Sökning: "CHA"

Visar resultat 1 - 5 av 34 avhandlingar innehållade ordet CHA.

  1. 1. Airborne Particles in Railway Tunnels

    Författare :Yingying Cha; Ulf Olofsson; Roy Harrison; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : .... LÄS MER

  3. 2. InP High Electron Mobility Transistor Design for Cryogenic Low Noise Amplifiers

    Författare :Eunjung Cha; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cryogenic; stability; noise temperature; InP HEMT; LNA; MMIC;

    Sammanfattning : The InGaAs/InAlAs/InP high electron mobility transistor (InP HEMT) is the superior technology for the most demanding low-noise and high-speed microwave and millimeter-wave applications, in particular in radio astronomy and deep-space communication. InP HEMT has enabled cryogenic low noise amplifier (LNA) designs with noise temperatures about ten times the quantum noise limit from sub  GHz up to 120 GHz. LÄS MER

  4. 3. 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

  5. 4. Reappraisal of market efficiency tests arising from nonlinear dependence, fractals, and dynamical systems theory

    Författare :Gun-Ho Cha; Handelshögskolan i Stockholm; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES;

    Sammanfattning : The efficient market hypothesis (EMH) has long been perceived as the cornerstone of modern finance theory. However, the EMH has also recently been dismissed as "the most remarkable error in the history of economic theory" (Wall Street Journal, Oct. 23. 1987). LÄS MER

  7. 5. Dynamic Performance and Design Aspects of Compliant Fluid Film Bearings

    Författare :Matthew Cha; Sergei Glavatskih; Kyung-Woong Kim; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Compliant bearing; dynamic performance; design aspects; Machine Design; Maskinkonstruktion;

    Sammanfattning : Due to government regulations together with health and safety reasons, there are increasing demands on reducing hazardous polluting chemicals from fossil fuel power plants. Therefore, more efforts are imposed on using renewable resources such as water, wind, solar and tide to produce clean/green electricity. LÄS MER