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  • Forslund, Max
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Ek, Johannes
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Digitalt projektledningsverktyg baserat på principer inom gamification: Med syftet att öka motivationen och engagemanget i användandet2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I denna studie har ett konstruktionsarbete utförts där ett projektledningsverktyg tagits fram. Projektledningsverktyget ämnar till att öka de värdeskapande processer som sker i användandet av verktyget. Syftet med studien är därmed att undersöka hur motivationen och engagemanget i användandet kan höjas genom att implementera gamification-principer i verktygets gränssnitt och funktionalitet. Studien bygger på en förstudie från tidigare forskning inom projektledning och planering samt tjänsteinnovation som blir den bakomliggande strukturen i studien. Detta kombineras med teorier och principer inom interaktionsdesign, UX/UI-design och gamification, vilket själva konstruktionsarbetet grundar sig på. Under arbetet med studien har Action Design Research tillämpats som övergripande forskningsmetod men har även kombinerats med Arvolas designprocess för att ge ytterligare stöd till konstruktionsarbetet av verktyget. Genom denna process har arbetet utförts i ett nära samarbete med digitalbyrån Samuraj, där idén om ett nytt projektledningsverktyg vuxit fram. Företaget har även varit ett stort stöd genom processen där flera möten och dialoger har ägt rum för att samla in värdefull information och utvärdera koncept kring projektledningsverktyget. Studien ämnar därmed till att presentera ett designförslag som genomgått flera iterationer vilket i sin tur resulterat i en interaktivprototyp.

  • Ganström Niemi, Karin
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Norberg, Therese
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Upplevelser av att vårda en anhörig med demens: En litteraturstudie2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: Idag lever cirka 130000 - 150000 människor med en demensdiagnos. På grund av brist på resurser vad gäller vårdplatser och personal så sker mycket av den långsiktiga vården i hemmet och vårdbördan för familjen ökar. För att kunna ge stöd och stärka anhörigvårdare i deras hälsa finns ett behov av att veta vilka upplevelser de har. Syfte: Syftet med litteraturstudien var att beskriva upplevelser av att vårda en anhörig med demens. Metod: En kvalitativ litteraturstudie med ett inifrån perspektiv. Sökning genomfördes i två olika databaser och tio artiklar som svarade mot syftet valdes ut. Dessa kvalitetsgranskades. En kvalitativ manifest induktiv innehållsanalys genomfördes. Resultat: Efter dataanalysen framträdde fem kategorier: Att livssituationen förändras, Att pendla mellan oro och förtvivlan, Att egen tid och stöd behövs för att orka, Att ha behov av kunskap och information, Att hitta nya sätt att leva tillsammans. Slutsats: Livet blir påverkat och det sker en transition. Genom utbildning kan hanterbarheten öka. Det är viktigt att sjukvården ger stöd för att underlätta situationen

  • Valdrina, Kastrati
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Wiveson, Caroline
    Luleå University of Technology, Department of Health Sciences.
    Fördelar och nackdelar med att använda Cone Beam CT som ett diagnostiskt verktyg för frakturer i distala extremiteter2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Cone Beam Computed Tomography (CBCT) is a relatively new modality to be used in orthopedic for various types of injuries and the usage is increasing. The authors of this study have only encountered this modality a little bit during school, which meant that their interest in learning more about it was big. The purpose of this study was to compile the advantages and disadvantages of this modality in fracture examination in extremities. The method used for this study was a general literature study, where facts were collected from articles in different databases and also in literature. The quality review was done by both authors according to a quality audit protocol that was tailor-made to suit the study well.  In the analysis, the information was compiled from the articles and categorized to make the result more easy to understand. The result showed that more fractures were found using CBCT than conventional X-ray. This was especially true of scaphoidum, carpal, and wrist fractures. It also proved to be an aid in assessing unstable or stable ankle after a certain type of ankle fracture. Magnetic resonance (MR) proved slightly better than the CBCT to detect scaphoid fractures. The fracture detection capability of the CBCT was similar to that of Multi Detector Computed Tompography (MDCT). The radiation dose from the CBCT was found to be higher than in conventional X-rays, but less than the radiation dose from the MDCT. The CBCT was also cheaper to buy and maintain than the MDCT. The CBCT proved to have a common type of artifacts, such as beam-hardening artifacts and movement artifacts. The authors of this study believe that the CBCT may be a good complement to conventional x-ray in various fractures in extremities, but more research needs to be done as this area is still relatively new and the information is limited.

  • Hakola, Anna
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Sjaunja, Anna
    Luleå University of Technology, Department of Health Sciences.
    Att minska ångest hos barn i samband med en MUCG-undersökning: En litteraturöversikt2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Introduction: Voiding cystourethrogram (VCUG) is an x-ray examination that is used to diagnose vesicoureteral reflux in children. The examination is both physically and mentally stressful and for children it can be experienced as an anguished examination. Parents have an important role in the examination and the radiographer needs to know how children's anxiety can be eased in order to help parents support their children. Children’s anxiety can be demonstrated in several ways during the examination, which may complicate the diagnosis. Purpose: The aim of this literature review was to highlight factors that may reduce anxiety in children before and during a VCUG examination. Method: The study was performed as a literature review. A systematic literature search in the databases PubMed and CINAHL was performed. Twelve scientific articles which replied to the aim of this study were collected for quality review, then those articles were analyzed and the result were divided into categories. Results: From the data analysis three categories were identified to describe factors that can reduce children’s anxiety; information and preparation, adult influence on the child and alternative methods. Conclusion: Information and preparation as well as the influence of parents have great importance to children’s anxiety. Through increased understanding, the radiographer can support both the children and parents during the examination and also contribute to the design of new routines.

  • Öberg, Maria
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Motivationsfaktorer bakom oreglerat arbete inom hästbranschen2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Ridsport är en hobby som engagerar tusentals personer. För några av dessa personer är det en dröm att få göra denna hobby till sitt yrke. Till branschens baksidor hör dock låga löner, långa arbetsdagar och svartarbete. Som en följd av detta påverkas både pension, sjuk-och semesterersättning. I många fall finns inga försäkringar som täcker uppkomna skador och olyckor i arbetet. Trots detta väljer en stor skara människor att arbeta med hästar. Studiens syfte är att ta reda på vilka motivationsfaktorerna inom hästbranschen är, trots ovanstående problem. Fem kvinnliga hästskötare har intervjuats i studien. Samtliga respondenter har arbetat i tävlings-och träningsstall med inriktning hoppning. Resultatet har analyserats med hjälp av Herzbergs tvåfaktorteori och Oldham och Hackmans arbetsdesignteori. Resultatet visar att det finns ett gemensamt mönster av motivationsfaktorer för samtliga respondenter. Dessa motivationsfaktorer är intresse, sociala relationer, utvecklingsmöjligheter och arbetets överensstämmelse med medarbetaren.

  • Hassabelnaby, Aly
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Development of a maintenance plan for the STEPWISE project at Swerea MEFOS2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Process plants come with a wide variety of engineering challenges. Each process has uniqueoperating conditions that require careful operation and maintenance programs to keep the process equipment in a condition that is safe for operation. A pilot-scale plant was built in Luleå to demonstrate the possibility of carbon dioxide removal from blast furnace gas usingthe Sorption Enhanced Water Gas Shift (SEWGS) technology. One of the challenges facingthe SEWGS pilot plant was the lack of a maintenance plan which was the motivation for this thesis.

    The aim of this thesis was to create a maintenance plan for the SEWGS pilot plant. Studying the process conditions of the pilot plant was the starting point since an understanding of the unique operating conditions was necessary for creating a maintenance plan for the pilot plant’s equipment.

    The Reliability-centered maintenance (RCM) method was chosen to create the maintenance plan. The study began with determining the objectives and contents of the analysis. The next step was a functional failure analysis in the form of a Failure Mode and Effect Criticality Analysis (FMECA) covering all the equipment in the plant. Afterwards the failure consequences were assessed based on a criticality assessment matrix to determine which equipment necessitate the performance of maintenance activities.

    The maintenance plan was created based upon the criticality of the equipment and the selected maintenance activities were based on the recommendations of manufacturers. The failure analysis found that the blast furnace gas compressor is the most critical for the process. The boiler and superheater have been found to be highly critical due to the dangerous safety consequences of their failure.

    In addition, all pressure safety valves have been found to be highly critical due to the hidden nature of their failure. The maintenance plan addresses these critical items and other less critical items while some non-critical items have been removed from the plan due to the negligible consequences of their failure.

  • Wahlstedt, Fredrik
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Nilsson, Johannes
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Tillämpning av drönare för tillståndsbedömning av järnvägsterräng2018Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    In railway maintenance, condition assessment is an important part of getting more effective preventive maintenance, as well as meeting safety and accessibility requirements. The management of railway infrastructure is a part of the Swedish Transport Administration’s core in railway operations. New and innovative technology is a way to improve management efficiency, a way to do this is with the help of drones. Drones is a new technology application that supports digitized facility monitoring. By using drones during inspections, railway traffic run as usual while inspections are carried out quickly and smoothly. In railway maintenance, condition assessment is an important part of being able to get a more effective preventive maintenance, as well as meet the requirements for safety and accessibility. The purpose of the work is to create an initial survey which shows what possibilities there are today for applying drones when inspecting railway and railway infrastructure, as well as provide a basis for drone applications inside the Swedish Transport Administration’s operations within condition assessment of railway terrain. The aim is to create a plan for how the Swedish Transport Administration’s operation can use drones to support railway terrain assessment. A part of a FMECA has been used to see what opportunities there are when using drones on railway. A SWOT-analysis have been carried out explaining the strengths, weaknesses, opportunities and risks/threats that exist when drones are applied for inspection of railway terrain.

    Drones have a big limitation because, according to rules, they must be aired within the sight of the pilot. If the Swedish Transport Administration gets permission to fly drones out of eyesight, the possibilities of inspecting longer distances could occur. If drones are implemented in the Swedish Transport Administration’s operations, it may support the current methods for railway terrain condition assessment. Through analysis of interviews, literature studies and a field study, the results have been that drones can be applied to carry out condition assessment of railway terrain and that there are possibilities to do inspections of railway and railway infrastructure. Implementation of drones would allow for the streamlining of railway terrain condition assessment. It can also streamline administration and support traditional monitoring methods, it will also be able to support the fulfillment of delivery qualities and constitutional compliance.

  • Flaten Härnvall, Elin
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Pettersson, Evelina
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Sjuksköterskors upplevelse av arbetsmiljön i hemsjukvården: En litteraturstudie2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Att vårda patienter i hemmet kan innebära utmaningar då det är svårare att anpassa arbetsmiljön. Detta har stor betydelse för hälso- och sjukvården då arbetsmiljön påverkar både sjuksköterskors hälsa, omvårdnadsarbetet, patienters upplevelse av vården och patientsäkerheten. Syftet med denna litteraturstudie var att beskriva sjuksköterskors upplevelse av arbetsmiljön i hemsjukvården. Litteraturstudien inleddes med en systematisk litteratursökning i databaser som, efter kvalitetsgranskning, resulterade i nio vetenskapliga artiklar som gick vidare till analysen. Artiklarna analyserades med en kvalitativ manifest innehållsanalys med induktiv ansats. Analysen resulterade i fyra kategorier: Att ledarskap och organisation har stor betydelse, Att utsättas för risker och faror, Att prioritera patientens behov framför den egna hälsan, Att arbeta i en miljö som inte är optimal. Resultatet visade att sjuksköterskor upplevde brist på stöd, oro för den egna hälsan samt att arbetsmiljön i hemsjukvården var både riskfylld och ej optimal att bedriva vård i. Slutsatsen är att sjuksköterskor behöver mer stöd från sina arbetsgivare samt mer tid och resurser. Arbetsmiljön hindrar även sjuksköterskor i hemsjukvården från att arbeta effektivt.

  • Hultdin, Ida
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Nilsson, Erika
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Närståendes upplevelser när en anhörig suiciderar och tiden därefter: En analys av narrativ2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Varje år suiciderar 800 000personer världen över. I Sverige 2016 avled 1 129 personer till följd av suicid. Efter ett suicid är det ett stort antal närstående som lämnas kvar. Ett suicid kan av närstående upplevas traumatiskt och leda till en stor sorg och ett enormt lidande. Syftet med denna litteraturstudie var att beskriva närståendes upplevelser av att en anhörig suicideraroch tiden därefter. Studiens resultat bygger på en kvalitativ innehållsanalys med manifest ansats där narrativ i en bok har analyserats. Detta resulterade i tre kategorier: Att nås av beskedet och söka förklaringar; Att klandra sig själv och känna skuld; Att det är viktigt att få dela sin sorg med andra och få stöd. Närstående har ett behov av stöd och tröst, både professionellt samt från vänner och familj. Sjuksköterskan kan hjälpa dessa personer genom att lyssna och identifiera deras styrkor och behov, på så vis kan närstående erbjudas rätt hjälp och stöd.

  • Nordlander, Sara
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Nilsson, Rebecca
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Kvinnors upplevelse av att leva med endometriosrelaterad smärta: En litteraturstudie2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Många kvinnor lever idag med sjukdomen endometrios. Detta är en sjukdom som präglas av ständig smärta och påverkar den drabbades liv och person. Syftet med denna litteraturstudie var att beskriva kvinnors upplevelse av att leva med endometriosrelaterad smärta. Manifest kvalitativ innehållsanalys utfördes på nio vetenskapliga artiklar vilket resulterade i fyra kategorier: Att smärtan bidrar till begränsningar i dagligt liv, att samlivet med partnern blir lidande, att vara expert på att hantera sin egen smärta och att inte ta smärtan på allvar. Det framkom att endometriosrelaterad var outhärdlig och hade en negativ inverkan på livet. Många kände sig styrda av smärtan och behövde planera sitt liv efter den. Smärtan togs inte på allvar av hälso- och sjukvården och avvisades trots långvariga besvär och hanteringen av smärtan bestod till största delen av egenvård. Det finns bristande kunskap inom området av endometrios och relaterad smärta. Detta anser vi bidrar till att många som lever med smärtan inte tas på allvar. Mer forskning behövs därför för att kunna skapa en god och trygg vård med adekvat smärtbehandling för de som är drabbade av endometriosrelaterad smärta.

  • Nordström, Josefine
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Isaksson Svensson, Lisen
    Luleå University of Technology, Department of Health Sciences.
    Patienters upplevelser av palliativ vård: En litteraturstudie2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Palliativ vård är ofta vård i livets slutskede och är inte en kurativ metod utan syftar till att ge livskvalité i livets slutskede. Detta genom att tidigt identifiera och bedöma omvårdnadsbehov samt smärt- och symtombehandling. Hälso- och sjukvårdspersonal ska bevara patientens integritet och respekt genom god omvårdnad, vilket gör att människovärdet bibehålls vid den palliativa vården. Syftet med denna litteraturstudie var att beskriva patienters upplevelser av palliativ vård. Litteratursökningen skedde i två databaser. Därefter valdes studier ut för kvalitetsgranskning vilket resulterade i tolv stycken vetenskapliga studier som sedan skulle ingå i litteraturstudien. Analysen skedde med metod enligt Graneheim och Lundman (2004) för kvalitativ innehållsanalys med en induktiv ansats. Analysen resulterade i tre kategorier: Vikten av att bli sedd och hörd för att få individuella behov tillgodosedda, Att bibehålla sin värdighet i samband med en förändrad livssituation och Att förbereda sig inför döden utan att tappa hoppet. Slutsatsen var att patienter upplevde ett behov av att bli sedd och hörd och att få alla sina individuella omvårdnadsbehov tillgodosedda. Vidare forskning i ämnet palliativ vård kan vara att öka kunskapen kring hur man talar om döden som en naturlig del av livscykeln. Detta för att skapa en trygghet för patienten. 

  • Vidgren, David
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Svensson, Nadja
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Patienters upplevelser av vårdpersonalens bemötande på akutmottagning: En litteraturstudie2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Akutsjukvården är ofta den första kontakten en patient har vid ett vårdtillfälle och i många fall även den enda kontakten en patient har med sjukvården. Vid ett besök på en akutmottagning kan en patient träffa ett antal olika vårdare av olika yrkeskategorier, vilket resulterar i många möten med många tillfällen till att få ett bra och/eller dåligt bemötande.Syftet med litteraturstudien var att beskriva patienters upplevelse av vårdpersonalens bemötande på akutmottagning. Datainsamlingen skedde genom sökning i tre databaser för att finna material. 15 artiklar kvalitetsgranskades, alla höll medel till hög kvalité. Där efter analyserades de med kvalitativ innehållsanalys. Analysen resulterade i fyra kategorier; “Förväntan att vara i handlingens centrum”, “Att bli lyssnad till av närvarande vårdpersonal”, “Att inte få information och att uppleva ett vacuum” och “Att vara ett objekt i vårdpersonalen ögon och att vara till besvär”. Många patienter upplevde att bemötandet på akutmottagningen var dåligt på grund av brist på information, medan ett gott bemötande upplevdes när vårdpersonal var närvarande och gav patienter möjlighet att berätta sin historia.

  • Dundar, Ismail Ugur
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Improvement of a Space Surveillance Tracking Analysis Tool2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Since the beginning of space exploration, the amount of space debris has increased with thedevelopment of new space technologies. In fact, when a collision happens, new space debris aregenerated. Hence, collision risk between space debris and operational satellites rises. The purpose ofa surveillance network system consists of the detection of space objects, their classification and theirtracking. To avoid collisions, space debris objects’ orbit must be computed with sufficient accuracy.

    The goal of this thesis is the improvement of a pre-existing Space Surveillance and Tracking AnalysisTool. The tool is able to simulate different observation scenarios for radar or optical observer,which can be space-based or ground-based. To enhance the orbit determination, an ExtendedSquare Root Information Filter is implemented and incremented with a Smoother. Smoothers havebeen implemented for the existing filters as well, such as the Extended Kalman Filter and theUnscented Kalman Filter. A bias estimation method was added as part of the OD for all filter types.Additionally, different outlier detection methods were implemented for the automatic detection ofoutliers within the measurement data. To find the optimum orbit determination interval, differentscenarios were considered in LEO, MEO and GEO orbits. The methods were implemented anddifferent scenarios for validation will be discussed. A wide discussion on the methods implementationand their validation on different scenarios is presented, together with a comparison of the orbitdetermination results with the other filters.

    All the recently implemented features increase the efficiency of the tool to simulate the differentscenarios and enhance the tracking of space debris objects.

  • Enlund, Anders
    Luleå University of Technology, Department of Arts, Communication and Education, Media, audio technology and theater.
    How do bass enhancement algorithms impact mixing decisions when monitoring on headphones?2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As music production moves from the big professional studios into small bedroom studios, Headphones become more commonly used for monitoring. This brings a new set of problems based on the limitations of headphones compared to loudspeakers. This research explores how a bass enhancement algorithm impacts the results when mixing low frequency audio on headphones. This is done through a simple mixing experiment where subjects are tasked with balancing the amplitude of a low frequency element in a song, both with and without a bass enhancement algorithm enhancing the headphone monitoring. It is shown that while subjects do not perceive a difference in difficulty with this task, the results differ as subjects overall mix the bass frequencies lower in amplitude when aided by the bass enhancement algorithm. It is concluded that the bass enhancement algorithm is useful in this manner.

  • Haverkamp, Kalli
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    An Analysis of the New Threat Environment for Satellites2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • Hou, Muzhou
    et al.
    School of Mathematics and Statistics, Central South University, Changsha, Hunan, China.
    Zhang, Tianle
    School of Mathematics and Statistics, Central South University, Changsha, Hunan, China.
    Weng, Futian
    School of Mathematics and Statistics, Central South University, Changsha, Hunan, China.
    Ali, Mumtaz
    School of Agricultural, Computational and Environmental Sciences Institute of Agriculture and Environment, University of Southern Queensland, Springfield, Australia.
    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.
    Global Solar Radiation Prediction Using HybridOnline Sequential Extreme Learning Machine Model2018In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 11, no 12, article id 3415Article in journal (Refereed)
    Abstract [en]

    Accurate global solar radiation prediction is highly essential for related research on renewable energy sources. The cost implication and measurement expertise of global solar radiation

    emphasize that intelligence prediction models need to be applied. On the basis of long-term measured daily solar radiation data, this study uses a novel regularized online sequential extreme learning machine, integrated with variable forgetting factor (FOS-ELM), to predict global solar radiation at Bur Dedougou, in the Burkina Faso region. Bayesian Information Criterion (BIC) is applied to build the seven input combinations based on speed (Wspeed), maximum and minimum temperature (Tmax and Tmin), maximum and minimum humidity (Hmax and Hmin), evaporation (Eo) and vapor pressure deficiency (VPD). For the difference input parameters magnitudes, seven models were developed and evaluated for the optimal input combination. Various statistical indicators were computed for the prediction accuracy examination. The experimental results of the applied FOS-ELM model demonstrated a reliable prediction accuracy against the classical extreme learning machine (ELM) model for daily global solar radiation simulation. In fact, compared to classical ELM, the FOS-ELM model reported an enhancement in the root mean square error (RMSE) and mean absolute error(MAE) by (68.8–79.8%). In summary, the results clearly confirm the effectiveness of the FOS-ELM model, owing to the fixed internal tuning parameters.

  • Lidström, Emelie
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Facket och kommunaliseringen: En fallstudie kring debatten inom Statens Sjukhuspersonalsförbund rörande kommunaliseringen av mentalvården 19672018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The study is based on a qualitative text analysis of source material. The purpose of this paper has been to investigate how a local trade union department discusses the change of mental health care from state to municipal headquarters and with the interchange of connection to a larger union. The study shows that the union activities “Statens Sjukshuspersonals Förbund” did not have a positive impression that the county council would take over mental health care, nor did it have a positive picture of the transition to the Swedish Municipal Workers' Union. Something that is based on worrying about impaired profession. The conclusion of this survey is that communalization will end “Statens Sjukhuspersonals Förbund” Association, but by that means, it does not automatically mean that it is getting worse for those employed by the county council, but it must retain the same working conditions as in state employment.

  • Nilsson, Magnus
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Ändskärmsbro: mer bro för pengarna2018Independent thesis Advanced level (degree of Master (Two Years)), 300 HE creditsStudent thesis
    Abstract [en]

    The Swedish Transport Administration (Trafikverket) takes care of some 20600 bridges. For maintenance 900 million SEK is used per year. However, this amount of money is not enough to keep all bridges in a good condition and the demand will increase as many bridges built in the 50ies and 60ies will be in need of increased maintenance.

    2 830 bridges (13%) have some form of expansion joints. These joints need frequent maintenance and they also have to be replaced after a few decades. A possibility to avoid the high costs for this would be to use bridges with end-frames instead of expansion joints. The aim of this study is to estimate how much money that can be saved by using end-frames instead of expansion joints

    Life-Cycle Cost Analyses (LCCA) have been performed. Four different bridge types have been studied each with a length of 100 m long and with varying widths (8, 14, 18,5 and 21,5 m) and Annual Day Traffic, ADT (2, 8, 16, and 40 thousand vehicles per day). The life length is set to be 120 years and the construction cost is assumed to be equal for the two alternatives expansion joints and end-frames. The interest has been set to 3,5 % and the base year is 2014. It was assumed that the number of working days to carry out an exchange of an expansion joint was 40 days and that a repair could be carried out in 1 day. Estimations of costs for accidents, delay of traffic, vehicles, environment and maintenance are made with algorithms proposed by the Swedish Transport Administration.

    The Life-Cycle Cost Calculations indicate that there is a great potential for savings. For a bridge with a width of 8 m and an Annual Daily Traffic, ADT, of 2 000, the saving for a 120-year life length is 0,5 MSEK. For a bridge with a width of 21,5 m and an ADT of 40 000, the saving will be 5 MSEK. In cities with dense traffic, disturbances quickly cause long ques and consequently high delay costs, so the savings are proportionally greater for high than for low ADTs.

    The assumptions made are discussed and possible further studies are identified (e.g. influence of interest rate, of other relationships between costs and amount of traffic and of the present rules for designing bridges with end frames).

  • Arngren, Elin
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Holma, Mia
    Luleå University of Technology, Department of Health Sciences.
    Datortomografi vid diagnostisering av ockulta höftfrakturer som inte syns på konventionell röntgen: En litteraturöversikt2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: A hip fracture is occult when it is not visible on plain x-rays. About five percent of all cervical hip fractures are occult. To diagnose the occult hip fracture, the patient must undergo further examination with another modality. Computed tomography can be such a potential examination since it gives a clear picture of the patient’s anatomy. Delay to surgery increases the risk of mortality while the patient is hospitalized, and it is therefore important that the patient get the diagnosis as quickly as possible. Purpose: To create an overview of the knowledge situation regarding computed tomography in the diagnosis of occult hip fractures not detected by plain x-rays. Method: The study was conducted as a general literature review. Ten scientific articles of quantitative method were included. Results: Computed tomography did not detect all occult hip fractures and in many cases patients had to undergo further examination. The common meantime of the sensitivity based on four of the scientific articles was 83.3 % and the common specificity was 99.15 %. Of the remaining six articles computed tomography missed a total of 15 occult hip fractures in 595 patients. The meantime after the first examination with plain x-ray until the patient received a computed tomography differed between the patients and studies. The fastest meantime was 3 hours and 42 minutes. Conclusion: Computed tomography does not detect all occult hip fractures, and in many cases patients need to undergo further examination for the correct diagnosis.

  • Wiippa, Beatrice
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Azarnia, Sadaf
    Luleå University of Technology, Department of Health Sciences.
    Förebygger kirurgiska munskydd infektion hos patienten vid interventionell radiologi?: en litteraturöversikt2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Introduction: One of the radiographer's responsibilities is to prevent the spread of healthcare-associated infections. In interventional radiology, this means working with aseptic technique. Surgical face mask protection has been the standard of surgery for a century, but in interventional radiology there are no national guidelines for its use, even though the sterile technique is the same. Aim: The aim of this study was to clarify whether surgical face masks prevent infection in patient in interventional radiology. Methodology: A literature review (Friberg, 2017) has been done to identify the current knowledge in the field. The study includes twelve quantitative articles collected through a systematic literature search in PubMed. After quality review the articles were analyzed and presented into two main categories. Result: Concerning postoperative wound infections, there is no strong evidence to prove that using surgical face masks prevents infections during surgery or coronary angiography. However, using such mask prevents the spread of bacteria to some extent. Conclusion: Research on oral protection is limited, making it difficult to draw any conclusions. A set of new tests are needed to identify the effect of using mask in today’s interventional radiology. Based on the results of the studies, it can be concluded that: generally, mouth protection within interventional radiology should not be mandatory. However, each radiology department need to consider the operating condition and status of the patient and decide if the personal should follow mouth protection process.  

  • Hämquist, Susanna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Processens påverkan på rakhet hos bandstål: Från inkommande råmaterial till färdigt halvfabrikat2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been carried out during the spring of 2017 at Bergsskolan in Filipstad, in cooperation with voestalpine Precision Strip in Munkfors. The demands to produce as cost-effectively as possible is increasing as well as demands to minimize the amount of discarded materials and at the same time maximize customer satisfaction. To achieve this, the company must have an understanding for the mechanisms that influence the defects. The purpose of the thesis is to document the production steps of the strip steel process, from raw materials to processed steel. Doing that the goal can be achieved, i.e. to find the parameters that influence the strip steel's straightness, specifically the so-called camber. There are two types of straightness which causes problems and the important one in this thesis is the so-called camber.

    The material studied was three different strips of the same steel (UHB20C) which were all supposed to move on to the department CCB (Coated Coater Blades). But to proceed, the material must be perfectly straight. The tolerance is as small as +/-33 microns, which often means that the strip looks straight even when there is a straightness deviation. If so, the material may be used in a different application and occasionally it will be scrapped.

    To identify the mechanisms the strip steel was exposed to, the theoretical approach “the seven QC-tools", was used. This is a theory usable when quality improvements are demanded. The work begun with literature studies, however, it was very difficult to find studies and other literature that discussed camber in cold-rolled strip steel. In addition to literature some information was obtained through conversations with the staff in Munkfors. This led to better understanding about the problem.

    Afterwards it was time to draw a chart over the causes effecting the camber. Five parameters were identified as important and was chosen for closer looking. The parameters studied more closely were:

    • ·        transverse profile
    • ·        reductions done in the three different rolling mills
    • ·        contact length and materials in the work roll
    • ·        slitter scorer (the machine that slits the material)
    • ·        human influence

    Then a flow chart of the entire process was drawn up. There are several alternative answers to the problem this paper is trying to solve. The answer could be among the parameters studied but it may as well be found among causes not studied. For example friction, lubricants or the heat treatment the material is exposed to.

    Due to all measurements done in this study there is one parameter most likely to be the cause of camber, the slitter scorer seems to influence the material straightness most of all. Though it is not cleared why the slitter scorer affects the camber more than the other production steps. It could be caused by human influence, it is a machine where very small mistakes, probably unconscious, can lead to big consequences. It may also be due to malfunction of the machine.

    Rolling is a craft which means that the person working at the rolling mill, and the other machines in the production process, has a big influence on final outcome. Voestalpine Precision Strip could probably gain a lot by having detailed setting schedules and measuring instruments that would help the staff doing the exact same thing every time. Hopefully the outcome would not fluctuate as much as it does in the current situation.

  • Lakso, Nina
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Sandin, Petra
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Sjuksköterskors upplevelser av palliativ vård i hemmet: En litteraturstudie2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Palliativa vårdens huvudsakliga mål är att lindra smärta och plågsamma symtom, bekräfta livet samt varken påskynda eller fördröja döden. Samtidigt ska psykologiskt, socialt och andligt stöd kunna erbjudas både patienten och dennes familj. Att vårda en patient med palliativ diagnos i dennes hem kan ställa höga krav på sjuksköterskans yrkeskompetens. Syftet med litteraturstudien var att beskriva sjuksköterskors upplevelser av palliativ vård i hemmet. Författarna till litteraturstudien använde sig av kvalitativ manifest innehållsanalys med en induktiv ansats. Studien baserade sig på tretton vetenskapliga artiklar. Analysen resulterade i sex kategorier, att en god relation till patient och närstående är centralt, att hemmet som arbetsmiljö är komplext, att palliativ vård väcker känslor, att stöd från kollegor spelar en viktig roll, att det krävs en bra arbetsledning och att grunden till god palliativ vård är kunskap, utbildning och erfarenhet. Sjuksköterskors upplevelser av palliativ vård i hemmet visar att det kan vara komplext samt att det finns ett ökat behov av undervisning och förståelse för både arbetsledning och vårdpersonal inom ämnet. Det är viktigt att få kunskap om hur sjuksköterskor upplever vård av patienter med palliativ diagnos i hemmet. Detta för att på ett professionellt sätt kunna bemöta och vårda patienter i livets slut. Ytterligare forskning behövs dock inom stöd, utbildning och kompetensutveckling för sjuksköterskor inom palliativ vård i hemmet.

  • Lundmark, Marie
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Sjuksköterskors upplevelser av att vårda patienter med substansbrukssyndrom: En litteraturstudie2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Substansbrukssyndrom är vanligt förekommande i hela samhället och patienter med substansbrukssyndrom möter sjuksköterskan inom både öppen- och slutenvården. Syftet med denna litteraturstudie var att sammanställa kunskap om sjuksköterskors upplevelser av att vårdapatienter med substansbrukssyndrom. Studien utfördes i form av en kvalitativ innehållsanalys med manifest ansats där 7 vetenskapliga artiklar inkluderades och granskades, vilket resulterade i tre huvudkategorier; Att stöd, förståelse och delaktighet främjar återhämtning, att bristande kunskap, misstro och brist på tillit är hinder för att bedriva en god vård samt att inse att drogen är både patientens bästa vän och värsta fiende. Resultatet visade att faktorer som medkänsla och förståelse hos sjuksköterskan är resurser för att bedriva en god vård som främjar patientens återhämtning. Resultatet visade även att sjuksköterskor upplever ett behov av mer kunskap och erfarenhet gällande substansbrukssyndrom för att överkomma hinder i vården. Sjuksköterskor påverkades av mötet med patienter med substansbrukssyndrom då detta är en komplex sjukdom med många sidor. I relationen mellan sjuksköterska och patient finns omvårdnadens kärna och relationen behöver därför ses som det centrala och grundläggande för att främja en god vård. Genom större kunskap om substansbrukssyndrom och en medvetenhet i form av reflektion av det egna förhållningssättet i relation till patienten kan vården förbättras.

  • Yousef, Caroline
    et al.
    Luleå University of Technology, Department of Health Sciences. Caroline Yousef.
    Kölhi, Anna
    Luleå University of Technology, Department of Health Sciences.
    Hur personer med Hiv upplever bemötandet med hälso-och sjukvårdspersonalen: En litteraturstudie2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Hiv innebär stora förändringar i livet, personer som lever med hiv lever ofta med en ständig rädsla, lidande, osäkerhet och ångest. Lidandet kan vara kopplat till ohälsa, biverkning av behandling men kan även vara orsakad av vården genom kränkande bemötande, utebliven vård eller vård skada.Syftet med denna studie var att beskrivahur personer med hiv upplever bemötandet med hälso-och sjukvårdspersonalen. Genom att analysera tio vetenskapliga studier enligt en kvalitativ manifest innehållsanalys fann vi svar på vårt syfte.I resultatets tre kategorier framkom det att personer med hiv upplevde en ständig diskriminering vid bemötandet med hälso-och sjukvårdspersonal, att personerna fick möta vårdpersonalens rädsla för smitta och fördömande samt en upplevelse av att bli sedd, bekräftad vid mötet samt att man var tvungen att skaffa sig egenmakt vid mötet med hälso-och sjukvårdspersonal. Att belysa, utbilda hälso-och sjukvårdspersonal samt att öka medvetenheten om vårdpersonalens egna attityder möjliggör kan skapa ettbättre och mer personcentrerat omvårdnadför personer som lever med hiv.

  • Hartwig, Marie
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Effects of Weathering on Thermally Modified Softwoods with different Surface Treatments2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master’s thesis studies the effect of weathering on thermally modified Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) with different surface treatments. Most importantly colour changes were analysed, especially, the greying. However, other aspects of appearance changes, like cracks, mould and chemical changes on the surface were included. Special emphasis was on analysing the influence of tree species, type of thermal modification and surface treatment on these properties. Furthermore, it was tested if near infra-red (NIR) spectroscopy allows to estimate the colour, in addition, to measuring chemical changes.

    The whole study was set up as a decking of a gangway in Northern Sweden and evaluated after the first year of exposure. With the help of colorimetry, changes in colour based on the CIE L*C*hab colour space were measured. Test results showed that within one year all surfaces turned greyer significantly due to changes in content of lignin and cellulose measured with NIR spectroscopy. Differences could neither be observed between the uses of the two tree species nor between the uses of the thermal modifications, pressurised saturated steam at a temperature of 180 °C and superheated steam at a temperature of 212 °C. However, the surface treatment affects the colour change. Timber treated with a silicon based treatment had from the beginning a greyer colour and turned greyest after one year, while oil and pigmented oil stain slowed down the greying compared to untreated and iron vitriol treated timber. After one year of exposure for none of the treatments the colour had stabilised.

    Qualitative analysis of cracks and mould growth on the surface indicated some dependence on thermal modification and surface treatment. The PLS model for the prediction was not good, so no universally valid conclusions could be drawn of them. Timber with silicon based treatment showed a tendency for mould growth and timber thermally modified with pressurised saturated steam at a temperature of 180 °C tends to have cracks more often.

    It was possible to estimate the colour from NIR spectroscopy. Best estimations were achieved for the Chroma, followed by lightness and hue. Even better prediction of the Chroma could be achieved by fitting different models based on the surface treatments.  Hence, NIR spectroscopy allows a good estimation of the greying without needing a further measurement instrument, like a colorimeter.

  • Näsström, Max
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Weather Station: Design of a portable & self-sufficient weather station for the Swedish Sea Rescue Society2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Swedish Sea Rescue Society (SSRS) is a non-profit organization that performs sea rescue operations around Sweden’s coast line and lakes. In their sea rescue work, they came up with an idea that could be used to prevent accidents that are caused by harsh weather. According to Trafikverket, two out of three accidents at sea can be related to bad weather.

    Today, the SSRS have a weather application that you can download and note the weather where the different national weather stations are located. The data for this application is gathered from SMHI and YR.no. The SSRS wants to complement this data with their own weather measurements from specific places in e.g. the archipelago. To be able to do this they want to develop a portable and self-sufficient weather station.

    The weather station will be overseen by the SSRS rescue personnel, who will transporting and installing the weather station onto specific place. The weather station shall express the SSRS design profile, blend into the environment, and be easy to transport and install.

    The SSRS doesn’t have any prior products of that sort, and through a market study of competing or similar products / ideas, it became clear that this product would be innovative. By studying the environment which the weather station will be placed and faced with, and who the different users are and their requirements, a requirement framework was established which the end result would need to fulfil. 

    Through different methods and analysis of what people from different background think and feel about the archipelago, a joint view of what the archipelago associates with was established in order for the weather station to be designed to t into the desired environment. Studies and innovation around technical functions that the weather station should be able to perform, have led to different design restrictions in order for the weather station to be able to work.

    The end result of the project is a concept of a self-sufficient and portable weather station, making it possible to be transported and installed by one person. The design of the weather station has been made to make it blend into the environment and up close be able to identify as a product of the SSRS. The design has also been made to be user friendly for those handling it.

  • Fredriksson, Daniel
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Kartläggning av partikelstorleksfördelningar med varierande parametrar vid spraytorkning2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • Sjöblom, Rolf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Reducing risk and uncertainty associated with nuclear waste processing and disposal: a Hanfort tank waste study2018In: Materials Research Society, 2018 Fall Meeting & Exhibit, ET15: Scientific basis for nuclear waste management: Perspectives on strategy, risk and uncertainty in radioactive waste management, Materials Research Society, 2018, Vol. ET15.01, article id ET15.01.04Conference paper (Refereed)
    Abstract [en]

    Carolyn Pearce1 David Peeler1 Rolf Sjöblom2 Mark Triplett1 Kirk Cantrell1 Robert Moore1 MichaelSchweiger1 Vicky Freedman1 Matthew Fountain1 Sue Clark1 Albert Kruger3

    1, Pacific Northwest National Laboratory, Richland, Washington, United States2, Luleå University of Technology, Luleå, , Sweden3, U.S. Department of Energy—Office of River Protection, Richland, Washington,United States

    The Department of Energy’s Environmental Management cleanup effort is focusedon developing and implementing innovative and high impact technologies andsolutions that positively impact the overall mission lifecycle by: (1) reducing lifecyclecosts; (2) accelerating lifecycle schedules; (3) mitigating mission uncertainties,vulnerabilities, and risks; and (4) minimizing the mortgage associated with longterm,post-closure and post-completion stewardship. Pacific Northwest NationalLaboratory and its partnering institutions, are focused on reducing risk anduncertainty across the integrated flowsheet which includes safe waste storage,retrieval, pretreatment, immobilization, disposal, and tank closure. In thispresentation, an overview of the major Hanford flowsheet unit operations will beprovided and examples of specific projects focused on reducing risks anduncertainties will be explored.For example, a key issue of Hanford tank waste processing and disposal is that,although radionuclides (e.g., technetium) drive the disposal risk for the low-activityflowsheet, the presence of ‘benign’ elements (e.g., aluminum) dictate processinglimits or rates in both retrieval and pretreatment unit operations and have otherpotential downstream negative impacts. Thus, safe, cost-effective, and efficient wasteprocessing depends on a fundamental understanding of aluminum chemistry in highionic strength, highly alkaline solutions where water activity is low. Once the wastehas been retrieved, processed, and immobilized, controlling the behavior of riskdriving elements (e.g., Tc and/or I for low-activity waste) in the waste form and theenvironment becomes essential for waste form disposal or tank closure.With respect to low-activity waste form disposal, material solutions mustdemonstrate that the risk driving radioactive elements will be contained in a mannerwholly consistent with statutory requirements. Modelling future performanceremains a challenge for performance assessment (PA) formalism. An appealingoption is to perform an inverse PA (IPA) and look far into the past. Archeologicalartifacts, analogous to wasteform materials (i.e. glass and concrete) that have beenleft by our ancestors and exposed to the environment for thousands of years can beused to check for comprehensiveness as well as to validate and refine predictedwasteform durability. An IPA describes the features, events and processes that haveinfluenced the corrosion of a material over time and can help establish the mostlikely scenarios that should be included in PA for the future. An IPA for ancient glassfrom a hillfort at Broborg, Sweden (ca. 400-575 AD), used to fortify the fort wallswill also be one of the key focal points of this presentation.

  • Manderstedt, Lena
    et al.
    Luleå University of Technology, Department of Arts, Communication and Education, Education, Language, and Teaching.
    Palo, Annbritt
    Luleå University of Technology, Department of Arts, Communication and Education, Education, Language, and Teaching.
    Bildens status i läsarkommentarer på nätet: Narrativ interaktion i Jakob Wegelius Legenden om Sally Jones och Mördarens apa2018In: Barnboken – Journal of Children's Literature Research, ISSN 0347-772X,, Vol. 41Article in journal (Refereed)
    Abstract [en]

    The award-winning novels Legenden om Sally Jones (2008; The Legend of Sally Jones, 2018) and Mördarens apa (2014; The Murderer’s Ape, 2017) written and illustrated by Jakob Wegelius present a thought-provoking interplay between verbal and visual narration. However, an online data collection of blog posts and online reviews reveals that readers discuss the verbal narration and intersectional themes in these novels, but often overlook the pictures.

    This study contributes to the discussion of narrative interaction by juxtaposing analyses of pictures in the novels and online comments by readers on these literary works. The material thus consists of comments by non-professional writers, and the degree and type of attention paid to narrative interaction in these comments is foregrounded. In order to examine the word/image interaction in Wegelius’ novels, Maria Nikolajeva and Carole Scott’s typology for interaction is used on a selection of images and, when possible, on readers’ responses to these novels.

    The results show that in the material, the verbal narration is privileged. Less than a third of the online material explicitly comments on the visual narration. Even fewer readers comment on the relationship between the verbal and the visual narration. The study presents potential explanations to the relative absence of comments on the visual narration in these literary works. A likely explanation is that the readers perceive the symmetrical and enhancing relation between the verbal and the visual narration, and, thus, the readers consider the visual narration redundant or an add-on. Therefore, the article highlights the continuous need for explicit training in visual literacy, as the interaction between words and images has a bearing on the narration.

  • Chabuk, Ali
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Department of Environment Engineering, College of Engineering, University of Babylon, Babylon, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Alkaradaghi, Karwan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Kurdistan Institution for strategic studies and scientific Research, Sulaimaniyah, Iraq.
    Al-Rawabdeh, Abdulla Mustafa Muhamed
    Abdullah Mustafa Muhamed Al-Rawabdeh, Department of Earth and Environmental Science, Yarmouk University, Irbid, Jordan.
    Laue, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Hussain, Hussain Musa
    Remote Sensing Center, University of Kufa, Kufa, Iraq; Department of Geology, Faculty of Science, University of Kufa, Kufa, Iraq.
    Pusch, Roland
    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.
    Landfill Final Cover Systems Design for Arid Areas Using the HELP Model: A Case Study in the Babylon Governorate, Iraq2018In: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 10, no 12, article id 4568Article in journal (Refereed)
    Abstract [en]

    The main purpose of selecting proper designs for landfills is to accommodate quantities

    of waste without having a negative effect on the surrounding environment and human health.

    The Babylon Governorate (province) in Iraq was taken as an example of an arid area with very shallow groundwater and where irregular waste disposal sites had developed that had not been subject to international standards when they were selected for landfill use. In the current study, the suggested design for landfills is a base liner and final cover system. In this suggested design, the final cover system allows for three scenarios. The first scenario considers an evapotranspiration soil cover (ET) (capillary barriers type), the second scenario is a modified cover design of “RCRA Subtitle D”, and the third scenario is a combination of the first and second scenarios. The HELP 3.95 D model was applied to the selected landfill sites in the governorate to check if there was any penetration of the leachate that might in future percolate from the landfill’s bottom barrier layer in arid areas. The results from the suggested landfill design showed that there was no leachate percolation from the bottom barrier layer using the second and third scenarios. For the first scenario, however, there was a small amount of leachate through the bottom barrier layer in the years 2013 and 2014.

  • Westberg, Erik (Conductor)
    Luleå University of Technology, Department of Arts, Communication and Education, Music and dance.
    Arctic Male Voices: Life – premiärkonsert2018Artistic output (Unrefereed)
    Abstract [sv]

    Konsert i Umeå stads kyrka den 18 november 2018 med den nybildade manskören Arctic Male Voices. Kören bildades på initiativ av Erik Westberg efter möjligheten att samarbeta i en workshop med The King´s Singers.

  • Westberg, Erik (Conductor)
    Luleå University of Technology, Department of Arts, Communication and Education, Music and dance.
    Amor Vita Mors2018Artistic output (Unrefereed)
    Abstract [sv]

    Fonogrammet Amor Vita Mors släpptes 18 oktober 2018 och innehåller över två timmar vokalmusik. Amor Vita Mors släppte endast digitalt men till fonogrammet producerades även en bok med texter, verkkommentarer och konceptkonst.

  • Westberg, Erik (Conductor)
    Luleå University of Technology, Department of Arts, Communication and Education, Music and dance.
    Förklädd gud: Sverige möter Israel2018Artistic output (Unrefereed)
    Abstract [sv]

    Turné genom Israel 27 juni – 7 juli i samarbete med trombonisten tillika dirigenten Christan Lindberg och Israel Netanya Kibbutz Orchestra.

  • Westberg, Erik (Conductor)
    Luleå University of Technology, Department of Arts, Communication and Education, Music and dance.
    Vind virvlar till musik: Jubileumskonert – Erik Westbergs Vokalensemble 25 år2018Artistic output (Unrefereed)
    Abstract [sv]

    Turné 18-20 oktober 2018 med konserter i Acusticum (Piteå) Eric Ericsonhallen (Stockholm) och Allhelgonakyrkan (Lund). Framträdandet i Eric Ericsonhallen gjordes i samarbete med Eric Ericson International Choral Centre som en del av deras uppmärksammande av 100 år sedan Eric Ericsons födelse. Konserten i Allhelgonakyrkan gjordes i samarbete med Musik i Syd som en del av festivalen Lund Choral Festival och spelades även in av Sveriges Radio P2.

  • Kumar, TK Sandeep
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Nurni, Viswanathan
    Indian Institute of Technology Bombay.
    Ahmed, Hesham
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Andersson, Charlotte
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Dahlin, Anders
    LKAB.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Investigation of Magnetite Oxidation Kinetics at the Particle Scale2019In: Metallurgical and materials transactions. B, process metallurgy and materials processing science, ISSN 1073-5615, E-ISSN 1543-1916Article in journal (Refereed)
    Abstract [en]

    The induration of magnetite pellets is a complex physico-chemical process that involves oxidation, sintering, and heat transfer. The thermal- and gas-composition profile that is experienced by the pellet in an induration reactor could result in the formation of a homogenous or heterogeneous pellet structure, which could affect the pellet quality. The oxidation kinetics of magnetite pellets from sintering studies have been studied at two levels, namely, the pellet scale and at the particle scale, and the findings of the latter are presented here. The rate of oxidation of the magnetite concentrate depends primarily on temperature, oxygen content in the oxidizing gas, and particle size. These factors are investigated in this study. It was found that the oxidation of the magnetite concentrate is comprised of two distinct stages, a primary stage with high rates followed by a secondary stage where rates decrease significantly. The isothermal oxidation behavior as analyzed by the Avrami kinetic model was found to fit better than the shrinking-core model. The partially oxidized particles were examined microstructurally to supplement the experimental and model results. The Avrami kinetic model for isothermal oxidation was extended to non-isothermal profiles using the superposition principle, and the model was validated experimentally.

  • Blomgren, Johannes
    et al.
    Strandell, Erika
    Jull, Gwendolen
    Luleå University of Technology, Department of Health Sciences, Health and Rehabilitation. Physiotherapy, School of Health and Rehabilitation Sciences, The University of Queensland, St Lucia, Brisbane, Australia..
    Vikman, Irene
    Luleå University of Technology, Department of Health Sciences, Health and Rehabilitation.
    Röijezon, Ulrik
    Luleå University of Technology, Department of Health Sciences, Health and Rehabilitation.
    Effects of deep cervical flexor training on impaired physiological functions associated with chronic neck pain: a systematic review2018In: BMC Musculoskeletal Disorders, ISSN 1471-2474, E-ISSN 1471-2474, Vol. 19, article id 415Article in journal (Refereed)
    Abstract [en]

    Background:Neck pain is a major health issue with high rates of recurrence. It presents with a variety ofaltered sensorimotor functions. Exercise is a cornerstone of rehabilitation and many training methods areused. Exercise is evaluated in most randomized controlled trials on its pain relieving effects. No review hasassessed the effect of exercise on the altered physiological functions or determined if there are differentialeffects of particular training methods. This review investigated the effects of deep cervical flexor (DCF)training, a training method commonly used for patients with neck pain, and compared it to other trainingmethodsornotrainingonoutcomesofcervicalneuromuscular function, muscle size, kinematics and kinetics.Methods:Web of Science, Scopus, CINAHL, PubMed were searched from inception until January 2018. Twelverandomized controlled trials were included that compared DCF training as sole intervention to other trainingor no interventions in persons with neck pain. The Cochrane Risk of Bias tool was used to assess the methodquality. All outcome measures were analysed descriptively and meta-analyses were performed for measuresevaluated in three or more studies.Results:DCF training was compared to cervical endurance, strength, proprioception and mobility training,muscle stretching, and no intervention control groups. Physiological outcome measures includedneuromuscular co-ordination (craniocervical flexion test), functional tasks, muscle fatigability, muscle size,kinematics (joint position sense, posture and range of motion) and kinetics (strength, endurance andcontraction accuracy). Strong evidence was found for effectiveness of DCF training on neuromuscularcoordination, but it had no or small effects on strength and endurance at higher loads. DCF trainingimproved head and cervical posture, while evidence was limited or contradictory for other measures.Conclusions:DCF training can successfully address impaired neuromuscular coordination, but not cervicalflexor strength and endurance at higher contraction intensities. A multimodal training regime is proposedwhen the aim is to specifically address various impaired physiological functions associated with neck pain

  • Tajbakhsh, Mohammad
    et al.
    Regional Water Authority, Zan Blvd., Kermanshah, Iran.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Comparative study of multi-station method and Hershfield’sapproaches for PMP determination: (case study: Northeast of Iran)2018In: Sustainable Water Resources Management, ISSN 2363-5037Article in journal (Refereed)
    Abstract [en]

    The maximum daily rainfall values for 36 homogeneous stations in the northeast of Iran were adopted to estimate the appropriate Probable annual Maximum Precipitation 1-day precipitation (PMP 24) values. PMP24 was found as 128.2–284.2, 62.7–160.2 and 124 mm for Hershfield 1, Hershfield 2 and multi-station approach, respectively. The ratio of PMP 24

    to the highest observed 1-day rainfall was consistent for the second approach of Hershfield. It was in harmony with the multi-station method, but varied widely for Hershfield 1. This may be the result of different record length effect on Hershfield 1 approach. Finally, the map of PMP 24 isochrones was prepared for the second approach of Hershfield for over northeast of Iran.

  • Al-Mamoori, Sohaib Kareem
    et al.
    Department of Environmental Planning, Faculty of Physical PlanningUniversity of KufaNajafIraq.
    Al-Maliki, Laheab A. Jasem
    Department of Hydraulic Engineering Structures, Faculty of Water Resources EngineeringGreen University of Al QasimBaghdadIraq.
    El-Tawel, Khaled
    Faculty of EngineeringLebanese UniversityBeirutLebanon.
    Hussain, Hussain M.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Al Ali, Mohammed Jawad
    Department of Environmental Planning, Faculty of Physical PlanningUniversity of KufaNajafIraq.
    Chloride, Calcium Carbonate and Total Soluble Salts Contents Distribution for An-Najaf and Al-Kufa Cities’ Soil by Using GIS2018In: Geotechnical and Geological Engineering, ISSN 0960-3182, E-ISSN 1573-1529Article in journal (Refereed)
    Abstract [en]

    The main objective of the paper is to create geotechnical maps for three soil chemical properties in An-Najaf and Kufa cities’ soil by utilizing of GIS tools. This properties are the chloride concentration, calcium carbonate (CaCO 3) and total soluble salts where they affect the durability of reinforced structural elements. This paper provides an easy accurate way to represent soil properties levels for different depths of soil and create reliable database that will help engineers and decision makers. The data included in this paper were collected for (464) boreholes with depths up to 35 m distributed on residential areas in all of An-Najaf and Kufa cities. Arc-Map of GIS 10.2.1 was used to produce the maps. It has been concluded that chloride content in the soil of the study area range from - 0.01 to 0.99% and with an average of 0.5. The maximum value found in at depth 4–6 m while the minimum value found in location at depth 4–6, 8–10 and 14–16 m. The chloride content in most of An-Najaf province has exceeded the permissible limit and for all, this required taking percussions to protect foundations. While calcium carbonate content in the soil of the study area range from 53 to 0.18 and with an average of 26.6. The maximum and the minimum values found at depth 4–6 m. Calcium carbonate content is within the permissible limits in most locations except in some locations.

  • Väyrynen Chytiris, Ion
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Flygskatten: En studie om måluppfyllelse, kostnadseffektivitet och incitament till teknologisk utveckling2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    On the 1st of April 2018, the Swedish government implemented a flight tax in Sweden with the goal of reducing the Swedish aviation industries atmospheric emissions. With the help of the theory of microeconomics, earlier studies, statistics, calculations, and comparisons based on secondary data, the essay analyzes the Swedish flight tax with regards to its achievement of the environmental objectives, cost-efficiency and, incentives to technological development. The essay reaches the conclusion that the current design of Swedish flight tax does not achieve the requirements of cost-efficient regulations, does not promote further incentives to technological development beyond the already established European Union Emission Trading System and does not meet the environmental objectives nationally nor internationally.

  • Hellberg, Ellinor
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    “Ingen väntar mästerskap av den som börjar”: Socialdemokratiska kvinnodistriktets tidiga organisering i Norrbotten år 1933 - 19362018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • Johansson, Frida
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Kommunister i norr: En studie om kommunismen i Pajala kommun före och efter andra världskriget2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • Nyberg, Maria
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences. Maria Nyberg.
    "Bron som aldrig byggts": En undersökning av samhällsdebatten angående bron till Sandön i Luleå skärgård år 1960-2018.2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • Still, Vincent
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering. Space Structures GmbH.
    Thermal Control Design and Simulation of a Space Mission2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The following document describes an example mission, which originated from a real life concept of an imaging satellite in a Sun Synchronous Orbit (SSO)around Earth. This report takes the reader through the thermal analysis and evaluation of space equipment performed with Airbus Space & Defence’s Systema/Thermica tool, at Space Structures GmbH. It details the full process of designing a thermal control system for a space project. The project started from a CAD file which was converted into a Geometric Mathematical Model (GMM) inside Thermica. This process requires an extensive knowledge of not only the software, but also the technical background behind what happens to a satellite in such an extreme environment. This thesis addresses this by showing a step-by-step approach of a full thermal evaluation, starting with the required theoretical background of the thermal environment and the different passive and active thermal design techniques. The next step involves gathering the required input information for the software; such as defining the conductance values between the components and calculating the per node power dissipation for each component considering each operational mode. The final step includes the designing, simulation, iteration and presentation of the temperature results across the spacecraft thermal model. The results of the initial simulation showed that some sensitive components were not within the specified temperature requirements, and therefore both radiators and heaters were sized and introduced to the model. After the third iteration of thermal control, the sensitive components’ temperatures were observed to be within the allowable margins of an ECSS Phase A study. This thesis can serve as a guide and complete document for future missions which plan the design of a Thermal Control System of a satellite in orbit around Earth.

  • Runardotter, Mari
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Päivärinta, Tero
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Smarta hållbara byar i Övre Norrland: Användarnas perspektiv2018Report (Other (popular science, discussion, etc.))
  • Runardotter, Mari
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Gylling, Arne
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology.
    Lindberg, Johanna
    Region Norrbotten.
    Päivärinta, Tero
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Tingström, Johan
    iTid Tarinfo AB.
    Ylinenpää, Roger
    Luleå kommun.
    Smarta hållbara byar i Övre Norrland: Förstudie – nuläge och framtid2017Report (Other (popular science, discussion, etc.))
  • Wu, Bo
    et al.
    School of Physics and Electronic Science, Zunyi Normal University, Zunyi, China; School of Marine Science and Technology, Northwestern Polytechnical University, Xi’an, China.
    Huang, Haishen
    School of Physics and Electronic Science, Zunyi Normal University, Zunyi, China; School of Physics, Beijing Institute of Technology, Beijing, China.
    Zhou, Guangdong
    Guizhou Institute of Technology, Guiyang, China.
    Feng, Yu
    School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou, China.
    Chen, Ying
    School of Mathematics and Physics, Anshun University, Anshun, China.
    Wang, Xiangjian
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Structure, Magnetism, and Electronic Properties of Inverse Heusler Alloy Ti2CoAl/MgO(100) Herterojuction: the Role of Interfaces2018In: Applied Sciences, E-ISSN 2076-3417, Vol. 8, no 12, article id 2336Article in journal (Refereed)
    Abstract [en]

    In this study, the interface structures, atom-resolved magnetism, density of states, and spin polarization of 10 possible atomic terminations in the Ti2CoAl/MgO(100) heterojunction were comprehensively investigated using first-principle calculations. In the equilibrium interface structures, the length of the alloy-Mg bond was found to be much longer than that of the alloy-O bond because of the forceful repulsion interactions between theHeusler interface atoms andMg atoms. The competition among d-electronic hybridization, d-electronic localization, and the moving effect of the interface metal atoms played an important role in the interface atomic magnetic moment. Unexpected interface states appeared in the half-metallic gap for all terminations. The "ideal" half-metallicity observed in the bulk had been destroyed. In TiAl-Mg and AlAl-O terminations, the maximal spin polarization of about 65% could be reserved. The tunnel magnetoresistance (TMR) value was deduced to be lower than 150% in the Ti2CoAl/MgO(100) heterojunction at low temperature.

  • Gunnarsson, Niklas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Mineralogical speciation of sulfur in acid sulfate soils from Luleå, Sweden2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Marine sulfide – bearing sediments that oxidize when in contact with oxygen and leach outelements in high concentrations to small watercourses have been a problem for many years allover the world especially around the Bothnian Bay. The purpose of this study was to furtherinvestigate the sulfur mineralogy present in acid sulfate soils in the area of Luleå, Sweden. Asecondary aim was to see if elements leach out and accumulate in an acid sulfate soil closer tothe recipient. Samples were taken in two profiles (one oxidized and one waterlogged) fromfour sites (sites A-D) and were analyzed for whole rock geochemistry. Two sites were furtherinvestigated for mineralogy in polished samples with an optical microscope, Ramanspectroscopy and SEM-EDS. Each profile consisted of three layers: oxidation zone, transitionzone and reduced zone. The oxidation zone above the groundwater table was light grey withbrown iron hydroxide staining. Parts that lied under the water table were dark grey-black within general strong odor (“rotten eggs”) due to its sulfur content. It was usually straightforwardto distinguish and separate the layers from each other directly in the field, however in somecases pH was needed for confirmation.A general feature of investigated polished samples is the presence of abundant framboidalpyrites that are common in reduced marine sediments. The transition zone was formed in suboxicconditions and this feature is reflected by the mineralogy. Many morphologies of theframboidal pyrite were observed in this layer and signs of both dissolution and formationoccur. In the sample from site C one could observe elemental sulfur in form of large (up to 50μm) euhedral crystals. In the samples with pH<4, no sulfides occur as they have been replacedby jarosite (site B). Site C lacks these sulfur-bearing hydroxides which is thought to be due toa sulfur concentration of <0.2 %. Sulfur shows extensive leaching at most sites but at site B andD1, it accumulates in the transition zone. Elements like cobalt (Co), nickel (Ni) and zinc (Zn)are leached out or are accumulated further down in the profile. Elements that could have beentransported and have accumulated in the waterlogged profiles are Co, Ni, Zn and chromium(Cr) and in some profiles also copper (Cu) and vanadium (V).

  • Holmgren, Carl
    Luleå University of Technology, Department of Arts, Communication and Education, Music and dance.
    A Philosophic Poetic Inquiry of Three Aspects of Interpretation within Music Education Research: An Autoethnodrama in Four Acts2018In: European Journal of Philosophy in Arts Education, ISSN 2002-4665, Vol. 3, no 1, p. 7-86Article in journal (Refereed)
    Abstract [en]

    This article explores three aspects of interpretation—musical interpretation of notated Western art music, hermeneutics (theoretical framework), and poetry (tool for analysis and representation)—based on ongoing music education research focusing on the learning of musical interpretation within the one-to-one context of higher music education. The broad philosophic poetic inquiry of interpretation has the form of an autoethnodrama containing both haiku and found poetry. Poetry is both used as a process of inquiry and as a means of representation. The autoethnodrama explores the author’s struggle with finding his cogito for conducting arts-based research and touches upon his personal history. Through the combination of autoethnodrama and a philosophic poetic inquiry, he finds a deeper understanding of musical interpretation, usage of poetry and autoethnodrama in research, as well as of his personhood. Concluding reflections on one possible way of interpreting the autoethnodrama in relation to teaching and learning of musical interpretation within higher music education are also presented.

  • Sandberg, Linnéa
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Klimatsmart livsstil: Hur människor kan påverkas till att leva mer klimatsmart2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    One of the greatest challenges of our time is the ongoing climate change. Research suggests that it is us humans that through our greenhouse gas emissions are the greatest cause of globalwarming and the problems that comes with it. To reduce the emissions of greenhouse gas and meet the international goals, it is necessary for individuals to make changes in their behavior.

    Some people care a lot about the climate and tries to do everything in their power to lower theirown impact, others want to do something but do not know what and some people does not care at all. The purpose of this study is to provide a deeper understanding of how to influence people to live in a more environmentally friendly way by identifying factors that determines environmentally friendly actions both positively and negatively.

    The study was conducted through a qualitative case study where the data collection was made through personal interviews with citizens in Luleå. The results of the study show that knowledge has a strong connection to individual behaviors. It is important to know that the environmental actions you take is of importance. Many people have the desire to do more than they do but are hindered by contextual factors like saving time. Except for the factors that was identified in the frame of reference the study also shows that there are other reasons for individuals to act in an environmentally friendly way: health, economy, ethics, frugality and care about future generations.

    By identifying these factors and get an explanation of how they impact individuals, the study can aid decision makers of a county with information that helps them adapt their conversion work to the citizens. The recommendations for counties are to provide citizens with clear information both regarding what goals they aim to reach as well as concrete actions to take in order to fulfil these, make it easier to choose environmentally friendly options, market the environmental benefits but also other reasons for certain behaviors since many people are more motivated byother things than environmental reasons, share their results in their environmental work to include citizens as well as spread motivation for further behavior changes.

  • Johansson, Paulina
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Hålrumsvariationer vid asfalttillverkning: En fallstudie vid Skanska enligt DMAIC avseende förbättringsmöjligheter vid kalltillsatt asfaltåtervinning2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Optimizing void volumes are essential for the serviceability of asphalt concrete pavements, as fatigue cracking, rutting and other permanent deformations can be caused by e.g. temperature changes (Monismith, 1992). Since both reclaimed asphalt pavement (RAP) and virgin asphalt concrete consist of mineral aggregate, bitumen and additives, RAP is worth the virgin material it replaces ton for ton (Brock & Richmonds, 2007). As the use of RAP becomes more and more popular, the complexity of asphalt manufacturing increases (Karlsson & Isacsson, 2006). This, because the recycled material is harder to characterize than virgin material. Since the usage of RAP is expected to increase in hot-mix asphalt (HMA), while little research has been made in the field of cold feed RAP, it is of great importance to investigate the void volumes with this method. During this study, ABT11 160/220 with the addition of up to 25% cold feed RAP was therefore investigated.

    Six Sigma’s project improvement methodology DMAIC, acronym for the five phases define, measure, analyze, improve and control, were used to get an in depth understanding for the variations in void volumes. In this method, Statistical Process Control and Design of Experiments were used to answer the research purpose, which was to investigate and evaluate the reasons to why void volumes during asphalt manufacturing varies when adding cold RAP and give recommendations for an improved production regarding void volumes.

    After an investigation of historic data, calculations, interviews and observations, the most important causes for variations in void volumes came from data collection, communication, resource management, material knowledge and organizational culture, where the last two are seen as root causes. Because of the research delimitations, only the material knowledge was looked into further. To extend the knowledge of the material, the factors RAP, virgin bitumen, virgin filler, manufacturing temperature and temperature for Marshall testing were analyzed through two experiments. In the first experiment, the relationship between void volumes and the temperature for Marshall testing were investigated through an OFAT study, and the second experiment was made through a 24-1 factorial design according to Split plot, in which the void volumes were measured through the normal Marshall testing temperature (135 ˚C) and through a road simulation.  The OFAT result showed that a third degree linear relationship is present between the void volumes and the Marshall testing temperature, with large changes for temperatures lower than 125 ˚C and greater than 145 ˚C. This entails an increased importance of controlling the temperature for warm-mix asphalt (WMA) and asphalt with increased volumes of RAP. The Split plot experiment showed that also bitumen and RAP are significant effects for the void volume, where decreased volumes of bitumen and increased volumes of RAP entails higher void volumes in the pavement. Over 15 % RAP also entails greater void volumes.

    To decrease the causes for variations in void volumes, the recommendation is to collect, evaluate, communicate and follow up data at a higher extent through implementation of statistical process control, value flow analysis and continued material studies. The organizational culture ought to be changed to create an understanding of the recommended methods. If the recommendations are followed, estimated economic savings of 11 520 000kr/year can be a reality, as well as environmental benefits of e.g. a decreased use of finite resources and reduced CO2 emissions.