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  • Englund, Othilia
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science. Kvinna.
    It-branschens utmaningar och förändringar med att rekrytera in kvinnor: en kvalitativ studie om hur kvinnor upplever det att arbeta inom IT-branschen2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis analyze how the IT-industry can work to recruit more women into the industry. The analyze will occur by investigating how women experiencing the feeling of working in the industry, an industry that’s dominated by men, only 28% of the industry has women as employees, at the same time as it’s an industry dominated in the Swedish workforce, by the year of 2015 it had a turnover of 647 100 million Swedish crowns. An industry whit that much in turnover shows the power of workforce. That the IT-industry is main dominated by men, makes a segregation between women and men, where each sex should work and where women spare to be able to work in the Swedish working life. At the same time as less equal organizations and branches creates negative organizational cultures like macho cultures and reproduction of male dominance.

     

    The theoretical point of the thesis is organizational cultures, power in organizations, gender, masculinity, reproduction of male dominance, equal and exclusion in organizations, gender in organizations and concepts of the phenomenon culture. The thesis includes previously scientific articles on organizations, organizational cultures and women in the IT-industry.

     

    The study is based on qualitative ground, where 17 women working in the IT-industry shares their view and experiences of working in the industry. The 17 women have different positions in the It-industry, some have academic backgrounds, and some respondents are self-learned in the spectra of IT. The methodological point is based on the knowledge of sociology by Luckmann and Berger (1966).

     

    The result of the thesis shows that the industry has many challenges as women faces to work in the IT-industry. Challenges in claiming and aiming for their competence, struggles in being in cultural challenges, male dominance and negative organizational cultures. The competence that women have, is being taken seriously, but yet challenged and questioned, by male colleagues. Organizational cultures that seems to establish because of the male dominated industry and organizations. The thesis shows that men have more power in which organizational cultures that shall be obtained in organizations, at the same time as men seems to recruit men. Which causes reproduction of the negative organizational cultures issues that comes with the male dominated IT-industry, cultures as macho-culture and “mate-culture” becomes visible. The result of the thesis show that the industry must do some changes to be able to recruit more women into the industry. Changes in working out the outdated picture of what it means to work in the industry and changes in visible the women who already works in the IT-industry. HR and the whole industry shall work more to create and equal industry, where as many women as men works, where both men and women feel welcomed.

  • Jonsson, Jessica
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Wisten, Gabriella
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Patienters upplevelse av bemötandet i hälso- och sjukvården vid psykisk ohälsa - En litteraturstidie2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • Samuelsson, Amanda
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Nilsson, Yuleidy
    Luleå University of Technology, Department of Health Sciences.
    Erfarenheter hos sjuksköterskor inom barnhälsovården av att möta föräldrar till barn med övervikt2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • Olofsson, Sofia
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Lilja, Felicia
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Faktorer som kan leda till att sjuksköterskor avsiktligt lämnar arbetsplatsen eller professionen – en integrerad litteraturöversikt2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Introduktion: En åldrande befolkning, sjukdomsmönster som förändras och en ökad befolkning kommer att öka efterfrågan på sjukvårdspersonal 15 år framåt. Trots att tillväxten ökar beräknas det vara ett underskott på 9,9 miljoner vårdpersonal globalt år 2030, vilket inte kommer täcka det framtida hälsobehovet hos befolkningen. Omvårdnaden och vårdkvalitet kan äventyras när sjuksköterskor säger upp sig, då det blir färre sjuksköterskor i förhållande till antalet patienter. Att arbeta underbemannat kan leda till en stressad arbetsmiljö, som in sin tur kan leda till att fler olyckor sker, både bland patienter och sjuksköterskor. Syfte: Syftet med denna litteraturöversikt var att sammanställa kunskap om vilka faktorer som kan leda till att sjuksköterskor avsiktligt lämnar arbetsplatsen eller professionen. Metod: För att besvara syftet genomfördes en integrerad litteraturöversikt, som tillåter både kvalitativa och kvantitativa studier. Utifrån syftet söktes vetenskapliga artiklar i tre databaser; PubMed, Cinahl och PsycINFO. Artiklarna kvalitetsgranskades och analyserades genom en integrerad litteraturöversikt. Resultat: Analysen resulterade i två kategorier, faktorer inom organisationen och personliga faktorer. Faktorer inom organisationen innefattar fyra undergrupper, arbetsmiljö, ledarskap och belöningar, medarbetare och vårdmötet. Personliga faktorer innefattar två undergrupper, engagemang och erfarenhet och psykisk och fysisk ohälsa. Slutsatser: De enskilda faktorerna som påverkar sjuksköterskans avsikt att lämna arbetet eller professionen går in i och påverkar varandra. Ledare, chefer och enskilda sjuksköterskor kan arbeta tillsammans för att påverka dessa faktorer. Detta kan bidra till att sjuksköterskor väljer att stanna kvar på arbetsplatsen och i professionen.

  • Andersson, Erik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Preliminary design of a small-scale liquid-propellant rocket engine testing platform2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Propulsion system testing before mission operation is a fundamental requirement in any project. For both industrial and commercial entities within the space industry, complete system integration into a static test platform for functional and performance testing is an integral step in the system development process. Such a platform - if designed to be relatively safe, uncomplicated and reliable - can be an important tool within academia as well, giving researchers and students a possibility for practical learning and propulsion technology research.

    In this thesis, a preliminary design for a liquid-propellant rocket engine testing platform to be used primarily for academical purposes is developed. Included in the presented design is a bi-propellant Chemical Propulsion system, gas pressure fed with Gaseous Nitrogen and using Gaseous Oxygen as oxidiser and a 70 % concentrated ethanol-water mixture as fuel. The propellant assembly contains all necessary components for operating the system and performing combustion tests with it, including various types of valves, tanks and sensors. An estimation of the total preliminary cost of selected components is presented as well. Also part of the developed platform design is a small thrust chamber made of copper, water-cooled and theoretically capable of delivering 1000 N of thrust using the selected propellants.

    A list of operations to be performed before, during and after a complete combustion test is presented at the end of the document, together with a preliminary design of a Digital Control and Instrumentation System software. Due to time limitations, the software could not be implemented in a development program nor tested with simulated parameters as part of this thesis project.

  • Andreas, Berglund
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Production Development: Layout Project at Lundqvist Trävaru AB2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of the master thesis has been to examine the production system at the company Lundqvist Trävaru AB and use the gathered information to create a layout suggestion together with a couple of improvement ideas. The thesis is the final part of the Industrial Design Engineering programme at Luleå University of Technology (LTU). Lundqvist Trävaru AB is a manufacturing company that specializes in producing prefabricated building kits out of wood, but the insufficient size of their current factory located in the industrial area of Öjebyn on the outskirts of Piteå, have created a need to relocate to alarger site. This new site is located at Haraholmen south of Piteå. The aim and objective have therefore been to develop a layout suggestion as well as a couple of improvement ideas, with the purpose of solving the identified problems at the current factory, thereby making sure that they do not reappear at the new site.

    Methods in the form of interviews, observations and documentation reviews were performed to identify potential problems with the production system and the work organization. To aid the investigation of the current factory, literature reviews of scientific books and articles were also performed during the project, with the purpose of giving the thesis a solid scientific foundation. After an overview of the production system had been created, the next step was to analyze the identified problems. These affected many different aspects of the company, for instance the material handling, work organization, flow ofinformation, production flexibility, inventory capacity and production flow. The main problem that in turn caused many of the identified problems was the insufficient inventory capacity, which led to problems with overflowing inventories and long delivery times for materials. This in turn affected thematerial handling negatively and made it hard to keep track of materials in the factory. 

    Additional problems that were identified was divided workstations, scattered areas for material storage, an increasing amount of special orders with dimension outside of the ordinary size range, a lack of standardized working methods and lack of communication between the office and the production team. After the problems had been identified, the next part of the project was dedicated to performing creative methods with the purpose of developing layout concepts as well as improvement ideas. The methods that were used to fulfill this task was brainstorming, mind map, requirement specification, proximity chart and workshop. After these methods had been performed the result was four layout concepts and several improvement ideas. 

    The next step was to evaluate the layouts and the ideas with the help of the requirements that had been specified together with the management at Lundqvist. The evaluations resulted in a final layout together with the most promising improvement ideas. These ideas were to standardized drawings and working methods, increase the work with creating manuals for the different stations and machines, adapt the workstations for special orders, purchase tablet computers for each workstation thereby allowing better information sharing and contact between the production team and the office, create a digital map of the factory, use markings and colors at inventories to facilitate identification of specific materials, better routines for the disposal of production waste and larger passages for trucks and wheel loaders.

    The result of the last part of the project was a 3D-model of the factory and the site, which showed the placement of the different machines, workstations and inventories used during the production of the prefabricated building kits. The benefits of the suggested layout and improvement ideas are bettermaterial handling, increased inventory capacity, better information sharing, standardized working methods and drawings, a straighter production flow and an increased production flexibility, which gives a better ability to produce special orders. If it turns out that it is hard to implement the layout at thepresent, the recommendation for Lundqvist Trävaru AB is to start with implementing the improvement ideas and then successively implement the layout. The suggested ideas and layout will make the company more prepared for the future and increase their ability to handle the planned productionincrease, while also making sure that they are able to better keep production deadlines, attract more customers and successfully establish themselves at Haraholmen. Which in turn will lead to reduced unemployment and increased tax revenue for Piteå municipality

  • Wirsenius, Mattias
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Fjärde generationens fjärrvärme och samförläggning vid Kiruna stadsomvandling: Ett samarbete mellan LTU och Tekniska Verken i Kiruna AB2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    En tredjedel av Kirunas stad är på väg att flyttas och med det kommer nya möjligheter för en utveckling av den nya stadsdelen. Kiruna stad vill bygga ett attraktivt och hållbart samhälle som utnyttjar ny teknik för en energi- och resurssmart stadsmiljö. Fjärde generationens fjärrvärme eller 4GDH som det oftast förkortas är ett koncept som tagits fram för att öka fjärrvärmens konkurrenskraft samt öka dess attraktivitet för kunder.

    Detta projekt har genomfört en utredning för 4GDH i ett område i nya Kiruna där värmeprofiler har tagits fram med hjälp av CFD-programmet Comsol och en teknoekonomisk analys har utförts där olika alternativ på 4GDH jämförs mot varandra och mot den traditionella fjärrvärmen som finns idag. En ny teknik har undersökts som benämns samförläggning vilket innebär att flera tekniker förläggs i samma schakt.

    I rapporten redovisas viktiga resultat från simuleringar över nätet i Comsol, där hastigheter, temperaturfall och termiska förluster tas fram för flera olika varianter på nätets dimensionering för att sedan jämföras för att hitta det bästa alternativet. Den teknoekonomiska analysen visar att 4GDH är att föredra framför traditionell fjärrvärme med en besparing på drygt 3 miljoner kronor sett över rörens livslängd på 50 år.

  • Kärrman, Victoria
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    The effects of the Swedish moosemanagement2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study was to examine the effects on the Swedish moose populationof a new moose management system introduced in 2012. To this end, the size of thepopulation had to be measured. The methodology used was an empirical version of theGordon–Schaefer bioeconomic model previously employed to estimate Sweden’s wildboar population. The Effort variable for the model was modified in that traffic accidentsrelative to traffic density served as a proxy for it. The study investigated years for whichdata was available, namely 2004–2017. Nineteen out of Sweden’s 21 Counties wereincluded in the study. The result produced extremely high population estimates,suggesting that the model could not be directly transferred from wild boar to moose.Nonetheless, although the study’s population estimates in absolute terms are unrealistic,their relative sizes indicate that moose populations were somewhat smaller in 2017 thanin 2012 – the latter year being when the new management system was introduced.However, the trend line shows that, over a longer period, the moose population hasincreased in Sweden, and 2017 may just be a temporary deviation from that trend. Itappears, therefore, that Sweden’s latest moose management system does not have thedesired effect on its moose population.

  • Öberg, Oskar
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Critical Branching Regulation of the E-I Net Spiking Neural Network Model2019Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Spiking neural networks (SNN) are dynamic models of biological neurons, that communicates with event-based signals called spikes. SNN that reproduce observed properties of biological senses like vision are developed to better understand how such systems function, and to learn how more efficient sensor systems can be engineered. A branching parameter describes the average probability for spikes to propagate between two different neuron populations. The adaptation of branching parameters towards critical values is known to be important for maximizing the sensitivity and dynamic range of SNN. In this thesis, a recently proposed SNN model for visual feature learning and pattern recognition known as the E-I Net model is studied and extended with a critical branching mechanism. The resulting modified E-I Net model is studied with numerical experiments and two different types of sensory queues. The experiments show that the modified E-I Net model demonstrates critical branching and power-law scaling behavior, as expected from SNN near criticality, but the power-laws are broken and the stimuli reconstruction error is higher compared to the error of the original E-I Net model. Thus, on the basis of these experiments, it is not clear how to properly extend the E-I Net model properly with a critical branching mechanism. The E-I Net model has a particular structure where the inhibitory neurons (I) are tuned to decorrelate the excitatory neurons (E) so that the visual features learned matches the angular and frequency distributions of feature detectors in visual cortex V1 and different stimuli are represented by sparse subsets of the neurons. The broken power-laws correspond to different scaling behavior at low and high spike rates, which may be related to the efficacy of inhibition in the model.

  • Danielsson, Tone
    Luleå University of Technology, Department of Health Sciences, Health and Rehabilitation.
    LEGO® terapi - en arbetsterapeutisk intervention?2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • Sjöstrand, Philip
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    New bogie suspension concept2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    There is always a desire to develop and offer the best and most protable products on the market. This master thesis in mechanical engineering investigates the possibility to reduce the costs of the bogie suspension on Volvo's articulated haulers. The so called stays in the existing bogie suspension are significant components that connects the axle housings to the frame. The existing solution consists of stays that are expensive, heavy and time consuming to manufacture. Concepts in CAD will be compared to each other and and all concept will be evaluated in more detail.

    Totally five concepts were generated and modelled. They were compared regarding strains on rubber parts, required stay dimensions, collision between different parts and axle movements. Two proceeded concepts for further development after the evaluation and two new concepts were generated. A new comparison was made with additional tests.

    Simulations conrmed that it was only possible to proceed with one of the two developed concepts because one of the concepts would require large dimensions to manage the applied forces. The selected concept was redesigned and adapted to be as realizable as possible. Bushing kits, reinforcements, and detailed designs of parts were considered. Simple FEMcalculations was only made on parts that wasn't depending on components on the frame since these calculations would be too advanced and time consuming. The resulting concept needs more work to be realizable since there are geometry optimization on molded components left as well as advanced calculations when integrating the solution on the frame. A weight loss ofapproximately 95kg and a cost reduction of 3700SEK was made. Further investigations has to be done to determine if it's possible to obtain a positive business case with the new bogie suspension.

  • Valilla, Jorge
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Thermal characterization and comparison of different advanced composites for tooling applications2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The aim of this study if to give a comparison between different kind of high composite laminates (thin ply and conventional thickness plates) for tooling applications. The study mainly deals with the thermal behaviour of these materials after certain amount of time of exposure, and how this can affect the mechanical properties. This approach was chosen since thermal properties are of the biggest challenges when creating reliable parts to make tools.The study also serves as a deeper insight into the thin-ply laminates, how they work and give further characterization, since these are still novel technologies which have not reach the highest potential.The project was carried out within the Polymer and Composite division at Luleå University of Technology and is part of ongoing work of the Eureka platform (TOOLS) in collaboration with Airbus Spain as well as other institutes such as Swerea SICOMP Ab, Corebon Ab, Loiretech Mauves, Rise Acreo Ab and Lund University.

  • Dhakal, Nayan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Tribology of newly developed EAL versus water in hydropower turbine bearings2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The increasing demand for more readily bio-degradable, renewable and non-toxic environmentally adaptive lubricants with a lower degree of bioaccumulation has escalated the investigation of water-based lubricants as the potential alternatives for conventional mineral-based oils. Water is an excellent environmentally adapted lubricant; however, it is a low viscous fluid and holds downsides of having corrosive nature and extremely low pressure-viscosity coefficient leading to insufficient load-carrying capacity. These shortcomings make pure water a poor choice for operations involving high load and low speed, for instance, within hydropower applications. Therefore, the choice of appropriate modifiers and additives is crucial to improve the viscosity, friction-reducing performance and anti-wear properties of water as a base lubricant. Appropriate selection and combination of bearing materials also significantly improve the tribological performance of the lubricants. In the presented work, tribological behavior of polyvinylpyrrolidone (PVP) and poly(sodium 4-styrenesulfonate) (PSS) thickening agents with water as a base fluid in the lubrication of pure UHMWPE and SCF reinforced UHMWPE bearing materials has been investigated individually under reciprocating tribometer. The results showed that both PVP and PSS are excellent viscosity modifiers. PVP exhibited excellent friction-reducing and anti-wear performance, while PSS revealed increased wear rates with an insignificant reduction of friction coefficients. This study aims to explore the potential for using newly developed water-based lubricants in the replacement of traditional mineral-based lubricants for hydropower turbine bearings.

  • Kerttula, Matheus
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Lindberg, Daniel
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Distriktssköterskors erfarenheter av att främja fysisk aktivitet hos fysiskt inaktiva personer2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    District nurses’ reliability is high in society and therefore they are in an position to act as a leader in the health promotion work. It’s been shown that there’s obstacles to promoting physical activity and there are few studies of experiences of district nurses’ regarding the promotion of physical activity Aim The purpose of this study was to illustrate distict nurses’ experiences of promoting physical activity in physically inactive persons Method Data collection was carried out through semistructured interviews in which eight district nurses’ were interviewed. Data was analysed with thematic content analysis. Results One theme: to face challenges and four categories emerged; To personalize the conversation and activity; To work with evidence-based tools; To meet obstacles in the health promotion work and That good knowledge simplifies the health promotion work Conclusion An increased amout of time is needed to promote physical activity in a greater extent. Health promotion work is not prioritized by organizations because of not enough time is not set aside for this. The work could be seen as challenging but was considered important. Education within MI is needed to strengthen the promotion work

  • Lagrama, Kimberly Rose
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Friction and Wear Performance of Experimentally Developed Self-lubricating PPS/PTFE Composites2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Demanding applications, as well as the push to eliminate the need for fossil-fuel based lubricants, create the need for the development of high-performance polymers.

    Polyphenylene Sulfide (PPS) is an example of a high-performance polymer and has a high service temperature, good dimensional stability, and excellent chemical resistance. However, it has a low impact strength and is very brittle in neat form. Another high-performance polymer, Polytetrafluoroethylene (PTFE), provides low friction in dry sliding conditions and can deposit polymer transfer films onto the counterface but exhibits high wear rates in neat form.

    To take advantage of the desirable characteristics of both polymers, PPS/PTFE-based composites were produced through the Injection Molding process. The individual disadvantages of these polymers were further improved by incorporating the following fillers: SCF, GO and CNT. The tribological performance under dry sliding conditions and two different loads were investigated as well as the microhardness and degree of crystallinity of the materials.

    The DSC results showed that the incorporation of reinforcements did not significantly alter the total degree of crystallinity in the material. PPS/PTFE and the composites have significantly lower specific wear rates and coefficient of friction values compared to neat PPS and PTFE. The composites have higher microhardness and friction coefficient values (60N and 100N) compared to PPS/PTFE. For both loads, composites SCFCNT, 5SCF and 10SCF had the lowest specific wear rates recorded where a synergistic effect between SCF and CNT has been observed.

    The filler loading content did not affect the friction performance of the composites in both loads. However, for composites with SCF as the only reinforcement, the increase in wt% content of SCF increased the specific wear rate at 60N and decreased the specific wear rate at 100N.

    SEM images of the pin surfaces show that the governing wear mechanisms in the polymer blend and composites are abrasive and adhesive wear. The reduction of the specific wear rate values is also accompanied by the improvement in the uniformity of the observed transfer film formation.

  • Markus, Gustafsson
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Energier och CO2, fördelning i flödet vid mobil krossning2019Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [en]

    Due to new laws and the company’s own initiative concerning tracking of energies and emissions in quarries, NCC has begun surveying these factors. For their smaller quarries they mean to produce a method for local site managers, with which they themselves can perform this task. Because of these reasons the study in this rapport has been done. The end goal was to study the amount of available informtion about the energies at Eker quarry. Then Using this information to create a method for site managers to simplify their work as well as performing a survey in Eker concerning energies and emissions per ton of produced materials during 2018. The end product was an excel-file that calculates och distributes energies and emissions as long as data about used diesel and electricity is entered into the file. The survey produced the key figures for energies, 10,03 kWh/ton for the total 4,82 kWh/ton for products after the first crusher stage, 7,74 for products after the second and 14,25 kWh/ton for products after the third crusher stage. The key figures for emissions are 2,39 kg CO2/ton for the total, 1,05 kg CO2/ton for products after the first crusher stage, 1,80 for products after the second and 3,49 kg CO2/ton for products after the third crusher stage. The results show the possibilities to perform this type of survey with the produced method. The survey’s limitations were at the preliminary work with salvoes and ended when the product was loaded to a customer. Only the major factors of diesel and electricity was studied.

  • Hasan, Hasan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Detaljkonstruktion av tvättmaskin för anodpåsar2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The silver refining process is a extracting of pure silver which happen in large tanks filled with silver nitrate electrolyte solution. In each tank there are 6 Doré anodes, where they are placed in anode bag. During the refining process, the remaining products are gold, palladium and platinum which are formed to a kind of sludge in the anode bags. Outotec Sweden AB (Outotec) therefore wanted a structure that can clean the anode bags and at the same time save the sludge. To get a good solution that needs to start with understanding of the silver refining process and meetings with customers and engineers from Outotec Sweden AB. Thereafter, two concepts based on the requirements specification are processed and presented, in order to clarify the objective. With the help of CAD programs, one concept is then constructed into a strong, reasonable and simple prototype. Tensions and deflections are also calculated to confirm the model's strength and thus ensure that the design will hold for the load. Risk analysis is also carried out to develop the prototype and facilitate the production and development process.

  • Svensson, Philip
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Översikt av nätverk på LEAB: analys, uppdatering av dokumentation och förbättringsförslag2019Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
  • Al-Jabban, Wathiq
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Laue, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    A Comparative Evaluation of Cement and By-Product Petrit T in Soil Stabilization2019In: Applied Sciences: APPS, ISSN 1454-5101, E-ISSN 1454-5101, Applied Sciences, Vol. 9, no 5238Article in journal (Refereed)
    Abstract [en]

    This study presents a comparison between the effectiveness of adding low binder amounts of industrial by-product Petrit T as well as cement to modify and improve fine-grained soil. Binder amount was added by soil dry weight; cement at 1%, 2%, 4% and 7% and Petrit T at 2%, 4% and 7%. The unconfined compressive strength (UCS) was used as an indicator of soil strength. In addition, the consistency limits, laser particle size analysis, and pH tests were also conducted on the treated soil. The samples were cured at 20 °C for different periods from 7 to 90 days before testing. Results indicate that cement is more effective at improving the physical and engineering properties of the treated soil. Soil plasticity index decreases after treatment and with time. Liquidity index and the water content to plastic limit ratio are introduced as new indices to define the improvement in the workability of treated soil. Soil particle size distribution is changed by reducing the clay size fraction and increasing the silt size fraction after treatment. The findings confirm that adding small binder contents improve soil properties, which subsequently reduce the environmental threats and costs that are associated with using a high amount of binder.

  • Myhr, David (Singer, Musician)
    Every Raindrop Means A Lot2019Artistic output (Unrefereed)
    Abstract [sv]

    HYLLNINGSSKIVA TILL TAGES, SVERIGES BÄSTA 60-TALSBAND

    17 nutida artister och band tolkar legendariska Tageslåtar digitalt, på CD och vinyl. 

    Allt från jättehiten Sleep Little Girl och Every raindrop means a lot till mästerverket Fantasy Island.

    Några av de som medverkar är Peter Morén (från Peter Bjorn & John), Max Lorentz, David Myhr, Soundtrack of Our Lives och det amerikanska bandet Anderson Council.

    Idén till albumet fick Göran Brandels, från Mariestad, 2014 då två av medlemmarna i Tages avled och ingen mer återförening kan ske. Musiken får inte glömmas bort. Låtarna är så bra och håller än idag. Tillsammans med Eskilstunabon Peter Torsén drog de igång projektet med att låta några av dagens artister och band tolka Tages musik.

  • Hossain, Mohammad Shahadat
    et al.
    University of Chittagong, Bangladesh.
    Tuj-Johora, Fatema
    University of Chittagong, Bangladesh.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A Belief Rule Based Expert System to Assess Hypertension under Uncertainty2019In: Journal of Internet Services and Information Security (JISIS), ISSN 2182-2069, E-ISSN 2182-2077, Vol. 9, no 4, p. 18-38, article id 2Article in journal (Refereed)
    Abstract [en]

    Hypertension (HPT) plays an important role, especially for stroke and heart diseases. Therefore, theaccurate assessment of hypertension is becoming a challenge. However, the presence of uncertainties, associated with the signs and symptoms of HPT are becoming crucial to conduct the preciseassessment. This article presents a web-based expert system (web BRBES) by employing beliefrule based (BRB) methodology to assess HPT, allowing the generation of reliable results. In order tocheck the reliability of the system, a comparison has been performed among various approaches suchas decision tree, random forest, artificial neural networks, fuzzy rule based expert system and experts’opinion. Different performance metrics such as confusion matrix, accuracy, root mean square error,area under curve have been used to contrast the reliability of the approaches. The BRBES producesa more reliable result than from the other approaches. Moreover, the user friendliness of the webBRBES found high as obtained by using the PACT (People, Activities, Contexts, Technologies) approach over 200 people.

  • Alabidi, Abdulkadhim J.
    et al.
    Department of Geology, Faculty of Science, University of Kufa, Kufa, Iraq.
    Al-Dahaan, Saadi A. M.
    Department of Geology, Faculty of Science, University of Kufa, Kufa, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Fire and Smoke Phenomenon in West Najaf City: Southwest Iraq2019In: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 11, no 12, p. 791-800Article in journal (Refereed)
    Abstract [en]

    A strange phenomenon of fire taking place at Arruhban area west Bahr-Al Najaf area in Iraq was noticed in 2010 and smoke continued many months; this phenomenon reappeared many years later. This site is part of Bahr-Al Najaf-Iraq NE Arabian plate, located in flat area near an archeological site of Christian temple called Tel Arruhban. To understand the causes for this fire in a non-residential area, field observations from repeated visits between 2010 and 2018 and on-site excavation operations were conducted. The results of analysis of soil samples, and on-site detection for gases and vapors showed that the phenomenon of burning and smoke generated at this site was due to external influences and that the presence of soil rich with organic materials helped to the existence of this phenomenon.

  • Alwan, Khaldoon Khaled
    et al.
    Department of Geology, College of Science, University of Baghdad, Iraq.
    Al-Kubaisi, Manal Shakir Ali
    Department of Geology, College of Science, University of Baghdad, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Validity of Existing Rain Water Harvesting Dams within Part of Western Desert, Iraq2019In: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 11, no 12, p. 806-818Article in journal (Refereed)
    Abstract [en]

    The study area is located within the western part of Iraq between Latitude

    (32˚45'0'' - 34˚0'0'') North and longitude (39˚30'0'' - 40˚45'0'') East within

    Anbar Governorate. It covers an area of 4767.423 Km 2 with elevation ranges

    from 360 to 840 m. The general slope decreases from southwest to northeast.

    Five old dams identified in the study area. The results of SWAT model

    showed high curve number (70 - 85) indicating low filtration and runoff rate

    (1.2 - 8.2) mm for the period (1994-2014). These dams have catchment areas

    ranged between (118.03 - 673.41) km 2. They were to be used for agricultural

    purposes. The results according to the Food, Agriculture Organization (FAO)

    standards for their distance from agricultural areas using a GIS showed that

    all are not suitable except dam number (1). The distance to roads showed that

    dams (1, 4) are highly suitable, (2, 3) are low suitable and dam (5) is not suitable.

    The average annual quantity of rain water that can be harvested from

    the 5 dams is about 12.9 million cubic meters.

  • Maligranda, Lech
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Pierwsze trzy Zjazdy Matematyków Polskich PTM: 1927, 1931, 19372019In: Wiadomosci Matematyczne, ISSN 2080-5519, Vol. 55, no 1, p. 15-27Article in journal (Refereed)
    Abstract [en]

    Polish Mathematical Society (PTM) was founded in 1919. The society's statute defined its purpose as comprehensive cultivation of pure and applied mathematics by holding scientific meetings with talks, publishing periodical journals and papers with mathematical content and maintaining communication with the mathematical scientific movement abroad. In 1929, 176 members belonged to the Society, of which 147 were ordinary members. Mathematicians from other countries also belonged to the Society; in 1929 there were 29 foreign members and in 1939 - 51 foreign members. More detailed descriptions of the creation and activity of PTM can be found in [8-10, 14, 16, 18-23]. The General Assembly of PTM on 2 April 1926 in Krakow decided to convene the first Polish mathematical congress, and the first information about the congress appeared in [17]. The congress was organized by the Lvov Branch in 1927. This article discusses this Congress and two further Congress of Polish Mathematicians before 1939.

  • Maligranda, Lech
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Władysław Orlicz w Getyndze: 1928-19302018In: Wiadomosci Matematyczne, ISSN 2080-5519, Vol. 54, no 2, p. 191-219Article in journal (Refereed)
    Abstract [en]

    Trips by Polish mathematicians to Göttingen, an important center of mathematics, in the period of annexations and after independence in 1918, were of great importance for their scientific development. In the years 1895-1933 it was over thirty mathematicians, and among them Władysław Orlicz, who stayed at the University of Göttingen from December 1928 to August 1930 (with breaks for stays in Lvov). We describe about his stay in Göttingen and his mathematical achievements obtained during his stay there.

  • Skog, Torkel
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    CuPGS Laminate Core for a Matrix Microchannel Heat Exchanger2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Cryocooling is a continuously developing field of engineering, applied in the fieldsof aerospace, military, and medical sciences among others. There is a demand forsmaller and more efficient cryocoolers for spaceborne low-light observation missions,with many custom cooling systems having completed successful missions. The Stir-ling cycle is the most prevalent refrigeration technique used for space applications,with the pulse-tube, Joule-Thomson or reverse Brayton cycles being used in somespecial cases.A matrix heat exchanger is designed with 3D-printed 17-4 PH stainless steel end capsstreamlined for computer numerical control (CNC) production.

    The heat exchanger (HX) core consists of 1mm thick stainless steel spacers and 250μm thick copperchips that are tolerance-matched for photo etching, as well as pyrolytic graphitesheets (PGS) of 25μm, the thickest commercially available PGS without addedadhesive film material.The experiments of joining PGS and copper chips with Epo-Tek 301-2 epoxy tocreate a solid core structure for the heat exchanger did not result in a pressure-resistant laminate material. The graphite surface proved difficult to adhere to usingthis epoxy, creating voids, and easily delaminated into separate layers of PGS. Bond-ing the stack together using indium, testing epoxy with a higher ability to permeatethe PGS or diffusion-bonding through other means are presented as options forfurthering the HX development.Pressure testing of a copper-only laminated heat exchanger core showed that theend cap recess adhesion capability is a potential point of failure, as the designedstructure makes it impossible to inspect the results of the bond without curingthe epoxy and pressurising the system. The difficulty in establishing a tight seambetween the main counter-flow channels of the HX is also demonstrated here, asleakage between the channels occurred at pressures in the vicinity of 2

  • Ek, Robert (Musician)
    Luleå University of Technology, Department of Arts, Communication and Education, Music and dance.
    In and around Berlin: concert during HCMF 2019, Huddersfield Contemporary Music Festival2019Artistic output (Unrefereed)
  • Neely, Gregory
    et al.
    Department of Psychology, Umeå University, Umeå, Sweden.
    Sörman Eriksson, Daniel
    Department of Psychology, Umeå University, Umeå, Sweden.
    Körning-Ljungberg, Jessica
    Department of Psychology, Umeå University, Umeå, Sweden, .School of Psychology, Cardiff University, Cardiff, United Kingdom.
    The impact of spoken action words on performance in a cross-modal oddball task2018In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 13, no 11Article in journal (Refereed)
    Abstract [en]

    In this study a cross-modal oddball task was employed to study the effect that words spokeneither non-urgently or urgently would have on a digit categorization task and if women wouldexhibit greater behavioral inhibitory control. The words were unrelated to the task itself, butrelated to the action required to complete the task. Forty participants (21 women) conducteda computerized categorization task while exposed to a sinewave tone as a standard stimulus(75% of the trials) or a to-be ignored word (press, stop) spoken either non-urgently orurgently as unexpected auditory deviant stimulus (6.25% trials for each category). Urgentwords had sharp intonation and an average fundamental frequency (F0) ranging from 191.9(stop) to 204.6 (press) Hz. Non-urgent words had low intonation with average F0 rangingfrom 103.9.9 (stop) to 120.3 (press) Hz. As expected, deviant distraction and longerresponse times were found by exposure to the word stop, but deviant distraction was notfound to be significant with the word press or due to intonation. While the results showedthat women had in general longer reaction times, there were no gender differences foundrelated to the deviant distraction caused by word or intonation. The present results do notsupport the hypothesis that women have greater behavioral inhibitory control, but there wasevidence that the meaning of the word could influence response times.

  • Broekhuizen, Ico
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Muthanna, Tone M.
    Norwegian University of Science and Technology, Trondheim, Norway.
    Leonhardt, Günther
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Urban drainage models for green areas: Structural differences and their effects on simulated runoff2019In: Journal of Hydrology X, ISSN 2589-9155, Vol. 5, article id 100044Article in journal (Refereed)
    Abstract [en]

    Mathematical stormwater models are often used as tools for planning and analysing urban drainage systems. However, the inherent uncertainties of the models must be properly understood in order to make optimal use of them. One source of uncertainty that has received relatively little attention, particularly for increasingly popular green areas as part of urban drainage systems, is the mathematical model structure. This paper analyses the differences between three different widely-used models (SWMM, MOUSE and Mike SHE) when simulating rainfall runoff from green areas over a 26-year period. Eleven different soil types and six different soil depths were used to investigate the sensitivity of the models to changes in both. Important hydrological factors such as seasonal runoff and evapotranspiration, the number of events that generated runoff, and the initial conditions for rainfall events, varied significantly between the three models. MOUSE generated the highest runoff volumes, while it was rather insensitive to changes in soil type and depth. Mike SHE was mainly sensitive to changes in soil type. SWMM, which generated the least runoff, was sensitive to changes in both soil type and depth. Explanations for the observed differences were found in the descriptions of the mathematical models. The differences in model outputs could significantly impact the conclusions from studies on the design or analysis of urban drainage systems. The amount and frequency of runoff from green areas in all three models indicates that green areas cannot be simply ignored in urban drainage modelling studies.

  • Brunnacker, Lena
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Short Carbon Fiber-Reinforced Thermoplastic Composites for Jet Engine Components2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    State-of-the-art aircraft engine manufactures aim to reduce theirenvironmental impact steadily. Thereby they attempt to increase engineefficiency, use new renewable fuel sources and most importantly aim toreduce component weight. While Titanium, Aluminum and continuousfiber reinforced thermosetting composites and superalloys prevail in thecurrent material selection, the present work desires to raise awareness fora novel group of materials; short carbon fiber reinforced thermoplasticcomposites (SCFRTPs). In this kind of composite short fibers givedimensional stability and strength while the thermoplastic matrix ensuresthe physical properties, even at temperatures up to 300°C.Even though in some applications these materials offer great potential tosave weight and cost, it is not clear if their properties suffice to be used indemanding areas of the aero engine and if they are still able provide costand weight reductions there.The present work therefore investigated potential aero-engine componentsthat could be replaced by SCFRTPs. With literature, manufacturer data andmaterial and process modelling approaches, it is shown that SCFRTPsmechanical and physical properties suffice for the selected component.Further it is shown that cost reductions up to 77% and weight savings upto 67% compared to the Ti-6Al-4V baseline component are possible.

  • Englund, Mia
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Fjellström, Lina
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Minskad personalomsättning med hjälp av intern employer branding: En fallstudie om hur ett känt företag inom telekombranschen kan minska personalomsättningen av kundtjänstmedarbetare2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A brand is one of the most important assets that an organization has. It is a complex collectionof experiences and images that belongs to the surrounding world and it can have a huge impacton the organization. Today, brands are used in various ways and in different areas. One of theseareas is employer brand. In order to strengthen the employer brand, organizations can workwith employer branding, which is a long-term strategy that can be applied both internally andexternally. By working with employer branding from the internal perspective, organization canreduce their employee turnover. This is especially important for organizations today, since theunemployment in Sweden is relatively low and the labour market belongs to the workers. Thisprovides a challenge for the future success of organizations, since it is the human capital inthese organizations that possess knowledge. In Sweden, one of the characteristics of thetelecom industry is that the customer consultants have a high percent of employee turnover.The purpose of this study is therefore to investigate how organizations within the telecomindustry can reduce employee turnover with the help of internal employer branding.To gain a deeper understanding of the purpose, this study was conducted as a qualitative, singleand imbedded case study where the empirical material was collected through semi structuredinterviews. The results of the study showed that the investigated organization did not have asustainable and distinct strategy regarding internal employer branding. This was demonstratedby the fact that the leadership did not have an homogenous direction and the employees andprevious employees did not share the organizations experience regarding their work to retainemployees, therefore the efforts did not get the desired effect. This can affect the employerbrand in a negative way and therefore it is crucial that organizations understand the importanceof internal employer branding and the components that affects the employer brand. There areno shortcuts in building an employer brand and retain employees, the organization has to beattentive to what the employees truly desire.

  • Friberg, Jakob
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Investigation of Metallic Dust formed on Steel Substrates in Solar Cell Sputtering Chambers2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Investigations have been done as of why dust particles appear in a circular pattern on the backside of solar cells produced in sputtering chambers at Midsummer AB. An experimental approach was conducted, where solar cells were produced at standard conditions and their backside studied by material analytical methods. The solar cells dust particles were analyzed by energy-dispersive x-ray spectroscopy and x-ray diffraction, deducing that they consisted of iron selenide (Fe0.89Se). Furthermore, the dust particles appear due to formation of a thin iron selenide film that cracks and delaminate upon cooling from process temperature to room temperature. Iron selenide film thickness was found by energy-dispersive x-ray spectroscopy to occur in a pattern with radial symmetry with respect to the cell center, correlating with the film delamination pattern. The reason to the film formation was due to selenium reacting with the substrate steel at high temperatures (>400 C) in deposition chambers having a selenium environment. The film delamination occurs at a critical film thickness at which stresses in the film is high enough for the film to yield and fracture.

    It was concluded that iron selenide film formation or delamination must be minimized in order to control dust particle formation. These two phenomena can be mitigated by protective substrate films, change of substrate material, selenium environment optimization or temperature profile optimization and should be researched further to find the most effective and viable solution.

  • Karlsson, Tobias
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Study on the impact of CNT or graphene reinforced interlaminar region in composites2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The interlaminar region is a contributing factor to the limited electrical conductivity of carbon fiber/epoxy composites. Consisting of electrically insulating epoxy matrix between conductive layers of carbon fiber, the interlaminar region prevents electrical interaction between the carbon fiber layers and electrical conduction in the through thickness direction.The interlaminar region in thin [0,0] carbon fiber/epoxy composites has been reinforced by carbon nanotubes (CNT) by two methods. First by aligned CNT forests from N12 Technologies and secondly by self-produced Buckypapers, porous CNT films, of different areal densitites. Two batches of laminates modified by aligned CNTs, having different curing conditions, and laminates modified with Buckypapers were manufactured. The laminates were evaluated by their electrical conductivity and electromagnetic interference shielding efficiency (EMI SE). The addition of external pressure to the laminates during curing brought an increase in longitudinal conductivity, a consequence of higher fiber packing. Also, both reinforcement methods increased the longitudinal conductivity through improved electrical interaction between the carbon fiber layers. However, only the Buckypaper reinforcement augmented the transversal conductivity significantly, acting as a highly conductive route in the interlaminar region. Both batches of aligned CNT modified laminates exhibited equal EMI SE, questioning the influence of the conductivity of the laminate on its EMI SE. Also, the increase in EMI SE brought by the aligned CNT forests were negligible compared to the reference. However, the reinforcement by Buckypapers proved successful, reaching -45/-50 dB at 1000 MHz, improving from 30 dB of the unmodified reference at the same frequency.

  • Weber, Fabian
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Optical Analysis of the Hydrogen Cooling Film in High Pressure Combustion Chambers2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    For performance optimisation of modern liquid cryogenic bipropellant rocket combustion chambers, one component which plays an important role in reducing the wall side heat flux, is the behaviour of the cooling film. At the Institute of Space Propulsion of the German Aerospace Center (DLR) in Lampoldshausen, hot test runs have been performed using the experimental combustion chamber BKM, to investigate the wall side heat flux which is -- among other factors -- dependent on cooling film properties. To gain more insight into the film behaviour under real rocket-like conditions, optical diagnostics have been applied. The chosen methods were shadowgraphy and OH* imaging producing optical data sets which are analysed in this study. In this context, a description of the necessary background information is given, concerning rocket combustion chambers, film cooling and optical diagnostics of O2/H2 combustion. The applied methodology for optical analysis is described, followed by a presentation of the results. During the test campaign, it became clear that the optical setup was not optimised for creating meaningful shadowgraphy recordings which is why the shadowgraphy data has to be treated as flame emission imaging.

    The behaviour of the gas layer adjacent to the chamber wall could be characterised based on qualitative (luminosity, LOx shadow, reflection, recirculation zone and flame shape) and quantitative (layer thickness, layer length, pressure conditions) analysis. The thickness could be identified for each load step and an average length of the layer was found as well. OH* imaging has been used supplementary to support the observations from the flame emission images. An in depth frame by frame analysis was not possible due to time constraints. However, the time averaged images yielded results in accordance to the flame emission and could give a relative figure for the temperature distribution in the combustion volume. An artefact in the data was found, stemming presumably from the image intensifier. This artefact needs to be researched for a future error reduction in the data of this and other campaigns. Additionally, the thickness of the layer suggested a correlation to the models for film cooling efficiency. Such a correlation could not be established. Nevertheless, the film cooling models show the same behaviour as the data obtained from the flame emission imaging. Finally, suggestions are given how the data analysis and the optical setup could be improved for future, similar campaigns.

  • Persson, Marcus
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Software Development and Qualification Testing of a CubeSat X-ray Monitor2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The CUBES (CUbesat x-ray Background Explorer using Scintillators) is a payload on the KTH student satellite MIST (MIniature STudent satellite) to evaluate Silicon Photo-multiplier technology and new scintillators such as GAGG (Gadolinium Aluminium Gallium Garnet, Gd3Al2Ga3O12) for future use in hard X-ray polarisation studies of Gamma-Ray Bursts. CUBES itself is designed to study the MIST in-orbit radiation environment by using a detector which is comprised of a silicon photomultiplier coupled to different scintillator materials. Three of these detectors will be mounted on the payload platform and then coupled to inputs of an Application Specific Integrated Circuit (ASIC) and connected to a Field-programmable Gate Array (FPGA) which will store and send data through the downlink on the MIST satellite to ground. This thesis covers the software development for the FPGA, together with two radiation tests of components and the preparation of these.

  • Bergman, Liza-Marie
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Edman, Ida
    Luleå University of Technology, Department of Health Sciences.
    Distriktssköterskors erfarenheter av samarbete med patientansvarig läkare vid palliativ vård i hemmet2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Många gånger är det distriktssköterskor som står patienter närmast och är patienternas talesperson men det krävs ett multiprofessionellt samarbete för att kunna se till alla behov och skapa förutsättningar för patienter att uppleva livskvalitet sista tiden i livet. Då fler väljer att dö hemma är det centralt att samarbetet mellan distriktssköterskor och patientansvarig läkare fungerar för att kunna erbjuda god vård. Syftet med denna studie var att beskriva distriktssköterskors erfarenheter av samarbete med patientansvarig läkare vid palliativ vård i hemmet. Distriktssköterskor med minst ett års erfarenhet inom palliativ vård i hemsjukvården deltog i studien. Datainsamling utfördes med semistrukturerade intervjuer av åtta distriktssköterskor och data analyserades med hjälp av kvalitativ innehållsanalys. Dataanalysen resulterade i fyra subteman: Frustrerande att behöva strida för samarbete; Kontinuiteten är bristande; Tidigt engagemang från läkare ger bättre vård samt Att tillsammans ligga steget före. Det övergripande temat var Att sträva efter bättre tillgänglighet av läkare för en trygg vård. Distriktssköterskor beskrev att läkare inte prioriterade palliativ vård i samma utsträckning som dem samt att det var brist på patientansvariga läkare. Individuella samt organisatoriska faktorer ligger till grund för kvaliteten på samarbetet och därmed också möjligheten att kunna erbjuda palliativa patienter en god och säker vård.

  • Nahar, Nazmun
    et al.
    BGC Trust University Bangladesh, Bidyanagar, Chandanaish, Bangladesh.
    Ara, Ferdous
    Department of Computer Science and Engineering, BGC Trust University, Bangladesh.
    Neloy, Md. Arif Istiek
    Department of Computer Science and Engineering, BGC Trust University, Bangladesh.
    Barua, Vicky
    Department of Computer Science and Engineering, BGC Trust University, Bangladesh.
    Hossain, Mohammad Shahadat
    University of Chittagong, Bangladesh.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A Comparative Analysis of the Ensemble Method for Liver Disease Prediction2019In: Proceedings of International Conference on Innovation in Engineering and Technology (ICIET), 2019Conference paper (Refereed)
    Abstract [en]

    Early diagnosis of liver disease is very important in order to save human lives and take appropriate measure to control the disease. In several fields, especially in the field of medical science, the ensemble method was successfully applied. This research work uses different ensemble methods to investigate the early detection of liver disease. The selected dataset for this analysis is made up of attributes such as total bilirubin, direct bilirubin, age, sex, total protein, albumin, and globulin ratio. This research mainly aims at measuring and comparing the efficiency of different ensemble methods. AdaBoost, LogitBoost, BeggRep, BeggJ48 and Random Forest are the ensemble method used in this research. The study shows that LogitBoost is the most accurate model than other ensemble approaches.

  • Jaunky, Vishal Chandr
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Jeetoo, Jamiil
    Department of Economics and StatisticsUniversity of Mauritius, Reduit, Mauritius.
    Rampersad, Shreya
    Department of Economics and StatisticsUniversity of Mauritius, Reduit, Mauritius.
    Happiness and Consumption in Mauritius: An Exploratory Study of Socio-Economic Dimensions, Basic Needs, Luxuries and Personality Traits2019In: Journal of Happiness Studies, ISSN 1389-4978, E-ISSN 1573-7780Article in journal (Refereed)
    Abstract [en]

    Mainstream economics perceive an individual as highly individualistic, presuming that he/she consumes goods in the most efficient way to optimize his/her level of happiness. This study attempts to explore the nexus between socio-economic dimensions, basic needs, luxuries and personality traits and happiness in Mauritius. Material consumption and happiness are projected to be positively and strongly related. This is usually illuminated in terms of the increased possibilities to satisfy basic needs and luxuries along with other motives which additional spending provides. Other instrumental aspects of consumption, such as its relative, community-based and hedonic magnitudes are accounted. Cross-sectional data are compiled from a household survey with a sample size of 1015 observations. To conduct the analysis, an ordered probit model is applied. The general conclusion is drawn upon the results that socio-economic indicators like educational attainment, residential location, family size, income in addition to the intermediate needs deprivation index, brand consciousness, fashion innovativeness, commercial interest, shopping enjoyment, hedonism, bandwagon effect and personality traits are significantly related to people’s happiness.

  • Boström, Margareta
    Luleå University of Technology, Department of Arts, Communication and Education.
    Fritidshemmets lärmiljöer: Fritidshemmets lärmiljöer ur specialpedagogiskt perspektiv2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Abstrakt Syftet med studien var att belysa fritidshemmets lärmiljöer med focus på hur specialpedagogiskt perspektiv kommer till uttryck i mötet med den fysiska och den sociala lärmiljön. Den fysiska och den sociala lärmiljön observerades på ett fritidshem. Det relationella specialpedagogiska perspektiv var det perspektiv som framträdde tydligast i relation till den sociala och fysiska lärmiljön. Det kategoriska perspektivet kan bli en konsekvens av organisationens bemanningspolitik och elevgruppernas storlek. Det kategoriska perspektivet kan även framträda i den visuellt tillgängliga fysiska lärmiljön. Dilemmaperspektivet blir synligt när gruppen delas och gruppen befinner sig i utemiljön. En del av resultatet i den här kvalitativa studien är att tiden är en styrande ramfaktor under en dag i fritidshemmet. En annan sak som framkom var att organisationens bemanning kan vara ett hinder till att alla elever får det stöd de behöver för att kunna vara delaktiga i aktiviteterna som fritidshemmet erbjuder till att uppnå läroplanens mål.

  • Pettersson, Fredrik
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Optimizing Deep Neural Networks for Classification of Short Texts2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master's thesis investigates how a state-of-the-art (SOTA) deep neural network (NN) model can be created for a specific natural language processing (NLP) dataset, the effects of using different dimensionality reduction techniques on common pre-trained word embeddings and how well this model generalize on a secondary dataset. The research is motivated by two factors. One is that the construction of a machine learning (ML) text classification (TC) model is typically done around a specific dataset and often requires a lot of manual intervention. It's therefore hard to know exactly what procedures to implement for a specific dataset and how the result will be affected. The other reason is that, if the dimensionality of pre-trained embedding vectors can be lowered without losing accuracy, and thus saving execution time, other techniques can be used during the time saved to achieve even higher accuracy.

    A handful of deep neural network architectures are used, namely a convolutional neural network (CNN), long short-term memory neural network (LSTM) and a bidirectional LSTM (Bi-LSTM) architecture. These deep neural network architectures are combined with four different word embeddings: GoogleNews-vectors-negative300, glove.840B.300d, paragram_300_sl999 and wiki-news-300d-1M.

    Three main experiments are conducted in this thesis. In the first experiment, a top-performing TC model is created for a recent NLP competition held at Kaggle.com. Each implemented procedure is benchmarked on how the accuracy and execution time of the model is affected. In the second experiment, principal component analysis (PCA) and random projection (RP) are applied to the pre-trained word embeddings used in the top-performing model to investigate how the accuracy and execution time is affected when creating lower-dimensional embedding vectors. In the third experiment, the same model is benchmarked on a separate dataset (Sentiment140) to investigate how well it generalizes on other data and how each implemented procedure affects the accuracy compared to on the original dataset.

    The first experiment results in a bidirectional LSTM model and a combination of the three embeddings: glove, paragram and wiki-news concatenated together. The model is able to give predictions with an F1 score of 71% which is good enough to reach 9th place out of 1,401 participating teams in the competition. In the second experiment, the execution time is improved by 13%, by using PCA, while lowering the dimensionality of the embeddings by 66% and only losing half a percent of F1 accuracy. RP gave a constant accuracy of 66-67% regardless of the projected dimensions compared to over 70% when using PCA. In the third experiment, the model gained around 12% accuracy from the initial to the final benchmarks, compared to 19% on the competition dataset. The best-achieved accuracy on the Sentiment140 dataset is 86% and thus higher than the 71% achieved on the Quora dataset.

  • Paniagua, Cristina
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Eliasson, Jens
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Delsing, Jerker
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Efficient Device-to-Device Service Invocation Using Arrowhead Orchestration2019In: IEEE Internet of Things Journal, ISSN 2327-4662Article in journal (Refereed)
    Abstract [en]

    The Internet of Things (IoT) enables interaction from real-world physical objects using sensors to the virtual world of computers and the Internet. The use of service-oriented architecture (SOA) is one step in the creation of basic and complex interactions between several sensors and actuators. However, the use of SOA-enabled technologies alone does not meet all requirements of how sensor and actuator systems could be integrated to create distributed monitoring and control applications. The centralized, traditional method of communication in wireless sensor networks via a gateway presents drawbacks that have to be addressed; device-to-cloud communication adds higher latency and higher power consumption and is less robust than the device-to-device communication approach. Moreover, all these characteristics reduce the scalability of the network, thus limiting the use of IoT in the industry. In this paper, the proposed method utilizes the Arrowhead framework orchestration system to generate service composition within a (wireless) network formed by IoT devices. The aim is to achieve efficient device-to-device service invocation to reduce the drawbacks of today's widely used device-to-cloud approach. The method in this paper performs efficient service composition for industrial IoT, including mapping SOA service composition in very small resource-constrained devices using the Arrowhead orchestration. The results presented in this paper at the service level can increase performance and robustness in fog computing on resource-constrained devices.

  • Westberg, Erik (Conductor)
    Luleå University of Technology, Department of Arts, Communication and Education, Music, media and Theatre.
    The Cloud of Unknowing2019Artistic output (Unrefereed)
  • Westberg, Erik (Conductor)
    Luleå University of Technology, Department of Arts, Communication and Education, Music, media and Theatre.
    POESIS: Bohuslän Big Band under ledning av Örjan Fahlström. Varbergs kammarkör samt sångare ur Erik Westbergs Vokalensemble under ledning av ErikWestberg.2019Artistic output (Unrefereed)
  • Soleimanmeigouni, Iman
    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.
    Khajehei, Hamid
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Nissen, Arne
    Trafikverket, Luleå, Sverige.
    Investigation of the effect of the inspection intervals on the track geometry condition2019In: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980Article in journal (Refereed)
    Abstract [en]

    In order to evaluate the railway track geometry condition and plan maintenance activities, track inspection cars run over the track at specific times to monitor it and record geometry measurements. Applying an adequate inspection interval is vital to ensure the availability, safety and quality of the railway track, at the lowest possible cost. The aim of this study has been to investigate the effect of different inspection intervals on the track geometry condition. To achieve this, an integrated statistical model was developed to predict the track geometry condition given different inspection intervals. In order to model the evolution of the track geometry condition, a piecewise exponential model was used which considers break points at the maintenance times. Ordinal logistic regression was applied to model the probability of the occurrence of severe isolated defects. The Monte Carlo technique was used to simulate the track geometry behaviour given different inspection intervals. The results of the proposed model support the decision-making process regarding the selection of the most adequate inspection interval. The applicability of the model was tested in a case study on the Main Western Line in Sweden.

  • Wikström, Catarina
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Lennestål, Ewa
    Luleå University of Technology, Department of Health Sciences.
    Sjuksköterskors upplevelser av svårigheter vid palliativ vård i hemmet2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: Hemsjukvården ökar och allt fler palliativa patienter vårdas i hemmen. Det ställer stora krav och planering av sjuksköterskan i hemsjukvården för att få allt att fungera i det palliativa skedet då patienten är extra utsatt. Syftet är att beskriva sjuksköterskors upplevelser av svårigheter vid palliativ vård i hemmet. Metod: En kvalitativ studie med semistrukturerade intervjuer med åtta sjuksköterskor. Data analyserades med en kvalitativ innehållsanalys som resulterade i fyra kategorier och ett tema. Resultat: Kategorierna var; Främja trygga relationer för alla, vilket sjuksköterskorna betonade som en svårighet, och som fick stor betydelse för omvårdnaden och acceptans av situationen. Samverkan och kommunikation, skapade svårigheter att ge en god omvårdnad. Hänsyn till behov och önskemål, upplevde sjuksköterskorna var svårt när mångas behov ställdes mot varandra. Med Hemmet som arbetsplats, ansåg sjuksköterskorna att det var svårt att ge en säker och hänsynsfull omvårdnad. Den övergripande tematiseringen resulterade i begreppet; ”Att balansera på slak lina”. Slutsats: Sjuksköterskor i palliativ hemsjukvård upplever många svårigheter i sitt dagliga arbete. Resultatet av denna studie visar att det finns stor osäkerhet i hur den enskilda sjuksköterskan ska hantera detta.

  • Winnberg, Anton
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Waterproof packing for urban outdoor: Development of two waterproof backpacks intended for daily bike commute, urban strolls and travel2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Everyday, lots of people use some sort of bag to carry their daily equipment around, whether it is between home and work or any typ of spare time activity. This report covers a Master Thesis project in Industrial Design Engineering at Luleå University of Technology. The thesis concerns the development of two waterproof backpacks. These backpacks are developed in collaboration with the outdoor brand Lundhags, and intended for everyday bike commute, urban excursion and travel. Behind the initiative lies the desire of expanding the company’s product portfolio with a set of new waterproof daypacks within the category of urban outdoor. Also, to offer the customers the better protection of electronic devices such as laptops, surf tablets and smartphones, which are products that are prominent in our daily lives. 

    The project has followed a schedule and workflow influenced by versions of the design thinking process, with multiple iterations along the way. The work started off by studying competing products on the market, research and conduct knowledge on relevant topics through a literature review, study users needs and gather inspiration. User studies where carried out as interviews with both users and retailers, where the result was summarised as personas to represent the target audience. The contextual studies laid the foundation for the rest of the project, which further shifted towards more practical activities. Such as ideation sketching, building textile and paper mock-ups, concept development and concept evaluation. The result of this thesis project was the first version technical drawings for two backpack concepts. During the final weeks, these drawings were sent to the manufacturer for production of first version prototypes and production cost proposal. The bags are planned as a 16 liter and a 22 liter, where they offer internal options of organising the packing, as well external access pockets for smaller items to be close at hand.

  • Biswas, Munmun
    et al.
    Department of Computer Science and Engineering, BGC Trust University Bangladesh, Bidyanagar, Chandanaish, Bangladesh.
    Chowdury, Mohammad Salah Uddin
    BGC Trust University Bangladesh, Chandanaish, Chittagong-4381, Bangladesh.
    Nahar, Nazmun
    University of Chittagong, Bangladesh.
    Hossain, Mohammad Shahadat
    University of Chittagong, Bangladesh.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A Belief Rule Base Expert System for staging Non-Small Cell Lung Cancer under Uncertainty2019In: Proceedings of 2019 IEEE International Conference on Biomedical Engineering, Computer and Information Technology for Health (BECITHCON), 2019Conference paper (Refereed)
    Abstract [en]

    Non small cell Lung cancer (NSCLC) is one of the most well-known types of Lung cancer which is reason for cancer related demise in Bangladesh. The early detection stage of NSCLC is required for improving the survival rate by taking proper decision for surgery and radiotherapy. The most common factors for staging NSCLC are age, tumor size, lymph node distance, Metastasis and Co morbidity. Moreover, physicians’ diagnosis is unable to give more reliable outcome due to some uncertainty such as ignorance, incompleteness, vagueness, randomness, imprecision. Belief Rule Base Expert System (BRBES) is fit to deal with above mentioned uncertainty by applying both Belief Rule base and Evidential Reasoning approach .Therefore, this paper represents the architecture, development and interface for staging NSCLC by incorporating belief rule base as well as evidential reasoning with the capability of handling uncertainty. At last, a comparative analysis is added which indicate that the outcomes of proposed expert system is more reliable and efficient than the outcomes generated from traditional human expert as well as Support Vector Machine (SVM) or Fuzzy Rule Base Expert System (FRBES).

  • Holmbom, Lina
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Jonsson, Sofia
    Luleå University of Technology, Department of Health Sciences.
    Fysisk aktivitet och välbefinnande hos elever i årskurs nio – En kvantitativ tvärsnittsstudie2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: Fysisk inaktivitet är ett globalt hälsoproblem och världshälsoorganisationen, WHO, har beräknat att 81% av världens barn och ungdomar i åldern 5–17 år inte är tillräckligt fysisk aktiva. Specifikt gällande barn och ungdomar har fysisk aktivitet många positiva effekter. Dessa kan ses både på lång och kort sikt. Fysisk aktivitet har visat sig bidra till psykisk hälsa och en bättre upplevd livskvalitet. Syfte: Syftet med denna studie var att undersöka sambandet mellan fysisk aktivitet och välbefinnande hos elever i årskurs nio. Design och metod: Studien utfördes genom en kvantitativ tvärsnittsstudie i form av pappersenkäter. Resultatet från enkäterna analyserades med kvantitativ metod. Resultat: Enkätstudien visar att pojkar har skattat ett högre välbefinnande änflickor och annan. Det gick inte att se ett signifikant samband mellan vardagsmotion och skattat välbefinnande. Gällande den fysiska träningen och det skattade välbefinnandet kunde ett statistiskt samband påvisas. Även vid sammanslagning av den skattade fysiska träningen samt vardagsmotionen kunde ett signifikant samband ses. Slutsats: Det är viktigt att uppmuntra elever till fysisk aktivitet samt att arbeta för att stärka deras self-efficacy, självförmåga för ett ökat välbefinnande.

  • Andersson, Josefine
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hur kan en befintlig centrumnära galleria omformas för att bidra till en mer attraktiv och hållbar stad?: En studie av Odenhuset i Trollhättan2019Independent thesis Advanced level (professional degree), 300 HE creditsStudent thesis
    Abstract [en]

    During 1960 and 1970, several Domus department stores opened in the city centres of Sweden. By car, both local and long distance visitors could visit the Domus department store. As the external shopping centres and electronic commerce appeared, the number of visitors to the city malls (previously Domus department stores) has decreased. Nowadays, it is common for trade business to be forced to close the business because of the competition from external shopping centres and electronic commerce. This results in the fact that empty rooms nowadays are commonly found in city mall buildings. With the empty spaces, the city mall buildings have a limited range of goods and services. Less visitors to the city mall buildings result in less visitors to the place next to the city mall building, but also less visitors to the entire city centre.The purpose of this master thesis is to contribute with increased knowledge of how the existing city mall buildings can be redesigned as an idea and in its design. This because it is necessary to meet today’s challenges how the city mall buildings can contribute to a better sustainable and an attractive urban environment. The aim of this master thesis is to find a new design and function for Odenhuset in Trollhättan. The result should also be able to apply for similar existing city malls in central urban environments.The study was conducted by using the method called Research by Design. The method contains the three phases: pre-studies, design process and design analysis. Through Research by Design, it is possible to create a design proposal for the new function of the building where the proposal is based on scientific pre-studies. The first phase pre-studies includes site visits and literature studies. The city mall buildings that were visited for thestudy are either in the leading edge of Mixed Use or does the visited city mall building has many empty premises in the building.The conclusion of this master thesis is to find a new function for a centreclose city mall building, it is essential to accept the trade development. How trade has developed and changed is based on what human needs has looked like. Since external shopping malls and electronic commerce meetpeople nowadays needs better than the city malls does, the competition for customers has arisen. The result of the design proposal is therefore flexible and adaptable in order to make the city mall buildings once againbe able to meet new and future human needs. The design proposal and the new function of the city mall building should conveniently include different activities available for everyone. To combine different activities creates a wider range for the place. A wider range makes better conditions for the building to get more visitors and movement around the place.The design proposal gives space in the city mall building for activities thatmakes people’s everyday lives work better.

  • Arapantonis, Elpidoforos
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Data tampering in Vehicle CAN Bus networks2019Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    The paradigm of the automotive industry has changed, over the course of the last10-15 years. Electronics and software, have introduced in many dierents parts ofa vehicle and the drive-by-wire it is taking over the vehicle functions. Connectivityfunctionalities are increasing in the context of the automotive industry as well. Allthe aforementioned parts have more than one common link. This thesis project willfocus on one of these links, which is the security. The focus will be the CAN busprotocol and specically, on investigating the implications of an adversary havingphysical access in a vehicle. An experiment will be contucted as part of this thesiswork, by using open source hardware (Arduino and Raspberry Pi) and a Man-inthe-middle (MITM) attack scenario, will be implemented. The application, whichwill perform the MITM attack (small scale CAN bus fuzzer) will be developedduring this project and it will be distributed as an open source software afterwards.