Sökning: "Resonance frequency"

Visar resultat 1 - 5 av 313 avhandlingar innehållade orden Resonance frequency.

  1. 1. Frequency Optimization of Vibratory Rollers and Plates for Compaction of Granular Soil

    Författare :Carl Wersäll; Stefan Larsson; Michael Mooney; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; compaction; vibratory roller; frequency; resonance; vibration; sand; gravel; soil dynamics; Byggvetenskap; Civil and Architectural Engineering;

    Sammanfattning : Vibratory rollers are commonly used for compaction of embankments and landfills. This task is time consuming and constitutes a significant part of most large construction and infrastructure projects. By improving the compaction efficiency, the construction industry would reduce costs and environmental impact. LÄS MER

  3. 2. Application of Automated Non-contact Resonance Testing for Low Temperature Behavior of Asphalt Concrete

    Författare :Abiy Bekele; Nils Ryden; Safwat Said; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Resonance testing; stiffness modulus; asphalt concrete; Non-contact excitation; Resonance frequency; Civil and Architectural Engineering; Byggvetenskap;

    Sammanfattning : Impact resonance testing is a well-documented non-destructive testing method and its applications on asphalt concrete have also been implemented successfully. The test is carried out manually by inducing an impact in order to excite the test specimen and taking measurements of the vibrational response. LÄS MER

  4. 3. Broadband Ferromagnetic Resonance Spectrometer : Instrument and Applications

    Författare :Vasyl Denysenkov; KTH; []
    Nyckelord :ferrites; thin films; ferromagnetic resonance; microwaves; FMR spectrometer; magnetic anisotropy; magnetostatic waves;

    Sammanfattning : This thesis compiles results of research in two mutuallydependent parts: 1) development of ferromagnetic resonance(FMR) spectrometer to study microwave properties offerromagnetic materials, and 2) characterization of new irongarnets: pulsed laser deposited Y3Fe5O12and Bi3Fe5O12films and Ce:Y3Fe5O12single crystal.First part describes a novelBroadbandFMRSpectrometerdesigned to characterize thin ferromagneticfilms. LÄS MER

  5. 4. Frequency comb Brillouin microscopy

    Författare :Felipe Ademir Alemán Hérnandez; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Brillouin light scattering; optics; spinwave spectroscopy; phonon spectroscopy; microscopy; Fabry-Perot interferometer; Frequency comb;

    Sammanfattning : Brillouin light scattering (BLS), an almost a century-old technique, has evolved into a powerful and versatile method to study acoustic and magnetic phenomena down to the nanometer size scale. Presently, BLS can be applied in fields as diverse as acoustics, spintronics, geosciences, and biophysics. LÄS MER

  7. 5. Detecting Inclusions in a Silicone Rubber Phantom Using Standing Lamb Waves and Multiple Frequency Footprints

    Författare :Ulf G Jonsson; Britt Andersson; Olof A Lindahl; Jacques Ohayon; Umeå universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Piezoelectric; Silicone rubber; Impedance; Resonance; Lamb waves; Phantom; Electronics; elektronik;

    Sammanfattning : The thesis deals with one major question: is it possible, using one piezoelectric sensor/vibrator, to detect a hard inclusion in a silicone rubber phantom? The question was approached with an open mind and the task was subdivided into three clearly identifiable parts: characterization of the piezoelectric sensor/vibrator (paper I), creating a model of the visco-elastic properties of a tissue-like material (phantom) in contact with the sensor/vibrator (paper II), and to detect the presence of a hard inclusion in the phantom (paper III). All vibrations of the sensor/vibrator and phantom was modeled using a finite element method (FEM). LÄS MER