Sökning: "cavities"

Visar resultat 6 - 10 av 213 avhandlingar innehållade ordet cavities.

1. 6. Acoustic excitation and transmission of lightweight structures

   Författare :Jonas Brunskog; Teknisk akustik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; point mobility; Lamb waves; wood.; Building construction; plate excitation; cavities; near-periodicity; nearly periodic; sound insulation; timber; structural acoustics; spatial Fourier transform; resilient device; prediction model; periodic; lightweight; ISO tapping machine; airborne noise; Building acoustics; impact noise; Byggnadsteknik;

   Sammanfattning : In order to increase our knowledge of the sound transmission and radiation processes of lightweight wall and floor structures, theoretical models are needed. Detailed models may form a valuable tool. In lightweight floor structures, impact sound insulation is perhaps the most important property to consider. LÄS MER

3. 7. Modelling of cavity partial discharges at variable applied frequency

   Författare :Cecilia Forssén; Roland Eriksson; Hans Edin; Peter H.F. Morshuis; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; partial discharges; measurements; modelling; variable frequency; cavities; disc-shaped; polycarbonate; Electric power engineering; Elkraftteknik;

   Sammanfattning : The presence of partial discharges (PD) in high voltage components is generally a sign of defects and degradation in the electrical insulation. To diagnose the condition of high voltage insulation, PD measurements is commonly used. LÄS MER

4. 8. Waves in space plasmas : Lower hybrid cavities and simple-pole distribution functions

   Författare :Anders Tjulin; Mats André; Hans Pécseli; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Space and plasma physics; space physics; plasma; waves; dispersion relations; lower hybrid cavities; Cluster; magnetosphere; Rymd- och plasmafysik; Space physics; Rymdfysik;

   Sammanfattning : Waves are a fundamental feature in many parts of physics, since they transport energy without transporting matter. This is the case also in space physics. Waves are responsible for energy transport both between different parts of space and between different particles in the space plasma. LÄS MER

5. 9. Influence of Acoustic Interaction between Cavities That Generate Cavitation Noise

   Författare :Jan Hallander; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; numerical simulation; collapse of vapour cavities; experimental studies; pressure pulses; cavitation noise; hydrodynamics; cavitation; bubbles; cavitating flows;

   Sammanfattning : The thesis concerns high frequency cavitation noise generated by marine propellers, for example. The collapse of a cavity is forced by the surrounding pressure which comprises the pressure in the undisturbed flow, the pressure disturbance associated with the local non-cavitating flow and, finally, the pressure disturbance from the presence and motion of neighbouring cavities. LÄS MER

7. 10. From Macroscopic to Microscopic Dynamics of Superconducting Cavities

   Författare :Anirban Bhattacharyya; Vitaliy Goryashko; Volker Ziemann; Roger Ruber; Jean Delayen; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; superconducting cavity; superconductivity; self-excited loop; Ginzburg-landau; vortex; optimization; quality factor; microwave; Fysik med inriktning mot elementarpartikelfysik; Physics with specialization in Elementary Particle Physics;

   Sammanfattning : Superconducting (SC) radio frequency (RF) cavities are at the heart of many large-scale particle accelerators such as the European Spallation Source (ESS), the X-ray Free Electron Laser (XFEL), the Linac Coherent Light Source (LCLS)-II and the proposed International Linear Collider (ILC). The SC cavities are essentially resonant structures with very high intrinsic quality factors (Q0) of the order of 1010. LÄS MER