Browsing NTNU Open by Author "Torgersen, Jan"
Now showing items 41-60 of 94
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High-performance stationary solar tracking through multi-objective optimization of beam-steering lens arrays
Johnsen, Håkon Jarand Dugstad; Aksnes, Astrid; Torgersen, Jan (Peer reviewed; Journal article, 2020)Beam-steering lens arrays enable solar tracking using millimeter-scale relative translation between a set of lens arrays. This may represent a promising alternative to the mechanical bulk of conventional solar trackers, ... -
Improving stress corrosion cracking behavior of AZ31 alloy with conformal thin titania and zirconia coatings for biomedical applications
Peron, Mirco; Bin Afif, Abdulla Shaikh Abdul Qader; Dadlani, Anup; Berto, Filippo; Torgersen, Jan (Peer reviewed; Journal article, 2020)Magnesium and its alloys have been widely studied as materials for temporary implant devices. However, corrosion-assisted cracking phenomena such as stress corrosion cracking (SCC) continue to prevent their mainstream use. ... -
In situ nucleation studies of ALD Copper thin films
Flaten, Andreas (Master thesis, 2020)Ettersom moderne elektroniske enheter stadig blir mindre og mer komplekse, vil ultratynne kobberfilmer med skarpe grensesnitt bli uunnværlige i fremtiden. Oppløsning på atomnivå kan oppnåes ved atom lag deponering(ALD), ... -
Investigation of Chemical Mechanical Polishing to Enhance Feature Resolution by Atomic Layer Deposition
Keilen, Maya (Master thesis, 2020)For å designe mindre og raskere elektroniske enheter, kreves det å lage strukturer på nanometer størrelse. Å øke detaljoppløsningen ved å bygge underliggende 3D strukturer av forskjellige materialer og frigjøre disse ... -
Line-focus solar concentration 10 times higher than the 2D thermodynamic limit
Johnsen, Håkon Jarand Dugstad; Miñano, Juan Carlos; Torgersen, Jan (Peer reviewed; Journal article, 2022)Line-focus solar concentrators have traditionally been limited by the 2D concentration limit due to the continuous translational symmetry in these systems. This limit is orders of magnitude lower than the 3D limit, severely ... -
Local strain energy density for the fatigue assessment of hot dip galvanized welded joints: Some recent outcomes
Peron, Mirco; Razavi, Seyed Mohammed Javad; Berto, Filippo; Torgersen, Jan; Mutignani, F (Journal article; Peer reviewed, 2017)Since in literature only data about the effect of the hot-dip galvanizing coating on fatigue behavior of unnotched specimens are available, whereas very few for notched components and none for welded joints, the aim of ... -
Local strain energy density for the fracture assessment of polyurethane specimens weakened by notches of different shape
Peron, Mirco; Razavi, Seyed Mohammed Javad; Berto, Filippo; Torgersen, Jan; Marsavina, L (Journal article; Peer reviewed, 2017)Recent studies on local stress fields in proximity of crack and notch tips have shown that Strain Energy Density (SED), averaged in a circular control volume surrounding the point of stress singularities, represents a ... -
Mg and its alloys for biomedical applications: Exploring corrosion and its interplay with mechanical failure
Peron, Mirco; Torgersen, Jan; Berto, Filippo (Journal article; Peer reviewed, 2017)The future of biomaterial design will rely on temporary implant materials that degrade while tissues grow, releasing no toxic species during degradation and no residue after full regeneration of the targeted anatomic site. ... -
Minimizing Ski Friction through Nanostructured Hydrophobic Surfaces
Madsen, Tone Hjort (Master thesis, 2018)The correlation between ski friction and a ski base surface that can enhance hydrophobicity by geometry has been investigated. A review is given of existing knowledge about the linkage between ski friction mechanisms, ... -
Mode II brittle fracture: Recent developments
Campagnolo, A; Razavi, Seyed Mohammed Javad; Peron, Mirco; Torgersen, Jan; Berto, Filippo (Journal article; Peer reviewed, 2017)Fracture behaviour of V-notched specimens is assessed using two energy based criteria namely the averaged strain energy density (SED) and Finite Fracture Mechanics (FFM). Two different formulations of FFM criterion are ... -
Modeling of Transport Phenomena in Structured Gas Diffusion Layers for Proton Exchange Membrane Fuel Cells
Svartvatn, Preben Johnsen (Master thesis, 2022)To reduce CO2 emissions and reach the ambitious goals towards a greener world, it is crucial to develop more emission-free transport sources. A promising technology for a greener automobile industry is proton-exchange membrane ... -
Modelling Thermal Effects in a Battery Driven Formula Student Race Car
Beascoechea, Asier (Master thesis, 2019)Denne masteroppgaven er skrevet som en del av enstilling i Revolve NTNU Electric Team 2019 som kjølesystem ansvarlig. Revolve NTNU er en studentorganisasjon som representerer NTNU i verdens største ingeniørkonkurranse, ... -
New approaches to solar tracking and concentration through numerical optimization of lens arrays
Johnsen, Håkon Jarand Dugstad (Doctoral theses at NTNU;2020:405, Doctoral thesis, 2020)Solar concentrators are essential for enabling several solar energy applications, including high-efficiency photovoltaic conversion and high-temperature solar thermal energy. These concentrators require accurate solar ... -
Next Generation Design of Satellite Brackets - By Using Topology Optimization and Additive Manufacturing
Sanden, Øyvind (Master thesis, 2018)This thesis has explored how topology optimization and additive manufacturing can be used to improve the resonance performance of existing mechanical components. By using a sensitivity-based optimization algorithm for ... -
Notch stress intensity factors under mixed mode loadings: An overview of recent advanced methods for rapid calculation
Peron, Mirco; Razavi, Seyed Mohammed Javad; Berto, Filippo; Torgersen, Jan (Journal article; Peer reviewed, 2017)Recently some methods for the rapid calculation of notch stress intensity factors (NSIFs) have been developed and three of them are compared in this work. First, the criteria proposed by Lazzarin et al. and Treifi et al. ... -
Notched graphite under multiaxial loading
Razavi, Seyed Mohammed Javad; Peron, Mirco; Torgersen, Jan; Berto, Filippo (Journal article; Peer reviewed, 2017)Cylindrical specimens made of polycrystalline graphite and weakened by circumferential V-notches under mixed mode I/III loading were studied in this research. Different geometries of V-notches varying the notch opening ... -
Novel Low Cost Solar Thermal Energy Concepts for Developing Countries
Johnsen, Håkon Jarand Dugstad (Master thesis, 2017)Small scale solar thermal energy devices such as solar cookers are promising solutions for remote areas where other energy sources are limited, for instance in developing countries. These devices can be used directly for ... -
On the evaluation of ALD TiO2, ZrO2 and HfO2 coatings on corrosion and cytotoxicity performances
Peron, Mirco; Cogo, Susanna; Maria, Bjelland; Bin Afif, Abdulla Shaikh Abdul Qader; Dadlani, Anup; Greggio, Elisa; Berto, Filippo; Torgersen, Jan (Peer reviewed; Journal article, 2021)Magnesium alloys have been widely studied as materials for temporary implants, but their use has been limited by their corrosion rate. Recently, coatings have been proven to provide an effective barrier. Though only little ... -
On the mechanical integrity of welded joints made by Hybrid Metal Extrusion & Bonding Mechanical and microstructure characterisation of aluminium and aluminium-steel butt welds
Sandnes, Lise (Doctoral theses at NTNU;2021:323, Doctoral thesis, 2021)This doctoral thesis is concerned with experimental studies of aluminium-aluminium and aluminium-steel butt welds made by Hybrid Metal Extrusion & Bonding (HYB). The primary objective of the work has been to evaluate the ... -
On the porosity-dependent permeability and conductivity of triply periodic minimal surface based porous media
Sauermoser, Marco; Veldurthi, Naresh Kumar; Wölfle, Christoph Hubertus; Svartvatn, Preben Johnsen; Flo Hoem, Svenn Ove; Lid, Markus Joakim; Bock, Robert; Palko, James W.; Torgersen, Jan (Journal article; Peer reviewed, 2023)With the fast development in the field of additive manufacturing, triply periodic minimal surface (TPMS) based porous media have recently found many uses in mechanical property tuning. However, there is still a lack of ...