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  • 101.
    Andersson, Henrik
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Hjalmarsson, Anton
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Utveckling av Steghållare: För yrkesmän med skåpbil2008Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The task given by Thule has the purpose of develop a new ladder holder for the product line Professional. Thule is obtaining a robust, safe, and easy to handle ladder holder with an attractive look. It is desirable to be able to load the ladder from behind and make loading standing on the ground possible even on top of higher vans. The ladder holder is supposed to be suited for professionals such as craftsmen and painters. This product is designed to reduce time waste and heavy lifts. It is also desirable to withstand corrosion and meet the environmental requirements.

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  • 102.
    Andersson, Johan
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Hantering av bränsleflis: Enkätundersökning och bedömning av kvalitetsaspekter2008Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Med globalt ökat klimathot och ett ökat användande av biologiskt nedbrytbara material för att bland annat driva vår motorpark och värma våra hus kommer även ett krav på ökat produktion av utsläppsreducerande (koldioxid CO2) material så som biobränsle.

    För att kunna reducera utsläppen krävs inte bara att vi ökar produktionen av biologiskt nedbrytbart ämnen utan att dessa material har de egenskaperna som de förbränningssystem de används till optimalt kräver.

    Ett av de biologiskt nedbrytbara materialen är biobränsle, framställt av skogsavfall (grot). Dess hantering ifrån avverkningstillfället tills in- transport till förbränningen har varit kärnan i detta arbete. De två grundfrågorna som har varit själva motorn i arbetet har kretsat kring;

    o Vem äger vad i olika hanteringssteg?

    o Vem vet vad i olika hanteringssteg?

    Syftet med denna undersökning var att bland annat försöka få reda på svaren på frågorna ovan men även att väcka ett ökat intresse och förståelse kring hanteringen av biobränslet från avverkningstillfället fram till in- transport till en terminal alternativt direkt in till panncentralen.

    Undersökningen gjordes genom en enkätundersökning på Internet. Enkäten skickades ut till berörda parter i Sverige per e-post och adressaterna kunde svara direkt i datorn och skicka tillbaka enkäten utan att skriva ut den. Svaren från Skåne i söder upp till Mälardalen i norr vilket gör att man kan säga att denna undersökning gäller för södra Sverige.

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  • 103.
    Andersson, Lena
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Vänskap: En uppsats om ungdomars vänskapsrelationer2009Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den här uppsatsen vill synliggöra att vänskap är en viktig del i ungdomars vardag i skolan. Uppsatsen är baserad på intervjuer och visar hur ungdomar uppfattar sina vänskapsrelationer.

    Nyckelord: Vänskap, relationer och ungdomar.

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  • 104.
    Andersson, Magnus
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Cederholm, Anders
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Alternativa byggsystem för att minska transmissionsförlusterna på miljonprogrammets byggnader2009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose with this project is to explore and verify three renovating systems for Miljonprogrammet (common expression for

    buildings constructed during the years 1965-1975 when over a million houses where built in Sweden) to take measure to the

    largely transmission losses of these buildings. Many of the buildings from this period have similar constructions and therefore

    the same techniques can be used to renovate several of them. This project only considers the climate scale, although there

    are many more factors to concern for to efficient the buildings of Miljonprogrammet.

    This thesis presents examples of renovations carried out using two of the three renovation systems.

    The essay presents a reference house of choice on which we apply the three systems and calculate the new U-values,

    consumption of energy and the investment costs. The new U-values the building is given is matched to the values of

    recommendation for passive houses. Our reference house is a two story apartment building, located in the village of

    Lammhult, with brick facades at the ends and plaster at the long sides. One of the long sides contains balconies. The three

    systems are additional insulation, prefabricated additional insulation and replacement of the facade. We consider which

    renovation systems are best in different conditions, also considering the treatment of the tenants.

    The result of the study shows that with additional insulation and prefabricated additional insulation the buildings transmission

    losses will be major lowered. The investment cost and payoff time for the prefabricated version is much lower. If the standard

    of passive house is wanted the replacement of facade technique should be used. This method requires that the tenants move

    out during the renovation work. The investment cost for this method is significantly higher but the payoff time is equal with the

    additional insulation methods payoff time

     

     

    .

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  • 105.
    Andersson, Mattias
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Metodikförslag för bedömning av byggnaders energiprestanda2003Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    According to an EU-directive, all buildings are to be energy certified from the year 2006. The purpose is to save energy. How the energy certification will be done is not yet decided, but a few certain directions are given. One of those is that a building´s energyperformance characteristics must be determined. The energy performance characteristics are the object´s measured power supplies compared to its computer calculations (in IDA Indoor Climate Energy 3.0). Saving energy can be easy, if you instead of making lowcost energy improvements lower your demands of your indoor climate for example reduced ventilation and lowered temperature. To avoid the indoor climate to be affected negatively, tests have been made to show that the demands have been fulfilled. Calculations and data collections were made during short periods of time, and the result was evaluated considering the method´s appropriation for evaluation of a building´s energyperformance characteristics

  • 106.
    Andersson, Mikael
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Energieffektivisering av kulturhistoriska byggnader: Energi och klimat i Lekaryd kyrka2007Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete syftar till att utreda inneklimat- och energisituationen i Lekaryd kyrka. För att göra detta har klimatmätning genomförts, samt simuleringar med datorsimuleringsprogrammet IDA – Klimat och energi. Kyrkan har höga energikostnader och för att få kännedom om energiförlusternas storlek och fördelning, har en kartläggning av kyrkans energiflöden genomförts i syfte att fastställa dess energibalans. Målet är att resultaten från klimatmätningen och datorsimuleringarna ska kunna användas som underlag vid utarbetande av åtgärdsförslag för en lönsammare och ur bevarandesynpunkt skonsammare drift av Lekaryd kyrka. Kyrkan värms intermittent vilket är skonsammare för kyrkan då långvariga variationer i den relativa fuktigheten undviks. Analysen av inneklimatet i kyrkan visar att den relativa fuktigheten ligger inom ett intervall där risk för uttorkningsskador och mögeltillväxt inte bör vara överhängande. De datorsimuleringar som har genomförts, innefattar simulering av kyrkans inomhusklimat och kyrkans energibalans. Vid datorsimulering av en tung stenkyrka är det viktigt att programmet tar hänsyn till väggarnas värmetekniska egenskaper för att ett bra resultat ska erhållas. Byggnadens värmelagrande förmåga tar programmet hänsyn till, men komplikationer uppstår när noggranna värden i relativa fuktigheten önskas. Resultatet från energisimuleringen pekar på att kyrkan dras med stora energiförluster i form av transmission genom byggnadsskalet, samtidigt som det visat sig att det passiva värmetillskottet från sol och intern transmission har en betydande inverkan på kyrkans aktiva uppvärmning.

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  • 107.
    Andersson, Niklas
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Granskning av reklamationer och dess orsaker hos Sävsjö Trähus AB: Review of complaints and reasons for that at Sävsjö Trähus AB2007Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    House production is a process where high quality thinking is important in order to avoid customers complaints. The niche of Sävsjö Trähus AB (STAB) is to adapt each house as close as possible to the specific requirements of the costumer. This complicates the production process of the houses and also increases the risk of possible complaints. During 2006 STAB had complaints orresponding to approximately 3,1 millions SEK. The aim and the purpose of this study is to examine the complaints, the checkpoints and the different stages in the process of house building in order to counteract the origin of complaints and to give advise that can reduce the number of inspection remarks.

    One result of the study is a division of complaints in damages that are physically caused and problems that are caused by wrong decisions - caused of lack of communication between involved persons. In order to counteract the origin of complaints more intensive and clearer information should be exchanged among involved parties e.g. with the help of the business programme Pyramid. 3D blueprints should also be made in order to communicate what the house will look like when it is finished. This will make the customer aware of what has been decided in an early stage. Another recommendation is a change of the salesmen’s education in order to get a better overall vision of the house production (go beside a salesman, a draughtsman, production personnel and finally maybe

    also participate in a house rising). STAB should also continue to reward salesmen that achieve no remarks at the inspection. Further STAB should commit skilled installers or engage own assembly staff under STAB or under the salesman and demand that this staff makes all of the house risings. Further STAB should to subcontractors emphasize the need for improved packaging of woodwork.

  • 108.
    Andersson, Odd
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Consideration of key aspects during the implementation phase of Statistical Process Control2004Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    Manufacturing organisations of today needs to be aware of the advantages they can gain from an increased product quality. Obtain quality improvements by implementing new techniques, such as Statistical Process Control (SPC), is popular and the applications increase continuously. Even though SPC is well covered in the literature, the knowledge concerning the initiating is poor. This phase is evidently crucial and failures are commonly occurring. Identification of crucial key aspects that contributes to a successful application is often neglected due to misinterpretations.

  • 109.
    Andersson, Sofia
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Svensson, Olof
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    A model to guide a company towards a decision of whether to change the due date of work orders or not: a case study2007Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to develop a model that will guide a company towards a decision of whether to

    change the current due date of work orders or not. The model will help the company to reveal the technical and

    financial factors that will be affected and how these factors can be assessed. After accomplishing a thorough

    literature review, we found no existing practical models in this specific area. We developed a model to cover this

    gap in the existing theories. A case study approach was used to test the developed model on our case company

    Elitfönster in Lenhovda who manufactures windows. We applied our model at the processing department and the

    change concerned going from a weekly to a daily due date of work orders. The technical factors that would be

    affected by the change of the due date are; setup times, lead time and output of components. The financial

    factors that will be affected are the tied-up capital and the manning. We found that a change could not be carried

    through without a purchase of an extra plane. The model also showed that the financial benefits that the change

    generated could not surpass the costs that an extra plane would cause. Thereby, our recommendations to the

    case company are to keep the current due date of work orders until the rest of the company can handle the extra

    components that can be produced after the change.

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  • 110.
    Andersson, Sören
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Risker med karbamidskumplast- och cellplastisolering i kulturhistoriskt värdefulla byggnader2008Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Examensarbetet har genomförts på uppdrag av Länsstyrelsen i Blekinge och Ronneby Kommun och syftar på att utreda om tidigare tilläggsisolering med karbamidskumplast och polystyrencellplastkulor, på tre stycken byggnadsminnesförklarade byggnader på Ronneby Brunn i Blekinge, har medfört eventuella fuktskador. Undersökningarna av byggnaderna har utförts med ett antal valda undersökningsmetoder som var, okulär besiktning, termografering, klimatmätning, materialtest, fuktkvotsmätning elektrisk, fuktkvotsmätning med metoden vägning-torkning-vägning, samt simulerade fuktdiffusionsberäkningar. Efter att ha sammanvägt de olika undersökningsmetodernas resultat för respektive byggnad antas det att isoleringen inte utgör något hot för väggkonstruktionerna så länge de har en hög ånggenomsläpplighet och har tätt ytskikt på utsidan. Den förhöjda relativa fuktigheten som har noterats vid beräkningar av väggkonstruktionerna antas torka ut snabbt då konstruktionen har lågt ånggenomgångsmotstånd. De skador som upptäckts vid undersökningarna beror inte på byggnadernas isolering. Ett materialtest på karbamidskumplasten visar att fuktupptagningsförmågan är högre för material ifrån byggnaderna än från ett nyare material. Det innebär att om byggnaderna utsätts för inträngande vatten kan detta sugas upp kapillärt. Därför är det av vikt att den yttre tätningen som endast består av träpanel och färg har ett tätt skikt. Polystyrencellplasten antas däremot inte ha någon större kapillaritet alls. Då konstruktionerna har ett mycket begränsat värmemotstånd och vetskapen om att ogenomtänkta åtgärder kan skapa problem, bör det företas en kartläggning av byggnadernas möjlighet till att bli mer fuktsäkra och inte minst mer energieffektiva.

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  • 111.
    Andreas, Kristoffersson
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Kaneld, Rasmus
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Kvalitetssäkring av Inleveranser2009Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Through a thorough analysis of the current situation, we have highlighted differences in

    working methods for the various workshops and drew up proposals for improvements in

    combination with a practical work description that can be implemented in the company.

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  • 112.
    Andreasson, Johan
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Emissioner av flyktiga organiska föreningar från vattenburna lacker2009Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Arbetet har jämfört de emissioner som olika tjocklek på lacklagren samt olika torkningstemperaturer ger upphov till. Det konstaterades att tjocka lager ger upphov till oproportionerligt höga emissioner både på kort och framförallt på lång sikt. En högre torkningstemperatur orsakar lägre emissioner på kort sikt men lika höga eller högre på lång sikt. Inverkan från underlaget som lacken applicerades på undersöktes också och där konstaterades att ett porösare medium, i detta fall en MDF-skiva, orsaker lägre emissioner. Sannolikt pga att ämnena sugs upp av materialet. Den tredje delen bestod i att jämföra olika testkammares förmåga att registrera de sökta ämnena. Två stycken kammare med volymen 1m3 och en liten kammare med volymen 3ml användes. Det visade sig att de båda stora kamrarna visade liknande resultat om tiden efter att lacken applicerats på proverna var densamma. Den mindre visade klart lägre koncentrationer i försöksluften men omräknat till ytspecifik utsöndring var värdena jämförbara. Ämnen med hög kokpunkt var överrepresenterade i den lilla kammaren och ämnen med låg kokpunkt underrepresenterade, vilket gör att kammaren lämpar sig bäst för jämförande studier.

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  • 113.
    Andreasson, Robert
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Jansson, Pontus
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Analys av sprickdetektion vid automatisk avsyning av granvirke: med avseende på sprickors bredd, längd och djup2008Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree project aims to examine any connections between superficial cracks in timber, in terms of dimensions and characteristics, a matter insufficiently addressed by today's visual grading systems. The projects emphasis lies within the practical studies of cracks, characteristics and dimensions, within the acquired samples. In essence, the survey set out to determine superficial dimensions, depth, type and position of cracks by using a visual grading system (WoodEye), and by comparing the results by manually measuring a number of crosscutted cracks. The material used in the experiments and which formed the basis for subsequent analysis has been of such a nature that it could be equated with structural timber normally defined under the European Standard EN 14081-1.

    The project has encompassed the analysis of 568 examples of cracks consisting of 8 various types of cracks. By obtained results it has established that the greatest and smallest width is shown in resin pockets, respective side cracks, the greatest and least average height shown in sapwood cracks, respective resin pockets, and that the greatest average depth shown in cracks occurred from felling or hurricanes. From analysis of the cracks breadth and height in relation to depth no clear connection can be established.

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  • 114.
    Anna, Bladh
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Insyn och Insida2004Student paper second termStudent thesis
    Abstract [en]

    The purpose of this project time was to experiment and investigate opportunities and limits within the glass. My concept was insight an inside, with the focus on the internal pattern at the objects. With just a little colour I wanted to create an illusion of the object being smaller than it really is. The first thought was to blast an angled transparent opening. The idea then evolved to design object with a lot of transparency, still focusing on the inside. I also chose to make two graal with a little pattern where you can se into the product. Transparency in the pattern creates an interest and excitement.

  • 115.
    Anna, Karlsson
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    A new method of peptide synthesis2004Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    My task at Polypeptide Laboratories was to test a new metod of peptide synthesis. The peptide Atosiban is manufactured by using solution synthesis. But I have synthesized Atosiban intermediate by using reversed solid-phase peptide synthesis. In this new method polymer-bound reagents are used, for example Piperazinyl polystyrene. The first step of peptide synthesis is to make a polymer-bound active ester. Then a C-protected amino acid is coupled to the polymer-bound active ester. After coupling the peptide is deprotected and can then be coupled to another polymer-bound active ester of N-protected amino acid. To get longer peptide chain repeat the reactions, deprotection-activation-coupling-deprotection. The last step of the synthesis is removal of Dibenzofulvene. The different steps of synthesis and the purity of the peptide intermediates have been checked by HPLC. Atosiban intermediate have been synthesized both in presence and absence of base. At the synthesis of Atosiban intermediate in absence of base the purity was 93% and at the synthesis in presence of base the purity was 97%.

  • 116.
    Anna-Karin, Johansson
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    LE.VA: -en fundering kring konst, budskap och vardagsting2004Student paper second termStudent thesis
    Abstract [en]

    My diplomawoek is about my thoughts of how to use objects to tell or show something. Why don´t we use our everyday objects to express ourselves. Maybe we need a happy place where we don´t have to explain or defend ourselves. We want to shut our eyes for the surroundings when our problems gets to real and get to relax in our safe environment where we don´t have to have a guilty conscience because we don´t act. I also thought a lot about the human herself, about how we feel and are. It´s difficult to admit our wrongs and differences for the person and also for the community. Everything has to be perfect but is that truly good?

  • 117.
    Annika, Wallson Arneke
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Glass without glass house2004Student paper second termStudent thesis
    Abstract [en]

    My project was divided into two separate projects. In one, Paloskal, I worked with kiln cast-glass and I choose to do most of the work myself. In the other project, U-bowl, I indulged in the possibilities with float-glass and could realise my ideas with the help of Emmaboda Glasteknik. In the Paloskal project I have had the possibility to test colour, forms and thickness of the glass. Most of the time was used to learn how to kiln cast using the lost wax technique. To a great extendt I have followed advice found in the book Glass notes. With this project I have laid the foundation for something I want to continue with. I have tried float glass and stretching its limits. I wanted to bend it as much as possible to achieve a bowl feeling with a spatial rectangular shape. I also wanted to experiment with different materials against the glass. What happens if I use rubber, ironpellet, stone or sanblaster? I saw some interesting meetings. In the end I choice leather and sandblaster. During my projects I have learned a lot, by glass and about glass. My goal to experiment, try and learn, is achieved. This time has been a great time and I feel encouraged.

  • 118.
    Ardala, Tommy
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Andersson, Åsa
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Materialuppföljning i produktionen: En undersökning av materialspill2005Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    The following report will show an account concerning a material up follow from a construction project completed by Midroc Constriction in Växjö. The report will also explain how Consultec got their amounts for the wastage percent in the calculation program BidCon. The purpose of the study is to compare the calculated material quantities with the total used material quantities from the production. The study will try to show which methods Consultec used to create the wastage percent in BidCon. The method for this study includes interviews and analysis of the BidCon calculation and Midrocs invoices concerning the current construction project. The study shows many different factors that can affect the differences that occur between planed and finished result. The study also shows that it is very important to use right consumption number for different materials in the calculation. The suggested wastage percent from Consultec for the calculation program BidCon is acquired by experience from previous constructions. There are no data or any other up following that Consultec could use to create the wastage percent in BidCon. Since the wastage percent is a fraction of the production and the material costs is the interest low from the construction companies to question these suggested wastage percent from Consultec.

  • 119.
    Arvidsson, Gudrun
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    På väg mot ett nytt yrke: Yrkeslärarstudenters VFU och handledning ur ett studentperspektiv2009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Frågor om förhållandet mellan vetenskap, teori och det praktiska kunnandet diskuteras ofta i olika utbildningar. Även i yrkesutbildningar som exempelvis lärarutbildningen, är motsättningen mellan den högskoleförlagda utbildningen och yrkespraxis centrala problem. Dessa frågeställningar är viktiga att belysa och ytterligare kunskap behövs inom området för att medverka till att lärare som utbildas på ett lämpligt sätt kan integrera teori och praktik i sitt arbete.

     

    Syftet med uppsatsen var att beskriva och analysera hur de studerande på yrkeslärarutbildningen, utan tidigare erfarenhet från skolan, upplever handledningen under den verksamhetsförlagda utbildningen. Frågeställningarna handlade också om de studerande anser att handledningssamtalen har bidragit till en integrering av yrkeskunskaper, högskolans teori och skolans praktiska verksamhet.

     

    Enligt forskare har de teoretiska ämnenas anseende ökat och de praktiska inslagen i utbildningar har minskat och förlorat i status. I utredningen om lärarutbildning, SOU 1999:63 ställs krav att minska skillnaden mellan teori och praktik. Tanken är att studenterna ska förstå att teori och praktik förutsätter varandra och att lärarutbildningen ska organiseras så att det finns ett tydligt samband mellan det kommande yrket och högskoleutbildningen. Handledaren är en nyckelperson när det gäller den studerandes lärande och olika handledarrollerna får skilda konsekvenser för deras yrkesmässiga utveckling.

     

    Metoden som använts är intervjuer och forskningsansatsen är kvalitativ, där det övergripande syftet är att få reda på hur studenterna uppfattar dessa fenomen. Resultatet visar att handledningen ser olika ut, allt ifrån att man hela tiden följer sin handledare och gör likadant som han eller hon gör, till att man i stort sett arbetar själv och förväntas sköta ett lärarjobb utan hjälp. Respondenterna är upptagna med och intresserade av hur lärare arbetar i praktiken. Mycket få av respondenterna kan se kopplingar mellan den teoretiska delen av utbildningen och praktikperioderna. Kontakten mellan högskolan och VFU-platsen har varit bristfällig och det menar respondenterna har skapat mycket oklarheter.

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  • 120.
    Assarsson, Jakob
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Eskilsson, Mattias
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Arbetsberedningar och Egenkontroller i produktionen: Work preparations and quality controls in production2009Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    I byggproduktionen behövs noggranna förberedelser för att undvika störningar och kvalitetsfel. En form av styrnings- och planeringsverktyg är arbetsberedningar och egenkontroller som vi i detta examensarbete har undersökt. Syftet har varit att se hur de fungerar och att finna förbättringsmöjligheter för dem. I arbetet gjordes en intervjustudie som visade att anställda på Peab tycker att arbetsberedningarna är ett mycket bra hjälpmedel i produktionen och att användandet fungerar ganska bra i nuläget. Enligt medarbetarna finns det dock mycket som kan utvecklas och förbättras. På företaget tycker personalen även att egenkontrollerna är något bra men själva användandet fungerar inte särskilt bra ute i produktionen.

     

    För att förbättra och utöka användandet av arbetsberedningarna krävs att tjänstemännen får en ökad förståelse och vilja att använda dem. När det gäller egenkontrollerna är det däremot hantverkarnas inställning som är bekymret, de ser inte kontrollen som något viktigt utan mer som ett moment som ödslar deras tid. Studien visar att egenkontrollen, om den används på rätt sätt, kan öka hantverkarnas engagemang och få dem att ta större ansvar för det de utför.

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  • 121.
    Attila, Dioszegi
    et al.
    Jönköping University, Dept of Mechanical Engineering/Component Technology.
    Elmquist, Lennart
    Jönköping University, Dept of Mechanical Engineering/Component Technology.
    Orlenius, Jessica
    Jönköping University, Dept of Mechanical Engineering/Component Technology.
    Dugic, Izudin
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Defect Formation of Grey Cast Iron2009Conference paper (Refereed)
    Abstract [en]

    Cast iron is one of the oldest technical alloys used for creating objects. Foundrymen from the very beginning ofcasting was fighting to avoid casting defects. In the beginning a successfully performed casting was associated withwitchcraft. Cast component producers suffer yearly substantial expanses due to rejecting or repairing castings. Thepresent work will summarize research efforts to understand formation mechanisms of defects, performed incollaboration with Swedish foundries during the last years. The presented work will focus on defects, specific castingof gray iron components. Studied defects are gas porosity, shrinkage porosity and metal expansion penetration.Novell experimental set up has been developed or existing methods has been improved to study defect formationmechanisms. Today we can realize that casting without defects are possible only by approaching the defect formationmechanism with multidisciplinary science.

  • 122.
    Augustsson, Johan
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Firerose2005Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    I want to create an artefact that increases the experience and wellbeing in the room of minimalism through

  • 123.
    Augustsson, Tina
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Söderberg, Emma
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Sandgärdsgatan, Växjö: - En attraktivare gågata2006Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the outskirts of Växjö many shoppingmalls are vastly expanding which in time could pose a threat to the city centre. Växjö city is, in shoppingaspects dominated by one main street, Storgatan. To achieve a more competitive central part of the city and complex street network, a widening of the center would be preferred. Closest at hand for a widening of the city centre is the paralell pedestrian street Sandgärdsgatan, which today is thought of as a backstreet. Our project is to propose examples on how to turn Sandgärdsgatan into a more attractive pedestrian street. Research have been carried out in the form of literaturestudies, interviews and polls aswell as fieldtrips to various urban environments. The proposals we have created include everything from remodelling and general restorations to street markets and placarding. The main proposals aside from being presented in text are also visualised in drawings whilst smaller changes are only mentioned in text.

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  • 124.
    Axelsson, Therese
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Hur följs kraven på tillgänglighet vid nybyggande av bostäder?: - En studie av utvalda bostadsprojekt i tre närliggande kommuner2008Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study is to find out how housebuilding meets the demands of availability for people with some sort of disability. The rules and demands of availability are stated in Boverkets byggregler, BBR and the Swedish standard, SS 91 42 21:2006 (publ.5). The projects in this study are compared to the rules and demands of BBR and SS 91 42 21:2006 (publ.5). The rapport studies three different house projects in three different municipalities and the result shows that only three of these nine projects meet the demands of availability for disabled people.

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  • 125.
    Axén, Evelina
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Jonasson, Ida
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Bulleråtgärder vid kapsåg2006Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project is about noise reduction of a cross cut saw at ProfilGruppen Extrusions AB, Åseda. The problems with the sound level depend on the structure-borne sound that generates in the long profiles. To lower the sound level have press clamp constructions been developed which reduce and further attends have been suggested.

    Attempts and comperative measurings of the sound level have been evaluated. The results of the comperative measurings with viscoelastic plastic as damping element display certain damping. The damping can in all probability become larger using a thicker damping element.

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  • 126.
    Basic, Eldar
    et al.
    Växjö University. Växjö University, Faculty of Mathematics/Science/Technology. Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Fransson, Johan
    Växjö University. Växjö University, Faculty of Mathematics/Science/Technology. Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Omkonstruktion av friskluftsventil2009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    By design and manufacturing of prototypes, in conjunction with sound and flow measurements, we successfully increased air flow through the vent Al-db 450. The producer of this fresh air vent is Fresh AB in Gemla, Sweden. For sound testing a box was designed and manufactured.

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  • 127.
    Baudin, Anders
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Skog och Träteknik.
    Nordvall, Hans-Olof
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Skog och Träteknik.
    Socio-economic Effects of a Bio-DME Plant in Växjö2008Report (Other academic)
  • 128.
    Bayley, Peter
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Mätning av produktionstiden vid prefabricerade hus: En tidsstudie vid Sävsjö Trähus AB2007Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Price-setting of a house includes production-cost and the production-cost is a substanial part of the total price. In production-cost are material, write-offs and salaries included. The last mentioned factor is the one that is most difficult to determine since the house-sizes and architectures never are the same. The person responsible for tender and making deals are today using factors of manufacturing which are based upon many years of experience and where the measurement is either h/m2 or h/pc depending on which factor one uses. The total covering-costs is good totally, but one does not know whether the proportions between different house-types is accurate since it constantly circulates multiple different houses in production. In this examination-work has multiple time-studies been made to research the factors of manufacturing and the proportion of them. The production-flow of the factory is controlled of the manufacturing of outer-walls and therefore the studies narrowed down to measure the stations that are assembling these. The results of the time-study showed tendencies that outer-walls made in the line and gables made at the turning-table have a factor that is high in the present system. Windows that was installed loose in a partition and windows that were studded in windowsill were also measured. Both these factors resulted in a low factor comparing to the presence.During the time-study, that lasted four weeks of time, was even the production-process researched and resulted in suggestions for changes that could increase efficiency, quality and security in the factory. One of the suggestions that could result in more efficiency was dividing the workload more efficiently in production of prefabricated houses.

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  • 129.
    Bengtsson, Charlotte
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Byggteknik.
    Serrano, Erik
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Fonselius, Mikael
    Riipola, Kirsti
    Conformity assessment for machine graded timber by using output control2008Report (Other academic)
    Abstract [en]

    In the Nordic countries machine strength grading of structural timber is becoming increasingly important. A new standard, EN 14081, which allows CE-marking of strength graded structural timber was recently accepted. This standard allows both machine

    control and output control as methods for controlling the graded timber. Machine control is most commonly used in Europe. The project reported here deals with output control. This method is commonly used in for example USA.

    Theoretical studies carried out within this project show that applying output control gives higher yield, especially in high strength classes. A document describing the implementation of the output control procedure is written and given in Appendix 1 of this report.

  • 130.
    Bengtsson, Malin
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Doweyko, Gosia
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Fönsterglas: vilka, var och varför?2006Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [ru]

    På dagens fönsterglasmarknad har produkter med samma funktioner och utseende fått olika namn. Detta är förvirrande och gör det svårt för en person som ska beställa fönsterglas att jämföra olika tillverkares produkter med varandra. Rapporten är tänkt som en översikt på de olika fönsterglasen som finns på marknaden idag och även på sådant som kan bli aktuellt i framtiden. Den berör också sådant som kan vara av värde att veta vid användning av fönsterglas. Målgruppen är alla som kan tänkas ha intresse i ämnet - alltifrån hobbybyggaren till fackmän i byggbranschen. Informationen är sammanställd från böcker, broschyrer, internet och experter på området fönsterglas.

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  • 131.
    Bengtsson, Martin
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Johansson, Daniel
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    A model for TPM implementation in SMEs2004Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    Nowadays more and more companies start to see advantages with Total Productive Maintenance (TPM). It is important for the manufacturer to work with continuous improvements in the whole company so one can stay competitive in the market. Since customer demands higher quality, lower price and deliveries in time it is important to utilize the equipment in the best possible way.

  • 132. Bengtsson, Sune
    et al.
    Brandin, Jan
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Einvall, Jessica
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Sanati, Mehri
    Production of syngas by thermochemical conversion of lignocelluloses biomass2007In: Italic4, Science & Technology of biomasses: advances and challenges, 2007, p. 125-128Conference paper (Refereed)
  • 133.
    Berggren, Karin
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Östman, Helene
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Tidiga skeden i byggprocessen: - en studie av några utvalda projekt2003Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    The building process today is very extensive and complex with a number of different actors and people involved. The last years development has led to a shortening of project times, which mosts likely has had a great influence in how the contractors handle their projects. The purpose of this examinatin report has been to document how the companies handle a project from the time just before an inquiry is handed in until the constsrucion starts. This is what we have defined as "the early stage in the building process". The report also includes a description of how the building process works. A limited number of projects have been studied. We have also used an inquiry, which has been answered by all ot fhose who were asked to. The answers from both the interview and the inquiry has given us a picture of how the building process within the companies work during "the early stages". A lot of lack of quality in the building process is due to the insufficient time planning and communication. The decisions in the early stages of the building process are often those in power. All the important decisions are made in the beginning of a project and the project is then still easy to affect. There are, despite this, no greater chenges in the early stages of the building process. To solve this problem we need more cooperation in the early stages and also a better communication.

  • 134.
    Bergquist, Martin
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Dzanic, Nermin
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Dämpning av fläktljud i diskmaskin2007Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This dissertation examines acoustic research of a disinfecting dishwasher type Getinge 8666/8668. The research has been performed in collaboration with Getinge Desinfection AB, a world wide known manufacturer of disinfecting equipment for healthcare, located in Växjö, Sweden. We have examined how to reduce noise from the dishwasher with simple measures. Measurements have been performed during the drying program of the machine. The drying fans are the dominating sources of sound, and the sound is air bourn. A systematic method by reducing the sound step by step shows that the major ways of sound is through the ceiling and through the floor. There is also a minor noise leakage through the gaps in the walls of the dishwasher. By isolating the ceiling, the floor and the gaps in the walls, it is possible to reduce the noise with totally 5.9 dB. With more production adapted solutions, in shape of an isolated floor base and a more efficient fan cover, it is possible to reduce the noise with as much as 3.6 dB. This dissertation is thought to be used as a basis for further acoustic research at Getinge Desinfection AB.

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  • 135.
    Bergström, M
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Blom, Åsa
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Thörnqvist, Thomas
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Uttorkning av vindfällda träd2007Report (Other academic)
  • 136.
    Bergström, Magdalena
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Nihlén, Anna
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Konstruktion av pallnedstaplingsmaskin: för Volvo Articulated Haulers AB2005Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    This diploma work was carried out with the help of discussions made with the staff at the company, but also with the help of necessary measurements and studies. Beside this, calculations were made in order to dimension the machine. The result of this diploma work is a design. This design can handle piles up to 2.5 meters high, existing of different pallet models with different number of collars. The machine was designed to be able to stand up to 15 metric ton and to be able to fit the existing conveyor belt.

  • 137.
    Bergström, Mikael
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Blom, Åsa
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Thörnqvist, Thomas
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Durability and Moisture Dynamics of Norway spruce (Picea abies) heartwood and sapwood2005In: Proceedings of the Woodframe Housing Durability and Disaster Issues Conference: organized by the Forest Products Society, 2005Conference paper (Other academic)
  • 138.
    Bergström, Mikael
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Thörnqvist, Thomas
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Dolda fel i stormskadat virke2007Report (Other academic)
  • 139.
    Bergström, Mikael
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Thörnqvist, Thomas
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Hur länge klarar sig stormfällt virke mot svamp- och insektsangrepp: Tema: Efter stormen2005Report (Other (popular science, discussion, etc.))
  • 140.
    Berling, Peter
    et al.
    Lund University.
    Kaj, Rosling
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    The Effects of Financial Risks on Inventory Policy2005In: Management science, ISSN 0025-1909, E-ISSN 1526-5501, Vol. 51, no 12, p. 1804-1816Article in journal (Refereed)
    Abstract [en]

    The effect of financial risks on (R, Q) inventory policies is analyzed in a real options framework. Simple adjustments of the usual formulas for R and Q are suggested and tested. Stochastic demand and purchase costs are considered, both with known systematic (business-cycle-related) risk.

    The systematic risk of stochastic demand has typically a negligible effect on the optimal values of R and Q, although an improvement may be achieved by a simple adjustment of R.

    The systematic risk of the purchase price, c, has a significant effect on R and Q. The capital holding cost should be estimated as r · c, where r is the sum of the risk-free interest rate, the expected price decrease, and the risk premium associated with the systematic risk of c.

    For goods quoted on commodity exchanges, r may be estimated directly from the prices on forward contracts. Its size (and sign) varies considerably for different commodities.

  • 141.
    Besirevic, Vedran
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Linder båtkoncept 20102007Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Projektet behandlar produktutveckling av Linders befintliga

    båtmodell Sportsman 400 med avseende på interiörutformningen

    som ska svara mot den framtida båtägarens krav och behov.

    Den framtida båtägaren består av två olika typer av individer

    som kan beskrivas som ”den äventyrliga individualisten”

    och ”den sociala traditionalisten”, som var och en har

    olika uppfattningar kring begreppet komfort.

  • 142.
    Biström, Mikael
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Fortune Teller: En Musikvideo2005Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    Is the music videos of today advertisement or are there other values to be appreciated in this artform?

  • 143.
    Bjarnason, Bjarni
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Datorstött lärande på gymnasieskolan inom naturvetenskapliga ämnen: med speciell betoning på kemididaktiken.2006Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Elever upplever allt som oftast svårigheter med den naturvetenskapliga undervisningen som ofta upplevs som abstrakt och overklig. De förklaringsmodeller som har beskrivits kring detta är att eleverna har svårigheter med att växla mellan makro (det man ser med ögat) och mikro (molekylär värld). I flera publikationer har man kunnat visa att för att nå en bred publik bör man aktivera så många sinnen som möjligt vilket är det som jag tar fasta på i detta arbete. Datormedierad multimedia framställning i undervisningen har, i publikationer, visat sig kunna kan skapa en bättre förståelse hos elever i kemi. Framförallt är det datorgenererad media framställning som simultant kan presenterar kemiska förlopp med olika representationer som har visat sig ge bra resultat. I denna studie har man kunnat visa att elever är mycket positiva till denna typ av framställning där man kan utföra experiment och se animeringar. De menar också själva att detta underlättar förståelsen av den molekylära världen. Genom att studera fall och kontroll kunde man även i denna studie visa på vissa skillnader i elevers kunskaper. De elever som fick möjlighet att studera animeringar och göra virtuella laborationer hade något bättre resultat än de som inte fick denna möjlighet.

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  • 144.
    Bjuvenius, Stefan
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Lägerverksamhet på gymnasiet        : - En studie av elevernas upplevelse av läger.2009Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
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  • 145.
    Björk, Tomas
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    En undersökning om möjligheterna att använda återanvändningsbara pallband till enhetslaster omlastade till träpallar.2007Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    An investigation of the possibility to use reusable strapping and the economic conditions for this. Going trough what exist on the market. Calculation of the forces that the unit load can expose the strapping for. Developing of own suggestions for reusable strapping with quick buckle and strapping on three sides. A short look at the positive and negative effects that comes from a change from today’s strapping with PP-strap to a reusable strapping.

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  • 146.
    Blissing, Anna
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Tillgänglighet vid entréer: Inriktning på fysiska hinder2004Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    The diploma work considers the physical obstacles at entrances in Växjö centre. This because it's important that all places here becomes accessible for people whit various disabilities. The work aims to show which physical obstacles that are the most frequent. To get an idea of which these are an inventory of 81 entrances along both sides of Storgatan was made. The work also gives suggestions on howthese obstacles could be removed.

  • 147.
    Blom, Åsa
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Svenskt barrvirke: Beständighet och fuktegenskaper ovan mark.2006Report (Other academic)
  • 148.
    Blom, Åsa
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Bergström, Mikael
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Above Ground Durability of Swedish Softwood2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis describes aspects of durability of Swedish softwood in above ground applications. The thesis consists of a summary of nine papers, which all aim to explain the existing variation in above ground microbial durability and moisture sensitivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris). The methods used were two field tests, one accelerated durability test, and three water permeability tests.

    The main conclusions made in the study were that Norway spruce sapwood is more susceptible to discolouring fungi than heartwood. With respect to Scots pine, the only important factor for its natural durability above ground was whether the samples consisted of heartwood or of sapwood. There was also no systematic variation between pine heartwood from different stand origins in above ground conditions. Origin had no influence on durability in practice for neither spruce nor pine. Furthermore, in contradiction with traditional thinking, annual ring width and density had no influence on durability in any of the tests.

    The material came from two different samplings. The ‘old’ material was sampled in the beginning of the 1980s and consisted of Scots pine and Norway spruce from three different origins: the north, the central area, and the south of Sweden. The material was subjected to different handling conditions and surface and end-grain treatments. The ‘old’ material was used in a large above ground field test, carried out between 1985 and 1994. Unfortunately, the spruce sapwood and heartwood was not separated in this field test.

    In the field trial with the ‘old’ material, the most important factor for the durability of Norway spruce was the samples’ surface- and end-grain treatment. It was also observed that untreated spruce showed better durability than samples that were painted but without proper end-grain treatment. Samples originating from one of the stands were more sensitive towards air-drying than samples from the other two, which was reflected in a higher average moisture content and mass loss for the untreated samples. With respect to Scots pine, the most important factor was whether the sample consisted of heartwood or of sapwood. The heartwood samples were durable irrespective of their previous treatment. The Scots pine sapwood samples, on the other hand, had a very fluctuating moisture content if they were not surface- and end-painted. This was also reflected in higher mass losses in these samples. Even when properly surface- and end grain treated, the sapwood samples did not perform as well as the heartwood samples.

    The ‘new’ material consisted of Scots pine taken from six different stands, and Norway spruce from five different stands, all from areas in southern Sweden. The sampling was performed in order to achieve a large variation in wood properties. Thus, logs from areas with different climate and growth conditions were collected. This material was used for laboratory tests, and also for the second field test, which was evaluated after a test period of two years.

    In the second field test untreated Scots pine and Norway spruce samples from the ‘new’ material were investigated. Effects of origin and different tree diameters were examined. Furthermore, Scots pine was separated to heartwood and sapwood, and Norway spruce to mature and juvenile wood. The Norway spruce samples were sawn with vertical or horizontal annual rings. For the Norway spruce in the second field test, vertical annual rings were shown to be very beneficial for avoiding crack formation, while samples with horizontal annual rings displayed a large number of cracks. Despite this, the larger number of cracks did not result in a higher moisture content or more fungal discoloration. Juvenile wood had a slightly higher average discolouring fungal growth grading than the other spruce samples. For Scots pine, the only factor of importance was whether the samples consisted of heartwood or of sapwood. Annual ring width, density and origin had no significant effect on either fungal growth or moisture uptake. This observation held for both Norway spruce samples and Scots pine samples.

    An accelerated test was run in order to investigate Norway spruce sapwood and heartwood with respect to their differences in durability towards discolouring fungi and moisture uptake. The Mycologg method was used to accelerate fungal growth during a number of forced moisture cycles. The results showed that sapwood was much more sensitive to discolouring fungi than heartwood. Sapwood also recorded a higher average moisture content than heartwood. The differences that were observed between the types of samples were not due to annual ring width, density or origin.

    It was observed that Norway spruce sapwood samples and heartwood samples showed differences in liquid water permeability. This observation was made especially evident in a droplet absorption test. Water droplets were absorbed much faster on the sapwood samples in comparison with the heartwood samples. This higher affinity to water suggested that a sapwood surface would reach a higher moisture content than a heartwood surface. This observation provides a major explanation of why the sapwood samples showed poorer durability towards discolouring fungi in the Mycologg trials.

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  • 149.
    Blom, Åsa
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Bergström, Mikael
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Mycologg – a new accelerated test method for wood durability above ground.2005In: Wood Science and Technology, Vol. 39, p. 663-673Article in journal (Refereed)
  • 150.
    Blom, Åsa
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Bergström, Mikael
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Untreated Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) wood-panels exposed out of ground contact in Sweden for two years.2005In: Holz als Roh- und Werkstoff, Vol. 64, p. 53-61Article in journal (Refereed)
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