Publikationer från Högskolan i Gävle
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Instanssegmentering av körskador i skogsbruket med Mask R-CNN och drönarbilder
No full textTunga skogsmaskiner orsakar betydande markskador vid avverkning, vilket påverkar skogens ekologi och produktivitet negativt. Identifiering och kartläggning av dessa körskador är avgörande för hållbar skogsförvaltning, men traditionella fältinventeringar är tidskrävande och ineffektiva. Denna studie undersöker möjligheten att använda Mask R-CNN för att identifiera och segmentera körskador i drönarbilder från skogsavverkningsområden i Gävleborgs län. Mask R-CNN är en avancerad djupinlärningsmodell för instanssegmentering, baserad på convolutional neural network (CNN). Studien syftar till att undersöka Mask R-CNN:s potential i denna kontext, samt analysera hur klassdefinitioner och efterbearbetning påverkar resultaten. Två olika klassindelningar undersöktes: en indelning med separata klasser för körskador med och utan vatten, samt en indelning där dessa behandlades som en enhetlig klass. Dessutom utvärderades effekten av efterbearbetning som eliminerar överlapp mellan maskprediktioner. Metoden innefattar annotering och förbehandling av högupplösta RGB-drönarbilder, dataaugmentation och en detaljerad träningsstrategi med regelbunden validering. Modellens prestanda utvärderades både kvantitativt, genom precision, återkallning, F1-värde och total noggrannhet, och kvalitativt genom visuell analys av segmenteringsresultat. Resultaten visade att Mask R-CNN effektivt identifierar körskador. Klassindelningen hade viss påverkan på segmenteringsprestandan: indelning av körskador som en enhetlig klass presterade bäst vid maskbaserad utvärdering, med ett F1-värde på 0,74 och 0,725 före respektive efter efterbearbetning. Den pixelbaserade utvärderingen visade att klassindelningarna gav jämförbar prestanda: med ett F1-värde på 0,782 och 0,786 samt total noggrannhet på 0,947 och 0,948, för enhetlig respektive uppdelad klassindelning. Efterbearbetningen eliminerade överlapp mellan predikterade masker avsevärt och förbättrade den visuella tydligheten utan att påverka de kvantitativa mätvärdena nämnvärt. Studien drar slutsatsen att Mask R-CNN kan bidra till effektivare och mer hållbar skogsförvaltning genom snabbare och mindre resurskrävande identifiering av körskador. Heavy forestry machinery causes significant soil damage, particularly in the form of wheel ruts, during logging operations. These damages negatively impact forest ecology and productivity. Identifying and mapping such wheel ruts is crucial for sustainable forest management, but traditional field surveys are time-consuming and inefficient. This study explores the potential of using Mask R-CNN to detect and segment wheel rut damage in drone imagery from logging areas in Gävleborg County. Mask R-CNN is an advanced deep learning model for instance segmentation, based on convolutional neural networks (CNN). The aim of the study is to evaluate the model’s potential in this context and to analyze how class definitions and post-processing affect the results. Two different class schemes were examined: one scheme with separate classes for wheel rut with and without water, and another scheme treating these as a single unified class. In addition, the effect of post-processing to eliminate overlaps between predicted masks was evaluated. The method includes annotation and preprocessing of high-resolution RGB drone images, data augmentation and a detailed training strategy with periodic validation. The model's performance was evaluated both quantitatively, using precision, recall, and F1-score, and qualitatively through visual analysis of the segmentation results. The results showed that Mask R-CNN effectively identifies wheel rut damage. Class definition had some impact on segmentation performance: treating wheel rut damage as a single unified class performed best in the mask-based evaluation, with an F1 score of 0.74 and 0.725 before and after post-processing, respectively. The pixel-based analysis showed that the class definitions yielded comparable performance: with F1 scores of 0.782 and 0.786, and overall accuracy of 0.947 and 0.948 for the unified and split class definitions, respectively. The post-processing significantly reduced overlap between predicted masks and improved visual clarity, without noticeably affecting the quantitative metrics. The study concludes that Mask R-CNN can contribute to more efficient and sustainable forest management by enabling faster and less resource-intensive identification of wheel rut damage
Fisheries Management in the Baltic Sea : Exploring the Challenges of a Sustainable Fisheries Management Through the Lens of Ecosystem-Based Fisheries Management
No full textThe Baltic Sea is currently facing increased anthropogenic pressures. Here, overfishing has been recognised to have a considerable environmental impact, affecting biodiversity, fish biomass and the sustainability of fisheries. The overexploitation of fisheries is an acute problem, and due to the continuous decline of fish stocks, it requires a sustainable management. This is especially important for the herring fisheries in the Baltic Sea, where high pressures of fishing have led some herring stocks under safe biological limits. The aim of this paper is to explore the opportunities and constraints, through the lens of ecosystem-based fisheries management, in the Swedish government's proposition “A Living Sea- increased protection, decreased eutrophication and sustainable fishing”. It is also focusing on exploring stakeholder identified challenges of implementing a sustainable management of the Baltic Herring. To answer the research questions, a document analysis and semi -structured stakeholder interviews have been performed. The results in this study identified the complexity of the fisheries management in Sweden, with a need for wider implementation of ecosystem-based fisheries management. Further, results show that there is a demand for more environmental and ecological parameters to be included in decisions regarding herring quotas at the EU level. In conclusion, it is clear that the fisheries in the Baltic Sea are facing a complex situation, in need of efficient collaborative management with clear scientific consensus.
Preventing the Invisible : A qualitative study of Trygghetens Hus's crime prevention efforts against intimate partner violence and honour-based violence and oppression
No full textAbstract Title: Preventing the Invisible - A qualitative study of Trygghetens Hus’s crime preventionefforts against intimate partner violence and honour-based violence and oppression. The aim of the study was to analyze which crime prevention methods are used within theframework of Trygghetens Hus, based on the perspectives of professionals within the policeand social services. Furthermore, the study examined potential areas for development that theprofessionals believed could enhance the effectiveness of crime prevention efforts. Toinvestigate this, semi-structured interviews were conducted with professionals from bothauthorities. The results of the thematic analysis showed that information dissemination, supportfor victims and perpetrators of violence, as well as inter-agency collaboration, were consideredthe most central crime prevention strategies. Development needs were identified in the form ofunclear routines, the need for evaluation models, and obstacles related to confidentiality, lack ofresources, and a narrow target group definition. Reaching perpetrators of violence was alsoidentified as a challenge. These aspects were considered to limit the effectiveness of theoperations and their ability to provide comprehensive support.Sammanfattning Titel: Att förebygga det osynliga - En kvalitativ studie om Trygghetens Husbrottsförebyggande insatser mot våld i nära parrelationer och hedersrelaterat våld och förtryck. Syftet med studien var att analysera vilka brottsförebyggande metoder som används inomramen för Trygghetens Hus, detta utifrån tjänstepersoner inom polisen och socialtjänstensperspektiv. Vidare undersöktes även eventuella utvecklingsområden som tjänstepersonernaansåg skulle kunna effektivisera det brottsförebyggande arbetet. För att undersöka dettagenomfördes semistrukturerade intervjuer med tjänstepersoner från båda myndigheterna.Resultatet av den tematiska analysen visade att informationsspridning, stöd till våldsutsatta ochvåldsutövare samt samverkan mellan myndigheter ansågs vara de mest centralabrottsförebyggande strategierna. Utvecklingsbehov identifierades i form av otydliga rutiner,behov av utvärderingsmodeller samt hinder relaterade till sekretess, resursbrist och en snävmålgruppsdefinition. Att nå våldsutövare identifierades också som en utmaning. Ovanståendeaspekter ansågs begränsa verksamhetens effektivitet och förmåga att erbjuda ett heltäckandestöd
Religiösa lärare i skolan – välsignelse eller problematik. : En kvalitativ studie om elevers uppfattning av religiösa religionslärare i undervisningen.
No full textThe purpose of this study has been to investigate how junior high school students perceive being taught by a religious education teacher with a religious belief, as well as how these perceptions can be interpreted based on the concepts of learning from religion. The study is based on a qualitative method where semi-structured interviews were conducted with twelve students from junior high school. The material has been analyzed using thematic approach called Jacksons interpretive approach (2009), and the theory of learning about and from religion (Grimmitt, 1981), and these has served as a framework for interpretation in this particular study. The results show that students are generally positive towards being taught by a religious teacher, as long as the teaching is conducted in a neutral and inclusive manner and also especially with a correct representation. The students emphasize that a religious religion teacher can contribute the ordinary teaching with personal experiences that make the teaching more vibrant, but they also stress the importance of balance to avoid feelings of bias and missrepresentation of any religion. Several students believe that a teacher's religious faith can deepen the understanding of religion as a lived experience rather than merely as academic material. The study provides insights into on one hand how students feels to be educated by a religious religion teacher and also does it provide new insights of how religious education can be developed in a pluralistic and democratic society where a teacher's religious background is not necessarily an obstacle – but can be a resource, provided that professional ethical principles are upheld.
(Dis)affordances and abandonment : Understanding everyday user engagement with security apps
No full textIn recent decades, numerous security technologies have emerged with the aim of fostering secure communities and providing people with the tools to bolster their everyday safety. Focusing specifically on security apps, this article explores how apps addressing security in public and semi-public spaces constitute preconditions for everyday user engagement, and vice versa, how users actively respond to these preconditions. Through identifying the (dis)affordances involved in such processes, we investigate co-production of user engagement with security apps. Drawing on observations and interviews with producers and users of apps, we explore the landscape of security apps as pervaded by processes of intended and actual (dis)affordances, sometimes also leading to abandonment of both use and users. A key finding is the divergence between the intended purposes of these apps – often framed around broad security ambitions – and their actual use, which frequently intertwines with mundane routines and logistical needs. This divergence paradoxically legitimizes broader securitisation discourses, even as the apps’ “successful use” often reflects a relatively privileged everyday life distant from tangible threats, highlighting the complex interplay between market forces, user practices, and the normalisation of surveillance
When the climate changes, what does the forest owner do? : A qualitative perspective on small-scale forest owners’ decision in a time of transition
No full textAbstract This study examines how small-scale forest owners in Sweden reason about their choice of forest management methods in relation to climate adaptation, economic conditions, and institutional structures. Through ten qualitative interviews with forest owners from different backgrounds, the study analyzes the goals, values, and obstacles that influence the decision to either continue with clear-cutting or consider alternatives such as continuous cover forestry. The results show that economics is a pervasive factor, not only in terms of profit, but also as a requirement for enabling basic forest management. At the same time, the background of the ownership, for example whether the property is inherited or purchased, influences the attitude to change. Owners with stronger emotional ties to the place tend to value traditional management methods, while newer owners are often more open to alternative methods even if they feel there is a lack of support, advice, and market access. Climate change is recognized by all respondents as a reality, but uncertainty about how to address it leads to different forms of adaptation or caution. Several respondents also point to an institutional framework in which clear-cutting is still the norm as the professional choice, which makes the transition to other methods difficult. The study contributes to existing research by providing a more nuanced understanding of small forest owners’ scope for action and complex decision-making environment. The results show a need for more flexible advisory structures, economic incentives, and political clarity to enable forestry that better balances production goals with climate and environmental ambitions. Further research should focus on institutional reforms and practical support for owners’ who want to test alternative management methods. Keywords: small-scale forest owners, clear-cutting, continuous cover forestry, climate adaptation, risk perception, forest policy, advisory services, institutional barrier
Nordic Urban Climate Policies: Analysis of the role of themes and framework enablers to work against backlash
No full text The research introduces literature about climate perceptions, policies and backlash. In this manner, the thesis explores the interrelated nature of i) how people perceive the climate crisis, ii) what form of interventions and policies respond to social pressure originating in the climate crisis, and iii) what are the backlashes to the climate policies. Subsequent to familiarization with literature, the research labels keywords and identifies patterns in the referenced materials. By mapping out patterns, the research constructs themes that support thematic analysis. Next, the paper scrutinizes the climate policies of Copenhagen, Stockholm and Oslo with thematic analysis. The analysis is helpful to understand the structure of urban climate policies that has the potential to work against climate policy backlash. As a result, the paper identifies eight themes that are put into two categories, economical and social. Themes in the economical category are: effectiveness, growth, instrument and infrastructure. The latter includes behaviour, education, fairness and participation. The integrated framework is introduced by Montfort et al. (2025). Under each category, themes are recognized: 1) Science-Policy Interface includes education and effectiveness; 2) Participation and Deliberation comprises behaviour and participation; 3) Regulatory Agency Coordination consist of infrastructure, instruments and participation; 4) Bottom-up involves fairness and growth; 5) Policy Design combines effectiveness and instruments; and 6) Communication and Framing encompasses behaviour, education and fairness. To respond to the research problem, the themes are suggested in this framework as a practical tool. While the themes’ predictive capabilities are potentially valuable for users, it lacks guidance on application. As a conclusion the research presents policy themes in a framework to enable urban climate policies that are accepted by society
Surviving Steinbeck : A Psychoanalytic and Naturalist Reading of Of Mice and Men
No full textThis essay explores John Steinbeck’s Of Mice and Men by applying Freudian psychoanalysis alongside critical perspectives on literary naturalism. By examining the novella’s portrayal of loneliness, dependency, and the collapse of the American Dream, the analysis aims to show how Steinbeck constructs a world in which emotional connection is both necessary and impossible. Drawing on Freudian concepts such as the id, ego, and superego, the essay interprets the internal conflicts and emotional bonds between characters, particularly focusing on George and Lennie. These psychological dynamics are understood not as isolated traits but as symbolic expressions of Steinbeck’s broader thematic concerns. Simultaneously, the essay draws on critical interpretations of literary naturalism to illustrate how Steinbeck depicts an environment governed by socio-economic determinism and emotional repression. At the ranch and in surrounding social contexts, moral and behavioural norms appear to take on a life of their own. However, not as expressions of a judging environment but as internalised social codes that functions as a symbolic external superego. These codes shape shape behaviour and restrict emotional expression, not because the world enforces them consciously, but because the characters have absorbed them as part of reality. This discussion is supported by selected textual examples and secondary sources in psychoanalytic and naturalist criticism. It argues that dreams, in Steinbeck’s narrative, function both as psychological defence mechanisms and as literary motifs that expose the futility of hope under naturalist conditions. Ultimately, the essay concludes that Steinbeck’s novella presents human need, particularly the need for connection, as incompatible with the deterministic world in which his characters live. By integrating Freudian theory with naturalist analysis, the essay highlights how emotional survival in Of Mice and Men is not only fragile but systematically crushed
Numerical Modeling of Electromagnetic Modes in a Planar Stratified Medium with a Graphene Interface
No full textGraphene interfaces in layered dielectrics can support unique electromagnetic modes, but analyzing these modes requires robust computational techniques. This work presents a numerical method for computing TE-polarized eigenmodes in a planar stratified dielectric slab with an infinitesimally thin graphene sheet at its interface. The governing boundary-value problem is reformulated as coupled initial-value problems and solved via a customized shooting method, enabling accurate calculation of complex propagation constants and field profiles despite the discontinuity at the graphene layer. We demonstrate that the graphene significantly alters the modal spectrum, introducing complex leaky and surface waves with attenuation due to graphene’s conductivity. Numerical results illustrate how the layers’ inhomogeneity and the graphene’s surface conductivity influence mode confinement and loss. These findings confirm the robustness of the proposed computational approach and provide insights relevant to the design and analysis of graphene-based waveguiding devices