Sökning: "spectral imaging"
Visar resultat 11 - 15 av 127 avhandlingar innehållade orden spectral imaging.
11. Hyperspectral imaging for in-situ applications : Methods to improve the classification of materials using hyperspectral imaging
Sammanfattning : This thesis addresses several research questions related to in-situ hyperspectral imaging systems, proposes measurement methods for more accurate imaging, and examines the impact of the methods on material classification.First, the thesis investigates the possibility of successfully calibrating a hyperspectral imaging system using a low-cost PTFE reference. LÄS MER
12. A Segmented Silicon Strip Detector for Photon-Counting Spectral Computed Tomography
Sammanfattning : Spectral computed tomography with energy-resolving detectors has a potential to improve the detectability of images and correspondingly reduce the radiation dose to patients by extracting and properly using the energy information in the broad x-ray spectrum. A silicon photon-counting detector has been developed for spectral CT and it has successfully solved the problem of high photon flux in clinical CT applications by adopting the segmented detector structure and operating the detector in edge-on geometry. LÄS MER
13. Spectral analysis in laser powder bed fusion
Sammanfattning : This thesis is about the investigation of the spectral interaction of electromagnetic radiation with metal powders. For this purpose, spectral data of powders for laser powder bed fusion processes are investigated in three papers using different techniques. LÄS MER
14. Spectral image quality and applications in breast tomosynthesis
Sammanfattning : In the 1970s, it was determined that screening mammography is an efficient tool in fighting the increasing number of women dying from breast cancer, and many countries have established screening programs since then. Mammography systems have improved substantially over the years with one of the major advances being the transition from x-ray film to digital x-ray detectors. LÄS MER
15. Spectral analysis and magnetic resonance spectroscopy
Sammanfattning : This dissertation is concerned with nonparametric approaches for spectral analysis (SA) and algorithms for magnetic resonance spectroscopy (MRS) data analysis.A method to obtain the optimal smoothing window for the class of SA methods based on local smoothing of the periodogram is proposed. LÄS MER