Sökning: "Vertical excitation"

Visar resultat 1 - 5 av 27 avhandlingar innehållade orden Vertical excitation.

1. 1. Vibration discomfort due to multi-axis excitation

   Författare :Andi Rahadiyan Wijaya; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Teknisk akustik; Engineering Acoustics;

   Sammanfattning : This licentiate thesis focuses on vibration discomfort due to multi-axis excitation. It is based on three studies; the first two studies were conducted in a laboratory environment using motion platform and utilizing sinusoidal signals, and the last study was a field study that utilized a fork lift truck on an artificial test track with built in obstacles that allowed controlled transient vibration excitation. LÄS MER

3. 2. Dynamic modelling and analysis of vertical machines

   Författare :Erik Synnegård; Matti Rantatalo; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Datorstödd maskinkonstruktion; Computer Aided Design;

   Sammanfattning : Since Sweden’s hydropower plants are getting old and operating conditions have changed, there is a need for simulation tools to predict the functionality, durability and needs for maintenance. Also for breakdowns and major revisions, there is a benefit if dynamical problems could be predicted through simulations. LÄS MER

4. 3. Electron beam profile measurements and emittance manipulation at the MAX-laboratory

   Författare :Åke Andersson; Lunds universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; optics; quantum excitation; emittance; synchrotron radiation; electron beam; lattice; Accelerator; storage ring; diffraction; Physics; Fysik;

   Sammanfattning : The emittances of the electron beams at the MAX-laboratory accelerator system have been studied. Apart from the build-up of the diagnostic tools for precise determination of the beam spatial profiles, the objectives have been: a) to verify the accelerator design emittances at low currents and to try to determine the emittances also at high currents; b) to investigate possibilities to manipulate the emittances. LÄS MER

5. 4. Modelling of wheel/rail interaction considering roughness and discrete irregularities

   Författare :Astrid Pieringer; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; roughness; non-Hertzian contact; railway noise; vertical wheel rail interaction; time domain; discrete irregularities;

   Sammanfattning : The interaction between wheel and rail is the predominant source of noise emission from railway operations in a wide range of conventional speeds. On the one hand, this wheel/rail noise concerns rolling noise and impact noise caused by the vertical interaction excited by roughness and discrete irregularities of the wheel/rail running surfaces, respectively. LÄS MER

7. 5. Time-domain modelling of high-frequency wheel/rail interaction

   Författare :Astrid Pieringer; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wheel rail interaction; railway noise; roughness; time domain; frictional instability; discrete irregularities; transient contact; non-Hertzian contact;

   Sammanfattning : The interaction between wheel and rail is the predominant source of noise emission from railway operations in a wide range of conventional speeds. On the one hand, this wheel/rail noise concerns rolling noise and impact noise caused by the vertical interaction excited by roughness and discrete irregularities of the wheel/rail running surfaces, respectively. LÄS MER