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Senast publicerade

Din boendemiljö - dröm eller verklighet
(1978) Enkel, Newton
Uppsatsen analyserar relationen mellan arkitektur, samhällsstruktur och människors välbefinnande, med särskilt fokus på hur planering och bostadsutformning påverkar sociala relationer och livskvalitet. Den lyfter behovet av mer människocentrerade och hållbara miljöer som främjar gemenskap och funktionalitet.
En verklig reform, en markbostad för alla
(1975) Enkel, Newton
Uppsatsen behandlar samhällsplanering och bostadsutveckling från industrialismen till modern tid, med fokus på hur bostadsmiljöer påverkar människors livsvillkor. Den riktar viss kritik mot moderna förorter för bristande sociala och mänskliga kvaliteter och förespråkar mindre, integrerade bostadsområden med närhet till natur, social gemenskap och individens behov.
Ultrasonic Signal Response from Internal Manufactured Defects in Laser- Based Powder Bed Fusion (PBF-LB) Manufactured superalloys
(2026) Surendran, Anupama
Additive manufacturing (AM) is an advanced technology reshaping global product fabrication by enabling lightweight and complex structures directly from CAD models [1]. While AM provides design freedom and material efficiency, challenges remain in ensuring consistent quality, as defects such as porosity, microcracks, and lack of fusion (LOF) voids can degrade mechanical performance [7–9]. Non-destructive testing (NDT) methods are therefore critical, with X-ray Computed Tomography (XCT) and Ultrasonic Testing (UT) emerging as the most promising despite limitations of cost, speed, and geometry sensitivity [16,20]. UT, in particular, enables early detection of internal flaws without damaging the component, and recent advances such as phased array and laser-based techniques are expected to further enhance inspection capability [2,24,25]. This study evaluates the ultrasonic signal response from intentionally introduced defects in PBF-LB manufactured Alloy 247 and Inconel 939 samples. Both immersion UT and PAUT were applied to investigate the influence of defect morphology, orientation, and surface finish. Results showed that defects down to 0.4 mm could be reliably detected when oriented perpendicular to the scanning surface. Machined surfaces significantly improved defect detectability, while partially melted powder around defects increased scattering and reduced signal clarity. Among probes, the 3.25" transducer provided the most consistent response due to its larger aperture, which enhanced beam focus, signal strength, and defect detectability across varied geometries and surface conditions. Defect morphology strongly influenced detectability, with angled and roof-shaped defects showing reduced visibility compared to cylindrical or spherical ones. Comparison of inspection methods demonstrated that PAUT enhanced sensitivity and imaging in geometrically complex regions, whereas XCT provided more accurate defect characterization but with slower scan speed and higher cost. These findings highlight the importance of probe selection, surface condition, and defect morphology for developing robust in-situ inspection strategies and support the integration of PAUT and XCT as complementary methods for standardized quality control in metal additive manufacturing.
Body design of electric three-wheeler
(2026) Romell , Joakim
Electric three-wheeler manufacturer Omotion, located in Lund, Sweden, was in the process of improving the performance of their only existing vehicle model, the Omotion 2. A new vehicle model was desired in which the performance increase could be implemented. Omotion wanted to achieve a “modern” and “sporty” design which utilised the performance efficiently. Aerodynamics was therefore a concern. Included in the requirements was that the design had to have a roof over the occupants. As a roof was a necessity, how individuals enter and exit the vehicle was considered in the work. Because the work was very aesthetics driven, aesthetic trends for motorcycles and sportscars in several Western European countries were studied. Naked and adventure motorcycles were determined to be trending and consisted of features such as exposed mechanics and small complex bodywork panels. Sports cars shared similarities such as low to the ground and slightly sloped hood. A function analysis was also done as part of the prestudy and guided the concept development. The function identified were kept vague to allow for a wide variety of solutions. Concept development was done with the help of sketches, morphological matrices, CAD models, and a clay model. Concept generation was also attempted using artificial intelligence (AI) but was unsuccessful. The work resulted in a satisfactory concept despite difficulties ascertaining the aerodynamic performance. Mechanical solutions to make the concept feasible would still be developed but the mechanisms were already in use on other vehicles. With continued development of the concept, Omotion should have the ability to realise the concept within ten years
Integrated Fast Battery Charger Using an Electrically Excited Synchronous Machine-Based Drive System
(2026) Ma, Xinyu
This thesis investigates an integrated off-board fast battery charging system utilizing an Electrically Excited Synchronous Machine (EESM)-based drive topology. The aim is to reuse the existing traction inverter and machine windings as part of a DC/DC boost converter, thereby reducing system cost, volume, and component redundancy. To achieve this goal, three levels of simulation were carried out. First, an excitation-based Finite Element Analysis (FEA) in ANSYS Maxwell was per formed to determine losses and inductances of the EESM under various operating conditions. Second, a system-level co-simulation between Maxwell and ANSYS Simplorer/Simulink was conducted, in which the electromagnetic model of the machine interacted dynamically with the converter and control system. This enabled real time calculation of inductances and losses under variations in both shift angle and rotor position. Finally, a Simulink-based system simulation was carried out to analyze current ripple, torque generation, and efficiency across different frequencies. The results show that phase-shift modulation predominantly affects the current waveform and ripple behavior, while the magnetic coupling and inductance remain almost constant. Increasing the switching frequency reduces stator core losses but has minimal impact on copper losses. Overall, the proposed integrated EESM-based fast charger demonstrates high feasibility and efficiency. It achieves compact system integration, stable electromagnetic performance, and effective control of current ripple and core losses - offering a sustainable approach for future electric vehicle charging architectures.