services in identifying the closest resources to new accidents, and to select resources that preserve the preparedness in the area. However, the results also indicate that there is a risk that the tools increase the decision time. 

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