Sökning: "thermal resistance"

Visar resultat 36 - 40 av 363 avhandlingar innehållade orden thermal resistance.

  1. 36. Engineering Ceramics for Tribological Systems. Manufacture, Properties and Testing

    Författare :Lars Kahlman; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; thermal wear; ceramic composite; face seal; engineering ceramic; erosion; hybrid bearing; thermal spalling; lubrication; tribology; abrasive waterjet; abrasive wear;

    Sammanfattning : A broad range of commercial and experimental grades of ceramics and ceramic composites was tested in various model tests and simplified component tests. The tests were done to establish important microstructural features, friction and wear mechanisms. LÄS MER

  2. 37. Extended Computational Module for Tractive Effort at Rolling and Spinning Point Contacts

    Författare :Mikael Törmänen; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spin; thermal effects; Hertzian contact; continuously variable transmission; rolling resistance; speed pole; traction drive; multi-body system; efficient numerical procedure;

    Sammanfattning : One category of mechanical systems that contains power-transferring point contacts is traction drive variators. These variators can be used in different concepts for Continuously Variable Transmissions (CVTs) and in vehicle applications, in order to achieve optimum engine operating conditions leading to improved driveability, reduced fuel consumption and an increase in overall vehicle performance. LÄS MER

  3. 38. Soft Intelligence : Liquids Matter in Compliant Microsystems

    Författare :Seung Hee Jeong; Zhigang Wu; Zhi-Bin Zhang; Michael D. Dickey; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Liquid; Elastomer; Cross-linking; Liquid alloy; PDMS; Adaptability; Compliance; Interface; Patterning; Printing; Surface energy; Wetting; Composite; Modulus; Stretchability; Viscoelasticity; Thermal conductivity; Contact resistance; Adhesion; Packaging; Integration; Microsystems; Microfluidics; Strain sensor; Thermoelectrics; Inductive coupling; Wireless communication; Stretchable electron-ics; Epidermal electronics; Skin electronics; Soft robotics; Wearable electronics; Teknisk fysik med inriktning mot mikrosystemteknik; Engineering Science with specialization in Microsystems Technology; Engineering Science with specialization in Materials Science; Teknisk fysik med inriktning mot materialvetenskap;

    Sammanfattning : Soft matter, here, liquids and polymers, have adaptability to a surrounding geometry. They intrinsically have advantageous characteristics from a mechanical perspective, such as flowing and wetting on surrounding surfaces, giving compliant, conformal and deformable behavior. LÄS MER

  4. 39. Characterization of Microwave Transistors for Robust Receivers and High Efficiency Transmitters

    Författare :Mattias Thorsell; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; noise modeling; access resistance; self-heating; AlGaN GaN HEMT; thermal characterization; active load-pull; load modulation;

    Sammanfattning : The next generation of integrated transceiver front-ends needs both robustlow noise amplifiers and high power amplifiers on a single-chip. The AluminiumGallium Nitride / Gallium Nitride (AlGaN/GaN) High Electron MobilityTransistors (HEMT) is a suitable semiconductor technology for this purposedue to its high breakdown voltage and high electron mobility. LÄS MER

  5. 40. Microwave power device characterization

    Författare :Kristoffer Andersson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; statistical estimation; self-heating; Silicon Carbide; Gallium Nitride; mixer; thermal resistance; wide bandgap; microwave; error-correction; small-signalmodel;

    Sammanfattning : The first part of the thesis covers work done on device characterizationmethods. A statistical method for estimating small-signal model parametersin FET-models was proposed. A maximum likelihood estimator wasderived and the new method was compared to a standard direct extractiontechnique. LÄS MER