Sökning: "periodic"

Visar resultat 11 - 15 av 599 avhandlingar innehållade ordet periodic.

  1. 11. Studies of periodic excitation of a turbulent separation bubble

    Författare :Astrid Herbst; KTH; []
    Nyckelord :boundary layer; turbulent separation; periodic forcing; direct numerical simulation;

    Sammanfattning : .... LÄS MER

  3. 12. On the use of periodic operation for improvning chemical processes

    Författare :Lennart Vamling; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; periodic operation; di-; ammonia; and triethanolamine production; ethylene oxide; zeolites; Mono-; yield; adiabatic packed-bed reactor; selectivity;

    Sammanfattning : In this thesis, some methods of improving the product distribution from chemical processes are compared. The first two parts contain an experimental investigation of how the product distribution of a process is influenced by the choice of catalyst. LÄS MER

  4. 13. Fundamental Bounds on Performance of Periodic Electromagnetic Radiators and Scatterers

    Författare :Andrei Ludvig-Osipov; B. Lars G. Jonsson; Christophe Caloz; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Q-factor; bandwidth; antenna arrays; periodic structures; physical bounds; physical limitations; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : In this thesis, the optimal bandwidth performance of periodic electromagnetic radiators and scatterers is studied. The main focus is on the development and application of methods to obtain fundamental physical bounds, relating geometrical parameters, frequency bandwidth, efficiency and radiation characteristics of periodic electromagnetic structures. LÄS MER

  5. 14. 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

  7. 15. 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