Sökning: "noise techniques"

Visar resultat 6 - 10 av 437 avhandlingar innehållade orden noise techniques.

  1. 6. Large Eddy Simulation for the Analysis of Supersonic Jet Noise Suppression Devices

    Författare :Markus Olander Burak; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluidic injection; mixer-ejector; jet noise; Kirchhoff; forward flight effects; LES; acoustic liner; supersonic turbulent jets; broadband time-domain impedance boundary condition; chevrons; shock-associated noise; CAA; aeroacoustics;

    Sammanfattning : Stricter noise regulations for commercial and military aircraft have increased interest in noise reduction techniques within the aerospace industry. To meet the requirements, new noise suppression technologies have to be developed and numerical methods need to be validated and possibly improved for the correct assessment of these technologies. LÄS MER

  3. 7. New Methods for Reducing Ground-Borne Noise in Buildings above Railway Tunnels

    Författare :Osama A. B. Hassan; KTH; []
    Nyckelord :Ground-borne noise; railway noise; in-plane waves; wave-guides; scattering; propagation constant; input mobility; elastic stratum; dual integral equations;

    Sammanfattning : The rapid expansion of major cities in the west Europeancountries has accentuated the need to exploit every potentialsite for new establishments, e.g. areas over train tunnels andnear railway tracks in general. LÄS MER

  4. 8. Multidirectional Mobilities - Advanced Measurement Techniques and Applications

    Författare :Lars H. Ivarsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; R-DOFs; substructuring; measurement techniques; rotational mobility; multidirectional mechanical mobility; hybrid coupling; coupling; moment mobility; impedance coupling; consistency;

    Sammanfattning : Today high noise-and-vibration comfort has become a quality sign of products in sectors such as the automotive industry, aircraft, components, households and manufacturing. Consequently, already in the design phase of products, tools are required to predict the final vibration and noise levels. LÄS MER

  5. 9. Instrumental and observational studies in radio astronomy : low noise amplifier design and methanol maser research

    Författare :Vincent Minier; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; circumstellar matter; HEMT; matching circuitry design; techniques: interferometric; masers; microwave; low noise amplifier; HII regions; stars: formation;

    Sammanfattning : .... LÄS MER

  7. 10. InP High Electron Mobility Transistors for Cryogenic Low-Noise and Low-Power Amplifiers

    Författare :Eunjung Cha; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; indium channel content; electrical stability.; dc power dissipation; noise temperature; scaling; low-noise amplifier LNA ; InP high-electron mobility transistor InP HEMT ; cryogenic;

    Sammanfattning : The InAlAs/InGaAs/InP high-electron mobility transistor (InP HEMT) is the preferred low-noise device in cryogenic low-noise amplifiers (LNAs) operating at 5-15 K. Such LNAs are utilized in microwave and millimeter-wave detection in radio astronomy. LÄS MER