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  • 151.
    Andersson, Marcus
    Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering. Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Förändring av layout och materialflöde i färdigvarulager hos AnVa Polytech AB2017Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The aim for this work has been to develop a new layout in the finished goods stock at AnVa Polytech AB in Sunne, Sweden. In this new layout the target was a single-order-flow using a roller conveyor. In the current situation there are two employees working on two different orders at the same time.

    The objective of the work was to create a better working environment, better flow of material, minimize the numbers of unnecessary transports and to minimize the risk of disturbance.

    By carrying out a number of observation of activities and drawing spaghetti charts over the workers movements during an compilation during a couple of weeks, you could see on what activity and where the workers spend the most time and see where there were most unnecessary movements. The observation of activities made clear that it was on compilation and movement the worker spend the most time. The spaghetti chart showed that the worker made a lot of small, unnecessary movements when going in and out of the forklift for different activities. Those activities were when they had to; print labels and flags to put on the compiled order, repacking or filling a box of material and wrap or string an order.

    The design of the roller conveyor was made through a discussion with the supervisors at AnVa Polytech AB to find a solution that would shorten the length of the conveyor and create a smooth flow of material. The two machines that would be a part of the conveyor were placed right next to each other to minimize the length and avoid unnecessary transportation. The roller conveyor was also set to work as an interim storage. It was mad longer in the beginning and in the end of the roller conveyor to ease the stress for the employee working at the conveyor.

    The new layout of the storage was made using a method of concept choice. The first part of the method was creating a number of concepts. The second part of the method was based of using two different matrices, one called elimination matrix and the second one relative decision matrix.

    In the elimination matrix the different concept was put against each other comparing criterias. The base value of each criteria was set by the current layout of the storage. The ones with the best results proceeded to the relative decision matrix.

    The relative decision matrix puts the best concepts from previous matrix against each other but with more in depth criteria. The one with the best result was the one being continued on.

    The chosen layout was a configured version of the best concept from the matrices. This layout saved lots of space on the floor to create a safe working environment, good and a good flow of material. The storage shelves were placed to create a smooth flow for the truck without being disturbed by pedestrians from other parts of the facility moving in the storage. The roller conveyor was placed to facilitate the communication between the two workers in the storage to avoid any kind misunderstanding while compiling an order.

    A measured drawing was created of the layout to make it easy to see were all the important parts in the storage were being placed to create the layout.

  • 152.
    Andersson, Marcus
    et al.
    Karlstad University.
    Arvidsson Nordgård, Elias
    Karlstad University.
    Statisk ljudtryckssensor: Att konstruera ett mobilt mätsystem för vapenindustrin2015Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Bofors Test Center has during recent years gained increased critiques concerning loud sound levels associated with their daily activities, which mainly comprises test firing of newly developed weapons and ammunition. The noise that occurs sometimes result in discomfort for the public, with complaints as a consequence. In the long run this could lead to the county administrative board establishing limits or demanding the company to control the noise levels they cause. If the company could prevent the authority’s eventual demands by registering the sound levels overtime, then this will be seen as a guarantee for the company to continue with the same activities they do today.The purpose with this thesis is to produce a mobile unit to measure and log all values that exceed the threshold set at 80 dBC. Bofors Test Center should later have the opportunity to produce more copies of this unit to be placed permanently or mobile within Bofors Test Centers neighboring if desired.To achieve this we had to investigate controller, power supply, sensor and logging. Communication between the unit and a server was excluded since the project would become too big.The final product is a unit that saves its measured peak-values on a USB-stick and types out the highest and latest measured value on a display.

  • 153.
    Andersson, Markus
    Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Materialflödesanalys och layoutförslag Volvo Penta AB: Avdelning: Montering D4/D6 och D32013Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Volvo Penta i Vara tillverkar diselmotorer för marint bruk. Nya materialfilosofier har ändrat förutsättningarna för materialflödet ute i produktionen. Även ökade krav på miljö och säkerhet gör att Volvo Penta i Vara vill se över sin layout för att kunna effektivisera de interna transporterna och därmed göra fabriken säkrare.

    Detta arbete avser monteringen på Volvo Penta och har skett parallellt med Marcus Nordberg som tittat på bearbetningen och målning/pack.

    Syftet med arbetet är att ta fram ett förslag på en ny layout som kan gynna fabriken med hänsyn till de nya förutsättningarna som gäller för materialflödena och bidra till en renare och säkrare miljö. Genom att kartlägga materialflödet i fabriken kan en nulägesbeskrivning sammanställas och med denna kan en ny layout tas fram. En jämförelse med nuläget ger faktaunderlag för att visa vad en ny layout kan medföra.

    En frekvensanalys gjordes på de artiklar som i dag körs av gaffeltruckar för att skapa en uppfattning om materialflödet. Frekvensstudion kompletterades med layoutdiagram för att kunna mäta upp sträckan artiklarna färdas i genomsnitt per dag. En enklare simulering på fabrikens interna transporter gjordes i syfte att visa Volvo Penta användningen av en simulering. Denna gav även en bättre uppfattning om truckkörningen i form av avstånd. Nulägesbeskrivningen sammanställdes och brister identifierades innan arbetet med den nya layouten började.

    Sammanställningen av nulägesbeskrivningen visade att dagens materialflöde var väldigt rörigt och gick genom produktionen där rörelsen av människor är som störst. Lösnigen som togs fram på detta var att lägga till ytterligare en godsmottagning på motsatt sida. Andra brister som identifieras är materialhanteringen av tillförelsematerial till monteringen och åtkomligheten till grunddelen för truckar. Alternativa förslag på materialhanteringen och vad de ger för fördelar togs fram. En ny layout föreslås på grunddelen för att öka åtkomligheten.

    Jämförelsen med den nya layouten visade att den totala sträckan transporter kunde reduceras med 4,1 km vilket motsvarar en minskning på 30 %. Tidsminskningen på ett skift med dagens takt skulle bli 30 min.

    Den nya layouten med den nya godsmottagningen skulle bidra till effektivisering av de interna transporterna och minska dessa genom produktionen kraftigt vilket skulle ge en säkrare miljö. 

  • 154.
    Andersson, Martin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Torkning integrerat med kraftvärmeverk: Påverkan av energibalanser i torksystem vid integrering till kraftvärmeverk2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    I Sveg finns ett pneumatiskt torksystem. Systemet har sedan 1989 torkat torv till briketter men har på senare tid torkat både trä och torv för produktion av bränsle i form av pellets och briketter. Idag består anläggningen av två symmetriska torklinjer. I torklinjerna används en värmepumpkrets för återvinning av råvaruånga. I värmepumpkretsen används en kompressor driven av inköpt elenergi. Planerna är att integrera en av linjernas nuvarande torkprocess till ett kraftvärmeverk genom installation av ångpanna med bränslet torv och således producera el istället för att köpa el. Integrationen till kraftvärmeverket ger torklinjens värmepumpkrets ett nytt utseende. Kompressorn tas bort i utvald torklinje och ersätts av två lågtrycksturbiner. Det nya utseendet av värmepumpkretsen kommer innebära ett samspel mellan torkning och kraftvärmeverk. I värmepumpkretsen används olika ångflöden beroende av vilket råvarumaterial som torkas. Därför beräknades och användes olika ångflöden beroende av olika fukthalter och inmatningar i torksystemet för att se hur el- och fjärrvärmeproduktionen i kraftvärmeverket påverkades. Samtidigt jämfördes nuvarande torksystem med torksystem integrerat med kraftvärmeverk ur ett energiperspektiv genom förändring av el, fjärrvärmeproduktion och biobränsle.

    Fjärrvärmeproduktionen i kraftvärmeverket ökade vid ångflödena 31,0 ton/h och 24,0 ton/h ”till kompressor” men på grund av större beräkningsosäkerhet bortsågs dessa. Detta gav en varierad sammanlagd fjärrvärmeproduktion av systemen mellan 23,0-23,8 MW respektive 22,0-22,5 MW vid torkning av torv respektive trä (bortseende av torvscenario 1 vid fukthalten 65 %). En fjärrvärmeproduktion i den storleken, jämfört med Svegs fjärrvärmebehov, kan sägas vara för stort. En stor problematik blir därför vad all spillvärme ska användas till, framförallt på sommaren.

    Vid integrering till kraftvärmeverk minskade ”bränsle” medan ”fjärrvärme” och ”el” ökade. Beroende av vilket råvarumaterial som torkades gav en integrering ett större resultat för ”el” men mindre ”fjärrvärme” och ”bränsle” vid torkning av trä. Därför rekommenderas torkning av trä eftersom större resultat av ”el” minskar inköpt elenergi samt mindre ”fjärrvärme” resulterar till mindre spillvärme.

    Vid beräkningarna användes Simulink, ett verktyg för grafisk lösning av differentialekvationer, som ingår i programvaran MATLAB från Mathworks. I Simulink formerades olika ekvationer i statiska beräkningsmodeller för beräkning av energibalanserna i nuvarande torksystem och torksystem integrerat med kraftvärmeverk. Energibalanserna i nuvarande torksystem undersökte svårplacerade effektförluster samt genom olika energibalanskontroller kontrollerade och bedömde trovärdigheten i beräkningsmodellen. Resultaten för energibalanskontrollerna kallades ”beräkningsosäkerhet” vilket var en av flera parametrar som framlade bevis för ett variabelberoende, känsligt, komplext och svårtydande torksystem där övriga effektförluster var svåra att placera. Ett mer korrekt resultat av nuvarande system kan därför möjligtvis uppnås vid användande av en dynamisk istället för statisk modell samt användande enbart av mätdata istället för dimensionerande värden och således göra effektförlusterna lättare att placera.

  • 155.
    Andersson, Martin
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Social and Psychological Studies.
    "Who am I now?" Sense of Gender and Place in Digital Gameplay: Affective Dimensions of gameplay in XCOM: Enemy Within2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this essay I analyze the ways in which gender and space are shaped and made sense of through digital gameplay. Specifically in the turn based strategy game XCOM: Enemy Within for the MacBook Air with a computer mouse as the primary input device. Using a mixed methods approach consisting of gameplay sessions of XCOM and qualitative interviews with two players regarding their gameplay I argue that earlier research on space within game studies has overlooked the ways in which the shaping of space in gameplay is also gendered. Developing a theoretical framework influenced by gender studies, critical theory, affect theory, assemblage theories of space, and game theory, I argue for how the shaping of space and gender in game-play is interdependent. This in that the shaping of space and gender in digital gameplay is in constant relation and tension with societal norms and the affective capacities of bodies and digital games. In conclusion, I reflect on the possibilities to develop more empirical research based on the the theoretical framework explored in the essay.

  • 156.
    Andersson, Mattias
    Karlstad University, Division for Engineering Sciences, Physics and Mathematics.
    Kylskåpsinredning: Praktiska funktioner2008Independent thesis Basic level (professional degree), 15 points / 22,5 hpStudent thesis
  • 157.
    ANDERSSON, MONICA
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies (from 2013).
    ”Barnens intresse styr över hur vi arbetar med naturvetenskap och teknik i förskolan”: En studie av förskollärarens sätt att beskriva hur de kan tillvarata och utveckla de yngsta barnens, 1–3 år, intresse för ämnena fysik och teknik2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this study is to gain an in-depth understanding of how a preschool can work with the subjects of science and technology in a well-thought-out way. The purpose of the study is also to provide more knowledge about which different ways pedagogues can use and develop the children's interest in technology and physics. The study is qualitative and has been carried out by studying documentation from social media published by the preschool. The documentation has since been a basis for the semi-structured interviews that were conducted. To reach the result, the phenomenographic analysis model has been used.

    The result shows that the three teachers interviewed at this preschool see no obstacles to working with the subjects of science and technology with the youngest children, 1-3 years, even though they lack a formal in-depth education in the subjects. The preschool teachers only see opportunities. To create the best conditions for teaching science and technology the preschool has worked out a community of practice inspired by Reggio Emilia.

  • 158.
    Andersson, Monica
    Karlstad University, Faculty of Technology and Science.
    Bygga hus i traditionell härjedalsstil2008Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 159.
    Andersson, Natalie
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies (from 2013).
    Titta där, en bro till: Vad uttrycker barn i ålder 2,5-3 år om broar?2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The intention with this study is to look into what and how children at the age of two and a half and three years old expresses about bridges. The study is qualitative and have been completed with unstructured pre- and after interveiews and participant observation with two different groups with in total four children that have been introduced to different materials representing bridges. The difference between the materials is that the first group in the pre interview have been introduced to a toy representing a bridge that the children know from before and a book with the three Billy goats, unlike the second group that had no connection to a story. In the study the four children have been in two different groups. All children in age two and a half to three years old have been completed a pree interview before they went to town to search for bridges and a following interview after that. The results are based on all of the occasions. The children expressed their understanding of the bridge`s function about crossing over to reach the other side. The fence is needed to not roll over and can be a protection. The bridge also often have a stairs so you can go up on the bridge. The results shows that the children talks about bridges through for them known stories and games regardless if they did get a story presented or not. Through the childrens telling and playing, the study shows that the children possess understanding of the function of the bridge because of their explanations about how you need to walk over the bridge to cross over to the other side and not get wet. The children also talks about the different parts like fence and stairs and their function to the bridge.

  • 160. Andersson, Niclas
    et al.
    Germgård, Ulf
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering.
    Johansson, Kristina
    Ljungqvist, Carl-Henrik
    Thuvander, Fredrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Determining the strain to failure for constrained pulp fibres by means of single-fibre2002In: Appita Journal, Vol. vol 55 no 3Article in journal (Refereed)
  • 161. Andersson, Niclas
    et al.
    Germgård, Ulf
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering.
    Johansson, Kristina
    Ljungqvist, Carl-Henrik
    Thuvander, Fredrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Determining the strain to failure for constrained pulp fibres by means of single-fibre fragmentation2002In: Appita Journal 55(2002)3, 224-229Article in journal (Refereed)
  • 162.
    Andersson, Niclas
    et al.
    BTG Process Solutions, Sweden.
    Wilke, Caroline
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013). BTG Process Solutions, Sweden.
    Akhlesh, Mathur
    BTG Process Solutions, Singapore.
    Smith, Dan
    BTG Process Solutions, USA.
    Germgård, Ulf
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Measurement of Dissolved Lignin, and its Impact in Fiberline Unit Operations2017Conference paper (Refereed)
  • 163.
    Andersson, Niclas
    et al.
    BTG Instruments.
    Wilke, Caroline
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences. BTG Instruments.
    Biazzo, Tom
    BTG Americas Inc.
    Van Fleet, Rick
    BTG Americas Inc..
    Germgård, Ulf
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Beder-Miller, Sandra
    BTG Americas Inc..
    Is Conductivity the Best Measurement of Bleach Plant Carryover?2015In: Pulp & paper Canada, ISSN 0316-4004, p. 1-6Article in journal (Refereed)
  • 164. Andersson, Niclas
    et al.
    Wilson, David
    Germgård, Ulf
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering.
    An improved kinetic model structure for softwood kraft cooking2003In: Nordic Pulp and Paper Research Journal, Vol. vol 18 no 2Article in journal (Refereed)
  • 165. Andersson, Niclas
    et al.
    Wilson, David
    Germgård, Ulf
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering.
    Model based kraft cooking optimisation2003In: Nordic Pulp and Paper Research Journal, Vol. vol 18 no 4Article in journal (Refereed)
  • 166. Andersson, Niclas
    et al.
    Wilson, David
    Germgård, Ulf
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering.
    Using validated continuous kraft digester models for profile optimisation2002Conference paper (Refereed)
  • 167. Andersson, Niclas
    et al.
    Wilson, David
    Germgård, Ulf
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering.
    Validating continuous kraft digester kinetic models with online NIR measurements2002Conference paper (Refereed)
  • 168. Andersson, Niclas
    et al.
    Wilson, David
    Germgård, Ulf
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering.
    Lindström, Tomas
    Organic matter content in black liquor inside and outside chips during kraft cooking2001In: Paperi ja Puu, Vol. vol 83 no 7Article in journal (Refereed)
  • 169.
    Andersson, Nina
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies (from 2013).
    Digitaliseringen i förskolan: Pedagogernas uppfattning av hur digital teknik används i förskolans verksamhet2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 170.
    Andersson Nyrén, Martina
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School.
    Pilotstudier avanvändargränssnitt till app för smärtpatienter2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Experio Lab i Landstinget i Värmland, Karolinska Institutet och Kungliga TekniskaHögskolan håller i dag på med att utveckla en digital tjänst i form av en app försmärtpatienter. Målet är att genom en digital tjänst kunna lära sig mer om hur patienter kankartlägga sina besvär inför ett möte med sjukvården.

    Uppsatsen syftar till att inför kommande användbarhetstester på riktiga patienterundersöka hur väl prototypen fungerar när det kommer till gränssnittet och ge förslag somskulle kunna förbättra appen inför de kommande användbarhetstesterna.

    Undersökningen genomfördes i två steg: Först testades appen som en pappersprototyp.Därefter genomfördes användbarhetstester med hjälp av studenter och experter inomtjänstedesign på en ipad-platta, där både intervjuer och observationer gjordes. Resultatetvisade att flera av testpersonerna hade samma sorts svårigheter när det kom till att interageramed appen. Svårast var att rita sina besvär på besvärsteckningen samt att veta var i processenman befann sig. Efter genomförande av studien uppgav de flesta testpersonerna att de skullerekommendera appen till någon de kände. Majoriteten såg även behov av att appensanvändargränssnitt blir tydligare för användaren.

  • 171.
    Andersson, Olle
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Bergstrand, Ann-Charlott
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Höjdbestämningsmetoder vid upprättande av nybyggnadskartor: Jämförelse mellan nätverks-RTK och trigonometrisk höjdmätning2016Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    Levelling and trigonometric height measurements are the methods that are mostly used today for height determination, as the standard error with these methods is in the magnitude of millimeters, as long as the view length is less than 50 m.

    When creating a new construction map the requirement on standard error differ from 1 (Fredriksson, 2011) to 10 cm (www.arvidsjaur.se) depending on which municipality it concerns.

    When using network RTK for measuring, the accuracy in height can fall below 3 cm when the conditions are optimal. The purpose of this paper is to investigate if network RTK can be used as an alternative to determinate height when accuracy under 10 cm is requested.

    Five points at locations with different conditions for accuracy got their height determined with the three methods mentioned above. Positional accuracy was formed for each point and method. The result from levelling was used as reference for the calculations. To compare the result with the requirements extended standard uncertainty, 2covering 95 %, was used. The result from trigonometric height measurement shows a position accuracy of 4 mm. From the network RTK, the points that were positioned without interference got a positional accuracy of 3.3 to 5.5 cm, while the points that were influenced by their environment, multipath interference and obstructions, got a positional accuracy of 123.3 cm and 234.4 cm. Positional accuracy of this method became 127.4 cm.

    The result from the height determination with network RTK shows big difference in accuracy for the different points. The conclusion is that network RTK measurement would not be a sufficiently accurate height determination method for preparation of a new construction map in an area similar to the one used for this test. Conversely, a construction map drawn up in an open area free from interference obstacles the results show that the network RTK is an approved method for determining height, depending on the requirements of the municipality.

  • 172.
    Andersson, Patrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Utveckling av slipverktyg för handdriven kedjesåg: Ett produktutvecklingsprojekt utfört på Karlstads universitet2018Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This Bachelor’s Thesis documents the process and result of an examining product development project for the Innovation and design programme at Karlstad’s University.

    A concept for a maintenance tool designed for a manual chainsaw has been developed. By applying the phases applied for the product design process described by Johannsson (2013), and by utilizing the knowledge from a comprehensive pre-study, a first concept was established. With a reiterative design process this concept has been developed and made into a first prototype that have been tested, evaluated and adjusted accordingly.

    The construction as described in chapter 2.6- Detail construction is a handheld tool with file gauges specially designed for the manual chainsaw. By using a groove for the chain at the top of the tool, it can be fixed and sharpened without any additional equipment.  A prototype was made by virtual prototyping and constructed by 3D-printing.

    Project should proceed by implementing the changes in the prototype that was observed during testing and then evaluate that result before a manufacturing adoption.

  • 173.
    Andersson, Rasmus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    CAE Tool for Evaluation of Park Lock Mechanism in a DCT Transmission2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A park lock mechanism is a device that is fitted to an automatic transmission on a vehicle. The mechanism lock up the transmission so that no rolling of the vehicle can be done when the vehicle is put in the park position.

    The aim of this thesis is to develop a method in order the evaluate designs on a Park Lock Mechanism (PLM) that can be found in a dual clutch transmission (DCT).

    A Computer Aided Engineering (CAE) tool to calculate the output that is required for an evaluation of a park lock mechanism design will be created. The CAE tool shall calculate static, dynamic, and snap torque on a ratchet wheel in a gradient, with or without a trailer, also the minimum and maximum coefficient of friction between the pawl and cone, pull out force, the maximum amount of rollback, torque needed from the return spring, preload force from actuator spring, and engagement speed.

    The CAE tool created uses an Excel Visual Basics for Applications (VBA) workbook for all calculations. The tool allows the user to choose different vehicles with the required specification to evaluate the values for that PLM.

    The CAE tool will save time and cost if lots of different PLM’s are going to be designed. The CAE tool has potential for future work when more calculations can be added that can be in use for the evaluation the PLM.

    The CAE tool developed by the master thesis student calculates all the required values for evaluation of a PLM design, executed in a fast, efficient, and easy to use program. 

  • 174.
    Andersson, Rikard
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Berglund, André
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Förbättra lågenergihusens materialval ur ett hållbart perspektiv: En studie hur man kan förbättra valet av isoleringsmaterial till vägg och tak samt material till grundkonstruktionen2018Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
  • 175.
    Andersson, Ronja
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Energimärkning torktumlare: Utredning av energimärkningen på torktumlare samt möjliga förbättringsåtgärder vid körningar med liten last2016Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Different parts of the world use energy in different ways and for different purposes. In Sweden the subsector Laundry and Drying represented 6% of the country’s total electricity use in 2007. In the early 80s it was the big household appliances the dominated the increase of energy use in buildings whereas in recent years have been smaller home electronics and small kitchen appliances that have taken the lead. Due to that the need of energy is constantly increasing a more efficient energy use needs to occur. One step in the right direction was made when the publication of the Brundtland Commission and the term ”Sustainable Development” was born.

     

    In Europe the European Union has a goal that in 2020 the energy use shall be reduced by 20% compared to the forecasted use. To reach the goal they have among other things created the eco-design and the energy labelling directives. These directives are designed to improve the products environmental impact during their whole lifecycle and make it easier for the consumers to compare products from an energy perspective with the help of an energy label. For tumble dryers this energy label has been redesigned to more accurately reflect how much energy that is used when the appliances are running.

     

    In this thesis a comparison of the old and the new energy labelling has been made. Beyond this a consumer survey of how the tumble dryers actually are used in the Swedish households has been performed. Based on this, three suggestions of improvement measures when drying small loads have been investigated regarding to energy use, expenditure of time and final moisture content. A tumble dryer has been used to make the comparison between the two labels. Test runs with full and half loads has been run and the results have been used to calculate the energy efficiency classes for both labels. The three improvement measures were run at half load according to the new label, but with changes to external flow adjustment, internal flow adjustment and tennis ball in the drum separately.

     

    The old energy labelling resulted in energy efficiency class D, right on the border to C, and the new labelling in class C. Although the results seem to be equivalent they differ due to the different scales of the labels. According to the old label the dryer resulted at level 4 but according to the new it resulted at level 6 and is therefore less energy efficient when the runs with half load is taken into account.

     

    The consumer survey showed that the load sizes vary a lot from person to person but with an average load of 4,75 kg dry laundry.

     

    The investigation of the suggestions of improved measures showed a very small difference of the energy use, the expenditure of time was better but the textiles got a higher final moisture content compared to the results from the normal method of drying. These three suggestions of improvement are therefore considered to need further investigation or to be replaced.

  • 176.
    Andersson, Simon
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    Pellet production of Sicklebush, Pigeon Pea, and Pine in Zambia: Pilot Study and Full Scale Tests to Evaluate Pellet Quality and Press Configurations2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    More deaths are caused every year by indoor air pollution than malaria, HIV/AIDS and tuberculosis combined. Cooking with traditional fuels such as charcoal and fuelwood with poor ventilation causes the single most important environmental health risk factor worldwide. It also contributes to environmental issues such as deforestation as traditional biomass fuels and cooking stoves are inefficient and requires large quantities of wood. This is especially critical in Africa where the largest regional population growth in the world is expected to occur.

    A solution to these issues was realized through fuel pellets and modern cooking stoves by Emerging Cooking Solutions, a company started by two Swedes and based in Zambia. The production of fuel pellets in Zambia is dependent on pine sawdust from small sawmills and is a declining source of raw material. However, other sources of biomass are available in Zambia such as pigeon pea stalk, an agricultural waste product, and sicklebush, an invasive tree species. If these species are viable for pelletization, the production of pellets can increase while reducing issues with sicklebush and promoting cultivation of pigeon pea. The aim of this work is to evaluate if pigeon pea stalk and sicklebush are viable to pelletize in Zambia and how the press is affected by the different raw materials.

    A pilot study is done at Karlstad University with a single unit press, hardness tester and soxhlet extractor to evaluate how the material constituents correlate to friction in the press channel and hardness of the pellets. The results of the pilot study provide support for full scale tests done in a pellet plant in Zambia. The normal production of pellets from pine sawdust is used as quality and production reference for the tests with pigeon pea stalk, sicklebush, and different mixes of the raw materials. The properties used to evaluate the quality of the pellets are hardness, durability, moisture content, bulk density, and fines. The press configuration is evaluated by logging the electricity consumption by the press motor, calculating the power and specific energy consumption from the logs, and observations during the tests.

    The results show that sicklebush, and mixes of sicklebush with pigeon pea stalk can produce pellets with better quality than the reference pine pellets. An interesting composition is a mix of 80% pigeon pea and 20% sicklebush that produces pellets with the best quality of all the tests. However, pellets produced from sicklebush and pigeon pea show a larger variation in hardness as compared to the reference pellets from pine sawdust. Mixing pigeon pea with pine reduces these variations but reduces the hardness of the pellets below the reference. The press struggles to process sicklebush and pigeon pea stalk with fluctuating power consumption that causes the motor to trip. The inhomogeneity of the materials in sicklebush and pigeon pea are identified to cause the issues in the press. Production improvements are discussed to facilitate the production of pigeon pea stalk and sicklebush pellets.

  • 177.
    Andersson, Sofia
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Study of Dross in Ductile Cast Iron Main Shafts2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The study of dross in ductile cast iron main shafts was performed at Global Castings Guldsmedshyttan AB and presented in this master thesis. The purpose of the study was to obtain answers to why dross defects were present in some of the foundry's casted main shafts, with the main problem located at the flange of the shaft. The chemical composition of the dross formations and which steps in the casting process that increased the dross formation were of interest. The study only included dross in main shafts manufactured at Global Castings Guldsmedshyttan AB.

    Dross particles form when elements such as Mg, Ca, Si and Mn react with O. These elements, which are highly reactive to O, are used in ductile cast irons to achieve the spheroidal graphite nodules that regulate the cast materials ductile properties. If a higher amount of dross particles has formed, the particles will start to cluster, resulting in a growing dross formation. Dross formations works as surface crack initiation points and reduces the castings fatigue strength and ductility.

    During the study it was seen that the cause of dross formations is a combination of many parameters increasing the melts exposure to O resulting in dross defects. The dross formations could be connected to worn out ladles, low melt temperatures, incorrect additions of Mg treatment, lack of an extra slag removal station and finally turbulence as the melt were poured into the mould.

    At Global Castings Guldsmedshyttan AB a greater part of the main shafts containing dross defects were a result of worn out ladles and low melt temperatures. The types of dross found in the main shaft material were mainly Mg, Ca, Si and Al which had reacted with O. S bonded with Mg and Ca was also detected in the dross formations. It was shown that the dross particles could be derived from charge material, Mg treatment and inoculation.

    To avoid dross defects the first step would be to set up an extra slag station, shorten the interval of maintenance of the ladles and to better adjust the melt temperature to the condition of the specific ladle. To minimize dross due to excess Mg a better controlled process would be recommended with an increased number of monitored manufacturing parameters.    

  • 178.
    Andersson, Staffan
    et al.
    Karlstad University, Faculty of Technology and Science.
    Jansson, Mikael
    Karlstad University, Faculty of Technology and Science.
    Framstam till timmerlastbil2008Independent thesis Basic level (professional degree), 15 points / 22,5 hpStudent thesis
    Abstract [en]

    The work is done for the company Höglunds flak in Säffle and aims to develop a new front wall to a timber truck.

    A front wall is what protects the cabin from the logs in case of a collision. The front wall is also used while loading the truck as a loading fixture to beat the logs against.

    The requirements for the front wall from the company are:

    • Easier construction

    • The same deformation at impact testing, surface testing and bending load as the original.

    • Cheaper or the same price as the previous model

    • Withstand the standardization SS 2563, SS 2564

    • Be attractive to the customer

    • Customizable height

    • If possible, get as much production as possible to the own workshop

    The work was divided into two parts where one is to make the plate and how to make it rigid. The second is the beams which are going to keep up the plate and takes the greater part of the impact force.

    Two concepts on the front wall plate, both is of the same material 6082-T6.

    Bending concept.

    The concept consists of an aluminium plate which is bended to an L-profile around the edges to rigid up the plate.

    Square concept.

    This concept consists of a square tube in aluminium which is riveted firmly against the plate.

    Three concepts on the beams. All three are estimated to be in the same material Domex 650

    JL-profile

    Is a profile that is easy to manufacture by bending and is easy to mount on both the plate and in the frame beams.

    I-profile

    The I-beam is made with a larger flange to the plate in order to facilitate the attachment and a small flange on the other side to reduce weight. However, because this is not an original beam it will be manufactured through extrusion.

    W-profile

    W-profile is going to be extruded and is also easy to attach to the plate. It has been developed with the idea of a T-beam which then is stated up with two webs.

    Of the two plate concepts it was the Square concept which was best suited one. The bending concept was not chosen because the material of the plate was for brittle and couldn’t be bent as much as wanted.

    The analysis of the plate was made according to the standard SS2563, SS 2564 with a pressure of a certain distance from the base.

    The FEM analysis at the plate shows that there is no residual deformation, which is the same as the original plate. The square pipe has a lower weight with 19 kg which is 55% lighter compared with the circular pipe profile.

    The profile is able to take up 0,6 kJ more than the Z-profile and 23kg and 23% lighter

  • 179.
    Andersson, Stefan
    Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Analysis of welding in comparable steel grades: Influence of steel grade on the welding process2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis is written to examine the influence of different low carbon steel sheet materials on the GMAW welding process. During welding the properties of the base material influence the productivity of the welding process. The purpose of this thesis is to examine how the choice of material and welding speed affect the welding process and the productivity.

    A literature survey was performed to describe the welding technique and the differences in manufacturing for the sheet materials as well as the effect of alloying and welding on the sheet material. Defects in the weld and methods used to determine them are explained. Test pieces of the different sheet materials were welded with the GMAW process and examined.

    The result shows that there is a variation in the welding process regarding weld penetration. Measurements also show that welding speed and gap have little influence on the hardness of the weld and heat-affected zone and that the S355MC is more likely to suffer from a narrower toe transition radius than S355NL and S355MC Si. This and the higher area in the Y2 region for the S355MC could indicate a stronger inward flow in the weld pool during welding possibly a result of surface active agents such as oxygen and sulphur.

  • 180.
    Andersson, Stefan
    et al.
    Karlstad University, Faculty of Technology and Science.
    Johansson, Andreas
    Karlstad University, Faculty of Technology and Science.
    Tillämpning av effektstabilisering i PLC2008Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the degree project is to make a digital realization of a stabilizer for oscillations in the active power from a hydropower synchronous generator, connected to a power network.

    The implementation is supposed to be done in a PLC which already handles part of the excitation system.

    The power stabilization is achieved by sending a counteracting reference signal to the excitation system which controls the generator’s output power. This counteracting signal can be achieved in several ways.

    Two existing models, standardized by IEEE, for power system stabilizing will be examined, PSS1A and PSS2B.

    A Simulink-model of a distribution net with a generator is constructed to test the stabilizers.

    To perform a digital implementation a discrete transformation of one continuous model is done. This discrete model is also tested to verify the function in comparison to the continuous one.

    The discrete model is reorganized in a form possible to implement in the PLC.

    Comparison between the simulated and the implemented model is made by measurement.

  • 181.
    Andersson, Tim
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Computer Modeling of Thermodynamic Flows in Reactors for Activated Carbon Production2014Independent thesis Advanced level (degree of Master (Two Years)), 300 HE creditsStudent thesis
    Abstract [en]

    There's a big demand for activated carbon in Ghana, it's used for the country's mining industry as well as in a multitude of other applications. Currently all activated carbon is imported despite the fact that the country has a large supply of agricultural waste that could be used for its production. This study focuses on activated carbon production from oil palm kernel shells from the nations palm oil industry.

    Earlier research points to a set of specific conditions needed for the production. The pyrolysis process produces biochar from the biomass and the process is set to take place for 2 h at 600  °C after a initial heating of 10 °C/min. The activation process then produces the activated carbon from the biochar and is set to take place for 2 h at 850 °C with a heating rate of 11.6 °C/min.

    Two reactors are designed to meet the desired conditions. The reactors are both set up to use secondary gases from diesel burners to heat the biomass. The heating is accomplished by leading the hot gases in an enclosure around a rotating steel drum that holds the biomass. To improve the ability to control the temperature profile in the biomass two outlet pipes are set up on top of the reactor, one above the biomass inlet and one above the biomass outlet. By controlling how much gas that flows to each outlet both the heating rate and the stability of the temperature profile can be controlled. The secondary gas inlet is set up facing downwards at the transition between the heating zone (area of initial heating) and the maintaining zone (area of constant temperature).

    The two reactors are modeled the physics simulation software COMSOL Multiphysics. Reference operating parameters are established and these parameters, as well as parts of the design, are then changed to evaluate how the temperature profile in the biomass and biochar can be controlled. A goal area was set up for the profile in the biomass where it was required to maintain a temperature of between 571.5 and 628.5 °C after the initial heating to be seen as acceptable. Similarly a goal area was set for the biochar between 809 °C and 891 °C after the initial heating.

    It's found from the simulations that the initial design of the reactors work well and can be used to produce the desired temperature profiles in the biomass and biochar. Furthermore it's concluded that the initial design for the pyrolysis reactor can be improved by having the gas outlet pipe situated by the biomass inlet face downwards instead of upwards. The redesign improves the overall efficiency of the reactor by increasing the heating rate and maintained temperature.

    The evaluation of the operating parameters led to the conclusion that the secondary gas inlet temperature effects the temperature profile to a greater extent than the gas mass flow in both reactors thereby making them more energy efficient. The increase in efficiency comes with a drawback of more unstable temperature profile. If the temperature profile becomes too unstable it will include temperatures that are too high or too low to be seen as acceptable.

  • 182.
    Andersson, Victor
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Flödesanalys av roterande ventil i ångmotor2018Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This report is a bachelor thesis at Karlstad University in collaboration with Invencon AB and Ranotor AB. The goal was to analyze a rotating valve leading water vapor through an inlet and five outlets. The quantifiable results that were addressed in this project are the mass flow through the outlets and the forces affecting the valve and its shaft (primarily radial forces). The tools used for this project are PTC Creo and ANSA for modelling and mesh as well as ANSYS-CFX and Matlab for computational help. The results show that the specified rotational speed of 4600 rpm doesn’t work for this model. The rotational speed was chosen because of an interest in this specific operating condition. A 3 mm radial gap between the rotating valve and the valve housing proved to cause a leakage in the form of pressure loss inside the valve. The boundary conditions that were laid out for this project are not valid for this operating condition. Since the difference in pressure is large (100 down to 1 bar) the flow is choked. A large difference in pressure also makes it important to adjust the total area of the outlets, since the pressure drop affects the density of the vapor. The forces on the rotating valve that were calculated (using ANSYS-CFX) create a foundation for choosing bearings for the valve. If the construction is modified, and/or the rotating valve will operate at a different rotational speed these forces will be subject to change.

  • 183.
    Andersson, Viktor
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Orsaker till självuppvärmning av furuspån och hur furuspånet förändras under lagring2019Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    To reduce the use of fossil fuels, it is important to increase the use of renewable alternatives such as fuel pellets. Fuel pellets in Sweden are primary produced from various residual products from spruce and pine. Before the production of fuel pellets, the pine sawdust needs some storage time to achieve the right pelletizing properties. During the storing process self-ignition may occur, which is a known and common problem. The purpose of this work was to increase the knowledge about how pine shavings change during laboratory storage, and to demonstrate whether it is the sapwood or heartwood that causes self-ignition. Further, it investigates the differences between pine sapwood and heartwood when it is run through a mechanical dewatering process. This in order to increase the knowledge to industries that handle and stores pine-sawdust, about how and why the problem of self-heating occurs and in the long run can be counteracted. The aim was to prove, by temperature measurements, if the cause of self-ignition is greater in the sapwood or heartwood of the pine. The study will also show how the pine shavings changes during storage through color-, moisture- and NIR-analyses. A checkpoint in the study is to show if the organic compounds, the moisture content and the compression energy are different in the sapwood and heartwood, due to a dewatering process. 

    It was not possible to show if it is a certain part in the pinewood that causes self-ignition through temperature measurements, but during the storage process both color- and moisture differences occurred. The NIR-analyses showed that during both anaerobic and aerobic storage the content of extractives and other compounds in the pine shavings was reduced. The dewatering process did not show big differences between the organic compounds in the sapwood and heartwood. But the process where able to decrease the moisture levels in the shavings even if the heartwood needed more compression energy. 

    To sum up, the study showed that it occurs changes in pine shavings during a storage process even though there was not possible to prove if it is the sapwood or heartwood that causes self-ignition.

  • 184.
    Andersson, Viktor
    Karlstad University, Faculty of Technology and Science.
    Specialemballage för mellanvägg: Ett ergonomiskt emballage2012Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete på 22.5 högskolepoäng har utförts av student Viktor Andersson vid Karlstads universitet under vårterminen 2012. Examensarbetet ingår kursen Examensarbete för högskoleingenjörsexamen i innovationsteknik och design (MSGC12 -vt 2012) och hör till programstrukturen för innovations och designingenjörsprogrammet.

    Volvo Construction Equipment har haft problem med emballaget för artikeln mellanvägg, där av det givna uppdraget.

    Problemen med emballaget är att det har förekommit lackskador på artikeln samt att det är oergonomisk hantering av emballaget. En ny mellanvägg skall snart introduceras och det medför att emballaget idag blir ännu mer oergonomiskt.

    För att undersöka vilka problem som emballaget har en stor research gjorts, som innefattar intervjuer, observationer och litteraturstudier. Underleverantörer och mekaniska verkstäder har kontaktas för att ge sina synpunkter på lösningar och ge ungefärliga prisuppgifter på ett eventuellt nytt kommande specialemballage.

    Efter en grundlig research följdes idégenerering. För att på så sätt få fram en rad kreativa idéer. Idégenerering ledde fram till sex stycken koncept. Utvärdering av koncepten gjordes i två delar, först med matriser och sedan genom diskussioner med flera kunniga personer inom olika områden. Där efter kunde ett konceptval göras. Konceptet som valdes vidareutvecklades med skissmodeller och ritades sedan upp i CAD för att visualisera konceptet i olika lägen.

    Resultatet av detta projekt blev ett ergonomiskt emballage som gör att användaren inte utsätts för någon tung belastning vid användandet av emballaget. Resultatet redovisades med hjälp av en 3D-modell av förslaget, tillverkningsritningar, materialval samt en rapport.

  • 185.
    Andmarsjö, Markus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Simulering av exteriört bussljud: Undersökande av en Ray Tracing metod för ljudsimuleringar2014Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    A method to simulate exterior bus sound with the help of ray tracing has been tested and evaluated. To do this a model of a bus has been built up using CAD software. Dominant noise sources in the bus and material coefficients for the materials included in the bus have been researched. The bus has been imported into the simulation program Odeon where a number of simulations have been performed. Different pass-by simulations have been performed and compared with physical measurements. Different degrees of encapsulation of the engine compartment have been simulated. A grid response has been formulated to optimize the positioning of the absorbers. A calculation error has been found in release 10.13 of the Odeon Software which led to a comparison between Odeon 10.13 and a demonstration version of Odeon 12.

    The results show that the simulation method in its current state performs best when no sound transmission is taken into account. This requires that there are openings in the bus as problems will arise if the bus is simulated with too high a level of encapsulation. Theoretically, no rays would in this case be able to reach any receiver outside the engine compartment. The reason that the transmission loss cannot be taken into account depends on the errors found in Odeon 10.13. The software incorrectly overestimates the sound transmission and transmits rays even in cases where an area is defined to not transmit any rays at all, something that Odeon 12 calculates correctly. Until this is resolved, the simulation method can be used to estimate the energy distribution between the octave bands, the optimal placement of absorbers and to some extent the overall sound level of the bus.

  • 186.
    Andreas, Svensson
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Nabrink, Robin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    GNSS-Styrning: Information för platschefer2013Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
  • 187.
    Andreasson, Frida
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Working Life Science.
    Johansson, Martin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Working Life Science.
    Trivsel på arbetsplatsen: En kvalitativ studie om lärares trivsel på arbetsplatsen2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 188.
    Andrée, Fredrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Nya metoder för vibrationsmätning på vindkraftverk2015Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This project has revolved around finding better ways of overseeing vibrations of the gearbox at a wind power station. The gearbox has been a huge problem at the stations located at Gässlingen and the sooner the warning of an incoming breakdown is at hand the more money you can save from preparations. The work has been carried out together with Askalon AB in cooperation with consults from ÅF. Askalon is a company with a department focused on overseeing vibrations and it is in collaboration with that department the work has been carried out.

     

    During this work, new positions for the sensors and new methods of gathering and analyzing data have been worked out. This was then implemented at a wind power station to be tried out on site. The measurement has been overseen online via remote control and the results have been analyzed in a program called AMS Suite: Machinery Health Manager.

     

    The new type of measurement shows that some kind of damage has been done to a specific part of the gearbox and that there is a risk it might escalate. However the measurement used today has not yet alarmed and therefor the conclusion made from this is that the project has been successful. Therefor it is time to refresh the overseeing of vibrations.

  • 189.
    Andrén, Johanna
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Päbel, Elin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Materialval i byggprocessen: Utvärdering av ”metod för val av sunda ytmaterial”2014Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    All construction has an impact on the environment in some way but with a good method which is also easy to use, the construction industry´s environmental impact could be reduced. When comparing different materials there are many factors to consider if a good health and environmental choice are to be made. In the year 2012 two construction engineering students at Karlstads University developed a method to compare different surface materials from an environmental, health and function perspective for public areas. This report is an evaluation of the method by relating to a real project. The method consists of a multi-criteria analysis which relates to environmental, health and function aspects. In the multi-criteria analysis (the MCA) the various criteria are evaluated and scored for each material and then sums up so that the materials can be compared. When the MCA is completed the economic aspect are then considered. Using a formula where different ratios are calculated and compared.

    In this report the method is tested on a real renovation project and together with people working in the construction industry the report will show if the method is useful and comprehensive enough to produce an environmentally sustainable result. The project that the method has been applied to is a reconstruction of Hagfors old station house to an office building. Twelve different flooring materials for office, hall and common room were developed and calculated using the method. The usefulness of the method was discussed in a workshop with participants from the architect office which was involved in the renovation project.

    The method for selecting good surface materials proved difficult to put into the implementation of the method. It also took time to complete because of all the data that had to be prepared for each material option. The economic aspect of the method was difficult to implement in a realistic way when prices for flooring usually are obtained by quotation regarding the purchase price and installation cost. If the method is to be attractive to the construction industry it must be simple to use and not time consuming because the cost can be difficult to justify to the client. According to the workshop participants the criteria needs to be revised, partly because the thought that some criteria were missing for the method to be more environmental friendly and partly because it would not be possible to compare the performance standards in this way in reality.

    In the construction industry, there is an interest in a working method where similar materials can be compared in an environmental and health point of view. The method presented in this report in neither developed nor easy enough to use in real projects.

  • 190.
    Andrén, Sebastian
    et al.
    Karlstad University.
    Hedin, Mattias
    Business model innovation for asphalt with rubber content: The road towards a circular economy and a sustainable society2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sustainability is a keyword in society today and industries have to contribute to reduce emissions and the use of virgin resources. Every year 90 000 ton old tires are gathered in Sweden. Today mostly used for energy recovery. End-of-life tires has been used in asphalt in the US for almost 50 years and is an effective way to utilize them. There are several possible advantages for rubberized asphalt: noise reduction, higher rutting resistance, increased durability, thinner layers etc. In Sweden, the rubberized asphalt has been tested in 25 different roads, where the Swedish Transport Administration have led the development. Commercially, the product have not yet been successful. There are several different studies for the product in Sweden, but nothing on the business side. The aim in this thesis was to develop a business model for the product on the Swedish market by finding key actors in the value chain, advantages and risks for the rubberized asphalt and studying different market segments. The study has two different research questions, Is there a need for a business model innovation for rubberized asphalt? and How can a business model be created for rubberized asphalt on the Swedish market and what will be the most important factors for establishing the business model? To answer the research questions, qualitative interviews were conducted with 15 different actors in the value chain. The result of the study presents; the value chain for the rubberized asphalt in Sweden, external forces in the industry, a business model and a proposed procurement model. The first question was evaluated and the answer was that business model innovation was needed for rubberized asphalt on the Swedish market, as well as product development and technical statements. The most important factors to penetrate the Swedish market were: spread the information of rubberized asphalt, find segments for market entry, process rubber granulate, handle the product correctly, push for changes in the procurement model and for actors in the value chain to work together. The results can serve as a tool for business model innovation and may be used for other sustainable and recycled products. The report also presents several practical contributions that can be of interest for the asphalt industry.

  • 191.
    Andrésen, Albin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Att förutsäga temperatur, utgående fukthalt och tryckfall i en pneumatisk transporttork2014Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Användningen av pellets har ökat kraftigt de senaste åren och har blivit ett viktigt verktyg för att minska miljöpåverkan. I energibranschen är viktigt utreda möjligheten att effektivisera tillverkningsprocessen för att ligga i framkant av utvecklingen och göra bränslet till ett attraktivt val för konsumenterna. En stor del av pelletstillverkarnas utgifter går till att torka det råmaterial som pellets består av. Torkning och transport av material är två energikrävande processer som är nödvändiga i många industrier och kan ibland innebära stora utgifter såväl kostnadsmässigt som miljömässigt. Pneumatisk transporttorkning är ett sätt att kombinera torkning och transport av material och tekniken kan vara lämplig att använda vid pelletstillverkning. På Karlstads Universitet finns en pneumatisk transporttork vars syfte är att forska och utveckla torkning av råmaterial.I den här studien byggdes en modell för att hjälpa användaren att förutse vilket tryckfall och utgående fukthalt som kan förväntas vid torkning av sågspån. Modellen kan användas som ett hjälpmedel vid planering av försök i Karlstads Universitets pneumatiska transporttork.Modellen byggdes i beräkningsverktyget Excel. Dess resultat jämfördes med testserier genomförda i Karlstads Universitets pneumatiska transporttork. Totalt genomfördes trettiotre olika testserier då tryckfall och utgående fukthalt jämfördes. Testserierna skiljde sig ifrån varandra i fråga om massflödet luft, material och ingående lufttemperatur.Vid lägre lufttemperaturer förutsåg modellen en högre utgående fukthalt än vad som kunde uppmätas. När den ingående lufttemperaturen var 120 °C förutsågs ibland rätt, ibland högre och ibland lägre fukthalt i jämförelse med testserierna. Tryckfallet kunde med god noggrannhet förutsägas då lufthastigheten var låg. Då hastigheten var högre var differensen mellan mätdata och modellen större.Känslighetsanalysen visade att en möjlig förklaring till att modellen i vissa fall förutsåg en hög fukthalt kan vara att vissa materialegenskaper var felaktigt antagna. Störst påverkan hade antagandena angående partiklarnas densitet och antalet partiklar som flödar genom systemet per sekund. Det simulerade tryckfallet påverkades inte av ovan nämnda antaganden.Modellen har stor utvecklingspotential men vidare studier rekommenderas för att skapa en bättre förståelse för såväl den pneumatiska transporttorken som modellen. Studierna bör främst riktas mot att bestämma partikelegenskaper och att kontrollera hur väl tryckfallet överensstämmer men mätdata i hela torken. Om det genomförs finns goda möjligheter att modellen kan bli användbar för användare av Karlstads Universitets pneumatiska tork.

  • 192.
    Andrésen, Alma
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Automatiserad matning av stänger till gängmaskin2015Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Målet med examensarbetet var att ta fram ett koncept för automatiserad i- och urmatning av stänger till en gängmaskin. Målet var också att 3D-modellera och göra 2D-ritningar på samtliga ingående mekaniska delar samt att genomföra en styrteknisk studie.

    Arbetet har utförts på uppdrag av Lars Eriksson och Annika Persson på Ground Machinery Applications AB i Sunne. De krav som ställdes på konstruktionen var enkelhet att montera och demontera, att man enkelt ska kunna byta ut komponenter som utsätts för slitage. Det skall finnas möjlighet att montera skyddskåpor där klämrisk kan uppstå. Krav på att stången skall hållas på plats av ett mothåll under gängningen samt att konstruktionen skall utföra så få och enkla rörelser som möjligt. Även vilka dimensioner av stänger konstruktionen skall klara definierades.

    Resultatet av arbetet blev en konstruktion bestående av tre pelare försedda med vinkelstål vilka stången inledningsvis vilar i. Stången matas i axiell led in mot gängmaskinen genom att skjuvas med hjälp av magnetkraft. Magneten är fästad på en axel vinkelrät till stången och den förflyttas i längdled och för på så vis med sig den magnetiska stången. Under gängningen fälls ett mothåll över stången för att se till att denna inte skenar iväg, vilket händer vid gängning av en skev stång. Då gängningen är färdig matas stången tillbaka till ursprungsläge av samma magnetkraft för att slutligen tippas av genom att vinkelstålen fälls kring en gångjärnspunkt.

    Samtliga av konstruktionens rörelser utförs med hjälp av pneumatiska cylindrar som arbetselement. Genom beräkningar har respektive cylinders krävda area tagits fram för att säkerställa att dessa klarar belastningen. Dessa belastningar visade sig vara ytterst små och därför har val av arbetselement istället begränsats av slaglängden. Med hjälp av ett följddiagram som beskriver i vilken ordningsföljd dessa element arbetar samt med en utarbetad styrlogik som anger med vilka villkor rörelserna utförs, har ett övergripande, pneumatiskt schema upprättats. Schemat består, utöver arbetselementen av ett styrelement för respektive cylinder. Dessa är pneumatiskt styrda, bistabila, 5/2-riktningsventiler som styr cylindrarna till främre eller bakre läget. Varje riktningsventil har två lägen och styrs i sin tur av signalventiler som är elektiskt styrda, bistabila, 3/2-ventiler. Dessa signalventiler tar emot elektriska signaler från induktiva sensorer som finns på nio olika positioner i konstruktionen.

  • 193.
    Angulo, Julio
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT. Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013).
    Designing for Usable Privacy and Transparency in Digital Transactions2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    People engage with multiple online services and carry out a range of different digital transactions with these services. Registering an account, sharing content in social networks, or requesting products or services online are a few examples of such digital transactions. With every transaction, people take decisions and make disclosures of personal data. Despite the possible benefits of collecting data about a person or a group of people, massive collection and aggregation of personal data carries a series of privacy and security implications which can ultimately result in a threat to people's dignity, their finances, and many other aspects of their lives. For this reason, privacy and transparency enhancing technologies are being developed to help people protect their privacy and personal data online. However, some of these technologies are usually hard to understand, difficult to use, and get in the way of people's momentary goals.

    The objective of this thesis is to explore, and iteratively improve, the usability and user experience provided by novel privacy and transparency technologies. To this end, it compiles a series of case studies that address identified issues of usable privacy and transparency at four stages of a digital transaction, namely the information, agreement, fulfilment and after-sales stages. These studies contribute with a better understanding of the human-factors and design requirements that are necessary for creating user-friendly tools that can help people to protect their privacy and to control their personal information on the Internet.

  • 194.
    Angulo, Julio
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Information Systems and Project Management. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Usable Transparency through network representations and analyses2015In: The Future of Networked Privacy: Challenges and opportunities, 2015Conference paper (Refereed)
    Abstract [en]

    We explore how concepts from the field of network science can be employed to inform Internet users about the way their personal identifiable information (PII) is being used and shared by online services. We argue that presenting users with graphical interfaces that display information about the network structures that are formed by PII exchanges can have an impact on the decisions users take online, such as the services they choose to interact with and the information they decide release.

  • 195.
    Angulo, Julio
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Information Systems and Project Management.
    Fischer-Hübner, Simone
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Pulls, Tobias
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Ulrich, König
    HCI for Policy Display and Administration2011In: Privacy and Identity Management for Life / [ed] Jan Camenish, Simone Fischer-Hübner and Kai Rannenberg, Berlin: Springer Berlin/Heidelberg, 2011, 1, p. 261-277Chapter in book (Refereed)
    Abstract [en]

    The PrimeLife Policy Language (PPL) has the objective of helping end users make the data handling practices of data controllers more transparent, allowing them to make well-informed decisions about the release of personal data in exchange for services. In this chapter, we present our work on user interfaces for the PPL policy engine, which aims at displaying the core elements of a data controller's privacy policy in an easily understandable way as well as displaying how far it corresponds with the user's privacy preferences. We also show how privacy preference management can be simplified for end users.

  • 196.
    Angulo, Julio
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Fischer-Hübner, Simone
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Wästlund, Erik
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Psychology. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT. Karlstad University, Faculty of Economic Sciences, Communication and IT, Service Research Center.
    Pulls, Tobias
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Towards Usable Privacy Policy Display & Management: The PrimeLife Approach2011In: Proceedings of 5th International Symposium on Human Aspects of Information Security & Assurance / [ed] Steven Furnell, Plymouth: University of Plymouth , 2011, p. 108-118Conference paper (Refereed)
  • 197.
    Angulo, Julio
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Wästlund, Erik
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Social and Psychological Studies.
    Identity Management through “Profiles”: Prototyping an Online Information Segregation Service2013In: Human-Computer Interaction. Users and Contexts of Use: 15th International Conference, HCI International 2013, Las Vegas, NV, USA, July 21-26, 2013, Proceedings, Part III / [ed] Masaaki Kurosu, Springer Berlin/Heidelberg, 2013, Vol. 8006, p. 10-19Conference paper (Refereed)
    Abstract [en]

    Whereas in real everyday life individuals have an intuitive approach at deciding which information to disseminate to others, in the digital world it becomes difficult to keep control over the information that is distributed to different online services. In this paper we present the design of a user interface for a system that can help users decide which pieces of information to distribute to which type of service providers by allowing them to segregate their information attributes into various personalized profiles. Iterative usability evaluations showed that users understand and appreciate the possibility to segregate information, and revealed possible improvements, implications and limitations of such an interface.

  • 198.
    Ankartoft, Robin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Utveckling av kaffemaskin för event2016Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This report covers a product development project conducted by Robin Ankartoft as Bachelor of Science thesis for the innovation & design engineer program at Karlstad University. 

    The assignment was provided by the company 3TEMP AB, Arvika. The company has requested a concept proposal of a coffee machine for events. The coffee machine has to be able to serve coffee fast and during long periods of time, to the visitors of different events. The product also has to be able to be used in different environments, as for example in events like skiing contests, festivals, hockey games or weddings. In the assignment from the company 3TEMP, a powerful, flexible and user-friendly product was sought, that also had good ergonomic qualities. 

    The objective of the project has been to develop a product concept of a coffee machine for events, using the design methodology and an engineering approach. The concept shall meet the needs, requirements and expectations of the user and of the company. It should also have a design that because of its functionality and idiom stands out among today’s products.  

    The outcome of the project was a concept proposal of a coffee machine for events. The concept is based on knowledge of the user to make the product user-friendly by having good ergonomics and being easy to understand as well as use. The concept aligns with the vision of 3TEMP and is, thanks to its design and functionality, considered to stand out among today’s products.

  • 199. Annas, Mattias
    et al.
    Sundberg, Niklas
    Effektivisering av byggproduktion: vid byte av fönster2011Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
  • 200.
    Annebäck, Jenny
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    A Minor Field Study on development of recycling service for used PET bottles at hotels in Uganda2013Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Through interviews, research, observations and the use of service design methods the author of this report, Jenny Annebäck, executed a Minor Field Study within the field of recycling of PET bottles in Uganda. The project work resulted in thorough studies of service design thinking and methodology, sustainable development, the market and situation in Uganda as well as the consumer group concerned about sustainable development. The result was a pre-study of a future development of a recycling service, visualized through two stakeholder maps, personas and a customer journey map. These three tools constitutes a beginning and a solid ground for further work with developing the service. A service that can contribute to a more sustainable development in the country of Uganda. In the report, examples are stated how to continue with the project as well as how it can be applied in other developing countries.

    The project work of this Minor Field Study(MFS) lasted from November 2011 until June 2012, as a degree project of 22,5 ECTS credits for the Degree of Bachelor of Science in Innovation and Design Engineering at Karlstad University. The MFS program is organized by the Swedish International Programme Office for Education and Training and financed by the Swedish International Development Cooperation Agency, enabling graduating students to perform a thesis in a developing country.

    Jenny Annebäck spent the first two months of the project time in Jinja, Uganda, together with her project partner Olga Sabirova Höjerström, both students at Karlstad University. The two project group members performed this Minor Field Study together with Sarah Keller, industrial designer and general manager at Uganda Innovation Factory(UIF). UIF is a product and graphic design company situated in Jinja, working with local designers to encourage Ugandan design and production for the global market. The supervising teacher of this project has been Monica Jakobsson and the examiner professor Fredrik Thuvander, both belonging to the Faculty of Technology and Science at Karlstad University. 

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