Sökning: "Buckling"

Visar resultat 11 - 15 av 98 avhandlingar innehållade ordet Buckling.

1. 11. Zinc Oxide Bulk and Nanorods

   Författare :Peter Klason; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; zinc oxide; Schottky contact; buckling; annealing; semiconductor growth; ion implantation; photoluminescence; nanorods;

   Sammanfattning : Zinc Oxide (ZnO) has many promising properties for optoelectronics, sensor applications, transparent electronics etc. To mention a few, ZnO has a large exciton binding energy (60 meV at room temperature) and a direct wide bandgap energy of 3.37 eV. In addition, ZnO is piezoelectric and shows more resistance to radiation damage than Si and GaN. LÄS MER

3. 12. Vibration-based Assessment of Tensegrity Structures

   Författare :Nasseradeen Ashwear; Eriksson Anders; Thomas Abrahamsson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tensegrity; Pre-stress; Vibration; Health monitoring; Buckling; Temperature effect; Vibration health monitoring VHM; Optimization; Engineering Mechanics; Teknisk mekanik;

   Sammanfattning : Vibration structural health monitoring (VHM) uses the vibration properties to evaluate many civil structures during the design steps, building steps and service life.The whole function, expressed by stiffness and frequencies of tensegrity structures are primarily related to the level of pre-stress. LÄS MER

4. 13. Vibration Frequencies as Status Indicators for Tensegrity Structures

   Författare :Nasseradeen Ashwear; Anders Eriksson; Karl-Gunnar Olsson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tensegrity; Pre-stress; Vibration; Health monitoring; Buckling; Temperature effect; Vibration health monitoring VHM; Tensegritet; Förspänning; Vibration; Hälsokontroll; Knäckning; Temperatureffekt; Vibrationsbaserad hälsokontroll; Engineering Mechanics; Teknisk mekanik;

   Sammanfattning :  Applications of vibration structural health monitoring (VHM) techniques are increasing rapidly. This is because of the advances in sensors and instrumentation during the last decades. VHM uses the vibration properties to evaluate many civil structures during the design steps, building steps and service life. LÄS MER

5. 14. Investigations of unconventional marine structures by the finite element method

   Författare :Mats Heder; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; OBO-vessels; hull strength; stiffened panel; finite element method; passenger ship; thermal stress; buckling; residual strength;

   Sammanfattning : .... LÄS MER

7. 15. Simulation of dynamic instabilities during high rate deformation of ductile bars and plates

   Författare :Kristina Nilsson; Mekanik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; numerical simulation; non-linear; wave propagation; multiple necking; necking; buckling; fracture; Mechanical engineering; Maskinteknik; finite elements; cohesive elements; dynamic; J2-flow theory; J2-deformation theory; viscoplastic; background inertia;

   Sammanfattning : In this thesis, some of the phenomena occurring in plates and cylindrical bars subjected to dynamic loading are investigated. Numerical simulations using a dynamic finite element code are performed for a number of different sized specimens with various initial surface imperfections. Typically imposed loading velocities are in the range 10m/s.. LÄS MER