Search for dissertations about: "resonant ultrasound"

Found 3 swedish dissertations containing the words resonant ultrasound.

  2. 1. Ultrasonic Arrays for Sensing and Beamforming of Lamb Waves

    Author : Marcus Engholm; Tadeusz Stepinski; Paul D. Wilcox; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; imaging; array processing; guided waves; Lamb waves; dispersive waves; multi-modal waves; spatial filtering; mode suppression; resonant ultrasound; transducer design; direction of arrival estimation; adaptive beamforming; Signal processing; Signalbehandling; Electronic measurement and instrumentation; Elektronisk mät- och apparatteknik;

    Abstract : Non-destructive testing (NDT) techniques are critical to ensure integrity and safety of engineered structures. Structural health monitoring (SHM) is considered as the next step in the field enabling continuous monitoring of structures. READ MORE

  4. 2. Static and time-dependent mechanical behaviour of preserved archaeological wood : Case studies of the seventeenth century warship Vasa

    Author : Alexey Vorobyev; Kristofer Gamstedt; Eiichi Obataya; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; archaeological wood; compression test; cubic samples; elastic constants; oak wood; barrelling formation; quasi-static loading; resonant ultrasound spectroscopy RUS ; Vasa ship; creep; 3D laser scanning; Time-dependent behaviour;

    Abstract : Wooden objects have been widely used in the history of humanity and play an important role in our cultural heritage. The preservation of such objects is of great importance and can be a challenging task. This thesis investigates the static and time-dependent mechanical behaviour of archaeological oak wood from the Vasa warship. READ MORE

  5. 3. Assessment of Long-Term Losses in Prestressed Concrete Structures - Application for Nuclear Reactor Containments

    Author : Peter Lundqvist; Avdelningen för Konstruktionsteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; KstrConcrete; Nuclear reactor containments; prestressed concrete; prestress losses; bonded tendons; creep; shrinkage; relaxation; prediction models; resonance frequency; acoustoelasticity.;

    Abstract : Most nuclear reactors, both in Sweden and worldwide, are enclosed by a prestressed concrete containment. The main purpose of the containment is to prevent any radioactive discharge to the environment in the event of a major internal accident. READ MORE