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  • Sjödin, Caroline
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Eriksson, Veronika
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    SMASK!: Mot matsvinn2019Independent thesis Basic level (degree of Bachelor of Fine Arts), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Did you know that one third of all the produced food gets thrown away? (Globalamalen, u.å). You might as well throw away the third grocery bag you purchased right away, because that is what you will do in the end. This phenomenon is called food waste, meaning the food that is thrown away unnecessarily. In Sweden, households account for the majority of the country's total food waste. According to the Swedish Environmental Protection Agency (2018), 1.3 million tonnes of food waste arose in Sweden in 2016, which corresponds to 129 kilos per person, of which one third is classified as pure food waste.

    The world faces a major challenge of dealing with the growing environmental crisis. If everyone lived like us in Sweden, we would need four planets to be able to supply the whole world with natural resources (WWF, 2018). We need to change our consumption behavior, because material consumption goes hand in hand with our ecological footprint. According to the Swedish Environmental Protection Agency (2018), food waste in Sweden accounts for 20-25 percent of the country's total climate impact. At the same time, approximately 870 million people in the world are estimated to be malnourished (Swedish Environmental Protection Agency, 2018).

    One contributing factor is the consumer's attitude towards food; we do not appreciate the food like we used to and we have forgotten where it comes from. Media and designers has a huge part in this phenomenon, who promote and encourage us to consume more and more. According to a study from Popia (2012), 76 percent of all purchasing decisions are made in the store; Therefore, as designers, we have an important role in the design of packaging, advertising and signs.

    Food waste is a major contributing factor to the environmental crisis, and we have therefore chosen to highlight this area. In our work we have chosen to explore the area of ​​food waste and see how we through graphic design can influence, illuminate and change behaviors and attitudes of consumers.

    We believe that as designers, we have a social responsibility in shaping the future. In this work, we will examine two issues: Is it possible to encourage consumers in a positive way to change their behavior towards food waste in the long term? How can design methods break consumer behavior and attitudes to achieve reduced food waste?

    Our work has resulted in a packaging concept called SMASK!, where we have applied behavioral design methods on graphic form. Our challenge is to change consumers behavior and create new ones through graphic design. A great initiative for a sustainable future. Our home, our country, our mission.

  • Sköld, Martin
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Employee perspective on communication and engagement: A case study in a manufacturing organisation2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Purpose

    The purpose of this study was to gain a deeper understanding of how supervisor-employee communication affects the employee engagement on the shop floor of manufacturing organisations. To achieve this purpose, the two below research objectives were developed:

    • To identify how supervisor-employee communication impacts employee engagement
    • To identify any barriers to supervisor-employee communication

    Method

    The study had a deductive, qualitative research approach as a conceptual framework was developed from literature and then verified with empirical data collected through semi-structured interviews. The research strategy was holistic and single case as all eight interviews were conducted with respondents from a single organisation. The interviewees were selected using a maximum variation, purposive sampling technique. Lastly, the collected data was analysed using a form of thematic analysis.

    Findings

    The main finding was that supervisor-employee communication was proven to have a significant impact on the employee engagement among the shop floor workers in the manufacturing organisation. In addition, supervisor-employee communication was proven to affect the employee engagement in a similar way that literature suggested. Furthermore, the findings supported the definition of employee engagement as a shared responsibility between the employee and the supervisor.

    Theoretical implications

    This study provided additional data to the existing literature on supervisor-employee communication and employee engagement while investigating the relationship between these two concepts in a new setting. Not only did this study contribute with rather unique data from the manufacturing industry, but it also adopted the employee perspective of the phenomenon. Previous research has predominantly consisted of studies with the perspective of management rather than the employees. Therefore, this study offers a foundation upon which further, both qualitative and quantitative research within this area can be conducted.

    Practical implications

    The main practical implication that this study has offered is highlighting the importance of supervisor-employee communication when it comes to generating and maintaining employee engagement on the shop floor of manufacturing organisations. The supervisor’s role and way of communicating has been identified as crucial for the employees’ level of engagement and this study has provided some guidance for supervisors in this matter.

  • Sroka, Angelica
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    The IKEA Industry way of ergonomic risk assessment: Development of a global standard for ergonomic risk assessment2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In 2018 IKEA Industry, the largest producer of wood-based furniture for IKEA customers presented their sustainability strategy for Financial Year 2025. In Health & Safety, they want to minimize ergonomic risks at their factories. To be able to understand what risks the factories contain, the first step is a common ergonomic risk assessment methodology. Because of a lack of knowledge in ergonomics at IKEA Industry, the responsibility was laid on this master thesis project.

    This project has with the help of interviews, surveys and observations found what needs the factories have in ergonomic risk assessment. A literature review also found things that the factories should have but haven´t asked for. Using benchmarking, several common methods used on the market has been summarized and analyzed by the requirements. Three methods, KIM, RAMP and HARM were chosen to be tested by the factories. In a user test, it was clear that KIM was easiest to use. HARM was eliminated because of the lack of evaluating lifting and pushing movements. To choose between KIM and RAMP they were evaluated in terms of the requirements. The results showed that KIM was the best method for IKEA Industry factories.

    At some places RAMP had good assessment methods. In order to not ignore these, they have been implemented into KIM to make it suit the factories even better. The result ended up in a document called Global standard of ergonomic risk assessment. The method is divided into three different methods depending on if you have lifting/ carrying work, pushing work or repetitive work. The results are then summarized in a chart that shows what needs to be investigated. This project has also with the help of the literature and the analysis of the factory, decided which roles that will participate in the assessment. The suggestions are manager, ergonomist and a production co-worker.

    With the help of this method, the factories will be able to understand what ergonomic risks they have. They will only need to evaluate the work tasks with the help of this method and will then be presented all high, medium or low ergonomic risks in the factories to minimize these before FY2025.

  • Lövgren Pouncette, Albin
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Nielsen, Edith
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Kundbaserat varumärkeskapital: En deskriptiv studie med syftet att undersöka hur generation Z värderar varumärkeskapitalet hos en konsumentprodukt2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the thesis was to investigate how generation Z values ​​the customer-based brand equity of a consumer product. Generation Z is an interesting generation to study since they have shown to differ in a variety of aspects from previous generations. To answer the purpose, a model has been constructed, which is based on previous research. The model consists of the components; brand awareness, brand associations/image, perceived quality and brand loyalty. Together the components form the cornerstones of the customer-based brand equity. Eight hypotheses were tested with the purpose of measuring the interrelationship between the components, and the relationship between the various components and the customer-based brand equity. Six of these eight hypotheses could be accepted. The result showed that the components brand association/image and brand loyalty have a positive impact on the customer-based brand equity, while brand awareness and perceived quality showed a non-significant result. The non-significant results were then further examined through t-test, with the purpose of trying to find possible reasons for the outcome. Moreover, the results showed that brand awareness has a positive correlation with both brand associations/image and perceived quality. Finally, the result showed that brand loyalty was positively correlated to both brand associations/image and perceived quality. For further research, it is proposed that a more comprehensive study consisting of more respondents from generation Z should be conducted. In addition, further research could be based on other consumer products and also examine whether there could be more or other components that should be considered when measuring customer-based brand equity.

  • Paez, Elin
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Vilken utrikespolitik för Donald Trump?: En ideologianalys2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Since Donald Trump took office there has been split opinions about which foreign policy is led by the President. From his candidacy to his first 2 years in office he has made remarks that can be categorized as falling within the theory of realism, liberalism and populism. This study has been based from the two classical IR-theories realism, liberalism and populism as an unconventional theory aside from IR-theory through an ideology analysis to make sense of which foreign policy is being driven by Trump. The study focuses on two cases: The Middle East and North Korea with security policy in focus. This particular ideology analysis has focused on Trump Twitter account, statements and interviews from news channels and official documents from the White House. This material has been analyzed through ideal types within the two IR-theories and the theory of populism. The results of this study show that Donald Trump falls in within the bounds of realism for the most part based on these cases two cases. But attention is paid to his populist tone and rhetoric and that there is no coherent foreign policy driven in these cases. This much to Trumps outrageous remarks on Twitter and to the media but most of all the contradiction between the president and his own administration.

  • Standar, Matilda
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Resecentrum i perifera lägen: Ett konceptförslag för resecentrum i Piteå kopplat till Norrbotniabanan2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    At present, a large part of the products from the north is transported on the main line through upper Norrland, which handles all railway transports through Norrland. The track does not meet today´s requirements for freight transport because of its curvy and hilly traction, its only track and the fact that it is located far from the coast where most industries are situated. In 2002, the investigation of a new coastal railway began, which can relieve the main line from freight traffic, but also promote passenger transport by dimidiated travel times and increased communication between the cities. The new railway was named Norrbotniabanan and is planned to pass through the larger cities along the coast. Piteå is the city that has the most possible route options and potential locations for the railway station. After a number of investigations, only two alternative tractions through Piteå remains, alternatives P1 and P2. In alternative P1, or the Coastal route, Norrbotniabanan is supposed to run parallel with E4. A travel center is planned to be located south of Lomtjärn and west of E4. In the other alternative P2, or the Central route, the track would pass through the center of Piteå where the travel center would be located also.

    The purpose of this work has been to investigate the potential of Lomtjärn Travel Center in the alternative coastal route of the Norrbotniabanan railway. The aim was to be able to specify which features that should be implemented to achieve the best design for the Lomtjärn Travel Center in its peripheral position, with regard to social and ecological sustainability, to promote passenger transport. In order to achieve the aim information was obtained by a literature study linked to the railway station's basic properties and importance to the city. Furthermore, a study was conducted of existing peripheral stations to gather inspiration and see how others had solved various functions connected to the station. A site analysis was also conducted where the travel centers location previously determined by the municipality was analyzed to find out if it really was the best location in the area. The above studies and analyzes resulted in a concept proposal for the design of the Lomtjärn Travel Center.

    Early on, accessibility proved to be one of the most important success of the location of a railway station. The passage over the railway tracks and E4 is seen as the most important accessibility action because it breaks the barrier created by E4 and creates access to the station from two directions. Other measures that contribute to increased accessibility are the division of the car and cycle parking lots to each side of E4 and the connection between the station and the grocery store at Backen. Another action that is connected to both accessibility and ecological sustainability is the transport between the station and the center, as it strengthens the connection between them at the same time as it is fossil-free.

    Good personal security is also seen as important. The decision to choose a raised glazed walkway as a passage instead of a tunnel under the ground is considered to be a positive action for the proposal. Another security action was to add a kiosk, this creates security by adding someone who can oversee the station. Other measures that increase security are the choice to keep the passage open and not add anything that obscures the visibility and the fact that the entire passage is a waiting room, because it allows excellent view of the tracks.

    A solution that does not have much to do with either social or ecological sustainability, but which is nevertheless believed to be significant for Piteå city is the height of the passage. The height enables it to appear from a longer distance and form a landmark in the northwest while forming an entrance to Piteå.

  • Steinholtz, Linus
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Digitalisering av kulturscenen: Interaktionen mellan kulturscenen och den teknikvana generationen2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Rapporten sammanfattar ett examensarbete inom produktutveckling för Högskoleingenjör Teknisk Design på Luleå Tekniska Universitet. Arbetet är utfört hos Osynlig AB i Sundsvall för kunden Scenkonst Västernorrland. Syftet med arbetet har varit att ta fram koncept kring hur Scenkonst Västernorrland kan nyttja den digitala utvecklingen på ett sådant sätt att de enklare kan nå ut till och interagera med den yngre och mer teknikvana generationen.

    Scenkonst Västernorrland är verksamma inom marknadsföring av kulturevenemang så som dans, film, teater och musik. Kulturscenen står inför en förändring i och med den digitala framfarten och Scenkonst Västernorrland är därför ute efter att hitta nya sätt att förmedla evenemang och atti nteragera med sina målgrupper.

    Under projektets start handlade det om att sätta sig in i hur Scenkonst Västernorrland arbetar med interaktionen med den teknikvana generationen idag, samt vilka olika typer av utmaningar som finns. Med detta som grund gjordes sedan en benchmarking för att se hur liknande branscher interagerar med sina målgrupper. Intervjuer med både målgruppen och företag som är verksamma inom kulturscenen gjordes för att säkerhetsställa att det som kulturscenen uppleversom ett behov faktiskt också är det.

    I den andra fasen av projektet sammanställdes all data från intervjuer, enkäter och benchmarking i en effektkarta. Detta för att få en enklare överblick över projektet och se till att alla beslut som tas alltid stämmer överens med användarnas behov. Effektkartan innehåller problemformulering och specifika behov för målgrupperna.

    Utifrån detta genererades ett antal idéer som sedan gallrades ut till tre mer konkreta koncept. Koncepten utvärderades i form av prototyper gjorda i Adobe XD, enklare 3D-ytmodelleringar och mer fysiska modeller. Koncepten testades därefter på användare och bearbetades sedan ytterligare. Två av dessa koncept togs sedan vidare för mer bearbetning och utvärdering med användare, dessa koncept var Applikation och Interaktiv Display. Slutligen utfördes ett konceptval där konceptet Applikation valdes ut för mer detaljerad bearbetning innan den slutliga presentationen för Osynlig AB och kunden Scenkonst Västernorrland.

    Med hjälp av det koncept som togs fram blir informationen mer tillgänglig för spridning, samt att informationen blir mer närvarande i målgruppernas dagliga informationsflöden. På så sätt kan Scenkonst Västernorrland lättare interagera med den yngre och mer teknikvana generationen.

    Samtidigt som projektet har handlat om att undersöka och tillfredsställa kundens och deras målgruppers behov så handlar det även om att nå upp till uppdragsgivarens förväntningar för att upprätthålla en bra kundrelation.

  • Sundström, Erik
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Control 4.0: Creating a vision for the future of industrial control rooms under Industry 4.02019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Today’s industries are facing what some may call a new industrial revolution. Technological developments are heading towards more internet-based system solutions. This movement is often referred to as Industry 4.0 and is said to have the potential for more flexible, autonomous productions capable of managing themselves. With new technologies, however, there is also a demand for new competences and qualification requirements on the workforce. Furthermore, industries of today often have problems with recruiting new competent employees, especially younger people. Industries looking to implement Industry 4.0 would therefore have to manage the education and development of existing employees while also attracting new employees.

    As part of a larger research project at Luleå University of Technology, this thesis project aims to describe how the control rooms in Swedish metallurgic industries will be affected by Industry 4.0. Furthermore, the project aims to describe what changes that are desirable for achieving a sustainable, effective and equal industry. To better achieve this goal, the project was done in collaboration with the metallurgic industry SSAB, specifically the steel production in Luleå. Through visits, interviews and observations at the control rooms in SSAB’s steel production, the context of today’s control room work was detailed. This context was compared to and analyzed using reviewed literature regarding future technologies under Industry 4.0 along with my own speculations on future possibilities. The analyses consists of my reflections on what problems that existed, what could be improved and what worked well in the control rooms. Furthermore, my analyses included the positive and negative effects that the implementation of Industry 4.0 technologies could have on the control room work. The analyses were utilized as the basis for creating a vision of how control rooms can develop under Industry 4.0, and the changes that are desirable.

    The resulting vision compiled from my analyses consists of two scenarios; a dystopian and a utopian scenario. Each scenario depicts exaggerated depictions of the potential results of implementing Industry 4.0. The dystopian scenario depicts the few operators not made obsolete by an autonomous production and how they’ve been affected. They are constantly tracked and have their health monitored during their work, their equipment isn’t designed with the user in mind and the job no longer feels like qualified work. As a contrast, the utopian operators instead utilize the increased capabilities for communication and data gathering from systems and machines to work with tests, development work and optimization. Furthermore, instead of constant monitoring, tracking sensors are instead used to notify emergency personnel if the operator hurts themselves while out working. With these scenarios I also included recommendations for how the utopian vision can be achieved and the dystopian one avoided. These recommendations include involving operators in development of work tasks and instructions to promote employee involvement and control. Furthermore, their involvement allows for the better utilization of their knowledge and experiences, while also potentially helping with making the control room work better adapted to the operators’ needs. According to the results of this project, this will help improve and support efforts to create more attractive workplaces and promote qualifications development. By following the recommendations made, it is my hope that Swedish metallurgic industries like SSAB can better strive for an implementation of Industry 4.0 that is beneficial for both employer and employees.

  • Söderberg, Elin
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Förbättrad arbetsmiljö genom digital dokumentation: Ett projekt om hur ett digitaliserat dokumentationsverktyg kan öka arbetskvalitén för städare2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Support from colleagues and managers are two important factors to a good work environment. Another important support is documentation. Finding answers and information that is documented in cases of uncertainty can lead to reduced concern and a sense of security. Documentation can be carried out in different ways depending on the need and prerequisites. During this project the need of documentation at a cleaning unit have been investigated and analyzed. This report is the result of a master thesis project that took place during spring of 2019 at the Master of Science program in Industrial Design Engineering at Luleå University of Technology.

    The municipal cleaning unit carries out cleaning and floor cleaning in most premises where municipal activities are conducted in the municipality of Piteå. The cleaning unit currently has 85 permanent and 8 temporary cleaners in the organization who perform cleaning in four different geographical areas in the municipality. To get the required working hours several of the cleaners are schedule in more than one workplace. At the moment it is the cleaners task to assemble schedules when different types of cleaning are to be performed on their workplace. The documentation usually takes place in paper form and the design of the schedule varies from appearance to content between workplaces. Since these schedules are in paper form it is also difficult for workplaces to take inspiration from each other regarding the content and structure of the schedule. The fact that the variation on these schedules is so great even though they contain the same type of information leads to an uncertainty among the cleaners.

    During the project, the cleaners had to answer a survey that contained a wide range of questions to get an understanding on their thoughts regarding support, motivation, workloads among others. These questions were used to map how the cleaners experienced different topics within the organization. Observations have also been made on the cleaners where they have carried out major cleaning and allergy cleaning. The cleaning unit also had workplace meetings and an education for new cleaners during the project, which made it possible to also observe these occasions. A workshop where the cleaners had to reflect and answer various discussion issues related to documentation and information was carried out at the end of the project to collect the cleaners thoughts to use for idea and concept generation.

    The project has resulted in a solution proposal for a digitized documentation tool that the cleaning unit can carry on to development work. The solution proposal moves the now closed and locked documentation in paper format to a more open and easily accessible digitized documentation tool. The tool gives the cleaners the opportunity to, among others, learn from each other independently of workplace, get a support in case of uncertainty and get a common structure and routine within the whole cleaning unit that could improve the uncertainty that currently exists regarding documentation. Implementing a documentation tool for the cleaners would contribute with structure, uniformity, improve work environment and an opportunity to maintain knowledge within the organization. The knowledge and information that now is locked to people and workplaces could be preserved and help the cleaning unit grow and maintain status and competitiveness if documented. A digitized documentation tool could be the solution to that need.

  • Stark, Tina
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Machine learning for condition monitoring in hydropower plants using a neural network2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The hydro power industry stands for new challenges due to a more fluctuating production fromwind and solar power. This requires more regulation of the production in the hydro powerstations, which increases maintenance demands. An oil leakage has not only consequencessuch as downtimes and maintenance costs, but also an environmental impact. Skellefte ̊aKraft is working towards reaching a condition based maintenance. Therefore, the purpose ofthis master thesis is to develop a model using a feedforward neural network to predict the oillevel in the control system of a Kaplan turbine and map which sensor signals that are required.The thesis will cover data from two hydro power stations, Grytfors and B ̊atfors, each ofwhich has two units, G1 and G2. Due to limitations of the database Skellefte ̊a Kraft areusing, the data has minute resolution and covers two months, December and January. Themodel is developed in MATLAB using their Deep Learning toolbox and the neural networkfeedforwardnet. Before training and testing the model, an optimization was done. Grytforshas a full range of sensor signals while B ̊atfors has half the amount and therefore, the datafor Grytfors was used in the optimization. A grid search was done to optimize the hyperpa-rameters using cross validation. To map which input parameters that are required a featureselection was done.From the result of the feature selection, power, accumulator levels 1 and 2 and pressurewere chosen as the input parameters for Grytfors. For B ̊atfors, all of the the existing sensorsignals were used instead. The model is then trained and tested for the two different powerstations. For Grytfors, the predicted oil level follows the pattern of the real oil level but thetest error is around 15-20 liter. Four different tests were done for B ̊atfors. The two firstfor unit 1, the third for unit 2 and the fourth on both units to investigate the potential of ageneral model for one power station. For B ̊atfors, the first two tests have test errors of around4-6 liters. The third and fourth tests have test errors of around 1.5 liter. In the first twotests, the December data contains a potential refill sequence and in the third test, for unit2, the data contains start and stop sequences. The results showed the importance of havingcomprehensive training data.

  • Berbäck, Emma
    Luleå University of Technology, Department of Arts, Communication and Education, Education, Language, and Teaching.
    Varför har vi läsläxa?2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Syftet med denna studie är att synliggöra vad ett urval av lärare i årskurserna 1–3 anser vara avsikten med att ge eleverna läsläxa, samt att ta reda på om dessa lärares elever är medvetna om lärarnas avsikter. Denna kunskap kan bidra till att öka medvetenheten om syftet med läsläxa både hos lärare och elever och på så sätt göra läsläxan mer meningsfull för dem.

    För att ta reda på detta intervjuades tre lärare och sex elever i årskurserna 1–3, från samma kommun. Efter att intervjuerna var genomförda framkom det att de tre lärarna har överensstämmande avsikt med att ge sina elever läsläxa samt att de intervjuade eleverna var medvetna om lärarnas avsikt med läsläxan. Resultatet av denna studie visar att såväl lärarna som eleverna anser att läsläxan finns till för att eleverna ska träna på sin läsning. I denna undersökning framkom ytterligare ett intressant resultat, nämligen att eleverna inte förstod varför de jobbar med läsförståelsefrågor i tillhörande arbetsbok. Syftet med att svara på läsförståelsefrågor i tillhörande arbetsböcker var för eleverna oklart.

    Nyckelord: läsläxa, lärare, elever

  • Boström, David
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Roterande applikation för smutsig miljö.2019Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
  • Brandemyr, Gabriella
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Powder bed additive manufacturing using waste products from LKAB's pelletization process: A pre-study2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report is the result of a bachelor thesis project executed at Luleå University of Technology(LTU). The purpose of the project was to investigate the possibility to use the metal powder wasteproducts from LKAB’s pelletizing process for additive manufacturing as this would meaneconomic benefits for the sake of LKAB as well as environmental benefits.Two different powders were used in the experiments and were referred to as crush and dust. Theexperiments were made through the selective laser melting (SLM) method with varying laserparameters to observe their effect. These included the laser power and laser speed. Scanningelectron microscope (SEM), Energy Dispersive X-Ray Spectroscopy (EDS) and opticalmicroscopy were used for the analysis of the samples.The analysis of the chemical compositions showed that the powders were inhomogeneous anddiffered from each other. The crush powder contained phosphor and carbon which was lacking inthe dust and also had higher amounts of silicon and potassium. In spite of the inhomogeneouspowder and getting some agglomerations of half-melted grains on the tracks, the tracks tended tobe mostly homogenous. It was also observed that the tracks have a higher amount of carboncompared to the powder which probably derives from the substrate plate.The adherence of the tracks was greatest at a laser power between 200-300 W and a laser scanningspeed 0.5-1.75 m/min.The metal powder waste products from LKAB’s pelletization process could likely be used inadditive manufacturing, however, more work is needed in order to ensure the obtained results andcontinue with further experiments.

  • Carlson, Hampus
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Lejon, Isak
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Blockchain business networks: Understanding the value proposal within centralized and decentralized governance structures2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Purpose increasing the understanding of what distinguish a decentralized from a centralized blockchain business network and identify its value creating mechanisms. To fulfill this research purpose, three research questions have been derived, RQ1: What distinguishes a decentralized from a centralized blockchain business network?, RQ2: How are the blockchain business network values affected by a decentralized vs centralized network model? and RQ3: Which value creating mechanisms exists within decentralized blockchain networks?

    Method – This study was conducted as an abductive explorative study with interviews of actors that works with their own blockchain or is an expert in the subject, respondents from 9 different industries were participating. In total 25 interviews were held in two phases and they were together with a workshop analyzed through a thematic analysis.

    Findings – The findings from the study resulted in a framework including four separate areas, namely, Governance models, Blockchain values, Business network values and Value creating mechanisms. There were three governance modes, Lead organization, Network administrative organization and Participant owned organization. Furthermore, this study has resulted in 12 blockchain values, 11 network values and 9 value creating mechanisms.

    Theoretical and practical implications – This study gives an answer to the question what distinguish the decentralized and centralized nature of a blockchain business network, stating that the most value critical factor is the choice of network governance model. Furthermore, additional examples of blockchain and network values have been presented and those values have been analyzed through three different governance models. Also, the 9 value creating mechanisms have been described and analyzed from a decentralized blockchain network perspective. The practical implications give managers insight of which value creating mechanisms that exists for a decentralized blockchain business network, an understanding that could help them decide on if blockchain fits their business needs or not. Lastly, by providing an overview of which the strengths and weaknesses are of different governance models for a blockchain business network, managers could better align their network governance.

    Limitations and future research – Due to the explorative nature of this study these frameworks and relationships are built from our research and will need future validation from similar study to test its applicability in a larger extent. Hence, future studies with these frameworks and matrixes as reference point would be interesting.

  • Han, Lei
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Reduction of Set-recovery of Surface densified Scots Pine by Furfuryl Alcohol2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

     For wood products such as flooring and worktop, only one surface is normally exposed in their use, and the mechanical properties like hardness and wearing resistance of that surface is then important. Since mechanical properties are strongly related to the density, surface densification, i.e. transverse compression of the wood cells beneath the surface of a piece of wood with the aim to increase the density of that region, may be a method for improving hardness and wearing resistance when low-density species are used for such products. The set-recovery, i.e. the moisture-induced swelling of the densified wood cells back to their original shape, is the main obstacle in the use of densified wood products. Although there are several methods reported in literature, such as post heat-treatment, that can almost eliminate the set-recovery, but such methods are either time consuming or difficult to implement into an industrial continuous process which may do densification competitive to techniques or materials that can achieve at least the same hardness.

        In the present study, furfuryl alcohol was used as pre-treatment to fix the set-recovery of surface-densified Scots pine sapwood. The main effect and interactive influence of four process parameter (impregnation time, press temperature, press time and compression ratio) on set-recovery and Brinell hardness after two wet-dry cycles were studied by a two-level full factorial design of experiments. The characterizing variables of the density profile after the surface densification and set-recovery test were carried out as a supplementary tool to learn the mechanism of this two-step modification process. According to the result, the surface densified wood with furfuryl alcohol pre-treatment can retain their dimension and keep hardness at a very high level after two wet-dry cycles. The set-recovery and hardens after two wet-dry cycles were about 20 % and 30 N/mm2, respectively. The Pearson correlation analysis shows that the correlation coefficients between set-recovery with impregnation time, press temperature, press temperature, compression ratio were -0.35, -0.52, -0.37, and 0.16, respectively. That means that for the specimens with furfuryl alcohol pre-treatment, the higher press temperature can reduce the set-recovery significantly. The longer press time and impregnation time can also reduce the set-recovery in some extent, but the influence was  low. As expected, the hardness improvement was retained with low set-recovery. The lowest set-recovery value was 14% with the corresponding hardness of 41 N/mm2 was achieved by specimens processed with 120 minutes of impregnation, 10% compression ratio, 210℃ pressing temperature, and 15 minutes of pressing time. With 20 minutes of impregnation time, 10% compression ratio, 210℃ pressing temperature, and 5 minutes of pressing time, the sample still owns twofold hardness after the set-recovery test.

  • Ali, Ammar A.
    et al.
    College of Engineering, University of Baghdad, Baghdad, Iraq .
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Al-Suhail, Qusay
    College of Science, University of Baghdad, Baghdad, Iraq.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Spatial total load rating curve for a large river: A Case study of the Tigris River at Baghdad2019In: International Journal of River Basin Management, ISSN 1571-5124, E-ISSN 1814-2060Article in journal (Refereed)
    Abstract [en]

    The Tigris River in Baghdad is a large sand-bed river, supply-limited because of the implementation of a water flow regulation scheme comprising a series of reservoirs and barrages.  The significant reduction in the water discharge has affected the hydraulic performance of the river and turned it into an under-fit river of complicated morphology where many islands and bank deposits have been showed up across an 18km reach in addition to the essential sinuosity. Measuring sediment load at individual cross-sections in the river gives misleading estimates and the corresponding sediment rating curve has a locally limited using. A spatially sediment rating by investigating sediment loads over the complicated reach is required to overcome the local limitations. Sediment transport rates have been investigated at 16 cross-sections along the study reach by collecting suspended load, bed load and bed material samples. Velocity profiles were measured at the sampling stations using an Acoustic Doppler Current Profiler (ADCP). The measurement results indicated that the suspended load is the dominant mode of transport (93.5%). However, bedloads were considered in determining the total loads. A spatial total load rating curve in the form of a power function was established and examined against the sediment measurements. Twenty-two previously published total load formulae where applied at the same sections and of these the Colby1964 formula gave the closest fit to the measured loads. Based on the results from this study a recommended procedure is established for using a spatial total load rating curve to estimate sediment transport rates for similar morphologically complicated rivers. Average annual transport rates during the period 2009-13 was estimated at 3.21 million tons.

  • Eriksson, Per-Erik
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Larsson, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Industrilized and sustainable construction.
    Szentes, Henrik
    Lund University.
    Reactive Problem Solving and Proactive Development in Infrastructure Projects2019In: Current Trends in Civil & Structural Engineering, ISSN 2643-6876, Vol. 3, no 2Article in journal (Refereed)
  • Naji, Laith A.
    et al.
    Department of Environmental Engineering, College of Engineering, University of Baghdad, Iraq.
    Jassam, Salim H.
    Department of Building and Construction Technology Engineering, Technical College Baghdad, Middle Technical University.
    Yaseen, Mohammed J.
    Department of Environmental Engineering, Mustansiriayah University, Baghdad, Iraq.
    Faisal, Ayad A. H.
    Department of Environmental Engineering, College of Engineering, University of Baghdad, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Modification of Langmuir model for simulating initial pH and temperature effects on sorption process2019In: Separation science and technology (Print), ISSN 0149-6395, E-ISSN 1520-5754, Separation Science and Technology, ISSN 0149-6395Article in journal (Refereed)
    Abstract [en]

    The present study modifies the sorption isothermfor simulating the influences of initial pH and temperature variations on thecadmium sorption from contaminated water using waste foundry sand based on Langmuir,Freundlich and Temkin models. Results proved that the Langmuir expression is ableto adopt these effects by relating sorption capacity and affinity constantswith pH and temperature of aqueous solution through exponential relationships (determinationcoefficient = 0.9375). The present model is assumed that the sorption process occursthrough acidic functional groups and this is consistent with FTIR outputs. Interactionof cadmium/WFS is found to be exothermic by thermodynamic analysis.

  • Kleyko, Denis
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Rahimi, Abbas
    ETH Zurich, Zurich, Switzerland.
    Gayler, Ross W.
    Melbourne, Australia.
    Osipov, Evgeny
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Autoscaling Bloom filter: Controlling trade-off between true and false positives2019In: Neural computing & applications (Print), ISSN 0941-0643, E-ISSN 1433-3058Article in journal (Refereed)
    Abstract [en]

    A Bloom filter is a special case of an artificial neural network with two layers. Traditionally, it is seen as a simple data structure supporting membership queries on a set. The standard Bloom filter does not support the delete operation, and therefore, many applications use a counting Bloom filter to enable deletion. This paper proposes a generalization of the counting Bloom filter approach, called “autoscaling Bloom filters”, which allows adjustment of its capacity with probabilistic bounds on false positives and true positives. Thus, by relaxing the requirement on perfect true positive rate, the proposed autoscaling Bloom filter addresses the major difficulty of Bloom filters with respect to their scalability. In essence, the autoscaling Bloom filter is a binarized counting Bloom filter with an adjustable binarization threshold. We present the mathematical analysis of its performance and provide a procedure for minimizing its false positive rate.

  • Granlund, Cajsa
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Prick, Lisa
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    A study of viral marketing on Youtube: Evidence: Nike Dream Crazy and Nike Dream Crazier2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim with this study was to answer the question “What components in Nike’s viral ads on Youtube trigger emotions?”. The data was collected through a qualitative and descriptive research approach and the method was a combination of a poetic film analysis and Ducoffe’s Model of Advertising Value. The model includes three components that were to be analyzed: informativeness, entertainment and irritation. The video ads were analyzed together with the comments posted. The comments were seen as electronic word of mouth and they were analyzed in order to understand if the viewer felt positive or negative emotions towards the ads. The findings showed that Ducoffe’s Model of Advertising Value was applicable on social media networks such as Youtube. Informativeness and entertainment were the most important components triggering emotions. Since marketing events nowadays are digitalized, it is important to adapt previous models and research to new platforms.

  • Adelbrun, Alina
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Vad innebär lagreformen för organdonation?: En studie av de rättsliga följderna av den statliga utredningen2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I samband med den statliga donationsutredningen förväntades en lagreform som skulle öka donationsfrekvensen. En sådan reform uteblev dock och det finns anledning att ifrågasätta varför det blev på det sättet. Arbetets syfte har varit att ta reda på orsaken till den uteblivna lagreformen i donationsfrågor efter donationsutredningens slut, samt att uppmärksamma de ändringar som trots allt har införlivats. För att kunna besvara frågeställningarna har den rättsdogmatiska metoden använts, med rättskälleläran som grund, för att fastställa gällande rätt före och efter den statliga utredningen om organdonationer. Utredningen visar att efter att utredningsbetänkandet och de dithörande remissvaren hade analyserats kunde det konstateras att lagförslagen inte kunde införas på grund av oförenlighet med grundlagen. Vissa av donationsutredningens förslag har dock ändå införlivats och beslut om en ny förordning gällande donationsregistret har fattats.

  • Isaksson, Ingeborg
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Waara, Johanna
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Hur påverkar fysisk aktivitet mentalt välmående hos universitetsstudenter?: En kvantitativ studie2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study aims to examine the mental well-being and physical activity among university students. And to examine whether it is possible to determine whether there is a significant correlation between these.The sample of the research consists of 55 volunteering students (n=37 female and n=18 male) who study at a state university in Sweden. A quantitative method in the form of a questionnaire has been used in this study in order to gather data regarding mental health and physical activity. the questionnaire contained 14 questions with different types of questions such as self-scaling and open questions. The result indicated that most of the participants of this study is quite active and is generally quite healthy-minded. The programme SPSS was used for the statistical analysis of the data collected for the present research. According to the findings of the statistical analysis is that there is a weak positive correlation between the variable’s mental health and physical activity. 

  • Lindvall, Emelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Täta hus: en litterturstudie om lufttäthet samt en tolkning av samband mellan lufttäthet och brandtryck2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    During the 60’s and 70’s the population grew steadily in Sweden. Due to industrialization many people made the decision to move from the countryside to the city. This led to a housing shortage and the so called million program was adopted by the Swedish governmentone million dwellings had to be built within a short amount of time. 

    The building process had to be effective, leading to the introduction of prefabricated building components. The dwellings were heated using oil since it was economically favorable at that time. When the oil crisis unfolded in 1973, energy rationing actions were introduced, and the buildings had to be additionally insulated.

    The million program dwellings are today in need of extensive renovations since the buildings are damaged by damp. There have been considerable changes in the building regulations as well, mainly regarding energy, insulation and airtightness.

    The building regulations says that a building construction should have as fair airtightness as possible to prevent damage by damp and moisture, as well as to minimize the use of energy and the climatic influence. Fair airtightness is a good thing, but with airtightness being too good there might arise problems when evacuating due to fire, especially if the door opens inward. An airtight construction may cause higher fire pressures which in turn act as an additional opening force needing to be transcended when evacuating.

    To analyze the correlation between airtightness and fire pressure a parameter analysis has been conducted using the simulation program FDS. Simulations do validate previously conducted fire experiments where difficulties to transcend an inwards opening door emerged. For the parameter analysis the airtightness has been changed, from 0,73 to 0,30 l/sm2. The ventilation figuration has been varied between open and closed.

    The result demonstrated the fire pressure rising when the airtightness improved. The maximum pressure of 6 100 Pa occurred with a combination of airtightness 0,30 l/sm2and closed ventilation. The lowest fire pressure of 700 Pa occurred when the airtightness was set to 0,73 l/sm2and the ventilation was open.

    Maximum door opening forces are according to the Swedish building regulations, Boverkets byggregler,25 N and 150 N, depending on whether the door is constructed to be opened by a person with disabilities or not. Door used for evacuation should be opened outwards, but an inward opening door may be used in dwellings, hotels and smaller workplaces. The rule of thumb says that an operating opening force of 150 N can transcend a back pressure of 150 Pa. 

    To be able to transcend a door effected by fire pressure between 700 Pa and 6 100 Pa, whilst using the regulated opening forces, evacuation must be carried out within seconds. People being asleep, intoxicated or experiencing difficulties moving due to old age or disability, risk being affected by fire pressure in the sense of a delayed evacuation resulting in higher fire pressures, thus implying greater openings forces.

  • Mattsson, Johanna
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Odlingslandskapet: Miljöersättningar och det rättsliga skyddet för biologisk mångfald2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the thesis is to investigate the protection of biodiversity at the global level, within the EU and in Swedish law. Furthermore, the presentation aims to shed light on the biological diversity of the cultivated landscape, the threats to it and the effectiveness of environmental payments as a means of controlling the loss of biodiversity. In order to answer the purpose, a traditional legal analysis has been used, which has been supplemented by a legaleconomic analysis to determine whether environmental payments can be considered an effective policy instrument. The threats to biodiversity in the cultivation landscape consist partly of intensified agriculture, which deprives the species of their habitats by changing the use of the land and partly of the fact that agriculture is abandoned. In order to reverse the trend of reduced biodiversity, the variation needs to increase where agriculture is intensive, and in areas where agriculture is closed down, measures that contribute to the continuation of agriculture are necessary. Environmental compensation is an economic policy instrument used to reduce the loss of biodiversity in the agricultural landscape. The results of the study indicates that economic compensation indeed is an important instrument to preserve diversity in the cultivation landscape, but that it should be designed in a more efficient way, for example by being based on value and result rather than cost and action as is the case today.

  • Nyberg, Ulrika
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Knutsson, Sara
    Luleå University of Technology, Department of Health Sciences.
    Patienters upplevelse av bemötande från distriktssköterskan inom palliativ hemsjukvård2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Most of the patients with a palliative diagnose want to be taken care of in their own homes. This is possible with help from a team consisting of among others; district nurses, assistant nurses and significant others. Patients living at home often experience better quality of life, compared to them taken care of at the hospital. The district nurse is responsible that the care is well functioning and is the best care for the patient. How the patient experience the treatment from the district nurse is very interesting. What the patient value in the treatment to make it feel genuine and credible. The encounter in the care relationship is important for the patient to feel seen and be involved in their own care. Aim: The aim of the study was to describe patients with a palliative diagnosis how they experienced the encounter from the district nurse in home care. Method: A qualitative approach has been used and eight patients has been interviewed. Results: The results became three categories: To have time, be seen and have respect. To feel safe and continuity, and to be takenseriously and involved in their own care. Conclusion: For the patients to experience a good encounter it takes continuity, correct information and a possibility to take part in their own care. To have time with the district nurse and to feel seen by the district nurse is important.

  • Sjöholm, Jennie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Norrbotten's Technological Megasystem2019In: TICCIH Bulletin, ISSN 1605-6647, Vol. 85, p. 3-6Article in journal (Other (popular science, discussion, etc.))
  • Vidal, Brenda
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Barraud, Sylvie
    Department of Civil Engineering and Urban Planning, National Institute of Applied Sciences of Lyon.
    Kärrman, Erik
    Division of the Built Environment, Research Institutes of Sweden.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Assessing the sustainability of on-site sanitation systems using multi-criteria analysis2019In: Environmental Science: Water Research & Technology, ISSN 2053-1400Article in journal (Refereed)
    Abstract [en]

    Small on-site sanitation systems are widely present in suburban and rural areas in many countries. As these systems often underperform and have an impact on receiving waters, understanding their overall sustainability is of interest for policy and decision-makers. However, the definition and estimation of indicators defining sustainability are challenging, as it is finding the methodological approach to combine qualitative and quantitative indicators into one comprehensive assessment. In this study, twelve indicators defined by environmental, economic, social, technical and health-related criteria were used to compare nine alternatives of on-site sanitation for single households. A non-compensatory method for multi-criteria decision analysis, ELECTRE III, was used for the assessment together with weights assigned to each indicator by a reference group. Several scenarios were developed to reflect different goals and a sensitivity analysis was conducted. Overall, the graywater–blackwater separation system resulted as the most sustainable option and, in terms of polishing steps for phosphorus removal, chemical treatment was preferred over the phosphorus filter, both options being implemented together with sand filters. Assessing the robustness of the systems was a crucial step in the analysis given the high importance assigned to the aforementioned indicator by the stakeholders, thus the assessment method must be justified. The proposed multi-criteria approach contributes to aid the assessment of complex information needed in the selection of sustainable sanitation systems and in the provision of informed preferences.

  • Salih, Sinan Q.
    et al.
    Institute of Research and Development, Duy Tan University, Da Nang, Vietnam.
    Allawi, Mohammed Falah
    Department of Civil Engineering, Al-Esraa University College, Baghdad, Iraq.
    Yousif, Ali A.
    Water Resources Engineering Department, College of Engineering, University of Duhok, Duhok, Iraq.
    Armanuos, Asaad M.
    Irrigation and Hydraulics Engineering Department, Civil Engineering Department, Faculty of Engineering, Tanta University, Tanta, Egypt.
    Saggi, Mandeep Kaur
    Department of Computer Science, Thapar Institute of Engineering and Technology, Patalia, India.
    Ali, Mumtaz
    Deakin-SWU Joit Research Centre on Big Data, School of Information Techonology, Deakin University, Victoria, Australia.
    Shahid, Shamsuddin
    School of Civil Engineering, Faculty of Engineering, Faculty of Civil Engineering, Universiti Teknologi Malaysia (UTM).
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Yaseen, Zaher Mundher
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Chau, Kwok-Wing
    Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
    Viability of the advanced adaptive neuro-fuzzy inference system model on reservoir evaporation process simulation: case study of Nasser Lake in Egypt2019In: Engineering Applications of Computational Fluid Mechanics, ISSN 1994-2060, E-ISSN 1997-003X, Vol. 13, no 1, p. 878-891Article in journal (Refereed)
    Abstract [en]

    Reliable prediction of evaporative losses from reservoirs is an essential component of reservoir management and operation. Conventional models generally used for evaporation prediction have a number of drawbacks as they are based on several assumptions. A novel approach called the co-active neuro-fuzzy inference system (CANFIS) is proposed in this study for the modeling of evaporation from meteorological variables. CANFIS provides a center-weighted set rather than global weight sets for predictor–predictand relationship mapping and thus it can provide a higher prediction accuracy. In the present study, adjustments are made in the back-propagation algorithm of CANFIS for automatic updating of membership rules and further enhancement of its prediction accuracy. The predictive ability of the CANFIS model is validated with three well-established artificial intelligence (AI) models. Different statistical metrics are computed to investigate the prediction efficacy. The results reveal higher accuracy of the CANFIS model in predicting evaporation compared to the other AI models. CANFIS is found to be capable of modeling evaporation from mean temperature and relative humidity only, with a Nash–Sutcliffe efficiency of 0.93, which is much higher than that of the other models. Furthermore, CANFIS improves the prediction accuracy by 9.2–55.4% compared to the other AI models.

  • Lööw, Joel
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human and technology.
    Abrahamsson, Lena
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human and technology.
    Johansson, Jan
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human and technology.
    Mining 4.0—the Impact of New Technology from a Work Place Perspective2019In: Mining, Metallurgy & Exploration, ISSN 2524-3462, Vol. 36, no 4, p. 701-707Article in journal (Refereed)
    Abstract [en]

    Industry 4.0 offers new possibilities to combine increased productivity with stimulating workplaces in a good work environment. Used correctly, digitalization can create attractive jobs in safe control room environments, which provide space for the employee’s full expertise and creativity. This is true also for the mining industry. But, to succeed, it is important to analyze the development from a worker’s perspective. What will happen to their work? What skills will be needed in the mine of tomorrow? We must also consider the risks, such as privacy issues, increased stress, and work-life boundaries. These questions must be understood if we are to create workplaces that can attract a young and diverse workforce to tomorrow’s mining industry. In this article, we try to illustrate what the new technology can mean for the individual miners. We formulate the notion of Mining 4.0 (Industry 4.0 in the mining industry), where we try to create an image of how the future might look from a miner’s perspective and how mining companies may navigate their way to a future that works for all miners. To illustrate the range of possible outcomes, we formulate two scenarios: one utopian and one dystopic. At the end of our article, we bring forward six recommendations that can be considered a beginning of a road map for the human side of Mining 4.0.

  • Jing, Wang
    et al.
    Department of Computer Science, Baoji University of Arts and Sciences, Shaanxi, People’s Republic of China. Faculty of Computer Systems & Software Engineering, University Malaysia Pahang, Pahang, Malaysia.
    Yaseen, Zaher Mundher
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Shahid, Shamsuddin
    School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia.
    Saggi, Mandeep Kaur
    Department of Computer Science, Thapar Institute of Engineering and Technology, Patiala, India.
    Tao, Hai
    Department of Computer Science, Baoji University of Arts and Sciences, Shaanxi, People’s Republic of China.
    Kisi, Ozgur
    Faculty of Natural Sciences and Engineering, Ilia State University, Tbilisi, Georgia.
    Salih, Sinan Q.
    Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Chau, Kwok-Wing
    Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, People’s Republic of China.
    Implementation of evolutionary computing models for reference evapotranspiration modeling: short review, assessment and possible future research directions2019In: Engineering Applications of Computational Fluid Mechanics, ISSN 1994-2060, E-ISSN 1997-003X, Vol. 13, no 1, p. 811-823Article in journal (Refereed)
    Abstract [en]

    Evapotranspiration is one of the most important components of the hydrological cycle as it accounts for more than two-thirds of the global precipitation losses. Indeed, the accurate prediction of reference evapotranspiration (ETo) is highly significant for many watershed activities, including agriculture, water management, crop production and several other applications. Therefore, reliable estimation of ETo is a major concern in hydrology. ETo can be estimated using different approaches, including field measurement, empirical formulation and mathematical equations. Most recently, advanced machine learning models have been developed for the estimation of ETo. Among several machine learning models, evolutionary computing (EC) has demonstrated a remarkable progression in the modeling of ETo. The current research is devoted to providing a new milestone in the implementation of the EC algorithm for the modeling of ETo. A comprehensive review is conducted to recognize the feasibility of EC models and their potential in simulating ETo in a wide range of environments. Evaluation and assessment of the models are also presented based on the review. Finally, several possible future research directions are proposed for the investigations of ETo using EC.

  • Salih, Sinan Q.
    et al.
    Institute of Research and Development, Duy Tan University, Da Nang, Vietnam.
    Aldlemy, Mohammed Suleman
    Department of Mechanical Engineering, Collage of Mechanical Engineering Technology, Benghazi, Libya.
    Rasani, Mohammad Rasidi
    Centre for Integrated Design for Advanced Mechanical Systems, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, Bangi, Malaysia.
    Ariffin, A.K.
    Centre for Integrated Design for Advanced Mechanical Systems, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, Bangi, Malaysia.
    Ya, Tuan Mohammad Yusoff Shah Tuan
    Department of Mechanical Engineering, Faculty of Engineering, Universiti Teknologi Petronas, Tronoh, Malaysia.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Yaseen, Zaher
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Chau, Kwok-Wing
    Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, People’s Republic of China.
    Thin and sharp edges bodies-fluid interaction simulation using cut-cell immersed boundary method2019In: Engineering Applications of Computational Fluid Mechanics, ISSN 1994-2060, E-ISSN 1997-003X, Vol. 13, no 1, p. 860-877Article in journal (Refereed)
    Abstract [en]

    This study aims to develop an adaptive mesh refinement (AMR) algorithm combined with Cut-Cell IBM using two-stage pressure–velocity corrections for thin-object FSI problems. To achieve the objective of this study, the AMR-immersed boundary method (AMR-IBM) algorithm discretizes and solves the equations of motion for the flow that involves rigid thin structures boundary layer at the interface between the structure and the fluid. The body forces are computed in proportion to the fraction of the solid volume in the IBM fluid cells to incorporate fluid and solid motions into the boundary. The corrections of the velocity and pressure is determined by using a novel simplified marker and cell scheme. The new developed AMR-IBM algorithm is validated using a benchmark data of fluid past a cylinder and the results show that there is good agreement under laminar flow. Simulations are conducted for three test cases with the purpose of demonstration the accuracy of the AMR-IBM algorithm. The validation confirms the robustness of the new algorithms in simulating flow characteristics in the boundary layers of thin structures. The algorithm is performed on a staggered grid to simulate the fluid flow around thin object and determine the computational cost.

  • Nieto-Peroy, Cristóbal
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Emami, Reza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Aerospace Mechatronics Group, University of Toronto Institute for Aerospace Studies, Toronto, ON, Canada.
    CubeSat Mission: From Design to Operation2019In: Applied Sciences, E-ISSN 2076-3417, Vol. 9, no 15, article id 3110Article in journal (Refereed)
    Abstract [en]

    The current success rate of CubeSat missions, particularly for first-time developers, may discourage non-profit organizations to start new projects. CubeSat development teams may not be able to dedicate the resources that are necessary to maintain Quality Assurance as it is performed for the reliable conventional satellite projects. This paper discusses the structured life-cycle of a CubeSat project, using as a reference the authors’ recent experience of developing and operating a 2U CubeSat, called qbee50-LTU-OC, as part of the QB50 mission. This paper also provides a critique of some of the current poor practices and methodologies while carrying out CubeSat projects.

  • Schmidt, Johannes
    et al.
    Institute for Sustainable Economic Development, University of Natural Resources and Life Sciences, Vienna, Austria.
    Gruber, Katharina
    Institute for Sustainable Economic Development, University of Natural Resources and Life Sciences, Vienna, Austria.
    Klingler, Michael
    Institute for Sustainable Economic Development, University of Natural Resources and Life Sciences, Vienna, Austria.Department of Geography, University of Innsbruck, Austria.
    Klöckl, Claude
    Institute for Sustainable Economic Development, University of Natural Resources and Life Sciences, Vienna, Austria.
    Camargo, Luis Ramirez
    Institute for Sustainable Economic Development, University of Natural Resources and Life Sciences, Vienna, Austria.International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria.
    Regner, Peter
    Institute for Sustainable Economic Development, University of Natural Resources and Life Sciences, Vienna, Austria.
    Turkovska, Olga
    Institute for Sustainable Economic Development, University of Natural Resources and Life Sciences, Vienna, Austria.
    Wehrle, Sebastian
    Institute for Sustainable Economic Development, University of Natural Resources and Life Sciences, Vienna, Austria.
    Wetterlund, Elisabeth
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria.
    A new perspective on global renewable energy systems: why trade in energy carriers matters2019In: Energy & Environmental Science, ISSN 1754-5692, E-ISSN 1754-5706, Vol. 12, no 7, p. 2022-2029Article in journal (Refereed)
    Abstract [en]

    Recent global modelling studies suggest a decline of long-distance trade in energy carriers in future global renewable energy systems, compared to today's fossil fuel based system. In contrast, we identify four drivers that facilitate trade of renewable energy carriers. These drivers may lead to trade volumes remaining at current levels or even to an increase during the transition to an energy system with very high shares of renewables. First, new land-efficient technologies for renewable fuel production become increasingly available and technically allow for long-distance trade in renewables. Second, regional differences in social acceptance and land availability for energy infrastructure support the development of renewable fuel import and export streams. Third, the economics of renewable energy systems, i.e. the different production conditions globally and the high costs of fully renewable regional electricity systems, will create opportunities for spatial arbitrage. Fourth, a reduction of stranded investments in the fossil fuel sector is possible by switching from fossil fuels to renewable fuel trade. The impact of these drivers on trade in renewable energy carriers is currently under-investigated by the global energy systems research community. The importance of the topic, in particular as trade can redistribute profits and losses of decarbonization and may hence support finding new partners in climate change mitigation negotiations, warrants further research efforts in this area therefore.

  • Shepherd, Dean A.
    et al.
    University of Notre Dame.
    Parida, Vinit
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Wincent, Joakim
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    The Surprising Duality of Jugaad: Low Firm Growth and High Inclusive Growth2019In: Journal of Management Studies, ISSN 0022-2380, E-ISSN 1467-6486Article in journal (Refereed)
    Abstract [en]

    Western theories on creativity emphasize the importance of access to resources and the generation of innovations as a source of sustainable competitive advantage for firms. However, perhaps the emphasis on slack resources and the firm as the level of analysis may be less appropriate for understanding the benefits of individual creative problem solving in resource‐poor environments of the east; focusing solely on the firm is not sufficiently inclusive and may underestimate the benefits of creative problem solving under resource scarcity. Through an inductive interpretive case study of 12 problem solvers in the highly resource‐poor environment of rural India, we identified the antecedents, dimensions and duality of outcomes for an Indian cultural source of creative problem solving called jugaad. Jugaad relies on assertive defiance, trial‐and‐error experiential learning and the recombination of available resources to improvise a frugal quick‐fix solution. Our inductive framework provides new insights into the dual outcomes of creative problem solving from an eastern perspective; jugaad is unlikely to be a source of competitive advantage for firm growth but represents a source of enhanced wellbeing for inclusive growth.

  • Robertson, Stephanie
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Product and Production Development.
    Microstructural Effects of Controlled Dilution of High Strength Steel Wire [SR1] into S960QL2019In: Physics Procedia, ISSN 1875-3892, E-ISSN 1875-3892Article in journal (Refereed)
    Abstract [en]

    Controlled dilution experiments were conducted in a novel manner that allowed for precise dilution of base material into the wire consumables, enabling for a prompt analysis of microstructural trends as dilution is altered. Different heat cycles and cooling rates of the wire material, without base metal additions, were shown to cause different microstructures, varying from parallel plates to random or interlocking[SR1]  orientation, with varying size of packets. The proposed method enables more controlled conditions with a known dilution value from mass percentages. Chopped filler wire is weighed and added to the base metal crucible, base metal chips are also weighed and added to the filler wire in specific mass percentages. A pulsed laser irradiates the metal, melting the mixture into a sample nugget. Lack of fusion is a benefit in this method as contamination from the base plate is negligible. The cooling rate is influenced by the pulse shape, and can be used to reheat the nugget, demonstrating the microstructural evolution in a complex thermal cycle. This method is demonstrated for S960QL steel with under-matched wire consumable, generally used for laser-arc hybrid processes to obtain high toughness, where a representative thermal cycle is needed. The thermal cycle is measured via a remote process, Dualscope, to evaluate the spacial temperature of the surface. The microstructures found using the snapshot method are similar to those found in the narrow gap multi-layer weld, different only in the size of the grains and packets.

  • Robertson, Stephanie
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Product and Production Development.
    Frostevarg, Jan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Product and Production Development.
    Kaplan, Alexander
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Product and Production Development.
    Hong, Seong Min
    Department of Welding and Joining Science Engineering, Chosun University, Gwangju, Republic of Korea.
    Kim, Jong-Hee
    Department of Welding and Joining Science Engineering, Chosun University, Gwangju, Republic of Korea.
    Bang, Hee-Song
    Department of Welding and Joining Science Engineering, Chosun University, Gwangju, Republic of Korea.
    Tailored laser pulse method to manipulate filler wire melt metallurgy from thermal cycles2019In: Journal of laser applications, ISSN 1042-346X, E-ISSN 1938-1387, Vol. 31, no 2, article id 022605Article in journal (Refereed)
    Abstract [en]

    A robust method is introduced to simulate and study the filler wire metallurgy for controlled cooling conditions after melting, enabling efficient mapping with prompt analysis of trends. Proposed is a reduced, though representative, process with more controllable conditions. Short lengths of filler wires are preplaced in a cavity, drilled into a base metal sheet. Irradiation by a pulsed laser beam melts the wire to generate a sample nugget. Pulse shaping influences the cooling rate, granting the ability to tailor weldament microstructures. The method is demonstrated for S1100QL steel and undermatched filler wire, to obtain high toughness for processes like laser-arc hybrid welding, where a representative thermal cycle is needed. For high toughness, a controlled amount of acicular ferrite and, in turn, nonmetallic inclusions is desirable. This “snapshot” method has revealed a characteristic histogram of inclusion sizes, for different pulse shapes. Additional information on the thermal cycle can be acquired by employing thermocouples, a pyrometer, or advanced methods like high speed imaging or modeling. The method offers a wide spectrum of variants and applications.

  • Khajehei, Hamid
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Ahmadi, Alireza
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Soleimanmeigouni, Iman
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Nissen, Arne
    Trafikverket, Luleå, Sweden.
    Allocation of effective maintenance limit for railway track geometry2019In: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980Article in journal (Refereed)
    Abstract [en]

    The objective of this study has been to develop an approach to the allocation of an effective maintenancelimit for track geometry maintenance that leads to a minimisation of the total annual maintenancecost. A cost model was developed by considering the cost associated with inspection, preventivemaintenance, normal corrective maintenance and emergency corrective maintenance. The standarddeviation and extreme values of isolated defects of the longitudinal level were used as quality indicatorsfor preventive and corrective maintenance activities. The Monte Carlo technique was used tosimulate the track geometry behaviour under different maintenance limit scenarios and the effectivelimit was determined which minimises the total maintenance cost. The applicability of the model wastested in a case study on the Main Western Line in Sweden. Finally, a sensitivity analysis was carriedout on the inspection intervals, the emergency corrective maintenance cost and the maintenanceresponse time. The results show that there is an optimal region for selecting an effective limit.However, by considering the safety aspects in track geometry maintenance planning, it is suggestedthat the lower bound of the optimal region should be selected.

  • Nissilä, Tuukka
    et al.
    Fibre and Particle Engineering Research Unit, Faculty of Technology, University of Oulu, Oulu, Finland.
    Oksman, Kristiina
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Fibre and Particle Engineering Research Unit, Faculty of Technology, University of Oulu, Oulu, Finland.Mechanical & Industrial Engineering (MIE), University of Toronto, 5 King’s College Road, Toronto, ON, Canada.
    Hietala, Maiju
    Fibre and Particle Engineering Research Unit, Faculty of Technology, University of Oulu, Oulu, Finland.
    A method for preparing epoxy-cellulose nanofiber composites with an oriented structure2019In: Composites. Part A, Applied science and manufacturing, ISSN 1359-835X, E-ISSN 1878-5840, Vol. 125, article id 105515Article in journal (Refereed)
    Abstract [en]

    A method was developed for processing cellulose nanocomposites using conventional vacuum infusion. Porouscellulose nanofiber networks were prepared via ice-templating and used as preforms for impregnation with a bioepoxyresin. Microscopy studies showed a unidirectionally oriented micrometer-scale pore structure that facilitatedthe infusion process by providing flow channels for the resin. The permeability of the preforms wascomparable to that of natural fiber mats, and the infusion time significantly decreased after optimizing theprocessing temperature. The flexural modulus of the bio-epoxy increased from 2.5 to 4.4 GPa, the strengthincreased from 89 to 107 MPa, and the storage modulus increased from 2.8 to 4.2 GPa with 13 vol% cellulosenanofibers. The mechanical properties also showed anisotropy, as the flexural and storage moduli were approximately25% higher in the longitudinal direction, indicating that the nanofiber network inside the epoxymatrix had an oriented nature.

  • Lindberg, Malin
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human and technology.
    Gross, Svetlana
    Stockholm School of Economics. Humsamverkan.
    Rönn, Milda
    Humsamverkan.
    Nordin, Lissa
    Swedish Research Council for Sustainable Developmen.
    Sandred, Jan
    VINNOVA.
    Wärngård, Lars
    Swedish Research Council for Health, Working life and Welfare.
    Norberg, Catharina
    The Swedish Energy Agency.
    Inclusive funding for enhanced impact of social sciences and humanities2019In: fteval Journal for Research and Technology Policy Evaluation, ISSN 1726-6629, no 48, p. 82-87Article in journal (Refereed)
    Abstract [en]

    In order to expand the knowledge on how societal impact of social sciences and humanities (SSH) can be enhanced through public funding of research and innovation, a process of designing digitalised tools for inclusive funding is scrutinised, involving four Swedish funding agencies and an Non-Governmental Organisation (NGO) of SSH researchers. The agencies shared the challenge to attract a broader range of SSH researchers to apply for their funding. Excluding and including mechanisms were identified in the interactions, texts and images of the formulation, communication and processing of calls for funding. The developed tools digitally guide the user through queries regarding the present and potential diversity of SSH representation among applicants, reviewers, agencystaff, etc. and regarding the formulation and communication of call texts, assessmentcriteria and reviewer instructions. The tools thus enhance SSH impact by making funding more available, but fail to demonstrate how concrete interaction with societal actors may enhance this.

  • Pesämaa, Susanne Björkskog
    et al.
    Luleå University of Technology, Department of Arts, Communication and Education.
    Vennberg, Maud
    Luleå University of Technology, Department of Arts, Communication and Education.
    Specialpedagogiska rollen och dess effekter på elev- och pedagogisk prestation: En enkätstudie med självskattningar från 132 pedagoger i en medelstor kommun2019Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Special educators needs coordinator enter a professional role in Swedish schools, which is theoretically conditioned by other colleagues and which is determined by educational activities such as teaching, supervision, documentation, school development and health promoting activities. Role theory and empirical research show that roles affect performance in various ways. At school, student performance and pedagogical performance are key performance measures to understand the environment in which special educators operate. Based on previous studies, this thesis proposes a unique conceptualization with multivariate measures that target roles defined by pedagogical activities and multivariate measures of performance. To follow up the conceptualization, a pilot study was conducted, and the questionnaire was revised. The applicability of the questionnaire was finally tested on 132 educators in a medium-sized municipality where all occupational groups surrounding a special educator were included. The results show that the role of the special educator is unique and fulfills different purposes depending on what performance the role is directed at. For example, we see that special educational roles such as teaching, supervision and school development are important for the student's performance. Furthermore, we see that documentation, school development and student health promotion activities have a statistically significant impact on the pedagogical performance. Since this is a first attempt to uniquely conceptualize how concrete practical pedagogical professional activities affect performance, we believe that the study can not only inspire continued research in the field, but also supports job descriptions and organization of the pedagogical work pursued by leaders of a school.

     

  • Bergman, Susanne
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Nilsson, Anna
    Luleå University of Technology, Department of Health Sciences.
    Ambulanspersonals upplevelser av samverkan vid prehospital händelse på landsbygd2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: De senaste årtiondena har det skett en centralisering av sjukvården vilket i kombination med begränsade resurser prehospitalt leder till långa avstånd innan ambulans och patient når den enhet som erbjuder den vårdnivå som krävs. På landsbygden är god samverkan med andra yrkeskategorier grundläggande för att uppnå ett optimalt omhändertagande av patienter på händelseplats. Syfte: Att studera Ambulanspersonals upplevelser av samverkan vid Prehospital händelse på landsbygd. Metod: Data insamlades genom semistrukturerade intervjuer i fokusgrupper med totalt 12 deltagare från en ambulansstation belägen på landsbygden i norra Sverige. Intervjumaterialet transkriberades och analyserades med kvalitativ innehållsanalys. Resultat: Analysprocessen resulterade i fyra kategorier: Att bristande resurser leder till utsatthet och känslan av otrygghet, Att egna initiativ är nödvändigt för att främja samverkan, Att tydlig information och god kommunikation är en förutsättning för samverkan samt Att förbättrade rutiner krävs för att utveckla samverkan. Ambulanspersonalen upplevde en utsatthet på grund av långa avstånd till både sjukhus och närmsta sjukvårdsresurs. Få medicinska resurser ställer högre krav på att samverkan med andra yrkeskategorier fungerar för ett optimalt omhändertagande av patienter i en prehospital miljö. En god samverkan grundade sig i en vilja att hjälpa till i omvårdnaden för patientens bästa. Brister i samverkan orsakades bland annat av uteblivna övningstillfällen samt utebliven återkoppling med andra resurser när samverkan skett. Slutsats: För en bra samverkan vid omhändertagande av patienter krävs god kommunikation mellan yrkeskategorier, mer gemensamma övningar samt utveckling av befintliga rutiner och riktlinjer.

  • Haglöf, Jesper
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Cooling Air Management For Hybrid Electric Vehicles Using Combined 3D Aerodynamic & Thermodynamic CFD: For External Automotive Aerodynamics2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This is a master thesis report in vehicle aerodynamics and cooling air management. The thesis is carried out at China Euro Vehicle Technology (CEVT) AB and is part of the course P7010T, Master Thesis in Space Engineering at Luleå University of Technology (LTU). The thesis has been supervised by Mattias Olander at CEVT and Gunnar Hellström at LTU and was done over 20 weeks during the spring semester of 2019. As the vehicle industry moves from mostly using combustion engines to hybrid and electric power systems the importance of decreasing cooling air drag has increased. Cooling air drag can be around 5-15% of the total drag, and a lot of research has been done over the years on how to decrease it. Cooling drag is defined as the force acting in x-direction from the cooling air flowing through the engine bay. The air is let in through the grilles to cool down the engine and escapes through different outtakes usually below the vehicle and through the wheelhouse. The air loses a lot of energy inside the engine bay as well as it changes in temperature. In this study a method has been developed to include the energy equation in the aerodynamic computational fluid dynamics (CFD) simulation. Research has also been done on which design parameters that affect the cooling air drag and how air ducts could be designed to better transport the flow to and from the radiators without loosing to much in energy. In the first part of this study a method was developed to solve the vehicle aerodynamics with energy equation included. All method development and design parameter tests weredone on the Sport Utility Vehicle (SUV) A model, which is a CEVT concept car. The model was first implemented on a simple symmetric model and then on a full model. It was tested both with a normal steady state solution and a pseudo transient solutions. The pseudo transient solution proved to solve for a faster convergence, although both methods worked well. Therefore the design parameter testing was chosen to be done with the pseudo transient solver.The design parameter testing was done in two steps, first opening and closing different outlets and then trying to implement different cooling air ducts. The first study showed that air through the wheelhouses increases the drag as well as having air entering only inthe upper grille and travelling down through floor and wheelhouse. In the second study,the area between the grilles and cooling package was sealed and inlet ducts were created to control the flow from the grilles to the cooling package. When just adding inlet ducts, the mass flow through the grilles was decreased, but the mass flow through the cooling package was increased due to less separation of the air, which lead to a drag reduction of 0.2%. Other design implementations was to reshape the wheelhouse outlets, therefore a wheelhouse outlet duct was designed. The ducts purpose was to lead the air out of the wheelhouse and behind the tire and exit the vehicle parallel to the free stream flow. The wheelhouse duct is most effective and decreases the drag force by 0.7%. An air duct was also designed to lead the flow after the cooling package fan to the outlets. The ducts purpose was to prevent the air from loosing in energy when rising to the roof of the engine bay, the duct compresses the air and leads it efficiently over the engine with a drag force decrease on 0.3%. The inlet duct, wheelhouse duct and after fan duct was all put together to a thesis design. Due to the higher mass flow through the cooling package the upper grille could be sealed by 9.9% and still allow the same mass flow through the cooling package as for the SUV A. The thesis design for improved cooling air management allowed a decrease of drag force timesarea by 0.9%. In conclusion there is much that can be done to improve the cooling air drag. It is most favorable to have a sealed volume with inlet air ducts before the cooling package, have outtakes aligned with the free stream flow, minimize cooling air to escape through the wheelhouse outlets and to minimize the height of the engine bay as much as possible.

  • Larsson, Magdalena
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Toroczkay, Sandra
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Ambulanssjuksköterskors upplevelse av kommunikation via Rakel-systemet och kommunikationskanalen för räddningstjänst, ambulans, polis och SOS2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: Att kunna kommunicera på ett säkert och enkelt sätt är en förutsättning för att kunna samverka och utföra en säker och snabb insats vid olycka. Syfte: Att beskriva ambulanssjuksköterskors upplevelse av kommunikation via Rakel-systemet och kommunikationskanalen för räddningstjänst, ambulans, polis och SOS (RAPS). Metod: Data insamlades genom semistrukturerade intervjuer med sju specialistutbildade sjuksköterskor. Intervjumaterialet transkriberades och analyserades med kvalitativ innehållsanalys. Resultat: Analysprocessen resulterade i tre kategorier; Det är frustrerande när kommunikationen inte fungerar; Systemet är en trygghet och ett hjälpmedel för ambulanssjuksköterskor; Det behövs mer utbildning och övning. Slutsats: För en bra samverkan vid omhändertagande av patienter krävs god kommunikation mellan samtliga aktörer, mer utbildning och övningar samt utveckling av befintliga rutiner och riktlinjer.

  • Mushtaq, Irrum
    et al.
    Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Akhter, Zareen
    Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
    Shah, Faiz Ullah
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Tunable Self-Assembled Nanostructures of Electroactive PEGylated Tetra(Aniline) Based ABA Triblock Structures in Aqueous Medium2019In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 7, p. 1-10, article id 518Article in journal (Refereed)
    Abstract [en]

    PEGylated tetra(aniline) ABA triblock structure PEG-TANI-PEG (2) consisting of tetra(aniline) (TANI) and polyethylene glycol (PEG) was synthesized by coupling the tosylated-PEG to boc-protected NH2/NH2 TANI (1) through a simple nucleophilic substitution reaction. Deprotection of 2 resulted in a leucoemeraldine base state of TANI (2-LEB), which was oxidized to stable emeraldine base (2-EB) state. 2-EB was doped with 1 M HCl to emeraldine salt (2-ES) state. FTIR, 1H and 13C NMR and UV-Vis-NIR spectroscopy, and MS (ESI) was used for structural characterization. The synthesized triblock structure exhibited good electroactivity as confirmed by CV and UV-Vis-NIR spectroscopy. Self-assembling of the triblock structure in aqueous medium was assessed by DLS, TEM, and SEM. Spherical aggregates were observed with variable sizes depicting the effect of concentration and oxidation of 2-LEB. Further, the aggregates showed acid/base sensitivity as evaluated by doping and dedoping of 2-EB with 1 M HCl and 1 M NH4OH, respectively. Future applications in drug delivery and sensors are envisaged for such tunable self-assembled nanostructures in aqueous media.

  • Enochsson, Ola
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering. Bodens kommun, Sverige.
    Elfgren, Lennart
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Johansson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Ojanen, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Emborg, Mats
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Tillståndsbedömning av järnvägsbro över Byske älv vid Myrheden, Bandelen Bastuträsk – Nyfors, km 1031+9372010Report (Refereed)
    Abstract [sv]

    Järnvägsbron över Byske Älv vid Myrheden är en bågbro av betong som färdigställdes 1941. Bågen har en spännvidd av 39,2 m och den totala längden är 59,6 m. Bågen blev fläckvis frysskadad i samband med gjutningen och har reparerats med ca 10 års mellanrum. År 2003 upptäcktes ånyo betongskador i underkant på bågen. Den dåliga betongen bilades bort och ersattes med torrbruk som sprutades på plats. Efter reparationen bedömdes bron kunna klara tåglast BV-2 (25 tons axellast och 7,2 ton/m utbreddlast). För att bedöma brons fortsatta livslängd och bärförmåga har Avd för Byggkonstruktion vid LTU tagit del avtidigare tillståndsbedömningar och besiktigat bron 2009-02-13 och 2009-08-25--26. Bron visade sig vara i förhållandevis gott skick. Vi bedömer att den kan klara tåglast BV-2 i ytterligare fem år under förutsättning att den hålls under uppsikt och att en närmare utredninggörs av gjutfogarna i bågen under skivstöden och av skivstödens ledformade anslutningar mot bågen. Bron borde hålla i 20 år eller mer om ballasten rensas från finare grusfraktioner så att dräneringen förbättras. Vattenavledningen från bron bör vidare ordnas så att vatten från brobanan förhindras rinna ner längs bågen och bidra till frost- och korrosionsangrepp. Dessutom bör dålig/skadad betong vattenbilas bort och ersätts med pågjutning av ny betong.