• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • Tagged with
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

3D Synthetic Aperture Imaging Using LaserUltrasonics

Zalamans, Louise January 2021 (has links)
Synthetic Aperture Focusing Technique (SAFT) is a powerful method to createfocused images of the inside of opaque samples by using delay-and-sum of acquireddata. It gives a high resolution and when using a generation laser and a detectionlaser it is also non-contact. This thesis was made at Swerim, and the aim wasto create an 3D-SAFT algorithm and to visualise the reconstructed image. Twosamples were used, both were 3D-printed with known defects that varied in sizefrom 0.05 mm to 1 mm. The defects were lined up in rows, with 10 in each row.After the algorithm was used on the acquired data from the two samples, six toeight defects were found in each row. Both samples had three rows of defects. Themeasured sizes of the defects were not exactly as the actual size but ranged a fewmillimetre too small or big compared to the real size. Overall the algorithm workswell. The resolution of the 3D images are the same as for the 2D-SAFT algorithmalready made by Swerim. As of now the 3D images may not be worth the time ittakes to process, but if a better way to visualise the data is made in the future, itwill be good to be able to see the defects in 3D.
2

On two Random Models in Data Analysis

James, David 12 January 2017 (has links)
No description available.

Page generated in 0.1293 seconds