Browsing by Author "Andersson, Peter"

Filter results by typing the first few letters
Now showing 1 - 7 of 7
  • No Thumbnail Available
    Item
    Artighetsmarkörer? Om förstås och andra självklarhetsadverb
    (Humanistiska fakultetsnämnden vid Göteborgs universitet, 2002) Andersson, Peter
  • No Thumbnail Available
    Item
    Det förstås! Utvecklingen av svenska självklarhetsadverb under 1800- och 1900-talet
    (Institutionen för svenska språket, 2002-04) Andersson, Peter
  • No Thumbnail Available
    Item
    Grammaticalization meets construction grammar Opportunities, challenges and potential incompatibilities
    (2018) Coussé, Evie; Andersson, Peter; Olofsson, Joel
    Grammaticalization research has increasingly highlighted the notion of constructions in the last decade. In the wake of this heightened interest, efforts have been made in grammaticalization research to more precisely articulate the largely pretheoretical notion of construction in the theoretical framework of construction grammar. As such, grammaticalization research increasingly interacts and converges with the emerging field of diachronic construction grammar. This volume brings together articles that are situated at the intersection of grammaticalization research and diachronic construction grammar. All articles share an interest in integrating insights from grammaticalization research and construction grammar in order to advance our understanding of empirical cases of grammaticalization. Constructions at various levels of abstractness are investigated, both in well-documented languages, such as Ancient Greek, Latin, Spanish, German, Norwegian and English, and in less-described languages, such as Manchu and Mongolian.
  • No Thumbnail Available
    Item
  • No Thumbnail Available
    Item
    Monte Carlo and machine learning approach to in-vivo transmission dosimetry for dynamic radiation treatments
    (2025-04-17) Andersson, Peter
    In this thesis the main aim was to improve patient-specific quality assurance (QA) in external beam radiotherapy for dynamic techniques such as intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT) through the development of in vivo transmission dosimetry methods using the electronic portal imaging device (EPID). Five studies addressed interrelated challenges, ranging from the modelling of the radiation beam and dose calculations in the patient to the determination of post-treatment volume energy fluence and the prediction of transmission EPID images. In Study I an automated Monte Carlo (MC) system for pretreatment QA of VMAT, incorporating patient geometry and DICOM-compliant workflows was developed. A 3D dose comparison analysis software was developed and implemented together with diagnose-specific tolerance criteria for DVH parameters and 3D dose differences. Study II analysed MC-calculated lung dose sensitivity to tissue characterization during deep inspiration breath-hold (DIBH) for breast cancer treatments, identifying that very low-density lung regions require precise CT number to density conversion and tissue segmentation to avoid dose inaccuracies. Study III investigated the response of the CC13 ionization chamber under non-reference conditions, demonstrating its limited utility for narrow static fields but feasibility for dynamic, small-field geometries, provided measured and calculated doses agreed within 3% tolerance. Studies IV and V focused on EPID-based in vivo dosimetry. Study IV developed a hybrid MC and deep learning (DL) framework using U-Net architectures to predict EPID images from MC-generated exit phase space energy fluence data, demonstrating preliminary feasibility. Study V quantified EPID sensitivity to positional and material variations in a thorax phantom using gamma analysis and pixel difference histograms. While VMAT plans showed higher gamma passing rates than IMRT under positional errors, detection efficacy varied depending on error type and plan complexity. Collectively, this work proposes a strategy for in vivo EPID dosimetry combining MC-derived energy fluence predictions with DL-based image generation. The results highlight limitations in conventional QA methods, particularly for errors undetected by integrated dosimetry, and empha-size the need for robust error detection through post-patient energy fluence analysis. The devel-oped tools and methodologies propose a base for future work and clinical implementation.
  • No Thumbnail Available
    Item
    Sture Allén eller Big Brother-Linda – vem har makten över språkets förändring?
    (Humanistiska fakultetsnämnden vid Göteborgs universitet, 2004) Andersson, Peter; Bergström, Annika
  • No Thumbnail Available
    Item
    Vidta alla åtgärder som behövs – en rättvetenskaplig studie av arbetsgivarens ansvar att förebygga stressrelaterad ohälsa och uppnå en god psykosocial arbetsmiljö
    (2013-05-14) Andersson, Peter
    Prevention of stress related ill-health is one of the most important occupational health and safety issues of our time. The Swedish Work Environment Act imposes extensive requirements regarding the psychosocial work environment on the employer. The employer is obliged to take all precautions necessary to prevent ill-health, also such ill-health associated with stress at work. These requirements are enforced through rules regarding co-operation between employers and employees, rules of supervision from the Swedish Work Environment Authority and rules concerning criminal liability for work environment offences. The employer’s legal responsibility to prevent stress at work and injuries related to stress is thus, as a starting point, extensive. However, this responsibility is rarely demanded in legal practice. It has, for example, never yet occurred that an employer has been convicted of work environment offence for causing an employee stress related ill-health. This study deals with the employer's responsibility to prevent stress related ill-health and achieve a good psychosocial work environment from a broad legal perspective. The study covers the fundamental purposes and legal principles that permeate the regulation of the work environment and thereby affects the employer's responsibility to prevent stress. The requirements that the Work Environment Act impose on the employer through the rules concerning the state of the psychosocial work environment and the general preventive obligations are examined. Furthermore, the legal possibilities to demand responsibility for the psychosocial work environment according to the rules regarding co-operation, supervision and criminal responsibility are explored. The study demonstrates that the regulation is so vague in its design that the employer, in practice, is not given the possibility to achieve a clear understanding of what is required to prevent stress related ill-health. Therefore, introduction of clear binding provisions from the Work Environment Authority regarding the psychosocial work environment, to complement the general rules of the Work Environment Act, is proposed.