Search for dissertations about: "cavity noise"

Showing result 21 - 25 of 55 swedish dissertations containing the words cavity noise.

2. 21. Mid- and near-infrared NICE-OHMS : techniques for ultra-sensitive detection of molecules in gas phase

   Author : Thomas Hausmaninger; Ove Axner; Kyle Crabtree; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; spectrometry; NICE-OHMS; trace gas detection; acetylene; methane; isotopologues; near-infrared; mid-infrared; shot-noise; optical parametric oscillator; teknisk fysik med inriktningen mikrosystemteknik; engineering science with specialization in microsystems technology;

   Abstract : Noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS) is a technique for ultra-sensitive detection of molecular absorption and dispersion. For highest performance, the technique combines cavity enhancement (CE) with frequency modulation (FM); while the former increases the effective interaction length between the light and the analyte by several orders of magnitudes, the latter removes the in-coupling of 1/f noise and makes the signals background free. READ MORE

4. 22. Microwave measurement techniques for industrial process monitoring and quality control

   Author : Johan Nohlert; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; powder; matched filter; fluidised bed; parameter estimation; cavity resonator; signal detection; finite element method; microwave measurement;

   Abstract : Process monitoring and quality control by sensor measurements are essential for the automatisation and optimisation of many industrial manufacturing processes. This thesis is concerned with microwave sensing, which is a measurement modality with potential to improve the in-line sensing capabilities in several industries. READ MORE

5. 23. Advanced Fluid-Structure Interaction Modelling and Simulation for Aerospace Applications

   Author : Stefan Nilsson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aeroacoustics; Hybrid RANS-LES; CSD; cavity flow; aeroelastics; CFD; FSI;

   Abstract : Numerical fluid-structure interaction (FSI) methods for the prediction of aeroelastic phenomena are important within aerospace. The continuous development of computer technologies has enabled the use of more advanced FSI methods. The use of advanced methods has the potential to provide more accurate predictions. READ MORE

6. 24. Cavitation Mechanisms Related to Erosion Studies on Kaplan Turbines, Foils, and Propellers

   Author : Mikael Grekula; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cavitation; experimental studies; cavitation erosion; cavitation mechanisms; hydrodynamics; cavitation noise; cavitation assessment;

   Abstract : The overall aim of this thesis work is to study cavitation behaviours related to erosion. The focus is on processes of observable scale, i.e. the process prior to the micro scale level at which the actual damage is generated. READ MORE

7. 25. Continuous-filtering Vernier spectroscopy

   Author : Chuang Lu; Aleksandra Foltynowicz; Ove Axner; Wei Ren; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; spectroscopy; spectrometer; laser; optical frequency comb; optical cavity; NIR; MIR; flame; robust; time resolution; spectrum; fysik; Physics;

   Abstract : Continuous-filtering Vernier spectroscopy (CF-VS) is a laser-based detection technique that combines the broad spectral coverage of an optical frequency comb (OFC) with the enhanced interaction length provided by an optical cavity. The resonances of the cavity filter the OFC to a small group of comb modes that probe the transitions of the species present in the cavity. READ MORE