Sökning: "Nondestructive Evaluation"

Visar resultat 11 - 15 av 17 avhandlingar innehållade orden Nondestructive Evaluation.

  1. 11. Tools for ultrasonic characterization of layered media

    Författare :Fredrik Hägglund; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Signalbehandling; Signal Processing;

    Sammanfattning : Many industries are dealing with composite materials and multi-layered structures of various materials. Errors in the manufacturing process may lead to defects in the final product, and hence, avoiding imperfections is crucial. The importance of repeated quality assurance online is therefore essential during the process. LÄS MER

  3. 12. Non-contact surface wave measurements on pavements

    Författare :Henrik Bjurström; Nils Rydén; Björn Birgisson; Jinying Zhu; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; seismic testing; asphalt concrete; dynamic modulus; non-contact measurements; rolling measurements; surface waves; Lamb waves; MEMS microphones; Byggvetenskap; Civil and Architectural Engineering;

    Sammanfattning : In this thesis, nondestructive surface wave measurements are presented for characterization of dynamic modulus and layer thickness on different pavements and cement concrete slabs. Air-coupled microphones enable rapid data acquisition without physical contact with the pavement surface. LÄS MER

  4. 13. Modelling of Radiographic Testing to Derive a Detection Positioning and Sizing Algorithm for Pore Defects

    Författare :Erik Lindgren; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : When laser welding light weight materials, e.g. aluminium and titanium based alloys, small sub-millimeter pore defects occasionally forms. Due to their small sizes, less than some 0. LÄS MER

  5. 14. Failure Monitoring and Asset Condition Assessment in Water Supply Systems

    Författare :Dalius Misiunas; Industriell elektroteknik och automation; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mechanical engineering; reglerteknik; robotteknik; Automatiska system; Water supply; failure; detection; monitoring; location; bursts; hydraulics; leakage; asset management; condition assessment; pipelines; pipe networks; Automation; control engineering; robotics; vacuum technology; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik;

    Sammanfattning : In this thesis, different aspects of failure management in urban water supply systems are discussed. As assets are getting older, the number of pipe failures is increasing and an efficient failure management strategy becomes important. LÄS MER

  7. 15. Guided Elastic Waves along Periodically Corrugated Structures

    Författare :Ahmed M. A. El-Bahrawy; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : The present thesis consider time-harmonic surface and guided elastic waves propagating along periodically corrugated structures. The problems discussed deal with various configurations where the surfaces are sinusoidally - singly or doubly - periodic, and the interest is focused on investigating the roots of the dispersion relations and in particular the stopband and cross-over resonances. LÄS MER