Sökning: "periodic surfaces"

Visar resultat 1 - 5 av 54 avhandlingar innehållade orden periodic surfaces.

1. 1. Analysis of Planar and Circular Cylindrical Multilayer Structures with Application to Soft and Hard Surfaces

   Författare :Zvonimir Sipus; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; antennas; periodic surfaces; integral equations; approximate boundary conditions; soft and hard surfaces; Green s functions; corrugated surfaces; moment method; periodic metal strips; multilayer structures; EFIE; microstrip antennas; spectral domain analysis; group representation theory; strip scatterers;

   Sammanfattning : This thesis deals with the analysis of planar and circular cylindrical multilayer structures, such as strip-loaded dielectric layers, corrugated surfaces and microstrip antennas. In particular, we study corrugations and strip-loaded grounded dielectric slabs when they are used to realize soft and hard surfaces. LÄS MER

3. 2. On the analysis of soft surfaces, frequency selective surfaces and con­formal antennas

   Författare :Silvia Raffaelli; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; array; microstrip; antenna; dual-frequency; corrugated surface; multi-layer structure; periodic; horn; finite difference time domain; method of moments; spectral domain analysis; infinite;

   Sammanfattning : .... LÄS MER

4. 3. Analysis of Conformal Antennas and Periodic Structures

   Författare :Silvia Raffaelli; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; method of moments; microstrip; corrugated surface; horn; Floquet; array; periodic; multilayer structure; finite difference time domain; dual-frequency; infinite; spectral domain analysis; conformal antenna;

   Sammanfattning : In the last decades much attention has been paid to the design of high-performance antennas. Accurate control of the radiation properties is very important in electromagnetic engineering applications. LÄS MER

5. 4. Atomistic simulations of structural and dynamical properties of liquids under geometric constraints

   Författare :Lorenzo Agosta; Alexander Lyubartsev; Marialore Sulpizi; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; liquid; contraint; TiO2; surfaces; bio-inorganic; molecular dynamic; ab-initio; tight-binding; DFT; metadynamic; free energy; nanoparticles; water; amino acids; adsorption; mesophases; hexatic; smectic; triply periodic network; Fddd; fysikalisk kemi; Physical Chemistry;

   Sammanfattning : The statistical-mechanical description of liquids represents a formidable problem in physic due to the absence of the analytical theory of the liquid state. Atomistic simulations represent a unique source of information in this respect and can be implemented in order address macroscopically measurable liquid properties, including its structure and dynamics, based on the information of the interactions between its constituent molecules. LÄS MER

7. 5. Periodic Structures with Higher Symmetries: Analysis and Applications

   Författare :Fatemeh Ghasemifard; Martin Norgren; Oscar Quevedo-Teruel; Guido Valerio; Stefano Maci; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; periodic structures; higher symmetries; dispersion analysis; mode matching; generalized Floquet theorem; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : In this thesis, periodic structures with higher symmetries are studied. Their wave propagation characteristics are investigated and their potential applications are discussed. Higher-symmetric periodic structures are described with an additional geometrical operation beyond a translation operator. LÄS MER