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  • Grafström, Jonas
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Samhällsvetenskap. Ratio, Sweden.
    Decoding the barriers for a circular plastics industry: An equation framework2025Inngår i: Sustainable Production and Consumption, ISSN 2352-5509, Vol. 54, s. 375-388Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Empirical research on barriers to a circular plastics economy has predominantly relied on case study approaches. While research has provided insights into the conceptual and anecdotal aspects of these barriers, a gap remains in the application of formalized methodologies to systematically understand and address them. This paper seeks to bridge this gap by developing an equation system tailored to the plastics industry, bringing clarity to the complex interplay of factors that constitute barriers to a circular economy. The study identifies four primary barriers to the circular economy, as documented in the literature between 2017 and 2024: economic, institutional and regulatory, technological, and social. The results include 24 equations, synthesized into four master equations. A mathematical case study demonstrates how numerical weights, and the relative importance of variables can differ between countries, offering a practical guide for applying the framework across diverse contexts. The study concludes that reducing regulatory ambiguity, scaling recycling infrastructure, and fostering consumer trust in recycled materials are critical steps. However, each country will face unique challenges, requiring policymakers to adopt tailored approaches and variable weighting.

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  • Lin, Janet
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik. Division of Product Realization, Mälardalen University, 63220 Eskilstuna, Sweden.
    Silfvenius, Christofer
    Scania Technical Center, Scania AB, 15132 Södertälje, Sweden.
    Some Critical Thinking on Electric Vehicle Battery Reliability: From Enhancement to Optimization2025Inngår i: Batteries, E-ISSN 2313-0105, Vol. 11, nr 2, artikkel-id 48Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Electric vehicle (EV) batteries play a crucial role in sustainable transportation, with reliability being pivotal to their performance, longevity, and environmental impact. This study explores battery reliability from micro (individual user), meso (industry), and macro (societal) perspectives, emphasizing interconnected factors and challenges across the lifecycle. A novel lifecycle framework is proposed, introducing the concept of “Zero-Life” reliability to expand traditional evaluation methods. By integrating the reliability ecosystem with a dynamic system approach, this research offers comprehensive insights into the optimization of EV battery systems. Furthermore, an expansive Social–Industrial Large Knowledge Model (S-ILKM) is presented, bridging micro- and macro-level insights to enhance reliability across lifecycle stages. The findings provide a systematic pathway to advance EV battery reliability, aligning with global sustainability objectives and fostering innovation in sustainable mobility.

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  • Yu, Jun
    et al.
    State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China; Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design, MIIT China, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China.
    Wang, Linzeng
    State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China; Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design, MIIT China, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China.
    Kang, Guoqiang
    State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China; Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design, MIIT China, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China.
    Lin, Xin
    State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China; Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design, MIIT China, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China.
    Tian, Lijun
    State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China; Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design, MIIT China, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China.
    Guo, Pengfei
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Produkt- och produktionsutveckling.
    Wu, Liangyi
    State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China; Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design, MIIT China, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China.
    Huang, Weidong
    State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China; Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design, MIIT China, Northwestern Polytechnical University, Xi’ an, 710072, People's Republic of China.
    Effects of electrolytes on electrochemical behaviour and performance of Ti6Al4V alloy prepared by laser directed energy deposition2025Inngår i: Journal of Materials Research and Technology, ISSN 2238-7854, E-ISSN 2214-0697, Vol. 35, s. 1913-1925Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study investigates the influence of electrolytes on the electrochemical (EC) performance of Ti6Al4V alloy fabricated via laser directed energy deposition (LDED). The EC dissolution efficiencies and surface roughnesses of the alloy are assessed, and the surface passivation films are analyzed through impedances, vacancy concentrations, compositions, and nanostructures. The results demonstrate that the NaCl + EDTA-2Na electrolyte attains a moderate EC machining efficiency and the optimal surface roughness of 0.31 μm at its best performance. Transmission electron microscopy reveals distinct dissolution variations between the α and β phases during ECM. The average film thickness on the α-phase is approximately 400 nm in NaCl + NaNO3 electrolyte, 35 nm in NaCl + EDTA-2Na electrolyte, and merely 10 nm in NaCl + NaBr electrolyte. Furthermore, the anionic effects on transpassive dissolution in different electrolytes are illustrated based on the point defect model. These findings reveal that, when compared to the NaCl + NaBr electrolyte, the average ECM efficiency in NaCl + EDTA-2Na drops by 4.3%, whereas the surface roughness experiences a significant reduction of 76.3%. Especially, the dissolution difference between α and β phases can be suppressed in NaCl + EDTA-2Na electrolyte. These insights can guide the selection of electrolytes for efficient and precise ECM of LDED-prepared dual-phase titanium alloy in industrial applications.

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  • Löfgren, Robin
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Sopiha, Kostiantyn V.
    Division of Solar Cell Technology, Department of Materials Science and Engineering, Uppsala University, Uppsala 75237 Sweden.
    Öberg, Sven
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Larsson, J. Andreas
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Neutral supercells for charged impurities by explicit acceptor/donor compensation − Defects in diamond2025Inngår i: Computational materials science, ISSN 0927-0256, E-ISSN 1879-0801, Vol. 250, artikkel-id 113685Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    When investigating charged defects in semiconductors or insulators, the traditional method to render them charged is by adding/removing electrons to/from the supercell. However, this method can be problematic due to the necessity to include an artificial jellium counter-charge. Herein, we investigate an alternative approach to charging – using explicit compensating donors/acceptors, in the form of substitutional atoms with suitable valence. This method yields pairs of charged defects in neutral supercells, thereby eliminating the need for jellium altogether. We test the method for a collection of model systems consisting of charge-compensated point defects in diamond (NV/SiV-centers, substitutional nitrogen/phosphorous/oxygen/sulfur donors, and substitutional boron/beryllium acceptors). We report the resulting charges, local geometries, spin densities, Kohn-Sham energy levels, and electronic transition energies for selected defect pairs and compare them with those for the individual defects in charged supercells. We find that charging by explicit donors/acceptors works well if properly designed but interpretation of the results can be challenging. We advocate for the cautious use of this approach to complement traditional charge correction schemes and to analyze the charge-compensation mechanisms occurring in actuality.

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  • Nilsson, Robert
    et al.
    Section of Sports Medicine, Department of Community Medicine and Rehabilitation, Umeå School of Sport Sciences, Umeå University, Umeå, Sweden.
    Theos, Apostolos
    Section of Sports Medicine, Department of Community Medicine and Rehabilitation, Umeå School of Sport Sciences, Umeå University, Umeå, Sweden.
    Lindberg, Ann-Sofie
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik, Hälsa, medicin och rehabilitering.
    Malm, Christer
    Section of Sports Medicine, Department of Community Medicine and Rehabilitation, Umeå School of Sport Sciences, Umeå University, Umeå, Sweden.
    Predicting competitive alpine skiing performance by multivariable statistics—the need for individual profiling2024Inngår i: Frontiers in Sports and Active Living, E-ISSN 2624-9367, Vol. 6, artikkel-id 1505482Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Introduction: Predicting competitive alpine skiing performance using conventional statistical methods has proven challenging. Many studies assessing the relationship between physiological performance and skiing outcomes have employed statistical methods of questionable validity. Furthermore, the reliance on Fédération Internationale de Ski (FIS) points as a performance outcome variable presents additional limitations due to its potential unreliability in reflecting short-term, sport-specific performance. These factors complicate the selection of appropriate tests and the accurate prediction of competitive outcomes.

    Method: This study aimed to evaluate the predictive power of a generalized physiological test battery for alpine skiing performance, as measured by FIS points, utilizing multivariable data analysis (MVDA). Physiological test results from a total of twelve (n = 12) world-class female skiers were included in the analysis.

    Results: The result on goodness of regression (R2) and goodness of prediction (Q2) in this study indicate that valid Orthogonal Projection to Latent Structures (OPLS) models for both Slalom and Giant Slalom can be generated (R2 = 0.39 to 0.40, Q2 = 0.21 to 0.15), but also that competition performance still cannot be predicted at a group level (low Q2). In contrast, higher predictive power of competitive performance was achieved on an individual level using the same data (R2 = 0.88 to 0.99 and Q2 = 0.64 to 0.96).

    Discussion: The findings of this investigation indicate that the selected tests employed in this study exhibit limited generalizability for the assessment of elite alpine skiers, as the predictive value of specific physiological parameters on competitive performance appears to be highly athlete-dependent.

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  • Zeng, Changfeng
    et al.
    College of Mechanical and Power Engineering, Nanjing Tech University, Nanjing 211800, China.
    Zhao, Hongwei
    State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 211800, China.
    Zhang, Lixiong
    State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 211800, China.
    Yu, Liang
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Continuous and rapid preparation of urea-formaldehyde resin microspheres with adjustable sizes and structures in a microchannel reactor2025Inngår i: Chemical Engineering and Processing, ISSN 0255-2701, E-ISSN 1873-3204, Vol. 209, artikkel-id 110184Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Urea-formaldehyde (UF) resin microspheres prepared by polymerization of urea and formaldehyde have broad applications because of their unique properties. In this paper, we present the preparation of UF microspheres with particle sizes of several microns at 100–180 °C and 1.5 MPa in 6–24 s in a simple microchannel reactor. A urea aqueous solution and formaldehyde solution containing formic acid as the catalyst were used as raw materials. Porous and flower-like UF microspheres as well as dense ones can be readily produced, with the former obtained mainly at lower temperatures, shorter residence times, and lower reactant concentrations. The porous microspheres can further grow to dense ones by prolonging the residence time, increasing the reaction temperature, or using reactants with higher concentrations. Compared with the present mainly used batch process to prepare UF microspheres using the same raw materials which need 3 h at 50 °C, this preparation method is swift and versatile in adjusting the particle size and structure. Moreover, flower-like UF microspheres could be produced and the pore size could be adjusted without additives. The results indicate a more environmentally friendly and economical synthesis method we developed. A possible formation mechanism of UF microspheres with various structures was proposed.

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  • Hossain, SK Saddam
    et al.
    Akhtar, Farid
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Development of lightweight architecture of geopolymer via extrusion-based 3D printing for CO2 capture2025Inngår i: Journal of the European Ceramic Society, ISSN 0955-2219, E-ISSN 1873-619X, Vol. 45, nr 7, artikkel-id 117191Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mitigation of CO2 emissions has been a major societal concern in recent decades, and post-combustion capture of CO2 is an effective strategy proposed by the research community. Hierarchical porous geopolymer monoliths were fabricated using extrusion-based 3D printing for CO2 capture. The kaolin-based viscoelastic paste was first formulated using alkali activators and plasticizer, and it was observed that the viscosity increased over time. Second, the 3D printed porous monoliths were treated using different post-processing conditions like thermal curing, hydrothermal curing, and high-temperature thermal treatment and their physico-mechanical properties and CO2 adsorptive were investigated. Thermally cured and heated specimens exhibited an amorphous phase, while zeolite phases were observed in the hydrothermally treated specimens. Printed and subsequently hydrothermally treated mechanically stable specimens showed significantly higher CO2 adsorption (1.22 mmol/g) than conventionally casted geopolymer (0.66 mmol/g). Combining 3D printing with geopolymer technology could offer a sustainable approach design and structure adsorbents for CO2 capture.

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  • Zuo, Zhida
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap. State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China.
    Lu, Xiaohua
    State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China; Suzhou Laboratory, Suzhou 215125, P. R. China.
    Ji, Xiaoyan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Modeling the Viscosity of Ionic Liquids and Their Mixtures Using ePC-SAFT and Free Volume Theory with an Ion-Based Approach2025Inngår i: Industrial & Engineering Chemistry Research, ISSN 0888-5885, E-ISSN 1520-5045, Vol. 64, nr 4, s. 2446-2464Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this work, we developed the electrolyte perturbed-chain statistical associating fluids theory (ePC-SAFT) coupled with free volume theory (FVT) using an ion-based approach (i.e., treating IL cation and anion as distinct species) to model the viscosities of 72 ionic liquids (ILs) across various temperatures and pressures. To evaluate the model performance, we compared the ePC-SAFT-FVT model employing a molecular-based approach (i.e., treating IL as a single pure substance) developed in our previous work. The results indicate that the ion-based approach demonstrates desirable performance, achieving an average ARD of 8.73%. This is comparable to the molecular-based approach, which has an average ARD of 6.09%. Importantly, the ion-based approach requires fewer adjustable parameters, reducing the number from 216 to 81 for 72 ILs, and offers enhanced flexibility by allowing the combination of both cation and anion parameters for predictions. Additionally, the ion-specific ePC-SAFT-FVT model was employed to predict the viscosities of IL mixtures, which were then compared to experimental data of 19 IL mixtures. The findings reveal that the model effectively predicts the viscosity of most IL mixtures, achieving an average ARD of 9.1%. Furthermore, the ion-based approach demonstrates superior predictive performance compared to the molecule-specific ePC-SAFT-FVT model. This study indicates that the ePC-SAFT-FVT model, using an ion-based approach, reliably represents the viscosity of pure ILs and IL mixtures, leveraging the flexibility of cation and anion parameter combinations to enhance predictive capabilities.

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  • Piya, A. K.
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Maskinelement. School of Mechanical Engineering, University of Leeds, Leeds LS2 9JT, UK.
    Yang, L.
    School of Mechanical Engineering, University of Leeds, Leeds LS2 9JT, UK.
    Emami, N.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Maskinelement.
    Morina, A.
    School of Mechanical Engineering, University of Leeds, Leeds LS2 9JT, UK.
    Effect of Nanodiamonds on Friction Reduction Performance in Presence of Organic and Inorganic Friction Modifiers2025Inngår i: Lubricants, E-ISSN 2075-4442, Vol. 13, nr 1, artikkel-id 1Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The strive to reduce harmful emissions from transport has resulted in an increased emphasis on minimising friction in lubricated contacting components to improve the energy efficiency of automotive engines. In this sense, it is of particular interest to investigate whether a synergistic tribological performance could be achieved by combining two or more friction modifier additives with nanoparticles. This study conducts a comprehensive investigation into the tribological characteristics of lubricant formulations enriched with nanodiamonds (NDs), combined with organic (Glycerol Monooleate, GMO) and inorganic (molybdenum dithiocarbamate, MoDTC) friction modifiers and a low-concentration anti-wear additive (Zinc dialkyl dithio-phosphate, ZDDP). The interaction between NDs and MoDTC has been evaluated using reciprocal sliding tests at two different temperatures. The outcomes of the tribological experiments revealed that the interaction of NDs and MoDTC can enhance the friction and wear performance of steel pairs. However, this enhanced performance is shown to highly depend on other additives present in the lubricant mixture. Analysis of wear scars using High-Resolution Transmission Electron Microscopy (HRTEM), Atomic Force Microscopy (AFM) and Raman spectroscopy reveals that when NDs are fully entrapped into the formed tribofilm that contains the MoDTC-derived MoS2 layer, the lowest friction coefficient can be achieved.

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  • Siame, Moses Charles
    et al.
    School of Engineering, University of Zambia, Great East Road, Lusaka 32379, Zambia.
    Zvarivadza, Tawanda
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Onifade, Moshood
    Institute of Innovation, Science and Sustainability, Federation University Australia, Ballarat, VIC 3350, Australia.
    Simate, Isaac N.
    School of Engineering, University of Zambia, Great East Road, Lusaka 32379, Zambia.
    Lusambo, Edward
    School of Engineering, University of Zambia, Great East Road, Lusaka 32379, Zambia.
    Dynamic Simulation of Heat Distribution and Losses in Cement Kilns for Sustainable Energy Consumption in Cement Production2025Inngår i: Sustainability, E-ISSN 2071-1050, Vol. 17, nr 2, artikkel-id 553Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Sustainable energy consumption in cement production involves practises and strategies aimed at reducing energy use and minimising environmental impact. The efficiency of a cement kiln is dependent on the kiln design, fuel type, and operating temperature. In this study, a dynamic simulation analysis is used to investigate heat losses and distribution within kilns with the aim of improving energy efficiency in cement production. This study used Computational Fluid Dynamics (CFD) with Conjugate Heat Transfer, Turbulent Flow, and the Realisable k−ϵ turbulence model to simulate heat transfer within the refractory and wall systems of the kiln, evaluate the effectiveness of these systems in managing heat losses, and establish the relationship between the heat transfer coefficient (HTC) and the velocities of solid and gas phases. The simulation results indicate that a temperature gradient from the kiln’s interior to its exterior is highly dependent on the effectiveness of refractory lining in absorbing and reducing heat transfer to the outer walls. The results also confirm that different thermal profiles exist for clinker and fuel gases, with clinker temperatures consistently peaking at approximately 1450 °C, an essential condition for optimal cement-phase formation. The results also indicate that phase velocities significantly influence heat absorption and transfer. Lower velocities, such as 0.2 m/s, lead to increased heat absorption, but also elevate heat losses due to prolonged exposure. The relationship between the heat transfer coefficient (HTC) and the velocities of solid and gas phases also indicates that higher velocities improve HTC and enhance overall heat transfer efficiency, reducing energy demand.

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  • Mousavi, Milad
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Azarnia, Mahsa
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Zhong, Jin
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap. Department of Electrical and Electronic Engineering, University of Hong Kong, Hong Kong.
    Rönnberg, Sarah
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Maximization of renewable generation hosting capacity in power transmission grids considering participation in energy and flexibility markets: A bilevel optimization model2025Inngår i: Sustainable Energy, Grids and Networks, E-ISSN 2352-4677, Vol. 41, artikkel-id 101633Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Investment in renewable energy generation is integral to transitioning to sustainable power and energy systems. In this regard, the concept of hosting capacity (HC) is a useful tool for renewable generation investors and system operators to identify the maximum quantity of connected renewable resources without modification or strengthening of the grid. However, a considerable part of the extant research addresses the technical requirements of the problem in distribution systems while neglecting the transmission system and market constraints. Renewable generation uptake has reduced reliance on fossil fuel-based resources in the power sector, while also demonstrating capability to address the flexibility needs of the system. This paper proposes a market-based approach for maximizing renewable generation HC in transmission systems considering both energy and flexibility markets. To this end, a bilevel optimization problem is developed to study the profitability of maximizing renewable generation HC. In the upper-level problem, an HC maximization is developed with respect to the non-negative profitability of the new generation investment. The lower-level problem addresses social welfare maximization of energy and flexibility markets in which new renewable energy generation can participate. The formulations are transferred into a single-level mixed-integer linear programming (MILP) problem to avoid the nonlinearity of the bilevel model. The proposed model is applied to a 2-bus illustrative example and the IEEE 24-bus reliability test system (RTS). The results demonstrate that renewable generation units can improve their profitability by participating in the flexibility market and thereby increase the renewable generation HC from a market perspective.

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  • Frid, Moa
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik, Pedagogik, språk och ämnesdidaktik.
    Storying teaching together and with preschool practitioners: Renegotiating shapes of teaching in preschool education2025Inngår i: Contemporary Issues in Early Childhood, E-ISSN 1463-9491Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper explores and renegotiates the shapes of teaching in preschool education. Therefore, I engage in storytelling drawing from Haraway and create encounters together and with preschool practices and practitioners in connection to a policy change that introduced teaching into the Swedish preschool curriculum. This multiple inquiry complexifies teaching, starting with the preschool practitioners’ questions and concerns about teaching in preschool. Through stories, teaching takes both place and space in preschool education, challenging and confirming ideas and traditions on how to do preschool. Teaching takes multiple shapes and becomes a practice that extends beyond a specific event, encompassing both preparatory planning and subsequent reflections, as well as the continued process, intertwined with global trends of formalising early childhood education. Resisting a simplified story of the purpose of preschool education, I propose storytelling as a way to acknowledge teaching in preschool practices.

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  • Fernández, Shai
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Bodin, Ulf
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, EISLAB.
    Synnes, Kåre
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    A Framework for Sustainable and Fair Demand-Supply Matchmaking Through Auctioning2025Inngår i: Sustainability, E-ISSN 2071-1050, Vol. 17, nr 2, artikkel-id 572Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Environmental sustainability and fairness in auction systems are becoming increasingly important as systems evolve with the integration of digital technologies. This paper introduces a novel demand-supply matchmaking (DSM) framework designed to improve fairness and sustainability in auction environments, aligning with the principles of the circular economy. The framework addresses key challenges in supply chain management, such as equitable resource distribution and the reduction of environmental footprints. The framework integrates key aspects of environmental impact assessments, fairness assessments, and behavioral analytics. This enables the simulation of bidder behavior and assessment of auction scenarios. Our simulation results demonstrate that the platform can promote sustainable, fair, and informed auction practices. By comparing our approach with existing tools, we highlight the advantages of using the DSM framework to improve sustainability and fairness in digital marketplaces. This work supports the development of platforms that integrate economic efficiency with environmental responsibility and social equity.

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  • Rahmani, Ramin
    et al.
    CiTin—Centro de Interface Tecnológico Industrial, 4970-786 Arcos de Valdevez, Portugal; proMetheus—Instituto Politécnico de Viana do Castelo (IPVC), 4900-347 Viana do Castelo, Portugal.
    Bashiri, Bashir
    Institute of Chemistry and Biotechnology, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia; TFTAK, Mäealuse 2/4 B, 12618 Tallinn, Estonia.
    Lopes, Sérgio I.
    CiTin—Centro de Interface Tecnológico Industrial, 4970-786 Arcos de Valdevez, Portugal; ADiT-Lab, Instituto Politécnico de Viana do Castelo (IPVC), 4900-347 Viana do Castelo, Portugal.
    Hussain, Abrar
    Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia; Institute of Sustainable Building Materials and Engineering Systems, Faculty of Civil and Mechanical Engineering, Riga Technical University, Kipsalas iela 6A, LV-1048 Riga, Latvia.
    Maurya, Himanshu S.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Vilu, Raivo
    Institute of Chemistry and Biotechnology, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia; TFTAK, Mäealuse 2/4 B, 12618 Tallinn, Estonia.
    Sustainable Additive Manufacturing: An Overview on Life Cycle Impacts and Cost Efficiency of Laser Powder Bed Fusion2025Inngår i: Journal of Manufacturing and Materials Processing, E-ISSN 2504-4494, Vol. 9, nr 1, artikkel-id 18Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This overview study investigates integrating advanced manufacturing technologies, specifically metal additive manufacturing (AM) and laser powder bed fusion (LPBF) processes, within Industry 4.0 and Industry 5.0 frameworks, to enhance sustainability and efficiency in industrial production and prototyping. The manufacturing sector, a significant contributor to global greenhouse gas emissions and resource consumption, is increasingly adopting technologies that reduce environmental impact while maintaining economic growth. Selective laser melting (SLM), as the subsection LPBF technologies, is highlighted for its capability to produce high-performance, lightweight, and complex components with minimal material waste, thus aligning with circular economy goals for metal alloys. Life cycle assessment (LCA) and life cycle costing (LCC) analyses are essential methods for evaluating the sustainability of any new technology. Sustainable technologies could support the concepts of the factory of the future (FoF), fulfilling the requirements of digital transformation and digital twins. This overview study reveals that implementing AM—specifically SLM—has the potential to reduce the environmental impact of manufacturing. It underscores the ability of these technologies to promote sustainable and efficient manufacturing practices, thereby accelerating the shift from Industry 4.0 to Industry 5.0.

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  • Krikigianni, Eleni
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Antoniadis, Kyriakos
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Christakopoulos, Paul
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Rova, Ulrika
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Matsakas, Leonidas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Patel, Alok
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Strategic bioprocessing of A. protothecoides and C. sorokiniana using renewable feedstocks for targeted bioproduct and biodiesel generation2025Inngår i: Energy Conversion and Management: X, E-ISSN 2590-1745, Vol. 26, artikkel-id 100896Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The focus on sustainability and circular economy renders the microalgal biorefinery concept highly attractive. Although the diversity of microalgal composition makes them ideal feedstocks, their metabolic versatility challenges bioprocess optimization. To address this, an integrated, strain-specific approach was used to evaluate key cultivation parameters (nitrogen source, C/N ratio, and light intensity) as their interactions affect growth performance and biochemical composition. Heterotrophic cultivation of A. protothecoides (AP) and C. sorokiniana (CS) in glucose showed enhanced cell growth with organic N-sources. Biomass was consistently elevated across C/N ratios from 5 to 60 with corn steep liquor (CSL) (8.1 g L-1) and yeast extract (YE) (7.0 g L-1), while with urea it maximized at C/N 5 (6.2 g L-1). Protein synthesis increased at C/N 5, whereas lipid accumulation at C/N 60. Beechwood hydrolysate, a renewable glucose alternative, produced an average of 4.1 g L-1 protein (C/N 5) and 3.5 g L-1 lipids (C/N 60) between YE and CSL. Mixotrophic cultivation indicated better photosynthetic adaptation of AP at C/N 5, yielding 13.2 g L-1 biomass at 400 μmol m-2 s-1, whereas at C/N 60 growth was favored at 50 μmol m-2 s-1. The fatty acid profile of microalgal oil revealed de novo biosynthesis of odd-chain fatty acids at C/N 5 in both cultivation modes, while biodiesel-grade lipids produced in heterotrophic condition. These findings advance microalgal bioprocessing by emphasizing the importance of fine-tuning cultivation strategies and utilizing renewable nutrients to maximize resource efficiency and optimize the biosynthesis of valuable bioproducts, such as proteins, pigments, carbohydrates, and high-quality lipids.

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  • Maurya, Himanshu Singh
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, Tallinn, 19086, Estonia.
    Marczyk, J.
    Faculty of Materials Engineering and Physics, Cracow University of Technology, Warszawska 24, Cracow, 31-155, Poland; Faculty of Mechanical Engineering, Department of Applied Informatics, Cracow University of Technology, Warszawska 24, 31-155, Cracow, Poland.
    Juhani, K.
    Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, Tallinn, 19086, Estonia.
    Sergejev, F.
    Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, Tallinn, 19086, Estonia.
    Kumar, R.
    Laboratory for Tribology and Interface Nanotechnology, Faculty of Mechanical Engineering, University of Ljubljana, Bogišićeva 8, Ljubljana, 1000, Slovenia.
    Hussain, A.
    Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, Tallinn, 19086, Estonia.
    Akhtar, Farid
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Hebda, M.
    Faculty of Materials Engineering and Physics, Cracow University of Technology, Warszawska 24, Cracow, 31-155, Poland.
    Prashanth, K. G.
    Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, Tallinn, 19086, Estonia; CBCMT, School of Mechanical Engineering, Vellore Institute of Technology, Vellore, 630014, Tamil Nadu, India.
    Binder jetting 3D printing of green TiC-FeCr based cermets- Effect of sintering temperature and systematic comparison study with Laser powder bed fusion fabricated parts2025Inngår i: Materials Today Advances, E-ISSN 2590-0498, Vol. 25, artikkel-id 100562Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The advancement of modern 3D printing technologies has opened the possibilities to fabricate different spectrums of materials using these technologies. Binder jetting 3D printing is a shaping-debinding-sintering-based Additive manufacturing process that selectively fabricates the parts in a layer-by-layer fashion using the local imprinting of polymeric binder. This study aims to develop cobalt and nickel-free TiC-FeCr-based cermets that will contribute to the development of cermets towards green and cost-efficient materials. An effective approach to increase the densities of printed parts was to replace unimodal powder feedstocks with bimodal powders. Therefore, this work employed bimodal spherical powder (TiC and 430L ferritic stainless steel) to promote better densification of the cermet parts. Liquid phase vacuum sintering has been performed with different sintering temperatures to consolidate the cermet parts. Detailed analyses of the microstructure evolution, phase formation, and mechanical properties (hardness and fracture toughness) have been conducted. Further, thermodynamic simulations were conducted to calculate the phase diagram of the proposed cermet using the Thermo-Calc program. Microstructural analysis of consolidated cermets reveals a direct correlation between sintering temperature and carbide grain size, affecting their mechanical and physical properties. The best hardness and fracture toughness properties of TiC-FeCr-based cermets are 1102 ± 13 HV30 and 12.74 ± 1.38 MPa m1/2 respectively, were obtained after sintering at 1450 °C. Moreover, a systematic comparison is conducted with the same cermet composition fabricated with different additive manufacturing processes based on Laser powder bed fusion and Binder jetting 3D printing technology, demonstrating the potential and limitations of both technologies to fabricate brittle materials such as cermets.

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  • Cao, Jie
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Wang, Chao
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Gonzalez-Libreros, Jaime
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Tu, Yongming
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Southeast University, Nanjing, China.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Scaling Effect on Mechanical Property of Calcium Silicate Hydrate in Cement Using Reactive Molecular Dynamics2025Inngår i: The 1st International Conference on Net-Zero Built Environment: Innovations in Materials, Structures, and Management Practices / [ed] Mahdi Kioumarsi; Behrouz Shafei, Springer Nature, 2025, s. 293-302Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Molecular dynamics simulations have been increasingly employed to investigate the mechanical properties of cement hydrates at the nanoscale. This technique deepens the understanding of cement-based materials, yet correlating these nanoscale findings with larger scale experiments remains a challenge, particularly due to scaling effects. This study focuses on the scaling impact on calcium silicate hydrate (C-S-H). Two types of C-S-H models were constructed: one with defective silicate chains and the other without. Each model includes three sub-models of varying sizes. Under uniaxial tension along silicon chain direction, the stress and strain responses were recorded. The results show that at the nanoscale, model correction such as silicon chain breakage has a greater impact on the elastic modulus and tensile strength than model size. Additionally, the stress–strain curve obtained during the tension process needs to be corrected before comparison with stress–strain on other scales. The findings provide crucial insights into the mechanical behavior of C-S-H at the nanoscale and offer a theoretical basis for bridging the gap between nanoscale simulations and larger scale experimental results. 

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  • Robertson, Jeandri
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Industriell ekonomi. School of Management Studies, University of Cape Town, Cape Town, South Africa.
    Botha, Elsamari
    UC Business School, University of Canterbury, Christchurch, New Zealand.
    Oosthuizen, Kim
    University of Stellenbosch Business School, Cape Town, South Africa.
    Montecchi, Matteo
    King's Business School, King's College London, London, UK.
    Managing change when integrating artificial intelligence (AI) into the retail value chain: The AI implementation compass2025Inngår i: Journal of Business Research, ISSN 0148-2963, E-ISSN 1873-7978, Vol. 189, artikkel-id 115198Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In a complex business environment, the quest for intelligent solutions has placed artificial intelligence (AI) at the center of many operational business decisions, particularly within the retail sector. As retailers’ investment in AI disrupts value chains, they must adapt to organizational changes, yet limited research exists on how to address organizational challenges when integrating AI into the retail value chain. Using 23 expert interviews with retail executives and AI vendors, this study investigates the socio-technical challenges retailers encounter when integrating AI into their value chain and offers strategies to address these organizational hurdles. We identify micro-, meso-, and macro-level factors impacting AI implementation in retail and propose an AI Implementation Compass to address the change management process. This framework serves as a guide to navigate the complex landscape of AI adoption, emphasizing a holistic approach that considers not only internal organizational dynamics, but also external market forces.

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  • Upadhyayula, Venkata K.K.
    et al.
    Department of Chemistry, Umeå University, SE 90187, Umeå, Sweden.
    Yacout, Dalia M.M.
    Department of Chemistry, Umeå University, SE 90187, Umeå, Sweden; Department of Energy and Technology, Swedish University of Agricultural Sciences (SLU), SE-750 07, Uppsala, Sweden.
    Latham, Kenneth G.
    Department of Chemistry, Umeå University, SE 90187, Umeå, Sweden.
    Jansson, Stina
    Department of Chemistry, Umeå University, SE 90187, Umeå, Sweden.
    Rova, Ulrika
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Christakopoulos, Paul
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Matsakas, Leonidas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Organosolv lignin carbon fibers and their prospective application in wind turbine blades: An environmental performance assessment2025Inngår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 491, artikkel-id 144825Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Lignin is a potential sustainable alternative to polyacrylonitrile (PAN) precursor for the production of carbon fibers. The high purity lignin extracted from residual forest biomass via organosolv process undergoes stabilization and carbonization treatment to produce carbon fibers. Recent developments suggest the potential of producing organosolv lignin carbon fibers (OLCF) with competing mechanical properties similar to PAN carbon fibers. This is likely to enable the use of OLCF in structurally demanding applications such as wind turbine blades. In this work, a life cycle assessment (LCA) is performed with a threefold objective. First, the environmental footprint of OLCF is quantified and results are compared with PAN-CF produced in Sweden and elsewhere in Europe i.e., electricity demands met by European average electrical grid (RER). Second, the environmental performance of OLCF reinforced wind turbine blades (referred as BIOMAT) to be installed in 0.8 MW capacity is evaluated against incumbent variants: glass fiber turbine blade (GFTB), PAN-CF based turbine blades manufactured in Sweden (CFTB-SE), and other parts of Europe (CFTB-RER). Finally, the total environmental externality costs (EEC) of these blades and corresponding lifetime electricity generation when they are installed in 0.8 MW capacity wind turbine blade are calculated. Our results indicate that the environmental impacts of OLCF are lower by 71–94% than PAN-CF-RER in nine, and lower by 43–90% than PAN-CF-SE in six out of ten impact categories quantified respectively. BIOMAT blades also have better overall environmental performance than existing blade variants and particularly lucrative because of their negative total climate change impact. The total EEC of BIOMAT blades is 74%, 83% and 88% lower than GFTB, CFTB-SE and CFTB-RER respectively. Correspondingly, the total EEC of lifetime electricity generated by wind turbine equipped with BIOMAT blades is 11%, 17% and 23% lower than the respective blade variants.

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  • Yousefdeh, Seyed Alireza Ghasempour
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Oyelere, Solomon Sunday
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap. Department of Computer Science, University of Exeter, Exeter, United Kingdom.
    Investigating co-presence and collaboration dynamics in realtime virtual reality user interactions2024Inngår i: Frontiers in Virtual Reality, E-ISSN 2673-4192, Vol. 5, artikkel-id 1478481Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    As Virtual Reality (VR) technologies advance and gain popularity, their potential as powerful tools for collaboration is increasingly recognized. VR facilitates interaction with the virtual presence of individuals who are not physically co-located. Understanding the dynamics of user interactions and the cognitive perception of virtual presence quality is essential for this technology’s progression. This paper introduces CoCoVR, a VR measurement method for measuring the sense of co-presence and collaboration quality among users through real-time data collection and analysis. CoCoVR is evaluated across various scenarios to understand user interactions in VR under different conditions. An extensive analysis of recent literature has been performed that identified avatar realism and communication as two key factors influencing co-presence and collaboration. The experiment includes a custom VR application, the Soma cube puzzle, and real-time sensors. A between-subject experiment was conducted to collect and analyzes real-time data on collaboration and co-presence. This study integrates both objective and subjective measures, offering deeper insights into the immersive experience and its impact on collaborative tasks. The findings show that avatar realism enhances the feeling of co-presence and that communication methods substantially improve collaboration. Additionally, the study found that measuring physiological responses can serve as a novel method for evaluating the quality of user collaborations.

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  • Shahzad, Tahreem
    et al.
    Department of Chemistry, University of Narowal, Narowal 51600, Pakistan.
    Nawaz, Sajawal
    Department of Physics, University of Padua, 35122 Padua, Italy.
    Jamal, Hasan
    Division of Energy Technology, Daegu Gyeongbuk Institute of Science & Technology, 333, Techno Jungang-Daero, Hyeonpung-Myeon, Dalseong-Gun, Daegu, 42988, Republic of Korea.
    Shahzad, Taiba
    Department of Bio-Technology, University of Narowal, Narowal 51600, Pakistan.
    Akhtar, Farid
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Division of Materials Science, Luleå University of Technology, 97187 Luleå, Sweden.
    Kamran, Urooj
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Institute of Advanced Machinery Design Technology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea.
    A Review on Cutting-Edge Three-Dimensional Graphene-Based Composite Materials: Redefining Wastewater Remediation for a Cleaner and Sustainable World2025Inngår i: Journal of Composites Science, E-ISSN 2504-477X, Vol. 9, nr 1, artikkel-id 18Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Three-dimensional (3D) graphene-based composite materials (3D GBCMs) have emerged as promising candidates for addressing critical challenges in water pollution remediation. This review selectively highlights the recent advancements in the application of 3D GBCMs to remove a wide range of contaminants, including heavy metals, dyes, salts, and pharmaceutical residues, from water. They owe their efficacy to their large surface area, interconnected porous structure, and functionalization potential. Three-dimensional GBCMs are promising materials for water filtration, offering capabilities such as heavy metal ion adsorption, the photocatalytic degradation of organic pollutants, and advanced desalination techniques like capacitive deionization (CDI) and solar desalination, thus providing sustainable solutions for obtaining freshwater from saline sources. Additionally, the factors influencing the pollutant removal capacities of 3D GBCMs, such as their material morphology, particle size, and porosity, are briefly discussed. Notably, the effect of the particle size on pollutant removal has not been extensively studied, and this review addresses that gap by exploring it in detail. Future research directions are also proposed, emphasizing the optimization and broader application of 3D GBCMs in environmental remediation. This review aims to provide valuable insights into the design and practical implementation of 3D GBCMs, offering guidance for their continued development in sustainable water treatment.

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  • Lindberg, Johanna
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Digitala tjänster och system.
    Nolin, Marie ()
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Digitala tjänster och system.
    Lundberg-Nilsson, Sofie ()
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Digitala tjänster och system.
    Eklund, Marina ()
    Region Norrbotten, Sweden.
    Gelter, Jennie ()
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Digitala tjänster och system.
    DigiBy: Slutrapport till Tillväxtverket2024Rapport (Annet (populærvitenskap, debatt, mm))
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  • Sui, Yikun
    et al.
    School of Resource and Safety Engineering, Central South University, Changsha 410083, China.
    Zhou, Zhiyong
    School of Resource and Safety Engineering, Central South University, Changsha 410083, China.
    Zhao, Rui
    School of Resource and Safety Engineering, Central South University, Changsha 410083, China.
    Yang, Zheng
    School of Resource and Safety Engineering, Central South University, Changsha 410083, China.
    Zou, Yang
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Open-Pit Bench Blasting Fragmentation Prediction Based on Stacking Integrated Strategy2025Inngår i: Applied Sciences, E-ISSN 2076-3417, Vol. 15, nr 3, artikkel-id 1254Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The size distribution of rock fragments significantly influences subsequent operations in geotechnical and mining engineering projects. Thus, accurate prediction of this distribution according to the relevant blasting design parameters is essential. This study employs artificial intelligence methods to predict the fragmentation of open-pit bench blasting. The study employed a dataset comprising 97 blast fragment samples. Random forest and XGBoost models were utilized as base learners. A prediction model was developed using the stacking integrated strategy to enhance predictive performance. The model’s performance was evaluated using the coefficient of determination (R2), the mean square error (MSE), the root mean square error (RMSE), and the mean absolute error (MAE). The results indicated that the model achieved the highest prediction accuracy, with an R2 of 0.943. In the training set, the model achieved MSE, RMSE, and MAE values of 0.00269, 0.05187, and 0.03320, while in the testing set, these values were 0.00197, 0.04435, and 0.03687, respectively. The model was validated using five sets of actual blasting block data from a northeastern mining area, which yielded more accurate prediction results. These findings demonstrate that the stacking strategy effectively enhances the prediction performance of a single model and offers innovative approaches to predicting blasting block size.

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  • Compierchio, Angelo
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Tretten, Phillip
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Människa och teknik.
    Illankoon, Prasanna
    Department of Management of Technolog, University of Moratuwa, Moratuwa 10400, Sri Lanka.
    The Quest for the Transition of Inalienable Rights from Humansto Intelligent Machines2025Inngår i: Philosophies, E-ISSN 2409-9287, Vol. 10, nr 19, artikkel-id 10010019Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Intelligent machines (IMs), which have demonstrated remarkable innovations over time, require adequate attention concerning the issue of their duty–rights split in our current society. Although we can remain optimistic about IMs’ societal role, we must still determine their legal-philosophical sense of accountability, as living data bits have begun to pervade our lives. At the heart of IMs are human characteristics used to self-optimize their practical abilities and broaden their societal impact. We used Kant’s philosophical requirements to investigate IMs’ moral dispositions, as the merging of humans with technology has overwhelmingly shaped psychological and corporeal agential capacities. In recognizing the continuous burden of human needs, important features regarding the inalienability of rights have increased the individuality of intelligent, nonliving beings, leading them to transition from questioning to defending their own rights. This issue has been recognized by paying attention to the rational capacities of humans and IMs, which have been connected in order to achieve a common goal. Through this teleological scheme, we formulate the concept of virtual dignity to determine the transition of inalienable rights from humans to machines, wherein the evolution of IMs is essentially imbued through consensuses and virtuous traits associated with human dignity.

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  • Reinhold, Mats
    et al.
    Department of Psychology, Umeå University, Umeå, Sweden; Umeå Center for Gender Studies, Umeå University, Umeå, Sweden.
    Keisu, Britt-Inger
    Department of Sociology, Umeå university, Umeå, Sweden.
    Lundmark, Robert
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik, Hälsa, medicin och rehabilitering. Department of Psychology, Umeå University, Umeå, Sweden.
    Stenling, Andreas
    Department of Psychology, Umeå University, Umeå, Sweden.
    Tafvelin, Susanne
    Department of Psychology, Umeå University, Umeå, Sweden.
    “My team made me do it”: the differential influence of team amotivation on leaders’ destructive leadership behavior, from a gender perspective2025Inngår i: Cogent Psychology, E-ISSN 2331-1908, Vol. 12, nr 1, artikkel-id 2456333Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Destructive leadership does not occur in a vacuum; rather, these behaviors are part of a social process in which leader and follower interact and influence each other. Still, knowledge regarding followers’ behaviors as antecedents to destructive leadership behavior is limited, even more so from a gender perspective. In this study, we investigate the relationship between perceived lack of team motivation and destructive leadership behavior, with the leader’s gender as a moderator. Together with Statistic Sweden, we collected data using a two-wave survey design. We included 784 participants in the analysis, using structural equation modeling (SEM). The results showed that perceived lack of team motivation was associated with active and passive destructive leadership behaviors. Beyond that, the leader’s gender moderated the relationship between leaders’ perception of team amotivation and active destructive leadership. The results show that male leaders are more prone to act destructively when they perceive a lack of team motivation. These results suggest that male leaders may be more susceptible to engaging in destructive leadership behaviors due to identity threat than female leaders. Therefore, we examine how the construction of gender and identity and the close association between masculinity and leader identity contribute to the risk of engaging in destructive leadership behavior.

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  • Näsman, Mattias
    et al.
    Umeå University, 901 87 Umeå, Sweden.
    Bergquist, Ann-Kristin
    Uppsala University, 753 10 Uppsala, Sweden.
    Björling, Nils
    Chalmers University, 412 96 Gothenburg, Sweden.
    Eriksson, Madeleine
    Umeå University, 901 87 Umeå, Sweden.
    Hane-Weijman, Emelie
    Umeå University, 901 87 Umeå, Sweden.
    Liliequist, Evelina
    Umeå University, 901 87 Umeå, Sweden.
    Lindmark, Magnus
    Umeå University, 901 87 Umeå, Sweden.
    Lundberg, Johan
    Umeå University, 901 87 Umeå, Sweden.
    Lundgren, Anna-Sofia
    Umeå University, 901 87 Umeå, Sweden.
    Müller, Dieter K
    Umeå University, 901 87 Umeå, Sweden.
    Rataj, Marcin
    Umeå University, 901 87 Umeå, Sweden.
    Rönnblom, Malin
    Karlstad University, 651 88 Karlstad, Sweden.
    Scott, David
    Karlstad University, 651 88 Karlstad, Sweden.
    Viklund, Roine
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Samhällsvetenskap.
    Eriksson, Rikard
    Umeå University, 901 87 Umeå, Sweden.
    A promised land? Second summary of the research program2024Rapport (Annet vitenskapelig)
    Abstract [en]

    This research note contains an update of the research program “A promised land? Drivers, challenges and opportunities related to the (green) industrialization of Northern Sweden,” (nr. M22-0029) awarded by the Swedish Riksbankens Jubileumsfond’s in 2022. The document summarizes work in progress and is updated annually in different versions according to the requirements of the program. This interdisciplinary program aims to understand the economic, social, and political challenges and opportunities of the ongoing industrial transformation in northern Sweden. A key element of the program is to identify drivers, obstacles, and preconditions in a historical, present, and forward-looking process-perspective.

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  • Kazieva, Victoria
    et al.
    Mid Sweden University, Department of Communication Quality Management and Information Systems, Sundsvall, Sweden.
    Grosse, Christine
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Digitala tjänster och system. Mid Sweden University, Department of Communication Quality Management and Information Systems, Sundsvall, Sweden.
    Larsson, Aron
    Stockholm University, Department of Computer and System Sciences, 164 07 Kista, Sweden; Mid Sweden University, Department of Communication Quality Management and Information Systems, Sundsvall, Sweden.
    Towards a unified regional vision: simulation to foster cross-municipal cooperation and planning2024Inngår i: Insights into Regional Development, E-ISSN 2669-0195, Vol. 6, nr 4, s. 54-81Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Simulation modeling is an effective tool that enables knowledge-based approaches to support decision-making for complex problems. Agent-based modeling (ABM) simulation is particularly powerful in the visualization of macro-outcomes of individual and group-specific behaviour, for example in urban and regional planning. However, the adoption of ABM in practice often overlooks its capabilities. Ineffective planning sets sparsely populated remote regions to risk of suffering from long-term consequences, such as population decline. In these settings, it is important to bring municipalities into a dialogue to share the advantages of common planning at a regional scale for their mutual advancement. This study aims to explore the potential of applying ABM and its visual capabilities to support regionwide planning. For this purpose, we develop a model of accessibility of a Swedish region to enhance awareness of common problems with regional accessibility and lift the planning focus from a local scale to a regional one. The model in this paper draws on empirical data from interactions with planners in a region of six municipalities with varying degrees of urbanization in a sparsely populated remote area in Sweden. The model visualizes the dynamic changes in accessibility and demonstrates how destination clustering outplays on a higher system level usually overlooked in planning. The simulation of the case shows that aggravated agglomeration effects will prevent municipalities from developing their centers if they do not consider the opportunities in neighbouring areas within the same region. The paper contributes insights that stimulate the adoption of simulation in complex domains, such as public planning that seeks to align local and regional perspectives.

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  • Chen, Yifeng
    et al.
    Institute of Chemical Industry of Forest Products, CAF, National Engineering Laboratory for Biomass Chemical Utilization, Key and Open Laboratory of Forest Chemical Engineering, SFA, Key Laboratory of Biomass Energy and Material, Nanjing 210042, China.
    Yin, Haoran
    Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China.
    Wen, Shitao
    Institute of Chemical Industry of Forest Products, CAF, National Engineering Laboratory for Biomass Chemical Utilization, Key and Open Laboratory of Forest Chemical Engineering, SFA, Key Laboratory of Biomass Energy and Material, Nanjing 210042, China.
    Zhang, Weiyue
    Zhejiang Jizhu Biotechnology Co., LTD, Huzhou 313300, China.
    Hu, Shengchun
    Institute of Chemical Industry of Forest Products, CAF, National Engineering Laboratory for Biomass Chemical Utilization, Key and Open Laboratory of Forest Chemical Engineering, SFA, Key Laboratory of Biomass Energy and Material, Nanjing 210042, China.
    Sun, Kang
    Institute of Chemical Industry of Forest Products, CAF, National Engineering Laboratory for Biomass Chemical Utilization, Key and Open Laboratory of Forest Chemical Engineering, SFA, Key Laboratory of Biomass Energy and Material, Nanjing 210042, China.
    Jiang, Jianchun
    Institute of Chemical Industry of Forest Products, CAF, National Engineering Laboratory for Biomass Chemical Utilization, Key and Open Laboratory of Forest Chemical Engineering, SFA, Key Laboratory of Biomass Energy and Material, Nanjing 210042, China.
    Ji, Xiaoyan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Biogas upgrading using aqueous bamboo-derived activated carbons2025Inngår i: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 419, artikkel-id 132055Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    CO2/CH4 separation is crucial for biogas upgrading. In this study, the bamboo-derived activated carbons (BACs) were prepared with different ratios of potassium hydroxide (KOH)/bamboo charcoal (BC), and the hybrid sorbents of aqueous BACs were developed for CO2/CH4 separation. Both the gas solubility and sorption rate were measured, and Henry’s constant and liquid-side mass-transfer coefficient as well as the CO2/CH4 selectivity were calculated. Meanwhile, the comprehensive performances of aqueous BACs were evaluated using a novel index, and the cost of biogas upgrading using the aqueous BACs was estimated and compared to the commercialized technology. The results proved the effectiveness of aqueous BACs, and the comprehensive performance of 7.0 wt% aqueous BAC with the KOH/BC mass ratio of 2:1 was 4.2 times than that of H2O, having the potential to decrease the average CO2/CH4 separation cost by 65.0% compared to the commercialized technology.

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  • Dorigo, Tommaso
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, EISLAB. INFN - Sezione di Padova, Padova, Italy; Universal Scientific Education and Research Network, Italy.
    Brown, Gary D.
    Universal Scientific Education and Research Network, Italy; Bush School of Government and Public Service, Texas A&M University College Station, Texas, USA.
    Casonato, Carlo
    Faculty of Law, University of Trento, Trento, Italy.
    Cerda, Artemi
    Universal Scientific Education and Research Network, Italy; Departament de Geografia, Soil Erosion and Degradation Research Group, Universitat de València, Valencia, Spain.
    Ciarrochi, Joseph
    Australian Catholic University, Institute of Positive Psychology and Education, Sydney, Australia.
    Lio, Mauro Da
    Department of Industrial Engineering, Università degli Studi di Trento, Trento, Italy.
    D'souza, Nicole
    Department of Neuroscience, College of Humanities, Arts, and Social Sciences (CHASS), University of California Riverside, USA; Systems Neural Engineering Laboratory, University of Southern California Viterbi School of Engineering, USA.
    Gauger, Nicolas R.
    Chair for Scientific Computing, University of Kaiserslautern-Landau (RPTU), Kaiserslautern, Germany.
    Hayes, Steven C.
    Universal Scientific Education and Research Network, Italy; Department of Psychology, University of Nevada, Reno, Nevada, USA Institute for Better Health, Santa Rosa, California, USA.
    Hofmann, Stefan G.
    Department of Psychology, Philipps University Marburg, Marburg, Germany.
    Johansson, Robert
    Department of Psychology, Stockholm University, Stockholm, Sweden.
    Liwicki, Marcus
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, EISLAB.
    Lotte, Fabien
    Universal Scientific Education and Research Network, Italy; Inria Center, University of Bordeaux / LaBRI, Talence, France.
    Nieto, Juan J.
    Universal Scientific Education and Research Network, Italy; Department of Statistics, Mathematical Analysis and Optimization, Galician Centre for Mathematical Research and Technology (CITMAga), University of Santiago de Compostela, Santiago de Compostela, Spain.
    Olivato, Giulia
    Faculty of Law, University of Trento, Trento, Italy.
    Parnes, Peter
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Perry, George
    Universal Scientific Education and Research Network, Italy; Department of Neuroscience, Developmental and Regenerative Biology, University of Texas at San Antonio, San Antonio, Texas, USA.
    Plebe, Alice
    Department of Computer Science, University College London, London, United Kingdom.
    Rao, Idupulapati M.
    Universal Scientific Education and Research Network, Italy; International Center for Tropical Agriculture (CIAT), Cali, Colombia International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya.
    Rezaei, Nima
    Universal Scientific Education and Research Network, Italy; Research Center for Immunodeficiencies, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran.
    Sandin, Fredrik
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, EISLAB.
    Ustyuzhanin, Andrey
    Constructor University, Bremen, Germany; Institute for Functional Intelligent Materials, National University of Singapore, Singapore, Singapore.
    Vallortigara, Giorgio
    Centre for Mind/Brain Sciences, University of Trento, Rovereto, Italy.
    Vischia, Pietro
    Universal Scientific Education and Research Network, Italy; Universidad de Oviedo and ICTEA, Oviedo, Spain.
    Yazdanpanah, Niloufar
    Universal Scientific Education and Research Network, Italy; Research Center for Immunodeficiencies, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran.
    Artificial Intelligence in Science and Society: the Vision of USERN2025Inngår i: IEEE Access, E-ISSN 2169-3536Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The recent rise in relevance and diffusion of Artificial Intelligence (AI)-based systems and the increasing number and power of applications of AI methods invites a profound reflection on the impact of these innovative systems on scientific research and society at large. The Universal Scientific Education and Research Network (USERN), an organization that promotes initiatives to support interdisciplinary science and education across borders and actively works to improve science policy, collects here the vision of its Advisory Board members, together with a selection of AI experts, to summarize how we see developments in this exciting technology impacting science and society in the foreseeable future. In this review, we first attempt to establish clear definitions of intelligence and consciousness, then provide an overviewof AI’s state of the art and its applications. A discussion of the implications, opportunities, and liabilities of the diffusion of AI for research in a few representative fields of science follows this. Finally, we address the potential risks of AI to modern society, suggest strategies for mitigating those risks, and present our conclusions and recommendations.

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  • Sundström, Anna E.
    et al.
    Department of Psychology, Umeå University, Umeå, Sweden.
    Nordin, Maria
    Department of Psychology, Umeå University, Umeå, Sweden.
    Nordin, Steven
    Department of Psychology, Umeå University, Umeå, Sweden.
    Neely, Anna Stigsdotter
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik, Hälsa, medicin och rehabilitering. Department of Social and Psychological Studies, Karlstad University, Karlstad, Sweden.
    Gavelin, Hanna Malmberg
    Department of Psychology, Umeå University, Umeå, Sweden; Department of Public Health and Clinical Medicine, Section of Sustainable Health, Umeå University, Umeå, Sweden.
    Dimensionality, Sensitivity and Specificity of Different Versions of the Shirom-Melamed Burnout Questionnaire/Measure in Clinical and Non-Clinical Populations2025Inngår i: Stress and Health, ISSN 1532-3005, E-ISSN 1532-2998, Vol. 41, nr 1, artikkel-id e70001Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Shirom-Melamed Burnout Questionnaire/Measure (SMBQ/SMBM) is a self-report instrument frequently used for assessing degree of burnout and screening for stress-related exhaustion disorder. The aim of the present study was three-fold. First, to examine reliability and construct validity of different versions of SMBM with 6–22 items in a clinical context. Second, to examine the criterion validity by assessing sensitivity and specificity and determining clinical cut-offs for these versions of the SMBM, and third to examine the prevalence of burnout in a general population and primary care sample using the proposed cut-offs. Two Swedish samples were used for the first two purposes: a clinical sample of patients diagnosed with exhaustion disorder (n = 149), and a matched sample of healthy controls (n = 60). For the third purpose a sample from the general population (n = 3406), and a primary care clinical sample (n = 326) was used. The modified versions of the SMBM showed good internal consistency, construct validity, dimensionality and model fit on the clinical exhaustion disorder sample, as well as configural measurement invariance across clinical and non-clinical samples. The sensitivity (94.6%–95.3%) and specificity (93.3%–95.0%) in identifying cases with exhaustion disorder based on the cut-off of 4.0 for the 19-, 16- and 11-items versions, and on the cut-off of 3.75 for the 6-item version was high. The prevalence of burnout was 81.2% in the primary care sample and 16.6% in the general population sample. The findings indicate that the SMBM is a useful instrument for screening for exhaustion disorder and burnout.

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  • Johansson, Malin
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Samhällsvetenskap.
    Environmental law issues regarding PFAS pollution in waters around landfills in Sweden2023Konferansepaper (Annet vitenskapelig)
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  • Johansson, Oskar
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Samhällsvetenskap.
    End of Waste, Beginning of Resources2023Konferansepaper (Annet vitenskapelig)
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    Program
  • Birdsong, Björn K.
    et al.
    Department of Fibre and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Capezza, Antonio J.
    Department of Fibre and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Elf, Patric
    Department of Fibre and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Hedenqvist, Mikael S.
    Department of Fibre and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Nilsson, Fritjof
    Department of Fibre and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Olsson, Richard T.
    Department of Fibre and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Flexible fire-safe hybrid organic-inorganic cellulose aerogels from sol-gel casting2025Inngår i: RSC Sustainability, E-ISSN 2753-8125Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The flexibility of hybrid silicon-oxide cellulose aerogels was achieved through the formation of thin, uniform silica coatings on cellulose fibres, or local regions of a classical spherical aerogel (Kistler aerogel) combined with areas of less coated cellulose fibres, making use of the flexible properties of the cellulose nanofibres. Furthermore, the inclusion of cellulose during the sol–gel formation allowed the use of traditional freeze-drying instead of CO2 critical point drying as a method for the removal of the liquid phase. The silicon oxide morphologies revealed the possibility of fine-tuning the coating's structure by the choice of the silicon-oxide precursors. Using methyltrimethoxysilane (MTMS) resulted in the formation of classical aerogel or spherical particles, while the use of tetraethyl orthosilicate (TEOS) yielded “pearl-necklace” fibres, and the mix of (3-aminopropyl)triethoxysilane (APTES) with MTMS yielded smooth uniform coatings. The prepared coating morphologies markedly influenced the aerogel's properties (mechanical stiffness/flexibility, flame resistance and hydrophilicity). The silica coatings endured high-temperature exposure and the thermal removal of the cellulose template without substantial morphological changes was confirmed, showing the possibility to use cellulose as an effective template for the synthesis of silicon-oxide nanofibres. The possibility to selectively control aerogel properties already at the synthesis stage, using abundant and renewable materials together with the possibility of using more energy-conservative freeze-drying (rather than critical point drying), is a promising method for more sustainable aerogel preparation towards high-end commercial applications such as electrical fuel cell insulation.

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  • Merlo, Luisa
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Johansson, Charlotta
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Nilson, Finn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Chapman, David
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    State of the art for walking as a transport mode within 15-minute cities2025Inngår i: Urban, Planning and Transport Research, ISSN 2165-0020, Vol. 13, nr 1, artikkel-id 2456186Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Walking is well known for its societal benefits, including promoting sustainability, health, and environmental well-being. In recent years, urban planners and traffic designers have increased their focus on creating pedestrian-friendly zones. The 15-minute city concept, which gained recognition in recent years, emphasizes proximity, aiming to keep daily amenities close to residents to reduce travel time and encourage walking and cycling as modes of transport. This literature review, using an abductive qualitative approach, examines how the factors influencing planning for walking are addressed within the 15-minute city concept. The goal is to compile the state of knowledge and identify critical issues and priorities in the field of walking as a mode of transport. The findings are predominantly from China and Italy, and indicate a global concern about urban centres’ accessibility within the 15-minute city concept and highlight that walking is a multidisciplinary topic. However, the review reveals under-researched areas such as individual factors, smaller settlements, and lack of standardized methods. This stresses the need for further research to encourage walking and its multiple benefits.

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  • Shirzadegan, Shahin
    et al.
    Ramboll Sweden AB, Rock Engineering Division, Luleå, Sweden.
    Warema, Senzia
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Nordlund, Erling
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Zhang, Ping
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Yi, Changping
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Numerical Analysis of the Large-scale DynamicTest of Rock Support at Kiirunavaara mine –Improved Design2025Inngår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 15, nr 1, s. 39-69Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The numerical analysis results from an improved design of large-scale dynamic test of rock support (Test 6) is presented in this paper. The improved field test was designed based on the results obtained from field tests and the numerical analysis of the earlier tests (Tests 1 – 5) conducted at LKAB Kiirunavaara mine. The performed numerical analysis investigates how the improvements including minimizing the expansion of blasting gases into the burden, avoiding the complete damage of the burden, and creating sub-planar waves were achieved under the improved design of the test. Furthermore, the response of supported and unsupported excavations as well as the complex interaction of stress waves and rock support was numerically studied. The numerical analysis comprised of two stages (i) the explosion stage modelled with the finite element code LS-DYNA and (ii) the wave propagation stage which was modelled using UDEC with the results from LS-DYNA as input. The accuracy of the developed models was investigated by comparison of the UDEC models results to the data obtained from the field test. The numerical analysis results confirmed that the improved designed burden has assisted in reducing the areas of tensile yielding in the burden and as a result, the gas expansion and complete damage of the burden was avoided. The simulation results showed that the used support system (Swellex Mn 24 and reinforced shotcrete) has effectively limited the displacement of the test wall and prevented ejection during the dynamic loading. The combined numerical technique has shown its advantage when simulating blasting as well as interaction between waves and opening and it can thus be used as a tool for evaluating rock support performance.

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  • Shirzadegan, Shahin
    et al.
    Ramboll Sweden AB, Rock Engineering Division, Luleå, Sweden.
    Nordlund, Erling
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Zhang, Ping
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Yi, Changping
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Warema, Senzia
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Numerical Analysis of the Large-scale DynamicTests of Rock Support at Kiirunavaara mine2025Inngår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 15, nr 1, s. 1-37Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The numerical analysis of four dynamic large-scale field tests conducted at LKABKiirunavaara mine are presented in this paper. The aim was to numerically studythe behavior and response of the burden and the tested walls in field Tests 1, 2, 4and 5. For this purpose, two numerical methods were combined, i.e. the finiteelement code LS-DYNA and the distinct element code UDEC. The LS-DYNA wasused to calculate the blast load, and the UDEC was used to propagate the calculatedload in the model where the geological conditions of the test site and the installedrock support in the field tests were modelled. The model was calibrated bycomparing the velocity and displacement calculated on the surface of the opening,and the zones yielded in tension were used to study the failure mechanismdeveloped in the burden. The numerical models were able to mimic the behavior ofthe jointed rock mass and the rock support fairly well. It is concluded that thenumber of major joint sets was the main reason to the difference between the failuredevelopment in Tests 1 and 2 and Tests 4 and 5. The numerical analysis of Tests 1and 2 confirmed that the gas pressure in the vicinity of the test wall in those testswas minimum. In Tests 4 and 5, it was observed that, the generated fractures in theburden combined with the natural joint condition of the burden, increased thepossibility for blocks to rotate and move within the burden. The complete burdendamage in Tests 4 and 5 was concluded to be the be due to the ejection of rockblocks in the vicinity of the test wall upon the arrival of stress wave, and ejection ofthe remaining portion of the rock blocks in the burden by the gas expansion. 

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  • Warlo, Mathis
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Sundin, Marcus
    Environment Department, Boliden AB, Boliden, Sweden.
    Jansson, Nils
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lawther, Anthony
    Exploration Department, Boliden AB, Garpenberg, Sweden.
    Controls on the industrial mineral potential of ore-proximal carbonate rocks, Garpenberg Zn-Pb-Ag-(Cu-Au) deposit, Bergslagen Sweden2025Inngår i: GFF, ISSN 1103-5897, E-ISSN 2000-0863Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The c. 1.89 Ga Garpenberg Zn-Pb-Ag-(Cu-Au) deposit is hosted by dolomite marble, skarn and felsic metavolcanic rocks. Extensive marble units host part of the mine infrastructure, including sections of bright-colored, chemically pure marble. Assessing the potential of carbonates as by-products to base metal mining is of interest for a sustainable and efficient use of resources and for securing a domestic supply of carbonates. This study characterizes marble units proximal to the Dammsjön and Lappberget ore bodies at Garpenberg based on their optical, chemical, mineralogical, and textural properties to delineate controls on their brightness, color, and purity. Methods employed include drill core logging, whole-rock lithogeochemistry, petrography, SEM-EDS, μXRF, spectrophotometric brightness measurements, and tests of AIR and magnetic separation. The marble units are divided into bright calcite marble (white, gray, and green varieties), dark calcite marble (salmon pink, spotted, brecciated, and ophicalcite varieties) and dolomite marble. Brightness and purity of the marbles are highly correlated, with Fe having a particularly detrimental effect on brightness, both via substitution in the dolomite and calcite lattices, but also via presence of accessory minerals that grind to dark powders. Ore-proximal dolomite marble shows a hydrothermal signature, with elevated base metals, Fe, S and Mn content, whereas impurities in calcite marble seem to mainly be of detrital origin, reflecting co-settled volcaniclastic and siliciclastic material in the limestone precursors. Mainly the bright calcite marble varieties are of potential industrial quality and are present in Garpenberg in significant volumes, but the technoeconomic feasibility of by-product valorization requires further analysis.

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  • Åström, Elisabeth
    et al.
    Department of Psychology, Umeå University, Umeå, Sweden.
    Eriksson Sörman, Daniel
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik, Hälsa, medicin och rehabilitering. Department of Psychology, Umeå University, Umeå, Sweden.
    Sörqvist, Patrik
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik, Hälsa, medicin och rehabilitering. Department of Building Engineering, Energy Systems, and Sustainability Science, University of Gävle, Gävle, Sweden.
    Ljungberg, Jessica K.
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik, Hälsa, medicin och rehabilitering.
    The Lifelong Learner’s Compass: Cultivating Attitudes With Self-Reflection, Openness, Curiosity and Motivation2025Inngår i: Adult Education Quarterly, ISSN 0741-7136, E-ISSN 1552-3047Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Lifelong learning can be indispensable for the adaptation to continuously evolving labor markets and societal demands. In the current study, we examined psychological factors, notably aspects of personality (personality traits in the five-factor model and trait curiosity), self-reflection and motivation in relation to attitudes to lifelong learning. A specific aim was to examine the relative importance of these factors in their contribution to attitudes to lifelong learning. The study was carried out by use of a digital survey and included 717 adults (Mage = 47.93) within working life. The results showed that self-reflection and trait curiosity were the strongest predictors of attitudes to lifelong learning but work intrinsic motivation and openness to experience (a personality trait in the five-factor model) also contributed with unique explanatory power, although to a lesser degree. The results can inform individualized accessibility strategies for lifelong learning.

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  • Acharki, Siham
    et al.
    Faculty of Sciences and Technologies of Tangier, Abdelmalek Essaadi University, 93000, Tetouan, Morocco; Center for Remote Sensing Applications (CRSA), Mohammed VI Polytechnic University (UM6P), 43150, Benguerir, Morocco.
    Raza, Ali
    School of Agricultural Engineering, Jiangsu University, Zhenjiang, 212013, People’s Republic of China.
    Vishwakarma, Dinesh Kumar
    Department of Irrigation and Drainage Engineering, G.B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, 263145, India.
    Amharref, Mina
    Faculty of Sciences and Technologies of Tangier, Abdelmalek Essaadi University, 93000, Tetouan, Morocco.
    Bernoussi, Abdes Samed
    Faculty of Sciences and Technologies of Tangier, Abdelmalek Essaadi University, 93000, Tetouan, Morocco.
    Singh, Sudhir Kumar
    K. Banerjee Centre of Atmospheric and Ocean Studies, University of Allahabad, Prayagraj, Uttar Pradesh, 211002, India.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dewidar, Ahmed Z.
    Prince Sultan Bin Abdulaziz International Prize for Water Chair, Prince Sultan Institute for Environmental, Water and Desert Research, King Saud University, P.O. Box 2454, Riyadh 11451, Saudi Arabia; Department of Agricultural Engineering, College of Food and Agriculture Sciences, King Saud University, Riyadh 11451, Saudi Arabia.
    Al-Othman, Ahmed A.
    Department of Agricultural Engineering, College of Food and Agriculture Sciences, King Saud University, Riyadh 11451, Saudi Arabia.
    Mattar, Mohamed A.
    Prince Sultan Bin Abdulaziz International Prize for Water Chair, Prince Sultan Institute for Environmental, Water and Desert Research, King Saud University, P.O. Box 2454, Riyadh 11451, Saudi Arabia; Department of Agricultural Engineering, College of Food and Agriculture Sciences, King Saud University, Riyadh 11451, Saudi Arabia; Agricultural Engineering Research Institute (AEnRI), Agricultural Research Centre, P.O. Box 256, Giza, Egypt.
    Comparative assessment of empirical and hybrid machine learning models for estimating daily reference evapotranspiration in sub-humid and semi-arid climates2025Inngår i: Scientific Reports, E-ISSN 2045-2322, Vol. 15, nr 1, artikkel-id 2542Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Improving the accuracy of reference evapotranspiration (RET) estimation is essential for effective water resource management, irrigation planning, and climate change assessments in agricultural systems. The FAO-56 Penman-Monteith (PM-FAO56) model, a widely endorsed approach for RET estimation, often encounters limitations due to the lack of complete meteorological data. This study evaluates the performance of eight empirical models and four machine learning (ML) models, along with their hybrid counterparts, in estimating daily RET within the Gharb and Loukkos irrigated perimeters in Morocco. The ML models examined include Random Forest (RF), M5 Pruned (M5P), eXtreme Gradient Boosting (XGBoost), and Light Gradient Boosting Machine (LightGBM), with hybrid combinations of RF-M5P, RF-XGBoost, RF-LightGBM, and XGBoost-LightGBM. Six input combinations were created, utilizing Tmax, Tmin, RHmean, Rs, and U2, with the PM-FAO56 model serving as the benchmark. Model performance was assessed using four statistical indicators: Kling-Gupta efficiency index (KGE), coefficient of determination (R2), mean squared error (RMSE), and relative root squared error (RRSE). Results indicate that the Valiantzas 2013 (VAL2013b) model outperformed other empirical models across all stations, achieving high KGE and R2 values (0.95–0.97) and low RMSE (0.32–0.35 mm/day) and RRSE (8.14–10.30%). The XGBoost-LightGBM and RF-LightGBM hybrid models exhibited the highest accuracy (average RMSE of 0.015–0.097 mm/day), underscoring the potential of hybrid ML models for RET estimation in subhumid and semi-arid regions, thereby enhancing water resource management and irrigation scheduling.

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  • Qvarforth, A.
    et al.
    Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden.
    Svensson, P. A.
    Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden.
    Lundgren, M.
    Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden.
    Rodushkin, Ilia
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Engström, Emma
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik. ALS Laboratory Group, ALS Scandinavia AB, Luleå, Sweden.
    Paulukat, C.
    ALS Laboratory Group, ALS Scandinavia AB, Luleå, Sweden.
    Hough, R. L.
    The James Hutton Institute, Craigiebuckler, Aberdeen, UK.
    Moreno-Jiménez, E.
    Department of Agricultural and Food Chemistry, Faculty of Sciences, Universidad Autónoma de Madrid, Madrid, Spain; Institute of Advanced Chemistry, Faculty of Sciences, Universidad Autónoma de Madrid, Madrid, Spain.
    Beesley, L.
    Department of Environmental Geosciences, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Czech Republic; School of Science, Engineering and Environment, Peel Building, University of Salford, Manchester, UK.
    Trakal, L.
    Department of Environmental Geosciences, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Czech Republic.
    Augustsson, A.
    Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden.
    Geochemical insights into plant uptake of Technology-critical elements: A case study on lettuce from European soils2025Inngår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 371, artikkel-id 144073Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    While vegetable uptake of traditional metal contaminants is a well-studied pathway to human exposure and risk, a paucity of information exists on the uptake of emerging metal contaminants. This study evaluated the uptake of the Technology-critical elements (TCEs) gallium (Ga), germanium (Ge), niobium (Nb), tantalum (Ta), thallium (Tl), and rare earth elements (REEs) into lettuce cultivated in 21 European urban soils. For comparison, the uptake of cadmium (Cd) was also analysed. First, the uptake was predicted by multiplying soil concentrations with previously established bioconcentration factors (BCFs). Subsequently, multiple regression models incorporating geochemical variables as predictors were used to determine whether prediction accuracy could be improved. A "3-predictor model" incorporated soil TCE concentration, pH, and organic matter (OM), and a "7-predictor model" added data on clay content and the soil concentrations of Fe, Al, and Mn as well. With the exception of Cd, Ge, and Tl, the BCF approach provided unsatisfactory predictions (R2 < 0.5), while the 7-predictor models yielded the best predictions, even when accounting for the greater number of predictors. While the most important predictors of uptake varied somewhat between the TCEs, the concentrations of TCEs in the soil generally explained the largest proportion of the variation. The least influential predictors in our dataset were [Mnsoil], [Fesoil], and soil OM. Incorporating geochemical data generally improved the predictions of uptake by lettuce, and these findings underscore the need for more detailed characterisations of the uptake potential of TCEs by food plants and subsequent consequences for human health.

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  • Moretti, Anna
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Hållfasthetslära. GKN Aerospace Sweden AB, Trollhättan, Sweden.
    Lundbäck, Andreas
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Hållfasthetslära.
    Lindgren, Lars-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Hållfasthetslära.
    Recrystallization and stress evolution in Alloy 7182025Inngår i: Journal of thermal stresses, ISSN 0149-5739, E-ISSN 1521-074XArtikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An extensive plasticity model base useful to predict stresses in thermo-mechanical processes where the microstructure changes has been established. The densities of mobile and immobile dislocations are the basic ingredients in the model. The motion of the former corresponds to plastic strain rate. The interaction between moving dislocations and various obstacles contributes to the material resistance. The focus is on the developed recrystallization model that is based on dislocation densities. The results show that recrystallization at high strain rates leads to a large number of nuclei that grow after the test. This means that most of the recrystallization occurs after the test

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  • Basnin, Nanziba
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Mahmud, Tanjim
    Department of Computer Science and Engineering, Rangamati Science and Technology University, Rangamati 4500, Bangladesh.
    Islam, Raihan Ul
    Department of Computer Science and Engineering, East West University, Dhaka 1212, Bangladesh.
    Andersson, Karl
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    An Evolutionary Federated Learning Approach to Diagnose Alzheimer’s Disease Under Uncertainty2025Inngår i: Diagnostics, ISSN 2075-4418, Vol. 15, nr 1, artikkel-id 80Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Alzheimer’s disease (AD) leads to severe cognitive impairment and functional decline in patients, and its exact cause remains unknown. Early diagnosis of AD is imperative to enable timely interventions that can slow the progression of the disease. This research tackles the complexity and uncertainty of AD by employing a multimodal approach that integrates medical imaging and demographic data. Methods: To scale this system to larger environments, such as hospital settings, and to ensure the sustainability, security, and privacy of sensitive data, this research employs both deep learning and federated learning frameworks. MRI images are pre-processed and fed into a convolutional neural network (CNN), which generates a prediction file. This prediction file is then combined with demographic data and distributed among clients for local training. Training is conducted both locally and globally using a belief rule base (BRB), which effectively integrates various data sources into a comprehensive diagnostic model. Results: The aggregated data values from local training are collected on a central server. Various aggregation methods are evaluated to assess the performance of the federated learning model, with results indicating that FedAvg outperforms other methods, achieving a global accuracy of 99.9%. Conclusions: The BRB effectively manages the uncertainty associated with AD data, providing a robust framework for integrating and analyzing diverse information. This research not only advances AD diagnostics by integrating multimodal data but also underscores the potential of federated learning for scalable, privacy-preserving healthcare solutions.

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  • Hällström, Lina P.B.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Öhlander, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Dissolved beryllium (< 1 kDa) mobilized as a major element in groundwater in legacy mine waste2025Inngår i: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 367, artikkel-id 125671Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Research regarding the geochemistry of beryllium (Be) in terrestrial environments is hindered by its high toxicity to humans and the low concentrations normally occurring in the environment. Although Be is considered an immobile element, extremely high dissolved concentrations have been detected in groundwater in the legacy Tailings Storage Facility (TSF) of Smaltjärnen, Sweden. Therefore, a detailed study was conducted to determine physiochemical parameters affecting the speciation of Be in the groundwater. Groundwater was sampled from 2016 to 2024 and filtered through 0.2 μm filters, whereas truly dissolved fraction (<1 kDa) samples were collected with dialysis membrane tubes in situ at groundwater wells. Secondary minerals on the tailings shore were studied by mineralogical methods and sequential extraction to trace the pathway whereby Be entered the downstream surface water. In part of the tailings, dissolved Be was detected in very high concentrations (average: 4.8 mg/L) in suboxic groundwater with pH from 6.0 to 6.4. Dialysis sampling in 2024 showed that more than 90% occurred as truly dissolved Be (<1 kDa). A significant correlation between Be and S was found, suggesting that sulfate complexes kept Be mobile in these pH conditions. Dissolved Be increased with decreased pH, and there is risk that the concentrations will increase further since sulfide oxidation with subsequent decrease in pH will continue for 100 of years in the TSF. In another part of the TSF, the pH was >6.4 and dissolved Be was below the detection limit, possibly due to formation of Al(OH)3 (>0.2 μm) together with F and Zn. Secondary minerals on the shore of the tailings functioned as a temporary chemical barrier, scavenging Be primarily by secondary gypsum when present and otherwise by Fe-(hydr)oxides.

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  • Weiland, Fredrik
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap. RISE Research Institutes of Sweden, Box 726, S-941 28, Piteå, Sweden.
    Mases, Mattias
    RISE Research Institutes of Sweden, Box 726, S-941 28, Piteå, Sweden.
    Jacobsson, Daniel
    Centre for Analysis and Synthesis, and NanoLund, Lund University, Box 124, S-2210 00, Lund, Sweden.
    Wahlqvist, David
    Centre for Analysis and Synthesis, and NanoLund, Lund University, Box 124, S-2210 00, Lund, Sweden.
    Ek, Martin
    Centre for Analysis and Synthesis, and NanoLund, Lund University, Box 124, S-2210 00, Lund, Sweden.
    Wiinikka, Henrik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap. RISE Research Institutes of Sweden, Box 726, S-941 28, Piteå, Sweden.
    Oxidation of carbon nanomaterials using a nanoparticulate iron oxide catalyst: Direct observations in an electron microscope2025Inngår i: Carbon, ISSN 0008-6223, E-ISSN 1873-3891, Vol. 234, artikkel-id 119896Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Understanding of carbon nanomaterials oxidation is useful in many different applications, e.g., for soot emission abatement, or in defect engineering aiming to improve material properties. In this work, the oxidative behavior of three substantially different qualities of carbon black, multiwall carbon-nanotubes, and few-layer graphene, was studied using a combination of macroscale quantification (using thermogravimetric analysis) and nanoscale imaging of their structural evolution (using environmental transmission electron microscopy, ETEM). The materials were investigated both with and without the addition of a nanoparticulate iron oxide catalyst. Catalyst addition clearly lowered the conversion temperature during oxidation. The ETEM revealed that the catalyst nanoparticles induced primary surface damages in the carbon nanostructure at relatively low temperatures. From there, oxidation could proceed more rapidly at recently exposed edge sites due to their higher propensity for oxidation. Thus, the enhanced oxidation was not solely linked to the interface between catalyst and carbon.

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  • Forsström, David
    et al.
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden.
    Badinlou, Farzaneh
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden; Medical Unit Medical Psychology, Women’s Health and Allied Health Professionals Theme, Karolinska University Hospital, Solna, Sweden.
    Johansson, Magnus
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden; Division Built Environment, System Transition, RISE Research Institutes of Sweden, Stockholm, Sweden.
    Ojala, Olivia
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden.
    Alaoui, Samir El
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden.
    Månsson, Kristoffer N. T.
    Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    Rozental, Alexander
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik, Hälsa, medicin och rehabilitering. Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden.
    Lundin, Johan
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden.
    Jangard, Simon
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden; Department of Clinical Neuroscience, Division of Psychology, Karolinska Institutet, Solna, Sweden.
    Shahnavaz, Shervin
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden.
    Sörman, Karolina
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden.
    Jayaram-Lindström, Nitya
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden.
    Lundgren, Tobias
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden.
    Jansson-Fröjmark, Markus
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden.
    Hedman-Lagerlöf, Maria
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden.
    Psychometric properties of the Swedish version of the Patient Health Questionnaire-9: an investigation using Rasch analysis and confirmatory factor analysis2025Inngår i: BMC Psychiatry, E-ISSN 1471-244X, Vol. 25, nr 1, artikkel-id 36Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Depression is one of the most common psychiatric conditions. Given its high prevalence and disease burden, accurate diagnostic procedures and valid instruments are warranted to identify those in need of treatment. The Patient Health Questionnaire-9 (PHQ-9) is one of the most widely used self-report measures of depression, and its validity and reliability has been evaluated in several languages. However, the Swedish translation has yet not been subject to psychometric evaluation, and no previous psychometric evaluation of the instrument have used both Rasch analysis and classic test theory. The aim of this study was to investigate validity and reliability of the PHQ-9 in a Swedish sample of individuals with self-reported current or past mental health problems using Rasch analysis and confirmatory factor analysis. A sample of 4958 participants was recruited from an online survey covering different aspects of covid-19 and mental health targeted towards individuals with mental health problems. Results showed that a one-factor solution fit the data after removing one item and that some items had a different response pattern for older respondents. Furthermore, after removing item 2 and merging the two middle response categories for item 9, the Swedish translation of PHQ-9 showed adequate psychometric properties. The findings suggests that the Swedish translation of PHQ-9 may need to be adapted in order to make adequate interpretations of an individual score and to differentiate between populations. Further tests of its validity and reliability in other Swedish samples are needed to fully understand the properties of the Swedish version of PHQ-9. 

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  • Nilsson, Dan A.
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Andersson, Anders G.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Larsson, I.A. Sofia
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Andersson, Robin
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Billstein, Mats
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik. Vattenfall, Research & Development Hydraulic Laboratory, 814 26 Älvkarleby, Sweden.
    Three-Dimensional Particle Tracking Velocimetry Investigation of Flow Dynamics Around Simplified Stones at Low Submergence: Implications for Instream Habitat2025Inngår i: Water, E-ISSN 2073-4441, Vol. 17, nr 2, artikkel-id 217Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Shallow waterways such as rapids, tributaries and smaller streams can have important ecological functions in both free-flowing and regulated rivers. As more intermittent renewable energy is introduced to the energy system to reduce CO2 emissions, the operational conditions of hydropower plants are changing. This implies various flow scenarios that can lead to more locations with shallow depths and larger variations in water levels and velocities, resulting in increased impact on the riverine ecosystem. Accurate predictions of these impacts require an understanding of the flow dynamics near large roughness elements such as boulders or trees in shallow river regions. This study uniquely investigates the effect of relative submergence, i.e., water depth relative to boulder size, on the flow field, turbulence, and potential fish habitats around idealized stone shapes (hemispheres) in shallow open channel flow using time-resolved 3D particle tracking velocimetry. The results indicate that varying relative submergence significantly affects recirculation zones, velocity and vorticity distribution, as well as turbulent kinetic energy. Notably, larger regions of lower velocity downstream of the roughness elements were generated at lower submergences, which might be favorable for fish energy conservation. Valuable insights into ecohydraulic engineering and habitat restoration in shallow waterways can be gained by understanding the fundamental flow mechanisms at low submergence for the flow around large roughness elements.

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  • Eneslätt, Malin
    et al.
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik, Omvårdnad och medicinsk teknik. Karolinska Institutet, Sweden.
    Jobe, Ingela
    University of Stavanger, Norway.
    Melander, Catharina
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik, Omvårdnad och medicinsk teknik.
    We are all mortals - Undergraduate nursing students’ reflections following a seminar focused on proactive end-of-life communication2024Inngår i: 8th Public Health Palliative Care International Conference: Building Bridges between Science and People, Sage Publications, 2024, s. 108-, artikkel-id 286Konferansepaper (Fagfellevurdert)
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  • Cao, Jie
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Wang, Chao
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Gonzalez-Libreros, Jaime
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Wang, Tongfang
    Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education, National Engineering Research Center for Prestressing Technology, School of Civil Engineering, Southeast University, Nanjing 211189, PR China.
    Tu, Yongming
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education, National Engineering Research Center for Prestressing Technology, School of Civil Engineering, Southeast University, Nanjing 211189, PR China.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Extended applications of molecular dynamics methods in multiscale studies of concrete composites: A review2025Inngår i: Case Studies in Construction Materials, E-ISSN 2214-5095, Vol. 22, artikkel-id e04153Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    This paper investigates the current landscape of multiscale studies in concrete composites incorporating molecular dynamics (MD) methods. Through a thorough literature analysis, it was determined that finite element, discrete element, homogenization, microphysical characterization, and machine learning methods are better suited for integration with MD in multiscale studies of concrete composites. The paper delves into MD's application characteristics and the selection of force fields in multiscale studies and provides a summary of the combined applications between MD and various methods. Challenges identified include the optimization of MD simulations and the appropriate selection of combined methods. The conclusions underscore the growing recognition of MD's significance, advocating for rational multi-method integration in multiscale approaches to effectively advance research on concrete composites.

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  • Krigsman, Olivia
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Samhällsvetenskap.
    Stage, Jesper
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Samhällsvetenskap.
    Möjligheter att inventera fly-in fly-out arbetskraft inom Norrbottens kommuner – Förstudie2024Rapport (Annet (populærvitenskap, debatt, mm))
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  • Berglund, Leif
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Människa och teknik.
    Johansson, Jan
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Människa och teknik.
    Johansson, Maria
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Människa och teknik.
    Nygren, Magnus
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Människa och teknik.
    Stenberg, Magnus
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Människa och teknik.
    Chefen som anställd: En studie om de produktionsnära byggchefernas organisatoriska och sociala arbetsmiljö: Delrapport 2: Produktionsprocessen och platschefens arbetssituation2024Rapport (Annet vitenskapelig)
    Abstract [sv]

    Syftet med denna delrapport är att dels beskriva byggprocessens mest centrala delar, dels beskriva platschefernas arbetssituation i bygg- och anläggningsindustrin.

    Den första delen av delrapporten redovisar byggprocessens generella delar utifrån den beskrivning som görs av denna i Hansson, m.fl. bok ”Byggledning Produktion” (2021). Den andra delen där två platschefers arbetssituation redovisas bygger på två intervjuer med en platschef från ett byggprojekt och en platschef från ett anläggningsprojekt. Resultaten visar att platscheferna uppvisar ett stort intresse för sina respektive arbeten men att det samtidigt ställs höga krav på dem som individer i fråga om arbetsprestation och till viss del arbetstid och tillgänglighet.

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