Search for dissertations about: "porous wave"

Showing result 1 - 5 of 17 swedish dissertations containing the words porous wave.

2. 1. Push the limitations of crystal structure determination by 3D electron diffraction : From inorganic porous materials to biomolecules

   Author : Jingjing Zhao; Xiaodong Zou; Hongyi Xu; Tim Grüne; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; electron crystallography; 3D electron diffraction; cryo-EM specimen preparation; structure determination; porous materials; biomolecules; fysikalisk kemi; Physical Chemistry;

   Abstract : Structure elucidation is fundamental to understanding the chemical and physical properties of a material. Three-dimensional electron diffraction (3D ED) has shown great power for structure determination of nanometer- or submicrometer-sized crystals that are either too small or too complex for X-ray diffraction. READ MORE

4. 2. A study of tailoring acoustic porous material properties when designing lightweight multilayered vehicle panels

   Author : Eleonora Lind Nordgren; Peter Göransson; Olivier Dazel; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; porous material; optimization; Biot theory; acoustic wave propagation;

   Abstract : The present work explores the possibilities of adapting poro-elastic lightweight acoustic materials to specific applications. More explicitly, a design approach is presented where finite element based numerical simulations are combined with optimization techniques to improve the dynamic and acoustic properties of lightweight multilayered panels containing poro-elastic acoustic materials. READ MORE

5. 3. Wave Splitting and Effective Boundary Conditions for Structural Elements

   Author : Martin Johansson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; approximate boundary condition; Mindlin plate; Timoshenko beam; thin plates; cylindrical coordinates; series approximation; wave splitting; dispersion; fluid-loaded plate; Biot;

   Abstract : The subject of this thesis is twofold. The first part concerns the wave splitting of structural elements. The second part concerns approximate boundary conditions for fluid-loaded thin plates. Wave splitting is a mathematical tool for the formulation of scattering problems in the time domain that aims at solving inverse problems, e. READ MORE

6. 4. Wave Modelling Techniques for Medium and High Frequency Vibroacoustic Analysis Including Porous Materials

   Author : Hao Liu; Svante Finnveden; Ines Lopez Arteaga; Mohamed Ichchou; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : Numerical methods based on wave modelling are explored for the vibroacoustic analysis of wave propagation, sound transmission and interior noise in vehicles and buildings at medium and high frequencies. The presence of sound absorbing porous materials in practical engineering structures is also considered. READ MORE

7. 5. Hierarchical finite element modelling of Biot's equations for vibro-acoustic modelling of layered poroelastic media

   Author : Nils-Erik Hörlin; Peter Göransson; Frank Ihlenburg; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering physics; finite element; hierarchical; Biot; porous material; vibro-acoustic; Teknisk fysik; Engineering physics; Teknisk fysik;

   Abstract : This thesis concerns three-dimensional finite element modelling of Biot's equations for elasto-acoustic modelling of wave propagation in layered media including porous elastic materials. The concept of hierarchical (p-version) finite elements are combined with various weak forms of Biot's equations. READ MORE