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  • Szymaszko, Lydia
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Sundström, Linnea
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Personers upplevelser av hur diabetes typ 1 påverkar det vardagliga livet: En litteraturstudie2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Diabetes typ 1 är en kronisk sjukdom som drabbar främst barn och ungdomar. Enligt World health organisation (WHO) hade 422 miljoner diabetes i världen år 2016 varav 10–15% består av diabetes typ 1. Att leva med kronisk sjukdom har ofta en påverkan och förändrar människors liv. Syftet var att beskriva personers upplevelser av hur diabetes typ 1 påverkar det vardagliga livet. Totalt analyserades tio artiklar med kvalitativ innehållsanalys med manifest ansats för att beskriva personers upplevelser enligt Bengtssons (2016) metod. Den kvalitativa innehållsanalysen resulterade i fem slutkategorier som var: Att känna sig begränsad i sina dagliga aktiviteter; Att behöva speciella rutiner och inte kunna vara spontan; Att känna sig annorlunda och beroende av andra; Att känna frustration över att möta okunskap hos omgivningen; Att känna sig orolig över vad som kan hända. En slutsats var att personer med diabetes upplevde svårigheter att leva ett normalt vardagsliv. De mötte okunskap kring sjukdomen vilket medförde att de kände sig annorlunda och därmed en skam över att leva med diabetes. Studien visade att det finns en bristande kunskap i samhället om diabetes typ 1.

  • Pettersson, Isabell
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Samverkansbjälklag vs. Håldäck: En jämförelse av miljöpåverkan och byggfysikaliska aspekter2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • Åsander, Sandra
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Undersökning av kolhalten i ett plastformsstål under tillverkning i ljusbågsugnen2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete har utförts på Uddeholms AB i Hagfors i syfte med att undersöka möjliga orsaker till uppkolning av smältan under tillverkning av ett lågkolhaltigt krom-manganstål i ljusbågsugnen. Totalt följdes sju charger upp vid nedsmältningen i ljusbågsugnen. Provtagning av stål, slagg och skrot utfördes under processen. Dessutom undersöktes effekten av syrgasfärskning samt grafitelektrodernas inverkan på kolhalten. Resultatet för varje undersökt parameter har utvärderats och kopplats till teorin, med syftet att genom möjliga samband erhålla förslag till en processföring där behovet av syrgasfärskning för reducering av kolhalt i ljusbågsugnen kan undvikas.

    Projektet har behandlat en process där många faktorer kan inverka på uppkolningen av smältan. Dock kan ett samband mellan höga kolhalter och tillsatser av skrotet CrNi-rusor ses. På majoriteten av charger med för hög kolhalt tillsattes detta skrot. Dåliga grafitelektroder uppvisar också en tendens att bidra till uppkolning av stålsmältan.

    Syrgasfärskning tenderar att oxidera större mängder krom och mangan till slaggen, vilket leder till ökade legeringskostnader per tillverkad charge.

    Den främsta anledningen till de för höga kolhalterna har med stor sannolikhet berott på en kombination av tillsatt skrot med för hög kolhalt samt användning av dåliga elektroder under nedsmältning. Vidare uppföljning av elektroderna och kontroll av skrotet för att minimera uppkolning kvarstår för framtida arbete.

  • Public defence: 2018-05-02 18:45 Luleå tekniska universitet, D2222, Luleå
    Farhadova, Nilufar
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Örnblom, Julia
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Kvinnors upplevelser av det dagliga livet efter hjärtinfarkt - en litteraturstudie2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Att drabbas av hjärtinfarkt innebär en stor förändring i det dagliga livet. Sjukdomen påverkar de drabbade på olika sätt och kvinnors och mäns upplevelser efter en hjärtinfarkt skiljer sig åt. Syftet med denna litteraturstudie var att beskriva kvinnors upplevelser om det dagliga livet efter en hjärtinfarkt. Litteraturstudien var baserad på femton vetenskapliga studier som analyserades enligt Bengtssons metod för kvalitativ innehållsanalys. Resultaten beskrevs i fem kategorier: att inte känna igen sin kropp och förlora sin självständighet, att känna sig begränsad och rädd för att återinsjukna, att behöva stöd för att få en gynnsam hälsoprocess och ett ökat välbefinnande, att behöva kontinuitet och känna sig förberedd och att hitta mening och nya strategier för att få balans i det nya livet. Resultatet visade kvinnors upplevelser runt det dagliga livet efter hjärtinfarkten. Stöd från hälso- och sjukvårdspersonal är viktig för hur kvinnorna klarar av sin situation. Slutsatsen var att vårdpersonalen måste arbeta personcentrerat med hänsyn till kvinnornas individuella behov för att ge bättre vård till kvinnor som genomgått en hjärtinfarkt.

  • Fethi, Hemayon
    Luleå University of Technology, Department of Health Sciences.
    Sjuksköterskors upplevelser av att vårda patienter i livets slutskede En litteraturstudie2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Palliativ vård innebär för individen att det inte längre finns möjlighet att bli botad. Denna vårdform räknas som en viktig vård-filosofi med egen specifik kunskap. Grundstenarnaär omhändertagande och vård av den drabbade individen för vilken lindrande vård blir aktuell i livets slutskede. Syftet med studien var att beskriva sjuksköterskors upplevelser av att vårda patienter i livets slutskede. För att kunna beskriva sjuksköterskors upplevelser används metoden kvalitativinnehållsanalys medinduktiv ansats.Analysen resulterade i fem kategorier: Att bli känslomässigt berörd; Att känna sig obekväm; Att känna sig otillräcklig; Att se närvaro och fysisk beröring som betydelsefullt samt Att se palliativ vård som givande och tillfredsställande.Resultatet visade att ett gott teamarbete förhindrades av tidsbrist och underbemanning men underlättades av stöd från kollegor och positiv feedback. Sjuksköterskor upplevde även att de kunde känna sig obekväma att arbeta med patienter i ett palliativt skede.

    Nyckelord:Palliativ vård, patient, omvårdnad, sjuksköterska, upplevelser, kvalitativ metod, litteraturstudie.

  • Jaako, Lisa
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Juuso, Sara
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Kvinnors upplevelser av att leva med vestibulit2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Vestibulit anses vara den vanligaste orsaken till smärta vid samlag och drabbar uppskattningsvis 2-5% av kvinnor i 20-30 årsåldern. Det är ett smärttillstånd i underlivet med en inte helt klarlagd etiologi vilket gör att kunskapen samt förståelsen är låg kring ämnet. Syftet med denna litteraturstudie var att beskriva kvinnors upplevelser av att leva med vestibulit. Metoden som användes var en kvalitativ innehållsanalys, detta för att fånga kvinnornas upplevelser, utifrån de fyra frågeställningarna: Hur upplevs den psykiska hälsan när man lever med vestibulit? Hur upplevs sexualiteten när man lever med vestibulit?  Hur upplevs relationer av att leva med vestibulit? Hur upplevs vardagslivet av att leva med vestibulit? Den kvalitativa innehållsanalysen är baserad på fyra bloggar och fem intervjuer av kvinnor som lever med vestibulit. Analysen är utförd systematiskt enligt Bengtsson (2016) genom ett flertal steg som dekontextualisering, rekontextualisering, kondensering, kategorisering och kompilering. Analysen resulterade i elva slutkategorier: att känna sig nedstämd, att känna hopp och hopplöshet, att få ett förändrat självförtroende, att vara i behov av stöd, att uppleva smärta vid samlag, att få en förändrad sexlust, att vilja vara sexuellt aktiv, att erfara hur relationer förändras, att känna sig otillräcklig, att se smärtan som en central del i vardagen och att smärtan utgör ett hinder i vardagen. Resultatet visade att dessa kvinnor påverkas psykiskt, sexuellt, relationsmässigt och i sitt vardagsliv av att leva med vestibulit. Det resulterade i att avstå från en mängd aktiviteter och påverkade kvinnorna och deras livsstil, relationer, sociala kontakter och välbefinnande. Resultatet från denna litteraturstudie kan användas som ett hjälpmedel för sjuksköterskor till att öka förståelsen för hur det är att leva med vestibulit. Det finns ett ökat behov av omvårdnadsforskning inom ämnet för att kunna bedriva en bättre individanpassad vård där man identifierar och tillgodoser dessa kvinnors behov.

  • Ekbäck, Josefin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Framtidens bostäder i Gällivare: En kvalitativ studie om samhällskrav och invånarbehov2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • Nyström, Felix
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Humbla, Christian
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Faktorers påverkan på bostadsbränder: En statistisk analys2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sveriges räddningstjänster åker på cirka 6000 bostadsbränder varje år. Var och en av dessa 6000 insatser är unika och att veta vilken åtgärd som är effektivast vid respektive scenario är oavsett en gedigen kunskapsgrund väldigt svårt. Detta arbete vill genom statistisk analys, försöka kartlägga dessa åtgärder och dess effektivitet och därmed försöka besvara vilka åtgärder som är framgångsrika vid en räddningsinsats samt vilka taktiska upplägg som fungerat bäst i respektive scenario.  

     

    För att besvara frågeställningarna genomfördes en litteraturstudie av tidigare forskning inom området, vilket följdes av en utrensning och sammanställning av materialet utifrån några utvalda kriterier. Utfall för en insats kategoriserades enligt grönt, gult och rött. Fortsättningsvis genomfördes en indelning enligt bostadskategorierna villa, flerbostadshus, rad-/ par-/ kedjehus och fritidshus. Resultatet framställdes sedan genom ordinal regression med Stata, ett program för hantering av statistik.

     

    Resultatet gav att samtliga variabler i de modeller som framställts hade en negativ påverkan på den genomsnittliga sannolikheten för att en insats ska få ett grönt utfall. Dessa variabler hade också en ökande påverkan av den genomsnittliga sannolikheten för en insats med gult eller rött utfall. För villor hade släckning från marken en markant påverkan på utfallen, medan åtgärden skärsläckare var den åtgärd som hade minst påverkan. För flerbostadshus gav åtgärderna dimspik, skärsläckare och håltagning en stor påverkan på de olika utfallen. I rad-/ par-/ kedjehus samt fritidshus hade ett fåtal variabler signifikans, vilket gav ett osäkert resultat.

     

    Vid analys av resultatet visade sig skärsläckare ha den minsta negativa påverkan på utfallet och släckning från marken ha den största negativa påverkan på utfallet vid en räddningsinsats för bostadskategorin villor. De samband som kunde kartläggas gällande flerbostadshus var att de åtgärder som tillsattes vid en stor brandomfattning hade ett sämre utfall än de åtgärder som tillsattes i ett tidigare läge. För rad-/ par-/ kedjehus kunde ett osäkert samband dras där insatser med åtgärden dimspik hade ett marginellt bättre utfall än de insatser som använde åtgärden släckning från marken. Även för fritidshus gavs ett osäkert resultat med endast släckning från marken som förklarande variabel.

    För villa och flerbostadshus skiljer sig variablernas påverkan av utfallet tydligt och detta beror på att åtkomligheten för dessa bostäder kan variera. Vid flerbostadshus finns det svårigheter att angripa en brand på ett effektivt sätt. Den begränsade statistiken för rad-/ par-/ kedjehus och fritidshus är en förklaring varför signifikansen för majoriteten av variablerna var låg och inte kunde användas på samma sätt som de andra bostadskategorierna. För dessa kategorier kunde ingen säker slutsats dras.

  • Ferner, Emma
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Petäjäniemi, Kristina
    Luleå University of Technology, Department of Health Sciences.
    Sjuksköterskors upplevelser av att vårda patienter med dialys: En litteraturstudie2018Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [sv]

    Njursvikt blir allt vanligare omkring i världen och är en påfrestande sjukdom som orsakar många förändringar i personens vardagsliv på grund av dess symtom och behandling. Sjuksköterskan har ett stort ansvar kring dessa patienter både gällande hälsa, behandling och utbildning. Syftet med denna litteraturstudie var att studera sjuksköterskors upplevelser av att vårda patienter med dialys. I studien ingick tio kvalitativa artiklar som analyserades enligt kvalitativ innehållsanalys med manifest ansats. Analysen resulterade slutligen i fem kategorier vilka var; Att ha nära relationer, Ett stressande och krävande arbete, Att känna sig otillräcklig, Svårigheter att utbilda och kommunicera och att bli berörd och vilja ge stöd. I resultatet framkom att sjuksköterskor har nära relationer med patienter som behandlas med dialys och dessa relationer beskrevs som bekväma men kunde även orsaka en känslomässig trötthet. Arbetet upplevdes stressande och krävande på grund av oerfarenhet, sjukdomens komplexitet, arbetsmiljön och den svåra tekniken. Otillräcklighet upplevdes när sjuksköterskorna inte hade tillräckligt med tid, när kommunikationen med läkare var bristande och när patienterna var missnöjda. Att utbilda och stödja patienterna kunde upplevas som svårt, men resulterade i känslor av stolthet när det lyckades. Slutsatsen är att nära relationer med patienterna gör att sjuksköterskor kan ge en bättre vård och se individuella behov. Även patienten upplever en trygghet med en kontinuerlig kontakt. För att minska stress och känsla av otillräcklighet så behövs mer utbildning för sjuksköterskor som arbetar med dialys. Mer forskning inom området behövs då studier inom ämnet är begränsat.

  • Dahlberg, Emma
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Sadinmaa, Marie
    Luleå University of Technology, Department of Health Sciences.
    Interventioner för att lindra oro och ångest hos patienter som vårdas palliativt: -en kunskapsöversikt2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Att befinna sig i livets slutskede ökar risken för psykiskt lidande i form av oro och ångest. Syftet med denna studie var att sammanställa kunskap om interventioner för att lindra oro och ångest hos patienter som vårdas palliativt. Utifrån syftet formulerades tre frågeställningar om vad det finns för interventioner, vem som utför interventionerna samt vad interventionerna gav för effekt. En systematisk litteraturöversikt genomfördes där 19 studier valdes ut att bli granskade och analyserade. Resultatet visade tre huvudkategorier av interventioner, psykologiska-, sinnesstimulerande- och resursstärkande interventioner. Resultatet visade att dem som utförde interventionerna kunde variera mellan olika professioner. Resultatet påvisade också att 18 av 19 studier rapporterade en ångestlindrande effekt av interventionerna. Kunskapsöversikten bidrar till en ökad kunskap över vilka interventioner sjuksköterskor kan erbjuda eller med rätt utbildning utföra för att lindra oro och ångest hos patienter som vårdas palliativt. Kunskapsöversikten kan även användas som en guide till att välja rätt intervention utifrån patientens förutsättningar och önskad effekt. Resultatet av kunskapsöversikten visar att en ökad kunskap om de identifierade interventioner kan bidra till att bredda sjuksköterskans omvårdnadskompetens men även till en holistisk omvårdnad som lindrar lidande och ökar upplevelse av hälsa.

  • Sundbom, Ellen
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Bunjaku, Mirela
    Luleå University of Technology, Department of Health Sciences.
    Omvårdnadsinterventioner för att främja hälsa hos personer som lever med hemodialysbehandling: En integrerad kunskapsöversikt2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Hemodialysis is a treatment that may be needed when the kidneys do not work properly and are unable to clean the blood adequately. This treatment takes a lot of energy from the person undergoing the procedure. Living with hemodialysis treatment is a lifestyle that requires adaptation, both mentally and physically. Hospital visits are a must and the health of the person is greatly affected. The purpose was to compile knowledge of nursing interventions to promote the health of people living with hemodialysis treatment. This will enable nurses to have nursing interventions to work on to promote the health of people living with hemodialysis. The method used was an integrated literature review to capture as many interventions as possible for people with hemodialysis, regardless of qualitative or quantitative studies. Analysis resulted in six themes such as: provide knowledge, to support, to stimulate physical activity, to promote relaxation, to relieve symptoms and to follow up. By using nursing interventions, the health of people living with hemodialysis treatment can be promoted through pedagogical, supportive and relieving actions. The conclusion was that nursing interventions that emerged in the result led to a promoted health. Nursing's relationship with the patient was important and is essential for nursing intervention to be carried out in collaboration with the person living with hemodialysis.

  • Unander, Max
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Autonomous flying  of quadrotor: for 3D modeling and inspection of mineshafts2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis presents a purposed navigation and control solution for autonomous ying of a quadrotor in conned spaces where positioning with GPS is notfeasible. The problem and related application considered is autonomous ying of a quadrotor in mineshafts for 3D modeling and inspection. Theoryand test results are presented including positioning experiments with a cameracombined with a UWB-ranging radio and a P-PI regulator for position control.It is argued that this is a viable and cost eective solution that can be usedto determine the position of the copter and control its position to within 0.2meters with stable controlled velocity.

  • Vikström, Matilda
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Edlund, Desirée
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Byggnadstekniska lösningar för brandskydd på radhusvindar2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • Lukanovic, Matej
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Evaluation Analysis of the UV-detector on the Mini-EUSO Space Telescope2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Extragalactic charged particles, each with energies rising up to and beyond 1 Joule, have been studied for almost a century. Yet, no precise evidence have proven to show where they might originate from as their energy levels rise above the current familiar acceleration sources in outer space. The highly energetic particles have been given the name Ultra-High Energy Cosmic Rays (UHECR) and investigations of particle properties such as primary energy, mass composition and direction can be made through indirect measurements of the interaction between the UHECR and Earth's atmosphere. The considered interaction induces an Extensive Air Shower (EAS) which emits fluorescent light in the Ultraviolet (UV) range. The probability of detecting such events is, however, as low as a few particles per km2 per century. Making observations more sufficient therefore requires larger detection volumes.

    By introducing the Mini-EUSO instrument, a telescope of which the main purpose is to measure the UV-light radiated from the Earth in the wavelength range of 300-400 nm, allows just for this. To be accommodating the International Space Station and targeting Earth in the nadir direction, the Mini-EUSO instrument will allow for a higher exposure to the interactions than what is currently available. The use of two Fresnel lenses provides the instrument with a large field of view (±22o) and the detections are made through multiple photomultiplier tubes.

    The scope of this thesis is to evaluate the main detector of the Mini-EUSO instrument (i.e. the UV-detector) through ground-based tests. The procedures involved in the evaluation have consisted of; validating the statistical distributions of the signals, implementing dark field and flat field calibrations, and radiations measurements with three kinds of radiation sources. The data from the tests were provided during two periods and the visualization was made by adapting an already existing piece of code, using Python and ROOT Cern, to perform step by step procedures such that all operations are overlooked properly.

    The analysis showed that the implementation of the dark field and flat field procedures improved the original image significantly. It also showed that both the lower and higher photon count values in a pixel indeed gave the expected statistical behaviours, with a Poissonian distribution for low values and a Gaussian distribution for higher values. The flat fielding screen did however show unknown fluctuations in the emitted light and further tests have to be implemented to assure its functionality. Under proper covering, almost no dark current was found, however, observation tests showed that the borders of the Multi-Anode Photomultiplier Tubes (MAPMTs) gave higher photon count values than the center part even when they were emitted with Lambertian light.

  • Berezhnoi, Evgeni
    et al.
    Yaroslav State Univerity, Yaroslavl, Russia.
    Maligranda, Lech
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    On the representability of cones of monotone functions in weighted Lebesgue spaces and the extrapolation of operators on these cones2017In: Algebra i Analiz, ISSN 0234-0852 (print), Vol. 29, no 4, p. 1-44Article in journal (Refereed)
    Abstract [en]

    We have proved that boundedness of a sublinear operator on the cone of monotone functions is equivalent to boundedness of the involved operator with it on a new space, which is constructively built. Using this construction we were able to prove a new extrapolation theorems on this cone in weighted Lebesgue spaces.

  • Jóźwik, Izabela
    et al.
    Politechnika Łódzka.
    Maligranda, Lech
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Terepeta, Małgorzata
    Politechnika Łódzka.
    Stefan Kempisty (1892--1940)2017In: Antiquitates Mathematicae, ISSN 2287-0113, E-ISSN 2353-8813, Vol. 11, no 1, p. 61-111Article in journal (Refereed)
    Abstract [en]

    Stefan Jan Kempisty was a Polish mathematician, working in the theory of real functions, set theory, integrals, interval functions and the thory of surface area. In 1919 he defended his Ph.D. thesis ``On semi-continuous functions" at the Jagiellonian University in Krakow under supervision of Kazimierz Zorawski. In December 1924 he did habilitation at the Warsaw University and from 1920 to 1939 he worked at the Stefan Batory University in Vilnius. He published over forty scientific papers, three textbooks and one monograph. He represented in his papers and on seminars the Warsaw school. Kempist's name in mathematics appears in connection with the definition of quasi-continuous functions, different kind of continuity of functions of several variables, the classification of Baire, Young and Sierpinski functions, interval functions and Denjoy and Burkill integrals. We took interest in Kempisty because of his academic achievements, some unexplained personal information, and his 125th birthday in 2017. So we present his biography, participation in conferences, the silhouette his wife Eugenia and daughter Maria, and his scientific achievements. All information about it comes from several sources.

  • Maligranda, Lech
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Piotrowski, Walerian
    Zaklad Epidemiologii i Prewencji Chorob Ukladu Krazenia, Warszawa, Poland.
    Franciszek Włodarski (1889-1944)2017In: Antiquitates Mathematicae, ISSN 2287-0113, E-ISSN 2353-8813, Vol. 11, no 1, p. 3-35Article in journal (Refereed)
    Abstract [en]

    Franciszek W{\l}odarski was a Polish mathematician, working in geometry and topology. In 1911 he defended his Ph.D. thesis {\it Projective geometry of the ball in terms of analytic vector} at the University of Fribourg in Switzerland. He published seven scientific papers, two textbooks and translated in 1917, from Italian into Polish, the book by Federigo Enriques, {\it Lectures on Projective Geometry}. His life and scientific achievements are described. Paper finishes with a full list of his scientific achievements, including his invention patented in the years 1929-1930 in four countries.

  • Maligranda, Lech
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Prytula, Jaroslaw
    Ivan Franko National University of Lvov, Ukraine.
    Uniwersytet we Lwowie w latach 1939-1941: Matematyka, fizyka i astronomia2017In: Wiadomosci Matematyczne, ISSN 2080-5519, Vol. 53, no 2, p. 303-329Article in journal (Refereed)
    Abstract [en]

    History of the Lvov University and the Faculty of Physics and Mathematics in the period 1939--1941 is presented. University of Lvov in this period changed the name three times. In the period from 8 November 1919 until October 1939 it was the University of Jan Kazimierz that from 1 December 1939 to January 1940 to wear the name of Lvov State University SSSR. However, already in January 1940, he took the name of Lvov State University of Ivan Franko and with this name functioned until August 1941, when it was closed by the Germans.We describe the details concerning the Department of Physics and Mathematics in the period. Everything has beendescribed on the basis of available documents or the description of other people, witnesses events of this period.

  • Blanco, Ana Maria
    et al.
    Institute for Electrical Power Systems and High Voltage Engineering, Technische Universität Dresden.
    Gupta, Manish
    Malaviya National Institute of Technology, Jaipur .
    Gil de Castro, Aurora
    Departamento de Arquitectura de Computadores, El ectrónica y Tecnología Electrónica, Universidad de Córdoba.
    Rönnberg, Sarah
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Meyer, Jan
    Institute for Electrical Power Systems and High Voltage Engineering, Technische Universität Dresden.
    Impact of flat-top voltage waveform distortion on harmonic current emission and summation of electronic household appliances2018In: Renewable Energy and Power Quality Journal, ISSN 2172-038X, Vol. 1, no 16, p. 698-703, article id 437Article in journal (Refereed)
    Abstract [en]

    Electronic household appliances are non-linearloads and emit harmonics into the low voltage networks.Usually, these loads are simply modelled by constantcurrent source models, which only represent the harmonicemission of the appliances for a single supply voltagedistortion, mostly sinusoidal conditions.Measurements have shown that the harmonic currentsemitted by electronic devices can significantly depend onthe circuit topology and the existing supply voltagedistortion. This paper studies the impact of supply voltagedistortion, which can be typically found in public lowvoltage networks (so-called flat-top voltage waveform), onthe harmonic current emission of individual devices withdifferent circuit topologies as well as the impact of supplyvoltage distortion on the harmonic summation of thesedevices.

  • Darwesh, Ali K.
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Rasmussen, Thorkild Maack
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Wiper Trips Effect on Wellbore Instability Using Net Rising Velocity Methods2018In: Open Petroleum Engineering Journal, ISSN 1874-8341, Vol. 11, p. 14-28Article in journal (Refereed)
    Abstract [en]

    Background: This paper discusses the wiper trip effects on well instability in shale formations.Objectives: Problematic shale interval sections have been studied for the time spent on the wiper trip operations. Lifting efficiency and well wall instability change with the time analyzed. Detailed drilling operation, formation heterogeneity, rheological and filtration characteristics of polymer water-based mud are discussed. Physical and chemical properties of the drilled formation and drilling fluid are also studied.Materials and Methods: Wiper trips are analyzed using a typical drawing program to find the relations between the most controllable parameters. For that, two calculation models have been implemented to find the net rising cutting particles velocity in the annular. The relation between the net rising velocity and wiper trips is analyzed. Laboratory works have been done to support the findings of field work.Results: Strong relations have been found between the wiper trip impacts and lithology types of the penetrated shale.Conclusion: A modified drilling program is proposed in relation to changes in casing setting depth and drilling fluid properties that make the operations more efficient in cost and time.

  • Hoseinie, Seyed Hadi
    et al.
    Department of Mining Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran.
    Al-Chalabi, Hussan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Ghodrati, Behzad
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Comparison between Simulation and Analytical Methods in Reliability Data Analysis: A Case Study on Face Drilling Rigs2018In: Data, ISSN 2306-5729, Vol. 3, no 2, article id 12Article in journal (Refereed)
    Abstract [en]

    Collecting the failure data and reliability analysis in an underground mining operation is challenging due to the harsh environment and high level of production pressure. Therefore, achieving an accurate, fast, and applicable analysis in a fleet of underground equipment is usually difficult and time consuming. This paper aims to discuss the main reliability analysis challenges in mining machinery by comparing three main approaches: two analytical methods (white-box and black-box modeling), and a simulation approach. For this purpose, the maintenance data from a fleet of face drilling rigs in a Swedish underground metal mine were extracted by the MAXIMO system over a period of two years and were applied for analysis. The investigations reveal that the performance of these approaches in ranking and the reliability of the studies of the machines is different. However, all mentioned methods provide similar outputs but, in general, the simulation estimates the reliability of the studied machines at a higher level. The simulation and white-box method sometimes provide exactly the same results, which are caused by their similar structure of analysis. On average, 9% of the data are missed in the white-box analysis due to a lack of sufficient data in some of the subsystems of the studies’ rigs.

  • Knutsson, Roger
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Viklander, Peter
    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.
    Laue, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Geothermal study to explain man-made permafrost in tailings with raised surface2018In: Environmental Earth Sciences, ISSN 1866-6280, E-ISSN 1866-6299, Vol. 77, no 7, article id 288Article in journal (Refereed)
    Abstract [en]

    Deposition of mine tailings in a cold climate requires precautions as temporary sub-zero temperatures can imply considerable consequences to the storage due to creation of permafrost. The risk of creating man-made permafrost lenses due to tailings deposition exists even in regions with no natural permafrost, as material being frozen during winter might not fully thaw by the following summer. When such frozen layers thaw during later longer warmer periods, excess pore water pressure and large settlements might develop. Such implications close to the dam structure have to be avoided and therefore the risk of generating permafrost should be reduced. This paper describes a geothermal model for one-dimensional heat conduction analysis. The model is able to simulate the temperature profile in tailings where the surface elevation is constantly increased due to deposition. At the tailings surface, the boundary condition is the air temperature changing over time during the year. Air temperatures, tailings deposition schedule and tailings properties are given as input to the model and can easily be changed and applied to specific facilities. The model can be used for tailings facilities in cold regions, where the effects of tailings deposition on the temperature regime are of interest. Findings can improve tailings management by explaining man-made permafrost generation. The model can also aid in setting up appropriate deposition schedules and to prevent generation of permafrost layers.

  • Sissakian, Varoujan K.
    et al.
    aculty of Geology, University of Kurdistan, Erbil .
    Abdul Ahad, Ayda
    Iraq Geological Survey, Baghdad.
    Al-Ansari, Nadhir
    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.
    Neotectonic Activity from the Upper Reaches of the Arabian Gulf and Possibilities of New Oil Fields12018In: Geotectonics, ISSN 0016-8521, E-ISSN 1556-1976, Vol. 52, no 2, p. 240-250Article in journal (Refereed)
    Abstract [en]

    Upper reaches of the Arabian Gulf consist of different types of fine sediments including the vast Mes-opotamia Plain sediments, tidal f lat sediments and estuarine sabkha sediments. The height of the plain startsfrom zero meter and increases northwards to three meters with extremely gentle gradient. The vast plain to thenorth of the Arabian Gulf is drained by Shat Al-Arab (Shat means river in Iraqi slang language) and KhorAl-Zubair (Khor means estuary). The former drains the extreme eastern part of the plain; whereas, the latterdrains the western part. Shat Al-Arab is the resultant of conf luence of the Tigris and Euphrates rivers nearAl-Qurna town; about 160 km north of the Arabian Gulf mouth at Al-Fao town; whereas, the length of KhorAl-Zubair is about 50 km; as measured from Um Qasir Harbor. The drainage system around Khor Al-Zubair isextremely fine dendritic; whereas around Shat Al-Arab is almost parallel running from both sides of the rivertowards the river; almost perpendicularly. The fine dendritic drainage around Khor Al-Zubair shows clearrecent erosional activity, beside water divides, abandoned irrigation channels and dislocated irrigational chan-nels and estuarine distributaries; all are good indication for a Neotectonic activity in the region. These may indi-cate the presence of subsurface anticlines, which may represent oil fields; since tens of subsurface anticlinesoccur in near surroundings, which are oil fields.

  • Kejonen, Alexander
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Gränslöst arbete: En kvalitativ studie2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis has been designed to investigate how the boundaryless work is expressed among managers of City building department in Lulea county. The purpose of the study has therefore been communicated with the following research questions; 1) How does the boundaryless work among managers at various levels of the City building department express itself? 2) In which ways have the managers been affected by the boundaryless work? What consequences has it resulted in? 3) What actions can the departments HR function apply by improving or developing the managers' work situation in relationship to the boundaryless work? The study has had a qualitative approach in which fifteen semi structured interviews have been the basis for the study’s result. The theoretical framework of the study has consisted theories on boundaryless work by Allvin et al. (1998; 2006). The theoretical framework has also been supplemented with Karasek and Theorell's (1990) three-factor model to gain a deeper understanding of the interviewees' work situation. The study's results have shown that the boundaryless work expresses itself through a high degree of flexibility and workload. Both positive and negative consequences of the boundaryless work have emerged among the managers. Within the discussion section, it is argued that the City building department needs to apply several efforts to reduce the negative effects of boundaryless work. The argument has resulted in proposals to reduce the number of physical meetings, increase the skills development of new managers, encourage and communicate to managers that they need to be off duty on their spare time, create more private working hours among managers and finally ensure an increasing level of support from the supporting functions (HR, etc.) among managers.

  • Nilsson, Markus
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Optimering av käftkross för Kankbergsmalm2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Kankberg’s gold and tellurium ore has been shown to consist of more easily-ground ore and more hard-ground ore for the last decade. When the hard-ground ore enters the enrichment-plant so can the flow rate of the autogenous mill almost halved, from 110 ton/hour (easily-ground ore) compared to 60 ton/hour (hard-ground ore). What one wishes to try to achieve is to identify the ore-type and affect the conversion of the crushing process into the jaw-crusher of the hard-ground ore, so that you can finally get as equally tonnes per unit of time in the autogenous mill as can be obtained from easily-grounded ore. By optimizing the jaw-crusher, it will lead to a reduced total energy consumption in the autogenous mill, resulting in high product quality and reduced production costs. A number of surveys and tests were done when the jaw-crusher was active in order to identify what kind of oret hat has been going through the jaw-crusher. The aim was to get as so-called ”key indicator” that has the unit kWh/ton, which could then be used to identify the ore type. As a result, it was possible to distinguish the type of ore that was more hard-ground ore and easily-ground ore by comparing different values of the ”key indicators” with equal mass of tonnes ore and varied energy consumption. Based on these results, it is possible to streamline the turnover of the autogenous mill at the enrichment plant, thanks to an efficient system of the jaw-crusher.    

  • Caspár, Sophia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Visualization of tabular data on mobile devices2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis evaluates various ways of displaying tabular data on mobile devices using different responsive table solutions. It also presents a tool to help web developers and designers in the process of choosing and implementing a suitable table approach. The proposed solution for this thesis is a web system called The Visualizing Wizard that allows the user to answer some questions about the intended table and then get a recommended responsive table solution generated based on the answers. The system uses a rule-based approach via Prolog to match the answers to a set of rules and provide an appropriate result. In order to determine which table solutions are more appropriate to use for which type of data a statistical analysis and user tests were performed. The statistical analysis contains an investigation to identify the most common table approaches and data types used on various websites. The result indicates that solutions such as "squish", "collapse by rows", "click" and "scroll" are most common. The most common table categories are product comparison, product offerings, sports and stock market/statistics. This information was used to implement and establish user tests to collect feedback and opinions. The data and statistics gathered from the user tests were mapped into sets of rules to answer the question of which responsive table solution is more appropriate to use for which type of data. This serves as the foundation for The Visualizing Wizard.

  • Johansson, Jeaneth
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Malmström, Malin
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Wincent, Joakim
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design. Hanken School of Economics.
    Pre-Designated Potential: Golden Eggs and Invisible Shadows2017In: The European Financial Review, ISSN 1757-5680, no Dec-Jan, p. 6-8Article in journal (Other (popular science, discussion, etc.))
  • Lundin, Frida
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Skjuvhållfasthetsbestämning i kohesionsjord: en del av ett utvecklingsprojekt för en ny vingförsöksutrustning2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The report is part of the development project run by Ingenjörsfirman Geotech AB, where some of the field investigations were carried out in collaboration with Bohusgeo AB. The aim of the thesis is to do field investigations with the new Vane Geotech Nova (Nova-vane) equipment, and compare the results with known and proven methods.

    The vane test is an in situ method that determines the undrained shear strength, for example for clay soils. Eight tests have been performed with the Nova-vane and they have been compared with the Nilcon-vane, an electronic Nilcon-vane, a CPT-probing and Direct shear tests in the laboratory. Parameter determination has been done with CRS-tests and ordinary laboratory routine examination.

    According to earlier research, the time for failure, waiting time and rotational speed are parameters that have been tested in order to know how they affect the evaluated shear strength in clay soils. Previous investigations from 1950 to 1990 show that the parameters mentioned above have a major impact on the evaluated shear strength.

    When comparing already known evaluation methods for the undrained shear strength, it has been found that the Nova-vane generates shear strength measurements are far too low. The reason why the Nova-vane shows lower undrained shear strengths than other methods may be due to a number of factors. The analysis of the tests shows that the rotation speed has not been constant, as the rotation is becoming faster and faster, the time to failure varies between a few seconds to several minutes over the recommended time to failure. Another major factor is the deviating angle compared to the vertical plane, the vane has been driven down with.

    In the eight tests, the rotational speed has been a difficult parameter to control. The electric engine used, a modified Geotech EVT 2000 electric vane instrument, could only apply different energies and are normally used for 22 mm probe rods. Which specific applied force on the rods generating the correct rotational speed, depends entirely on the properties of the clay. When 36 mm probe rods are used together with the electric engine the rotational speed is even more difficult to control.

    According to the SGF recommended standard from 1993 states that the time to failure of a vane test should be between 2 and 4 minutes, from the time the vane is activated. It primarily depends on the speed of rotation, which means that the time for failure was also a difficult parameter to control.

    The angle with which the Nova-vane is driven increases with depth to about 30° at 30 meters. While the angle of CPT-probing increases only 5° at 30 meters. The driven angle could have significance to the shear strength, although it is difficult to conclude what kind. The Nova-vane is the only vane borer that can measure which angle it is driven down with. The increasing angle is assumed to depend on the geometry of the instrument and not on the properties of the clay.

    The conclusion is that the measurement with the Nova-vane gives lower values than the other methods. However, the range of values proves only small differences down to the depth of 20 meters. The system as a whole is working with an acceptable accuracy, although a stronger engine and a more precise control of the engine speed is needed. More tests have to be done to determine how the Nova-system can be designed and how the investigation should be performed to get equal values as other proven methods. 

  • Carlsson, Elin
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Sörebö, Victoria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Utveckling av konventionella småhus till passivhus: En studie med analys av livscykelkostnader, förändring av boendekvaliteter och ett förslag till en alternativ utformning2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The climate changes increases as the population increases. The negative environmental impact is mostly based on the use of raw materials and energy consumption in the production of various products. According to Energimyndigheten (2015), the building sector is the cause of about 40 % of Sweden's total energy use. In order to reduce the energy use goals have been created at both national and international levels. The goals are intended to create a greater understanding of a more energy efficient society for all actors within the construction industry. In addition to create a sustainable development of the building sector one needs to also take in account the social and economic aspects.

     

    This master thesis examined whether two specific standard houses from a small house producer can be adapted to passive houses with a preserved architectural character. The purpose of the study is partly to investigate whether the concept of passive houses can serve as a sustainable concept of building single family houses. The concept of sustainable development has been simplified. The ecological aspect is represented by the energy calculations and possible actions that the standard houses need to achieve in order to meet the requirements for passive houses. The economic aspect is represented by a life cycle cost analysis using the Net Present Value method and the Simple Payback method. The social aspect is represented by an evaluation of changes in living qualities as the standard houses develops to passive houses. The study also presents an alternative design of a passive house with the purpose of improving the accommodation qualities.

     

    The standard houses belong to a small-house-producer, Intressanta hus, who has their main market in Västerås. The houses is represented by a 147m2 villa with one floor and a pulpit roof and a 151m2 villa with two floors and a pitched roof. Due to Intressanta hus geographic location, the typical climate for Västerås has been used in the energy calculations. To add another dimension, opportunities for developing the standard houses to passive houses have also been investigated for the typical climate in Kiruna. Therefore Västerås represents climate zone III and Kiruna represents climate zone I.

     

    The results revealed that it is possible to adapt the standard house with two floors and a pitched roof to a passive house while preserving the architectural character in both climate zones. The standard house with one floor and a pulpit roof is only possible to adjust to a passive house in climate zone III with a preserved architectural character. The life cycle cost analysis using the Net Present Value showed that it is an economical advantage to invest in a passive house in a period of 50 years. The accommodation quality that changes the most is the incident light in the houses and for the passive house with one floor the difference of light is remarkably high in climate zone I.

  • Björkvall, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Studie om dynamiken i en pilotrullkrets med rulltrumma2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Luossavaara-Kiirunavaara AB (LKAB) produce pellets from magnetite iron ore. Pellets are formed by balling moist iron ore concentrate to green pellets, which are then burned to pellets. The green pellets are formed in balling circuits consisting of balling drums and roller decks for screening. In 2017 a pilot scale balling circuit with a drum was completed in LKAB's agglomeration laboratory in Malmberget. The purpose of the pilot balling circuit is to predict the dynamics in a full scale balling circuit under different conditions.

    This master degree project is an initial attempt to study the response in LKAB's pilot circuit in terms of green pellet quality and dynamics in the circuit. The goal was to determine an effective way to run experiments and to investigate whether the pilot circuit can predict the dynamics of balling in large-scale circuits. Pelletizing production is within LKAB's core competence, and therefore the origin and character of the reagents, as well as the design of the pilot balling drum circuit, are confidential. Code names are used for both iron ore concentrates and reagents.

    The work began by creating a test procedure with the aim of running as many different mixtures as possible in the pilot balling circuit during a normal working day. Five different mixtures could be run. Four different additives were tested: bentonite, a flotation reagent (FLOT), an organic binder (OB) and a new development product (UTV). The first experiment in the pilot balling circuit was run with varying doses of bentonite because its impact in balling is well known at LKAB. Experiment two and three, with FLOT and OB, could be compared to previous experience from large scale test runs. The fourth and last experiment was a test of how the pilot circuit predicted the behavior of a new development product UTV. Each type of experiment was performed twice.

    The pilot balling circle predicted well both dynamics and green pellet quality in all three experiments where experience from large-scale runs was available. The new, unknown, UTV product showed improved green pellet quality, without affecting adversely on the dynamics of the circuit. UTV can therefore be an interesting option for a future large scale run at LKAB.

    The developed working schedule worked very well. A "basic analysis package" has been created to facilitate planning of future experiments in the pilot balling circuit. The number of persons needed to run the circuit depends on the number of mixtures and analyzes. For smaller experiments, at least five people is required, in addition to the leader of the experiments. More advanced experiments will demand seven people.

  • Bertholdsson, Morgan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Utredning om dimension av kamjärnsbultar i Garpenbergsgruvan2018Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
  • Didenko, Artem
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Omhändertagande av barn och ungdomar: Socialtjänstens roll i frågan om ungdomar med svåra livssituationer2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • Public defence: 2018-05-07 09:00 E632, Luleå
    Alhashimi, Anas
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Statistical Sensor Calibration Algorithms2018Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The use of sensors is ubiquitous in our IT-based society; smartphones, consumer electronics, wearable devices, healthcare systems, industries, and autonomous cars, to name but a few, rely on quantitative measurements for their operations. Measurements require sensors, but sensor readings are corrupted not only by noise but also, in almost all cases, by deviations resulting from the fact that the characteristics of the sensors typically deviate from their ideal characteristics.

    This thesis presents a set of methodologies to solve the problem of calibrating sensors with statistical estimation algorithms. The methods generally start with an initial statistical sensor modeling phase in which the main objective is to propose meaningful models that are capable of simultaneously explaining recorded evidence and the physical principle for the operation of the sensor. The proposed calibration methods then typically use training datasets to find point estimates of the parameters of these models and to select their structure (particularlyin terms of the model order) using suitable criteria borrowed from the system identification literature. Subsequently, the proposed methods suggest how to process the newly arriving measurements through opportune filtering algorithms that leverage the previously learned models to improve the accuracy and/or precision of the sensor readings.

    This thesis thus presents a set of statistical sensor models and their corresponding model learning strategies, and it specifically discusses two cases: the first case is when we have a complete training dataset (where “complete” refers to having some ground-truth informationin the training set); the second case is where the training set should be considered incomplete (i.e., not containing information that should be considered ground truth, which implies requiring other sources of information to be used for the calibration process). In doing so, we consider a set of statistical models consisting of both the case where the variance of the measurement error is fixed (i.e., homoskedastic models) and the case where the variance changes with the measured quantity (i.e., heteroskedastic models). We further analyzethe possibility of learning the models using closed-form expressions (for example, when statistically meaningful, Maximum Likelihood (ML) and Weighted Least Squares (WLS) estimation schemes) and the possibility of using numerical techniques such as Expectation Maximization (EM) or Markov chain Monte Carlo (MCMC) methods (when closed-form solutions are not available or problematic from an implementation perspective). We finally discuss the problem formulation using classical (frequentist) and Bayesian frameworks, and we present several field examples where the proposed calibration techniques are applied on sensors typically used in robotics applications (specifically, triangulation Light Detection and Rangings (Lidars) and Time of Flight (ToF) Lidars).

  • Nilimaa, Jonny
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Hösthagen, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering. anders.hosthagen@ltu.se.
    Emborg, Mats
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Validation of the Swedish Crack Risk Estimation Models2017In: Proceedings of the 23rd Nordic Concrete Research Symposium: Aalborg, Denmark, 21 - 23 August 2017, Oslo: Nordic Concrete Federation , 2017, p. 321-324Conference paper (Refereed)
    Abstract [en]

    Thermal cracking may occur during the early hardening process of concrete as a result of the exothermic reactions between water and cement. An approach for thermal crack risk estimation and prevention was introduced in the Swedish design guidelines BRO 94. This paper studies and validates the current safety levels existing concrete structures. Three slab-frame structures were analysed and the preliminary crack risk estimations were compared to the actual cracking and post-estimations were carried out, using actual parameters. This paper shows that all the studied walls with a strain ratio over 70% were affected by thermal cracks.

  • Kumar, T K Sandeep
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    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.
    Björkman, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Dahlin, Anders
    LKAB.
    Nurni, Viswanathan
    Indian Institute of Technology Bombay .
    Investigating the Oxidation Phenomena of Magnetite Pellet2017Conference paper (Refereed)
    Abstract [en]

    Induration of magnetite pellet is a complex physico-chemical process involving oxidation, sintering and the heat transfer phenomena. Often, these phenomena happen simultaneously and influence each other in the induration furnace. It could be because of the highly exothermic nature of oxidation phenomena that can result in significant temperature gradients inside the pellet and sintering might begin much earlier that it is ideally supposed to. This could results in the formation of pellets with heterogeneous phases and crystallographic properties such as duplex structure, and results in the inferior quality of pellets across the bed. In order to predict the optimum thermal profile to achieve homogenous good quality pellets on consistent basis, it is necessary develop a model based on the kinetics of each of these phenomena. This will help to identify and optimize the responsible process parameters during induration accordingly. Subsequent to the investigation of sintering kinetics of magnetite pellets, the current study focuses on the oxidation phenomena. The reaction mechanisms for oxidation of magnetite pellets is dependent primarily on factors such as temperature and oxygen content in the oxidizing gas, etc. Isothermal oxidation of magnetite at pellet scale has been studied experimentally using Thermogravimetric Analyzer (TGA) by inserting the single pellet directly into the isothermal zone of the furnace. It has been found that the oxidation phenomena in the magnetite pellets is a multi-stage phenomena dominated by distinct mechanisms depending on varying extent of oxidation with respect to temperature and oxygen content.

  • Fischer, Robert
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Elfgren, Erik
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Toffolo, Andrea
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Energy Supply Potentials in the Northern Counties of Finland, Norway and Sweden towards Sustainable Nordic Electricity and Heating Sectors: A Review2018In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 11, no 4, article id 751Article in journal (Refereed)
    Abstract [en]

    The lands in the northernmost corner of Europe present contradictory aspects in their social and economic development. Urban settlements are relatively few and small-sized, but rich natural resources (minerals, forests, rivers) attract energy-intensive industries. Energy demand is increasing as a result of new investments in mining and industries, while reliable energy supply is threatened by the planned phase out of Swedish nuclear power, the growth of intermittent power supplies and the need to reduce fossil fuel consumption, especially in the Finnish and Norwegian energy sectors. Given these challenges, this paper investigates the potentials of so far unexploited energy resources in the northern counties of Finland, Norway and Sweden by comparing and critically analyzing data from statistic databases, governmental reports, official websites, research projects and academic publications. The criteria for the technical and economic definition of potentials are discussed separately for each resource. It is concluded that, despite the factors that reduce the theoretical potentials, significant sustainable techno-economic potentials exist for most of the resources, providing important insights about the possible strategies to contribute to a positive socio-economic development in the considered regions.

  • Malmström, Malin
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Voitkane, Aija
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Johansson, Jeaneth
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Wincent, Joakim
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design. Hanken School of Econom.
    VC Stereotypes About Men and Women Aren’t Supported by Performance Data2018In: Harvard Business Review, ISSN 0017-8012, Vol. March 15Article in journal (Refereed)
  • Bao, Jiangdong
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human and technology. Centre of Advanced Mining and Metallurgy, CAMM.
    Johansson, Jan
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human and technology. Centre of Advanced Mining and Metallurgy, CAMM.
    Zhang, Jingdong
    Research Center for Environment and Health, Zhongnan University of Economics and Law.
    Evaluation on Safety Investments of Mining Occupational Health and Safety Management System Based on Grey Relational Analysis2018In: Journal of Clean Energy Technologies, ISSN 1793-821X, Vol. 6, no 1, p. 1-5Article in journal (Refereed)
    Abstract [en]

    In order to effectively evaluate the relationship between safety investments and accident impact losses in the mining occupational health and safety management system, a grey relational analysis model is established. Firstly, 4 firstgrade indicators including safety technical measures fee etc. and 23 second- grade ones including ventilation system etc. are established. Secondly, by calculating the grey relational analysis between the variables of the data sequence and the system characteristic variables, analysis results of advantages and the evaluation ones are obtained. Finally, the model is validated by case study. The results demonstrate that the investments of safety technical measures and safety management and training have a great impact on the accident losses. The quantitative analysis of safety investments and losses is realized by the model, which provides the direction for the enterprise's strategic investments and reduces the economic losses.

  • Bao, Jiangdong
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human and technology.
    Johansson, Jan
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human and technology.
    Zhang, Jingdong
    Zhongnan University of Economics and Law, Wuhan, China.
    Evaluation on Safety Benefits of Mining Industry Occupational Health and Safety Management System Based on DEA Model and Grey Relational Analysis2018In: International Journal of Engineering and Technology, ISSN 0975-4024, Vol. 10, no 117193111191, p. 82-88Article in journal (Refereed)
    Abstract [en]

    The mining industry safety production situation is becoming more and more severe in China with safety accidents occurring frequently, which is closely related to insufficient safety investments and unreasonable distribution. Additionally, it does not keep in line with the main purpose of occupation health and safety management system (OHSAS18001).In order to carry on the reasonable scientific disposition to the safety investments of the mining industry, increase safety investments efficiency and satisfy the requirements of OHSAS18001, data envelopment analysis (DEA) is adopted to calculate the safety investments, loss and output. Firstly, the analysis software MYDEA of DEA is used to calculate the results to obtain the evaluation result of safety benefits. Secondly, the target value of the improvement work in the aspect of investment is achieved by method of projection analysis when the decision making unit (DMUj0) of non DEA efficiency is changed into DEA efficiency. Lastly, it can be obtained on the basis of grey relational analysis (GM) that the investment amount of safety management and training of employees has the highest relation on the effective safety benefits of the mining industry. Thus, the investment of safety management and training of employees should be strengthened. This kind of empirical method of comprehensive model provides a direction and theoretical reference for safety investments benefits analysis and optimized investment structure, and a structure for the effective operation of mining industry occupational health and safety management system

  • Joffe, Roberts
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Swerea SICOMP.
    Forsberg, Fredrik
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Lycksam, Henrik
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Sjögren, Anders
    Lund University.
    Characterization of defects in polymer composites used in medical devices by means of x-ray microtomography2017In: 3rd International Conference on Tomography of Materials and Structures (ICTMS2017), 2017Conference paper (Refereed)
    Abstract [en]

    This paper presents a study on micro-structural characterization of carbon fibre-reinforced plastics used inmedical devices. The focus of the investigation is on determination of void content in the materials, since voids act asdefects and will affect the service life of the composites/devices. The results show that x-ray microtomography is anaccurate and powerful technique to identify defects in composites, and it is of great value in quality control.

  • Joffe, Roberts
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Pupure, Liva
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Berthold, Fredrik
    Innventia AB.
    Varna, Janis
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Micro-structure and Mechanical Properties in PLA Reinforced with Cellulosic Fiber Sheets Made by Wet Forming Method2017In: 8th International Conference on Composites Testing and Model Identification: CompTest2017 / [ed] S.V . Lomov, L. Gorbatikh, Y. Swolfs, 2017Conference paper (Refereed)
    Abstract [en]

    The current paper presents results of study of composites produced by compression moulding of sheets of comingled PLA and reinforcing fibers. The dynamic sheet former is employed to produce fiber mats (with the PLA in the form of fibers) which are consolidated into composite plates by using hot press. This processing route ensures that initial length of the fibers is preserved during the manufacturing and preferential fiber orientation is achieved. However, the internal structure of the composites in question is very complex and somewhat unpredictable, which complicates design of these materials. The main objectives of this paper are application and validation of micro-mechanical models on composites produced within this study as well as direct (experimental) and indirect (back-calculation) identification of input parameters to be used in the modelling. The main input parameters considered in this study are fiber orientation and porosity. The estimation of these parameters is done through micro–computed tomography but also by using micro-mechanical expressions in combination with experimental results (e.g. composite density, stiffness). The input parameters identified by different approaches are compared, then these parameters are used in the micro-mechanical models to predict stiffness of composites with different types of fibers and various fiber contents.

  • Wiberg Steen, Tobias
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Genetic relationships and origin of the Ädelfors gold deposits in Southeastern Sweden2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Ädelfors is situated ca 17 km east of Vetlanda, Jönköping County, in the N-S striking Trans-scandinavian igneous belt and is a part of the NE-SW striking 1.83-1.82 Ga Oskarshamn-Jönköping belt emplaced during a continental subduction towards the Svecofennian continental margin. The continental arc hosts the 1.83 Ga metasedimentary Vetlanda supergroup composed of foliated metagreywacke, metasandstone and metaconglomerate. The sequence is intercalated by mafic and felsic volcanites and hosts the Cu-Au-Fe-mines at Ädelfors.

    Ädelfors mining field consists of ca 330 mineralized quartz veins hosting both copper, gold and iron. The iron mines Nilsson’s iron mine (NFE) and Fe-mine (FE), the copper mine Kamelen (KM) and the gold mines Brånad’s mine (BR), Adolf Fredrik’s mine (AF), Old Kron mine (GKR), Old Kolhag’s mine (GKO), Thörn mine (TH), New Galon mine (NG), Stenborg’s mine (ST), Tysk mine (TG), Hällaskallen (HS) and Fridhem (FR) have been investigated to deduce a possible genetic relation between the veins and their origin. Sulfur isotope ratios have also been conducted on pyrite from KM, AF and FE.

    The veins can stucturally be divided into several groups. AF, GKR, ST, NG, TH and possibly NFE are striking 10-70° with a dip of 55-70°. BR, GKO and KM are striking 110-140° with a dip of 80-90° whereas TG and HS strike 90-110° dipping 85°. Fridhem, being distal to the other mines, strikes 70° and dips 80°. A chlorite-quartz-biotite-sericite-rich metapelite hosts the veins in all localities except; FR where a layered, beresitizised felsic volcanite rich in plagioclase, sericite, biotite and quartz hosts disseminated pyrite; and NFE, HS and NG which are hosted by a mafic tuffite. Quartz veins are mainly milky and equigranular, exceptions are FE with black pyrite-bearing quartz veins, cutting through the banded magnetite-metapelite and KM with its dynamically recrystallized quartz. Chlorite-, zeolite-, carbonate-, hematite-, amphibole-, kalifeldspar-, sericite-, biotite- and epidote alteration has been observed among the localities.

    The ore minerals are dominated by: fractured sub- to euhedral pyrite in cataclastic aggregates or selvage bands, interstitial chalcopyrite in pyrite, marcasite, pyrrhotite, gold and sporadic chalcopyrite diseased sphalerite and arsenopyrite. Previously not reported tetradymite, staurolite, galena and Ce-monazite have also been observed. Bismuthinite and tetradymite as inclusions in pyrite were observed in AF, GKR, FR and TG. Gold was observed in AF, BR, GKR and TG as inclusions in pyrite or quartz with a Au/Ag median of 78.41. HS distinguishes itself with Au/Ag ratios of 4.66-5.25.

    The trace element ratios in pyrite reveal two major types of pyrite. 1) found in FE and KM (pyrite type 1) with Co/Ni ratio of 10.94, Bi/Au of 1.79, Bi/S of 0.037, Au/Ag of 11.13, S/Se of 235.96 and As/S of 0.006. 2) found in NG, GKO, ST, TH, AF, NFE, HS, GKR, BR, FR, TG and as stringers in KM4 py1 pyrite type 2) with an average Co/Ni ratio of 5.26, Bi/Au of 1.95, Bi/S of 0.031, Au/Ag of 4.19, S/Se of 0 and As/S of 0. δ34S values strengthens this grouping as KM and FE has 1,3-2,6 ‰ and AF 3,6-3,8 ‰.

    The following geological interpretation has been concluded: The banded iron formation in FE is the earliest mineralization and was later fractured, emplacing quartz veins with pyrite of type 1. During this event, the Cu-vein in KM was also formed. A second generation of fractures, emplaced after the Småland granitoids formed, were filled with quartz and pyrite of type 2 at mesozonal depth. This is the main stage of gold mineralization and includes NG, GKO, ST, TH, AF, NFE, GKR, BR, FR and TG. During this event, pyrite of type 2 was added to KM, causing recrystallizing of the quartz. HS is possibly emplaced last or altered as it is more enriched in silver. Morphology, mineralogy, alterations, mineral chemistry and sulfur isotope signatures indicates an orogenic origin of the gold-rich quartz veins at Ädelfors as well as the copper-rich vein in KM.

  • Karlsson, Sara
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Implementering av VDC: En studie utförd på Veidekke Entreprenad AB2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A lot of companies are investing in new working methods and technical innovations that is

    developed to improve productivity in the construction industry and to make it more efficient.

    One of these innovations is a working method called VDC,

    Virtual Design and Construction.

    A project called Sörredsmotet is a design-build project with Veidekke Entreprenad AB as a

    design-build contractor. The client of the project is Trafikverket. One of the ambitions with the

    project is to use VDC in the design phase of the project.

    The purpose with this study is to in cooperation with Veidekke examine how the working

    method is implemented on the project, what conditions are needed to implement VDC and also

    how VDC affects designers. The research questions are:

    I. How has the working method VDC been implemented on the project Sörredsmotet?

    II. What conditions are needed to implement VDC?

    III. How does the working method affect designers?

    To answer the research questions three studies have been carried out; a literature study based

    on earlier research, observations of design meeting and VDC-network meetings and an

    interview study with 18 respondents. One demarcation for the study is to examine the VDC in

    design phase only.

    Conclusion for the first research question is that the project works partially with VDC, but the

    working method cannot be considered as implemented on the project. One ambition was to

    carry out the design phase with ICE-sessions, but organization and working method for external

    organization made it difficult to gather the right people and to make decisions on meetings. The

    layout was changed to have design meetings inspired by ICE methodology instead of ICEsessions.

    Part of the design is made in a cloud based 3D-model while other parts of the design

    is made in 2D. Veidekke has developed a visualization model for the project.

    It requires both organizational conditions and conditions for individuals to start using the

    working method. Due to the construction industry’s project

    -based structure many so-called

    innovators and early appliers are requ

    ired. It is necessary to look at the project’s prerequisites

    and to make plans

    about the project’s goals, how to achieve the goals, what is needed to achieve

    them and to make the reason for the change clear. To get as good prerequisites as possible, both

    for internal and possible external organization, this should be done at an early stage of the

    projects. Motivation is also important for implementation of the working method. New skills

    that may be required are mainly concerning models.

    For designers the working method means that the workflow changes when work is done with

    BIM,

    Building Information Model, which is a tool in VDC. More planning and communication

    is required when working with BIM. To work model-oriented instead of working with 2Ddrawings

    requires different ways to think. There are a lot of challenges working with BIM, but

    also many advantages, mainly in projects that requires a lot of coordination.

  • Trubetskaya, Anna
    et al.
    hermochemical Energy Conversion Laboratory, Umeå University.
    Hofmann Larsen, Flemming
    Department of Food Science, University of Copenhagen.
    Shchukarev, Andrey
    Department of Chemistry, Umeå University.
    Ståhl, Kenny
    Department of Chemistry, Technical University of Denmark.
    Umeki, Kentaro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Potassium and soot interaction in fast biomass pyrolysis at high temperatures2018In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 225, p. 89-94Article in journal (Refereed)
    Abstract [en]

    his study aims to investigate the interaction between potassium and carbonaceous matrix of soot produced from wood and herbaceous biomass pyrolysis at high heating rates at 1250°C in a drop tube reactor. The influence of soot carbon chemistry and potassium content in the original biomass on the CO2 reactivity was studied by thermogravimetric analysis. The XPS results showed that potassium incorporation with oxygen-containing surface groups in the soot matrix did not occur during high temperature pyrolysis. The potassium was mostly found as water-soluble salts such as KCl, KOH, KHCO3 and K2CO3 in herbaceous biomass soot. The low ash-containing pinewood soot was less reactive than the potassium rich herbaceous biomass soot, indicating a dominating role of potassium on the soot reactivity. However, the catalytic effect of potassium on the reactivity remained the same after a certain potassium amount was incorporated in the soot matrix during pyrolysis. Raman spectroscopy results showed that the carbon chemistry of biomass soot also affected the CO2 reactivity. The less reactive pinewood soot was more graphitic than herbaceous biomass soot samples with the disordered carbon structure.

  • Dirin, Amir
    et al.
    Haaga-Helia University of Applied Sciences, Helsinki, Finland.
    Laine, Teemu H.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Alamäki, Ari
    Haaga-Helia University of Applied Sciences, Helsinki, Finland.
    Managing Emotional Requirements in a Context-Aware Mobile Application for Tourists2018In: International Journal of Interactive Mobile Technologies (iJIM), ISSN 1865-7923, E-ISSN 1865-7923, Vol. 12, no 2, p. 177-196Article in journal (Refereed)
    Abstract [en]

    The objective of this study was to unveil the importance of emotions and feelings in developing mobile-based tourism applications. We gathered and analyzed emotional requirements to develop a mobile context-aware application for tourists. Emotional requirements are non-functional requirements affecting users’ emotional experiences around using applications, which are important for sustainable application usage. Many tourism applications exist, but were designed without considering emotional requirements or related UX factors and emotions. We developed a proof-of-concept prototype service-based context-aware tourism application (SCATA), and users participated in the design and evaluation processes. Emotional requirements are key to sustainable usage, especially regarding security. This paper details the application design and evaluation processes, emotional requirements analysis in each design phase, and the emotional effects of content accessibility in the application’s offline mode in unknown environments. The results show that trust, security, adjustability, and reliability are important factors to users, especially in unknown environments.

  • Al-Anbari, Mohammad A.
    et al.
    Collage of Engineering, University of Babylon, Iraq.
    Thameer, Mohanad Y.
    Collage of Engineering, University of Babylon, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Landfill Site Selection by Weighted OverlayTechnique: Case Study of Al-Kufa, Iraq2018In: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 10, no 4, article id 999Article in journal (Refereed)
    Abstract [en]

    Landfill siting is a hard and complex process. For this reason, it is considered as one of the major problems in waste management. This is due to the fact that a number of factors are involved within the process such as such as inhabitants’ growth, rapid economic growth, living standards improvements, etc. In Iraq, landfill siting does not follow environmental regulations. Al-Kufa city located is located south-western part of Iraq (area of 550 km2 and inhabitants 372,760). Existing landfills are not selected according to the environmental standards. Landfill site that is required was achieved using a multi-criteria decision analysis (MCDA) and spatial overlay analysis using a geographic information system (GIS). Many factors were considered in the siting process; including geology, water supplies resources, urban centers, sensitive sites, and wells. AHP (analytic hierarchy process) method was used in weighting the criteria used. The result showed that there are six sites most suitable covering an area about (113) km2.

  • Westman, Susanne
    et al.
    Luleå University of Technology, Department of Arts, Communication and Education, Education, Language, and Teaching.
    Ulrika, Bergmark
    Luleå University of Technology, Department of Arts, Communication and Education, Education, Language, and Teaching.
    Re-considering the ontoepistemology of student engagement in higher education2018In: Educational Philosophy and Theory, ISSN 0013-1857, E-ISSN 1469-5812Article in journal (Refereed)
    Abstract [en]

    The aim of this article is to reconsider and explore the ontoepistemology of student engagement in higher education as part of a democratic education, going beyond neo-liberal groundings. This is urgent as the concept of student engagement seems to be taken for granted and used uncritically in higher education. In addition, higher education is affected by, and under pressure from, different global and societal forces, which raises questions about the purpose of education. In our exploration, we mainly draw on the philosophy of Gilles Deleuze and his co-writers Felix Guattari and Claire Parnet, but also Karen Barad and writers who are inspired by these theories. We present four arguments on which we elaborate: (1) Rethinking power relations, (2) Questioning linearity and how to use goals, (3) Appreciating pedagogical relationships as multiple voices and becoming-multiple-others, and (4) Considering assemblages, rhizomes and lines in student engagement. These arguments open up, as we argue, the possibility of rhizomatic thinking about learning in higher education where multiplicities, otherness and the unpredictable are appreciated. In addition, we regard the exploration of assemblages that are intercorporeal, affective and entangled as something powerful when reconsidering student engagement as part of democratic education.

  • Jilläng, Emil
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Making ASN.1 (Abstract Syntax Notation One) human-readable: Investigative and practical study to generalize decoding and manual validation of ASN.1 from the cellular network during run time2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    ASN.1 is a powerful formal notation divided into two parts, a specification of the data and the data itself in binary form. Creating decoders for these files can often be tedious. The purpose of this degree work is to extend current tools at Arctic Group to make an application that decodes a range of different ASN.1 specifications and data. This should be done during runtime, without needing to rebuild the application for each specification, while generating human-readable data and abstracting unwanted information. Two ways to create ASN.1 decoders were identified, and the application was designed taking heavy inspiration from a solution that stores intermediate data in a list. By not including encoding as a feature of the application a few shortcuts could be made, and the desired result could be achieved during runtime. The application was designed to include three parts. The first part was an ASN.1 parser using the Java-based tool ANTLR4. The second part matched the binary data to the information in the specification. The final part was an output formatter that abstracts and prettifies the output data to text files. The result was an application that parses at least three of the most commonly used specifications of the employer and does only have to be rebuilt when a new data type is present in the specifications. Problems arose when matching the data to the ASN.1 specifications, thus the matching and output formatting was only partially implemented. The application was evaluated by testing many different ASN.1 specifications, making sure everything was generated correctly during runtime and extending the parser to support more syntax as it was introduced in new specifications. Although the application did not support any arbitrary ASN.1 specification, it could serve as a foundation for further development to make the application truly generalized.

  • Norman, Per-Albin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Filter Materials for Sorption of Cu and Zn in Stormwater Treatment: A Batch Equilibrium and Kinetic study2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Urban stormwater is today recognized as a significant source of pollution that has contributed to the deterioration of water quality in lakes and streams. Of the pollutants, metals are commonly occurring in stormwater and can cause major damage when released into the receiving waters. A promising treatment method for removing these metals before it reaches the receiving waters is to filter the water in various filter technologies such as catch basin inserts.

    In this study, the potential of five materials to remove dissolved copper (Cu) and zinc (Zn) from stormwater was investigated. The study was initiated with batch equilibrium tests to assess the sorption capacity of the materials at different metal concentrations relevant for stormwater. This was done in both single and binary batches to investigate whether or not any competitive sorption occurred between the metals. Langmuir, Freundlich and Sips isotherm models were adapted to the obtained data. Through geochemical modelling, it was also possible to investigate whether precipitation of metals was likely. Finally, kinetic studies were conducted to investigate whether the reaction rate of Cu and Zn was relevant in the context of catch basin inserts.

    The results showed that the biochar had the highest sorption capacity followed by peat, bark, milkweed, and polypropylene. It could also be noted that Cu competed with Zn binding sites at high concentrations and that the sorption capacity of biochar, peat and bark, at concentrations between 50-100 μg/l Cu and 50-500 μg/l Zn, was sufficient to meet the limits set for stormwater emissions. For these sorbents, the reaction rate was also significant. Kinetics tests showed that at an initial concentration of 1,000 μg/l, 83% of the metals were sorbed after 5 minutes and after 10 minutes this number was 93%. Bark and peat also showed low effluent pH and leaching of dissolved organic carbon (DOC). The Langmuir and pseudo-second order equation could be well adapted to the data while geochemical modelling showed that precipitation of metals was unlikely. This suggests that chemical adsorption may be the mechanism that largely accounted for the removal of Cu and Zn.

    The results of this study can hardly be used to estimate the field performance of stormwater filters, but can be used as a basis for comparing and selecting sorbents for subsequent column tests.

  • Söderholm, Mats
    Luleå University of Technology, Department of Arts, Communication and Education.
    Att stödja för delaktighet: En kvalitativ studie av personal på LSS-boenden och deras perspektiv på delaktighet för den boende2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis