Sökning: "Atom- och molekylfysik och optik"

Visar resultat 1 - 5 av 839 avhandlingar innehållade orden Atom- och molekylfysik och optik.

  1. 1. Spectral Mammography with X-Ray Optics and a Photon-Counting Detector

    Författare :Erik Fredenberg; Mats Danielsson; Björn Cederström; Jeffrey H. Siewerdsen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; mammography; x-ray optics; photon counting; spectral shaping; spectral imaging; collimation; radiation dose; signal-to-noise ratio; quantum noise; anatomical noise; spatial resolution; x-ray flux; ; TECHNOLOGY; TEKNIKVETENSKAP; Engineering physics; Teknisk fysik; Optical physics; Optisk fysik; Other engineering physics; Övrig teknisk fysik; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik; Medical engineering; Medicinsk teknik; Radiological research; Radiologisk forskning;

    Sammanfattning : Early detection is vital to successfully treating breast cancer, and mammography screening is the most efficient and wide-spread method to reach this goal. Imaging low-contrast targets, while minimizing the radiation exposure to a large population is, however, a major challenge. LÄS MER

  3. 2. Real-time breath gas analysis of carbon monoxide : laser-based detection and pulmonary gas exchange modeling

    Författare :Ramin Ghorbani; Florian M. Schmidt; Anders Blomberg; Christoffer Boman; Staffan Schedin; Jonathan Beauchamp; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; carbon monoxide CO ; pulmonary gas exchange; computational modeling; real-time breath gas analysis; single-exhalation profile; laser absorption spectroscopy; nonlinear least-squares fitting; breath sampling; baseline level; diurnal variation; healthy population; exposure study; fysik; Physics; Physiology; fysiologi;

    Sammanfattning : Breath gas analysis is a promising approach for non-invasive medical diagnostics and physiological monitoring. Real-time, breath-cycle resolved biomarker detection facilitates data interpretation and has the potential to improve the diagnostic value of breath tests as exhalation profiles carry spatiotemporal information about biomarker origin and gas exchange in the respiratory tract. LÄS MER

  4. 3. Digital Dispersion Equalization and Carrier Phase Estimation in 112-Gbit/s Coherent Optical Fiber Transmission System

    Författare :Tianhua Xu; Sergei Popov; Gunnar Jacobsen; Jie Li; Magnus Karlsson; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Coherent transmission; chromatic dispersion; carrier phase estimation; digital signal processing; Optics; Optik; Photonics; Fotonik; SRA - ICT; SRA - Informations- och kommunikationsteknik;

    Sammanfattning : Coherent detection employing multilevel modulation format has become one of the most promising technologies for next generation high speed transmission system due to the high power and spectral efficiencies. With the powerful digital signal processing (DSP), coherent optical receivers allow the significant equalization of chromatic dispersion (CD), polarization mode dispersion (PMD), phase noise (PN) and nonlinear effects in the electrical domain. LÄS MER

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

    Författare :Floria Ottonello Briano; Kristinn B. Gylfason; Delphine Marris-Morini; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; 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; Optik och fotonik; Optics and Photonics; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : 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. LÄS MER

  7. 5. VCSEL Equivalent Circuits and Silicon Photonics Integration

    Författare :Alexander Grabowski; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; vertical-cavity surface-emitting laser; light source integration; equivalent circuit; silicon photonics; sensing; optical interconnects;

    Sammanfattning : The vertical-cavity surface-emitting laser (VCSEL) is a light source of great importance for numerous industrial and consumer products. The main application areas are datacom and sensing. LÄS MER