Sökning: "Low-Frequency noise"

Visar resultat 16 - 20 av 103 avhandlingar innehållade orden Low-Frequency noise.

  1. 16. Innovative noise control in ducts

    Författare :Maaz Farooqui; Mats Åbom; Hans Bodén; Tamer Elnady; Jeong-Guon Ih; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Locally resonant materials; slow sound; acoustic impedance; metallic foam; low frequency noise; mufflers; lined ducts; grazing flow; flow duct; impedance eduction.; Vehicle and Maritime Engineering; Farkostteknik;

    Sammanfattning : The objective of this doctoral thesis is to study three different innovative noise control techniques in ducts namely: acoustic metamaterials, porous absorbers and microperforates. There has been a lot of research done on all these three topics in the context of duct acoustics. LÄS MER

  3. 17. Low Phase Noise GaN HEMT Oscillator Design based on High-Q resonators

    Författare :Mikael Hörberg; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; resonator coupling; reflection oscillator; MMIC; phase noise; cavity resonator; low-frequency noise; GaN HEMT; MEMS;

    Sammanfattning : The thesis considers the design and optimization of oscillators targeting low phase noise, given boundary conditions from the technology. Crucial technology figures are power capability, RF noise figure, low-frequency noise and the quality factor (Q-factor) of the resonator. LÄS MER

  4. 18. Measurement and perception of sound insulation from 20 Hz between dwellings

    Författare :Rikard Öqvist; Fredrik Ljunggren; Roger Johnsson; Anders Ågren; Berndt Zeitler; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Sound insulation; Lightweight constructions; Annoyance; Measurement uncertainty; Low frequency; Building Acoustics; Walking noise; Teknisk akustik; Engineering Acoustics;

    Sammanfattning : Population growth and urbanization are projected by the United Nations to add 2,5 billionpeople to the world’s urban population by 2050. We need to construct buildings in anunprecedented scale to meet global housing demand. Sustainable development is critical. LÄS MER

  5. 19. Electrical Noise in Colossal Magnetoresistors and Ferroelectrics

    Författare :Alvydas Lisauskas; KTH; []
    Nyckelord :low frequency noise; colossal magnetoresistance; uncooled bolometer; relaxations and electrical fluctuations in ferroelectrics;

    Sammanfattning : .... LÄS MER

  7. 20. Low frequency noise in the single electron transistor : instrumentation and experiments

    Författare :Björn Starmark; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : .... LÄS MER