Sökning: "non-linear response"
Visar resultat 1 - 5 av 181 avhandlingar innehållade orden non-linear response.
1. Quantum chemical calculations of non-linear optical absorption
Sammanfattning : This thesis represents a quantum chemical treatise ofvarious types of interactions between radiation and molecularsystems, with special emphasis on the nonlinear opticalprocesses of Multi-Photon Absorption and Excited StateAbsorption. Excitation energies, transition dipole moments,two-photon and three-photon tensor elements have beencalculated from different approaches; density functional theoryandab-initiotheory, employing different orders ofcorrelation treatment with the purpose to provide accuratevalues as well as evaluate the quality of the lower ordermethods. LÄS MER
2. Linear and non-linear dynamics of non-autonomous flows
Sammanfattning : Fluid flows subject to time-dependent external forces or boundary conditions are ubiquitous in biology and technical applications. Whether one considers birds flying by flapping their wings or the gust response of wind turbines, the flow is non-autonomous. LÄS MER
3. Non-Linear Vibration and Dynamic Fracture Mechanics of Bridge Cables
Sammanfattning : In the present work, the non-linear vibrations and the corresponding dynamic fracture mechanics of cables of cable-stayed bridges are studied. The cables are among the most critical components in cable-stayed bridges and there are different damage sources such as corrosion, vibration, fatigue and fretting fatigue that can significantly affect them, thereby reducing the cable’s service life and even producing their failure. LÄS MER
4. Non-linear mechanics of nanocellulose foams
Sammanfattning : There has been a growing interest in nano-fibrillar cellulose (NFC), which has been fuelled not merely by the advantages it presents in terms of strength to weight ratio and biodegradability, but also owing to the recent advances in production techniques. NFC foam is essentially a hierarchical structure, wherein nanofibrils account for the smallest scale, with the pores/cell walls forming the meso scale. LÄS MER
5. Non-linear behavior of bio-based composite : characterization and modeling
Sammanfattning : The development and application of bio-based composite materials have been frequently studied. Most of the work is done on quasi-static performance of these materials. However, these composites are highly non-linear therefore there is need for investigation of their viscelastic and viscoplastic behavior. LÄS MER