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  • Taranova, Anastasiia
    et al.
    Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, 30172, Venice, Italy View author publications.
    Akbar, Kamran
    Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, 30172, Venice, Italy.
    Yusupov, Khabib
    Department of Physics, Chemistry and Biology (IFM), Linköping University, 581 83, Linköping, Sweden.
    You, Shujie
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Polewczyk, Vincent
    Istituto Officina dei Materiali (IOM) - CNR, Laboratorio TASC, Area Science Park, S.S. 14 Km 163.5, Trieste, I-34149, Italy.
    Mauri, Silvia
    Istituto Officina dei Materiali (IOM) - CNR, Laboratorio TASC, Area Science Park, S.S. 14 Km 163.5, Trieste, I-34149, Italy; Dipartimento di Fisica, University of Trieste, via A. Valerio 2, 34127, Trieste, Italy.
    Balliana, Eleonora
    Department of Environmental Sciences, Informatics and Statistics, Ca’ Foscari University of Venice, Scientific Campus Via Torino 155/b, 30173, Venice, Italy.
    Rosen, Johanna
    Department of Physics, Chemistry and Biology (IFM), Linköping University, 581 83, Linköping, Sweden.
    Moras, Paolo
    Istituto di Struttura della Materia (ISM) - CNR, S.S. 14 Km 163.5, Trieste, I-34149, Italy.
    Gradone, Alessandro
    Istituto per la Microelettronica ed i Microsistemi (IMM) – CNR Sede di Bologna, via Gobetti 101, 40129, Bologna, Italy.
    Morandi, Vittorio
    Istituto per la Microelettronica ed i Microsistemi (IMM) – CNR Sede di Bologna, via Gobetti 101, 40129, Bologna, Italy.
    Moretti, Elisa
    Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, 30172, Venice, Italy.
    Vomiero, Alberto
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, 30172, Venice, Italy.
    Unraveling the optoelectronic properties of CoSbx intrinsic selective solar absorber towards high-temperature surfaces2023In: Nature Communications, E-ISSN 2041-1723, Vol. 14, no 1, article id 7280Article in journal (Refereed)
    Abstract [en]

    The combination of the ability to absorb most of the solar radiation and simultaneously suppress infrared re-radiation allows selective solar absorbers (SSAs) to maximize solar energy to heat conversion, which is critical to several advanced applications. The intrinsic spectral selective materials are rare in nature and only a few demonstrated complete solar absorption. Typically, intrinsic materials exhibit high performances when integrated into complex multilayered solar absorber systems due to their limited spectral selectivity and solar absorption. In this study, we propose CoSbx (2 < x < 3) as a new exceptionally efficient SSA. Here we demonstrate that the low bandgap nature of CoSbx endows broadband solar absorption (0.96) over the solar spectral range and simultaneous low emissivity (0.18) in the mid-infrared region, resulting in a remarkable intrinsic spectral solar selectivity of 5.3. Under 1 sun illumination, the heat concentrates on the surface of the CoSbx thin film, and an impressive temperature of 101.7 °C is reached, demonstrating the highest value among reported intrinsic SSAs. Furthermore, the CoSbx was tested for solar water evaporation achieving an evaporation rate of 1.4 kg m−2 h−1. This study could expand the use of narrow bandgap semiconductors as efficient intrinsic SSAs with high surface temperatures in solar applications.

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  • Malmström, Johanna
    Luleå University of Technology, Department of Health, Learning and Technology, Education, Language, and Teaching.
    Feministiska perspektiv i klassrummet: – en insyn i svensklärares arbete med skolans värdegrund2023Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Jämställdhet är en del av skolans värdegrund. Feminism, ett svårtolkat begrepp kan tyckas, har nära kopplingar till jämställdhet, särskillt ur ett historiskt perspektiv. Det historiska och nutida perspektivet på feminism och jämställdhet utgör en väv sammanflätad av litteratur, språk och samhälleliga tankar och idéer. Syftet med den här studien var därför att synliggöra svensklärares metoder för att arbeta med feministiska perspektiv i undervisningen, eftersom att svenskämnet är ett ämne som sägs vila på två ben: språk och litteratur. Forskningsfrågorna som ämnades besvaras var 1. hur arbetar svensklärare med att synliggöra feministiska perspektiv i undervisningen i relation till ämnets innehåll? och 2. vilka metoder använder svensklärare för att tackla eventuell problematik som kan uppkomma när man undervisar känsliga ämnen så som feminism eller jämställdhet?

    Metoden som användes för att få svar på frågorna var kvaletativa semistrukturerade intervjuer. Fyra lärare som arbetar på olika skolor i norbotten intervjuades. Lärarna var i olika åldrar och de intervjuade bestod av två män och två kvinnor. Studien har en fenomenologisk ansats. 

    Resultatet från studien visar att samtliga lärare arbetar med feministiska perspektiv i all sin undervisning i olika grader. Högst genomslag får feministiska perspektiv eller skolans jämställdhetsarbete i relation till litteratur, men även i andra delar av undervsiningen synliggörs perspektiven. 

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  • Shaner, Sebastian
    et al.
    Department of Microsystems Engineering, University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg im Breisgau, Germany; BrainLinks-BrainTools Center, University of Freiburg, Georges-Köhler-Allee 201, 79110 Freiburg im Breisgau, Germany.
    Lu, Han
    BrainLinks-BrainTools Center, University of Freiburg, Georges-Köhler-Allee 201, 79110 Freiburg im Breisgau, Germany; Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Albertstraße 17, 79104 Freiburg im Breisgau, Germany.
    Lenz, Maximilian
    Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Albertstraße 17, 79104 Freiburg im Breisgau, Germany; Hannover Medical School, Institute of Neuroanatomy and Cell Biology, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
    Garg, Shreyash
    Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Albertstraße 17, 79104 Freiburg im Breisgau, Germany; MSc Neuroscience Program, Faculty of Biology, University of Freiburg, Schänzlestraße 1, 79104 Freiburg im Breisgau, Germany.
    Vlachos, Andreas
    BrainLinks-BrainTools Center, University of Freiburg, Georges-Köhler-Allee 201, 79110 Freiburg im Breisgau, Germany; Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Albertstraße 17, 79104 Freiburg im Breisgau, Germany; Center for Basics in Neuromodulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, 79104 Freiburg im Breisgau, Germany.
    Asplund, Maria
    Luleå University of Technology, Department of Health, Learning and Technology, Nursing and Medical Technology. Department of Microsystems Engineering, University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg im Breisgau, Germany; BrainLinks-BrainTools Center, University of Freiburg, Georges-Köhler-Allee 201, 79110 Freiburg im Breisgau, Germany; Department of Microtechnology and Nanoscience, Chalmers University of Technology, Chalmersplatsen 4, 41258 Gothenburg, Sweden; Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, Albertstraße 19, 79104 Freiburg im Breisgau, Germany.
    Brain stimulation-on-a-chip: a neuromodulation platform for brain slices2023In: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189, Vol. 23, no 23, p. 4967-4985Article in journal (Refereed)
    Abstract [en]

    Electrical stimulation of ex vivo brain tissue slices has been a method used to understand mechanisms imparted by transcranial direct current stimulation (tDCS), but there are significant direct current electric field (dcEF) dosage and electrochemical by-product concerns in conventional experimental setups that may impact translational findings. Therefore, we developed an on-chip platform with fluidic, electrochemical, and magnetically-induced spatial control. Fluidically, the chamber geometrically confines precise dcEF delivery to the enclosed brain slice and allows for tissue recovery in order to monitor post-stimulation effects. Electrochemically, conducting hydrogel electrodes mitigate stimulation-induced faradaic reactions typical of commonly-used metal electrodes. Magnetically, we applied ferromagnetic substrates beneath the tissue and used an external permanent magnet to enable in situ rotational control in relation to the dcEF. By combining the microfluidic chamber with live-cell calcium imaging and electrophysiological recordings, we showcased the potential to study the acute and lasting effects of dcEFs with the potential of providing multi-session stimulation. This on-chip bioelectronic platform presents a modernized yet simple solution to electrically stimulate explanted tissue by offering more environmental control to users, which unlocks new opportunities to conduct thorough brain stimulation mechanistic investigations.

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  • Štumpf, Martin
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab. Lerch Laboratory of EM Research, Department of Radio Electronics, FEEC, Brno University of Technology, Technická 3082/12, 616 00 Brno, The Czech Republic.
    Antonini, Giulio
    UAq EMC Laboratory, Dept. of Industrial and Information Engineering and Economics, University of L'Aquila, 671 00 L'Aquila, Italy.
    Ekman, Jonas
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Pulsed Electromagnetic Excitation of a Thin Wire – an Approximate Numerical Model Based on the Cagniard-DeHoop Method of Moments2023In: IEEE Antennas and Wireless Propagation Letters, ISSN 1536-1225, E-ISSN 1548-5757Article in journal (Refereed)
    Abstract [en]

    An approximate computational model of an electromagnetic (EM) pulse excited thin-wire antenna is developed. The presented solution methodology is based on the Cagniard-deHoop method of moments (CdH-MoM) and Hallén's approximation of the thin-wire model. It is shown that the proposed time-domain (TD) solution leads to an inversion-free, efficient updating procedure that mitigates the marching-on-in-time accumulation error. An illustrative numerical example demonstrates the validity of the proposed model.

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  • Taneez, Mehwish
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Lundy, Lian
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Impacts of stormwater pipe materials and pipe repairs on stormwater quality: a review2023In: Environmental Science and Pollution Research, ISSN 0944-1344, E-ISSN 1614-7499Article in journal (Refereed)
    Abstract [en]

    The water quality implications of transferring stormwater through pipes composed of concrete (new and used), polyvinyl chloride (PVC), galvanized corrugated steel (GCS), high-density polyethylene (HDPE), and pipes subjected to cured in place pipe (CIPP) and spray in place pipe (SIPP) trenchless repair technologies on stormwater quality are reviewed. Studies involve either the use of flowing water or an immersion experimental design, with data showing contact with pipe materials can affect stormwater quality parameters including pH, electrical conductivity (EC), and concentrations of minerals, metals, and organic constituents, e.g. styrene. ‘In-transport’ changes in pH (1–3 units), EC (2–3-fold), bicarbonate (3–44-fold), and calcium (2–17-fold) in stormwaters were reported following exposure to concrete pipes. Differences between the use of synthetic and field-collected stormwater were identified, e.g. turbidity levels in field-collected stormwater reduced on passage through all pipe types, compared to synthetic water where levels of turbidity on exposure to concrete and cement-based SIPP increased slightly. Transfer through PVC and HDPE pipes had minimal effects on physicochemical parameters, whereas exposure to galvanized corrugated steel pipes led to increases in EC, Zn, and Pb. Though limited data was available, the use of CIPP repairs and associated waste condensate generated during thermal curing and/or incomplete curing of resins was identified to release organic contaminants of concerns (e.g. styrene, vinylic monomers, dibutyl phthalate (DBP), diethyl phthalate (DEP), and benzaldehyde). The implications of findings for both future research and stakeholders with responsibility for reducing diffuse pollution loads to receiving waters are considered.

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  • Talekar, Ravikiran
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Insider Threat For Service Account in Google Cloud Platform2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As most software industry is migrating from traditional servers and depending more on Cloud-based services, we are encountering new problems hitherto unknown to us. Due to the variousadvantages offered by Cloud services and the numerous problems whose solutions are providedby Cloud technologies, cloud-based services have become very popular. Organizations of allsizes widely use them to meet their day-to-day technology needs. Cloud infrastructure mainlyconsists of Cloud resources and services, which are accessed through user and service accounts.This thesis considers the challenge of securing service accounts of cloud providers by serviceaccount keys. In the realm of cloud security, a central challenge revolves around the effectiveprotection of service account keys to thwart unauthorized access and the potential for databreaches, all while ensuring that legitimate operations maintain the necessary access. Eachservice account is intricately linked to a set of credentials, comprising both private and publickeys used for interactions with external APIs. These credentials play a critical role inauthenticating the service account and granting it authorization to access resources withinGoogle Cloud Platform (GCP). Notably, when service account keys are not downloaded, theprivate key remains confined within the GCP environment, limiting service interactions.Conversely, the act of downloading the private key increases the risk of exploitation, as itrepresents the most sensitive component of the service account credentials. Without access tothe private key, the authentication of the service account and subsequent access to GCPresources becomes unattainable.To address the holistic challenges in this thesis, it's crucial to emphasize the importance ofsecuring service account keys and limiting access to authorized users. This led to the proposalof a key rotation process to achieve our research objectives. The approach taken in this studyinvolves both qualitative and quantitative methods. This includes a thorough literature reviewand interviews with cloud professionals, allowing us to gain insights into the threats throughcontent analysis and a SWOT-based assessment. This method is aimed at mitigating the risk ofservice account key exploitation.

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  • Björnsson, Nina
    Luleå University of Technology, Department of Social Sciences, Technology and Arts.
    How does brands' participation in an accidental controversy affect their reputation?: An application of the situational crisis communication theory to firestorms2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study aims to investigate the strategies used by brands to recover from firestorms following controversies in the age of social media. The focus is on understanding the brand-customer relationship aspect of firestorms and the importance of monitoring and comprehending them to minimize their impact. The study applies the SCCT to analyze two specific firestorms and their effects on brand reputation.  The research questions focus on the initial crisis responsibility attached to the firestorm, the history the brand have with crisis and previous reputation. The study employs an exploratory qualitative research approach using a case study design. Data collection involves observing brands' social media and other communication channels to identify firestorm patterns and brand responses. Judgment sampling is used for sample selection, guided by relevant variables from the literature. Thematic analysis is employed to analyze qualitative data, with the SCCT guiding the analysis. Overall, this study contributes to understanding firestorms, trust recovery, and crisis communication in the digital age. The findings will shed light on effective strategies for managing and rebuilding brand reputation following firestorms. 

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  • Ali, Salamat
    et al.
    School of Materials and Energy, Lanzhou University, Lanzhou 730000, China.
    Ahmad, Awais
    Department of Chemistry, The University of Lahore, Lahore, 54590, Pakistan; Departamento de Química Orgánica, Universidad de Córdoba, Campus Universitario de Rabanales, Edificio Marie Curie (C3), E-14014 Córdoba, Spain.
    Hussain, Iftikhar
    Department of Mechanical Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong.
    Shah, Syed Shoaib Ahmad
    Department of Chemistry, School of Natural Sciences, National University of Sciences and Technology, Islamabad 44000, Pakistan.
    Ali, Shafqat
    Department of Physics, Shah Abdul Latif University Khairpur, Khairpur, Sindh, 66202, Pakistan.
    Ali, Asad
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Javed, Muhammad Sufyan
    Department of Chemistry, The University of Lahore, Lahore, 54590, Pakistan; School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China.
    Experimental and Theoretical Aspects of MXenes-Based Energy Storage and Energy Conversion Devices2023In: Journal of Chemistry and Environment, E-ISSN 2959-0132, Vol. 2, no 2, p. 54-81Article, review/survey (Refereed)
    Abstract [en]

    Transition metal carbides, nitrides, and carbonitrides (MXenes) have become an appealing framework for developing various energy applications. MXenes with van der Waals (vdW) interactions are facile, highly efficient, affordable, and self-assembled features that improve energy density. MXenes exhibit large surface area, high electric conductivity, and excellent electrochemical characteristics for various energy applications. This review summarizes and emphasizes the current developments in MXene with improved performance for energy storage or conversion devices, including supercapacitors (SCs), various types of rechargeable batteries (RBs), solar cells, and fuel cells. We discuss the crystal structures of MXenes properties of MXenes and briefly discuss them for different types of energy applications. Finally, the critical outlook and perspective for the MXene progress for applications in energy applications are also described.

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  • Engberg, Andrea
    et al.
    Luleå University of Technology, Department of Health, Learning and Technology.
    Rönnbäck, Petra
    Luleå University of Technology, Department of Health, Learning and Technology.
    Konsekvenser av att utsättas för hot och våld på akutmottagningen: Sjuksköterskors erfarenheter2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: På akutmottagningar utsätts sjuksköterskan dagligen för hot och våld på grund av den osäkra och föränderliga arbetsmiljön. Hot och våld påverkar sjuksköterskans fysiska och psykiska hälsa samt har konsekvenser för patienter, anhöriga, organisationen och det privata livet för sjuksköterskan. Syfte: Att studera sjuksköterskans erfarenheter av hot och våld på akutmottagning och dess konsekvenser. Metod: Analys med kvalitativ manifest och induktiv ansats.

    Analysen resulterade i fyra slutgiltiga kategorier: fysiska och psykiska konsekvenser för den utsatta sjuksköterskan, hot och våld kan bidra till brister i omvårdanden, hot och våld kan bidra till att sjuksköterskan vill lämna yrket och sjuksköterskans erfarenheter av hot och våld och dess påverkan på privatlivet. Resultat: Hot och våld på akutmottagning ledde till att sjuksköterskan upplevde fysiska och psykiska konsekvenser av våldet som vidare speglade viljan att lämna yrket, påverkan på relationer och omvårdnaden gentemot patient och anhörig. Slutsats: Sjuksköterskan bör få bättre stöd och hjälp för hantering av hot och våld på akutmottagning för att minska individuella konsekvenser och upprätthålla patientsäkerheten.

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  • Hänsel, Andreas
    et al.
    Saxon University of Cooperative Education, Glauchau, Germany; University for Sustainable Development, Eberswalde, Germany.
    Tröger, Johannes
    Institute for Machine Tools, Universität Stuttgart, Stuttgart, Germany.
    Rößler, Martin
    Saxon University of Cooperative Education, Academy of Studies Dresden, Dresden, Germany.
    Brachhold, Nora
    Institute for Ceramics, Fire Resistant and Composite Materials, TU Bergakademie Freiberg, Freiberg, Germany.
    Niemz, Peter
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering. Institute for Construction Materials, ETH Zürich, Zürich, Switzerland.
    Influence of surface treatment on the bonding quality of wood for load-bearing purposes2023In: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280Article in journal (Refereed)
    Abstract [en]

    This study investigates the influence of different machining processes on the tensile shear strength of glued lumber, focusing on optimizing the tool geometry of face milling. The data obtained were analyzed using statistical methods. The roughness of the surface produced by the machining process and the damage to the microstructure under the cutting edge are identified as important factors influencing the quality of the bond. The results show that the optimized process (low roughness and microstructure damage) leads to more effective gluing.

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  • Rönner, Johannes Samuel Erland
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Contribution to the Understanding of the Effects of Propagation through the Ionosphere of P-band SAR Data2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The BIOMASS mission from the European Space Agency (ESA) is designed to measurebiomass and carbon content in Earth’s forests. To account for phase changes caused byionospheric variations, a map-drift autofocus algorithm is developed, which utilises a phasescreen of the ionosphere to eliminate phase errors in the signal. In this development, a filteris employed to integrate and remove noise from the second-order derivative of the ionosphericphase screen. This thesis aims to analyse methods to implement this filter andcompare their efficiency.

    Two filters are constructed using two methods, a Least Mean Square (LMS) filter and aWiener filter. Further emphasis is placed on the Wiener filter, and the most optimal way tocalculate it is explored in detail. The aim is to produce a filter that can integrate, lower theimpact of noise as much as possible and be computationally efficient. An implementationwas made in Python using simulated data of an ionosphere.

    The conclusion is that the Wiener filter can yield improved results if a precise estimation ofthe autocorrelation function of the ionospheric phase screen can be determined, and thatlinear regression models might be a method to do so. There is also consideration taken tothe noise of the data, it is compensated for by utilising multiple data sources. Additionally,to enhance computational efficiency, a comparison of different solving methods for the linearsystem of equations that is the filter where made, showing a LU-decomposition method tobe efficient.

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  • Possidente, Luca
    et al.
    University of Trento, Department of Civil, Environmental and Mechanical Engineering, Via Mesiano 77, 38123, Trento, Italy.
    Tondini, Nicola
    University of Trento, Department of Civil, Environmental and Mechanical Engineering, Via Mesiano 77, 38123, Trento, Italy.
    Wickström, Ulf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Derivation of a new temperature calculation formulation for heavily fire insulated steel cross-sections2023In: Fire safety journal, ISSN 0379-7112, E-ISSN 1873-7226, Vol. 141, article id 103991Article in journal (Refereed)
    Abstract [en]

    Equations are given in the Eurocode standard EN 1993-1-2 on the estimation of temperature in insulated steel cross sections when assuming uniform steel section temperature, sometimes called a lumped heat capacity assumption. When deriving these equations the temperature of the exposed insulation surface is assumed equal the surrounding fire gas temperature. That is a simplification that may provide inaccurate results for heavily insulated steel sections, when the heat capacity of the insulation is considerably higher than that of the steel section. Therefore, a new lumped mass formulation suited for heavily insulated steel sections is proposed in this paper. It accounts for the heat transfer resistance between the fire and the insulation surface as well as for the heat capacity of the insulation. The accuracy of the predictions made with the proposed new formulation are compared with results of accurate 1-D finite element numerical analyses considering insulation materials with several combinations of thermal properties and thicknesses. Analyses with the proposed formulation is shown to yield accurate and generally on the safe side estimations of steel temperature in comparison to the finite element (FE) calculations. The new formulation is applicable to lightly as well as heavily insulated steel sections.

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  • Knutsson, Ebba
    Luleå University of Technology, Department of Social Sciences, Technology and Arts.
    Sustainable supply logistics and inventory management: A case study at Axelent AB2023Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study is to give an insight to operation and managerial possibilities anddifficulties of sustainable inventory management. The objective is to give a general picture ofwhat is available in terms of economic models as well as the implications from the currentsituation and eventual changes. The study uses an abductive approach with both qualitativeand quantitative data. Quantitative data is composed of current available measurement at thecase company, Axelent AB. While the qualitative is composed of interviews to establish theoperational framework at the case company.The study found that both the common Economic Lot-Scheduling and Economic OrderQuantity models have been successfully proven to be adaptable to include emission. Tomeasure emission's, the GHG Protocol is found to be useful and is recommended. Thoughmonetisation of emission’s are not consecutively required by the models, it is recommendedwith well selected prices. There is a need to establish the effects of a change in operations inorder to avoid negative effects on the everyday operations. The current way of operationwould most likely be changed if emission’s would be introducing into the inventorymanagement models.The study only included the supply where the company was the order trigger, therebyexcluding vendor-controlled inventory. The warehouse that was studied is in a shared buildingwith production. There were two components taken as examples for calculations.

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  • Jansson, Jenny
    Luleå University of Technology, Department of Health, Learning and Technology.
    Föräldrars upplevelser av att leva med ett barn som har Attention Deficit/Hyperactivity Disorder (ADHD): En litteraturstudie2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: Attention deficit/hyperactivity disorder (ADHD) hos barn är en av världens vanligaste neuropsykiatriska funktionsnedsättningar (NPF). Många människor har förutfattade meningar angående vad ADHD är, men att få lära sig och förstå hur det är att vara förälder till ett barn med ADHD och förstå vad dessa föräldrar går igenom varje dag, finns det inte tillräckligt mycket forskning om. Syfte: Att beskriva föräldrarnas upplevelse av att vara förälder till ett barn med ADHD. Metod: En litteraturstudie med kvalitativ design. För att få fram det kvalitativa materialet till studien användes tre databaser, PubMed, Cinahl och PsychInfo. En litteraturstudie med en kvalitativ innehållsanalys med induktiv ansats valdes för att kunna fördjupa sig i upplevelsen från ett inifrånperspektiv från föräldrar till barn med ADHD och deras vardag. Under innehållsanalysen användes ett manifest förhållningssätt för att analysera de utvalda artiklarna innehåll. Innehållsanalysen utfördes genom att de utvalda artiklarna lästes igenom och sedan extraherades textenheter, som är meningar, stycken eller citat som har relevans för det utvalda syftet. Efter kondensering och kategorisering av textenheter resulterade i fyra kategorier. Resultat: De fyra kategorierna som framkom i analysen var; Att hantera och uppleva stress i vardagslivet, Att känna press och krav från skolan, Att känna brist på stöd och resurser och Att bli socialt isolerad och stigmatiserad. I helhet kunde de ses i denna litteraturstudie att den generella upplevelsen av att vara förälder till ett barn med ADHD var den konstanta stressen. Stressen över deras framtid, stress för att de inte ska klara av skolan, stress över att de inte kommer ha några vänner och stressen över att inte veta när nästa utbrott kommer ske. Det som även kunde ses var att föräldrarna inte bara blev påverkade av barnets sjukdom, men även att syskonen påverkades. Slutsats: Att leva med ett barn som har ADHD resulterar i stor stress hos föräldrarna. Barnets beteende påverkar familjen i och utanför hemmet, samt hur skola och samhället uppfattar dem som familj och som föräldrar. Nyckelord: ADHD, Attention deficit/hyperactivity disorder, parents, lived experience, nursing, stress.

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  • Strömberg, Natalie
    et al.
    Luleå University of Technology, Department of Health, Learning and Technology.
    Strömberg, Wilma
    Luleå University of Technology, Department of Health, Learning and Technology.
    Unga vuxnas upplevelse av att leva med diabetes typ 1: En litteraturöversikt2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: Diabetes typ 1 är en kronisk autoimmun sjukdom som orsakar att personen behöver regelbunden behandling. Det påverkar deras vardag och kan orsaka både kort- och långsiktiga komplikationer. Livet som ung vuxen kan vara utmanande och att samtidigt leva med kronisk sjukdom kan skapa svårigheter, i en redan komplex period i livet. Utökad kunskap om detta är därför viktigt för hälso- och sjukvårdspersonal. Syfte: Att beskriva unga vuxnas upplevelser av att leva med diabetes typ 1. Metod: Litteraturstudien baseras på kvalitativa studier och analyserades med kvalitativ manifest innehållsanalys med induktiv ansats. Resultat: Data resulterade i 7 slutkategorier: Stöttande omgivning är betydelsefullt och ger trygghet, Svårighet att hitta balans mellan diabeteshanteringen och livet, Det ökade ansvaret är betungande men leder även till personlig utveckling, Önskan att passa in och inte stigmatiseras, Behov av frihet och kontroll kan påverka diabeteshanteringen, Att det finns barriärer inom hälso- och sjukvården, Rädsla över komplikationer och graviditet. Slutsatser: Upplevelser av att leva med diabetes typ 1 varierade mellan de unga vuxna. Det fanns en gemensam önskan över ökad kunskap och förståelse i samhället och hos hälso- och sjukvårdspersonal för att de ska kunna tillgodose individuella behov och en personcentrerad vård.

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  • Heiaas, Denzel
    et al.
    Luleå University of Technology, Department of Social Sciences, Technology and Arts.
    Olofsson, Isac
    Luleå University of Technology, Department of Social Sciences, Technology and Arts.
    Ledarskap över generationsgränser: En studie om att leda olika generationer2023Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund - Generationer är grupper av människor födda under specifika tidsperioder medgemensamma erfarenheter och värderingar. Ledare behöver vara medvetna omgenerationsskillnader och vara flexibla i sitt ledarskap för att främja produktivitet ochmotivation på arbetsplatsen. Ledarskapets utveckling har gått från auktoritära till merinkluderande och deltagande stilar. Ledarskap innefattar egenskaper som kommunikation,beslutsfattande, empati och konflikthantering, och kan utövas av personer på olika nivåer i enorganisation. Ledarskap är en dynamisk process som kräver anpassning till olika situationeroch människor.

    Syfte - Studiens syfte är att ta reda på och öka förståelsen kring hur ledare agerar för att ledagenerationsöverskridande grupper av medarbetare.

    Metod - Studien är gjord med en kvalitativ forskningsmetod i form av semistruktureradedjupintervjuer. Studien baseras på tidigare forskning och 12 respondenter frånsemistrukturerade djupintervjuer. En tematisk analys har använts för att skriva analysen.

    Empiri - Studiens empiri bygger på tre områden, ledarskap, motivation och anpassning tillgenerationer. Empirin synliggör att ledarskap och motivationsmetoder påverkargenerationerna olika, vilket reflekterar att ett anpassat ledarskap för generationer kan geväntat bättre resultat i form av motivation och engagemang hos medarbetare. Vidarepresenterar studiens empiri svårigheter att anpassa sitt ledarskap strikt eftergenerationstillhörighet när det är generationsöverskridande grupper, där agerar ledare frånolika generationer annorlunda.

    Begränsningar - Antalet respondenter i studien var 12 ledare vilket utgjorde ett större behovav generalisering i studien. Även tidigare litteratur om generation Z på arbetsmarknaden varbristfällig vilket påverkade vår förmåga att analysera.

    Originalitet/värde - Studien bidrar till ökad förståelse för hur ledare från olika generationerkan hantera och leda generationsöverskridande grupper. Ledare bör vara medvetna omgenerationsskillnader, vara flexibla i sitt ledarskap och kunna identifiera närgenerationstillhörighet inte överensstämmer med individuell identitet, vilket kan främjaproduktivitet, motivation och harmoni på arbetsplatsen.

    Begrepp - Generation X; Generation Y; Generation Z; Ledarskap; Motivation; Generationellaskillnader; Generationsöverskridande grupper; Transaktionellt ledarskap; Utvecklandeledarskap; Visionärt ledarskap.

    Uppsatstyp - Magisteruppsats

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  • Wasiq, Muhammad
    Luleå University of Technology, Department of Social Sciences, Technology and Arts.
    The Role of Digital Social Media Marketing in Internationalization of Swedish Apparel SMEs2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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  • Haefner, Naomi
    et al.
    Global Center for Entrepreneurship & Innovation, University of St. Gallen, Switzerland; Institute of Technology Management, University of St. Gallen, Switzerland.
    Parida, Vinit
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Business Administration and Industrial Engineering. Department of Management/USN Business School, University of Vaasa/University of South-Eastern Norway, Finland/Norway.
    Gassmann, Oliver
    Global Center for Entrepreneurship & Innovation, University of St. Gallen, Switzerland; Institute of Technology Management, University of St. Gallen, Switzerland.
    Wincent, Joakim
    Global Center for Entrepreneurship & Innovation, University of St. Gallen, Switzerland; Entrepreneurship and Innovation, Hanken School of Economics, Finland.
    Implementing and scaling artificial intelligence: A review, framework, and research agenda2023In: Technological forecasting & social change, ISSN 0040-1625, E-ISSN 1873-5509, Vol. 197, article id 122878Article, review/survey (Refereed)
    Abstract [en]

    Artificial intelligence (AI) will have a substantial impact on firms in virtually all industries. Without guidance on how to implement and scale AI, companies will be outcompeted by the next generation of highly innovative and competitive companies that manage to incorporate AI into their operations. Research shows that competition is fierce and that there is a lack of frameworks to implement and scale AI successfully. This study begins to address this gap by providing a systematic review and analysis of different approaches by companies to using AI in their organizations. Based on these experiences, we identify key components of implementing and scaling AI in organizations and propose phases of implementing and scaling AI in firms.

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  • Witecki, Kajetan
    et al.
    KGHM Cuprum Ltd, Res & Dev Ctr, Wroclaw, Poland; Wroclaw Univ Sci & Technol, Wroclaw, Poland.
    Szkurat, Monika
    KGHM Cuprum Ltd, Res & Dev Ctr, Wroclaw, Poland.
    Hruzova, Katerina
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Organosolv lignin particles as an ecological reagent in the Kupfershiefer copper ore flotation2023In: Physicochemical Problems of Mineral Processing, ISSN 1643-1049, Vol. 59, no 6, article id 174363Article in journal (Refereed)
    Abstract [en]

    Mineral separation relies heavily on the process of flotation. This study explored the feasibility of using organosolv lignin nanoparticles and microparticles (OLP) as a greener alternative to xanthates in the flotation process for mineral separation. Xanthates are widely used but pose environmental and health risks. The efficiency of OLP as collectors was compared to collectorless flotation, resulting in approximately 50% copper recovery, indicating that OLP may not be a suitable replacement for xanthates. Further tests were conducted using a mixture of xanthates and OLP (birch nano and spruce micro) with varying substitution levels (20%, 30%, and 40%). The results demonstrated that increasing the dosage of OLP led to a decrease in flotation efficiency for copper. TOC analysis of the products revealed that high dosages (160 g/t) of birch nano and spruce micro as sole collectors showed beneficiation and selective recovery against copper. While OLPs did not prove effective as collectors, the study highlights their potential as substitutes for maltodextrin in selective flotation of the final concentrate. Two out of four tested OLPs were recommended for pilot scale testing.

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  • Kareem, Baydaa Abdul
    et al.
    Univ Maysan, Dept Civil Engn, Maysan 57000, Iraq; Wasit Univ, Dept Civil Engn, Wasit 52001, Iraq.
    Zubaidi, Salah L.
    Wasit Univ, Dept Civil Engn, Wasit 52001, Iraq; Univ Warith Al Anbiyaa, Coll Engn, Karbala 56001, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Muhsen, Yousif Raad
    Wasit Univ, Dept Civil Engn, Wasit 52001, Iraq; Univ Putra Malaysia, Fac Comp Sci & Informat Technol, Dept Comp Sci, Serdang 43400, Malaysia.
    Review of Recent Trends in the Hybridisation of Preprocessing-Based and Parameter Optimisation-Based Hybrid Models to Forecast Univariate Streamflow2024In: CMES - Computer Modeling in Engineering & Sciences, ISSN 1526-1492, E-ISSN 1526-1506, Vol. 138, no 1, p. 1-41, article id 027954Article, review/survey (Refereed)
    Abstract [en]

    Forecasting river flow is crucial for optimal planning, management, and sustainability using freshwater resources. Many machine learning (ML) approaches have been enhanced to improve streamflow prediction. Hybrid techniques have been viewed as a viable method for enhancing the accuracy of univariate streamflow estimation when compared to standalone approaches. Current researchers have also emphasised using hybrid models to improve forecast accuracy. Accordingly, this paper conducts an updated literature review of applications of hybrid models in estimating streamflow over the last five years, summarising data preprocessing, univariate machine learning modelling strategy, advantages and disadvantages of standalone ML techniques, hybrid models, and performance metrics. This study focuses on two types of hybrid models: parameter optimisation-based hybrid models (OBH) and hybridisation of parameter optimisation-based and preprocessing-based hybrid models (HOPH). Overall, this research supports the idea that meta-heuristic approaches precisely improve ML techniques. It&apos;s also one of the first efforts to comprehensively examine the efficiency of various meta-heuristic approaches (classified into four primary classes) hybridised with ML techniques. This study revealed that previous research applied swarm, evolutionary, physics, and hybrid metaheuristics with 77%, 61%, 12%, and 12%, respectively. Finally, there is still room for improving OBH and HOPH models by examining different data pre-processing techniques and metaheuristic algorithms.

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  • Johansson, Lynn
    et al.
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Business Administration and Industrial Engineering.
    Jonasson, Isak
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Business Administration and Industrial Engineering.
    Reim, Wiebke
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Business Administration and Industrial Engineering.
    Sustainable expansion: Capabilities for "New food source" - Companies2023In: Future Foods, ISSN 2666-8335, Vol. 8, article id 100259Article in journal (Refereed)
    Abstract [en]

    The global climate crisis and the substantial greenhouse gas emissions associated with the food industry necessitate the flourishing of green initiatives in this sector. As a response, new food sources (NFS) have emerged as a means to shift consumption behaviors and enhance sustainability. However, NFS companies, often characterized by limited resources and expansion challenges, face difficulties in achieving sustainable growth. This research has the purpose to investigate the necessary capabilities for successful sustainable expansion within the NFS sector and develop a comprehensive framework that maps these capabilities to different stages of expansion. Through a multiple case study approach, encompassing 21 interviews conducted within the NFS sector, this study identifies five stages of sustainability work that act as drivers for sustainable expansion. Moreover, eight categories of capabilities crucial for achieving sustainable expansion are identified and ranked in a progressive manner, from fundamental to competitive advantage. Subsequently, the study establishes a framework that links the five stages of sustainable expansion with the corresponding capabilities, providing a practical guide for NFS companies seeking to pursue sustainable growth. This research contributes to the understanding of the NFS sector by uncovering key success factors for sustainable expansion. The findings offer valuable insights for NFS companies and stakeholders, informing strategic decision-making and fostering sustainable practices in the food industry.

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  • Sperlich, Billy
    et al.
    Integrative and Experimental Training Science, Institute of Sport Sciences, University of Würzburg, Würzburg, Germany.
    Düking, Peter
    Department of Sports Science and Movement Pedagogy, Technische Universität Braunschweig, Braunschweig, Germany.
    Leppich, Robert
    Software Engineering Group, Department of Computer Science, University of Würzburg, Würzburg, Germany.
    Holmberg, Hans-Christer
    Luleå University of Technology, Department of Health, Learning and Technology, Health, Medicine and Rehabilitation. Department of Physiology and Pharmacology, Biomedicum C5, Karolinska Institutet, Stockholm, Sweden.
    Strengths, weaknesses, opportunities, and threats associated with the application of artificial intelligence in connection with sport research, coaching, and optimization of athletic performance: a brief SWOT analysis2023In: Frontiers in Sports and Active Living, E-ISSN 2624-9367, Vol. 5, article id 1258562Article in journal (Refereed)
    Abstract [en]

    Here, we performed a non-systematic analysis of the strength, weaknesses, opportunities, and threats (SWOT) associated with the application of artificial intelligence to sports research, coaching and optimization of athletic performance. The strength of AI with regards to applied sports research, coaching and athletic performance involve the automation of time-consuming tasks, processing and analysis of large amounts of data, and recognition of complex patterns and relationships. However, it is also essential to be aware of the weaknesses associated with the integration of AI into this field. For instance, it is imperative that the data employed to train the AI system be both diverse and complete, in addition to as unbiased as possible with respect to factors such as the gender, level of performance, and experience of an athlete. Other challenges include e.g., limited adaptability to novel situations and the cost and other resources required. Opportunities include the possibility to monitor athletes both long-term and in real-time, the potential discovery of novel indicators of performance, and prediction of risk for future injury. Leveraging these opportunities can transform athletic development and the practice of sports science in general. Threats include over-dependence on technology, less involvement of human expertise, risks with respect to data privacy, breaching of the integrity and manipulation of data, and resistance to adopting such new technology. Understanding and addressing these SWOT factors is essential for maximizing the benefits of AI while mitigating its risks, thereby paving the way for its successful integration into sport science research, coaching, and optimization of athletic performance.

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  • Poupet, Boris
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Florisson, Sara
    Department of Materials Science and Engineering, Division of Applied Mechanics, Uppsala University, Uppsala, Sweden.
    Couceiro, José
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Sandberg, Dick
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Moisture gradients in sawn timber during aggressive kiln drying investigated with X-ray computed tomography2023In: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280Article in journal (Refereed)
    Abstract [en]

    Reducing the time for drying sawn timber to a certain moisture level without deteriorating its quality is increasingly important for an economic and energy-efficient industrial timber-drying process and to support the transition to a sustainable society. It is, however, crucial to ensure that the quality of the timber, i.e. the degree of distortion, cracking, discolouration, and moisture variation within and between the pieces in a drying batch, is not compromised. Drying-simulation software tend to be too conservative in drying-rate recommendations, which has been observed in practise particularly for large cross-section timber of Norway spruce. This study investigated the drying rate and checking occurrence of centre-yielded Norway spruce planks when dried with more aggressive schedules than normally used in practise, i.e. using higher dry-bulb temperatures and/or lower relative humidities than recommended in the conventional optimisation programmes used in the sawmill industry in Sweden. The objective was to investigate the possibility to considerably reduce the total drying time without compromising the quality of the dried timber. The quality of the planks was indirectly assessed by estimating their moisture-content distributions, calculating the moisture gradients and monitoring checking. This was achieved with 4D (3D + time) X-ray computed tomography and a recently developed image processing algorithm based on elastic image registration. The key findings in this study suggest that Norway spruce timber can be dried with significantly higher temperatures and lower relative humidities than suggested by simulations, leading to reduced total drying time without inducing checking. This methodology can help to improve the design of drying schedules to reduce drying time and energy consumption while maintaining timber quality at a level accepted by the customers.

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  • Ljunggren, Fredrik
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Simmons, Christian
    Simmons Akustik och Utveckling, Chalmers Teknikpark, Gothenburg, Sweden.
    Sound insulation in multi-family houses: Proposal of single number limits for acoustical protection and comfort2023In: Building Acoustics, ISSN 1351-010X, Vol. 30, no 4, p. 387-407Article in journal (Refereed)
    Abstract [en]

    In this paper, the acoustical quality in apartment housing is studied. The purpose is to find out to what extent occupants are annoyed by indoor noise and to compare the annoyance with measured airborne and impact sound insulation. The occupants in 38 building cases in Sweden, grouped into different construction categories, were asked in a questionnaire to rate their annoyance for a variety of potentially disturbing sound sources. In total, 1230 individual responses were used for the statistical analyses. The result shows that on average, the occupants are quite satisfied and reported low annoyance. This is taken as an indication that the present National legislation for sound insulation, airborne sound insulation included, works well. However, annoyance from footstep of walking neighbours is an exception, causing significantly greater annoyance compared to any other source, especially among occupants in lightweight buildings. The commonly used impact sound insulation descriptors are unable to match subjective experience. In combination with the sensitivity of lightweight floors to low-frequency sounds, improper building designs are likely to result in poor noise protection for the occupants. To overcome this issue, a new single number quantity taking frequencies as low as 25 Hz into account is suggested.

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  • Teern, Anna
    et al.
    M3S, University of Oulu, Oulu, 90014, Finland.
    Kelanti, Markus
    M3S, University of Oulu, Oulu, 90014, Finland.
    Päivärinta, Tero
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Digital Services and Systems. M3S, University of Oulu, Oulu, 90014, Finland.
    Karaila, Mika
    Valmet Automation Systems, Valmet Oyj, Tampere, 33900, Finland.
    Design Objectives for Evolvable Knowledge Graphs2023In: Complex Systems Informatics and Modeling Quarterly, E-ISSN 2255-9922, no 36, p. 1-15, article id 197Article in journal (Refereed)
    Abstract [en]

    Knowledge graphs (KGs) structure knowledge to enable the development of intelligent systems across several application domains. In industrial maintenance, comprehensive knowledge of the factory, machinery, and components is indispensable. This study defines the objectives for evolvable KGs, building upon our prior research, where we initially identified the problem in industrial maintenance. Our contributions include two main aspects: firstly, the categorization of learning within the KG construction process and the identification of design objectives for the KG process focusing on supporting industrial maintenance. The categorization highlights the specific requirements for KG design, emphasizing the importance of planning for maintenance and reuse.

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  • Parsaei, S.
    et al.
    Department of Nuclear Engineering, School of Mechanical Engineering, Shiraz University, Shiraz, Iran.
    Pirouzmand, A.
    Department of Nuclear Engineering, School of Mechanical Engineering, Shiraz University, Shiraz, Iran; Safety Research Center, School of Mechanical Engineering, Shiraz University, Shiraz, Iran.
    Nematollahi, M. R.
    Department of Nuclear Engineering, School of Mechanical Engineering, Shiraz University, Shiraz, Iran; Safety Research Center, School of Mechanical Engineering, Shiraz University, Shiraz, Iran.
    Ahmadi, A.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Hadad, K.
    Department of Nuclear Engineering, School of Mechanical Engineering, Shiraz University, Shiraz, Iran; Safety Research Center, School of Mechanical Engineering, Shiraz University, Shiraz, Iran.
    Effect of test-caused degradation on the unavailability of standby safety components2023In: Nuclear engineering and technology : an international journal of the Korean Nuclear Society, ISSN 1738-5733, E-ISSN 2234-358XArticle in journal (Refereed)
    Abstract [en]

    This paper proposes a safety-critical standby component unavailability model that contains aging effects caused by the elapsed time from installation, component degradation due to surveillance tests, and imperfect maintenance actions. An application of the model to a Motor-Operated Valve and a Motor-Driven Pump involved in the HPIS of a VVER/1000-V446 nuclear power plant is demonstrated and compared with other existing models at component and system levels. In addition, the effects of different unavailability models are reflected in the NPP&apos;s risk criterion, i.e., core damage frequency, over five maintenance periods. The results show that, compared with other models that do not simultaneously consider the full effects of degradation and maintenance impacts, the proposed model realistically evaluates the unavailabilities of the safety-related components and the involved systems as a plant age function. Therefore, it can effectively reflect the age-dependent CDF impact of a given testing and maintenance policy in a specified time horizon.

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  • Loudoun, Fiona M.
    et al.
    Luleå University of Technology, Department of Health, Learning and Technology, Health, Medicine and Rehabilitation. Department of Occupational Science and Occupational Therapy, University College Cork, Cork, Ireland.
    Boyle, Bryan
    Luleå University of Technology, Department of Health, Learning and Technology, Health, Medicine and Rehabilitation. Department of Occupational Science and Occupational Therapy, University College Cork, Cork, Ireland.
    Larsson-Lund, Maria
    Luleå University of Technology, Department of Health, Learning and Technology, Health, Medicine and Rehabilitation.
    Making choices in digital play spaces: Children’s experiences2023In: Scandinavian Journal of Occupational Therapy, ISSN 1103-8128, E-ISSN 1651-2014, Vol. 30, no 8, p. 1460-1471Article in journal (Refereed)
    Abstract [en]

    Background:

    Digital spaces are rapidly emerging as a space for children to engage in autotelic play.

    Aim:

    To explore and describe children’s experiences of choice-making in their play in digital spaces from the perspective of children themselves.

    Methods:

    Focus groups were conducted with a total of eight children aged six years of age within their school, in a large city in Ireland. A Mosaic Approach with drawing, cutting, and colouring in was used to elicit the children’s voices to ensure their active engagement throughout the data collection. Data was analyzed using focus group analysis.

    Results:

    Data analysis revealed three main themes; children enjoy the ability to make choices in their play, that they are often constrained in their ability to make choices, and that they negotiate ways in which they can select options for play in digital spaces.

    Conclusions:

    Findings indicate that children are agentic individuals who are capable of making decisions in their play in digital spaces. This knowledge provides implications for Occupational Therapists to enhance play as an occupation in digital spaces.

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  • Zhou, Yi
    et al.
    Changchun Institute of Technology, School of Architecture, Jilin, Changchun, China.
    Althoey, Fadi
    Department of Civil Engineering, College of Engineering, Najran University, Najran, Saudi Arabia.
    Alotaibi, Badr Saad
    Architectural Engineering Department, College of Engineering, Najran University, Najran, Saudi Arabia.
    Gamil, Yaser
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering. Department of Civil Engineering, School of Engineering, Monash University Malaysia, Selangor, Malaysia.
    Iftikhar, Bawar
    Department of Civil Engineering, COMSATS University Islamabad, Abbottabad, Pakistan.
    An overview of recent advancements in fibre-reinforced 3D printing concrete2023In: Frontiers in Materials, E-ISSN 2296-8016, Vol. 10, article id 1289340Article, review/survey (Refereed)
    Abstract [en]

    3D printing, also known as additive manufacturing, has recently gained significant attention and popularity as a transformative technology across various industries. One area where 3D printing is making remarkable strides is in the construction field, particularly with the emergence of 3D printing concrete (3DPC). While 3DPC holds immense promise, there are still challenges to overcome, such as incorporating reinforcement. This study reviews the potential of using fibre reinforcement to overcome the challenge of making ductile concrete for 3D printing that can withstand substantial tensile stresses. Effects of various types of fibre addition on widespread aspects of 3DPC are systematically reviewed. This review study considers various aspects of 3DPC: rheological characteristics, buildability, anisotropic mechanical behavior, and ductility. These characteristics of fibre-reinforced 3DPC are discussed in light of the published literature. This research’s graphical and statistical visualizations offer valuable insights for academic scholars. This review summarizes recent advancements in fibre-reinforced 3DPC while highlighting the persisting challenges in developing fibre-reinforced 3DPC with desired properties for real-world applications.

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  • Matter, Lukas
    et al.
    Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE 41296, Gothenburg, Sweden; Department of Microsystems Engineering, University of Freiburg, Georges-Köhler-Allee 201, GER 79110, Freiburg, Germany; Brainlinks-Braintools Center, University of Freiburg, Georges-Köhler-Allee 201, GER 79110, Freiburg, Germany; Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, Albertstraße 19, GER 79104, Freiburg, Germany.
    Harland, Bruce
    School of Pharmacy, The University of Auckland, NZ 1023 Auckland, New Zealand.
    Raos, Brad
    School of Pharmacy, The University of Auckland, NZ 1023 Auckland, New Zealand.
    Svirskis, Darren
    School of Pharmacy, The University of Auckland, NZ 1023 Auckland, New Zealand.
    Asplund, Maria
    Luleå University of Technology, Department of Health, Learning and Technology, Nursing and Medical Technology. Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE 41296, Gothenburg, Sweden; Department of Microsystems Engineering, University of Freiburg, Georges-Köhler-Allee 201, GER 79110, Freiburg, Germany; Brainlinks-Braintools Center, University of Freiburg, Georges-Köhler-Allee 201, GER 79110, Freiburg, Germany; Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg, Albertstraße 19, GER 79104, Freiburg, Germany.
    Generation of direct current electrical fields as regenerative therapy for spinal cord injury: A review2023In: APL Bioengineering, E-ISSN 2473-2877, Vol. 7, no 3, article id 031505Article, review/survey (Refereed)
    Abstract [en]

    Electrical stimulation (ES) shows promise as a therapy to promote recovery and regeneration after spinal cord injury. ES therapy establishes beneficial electric fields (EFs) and has been investigated in numerous studies, which date back nearly a century. In this review, we discuss the various engineering approaches available to generate regenerative EFs through direct current electrical stimulation and very low frequency electrical stimulation. We highlight the electrode-tissue interface, which is important for the appropriate choice of electrode material and stimulator circuitry. We discuss how to best estimate and control the generated field, which is an important measure for comparability of studies. Finally, we assess the methods used in these studies to measure functional recovery after the injury and treatment. This work reviews studies in the field of ES therapy with the goal of supporting decisions regarding best stimulation strategy and recovery assessment for future work.

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  • Kranenbarg, Jelle
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Jonsson, P. P.
    Vattenfall AB, R&D, Sweden.
    Mulu, B. G.
    Vattenfall AB, R&D, Sweden.
    Cervantes, Michel J.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Uncertainty in the numerical prediction of the tangential velocity in axial turbines at part load operations: A parametric study2023In: Energy Reports, E-ISSN 2352-4847, Vol. 10, p. 2597-2611Article in journal (Refereed)
    Abstract [en]

    Numerical simulations of axial hydraulic turbines away from the best efficiency point are challenging. Previous studies especially show difficulties predicting the tangential velocity at Part Load (PL) operating conditions, where the swirl is high, in comparison to experiments. This is a reoccurring problem, and it is essential to understand, as the high tangential velocity is a fundamental characteristic of the flow in hydraulic turbines and is directly related to the swirling flow stability and the turbine&apos;s power output. The objective of this study is to numerically investigate and understand the origin of the tangential velocity deviation from experimental results by performing simulations with the finite volume method of an axial turbine operated at PL. A parametric study is performed to address the abovementioned. Specifically, the effects of the blade clearance, blade angle, flow rate, and different turbulence models are studied on this issue. Results are analyzed by comparing the predicted axial and tangential velocity profiles and torque to experimentally obtained values. Primarily the runner inter-blades flow is studied as there is a knowledge gap. In addition, the physical phenomena responsible for head losses are studied in detail. Results show that the model can predict the flow relatively well at optimal flow conditions with low swirl but has problems at part load; the tangential velocity between the runner blades is underestimated by ∼20%. The undervalued head losses are the root cause. They result in an overestimated torque and an underestimated tangential velocity as the runner extracts too much energy from the fluid. A small modeling error of 0.5° in the blade angle and a change of 3% in the flow rate significantly affect the tangential velocity and torque prediction. The studied parameters must be considered carefully when building a numerical model.

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  • Khan, Yasar
    et al.
    Department of Structural Engineering, Military College of Engineering (MCE), National University of Science and Technology (NUST), Islamabad 44000, Pakistan.
    Zafar, Adeel
    Department of Structural Engineering, Military College of Engineering (MCE), National University of Science and Technology (NUST), Islamabad 44000, Pakistan.
    Rehman, Muhammad Faisal
    University of Engineering and Technology Peshawar, Abbottabad campus, Abbottabad, 22060, Pakistan.
    Javed, Muhammad Faisal
    Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, 22060, Pakistan.
    Iftikhar, Bawar
    Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, 22060, Pakistan.
    Gamil, Yaser
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering. Department of Civil Engineering, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia.
    Bio-inspired based meta-heuristic approach for predicting the strength of fiber-reinforced based strain hardening cementitious composites2023In: Heliyon, E-ISSN 2405-8440, Vol. 9, no 11, article id e21601Article in journal (Refereed)
    Abstract [en]

    A recently introduced bendable concrete having hundred times greater strain capacity provides promising results in repair of engineering structures, known as strain hardening cementitious composites (SHHCs). The current research creates new empirical prediction models to assess the mechanical properties of strain-hardening cementitious composites (SHCCs) i.e., compressive strength (CS), first crack tensile stress (TS), and first crack flexural stress (FS), using gene expression programming (GEP). Wide-ranging records were considered with twelve variables i.e., cement percentage by weight (C%), fine aggregate percentage by weight (Fagg%), fly-ash percentage by weight (FA%), Water-to-binder ratio (W/B), super-plasticizer percentage by weight (SP%), fiber amount percentage by weight (Fib%), length to diameter ratio (L/D), fiber tensile strength (FTS), fiber elastic modulus (FEM), environment temperature (ET), and curing time (CT). The performance of the models was deduced using correlation coefficient (R) and slope of regression line. The established models were also assessed using relative root mean square error (RRMSE), Mean absolute error (MAE), Root squared error (RSE), root mean square error (RMSE), objective function (OBF), performance index (PI) and Nash-Sutcliffe efficiency (NSE). The resulting mathematical GP-based equations are easy to understand and are consistent disclosing the originality of GEP model with R in the testing phase equals to 0.8623, 0.9269, and 0.8645 for CS, TS and FS respectively. The PI and OBF are both less than 0.2 and are in line with the literature, showing that the models are free from overfitting. Consequently, all proposed models have high generalization with less error measures. The sensitivity analysis showed that C%, Fagg%, and ET are the most significant variables for all three models developed with sensitiveness index higher than 10 %. The result of the research can assist researchers, practitioners, and designers to assess SHCC and will lead to sustainable, faster, and safer construction from environment-friendly waste management point of view.

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  • Heimann, Samuel
    et al.
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Humans and Technology.
    Johansson, Kristina
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Humans and Technology.
    Tosser Franklin, Wilhelm
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Humans and Technology.
    Gender in industrial mine work and organizations. A review of an expanding research field2023In: The Extractive Industries and Society, ISSN 2214-790X, E-ISSN 2214-7918, Vol. 16, article id 101371Article, review/survey (Refereed)
    Abstract [en]

    This article reviews the expanding research field of gender in industrial mine work and organizations. The findings show that the literature provides nuanced insights into the prevalence of men and masculinities in industrial mine work as related to masculine mining ideals and patriarchal family structures, gendered practices and processes within mining organizations, the strategies of marginalized identities, and counterproductive attempts to increase equality and diversity in mining. Signs of potential change were also identified in the form of empowered women in mining and alternative mining masculinities. Articles focused on women and mining in specific organizations and national contexts dominate the field, with a more heterogeneous array of articles that empirically and theoretically expand on the earlier literature. Few studies elaborate on intersectionality, various forms of masculinity and the doing of gender within various professions and occupations in mining organizations. Future research should expand the theoretical framework of gender in mining organizations and broaden its empirical base through comparative approaches, quantitative and mixed methodologies, and a renewed focus on the dominant group in mining organizations, i.e., men.

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  • Bostedt, Göran
    et al.
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Social Sciences. Department of Forest Economics, Swedish University of Agricultural Sciences, Umeå, Sweden; Umeå School of Business, Economics and Statistics, Umeå University, Umeå, Sweden; Center for Environmental and Resource Economics, CERE, Umeå, Sweden.
    Knutsson, Per
    School of Global Studies, University of Gothenburg, Gothenburg, Sweden.
    Muricho, Deborah
    Department of Land Resource Management & Agricultural Technology (LARMAT), University of Nairobi, Nairobi, Kenya.
    Mureithi, Stephen
    Department of Land Resource Management & Agricultural Technology (LARMAT), University of Nairobi, Nairobi, Kenya.
    Wredle, Ewa
    Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden.
    Nyberg, Gert
    Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Adaptive pastoralists—Insights into local and regional patterns in livelihood adaptation choices among pastoralists in Kenya2023In: Pastoralism, E-ISSN 2041-7136, Vol. 13, no 1, article id 26Article in journal (Refereed)
    Abstract [en]

    Pastoralist adaptation strategies have to address multiple, overlapping, and often inter-related processes of socio-ecological change. The present study addresses the need for inter-regional comparative studies that account for different geographic, climate, and socio-economic contexts in order to understand how pastoralists adapt to changes in livelihood conditions. The paper uses data from a unique survey study of pastoralist households in four neighbouring counties in dryland Kenya. Taking our point of departure from an empirically based classification of the livelihood strategies available to pastoralists in the Horn of Africa, the survey offers novel insights into adaptation and fodder management strategies of pastoralist individuals and households. The results show that the use of migration as a strategy is more dependent on the ability to migrate than climate conditions. This is the case in localities where a substantial part of the land is subdivided, the population density is high, and where opportunities for migration are subsequently restricted. Diversification of livelihoods as a strategy is largely defined by opportunity. Intensification through active fodder management is mainly common in areas where there has been a proliferation of managed enclosures. Climate change will test the adaptive capacity of pastoralists in the studied region, and diversification and intensification strategies of both herd composition and livelihoods can be seen as strategies for increased climate resilience.

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  • Bahaloo, Hassan
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Gren, Per
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Casselgren, Johan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Forsberg, Fredrik
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Sjödahl, Mikael
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Capillary Bridge in Contact with Ice Particles Can Be Related to the Thin Liquid Film on Ice2024In: Journal of cold regions engineering, ISSN 0887-381X, E-ISSN 1943-5495, Vol. 38, no 1, article id 04023021Article in journal (Refereed)
    Abstract [en]

    We experimentally demonstrate the presence of a capillary bridge in the contact between an ice particle and a smooth aluminum surface at a relative humidity of approximately 50% and temperatures below the melting point. We conduct the experiments in a freezer with a controlled temperature and consider the mechanical instability of the bridge upon separation of the ice particle from the aluminum surface at a constant speed. We observe that a liquid bridge forms, and this formation becomes more pronounced as the temperature approaches the melting point. We also show that the separation distance is proportional to the cube root of the volume of the bridge. We hypothesize that the volume of the liquid bridge can be used to provide a rough estimate of the thickness of the liquid layer on the ice particle since in the absence of other driving mechanisms, some of the liquid on the surface must have been pulled to the bridge area. We show that the estimated value lies within the range previously reported in the literature. With these assumptions, the estimated thickness of the liquid layer decreases from nearly 56 nm at T = −1.7°C to 0.2 nm at T = −12.7°C. The dependence can be approximated with a power law, proportional to (TM − T)−β, where β < 2.6 and TM is the melting temperature. We further observe that for a rough surface, the capillary bridge formation in the considered experimental conditions vanishes.

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  • Filizzola, Bernardo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Investigation of Influential Contexts on Mining-front Seismicity at Kiirunavaara Mine2023Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Mining at great depths has become the reality for the mining industry in Sweden, that faces challenges in terms of increasing seismic events and sometimes intrinsically related rock mass failure. Kiirunavaara mine is owned by LKAB (located at north Sweden) and the company has been dealing with seismicity in a daily basis once the mine has been regarded as seismically active since 2007-2008 and presently has the largest seismic monitoring system in the world. Several authors have studied the characteristics of seismicity at Kiirunavaara mine, but still a closer look into the factors that influence mining-front related seismicity has yet not been performed. In this sense, the present master thesis aimed to investigate the influential contexts on mining-front seismicity in Kiirunavaara mine from a production point of view (mucking data, mining-front geometry and mining sequence) and to point out probable triggers to seismic events and practical guideline measures to partly mitigate the seismic risk. For this the large seismic events (local magnitude ML ≥ 1.5) from 2011 to 2021 classified by previous studies as mining-front related have been analyzed. 63 events were initially investigated individually, combining mucking data, production data and mine geometry from GironPlot 2D and 3D views and the seismic data from software mXrap. The aim was to find patterns of contexts (in terms of mucking data, mining-front geometry and mining sequence) that are likely influential to the occurrence of large seismic events. The results allowed to reclassify the number of mining-front related seismic events to 52, and these were pointed to be probably triggered by blasting (25 events) or mucking (27 events). The events were further classified in 7 categories of probable influential contexts. Most of the events were categorized as related to the Longitudinal Mining category (19 events) and to the Stage I category (17 events). The Stage I category presents a critical scenario of stress concentration in the intact rock pillar that exists between sublevels on the initial stage of production of a level, when no connection to the cave above has been established yet. The high number of events related to the Longitudinal Mining category reinforces the suggestion of not using this type of geometry in the mine. Other categories show the relevance of having proper strategies in terms of mining sequence and mining rate between production blocks. The work brings forward relevant discussions for the future of mining in high stressed environments, e.g. how to enhance the early production stage in terms of providing better preconditioning to the cave and also highlight the importance of investigating and developing tools that could allow to increase the understanding of mucking on the mining-front related seismicity at Kiirunavaara mine.

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  • Alkhaled, Lama
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Adewumi, Oluwatosin
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Sabry, Sana Sabah
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bipol: A novel multi-axes bias evaluation metric with explainability for NLP2023In: Natural Language Processing Journal, ISSN 2949-7191, Vol. 4, article id 100030Article in journal (Refereed)
    Abstract [en]

    We introduce bipol, a new metric with explainability, for estimating social bias in text data. Harmful bias is prevalent in many online sources of data that are used for training machine learning (ML) models. In a step to address this challenge we create a novel metric that involves a two-step process: corpus-level evaluation based on model classification and sentence-level evaluation based on (sensitive) term frequency (TF). After creating new models to classify bias using SotA architectures, we evaluate two popular NLP datasets (COPA and SQuADv2) and the WinoBias dataset. As additional contribution, we created a large English dataset (with almost 2 million labeled samples) for training models in bias classification and make it publicly available. We also make public our codes.

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  • Adewumi, Oluwatosin
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Sabry, Sana Sabah
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Abid, Nosheen
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Liwicki, Foteini
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Liwicki, Marcus
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    T5 for Hate Speech, Augmented Data, and Ensemble2023In: Sci, E-ISSN 2413-4155, Vol. 5, no 4, article id 37Article in journal (Refereed)
    Abstract [en]

    We conduct relatively extensive investigations of automatic hate speech (HS) detection using different State-of-The-Art (SoTA) baselines across 11 subtasks spanning six different datasets. Our motivation is to determine which of the recent SoTA models is best for automatic hate speech detection and what advantage methods, such as data augmentation and ensemble, may have on the best model, if any. We carry out six cross-task investigations. We achieve new SoTA results on two subtasks—macro F1 scores of 91.73% and 53.21% for subtasks A and B of the HASOC 2020 dataset, surpassing previous SoTA scores of 51.52% and 26.52%, respectively. We achieve near-SoTA results on two others—macro F1 scores of 81.66% for subtask A of the OLID 2019 and 82.54% for subtask A of the HASOC 2021, in comparison to SoTA results of 82.9% and 83.05%, respectively. We perform error analysis and use two eXplainable Artificial Intelligence (XAI) algorithms (Integrated Gradient (IG) and SHapley Additive exPlanations (SHAP)) to reveal how two of the models (Bi-Directional Long Short-Term Memory Network (Bi-LSTM) and Text-to-Text-Transfer Transformer (T5)) make the predictions they do by using examples. Other contributions of this work are: (1) the introduction of a simple, novel mechanism for correcting Out-of-Class (OoC) predictions in T5, (2) a detailed description of the data augmentation methods, and (3) the revelation of the poor data annotations in the HASOC 2021 dataset by using several examples and XAI (buttressing the need for better quality control). We publicly release our model checkpoints and codes to foster transparency.

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  • Pettersson, Maria
    et al.
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Social Sciences.
    Johansson, Malin
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Social Sciences.
    Johansson, Oskar
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Social Sciences.
    Circular Economy and Sustainability: Management and Policy (Volume 1)2023In: Detrius, ISSN 2611-4127, Vol. 23, p. XI-XIIIArticle, book review (Other academic)
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  • Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Circular Economy and Sustainability: Management and Policy (Volume 2)2023In: Detrius, ISSN 2611-4127, Vol. 23, p. XIV-XVArticle, book review (Other academic)
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  • La Hera, Pedro
    et al.
    Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology, Umeå 90183, Sweden.
    Mendoza-Trejo, Omar
    Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology, Umeå 90183, Sweden.
    Lideskog, Håkan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Product and Production Development.
    Morales, Daniel Ortíz
    CRANAB AB, Vindeln 92232, Sweden.
    A framework to develop and test a model-free motion control system for a forestry crane2023In: Biomimetic Intelligence and Robotics, E-ISSN 2667-3797, Vol. 3, no 4, article id 100133Article in journal (Refereed)
    Abstract [en]

    This article has the objective of presenting our method to develop and test a motion control system for a heavy-duty hydraulically actuated manipulator, which is part of a newly developed prototype featuring a fully-autonomous unmanned forestry machine. This control algorithm is based on functional analysis and differential algebra, under the concepts of a new type of approach known as model-free intelligent PID control (iPID). As it can be unsafe to test this form of control directly on real hardware, our main contribution is to introduce a framework for developing and testing control software. This framework incorporates a desktop-size mockup crane equipped with comparable hardware as the real one, which we design and manufactured using 3D-printing. This downscaled mechatronic system allows to safely test the implementation of control software in real-time hardware directly on our desks, prior to the actual testing on the real machine. The results demonstrate that this development framework is useful to safely test control software for heavy-duty systems, and it helped us present the first experiments with the world’s first unmanned forestry machine capable of performing fully autonomous forestry tasks.

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  • Asad, Malik
    Luleå University of Technology.
    Security Management in Cloud Computing for healthcare Data2023Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    "In today's research field interconnected world, preventing security issues and confidentiality breaches has become paramount to safeguarding sensitive information, and organizations must take proactive measures to ensure data security. Cloud computing enhances security management by reducing the likelihood of cyber-attacks. The study showed that cloud computing significantly provides healthcare department scalability, flexibility, and cost efficiency. The cloud computing system consists of multiple applications operated by different sources. The study reveals that organizations must be prepared to reduce these risk factors caused by computing management.This study research objectives have evaluated the management of security in cloud computing for the healthcare data department. The main focus of this study was to highlight the impact of cloud management in providing confidential security to healthcare data along with new technologies required in healthcare. To create a dependable infrastructure for the safety of health data stored in the cloud. The study also analyzes its consequences and provides a secure cloud data risk treatment technique. It also analyzes the Information Security Management System (ISMS) framework's effectiveness and healthcare data incidence management procedure. The study mainly answers the following research questions: What is the dependable infrastructure for the safety of health data stored in the cloud? How do we secure access to cloud data and analyze its consequences? What is the effectiveness of the ISMS framework and secure technique for cloud data risk treatment in healthcare? What are the procedures for analyzing healthcare data incidence management?The research methodology of this study mainly utilizes the primary qualitative method, positivism, and deductive approach. The survey strategy, along with purposive sampling used to analyze the study objective and Questions. The data can be collected using the survey (Questionnaire), and the form can be distributed amongst participants via Qualtrics. The expected findings of the study depict that cloud computing will help healthcare to develop its security management issues. This concludes that cloud computing software in security management will significantly impact the protection of confidential healthcare data. Future researchers must consider the secondary data collection method as it will provide rich data regarding the study topic and help the healthcare sectors to reduce the risk of security management

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  • Arshad, Umair
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Revolutionizing Open Data Privacy Unveiling COBAD's Superiority over Traditional Methods2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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  • Ahmad, Mohammad khaer
    et al.
    Luleå University of Technology, Department of Health, Learning and Technology.
    Amis, Touleen
    Luleå University of Technology, Department of Health, Learning and Technology.
    Att upptäcka kvinnors våldsutsatthet i nära relationer: Röntgensjuksköterskans roll i att identifiera och bemöta2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Introduction: Violence in close relationships is a problem in society that results in serious consequences. Every third woman in the world suffers from physical, psychological or sexual violence. In Sweden, during 2022, more than 38,000 crimes of assault against women have been reported. Healthcare professionals have an important role in detecting and supporting abused women. Purpose: To describe the radiographer’s role in identifying and encountering abused women in close relationships. Method: This study has been conducted as a general literature review where data were collected from two different databases, PubMed and CINAHL. Twelve scientific qualitative and quantitative studies were quality reviewed, analyzed and presented in the form of three categories. Results: The categories that emerged in the results were identification of the structure and composition of the violence, barriers to detection and encountering victims of violence. The results showed that violence-related physical injuries occur most often in the head, neck and upper extremities. These injuries vary depending on the mechanism and severity of the violence. Psychological violence affects women's well-being. It has been shown that a lack of knowledge, guidelines and time can prevent abused women and healthcare professionals from working against violence. An empathetic and respectful encounter was considered important towards women affected by violence. Conclusion: Knowledge of how physical and psychological violence manifests is crucial for the detection and management of violence. In addition, an empathetic encounter can help abused women feel safe and willing to talk about their situation. It is important to have distinct routines and guidelines that promote better working methods and ensure that adequate measures are taken.

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  • Siddique, Md Asif Mahmod Tusher
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Harnessing the Power of Voltage-dependent Synaptic Plasticity (VDSP): A Novel Paradigm for Unsupervised Learning in Neuromorphic Systems2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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  • Public defence: 2023-12-15 10:00 E243, Luleå
    Flaquer, Berta
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Urbanization as Socionatures' Reproduction: from Territories of Extraction2023Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Through an engagement with the strand of critical urban theory, this dissertation brings the reworkings of Henri Lefebvre’s notion of ‘planetary urbanisation’ into a new synthesis with further inputs from urban political ecology and feminism—towards developing an ecofeminist lens to urbanization. Guided by the hypothesis “urbanization has been historically sustained through the patriarchal domination of women and nature’s reproduction,” the thesis seeks to critically explore how urbanization processes have historically and multiscalarly recurrently transformed the spatial configurations of reproduction from territories of extraction. It does so by engaging with the long durée historical problematique of the malm territory of extraction, as situated from Swedish Sápmi and through an intersectional ecofeminist approach. From the mid-1500s—Indigenous Sámi, Natures, and the bodies of especially women—have been violently subordinated through patriarchal-colonial-capitalist urbanization processes. Across scales and time, the so-called production has been designed by and for the BWMAh* as extraction. Through the malm territory—within and beyond Sweden—this has taken the form of iron ore mining, but also historically in linkage with other forms (i.e. fur and leather, large-scale reindeer, fishing, agriculture, forestry, coal, hydropower, research and development, tourism, data centres, fertilizers, space industry, dredging, fossil-free steel, or fossil- free hydrogen). Backgrounded and at the basis, however, extraction has been sustained through the violent domination of nature and women’s reproduction, as through the witch-hunts in different forms historically and still ongoing, femicides, the creation of the ideals of ‘the good woman,’ the myth of ‘the strong Sámi women,’ successive scientific revolutions, race biology, genetics, industrial colonialism, or the new green colonialism. Under the current ‘green everything’ transition where once again capital’s project is rearticulating and preparing for the next wave of accumulation underway—through an ever-backgrounded and deeper preceding crisis of reproduction—, it is ever more relevant to question the spatiality of the reproduction processes and the ways in which earlier rearticulations have dominated the reproduction of life in new forms.

    The malm territory is then synchronically and diachronically mapped yet foregrounding the processes of subordination of nature and women—across scales and time—building up the ‘palimpsests of extraction.’ It uses Corboz’s metaphor of ‘the territory as palimpsest’ and expands its conception as a mapping method beyond cartography, to explore in which ways reproduction relations have been masked and not represented historically. The dissertation then goes on to argue that the existing literature on planetary urbanisation has been giving ontological priority to production, and this has precluded an analysis of the actual reproduction relations that have been at the root sustaining life however subordinated in the complete urbanization of society. By advancing an ecofeminist materialist lens to urbanization that reads—representationally and spatially—grasping the complex specificities through the key moments of rearticulation of patriarchal-colonial-capitalist urbanization—temporally and multiscalarly—in the long durée history of the malm territory yet foregrounding the forms of subordination of nature and women, I focus on the linkages that can be drawn between the relations of domination and alternatively collectively transformed.

    * BWMAh: Bourgeois White Male Adult heterosexual

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  • Sixtensdotter, Lova
    Luleå University of Technology, Department of Social Sciences, Technology and Arts.
    Står Centerpartiets ideologi stadigt i den levande politiken?: En kvalitativ ideologianalys2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Centerpartiet, som är ett av Sveriges riksdagspartier, har länge profilerat sig som liberala och samarbetat i politikens borgerliga allians. Från 2010 har det politiska läget i Sverige genomgått stora politiska förändringar vilket gjort att Centerpartiet idag verkar i den ’breda mitten’ och profilerar sig med en ‘mittenidentitet’. Huruvida denna turbulenta tid påverkat partiets ideologiska förändringar har därför undersökts i denna studie. Syftet som ligger till grund för studien är att studera ideologisk förändring för Centerpartiet under en politiskt turbulent tid. Den teoretiska ansatsen utgår från Marie Demkers teori om ideologisk förändring samt tre idealtyper av ideologierna konservatism, socialliberalism samt nyliberalism. Den valda metoden är kvalitativ ideologianalys, med detta menas att utvalda valmanifest kommer att läsas och innehållet kommer att tolkas och kategoriseras utifrån ett analysverktyg. I det aktuella fallet är analysverktyget en tabell som utgår från de ovan nämnda idealtyper kombinerat med definitionen av begreppen frihet, människosyn, ekonomiskt system, individ/samhälle och offentligt/privat. Valmanifesten läses i sin helhet och innehållet kategoriseras in i tabellen för att kartlägga ideologin. Genom att analysera resultatet kan en slutsats om eventuell ideologisk förändring dras.

    I studiens fall visade resultatet att Centerpartiet inte har genomgått någon ideologisk förändring, partiet har bedrivit en socialliberal politik från 2010 till 2022.

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  • Holmgren, Anna-Carin
    et al.
    Luleå University of Technology, Department of Health, Learning and Technology, Education, Language, and Teaching.
    Backman, Ylva
    Luleå University of Technology, Department of Health, Learning and Technology, Education, Language, and Teaching.
    Gardelli, Viktor
    Luleå University of Technology, Department of Health, Learning and Technology, Education, Language, and Teaching.
    Gyllefjord, Åsa
    Luleå University of Technology, Department of Health, Learning and Technology, Education, Language, and Teaching.
    On Being Twice Exceptional in Sweden - An Interview-Based Case Study about the Educational Situation for a Gifted Student Diagnosed with ADHD2023In: Education Sciences, E-ISSN 2227-7102, Vol. 13, no 11, article id 1120Article in journal (Refereed)
    Abstract [en]

    The gifted education research area is rapidly expanding in Sweden. In the context of very limited research nationally, demands are increasing for steering documents and addressing of student and teacher needs in practice. However, Swedish research on students that are ‘twice exceptional’—students classified as being both gifted and disabled (for instance, through a neurodevelopmental disorder such as ADHD)—is nearly non-existent. In this study, we present an exploratory single case study of a female student in school year seven based on semi-structured individual interviews with the student and her two guardians regarding her educational situation. The data were first inductively coded and triangulated in collaboration between three of the authors. A fourth author later independently and deductively coded one-third of the data based on the previously inductively determined thematic structure and conducted a consensus interrater reliability check, exceeding 85% percent agreement. The three main themes are as follows: (1) multiplex perspectives on academic outcomes and expectations, (2) the intersection between twice exceptionality and academic work, and (3) information and perceptions about twice exceptionality. The results indicate several educational challenges and opportunities for twice exceptional students. Further research is needed regarding twice exceptional students in Sweden.

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  • Olsson, Alexander
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Music, Media and Theater.
    Kan man öva improvisation?: Att göra ett improviserat preludium innehållande trio och fuga.2023Independent thesis Basic level (degree of Bachelor of Fine Arts), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna uppsats handlar om konsten att uppöva förmåga till improvisation på orgel. Den tar upp frågor kring hur de s.k. musikaliska parametrarna spelar in vid improvisation, vilken plats improvisationen kan ha vid en gudstjänst samt hur jag gick tillväga för att uppöva en förmåga till Preludium innehållande trio och fuga. Det bestod i en klar kombination av teori via litteratur och föreläsning samt praktik med eget övande och analyserande. Reslutaten visar att det går att uppöva ändamålsenlig förmåga till improviserat spel på orgel, att det de musikaliska parametrarna spelar en central roll samt att gudstjänsten erbjudet tillfällen för organisten att improvisera.

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  • Nilsson, Peter
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Prototyping and manufacturing of air-controlled damper unit to improve cooling system operating efficiency for data centers2023Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    More and more people are using the internet for data processing, transfer, and storage. With it comes a higher demand for computational power from data servers. Unsurprisingly, the data center industry is becoming an increasingly large industry that is important for people’s daily lives. Data centers cover 2 % of the world’s total electrical consumption and this number is expected to become higher. Running data centers with optimal performance while operating efficiently and as sustainably as possible is a task that is of utmost importance.The way data centers are cooled today is through a CRAH unit that features cooling coils and a fan, the fan blows air over cold coils to prevent damage to server components. Another task for this fan is to create a high differential pressure over the servers using this air, to ensure the air flows in the right direction. The air is uniformly distributed over the servers. With dynamic air-handling measures, it is possible to match the cooling for individual servers, because all servers have different workloads. They generate different amounts of heat. This thesis investigates manual redistribution between servers and how an air-handling damper unit, that sits on the server, is designed to investigate how it can reduce total power draw. Different tests are run in a wind tunnel which houses room for six servers whereas three prototypes are mounted on three of the servers. The main idea to test is that instead of running an even amount of stress on six servers, the same amount of stress is redistributed on only three servers. The ones now running idle have a damper unit blocking the server's rear side. That way the CRAH fan is using less power to create the same differential pressure. Also, the total power draw to all servers is reduced as well. One of the tests was the conventional way of cooling servers today and it had a total power draw of 1362 watts. The test with both redistribution, dampers closed at the rear and turned off servers had a power draw of 951 watts. That is a 30% decrease.

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  • Gull, Anna-Lena
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction. Byggdialog Dalarna.
    Erikshammar, Jarkko
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Stehn, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Vem driver utvecklingen av massiva träbyggandet?2023In: Bygg & teknik, ISSN 0281-658X, Vol. 4, p. 14-16Article in journal (Other (popular science, discussion, etc.))
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