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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Designing for a Multiple Screen Setup : Interactive Storytelling and Attention Guiding for a Perceivable and Engaging Experience of UTM Explore

Bertzen, Charlotte, Basjuka, Jekaterina January 2022 (has links)
An interactive multiple screen visualisation might become an opportunity for engaging and illustrative presentations of scientific, complex, and abstract research. With multiple (interactive) monitors, storytelling and interfaces could bring engagement, immersion, and attraction to the audience. The challenge of designing for a multiple screen setup is that the amount of information can be overwhelming, causing the perception of it and engagement with it to decrease. This thesis explores approaches that could enhance the perception and engagement of the content for a multiple screen setup. The Research Through Design approach sets the structure for the entire thesis. It consists of methods for exploration, concepting, prototyping, and user testing. By following this research approach, three versions of a prototype were developed and tested which led to the results of this thesis. The overall nature of this research process was exploratory and the design decisions were applied during the activities. The main findings of this thesis regarding the multiple screen setup during the research process included three attention guiding approaches: black and white, blur, and pause, and according to the user test participants, the preferred approach was black and white. The second vital aspect of the research and testing were the five-act story arc and interactive storytelling structures. According to the data from user tests, interactivity helped to increase the engagement and perception of the exhibition piece.
152

THE BEST WAY TO WORK : Increasing the efficiency through layout changes and standardization

Backéus, Lina January 2021 (has links)
This is a master thesis done in the program of industrial design engineering at Luleå University ofTechnology, conducted during the spring of 2021. The project is a collaboration with Epiroc RockDrills AB which is a leading global company in the mining industries, and the workshop in which thisthesis is made manufactures and assembles rock drills sold worldwide. The aim of this thesis is toincrease the utilization of three lathes in the workshop that are often left unused when theiroperators have to leave the machines to perform other tasks. This is due to short operation timesthat require the operator to be present.The project follows a cyclic method in order to force the work forward without worrying aboutmissing information. There were three cycles with different aim. In the first cycle, the focus was onplanning the project and mapping the current state. In the second, a requirement specification wasmade and concepts were created. These concepts were further developed in the third cycle. Finally arecommendation was made.The current state was mapped using different methods like interviews and spaghetti diagram. Thesemethods showed that the lathes were unused mainly during setups, and that setups were timeconsuming due to equipment being placed far away from the lathes. The result showed that manyproblems could be related to bad layout design and lack of standardized work. In order to create abetter layout for the operators, a relationship chart was made and several suggestions constructedbased on it. The purpose of the layout changes was to get necessary equipment closer to the lathesin order for the setups to be performed faster. All suggestions were compared to the requirementspecification and only three were further developed during the third cycle.The lean tool SMED (Single Minute Exchange of Die) was used to create a standard for setups. Thisstandard was further developed into a work instruction to be better visualized for the operators.The final recommendation is to make layout changes according to one of the layouts presented inthis report, and to implement the work instruction. These changes will increase the utilization bypreparing as much as possible before the lathe is tuned off.
153

Analytické metody v motorsportu / Analytical Methods in Motorsport

Růžička, Bronislav January 2013 (has links)
This dissertation is focused on proposal for simplified data analyze approach for sport-car vehicle dynamic evaluation with relationship to possibility for qualified estimation of set-up parameters influence for overall vehicle performance. In common practice can be usual overlapping effect caused by concurrent changes of car setup elements if performed in the same moment with resulting in not correct or hardly definable process determination for evaluation and decision about next steps in car development. For analyze of these multidimensional data is then chosen process with approach by Linear Regression Model (LRM). In dissertation is proposed basic philosophy with concern on specificity of car vehicle dynamics, performed experiment with defined inputs including analyze and interpretation method of obtained outputs. This methodic take into account also possibility for general application of multidimensional data analyses not only in motorsport, but as well for dynamic behavior diagnostics of technical systems where finding of optimal running condition depends on multi-parametric setup whose combination must reflect often changes of outer conditions too.
154

Facilitating Radical Collaboration in Open Innovation : A case study in collaboration with IKEA / Möjliggöra radikala samarbeten i öppna innovationslandskap : En fallstudie i samarbete med IKEA

Strömstedt, Linnéa, Vaagenes Rehmberg, Erik January 2021 (has links)
The increased customer demand for innovative and sustainable solutions implies that companies need to seek knowledge, and insights, beyond their traditional business models. This by opening up barriers and collaborating with other stakeholders. Using this approach is referred to in the literature as practicing open innovation. There is however a lack of research on open innovation concerning radical innovation and collaboration. The purpose of this report is to fill this research gap by investigating how a large incumbent company can set up radical collaboration in an open innovation space. The gap will be filled by conducting a qualitative and explorative cross-case analysis with the hosting company of this study, IKEA, and the research questions presented in this report aims to assist IKEA in the set of radical collaboration. The research question and related results were divided into four parts; Strategy implications, partner selection criteria, challenges and success factors. Regarding the first sub-research question, the strategy of the OIS should be aligned to the long-term goals of the parent firm but the short-term targets should not be controlled. This in order to give the OIS mandate to come up with unexpected and radical solutions. Moreover, in the partner selection process, important criteria to consider for radical collaboration are shared values, culture, and commitment to the project. Concerning challenges with radical collaboration, these are: Clear expectations, Contracts, Identifying focus areas, Implementation of the innovations, Innovation strategy renewal, Introduction of a new concept, NDA’s, Outsourcing and Organizational behavior. Lastly, the findings show that autonomy, self-control, communication, and structure are important success factors. The related recommendation of this thesis is that large established companies, looking to pursue radical collaboration in an open innovation format, should consider these insights to be successful. It should however be made clear that radical innovation practices tend to be more complex and time-consuming. Thus, KPIs for success may need to be revisited in firms traditionally seeking incremental innovations with in-house innovation practices. / Med en ökande efterfrågan från kunder på innovativa och hållbara lösningar behöver företag söka kunskap och resurser utanför sina traditionella affärsmodeller. Detta genom att öppna upp sina interna processer och samarbeta med andra. Att använda detta tillvägagångssätt hänvisas till i litteraturen som att utöva “öppen innovation”. Det saknas dock forskning i ämnet som rör radikal innovation och samarbete. Syftet med denna rapport är att fylla detta forskningsgap genom att undersöka hur ett stort etablerat företag kan starta upp radikala samarbeten i ett öppet innovationslandskap. Gapet kommer att fyllas genom att utföra en kvalitativ och explorativ flerfallsstudie med ett värdföretag, IKEA, och forskningsfrågorna som presenteras i denna rapport har som mål att skapa ett ramverk för att hjälpa IKEA introducera radikala samarbeten. Forskningsfrågan och relaterade resultat delades in i fyra delar; Strategi implikationer, partnervalskriterier, utmaningar och framgångsfaktorer. När det gäller den första forskarfrågan bör innovationsstrategin anpassas till moderföretagets långsiktiga mål, men de kortsiktiga målen bör inte kontrolleras. Detta för att ge initiativet mandatet att komma med oväntade och radikala lösningar. Dessutom är viktiga kriterier att ta hänsyn till, för radikala samarbeten i urvalsprocessen av partners, att de samarbetande parterna delar värderingar, kultur och engagemang för projektet. Vad gäller utmaningar för radikalt samarbete är dessa de mest kritiska: Tydliga förväntningar, Kontrakt, Identifiera fokusområden, Implementering av innovationer, Förnyelse av Innovationsstrategi, Introduktion av ett nytt koncept, Sekretessavtal, Outsourcing och Organisatoriskt beteende. Slutligen visar resultaten att autonomi, självkontroll, kommunikation och struktur är viktiga framgångsfaktorer. Den avslutande uppmaningen är att stora etablerade företag, som vill sträva efter radikalt samarbete i ett öppet innovationslandskap, bör ha dessa insikter i beaktning för att initiativet ska bli framgångsrikt. Det bör dock klargöras att radikala innovationsmetoder tenderar att vara mer komplexa och tidskrävande. Därför kan KPI:er för framgång behöva ses över hos företag som traditionellt söker inkrementell innovation med interna innovationsmetoder.
155

3D obstacle avoidance for drones using a realistic sensor setup / Hinderundvikande i 3D för drönare med en realistisk sensoruppsättning

Stefansson, Thor January 2018 (has links)
Obstacle avoidance is a well researched area, however most of the works only consider a 2D environment. Drones can move in three dimensions. It is therefore of interest to develop a system that ensures safe flight in these three dimensions. Obstacle avoidance is of highest importance for drones if they are intended to work autonomously and around humans, since drones are often fragile and have fast moving propellers that can hurt humans. This project is based on the obstacle restriction algorithm in 3D, and uses OctoMap to conveniently use the sensor data from multiple sensors simultaneously and to deal with their limited field of view. The results show that the system is able to avoid obstacles in 3D. / Hinderundvikande är ett utforskat område, dock för det mesta har forskningen fokuserat på 2D-miljöer. Eftersom drönare kan röra sig i tre dimensioner är det intressant att utveckla ett system som garanterar säker rörelse i 3D. Hinderundvikande är viktigt för drönare om de ska arbeta autonomt runt människor, eftersom drönare ofta är ömtåliga och har snabba propellrar som kan skada människor. Det här projektet är baserat på Hinderrestriktionsmetoden (ORM), och använder OctoMap för att använda information från många sensorer samtidigt och för att hantera deras begränsade synfält. Resultatet visar att systemet kan undvika hinder i 3D.
156

Development of a microfluidic device to study simultaneous crystallization in the LIBs recycling process / Utveckling av en mikrofluidisk enhet för att studera samtidig kristallisering i LIB:s återvinningsprocess

Solanki, Shefali Paresh January 2023 (has links)
Återvinning av litiumjonbatterier (LIB) är avgörande på grund av kritiska råmaterialreserver och miljöhänsyn vid kassering. Hydrometallurgisk LIB-återvinning, en framstående industriell teknik, står inför kostnadseffektivitets- och komplexitetsutmaningar. Samtidig kristallisering visar lovande för effektivisering av återvinning genom att extrahera föreningar från förbrukad batterilut med flera komponenter, vilket kräver hög renhet och effektiv kristallseparation. Detta innebär emellertid att man förhindrar oönskade polykristallina partiklar och samkristaller.Kristallisering är vanligt vid LIB-återvinning, men vanligtvis från enkomponentlösningar för att undvika föroreningar. Kärnbildningskontroll, särskilt i flerkomponentlösningar, är fortfarande utmanande, vilket påverkar industriell effektivitet. Sådd, en vanlig kontrollmetod, inducerar ofta oavsiktliga polykristallina partiklar och vätskeinneslutningar, som understuderas på grund av experimentella begränsningar. Microfluidics erbjuder ett värdefullt verktyg för att studera kristallisationskinetik, växla från utrustningsbaserad till prediktiv fysikalisk-kemisk design. Förbättrad blandning och värmeväxling gör den idealisk för kärnbildningsforskning under kristallisation. Denna avhandling fokuserar på avgörande aspekter av samtidig kristallisation. Huvudsyftet är att utveckla en optimerad mikrofluidisk design och simulera mikrofluidikkanalen för att bestämma initiala processparametrar för experiment samt att få det mest förutsägbara området för kristallbildning inom mikrofluidik. Utmaningar i de mikrofluidiska kristallisationssystemen, såsom kanalblockering, som lätt kan uppstå på grund av kristallbildning eller agglomerationer, har tyvärr begränsat de experimentella resultaten. Icke desto mindre kommer denna avhandling att stödja ytterligare experiment med mikrofluidikanordningen under mikroskopi som kommer att hjälpa till att övervinna dessa utmaningar. Arbete med att minska begränsningarna i denna avhandling kan hjälpa till att förstå multikomponentkristallisationen i realtid och faktiskt den nödvändiga uppställningen och infrastrukturen för mikrofluidikexperiment och i förlängningen bidra till att minska de hydrometallurgiska stegen i komplex metallåtervinning. Därför bidrar det till att främja områdena batteriåtervinning, mikrofluidik och samtidig kristallisering. / Recycling lithium-ion batteries (LIB) is essential due to critical raw material reserves and environmental concerns during disposal. Hydrometallurgical LIB recycling, a prominent industrial technology, faces cost-efficiency and complexity challenges. Simultaneous crystallization shows promise for streamlining recycling by extracting compounds from multicomponent spent battery liquor, demanding high purity and effective crystal separation. However, this entails preventing unwanted polycrystalline particles and cocrystals. Crystallization is common in LIB recycling, but usually from single-component solutions to avoid impurities. Nucleation control, especially in multicomponent solutions, remains challenging, affecting industrial efficiency. Seeding, a common control method, often induces unintended polycrystalline particles and fluid inclusions, which are understudied due to experimental limitations. Microfluidics offers a valuable tool for studying crystallization kinetics, shifting from equipment-based to predictive physical-chemical design. Enhanced mixing and heat exchange make it ideal for nucleation research during crystallization. This thesis focuses on crucial aspects of simultaneous crystallization. The main objective is to develop an optimized microfluidic design and simulate the microfluidic channel to determine initial process parameters for experimentation as well as to get the most predictable region of crystal formation within microfluidics. Challenges in the microfluidic crystallization systems, such as channel blockage, which can easily occur due to crystal formation or agglomerations, have unfortunately limited the experimental results. Nonetheless, this thesis will support the further experimentation of the microfluidics device under microscopy which will help to overcome these challenges. Work on reducing the limitations of this thesis can assist in understanding the multicomponent crystallization in real-time and indeed, the necessary setup and infrastructure for microfluidics experiments and in the long run help reduce the hydrometallurgical steps in complex metal recycling. Hence, it contributes to advancing the fields of battery recycling, microfluidics, and simultaneous crystallization.
157

Development of MOKE Spectrometer for Magneto-optical Studies of Novel Magnetic Materials and Quantum Structures

Tanaka, Hiroki 29 December 2008 (has links)
No description available.
158

Design and Development of an Experimental Test Rig for Heat Sinks / Utveckling och konstruktion av en experimentell testrigg för värmesänkor

Abraham, Gabriel Kaduvinal January 2020 (has links)
Heat sinks are used mainly to take away the excessive heat which are produced in a component. This transfer of heat enables a smooth operation of the system with the heat generating component. The efficiency of heat sink is often dependent on the amount of heat it can take away within the smallest duration of time. Several designs and manufacturing techniques have been developed to improve this performance of heat sinks. This project aims at building a test rig which can be used to test the efficiency of heat sinks. The test rig should be designed to be modular, i.e. it should be able to test heat sinks of different sizes and also adhering to the design requirements. The project started with a broad information search on heat sinks and different testing methods. A system architecture was formulated for this test rig as a beginning stage and to find the different architectural components. The main principal components were selected fulfilling the design requirements. A chiller with pump, a flow meter with controller, temperature and pressure sensors and piping’s including a flexible pipe were the main components of the system created. When the specific components were chosen, the design was embodied and the components were arranged in a compact manner as a SolidEdge CAD-model. After several design iterations, a final design was selected. The experimental test rig was then built in the flow lab. The built experimental test setup is able to be adjusted to install heat sinks of different sizes making it modular in design. Future work to improve the performance of the test rig is also suggested. / Värmesänkor, som exempelvis kylflänsar, används främst för att transportera bort värme som orsakas av förluster i en komponent. Denna värmeöverföring möjliggör en smidig drift av systemet där den värmegenererande komponenten ingår. Värmesänkans effektivitet beror på hur mycket värmeeffekt den kan transportera bort. Flera olika konstruktioner och tillverkningstekniker har utvecklats för att förbättra värmesänkors kylprestanda. Målet med detta projekt är att bygga en testrigg som kan användas för att testa kylflänsars effektivitet. Testriggen ska utformas så att den är modulär, dvs. den ska kunna användas för att testa kylflänsar av olika storlekar. Projektet startade med en bred informationssökning om kylflänsar och olika testmetoder. En systemarkitektur skapades som ett början och för att hitta systemets olika principkomponenter. De viktigaste huvudkomponenterna som uppfyllde designkraven valdes sedan. En kylare med pump, en flödesmätare med regulator, temperatur- och tryckgivare och rörledningar, inklusive ett flexibelt rör var de viktigaste komponenterna i det system som skapades. De specifika komponenterna valdes sedan och de representerades och arrangerades på ett kompakt sätt som en system-CAD-modell i SolidEdge. Efter flera iterationer valdes en slutlig konstruktion, och den experimentella testriggen byggdes sedan i flödeslaboratoriet. Den experimentella testriggen kan justeras för att installera kylflänsar av olika storlekar, vilket innebär att den, i viss mån, är modulär. Framtida arbeten för att förbättra testriggens prestanda föreslås också.
159

Simulation of a three-wheeled electric vehicle / Simulering av ett trehjuligt elfordon

Kuan, Dick, Zettel, Lucas Svensson January 2024 (has links)
Vehicle simulators are often built from scratch, using well-established software frameworks with custom vehicle models. Since the development of a simulator is a very time consuming process,  the purpose of this thesis paper was to explore a different alternative by evaluating the open-source vehicle system ChaosVehicle (CV) in Unreal Engine 5. The goal was to build a simulator using CV and assess its performance in imitating certain aspects of a three-wheeled electric vehicle, including acceleration, coasting and braking behaviors in a straight line.The simulator was set up according to the data provided by the vehicle manufacturer, OMotion. By comparing the simulations with real world driving data, it was determined that the simulator achieved a relative error below 16% in imitating the coasting behavior of the real vehicle. Further, with regards to the brake performance, the simulator has managed to achieve a relative error of below 15% when not accounting for velocities below 10 km/h. Due to the noise present in the real world driving data, it was inconclusive as to whether the simulator had accurately predicted the acceleration behavior of the  real vehicle. After a preliminary analysis of the plugin, it was discussed whether CV was as extensible as hypothesized. While the framework is open-source, it was difficult to fully grasp the system due to incomplete documentation of the source code and the user interface. Further work in mapping how the physics model in CV is integrated to the game engine would shed some light on this matter.
160

Experimentell-numerische Vorgehensweise zur Entwicklung von Probekörper-Setups für die Charakterisierung technischer Elastomere

Kanzenbach, Lars 12 December 2019 (has links)
Für die Materialcharakterisierung und Parameteridentifikation von technischen Elastomeren werden homogene Probekörper benötigt. Eine besonders wichtige Beanspruchungsart ist dabei der einachsige Zug/Druck. Für Versuche dieser Art findet die Standard-Hantel Anwendung, die für kombinierte Zug-/Druckversuche geeignet ist. Allerdings lässt sich hier schon bei geringen Druckbelastungen ein inhomogener Messbereich detektieren. Ein Ziel dieser Arbeit besteht in der Entwicklung eines neuen und verbesserten Probekörpers, der für hochpräzise Zug-/Druckversuche geeignet ist. Im Gegensatz zur Standard-Hantel wird der für Messungen zugänglich gemachte homogene Messbereich deutlich verbessert. Darüber hinaus soll der Bereich der maximal erreichbaren Stauchung signifikant erhöht werden. Der Probekörper selbst weist dabei eine verhältnismäßig einfache Hantelgeometrie mit verlängertem Mittelteil auf. Durch ein spezielles Design der Halterungsgeometrie kann sowohl ein homogenes Verzerrungsfeld erreicht als auch eine hohe Knickstabilität gewährleistet werden. Die Grundidee besteht dabei darin, dass der Probekörper mit zunehmender Stauchung immer weiter mit der Halterungsgeometrie in Kontakt tritt und dadurch seine knickgefährdete Länge reduziert wird. Mit Hilfe eines speziellen Halterungsalgorithmus kann eine neue, verbesserte Halterungsgeometrie berechnet werden. Mit dem entwickelten Probekörper-Setup (bestehend aus Hantel- und Halterungsgeometrie) lassen sich dann eine Vielzahl phänomenologischer Eigenschaften von technischen Elastomeren wie Payne- Effekt, Mullins-Effekt, Erholungs- und Relaxationsverhalten vorzugsweise bei extremen Stauchungen (bis zu 70 %) untersuchen. Ein weiteres Ziel dieser Arbeit besteht in der Entwicklung eines Scherprobekörpers zur Realisierung präziser Schermessungen. Das Design soll dabei auf einem flächigen Probekörper (Elastomermatte) beruhen, um Alterungsuntersuchungen, Untersuchungen mit faserverstärkten Materialien und Versuche mit Vorreckungen realisieren zu können. Im Gegensatz zu herkömmlichen Scherprobekörpern soll dabei auf eine stoffschlüssige Verbindung mittels Kleben oder Anvulkanisieren aufgrund von Materialirritationen oder Schrumpf verzichtet werden. Im Rahmen dieser Arbeit wurde diesbezüglich ein spezielles Fixierdesign mit Stiften entwickelt, welches zur Ausbildung nahezu homogener Scherdeformationen führt. Damit lassen sich eine Vielzahl wichtiger Eigenschaften bei einer annähernd homogenen Scherdeformation untersuchen. / Homogeneous test specimens are required for material characterization and model parameter identification. An important kind of loading is uniaxial tension/compression. For this, a standard dumbbell is available for combined tension-compression tests. But even for small compressive strains the standard dumbbell leads to an inhomogeneous stress state in the measuring zone. One aim of this work is the development of a new test specimen, which is suitable for high-precision tension/compression tests. In comparison to the standard dumbbell the homogeneity in the measuring zone is significantly improved. Furthermore, the range of maximal compression is increased substantially. The test specimen itself consists of a slender dumbbell structure. By a special design of the mounting geometry, homogeneous stress and strain fields as well as a high stability can be achieved. For an increasing compression, the test specimen comes into contact with the mounting geometry and the critical length is reduced. By means of dynamic analysis, the mounting geometry was calculated and optimized. This method is a powerful tool for developing new mounting geometries, by taking into account both the stability and the homogeneity characteristic. With the developed specimen-setup (consisting of dumbbell and mounting geometry), the phenomenological characteristics of rubber like Payne effect, Mullins effect, recovery and relaxation behavior can be investigated up to a compressive strain of 70 %. Another aim of this work is the development of a shear specimen, which enables precision shear measurements for large shear values. The design is based on a planar test specimen (rubber mat) in order to enable ageing tests, tests with fibre-reinforced materials and tests with pre-stretching. In contrast to other shear specimens, a material-locking connection by gluing or vulcanizing sould be avoided in consequence of material irritation or shrinkage. For this, a special fixing design was developed, which enables a uniform initiation of shear deformation for different rubber thicknesses. Finally, the new shear specimen enables the investigation of typical rubber properties.

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