Sökning: "natural frequency analysis"

Visar resultat 16 - 20 av 314 avhandlingar innehållade orden natural frequency analysis.

  1. 16. Homogenization of some new mathematical models in lubrication theory

    Detta är en avhandling från Luleå : Luleå tekniska universitet

    Författare :Afonso Fernando Tsandzana; Luleå tekniska universitet.; [2016]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; lubrication theory; homogenization theory; Reynolds equation; cavitation; surfaces roughness; Stokes equation; Matematik; Mathematics;

    Sammanfattning : We consider mathematical modeling of thin film flow between two rough surfaces which are in relative motion. For example such flows take place in different kinds of bearings and gears when a lubricant is used to reduce friction and wear between the surfaces. LÄS MER

  2. 17. Asymptotics of the Scenery Flow and Properties of the Fourier Dimension

    Detta är en avhandling från Luleå : Luleå tekniska universitet

    Författare :Fredrik Ekström; Lunds universitet.; Lund University.; [2016-10-11]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis is about the scenery flow and the Fourier dimension.The scenery flow is a semiflow on the space of Borel probability measures on the interval [-1, 1] that have the origin in their support. The flow acts on such a measure by enlarging it, restricting it back to [-1, 1] and renormalising it to a probability measure. LÄS MER

  3. 18. Electromagnetic dispersion modeling and analysis for HVDC power cables

    Detta är en avhandling från Växjö

    Författare :Stefan Gustafsson; Linnéuniversitetet.; [2012]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; HVDC power cables; electromagnetic model; TDR measurement; sensitivity analysis; dispersion relation; propagation constant; low-frequency asymptotics;

    Sammanfattning : Derivation of an electromagnetic model, regarding the wave propagation in a very long (10 km or more) High Voltage Direct Current (HVDC) power cable, is the central part of this thesis. With an existing “perfect” electromagnetic model there are potentially a wide range of applications. LÄS MER

  4. 19. Multivariate non-invasive measurements of skin disorders

    Detta är en avhandling från Umeå : Kemi

    Författare :Josefina Nyström; Umeå universitet.; [2006]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Multivariate Data Analysis; Non-invasive techniques; Clinical studies; Principal Component Analysis; Partial Least Squares Discriminant Analysis; Wilcoxon Signed Rank Sum Test; Near-InfraRed spectroscopy; Frequency Bio Impedance Analysis of whole body; Laser Doppler Imaging; Digital Colour Photography; NATURAL SCIENCES Chemistry Analytical chemistry; NATURVETENSKAP Kemi Analytisk kemi;

    Sammanfattning : The present thesis proposes new methods for obtaining objective and accurate diagnoses in modern healthcare. Non-invasive techniques have been used to examine or diagnose three different medical conditions, namely neuropathy among diabetics, radiotherapy induced erythema (skin redness) among breast cancer patients and diagnoses of cutaneous malignant melanoma. LÄS MER

  5. 20. On MIMO Systems and Adaptive Arrays for Wireless Communication Analysis and Practical Aspects

    Detta är en avhandling från Uppsala : Signaler och System

    Författare :Mattias Wennström; Uppsala universitet.; [2002]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Systemteknik; antenna array; calibration; MIMO system; flat fading; non-linear amplifier; switched parasitic antenna; analog beamformer; adaptive antenna testbed; Systemteknik; TECHNOLOGY Information technology Systems engineering; TEKNIKVETENSKAP Informationsteknik Systemteknik; Signal Processing; signalbehandling;

    Sammanfattning : This thesis is concerned with the use of multiple antenna elements in wireless communication over frequency non-selective radio channels. Both measurement results and theoretical analysis are presented. New transmit strategies are derived and compared to existing transmit strategies, such as beamforming and space-time block coding (STBC). LÄS MER