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Multiscale integrated modeling of the Iron Oxide-Apatite Mineral System in Northern Norrbotten, Sweden
No full textThe subsurface has long supplied raw materials, yet with most giant surface-exposed deposits already discovered, exploration increasingly focuses on deeply buried mineral systems in frontier terrains. Collaborations across and beyond traditional geoscience disciplines are becoming increasingly important as deeper discoveries require multidisciplinary and integrated exploration tools. These multidisciplinary exploration tools aim to integrate the mineral system paradigm with existing geological and geophysical models and interrogate and characterize the spatial and temporal relationships of its components. This doctoral thesis employs geological modeling and integration with existing geophysical models within a multiscale framework to investigate the expression of the iron oxide-apatite mineral system in northern Norrbotten (Sweden). The region is regarded as a major metallogenic province hosting more than 40 iron oxide-apatite (IOA) deposits, including the giant Kiirunavaara deposit. More than a century of mining, exploration, and geological surveying in the area has led to an outstanding repository of geoscientific data, encompassing geological mapping, large drill core archives, and high resolution geophysical dataset, providing a solid foundation for integrated, multiscale modeling of the mineral system. At the deposit scale within the Kiruna mining district, integration of surface and drill-core structural measurements with geotechnical, structural, and lithological logging results in models that highlight how the interplay between ore-parallel and orthogonal structures controls mineralization. Low rock quality designation (RQD) values and coreorientation data systematically indicate weak rock mass at ore contacts, whereas orthogonal conjugate faults accommodated heterogeneous strain across adjacent blocks. Within the district, petrophysical measurements of major stratigraphic units establish diagnostic contrasts but also reveal pronounced intraformational variability controlled by alteration intensity and fabric development. Although stratigraphic formations can be discriminated geophysically, this heterogeneity complicates direct local-scale interpretations. The dataset provides a calibrated petrophysical reference, linking field-based geological observations and measurements with ground and airborne geophysical surveys. At the province scale, an integrated 3D model synthesizing deposit- and district-scale geological models with province- wide lithological and structural models and inversions of magnetic and gravity surveys constrain the crustal architecture of the northern Norrbotten ore province (NNOP; here defined as the area between Gällivare and Kiruna). Mafic-ultramafic intrusions occur as dense, magnetically heterogeneous domains systematically proximal to vertically extensive conductors imaged by magnetotellurics (MT), interpreted as the upper-crustal expression of transcrustal magmatic-hydrothermal conduits. IOA deposits are typically situated along second-order oblique structures that intersect or splay from major shear zones at the margin of dense and magnetic bodies, rather than within the firstorder shear zones themselves or directly coincident with MT conductors. Across deposits and prospects, diagnostic total magnetic intensity (TMI) responses, characterized by steep gradients with localized highs flanked by negative lobes constitute repeatable proximal indicators of IOA mineralization. The magmatic character of the intrusions is further constrained by petrography, whole-rock geochemistry, petrophysical characterization, and SIMS U-Pb zircon and titanite geochronology of mafic to intermediate intrusions. Two intrusive groups are distinguished, a cumulate set marked by olivine-pyroxene-plagioclase-rich assemblages, positive Eu/Eu*, elevated Sr/Yb, high density (>3.0 g/cm3) and variable magnetic susceptibilities, and another melt-proxy set of non-cumulates further subdivided into calc-alkaline and tholeiitic lineages with lower densities (2.84-3.00 g/cm3) and more uniform susceptibilities. Cumulate intrusions coincide with MT conductors, gravity highs, and concentric magnetic anomalies, supporting their interpretation as upper-crustal expressions of a deeper magmatic feeder zone. Their association with IOA deposits and complementary geochemical signatures indicates that early Svecokarelian intrusions supplied heat and likely magmatic input to the mineral system. Zircon U-Pb data place both cumulate and non-cumulate intrusions within the early Svecokarelian magmatic pulse, while titanite U-Pb results record both near-magmatic crystallization and later tectonothermal resetting events. At multiple scales, the analyses converge to show that IOA mineral systems in northern Norrbotten emerged from a dynamic interplay of magmatism, structural, and subsequent tectonothermal processes, recorded from deposit scale to province-wide crustal architecture. Embedding field-based geological observations and supporting analysis, mineral system concepts, and geophysical inversion results into integrated multiscale modeling, this thesis establishes a systematic link across scales and a coherent basis for interrogating the spatial and temporal organization of mineral system components. While the approach inevitably simplifies the complexity of a long-lived Paleoproterozoic terrain, it underscores the value of integrated geological modeling in reconciling diverse datasets into consistent frameworks. In doing so, the study refines current interpretations of IOA mineralization in northern Norrbotten and contributes to a more rigorous geological understanding of this major metallogenic province
Vacuum Membrane Distillation for Desalination: Experimental and Theoretical Investigations Using Inorganic Membranes
No full textDevelopments in the desalination technologies have been driven not only to meet the increasing demands for freshwater, but also to reduce the energy demand and cost of the process and to make desalination more sustainable. Challenges facing the desalination industry include the salinity limits of commercial processes such as reverse osmosis (RO) and brine management issues. The membrane distillation process is positioned as an emerging zero liquid discharge (ZLD) technology, yet its large-scale implementation is hindered by the low water fluxes, poor long-term stability, and high production costs of membrane materials along with the low thermal energy efficiency of the process. The aim of this thesis was to develop and assess membrane materials with high permeability, long-term stability and scalability prospects to reduce the energy and costs associated with desalination. To fulfil this aim, the integration of experimental evaluation of novel membrane materials with numerical modelling was conducted to improve understanding of factors hindering the widespread implementation of desalination technologies, including vacuum membrane distillation (VMD) and pervaporation (PV), and to gain insights for guiding future material design strategies. Ceramic membrane materials, which exhibit favorable thermal and mechanical properties for VMD applications yet are sparsely represented in the literature, were evaluated for their feasibility for large-scale deployment. Selected alumina-based membranes with different characteristic properties were evaluated and benchmarked against a commercial polymeric membrane. A silane-based grafting method was developed and implemented for the hydrophobization of the selected ceramic membranes. Among the studied membranes were asymmetric α-alumina membranes that differ in thickness, along with symmetric anodic alumina membranes that exhibited superhydrophobic characteristics. For the short-term VMD evaluation, the developed anodic alumina membranes exhibited superior permeation properties, with fluxes as high as 316 kg/(m2·h) along with NaCl rejection above 99.9%. The water flux of symmetric membranes was successfully modelled, along with model extension to describe the performance of the asymmetric membranes. These evaluations also revealed the effect of the support used in reducing the effective transport area used for flux calculations of symmetric membranes. The long-term stability of the silane-grafted membranes was assessed through500 hours of VMD operation using a feed with different NaCl concentrations at 80°C. Independent of the feed NaCl concentration, the asymmetric alumina membranes exhibited superior stability maintaining a water flux of 50 kg/(m2·h) and NaCl rejection as high as 99.9% over 500 hours of VMD operation. These membranes also exhibited superior wetting resistance in the presence of iron oxide particulate scalants. Thinner asymmetric α-alumina membranes and the symmetric membranes displayed higher water fluxes yet were prone to scaling and eventual wetting during their long-term operation. Towards enabling the wider implementation of the VMD process, novel multi-stage VMD plant layouts with integrated energy recovery were simulated using the tubular form of the asymmetric α-alumina membranes that exhibited superior long-term stability. A techno-economic analysis of the plant layouts indicated that specific thermal energy consumptions as low as 180 kWh/m3 were feasible, along with a water recovery ratio as high as 85%. For simulations based on a prospective cost for the membranes, the levelized cost of water production was within a reasonable range of 3-8 $/m3. Furthermore, it was found that choice preference between the multi-stage VMD plant layouts is influenced by the type of waste heat source available (latent versus sensible heat sources). Furthermore, the potential of PV alongside nanofiltration as candidate processes for recovering water from a thermoresponsive draw solution in a hybrid desalination process was demonstrated. The experimental evaluation together with the simulation studies indicate the high potential of the α-alumina membranes developed in this thesis
Röntgensjuksköterskor i interprofessionella traumateam : Att navigera inom professionella roller, teamdynamik och organisatoriska strukturer
No full textTrauma care is a highly complex and time-critical setting that demands rapid decision-making and synchronised interprofessional collaboration. In trauma units, teams are assembled ad hoc, bringing together multiple professionals who must work in synchrony under pressure to ensure patient safety and effective clinical outcomes. Within ad hoc trauma teams, radiographers operate under complex and time-critical conditions, providing diagnostic imaging that is critical to clinical decision-making and patient outcomes. Despite this complexity, their professional role, agency, and collaborative integration remain underexplored in trauma care research. Addressing this gap, this thesis explores how radiographers’ professional roles and positioning are shaped within interprofessional trauma teams, with particular attention to team dynamics, organisational processes, and interprofessional practice. The thesis is based on four qualitative studies: (I) a focus group study exploring radiographers’ experiences of interprofessional collaboration during trauma alerts; (II) a study using critical incident technique to examine team behaviours from radiographers’ perspectives; (III) a study combining interviews and observations to investigate interdependencies and interactions between radiographers and other team members; and (IV) a grounded theory study exploring organisational processes for collaboration, based on interviews, focus group discussions, and document analysis. Together, these studies provide a multifaceted understanding of radiographers’ roles and the dynamics of trauma team collaboration. Based on these studies, the findings demonstrate how radiographers navigate inclusion and exclusion within trauma team decision-making processes, as revealed through multiple professional perspectives, observational insights, and analysis of trauma manuals. Visibility, role clarity, and shared awareness emerge as key conditions for effective collaboration. Team behaviours and hierarchical structures shape interprofessional dynamics, with relational and cultural barriers influencing workflow and mutual understanding. Leadership is essential for recognising radiographers’ competencies and promoting ethical, inclusive collaboration. Interdependence within teams is necessary but unevenly distributed. Trust, communication, and shared goals support adaptable teamwork, while limited daily collaboration hampers relational understanding, especially between radiographers and trauma leaders. Organisational conditions, including decision-making structures, team composition, and clinical guidelines, are affected by broader structural, cultural, and relational factors, which in turn impact practical collaboration and raise implications for patient safety. The findings further suggest that radiographers’ professional positioning is continuously negotiated within organisational boundaries. Structural conditions, spatial arrangements, and situated learning practices influence how visibility, inclusion, and agency are enacted in practice. These insights underscore the need for organisational strategies that promote ethical, inclusive, and effective interprofessional collaboration in acute care settings. Recommended strategies include spatial arrangements that foster proximity and informal communication, shared platforms for knowledge exchange that support inclusive decision-making, and interprofessional education that strengthens collaboration and coordination. These strategies address key needs in the studies: clearer role definitions, enhanced visibility of radiographers’ expertise, and leadership that supports interprofessional integration within trauma teams
A Novel Explainable Artificial Intelligence Framework with Improved Learning Mechanisms
No full textArtificial Intelligence (AI) models are increasingly being deployed in various critical domains, such as healthcare, finance, law, and autonomous systems, resulting in remarkable benefits for the society. Due to black-box (sub-symbolic) nature, these AI models do not provide explanation of the predictive output. This lack of explanation results in lack of transparency between human and machine. Such opacity of black-box AI models, particularly deep learning architectures, is a significant concern. To address this concern, Explainable Artificial Intelligence (XAI) has emerged as a vital research area. The aim of XAI is to enhance transparency, trust, and accountability of AI models. Various post-hoc XAI tools explain the outputs of black-box AI models based on training datasets. However, the use of training datasets, rather than domain knowledge, makes such explanations proxy. A biased training dataset may lead to a misleading post-hoc explanation as well. In contrast, an explanation based on domain knowledge will be more trustworthy to an end user. Motivated by this, we propose a novel XAI framework, consisting of Belief Rule Based Expert System (BRBES), to predict output and explain it with reference to domain knowledge. BRBES represents domain knowledge with its rule base. It outperforms other knowledge-driven AI models to handle uncertainty due to ignorance. To improve the accuracy of BRBES, we fine-tune its parameters and structure through evolutionary learning. Moreover, to overcome the scarcity of labeled dataset in this learning mechanism, we integrate semi-supervised and self-supervised learning with BRBES. We explain the output of BRBES with respect to the most influential rule of the rule base of BRBES. Thus, the output of our proposed XAI framework becomes not only accurate, but also explainable. This doctoral thesis delves into the challenges and opportunities surrounding XAI in order to provide a comprehensive understanding of the AI output. It presents a novel XAI framework to provide domain knowledge based energy consumption prediction with improved accuracy, and explain this predictive output in non-technical human language. Then it deals with multi-modal air quality data by integrating deep learning model with BRBES. Moreover, to reduce dependence on labeled data for evolutionary learning, this thesis integrates semi-supervised and self-supervised learning with BRBES. This thesis presents six significant contributions. First, we conduct a Systematic Literature Review (SLR) on XAI using the PRISMA guidelines, delving into the numerous challenges and opportunities of XAI. Extensive research is conducted to explore the definition, terminologies, taxonomy, and application domains of XAI. It highlights various challenges of XAI, such as, no universal definition, trade-off between accuracy and explainability, and lack of standardized evaluation metrics. To address this lack of standardized evaluation metrics, we also propose a unified framework to evaluate XAI. Secondly, we present an innovative explainable BRBES (eBRBES) framework, which offers accurate prediction of building energy consumption phenomenon, while providing insightful explanation and counterfactual based on domain knowledge. As part of eBRBES framework, we also present a novel Belief Rule Based adaptive Balance Determination (BRBaBD) algorithm to assess the optimal balance of the proposed framework between explainability and accuracy. Thirdly, we propose a mathematical model to integrate BRBES with the Convolutional Neural Network (CNN). We leverage the domain knowledge of BRBES, and image data patterns discovered by CNN with this integrated approach. We predict air quality with this integrated model using outdoor ground images and numerical sensor data. Fourth, we integrate two-layer BRBES with CNN to monitor air quality using satellite images, and relevant environmental parameters, such as, cloud, relative humidity, temperature, and wind speed. The two-layer BRBES showcases the strength of BRBES in conducting reasoning across multiple layers. Fifth, we enhance the learning mechanism of BRBES by utilizing the extensive unlabeled energy data, along with limited labeled data. For this purpose, we synthetically generate unlabeled data through weak and strong augmentation. We then pseudo-label these unlabeled data by integrating semi-supervised self-training model with BRBES. By learning from both labeled and pseudo-labeled data, initial BRBES transitions to semi-supervised BRBES. Sixth, to conduct the learning mechanism of BRBES without relying on any labeled data, we integrate self-supervised learning with it. To this effect, we pseudo-label the synthetically generated unlabeled energy data with BRBES in the pretext tasks of self-supervised learning. Then, the initial BRBES learns deeper representation from these pseudo-labeled data, and transitions to self-supervised BRBES. We then transfer this BRBES, learned in a self-supervised approach, to the downstream task for performing regression of energy consumption. Based on the research findings of this thesis applied on two different phenomena, it can be argued that the proposed XAI framework provides prediction with greater precision, and explanation with higher interpretability.Funder: Stiftelsen Rönnbäret</p
Modeling and Analysis of Rotorcraft Airfoil Aerodynamics Under Martian Atmospheric Conditions
No full textThroughout history, human curiosity and the desire to explore have driven advancements in engineering capabilities and technologies. These efforts have extended our reach beyond Earth, with Mars emerging as one of the most important targets for planetary exploration. While rovers and landers have traditionally been used to study planetary surfaces, rotorcraft and other aerial vehicles have recently shown great promise for exploring the Red Planet. Such vehicles can access diverse terrains that are difficult or impossible for conventional landers and rovers to reach. However, the unique characteristics of the Martian atmosphere present significant aerodynamic challenges that must be overcome to enable sustained and efficient flight. Successful operation under these conditions requires a deep understanding of low Reynolds number aerodynamics, due to the rarefied atmosphere, and the influence of environmental factors such as pervasive Martian dust. The combination of low Reynolds number flows and suspended dust particles creates unique challenges for rotorcraft aerodynamics on Mars. This thesis investigates these challenges through Computational Fluid Dynamics (CFD) simulations, focusing on the performance of a cambered plate airfoil with 6% camber and 1% thickness, which is well suited to the Martian environment. The research addresses both fundamental aerodynamic phenomena and environmental effects, providing insights into model selection for accurate flow prediction, sensitivity of performance to Reynolds number variations, and the long-term impact of dust accumulation on airfoil behavior. This work presents a comprehensive overview of the evolution of drone designs for planetary exploration, emphasizing the main aerodynamic and control challenges involved. Operating in planetary atmospheres introduces unique difficulties, particularly due to the low chord-based Reynolds numbers and the presence of floating dust particles that can affect both aerodynamics and system reliability. The aerodynamic behavior at Reynolds numbers on the order of 104 is investigated, focusing on the effect of increasing the rotor or chord dimension. Results show that increasing the Reynolds number from 20,000 to 50,000 does not significantly improve performance, as the formation of Laminar Separation Bubbles (LSBs) on the surface still occurs. The transition model used, γ–Reθ, is able to accurately capture bubble formation. However, its limitations are also identified through comparison with other models, among which γ–Reθ is found to be the most reliable transition RANS model for these flows, since k-kL-ω fails to reproduce the correct post-stall behavior. Unsteady Navier–Stokes (UNS) simulations exhibit the same inability due to the absence of turbulence modeling; however, their lower computational cost makes them suitable for preliminary studies and acceptable for low angles of attack. The accumulation of dust particles on the airfoil surface is also examined, showing that particle deposition alters the airfoil geometry and leads to measurable changes in aerodynamic performance. While the effect is modest in the short term, it could become significant over long exposure times. The results are obtained under simplifying assumptions, such as a smooth surface and no detachment of particles. Further refinement is achieved by simulating particle deposition on an airfoil exposed solely to wind, where the wind velocity is modeled using a simple stochastic approach. The simulations account for both particle accumulation and instantaneous detachment during the run, and additional detachment is evaluated in a post-processing step. The resulting surface modification is then used to study its effect on the aerodynamic performance, providing a more complete understanding of how dust environments influence drone operation in planetary exploration. Overall, the findings contribute to a deeper understanding of low Reynolds number aerodynamics and environmental degradation mechanisms relevant to Martian rotorcraft. The results offer guidance for aerodynamic model selection, design optimization, and long-term operational strategies for future aerial exploration missions on Mars
Remaining service life estimation of existing concrete bridges through probabilistic and reliability analyses
No full textThis thesis aims to assess the remaining useful life of two representative bridge types in Sweden by combining full-scale experimental tests, Finite Element Analysis (FEA), and time-dependent reliability analysis. The combination of these methods seeks to enhance solution accuracy and reduce uncertainties. As the bridge population approaches its intended design life, concerns regarding their current condition start to rise. Recent bridge failures are proof of the need for experts to increase their efforts to accurately assess existing bridges' remaining useful life. However, structural remaining lifetime prediction is a challenging task given the complexity of structural behavior and the various environmental threats the structure faces. Additionally, inherent uncertainties are part of any engineering problem, making an exact solution difficult to achieve. Therefore, introducing probabilistic-based concepts to determine the structure capacity helps account for those uncertainties typically addressed in structural reliability analysis. Time-dependent reliability analysis offers a tool to assess the remaining useful life of a structure, expressed in terms of its time to failure. The first case study corresponds to a road existing bridge in north Sweden that has been already demolished. The structure is a prestressed box-girder concrete bridge, and it was 66 years old at the time of experimental data collection. The second case is a reinforced concrete (RC) trough railway bridge, which is a representative bridge type in Sweden. The trough bridge was cast at LTU in 2021 as a replica of the design of a decommissioned trough bridge from the Iron Ore Line. The experiments performed in both case studies are used for two main purposes: the calibration of the Finite Element (FE) models and the update of the probability distributions of the parameters involved in the time-dependent reliability analysis. This will help a better FE model to represent structural behavior and more accurate probabilistic models. Different sensors were implemented during the experimental data collection, such as fiber optic sensors (FOS), traditional strain gauges, and linear variable differential transformers (LVDTs). Given that the communication between FE and reliability analyses can be computational overwhelming, this thesis proposes an improved metamodel-based reliability algorithm which integrates the advantages of kriging, learning, and copula functions. The proposed algorithm aims to reduce the number of performance function evaluations, so the number of model runs is feasible when using FEA. The results of this research provide a practical understanding of the stochastic process for resistance deterioration in both cases. This includes degradation due to prestressing losses for the Kalix bridge and fatigue for the trough bridge. By considering the stochastic process over the years and the random nature of the loads over time, we were able to calculate the remaining useful life for the cases of no experimental information and updated using experimental data. These findings have direct implications for the maintenance and management of similar structures, providing valuable insights for the field of civil engineering and structural reliability analysis.
Hydrological processes in small stormwater infiltration facilities
No full textClimate change is expected to lead to more intense and severe rainfall events in the future and thereby significantly increase the risk of urban flooding. This change, characterized by spatial and temporal changes in precipitation patterns, challenges the capacity of existing urban drainage systems, which may be exceeded by higher runoff flows than originally anticipated. Relying solely on enlarging stormwater infrastructure to address this issue is costly and may change flood risk downstream rather than effectively resolving it. Furthermore, climate change may result in prolonged dry periods, potentially causing soil compaction and reduced infiltration capacity. In cold‑climate regions, rising temperatures are projected to increase the frequency of rain‑on‑snow events and mid‑winter snowmelt, leading to more rapid runoff and elevated risks of surface flooding. These processes can also contribute to the formation of impermeable frozen soil layers, reduce infiltration, and increase the likelihood of ice‑lens formation. Given these challenges, urban drainage systems must be both adaptable and space‑efficient, capable of managing not only increased rainfall volumes and intensities but also the hydrological effects associated with snowmelt and freeze–thaw dynamics under a changing climate. As awareness of the hydrological and environmental impacts of urbanization on catchments grows, there has been a paradigm shift towards adopting green infrastructure solutions. These approaches diverge from traditional end‑of‑pipe strategies, by emphasizing more holistic and sustainable methods. This thesis reports on a combination of modelling and field experimentation aimed at providing a better understanding of the influence of local climate (e.g., humid continental, oceanic, and subarctic climates), soil permeability (e.g., spatial and temporal variability), and initial moisture content (degree of saturation) on the water retention capacity of a grass swale and a biofilter cell. These factors were evaluated on a long‑term basis using historical meteorological time series and on an event basis, using design storms to represent a range of rainfall intensities from 1‑ to 50‑year return periods. This analysis made it possible to identify conditions that lead to the occurrence of overflow events and to test the implementation of an outflow control structure that aims to increase retention capacities of grass swales. Results showed that robust estimates of infiltration rates and a clear understanding of the local climate and its influence on soil moisture dynamics are prerequisites for designing well-functioning infiltration-based stormwater facilities. Design strategies should include a trade-off between selecting permeable soils for locations characterized by evenly distributed rainfall and prioritizing surface storage for areas with intense, short-duration events. Results from field irrigation experiments demonstrated that retrofitting an existing grass swale with a controlled outflow control release can enhance its retention capacity and reduce peak flows in downstream urban areas. Additionally, a characterization of grass swale infiltration rates revealed long-term changes in infiltration—driven by sedimentation and vegetation density. While no strong statistical correlation was found between the depth of the unsaturated zone and swale infiltration capacity, lower saturated hydraulic conductivity values were observed in shallower water table conditions. The study underscores the trade-off between selecting or modifying permeable swale soils to reduce runoff and protect groundwater quality. Finally, results from snowmelt modeling in a location with a humid continental climate showed that overflow dynamics in a biofilter cell varied significantly by the event type. Rain-on-snow events were the most frequent triggers of overflows but produced the lowest overflow volumes per event, suggesting that the snowpack buffered and delayed runoff. DRIZZL
Excavating an understanding of safety management: Experiences and perspectives from the Swedish mining industry
No full textThis thesis explores the conditions for, interpretations of and reactions to safety management strategies and practices implemented in the Swedish mining industry. The concept of ‘safety’ is depicted as one of the more important aspects of organisational management in mining industry contexts by both the mining industry itself and by researchers in related research fields. However, due to the complex nature of mining industry operations, interpretations of ‘safety’ and priorities regarding its development can vary greatly between people from different roles operating in mining workplaces. A machine operator with a more practical perspective on safety management may for example prioritise the physical safety of themselves and their colleagues and considers themselves safe when there is mutual trust and cohesion within their team. Meanwhile, managers and safety specialists with more strategic perspectives might instead focus on efforts to develop cultural values which promote safer attitudes and behaviours, and on balancing productivity with safety goals. These perspectives both seek to address important issues that safety management efforts may aim to address, yet they are characterised by different approaches to safety. While many different studies have explored safety and its management in mining contexts, the most common approach has been to consider safety based on the conceptualisations of leaders and managers. Few studies have approached safety management from the perspectives of personnel and contractor employees closer to the practical work. Fewer still are the studies that have emphasised these differences in approaches to safety in mining organisations and have examined how they can influence the outcomes of safety management efforts. The purpose of this thesis is thus to explore safety management in Swedish mining and highlight nuanced perspectives and experiences of methodologies and outcomes. In doing so, I identify how a broader understanding for and acknowledgement of the characteristics of mining industry safety management can help with addressing challenges for the continued management of safety. The empirical basis of this thesis is mainly built upon two projects conducted between 2019 and 2024 within and with the Swedish mining industry which focused on studies of safety management strategies and practices. Their contributions consisted of a total of 26 interviews with safety specialists, managers, supervisors, employees and contractor personnel from several different Swedish mining companies. In addition, these projects provided opportunities for document studies of material relating to safety management strategies and practices, and for workplace observations at some of the participating companies’ mining operations. The theoretical framework of this thesis focuses on organisational aspects which influence safety management efforts by, e.g., recommending certain approaches to management or exploring factors that can explain assumptions and behaviours relating to safety. The results show that, while safety management in the Swedish mining industry is generally perceived as having shown progress in recent years, challenges related to aspects such as communication, leadership and differing conceptualisations of safety remain. A shared characteristic of these challenges is that they relate to and involve different groups with nuanced perspectives and conceptualisations of safety. Safety management strategies may for example be difficult for employees to engage with; and physical, social and organisational separations can hinder the development of shared safety cultures between, e.g., client and contractor personnel. The experiences and examples examined in this thesis have shown how differences in expectations or interpretations can act as obstacles for effective and cohesive safety management efforts. Furthermore, this thesis has highlighted the Swedish mining industry’s normative and top-driven approaches to managing safety and safety cultures, and the challenges it faces with addressing aspects such as power relations and underlying cultural values. Ultimately, this thesis suggests that safety management efforts would benefit from seeking to understand and address the nuances between the various strategic and practical perspectives of safety involved. By encouraging communication, collaboration and mutual understanding for safety between different hierarchical levels and groups within mining organisations, these differences can be bridged and encourage more cohesive safety cultures.Denna avhandling utforskar förutsättningarna för, tolkningarna av och responsen till strategier och insatser för säkerhetsarbete som implementeras i den svenska gruvindustrins organisationer och arbetsplatser. ’Säkerhet’ som koncept skildras som en av de viktigaste aspekterna av organisatorisk styrning i gruvkontext av både gruvföretag och forskare i anknutna forskningsfält. Gruvdrift medför dock ofta komplexa organisatoriska strukturer som gör att tolkningar av ’säkerhet’ och de prioriteringar som görs gällande dess utveckling kan variera mycket mellan de olika rollerna som är aktiva på gruvarbetsplatser. En maskinoperatör med mer praktisk syn på säkerhetsarbete kanske prioriterar den fysiska hälsan av sig själv och sina kollegor, och känner sig säkrast i grupper som har utvecklat ömsesidigt förtroende och god sammanhållning. Samtidigt kan fokus för chefer och säkerhetsspecialister med mer strategiska perspektiv vara att utveckla kulturella värden inom organisationen som främjar säkrare attityder och beteenden, eller på att balansera produktiviteten med deras säkerhetsmål. Personerna i båda dessa exempel strävar efter att hantera viktiga frågor kopplade till säkerhetsarbete, men de karaktäriseras av skilda tillvägagångssätt och synsätt på säkerhet. Av dessa perspektiv är det ledares och chefers konceptualisering av säkerhet som är mest förekommande bland studier som utforskar säkerhet och system för dess utveckling inom olika gruvkontext. Få studier om gruvindustrin som utforskat säkerhetsarbete har fokuserat på anställdas och leverantörers mer praktiska tolkningar av säkerhet och synsätt på säkert arbete. Ännu färre är de studier som betonar dessa skillnader i synsätt och undersöker hur de kan påverka förutsättningarna för och resultaten av säkerhetsinsatser. Syftet med denna avhandling har därför varit att utforska den svenska gruvindustrins säkerhetsarbete för att lyfta fram nyanserade perspektiv och upplevelser av olika tillvägagångssätt och deras påföljder. På så sätt identifierar jag hur en bredare förståelse för och bekräftelse av säkerhetsarbetets kännetecknande aspekter inom gruvindustrin kan underlätta hanterandet av utmaningar för den fortsatta utvecklingen av säkerhet. Den empiriska grunden för denna avhandling byggs huvudsakligen på två projekt som utfördes mellan år 2019 och 2024 tillsammans med den svenska gruvindustrin, vars fokus var att studera strategier och insatser för säkerhetsarbete inom den industrin. Bidragen bestod av totalt 26 intervjuer med säkerhetsspecialister, chefer, arbetsledare, tjänstemän, kollektivanställda och leverantörspersonal som arbetade för flera olika svenska gruvföretag. Vidare möjliggjorde dessa projekt även för dokumentstudier av material om säkerhetsprogram och strategier, samt för arbetsplatsbesök och observationer vid några av de deltagande företagens gruvanläggningar. Det teoretiska ramverket jag nyttjade mig av för denna avhandling fokuserar på organisatoriska aspekter som har en påverkan på säkerhetsarbete och insatser för säkerhetsutveckling. Exempel inkluderar rekommendationer för ledning och styrning eller utforskande av faktorer som kan förklara antaganden och beteenden relaterade till säkerhet inom organisationer. Avhandlingens resultat visar på att många utmaningar gällande kommunikation, ledarskap och konceptualiseringar av säkerhet kvarstår för arbetet med och utvecklingen av säkerhet, trots att det upplevs ha förbättrats med tiden inom den svenska gruvindustrin. Gemensamt för dessa utmaningar är att de kan kopplas till att säkerhetsarbetet involverar olika grupper med nyanserade perspektiv av och förståelser för säkerhet. Till exempel kan strategier för säkerhetsutveckling vara svåra för anställda att involvera sig i, samtidigt som främjandet av gemensamma säkerhetskulturer mellan anställda och leverantörspersonal kan motverkas av de fysiska, sociala eller organisatoriska gränserna mellan dem. De upplevelser och exempel som studerats i denna avhandling har visat på hur skillnader i förväntningar för eller tolkningar av säkerhetsarbeten och strategier kan bidra till att förhindra utvecklingen av effektivare och mer sammanhållande säkerhetsinsatser. Vidare har avhandlingen även belyst utmaningarna för gruvindustrins normativa, ledningsstyrda säkerhetsarbete med att hantera viktiga aspekter såsom maktrelationer och latenta kulturella värderingar. I slutändan hävdar jag att den svenska gruvindustrins arbete med säkerhetsinsatser skulle gynnas av att undersöka, förstå och ta itu med nyanserna mellan de olika strategiska och praktiska perspektiven av säkerhet och säkerhetsarbete som förekommer inom fältet. Genom att främja kommunikation, samarbete samt gemensamma förhållningssätt till säkerhet mellan olika hierarkiska nivåer och grupper inom gruvorganisationer kan dessa skillnader bryggas och uppmuntra värdet av sammanhållning bland industrins säkerhetskulturer
Transparent Soils for Studying Internal Erosion
No full textEmbankment dams constitute most of Sweden’s dam infrastructure, serving hydropower production and tailings storage. Most of these structures were built more than 50 years ago, with a central core consisting of glacial tills, which is a natural material widespread availability and low hydraulic conductivity. Today, several dams have experienced problems related to internal erosion such as sinkholes or leakage, making internal erosion an essential safety issue. Suffusion is a mechanism of internal erosion that occurs in embankment dams where fines are washed out under seepage forces. The initiation of internal erosion depends on factors such as particle size distribution of the soil, hydraulic gradient and stress conditions. Broadly graded glacial tills are heterogenous material more susceptible to internal erosion by suffusion than other soils. Understanding the initiation and progression is essential for ensuring the long-term safety and performance of embankment dams. However, the initiation of this mechanism remains partially understood. Transparent soils modelling has emerged as a valuable experimental tool for geotechnical research processes that cannot be directly observed in natural soils. By matching the refractive indices of solid particles and pore fluids, transparent soils can mimic hydro-mechanical behaviors of sands and clays, enabling non-intrusive observation of deformations, seepage, and particle migration. This capability provides a unique opportunity to observe the onset of fines detachment and migration, which are critical in the initiation of suffusion, and to reproduce soil–water interactions similar to those in natural soils such as glacial tills. The thesis investigates the applicability of transparent soils for studying the initiation of suffusion. The scope of this work comprises (i) a synthesis of current knowledge on internal erosion and transparent soil technologies, (ii) the development and characterization of transparent soil mixtures with consolidation and hydraulic conductivity properties similar to various glacial till gradations, and (iii) the design of a laboratory setup for suffusion testing using these materials. The scope is limited to validating transparent soils as surrogates for glacial tills. Suffusion tests on transparent soils will be conducted in future work to fulfill the aim of this project to study the initiation of suffusion on glacial till
Driving Sustainability in Manufacturing through Digital Transformation and Collaboration
No full textAs manufacturing companies confront rising environmental, social, and economic challenges, digital transformation emerges as a vital enabler of sustainability. However, achieving meaningful impact requires more than adopting advanced technologies; it demands collaborative approaches that embed sustainability into the core of the industrial value chain. This thesis examines the so-called twin transition, defined as the integration of digital transformation and sustainability, by investigating how collaboration enables the co-creation value between manufacturing companies and technology solution providers (TSPs), which design, integrate, and deliver technology solutions, as well as among TSPs themselves, thereby contributing to sustainable production. The research demonstrates how digital technologies can drive sustainability through collaborative efforts between manufacturers and TSPs. Building on theoretical insights and empirical findings, it conceptualises a value constellation in which manufacturers and TSPs collaborate to provide tailormade technology solutions that foster sustainability. This approach shifts the focus from fragmented or isolated initiatives toward a collaborative value constellation, where digital technologies are applied to improve operational performance and contribute to environmental and social outcomes. Furthermore, the thesis synthesises theoretical and empirical insights to support the twin transition, with a particular focus on how manufacturers and TSPs can collaborate and leverage digital technologies to drive sustainability. The contributions of this thesis rest on three interrelated pillars: (1) embedding value co-creation as an approach across interconnected actors to drive sustainability, (2) demonstrating how inter-organisational collaboration can align digital and sustainability agendas, and (3) leveraging strategic use of digital transformation to foster sustainability into both technological and non-technological innovation processes. By synthesising theoretical and empirical insights, this research makes contributions to the fields of innovation management, digital transformation, sustainability, and collaboration studies