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  • 1.
    Abdul Malek, Nurul Aida
    et al.
    Universiti Tun Hussein Onn Malaysia (UTHM), Malaysia / Department of Production, University of Vaasa, Finland.
    Shahzad, Khuram
    Department of Production, University of Vaasa, Finland.
    Takala, Josu
    Department of Production, University of Vaasa, Finland.
    Bojnec, Stefan
    Faculty of Management, University of Primorska, Slovenia.
    Papler, Drago
    Faculty of Management, University of Primorska, Slovenia.
    Liu, Yang
    Department of Production, University of Vaasa, Finland.
    Analyzing Sustainable Competitive Advantage: Strategically Managing Resource Allocations to Achieve Operational Competitiveness2015In: Management and Production Engineering Review, ISSN 2080-8208, E-ISSN 2082-1344, Vol. 6, no 4, p. 70-86Article in journal (Refereed)
    Abstract [en]

    In today’s dynamic business environment, a key challenge for all companies is to make adaptive adjustments to their manufacturing strategy. This study demonstrates the competitive priorities of manufacturing strategy in hydro-power case company to evaluate the level of sustainable competitive advantage and also to further analyze how business strategies are aligned with manufacturing strategies. This research is based on new holistic analytical evaluation of manufacturing strategy index, sense and respond, and sustainable competitive advantage models. These models help to describe, evaluate, and optimize resource allocation to meet the performance requirements in dynamic decision making. Furthermore, these models evaluate operational competitiveness for manufacturing strategies according to the multi-criteria priority. The results show that the adjustments of competitive priorities in manufacturing strategies by implementing the proposed holistic analytical models are helpful in strategically managing business operations. The discussion derives the most critical attributes in business operations while alignment of resource allocation with competitive priorities help to strategically focus those attributes. In conclusion, we argue that resource allocation and manufacturing strategies have become the most important capabilities in a business environment where companies focus to get a sustainable competitive advantage.

    Download full text (pdf)
    fulltext
  • 2. Order onlineBuy this publication >>
    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.    

    List of papers
    1. 3D Halftoning based on Iterative Method Controlling Dot Placement
    Open this publication in new window or tab >>3D Halftoning based on Iterative Method Controlling Dot Placement
    2020 (English)Conference paper, Oral presentation with published abstract (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.

    Keywords
    3D printing, 3D halftoning, Surface reproduction
    National Category
    Media Engineering
    Identifiers
    urn:nbn:se:liu:diva-171744 (URN)10.2352/ISSN.2169-4451.2020.36.69 (DOI)
    Conference
    Printing for Fabrication, Online 2020, October 19-21
    Available from: 2020-12-01 Created: 2020-12-01 Last updated: 2023-09-26Bibliographically approved
    2. 3D Surface Structures and 3D Halftoning
    Open this publication in new window or tab >>3D Surface Structures and 3D Halftoning
    2020 (English)Conference paper, Published paper (Refereed)
    Abstract [en]

    As 3D printing is becoming increasingly popular, the demand for high quality surface reproduction is also increasing. Like in 2D printing, halftoning plays an important role in the quality of the surface reproduction. Developing advanced 3D halftoning methods for 3D printing and adapting them to the structure of the surface is therefore essential for improving surface reproduction quality. In this paper, an extension of an iterative 2D halftoning method to 3D is used to apply different halftone structures on 3D surfaces. The results show that using different halftones based on the 3D geometrical structure of the surface and/or the viewing angle in combination with the structure of the texture being mapped on the surface can potentially improve the quality of the appearance of 3D surfaces.

    Place, publisher, year, edition, pages
    The Society for Imaging Science and Technology, 2020
    Keywords
    3D halftoning, Hybrid halftoning, 3D surface structures
    National Category
    Media Engineering
    Identifiers
    urn:nbn:se:liu:diva-170797 (URN)10.2352/ISSN.2169-4451.2020.36.75 (DOI)
    Conference
    Printing for Fabrication 2020
    Available from: 2020-10-22 Created: 2020-10-22 Last updated: 2024-01-02Bibliographically approved
    3. The Effect of Halftoning on the Appearance of 3D Printed Surfaces
    Open this publication in new window or tab >>The Effect of Halftoning on the Appearance of 3D Printed Surfaces
    2021 (English)Conference paper, Published 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.

    Keywords
    3D printing, Halftoning, Surface appearance
    National Category
    Media Engineering
    Identifiers
    urn:nbn:se:liu:diva-180696 (URN)
    Conference
    47th Annual Conference of Iarigai
    Available from: 2021-10-29 Created: 2021-10-29 Last updated: 2023-09-26Bibliographically approved
    4. Structure-Aware Halftoning Using the Iterative Method Controlling the Dot Placement
    Open this publication in new window or tab >>Structure-Aware Halftoning Using the Iterative Method Controlling the Dot Placement
    2021 (English)In: Journal of Imaging Science and Technology, ISSN 1062-3701, E-ISSN 1943-3522, Vol. 65, no 6Article in journal (Refereed) Published
    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.

    Place, publisher, year, edition, pages
    I S & T-SOC IMAGING SCIENCE TECHNOLOGY, 2021
    Keywords
    Halftoning, Structure-Aware Halftoning, Hough Transform, Image Quality Evaluation
    National Category
    Media Engineering
    Identifiers
    urn:nbn:se:liu:diva-181613 (URN)10.2352/j.imagingsci.technol.2021.65.6.060404 (DOI)000734009600011 ()
    Note

    Funding: ApPEARS (Appearance Printing European Advanced Research School); European Unions Horizon 2020 programme under the Marie Skodowska-Curie [814158]

    Available from: 2021-12-04 Created: 2021-12-04 Last updated: 2023-09-26Bibliographically approved
    5. Structure-Aware Color Halftoning with Adaptive Sharpness Control
    Open this publication in new window or tab >>Structure-Aware Color Halftoning with Adaptive Sharpness Control
    2022 (English)In: Journal of Imaging Science and Technology, ISSN 1062-3701, E-ISSN 1943-3522, Vol. 66, no 6, article id 060404Article in journal (Refereed) Published
    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.

    Place, publisher, year, edition, pages
    I S & T-SOC IMAGING SCIENCE TECHNOLOGY, 2022
    National Category
    Media Engineering
    Identifiers
    urn:nbn:se:liu:diva-192705 (URN)10.2352/J.ImagingSci.Technol.2022.66.6.060404 (DOI)000939908300011 ()
    Note

    Funding Agencies|ApPEARS (Appearance Printing European Advanced Research School); European Unions Horizon 2020 programme under the Marie Sklodowska-Curie grant [814158]

    Available from: 2023-03-31 Created: 2023-03-31 Last updated: 2023-09-26
    6. Effect of halftones on printing iridescent colors
    Open this publication in new window or tab >>Effect of halftones on printing iridescent colors
    2023 (English)In: 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, Published 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.

    Place, publisher, year, edition, pages
    The Society for Imaging Science and Technology, 2023
    National Category
    Media Engineering
    Identifiers
    urn:nbn:se:liu:diva-197992 (URN)
    Conference
    IS&T Electronic Imaging
    Available from: 2023-09-20 Created: 2023-09-20 Last updated: 2023-09-26
    Download full text (pdf)
    fulltext
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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.

    Download (png)
    preview image
  • 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.

    Download (png)
    preview image
  • 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.

    Download (png)
    preview image
  • 8.
    Abo Al Ahad, George
    et al.
    Linköping University, Department of Management and Engineering, Production Economics.
    Salami, Abbas
    Linköping University, Department of Management and Engineering, Production Economics.
    Machine Learning for Market Prediction: Soft Margin Classifiers for Predicting the Sign of Return on Financial Assets2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Forecasting procedures have found applications in a wide variety of areas within finance and have further shown to be one of the most challenging areas of finance. Having an immense variety of economic data, stakeholders aim to understand the current and future state of the market. Since it is hard for a human to make sense out of large amounts of data, different modeling techniques have been applied to extract useful information from financial databases, where machine learning techniques are among the most recent modeling techniques. Binary classifiers such as Support Vector Machines (SVMs) have to some extent been used for this purpose where extensions of the algorithm have been developed with increased prediction performance as the main goal. The objective of this study has been to develop a process for improving the performance when predicting the sign of return of financial time series with soft margin classifiers.

    An analysis regarding the algorithms is presented in this study followed by a description of the methodology that has been utilized. The developed process containing some of the presented soft margin classifiers, and other aspects of kernel methods such as Multiple Kernel Learning have shown pleasant results over the long term, in which the capability of capturing different market conditions have been shown to improve with the incorporation of different models and kernels, instead of only a single one. However, the results are mostly congruent with earlier studies in this field. Furthermore, two research questions have been answered where the complexity regarding the kernel functions that are used by the SVM have been studied and the robustness of the process as a whole. Complexity refers to achieving more complex feature maps through combining kernels by either adding, multiplying or functionally transforming them. It is not concluded that an increased complexity leads to a consistent improvement, however, the combined kernel function is superior during some of the periods of the time series used in this thesis for the individual models. The robustness has been investigated for different signal-to-noise ratio where it has been observed that windows with previously poor performance are more exposed to noise impact.

    Download full text (pdf)
    ML for Market Predictions
  • 9.
    Abramsson, Jonatan
    Linköping University, The Department of Physics, Chemistry and Biology.
    First-principle of Sc / Cr multilayers for x-ray mirrors applications2008Independent thesis Basic level (professional degree), 20 points / 30 hpStudent thesis
    Abstract [en]

    In order to produce x-ray mirrors the Thin Film Physics group at IFM grows Cr/Sc multilayers, with a typical thickness of the individual layers in the range 5-20 Å, and with as many periods as possible (a few hundred).

    The quality of the multilayer interfaces is crucial for their performance as mirrors. For thick layers poly-crystalline multilayers form with an interface quality that is too poor for the use as x-ray mirrors. For thinner layers, however, amorphous layers are formed with a much better quality of the interface.

    The goal of this project was to understand the formation of amorphous multilayers. Unfortunately it is impossible with the present day's theoretical tools to determine the structure of amorph interfaces. It is also impossible to calculate the interface structure for elements with large mismatch in size.

    So we have to construct interface models that are both simple and based on physical arguments.

    Download full text (pdf)
    FULLTEXT01
  • 10.
    Aduwa, Franklin
    Linköping University, Department of Management and Engineering, Production Economics.
    Implementing DDMRP: Supply Chain transformation Through Inventory Management2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    An organization's systematic operation and supply chain management are the criteria for developing a sustainable competitive advantage over other companies. However, fulfilling this goal has become increasingly difficult in today's business environment, as traditional planning and control methods were not designed to withstand such difficulty, hence making the supply chain very complex. This complexity emanated due to high demand and supply variability in the system. In this regard, companies experience a lack of required materials or unavailability of the materials needed for production purposes. Such a situation prompts the movement of planners migrating from the traditional deterministic domain, Push-based MRP methodology to a more systematic pull-based demand-driven material requirement planning (DDMRP) approach that works in a more complex and unstable business environment, with an unparalleled characteristic for maintaining flow stability in the manufacturing operation.

    The establishment of DDMRP is for the sole purpose of maintaining a proper flow with the main intent of inventory monitoring as well as the associated cost. This proposition suggests the identification of specific items at strategic positions for planning maintenance flow in the production process. It basically centers on regular monitoring of the inventory buffer level sufficient enough to sustain the flow in order to avoid any operational disruption.

    The Insufficient understanding of the DDMRP methodology makes the practitioners unable to implement the concept in a proper manner, thereby not achieving the proposed result. This research, however, investigates the subject of DDMRP as a more efficient planning and execution strategy for proper flow management affecting the overall dynamics of supply chain management.

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    fulltext
  • 11.
    Agerstig Rosenqvist, Morgan
    Linköping University, Department of Science and Technology, Physics, Electronics and Mathematics. Linköping University, Faculty of Science & Engineering.
    Evaluation of algorithms for accurate micro-doppler effects measurement in FMCW radar2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Micro-Doppler effects are phenomena that occur because of micro-motion. A micro-motion is either a vibration, rotation, or acceleration which is small relative to the motion of the target. These effects can be used in order to characterize a target through their signature movement. These effects were captured using a Frequency Modulated Continous Wave (FMCW) radar on several targets with a distinct signature. The targets were a four-armed drone, a cyclist, and a pedestrian. Using conventional- and super-resolution algorithms allows the user to process the captured data. To best be able to determine these signatures, different algorithms were used, Short-Time Fourier Transform (STFT), Smoothed Pseudo-Wigner-Ville Distribution (SPWVD), Pade Fourier approximation (PFA), and MUltiple SIgnal Classification (MUSIC). The comparison of the algorithms on the measured data was done in MATLAB where the best possible scenario was taken. From the comparison, it was noticed that in order to capture the most details, the MUSIC, PFA, STFT, and SPWVD performed the best with a decreasing order.

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  • 12.
    Ahlin, Katarina
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Bredin, Sanna
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    European Aviation Crisis Management2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Our aim is to investigate and evaluate the efficiency of crisis management in European aviation, and to recommend enhancements. To fulfill this, we mapped the current crisis management plans and created a fictive scenario where a cyber-attack shut down the power at five of the major airports in Europe. Air traffic in Europe was reconstructed to a chosen day; the 16th of September 2013, and the reconstructed traffic situation was used in the scenario. We also created a model, for the purpose of showing the effect of a cut in time for the steps in the crisis management plan may have on the traffic waiting to depart at the closed airports. When using these means, we could implement the crisis management plans on the fictive scenario and make changes to the plans for a new implementation. The existing crisis management plans were compared to the modified plans made by us, and it was found that usage of a common platform for the different stakeholders involved in the crisis could improve the efficiency of the crisis management.

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  • 13.
    Ahlsén, Olle
    Linköping University, Department of Management and Engineering, Carl Malmsten - furniture studies.
    Att löta en ring, eller ser jag mönster i cirklar?: En undersökning av en underutnyttjad snickeriteknik2016Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [sv]

    Var, när, hur och vad jag kom fram till.

    Utifrån egna erfarenheter från olika uppgifter under min treåriga utbildning och utifrån de ytterligare trevare jag gjort inom ramen för mitt examensarbete, så har jag undersökt lötade ringars tekniska, estetiska och berättande möjligheter.

    Med olika hållbarhetstester är styrkan prövad och med ett antal varierade dekorativa bearbetningar inom lötningstekniken är de estetiska möjligheterna synliggjord.

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    Att löta en ring, eller ser jag mönster i cirklar
  • 14. 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)
  • 15.
    Ahrenberg, Lars
    Linköping University, Department of Computer and Information Science, Human-Centered systems. Linköping University, Faculty of Science & Engineering.
    Alignment2014In: Routledge Encyclopedia of Translation Technology / [ed] Chan Sin-wai, London and New York: Routledge, 2014, p. 395-408Chapter in book (Refereed)
  • 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.
    Al Farra, Hussni
    Linköping University, Department of Management and Engineering, Logistics & Quality Management.
    Acceptance Tests – FAT & SAT: An Empirical Case Study of Utility Poles2016Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    The overall purpose of this project is to devise improved quality acceptance procedures to examine quality characteristics of utility poles at the factory of the supplier (FAT) and on-site upon receipt by the customer (SAT). To that end, the thesis draws upon available standards, literature, and industry practices regarding wood, fiberglass and steel poles. As far as the design of the research, a single case study of a major power company was chosen. Then, a data collection plan was developed in order to build upon the existing knowledge found in the literature, and upon the data that can be collected from three of the Company’s suppliers, in addition to the Technical Research Institute of Sweden (SP). Documents’ analysis, interviews, observations, and a survey were the tools of that plan. It was found that criteria, inspection and test methods of wood poles are all sufficiently covered in the standards and the literature; for wood is the most commonly used material for utility poles. Next, in coverage of research, are the steel poles; while there is currently no standard that covers fiberglass utility poles. Indeed, quality characteristics, criteria, and acceptance procedures can altogether form parts of a sustainable solution, as long as the quality is managed as a process whether at the Company’s end or at the fabrication sites; that is especially true if there is some form of backward partnership between the Company and its suppliers.

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  • 19.
    Alenvret, Caroline
    et al.
    Linköping University, Department of Management and Engineering, Project Innovations and Entrepreneurship. Linköping University, Faculty of Science & Engineering.
    Evaldsson, Johannes
    Linköping University, Department of Management and Engineering, Project Innovations and Entrepreneurship. Linköping University, Faculty of Science & Engineering.
    Creating customer value through knowledge integration: How internal stakeholders can be involved in the product development process2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The increasing globalisation of the market is followed by increased competition between organisations. Therefore it becomes more important to create products with high customer value. To be able to create customer value, deep understanding of the customers’ needs must be obtained by employees, shared between them and transformed into products. Further consequences of globalisation are increasing differences between customers’ needs, which results in demand for customisable and flexible products.The purpose of this study was to analyse how organisations can create more customer value through increased knowledge integration. The focus was on how knowledge that already resides within a globally dispersed organisation can be integrated during the product development process.This study showed that customer value is created throughout the product development process by integrating the knowledge held by R&D and internal stakeholders. Different types of value are created at different phases in the product development process. One important finding is that different parts of the augmented value are created throughout the entire product development process. Since employees obtain different knowledge depending on which customer they interact with, it is important to utilise knowledge from a large number of employees with different roles and in different countries. Hence, the significance of knowledge integration must be disseminated and understood across the organisation. After completing the product development process additional customer value is created by the internal stakeholders’ who sell and implement the product, but it is during the product development process that the basis for their value creation is established.Knowledge needs to be integrated in a formalised, repeatable way, so that the R&D department can ensure that the right product is developed at the right time. Integration means that the tacit knowledge that resides within one employee is codified into an explicit form that can be exploited by more employees. Therefore, four steps must be performed and repeated iteratively to create and spread knowledge throughout the organisation. The first step includes communication by exchanging tacit knowledge. The second step entails documenting the knowledge, and the third step involves combining the knowledge residing in the organisations into one common knowledge system. The final step includes distributing the knowledge so that it recievess wide attention within the organisation. Several factors that have a negative impact on these four steps, and knowledge integration, need to be countered somehow. However, it was found that there are several mechanisms that facilitate knowledge integration, and most often the presence of several mechanisms at the same time had a better effect.

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    Creating customer value through knowledge integration
  • 20.
    Alexandersson, Martin
    Linköping University, Department of Management and Engineering, Carl Malmsten - furniture studies. Möbelsnickeri.
    Parkettläggning: med massivträ som utgångspunkt2015Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    This thesis is about furniture parquetry and various techniques. Parquetry can be describe as wooden, 2-dimensional patterns used to garnish furniture and other products. It is manufactured in thin veneer layer and applied to the surface. By using thin veneer we are able to minimize stresses in the material, which results in tight joints. In Europe, furniture parquetry is traditionally created by wood veneer pieces that has been formed and joined into a pattern. There are also other proven techniques developed during different stages in history and in different places in the world.

    In my thesis I describe some of those established techniques and some of my experiments in the subject. The report is based on literature studies, observations of movie clips, interviews and empirical practical studies. I have compared different techniques to see in what ways it is possible to rationalize the production of furniture parquetry. At the same time I wanted to try and develop a method that makes it possible to create parquetry patterns containing round shapes. In this way I hope to contribute to the development and modernization in the area. 

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    Parkettläggning - Martin Alexandersson
  • 21.
    Alghazi, Ziad
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Wireless instrumentation2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Syftet med detta examensarbete var att undersöka om det finns möjlighet att implementera en trådlöst instrumenterings kit från Emerson Rosemount Process AB på dagens styrsystem som finns på Siemens gasturbiner. En prototyp skapades som bygger på Siemens Simatic PCS-7 med en styrenhet och en switch. Där efter implementerades Emerson Wireless gateway och två trådlösa instrument. I examanearbetet skapades även en logik som hanterar kommunikationen mellan simatic och gateway. Modbus RTU och TCP/IP är kommunikationsprotokollet som användes under arbetet. En undersökning om den uppsättningen klarar av de atex (ATmosphères EXplosibles )och sil (saftey integrity level ) krav gjordes, för att säkerställa om det finns möjligheter att implementera detta på dagens tillverkningsprocess. Utöver dessa kontrollerades om det råder för och nackdelar med den trådlösa allternativet inom IT-säkerhet, instrumentdiagnostik och störkänslighet. Arbetet fullgjordes på Siemens Industrial Turbomachinery i Finspång tillsammans med företagets utvecklingsavdelning för styrsystem.

  • 22.
    Algvere, Ebba
    Linköping University, Department of Computer and Information Science.
    Att designa effektivt lärande med blandade lärmiljöer: Hur lärmiljöer och dess aktiviteter inom blandade lärmiljöer påverkar kunskapsutveckling och förtroende för organisationen2019Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [sv]

    Denna studie har undersökt hur olika lärmiljöer inom ett utbildningsupplägg med blandade lärmiljöer skiljer sig i upplevelse, kunskapsutveckling samt förtroende. Vidare har studien undersökt om det finns någon skillnad mellan grupper, med prefererad ordning på lärmiljöer inom ett utbildningsupplägg med blandade lärmiljöer, och prefererad inläringsstil. Fyra olika inläringsstilar, av Honey och Mumford (2000), har använts i studien. Frågeställningarna har undersökts och besvarats genom en triangulering, en kombination av kvalitativa och kvantitativa metoder. Kvalitativ data har samlats in genom semistrukturerade intervjuer och har sedan följt en tematisk analysprocess. Kvantitativ data har erhållits genom ett frågeformulär som sedan har analyserats med statistiska tester. Resultaten från den kvalitativa intervjudelen har visat på att olika lärmiljöer, e-lärande och föreläsning, skiljer sig samt kompletterar varandra med avseende på upplevelse, kunskapsutveckling och förtroende för arbetsgivare. Kvantitativa resultat från frågeformulär har visat på att det inte finns någon signifikant skillnad mellan grupper, som föredrar att börja ett utbildningsupplägg med blandade lärmiljöer med olik första lärmiljö, och styrka i prefererad inläringsstil. Detta innebär att det inte finns någon direkt koppling mellan föredragen ordning på lärmiljöer inom blandade lärmiljöer och prefererad inläringsstil. Denna studie har studerat ett kunskapsgap för hur blandade lärmiljöer bör struktureras. Studiens fynd kan därmed bidra till en bättre förståelse för hur framtida utbildningsupplägg med blandade lärmiljöer bör designas för effektivt lärande och maximal kunskapsutveckling.

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  • 23.
    Ali, A.
    et al.
    Malmo Univ, Sweden; Malmo Univ, Sweden; Speximo AB, Sweden.
    Skedung, L.
    RISE Res Inst Sweden Bioecon & Hlth, Sweden.
    Burleigh, S.
    Lund Univ, Sweden.
    Lavant, E.
    Malmo Univ, Sweden; Malmo Univ, Sweden.
    Ringstad, L.
    RISE Res Inst Sweden Bioecon & Hlth, Sweden.
    Anderson, Chris D
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Medicine Center, Department of Dermatology and Venerology.
    Wahlgren, M.
    Lund Univ, Sweden.
    Engblom, J.
    Malmo Univ, Sweden; Malmo Univ, Sweden.
    Relationship between sensorial and physical characteristics of topical creams: A comparative study on effects of excipients2022In: International Journal of Pharmaceutics, ISSN 0378-5173, E-ISSN 1873-3476, Vol. 613, article id 121370Article in journal (Refereed)
    Abstract [en]

    Rising consumer demands for safer, more natural, and sustainable topical products have led to increased interest in finding alternative excipients, while retaining functionality and cosmetic appeal. Particle-stabilized Pickering creams have emerged as possible alternatives to replace traditional surfactant-stabilized creams and are thus one of the focuses in this study. The aim of this paper was to study relationships between sensorial characteristics and physical properties to understand how different excipients affect these aspects, comparing one starch particle-stabilized and three surfactant-stabilized formulations. A human panel was used to evaluate sensorial perception, while physical properties were deduced by rheology and tactile friction, together with in vivo and ex vivo skin hydration measurements. The results show that sensorial attributes related to the application phase can be predicted with rheology, while afterfeel attributes can be predicted with tactile friction studies. Differences in rheological and sensory properties among surfactant-based creams could mainly be attributed to the type of emollients used, presence of thickeners and surfactant composition. Differences between surfactant-based creams and a Pickering cream were more evident in relation to the afterfeel perception. Presence of starch particles in the residual film on skin results in high tactile friction and low perception of residual coating, stickiness, greasiness, and slipperiness in sensorial afterfeel.

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  • 24.
    Ali, Islam
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Iqbal, Wasim
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Performance analysis of various antennas at 2.45 GHz2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this era of technology, there is a swift increase in the number of applications which operate at the Industrial Scientific Medical Band. The applications of this band ranges from home microwave oven to wireless local area networks (WLAN). Therefore, the design of antennas on this band is essential.

    This thesis work revolves around the detailed study and design of various antennas at 2.45 GHz. All the simulation of the antennas was performed using advanced design system (ADS). Microstrip antenna technology is commonly used in antenna design due to its advantages such as low-profile, small size and easy fabrication on printed circuit boards.

    Firstly, various antennas such as rectangular patch, square patch, dipole, inverted F and printed Yagi were designed using ADS and their different performance parameters such as input impedance matching, voltage standing wave ratio (VSWR), input reflection, and gain and directivity were discussed. Dipole antenna, inverted F and printed Yagi were fabricated on printed circuit board (PCB) to compare their measured and simulated results.

    At the end, a conclusion is drawn for different antennas based on their various performance parameters.

  • 25.
    Ali, M.
    et al.
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Svensk, Olle
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Zhen, Z.
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Suihkonen, S.
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Törmä, P.T.
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Lipsanen, H.
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Sopanen, M.
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Hjort, Klas
    Department of Engineering Sciences, Uppsala University, P.O. Box 534, SE-75121 Uppsala, Sweden.
    Jensen, Jens
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Reduced photoluminescence from InGaN/GaN multiple quantum well structures following 40 MeV iodine ion irradiation2009In: Physica. B, Condensed matter, ISSN 0921-4526, E-ISSN 1873-2135, ISSN 0921-4526, Vol. 404, no 23-24, p. 4925-4928Article in journal (Refereed)
    Abstract [en]

    The effects following ion irradiation of GaN-based devices are still limited. Here we present data on the photoluminescence (PL) emitted from InGaN/GaN multiple quantum well (MQW) structures, which have been exposed to 40 MeV I ion irradiation. The PL is reduced as a function of applied ion fluence, with essentially no PL signal left above 1011 ions/cm2. It is observed that even the ion fluences in the 109 ions/cm2 range have a pronounced effect on the photoluminescence properties of the MQW structures. This may have consequences concerning application of InGaN/GaN MQW’s in radiation-rich environments, in addition to defect build-up during ion beam analysis.

  • 26.
    Ali Mousa, Jaffer
    et al.
    Linköping University, Department of Computer and Information Science.
    Salim, Saleh
    Linköping University, Department of Computer and Information Science.
    Developing a web application for collecting conversations in lab rooms2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
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  • 27.
    Aliahmad, Abdulhamid
    et al.
    Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Kanda, Wisdom
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    McConville, Jennifer
    Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Urine recycling - Diffusion barriers and upscaling potential; case studies from Sweden and Switzerland2023In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 414, article id 137583Article in journal (Refereed)
    Abstract [en]

    In this study, we explored why urine recycling systems have failed to gain wide-scale expansion despite their high potential for food and fertilizer security. Additionally, we examined the future perception of urine recycling in Sweden and Switzerland, as these two countries are at the forefront of technological advancement. Along with identifying barriers, we also proposed pathways for overcoming those barriers and achieving the upscale. The analysis was conducted using the technological innovation (TIS) approach, which is technology-focused, i.e., revolves around emerging technologies. Additionally, the study provides a methodological contribution to the innovation systems research by employing the Delphi method in conjunction with urine recycling experts to enforce transparency and prevent bias in the analysis. For urine recycling to overcome its current challenges, actors must work collectively. There needs to be a combination of top-down and bottom-up efforts to achieve the upscaling pathways. Lobbying and knowledge provision are necessary to adjust the current regulatory framework in a manner that provides public and private incentives. For urine recycling to diffuse and break into the mainstream market, we must move beyond enthusiasts, innovators, and niche markets into the mass market (ordinary people); dedicated service providers can facilitate this process. Pilot projects have been found integral to urine recycling upscaling. Future work could conduct life cycle assessments on existing pilot projects to understand the environmental and economic performance of urine recycling systems when scaled up.

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  • 28.
    Allard, Olof
    Linköping University, Department of Computer and Information Science. Linköping University, Faculty of Arts and Sciences.
    Katastrofisk design: Ett designförslag för en digital scenarioeditor2014Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [sv]

    Målet med det här arbetet var att skapa en konceptuell designprototyp för en scenarioeditor åt en digital version av utbildningsverktyget Emergo Train System. Rapporten ämnar ta upp och presentera den arbetsprocess som lett fram till designprototypen och dess utvärdering. I rapporten tillkommer även en diskussion kring hur en scenarioeditor bör utformas för att stödja skapandet av ETS-scenarion samt hur ett flexibelt arbetssätt stöds i form av skapandet av scenariorepresentationer.

    Intervjuer genomfördes med instruktörer och systemansvarige för ETS, samt observationer av iordningställande av ett ETS-scenario. Datainsamlingen analyserades och resulterade i en kravspecifikation för den digitala scenarioeditorn. Den prototyp som utformades gjordes så i pappersformat och utvärderades tillsammans med personal från Katastrofmedicinskt centrum i Linköping. 

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  • 29.
    Alsteryd, Johan
    et al.
    Linköping University, Department of Management and Engineering, Industrial Economics.
    Johansson, Jakob
    Linköping University, Department of Management and Engineering, Industrial Economics.
    Strategier för effektivisering av informationsflöden för företag med komplexa produkter: En fallstudie av informationsflödet på Siemens Energy2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    De senaste decenniernas globaliseringstrend och samhällsutveckling har fått företag att inse att hanteringen av sin supply chain är nödvändig för att bibehålla konkurrenskraft. Internet och ökad digitalisering har förändrat konkurrenssituation på marknaden och information om produkter samt tjänster är mer lättillgängligt än någonsin. Företag som tillverkar komplexa produkter behöver hantera oerhört stora mängder information och på grund av detta blir det väsentligt att företagen utvecklar strategier för att effektivt hantera informationsflöden. Tidigare litteratur har identifierats som begränsad kring hur företag med komplexa produkter och system går till väga för att effektivisera informationsflöden och denna studie syftar där med till att undersöka hur sådana företag använder strategi och styr verktyg för att effektivisera informationsflödet och genom detta minska hanteringskostnader och förbättra kvalité.

    Denna studie genomförs på ett kvalitativt och abduktivt sätt med fokus på två teoretiska områden, Strategi för effektivisering av informationsflödet och Aktiviteter inom Supplier Quality Management. Dessa två teoretiska områden kombineras för att skapa en analysmodell där barriärer och möjligheter för att effektivisera informationsflödet för företag som tillverkar komplexa produkter identifieras. Analysmodellen används sedan för att analysera insamlade empiriska data från intervjuer av personer på det studerade fallföretaget. Resultaten från analysen sammanställdes i ett ramverk där styrverktyg, barriärer och möjligheter sammanställs för varje identifierat strategiskt element, vilket besvarar hur strategiska element kan användas för att effektivisera informationsflödet hos företag med komplexa produkter.Vidare i ramverket presenteras hur aktiviteter inom Supplier Quality Management kan integreras i strategin för att effektivisera informationsflödet, samt identifierade barriärer som förhindrar integration av aktiviteterna med tillhörande möjligheter att lösa barriärerna.

    Som slutsats kan det konstateras att rapporten presenterar ett ramverk som besvara hur strategi kan utformas för att effektivisera informationsflödet. Ramverket kan även användas för att analysera strategier för att effektivisera informationsflödet hos företag med komplexa produkter.

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  • 30.
    Altgärde, Noomi
    Linköping University, Department of Physics, Chemistry and Biology.
    Local release of lithium from sol-gel coated orthopaedic screws: an in vitro and in vivo study2009Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

     

    In orthopaedic practice, fractures are usually stabilised with metal screws or rods. This is done in order to keep the fracture parts in place during the rather slow healing process. The healing time can potentially be reduced by local- or systemic treatment with different bone promoting drugs. In later years, lithium, otherwise used to treat bipolar disease, has shown promise to be such a drug.

     

    The aim of this master thesis was to find a way to coat metal bone screws with lithium and to characterise the coating. The coating was to be designed in such a way that it could release lithium to the surrounding bone tissue.

     

    Lithium chloride was incorporated into a titanate sol-gel and attached to silicon wafers and stainless steel screws by dip coating. Wafers were used for initial in vitro studies of how lithium changed coating characteristics. This was studied using ellipsometry, AFM and SEM. Lithium is most probably physisorbed and not incorporated into the network building up the sol-gel. Coating structure is changed as more lithium is incorporated. For large amounts of lithium, the nanoparticles normally formed when curing the sol-gel are inhibited. One effect of this is reduced bioactivity, seen as a reduced ability for calcium phosphate crystals to nucleate on the coating when immersed in simulated body fluid.

    Lithium release was investigated using AAS. Lithium is released from the coating, showing a burst effect. By changing the number of coating layers used, the release profile can be partly altered. The coating was also applied to screws, showing good attachment, and the lithium release profile was similar to the one seen from wafers.

    Finally, a screw model was used in rats to assess the effect of local lithium treatment from screws and systemic lithium treatment on fracture healing. In the model, a screw was inserted in tibia, mimicking a fracture. When the bone around the screw was healed, a pullout test was performed, giving information about the strength of the bone surrounding the screw. No significant difference could be found for either local- or systemic lithium treatment compared to control. However, when evaluating the strength of intact bone in a similar way, a positive effect of systemic lithium treatment could be seen. Therefore, it is still likely that lithium has a positive effect on bone and further studies are needed to fully evaluate its role in fracture healing.

     

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  • 31.
    Amundin, Mats
    et al.
    Kolmården Wildlife Park.
    Hållsten, Henrik
    Filosofiska institutionen, Stockholms universitet.
    Eklund, Robert
    Linköping University, Department of Culture and Communication, Language and Culture. Linköping University, Faculty of Arts and Sciences.
    Karlgren, Jussi
    Kungliga Tekniska Högskolan.
    Molinder, Lars
    Carnegie Investment Bank, Swedden.
    A proposal to use distributional models to analyse dolphin vocalisation2017In: Proceedings of the 1st International Workshop on Vocal Interactivity in-and-between Humans, Animals and Robots, VIHAR 2017 / [ed] Angela Dassow, Ricard Marxer & Roger K. Moore, 2017, p. 31-32Conference paper (Refereed)
    Abstract [en]

    This paper gives a brief introduction to the starting points of an experimental project to study dolphin communicative behaviour using distributional semantics, with methods implemented for the large scale study of human language.

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    A proposal to use distributional models to analyse dolphin vocalisation
  • 32.
    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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  • 33.
    Andersson, Ann-Christine
    et al.
    Linköping University, Department of Management and Engineering, Quality Technology and Management. Linköping University, The Institute of Technology.
    Elg, Mattias
    Linköping University, HELIX Vinn Excellence Centre. Linköping University, Department of Management and Engineering, Quality Technology and Management. Linköping University, The Institute of Technology.
    Perseius, Kent-Inge
    Kalmar County Council, Sweden.
    Idwall, Ewa
    Malmö University, Sweden .
    Evaluating a questionnaire to measure improvement initiatives in Swedish healthcare2013In: BMC Health Services Research, E-ISSN 1472-6963, Vol. 13, no 48Article in journal (Refereed)
    Abstract [en]

    BACKGROUND:

    Quality improvement initiatives have expanded recently within the healthcare sector. Studies have shown that less than 40% of these initiatives are successful, indicating the need for an instrument that can measure the progress and results of quality improvement initiatives and answer questions about how quality initiatives are conducted. The aim of the present study was to develop and test an instrument to measure improvement process and outcome in Swedish healthcare.

    METHODS:

    A questionnaire, founded on the Minnesota Innovation Survey (MIS), was developed in several steps. Items were merged and answer alternatives were revised. Employees participating in a county council improvement program received the web-based questionnaire. Data was analysed by descriptive statistics and correlation analysis. The questionnaire psychometric properties were investigated and an exploratory factor analysis was conducted.

    RESULTS:

    The Swedish Improvement Measurement Questionnaire consists of 27 items. The Improvement Effectiveness Outcome dimension consists of three items and has a Cronbach's alpha coefficient of 0.67. The Internal Improvement Processes dimension consists of eight sub-dimensions with a total of 24 items. Cronbach's alpha coefficient for the complete dimension was 0.72. Three significant item correlations were found. A large involvement in the improvement initiative was shown and the majority of the respondents were satisfied with their work.

    CONCLUSIONS:

    The psychometric property tests suggest initial support for the questionnaire to study and evaluate quality improvement initiatives in Swedish healthcare settings. The overall satisfaction with the quality improvement initiative correlates positively to the awareness of individual responsibilities.

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    Andersson et al Evaluation a questionnaire 2013
  • 34.
    Andersson, Daniel
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Sandholm, Christian
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Total Cost Analysis of frame suppliers in construction2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Gotec, som är ett bygg och förvaltningsföretag, är just nu inne på etapp ett av ett byggprojekt i Vallastaden, Linköping. För etapp ett slöt Gotec ett avtal med den polska stomleverantören Baumat, att de skulle leverera samtliga stommar till Gotecs byggnader i projektet. Valet av leverantör baserades till största del på det låga inköpspriset. Dock upplever Gotec idag att det har uppstått vissa problem med Baumat som leverantör. Ett problem som Gotec upplever är att kommunikationen inte har fungerat så bra som de hade hoppats på, detta då engelskan är ytterst bristfällig inom Baumat. Andra problem som märkts av under samarbetet är bland annat att flexibiliteten och leveransprecisionen inte har varit perfekt. Detta har lett till att leveransförseningar har uppstått som i sin tur har givit upphov till extra kostnader, så kallade ÄTOR. Denna fallstudie utreder vilken leverantör av stommar som skulle vara det bästa alternativet för Gotec att använda sig av vid ett byggprojekt i Vallastaden i framtiden. En leverantör från ett lågkostnadsland eller en leverantör från Sverige. De leverantörer som utreds är Gotecs nuvarande leverantör Baumat som representerar en leverantör från ett lågkostnadsland och Strängbetong som representerar en leverantör från Sverige.

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    Total Cost Analysis of frame suppliers in construction
  • 35.
    Andersson, Elise
    Linköping University, Department of Management and Engineering, Carl Malmsten - furniture studies. Linköping University, The Institute of Technology.
    In Varying Shades of Brown: Searching the colourful past of a 18th century masterpiece2012Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The colourful past of the late 18th century marquetry furniture has seldom been highlighted. Through ageing and environmental influences, colourful marquetry furniture has lost their original expression. The current knowledge of how Swedish cabinet-makers in the late 18th century used dyes to colour their furniture is limited. Trace of colour has been observed and the use of dyes has been mentioned, but deeper research in this filed is missing.

    A visual examination and studies of archive documents and previous research have been performed to investigate the colourful past of Gottlieb Iwerssons masterpiece, a secretaire in Gustavian style made for the king Gustav III. The result shows that the secretaire has a colourful past in accordance with its original drawing. A hypothetical picture has been created to illustrate the colourful original appearance.

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  • 36.
    Andersson, Filip
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    GPGPU-Sim2014Independent thesis Basic level (university diploma), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    This thesis studies the impact of hardware features of graphics cards on performance of GPU computing using GPGPU-Sim simulation software tool. GPU computing is a growing topic in the world of computing, and could be an important milestone for computers. Therefore, such a study that seeks to identify the performance bottlenecks of the program with respect to hardware parameters of the devvice can be considered an important step towards tuning devices for higher efficiency.

    In this work we selected convolution algorithm - a typical GPGPU application - and conducted several tests to study different performance parameters. These tests were performed on two simulated graphics cards (NVIDIA GTX480, NVIDIA Tesla C2050), which are supported by GPGPU-Sim. By changing the hardware parameters of graphics card such as memory cache sizes, frequency and the number of cores, we can make a fine-grained analysis on the effect of these parameters on the performance of the program.

    A graphics card working on a picture convolution task releis on the L1 cache but has the worst performance with a small shared memory. Using this simulator to run performance tests on a theoretical GPU architecture could lead to better GPU design for embedded systems.

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  • 37.
    Andersson, Johan
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Schelander, Adam
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Design and verification of automotive power supply2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the current and next generation automotive telematic platforms, high demands are put on high efficiency power supplies. This thesis investigates different switch mode power converter solutions that operates with high efficiency for both low and high power loads. A market survey was conducted alongside meetings with ACTIA Nordic and their subcontractors. Three solutions from the market survey were selected for further investigation. One solution from the investigation was selected and implemented as a demonstration platform for further testing. The result shows a full test sequence for the designed power supply solution.

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    Design and verification of automotive power supply
  • 38.
    Andersson, Jon Martin
    Linköping University, Department of Physics, Chemistry and Biology, Plasma and Coating Physics. Linköping University, The Institute of Technology.
    Controlling the Formation and Stability of Alumina Phases2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this work, physical phenomena related to the growth and phase formation of alumina, Al2O3, are investigated by experiments and computer calculations. Alumina finds applications in a wide variety of areas, due to many beneficial properties and several existing crystalline phases. For example, the α and κ phases are widely used as wear-resistant coatings due to their hardness and thermal stability, while, e.g., the metastable γ and θ phases find applications as catalysts or catalyst supports, since their surface energies are low and, hence, they have large surface areas available for catalytic reactions.

    The metastable phases are involved in transition sequences, which all irreversibly end in the transformation to the stable α phase at about 1050 °C. As a consequence, the metastable aluminas, which can be grown at low temperatures, cannot be used in high temperature applications, since they are destroyed by the transformation into α. In contrast, α-alumina, which is the only thermodynamically stable phase, typically require high growth temperatures (~1000 °C), prohibiting the use of temperature sensitive substrates. Thus, there is a need for increasing the thermal stability of metastable alumina and decreasing the growth temperature of the α phase.

    In the experimental part of this work, hard and single-phased α-alumina thin films were grown by magnetron sputtering at temperatures down to 280 °C. This dramaticdecrease in growth temperature was achieved by two main factors. Firstly, the nucleation stage of growth was controlled by pre-depositing a chromia “template” layer, which is demonstrated to promote nucleation of α-alumina. Secondly, it is shown that energetic bombardment was needed to sustain growth of the α phase. Energy-resolved mass spectrometry measurements demonstrate that the likely source of energetic bombardment, in the present case, was oxygen ions/atoms originating from the target surface. Overall, these results demonstrate that low-temperature α-alumina growth is possible by controlling both the nucleation step of growth as well as the energetic bombardment of the growing film. In addition, the mass spectrometry studies showed that a large fraction of the deposition flux consisted of AlO molecules, which were sputtered from the target. Since the film is formed by chemical bonding between the depositing species, this observation is important for the fundamental understanding of alumina thin film growth.

    In the computational part of the work, the effect of additives on the phase stability of α- and θ-alumina was investigated by density functional theory calculations. A systematic study was performed of a large number of substitutional dopants in the alumina lattices. Most tested dopants tended to reverse the stability between α- and θ-alumina; so that, e.g., Modoping made the θ phase energetically favored. Thus, it is possible to stabilize the metastable phases by additives. An important reason for this is the physical size of the dopant ions with respect to the space available within the alumina lattices. For example, large ions induced θ stabilization, while ions only slightly larger than Al, e.g., Co and Cu, gave a slight increase in the relative stability of the α phase. We also studied the stability of some of these compounds with respect to pure alumina and other phases, containing the dopants, with the result that phase separations are energetically favored and will most likely occur at elevated temperatures.

    List of papers
    1. Microstructure of α-alumina thin films deposited at low temperatures on chromia template layers
    Open this publication in new window or tab >>Microstructure of α-alumina thin films deposited at low temperatures on chromia template layers
    2004 (English)In: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 22, no 1, p. 117-121Article in journal (Refereed) Published
    Abstract [en]

    Radio frequency sputtering has been used to deposit -alumina (-Al2O3) thin films at substrate temperatures of 280–560 °C. The films are shown to be single phased and hard. Nanoindentation gives values of 306±31 and 27±3 GPa for elastic modulus and hardness, respectively, for a substrate temperature of 280 °C. Growth of the phase was achieved by in situ predeposition of a chromia template layer. Chromia crystallizes in the same hexagonal structure as -alumina, with a lattice mismatch of 4.1% in the a- and 4.6% in the c-parameter, and is shown to nucleate readily on the amorphous substrates (silicon with a natural oxide layer). This results in local epitaxy of -alumina on the chromia layer, as is shown by transmission electron microscopy. The alumina grains are columnar with grain widths increasing from 22±7 to 41±9 nm, as the temperature increases from 280 to 560 °C. This is consistent with a surface diffusion dominated growth mode and suggests that -alumina deposition at low temperatures is possible once initial grain nucleation has occurred. Results are also presented demonstrating chromia/-alumina growth on a technological substrate (Haynes230 Ni-based super alloy, Haynes International, Inc.).

    Keywords
    alumina, chromium compounds, sputtered coatings, indentation, elastic moduli, hardness, sputter deposition, transmission electron microscopy, epitaxial layers, grain size, surface diffusion, nucleation, wear resistant coatings, thermal barrier coatings
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-13578 (URN)10.1116/1.1636157 (DOI)
    Available from: 2008-11-13 Created: 2008-09-29 Last updated: 2017-12-13
    2. Phase control of Al2O3 thin films grown at low temperatures
    Open this publication in new window or tab >>Phase control of Al2O3 thin films grown at low temperatures
    Show others...
    2006 (English)In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 513, no 1-2, p. 57-59Article in journal (Refereed) Published
    Abstract [en]

    Low-temperature growth (500 °C) of α-Al2O3 thin films by reactive magnetron sputtering was achieved for the first time. The films were grown onto Cr2O3 nucleation layers and the effects of the total and O2 partial pressures were investigated. At 0.33 Pa total pressure and ≥ 16 mPa O2 partial pressure α-Al2O3 films formed, while at lower O2 pressure or higher total pressure (0.67 Pa), only γ phase was detected in the films (which were all stoichiometric). Based on these results we suggest that α phase formation was promoted by a high energetic bombardment of the growth surface. This implies that the phase content of Al2O3 films can be controlled by controlling the energy of the depositing species. The effect of residual H2O (10− 4 Pa) on the films was also studied, showing no change in phase content and no incorporated H (< 0.1%). Overall, these results are of fundamental importance in the further development of low-temperature Al2O3 growth processes.

    Place, publisher, year, edition, pages
    Elsevier, 2006
    Keywords
    Aluminum oxide, Chromium oxide, Sputtering, Ion bombardment, X-ray diffraction
    National Category
    Physical Sciences
    Identifiers
    urn:nbn:se:liu:diva-14318 (URN)10.1016/j.tsf.2006.01.016 (DOI)
    Note
    Original publication: Andersson, J.M., Wallin, E., Helmersson, U., Kreissig, U. and Münger, E.P., Phase control of Al2O3 thin films grown at low temperatures, 2006, Thin Solid Films, (513), 1-2, 57-59. http://dx.doi.org/10.1016/j.tsf.2006.01.016. Copyright: Elsevier B.V., http://www.elsevier.com/ Available from: 2007-03-02 Created: 2007-03-02 Last updated: 2017-12-13Bibliographically approved
    3. Molecular content of the deposition flux during reactive Ar/O2 magnetron sputtering of Al
    Open this publication in new window or tab >>Molecular content of the deposition flux during reactive Ar/O2 magnetron sputtering of Al
    2006 (English)In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 88, no 05, p. Art. No. 054101 JAN 30 2006-Article in journal (Refereed) Published
    Abstract [en]

    The deposition flux obtained during reactive radio frequency magnetron sputtering of an Al target in Ar/O2 gas mixtures was studied by mass spectrometry. The results show significant amounts of molecular AlO+ (up to 10% of the Al+ flux) in the ionic flux incident onto the substrate. In the presence of ~10–4 Pa H2O additional OH+ and AlOH+ were detected, amounting to up to about 100% and 30% of the Al+ flux, respectively. Since the ions represent a small fraction of the total deposition flux, an estimation of the neutral content was also made. These calculations show that, due to the higher ionization probability of Al, the amount of neutral AlO in the deposition flux is of the order of, or even higher than, the amount of Al. These findings might be of great aid when explaining the alumina thin film growth process.

    Place, publisher, year, edition, pages
    Institutionen för fysik, kemi och biologi, 2006
    Keywords
    alumina, dielectric thin films, sputter deposition, mass spectra
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-10452 (URN)10.1063/1.2170404 (DOI)
    Note
    Original publication: Andersson, J.M., Wallin, E., Münger, E.P. & Helmersson, U., Molecular content of the deposition flux during reactive Ar/O2 magnetron sputtering of Al, 2006, Applied Physics Letters, (88), 054101. http://dx.doi.org/10.1063/1.2170404. Copyright: American Institute of Physics, http://apl.aip.org/apl/top.jspAvailable from: 2007-12-17 Created: 2007-12-17 Last updated: 2017-12-14
    4. Effects of additives in α- and θ-alumina: an ab initio study
    Open this publication in new window or tab >>Effects of additives in α- and θ-alumina: an ab initio study
    2004 (English)In: Journal of Physics: Condensed Matter, ISSN 0953-8984, Vol. 16, no 49, p. 8971-8980Article in journal (Refereed) Published
    Abstract [en]

    It is of high fundamental and practical importance to be able to control the formation and stability of the different crystalline phases of alumina (Al2O3). In this study, we have used density functional theory methods to investigate the changes induced in the thermodynamically stable α phase and the metastable θ phase as one eighth of the Al atoms are substituted for different additives (Sc, W, Mo, Cr, Cu, Si, and B). The calculations predict that the additives strongly affect the relative stability between the two phases. Most tested additives are shown to shift the relative stability towards, and in some cases completely stabilize, the θ phase, while Cu doping is predicted to increase the relative stability of the α phase. The reasons for these effects are discussed, as are possible implications on the growth and use of doped aluminas in practical applications. In addition, the effects of the additives on bulk moduli and densities of states have been investigated.

    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-13581 (URN)10.1088/0953-8984/16/49/012 (DOI)
    Available from: 2005-12-13 Created: 2005-12-13 Last updated: 2013-10-30
    5. Ab initio calculations on the effects of additives on alumina phase stability
    Open this publication in new window or tab >>Ab initio calculations on the effects of additives on alumina phase stability
    Show others...
    2005 (English)In: Physical review. B, Condensed matter and materials physics, ISSN 1098-0121, Vol. 71, no 014101, p. 014101-Article in journal (Refereed) Published
    Abstract [en]

    The effects of substitutional additives on the properties and phase stability of - and -alumina (Al2O3), are investigated by density functional theory total energy calculations. The dopants explored are 5 at. % of Cr, Mo, Co, and As substituting for Al, respectively, N and S substituting for O, in the and lattices. Overall, the results show that it is possible to shift, and even reverse, the relative stability between - and -alumina by substitutional additives. The alumina bulk moduli are, in general, only slightly affected by the dopants but density of states profiles reveal additional peaks in the alumina band gaps. We also show that phase separations into pure oxides are energetically favored over doped alumina formation, and we present results on a number of previously unstudied binary oxides.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-13582 (URN)10.1103/PhysRevB.71.014101 (DOI)
    Available from: 2005-12-13 Created: 2005-12-13 Last updated: 2013-10-30
    6. Energy distributions of positive and negative ions during magnetron sputtering of an Al target in Ar/O2 mixtures
    Open this publication in new window or tab >>Energy distributions of positive and negative ions during magnetron sputtering of an Al target in Ar/O2 mixtures
    2006 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 100, no 3, p. Art. No. 033305 AUG 1 2006-Article in journal (Refereed) Published
    Abstract [en]

    The ion flux obtained during reactive magnetron sputtering of an Al target in Ar/O2 gas mixtures was studied by energy-resolved mass spectrometry, as a function of the total and O2 partial pressures. The positive ions of film-forming species exhibited bimodal energy distributions, both for direct current and radio frequency discharges, with the higher energy ions most likely originating from sputtered neutrals. For the negative oxygen ions a high-energy peak was observed, corresponding to ions formed at the target surface and accelerated towards the substrate over the sheath potential. As the total pressure was increased the high-energy peaks diminished due to gas-phase scattering. Based on these results, the role of energetic bombardment for the phase constituent of alumina thin films are discussed.

    Place, publisher, year, edition, pages
    College Park, MD, United States: American Institute of Physics (AIP), 2006
    Keywords
    aluminium, sputter deposition, diffusion, mass spectra, high-frequency discharges, plasma materials processing
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-10472 (URN)10.1063/1.2219163 (DOI)000239764100014 ()
    Note

    Original publication: Jon M. Andersson, E. Wallin, E. P. Münger & U. Helmersson, Energy distributions of positive and negative ions during magnetron sputtering of an Al target in Ar/O2 mixtures, 2006, Journal of Applied Physics, (100), 033305. http://dx.doi.org/10.1063/1.2219163. Copyright: American Institute of Physics, http://jap.aip.org/jap/top.jsp

    Available from: 2007-12-19 Created: 2007-12-19 Last updated: 2017-12-14
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  • 39.
    Andersson, Mari
    et al.
    Linköping University, Department of Management and Engineering, Carl Malmsten - furniture studies. Linköping University, The Institute of Technology.
    Rovin, Elin
    Linköping University, Department of Management and Engineering, Carl Malmsten - furniture studies. Linköping University, The Institute of Technology.
    Strukturer: Experiment med hantverkstekniker2012Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [sv]

    I vårt examensarbete har vi experimenterat medtraditionella hantverkstekniker i syfte att hitta nya sättatt använda oss av dem i inredningar och på möbler.Som tapetserare var vi intresserade av att utgå ifråndessa tekniker för att upptäcka nya sätt att skapaspännande strukturer i klädselarbetet på möbler.

    I den inledande delen går vi in på de frågor vi villundersöka samt vad som är målet med vårt arbete.Därefter följer huvuddelen där de praktiska testernaredovisas. Här har vi praktiskt testat och arbetatutifrån ett stort antal tekniker för att se vilka som harpotential att användas för vårt syfte. Dessa har tillstörsta delen varit väl beprövade hantverksteknikersom vi har försökt förnya till exempel genom attanvända oss av andra material än vad som vanligtvisanvänds, ändra dimension eller enbart genom attsätta in tekniken i ett nytt sammanhang. I denavslutande delen beskriver vi utvecklingen ochresultatet av ett fåtal tekniker som vi arbetat vidaremed. Vi avslutar med en sammanfattning och enreflekterande diskussion.

    Det har varit en otroligt spännande och kreativprocess som har utmynnat i många intressanta idéeroch objekt.

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    Elin Rovin & Mari Andersson
  • 40.
    Andersson, Markus
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Blomdahl, Rikard
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Adjusting route charges to increase profit2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Route charges are fees that airlines pay in order to utilize the Air Navigation Services (ANS) of a European state. The fee is based on three values; the weight of the aircraft, the length of the flight, and the state’s specific unit rate. The unit rate of each state is in turn based on the forecasted costs of providing ANS for that state and the amount of traffic forecasted for the year to come.

    This makes for different unit rates for different states, which leads to different costs for flying different routes in the European airspace. A state having costs that are increasing faster than the amount of traffic is increasing will lead to a higher unit rate. A higher unit rate may lead to airlines avoiding the state’s airspace due to higher costs, thus accounting for even less traffic and an increase in unit rate.

    This thesis examines the relationship between unit rate and amount of traffic, and specifically tries to find out how much the unit rate affects the traffic count. This has been done by reading previous papers on the subject, and creating a model to easily present facts found.

    The result of the thesis suggests that states actually profits more by increasing the unit rate rather than actively trying to reduce it. This contradicts the idea of lowering prices always being a good thing. There is a limit to how much the unit rate can be increases however, at which all traffic will choose to circumnavigate the airspace. Finding a good balance between traffic lost and unit rate increased is suggested as the best way to go.

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  • 41.
    Andersson, Matilda
    Linköping University, Department of Computer and Information Science, Human-Centered systems.
    Användarbehov och kontextuella krav för val av mobil interaktionsteknik: Behovs- och användarundersökning i Scanias verkstäder2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Mobil informationsteknik har på senaste tiden fått mer uppmärksamhet inom industriella applikationer, inte minst inom underhåll och reparation där teknisk dokumentation förekommer i stor utsträckning. Scania har tagit fram ett nytt koncept för interaktion med teknisk dokumentation i verkstaden där en viktig del av konceptet är mobilitet. Scanias förhoppningar är att en ökad möjlighet till mobilitet ska kunna förbättra användarupplevelsen.

    I detta arbete har en observationsstudie genomförts för att identifiera användarnas behov av mobilitet vid reparation och underhållsarbete samt de kontextuella faktorer som påverkar val av mobil interaktionsteknik.

    Fyra olika behov av mobilitet kunde identifieras efter analysen och till dessa kunde olika krav knytas för att skapa ett underlag för bedömning av olika teknikers potential att uppfylla de aktuella behoven.

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    Matilda Andersson - Användarbehov och kontextuella krav för val av mobil interaktionsteknik
  • 42.
    Andersson, Matilda
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Wandfelt, Fredrik
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Optimization of maintenance system2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report presents an optimization of the allocation of maintenance resources for Air Navigation Service (ANS) equipment of which LFV is responsible for the maintenance. The purpose the authors have worked after is to research ways of minimizing travelling time linked to maintenance visits for ANS equipment, this report includes the suggestions where the maintenance facilities should be placed in order to minimize the total travelling time. The report describes the problem background and presents the customer, LFV. It includes a chapter on some of the theories used for facility location and routing, and also presents methods for reducing the total travelling time used for maintenance visits annually. The authors have worked with a given set of airports in Sweden. Information about the general work with maintenance as well as the annual demand of maintenance, including the frequency of visits, for each airport included in this project was received by Pär Oberger, the task expert and contact at LFV for this report. A model for facility location based on the p-median model have been created and used when solving the problem, it was written in AMPL and solved with the CPLEX solver. The model was modified with two additional constraints regulating the minimum annual working time and the maximum distance for one-way travelling. The authors deems that a solution with five facilities is better since the benefit of additional facilities, in term of lower total distance, do not compensate for the assumed cost of establishing them.

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    fulltext
  • 43.
    Andersson, Mike
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Tailoring of SiC based field effect gas sensors for improved selectivity t non-hydrogen containing species2010In: IMCS13 2010, 2010, p. 369-Conference paper (Refereed)
  • 44.
    Andersson, Mike
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Sensor Science. Linköping University, The Institute of Technology.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Sensor Science. Linköping University, The Institute of Technology.
    Pearce, Ruth
    Linköping University, Department of Physics, Chemistry and Biology, Applied Sensor Science. Linköping University, The Institute of Technology. NPL, London from March 2012.
    Recent trends in Silicon Carbide (SiC) and Graphene based gas sensors2013In: Semiconductor Gas Sensors / [ed] R. Jaaniso and O. K. Tan, Woodhead Publishing Limited, 2013, p. 117-158Chapter in book (Refereed)
    Abstract [en]

    The introduction of silicon carbide (SiC) as the semiconductorin gas sensitive field effect devices has tremendously improved this sensor platform extending the temperature range and number of detectable gases. Here we review the recent trends in research, starting with transducer mechanisms, latest findings regarding the detection mechanism, and present new material combinations as sensing layers and smart operation of the field effect sensors enabling one sensor to act as a sensor array. Introducing epitaxially-grown graphene on SiC as gas sensing layer shows the potential of ppb detection of NO2 .

  • 45.
    Andersson, Mike
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Sensor and Actuator Systems. Linköping University, Faculty of Science & Engineering. University of Oulu, Finland.
    Möller, Peter
    Linköping University, Department of Physics, Chemistry and Biology, Sensor and Actuator Systems. Linköping University, Faculty of Science & Engineering.
    Fashandi, Hossein
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Eriksson, Jens
    Linköping University, Department of Physics, Chemistry and Biology, Sensor and Actuator Systems. Linköping University, Faculty of Science & Engineering.
    Puglisi, Donatella
    Linköping University, Department of Physics, Chemistry and Biology, Sensor and Actuator Systems. Linköping University, Faculty of Science & Engineering.
    Huotari, J.
    University of Oulu, Finland.
    Puustinen, J.
    University of Oulu, Finland.
    Lappalainen, J.
    University of Oulu, Finland.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Sensor and Actuator Systems. Linköping University, Faculty of Science & Engineering. University of Oulu, Finland.
    Field Effect Based Gas Sensors, from Basic Mechanisms to the Latest Commercial Device Designs2016In: SENSORS AND ELECTRONIC INSTRUMENTATION ADVANCES (SEIA), INT FREQUENCY SENSOR ASSOC-IFSA , 2016, p. 19-21Conference paper (Refereed)
    Abstract [en]

    This contribution treats the latest developments in the understanding of basic principles regarding device design, transduction mechanisms, gas-materials-interactions, and materials processing for the tailored design and fabrication of SiC FET gas sensor devices, mainly intended as products for the automotive sector.

  • 46.
    Andersson, Per
    Linköping University, Department of Management and Engineering.
    Radio Frequency Thermal Treatment of Liver Tumours: -Influence of Blood Perfusion and Large Vessels2008Independent thesis Advanced level (degree of Magister), 20 points / 30 hpStudent thesis
    Abstract [en]

    Radio frequency ablation (RFA) is a commonly used minimally invasive method of treating liver cancer tumours which utilises RF current for heating tumour tissue up to a lethal temperature. RF current is generated by a power generator and applied to the tumour by an electrode which is inserted into the tumour either during percutaneous or open surgery.

    RFA is a method that has great advantages compared to traditional surgical resection of tumours due to minimal invasiveness, it can be used for a greater number of patients and enables repeated treatments. Even though there are many advantages coupled to RFA there are still some problems and difficulties associated with the method. One of these problems is the cooling effect from large vessel blood flow within the liver, the so called heat sink effect.

    The aim of this master thesis work has been to develop a theoretical finite element model of RFA within Comsol Multiphysics software. This theoretical model has been used to simulate blood perfusion effects on resulting ablation volume. The effects from different large vessel blood flow parameters has been investigated, these parameters are: blood flow velocity, blood vessel diameter and distance between blood vessel and RF electrode. A factorial design has been utilised to setup parameter levels for the different simulations. A linear- and a second degree regression model has been calculated based on simulation results. The parameter with largest impact on simulative ablation volume and the interaction effects between the parameters were determined from the regression model coefficients. In addition to this has two simulations been performed, modelling perfused- and unperfused liver tissue, in order to investigate the effects resulting from microvascular perfusion.

    The result shows that the parameter with largest impact on simulative ablation volume are the distance, it was also shown that there are a small interactional effects between diameter and distance, where a small distance increases the effect from a varying diameter. Modelled microvascular perfusion was shown to give a decrease in simulative ablation volume. A shortage of this master thesis work is the lack of experimental verification of the developed model.

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    FULLTEXT01
  • 47. Andreasson, Martin
    et al.
    Karabag, Solmaz Filiz
    Simonsson, Johan
    Agarwal, Girish
    Dynamics of related and unrelated digital diversification in established firms: Strategies, programs, process, and outcomes2024In: Technological forecasting & social change, ISSN 0040-1625, E-ISSN 1873-5509, Vol. 202, p. 123300-123300, article id 123300Article in journal (Refereed)
    Abstract [en]

    Research on digital transformation focuses on business models and technological innovation but it often lacks a detailed exploration of how firms develop, execute, and evaluate related and unrelated digital diversification strategies. To address this gap, this study employs a multiple case study approach to uncover the varied processes and outcomes of implementing digital diversification programs in established firms. The findings reveal that established firms frequently refine and adjust their digital diversification strategies to achieve desired results. Specifically, related digital diversification strategies benefit from well-defined market segments, clear technological focus, and robust senior management support. In contrast, unrelated digital diversification strategies thrive through extensive exploration and experimentation with novel digital technologies and markets, reduced senior managerial intervention and increased middle- and lower-level management involvement. Semi-related digital diversification strategies, which incorporate elements of both related and unrelated approaches, often encounter tensions owing to conflicting traditional and new program execution methods, posing significant realization challenges. Key factors identified as instrumental in the success of digital diversification strategies include technology, markets, management & organization, and program execution. The study concludes by discussing the managerial and academic implications and offers recommendations for future research in this domain.

  • 48.
    Andreopoulou, Areti
    et al.
    National and Kapodistrian University of Athens.
    Walker, Bruce N.Georgia Institute of Technology.McMullen, KylaUniversity of Florida.Rönnberg, NiklasLinköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Safe and Sound: Proceedings of the 27th Annual International Conference on Auditory Display2022Conference proceedings (editor) (Refereed)
  • 49.
    Anund, Anna
    et al.
    Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Tapani, Andreas
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology. Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Chalkia, Eleni
    Centre of Research and Technology Hellas/Hellenic Institute of Transport, Thessaloniki, Greece.
    Watch Out! Something Precious is Moving2011In: Infrastructure and Safety in a Collaborative World: Road Traffic Safety / [ed] Evangelos Bekiaris, Marion Wiethoff, Evangelia Gaitanidou, Berlin Heidelberg: Springer Berlin/Heidelberg, 2011, 1, p. 233-242Chapter in book (Other academic)
    Abstract [en]

    One critical situation when a driver needs to have a high degree of awareness, to avoid critical situations or crashes, is when passing a school bus, stopped for boarding or de-boarding of children. With the help of an experiment in VTI’s moving base driving simulator, a scenario, using in-vehicle information before the bus was reached, was tested. The aim was to enhance drivers’ perception, in order to reduce the speed of vehicles passing by the stopped bus. Both alert and sleep deprived drivers were tested. The results showed a significant speed reduction thanks to the information given beforehand. Sleep deprivation did not seem to have an impact on speed reduction. This suggests that the warning signals are seen and followed, regardless the drivers’ state of alertness. Thus, it seems likely that this type of information may be useful as an Intelligent Transport System (ITS), to provide driver support about upcoming hazards. One step towards further research in this direction is performed within the EU project SAFEWAY2SCHOOL, the main objectives of which are presented at the end of this chapter.

  • 50.
    Arbring, Theresia
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    The impact of geometrical variations on the transport properties of organic electronic ion pumps2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The organic electronic ion pump (OEIP) is an electrically controlled polymer-based device that has the capability to interact with biological systems down to a single cell level by mimicking neural signalling. This is accomplished by translation of an electrical signal into a chemical output, such as ions and neurotransmitters. Because of the combined spatial and temporal precision, this is a technology with a promising future as an advanced therapeutic device. Depending on the application, the OEIP requires different geometries. Implants that will be used to control on a single cell level require very small dimensions, while for example extracorporeal mounted OIEPs, with only the delivery channel penetrating the skin, require much longer channels. Despite the application, it is necessary to have a good knowledge about the transport and delivery properties and how they change due to the geometry. These properties have been observed as very varying and unstable in early unpublished results, and these findings motivate this project. This project includes photolithographic fabrication and investigation of transport and delivery properties such as effective resistance, efficiency and stability of OEIPs with varying delivery channel lengths and widths. Shorter delivery channels show a consistent but relatively low efficiency. Delamination between different layers of the device is suspected as the cause. Initially, the longer delivery channels show a low functionality, most probably due to poor encapsulation. It is suggested that a soft, water-permeable plastic best encapsulates OEIPs that will be used as a medical implant, while a material impermeable to water, for example a metal, could successfully encapsulate OEIPs operating in air.

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