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  • Rentzelos, Theofanis
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Numerical Investigation of Rock Support Arches2019Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    The Garpenberg mine, owned by the Boliden Mining group, has established a trial area at Dammsjön orebody in order to examine the possibility of increasing the productivity of the mine. The mine uses the rill mining method with a current rill height of 15 m. In order to increase the productivity, the mine is examining the possibility of increasing the height of the rill. The trial area is located at 882 m depth surrounded by dolomite on the hangingwall and quartzitic rock on the footwall side. Rock support arches have been installed, in addition to the regular support pattern, to test their effectiveness on stabilizing the ground around the drifts. The arches have been installed in every 6 m and every 3 m in different parts of the test area. Rock samples from the trial area were brought to the university laboratory for testing. The data gathered from the laboratory tests along with the data from the monitoring of the trial area were used to develop a calibrated numerical model. A three-dimensional (3-D) model was therefore created, by using the FLAC3D numerical code. After the calibration of the model a parametric study was conducted for different rill heights and different arch spacing to investigate the performance of the arches. Specifically, the case of no arch installation along with the cases of an installed arch every 6 m and 3 m were tested, for the rill heights of 15 m, 20 m, 25 m and 30 m. The study concluded that the arches assisted in reducing the ground convergence in the production drift. The results also showed that the total height of the rill bench yields regardless of its height. After the yielding, the rockmass can no longer support itself and caves under its own weight. The larger the rill height, the larger the volume of loose rock that has to be supported and thus, higher the convergence. Furthermore, it was also observed that, significant amount of convergence in the production drift occurred during the drifting of the top drive and less during the stoping of the rill bench. This indicates that, the timely installation of the arches is an important criterion for their performance.

  • Sandberg, Oskar
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Nutti, Kenneth
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    CA UIM: Övervakning för Sametingets nätverk2019Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    Det globala konsultföretaget CGI är leverantör för Sametingets nätverk. Behovet av en förbättrad övervakning på Sametingets nätverk efterfrågades av CGI. Genom att förnya och förbättra övervakningen säkerställs en snabbare felsökning och en högre tillgänglighet. Plattformen som skulle användas för att förverkliga målet heter CA Unified Infrastructure Management (CA UIM).

     

    Eftersom slutprodukten skulle övervaka en skarp miljö så började arbetet med att upprätta en testmiljö där experiment kunde utföras. En liten del av arbetet bestod av att kartlägga det nätverk som skulle övervakas. Det huvudsakliga arbetet gick ut på att lära känna programvaran. UIM bygger på att prober utför insamling av data som sedan transporteras vidare till en gemensam databas för den specifika domänen. Databasen kan i sin tur leverera data till exempelvis dashboards på front-end sidan. 

    Följande prober har använts i vårt arbete:

    • Net_Connect – Använder ICMP för att bekräfta en enhets tillgänglighet.

    • Interface_Traffic - Övervakar nätverkstrafiken med SNMP-agenter.

    • CDM - Ansvar för övervakningen av CPU, disk och minnesutnyttjande på servrar.

     

    Efter att designen av våra dashboards var färdigställda och övervakningen fungerade så gick vi över till den skarpa miljön och upprättade samma koncept där. Arbetet presenteras sedan för CGI i Kiruna med positiva reaktioner.

  • Cabrati, Gülcan
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Hammar, Rebecka
    Luleå University of Technology, Department of Health Sciences.
    Patienters upplevelse av hemodialysbehandling: en litteraturstudie2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Vid kronisk njursjukdom är funktionen hos njurarna försämrad. Detta behandlas vanligtvis med hemodialys, som gör det arbete som njuren inte längre klarar av. Behandlingen är livslång och kräver mycket tid då det sker flera gånger i veckan. Syftet med studien var att beskriva patienters upplevelser av hemodialysbehandling. Litteraturstudien innehållande tolv kvalitativa artiklar har analyserats med kvalitativ innehållsanalys med manifest ansats. Samtliga artiklar var publicerade på engelska mellan 2009-2019 och hade hög respektive medel kvalitet. Resultatet är presenterat utifrån fyra kategorier: Att livet begränsas, som innebar att patienterna upplevde sig vara begränsade och hade brist på frihet. Att leva med en försvagad kropp, innebar att patienternas välbefinnande minskade på grund av behandlingens symtom såsom trötthet, svaghet och illamående. Att vara fast och inte ha valmöjligheter, innebar att dialysen var något patienterna behövde göra vare sig de ville eller inte och att de var beroende av behandlingen och fick ingen ledighet ifrån detta. Sist framkom att acceptera och vara gynnsamt inställd, som innebar att vissa patienter accepterat behandlingen, det fanns en tacksamhet till dialysen och behandlingen var anledningen till att de var vid liv. Denna litteraturstudien gav en ökad uppfattning om patienters upplevelser, det skulle kunna underlätta för vårdpersonal att bemöta patienten på ett professionellt sätt. Vidare forskning skulle kunna göras på KASAM kopplat till hemodialyspatienter samt vidare forskning på förbättringsarbeten inom vissa områden kring hemodialyspatienter. Exempelvis inom bemötandet samt någon slags form av sysselsättning som underlättar tiden på dialysavdelningen.

  • Johansson, Josefin
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Dahlberg, Amanda
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Hemlösa personers upplevelser av Hälso- och sjukvård: en kvalitativ litteraturstudie2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Hälso- och sjukvårdspersonal påträffar personer som lever i olika former av utsatthet i sitt arbete. Hemlösa personer är en utsatt grupp som kämpar mot unika svårigheter och har därmed även unika vårdbehov. Hemlösa personer är därför en utmanande samhällsgrupp att vårda. Hälso- och sjukvårdspersonal upplever en osäkerhet i att vårda hemlösa personer och behöver en ökad kunskap kring deras komplicerad hälsoproblem. Syftet med litteraturstudien var att beskriva hemlösa personers upplevelser av hälso- och sjukvård. En kvalitativ manifest innehållsanalys med induktiv ansats användes eftersom inifrånperspektiv med fokus på människors upplevelser studerades. Tolv vetenskapliga kvalitativa artiklar ingick i analysen. Resultatet visade att det var svårt att få tillgång till hälso- och sjukvård samt följa rekommendationer. Hemlösa personer kände sig stigmatiserade och blev behandlade som om de inte vore en människa samt att hälso- och sjukvårdspersonal kunde skapa en vårdmiljö som gav stöd och trygghet genom ett respektfullt bemötande. Hälso- och sjukvårdssystem behöver utvecklas för att hemlösa personer ska få tillgång till god individanpassad vård. Dagens hälso- och sjukvårdssystem är inte utformad för denna utsatta samhällsgrupp. I klinisk praxis behöver hälso- och sjukvårdspersonal reflektera över normer och värderingar samt ökad kunskap och utbildning om denna utsatta samhällsgrupp för att kunna arbeta med de unika utmaningar som medföljer.

  • Rolia, Florivel
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Renblom, Malin
    Luleå University of Technology, Department of Health Sciences.
    Sjuksköterskans ledarskap och dess inverkan på omvårdnadsarbete: en litteraturöversikt2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I arbetet som legitimerad sjuksköterska ingår ett ledarskap som går ut på att sjuksköterskan har en arbetsledande funktion inom ett vårdteam. Syftet med denna litteraturöversikt var att sammanställa kunskap om sjuksköterskans ledarskap och vilken betydelse det har i omvårdnadsarbetet. Två frågeställningar formulerades för att precisera syftet. En integrerad kunskapsöversikt utfördes och artiklar söktes i databaser samt manuellt. Litteratursökningen resulterade i tolv vetenskapliga artiklar som analyserades enligt en metod av Whittemore och Knafl. Frågeställning ett var: vilka egenskaper är önskvärda hos sjuksköterskan för att vara en god ledare?  I resultatet till frågeställning ett framkom fyra områden: att ha en etisk medvetenhet, att ha självkännedom, att kunna bygga relationer samt att kunna leda mot utveckling. Frågeställning två var: vilken betydelse har sjuksköterskans ledarskap för omvårdnadsarbetet? I resultatet till frågeställning två framkom tre områden: det leder till patientnöjdhet, det påverkar arbetsmiljön samt det leder till kvalitetsökning av vården. Vidare forskning i vilket stöd sjuksköterskan behöver i sin ledande roll hade varit intressant.

  • Larsson, Sofia
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Larsson, Ellinora
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Upplevelser av att återhämta sig från Anorexia Nervosa: En litteraturstudie2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • Persson, Tina
    Luleå University of Technology, Department of Arts, Communication and Education, Education, Language, and Teaching.
    Jag vill bara att det ska vara lagom svårt!: Anpassas skolans läroplan utifrån varje elevs unika förmåga?2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • Andersson, Linnea
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Sandström, Emma
    Luleå University of Technology, Department of Health Sciences.
    En kvinnas upplevelser av att leva med obotlig cancer: en analys av ett narrativ2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Att drabbas av obotlig cancer kan göra att hela ens tillvaro vänds upp och ner. Sjukdomen och tankar på döden triggar personens existentiella lidande. Sjuksköterskan har en viktig roll i patientvården att stötta och trösta och det kan vara en utmaning att vårda personer med obotlig sjukdom. Sjukdom påverkar hela människan och patientens berättelse har stor betydelse för dennes identitet. Syftet var att beskriva en kvinnas upplevelser av att leva med obotlig cancer. En kvalitativ innehållsanalys, med stöd i Graneheim och Lundmans (2004) metodartikel gjordes av ett narrativ. Analysen resulterade i sju kategorier; Inte kunna lita på kroppen, känna sig ensam och bortglömd, bli misstrodd av sjukvården, viljan att leva vidare, känna ångest och oro, inte känna någon mening och tankar om döden alltid närvarande. Närstående och vänner hade stor betydelse för personen. Känslor av ensamhet förekom ofta och sjukvårdens bemötande upplevdes både negativt och positivt. Ångest, oro och brist på mening var känslor som ofta var närvarande. Personen tänkte ofta på döden men hade en stark vilja att leva. Att leva med obotlig cancer innebär stora förändringar och utmaningar för hela människan i dennes vardag. Existentiella frågor och meningen med livet sätter hälsan på prov. Sjuksköterskan har en viktig roll i patientens vård och det ställer krav på sjuksköterskan att hen har ett personcentrerat arbetssätt samt kunskap och förståelse för hur personer med obotlig sjukdom upplever sin situation.

  • Hedberg, Rebecca
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Brandskyddssituationen i bostäder som marknadsförs åt äldre2019Independent thesis Basic level (professional degree), 210 HE creditsStudent thesis
    Abstract [en]

    Since 2010 preventive fire-safety measures in Sweden are all based on a common zero vision that reads: “No one should die or be seriously injured because of fire”. For the past half-century there has been a steady decline in fire-related deaths and in recent years that number has been around 100 each year. However, for one group of individuals that decline has ceased. For individuals older than 65 the death toll has been a steady average of 50 fire-related deaths per year for some time. These represent half of all fire-related deaths each year and the predicted population-increase in this age-group has started to cause some concern about how this will affect the death-toll.

    Individuals older than 65 primarily live in their own homes. In recent years homes specifically marketed to the elderly (in terms of safety and comfort) have taken up a larger portion of those. This increase in homes marketed to the elderly has followed a greater need for homes for the elderly as well as a Swedish principle of “home-living”. The idea is that individuals should be afforded every possibility to remain in their own homes as they age. The problem with these marketed homes is that the safety and comfort they promise is so in no other way than socially. Current fire-safety regulation sets no higher standard for these homes than for regular homes. 

    This study has examined what level of fire-safety a chosen group of build-projects for marketed homes has. The study shows that all the studied projects meet current regulations, only a few indicate higher safety-ambitions. In two of these those, the higher ambitions were enhanced warning-systems and in another two stove guards were installed in all apartments. What was more the study found that more than half of the projects were designed to require assistance from fire-rescue services in order to evacuate the building. This is particularly alarming since more than half of the fire-rescue services in Sweden reported not being able to maintain continuous service in a recent study. 

    Additionally, this study has surveyed municipal-experts for information on what ability elderly in these marketed homes have to evacuate on their own and on how they work with individually adapted fire-safety in the municipality. Fire-safety services were also surveyed for their knowledge and experience with the issue.

    In conclusion, both previous studies and the respondents to this study identify the fire-safety regulations applied to these marketed homes as an issue of significance. They all conclude that individually adapted fire-safety cannot possibly replace the individual’s capability to evacuate. Furthermore, only half of Swedish municipalities have adapted the process of individually adapted fire-safety in some way or shape. The main consequence of this is that the level of fire-safety elderly are prepared varies across the country and consequently fails to be equal.

    The issue at hand requires a multitude of solutions on a local and national scale. Some issues are relatively easily solved by government agencies providing more support to struggling, smaller municipalities. Other issues – like the lacking regulations for the marketed homes – require a review of current fire-safety regulations. It is understandable for agencies to want to meet a housing deficit, especially considering the looming demographic changes. But it should not come at the cost of elderly individuals’ safety and comfort.

  • Häggström, Elin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hållbart byggande år 2050 och styrmedel på vägen dit: En studie om potentiellt olika och motstridiga uppfattningar mellan myndigheter, forskare och byggbranschaktörer2019Independent thesis Advanced level (professional degree), 300 HE creditsStudent thesis
    Abstract [sv]

    Byggsektorn är en stor bidragande faktor till växthusgasutsläpp och hållbart byggande bör ta större plats på byggmarknaden. Att få en samsyn runt hållbart byggande är en stor utmaning då det finns många splittrade aktörer inom sektorn som ska få en gemensam målbild över vad hållbart byggande är. Detta examensarbete avser att bidra med ökad kunskap gällande utmaningar som byggsektorn står inför inom hållbart byggande. Detta genom att studera samsynen gällande mål och aktiviteter; om var vi är på väg, hur vi ska ta oss dit och vilka utmaningar som kan identifieras genom eventuella glapp mellan mål och aktiviteter samt mellan olika aktörers syn på detta.

    En omvärldsanalys genomfördes som visade på målbilder grundade i myndigheters-, byggbranschorganisationers- och forskares perspektiv. Med stöd av backcasting-metoden sammanställdes detta till en målbild om var Sverige bör vara år 2050 med fokus på växthusgasutsläpp, energiförbrukning, energianvändning samt avfall. Med utgångspunkt i denna identifierades de aktiviteter som myndigheter, byggbranschorganisationer och forskare anser ska leda till att nå målbilden. Backcasting-metoden utgör en central del i analysen av resultatet från omvärldsanalysen och bidrar till en diskussion om var det potentiellt kan finnas glapp eller olika och motstridiga uppfattningar om hållbart byggande med särskilt fokus på styrmedel. Med särskilt fokus på styrmedel avses var styrmedel kunnat identifieras, var det saknats och var det skiljts sig åt i uppfattningen om vilka styrmedel som behövs. Återigen med stöd av backcastingen diskuteras den sammanställda målbilden och de identifierade aktiviteterna sedan ur ett företagsperspektiv med stöd av resultatet från en intervjustudie med fyra byggaktörer.

    Slutsatser som kunnat dras är att inom vissa aktiviteter finns inte styrmedel identifierade utifrån alla perspektiv. I omvärldsanalysen identifieras styrmedel som något som ska ge incitament till begränsning eller ökning av en vara eller tjänst och en brist på styrmedel skulle kunna vara resultatet av olika eller motstridiga uppfattningar gällande vem eller vilka som ska bidra med det.

    Utifrån omvärldsanalysen, backcastingen och intervjustudien kan det urskiljas att det finns en övergripande samsyn runt målbilder, mindre samsyn runt vägen dit och på vem eller vilka som ska ansvara för att aktiviteterna på vägen dit ska genomföras. Mycket av det aktörerna nämner och pratar om går att koppla samman och väva in i aktiviteterna samt den sammanställda målbilden för år 2050, och mycket av det som identifierats i omvärldsanalysen tas hänsyn till av aktörerna.

    Slutligen kan resultatet av omvärldsanalysen, backcastingen och intervjustudien tolkas som att det kommer krävas tydligare styrmedel för att kunna knyta ihop säcken. Detta inte bara för att uppnå den sammanställda målbilden utan för att skapa en större överensstämmande bild av det hållbara byggandet i Sverige mellan olika aktörer.

  • Reiner, Florian
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Simulation of Scientific VHF Telemetry Data for the French Payload of the SVOM Satellite2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Space Variable Objects Monitor (SVOM) is a future French-Chinese satellite mission which is dedicated to the observation and characterisation of Gamma Ray Bursts (GRBs). When a GRB is detected by the satellite, the position and initial characterisation data are transmitted to ground via a VHF telemetry link, in order to trigger immediate follow-up observations of the transient GRB afterglow by ground-based telescopes. To optimise the prioritisation of this telemetry flow in various scenarios, detailed simulations of the VHF telemetry are required.

    In this thesis, a new telemetry simulator was thus developed: the MXT VHF Data Simulator. This simulator generates all VHF messages of the Micro X-ray Channel Telescope (MXT) instrument that would be expected during a typical operational scenario.  Each message is constructed byte by byte, with the required data formats, encodings and packet structures as specified by the SVOM telemetry standards and the MXT VHF TM specification database. To generate the scientific packet contents several approaches were combined. An existing camera frame simulator, developed at the LAL institute, was modified to simulate raw photon data for the given scenario, generating a set of binary camera frame files which is then parsed and integrated by the MXT VHF Data Simulator. MXT instrument scientists provided an example GRB profile with the temporal evolution of certain GRB parameters. In addition, several parameters were simulated manually, with an effort to achieve as realistic contents as reasonably possible, and in coordination and discussion with the MXT instrument scientists and software engineers. The output of the simulation consists of a set of MXT VHF telemetry files in binary and CSV formats.

    To verify the correct formatting and contents of the data, the files were validated using the internal CNES telemetry analysis framework PrestoTools. This analysis confirmed correct formatting and encodings in accordance with the telemetry specifications, as well as the expected data in the packet contents. Finally, the resulting data was integrated into the CNES VHF Simulator, and an analysis of a full VHF telemetry scenario with all four instruments was performed for the Data Challenge 1 (DC1) systems test scenario.

  • Hagland, Emma
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Uppkopplad utrustning för insamling av data: Och hur det kan förbättra en lastbilsmontering2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • Dahlman, Malin
    et al.
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Thomasdotter, Ruth
    Luleå University of Technology, Department of Health Sciences, Nursing Care.
    Omvårdnadsbehov hos personer som lever med stomi: en kunskapsöversikt2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    År 2015 fanns det 43 000 personer som levde med stomi i Sverige. Somsjuksköterska är det stor sannolikhet att träffa denna patientgrupp. I yrkesrollensom sjuksköterska ingår att identifiera omvårdnadsbehov till syfte att förbättra,bevara eller återfå hälsa med bästa möjliga välbefinnande och livskvalitet.Syftet med studien var att sammanställa kunskap om omvårdnadsbehov förpersoner som lever med stomi. Utifrån syftet handlade frågeställningarna omsvårigheter och behov hos denna grupp, samt hur sjuksköterskan kan mötadessa behov. En integrerad kunskapsöversikt genomfördes, den systematiskalitteratursökningen resulterade i 18 studier som granskades och analyserades.Resultatet visade på svårigheter som en förlorad autonomi på grund av enförändrad kropp, förändrad vardag och problem att hantera stomin. Resultatetvisade på behov av acceptans, kunskap och autonomi, för att stötta behoven vardet viktigt att sjuksköterskan gav en individanpassad omvårdnad och stöd.Denna kunskapsöversikt kan bidra till en ökad insikt av den personcentreradeomvårdnadens betydelse för enskilda patientgrupper. Föreslagna interventionerär grundlig information pre- och postoperativt rörande alla aspekter runt stominoch god uppföljning efter utskrivning från sjukhuset.

  • Al-Ansari, Nadhir
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Adamo, Nasrat
    Consultant Engineer, Norrköping, Sweden.
    Sissakian, Varoujan
    University of Kurdistan, Hewler, KRG, Iraq. Private Consultant Geologist, Erbil, Iraq. .
    Hydrological Characteristics of the Tigris and Euphrates Rivers2019In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 9, no 4, p. 1-26Article in journal (Refereed)
    Abstract [en]

    The Middle East is considered as an arid to a semi-arid region where the annual rainfall does not exceed 166 mm/y. Water shortage issue within this area is one of the prime issues of friction and tension between the countries of the Middle East. Iraq is located within the Middle East. It covers an area 437072 square kilometer with a population of 38.27 million.  Iraq used to be considered rich in its water resources due to the presence of the Tigris and Euphrates Rivers. The catchments of these rivers are shared with Turkey, Syria, Iran and Saudi Arabia. Building of dams in the upper parts of the catchment since the seventies as well as climate change affecting the region caused water shortage problems in Iraq. The flow of the two main rivers decreased tremendously. To overcome this problem, prudent water management plan is required. Such plan should include the use of non-conventional water resources, new irrigation techniques, public awareness, and new water management strategies.  This will help to reduce the impact of water shortage problems.

  • Eriksson, Linn
    et al.
    Luleå University of Technology, Department of Health Sciences.
    Eriksson, Pernilla
    Luleå University of Technology, Department of Health Sciences.
    Personers upplevelse efter att ha genomgått en viktreducerande operation: En litteraturstudie2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Övervikt och fetma är ett ökande folkhälsoproblem över hela världen, och så även dess följdsjukdomar såsom diabetes, högt blodtryck och cancer. Viktreducerande operationer ses som den mest effektiva metoden för gravt överviktiga personer att minska i vikt. Syftet med denna litteraturstudie var att studera människors upplevelser efter att de genomgått en viktreducerande operation. Studien genomfördes som en kvalitativ manifest innehållsanalys med induktiv ansats, eftersom fokus var på människors upplevelser.10 kvalitativa artiklar valdes ut och analyserades vilket resulterade i tre kategorier: Att upplevelsen av att hopp och förväntningar blandas med oro, skuld och skam. Att uppleva en förändrad relation till mat och känslan av förlust och att relationen till den egna kroppen förändras. En slutsats som drogs var att personer som genomgått en viktreducerande operation kan uppleva ett lidande i form av livslidande eller sjukdomslidande på grund av de förändringarna som sker efter operationen. Förändringarna kan skapa en oro och upplevelser av att vara begränsad i livet. I klinisk praxis så behöver hälso- och sjukvårdspersonal skapa en god relation, fördela makten jämnt mellan parterna, lyssna på-, tro på- och respektera personerna. Detta för att kunna stärka deras egen självkontroll och egenvård.

  • Rönnerfjäll, Victor
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Laser Hardening for Application on Crankshaft Surfaces Using Non-Uniform Beam Intensity Distributions2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A controlled continuous laser output using a circular geometry with a gaussian intensity distribution was used to harden the surface of a particular metal specimen (44MnSiVS6). Said beam operated within a relatively small power interval, just barely past the melting point. The resulting martensite track was shown to expand laterally at a positive exponential rate, with respect to the energy input. This was furthermore accompanied with an increase of the average slope at each lateral edge. The thickness was seen to expand at a significantly slower rate (by about one order of magnitude), with declining efficiency in regard to the energy input used. Thermal measurements along the surface indicated somewhat uniform temperature patterns within a relatively large area surrounding the middle of the beam spot. Though a slight elevation in temperature was often noted in the vicinity of its centre. In addition to using a gaussian beam, three other intensity distributions were utilized. The results obtained from said distributions may suggest effectual alterations to occur in terms of the shape and extent of the resulting martensite zone, if the spread of the gaussian intensity profile is allowed to be modified. Ideally, this would be carried out while still remaining close to the melting point, as well as keeping the spot size unchanged. A series of vicker's hardness measurements was carried out for each track induced by a different beam distribution. A clear transition in hardness was noted across the perceived boundary between the martensite zone and the base material, confirming the legitimacy regarding the phase identification.

  • Nordström, Emilia
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Dineva, Savka
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Nordlund, Erling
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Back Analysis of Short-Term Seismic Hazard Indicators of Larger Seismic Events in Deep Underground Mines (LKAB, Kiirunavaara Mine, Sweden)2019In: Pure and Applied Geophysics, ISSN 0033-4553, E-ISSN 1420-9136Article in journal (Refereed)
    Abstract [en]

    Back analysis for evaluation of the merits of the short-term seismic hazard indicators (precursors) used in the mines and their potential application for early warning was carried out for fourteen seismic events that potentially caused damage in Kiirunavaara Mine, Sweden, selected according to our designed criteria. Five short-term hazard indicators: Seismic Activity Rate (SAR), Cumulative Seismic Moment (CSM), Energy Index (EI), Cumulative Apparent Volume (CAV) and Seismic Apparent Stress Frequency (ASF) were tested. The behaviour of the indicators was studied using the parameters of all seismic events within a sphere around the hypocenter location of the analyzed seismic source within one month before the main (damaging) event. The size of the sphere equals the estimated radius of the analyzed seismic source (area of inelastic deformation). mXrap software (Australian Centre for Geomechanics) was used for data visualization, manipulation, analysis and extraction. The results from the main analysis showed a good agreement between the expected and actual behaviour of the SAR, CSM and CAV indicators. In overall, CSM and CAV ranked the highest positive/expected behaviour followed by SAR (Table 3). The EI and ASF ranked lowest and showed to be sensitive to the number of events within the source sphere. The rate of false warnings and missed warnings was also investigated for the 25 days-long period before the damaging events. A similar trend was observed as for the main analysed event. The results from this study can be used for further improvement of the short-term hazard estimations and early warning system in deep underground mines.

  • Al-Jabban, Wathiq
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Engineering Dept., University of Babylon, Babylon, Iraq.
    Laue, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Effect of Disintegration Times of the Homogeneity of Soil prior to Treatment2019In: Applied Sciences, E-ISSN 2076-3417, Vol. 9, no 22, article id 4791Article in journal (Refereed)
    Abstract [en]

    This paper presents an experimental study to investigate the effect of various disintegration times on the homogeneity of pre-treated natural soil before mixing with cementitious binders. Various disintegration times were applied, ranging from 10 s to 120 s. Four different soils were used with different characteristics from high, medium and low plasticity properties. Visual and sieving assessment were used to evaluate the best disintegration times to allow for a uniform distribution of water content and small-sized particles that would produce a uniform distribution of the binder around the soil particles. Results showed that a proper mixing time to homogenize and disintegrate the soil prior to treatment depended on several factors: soil type, water content and plasticity properties. For high plasticity soil, the disintegration time should be kept as short as possible. Increasing the disintegration time ha negative effects on the uniformity of distribution of the binder around soil particles. The homogenizing and disintegration time were less important for low plasticity soils with low water content than for medium to high plasticity soils. The findings could assist various construction projects that deal with soil improvement through preparation of soil before adding a cementitious binder to ensure uniformity of distribution of the binder around soil particles and obtain uniform soil–binder mixtures

  • Uddin Ahmed, Tawsin
    et al.
    Department of Computer Science and Engineering, University of Chittagong, Bangladesh.
    Hossain, Mohammad Shahadat
    University of Chittagong, Bangladesh.
    Alam, Md. Jahangir
    Chittagong University of Engineering & Technology.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    An Integrated CNN-RNN Framework to Assess Road Crack2019In: Proceedings of the 2019 22nd International Conference on Computer and Information Technology (ICCIT), 2019Conference paper (Refereed)
    Abstract [en]

    Road crack detection and road damage assessment are necessary to support driving safety in a route network. Several unexpected incidents (e.g. road accidents) take place all over the world due to unhealthy road infrastructure. This paper proposes a deep learning approach for road crack detection and road damage assessment which will contribute to the transport sector of a country like Bangladesh where a plethora of roads undergo the crack problem. The proposed model consists of two phases. In the first phase, the model is trained using transfer learning (VGG16) to detect the existence of crack on the road surface. In the second phase, an integrated framework, combining CNN (VGG16) and RNN (LSTM), is trained to classify the crack in one of the two categories-severe and slight. After experiments, the validation accuracies obtained by the proposed models (VGG16 and VGG16-LSTM) are respectively 99.67% and 97.66%.

  • Homsi, Rajab
    et al.
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia.
    Shiru, Mohammed Sanusi
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia. Department of Environmental Sciences, Faculty of Science, Federal University Dutse, Dutse, Nigeria.
    Shahid, Shamsuddin
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia.
    Ismail, Tarmizi
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia.
    Harun, Sobri Bin
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Chau, Kwok-Wing
    Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, Peoples People’s Republic of China.
    Yaseen, Zaher
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Precipitation projection using a CMIP5 GCM ensemble model: a regional investigation of Syria2020In: Engineering Applications of Computational Fluid Mechanics, ISSN 1994-2060, E-ISSN 1997-003X, Vol. 14, no 1, p. 90-106Article in journal (Refereed)
    Abstract [en]

    The possible changes in precipitation of Syrian due to climate change are projected in this study. The symmetrical uncertainty (SU) and multi-criteria decision-analysis (MCDA) methods are used to identify the best general circulation models (GCMs) for precipitation projections. The effectiveness of four bias correction methods, linear scaling (LS), power transformation (PT), general quantile mapping (GEQM), and gamma quantile mapping (GAQM) is assessed in downscaling GCM simulated precipitation. A random forest (RF) model is performed to generate the multi model ensemble (MME) of precipitation projections for four representative concentration pathways (RCPs) 2.6, 4.5, 6.0, and 8.5. The results showed that the best suited GCMs for climate projection of Syria are HadGEM2-AO, CSIRO-Mk3-6-0, NorESM1-M, and CESM1-CAM5. The LS demonstrated the highest capability for precipitation downscaling. Annual changes in precipitation is projected to decrease by −30 to −85.2% for RCPs 4.5, 6.0, and 8.5, while by < 0.0 to −30% for RCP 2.6. The precipitation is projected to decrease in the entire country for RCP 6.0, while increase in some parts for other RCPs during wet season. The dry season of precipitation is simulated to decrease by −12 to −93%, which indicated a drier climate for the country in the future.

  • Sperens, Martin
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Dynamic Memory Managment in C++2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Memory allocation is an important part of program optimization as well as of computer architecture. This thesis examines some of the concepts of memory allocation and tries to implement overrides for the standard new and delete functions in the c++ library using memory pools combined with other techniques. The overrides are tested against the standard new and delete as well as a custom memory pool with perfect size for the allocations. The study finds that the overrides are slightly faster on a single thread but not on multiple. The study also finds that the biggest gain on performance is to create custom memory pools specific to the programs needs. Lastly, the study also lists a number of ways that the library could be improved

  • Lundqvist, Mathias (Musician)
    Luleå University of Technology, Department of Arts, Communication and Education, Music, media and Theatre.
    Jakob Norgren Jazz Orchestra: live på Stockholm Jazz Festival 20192019Artistic output (Unrefereed)
  • Al Amli, Ali Sabah
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Al-Mustansiriyah University, Baghdad, Iraq.
    Al-Ansari, Nadhir
    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.
    Study Numerical Simulation of Stress-Strain Behavior of Reinforced Concrete Bar in Soil using Theoretical Models2019In: Civil Engineering Journal, ISSN 2476-3055, Vol. 11, no 5, p. 2349-2358Article in journal (Refereed)
    Abstract [en]

    Nonlinear analysis for reinforced concrete members (R.C.) with two types of bars also with unsaturated and saturated soils was used to represent the models. To control the corrosion in the steel bar that used in R.C. member and decrease the cost, the geogrid with steel bar reinforcement are taken in this study to determine the effect of load-deflection and stress-strain relationships. The finite element method is used to model the R.C. member, bars and soil. A three-dimensional finite element model by ABAQUS version 6.9 software program is used to predict the load versus deflection and stress versus strain response with soil. The results for the model in this study are compared with the experimental results from other research, and the results are very good. Therefore, it was concluded that the models developed in this study can accurately capture the behavior and predict the load-carrying capacity of such R.C. members with soil and the maximum stresses with strains. The results show plastic strain values in the R.C. member with saturated soil are larger than their values in unsaturated soil about (54%, 58%, and 55% and 52%) when the geogrid ratios are (without geogrid, 60%, 40% and 20%) respectively, with the same values of stresses.

  • Alzeyadi, Ali
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Laue, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Alattabi, Ali
    School of Civil Engineering, Liverpool John Moores University, Liverpool, United Kingdom.
    Study of Biomass Bottom Ash Efficiency as Phosphate Sorbent Material2019In: Civil Engineering Journal, ISSN 2476-3055, Vol. 11, no 5, p. 2392-2401Article in journal (Refereed)
    Abstract [en]

    Excessive richness of nutrients in water bodies such as rivers, lakes and ponds lead into deterioration of aquatic life as a results of dense growth of algae. Phosphate is one of the main nutrients that should be controlled to prevent this serious issue. Utilizing low cost material as a phosphate sorbent is offering a treatment method characterized as a sustainable solution. In this study the efficiency of biomass bottom ash BBA as phosphate sorbent material from aqueous solution is investigated. Batch experiments were undertaken, in which a particular mass of BBA was brought into contact with the phosphate solution. The experiments studied the influence of pH (different phosphate solutions were prepared with pH range 4 to 8), temperature (adsorption capacity measured at the temperature range of 10 to 30 °C), and contact time. In addition, the adsorption isotherm models were also applied to better understand the mechanism of phosphate sorption by BBA. The results revealed that the bonding between the cations (BBA surface) and anions (phosphate solution) is significantly affected by the pH of the solution. BBA presents an excellent phosphate sorption, especially, at low pH value and temperature around 20 oC. The method of this research can be adopted as a followed strategy for examination the capability of selected material for phosphorus removal from wastewater.

  • Al-Kahwati, Kammal
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Outlier detection on sparse-encoded vibration signals from rolling element bearings2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The demand for reliable condition monitoring systems on rotating machinery for power generation is continuously increasing due to a wider use of wind power as an energy source, which requires expertise in the diagnostics of these systems. An alternative to the limited availability of diagnostics and maintenance experts in the wind energy sector is to use unsupervised machine learning algorithms as a support tool for condition monitoring. The way condition monitoring systems can employ unsupervised machine learning algorithms consists on prioritizing the assets to monitor via the number of anomalies detected in the vibration signals of the rolling element bearings. Previous work has focused on the detection of anomalies using features taken directly from the time or frequency domain of the vibration signals to determine if a machine has a fault. In this work, I detect outliers using features derived from encoded vibration signals via sparse coding with dictionary learning. I investigate multiple outlier detection algorithms and evaluate their performance using different features taken from the sparse representation. I show that it is possible to detect an abnormal behavior on a bearing earlier than reported fault dates using typical condition monitoring systems.

  • Järnkrok, Siri
    Luleå University of Technology, Department of Arts, Communication and Education.
    Den trygga men trista vägvisaren: Sångelevers erfarenheter av notanvändning i gymnasieskolan2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Den föreliggande studien ämnade undersöka sångelevers erfarenheter av att använda noter inom musikämnena på gymnasiet. Problematiken som föranledde studien var att sånginstrumentet sitter inuti människokroppen, vilket gör sånginstrumentet till ett speciellt instrument som kan ha svårare att pricka rätt noterade toner än andra instrument som är utomkroppsliga. Detta leder till att sångare behöver öva och få erfarenheter av att musicera via noter för att lättare kunna känna och pricka de noterade tonerna med hjälp av sina röster. Syftet med studien var att beskriva sångelevers erfarenheter av att använda noter i sitt musicerande. De frågeställningar som använts i studien har berört hur sångeleverna använder noter i sitt musicerande, hur sångeleverna erfarit notskrift som ett komplext redskap i sitt musicerande samt vilken betydelse som noter har för deras musicerande. Frågeställningarna för studien konstruerades efter ett sociokulturellt perspektiv som var den vetenskapliga ansatsen för studien. Sex kvalitativa intervjuer genomfördes med sångelever på en gymnasieskola. Datan analyserades sedan genom kvalitativ innehållsanalys där sociokulturella teman bildades, exempelvis i vilka musikaliska hur de använde noter och betydelsen av att kunna använda noter i sitt musicerande. Resultatet visade att sångeleverna använde noter i många av musikämnena i gymnasieskolan, men att det förekom vissa skillnader i notanvändningens omfattning mellan ämnen samt användningen av noter i skolan och på fritiden. Notanvändning var något som sångeleverna förknippade med skolan och noter beskrevs som tråkigt men användbart i musicerandet. Resultatet av studien visade att sångelever helst använde noter när de skulle lära sig ett nytt stycke, men lämnade helst noterna när de lärt sig stycket för att inte bli för låsta vid noterna.

  • Jönsson, Hugo
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Numerical simulations of the pressure time method in a full-scale turbine2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Efficiency measurements are an important part of operating and maintaining a hydroelectric turbine. In order to calculate the efficiency, one need a method to accurately measure the flow rate. The pressure time method is a way to calculate the flow rate from pressure measurements, which are done during a transient. This master thesis aims to evaluate the possibility to implement the pressure time method in prototype turbine with variable intake cross-section. To this end, numerical simulations of the method on a prototype situated in Porjus were performed. The work was compared against experimental data obtained on the machine. Three operating points were evaluated, and two different numerical simulations were done for every operating point, with and without guide vanes. For the simulation without guide vanes, the deacceleration stems from the control of the flow at the outlet. The curve for the mass flow at the outlet was calculated with the pressure time method with data from the experiments. For the simulation with guide vanes the deacceleration stems from the guide vanes closing. The results from the simulations gives a reasonable fit to the experimental data. There is a difference between the simulations with and without guide vanes, though both are on the same magnitude. The largest differences between the simulations and experimental data is theorized to be due to either the assumption of an axisymmetric flow or the outlet boundary conditions.

  • Gyhlesten Back, Jessica
    et al.
    Surreddi, Kumar
    Materials Technology, Dalarna University, Falun, Sweden.
    Microstructure analysis of martensitic low alloy carbon steel samples subjected to deformation dilatometry2019In: Materials Characterization, ISSN 1044-5803, E-ISSN 1873-4189, Vol. 157, article id 109926Article in journal (Refereed)
    Abstract [en]

    Low alloy martensitic steels are commonly used in structural and wear resistant applications due to their excellent mechanical properties and abrasion resistance. Martensite phase is generally achieved by rapid cooling, and prior deformation in the austenite region also affects the martensite transformation. It is important to understand the martensite transformation when there is deformation above Ae3. Deformation and quenching simulations have been performed using dilatometry on a low alloy carbon steel. The aim was to determine the influence of deformation above Ae3 (prior deformation) on, firstly, the austenite grain size and shape, and secondly, the martensitic microstructure and variant selection. In addition, the hardness of the martensitic structure due to prior deformation has been investigated. The experimental results obtained from electron backscatter diffraction and microhardness tests on the deformation dilatometry test samples were analysed. The orientation relationship Kurdjumov-Sachs has been used to analyse the martensitic variants. The results revealed a deeper understanding of prior austenite grain structure's effect on the martensitic transformation kinetics and its morphology. The martensite laths' misorientation interval 15–48° were used to visualise the prior austenite grain size. The martensitic lath structure is more refined due to increased prior deformation. Shorter martensite formation time promotes a single dominating packet within the prior austenite grain.

  • Hansson, Johan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    The Klein-Alfvén cosmology revisited2019In: Journal of Physics Communication, E-ISSN 2399-6528, Vol. 3, no 11, article id 115001Article in journal (Refereed)
    Abstract [en]

    The Klein-Alfvén model is based on the pragmatic belief that also cosmology, just like all other fields of physics, should be based on physical laws independently tested in the laboratory. It actually has a number of attractive features, described in this article. As almost all matter in the known universe is in the plasma state, the model is by necessity based on both gravity and electromagnetism, and as most cosmic plasmas are inhomogeneous and magnetized, it is automatically inhomogeneous (as is the real universe). It is not perfect (no models are), but many of the outstanding unsolved 'problems' of the contemporary standard big bang-model of cosmology are either solved/sidestepped by, or non-existent in, the Klein-Alfvén model. One should remember that the standard model of cosmology also is just that—a model, and highly idealized at that, with many ad hoc ingredients and a large number of free parameters and hypothetical ingredients that are fixed only through comparison with cosmological data in a global best-fit fashion. It is not, and should never be considered to be, sacrosanct. If a comparable number of man-hours had been invested in the direction of the Klein-Alfvén model it is plausible that it would describe the real observed universe as good as, or even better than, the big bang-model—with much fewer speculative additions to known physics.

  • Edman, Jennifer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Deriving characteristics of thin cirrus clouds from observations with the IRF lidar2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Cirrus clouds play an important role in radiative transfer, and thus have impact on the energy balance of the atmosphere and the climate of the Earth. Furthermore, they occur often and cover large areas globally at any time. Nevertheless, cirrus clouds are poorly studied, especially in the polar regions. Cirrus clouds are present in a large amount of the 14 years of data produced by the lidar at the Swedish Institude of Space Physics (IRF), but has not been studied to a large extent. A lidar is an active remote sensing instrument using a laser. This master's thesis develops and improves programs for analysis of cirrus clouds from this lidar data. It also performs analysis of six case studies chosen from the available data, and statistics of these six cases.

    The parameters calculated for each date are the cloud top, base and mean altitude, the geometrical thickness, the depolarisation ratio, the backscatter ratio (BSR), the backscatter coefficient, the extinction coefficient, the optical thickness and the number of cloud layers. No clear correlation between the optical thickness and the cloud top, base or mean altitude was found. There seems to be a weak correlation between increased optical thickness and increased geometrical thickness, which is not unreasonable. The mean cloud layer top altitude was 11.82 km and the mean cloud base was 10.36 km. The mean optical thickness for a cloud layer was 1.46 km, and the average of the cloud layer mean altitude was 11.09 km. It should be noted that the statistical analysis is based on only six cases with a total observation time of no more than 37 hours. A far larger dataset is needed in order to obtain any statistically signicant conclusions. The effect of averaging is studied, and it is concluded that averaging over altitude reduced the noise and facilitated the interpolation more than averaging over time did.

    Different approaches to obtain the molecular backscatter coefficient are compared, as well as the effect on the simulated molecular signal. Two of these approaches calculate the molecular backscatter coeffcient with input of the temperature and pressure either as continuously measured ground vales from the weather station at IRF or as radiosonde profiles for a specific time. In the other two, the molecular backscatter coeffcient is obtained from ECMWF data and from the standard atmosphere. Differences in the range 12-35% between the methods are found.

    Different approaches to calculate the backscatter ratio (BSR) are also compared. At cirrus altitudes, the decrease in the signal due to the molecular cloudfree part of the atmosphere is still strong, and finding the top and base separately by comparison with the standard deviation of the signal is proven a better method than interpolating between the point where the signal starts to increase and the point where it reaches the same signal value again. Height-normalising the signal provides a more robust method.

    For thin cirrus, the signal is not significantly attenuated above the cloud layer, and it is found that a method based on the ratios between the measured signal and the simulated molecular signal at cloud top and base did not produce reliable results for the optical thickness.

    In addition to analysing data and data processing methods, new data processing tools in MATLAB have been developed and existing functions have been improved. These will be valuable for continued studies with the IRF lidar, for cirrus as well as PSCs and thick and/or low-altitude clouds.

  • Tneh, Shao Heung
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Feasibility Study on Implementing IVF Hardware to Achieve Human Reproduction in Space2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • Faizi, Ana
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Information Security Risk Assessment in Cloud2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This research addresses the issue of information security risk assessment (ISRA) on cloud solutions implemented for large companies. Four companies were studied, of which three used cloud services and conducted ISRA, while one provided cloud services and consultancy to customers on ISRA. Data were gathered qualitatively to (1) analyze the cloud using companies’ practices and (2) to identify regularities observed by the cloud providing company. The COAT-hanger model, which focuses on theorizing the practices, was used to study the practices. The results showed that the companies aimed to follow the guidelines, in the form of frameworks or their own experience, to conduct ISRA; furthermore, the frameworks were altered to fit the companies’ needs. The results further indicated that one of the main concerns with the cloud ISRA was the absence of a culture that integrates risk management. In addition, the companies’ boards lacked interest in and/or awareness of risks associated with the cloud solutions. Finally, the finding also stressed the importance of a good understanding and a well written legal contract between the cloud providers and the companies utilizing the cloud services.

  • Åberg, Daniel
    Luleå University of Technology, Department of Arts, Communication and Education.
    Lärandet som bara hänger på väggen: En studie om musikens närvaro i skolan och fritidshemet ur ett sociokulturellt perspektiv2019Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this study was to investigate why musical instruments are not used more freely and frequently during activities as recess or at the after-school centres. A survey was executed among primary school staff in Piteå municipality, Sweden. The survey addressed past experience of musical activities, interest in music as well as individual extent of musical education. Participants were further asked to give a recollection of the accessibility of musical instruments in their workplace and eventually to reflect upon how satisfied they were with current accessibilities and work procedures considering the use of musical instruments. The outcome of the survey shows that there is a high accessibility of musical instruments in the primary school organization of Piteå municipality and that elementary teachers, as well as after-school centre teachers, often have formal musical education in their professional training. Despite these seemingly good conditions regarding musical practice, music is still treated differently from other topics and school activities. This could indicate that there are other elements, apart from actual musical competence, that are the source of these misconceptions and insecurities concerning musical instruments. One such element could be the individual experience of musical training and views on musical competence mediated within former teacher-student relations. Other elements include discourse and social structures within the teaching community, connected to views in larger society on culture and musicality, that could be the real cause of musical instruments not being used outside of musical classes. This study raises the question of what is to be prioritized in the school system. Should music teachers still be the only ones “allowed” to play instruments? Or should school staff put aside their own opinions and insecurities so that children may have a rich learning experience in music which further promotes development and progress?

  • Öhman, Julia
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Att trivas på sitt arbete: En kvalitativ studie om soldater och officerares upplevelser av arbetsplatsen2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A job is not only an economic factor for the individual; the work also has a great impact on the individual's well-being. It is therefore a prerequisite for employees to be happy at work, which places demands on the workplace. The purpose of the study is to investigate what soldiers and officers have for experiences of job satisfaction. This is answered by studying a specific company on an aircraft fleet within the Swedish Armed Forces based on these research questions: How do the informants experience their work situation at the company? What difficulties and opportunities can be identified based on the informants' work situation and how can these be understood? The thesis is based on a qualitative method and the empirical data has been collected through interviews with four officers and four soldiers. The theoretical framework is based on previous research on employees and job satisfaction, Herzberg's two-stage model and Karasek and Theorell's demand- control-support model. The results of the study show that both the soldiers and the officers feel that the high workload of the company causes the work situation to be perceived as worse. The informants also feel that they do not get paid for the work they do, that the workload prevents them from developing, that everyone does not get feedback in the way they had wanted and that the goals and requirements that are set for the function sometimes are too unclear. Furthermore, the results show that the officers and soldiers generally agree on how well-being is generally experienced at the company. The main difference between the soldiers and the officers is that the soldiers feel that their work situation is affected for the worse because they do not have the same powers to make decisions within the organization. What the informants especially feel is contributing to a more pleasant work situation is the good cohesion between the employees. The informants feel that their work situation is affected to a lesser extent by a number of aspects, but nevertheless the majority of the informants want to continue working at the company.

  • Hari Krishnan, Prem Kumar
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Design and Analysis of a Dynamic SpaceWire Routing Protocol for Reconfigurable and Distributed On-Board Computing Systems2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Future spacecrafts will require more computational and processing power to keep up with the growing demand in requirements and complexity. ScOSA is the next generation on-board computer developed by the German Aerospace Centre (DLR). The main motivation behind ScOSA is to replace the conventional on-board computer with distributed and reconfigurable computing nodes which provides higher performance, reliability, availability and stability by using a combination of the COTS components and reliable computing processors that are space qualified. In the current ScOSA system reconfiguration and routing of data between nodes are based on a static decision graph. SpaceWire protocol is used to communicate between nodes to provide reliability. The focus of the thesis is to design and implement a dynamic routing protocol for ScOSA which can be used in future for not only communicating between the nodes but also for reconfiguration. SpaceWire IPC is a customized protocol developed by DLR to provide communication between the nodes in a distributed network and to support monitoring, management and reconfiguration services. The dynamic routing protocol proposed in this thesis is primarily derived from the monitoring mechanism used in the SpaceWire IPC. PULL type monitoring mechanism is modelled and simulated using OMNeT++. The results obtained provide a qualitative outlook of the dynamic routing protocol implemented.

  • Högberg, Robert
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Arrowhead Framework Database System for Storage and Retrieval of Vehicle Signals2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Logging data is important in the digital world, both in the present and in the future. Using a database is a common way to store and retrieve data. Database prosumer system is a concept that may be the solution to many of the problems regarding data logging in the fourth industrial revolution.

    Earth-moving machines are evolving to being automatically operated, which demands scalable means for data management. Several software systems are needed to achieve a solution of this sort. A system to collect sensor data from the actual machine, a system to store the data and retrieve it, and systems that analyze, predict and actuate on that data.

    This thesis has its focus on storage and retrival of vehicle signal data, by implementing a Database system with the ability of easy update, adaptation and reuse in mind (quality attributes). The Arrowhead Framework, based on Service Oriented Architecture, is designed to handle communication between heterogeneous systems with cybersecurity. The first objective was to investigate if the Arrowhead Framework could guide towards a solution of the system, with the quality attributes in mind. The second objective was to examine what the consequences regarding batching data points to a database could be. InfluxDB and MongoDB are the databases used during the test.

    The Database System is implemented in Java containing four different modules. Client Common which holds necessary Arrowhead Framework resources. The Database Module, responsible for all database related functionality. The Database Provider which provides services regarding access of sensor data, and the Database Consumer responsible for collecting sensor data from different provider system(s).

    The system was tested by consuming a service at a Can Bus Provider, which is polling RPM data from a car. The rpm data is then stored in the implemented database. The test indicated that Arrowhead Framework can provide such a solution to achieve easy update, adaptation and reuse, on a small scale, old and in some cases non-existent documentation of the framework is holding the practical usage back.

    The result of batching data points concluded that the performance of InfluxDB writing operation improves with data point batching regards to performance, by writing several data points at once. MongoDB was not affected in the same way as InfluxDB, due to its fast single writing operation.

  • Jansson Högberg, Johan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Data Acquisition using Arrowhead Framework for Condition Based Maintenance of Industrial Equipment2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As Industry 4.0 and Internet of Things are established across factories and enterprises, the interest for learning more about these concepts and the possibilities they provide for condition based maintenance is expressed by a factory in Sweden. By addressing the aspects of Internet of Things and Industry 4.0, a system for performing data acquisition from sensors in an industrial environment is developed using Arrowhead Framework. This framework is evaluated around its suitability for this kind of application, and regarding what the framework may provide to the factory compared to other solutions and systems. A solution featuring a system based on Arrowhead Framework is developed, implemented, and briefly tested. The system is successful in performing data acquisition, and Arrowhead Framework is considered a viable option that may be used to provide a system tailored for different purposes, presumed that the factory is prepared to allocate resources on developing a solution around it.

  • Lubbad, Manas
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Kriterierna för lämplig vårdnadshavare: En studie i samband med inkorporeringen av bankonventionen i svensk rätt2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • Martinez Cano, Pablo
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Thermomechanical Design and Analysis of the Lisa Phase Measurement System2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Gravitational Waves (GWs) are ripples in the curvature of spacetime that propagate as waves at the speed of light while travelling basically undisturbed from the moment of their creation by accelerated masses. GWs provide unique information about astrophysical sources, such as binary systems, allowing their exploration under a wide range of masses, mass ratios and physical states inaccessible otherwise and therefore opening a new window to observe the universe. The Laser Interferometry Space Antenna (LISA) mission will be a spaceborne gravitational wave observatory that is expected to be launched in 2034. The observatory will operate a near-equilateral triangle constellation of three spacecraft in formation flying around the Sun with Earth-like orbits. The observatory will establish, for the first time, a huge laser interferometer of three arms separated by 2.5 million km at pm/ p H z sensitivity, allowing detection of GW signals in the low-frequencies (mHz) regime. Using technology proven by LISA Pathfinder and GRACE-Follow on mission, the LISA metrology system will continuously operate heterodyne laser interferometers in order to measure the stretching and squeezing of space-time coupled onto their laser links as pm-level pathlength displacements and recorded as tiny µ-cycle phase fluctuations over thousands of seconds by an on-board instrument so-called Phase Measurement System (PMS) or shortly "Phasemeter”. This master thesis investigates the thermo-mechanical design of an engineering model, currently under early phases of development, for the PMS instrument onboard the LISA S/C. The mechanical enclosure has been designed following a modular approach. Each PCB will be assembled into an individual enclosure, so future upgrades in the design without affecting the entire architecture. The thermal analysis conducted so far has concluded with the feasibility of a passive thermal management system in vacuum environments, based on heat conductivity throughout the mechanical enclosure towards the instrument baseplate. In particular, the following instrument features have been included within the analysis: 1. analog signal conditioning electronics, 2. analog-to-digital conversion, and 3. FPGA core signal processing, 4. high-phase fidelity frequency synthesis and 5. frequency distribution chain, i.e., all features with the most stringent thermal requirements of the PMS-EM architecture. Although the high-power consumption demands of the instrument, the proposed thermo-mechanical design showed a suitable implementation for reliable operation of components, below maximal specified temperature ranges, allowing safe operation of the electronics over mission lifetime. As the proposed design relies only on passive conductive heat transfer methods, it is implicit a reduction of instrument complexity, avoiding complex thermal approaches based on heat pipes distributions or active control systems. Moreover, the modular approach and thermal management system enhances the integration with adjacent modules and reduce cost when assembly the instrument within the payload. In this master thesis, it has been also designed and manufactured several mechanical enclosures, together with an active thermal management system, for preliminary prototyping of analog signal acquisition electronics. These prototypes have been tested in air, setting the thermal stability requirement at the thermal reference point (TRP). Test results have verified a thermal stability requirement below 0.1 K/Hz in order to accomplish with the stringent µ-cycle phase noise performance in the mHz frequency band. Further work will test those prototypes in Vacuum conditions, consolidating thermal modelling and noise coupling as initial precursors of the PMS-EM thermally critical module developments.

  • Nisa, Yemeri
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Customer Loyalty - Does pricing matter?: A study of the managers’ perspective2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Managers have to consider different methods of keeping customers loyal to their specific company in order to secure revenue. Traditionally, pricing and pricing strategies have been good ways of acquiring and keeping customers. The purpose of this thesis is to provide a better understanding of how managers view this phenomenon today. In a sense, to analyze which importance managers place on pricing as a method of achieving customer loyalty.

    In order to obtain a greater understanding of the subject, semi-structured interviews with non-standardized questions took place. The thesis used a thematic approach to analyze the collected data. The findings and conclusions suggested that managers view price as an important factor but there are several other factors such as flexibility, customer satisfaction and competence that should be given an equal amount of attention if a company is to achieve customer loyalty.

  • Soleimanmeigouni, Iman
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Ahmadi, Alireza
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Nissen, Arne
    Trafikverket.
    Xiao, Xun
    School of Fundamental Sciences, Massey University, Palmerston North, New Zealand.
    Prediction of railway track geometry defects: a case study2019In: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980Article in journal (Refereed)
    Abstract [en]

    The aim of this study has been to develop a data-driven analytical methodology for prediction of isolated track geometry defects, based on the measurement data obtained from a field study. Within the study, a defect-based model has been proposed to identify the degradation pattern of isolated longitudinal level defects. The proposed model considered the occurrence of shock events in the degradation path. Furthermore, the effectiveness of tamping intervention in rectifying the longitudinal level defects was analysed. The results show that the linear model is an appropriate choice for modelling the degradation pattern of longitudinal level defects. In addition, a section-based model has been developed using binary logistic regression to predict the probability of occurrence of isolated defects associated with track sections. The model considered the standard deviation and kurtosis of longitudinal level as explanatory variables. It has been found that the kurtosis of the longitudinal level is a statistically significant predictor of the occurrence of isolated longitudinal level defects in a given track section. The validation results show that the proposed binary logistic regression model can be used to predict the occurrence of isolated defects in a track section.

  • Salehi, Shahin
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Machine Learning for Contact Mechanics from Surface Topography2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • Ávila Braz, Thaís
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Shrinkage Calculation in the Continuous Casting of Duplex Stainless Steel2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • Jildesten, Jacob
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Sprängsalvor i olika bergarter2019Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [en]

    The master thesis was made at Bergsskolan in Filipstad in cooperation with Skanska Industrial Solutions AB. The follow-up was made during the time period of April – June 2019. The main purpose of the thesis was to create a follow-up system that Skanska could use and develop into a real working tool in the future. The focus of the system was aimed at the most important parameters of successful blasting. Skanskas blasting records from the different opencast mines were used to create the follow-up system. SGU: s rock map of Sweden was also used to locate the different rock types in the opencast mines. The system was created in the data program Excel. The system is based on rocks versus mines, were the blasting information is connected to the mines. The follow-up system works like this: 1. Choose the type of rock you are searching for  the system will then show you all the opencast mines that operate in that kind of rock. 2. Click on the mine that you are searching for  the system will take you to that mines blasting information. 3. Choose the burst number and apply all the relevant blasting information in the right boxes. 4. Save the file  done! The result showed that the goal of the thesis was reachable. A follow-up system was created were blasting information in different rocks was shown. The system is only a prototype of how a follow-up system in different rocks can look like. If the company wishes to use the system, then it should be recreated in another data program (not Excel) that specifies on database programming.

  • Lundberg, Christoffer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    CoFramer: Ett diskussionsformat för djupa diskussioner på publika forum med låg Information Overload inspirerat av Philosophy for Children2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The focus of this essay is to develop a design concept for online public discussions with deep discussions and low information overload. The method used is Concept Driven Interaction Design (CDID) which involves constructing a design concept by applying a variety of theories in tangible interaction design. A design concept has three basic parts: a name, high-level goals and outlines generic principles. CDID includes seven steps which is used in this work:

    1.      Concept Generation – Formatted into a table that compare forum discussion (with several hypothesis) compared to discussions with the method Philosophy for Children (P4C) and other theories.

    2.      Concept Exploration – Eight distinct design aspects are identified from the comparison table.

    3.      Internal Concept Critique – The design aspects are compared to three similar discussion formats.

    4.      Design of Artifacts – Design concept version 1 is created.

    5.      External Design Critique – Interviews are conducted to explore their general experience of online discussions, investigate the hypothesis from the comparison table and to seek direct feedback on the first draft of the design concept.

    6.      Concept Revisited – Changes are made to the design concept based on the interview material and the direct feedback.

    7.      Concept Contextualization – The design concept is related to the original literature.

    The result of the study is a design concept named CoFramer. CoFramer’s generic principles are summarized and contrasted against factors identified from the interview material in this table:

    Tabell 2: CoFramer’s generic principles and interviews about online discussions.

    CoFramer’s generic principles | From interview material on forum discussion

    Organized start and ending | Discussions without clear ending

    Limited number of participants | Large number of participants

    Minimum number of participants | Large number of inactive spectators

    Explicit participants | Low information about participants

    Common conditions | Vagueness in participants conditions

    Limited information density per post | Long posts and/or fast posts

    The red thread and parallel threads | Often parallel threads

    Active facilitator | Unresolved misunderstandings

    The study indicates that CoFramer would create more structured discussions with a lower amount of information overload and less grounding cost compared what normally arise in public online discussions.

  • Pavuluri, Sri Harsha
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Development of an Automated Test Platform for Characterization and Performance Assessment of Electronic Modules in Electric Thrusters: The TESPEMET Project2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    There has been a sharp increase in the market for electric propulsion systems for small satellites in the recent years. Electric propulsion systems have become smaller, more efficient and cheaper, which made them ideal for small satellites because they have a low thrust requirement and benefit significantly from the high specific impulse (Isp) that is characteristic to electric thrusters. These thrusters are generally fabricated and tested manually and there is a low degree of automation in the process. As the demand for the thrusters increases, there is a need to improve the speed of the fabrication and testing process. The Test Platform for Electronics Modules in Electric Thrusters (TESPEMET) project at ThrustMe is an attempt to design a system that addresses this issue. The vision is to have a test platform that facilitates the testing of ThrustMe's Electric Thrusters by applying various source and load conditions, emulating events while performing instrumentation during the test process and generating a test report at the end of the test procedure. The development of such a test platform would enable and accelerate the test and qualification process of the thrusters significantly. This thesis presents the technical design of this test platform along with the results obtained, encountered problems and solutions. Future work and design changes have also been proposed based on the knowledge gained during the Research and Development process.

  • Public defence: 2019-12-05 16:29 E231, Luleå
    Hua, Jing
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Machine Elements.
    Active friction control by using CO2 and moisture2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Nowadays the demand for intelligent control of tribological interactions is strongly increasing in various applications. We often strive to minimize friction but there are also many situations where high friction is desirable. In some cases, something in between, i.e. optimum friction, is attractive. Driven by the broad application prospects, many controllable friction systems regulated with external stimuli such as solvent, pH, temperature, electric potential, and magnetic field have been designed and fabricated. When external stimuli are imposed on the smart materials, the macroscopic physicochemical properties of the materials are dramatically changed, making controllable friction behavior to become possible. However, most of these exploratory works are in nano/micro size and it’s difficult to use these incredible methods in macroscale directly due to that macroscopic laws of friction do not generally apply to nanoscale contacts. This thesis attempts to find more versatile methods of friction control and try to find the possibility to achieve friction control at macro-size.

    Firstly, since viscosity plays an important role in elastohydrodynamic lubrication (EHL) at macro-size, it is instigated if it would be possible to adjust friction by controlling viscosity in a lubricated contact. By exploiting the ability to adjust the viscosity of the switchable ionic liquids, 1,8-Diazabicyclo (5.4.0) undec-7-ene (DBU)/ glycerol mixture via the addition of CO2, the friction could be controlled in the EHL regime (Paper Ⅰ). In order to understand more about the lubricating mechanism of DBU/glycerol/CO2 mixture, the central film thickness of the lubricants as a function of the entrainment speed was investigated.

    Secondly, due to that adhesion could have influence on boundary lubrication (BL) friction at macro-size, it is investigated if it would be possible to adjust friction in a lubricated contact by controlling environmental humidity, which can alter the H-bond types, leading the change of adhesion. By exploiting the ability to adjust the environmental humidity by various saturated salt solutions, friction behavior lubricated by Choline L-Proline ([Cho][Pro]) could be modulated in a wide range of relative humidities (RH) (Paper Ⅱ).

  • Abed, Salwan Ali
    et al.
    Department of Environment, College of Science, University of Al-Qadisiyah, Iraq.
    Ewaid, Salam Hussein
    Technical Institute of Shatra, Southern Technical University, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Evaluation of Water quality in the Tigris River within Baghdad, Iraq using Multivariate Statistical Techniques2019In: Journal of Physics, Conference Series, ISSN 1742-6588, E-ISSN 1742-6596, Vol. 1294, article id 072025Article in journal (Refereed)
    Abstract [en]

    This research concentrated on the Tigris River water quality monitoring information. Some multivariate statistical techniques were applied like basic Ingredient (PC) test, discriminant analysis (DA), multiple linear regression analysis (MLRA) to evaluate important parameters affecting water quality during year 2017-2018. The study included 25 water quality parameters, viz., Temperature (T), Potential of Hydrogen (pH), Turbidity (Tur), Total Alkaline (TA), Full rigidity (TH), Calcium (Ca+2), Chloride (Cl-1), Magnesium (Mg+2), Electrical Conductivity (EC), Sulfate (SO4-2), Total Solids (TS), Suspended Solids (SS), Iron (Fe+2), Fluoride (F-1), Aluminum (Al+3), Nitrite (NO2-1), Nitrate (NO3-1), Silica (SiO2), Phosphate (PO4-3), Ammonia (NH3), Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Sodium (Na+1), and Total Dissolved Solids (TDS). Generally, all the parameters were within the standards except Tur, TA, Ca+2, EC, SO4-2. The levels of Tur and EC are of critical factors influence upon the Tigris water quality. The PCA identified six principal components responsible for 78.12% of the variation caused by the industrial, domestic, municipal and agricultural runoff pollution sources. DA results produced the eight parameters; T, BOD5, EC, Mg+2, DO, Tur, Na+1, and COD as the most significant parameters differentiating the two parts of the year (the cold and warm seasons). The result of MLRA showed that BOD5, Na+1, T, DO, and PO4-3 are the important dependable factors for predicting the COD value as an indicator of organic and nonorganic pollution. This research demonstrated success importance utilizing Multivariate statistical methods like valuable instrument of administration, control, and preserve the water of the river.

  • Humad, Abeer
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Habermehl-Cwirzen, Karin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Cwirzen, Andrzej
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Effects of fineness and chemical composition of blast furnace slag on properties of alkali-activated binder2019In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 12, no 20, article id 3447Article in journal (Refereed)
    Abstract [en]

    Abstract: The effects of fines and chemical composition of three types of ground granulated blast furnace slag (GGBFS) on various concrete properties were studied. Those studied were alkali activated by liquid sodium silicate (SS) and sodium carbonate (SC). Flowability, setting times, compressive strength, efflorescence, and carbonation resistance and shrinkage were tested. The chemical composition and microstructure of the solidified matrixes were studied by X-ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) coupled with EDX analyser. The results showed that the particle size distribution of the slags and the activator type had significantly stronger effects on all measured properties than their chemical composition. The highest compressive strength values were obtained for the finest slag, which having also the lowest MgO content. SC-activated mortar produced nearly the same compressive strength values independently of the used slag. The most intensive efflorescence and the lowest carbonation resistance developed on mortars based on slag containing 12% of MgO and the lowest fineness. The slag with the highest specific surface area and the lowest MgO content developed a homogenous microstructure, highest reaction temperature and lowest drying shrinkage. Thermogravimetric analysis indicated the presence of C-(A)-S-H, hydrotalcite HT, and carbonate like-phases in all studied mortars.

  • Danielsson, Evelina
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Vad ska glesbygdskommunerna göra med bioavfallet?: Fallstudie för Vilhelmina kommun2019Independent thesis Advanced level (professional degree), 300 HE creditsStudent thesis
    Abstract [sv]

    I denna rapport belyses vilka särskilda förutsättningar som råder i glest befolkade kommuner, och mer specifikt fjällkommuner, när det kommer till insamling av bioavfall i form av matavfall och avloppsslam. Detta görs genom en fallstudie över Vilhelmina kommun som år 2019 är en av alla de kommuner som ännu inte infört separat insamling av matavfall.

    De särskilda förutsättningar som identifierats för avfallshantering i Vilhelmina kommun, och som kan antas likna de i många andra glest befolkade fjällkommuner, är de stora avstånden, de små avfallsmängderna, det vikande befolkningsunderlaget samt att insamlingen ska fungera i hårt väder och under långa kalla vintrar med mycket snö. Även turismen och fritidshusbebyggelsen i kommunen ger upphov till utmaningar vad gäller insamlingen av bioavfall.

    I rapporten jämförs befintliga system och metoder för insamling av matavfall och avloppsslam med avseende på miljömässig hållbarhet och praktisk tillämpbarhet i en glest befolkad kommun som Vilhelmina. De system för insamling av matavfall som berörs i denna rapport är system med separata kärl, flerfackskärl, optisk sortering, underjordsbehållare, sopsug, köksavfallskvarn till VA-nät och till tank, samt en ännu ej etablerad lösning i form av torrkonservering. För insamling av slam har heltömning, deltömning och tömning med slamavvattnande fordon undersökts.

    Efter genomgång av befintliga system för insamling av matavfall konstateras att inget av de i dagsläget etablerade systemen för insamling av matavfall är direkt lämpade för en glest befolkad fjällkommun som Vilhelmina kommun. Samtliga system har fördelar men också många nackdelar, ofta relaterade till dyra investeringar och de stora avstånd som råder i glest befolkade kommuner.

    Rapporten innehåller även en undersökning av möjligheterna till mellankommunala samarbeten mellan kommunerna i Västerbottens fjäll och inland när det kommer till hantering av bioavfall. Samtliga kommuner i Västerbottens inland och fjäll konstateras ha en positiv inställning till mellankommunala samarbeten kring bioavfallshantering och möjligheterna till sådana samarbeten är goda då förutsättningar och nuvarande hantering liknar varandra i de olika kommunerna. Genom mellankommunala samarbeten kan kommunerna klara investeringar i system och metoder för insamling av bioavfall som de ensamma inte kan finansiera.

    Rapporten utgör även underlag inför framtida förändringar av nuvarande insamling i Vilhelmina kommun då den innehåller en kartläggning av avfallsflöden och avfallsmängder.