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Visar resultat 1 - 5 av 47 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Numerical modelling of time-dependent metamaterials with the FDTD method

    Författare :Sergey Novozhilov; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; FDTD; time-dependent media; numerical modelling; computational electrodynamics; metamaterials;

    Sammanfattning : Metamaterials are artificial materials, usually composed of so-called meta-atoms, with electromagnetic properties which cannot be found in naturally occurring materials. In this work we study the properties of time-dependent metamaterials (meaning that their electromagnetic properties are varying with time), as well as their potential applications. LÄS MER

  3. 2. Dosimetry of Local Radio Frequency Exposure

    Författare :Rudolf Kopecky; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; subgridding; FDTD; rats; head; SAR; dosimetry; inner ear labyrinth; mobile phone;

    Sammanfattning : Finite-difference time-domain (FDTD) is a popularcomputational electrodynamics modelling technique. It has been widelyused, from radar cross section computations through electromagneticcompatibility investigations to modelling of electromagnetic exposurein biological tissues. LÄS MER

  4. 3. Direct and Inverse Methods for Waveguides and Scattering Problems in the Time Domain

    Författare :Erik Abenius; Per Lötstedt; Mats Gustafsson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Maxwell s equations; time-domain; FDTD; finite-element; hybrid; thin sheet; waveguide; PML; inverse scattering; adjoint; gradient-based; minimization; Beräkningsvetenskap med inriktning mot numerisk analys; Scientific Computing with specialization in Numerical Analysis;

    Sammanfattning : Numerical simulation is an important tool in understanding the electromagnetic field and how it interacts with the environment. Different topics for time-domain finite-difference (FDTD) and finite-element (FETD) methods for Maxwell's equations are treated in this thesis. LÄS MER

  5. 4. Computation of EMC Properties of Slots and Printed Circuit Boards

    Författare :Jan Carlsson; RISE; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; corrugations; crosstalk; FDTD; spectral domain; EFIE; chokes; Finite Difference Method; printed circuit board; transmission line network; EMC analysis; PCB; transmission line theory; radiated emission; Method of moments; MM; MoM; electric field integral equation; soft and hard surfaces; slot; radiated susceptibility;

    Sammanfattning : This thesis deals with the numerical solution of electromagnetic compatibility (EMC) problems for electronic systems, such as radiated emission, susceptibility and crosstalk on printed circuit boards and transmission through slots. The analysis of printed circuit boards is done by using an electric field integral equation (EFIE) expressed in the frequency domain, which is solved by using the method of moments. LÄS MER

  7. 5. Analysis of Industrial Microwave Ovens

    Författare :Magnus Sundberg; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; source model; heat transfer; moment method; finite difference time domain; TM applicator; GMT; edge diffraction; thermal simulation; MMP; FDTD; generalized multipole technique; cost function; MM; optimization; magnetron; simulated annealing; multiple multipole program; microwave heating; edge overheating; TE applicator; tunnel-oven; applicator;

    Sammanfattning : This thesis deals with the analysis and design of microwave ovens used in the food industry. Such analysis is desirable in order to optimize the performance of the ovens and to reduce the time and expenses of developing new or improved ovens. LÄS MER