Sökning: "natural frequency analysis"

Visar resultat 6 - 10 av 314 avhandlingar innehållade orden natural frequency analysis.

  1. 6. Electromagnetic Dispersion Modeling and Analysis for Power Cables

    Detta är en avhandling från Växjö : Linnaeus University Press

    Författare :Stefan Gustafsson; Linnéuniversitetet.; [2014]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; power cable; electromagnetic model; dispersion relation; asymptotic analysis; sensitivity analysis;

    Sammanfattning : This thesis addresses electromagnetic wave propagation in power cables. It consists of five papers, where the three first papers are based on one and the same model, and the last two papers are based on a similar but slightly different model. LÄS MER

  2. 7. Statistical inference and time-frequency estimation for non-stationary signal classification

    Detta är en avhandling från Media-Tryck, Lund University, Sweden

    Författare :Rachele Anderson; Lunds universitet.; Lund University.; Lund University.; Lunds universitet.; Lund University.; [2019-09-09]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Non-stationary processes; stochastic modeling; inference; spectral analysis; time-frequency analysis; classification; biomedical applications; deep learning;

    Sammanfattning : En signal är en fysisk kvantitet som varierar med någon oberoende variabel, t.ex. tid eller rum, som förmedlar information. En signal vars statistiska egenskaper är konstant i tid kallas stationär, medan signaler vars egenskaper varierar med tiden kallas icke-stationära, vilket är de vanligaste i naturen. LÄS MER

  3. 8. Electric Fields for Surface Design and Chemical Analysis

    Detta är en avhandling från Linköping : Linköping University Electronic Press

    Författare :Christian Ulrich; Linköpings universitet.; Linköpings universitet.; [2008]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Electric fields; Surface design; Chemical analysis; Bipolar electrodes; Impedance spectroscopy; TECHNOLOGY Chemical engineering Chemical process and manufacturing engineering Electrochemistry; TEKNIKVETENSKAP Kemiteknik Kemisk process- och produktionsteknik Elektrokemi; NATURAL SCIENCES Chemistry Physical chemistry Chemical physics; NATURVETENSKAP Kemi Fysikalisk kemi Kemisk fysik; NATURAL SCIENCES Chemistry Physical chemistry; NATURVETENSKAP Kemi Fysikalisk kemi; NATURAL SCIENCES Chemistry Physical chemistry Surface and colloid chemistry; NATURVETENSKAP Kemi Fysikalisk kemi Yt- och kolloidkemi;

    Sammanfattning : This thesis deals with the use of electric fields for evaluation and control of chemical systems. An electric field can result in the flow of charge across an interface between a metal and a solution, by means of chemical reactions. This interplay between electricity and chemistry, i.e. LÄS MER

  4. 9. Fast Numerical Techniques for Electromagnetic Problems in Frequency Domain

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Martin Nilsson; Uppsala universitet.; Uppsala universitet.; [2003]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fast Multipole Method; Minimal Residual Interpolation; Sparse Approximate Inverse preconditioning; Method of Moments; fast solvers; iterative methods; multiple right-hand sides; error analysis; Numerical Analysis; Numerisk analys;

    Sammanfattning : The Method of Moments is a numerical technique for solving electromagnetic problems with integral equations. The method discretizes a surface in three dimensions, which reduces the dimension of the problem with one. A drawback of the method is that it yields a dense system of linear equations. LÄS MER

  5. 10. Towards Ultimate Performance of THz Heterodyne Receivers: SIS Frequency Multiplier and Wideband Passive Components

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Hawal Marouf Rashid; [2016]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Wideband passive components; distributed SIS junction; Frequency multiplier; Frequency up-converter; Hybrids; distributed SIS frequency multiplier;

    Sammanfattning : This thesis focuses on the development of advanced components for the future wideband side band separating and / or multipixel receivers for radio-astronomy with ultimate sensitivity.In this thesis, a novel frequency multiplier based on distributed superconducting tunnel (SIS) junctions has been demonstrated for the first time, taking advantage of the extreme inherent nonlinearity of such device. LÄS MER