Sökning: "ultrasonic"

Visar resultat 1 - 5 av 195 avhandlingar innehållade ordet ultrasonic.

1. 1. Ultrasonic Fluid and Cell Manipulation

   Författare :Mathias Ohlin; Martin Viklund; Hans Hertz; Peter Glynne-Jones; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; 3D cell culture; Acoustic streaming; Acoustofluidics; Cell manipulation; High-resolution imaging; Multi-well; Microplate; Natural killer cell; Piezo; Radiation force; Solid tumor; Solubilization; Spheroid; Standing wave; Temperature control; Transducer; Trapping; Ultrasonic; Fysik; Physics; Biological Physics; Biologisk fysik;

   Sammanfattning : During the last decade, ultrasonic manipulation has matured into an important tool with a wide range of applications, from fundamental cell biological research to clinical and industrial implementations. The contactless nature of ultrasound makes it possible to manipulate living cells in a gentle way, e.g. LÄS MER

3. 2. Ultrasonic measurement principles : modeling, identification, and parameter estimation

   Författare :Jesper Martinsson; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Industrial Electronics; Industriell elektronik;

   Sammanfattning : This thesis presents contributions within the fields of ultrasonic modeling and measurement technology, with focus on solutions to difficult modeling and measurement problems. The work is divided into two categories: 1) processing of measurements obtained under non-ideal conditions, such as unsynchronized, distorted, and superimposed signals; 2) estimating acoustic models and parameters from materials, fluids, fluid mixtures, and thin-layered structures. LÄS MER

4. 3. Non-destructive measurement of near-surface cracks in railheads : with focus on ultrasonic inspections

   Författare :Rayendra Anandika; Jan Lundberg; Paul Wilcox; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rail inspection; phased array; ultrasonic testing; eddy current testing; surface cracks; non-destructive testing; NDT; railway; condition monitoring; Drift och underhållsteknik; Operation and Maintenance;

   Sammanfattning : Near-surface cracks in railhead that caused by rolling contact fatigue (RCF) is one of a kind rail defects that degrade rail track quality. Dependent on the trail load, the cracks can reach to severe level quickly. LÄS MER

5. 4. Nonlinear Interaction Between Ultrasonic Waves and Cracks and Interfaces

   Författare :Milan Poznic; Leif Kari; Bruce Drinkwater; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ultrasonic waves; crack; modulation; rough interface; partially closed; surface-breaking; fluid-filled; Acoustics; Akustik;

   Sammanfattning : The subject of this thesis is the development of new ultrasound inspection techniques for detection of cracks that are smaller than the wavelength of the inspecting wave and the characterization of cracks in fluid-filled pipes as either surface-breaking or subsurface. The spectrum of the scattered field of a partially closed crack comprises harmonic components not expected to be found in the case of linear scatterers such as pores or inclusions. LÄS MER

7. 5. An ultrasonic density measurement technique : performance, thermal effects, experimental validations, and modeling

   Författare :Jan van Deventer; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Industriell elektronik; Industrial Electronics;

   Sammanfattning : This licentiate thesis addresses the idea of measurement of the density of liquids using sound. The thesis can be dived into three sections: 1. An introduction that presents the need for the research and its future application into an ultrasonic mass flow meter. 2. LÄS MER