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  • Sas, Gabriel (Editor)
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Gonzalez-Libreros, Jaime (Editor)
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Wang, Chao (Editor)
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Pinar, Mert (Editor)
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Condition Assessment of Existing Bridges: A Case Study of The Kalix Bridge2024Report (Other academic)
    Abstract [en]

    This document is the final report for project BBT 2020-013 (Trafikverket). It presents the results for the development and testing of a loading system based on realistic convoy loads for serviceability limit state (SLS) applied to the Kalix Bridge. It also includes a determination of the bridge condition through non-destructive testing (NDT) and assessment of non-destructive methods for the determination of residual prestressing forces. The work carried out included the development of linear and non-linear finite element models and their calibration, based on the information collected in the experimental part. Digital twin models intended for the prediction of bridge response were also created, and novel AI-based methods for crack detection were evaluated. In addition, a framework for condition management based on reliability and robustness parameters was developed within the scope of the project. As the Kalix Bridge was replaced by a new structure in 2022, the report summarizes a comprehensive review of methods for demolition of prestressed bridges and presents a methodology for demolition based on numerical analysis of the structure, considering the specific characteristics of the project and existing information about the bridge.

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  • Rauf, Lanja F.
    et al.
    Department of Geology, College of Science, University of Sulaimani, Sulaymaniyah 460013, Iraq; College of Engineering, Komar University of Science and Technology, Sulaymaniyah, Kurdistan Region 46001, Iraq.
    Ali, Salahalddin S.
    College of Engineering, Komar University of Science and Technology, Sulaymaniyah, Kurdistan Region 46001, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sustainability indicator for evaluating the ATES system in Halabja-Khurmal sub-basin NE-Iraq using GIS-based MCDA method2024In: Applied water science, ISSN 2190-5487, E-ISSN 2190-5495, Vol. 14, no 6, article id 137Article in journal (Refereed)
    Abstract [en]

    Thermal energy is utilized as an environmentally friendly energy source for seasonal heat and cold storage on a global scale. Specifically, the aquifer thermal energy storage system is highlighted for being cost-effective in cooling and heating applications. The study assesses the sustainability of the aquifer thermal energy storage in the Halabja-Khurmal sub-basin by evaluating six critical criteria: groundwater transmissivity, groundwater temperature, groundwater discharge, groundwater chemistry, population density, and per capita GDP. A multi-criteria decision analysis judgment is applied to analyze all criteria, resulting in a consistency ratio of 0.3% in the analytical hierarchy process. Consequently, the sustainability map for Aquifer Thermal Energy Storage in the Halabja-Khurmal sub-basin for heating reveals that 26.45% of the area is strongly sustainable located in the north and southwestern part of the sub-basin, 73.53% is moderate in the east, central, southeast, and southern regions, 0.02% is weakly sustainable as a tiny area in the southwestern. On the other hand, the sustainability map for Aquifer Thermal Energy Storage in the Halabja-Khurmal sub-basin for cooling reveals that 19% of the area is strongly sustainable located in the north, and southwestern parts of the sub-basin, 78% is moderate in the northeast, east, southeast, west, central, and southern regions, 3% is weakly sustainable as spots in the west and southwestern areas. 

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  • Gupta, Sanjeev
    et al.
    Department of Soil and Water Conservation Engineering, G.B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, 263145, India.
    Kumar, Pravendra
    Department of Soil and Water Conservation Engineering, G.B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, 263145, India.
    Kishore, Gottam
    ICAR-Central Institute of Agricultural Engineering, Bhopal, Madhya Pradesh, India.
    Ali, Rawshan
    Civil Engineering Department, University of Raparin, Rania, Kurdistan Region, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Vishwakarma, Dinesh Kumar
    Department of Irrigation and Drainage Engineering, G.B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, 263145, India.
    Kuriqi, Alban
    CERIS, Instituto Superior T´Ecnico, Universidade de Lisboa, 1049-001, Lisbon, Portugal; Civil Engineering Department, University for Business and Technology, 10000, Pristina, Kosovo.
    Pham, Quoc Bao
    Faculty of Natural Sciences, Institute of Earth Sciences, University of Silesia in Katowice, Będzińska Street 60, 41-200, Sosnowiec, Poland.
    Kisi, Ozgur
    Faculty of Natural Sciences and Engineering, Ilia State University, 0162, Tbilisi, Georgia; Department of Civil Engineering, University of Applied Sciences, 23562, Lübeck, Germany.
    Heddam, Salim
    Faculty of Science, Agronomy Department, Hydraulics Division, Laboratory of Research in Biodiversity Interaction Ecosystem and Biotechnology, University 20 août 1955, Route El Hadaik, BP 26, Skikda, Algeria.
    Mattar, Mohamed A.
    Department of Agricultural Engineering, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh, 11451, Saudi Arabia.
    Sensitivity of daily reference evapotranspiration to weather variables in tropical savanna: a modelling framework based on neural network2024In: Applied water science, ISSN 2190-5487, E-ISSN 2190-5495, Vol. 14, no 6, article id 138Article in journal (Refereed)
    Abstract [en]

    Accurate prediction of reference evapotranspiration (ETo) is crucial for many water-related fields, including crop modelling, hydrologic simulations, irrigation scheduling and sustainable water management. This study compares the performance of different soft computing models such as artificial neural network (ANN), wavelet-coupled ANN (WANN), adaptive neuro-fuzzy inference systems (ANFIS) and multiple nonlinear regression (MNLR) for predicting ETo. The Gamma test technique was adopted to select the suitable input combination of meteorological variables. The performance of the models was quantitatively and qualitatively evaluated using several statistical criteria. The study showed that the ANN-10 model performed superior to the ANFIS-06, WANN-11 and MNLR models. The proposed ANN-10 model was more appropriate and efficient than the ANFIS-06, WANN-11 and MNLR models for predicting daily ETo. Solar radiation was found to be the most sensitive input variable. In contrast, actual vapour pressure was the least sensitive parameter based on sensitivity analysis. 

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  • Hosseini, S. H.
    et al.
    Univ Tehran, Inst Geophys, Kargar Shomali, Tehran, Iran.
    Oskooi, Behrooz
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering. Univ Tehran, Inst Geophys, Kargar Shomali, Tehran, Iran.
    Ghanbarifar, S.
    Univ Tehran, Inst Geophys, Kargar Shomali, Tehran, Iran.
    Ghiasi, S. M.
    Univ Tehran, Inst Geophys, Kargar Shomali, Tehran, Iran.
    Abedi, M.
    Univ Tehran, Coll Engn, Sch Min Engn, Tehran, Iran.
    Smirnov, Maxim Y.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    2D sharp boundary inversion to determine tectonic and geological features of geothermal fields through the magnetotelluric method: case study of the Mahallat reservoir in Iran2024In: Bulletin of Geophysics and Oceanography, ISSN 2785-339XArticle in journal (Refereed)
    Abstract [en]

    Multiple processing approaches were applied to magnetotelluric data from the Mahallat geothermal field in central Iran to evaluate the dimensionality and geoelectric strike of the subterranean structures, as well as to comprehend the overall geometry of the targeted reservoir. While conventional smooth inversion methods can generate reliable models, their application, in the absence of initial information, may lead to unrealistic outcomes, especially in media with sharp resistivity contrasts. Consequently, a conventional smooth inversion, alongside the sharp boundary inversion techniques, is applied on real data through two profiles in order to investigate and compare the subsurface structural features. Ultimately, by adopting a target -oriented modelling approach, this study utilises the sharp boundary method to deduce a more suitable configuration for the characteristics of the geothermal reservoir. Thus, to a large extent, this approach can facilitate the interpretational complications of underground geothermal structures. Correspondingly, this research led to recognising a hydrothermal reservoir with a proper layout at a depth of 1,800 and 1,200 m underneath profiles A and B, respectively. Moreover, deeper reservoirs were identified and depicted as conceptual geological models obtained through the incorporation of sharp boundary inversion results and geological information.

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  • Zvarivadza, Tawanda
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Onifade, Moshood
    Institute of Innovation, Science and Sustainability, Federation University Australia, Ballarat, Victoria, Australia.
    Dayo-Olupona, Oluwatobi
    School of Mining Engineering, University of the Witwatersrand, Johannesburg, South Africa.
    Said, Khadija Omar
    Department of Energy and Mineral Engineering, Pennsylvania State University, State College, PA, USA.
    Githiria, Joseph Muchiri
    School of Mining Engineering, University of the Witwatersrand, Johannesburg, South Africa.
    Genc, Bekir
    School of Mining Engineering, University of the Witwatersrand, Johannesburg, South Africa.
    Celik, Turgay
    School of Electrical and Information Engineering, University of the Witwatersrand, Johannesburg, South Africa.
    On the impact of Industrial Internet of Things (IIoT) - mining sector perspectives2024In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949Article in journal (Refereed)
    Abstract [en]

    The application of the Internet of Things (IoT) in industrial systems and other new technological advancements led to the development of the Industrial Internet of Things (IIoT). IIoT can help overcome the shortcomings of the conventional monitoring and control system while enabling enterprises to create a unified monitoring system to automate operations, provide a safe working environment, enforce compliance effectively, and regulate environmental issues. Given the advantages that IoT brings to the forefront, it makes sense that so many mining companies have raised their investment following the implementation of IoT-enabled solutions in their organisations. To increase safety, productivity, and environmental sustainability in mining operations, this article examines the current state of information technology in the mineral industry with an emphasis on the implications and challenges brought on by the technological diversity of various systems and devices used in those activities. The study contributes valuable insights into the integration of IoT technologies in the mining industry, highlighting its potential to improve safety, efficiency, and sustainability. The paper paves the way for future research and development efforts aimed at overcoming the challenges of adopting IIoT in mining operations by identifying gaps and proposing a comprehensive IoT architecture. The innovations of the study are encapsulated in its approach to detailing the application of IoT technologies in enhancing mining operations and the establishment of an overall IIoT architecture suitable for the general operations in the mining industry.

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  • Volpp, Jörg
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Product and Production Development. Department of Engineering Science, University West, Trollhattan, 461 86, Sweden.
    Surface Tension Estimation of Steel above Boiling Temperature2024In: Applied Sciences, E-ISSN 2076-3417, Vol. 14, no 9, article id 3778Article in journal (Refereed)
    Abstract [en]

    Surface tension is an important characteristic of materials. In particular at high temperatures, surface tension values are often unknown. However, for metals, these values are highly relevant in order to enable efficient industrial processing or simulation of material behavior. Plasma, electron or laser beam processes can induce such high energy inputs, which increase the metal temperatures to, and even above, boiling temperatures, e.g., during deep penetration welding or remote cutting. Unfortunately, both theoretical and experimental methods experience challenges in deriving surface tension values at high temperatures. Material models of metals have limitations in explaining complex ion interactions, and experimentally measuring temperature and surface tension at high temperatures is a challenge for methods and equipment. Therefore, surface wave analysis was conducted in this work to derive surface tension values around the boiling temperature of steel and identify trends. In addition, a simple ion interaction calculation was used to simulate the impacting parameters that define the surface tension. Since both the experimental values and simulation results indicate an increasing trend in surface tension above the boiling temperature, it is concluded that the dominating attractive forces above this temperature should increase with increasing temperature and lead to increasing surface tension forces in the surface layers of liquid metal.

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  • Savvides, Andreas
    et al.
    Department of Architecture, University of Cyprus, Nicosia, Cyprus.
    Vassiliades, Constantinos
    Department of Architecture, Land and Environmental Sciences, Neapolis University of Pafos, Cyprus.
    Lau, Kevin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Rizzo, Agatino
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Examining user thermal comfort in spaces between buildings: Exploring parametric solutions for BIPVs for Luleå, Sweden, and Limassol, Cyprus2024In: Energy Reports, E-ISSN 2352-4847, Vol. 11, p. 5235-5251Article in journal (Refereed)
    Abstract [en]

    This research delves into the relationship between urban layouts, energy dynamics, and the thermal comfort of public spaces between buildings. Focusing on the contrasting climates of Luleå, Sweden, and Limassol, Cyprus, the study employs ENVI-met, a microscale urban climate simulation tool, for a parametric exploration at the city block scale. Assessing eight distinct scenarios across morning, noon, and afternoon timeframes, the research considers the impact of Building-Integrated Photovoltaics (BIPVs) on user thermal comfort. Contrary to expectations, the study reveals that BIPV integration alone may not be the primary driver of improved thermal comfort during peak heat periods. Instead, factors like urban density and urban morphology emerge as influential contributors. For instance, increasing the urban fabric density by doubling the building height resulted in greater PET fluctuations ranging from −3 to +3 degrees, compared to the modest PET fluctuations ranging from 0 to +3 degrees observed with the simple integration of PVs onto buildings. These findings offer valuable insights for urban planners and policymakers, guiding decisions in considering the issue of thermal comfort in public spaces between buildings, while optimizing energy consumption in urban areas.

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  • Jones, Mitchell P.
    et al.
    Polymer & Composite Engineering (PaCE) Group, Institute of Materials Chemistry and Research, Faculty of Chemistry, University of Vienna, Währinger Straße 42 1090 Vienna, Austria.
    Bismarck, Alexander
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Polymer & Composite Engineering (PaCE) Group, Institute of Materials Chemistry and Research, Faculty of Chemistry, University of Vienna, Währinger Straße 42 1090 Vienna, Austria.
    Mycomining: perspective on fungi as scavengers of scattered metal, mineral, and rare earth element resources2024In: RSC Sustainability, E-ISSN 2753-8125, Vol. 2, no 5, p. 1350-1357Article, review/survey (Refereed)
    Abstract [en]

    Mining provides raw materials critical to our energy, agriculture, infrastructure, and technology but is associated with many environmental challenges. Resource recovery alternatives like urban mining rely on inconsistent supply streams and complicated disassembly and sorting, while extreme mining alternatives such as deep sea and space mining are potentially even less sustainable than traditional mining. This perspective investigates biological mining with emphasis on the potential of fungi for scavenging metals, minerals, and rare earth elements. “Mycomining” produces only biomass-based organic waste and can offer more versatile growth conditions than phytomining using hyperaccumulating plants including substrates ranging from soil, wood, water, and rock to living organisms and dark, space-restricted, or extreme i.e., pH levels, high salt, acidic, radioactive environments. This concept could represent a useful supplement to urban and phytomining to offset demand for traditional mining and is particularly viable when conventional mining may be inefficient or uneconomical i.e., with low-grade ores and sites unsuited to traditional mining for geographical, political, or social reasons.

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  • Husin, Mohamad Nazri
    et al.
    Special Interest Group on Modeling and Data Analytics, Faculty of Computer Science and Mathematics, Universiti Malaysia Terengganu, Malaysia.
    Khan, Abdul Rauf
    Department of Mathematics, Faculty of Sciences, Ghazi University, Dera Ghazi Khan, Pakistan.
    Awan, Nadeem Ul Hassan
    Department of Mathematics, Faculty of Sciences, Ghazi University, Dera Ghazi Khan, Pakistan.
    Campena, Francis Joseph H.
    Department of Mathematics and Statistics, De La Salle University, Philippines.
    Tchier, Fairouz
    Mathematics Department, College of Science, King Saud University, Riyadh, Saudi Arabia.
    Hussain, Shahid
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Multicriteria decision making attributes and estimation of physicochemical properties of kidney cancer drugs via topological descriptors2024In: PLOS ONE, E-ISSN 1932-6203, Vol. 19, no 5, article id e0302276Article in journal (Refereed)
    Abstract [en]

    This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Based on topological descriptors, QSPR analysis is an incredibly helpful statistical method for examining many physical and chemical properties of compounds without demanding costly and time-consuming laboratory tests. Firstly, we discuss and provide research on kidney cancer drugs using topological indices and done partition of the edges of kidney cancer drugs which are based on the degree. Secondly, we examine the attributes of nineteen drugs casodex, eligard, mitoxanrone, rubraca, and zoladex, etc and among others, using linear QSPR model. The study in the article not only demonstrates a good correlation between TIs and physical characteristics with the QSPR model being the most suitable for predicting complexity, enthalpy, molar refractivity, and other factors and a best-fit model is attained in this study. This theoretical approach might benefit chemists and professionals in the pharmaceutical industry to forecast the characteristics of kidney cancer therapies. This leads towards new opportunities to paved the way for drug discovery and the formation of efficient and suitable treatment options in therapeutic targeting. We also employed multicriteria decision making techniques like COPRAS and PROMETHEE-II for ranking of said disease treatment drugs and physicochemical characteristics.

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  • Mårtensson, August
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering. Brandkonsulten AB, Stockholm, Sweden.
    New methods for testing fire resistance of wood façade systems2016In: 2nd International Seminar for Fire Safety of Facades, FSF 2016 / [ed] Stephanie Vallerent, EDP Sciences , 2016, article id 02003Conference paper (Refereed)
    Abstract [en]

    Arson in schools has been a huge problem in Sweden over the last fifteen years. The average amount of school arsons between 2000 and 2014 was 285 cases each year which corresponds to 50% of the total amount of reported fires in school buildings. This is a well-known problem and a lot of research has been done in this area. Investigations has been done about fire and heat detection systems, different technical factors significance in fire scenarios and how to prevent adolescents from starting fires. Another part of the problem that partly been investigated is how the schools are constructed. Roughly 50% of the arsons are outside of the school building. In Sweden one and two storey buildings are allowed to be built with wooden façades in accordance with the building code, which is one of the reasons many schools are built with wooden façade systems. The most critical part in a wood façade system from a fire safety perspective is concluded to be the eaves because of how they usually are built to let air pass through. Even though a wood façade isn't as well resistant to fire compared to a concrete façade, three versions of new test methods for combustible façades have been developed to make it possible to make sure in advance that a construction is resistant enough. The new test methods are focused on specific details and parts of a façade system to provide a more informative and useful result compared to SP Fire 105. Observations and measurements of flame spread and temperature changes in the eave, over the window joints and in the air gap are made. With these parameters in consideration criteria's has been chosen for a critical temperature of 280 °C at a critical time of 20 minutes.

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  • Murad, Sadia
    et al.
    Department of Soil Science, Faculty of Agriculture and Environment, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan.
    Ahmad, Maqshoof
    Department of Soil Science, Faculty of Agriculture and Environment, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan.
    Hussain, Azhar
    Department of Soil Science, Faculty of Agriculture and Environment, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan.
    Ali, Sajjad
    Department of Entomology, Faculty of Agriculture and Environment, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Mattar, Mohamed A.
    Department of Agricultural Engineering, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia.
    Efficacy of DAP coated with bacterial strains and their metabolites for soil phosphorus availability and maize growth2024In: Scientific Reports, E-ISSN 2045-2322, Vol. 14, article id 11389Article in journal (Refereed)
    Abstract [en]

    Phosphorus (P) use efficiency in alkaline/calcareous soils is only 20% due to precipitation of P2O5 with calcium and magnesium. However, coating Diammonium Phosphate (DAP) with phosphorus solubilizing bacteria (PSB) is more appropriate to increase fertilizer use efficiency. Therefore, with the aim to use inorganic fertilizers more effectively present study was conducted to investigate comparative effect of coated DAP with PSB strains Bacillus subtilis ZE15 (MN003400), Bacillus subtilis ZR3 (MN007185), Bacillus megaterium ZE32 (MN003401) and Bacillus megaterium ZR19 (MN007186) and their extracted metabolites with uncoated DAP under axenic conditions. Gene sequencing was done against various sources of phosphorus to analyze genes responsible for phosphatase activity. Alkaline phosphatase (ALP) gene amplicon of 380bp from all tested strains was showed in 1% w/v gel. Release pattern of P was also improved with coated fertilizer. The results showed that coated phosphatic fertilizer enhanced shoot dry weight by 43 and 46% under bacterial and metabolites coating respectively. Shoot and root length up to 44 and 42% with metabolites coated DAP and 41% with bacterial coated DAP. Physiological attributes also showed significant improvement with coated DAP over conventional. The results supported the application of coated DAP as a useful medium to raise crop yield even at lower application rates i.e., 50 and 75% DAP than non-coated 100% DAP application which advocated this coating technique a promising approach for advancing circular economy and sustainable development in modern agriculture.

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  • Sörqvist, Patrik
    et al.
    Luleå University of Technology, Department of Health, Education and Technology, Health, Medicine and Rehabilitation. Department of Building Engineering, Energy Systems and Sustainability Science University of Gävle, Gävle, Sweden.
    Lindeberg, Sofie
    Department of Building Engineering, Energy Systems and Sustainability Science University of Gävle, Gävle, Sweden.
    Marsh, John Everett
    Luleå University of Technology, Department of Health, Education and Technology, Health, Medicine and Rehabilitation. Human Factors Laboratory, School of Psychology and Computer Sciences University of Central Lancashire, Preston, UK.
    All's eco‐friendly that ends eco‐friendly: Short‐term memory effects in carbon footprint estimates of temporal item sequences2024In: Applied Cognitive Psychology, ISSN 0888-4080, E-ISSN 1099-0720, Vol. 38, no 3, article id e4204Article in journal (Refereed)
    Abstract [en]

    When people estimate the summative carbon footprint of a sequence of events, how are the individual events integrated? In three experiments, we found that summative carbon footprint judgments of item sequences are disproportionately influenced by items at the end of the sequence in comparison with those at the beginning—a recency effect. When, for example, sequences ended with a low carbon footprint item, they were assigned a lower carbon footprint than corresponding sequences with an identical content but different item order. The results also revealed that a green peak (presenting many low carbon footprint items at once) had a relatively large effect on estimates when the peak was contextually distinct from other items in terms of its valence. The results are consistent with an account within which distinctiveness of representations within short-term memory differentially influences decision-making and suggest that memory processes bias the perceived environmental footprint of temporally separated instances.

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  • Tossavainen, Timo
    et al.
    Luleå University of Technology, Department of Health, Education and Technology, Education, Language, and Teaching.
    Johansson, Claes
    Luleå Upper Secondary School, Sweden.
    Juhlin, Alf
    Luleå Upper Secondary School, Sweden.
    Wedestig, Anna
    Luleå Upper Secondary School, Sweden.
    Programming as a mediator of mathematical thinking: Examples from upper secondary students exploring the definite integral2024In: LUMAT: International Journal on Math, Science and Technology Education, E-ISSN 2323-7112, Vol. 12, no 3, p. 78-99Article in journal (Refereed)
    Abstract [en]

    We report on three episodes from a case study where upper secondary students numerically explore the definite integral in a Python environment. Our research questions concern how code can mediate and support students' mathematical thinking and what kind of sociomathematical norms emerge as students work together to reach a mutual understanding of a correct solution. The main findings of our investigation are as follows. 1) Students can actively use code as a mediator of their mathematical thinking, and code can even serve as a bridge that helps students to develop their mathematical thinking collaboratively. Further, code can help students to perceive mathematical notions as objects with various properties and to communicate about these properties, even in other semiotic systems than the mathematical language. 2) For the participating students, a common norm was that an acceptable solution is a sufficient condition for the correctness of the solution method although students were aware of a problem in their code, yet also other norms emerged. This demonstrates that learning mathematics with programming can have an effect on what kind of sociomathematical norms emerge in classroom.

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  • Larsson, Sofia I.A.
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Lycksam, Henrik
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Ainegren, Mats
    Sports Tech Research Centre, Department of Engineering, Mathematics, and Science Education, Mid Sweden University, Östersund, Sweden.
    Towards flow field measurements around dynamic cross-country skiers2024In: Current Issues in Sport Science (CISS), E-ISSN 2414-6641, Vol. 9, no 3, article id 006Article in journal (Refereed)
    Abstract [en]

    Flow field measurements around cross-country skiers (xc skiers) are lacking in the literature to date. The aim was therefore to investigate the possibility of using particle tracking velocimetry for visualization and measurement of the flow field around xc skiers roller skiing on a treadmill in a wind tunnel. The airflow was seeded with neutrally buoyant helium-filled soap bubbles as tracer particles, following the flow without affecting it. As illumination, two different approaches were tested: first, a laser in the cameras’ line of sight (sagittal plane), then an LED unit directed vertically in a narrow slice, clearly limiting the depth of the measurement volume in the cameras’ line of sight. The flow field was studied at various speeds (3-7 m/s) around a single skier as well as around two skiers in line with the streaming airflow. It was found that the experimental approach has the potential to provide detailed insights, both qualitatively and quantitatively, into the flow field dynamics. The main challenges regarding setup, illumination, seeding, and cameras were identified, and possible improvements to streamline the experimental methodology were discussed. 

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  • Udén, Maria
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Humans and Technology.
    A first exploration regarding gender segregated green entrepreneurship in Norrbotten and indications of theory that might be of interest.2024Report (Other academic)
    Abstract [en]

    The GENGREEN project's main objective is to develop a cross-border recognized program for green entrepreneurial training directed to women. This is a first report on the Status of (Gender segregated) Green Entrepreneurship from the Swedish Partner Luleå University of Technology. About 3 500 women in Norrbotten may be counted as entrepreneurs. This would cover business owners in executive positions and self-employment. One topic of interest concerns the percentage of women entrepreneurs at regional level, who focus on sustainable/green activities. No data or estimation that can shed light on this could be identified. Regarding Norrbotten's “Green transitions”, the current trend is investments in heavy industry that generate entrepreneurial opportunities in male dominated branches. Relevant training and applicable formal education for green women entrepreneurs are offered by among other, ALMI and Luleå University of Technology.

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  • Robertson, Jeandri
    et al.
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Business Administration and Industrial Engineering. University of Cape Town, South Africa.
    Ferreira, Caitlin
    Graduate School of Business, University of Cape Town, Cape Town, South Africa.
    Botha, Elsamari
    UC Business School, University of Canterbury, Christchurch, New Zealand.
    Oosthuizen, Kim
    University of Stellenbosch Business School, Cape Town, South Africa.
    Game changers: A generative AI prompt protocol to enhance human-AI knowledge co-construction2024In: Business Horizons, ISSN 0007-6813, E-ISSN 1873-6068Article in journal (Refereed)
    Abstract [en]

    The democratization of powerful artificial intelligence (AI) tools, including ChatGPT, has sparked the interest of business practitioners given their ability to fundamentally change the way we work. While AI tools are positioned to augment human capabilities, their effective implementation requires the skill to understand where, when and how to best utilize them efficiently. Furthermore, meaningful engagement with the content produced by generative AI (GenAI) necessitates the intricacy of appropriate prompt engineering to optimize the learning process. As the field of GenAI continues to advance, the art of developing impactful prompts has become a necessary skill for harnessing its full potential. This research develops an AI prompting protocol through a constructivist theory lens. Based on the principles of constructivism, where individuals assimilate new knowledge by bridging it with their existing understanding, this research suggests an active engagement process in the human-AI co-construction of knowledge through GenAI. The goal is to empower business managers and their teams to construct effective AI prompts and validate responses, thereby enhancing user interaction, optimizing workflows, and maximizing the potential outcomes of AI chatbots.

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  • Österlund, Heléne
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Fältström, Emma
    Sweden Water Research, Lund, Sweden.
    μrban Plastics: Sources, sinks and flows of microplastics in the urban environment2023Report (Other academic)
    Abstract [en]

    Microplastics have been studied in marine and coastal waters since the early 1970’s. Several studies have reported that microplastics in the marine environment originate from land-based sources and is released with stormwater and wastewater. More attention is therefore placed on the urban water systems.

    This project has mapped pathways of microplastics from the terrestrial to the aquatic environment, with focus on urban stormwater. Some of the questions investigated were which type and what amount of microplastics is to be found in stormwater facilities, how is the most common plastic litter from streets broken down to microplastic particles, where in urban areas are microplastics found and how can the pollution be controlled?

    In a model city, the largest sources of microplastics in wastewater were laundry releasing synthetic fibers, while cigarette butts followed by paint and tire wear particles had the largest contributions to the stormwater. Tap water, roof runoff, and dust made small contributions. 

    The results from this report can be used to identify which plastics are present in different parts of the urban environment and will facilitate further efforts to identify the upstream pollution sources. The flow analysis gives an overview of the flows of microplastics on a city level and can be applied to other cities with different characteristics.

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  • Perez-Cerrolaza, Jon
    et al.
    Ikerlan Technology Research Centre, Basque Research and Technology Alliance (BRTA), Spain.
    Abella, Jaume
    Barcelona Supercomputing Center (BSC), Spain.
    Borg, Markus
    RISE Research Institutes of Sweden AB, Sweden.
    Donzella, Carlo
    Exida, Italy.
    Cerquides, Jesús
    Artificial Intelligence Research Institute (IIIA-CSIC), Spain.
    Cazorla, Francisco J.
    BSC and Maspatechnologies S.L., Spain.
    Englund, Cristofer
    RISE Research Institutes of Sweden AB, Sweden.
    Tauber, Markus
    Research Studios Austria, Austria.
    Nikolakopoulos, George
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Flores, Jose Luis
    Ikerlan Technology Research Centre, BRTA, Spain.
    Artificial Intelligence for Safety-Critical Systems in Industrial and Transportation Domains: A Survey2024In: ACM Computing Surveys, ISSN 0360-0300, E-ISSN 1557-7341, Vol. 56, no 7, article id 176Article in journal (Refereed)
    Abstract [en]

    Artificial Intelligence (AI) can enable the development of next-generation autonomous safety-critical systems in which Machine Learning (ML) algorithms learn optimized and safe solutions. AI can also support and assist human safety engineers in developing safety-critical systems. However, reconciling both cutting-edge and state-of-the-art AI technology with safety engineering processes and safety standards is an open challenge that must be addressed before AI can be fully embraced in safety-critical systems. Many works already address this challenge, resulting in a vast and fragmented literature. Focusing on the industrial and transportation domains, this survey structures and analyzes challenges, techniques, and methods for developing AI-based safety-critical systems, from traditional functional safety systems to autonomous systems. AI trustworthiness spans several dimensions, such as engineering, ethics and legal, and this survey focuses on the safety engineering dimension.

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  • Jayawickrama, Thamali Rajika
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Haugen, Nils Erland L.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. Department of Thermal Energy, SINTEF Energy Research, Kolbjørn Hejes vei 1 A, 7491 Trondheim, Norway.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. Technical University of Munich, Chair of Energy Systems, Boltzmannstr. 15, 85748 Garching b. München, Germany.
    On the inaccuracies of point-particle approach for char conversion modeling2024In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 370, article id 131743Article in journal (Refereed)
    Abstract [en]

    Char conversion is a complex phenomenon that involves not only heterogeneous reactions but also external and internal heat and mass transfer. Reactor-scale simulations often use a point-particle approach (PP approach) as sub-models for char conversion because of its low computational cost. Despite a number of simplifications involved in the PP approach, there are very few studies that systematically investigate the inaccuracies of the PP approach. This study aims to compare and identify when and why the PP approach deviates from resolved-particle simulations (RP approach). Simulations have been carried out for CO2 gasification of a char particle under zone II conditions (i.e., pore diffusion control) using both PP and RP approaches. Results showed significant deviations between the two approaches for the effectiveness factor, gas compositions, particle temperature, and particle diameter. The most significant sources of inaccuracies in the PP approach are negligence of the non-uniform temperature inside the particle and the inability to accurately model external heat transfer. Under the conditions with low effectiveness factors, the errors of intra-particle processes were dominant while the errors of external processes became dominant when effectiveness factors were close to unity. Because it assumes uniform internal temperature, the models applying the PP approach always predict higher effectiveness factors than the RP approach, despite its accurate estimation of intra-particle mass diffusion effects. As a consequence, the PP approach failed to predict the particle size changes accurately. Meanwhile, no conventional term for external heat transfer could explain the inaccuracy, indicating the importance of other sources of errors such as 2D/3D asymmetry or penetration of external flows inside the particles.

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  • Asghar, Raheel
    et al.
    College of Civil Engineering and Architecture, Shandong University of Science and Technology, 266590, Qingdao, China; Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus, 22060, Abbottabad, Pakistan.
    Javed, Muhammad Faisal
    Department of Civil Engineering, GIK Institute of Engineering Sciences and Technology, 23640, Swabi, Pakistan.
    Ali, Mujahid
    Department of Transport Systems, Traffic Engineering and Logistics, Faculty of Transport and Aviation Engineering, Silesian University of Technology, Krasińskiego 8 Street, 40-019, Katowice, Poland.
    Najeh, Taoufik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Gamil, Yaser
    Department of Civil Engineering, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500, Bandar Sunway, Selangor, Malaysia.
    Numerical and artificial intelligence based investigation on the development of design guidelines for pultruded GFRP RHS profiles subjected to web crippling2024In: Scientific Reports, E-ISSN 2045-2322, Vol. 14, article id 10135Article in journal (Refereed)
    Abstract [en]

    This article presents a numerical and artificial intelligence (AI) based investigation on the web crippling performance of pultruded glass fiber reinforced polymers’ (GFRP) rectangular hollow section (RHS) profiles subjected to interior-one-flange (IOF) loading conditions. To achieve the desired research objectives, a finite element based computational model was developed using one of the popular simulating software ABAQUS CAE. This model was then validated by utilizing the results reported in experimental investigation-based article of Chen and Wang. Once the finite element model was validated, an extensive parametric study was conducted to investigate the aforementioned phenomenon on the basis of which a comprehensive, universal, and coherent database was assembled. This database was then used to formulate the design guidelines for the web crippling design of pultruded GFRP RHS profiles by employing AI based gene expression programming (GEP). Based on the findings of numerical investigation, the web crippling capacity of abovementioned structural profiles subjected to IOF loading conditions was found to be directly related to that of section thickness and bearing length whereas inversely related to that of section width, section height, section’s corner radii, and profile length. On the basis of the findings of AI based investigation, the modified design rules proposed by this research were found to be accurately predicting the web crippling capacity of aforesaid structural profiles. This research is a significant contribution to the literature on the development of design guidelines for pultruded GFRP RHS profiles subjected to web crippling, however, there is still a lot to be done in this regard before getting to the ultimate conclusions.

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  • Riekkola, Jenni
    et al.
    Municipality of Luleå, Sweden.
    Isaksson, Gunilla
    Luleå University of Technology, Department of Health, Education and Technology, Health, Medicine and Rehabilitation.
    Lilja, Margareta
    Luleå University of Technology, Department of Health, Education and Technology, Health, Medicine and Rehabilitation.
    Rutberg, Stina
    Luleå University of Technology, Department of Health, Education and Technology, Health, Medicine and Rehabilitation.
    ‘Possibilities and challenges for older couples to continue ageing in place’2024In: Journal of Aging Studies, ISSN 0890-4065, E-ISSN 1879-193X, Vol. 69, article id 101229Article in journal (Refereed)
    Abstract [en]

    Ageing in place is an imminent concern for both older couples and communities. Identifying ways to support ageing in place is required to meet the needs and challenges of older couples and social services systems. Through focus groups with a total of 46 participants and a constant comparative methodology, this study aimed to explore and describe the experiences and reasoning of spousal carers, healthcare professionals, and stakeholders regarding possibilities for older couples to age in place. The findings consisted of one main category, ‘Facilitating ageing in place is a win-win situation with challenges’ and four interrelated categories, ‘Focus on older couples – building relationships and providing adequate services’, ‘Engaged civil society as a source of care and social inclusion,’ ‘Motivated professionals with competence and time,’ and ‘Services working together for a sustainable society,’ that present possibilities and challenges for ageing in place. This study suggests that facilitating ageing in place is possible but involves a complex series of challenges that can be linked to different contexts ranging from individuals and couples to civil society, services provided, organisational systems, and existing resources. All these aspects need to be considered and balanced to achieve a situation that contributes to older couples' possibilities to age in place as well as to a sustainable society.

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  • Johansson, Gunilla
    et al.
    Luleå University of Technology, Department of Health, Education and Technology, Nursing and Medical Technology.
    Johansson, Jeaneth
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Business Administration and Industrial Engineering. School of Business, Innovation and Sustainability, Halmstad University, Halmstad, Sweden.
    Engström, Åsa
    Luleå University of Technology, Department of Health, Education and Technology, Nursing and Medical Technology.
    Juuso, Päivi
    Luleå University of Technology, Department of Health, Education and Technology, Nursing and Medical Technology.
    Stakeholders’ perceptions of value of nature-based interventions in promoting health in people with stress-related illness: a qualitative study2024In: International Journal of Circumpolar Health, ISSN 1239-9736, E-ISSN 2242-3982, Vol. 83, no 1, article id 2349330Article in journal (Refereed)
    Abstract [en]

    Stress-related illness is a common and increasing cause for sick leave in Sweden. Spending time in nature reduces stress and promotes health and well-being. Accordingly, nature-based interventions (NBI) for people with stress-related illness have been developed and implemented in southern Scandinavia; however, such interventions are uncommon in the Circumpolar North. Previous studies have examined the effects and experiences of participating in NBI, but research about different stakeholders’ perspectives on NBI is lacking. The aim of this study was to explore different key stakeholders’ perceptions of the value of NBI in promoting health in people with stress-related illness. Data were collected through semi-structured interviews with 11 persons with stress-related illness experience, 14 healthcare professionals, and 11 entrepreneurs offering NBI. Qualitative content analysis resulted in four categories: Providing opportunity for recovery, Offering new perspectives and opportunity for reflection, Empowering balance and control in life, and Enabling one to overcome barriers. Although the study was conducted in a region where NBI is not widely implemented, the different stakeholders expressed similar perceptions of the value of NBI, indicating that NBI may be a valuable complement to health care which reaches people with stress-related illness needs and promotes their health. 

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  • Aronsson, Ingela
    et al.
    Department of Psychology, Umeå University, 901 87, Umeå, Sweden.
    Neely, Anna Stigsdotter
    Luleå University of Technology, Department of Health, Education and Technology, Health, Medicine and Rehabilitation. Department of Social and Psychological Studies, Karlstad University, Karlstad, Sweden.
    Boraxbekk, Carl-Johan
    Faculty of Medical and Health Sciences, Institute for Clinical Medicine, University of Copenhagen, Copenhagen, Denmark; Department of Diagnostics and Intervention, Diagnostic Radiology, and Umeå Center for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden; Institute of Sports Medicine Copenhagen (ISMC) and Department of Neurology, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark.
    Eskilsson, Therese
    Department of Public Health and Clinical Medicine, Section for Sustainable Health, Umeå University, Umeå, Sweden; Department of Community Medicine and Rehabilitation, Physiotherapy, Umeå University, Umeå, Sweden.
    Gavelin, Hanna M.
    Department of Psychology, Umeå University, 901 87, Umeå, Sweden; Department of Public Health and Clinical Medicine, Section for Sustainable Health, Umeå University, Umeå, Sweden.
    “Recovery activities are needed every step of the way”—exploring the process of long-term recovery in people previously diagnosed with exhaustion disorder2024In: BMC Psychology, E-ISSN 2050-7283, Vol. 12, article id 248Article in journal (Refereed)
    Abstract [en]

    Background: Sick-leave rates are high due to stress-related illnesses, but little is still known about the process of recovery from these conditions. The aim of this study was to explore the experiences of the recovery process, 6 to 10 years after treatment in people previously diagnosed with exhaustion disorder (ED), focusing on facilitators and barriers for the process of recovery from ED, and recovery activities experienced as helpful during the recovery process.

    Method: Thirty-eight participants (average age: 52 years, 32 females) previously diagnosed with ED were interviewed with semi-structured interviews 6–10 years after undergoing treatment. The interviews were analyzed with thematic analysis.

    Results: Three themes resulted from the analysis. The first theme, “A long and rocky road”, summarizes the fluctuating path to feeling better and emphasizes barriers and facilitators that affected the process of recovery, with a focus on external life events and the participants’ own behaviors. Facilitators were changing workplace, receiving support, a reduction in stressors, and changed behaviors. Barriers were a poor work environment, caregiver responsibilities, negative life events and lack of support. The second theme “Recovery activities are needed every step of the way” describes how both the need for recovery activities and the types of activities experienced as helpful changed during the recovery process, from low-effort recovery activities for long periods of time to shorter and more active recovery activities. Recovery activities were described as important for self-care but hard to prioritize in everyday life. The last theme, “Reorienting to a new place”, captures the struggle to cope with the remaining impact of ED, and how internal facilitators in terms of understanding and acceptance were important to reorient and adjust to a new way of functioning.

    Conclusions: Recovering from ED is a long and ongoing process where recovery activities are needed every step of the way. Our results highlight the importance of supporting personal recovery and long-term behavioral change, addressing individual stressors that may perpetuate the condition, and adjusting recovery activities according to where the person is in the recovery process.

    Trial registration: ClinicalTrials.gov: NCT0073772. Registered on March 8, 2017. This study was pre-registered on Open Science Framework (osf.io).

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  • Chiquito, Eric
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Monrat, Ahmed Afif
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Digitalized and Decentralized Open-Cry Auctioning: Key Properties, Solution Design, and Implementation2024In: IEEE Access, E-ISSN 2169-3536, Vol. 12, p. 64686-64700Article in journal (Refereed)
    Abstract [en]

    Open-cry electronic auctions have revolutionized the landscape of high-value transactions for buying and selling goods. Online platforms such as eBay and Tradera have popularized these auctions due to their global accessibility and convenience. However, these centralized auctioning platforms rely on trust in a central entity to manage and control the processing of bids, e.g., the submission time and validity. The use of blockchain technologies for constructing decentralized systems has gained popularity for their versatility and useful properties toward decentralization. However, blockchain-based open-cry auctions, are sensitive to the order of transactions and deadlines which, in the absence of a governing party, need to be provided in the system design. In this paper, we identify the key properties for the development of decentralized open-cry auctioning systems, including verifiability, transaction immutability, ordering, and time synchronization. Three prominent blockchain platforms, namely, Ethereum, Hyperledger Fabric, and R3 Corda were analyzed in terms of their capabilities to ensure these properties for gap identification. We propose a solution design that addresses these key properties and presents a proof-of-concept (PoC) implementation of such design. Our PoC uses Hyperledger Fabric and mitigates the identified gaps related to the time synchronization of this system by utilizing an external component. During the chaincode execution, the creation and submission of bids initiate requests to the time service API. This API service retrieves trusted timestamps from NTP services to obtain accurate bid times. We then analyzed the system design and implementation in the context of the identified key properties. Lastly, we conducted a performance evaluation of the time service and the PoC system implementation in time-sensitive scenarios and assessed its overall performance.

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  • Maurya, Himanshu Singh
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, 19086 Tallinn, Estonia.
    Juhani, K.
    Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, 19086 Tallinn, Estonia.
    Tarraste, M.
    Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, 19086 Tallinn, Estonia.
    Viljus, M.
    Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, 19086 Tallinn, Estonia.
    Sergejev, F.
    Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, 19086 Tallinn, Estonia.
    Pampori, T.H.
    Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, 19086 Tallinn, Estonia.
    Hussain, A.
    Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, 19086 Tallinn, Estonia.
    Kübarsepp, Jakob
    Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, 19086 Tallinn, Estonia.
    Synergistic effect of Nb and Mo on the microstructural formationof the Ti(C,n)-high chromium ferrous-based cermets2024In: International journal of refractory metals & hard materials, ISSN 0263-4368, article id 106723Article in journal (Refereed)
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  • Anjaneya Reddy, Yuvarajendra
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Wahl, Joel
    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.
    Experimental dataset investigation of deep recurrent optical flow learning for particle image velocimetry: flow past a circular cylinder2024In: Measurement science and technology, ISSN 0957-0233, E-ISSN 1361-6501, Vol. 35, no 8, article id 085402Article in journal (Refereed)
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  • Haque, Shamima
    et al.
    School of Management Studies, Techno Main Salt Lake, Kolkata, India.
    Panda, Debadrita
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Business Administration and Industrial Engineering.
    Ghosh, Arpita
    Management Department, Techno India Institute of Technology, Kolkata, India.
    Gamifying sustainability with self-efficacy: motivating green behaviours in large industrial firms2024In: International Journal of Organizational Analysis, ISSN 1934-8835, E-ISSN 1758-8561, Vol. 32, no 11, p. 74-93Article in journal (Refereed)
    Abstract [en]

    Purpose - This paper aims to capture the challenges faced by large industrial firms in implementing employee green behaviour. It uses the gamification-based Octalysis framework for identifying motivational drives and entwins it to self-efficacy theory seeking to motivate and engage the employees through game techniques.

    Design/methodology/approach - This paper uses qualitative approach where semi-structured interviews were conducted through snowball sampling technique with managers in senior positions in power sector holding significant decision-making authority. The interviews were transcribed and were analysed thematically.

    Findings - This study offers compelling evidence that industrial firms are grappling to inculcate pro-environmental behaviour largely losing on incentivising motivation. Gamification can provide an enjoyable framework balancing intrinsic and extrinsic motivational drives.

    Practical implications - This study offers a framework applicable to organisations across sectors, addressing challenges in implementing green behaviour by leveraging four phases of game mechanics. It tackles issues related to motivation and demand for incentives by striking a balance between intrinsic and extrinsic motivations.

    Originality/value - This research stands out by incorporating game mechanics, specifically designed through Octalysis, to boost self-efficacy and encourage green behaviour among employees. Furthermore, it is in harmony with Sustainable Development Goals and circular principles.

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  • Zuo, Zhida
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China.
    Lu, Xiaohua
    State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China; Suzhou Laboratory, Suzhou, China.
    Ji, Xiaoyan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Modeling self-diffusion coefficients of ionic liquids using ePC-SAFT and FVT combined with Einstein relation2024In: AIChE Journal, ISSN 0001-1541, E-ISSN 1547-5905, article id e18468Article in journal (Refereed)
    Abstract [en]

    The electrolyte perturbed-chain statistical associating fluids theory (ePC-SAFT) coupled with free volume theory (FVT) was combined with Einstein relation, that is, ePC-SAFT-FVT-E, to describe self-diffusion coefficients (SDCs) of ionic liquids (ILs). In modeling, ePC-SAFT was used to calculate density, while FVT parameters, determined from viscosity data, were utilized to calculate the summation of ionic SDCs through the Einstein relation with one parameter. Two strategies were employed to determine this parameter: fitting experimental data for each IL or estimating a universal parameter from van der Waals volume. Comparative analysis reveals good agreement with experimental data, with average absolute relative deviations (ARDs) of 8.14% (strategy 1) and 10.29% (strategy 2). Subsequently, cationic and anionic SDCs were reliably determined from the summation of ionic SDCs, with average ARDs of 10.80% and 10.21%, respectively. This study indicates the ePC-SAFT-FVT-E model, employing viscosity-derived parameters and three universal parameters, reliably predicts SDCs of ILs in wide temperature and pressure ranges.

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  • Jampala, Annie Modestra
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Bajracharya, Suman
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Matsakas, Leonidas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Rova, Ulrika
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Christakopoulos, Paul
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Bioelectrochemical treatment of acid mine drainage: Microbiome synergy influences sulfidogenesis and acetogenesis2024In: Sustainable Chemistry for the Environment, E-ISSN 2949-8392, Vol. 6, article id 100106Article in journal (Refereed)
    Abstract [en]

    Bioelectrochemical systems (BES) are emerging as potential technologies that can remediate acid mine drainage (AMD) by cathodic reduction of sulfates to metal sulfides. This study evaluated bioelectrochemical remediation of sulfate rich AMD at two applied cathode potentials; BES-1: −1.0 V and BES-2: −0.8 V. Sulfate reducing bacteria were selectively enriched to be used as biocatalyst in BES. Initially, lactate was fed as carbon source and switched to chemolithoautotrophy with only CO2-fed conditions. Both BESs were operated at 3±0.2 g/l of sulfate with synthetic AMD (SAMD) fed first, and gradually changed to 50% AMD from mining site with 50% SAMD. Sulfate reduction was relatively higher with BES-1: 82% than BES-2: 76% coupled with sulfidogenesis. Interestingly, acetogenesis (BES-1: 2.12±0.2 g/l, BES-2: 1.9±0.2 g/l) was also noticed with high reduction currents (BES-1&2: >-70 mA). Microbiome community analysis revealed the dominant presence of sulfate reducers, acetogens, syntrophic bacteria and Methanobacterium, probing microbial synergy aiding sulfate reduction. An added advantage was the iron-sulfide (FeS) particles formation on cathode, which might have contributed to increased reduction currents. This study reveals insights into microbial synergy for autotrophic sulfate reduction within mixed microbiome communities along with the impact of FeS particles as conducive facilitator for electron transfer in BES, thereby enhancing electrosynthetic acetate production.

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  • Concina, Isabella
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    An Old Material for a New World: Prussian Blue and Its Analogues as Catalysts for Modern Needs2024In: Inorganics, E-ISSN 2304-6740, Vol. 12, no 4, article id 124Article, review/survey (Refereed)
    Abstract [en]

    Prussian blue analogues (PBAs) have recently emerged as effective materials in different functional applications, ranging from energy storage to electrochemical water splitting, thence to more “traditional” heterogeneous catalysis. Their versatility is due to their open framework, compositional variety, and fast and efficient internal charge exchange, coupled with a self-healing ability that makes them unique. This review paper presents and discusses the findings of the last decade in the field of the catalytic and photocatalytic application of PBAs in water remediation (via the degradation of organic pollutants and heavy metal removal) and the catalytic oxidation of organics and production or organic intermediates for industrial synthesis. Analysis of the catalytic processes is approached from a critical perspective, highlighting both the achievements of the research community and the limits still affecting this field.

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  • Enrichi, Francesco
    et al.
    Department of Engineering for Innovation Medicine, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy; ISP-CNR Institute of Polar Sciences - National Research Council, Via Torino 155, 30172, Mestre-Venice, Italy.
    Mastantuoni, Gabriella
    Division of Glycoscience, Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology, and Health, KTH Royal Institute of Technology, AlbaNova University Centre, 106 91, Stockholm, Sweden.
    Cassetta, Michele
    Department of Engineering for Innovation Medicine, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy; Department of Industrial Engineering, University of Trento, 38122, Trento, Italy.
    Sambugaro, Alessia
    Department of Engineering for Innovation Medicine, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy.
    Daldosso, Nicola
    Department of Engineering for Innovation Medicine, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy.
    Martucci, Alessandro
    Department of Industrial Engineering and INSTM, University of Padova, 35131, Padua, 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, Mestre-Venice, Italy.
    Cattaruzza, Elti
    Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Via Torino 155, 30172, Mestre-Venice, Italy.
    Righini, Giancarlo C.
    IFAC-CNR “Nello Carrara” Institute of Applied Physics – National Research Council, MiPLab, Via Madonna del Piano 10, 50019, Sesto Fiorentino, Italy.
    Structural and optical properties of Eu3+-doped sol–gel silica–soda glasses2024In: The European Physical Journal Plus, E-ISSN 2190-5444, Vol. 139, no 4, article id 346Article in journal (Refereed)
    Abstract [en]

    Rare earths (REs) incorporated in glasses, mostly in the form of RE3+ ions, have several applications such as lasers and optical amplifiers, spectral conversion layers for solar cells, light emitters and sensors. In this context, both the composition and the structural properties of the glass, as well as the dopant concentration play an important role in determining the optical properties and the efficiency of the system. Usually, the concentration of REs is small, below 1 at%, to avoid clustering and optical quenching. In this paper, we report the case of sol–gel Eu-doped silica–soda glass films. The addition of soda to silica can reduce RE clustering and precipitation, according to molecular dynamic simulations, but brings structural instabilities to the network. Here, sodium was varied from 10 to 30 at% and Eu from 0 to 8 at%. It was shown that Eu plays a significant role in the stabilization of the matrix, improving the transparency, the refractive index and the thickness of the films. The increase of Eu concentration provides a decrease of site symmetry and an increase of quantum efficiency (QY), reaching 71% for the highest 8 at% Eu doping, with remarkable absence of concentration quenching.

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  • Abkar, Mahdi Mohammed Abdullah
    et al.
    Faculty of Civil Engineering and Built Environment, Universiti Tun Hussein Onn Malaysia (UTHM) Parit Raja, Batu Pahat, Johor, Malaysia.
    Yunus, Riduan
    Faculty of Civil Engineering and Built Environment, Universiti Tun Hussein Onn Malaysia (UTHM) Parit Raja, Batu Pahat, Johor, Malaysia.
    Harouache, Ahmed
    Faculty of Technology Management & Business, Universiti Tun Hussein Onn Malaysia (UTHM) Parit Raja, Batu Pahat, Johor, Malaysia.
    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, Bandar Sunway, Selangor, Malaysia.
    Al-Shameri, Ahmed Saleh Ahmed Saif
    Faculty of Technology Management & Business, Universiti Tun Hussein Onn Malaysia (UTHM) Parit Raja, Batu Pahat, Johor, Malaysia.
    The adoption of automation technology for the mitigation of material waste on construction sites in the Malaysian construction industry2024In: International Journal of Construction Management, E-ISSN 1562-3599Article in journal (Refereed)
    Abstract [en]

    The construction business has always been at the forefront of technological advancements, and this trend has only accelerated in recent years as one of the important contexts among the other numerous new technologies. The current study aims to examine the relationship between Automation Technology Adoptions (ATA) and Construction Site Performance (CSP) and their influence on material waste mitigation measures in Johor construction sites. Data was gathered utilizing an online survey method, with the participants from the Johor construction industries representing contractors and experts. A total of 257 responses were valid to investigate the assumptions of the validations, and ‘Partial Lease Square - Structural Equation Modeling’ (PLS-SEM) procedure has been used. The adopted model may be used to help construction site managers and workers understand the importance of the ATA, CSP, and their utilization as material waste management approaches. The obtained results emphasize the relevance of automation technology adoption for mitigating construction material waste in construction sites with such a clear significance and clarity under the use of automation in construction sites. These findings will assist construction professionals to manage their materials on the job site and complete their projects.

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  • Joshi, Bhupendra
    et al.
    Department of Agricultural Engineering, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, 221005, India.
    Singh, Vijay Kumar
    Department of Soil and Water Conservation Engineering, Acharya Narendra Deva University of Agriculture & Technology, Kumarganj, Ayodhya, Uttar Pradesh, 224229, India View au.
    Vishwakarma, Dinesh Kumar
    Department of Irrigation and Drainage Engineering, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, 263145, India.
    Ghorbani, Mohammad Ali
    Department of Water Engineering, Faculty of Agriculture, University of Tabriz, Tabriz, 5166616471, Iran.
    Kim, Sungwon
    Department of Railroad Construction and Safety Engineering, Dongyang University, 36040, Yeongju, South Korea View author publications.
    Gupta, Shivam
    Department of Irrigation and Drainage Engineering, Acharya Narendra Deva University of Agriculture & Technology, Kumarganj, Ayodhya, Uttar Pradesh, 224229, India.
    Chandola, V. K.
    Department of Agricultural Engineering, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, 221005, India.
    Rajput, Jitendra
    Division of Agricultural Engineering, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
    Chung, Il-Moon
    Department of Water Resources and River Research, Korea Institute of Civil Engineering and Building Technology, Goyang-si, 10223, Republic of Korea.
    Yadav, Krishna Kumar
    Faculty of Science and Technology, Madhyanchal Professional University, Ratibad, Bhopal, 462044, India; Environmental and Atmospheric Sciences Research Group, Scientific Research Center, Al-Ayen University, Thi-Qar, Nasiriyah, 64001, Iraq.
    Mirzania, Ehsan
    Department of Water Engineering, Faculty of Agriculture, University of Tabriz, Tabriz, 5166616471, Iran.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Mattar, Mohamed A.
    Department of Agricultural Engineering, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh, 11451, Saudi Arabia.
    A comparative survey between cascade correlation neural network (CCNN) and feedforward neural network (FFNN) machine learning models for forecasting suspended sediment concentration2024In: Scientific Reports, E-ISSN 2045-2322, Vol. 14, article id 10638Article in journal (Refereed)
    Abstract [en]

    Suspended sediment concentration prediction is critical for the design of reservoirs, dams, rivers ecosystems, various operations of aquatic resource structure, environmental safety, and water management. In this study, two different machine models, namely the cascade correlation neural network (CCNN) and feedforward neural network (FFNN) were applied to predict daily-suspended sediment concentration (SSC) at Simga and Jondhara stations in Sheonath basin, India. Daily-suspended sediment concentration and discharge data from 2010 to 2015 were collected and used to develop the model to predict suspended sediment concentration. The developed models were evaluated using statistical indices like Nash and Sutcliffe efficiency coefficient (NES), root mean square error (RMSE), Willmott’s index of agreement (WI), and Legates–McCabe’s index (LM), supplemented by a scatter plot, density plots, histograms and Taylor diagram for graphical representation. The developed model was evaluated and compared with CCNN and FFNN. Nine input combinations were explored using different lag-times for discharge (Qt-n) and suspended sediment concentration (St-n) as input variables, with the current suspended sediment concentration as the desired output, to develop CCNN and FFNN models. The CCNN4 model with 4 lagged inputs (St-1, St-2, St-3, St-4) outperformed the other developed models with the lowest RMSE = 95.02 mg/l and the highest NES = 0.0.662, WI = 0.890 and LM = 0.668 for the Jondhara Station while the same CCNN4 model secure as the best with the lowest RMSE = 53.71 mg/l and the highest NES = 0.785, WI = 0.936 and LM = 0.788 for the Simga Station. The result shows the CCNN model was better than the FFNN model for predicting daily-suspended sediment at both stations in the Sheonath basin, India. Overall, CCNN showed better forecasting potential for suspended sediment concentration compared to FFNN at both stations, demonstrating their applicability for hydrological forecasting with complex relationships.

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  • Arora, Siddhant
    et al.
    School of Computer Science and Engineering (SCOPE), Vellore Institute of Technology, Chennai Campus, Vandalur Kelambakkam Road, Chennai 600127, India.
    Venkatesh, Sridharan Naveen
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Sugumaran, Vaithiyanathan
    School of Mechanical Engineering (SMEC), Vellore Institute of Technology, Chennai Campus, Vandalur Kelambakkam Road, Chennai 600127, India.
    Prabhakaranpillai Sreelatha, Anoop
    Sustainable Mobility Automobile Research Technology (SMART) Center, Department of Electronics and Communication Engineering, Amrita Vishwa Vidyapeetham, Amritapuri, India.
    Mahamuni, Vetri Selvi
    Department of Project Management, Mettu University, P.O. Box: 318, Metu, Ethiopia.
    Enhancing Tire Condition Monitoring through Weightless Neural Networks Using MEMS-Based Vibration Signals2024In: Journal of Engineering, ISSN 2314-4904, E-ISSN 2314-4912, article id 1321775Article in journal (Refereed)
    Abstract [en]

    Tire pressure monitoring system (TPMS) has a critical role in safeguarding vehicle safety by monitoring tire pressure levels. Keeping the accurate tire pressure is necessary for confirming comfortable driving and safety, and improving fuel consumption. Tire problems can result from various factors, such as road surface conditions, weather changes, and driving activities, emphasizing the importance of systematic tire checks. This study presents a novel method for tire condition monitoring using weightless neural networks (WNN), which mimic neural processes using random-access memory (RAM) components, supporting fast and precise training. Wilkes, Stonham, and Aleksander Recognition Device (WiSARD), a type of WNN, stands out for its capability in classification and pattern recognition, gaining from its ability to avoid repetitive training and residual formation. For vibration data acquisition from tires, cost-effective micro-electro-mechanical system (MEMS) sensors are employed, offering a more economical solution than piezoelectric sensors. This approach yields a variety of features, such as autoregressive moving average (ARMA), statistical and histogram features. The J48 decision tree algorithm plays a critical role in selecting essential features for classification, which are subsequently divided into training and testing sets, crucial for assessing the WiSARD classifier’s efficacy. Hyperparameter optimization of the WNN leads to improved classification accuracy and shorter computation times. In practical tests, the WiSARD classifier, when optimally configured, achieved an impressive 97.92% accuracy with histogram features in only 0.008 seconds, showcasing the capability of WNN to enhance tire technology and the accuracy and efficiency of tire monitoring and maintenance.

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  • Mishra, Abhay
    et al.
    Department of Biophysics, All India Institute of Medical Sciences, 110029, New Delhi, India.
    Zehra, Sadaqa
    Department of Biophysics, All India Institute of Medical Sciences, 110029, New Delhi, India.
    Bharti, Prahalad Kumar
    Department of Biophysics, All India Institute of Medical Sciences, 110029, New Delhi, India.
    Mathur, Sandeep R.
    Department of Pathology, All India Institute of Medical Sciences, 110029, New Delhi, India.
    Ranjan, Piyush
    Department of Surgical Disciplines, All India Institute of Medical Sciences, 110029, New Delhi, India.
    Batra, Atul
    Department of Medical Oncology, All India Institute of Medical Sciences, 110029, New Delhi, India.
    Inampudi, Krishna K.
    Department of Biophysics, All India Institute of Medical Sciences, 110029, New Delhi, India.
    Modi, Gyan Prakash
    Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (BHU), 221005, Varanasi, Uttar Pradesh, India.
    Nikolajeff, Fredrik
    Luleå University of Technology, Department of Health, Education and Technology, Nursing and Medical Technology.
    Kumar, Saroj
    Luleå University of Technology, Department of Health, Education and Technology, Nursing and Medical Technology. Department of Biophysics, All India Institute of Medical Sciences, 110029, New Delhi, India.
    Spectroscopic insight into breast cancer: profiling small extracellular vesicles lipids via infrared spectroscopy for diagnostic precision2024In: Scientific Reports, E-ISSN 2045-2322, Vol. 14, article id 9347Article in journal (Refereed)
    Abstract [en]

    Breast cancer, a leading cause of female mortality due to delayed detection owing to asymptomatic nature and limited early diagnostic tools, was investigated using a multi-modal approach. Plasma-derived small EVs from breast cancer patients (BrCa, n = 74) and healthy controls (HC, n = 30) were analyzed. Small EVs (n = 104), isolated through chemical precipitation, underwent characterization via transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). Validation involved antibody-based tests (TSG101, CD9, CD81, CD63). Infrared spectra of small EVs were obtained, revealing significant differences in lipid acyl chains, particularly in the C–H stretching of CH3. The study focused on the lipid region (3050–2900 cm−1), identifying peaks (3015 cm−1, 2960 cm−1, 2929 cm−1) as distinctive lipid characteristics. Spectroscopic lipid-to-lipid ratios [(I3015/I2929), (I2960/I2929)] emerged as prominent breast cancer markers. Exploration of protein, nucleic acid, and carbohydrate ratios indicated variations in alpha helices, asymmetric C–H stretching vibrations, and C–O stretching at 1033 cm−1. Principal component analysis (PCA) successfully differentiated BrCa and HC small EVs, and heatmap analysis and receiver operating characteristic (ROC) curve evaluations underscored the discriminatory power of lipid ratios. Notably, (I2960/I2929) exhibited 100% sensitivity and specificity, highlighting its potential as a robust BrCa sEV marker for breast cancer detection.

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  • Bawankar, Nilesh
    et al.
    International Institute of Information Technology (IIIT-H), Hyderabad, Telangana, India.
    Kriti, Ankit
    International Institute of Information Technology (IIIT-H), Hyderabad, Telangana, India.
    Chouhan, Shailesh Singh
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Chaudhari, Sachin
    International Institute of Information Technology (IIIT-H), Hyderabad, Telangana, India.
    IoT-enabled Water Monitoring in Smart Cities with Retrofit and Solar-based Energy Harvesting2024In: IEEE Access, E-ISSN 2169-3536, Vol. 12, p. 58222-58238Article in journal (Refereed)
    Abstract [en]

    Monitoring water flow helps to identify leaks and wastage, leading to better management of water resources and conservation of this precious resource. To address this challenge, there is a need for an efficient and sustainable water management system. This paper presents an Internet of Things (IoT) based solution that involves retrofitting existing analog water meters using readily available off-the-shelf electronic components. Real-time data collection and analysis are performed through edge computation, which locally processes water meter images captured by the camera and extracts water meter readings. These readings are transmitted to the cloud for storage and further analysis. Various strategies have been implemented to optimize supply-current usage, preserving charge-discharge cycles of solar-powered batteries even in adverse environmental conditions. To streamline the firmware update process for multiple connected devices, a broadcasting technique is employed, offering the benefits of reduced manual labor and time savings. To assess the reliability and performance of developed solution, field deployment is conducted over several months, enabling the characterization of water usage patterns across different locations. Integrating energy harvesting capabilities into system reduces maintenance costs and promotes eco-friendly energy practices. Overall, this solution offers an effective and comprehensive approach towards achieving efficient and sustainable water management.

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  • Zapata Tamayo, Juan Guillermo
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Machine Elements. Royal Institute of Technology KTH, Department of Engineering Design, Stockholm 100 44, Sweden.
    Björling, Marcus
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Machine Elements. Division of Machine Elements, Department of Engineering Sciences and .
    Shi, Yijun
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Machine Elements.
    Hardell, Jens
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Machine Elements.
    Larsson, Roland
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Machine Elements.
    Micropitting performance and friction behaviour of DLC coated bearing steel surfaces : On the influence of Glycerol-based lubricants2024In: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 196, article id 109674Article in journal (Refereed)
    Abstract [en]

    A better understanding about the rolling contact fatigue and micropitting performance of machine component surfaces lubricated with environmentally friendly lubricants is critical to designing and further formulating new lubricants intended to be used in rolling–sliding contacts such as those found in gear and bearing applications. In this work, the frictional behaviour and rolling contact fatigue (RCF) performance of DLC, Cr/a-WC:H/a-C:H and a-C:Cr coatings under glycerol-based lubrication in rolling sliding contact conditions have been investigated. Traction maps, Stribeck curves, and fatigue plots have been generated by using a micropitting test rig (MPR). The initiation and progression of micropitting was monitored by means of white light optical interferometry and scanning electron microscopy (SEM). Results indicated that glycerol-based lubricants exhibited a significant friction reduction as the hydrodynamic effect is enhanced at higher rolling-speeds. Under boundary lubrication the friction coefficient was significantly higher compared to the values obtained with a commercial mineral-based transmission oil. Compared to uncoated steel surfaces, DLC coatings effectively reduced the volume loss and micropitting progression. Irrespective of the coating thickness, DLC showed an excellent tribological behaviour when the base lubricant favours the onset of mild-wear, over micropitting. When the lubricant formulation favoured the onset of micropitting, the coatings tended to prematurely fail due to debonding from the substrate, and local micro-spallation. The experiments demonstrated that friction reduction does not necessarily correspond with a reduction of micropitting.

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  • Rebeggiani, Sabina
    et al.
    Halmstad University, Sweden.
    Reddy, Vijeth
    Halmstad University, Sweden.
    Olofsson, Linus
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Fredriksson, Magnus
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Towards In-Line Measurements of Sawn Wood Surfaces2024In: Sustainable Production through Advanced Manufacturing, Intelligent Automation and Work Integrated Learning: Proceedings of the 11th Swedish Production Symposium (SPS2024) / [ed] Joel Andersson; Shrikant Joshi; Lennart Malmsköld; Fabian Hanning, IOS Press, 2024, p. 15-26Conference paper (Refereed)
    Abstract [en]

    Metrology and characterisation of products' functional surfaces are of key importance in smart and sustainable manufacturing. By proper measures of resulting topography and dimension at the micro-cm level, higher process control can be achieved, leading to more efficient production with products closer to defined targets. Commercial surface metrology systems for lab- and in/on-line applications have increased in the last decades, but the wood sector has not yet benefited from this development. A better understanding of sawn wood topography combined with smart online metrology systems is expected to lead to a substantial reduction of waste in sawmill production, both by transforming waste pieces and sideboards into engineered wood products and by optimising the sawing process (e.g. by using thinner saw blades and reduced tolerances). It would also open new design possibilities and challenge the construction sector to replace today’s materials with renewable raw materials. Additionally, sawmills will be less dependent on incoming timber dimensions. This study is the first step towards a better understanding of sawn wood topography and how relevant surface features can be detected and analysed to enable the next generation of functional wood surfaces for various applications. By identifying the measuring instrument’s capability to capture surface topographical features of sawn wood, this paper discusses the requirements for efficient measurement techniques. It opens for future implementation of machine learning algorithms to in-line monitor and control the machining process. All tested metrology techniques showed promising results. To capture machining marks, the instrumentation needs to have lateral resolutions on the um level and a measurement area covering some cm; thus, the laser scanning system seemed to be a good compromise.

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  • Ye, Nannan
    et al.
    State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China.
    Shen, Yusi
    State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China.
    Chen, Yifeng
    CAF, Key and Open Laboratory of Forest Chemical Engineering, Key Laboratory of Biomass Energy and Material, SFA, National Engineering Laboratory for Biomass Chemical Utilization, Institute of Chemical Industry of Forest Products, Nanjing 210042, P. R. China.
    Cao, Jian
    State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China.
    Lu, Xiaohua
    State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, P. R. China; Suzhou Laboratory, Suzhou 215100, P. R. China.
    Ji, Xiaoyan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Enhanced CO2 Capture through SAPO-34 Impregnated with Ionic Liquid2024In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 40, no 17, p. 9097-9107Article in journal (Refereed)
    Abstract [en]

    The concurrent utilization of an adsorbent and absorbent for carbon dioxide (CO2) adsorption with synergistic effects presents a promising technique for CO2 capture. Here, 1-butyl-3-methylimidazole acetate ([Bmim][Ac]), with a high affinity for CO2, and the molecular sieve SAPO-34 were selected. The impregnation method was used to composite the hybrid samples of [Bmim][Ac]/SAPO-34, and the pore structure and surface property of prepared samples were characterized. The quantity and kinetics of the sorbed CO2 for loaded samples were measured using thermogravimetric analysis. The study revealed that SAPO-34 could retain its pristine structure after [Bmim][Ac] loading. The CO2 uptake of the loaded sample was 1.879 mmol g-1 at 303 K and 1 bar, exhibiting a 20.6% rise compared to that of the pristine SAPO-34 recording 1.558 mmol g-1. The CO2 uptake kinetics of the loaded samples were also accelerated, and the apparent mass transfer resistance for CO2 sorption was significantly reduced by 11.2% compared with that of the pure [Bmim][Ac]. The differential scanning calorimetry method revealed that the loaded sample had a lower CO2 desorption heat than that of the pure [Bmim][Ac], and the CO2 desorption heat of the loaded samples was between 30.6 and 40.8 kJ mol-1. The samples exhibited good cyclic stability. This material displays great potential for CO2 capture applications, facilitating the reduction of greenhouse gas emissions.

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  • Elnourani, Mohamed
    et al.
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Humans and Technology.
    Johansen, Kerstin
    School of Engineering, Jönköping University, 551 11 Jönköping, Sweden.
    Rönnbäck, Anna Öhrwall
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Humans and Technology.
    Enabling Factors for Circularity in the Metal Cutting Industry - With Focus on High-Value Circular Tools2024In: Sustainable Production through Advanced Manufacturing, Intelligent Automation and Work Integrated Learning: Proceedings of the 11th Swedish Production Symposium (SPS2024) / [ed] Joel Andersson; Shrikant Joshi; Lennart Malmskold; Fabian Hanning, IOS Press, 2024, p. 502-519Conference paper (Refereed)
    Abstract [en]

    Metal cutting industry, a key sector in manufacturing, is grappling with the transition to a "net-zero industry" to mitigate climate change and reach sustainable practices. Rare and exclusive materials make recycling and reusing cutting tools more pressing and necessitate efficient circular material flows. The purpose of this research is to explore how collaboration can facilitate circularity in the cutting tool industry. It examines the involvement of stakeholders and their roles in achieving a circular lifecycle for cutting tools. To investigate the interaction between metal cutting tools suppliers and Small and Medium-sized Enterprises (SMEs), this study used a mixed-methods approach that includes data from literature, interviews, and document study. Empirical data is gathered to investigate the factors driving circularity and to identify important participants in the lifecycle of cutting tools. The study revealed challenges to the current situation including underutilization of tools due to the absence of a standardization process and subjective operator judgment, as well as lack of traceability of the tools both internally at SMEs and between the stakeholders. Moreover, by mapping the current actors, the study found cutting tool traceability, undirected decision-making throughout tool lifecycles, and limited awareness of circularity dimensions are key challenges. To handle these challenges. 9Rs circular economy framework used to investigate the possible role of collaboration emerges as a vital enabler for circularity, with SMEs playing a significant role. Moreover, the involvement of machine operators, often overlooked actors, is found to be crucial in influencing circular outcomes. Digital solutions and collaborative strategies that involve CNC machine suppliers and intermittent refurbishing business are pivotal in overcoming the challenges identified, namely, traceability and human subjectivity in tool condition assessment. The study demonstrates that technology providers, intermediary refurbishing businesses, SMEs and other stakeholders operating in the metal cutting tools sector must be involved throughout their lifetime to avoid suboptimal results, exchange information, and inspire industrial actors to support the circular economy.

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  • Gangwani, Prashant
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Machine Elements. Laboratory for Tribology and Interface Nanotechnology, University of Ljubljana, Ljubljana, 1000, Slovenia.
    Kovač, Janez
    Department of Surface Engineering, Jožef Stefan Institute, Ljubljana, 1000, Slovenia.
    Emami, Nazanin
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Machine Elements.
    Kalin, Mitjan
    Laboratory for Tribology and Interface Nanotechnology, University of Ljubljana, Ljubljana, 1000, Slovenia.
    Effect of multi-scale fillers on the tribological behavior of UHMWPE composites in water-lubricated contacts2024In: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 196, article id 109669Article in journal (Refereed)
    Abstract [en]

    This study investigates the impact of graphite, hexagonal boron nitride and short carbon fibers, acting as micro- and nano-fillers, on the tribological performance of ultra-high-molecular-weight polyethylene (UHMWPE) hybrid composites. The tribological performance is evaluated under boundary-lubrication conditions with distilled water at contact pressures in the range from 5 and 15 MPa. The fillers were found to work synergistically, with the best performance recorded when the compositions incorporated fillers of all scales. The most effective composite, consisting of short carbon fibers, micro-scale graphite, micro-scale hBN and nano-scale hBN, reduced the coefficient of friction by 75 %, reaching a value of 0.06, and the specific wear rate by two orders of magnitude to 2 × 10−7 mm3/Nm, compared to pure UHMWPE. The fillers' size also played an important role. Composites with nano-boron nitride led to 40 % lower friction compared to micro-scale fillers only. However, all the fillers reduced the amount of abrasive wear, especially the boron nitride, as a consequence of the tribochemical reaction between the boron nitride and water at the interface. Additionally, the formation of a transfer film was observed on the steel discs, with only short carbon fibers and graphite contributing to its formation from among the fillers used.

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  • Volpp, Joerg
    Drop Detachment Under Intense Laser Irradiation2024In: Sustainable Production through Advanced Manufacturing, Intelligent Automation and Work Integrated Learning: Proceedings of the 11th Swedish Production Symposium (SPS2024) / [ed] Joel Andersson; Shrikant Joshi; Lennart Malmskold; Fabian Hanning, IOS Press, 2024, p. 62-68Conference paper (Refereed)
    Abstract [en]

    During laser processing, complex effects can occur regarding the laser-material interactions. A high laser energy input leads to surface melting and even boiling. The resulting recoil pressure can create the so-called keyhole, a vapor channel existing during welding and called cut front during laser cutting. On the keyhole front wall, the induced recoil pressure pushes the melt downwards and can ejects melt drops. Usually, those melt ejections are seen as undesired spattering or necessary waste to enable the cutting. However, outflow characteristics can tell more about the complex process behavior. Therefore, this work aimed to relate melt ejection formation effects to keyhole behavior in order to get a better understanding of the complex laser-matter-interactions and fluid flows. Axial beam shaping was used to create different energy inputs into the keyhole front walls. Beam shaping was done with an optic that can superposition up to four laser beams in axial direction, leading to varying intensity distributions on the inclined keyhole front walls. Based on high-speed image analysis, it was seen that different outflow characteristics occur depending on the beam shapes. A high intensity on the front keyhole wall could be related to high temperatures on the keyhole wall. The outflow mechanism was shown to be able to move from corrugating to atomizing drop generation at increasing temperature due to temperature-dependent material properties. The main influencing factors are assumed to be the vapor speed and the keyhole/drop diameters that define the outflow mechanism.

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  • McCormick, Stephen
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Fill-ins with scalar curvature lower bounds and applications to positive mass theorems2024In: Annals of Global Analysis and Geometry, ISSN 0232-704X, E-ISSN 1572-9060, Vol. 65, no 4, article id 26Article in journal (Refereed)
    Abstract [en]

    Given a constant C and a smooth closed (𝑛−1)-dimensional Riemannian manifold (Σ,𝑔) equipped with a positive function H, a natural question to ask is whether this manifold can be realised as the boundary of a smooth n-dimensional Riemannian manifold with scalar curvature bounded below by C and boundary mean curvature H. That is, does there exist a fill-in of (Σ,𝑔,𝐻) with scalar curvature bounded below by C? We use variations of an argument due to Miao and the author (Int Math Res Not 7:2019, 2019) to explicitly construct fill-ins with different scalar curvature lower bounds, where we permit the fill-in to contain another boundary component provided it is a minimal surface. Our main focus is to illustrate the applications of such fill-ins to geometric inequalities in the context of general relativity. By filling in a manifold beyond a boundary, one is able to obtain lower bounds on the mass in terms of the boundary geometry through positive mass theorems and Penrose inequalities. We consider fill-ins with both positive and negative scalar curvature lower bounds, which from the perspective of general relativity corresponds to the sign of the cosmological constant, as well as a fill-in suitable for the inclusion of electric charge.

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  • Abrahamson, Josefin
    et al.
    Orthopaedic Research Unit, Sahlgrenska University Hospital, Sahlgrenska University Hospital, R-huset, Plan 7, 41380 Mölndal, Gothenburg, Sweden; Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Box 100, 405 30 Gothenburg, Gothenburg, Sweden.
    Lindman, Ida
    Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Box 100, 405 30 Gothenburg, Gothenburg, Sweden.
    Jónasson, Pall
    Department of Orthopaedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Box 100, 405 30 Gothenburg, Gothenburg, Sweden.
    Tegner, Yelverton
    Luleå University of Technology, Department of Health, Education and Technology, Health, Medicine and Rehabilitation.
    High prevalence of former elite ice hockey players requiring early hip arthroplasty surgery2024In: Journal of Hip Preservation Surgery (JHPS), ISSN 2054-8397Article in journal (Refereed)
    Abstract [en]

    The high-impact nature of ice hockey puts the players at a higher risk of developing early hip osteoarthritis (OA). This study aims to evaluate the presence of cam morphology, early radiological findings of OA and total hip arthroplasty (THA) in former Swedish elite ice hockey players. Male elite ice hockey players in the highest league in Sweden seeking orthopedic consultation for hip and groin pain with restricted hip joint range of motion and subsequent radiographs (Antero/posterior view, Lauenstein view and/or Hip frontal view) were included. The radiographs were performed between 1988 and 2009 and retrospectively examined for the presence of cam morphology (evaluated by alpha-angle >= 60 degrees) and hip OA (evaluated by Tonnis classification). All players were contacted between 11 and 33 years after baseline radiograph examination for follow-up investigation of the presence of subsequent THA. A total of 44 male ice hockey players were included, of which 31 had available radiographs and 39 answered the follow-up questions. Cam morphology (alpha-angle >= 60 degrees) was present in 81% of the players. Seven players (18%) had received a THA with a mean age of 55.7 (SD 6.1) years at time of THA-surgery. Tonnis score at baseline radiographs were associated with THA later in life (P < 0.001). This study conclude that former elite Swedish ice hockey players underwent THA at a younger age than the general population. Despite confirming previous research of high prevalence of cam morphology in elite ice hockey players, no association could be established between cam morphology and the need for THA.

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  • Bank, Michael S.
    et al.
    Institute of Marine Research, Bergen, Norway; University of Massachusetts Amherst, Amherst, MA, USA.
    Ho, Quang Tri
    Institute of Marine Research, Bergen, Norway.
    Kutti, Tina
    Institute of Marine Research, Bergen, Norway.
    Kögel, Tanja
    Institute of Marine Research, Bergen, Norway.
    Rodushkin, Ilia
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering. ALS Scandinavia AB, SE-971 87 Luleå, Sweden.
    van der Meeren, Terje
    Institute of Marine Research, Bergen, Norway.
    Wiech, Martin
    Institute of Marine Research, Bergen, Norway.
    Rastrick, Samuel
    Institute of Marine Research, Bergen, Norway.
    Multi-isotopic composition of brown crab (Cancer pagurus) and seafloor sediment from a mine tailing sea disposal impacted fjord ecosystem2024In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 471, article id 134406Article in journal (Refereed)
    Abstract [en]

    Here we studied accumulation of heavy metals in brown crab (Cancer pagurus) and seafloor sediment from Jøssingfjord, Norway during 2018 to evaluate long-term, legacy pollution effects of coastal mine tailing sea disposal activities. Nickel and copper sediment pollution in the mine tailing sea disposal area was classified as moderate and severe, respectively, under Norwegian environmental quality standards, and highlights the persistent hazard and legacy impacts of heavy metals in these impacted fjord ecosystems. Mercury, zinc, and arsenic had stronger affinities to brown crab muscle likely due to the presence of thiols, and availability of metal binding sites. Our multi-isotopic composition data showed that lead isotopes were the most useful source apportionment tool for this fjord. Overall, our study highlights the importance and value of measuring several different heavy metals and multiple isotopic signatures in different crab organs and seafloor sediment to comprehensively evaluate fjord pollution and kinetic uptake dynamics. Brown crabs were suitable eco-indicators of benthic ecosystem heavy metal pollution in a fjord ecosystem still experiencing short- and long-term physical and chemical impacts from coastal mining sea disposal activities.

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  • Sörman, Daniel Eriksson
    et al.
    Luleå University of Technology, Department of Health, Education and Technology, Health, Medicine and Rehabilitation. Department of Psychology, Umeå University, Umeå, Sweden.
    Åstrom, Elisabeth
    Department of Psychology, Umeå University, Umeå, Sweden.
    Ahlström, Mikael
    Luleå University of Technology, Department of Health, Education and Technology, Health, Medicine and Rehabilitation.
    Adolfsson, Rolf
    Department of Clinical Science, Umeå University, Umeå, Sweden.
    Körning Ljungberg, Jessica
    Luleå University of Technology, Department of Health, Education and Technology, Health, Medicine and Rehabilitation.
    The influence of personality traits on engagement in lifelong learning2024In: International Journal of Lifelong Education, ISSN 0260-1370, E-ISSN 1464-519XArticle in journal (Refereed)
    Abstract [en]

    Today, adult individuals must be able to continuously learn and adapt to the rapid changes occurring in society. However, little is known about the individual characteristics, particularly personality traits, that make adults more likely to engage in learning activities. Moreover, few studies have longitudinally and objectively investigated the influence of personality on engagement in lifelong learning throughout working age. This study therefore used longitudinal data (15 years) to examine which personality traits predicted level and long-term changes in learning activities among 1329 Swedish adults aged 30-60. The results from growth curve modelling showed that over the follow-up period, novelty seeking and self-transcendence were both positively related to overall level of engagement in learning activities, although not to rate of change. Regarding specific activities, novelty seeking was related to higher levels of engagement in attending courses, taking on new education, and making occupational changes, while harm avoidance was negatively related to the likelihood of changing occupation. The results of this study underscore the importance of considering personality in relation to engagement in lifelong learning activities. Insights from this study can potentially increase the likelihood of finding methods to promote lifelong learning, which can be beneficial for educators, policymakers, and companies.

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  • Naeem, Rimsha
    et al.
    University of Vaasa, School of Management, PO Box 700, 65101, Vaasa, Finland.
    Kohtamäki, Marko
    University of Vaasa, School of Management, PO Box 700, 65101, Vaasa, Finland.
    Parida, Vinit
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Business Administration and Industrial Engineering.
    Artificial intelligence enabled product–service innovation: past achievements and future directions2024In: Review of Managerial Science, ISSN 1863-6683, E-ISSN 1863-6691Article in journal (Refereed)
    Abstract [en]

    This study intends to scrutinize the role of Artificial Intelligence (AI) in Product-Service Innovation (PSI). The literature on AI enabled PSI, other related innovation business models, product-service systems, and servitization has grown significantly since 2018; therefore, there is a need to structure the literature in a systematic manner and add to what has been studied thus far. Product-service innovation is used to represent the relevance of achieving innovation in business models dealing with innovation outcomes including artificial intelligence. This study used bibliographic coupling to analyze 159 articles emerging from the fields of computer sciences, engineering, social sciences, decision sciences, and management. This review depicts structures of the literature comprising five (5) clusters, namely, (1) technology adoption and transformational barriers, which depicts the barriers faced during the adoption of AI-enabled technologies and following transformation; (2) data-driven capabilities and innovation, which highlights the data-based capabilities supported through AI and innovation; (3) digitally enabled business model innovation, which explained how AI-enabled business model innovation occurs; (4) smart design changes and sustainability, which reveals the working of AI in product service environments with different design changes and transformations based on sustainability; and (5) sectorial application, which highlights industry examples. Each cluster is comprehensively analyzed based on its contents, including central themes, models, theories, and methodologies, which help to identify the gaps and support suggestions for future research directions.

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  • Kroner, Désirée
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. Energy Engineering, School of Information and Engineering, Dalarna University, Falun, 79188, Sweden.
    Lundgren, Urban
    Wireless Communication, RISE Research Institute of Sweden, Box 857, Borås, 50115, Sweden.
    Augusto, André
    Energy Engineering, School of Information and Engineering, Dalarna University, Falun, 79188, Sweden.
    Bollen, Math
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Radiated Electromagnetic Emission from Photovoltaic Systems—Measurement Results: Inverters and Modules2024In: Energies, E-ISSN 1996-1073, Vol. 17, no 8, article id 1893Article in journal (Refereed)
    Abstract [en]

    Radiated electromagnetic emission of photovoltaic systems, for example, adversely impacting radiocommunication, can pose a major barrier against further increase in photovoltaic penetration. This is particularly the case near sensitive infrastructure and activities such as hospitals, airports, search and rescue, and military. To understand the impact of each component and installation detail, we performed systematic radiated electromagnetic emission measurements on comparable commercial photovoltaic systems in the frequency range 150 kHz to 30 MHz. Our measurements indicate that string inverters are unlikely to interfere with radiocommunication when installed according to recommended standards, rules, guidelines, and regulations. It was shown that module-level power optimizers are the main cause of high levels of radiated emissions. The frameless bifacial module showed higher levels of radiated emissions than the monofacial module with frame. Changes in cable management and earthing have less impact on radiated emissions than the choice of solar inverter concept and module type.

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  • Li, Sichao
    et al.
    Division of Surface and Corrosion Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden.
    Hammond, Oliver S.
    Department of Materials and Environmental Chemistry, Stockholm University, Stockholm SE-114 18, Sweden; intelligent Advanced Materials, Department of Biological & Chemical Engineering and iNANO, Aarhus University, Aarhus C 8000, Denmark.
    Nelson, Andrew
    Australian Centre for Neutron Scattering, ANSTO, Lucas Heights, New South Wales 2234, Australia.
    de Campo, Liliana
    Australian Centre for Neutron Scattering, ANSTO, Lucas Heights, New South Wales 2234, Australia.
    Moir, Michael
    National Deuteration Facility, ANSTO, Lucas Heights, New South Wales 2234, Australia.
    Recsei, Carl
    National Deuteration Facility, ANSTO, Lucas Heights, New South Wales 2234, Australia.
    Shimpi, Manishkumar R.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering. Department of Materials and Environmental Chemistry, Stockholm University, Stockholm SE-114 18, Sweden.
    Glavatskih, Sergei
    System and Component Design, Department of Engineering Design, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden; School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia; Department of Electromechanical, Systems and Metal Engineering, Ghent University, Ghent B-9052, Belgium.
    Pilkington, Georgia A.
    Division of Surface and Corrosion Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden.
    Mudring, Anja-Verena
    Department of Materials and Environmental Chemistry, Stockholm University, Stockholm SE-114 18, Sweden; intelligent Advanced Materials, Department of Biological & Chemical Engineering and iNANO, Aarhus University, Aarhus C 8000, Denmark; Department of Physics, Umeå University, Umeå SE-901 87, Sweden.
    Rutland, Mark W.
    Division of Surface and Corrosion Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden; School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia; Bioeconomy and Health Department Materials and Surface Design, RISE Research Institutes of Sweden, Stockholm SE-114 28, Sweden; Laboratoire de Tribologie et Dynamique des Systèmes, École Centrale de Lyon, Ecully Cedex 69134, France.
    Anion Architecture Controls Structure and Electroresponsivity of Anhalogenous Ionic Liquids in a Sustainable Fluid2024In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 128, no 17, p. 4231-4242Article in journal (Refereed)
    Abstract [en]

    Three nonhalogenated ionic liquids (ILs) dissolved in 2-ethylhexyl laurate (2-EHL), a biodegradable oil, are investigated in terms of their bulk and electro-interfacial nanoscale structures using small-angle neutron scattering (SANS) and neutron reflectivity (NR). The ILs share the same trihexyl(tetradecyl)phosphonium ([P6,6,6,14]+) cation paired with different anions, bis(mandelato)borate ([BMB]−), bis(oxalato)borate ([BOB]−), and bis(salicylato)borate ([BScB]−). SANS shows a high aspect ratio tubular self-assembly structure characterized by an IL core of alternating cations and anions with a 2-EHL-rich shell or corona in the bulk, the geometry of which depends upon the anion structure and concentration. NR also reveals a solvent-rich interfacial corona layer. Their electro-responsive behavior, pertaining to the structuring and composition of the interfacial layers, is also influenced by the anion identity. [P6,6,6,14][BOB] exhibits distinct electroresponsiveness to applied potentials, suggesting an ion exchange behavior from cation-dominated to anion-rich. Conversely, [P6,6,6,14][BMB] and [P6,6,6,14][BScB] demonstrate minimal electroresponses across all studied potentials, related to their different dissociative and diffusive behavior. A mixed system is dominated by the least soluble IL but exhibits an increase in disorder. This work reveals the subtlety of anion architecture in tuning bulk and electro-interfacial properties, offering valuable molecular insights for deploying nonhalogenated ILs as additives in biodegradable lubricants and supercapacitors.

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  • Boyle, Bryan
    et al.
    Luleå University of Technology, Department of Health, Education and Technology, Health, Medicine and Rehabilitation. School of Clinical Therapies, University College Cork, Cork, Ireland.
    Arnedillo-Sanchez, Inmaculada
    nnovation & Research, Pure Health Group, Dubai, United Arab Emirates.
    Zahid, Aejaz
    School of Clinical Therapies, University College Cork, Cork, Ireland.
    Pennisi, Yvonne
    School of Computer Science and Statistics, Trinity College Dublin, Dublin, Ireland.
    The Arabic psychosocial impact of assistive devices scale: Development, translation, and evaluation2024In: Assistive technology, ISSN 1040-0435, E-ISSN 1949-3614Article in journal (Refereed)
    Abstract [en]

    This paper describes the development, translation, and early evaluation of the Arabic Psychosocial Impact of Assistive Devices Scale (AR-PIADS), an outcome measure instrument for the subjective impact of Assistive Technology on a person with a disabilities&apos; quality of life. Developing the AR = PIADS instrument involved forward and backward translation by two independent teams of bilingual, Arabic-English speakers (n = 5) and a quality and usability review by a panel of people with disabilities (n = 18). The emergent version was evaluated with a group of experienced Arabic-speaking Assistive Technology users (n = 67) for its psychometric properties. Initial results demonstrate a favorable comparison for 16 of the 26 questionnaire items with scores recorded for the original, English language version. Internal consistency, measured using Cronbach&apos;s alpha, yielded a range of 0.97-0.99 for AR-PIADS while the new instrument&apos;s reliability was assessed using an intraclass correlation coefficient resulting in scores within the range of 0.86-0.97 for the overall instrument. Despite these positive results however, the translation process did highlight a number of challenges with language and cultural interpretation of the translated instrument. This suggests that further work is warranted to explore its utility in service provision.

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