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ISSUES: Information security and digital services for sustainable designs : Report 2023-2025
No full textCognitive Neuroscience in Alpine Skiing: Introducing Computational Sports Medicine for Performance Optimization
No full textWhile sport psychology has long emphasized mental and cognitive aspects of performance, sports medicine has traditionally focused on musculoskeletal and physiological aspects, largely overlooking the brain's central role in athletic performance. This narrative review aims to bridge this gap by introducing Computational Sports Medicine, a novel framework that integrates cognitive neuroscience with established physiological and biomechanical measures. Using alpine skiing as a primary example, this review examines the critical role of working memory updating in dynamic environments, discusses how neural processes enable adaptation, and proposes Computational Sports Medicine as a unifying predictive framework. This approach moves beyond descriptive analysis to provide objective, quantifiable metrics, testable models, and the ability to simulate “what-if” scenarios for proactive intervention. Practical implications for training include developing sport-specific cognitive tasks, individualizing variability in motor and cognitive learning, and leveraging technologies like virtual reality and wearable sensors. The review primarily targets elite and sub-elite athletes, for whom cognitive and environmental demands are most pronounced. This brain-inclusive framework offers a personalized approach to performance optimization, injury prevention, and safe return-to-play decisions, positioning the brain as the central organ to the future of sports medicine.Full text license: CC BY</p
Optical Frequency Comb Generation and Injection Locking for Photonic Receiver Applications
No full textHeterodyne down-conversion of radio frequencies from an optical carrier can be achieved by mixing the carrier with a frequency offset copy of itself. A stable yet tunable frequency offset allows for wideband down-conversion and is of interest for photonic receiver applications. This thesis investigates a method for creating a stable carrier copy by means of optical injection locking with a secondary semiconductor laser. A setup is used where the carrier field is generated by a laser and is broaden into an optical frequency comb by electro-optic modulation before being injected into the second laser. Depending on the frequency offset and power difference between the lasers, one comb line can be amplified, creating a copy of the carrier at a fixed frequency offset. Optical injection locking is found to successfully amplify only one comb line while suppressing the remaining comb below the noise floor of the detector, resulting in a sideband suppression ratio over 43 dB. The frequency offset stability between the lasers is found to be limiting for the suppression since the low injection ratio needed for near or below the noise floor suppression is accompanied by a narrow locking width
Experimental study on the permeability characteristics of reconsolidated salt: Effects of gas and confining pressure
No full textReconsolidated salt, formed from crushed halite under compaction, is a promising buffer and sealing material for deep geological repositories of high-level radioactive waste (HLW) because of its low permeability and self-healing properties. This study investigated the gas permeability behavior of reconsolidated salt with varying porosities under different confining pressures and inlet gas pressures using nitrogen gas. Based on nuclear magnetic resonance (NMR) technology, the pore structure of reconsolidated salt specimens with different porosities was tested and imaged. The experimental results demonstrate that gas permeability decreases with increasing gas and confining pressures, with gas pressure having a more pronounced effect. The observed permeability‒pressure relationship is attributed primarily to the Klinkenberg effect, with gas slippage along pore walls enhancing the measured permeability under low-pressure conditions. Using the Klinkenberg correction, the absolute permeability values of reconsolidated salt were derived, reaching as low as 10−19 m2 in low-porosity samples. These values are significantly lower than the apparent gas permeability, indicating excellent sealing performance comparable to or superior to that of bentonite. A logarithmic relationship between the absolute permeability and confining pressure was established, providing a quantitative basis for permeability prediction under repository stress conditions. NMR imaging results indicate that with decreasing porosity, the connectivity between pores also gradually diminishes. Additionally, the slip factor was found to increase with increasing confining pressure, underscoring the evolving influence of pore geometry on gas transport mechanisms. Permeability of reconsolidated granular salt decreases with porosity following a power-law relationship, and the healing supports its sealing effectiveness. This study provides essential data and theoretical insights for evaluating the long-term sealing performance of reconsolidated salt in salt-based HLW repositories.Full text license: CC BY 4.0;Funder: Rut and Sten Brand foundation; Chongqing Youth Innovative Talent Project (CSTB2024NSCQ-QCXMX0011); National Natural Science Fund of China (No. 52274073); National Key R&D Program of China (2024YFB4007100); China Postdoctoral Science Foundation (2023M730427); Chongqing Postdoctoral Research Project (2023CQBSHTB3139); Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering Safety (SKLGGES-024006) </p
Experiences of cancer care among people living in rural areas : A qualitative literature study
No full textCancer är vanligt och personer bosatta i glesbygd har ofta begränsad tillgång till specialiserad sjukvård i närområdet. Av denna anledning behöver många personer bosatta i glesbygd resa långa avstånd för att få tillgång till cancervård som vanligtvis är lokaliserad till större sjukhus. Syftet med denna litteraturstudie var att beskriva hur personer bosatta i glesbygd upplever cancervård. Studien genomfördes som en litteraturstudie med ett inifrånperspektiv, där tretton kvalitativa artiklar analyserades genom kvalitativ innehållsanalys. Resultatet visade att personer i glesbygd upplevde oro över vårdens kvalitet och tillgänglighet samt att långa resor i samband med behandling var tidskrävande och påfrestande för vardagen. Vidare framkom att kostnader kopplade till behandling och resor skapade stress. En känsla av ensamhet och isolering kunde uppstå och betydelsen av vård nära hemmet och familjen var framträdande. Det framkom även att det fanns behov av socialt och praktiskt stöd för personerna. Slutsatserna är att personer som bor i glesbygd möter särskilda utmaningar som sträcker sig bortom själva cancerdiagnosen. För att kunna tillgodose dessa personers behov krävs en ökad förståelse för den komplexa livssituationen som uppstår när behandling innebär att under perioder vistas långt från hem och närstående.
Promoting a Sustainable Digital Work Life for People with Cognitive Difficulties
No full textThe digitalization has changed the work life and created new cognitive demands that can be challenging to manage in digital work and everyday life for people with cognitive difficulties related to neurological disorders. Nevertheless, the consequences of these changes are largely unexplored. Thus, the overall aim of this thesis is to enhance knowledge of how people with cognitive difficulties experience digital work and other occupations in everyday life, and how to promote a sustainable digital work life. The thesis comprises four qualitative studies. Study I explored and described how people with cognitive difficulties engaged in digital work, experienced their vocational situation and how it influenced their everyday life. This study was designed as a qualitative, descriptive, multiple case study. Data were collected through semi-structured interviews, self-reports and assessments from seven participants with neurological disorders and analysed using pattern matching. The findings suggest that performing digital work was cognitively demanding and influenced engagement in other valuable occupations. Work-related obligations were prioritized over other occupations in everyday life. Additionally, digital work was facilitated by support from employers and family, as well as by using self-initiated management strategies in challenging situations. Study II described how people with cognitive difficulties due to neurological disorders experienced their use of self-initiated strategies to manage digitalized work and other occupations in everyday life. Eleven participants participated in qualitative interviews, supported by a dialogue support tool. The findings of the qualitative content analysis imply that self-initiated management strategies were often crucial for managing challenging situations in digital work and to uphold engagement in occupations outside work. Having an ability to self-evaluate and reflect upon the use of strategies was necessary for a conscious, flexible and effective use. Study III described employer representatives’ experiences of work environment management focusing on employees with cognitive difficulties working in a digital environment. Focus group discussions with six employer representatives were utilised for data collection. The focus group analysis indicated that aligning the work abilities of employees with cognitive difficulties to the evolving cognitive demands of digital work, was a continuous process. Given the dynamic nature of both employee’s abilities and work demands, fostering a trustful relationship and collaboration with the employee was crucial. This ongoing process required knowledge of digital technologies, the impact of cognitive difficulties on work ability and support from and collaboration with other professionals with related expertise. Study IV, explored and described how an internet-based occupational therapy intervention can support self-management in people with cognitive difficulties performing digital work and other occupations in everyday life. The study was designed as a qualitative, descriptive, case study. Data were collected at three occasions from four people with neurological disorders participating in the intervention ”Strategies for Empowering activities in Everyday life” [SEE 2.0.]. Data gathered through semi-structured interviews, self-reports and assessments were analysed using pattern matching. The findings suggest that SEE 2.0 has the potential to support the development of self-management and initiate a process of change in people with cognitive difficulties, thus having the possibility to facilitate a sustainable digital work and everyday life. The enhanced understanding derived from this thesis can be used to develop vocational rehabilitation for people with cognitive difficulties in digital work. Taking a wider approach when evaluating and identifying cognitive difficulties and considering work and other occupations as an entirety rather than separate parts, is vital. This to facilitate sustained engagement in digital work and a balanced everyday life. It is also essential to have continuous supportive collaboration between employees and employers, as abilities and demands are in constant interaction and change in digital work. Finally, the thesis emphasizes the importance of utilising each person's own resources and strategies to empower self-management, to promote a sustainable digital work life
Micro Transactions and Automation of Industrial Assembly Planning
No full textThis thesis discusses two subjects: distributed ledgers scalable enough to support micro-transactions, and automating assembly planning in manufacturing industries. Established blockchain solutions achieve high robustness and reliability. By being distributed and decentralized, they avoid a single point of failure, and fault-tolerant consensus mechanisms ensure that the system works as intended in the presence of malicious participants. However, their main weakness is scalability. The two most popular and well-known blockchain solutions require all nodes to store all transactions, and the transaction throughput is far too low to compete with traditional, centralized transaction processing systems. To improve scalability, systems have been developed that split the network nodes into groups that can process transactions in parallel, also known as sharding. We propose a novel approach to sharding, called ScaleGraph, which uses concepts from distributed hash tables to define shards dynamically. Nodes store and validate only transactions involving those accounts that are close to the node according to a logical distance metric. This greatly reduces the storage burden on each node and allows any number of transactions involving distinct accounts to be validated in parallel. By employing a synchronous consensus protocol, shards can be kept smaller without sacrificing fault tolerance, especially in a permissioned environment where participation can be controlled and a small fraction of malicious nodes can be assumed. Manufacturing is a highly complex process in many industries, involving many different planning problems, and increasing automation has the potential to make manufacturing more efficient. This thesis presents a proof-of-concept solution to the kitting layout planning problem, where a list of parts has to be placed on a kitting wagon for delivery to an assembly line station. However, some problems have proven difficult to automate in practice, despite decades of research. One such problem, assembly line balancing, is analyzed in depth. We identify fundamental challenges that make the goal of complete automation implausible in some industries, such as automotive manufacturing. Human intervention is thus unavoidable, suggesting that assisted planning is a more promising approach for achieving increased automation in practice. Therefore, we make the case that bridging the gap between theory and practice requires decision-support systems that enable an iterative and interactive workflow
Modelling Dynamic Flow Conditions for Fish Habitats in Regulated Rivers
No full textHydropower is an important renewable energy source providing flexible operating conditions that balances the increasing intermittent energy from wind- and solar power. Hydropower however, comes with other environmental challenges by altering the ecological conditions in the rivers by presenting flow conditions such as hydropeaking. To fulfill the Swedish Environmental Code and the demand from the European Water Framework directive to achieve good ecological status (GES) for all watercourses, measures to improve the ecology in the river for each hydropower plant must be presented. Investigating potential restoration measures might be both costly and time-consuming as they are often specific to the site and species involved. Hydraulic modelling of flow conditions connected with individual-based models (IBMs) to evaluate fish population growth, and behaviour, is one way to make these estimations more cost- and time-efficient. The aim of this thesis is to investigate how the results of hydraulic models can be used with IBM’s and how different assumptions in the modelling process could create deviations that could further propagate into the IBM’s. A 2D hydraulic model over a regulated river in northern Sweden is presented where the restoration focus is improving European grayling habitat. As a first step, paper A investigates how modelling parameters could influence the hydrodynamics in the river, and in turn impact the habitat estimations. The results shows that the Neumann boundary conditions are more sensitive to Manning roughness than fixed water level boundaries, especially near upstream and downstream enclosure areas. A fixed water level boundary with velocity measurements at the inlet and outlet can minimize boundary effects on roughness calibration. Careful selection of roughness distribution areas, particularly in high-velocity zones, is crucial as it impacts bed shear stress, and velocities, which can be used for estimating feasible habitat. A gradual roughness transition between calibration areas may improve model accuracy. In a second step, paper B compares a steady-state interpolation method with transient simulations since the IBM implements steady-state simulations of different constant flows to interpolate the depth and velocities across the river for different discharge hydrographs. The goal was to assess how the limitations of a steady-state approach impact different parameters in the IBM’s and how this could affect the long-term habitat. Steady-state and transient simulations were compared, focusing on WSE, spawning habitat and bed shear stress. Steady-state models failed to capture temporal dynamics caused by neglect of time displacement and damping by assuming uniform response times across the river. The bed shear stress was under-predicted by the steady-state interpolation which could lead to inaccurate estimations of suitable spawning grounds and also, the risk of redd scouring. Uncertainties in the depths and velocities over time from the hydraulic model could propagate further in the IBM’s causing the long-term evaluation of fish population to be inaccurate especially when the flow conditions are highly varying during the years where a transient model is preferred. Finally, paper C investigates how the dynamic flow conditions effect the bed shear stress. When no substrate data over the riverbed is available, the bed shear stress can serve as a substitute for identifying suitable spawning areas as input for the IBM. The paper presents the hydraulic conditions in the river during a period of 2 months between May and July to capture the spring flood together with some hydropeaking events during summer. The spawning grounds considering depths and velocities were presented with the maximum bed shear stress during the time period to identify and evaluate possible restoration areas. To evaluate the stability of different spawning gravels used for restoration, the Wilcock-Crowe bedload transport model was implemented in the model. The erosion and sedimentation of the added spawning gravel followed the maximum bed shear stress curves. The results can be used further to evaluate different restoration measures together with the fish population growth with IBM
Finite Element-Based Investigation of Rotor-Bearing-Stator Dynamics
No full textRotating machinery forms the backbone of modern energy conversion, facilitating the transfer of energy between a fluid and a rotating component, the rotor. Mathematical modeling of rotating machinery has become increasingly sophisticated due to growing demands in modern machine design, primarily driven by the increase of angular momentum sustained by the rotor. Thus, the study of rotating machine dynamics has evolved to improve prediction accuracy and ensure operational stability. A rotor typically consists of shafts, disks, and blades, supported by bearings that enable rotation relative to a stationary structure. Bearings are tasked to provide both support and energy dissipation. While rotor-bearing models often suffice for dynamic analysis of rotating machinery, stators—such as casings, housings, and foundations—can influence dynamics through rotor-stator interactions. For example, compliant bearing supports may impair bearing function, while generator stators exert significant electromagnetic forces that impact operational stability. The integrated model of these components is known as a rotor-bearing-stator (RBS) system. While traditional rotor dynamic analysis typically utilizes shaft elements to model the rotor assembly and reduces the stator and bearing to discrete spring elements, a full three-dimensional representation overcomes the kinematic and geometric restrictions of beam theory, enabling the analysis of vastly more complex systems. Furthermore, the increased degrees of freedom lead to greater computational complexity, particularly noticeable for vertical machinery. Unlike horizontal rotors, vertical systems inherently experience large dynamic displacements and lack a stationary point of operation, necessitating the use of nonlinear bearing formulations. Hydropower machinery is generally supported by hydrodynamic journal bearings. This requires tracking the rotor position at each time step and solving equations for fluid-film interaction, further increasing computational demands. This compilation thesis investigates the dynamics of integrated hydropower systems, with emphasis on how to accurately and efficiently model complex, vertical systems by finite element methods. The thesis constitutes three applied studies of vertical RBS-systems, mostly related to hydropower applications. The first paper focuses on a three-dimensional model of a floating-rim synchronous generator, with emphasis on deformation under electromagnetic and centrifugal loads. The second paper explores the interaction between tilting pad journal bearings and an elastic support frame, exploring the potential implementation of nonlinear journal bearing formulations within a three-dimensional finite element framework. Finally, the third paper investigates the impact of a compliant generator-bearing support on the stability of a hydropower rotor-bearing system
Promoting construction innovation : A public infrastructure client’s adaptation of procurement and project management strategies
No full textThe construction and infrastructure sector is a significant contributor to global carbon emissions, necessitating substantial changes to support, what can be called, the sustainability transition. Public infrastructure clients are expected to lead this transition by promoting construction innovation, while engineering consultants, involved in the planning and design of projects, play a key role in supporting these efforts. Public procurement is widely recognized – politically – as a key strategic tool for promoting innovation and advancing sustainability, despite the project-based sector the role of project management remains largely overlooked. However, previous research highlights the importance of both procurement and project management strategies in promoting construction innovation. To effectively promote innovation, these strategies must be adapted to the specific characteristics of each project and should emphasize flexibility and involvement of actors. Despite the procurement and project management strategies’ acknowledged significance, they are often treated as separate governance mechanisms within previous research, failing to account for their interconnected nature. The purpose of this thesis is to increase the understanding of how a public infrastructure client promotes innovation towards the sustainability transition through adaptation of procurement and project management strategies in planning and design of new infrastructure. A longitudinal single-case study of the largest public infrastructure client in Sweden, the Swedish Transport Administration (Trafikverket), provides empirical insights. The findings show that despite high expectations for public clients to promote innovation – especially in designated pilot projects – these projects are evaluated and managed through conventional linear processes, short-term goals, and paradigms. While innovation is acknowledged as a multidimensional concept requiring flexibility and collaboration, procurement and project management strategies remain predominantly control-oriented, emphasizing efficiency, problem-solving, and monitoring. This approach is found to limit the perceived promotion and impact of construction innovation in practice. By problematizing the concept of comprehensive governance – integrating procurement and project management – this thesis highlights how public clients’ reliance on detailed process control and the aligning with a hard paradigm, which is not well-suited to promote construction innovation. The research underscores the interdependence of procurement and project management strategies, advocating for a holistic governance perspective in construction management research and practice. Addressing this interconnection, both within research and practice, is crucial for developing strategies that effectively promotes construction innovation supporting the sustainability transition in public infrastructure projects