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  • 1.
    Himmelbach, Marc
    et al.
    Hertie-Institute for Clinical Brain Research, Eberhard Karls University, Tübingen, Germany.
    Böhme, Rebecca
    Hertie-Institute for Clinical Brain Research, Eberhard Karls University, Tübingen, Germany.
    Karnath, Hans-Otto
    Hertie-Institute for Clinical Brain Research, Eberhard Karls University, Tübingen, Germany.
    20 years later: A second look on DF’s motor behaviour2012In: Neuropsychologia, ISSN 0028-3932, E-ISSN 1873-3514, Vol. 50, no 1, p. 139-144Article in journal (Refereed)
    Abstract [en]

    The so-called action vs. perception model represents one of the currently dominating models addressing visual processing in primates. One of the crucial cornerstones of the action vs. perception model of visual processing is the dissociation of impaired perception versus intact visuomotor control in neurological patients with visual form agnosia (VFA). In fact, virtually all evidence related to VFA supporting the model was reported from only one patient: patient D.F. Through the last two decades D.F. became as important as only very few other exemplar cases in the neurosciences. However, a large corpus of experiments with this individual used methods that were insufficient to reveal less obvious impairments on a single subject level. We reanalysed the data of D.F. and identified basic visuomotor impairments that had been overlooked so far. Our reanalysis underlines the fact that the widespread and popular presentation of strong dissociations between distinct visual systems seems to be exaggerated.

  • 2.
    Turner, Anthony
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics.
    24th Anniversary World Congress on Biosensors – Biosensors 20142014Conference proceedings (editor) (Refereed)
    Abstract [en]

    Welcome to Biosensors 2014 and welcome to Melbourne, ranked as the world's most liveable city!

    This is the 24th anniversary edition of the World Congress on Biosensors and we continue to evolve, adapt and grow into new roles to serve the analytical needs of a rapidly changing society. Advances in telecommunications, expert systems and distributed diagnostics are prompting us to question the conventional ways we deliver healthcare, while robust industrial sensors are facilitating new paradigms in R&D and production. Personalisation of everything from medicine to environmental control, is giving new impetus to consumer choice and ownership of information, and will inevitably generate new payment structures and business models. Moreover, a deeper understanding of the bio/electronic interface leads us towards new horizons in areas such as bionics, power generation and computing.  Wearable, mobile and integrated sensors are becoming common place, but most current products have taken the easy path of incorporating physical sensors for parameters such as temperature, pressure, orientation or position. There is still a glaring absence of suitably robust and convenient commercial biosensors for body chemistries and ecosystems, and therein lies the real opportunities for progress.  We are a still-emerging technology that is fuelling scientific discovery and underpinning new products to enhance the length and quality of life.

    Always in a new country and always with fresh plenary speakers, we aim to reflect the latest and the best in Biosensors. This three-day event, organised by Elsevier in association with Biosensors & Bioelectronics, consists of two daily plenary presentations from leading figures in the field, followed by four parallel sessions, comprising a rigorously refereed selection of submitted papers. This year, we received 1,156 submissions of which 124 with be presented as regular Oral papers, with an additional 20 singled out as Invited talks and a further 12 selected for extended Keynote talks. The Keynote speakers have also been invited to submit full papers for consideration for the Biosensors and Bioelectronics Prize for the most original contribution to the Congress and the winners will be announced at the conference banquet on Thursday night. There will also be poster awards and you will find voting slips for each of the three days in your delegate bags. The winners of these awards and a prize draw, sponsored by Linköping University and Acreo Swedish ICT, will be announced at the closing ceremony on Friday. In order to enhance the valued medium of poster presentation, this year we have introduced a new Poster in my Pocket Ap.  Poster presenters have been able to upload a PDF of their poster prior to the conference to help increase the exposure of their work. This compliments the other new Ap introduced this year to place the full programme at your fingertips. Selected oral presentations will also have the opportunity to upload their talks online for future viewing.

    The academic programme, as usual, is enhanced by a fine collection of commercial exhibits and in addition to browsing their stands; you will be able to hear short elevator pitches during the breaks. We must thank our main commercial sponsor, Ercon for their generous and continued support of our congress. Thanks also to New Tools for Health for sponsoring the pre-congress Networking Event.  Now a regular feature for Biosensors, we have a pre-congress school, this year on Optical Biosensors, which is brought to you by Profs Fran Ligler and Tanya Monro. Last, but not least I must thank our marvellous Local Organising Committee chaired by Prof Justin Gooding, our hard working main Organising Committee, all the speakers and delegates, and the Elsevier team for all their support.

    Our delegates come from the four corners of the globe to hear the science, to grasp the opportunities and to meet the people; it’s going to be the best meeting yet. Enjoy and don’t forget to join us again in Gothenburg, Sweden, 24-27 May for Biosensor 2016!

  • 3.
    Skerfving Stål, Linda
    Linköping University, Department of Management and Engineering, Malmstens Linköping University.
    25 lika – 25 olika: – En undersökning i lasergraveringens möjligheter till att återge och skapa egna motiv och dekor på möbler i en nutida kontext2023Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    This work is a survey about the cabinetmakers possibilities to use laser engraving for personalised décor in furniture making. I have used analog and digital techniques in a way to take control over the end results of the laser engravings that I make from my patterns and motifs. My motifs and patterns are mainly constructed with a digital pen in a sketch program om my computer.

    Initially, I did a number of technical tests to learn about the different settings so that I later on could use them to my advantage when I created different motifs. After understanding most of the consequences of different settings I began to adapt my motifs with a conscious planning for how I could use the laser engraving settings to control the final result. In some cases, I have also done some after work in the form of pyrographing or Dremel engraving by hand. Much more are to be desired of those results. My conclusion is that the best results I got were when I used the laser engraving to complete my motifs the way visual artists use their brush, which is what I learned during my work.

    In addition to the practical work, I have also tried to make a theoretical reasoning about decór and ornament historically and where I fit in today.

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  • 4.
    Hallert, Eva
    et al.
    Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Rehabilitation Center. Linköping University, Department of Medical and Health Sciences, Health Technology Assessment and Health Economics.
    Husberg, Magnus
    Linköping University, Department of Medical and Health Sciences, Health Technology Assessment and Health Economics. Linköping University, Faculty of Health Sciences.
    Skogh, Thomas
    Linköping University, Department of Clinical and Experimental Medicine, Rheumatology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Rheumatology.
    28-joint count disease activity score at 3 months after diagnosis of early rheumatoid arthritis is strongly associated with direct and indirect costs over the following 4 years: the Swedish TIRA project2011In: Rheumatology, ISSN 1462-0324, E-ISSN 1462-0332, Vol. 50, no 7, p. 1259-1267Article in journal (Refereed)
    Abstract [en]

    Methods. Three-hundred and twenty patients with early (1 year) RA were assessed at regular intervals. Clinical and laboratory data were collected and patients reported health-care utilization and number of days lost from work. At 3-month follow-up, patients were divided into two groups according to disease activity, using DAS-28 with a cut-off level at 3.2. Direct and indirect costs and EuroQol-5D over the following 4 years were compared between the groups. Multivariate regression models were used to control for possible covariates. Results. Three months after diagnosis, a DAS-28 level of epsilon 3.2 was associated with high direct and indirect costs over the following 4 years. Patients with DAS-28 epsilon 3.2 at 3-month follow-up had more visits to physician, physiotherapist, occupational therapist and nurse, higher drug costs, more days in hospital and more extensive surgery compared with patients with 3-month DAS-28 less than 3.2. Number of days lost from work due to sick leave and permanent work disability was also higher in this group. The effect of disease activity on health-related quality of life was highly significant. In regression models, DAS-28 at 3-month follow-up was significantly associated with costs over the following years. Conclusions. Three months after diagnosis, DAS-28 is an important prognostic marker regarding health-care utilization and costs. Achieving remission or low disease activity 3 months after diagnosis is likely to decrease morbidity, increase quality of life and save costs for the patient and for society over the following years.

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  • 5. 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
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  • 6.
    Karlsson, John
    Linköping University, Department of Computer and Information Science, Human-Centered systems.
    2D Beats: Fast paced full body movement game using Godot Engine2022Independent thesis Basic level (university diploma), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The world is quickly moving to a more and more digital world, everything is online and computerized. This is convenient but also increases the amount of time spent in front of various types of devices and displays, not getting the exercise we as humans need. Gaming or the act of playing video games is very much a part of this and is traditionally thought of as a sedentary activity. However, there is a type of video games that does not fall into this category, that is exergames. Exergames distinguish themselves from sedentary games in that they use the human body for control, leading to their use to combat the lack of exercise. This thesis describes the implementation and testing of one such exergame that is a part of a larger project at Linköping University that aims to create a library of games to be used in organizations where sitting for long periods is common. The game is implemented using the game engine Godot and an ML solution called MediaPipe for movement tracking and recognition. The goal was to create an easy to playgame providing moderate to high physical activity. Testing showed that the game provided the desired physical exertion within a few consecutive rounds and exertion remained on roughly the same level even if the user was experienced. 

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  • 7.
    Shtepliuk, Ivan
    Linköping University, Department of Physics, Chemistry and Biology, Semiconductor Materials. Linköping University, Faculty of Science & Engineering.
    2D noble metals: growth peculiarities and prospects for hydrogen evolution reaction catalysis2023In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 25, no 12, p. 8281-8292Article in journal (Refereed)
    Abstract [en]

    High-performance electrocatalysts for the hydrogen evolution reaction are of interest in the development of next-generation sustainable hydrogen production systems. Although expensive platinum-group metals have been recognized as the most effective HER catalysts, there is an ongoing requirement for the discovery of cost-effective electrode materials. This paper reveals the prospects of two-dimensional (2D) noble metals, possessing a large surface area and a high density of active sites available for hydrogen proton adsorption, as promising catalytic materials for water splitting. An overview of the synthesis techniques is given. The advantages of wet chemistry approaches for the growth of 2D metals over deposition techniques show the potential for kinetic control that is required as a precondition to prevent isotropic growth. An uncontrolled presence of surfactant-related chemicals on a 2D metal surface is however the main disadvantage of kinetically controlled growth methods, which stimulates the development of surfactant-free synthesis approaches, especially template-assisted 2D metal growth on non-metallic substrates. Recent advances in the growth of 2D metals using a graphenized SiC platform are discussed. The existing works in the field of practical application of 2D noble metals for hydrogen evolution reaction are analyzed. This paper shows the technological viability of the "2D noble metals" concept for designing electrochemical electrodes and their implementation into future hydrogen production systems, thereby providing an inspirational background for further experimental and theoretical studies.

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  • 8.
    Qu, Jianxin
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Kunnappallil, Nikil Johny
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    2D Orientation Estimation Using Machine Learning With Multiple 5G Base Stations2022Independent thesis Advanced level (degree of Master (Two Years)), 28 HE creditsStudent thesis
    Abstract [en]

    Localization of mobile devices has implications on a multitude of use cases such as estimating the location of the user originating an emergency call, localization of devices to enable autonomous operation required by industrial Internet of Things (IoT) use cases, etc. In futuristic use cases such as Augmented Reality (AR), Virtual Reality (VR), Extended Reality (XR), autonomous navigation of Unmanned Aerial Vehicles (UAVs), we will require the capability of estimating orientation in addition to position of such devices for efficient and effective provisioning of these services to the end-users.

    One way to handle the problem of finding the orientation of devices is to rely on the measurements from different sensors like the magnetometer, accelerometer and gyroscope but the limitation of this method is the dependency on these sensors, and thus cannot be used for some devices which does not have these sensors. Hence these limitations can be overcome by using data-driven approaches like Machine Learning (ML) algorithms on received signal features, where a training dataset with orientation measurements are used to train the ML model that can transform the received signal measurements to orientation estimates.

    The data for the work is generated by using simulator that can simulate the environment with multiple base stations and receivers. The measurements or features that are generated from the simulator are the Received Signal Received Power (RSRP), Time of Arrival (ToA), Line of Sight (LoS) condition, etc. In-order to find the relationship between the received signal features and orientation, two nonlinear ML algorithms namely K Nearest Neighbors (KNN) and Random Forest (RF) are used. The received measurements were investigated and RSRP was identified as the feature for the ML models.

    The ML algorithms are able to estimate the orientation of the User Equipment (UE) by using KNN and RF, where different features likes RSRP and the information about LoS and Non Line of Sight (NLoS). These features were used alone and also combined to evaluate the performance. The results also shows how interference of radio signals affects the performance of the model. Adding to that, different combination of received signal features were also used to compare the performance of the model. Further tests were also done on the trained model to identify how well it can estimate orientation when a new UE with new position is introduced.

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  • 9.
    Grönwall, Christina
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Gustafsson, Fredrik
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    3D Content-Based Model Matching using Geometric Features2006Report (Other academic)
    Abstract [en]

    We present an approach that utilizes efficient geometric feature extraction and a matching method that takes articulation into account. It is primarily applicable for man-made objects. First the object is analyzed to extract geometric features, dimensions and rotation are estimated and typical parts, so-called functional parts, are identified. Examples of functional parts are a box's lid, a building's chimney, or a battle tank's barrel. We assume a model library with full annotation. The geometric features are matched with the model descriptors, to gain fast and early rejection of non-relevant models. After this pruning the objectis matched with relevant, usually few, library models. We propose a sequential matching, where the number of functional parts increases in each iteration. The division into parts increases the possibility for correct matching result when several similar models are available. The approach is exemplifi…ed with an vehicle recognition application, where some vehicles have functional parts.

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  • 10.
    Ekström, Joakim
    Linköping University, Department of Electrical Engineering, Automatic Control.
    3D Imaging Using Photon Counting Lidar on a Moving Platform2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The problem of constructing high quality point clouds based on measurements from a moving and rotating single-photon counting lidar is considered in this report. The movement is along a straight rail while the lidar sensor rotates side to side. The point clouds are constructed in three steps, which are all studied in this master’s thesis. First, point clouds are constructed from raw lidar measurements from single sweeps with the lidar. In the second step, the sensor transformation between the point clouds constructed in the first step are obtained in a registration step using iterative closest point (ICP). In the third step the point clouds are combined to a coherent point cloud, using the full measurement. A method using simultaneous localization and mapping (SLAM) is developed for the third step. It is then compared to two other methods, constructing the final point cloud only using the registration, and to utilize odometric information in the combination step. It is also investigated which voxel discretization that should be used when extracting the point clouds.

    The methods developed are evaluated using experimental data from a prototype photon counting lidar system. The results show that the voxel discretization need to be at least as large as the range quantization in the lidar. No significant difference between using registration and SLAM in the third step is observed, but both methods outperform the odometric method.

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  • 11.
    Dahlin, Johan
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    3D Modeling of Indoor Environments2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With the aid of modern sensors it is possible to create models of buildings. These sensorstypically generate 3D point clouds and in order to increase interpretability and usability,these point clouds are often translated into 3D models.In this thesis a way of translating a 3D point cloud into a 3D model is presented. The basicfunctionality is implemented using Matlab. The geometric model consists of floors, wallsand ceilings. In addition, doors and windows are automatically identified and integrated intothe model. The resulting model also has an explicit representation of the topology betweenentities of the model. The topology is represented as a graph, and to do this GraphML isused. The graph is opened in a graph editing program called yEd.The result is a 3D model that can be plotted in Matlab and a graph describing the connectivitybetween entities. The GraphML file is automatically generated in Matlab. An interfacebetween Matlab and yEd allows the user to choose which rooms should be plotted.

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  • 12.
    Falk, Martin
    et al.
    VISUS - Visualization Research Center, Universität Stuttgart, Germany.
    Klann, Michael
    Institute of Biochemical Engineering and Center Systems Biology, Universität Stuttgart, Germany.
    Reuss, Matthias
    Institute of Biochemical Engineering and Center Systems Biology, Universität Stuttgart, Germany.
    Ertl, Thomas
    VISUS - Visualization Research Center, Universität Stuttgart, Germany.
    3D Visualization of Concentrations from Stochastic Agent-based Signal Transduction Simulations2010In: Biomedical Imaging: From Nano to Macro, 2010 IEEE International Symposium on: From Nano to Macro (ISBI 2010), IEEE, 2010, p. 1301-1304Conference paper (Refereed)
    Abstract [en]

    Cellular signal transduction involves a transport step from the plasma membrane towards the nucleus, during which the signaling molecules are partly deactivated in control loops. This leads to a gradient in the concentration of active signaling molecules. The low number of molecules introduces spatio-temporal fluctuations and the asymmetric cellular architecture further increases the complexity. We propose a technique to represent this pattern in a continuous three-dimensional concentration map. The local concentration is computed and visualized with volume rendering techniques at interactive frame rates and is therefore well-suited for time-dependent data. Our approach allows the transition from the nano-scale of single and discrete signaling proteins to a continuous signal on the cell level. In the application context of this paper, we employ an agent-based Monte Carlo simulation to calculate the actual particle positions depending on reaction and transport parameters in the cell. The applicability of the proposed technique is demonstrated by an investigation of the effects of different transport parameters in Mitogen-activated protein kinase (MAPK) signaling.

  • 13.
    Sörliden, Pär
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    3D Visualization of MPC-based Algorithms for Autonomous Vehicles2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The area of autonomous vehicles is an interesting research topic, which is popular in both research and industry worldwide. Linköping university is no exception and some of their research is based on using Model Predictive Control (MPC) for autonomous vehicles. They are using MPC to plan a path and control the autonomous vehicles. Additionally, they are using different methods (for example deep learning or likelihood) to calculate collision probabilities for the obstacles. These are very complex algorithms, and it is not always easy to see how they work. Therefore, it is interesting to study if a visualization tool, where the algorithms are presented in a three-dimensional way, can be useful in understanding them, and if it can be useful in the development of the algorithms. 

    This project has consisted of implementing such a visualization tool, and evaluating it. This has been done by implementing a visualization using a 3D library, and then evaluating it both analytically and empirically. The evaluation showed positive results, where the proposed tool is shown to be helpful when developing algorithms for autonomous vehicles, but also showing that some aspects of the algorithm still would need more research on how they could be implemented. This concerns the neural networks, which was shown to be difficult to visualize, especially given the available data. It was found that more information about the internal variables in the network would be needed to make a better visualization of them.

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  • 14.
    Mirman, Zachary
    et al.
    Laboratory for Cell Biology and Genetics, Rockefeller University, New York, NY, USA..
    Lottersberger, Francisca
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Laboratory for Cell Biology and Genetics, Rockefeller University, New York, NY, USA..
    Takai, Hiroyuki
    Laboratory for Cell Biology and Genetics, Rockefeller University, New York, NY, USA..
    Kibe, Tatsuya
    Laboratory for Cell Biology and Genetics, Rockefeller University, New York, NY, USA..
    Gong, Yi
    Laboratory for Cell Biology and Genetics, Rockefeller University, New York, NY, USA..
    Takai, Kaori
    Laboratory for Cell Biology and Genetics, Rockefeller University, New York, NY, USA..
    Bianchi, Alessandro
    Laboratory for Cell Biology and Genetics, Rockefeller University, New York, NY, USA.; Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, UK..
    Zimmermann, Michal
    Laboratory for Cell Biology and Genetics, Rockefeller University, New York, NY, USA.; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada..
    Durocher, Daniel
    Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada..
    de Lange, Titia
    Laboratory for Cell Biology and Genetics, Rockefeller University, New York, NY, USA. delange@rockefeller.edu..
    53BP1-RIF1-shieldin counteracts DSB resection through CST- and Polα-dependent fill-in.2018In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 560, no 7716, p. 112-116Article in journal (Refereed)
    Abstract [en]

    In DNA repair, the resection of double-strand breaks dictates the choice between homology-directed repair-which requires a 3' overhang-and classical non-homologous end joining, which can join unresected ends1,2. BRCA1-mutant cancers show minimal resection of double-strand breaks, which renders them deficient in homology-directed repair and sensitive to inhibitors of poly(ADP-ribose) polymerase 1 (PARP1)3-8. When BRCA1 is absent, the resection of double-strand breaks is thought to be prevented by 53BP1, RIF1 and the REV7-SHLD1-SHLD2-SHLD3 (shieldin) complex, and loss of these factors diminishes sensitivity to PARP1 inhibitors4,6-9. Here we address the mechanism by which 53BP1-RIF1-shieldin regulates the generation of recombinogenic 3' overhangs. We report that CTC1-STN1-TEN1 (CST)10, a complex similar to replication protein A that functions as an accessory factor of polymerase-α (Polα)-primase11, is a downstream effector in the 53BP1 pathway. CST interacts with shieldin and localizes with Polα to sites of DNA damage in a 53BP1- and shieldin-dependent manner. As with loss of 53BP1, RIF1 or shieldin, the depletion of CST leads to increased resection. In BRCA1-deficient cells, CST blocks RAD51 loading and promotes the efficacy of PARP1 inhibitors. In addition, Polα inhibition diminishes the effect of PARP1 inhibitors. These data suggest that CST-Polα-mediated fill-in helps to control the repair of double-strand breaks by 53BP1, RIF1 and shieldin.

  • 15.
    Malmström, Magnus
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Skog, Isaac
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Modarres Razavi, Sara
    Ericsson Research, Sweden.
    Zhao, Yuxin
    Ericsson Research, Sweden.
    Gunnarsson, Fredrik
    Ericsson Research, Sweden.
    5G Positioning: A Machine Learning Approach2019In: 2019 16th Workshop on Positioning, Navigation and Communications (WPNC), IEEE, 2019Conference paper (Refereed)
    Abstract [en]

    In urban environments, cellular network-based positioning of user equipment (UE) is a challenging task, especially in frequently occurring non-line-of-sight (NLOS) conditions. This paper investigates the use of two machine learning methods – neural networks and random forests – to estimate the position of UE in NLOS using best received reference signal beam power measurements. We evaluated the suggested positioning methods using data collected from a fifth-generation cellular network (5G) testbed provided by Ericsson. A statistical test to detect NLOS conditions with a probability of detection that is close to 90% is suggested. We show that knowledge of the antenna are crucial for accurate position estimation. In addition, our results show that even with a limited set of training data and one 5G transmission point, it is possible to position UE within 10 meters with 80% accuracy.

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  • 16.
    Malmström, Magnus
    Linköping University, Department of Electrical Engineering, Automatic Control.
    5G Positioning using Machine Learning2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Positioning is recognized as an important feature of fifth generation (\abbrFiveG) cellular networks due to the massive number of commercial use cases that would benefit from access to position information. Radio based positioning has always been a challenging task in urban canyons where buildings block and reflect the radio signal, causing multipath propagation and non-line-of-sight (NLOS) signal conditions. One approach to handle NLOS is to use data-driven methods such as machine learning algorithms on beam-based data, where a training data set with positioned measurements are used to train a model that transforms measurements to position estimates. 

    The work is based on position and radio measurement data from a 5G testbed. The transmission point (TP) in the testbed has an antenna that have beams in both horizontal and vertical layers. The measurements are the beam reference signal received power (BRSRP) from the beams and the direction of departure (DOD) from the set of beams with the highest received signal strength (RSS). For modelling of the relation between measurements and positions, two non-linear models has been considered, these are neural network and random forest models. These non-linear models will be referred to as machine learning algorithms. 

    The machine learning algorithms are able to position the user equipment (UE) in NLOS regions with a horizontal positioning error of less than 10 meters in 80 percent of the test cases. The results also show that it is essential to combine information from beams from the different vertical antenna layers to be able to perform positioning with high accuracy during NLOS conditions. Further, the tests show that the data must be separated into line-of-sight (LOS) and NLOS data before the training of the machine learning algorithms to achieve good positioning performance under both LOS and NLOS conditions. Therefore, a generalized likelihood ratio test (GLRT) to classify data originating from LOS or NLOS conditions, has been developed. The probability of detection of the algorithms is about 90\% when the probability of false alarm is only 5%. 

    To boost the position accuracy of from the machine learning algorithms, a Kalman filter have been developed with the output from the machine learning algorithms as input. Results show that this can improve the position accuracy in NLOS scenarios significantly.

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    5G Positioning using Machine Learning
  • 17.
    Jarvholm, Kajsa
    et al.
    SKane Univ Hosp, Sweden; Univ Gothenburg, Sweden.
    Bruze, Gustaf
    Karolinska Inst, Sweden.
    Peltonen, Markku
    Natl Inst Hlth and Welf, Finland.
    Marcus, Claude
    Karolinska Inst, Sweden.
    Flodmark, Carl-Erik
    Lund Univ, Sweden.
    Henfridsson, Pia
    Univ Gothenburg, Sweden.
    Beamish, Andrew J.
    Univ Gothenburg, Sweden; Royal Coll Surgeons England, England.
    Gronowitz, Eva
    Univ Gothenburg, Sweden.
    Dahlgren, Jovanna
    Univ Gothenburg, Sweden; Sahlgrens Univ Hosp, Sweden.
    Karlsson, Jan
    Orebro Univ, Sweden.
    Olbers, Torsten
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Norrköping. Univ Gothenburg, Sweden.
    5-year mental health and eating pattern outcomes following bariatric surgery in adolescents: a prospective cohort study2020In: LANCET CHILD and ADOLESCENT HEALTH, ISSN 2352-4642, Vol. 4, no 3, p. 210-219Article in journal (Refereed)
    Abstract [en]

    Background Mental health problems are prevalent among adolescents with severe obesity, but long-term mental health outcomes after adolescent bariatric surgery are not well known. We aimed to assess mental health outcomes over 5 years of follow-up after Roux-en-Y gastric bypass surgery in adolescents who participated in the Adolescent Morbid Obesity Surgery (AMOS) study. Methods This was a non-randomised matched-control study in adolescents aged 13-18 years who had a BMI of 40 kg/m(2) or higher, or 35 kg/m(2) or higher in addition to obesity-related comorbidity; who had previously undergone failed comprehensive conservative treatment; and were of pubertal Tanner stage III or higher, with height growth velocity beyond peak. A contemporary control group, matched for BMI, age, and sex, who underwent conventional obesity treatment, was obtained from the Swedish Childhood Obesity Treatment Register. Data on dispensed psychiatric drugs and specialist treatment for mental disorders were retrieved from national registers with complete coverage. In the surgical group only, questionnaires were used to assess self-esteem (Rosenberg Self-Esteem [RSE] score), mood (Mood Adjective Checklist [MACL]), and eating patterns (Binge Eating Scale [BES] and Three-Factor Eating Questionnaire-R21 [TFEQ]). This study is registered with ClinicalTrials.gov (NCT00289705). Findings Between April 10, 2006, and May 20, 2009, 81 adolescents (53 [65%] female) underwent Roux-en-Y gastric bypass surgery, and 80 control participants received conventional treatment. The proportion of participants prescribed psychiatric drugs did not differ between groups in the years before study inclusion (pre-baseline; absolute risk difference 5% [95% CI -7 to 16], p=0.4263) or after intervention (10% [-6 to 24], p=0.2175). Treatment for mental and behavioural disorders did not differ between groups before baseline (2% [-10 to 14], p=0.7135); however, adolescents in the surgical group had more specialised psychiatric treatment in the 5 years after obesity treatment than did the control group (15% [1 to 28], p=0.0410). There were few patients who discontinued psychiatric treatment post-surgery (three [4%] receiving psychiatric drug treatment and six [7%] receiving specialised care for a mental disorder before surgery). In the surgical group, self-esteem (RSE score) was improved after 5 years (mixed model mean 21.6 [95% CI 19.9 to 23.4]) relative to baseline (18.9 [17.4 to 20.4], p=0.0059), but overall mood (MACL score) was not (2.8 [2.7 to 2.9] at 5 years vs 2.7 [2.6 to 2.8] at baseline, p=0.0737). Binge eating was improved at 5 years (9.3 [7.4 to 11.2]) relative to baseline (15.0 [13.5 to 16.5], pamp;lt;0.0001). Relative changes in BMI were not associated with the presence or absence of binge eating at baseline. Interpretation Mental health problems persist in adolescents 5 years after bariatric surgery despite substantial weight loss. Although bariatric surgery can improve many aspects of health, alleviation of mental health problems should not be expected, and a multidisciplinary bariatric team should offer long-term mental health support after surgery. Copyright (C) 2020 Elsevier Ltd. All rights reserved.

  • 18.
    Kihlman, Henrik
    et al.
    Linköping University, Department of Mechanical Engineering. Linköping University, The Institute of Technology.
    Loser, Raimund
    Leica Geosystems AG.
    6DOF metrology-integrated robot control2003Conference paper (Refereed)
    Abstract [en]

    This paper describes ongoing research into Metrology-integrated robot control. The research is a part of an ongoing EU funded aircraft industry project – ADFAST*. The ADFAST project tries to implement the use of industrial robots in low-volume production, high-demand-on-accuracy operations and for dynamic force compensation. To detect and compensate deflection in industrial robots during a process, the robot uses a metrology system. The metrology system supervises the tool center point of the robot as it executes its processes. Leica has recently released a new metrology system; the LTD800, which measures distances with laser interferometry and can simultaneously measure orientation of targets, through photogrammetry, using an additional camera on top of the measuring unit. This paper will describe theory and results from tests performed on integrating the LTD800 with the robot.

  • 19.
    Heimann, Mikael
    et al.
    University of Bergen, Norway.
    Nilheim, Katarina
    Göteborg University, Sweden.
    6-month-olds and delayed actions: An early sign of an early explicit memory?2004In: Cogniţie, Creier, Comportament/Cognition, Brain, Behavior, ISSN 1224-8398, Vol. VIII, no 3-4, p. 249-254Article in journal (Refereed)
    Abstract [en]

    In 1996 Barr, Dowden and Hayne reported that 6 month old infants imitate new actions with objects after a substantial delay. This is a finding in need of independent replications and the study reported here presents one such attempt. Forty-five 6 months old Swedish infants (22 girls) participated in the study. They were randomly assigned to either an experimental (n=30) or acontrol condition (n=15). The procedure replicates the method used by Barret al. with one exception: The imposed delay was 10 minutes instead of 24 hours. Overall it was found that the children in the imitation group displayed significantly more target acts than the children in the control group and it is concluded that infants are capable of using deferred imitation as means for learning new actions already at 6 months.

  • 20.
    Zhang, Dai
    et al.
    Linköping University, Department of Electrical Engineering. Linköping University, Faculty of Science & Engineering. Catena Wireless Elect AB, Sweden.
    Alvandpour, Atila
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    A 12.5-ENOB 10-kS/s Redundant SAR ADC in 65-nm CMOS2016In: IEEE Transactions on Circuits and Systems - II - Express Briefs, ISSN 1549-7747, E-ISSN 1558-3791, Vol. 63, no 3, p. 244-248Article in journal (Refereed)
    Abstract [en]

    This brief describes a 14-b 10-kS/s successive approximation register analog-to-digital converter (ADC) for biomedical applications. In order to achieve enhanced linearity, a uniform-geometry nonbinary-weighted capacitive digital-to-analog converter is implemented. In addition, a secondary-bit approach to dynamically shift decision levels for error correction is employed. To reduce the power consumption, the ADC also features a power-optimized comparator with bias control. Prototyped in a 65-nm CMOS process, the ADC consumes 1.98 mu W and provides an effective number of bit (ENOB) of 12.5 b at 0.8 V while occupying an active area of 0.28 mm(2).

  • 21.
    Nyström, Christine Delisle
    et al.
    Novum, Sweden; Childrens Hosp, Canada.
    Sandin, Sven
    Karolinska Inst, Sweden; Icahn Sch Med Mt Sinai, NY 10029 USA; Seaver Autism Ctr Res and Treatment Mt Sinai, NY 10029 USA.
    Henriksson, Pontus
    Novum, Karolinska Institutet, Sweden; PROFITH, University Granada, Spain.
    Henriksson, Hanna
    Univ Granada, Spain.
    Maddison, Ralph
    Deakin Univ, Australia.
    Löf, Marie
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences. Novum, Karolinska Institutet, Sweden.
    A 12-month follow-up of a mobile-based (mHealth) obesity prevention intervention in pre-school children: the MINISTOP randomized controlled trial2018In: BMC Public Health, E-ISSN 1471-2458, Vol. 18, article id 658Article in journal (Refereed)
    Abstract [en]

    Background: To date, few mobile health (mHealth) interventions aimed at changing lifestyle behaviors have measured long term effectiveness. At the 6-month follow-up the MINISTOP trial found a statistically significant intervention effect for a composite score comprised of fat mass index (FMI) as well as dietary and physical activity variables; however, no intervention effect was observed for FMI. Therefore, the aim of this study was to investigate if the MINISTOP intervention 12-months after baseline measurements: (i) improved FMI and (ii) had a maintained effect on a composite score comprised of FMI and dietary and physical activity variables. Methods: A two-arm parallel randomized controlled trial was conducted in 315 healthy 4.5 year old children between January 2014 and October 2015. Parents of the participating children either received the MINISTOP intervention or a basic pamphlet on dietary and physical activity behaviors (control group). After 6 months, participants did not have access to the intervention content and were measured again 6 months later (i.e. the 12-month follow-up). The Wilcoxon rank-sum test was then used to examine differences between the groups. Results: At the 12-month follow-up, no statistically significant difference was observed between the intervention and control groups for FMI (p = 0.57) and no maintained effect for the change in composite score was observed (mean +/- standard deviation for the intervention and control group: + 0.53 +/- 1.49 units and + 0.35 +/- 1.27 units respectively, p = 0.25 between groups). Conclusions: The intervention effect observed at the 6-month follow-up on the composite score was not maintained at the 12-month follow-up, with no effect on FMI being observed at either follow-up. Future studies using mHealth are needed to investigate how changes in obesity related markers in young children can be maintained over longer time periods.

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  • 22.
    Kifle, Yonatan Habteslassie
    et al.
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering. Khalifa Univ Sci and Technol, U Arab Emirates.
    Alhawari, Mohammad
    Khalifa Univ Sci and Technol, U Arab Emirates; Wayne State Univ, MI 48202 USA.
    Bou-Sleiman, Sleiman
    Intel Corp, AZ USA.
    Saleh, Hani
    SoC Ctr, U Arab Emirates.
    Mohammad, Baker
    SoC Ctr, U Arab Emirates.
    Ismail, Mohammed
    Khalifa Univ Sci and Technol, U Arab Emirates; Wayne State Univ, MI 48202 USA.
    A 230 mu W built-in on-chip auto-calibrating RF amplitude detector in 65 nm CMOS2019In: Analog Integrated Circuits and Signal Processing, ISSN 0925-1030, E-ISSN 1573-1979, Vol. 101, no 2, p. 175-185Article in journal (Refereed)
    Abstract [en]

    In this paper, a built-in-self-calibration RF amplitude detector circuit in 65 nm CMOS is presented. The proposed architecture makes use of two detector replicas with a feedback control system to perform the self-calibration. The system is capable of detecting RF peak amplitudes range of 0-0.6 V-p with a conversion gain of - 3 V/V. The proposed system has a wide dynamic range that can auto-corrects the RF detector to less than 10% across process and temperature variations. This architecture is implemented in standard 65 nm 1P7 M CMOS process. Comprehensive silicon measurement results show that the self-calibration structure improves the detection error of the non-calibrated RF amplitude detector by a maximum of 71% at only 230 mu W overall power consumption. The proposed system can be used to calibrate the variations in circuits within an RF transceiver such as LNA, Mixers, oscillators etc.

  • 23.
    Wedajo, W.
    et al.
    Armauer Hansen Research InstituteAddis Ababa, Ethiopia; Department of Biology, Jimma UniversityJimma, Ethiopia.
    Schön, Thomas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Department of Infectious Diseases and Microbiology, Kalmar County HospitalKalmar, Sweden.
    Bedru, A.
    Armauer Hansen Research InstituteAddis Ababa, Ethiopia.
    Kiros, T.
    Armauer Hansen Research InstituteAddis Ababa, Ethiopia.
    Hailu, E.
    Armauer Hansen Research Institute Addis Ababa, Ethiopia.
    Mebrahtu, T.
    Armauer Hansen Research Institute Addis Ababa, Ethiopia.
    Yamuah, L.
    Armauer Hansen Research Institute Addis Ababa, Ethiopia.
    Angeby, K.
    Department of Clinical Microbiology MTC, Karolinska Hospital, Karolinska University HospitalStockholm, Sweden.
    Werngren, J.
    Department of Preparedness, Unit of Highly Pathogenic Microorganisms, Swedish Institute for Communicable Disease Control (SMI)Solna, Sweden.
    Onyebujoh, P.
    World Health Organization, Regional Office for Africa, Inter-country Support Team for East0/Southern AfricaHarare, Zimbabwe.
    Dagne, K.
    Addis Ababa University, Faculty of Life SciencesAddis Ababa, Ethiopia.
    Aseffa, A.
    Armauer Hansen Research Institute Addis Ababa, Ethiopia.
    A 24-well plate assay for simultaneous testing of first and second line drugs against Mycobacterium tuberculosis in a high endemic setting2014In: BMC Research Notes, E-ISSN 1756-0500, Vol. 7, no 1, p. 512-Article in journal (Refereed)
    Abstract [en]

    Background: Early detection of drug resistance is one of the priorities of tuberculosis (TB) control programs as drug resistance is increasing. New molecular assays are only accessible for a minority of the second line drugs and their availability in high endemic settings is also hampered by high cost and logistic challenges. Therefore, we evaluated a previously developed method for drug susceptibility testing (DST) including both first- and second line anti-TB drugs for use in high endemic areas. Results: Baseline mycobacterial isolates from 78 consecutive pulmonary TB patients from Addis Ababa, Ethiopia who were culture positive for Mycobacterium tuberculosis at the end of a two-month directly observed treatment short course (DOTS) were included. The isolates were simultaneously tested for isoniazid, rifampicin, ethambutol, streptomycin, amikacin, kanamycin, capreomycin, ofloxacin, moxifloxacin, ethionamide and para-aminosalicylic acid susceptibility using the indirect proportion method adopted for 24-well agar plates containing Middlebrook 7H10 medium. Applying the 24-well plate assay, 43 (55.1%) isolates were resistant to one or more of the first line drugs tested (isoniazid, rifampicin and ethambutol). MDR-TB was identified in 20.5% of this selected group and there was a perfect correlation for rifampicin resistance with the results from the genotype MTBDRplus assay. All isolates were susceptible to aminoglycosides and fluoroquinolones in agreement with the genotype MTBDRsl assay. The only tested second line drug associated to resistance was ethionamide (14.1% resistant). The method was reproducible with stable results for internal controls (one multi-drug resistant (MDR) and one pan-susceptible strain (H37Rv) and DST results could be reported at two weeks. Conclusions: The 24-well plate method for simultaneous DST for first- and second line drugs was found to be reproducible and correlated well to molecular drug susceptibility tests. It is likely to be useful in high-endemic areas for surveillance as well as for the detection of second line drug resistance in targeted groups such as in those who fail empirical MDR treatment.

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  • 24.
    Sundström, Timmy
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Electrical Engineering, Electronic Devices.
    Alvandpour, Atila
    Linköping University, The Institute of Technology. Linköping University, Department of Electrical Engineering, Electronic Devices.
    A 2.5-GS/s 30-mW 4-bit flash ADC in 90nm CMOS2008In: NORCHIP, IEEE , 2008, p. 264-267Conference paper (Refereed)
    Abstract [en]

    A 2.5 GS/s flash ADC, fabricated in 90 nm CMOS, avoids traditional power, speed and accuracy trade-offs by using comparator redundancy with power-gating capabilities. Redundancy removes the need to control comparator offsets, allowing the large process-variation induced mismatch of small devices in nanometer technologies. This enables the use of small-sized, ultra-low-power comparators. Measurement results show that the ADC dissipates 30 mW at 1.2 V. With 63 gate-able comparators, the ADC achieves 4.0 effective number of bits.

  • 25.
    Clark, Charlotte
    et al.
    Queen Mary University of London, England .
    Sörqvist, Patrik
    Linköping University, Faculty of Arts and Sciences. Linköping University, Department of Behavioural Sciences and Learning.
    A 3 year update on the influence of noise on performance and behavior2012In: Noise & Health, ISSN 1463-1741, E-ISSN 1998-4030, Vol. 14, no 61, p. 292-296Article in journal (Refereed)
    Abstract [en]

    The effect of noise exposure on human performance and behavior continues to be a focus for research activities. This paper reviews developments in the field over the past 3 years, highlighting current areas of research, recent findings, and ongoing research in two main research areas: Field studies of noise effects on childrens cognition and experimental studies of auditory distraction. Overall, the evidence for the effects of external environmental noise on childrens cognition has strengthened in recent years, with the use of larger community samples and better noise characterization. Studies have begun to establish exposure-effect thresholds for noise effects on cognition. However, the evidence remains predominantly cross-sectional and future research needs to examine whether sound insulation might lessen the effects of external noise on childrens learning. Research has also begun to explore the link between internal classroom acoustics and childrens learning, aiming to further inform the design of the internal acoustic environment. Experimental studies of the effects of noise on cognitive performance are also reviewed, including functional differences in varieties of auditory distraction, semantic auditory distraction, individual differences in susceptibility to auditory distraction, and the role of cognitive control on the effects of noise on understanding and memory of target speech materials. In general, the results indicate that there are at least two functionally different types of auditory distraction: One due to the interruption of processes (as a result of attention being captured by the sound), another due to interference between processes. The magnitude of the former type is related to individual differences in cognitive control capacities (e.g., working memory capacity); the magnitude of the latter is not. Few studies address noise effects on behavioral outcomes, emphasizing the need for researchers to explore noise effects on behavior in more detail.

  • 26.
    Zhang, Dai
    et al.
    Linköping University, Department of Electrical Engineering, Electronic Devices.
    Alvandpour, Atila
    Linköping University, Department of Electrical Engineering, Electronic Devices.
    A 3-nW 9.1-ENOB SAR ADC at 0.7 V and 1 kS/s2013Conference paper (Other academic)
    Abstract [en]

    This paper presents a 10-bit SAR ADC in 65 nm CMOS for medical implant applications. The ADC consumes 3-nW power and achieves 9.1 ENOB at 1 kS/s. The ultra-low-power consumption is achieved by using an ADC architecture with maximal simplicity, a small split-array capacitive DAC, a bottom-plate sampling approach reducing charge injection error and allowing full-range input sampling without extra voltage sources, and a latch-based SAR control logic resulting in reduced power and low transistor count. Furthermore, a multi-Vt circuit design approach allows the ADC to meet the target performance with a single supply voltage of 0.7 V. The ADC achieves a FOM of 5.5 fJ/conversion-step. The INL and DNL errors are 0.61 LSB and 0.55 LSB, respectively.

  • 27.
    Zhang, Dai
    et al.
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    Alvandpour, Atila
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    A 3-nW 9.1-ENOB SAR ADC at 0.7 V and 1 kS/s2012In: ESSCIRC, 2012, Institute of Electrical and Electronics Engineers , 2012, p. 369-372Conference paper (Refereed)
    Abstract [en]

    This paper presents a 10-bit SAR ADC in 65 nm CMOS for medical implant applications. The ADC consumes 3-nW power and achieves 9.1 ENOB at 1 kS/s. The ultra-low-power consumption is achieved by using an ADC architecture with maximal simplicity, a small split-array capacitive DAC, a bottom-plate sampling approach reducing charge injection error and allowing full-range input sampling without extra voltage sources, and a latch-based SAR control logic resulting in reduced power and low transistor count. Furthermore, a multi-Vt circuit design approach allows the ADC to meet the target performance with a single supply voltage of 0.7 V. The ADC achieves a FOM of 5.5 fJ/conversion-step. The INL and DNL errors are 0.61 LSB and 0.55 LSB, respectively.

  • 28.
    Lindgren, Christer
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Sinnescentrum, Department of Oral Surgery UHL.
    Mordenfeld, Arne
    Department of Oral and Maxillofacial Surgery, Gävle, County Hospital, Sweden/Dept of Biomaterials, Institute of Clinical Sciences, Göteborg University, Sweden.
    Johansson, CB
    School of Health and Medical Sciences, Örebro University, Örebro, Sweden.
    Hallman, Mats
    Department of Oral and Maxillofacial Surgery, Gävle, County Hospital, Sweden/Department of Oral & Maxillofacial Surgery, Umeå University, Umeå Sweden and Center for Research and Development, Uppsala University/Gävleborg County Council, Sweden.
    A 3-year clinical follow-up of implants placed in 2 differentbiomaterials used for sinus augmentationManuscript (preprint) (Other academic)
    Abstract [en]

    Purpose: The aims of the present study were to compare a novel biphasic calcium phosphate (BCP) with deproteinized bovine bone (DBB) used for maxillary sinus floor augmentation (MSFA) in a split mouth design, and to perform a clinical follow-up of placed dental implants.

    Material and Methods: Nine completely edentulous patients and two partially edentulous patients with a mean age of 67 years requiring bilateral sinus augmentation were included in the study. The patients were randomized for augmentation with BCP (test) and DBB (control) in the contralateral side. After 8 months of graft healing, 62 implants with an SLActive® surface (Strauman®, Basel, Switzerland) were placed. After 3 years of graft healing core biopsies were obtained from the grafted areas for histological and histomorphometrical analysis. After 3 years of functional implant loading, implant survival/success rate, clinical indexes, radiographical examination and resonance frequency analysis (RFA) wereperformed.

    Results: The mean values of the area of newly formed bone in the biopsies was 29% ±14.3% and 32% ± 18.0% for BCP and DBB respectively and graft particles in contact with bone in the BCP group was 38% ± 10.9% compared to 44% ± 12.1% for the DBB group, showing no significant differences between the groups. The mean values of the area of BCP particles and DBB particles were 20% ± 7.5% and 24% ± 13.5% respectively (non-significant).

    Irrespective of particles used, one dental implant was lost from each group, giving an overall implant survival rate of 96.8% after 3-years of loading. Conclusion: The results of this prospective 3-year clinical and histological follow up demonstrated a similar amount of newly formed bone irrespectively of the used biomaterial. The choice of biomaterial does not seem to influence the survival rates of the implants.

  • 29.
    Lindgren, Christer
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Sinnescentrum, Department of Oral Surgery UHL.
    Mordenfeld, Arne
    Gävle County Hospital, Sweden Gothenburg University, Sweden .
    Johansson, Carina B
    University of Örebro, Sweden .
    Hallman, Mats
    Gävle County Hospital, Sweden Umeå University, Sweden Uppsala University, Sweden .
    A 3-Year Clinical Follow-up of Implants Placed in Two Different Biomaterials Used for Sinus Augmentation2012In: International Journal of Oral & Maxillofacial Implants, ISSN 0882-2786, E-ISSN 1942-4434, Vol. 27, no 5, p. 1151-1162Article in journal (Refereed)
    Abstract [en]

    Purpose: The aims of the present study were to compare a novel biphasic calcium phosphate (BCP) with deproteinized bovine bone (DBB) for maxillary sinus floor augmentation in a split-mouth design and to perform a clinical follow-up of dental implants placed in the augmented sinuses. Materials and Methods: Partially or completely edentulous patients requiring bilateral sinus augmentation were included in the study. The patients were randomized for augmentation with BCP (test) and DBB (control) in the contralateral side. Eight months after grafting, dental implants were placed. After 3 years of graft healing, core biopsy specimens were obtained from the grafted areas for histologic and histomorphometric analyses. After 3 years of functional implant loading, implant survival/success rates and clinical indices were assessed and radiographic examination and resonance frequency analysis were performed. Results: Nine completely edentulous patients and two partially edentulous patients (mean age, 67 years) who required bilateral sinus augmentation were included in the study, and 62 implants were placed. The mean values for the area of newly formed bone in the retrieved specimens were 29% +/- 14.3% and 32% +/- 18.0% for BCP and DBB, respectively; the percentage of graft particles in contact with bone was 38% +/- 10.9% in the BCP group and 44% +/- 12.1% in the DBB group (no statistical significant differences between groups). The mean values for the area of BCP particles and DBB particles were 20% +/- 7.5% and 24% +/- 13.5%, respectively (difference not significant). One dental implant was lost from each group, resulting in an overall implant survival rate of 96.8% after 3 years of loading. Conclusion: After 3 years, a similar amount of newly formed bone was present regardless of the biomaterial used. The choice of biomaterial did not seem to influence implant survival rates.

  • 30.
    Garrido Gálvez, Mario
    et al.
    Linköping University, Department of Electrical Engineering, Computer Engineering. Linköping University, Faculty of Science & Engineering.
    Angel Sanchez, Miguel
    University of Politecn Madrid, Spain.
    Luisa Lopez-Vallejo, Maria
    University of Politecn Madrid, Spain.
    Grajal, Jesus
    University of Politecn Madrid, Spain.
    A 4096-Point Radix-4 Memory-Based FFT Using DSP Slices2017In: IEEE Transactions on Very Large Scale Integration (vlsi) Systems, ISSN 1063-8210, E-ISSN 1557-9999, Vol. 25, no 1, p. 375-379Article in journal (Refereed)
    Abstract [en]

    This brief presents a novel 4096-point radix-4 memory-based fast Fourier transform (FFT). The proposed architecture follows a conflict-free strategy that only requires a total memory of size N and a few additional multiplexers. The control is also simple, as it is generated directly from the bits of a counter. Apart from the low complexity, the FFT has been implemented on a Virtex-5 field programmable gate array (FPGA) using DSP slices. The goal has been to reduce the use of distributed logic, which is scarce in the target FPGA. With this purpose, most of the hardware has been implemented in DSP48E. As a result, the proposed FPGA is efficient in terms of hardware resources, as is shown by the experimental results.

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  • 31.
    Sundström, Timmy
    et al.
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    Alvandpour, Atila
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    A 4-bit 2.5-GS/s 30-mW Flash ADC in 90nm CMOS2009In: Swedish System on Chip Conference, SSoCC, Arild, May 4-5, Lunds universitet, 2009Conference paper (Other academic)
    Abstract [en]

    A 2.5 GS/s flash ADC, fabricated in 90nm CMOS,avoids traditional power, speed and accuracy trade-offs by usingcomparator redundancy with power-gating capabilities.Redundancy removes the need to control comparator offsets,allowing the large process-variation induced mismatch of smalldevices in nanometer technologies. This enables the use of smallsized,ultra-low-power comparators. Measurement results showthat the ADC dissipates 30 mW at 1.2 V. With 63 gate-ablecomparators, the ADC achieves 4.0 effective number of bits.

  • 32.
    Sundström, Timmy
    et al.
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    Alvandpour, Atila
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    A 6‐bit 2.5‐GS/s Flash ADC using Comparator Redundancy for Low Power in 90nm CMOS2010In: Analog Integrated Circuits and Signal Processing, ISSN 0925-1030, E-ISSN 1573-1979, Vol. 64, no 3, p. 215-222Article in journal (Refereed)
    Abstract [en]

    A 2.5 GS/s flash ADC, fabricated in 90nm CMOS utilizes comparator redundancy to avoid traditional power, speed and accuracy trade‐offs. The redundancy removes the need to control comparator offsets, allowing the large process‐variation induced mismatch of small devices in nanometer technologies. This enables the use of small‐sized, ultra‐low‐power comparators with clock‐gating capabilities in order to reduce the power dissipation. The chosen calibration method enables an overall low‐power solution and measurement results show that the ADC dissipates 30 mW at 1.2 V. With 63 comparators, the ADC achieves 3.9 effective number of bits.

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  • 33.
    Colombo, Armando Walter
    et al.
    Univ Appl Sci Emden Leer, Germany; Univ Appl Sci Emden Leer, Germany; IEEE Ind Elect Soc IES, Canada.
    Karnouskos, Stamatis
    IEEE, Canada.
    Yu, Xinghuo
    RMIT Univ, Australia.
    Kaynak, Okyay
    IEEE, Canada.
    Luo, Ren C.
    Natl Taiwan Univ, Taiwan.
    Shi, Yang
    IEEE, Canada; Univ Victoria, Canada.
    Leitao, Paulo
    IEEE, Canada; Polytech Inst Braganca, Portugal.
    Ribeiro, Luis
    Linköping University, Department of Management and Engineering, Manufacturing Engineering. Linköping University, Faculty of Science & Engineering. IEEE, Canada.
    Haase, Jan
    IEEE, Canada; Nordakademie Univ Appl Sci, Germany.
    A 70-Year Industrial Electronics Society Evolution Through Industrial Revolutions: The Rise and Flourishing of Information and Communication Technologies2021In: IEEE Industrial Electronics Magazine, ISSN 1932-4529, E-ISSN 1941-0115, Vol. 15, no 1, p. 115-126Article in journal (Refereed)
    Abstract [en]

    The Industrial Revolution, which originally involved the change from an agrarian and handicraft economy to a market dominated by factory mechanization during the early 18th century, has profoundly shaped the world. It has progressed through four disruptive phases: Industry 1.0 through Industry 4.0. Industry 1.0 encompassed early automation, while Industry 2.0 began at the end of the 19th century, when enormous technological advances were made, such as mass production, electrification, and new modes of transportation. Industry 3.0 began during the 1970s, a decade that gave rise to the electronics, telecommunications, and computing that enable full automation and robotics. Industry 4.0 kicked off at the dawn of the third millennium, marked by the ubiquitous use of Internet technologies, which have radically transformed how people, society, and industry interact.

  • 34.
    Härkegård, Ola
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Glad, Torkel
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Backstepping Design for Flight Path Angle Control2000In: Proceedings of the 39th IEEE Conference on Decision and Control, 2000, p. 3570-3575Conference paper (Refereed)
    Abstract [en]

    A nonlinear approach to flight path angle control is presented. Using backstepping, a globally stabilizing control law is derived. Although the nonlinear nature of the lift force is considered, the pitching moment to be produced is only linear in the measured states. Thus, the resulting control law is much simpler than if feedback linearization had been used. The free parameters that spring from the backstepping design are used to achieve a desired linear behavior around the operating point.

  • 35.
    Härkegård, Ola
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Glad, Torkel
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Backstepping Design for Flight Path Angle Control2000Report (Other academic)
    Abstract [en]

    A nonlinear approach to flight path angle control is presented. Using backstepping, a globally stabilizing control law is derived. Although the nonlinear nature of the lift force is considered, the pitching moment to be produced is only linear in the measured states. Thus, the resulting control law is much simpler than if feedback linearization had been used. The free parameters that spring from the backstepping design are used to achieve a desired linear behavior around the operating point.

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  • 36.
    Mahmoud, Nawrous Ibrahim
    Linköping University, Department of Electrical Engineering.
    A Backstepping Design of a Control System for a Magnetic Levitation System2003Independent thesis Basic level (professional degree)Student thesis
    Abstract [en]

    The subject of this thesis is the design of a control law for a magnetic levitation system, which in this case is the system 33-210. The method used is backstepping technique and specifically adaptive observer backstepping due to parameter uncertainties and lack of access to all the states of the system. The second state of the system, the speed of the steel ball, was estimated by a reduced order observer. The model used gave us the opportunity to estimate a parameter which in the literature is denoted virtual control coefficient. Backstepping method gives us a rather straight forward way to design the controlling unit for a system with these properties. Stabilization of the closed-loop system is achieved by incorporating a Lypapunov function, which were chose a quadratic one in this thesis. If thederivative of this function is rendered negative definite by the control law, then we achieve stability. The results of the design were evaluated in simulations and real-time measurements by testing the tracking performance of the system. The simulation results were very promising and the validations in real-time were satisfying. Note that this has been done in previous studies; the new aspect here is the limitation of the voltage input. The real-time results showed that the parameter estimation converges only locally.

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  • 37.
    Hu, Xiao-Li
    et al.
    China Jiliang University, China.
    Schön, Thomas
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Ljung, Lennart
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Basic Convergence Result for Particle Filtering2007In: Proceedings of the 7th IFAC Symposium on Nonlinear Control Systems, 2007, p. 288-293Conference paper (Refereed)
    Abstract [en]

    The basic nonlinear filtering problem for dynamical systems is considered. Approximating the optimal filter estimate by particle filter methods has become perhaps the most common and useful method in recent years. Many variants of particle filters have been suggested, and there is an extensive literature on the theoretical aspects of the quality of the approximation. Still, a clear cut result that the approximate solution, for unbounded functions, converges to the true optimal estimate as the number of particles tends to infinity seems to be lacking. It is the purpose of this contribution to give such a basic convergence result.  

  • 38.
    Hu, Xiao-Li
    et al.
    Chinese Academy of Sciences, China.
    Schön, Thomas
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Ljung, Lennart
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Basic Convergence Result for Particle Filtering2007Report (Other academic)
    Abstract [en]

    The basic nonlinear filtering problem for dynamical systems is considered. Approximating the optimal filter estimate by particle filter methods has become perhaps the most common and useful method in recent years. Many variants of particle filters have been suggested, and there is an extensive literature on the theoretical aspects of the quality of the approximation. Still a clear cut result that the approximate solution, for unbounded functions, converges to the true optimal estimate as the number of particles tends to infinity seems to be lacking. It is the purpose of this contribution to give such a basic convergence result for a rather general class of unbounded functions. Furthermore, a general framework, including many of the particle filter algorithms as special cases, is given.

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  • 39.
    Hu, Xiao-Li
    et al.
    Chinese Academy of Sciences, China.
    Schön, Thomas
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Ljung, Lennart
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Basic Convergence Result for Particle Filtering2007Report (Other academic)
    Abstract [en]

    The basic nonlinear filtering problem for dynamical systems is considered. Approximating the optimal filter estimate by particle filter methods has become perhaps the most common and useful method in recent years. Many variants of particle filters have been suggested, and there is an extensive literature on the theoretical aspects of the quality of the approximation. Still a clear cut result that the approximate solution, for unbounded functions, converges to the true optimal estimate as the number of particles tends to infinity seems to be lacking. It is the purpose of this contribution to give such a basic convergence result for a rather general class of unbounded functions. Furthermore, a general framework, including many of the particle filter algorithms as special cases, is given.

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  • 40.
    Hu, Xiao-Li
    et al.
    Chinese Academy of Sciences, China.
    Schön, Thomas
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Ljung, Lennart
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Basic Convergence Result for Particle Filtering2008In: IEEE Transactions on Signal Processing, ISSN 1053-587X, E-ISSN 1941-0476, Vol. 56, no 4, p. 1337-1348Article in journal (Refereed)
    Abstract [en]

    The basic nonlinear filtering problem for dynamical systems is considered. Approximating the optimal filter estimate by particle filter methods has become perhaps the most common and useful method in recent years. Many variants of particle filters have been suggested, and there is an extensive literature on the theoretical aspects of the quality of the approximation. Still a clear-cut result that the approximate solution, for unbounded functions, converges to the true optimal estimate as the number of particles tends to infinity seems to be lacking. It is the purpose of this contribution to give such a basic convergence result for a rather general class of unbounded functions. Furthermore, a general framework, including many of the particle filter algorithms as special cases, is given.

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  • 41.
    Özkan, Emre
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Lundquist, Christian
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Gustafsson, Fredrik
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Bayesian Approach to Jointly Estimate Tire Radii and Vehicle Trajectory2011In: Proceedings of the International IEEE Conference on Intelligent Transportation Systems, Washington DC, USA: IEEE conference proceedings, 2011, p. 1-6Conference paper (Refereed)
    Abstract [en]

    High-precision estimation of vehicle tire radii is considered, based on measurements on individual wheel speeds and absolute position from a global navigation satellite system (GNSS). The wheel speed measurements are subject to noise with time-varying covariance that depends mainly on the road surface. The novelty lies in a Bayesian approach to estimate online the time-varying radii and noise parameters using a marginalized particle filter, where no model approximations are needed such as in previously proposed algorithms based on the extended Kalman filter. Field tests show that the absolute radius can be estimated with millimeter accuracy, while the relative wheel radius on one axle is estimated with submillimeter accuracy.

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  • 42.
    Isaksson, Alf
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Gustafsson, Fredrik
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Bayesian Approach to Manoeuvre Tracking and Detection1993In: Proceedings of the 12th IFAC World Congress, 1993Conference paper (Refereed)
  • 43.
    Isaksson, Alf
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Gustafsson, Fredrik
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Bayesian Approach to Manoeuvre Tracking and Detection1992Report (Other academic)
  • 44.
    Gharaee, Zahra
    et al.
    Linköping University, Department of Electrical Engineering, Computer Vision. Linköping University, Faculty of Science & Engineering.
    Holmquist, Karl
    Linköping University, Department of Electrical Engineering, Computer Vision. Linköping University, Faculty of Science & Engineering.
    He, Linbo
    Linköping University, Department of Electrical Engineering, Computer Vision. Linköping University, Faculty of Science & Engineering.
    Felsberg, Michael
    Linköping University, Department of Electrical Engineering, Computer Vision. Linköping University, Faculty of Science & Engineering.
    A Bayesian Approach to Reinforcement Learning of Vision-Based Vehicular Control2021In: 2020 25TH INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION (ICPR), IEEE COMPUTER SOC , 2021, p. 3947-3954Conference paper (Refereed)
    Abstract [en]

    In this paper, we present a state-of-the-art reinforcement learning method for autonomous driving. Our approach employs temporal difference learning in a Bayesian framework to learn vehicle control signals from sensor data. The agent has access to images from a forward facing camera, which are pre-processed to generate semantic segmentation maps. We trained our system using both ground truth and estimated semantic segmentation input. Based on our observations from a large set of experiments, we conclude that training the system on ground truth input data leads to better performance than training the system on estimated input even if estimated input is used for evaluation. The system is trained and evaluated in a realistic simulated urban environment using the CARLA simulator. The simulator also contains a benchmark that allows for comparing to other systems and methods. The required training time of the system is shown to be lower and the performance on the benchmark superior to competing approaches.

  • 45.
    Bergman, Niclas
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Bayesian Approach to Terrain-Aided Navigation1997In: Proceedings of the 11th IFAC Symposium on System Identification, 1997, p. 1531-1536Conference paper (Refereed)
    Abstract [en]

    The terrain-aided navigation problem is a highly nonlinear estimation problem with application to aircraft navigation and missile guidance. In this work the Bayesian approach is used to estimate the aircraft position. With a quantization of the state space an implementable algorithm is found. Problems with low excitation, rough terrain and parallel position hypothesis are handled in a reliable way. The algorithm is evaluated using simulations on real terrain databases.

  • 46.
    Bergman, Niclas
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Bayesian Approach to Terrain-Aided Navigation1996Report (Other academic)
    Abstract [en]

    The terrain-aided navigation problem is a highly nonlinear estimation problem with application to aircraft navigation and missile guidance. In this work the Bayesian approach is used to estimate the aircraft position. With a quantization of the state space an implementable algorithm is found. Problems with low excitation, rough terrain and parallel position hypothesis are handled in a reliable way. The algorithm is evaluated using simulations on real terrain databases.

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  • 47.
    Bergman, Niclas
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Bayesian Approach to Terrain-Aided Navigation II1997Report (Other academic)
    Abstract [en]

    The terrain-aided navigation problem is a highly nonlinear estimation problem with application to aircraft navigation and missile guidance. In this work the Bayesian approach is used to estimate the aircraft position. With a quantization of the state space an implementable algorithm is found. Problems with low excitation, rough terrain and parallel position hypothesis are handled in a reliable way. The algorithm is evaluated using simulations on real terrain databases.

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    A Bayesian Approach to Terrain-Aided Navigation II
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  • 48.
    Lindström, Tom
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering. Colorado State University, CO 80523 USA; US National Institute Heatlh, MD USA; University of Exeter, England.
    Tildesley, Michael
    US National Institute Heatlh, MD USA; University of Nottingham, England.
    Webb, Colleen
    Colorado State University, CO 80523 USA; US National Institute Heatlh, MD USA.
    A Bayesian Ensemble Approach for Epidemiological Projections2015In: PloS Computational Biology, ISSN 1553-734X, E-ISSN 1553-7358, Vol. 11, no 4, p. e1004187-Article in journal (Refereed)
    Abstract [en]

    Mathematical models are powerful tools for epidemiology and can be used to compare control actions. However, different models and model parameterizations may provide different prediction of outcomes. In other fields of research, ensemble modeling has been used to combine multiple projections. We explore the possibility of applying such methods to epidemiology by adapting Bayesian techniques developed for climate forecasting. We exemplify the implementation with single model ensembles based on different parameterizations of the Warwick model run for the 2001 United Kingdom foot and mouth disease outbreak and compare the efficacy of different control actions. This allows us to investigate the effect that discrepancy among projections based on different modeling assumptions has on the ensemble prediction. A sensitivity analysis showed that the choice of prior can have a pronounced effect on the posterior estimates of quantities of interest, in particular for ensembles with large discrepancy among projections. However, by using a hierarchical extension of the method we show that prior sensitivity can be circumvented. We further extend the method to include a priori beliefs about different modeling assumptions and demonstrate that the effect of this can have different consequences depending on the discrepancy among projections. We propose that the method is a promising analytical tool for ensemble modeling of disease outbreaks.

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  • 49.
    Solaki, Eleni
    Linköping University, Department of Culture and Society.
    A begging permit, a ban or something else?: The construction of mobile poor and begging as a 'problem' in three Swedish municipalities2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    More and more Swedish municipalities are adopting approaches that target ‘vulnerable EU citizens’ and the ‘passive collection of money’. This thesis analyses begging permits, bans, and other approaches, motivated by the positions supported in Eskilstuna, Katrineholm and Norrköping. The approaches analysed are irrespective of the municipalitiesthat implemented them. This thesis follows a ‘problem’ questioning approach, taking into consideration the context and the system under which the ‘problems’ are constructed and aims to find the implicit and explicit aims of the various approaches.

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  • 50.
    Moberg, Stig
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Öhr, Jonas
    ABB AB, Crane Systems, Sweden.
    Gunnarsson, Svante
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Benchmark Problem for Robust Control of a Multivariable Nonlinear Flexible Manipulator2008In: Proceedings of the 17th IFAC World Congress, 2008, p. 1206-1211Conference paper (Refereed)
    Abstract [en]

    A benchmark problem for robust feedback control of a manipulator is presented. The system to be controlled is an uncertain nonlinear two link manipulator with elastic gear transmissions. The gear transmission is described by nonlinear friction and elasticity. The system is uncertain according to a parametric uncertainty description and due to uncertain disturbances affecting both the motors and the tool. The system should be controlled by a discrete-time controller that optimizes performance for given robustness requirements. The control problem concerns only disturbance rejection. The proposed model is validated by experiments on a real industrial manipulator.

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