Search for dissertations about: "optical sensing"

Showing result 1 - 5 of 199 swedish dissertations containing the words optical sensing.

  1. 1. Mid-infrared photonic devices for on-chip optical gas sensing

    Author : Floria Ottonello Briano; Kristinn B. Gylfason; Delphine Marris-Morini; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; ENGINEERING AND TECHNOLOGY; ENGINEERING AND TECHNOLOGY; mid-infrared; mid-IR; photonics; silicon photonics; gas sensing; optical sensing; optical gas sensing; spectroscopy; absorption; dispersion; carbon dioxide; CO2; CO2 sensing; trace gas; ethanol sensing; alcohol sensing; waveguide; photonic waveguide; ring resonator; nanowire; nanoheater; emitter; thermal source; bolometer; microbolometer; thermal detector; high frequency; 3 omega method; plasmonic; platinum; Kanthal; silicon-on-insulator; micro-electro-mechanical systems MEMS ; microfabrication; microsystems; microtechnology; nanotechnology; Optics and Photonics; Optik och fotonik; Electrical Engineering; Elektro- och systemteknik;

    Abstract : Gas detection is crucial in a wide range of fields and applications, such as safety and process control in the industry, atmospheric sciences, and breath diagnostics. Optical gas sensing offers some key advantages, compared to other sensing methods such as electrochemical and semiconductor sensing: high specificity, fast response, and minimal drift. READ MORE

  2. 2. Cavity enhanced optical sensing

    Author : Isak Silander; Ove Axner; Aleksandra Foltynowicz; Jong Chow; Umeå universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Optical resonators; Fiber Laser; Parametric oscillators; Optical frequency comb; Infrared; Spectroscopy heterodyne; Spectroscopy molecular; Absorption; Dispersion; Lineshapes; Optical standards and testing; Refractivety measurements;

    Abstract : An optical cavity comprises a set of mirrors between which light can be reflected a number of times. The selectivity and stability of optical cavities make them extremely useful as frequency references or discri­mi­nators. READ MORE

  3. 3. Remote Sensing of Urbanization and Environmental Impacts

    Author : Jan Haas; Yifang Ban; Costas Cartalis; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Remote Sensing; Urbanization; Land Use Land Cover LULC ; Environmental Impact; Landscape Metrics; Ecosystem Services; Geodesy and Geoinformatics; Geodesi och geoinformatik; Geomatik; Geomatics;

    Abstract : This thesis aims to establish analytical frameworks to map urban growth patterns with spaceborne remote sensing data and to evaluate environmental impacts through Landscape Metrics and Ecosystem Services. Urbanization patterns at regional scale were evaluated in China's largest urban agglomerations and at metropolitan scale in Shanghai, Stockholm and Beijing using medium resolution optical satellite data. READ MORE

  4. 4. Remote Sensing of Urbanization and Environmental Impacts

    Author : Jan Haas; Yifang Ban; Lars Eklund; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Remote Sensing; Classification; Land Use Land Cover; Support Vector Machine; Random Forest; Urbaniztion; Environmental Impact; Landscape Metrics; Ecosystem Services; Geomatik; Geomatics; Land Use Land-Cover; Urbanization;

    Abstract : The unprecedented growth of urban areas all over the globe is nowadays maybe most apparent in China having undergone rapid urbanization since the late 1970s. The need for new residential, commercial and industrial areas leads to new urban regions challenging sustainable development and the maintenance and creation of a high living standard as well as the preservation of ecological functionality. READ MORE

  5. 5. Integration of graphene into MEMS and NEMS for sensing applications

    Author : Xuge Fan; Frank Niklaus; Peter Steeneken; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; Micro-electromechanical systems MEMS ; Nano-electromechanical systems NEMS ; heterogeneous 3D integration; Graphene; single-layer graphene; double-layer graphene; bilayer graphene; chemical vapor deposition CVD ; suspended graphene beams; suspended graphene membranes; doubly clamped; fully clamped; silicon on insulator SOI ; vapor hydrofluoric acid VHF ; Young’s modulus; built-in stress; built-in tension; piezoresistivity; gauge factor; accelerometer; resonators; electromechanical sensing; advanced transducers; humidity; gas sensing; sensitivity; CO2 sensing; graphene grain boundary; line defects; optical microscopy; wire bonding; Electrical Engineering; Elektro- och systemteknik;

    Abstract : This thesis presents a novel approach to integrate chemical vapor deposition (CVD) graphene into silicon micro- and nanoelectromechanical systems (MEMS/NEMS) to fabricate different graphene based MEMS/NEMS structures and explore mechanical properties of graphene as well as their applications such as acceleration sensing, humidity sensing and CO2 sensing. The thesis also presents a novel method of characterization of CVD graphene grain boundary based defects. READ MORE