Search for dissertations about: "David Engström"

Found 4 swedish dissertations containing the words David Engström.

2. 1. Multi-Level Lossless Phase Modulation in Liquid Crystals for High-Speed Spatial Light Modulators

   Author : David Engström; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; phase measurements; polarization; phase modulation; beam steering; Spatial light modulators; diffractive optics; ferroelectric liquid crystals;

   Abstract : The spatial light modulator (SLM) is a compact device that enables highly precise control of light propagation with low drive voltages and no moving parts. By imposing a certain phase modulation onto the incident lightwave, functions such as multi-beam steering, beam shaping, and air turbulence corrections can be achieved in realtime. READ MORE

4. 2. Exponential integrators for stochastic partial differential equations

   Author : Rikard Anton; David Cohen; Christian Engström; Stig Larsson; Annika Lang; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Stochastic partial differential equations; numerical methods; stochastic exponential integrator; strong convergence; trace formulas;

   Abstract : Stochastic partial differential equations (SPDEs) have during the past decades become an important tool for modeling systems which are influenced by randomness. Because of the complex nature of SPDEs, knowledge of efficient numerical methods with good convergence and geometric properties is of considerable importance. READ MORE

5. 3. Reliable hp finite element computations of scattering resonances in nano optics

   Author : Juan Carlos Araujo-Cabarcas; Christian Engström; David Cohen; Mats G. Larson; Jeffrey Ovall; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Scattering resonances; Helmholtz problems; pseudospectrum; Lippmann-Schwinger equation; finite element methods; nonlinear eigenvalue problems; spurious solutions;

   Abstract : Eigenfrequencies are commonly studied in wave propagation problems, as they are important in the analysis of closed cavities such as a microwave oven. For open systems, energy leaks into infinity and therefore scattering resonances are used instead of eigenfrequencies. READ MORE

6. 4. Characterisation of Aqueous Solutions, Liquid Crystals and Solid State of Non-ionic Polymers in Association with Amphiphiles and Drugs

   Author : Annika Ridell; Martin Malmsten; Sven Engström; David Attwood; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; polymer; surfactant; phase diagram; x-ray diffraction; fluorescence spectroscopy; calorimetry; PEG; cellulose ether; viscometry; cubic phase; liquid crystals; drugs; solid dispersion; Fysikalisk kemi; Physical chemistry; Fysikalisk kemi; Fysikalisk och oorganisk farmaceutisk kemi; Physical and Inorganic Pharmaceutical Chemistry;

   Abstract : Cellulose ethers and polyethylene glycols are used in drug formulations as water swelling or water soluble matrices. Polar lipids, for example monoglycerides, and surfactants can be used to solubilise hydrophobic or amphiphilic drugs and to formulate potential drug delivery vehicles such as emulsions, liposomes and cubic phases. READ MORE