Search for dissertations about: "threshold current"

Showing result 1 - 5 of 169 swedish dissertations containing the words threshold current.

  2. 1. Linear, Non-Linear, and Synchronizing Spin Wave Modes in Spin Hall Nano-Oscillators

    Author : Hamid Mazraati; Johan Åkerman; Dario Arena; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; spin Hall effect; spin Hall nano-oscillators; threshold current; microwave; spin wave; synchronization; Fysik; Physics;

    Abstract : Spin Hall nano-oscillators (SHNOs) are nanoscale spintronic devices that generate microwave signals with highly tunable frequency. This thesis focuses on improving the signal quality of nanoconstriction-based SHNOs and also on developing a better understanding of their magnetization dynamics. READ MORE

  4. 2. Dilute Nitride Lasers and Spectrally Engineered Semiconductor Laser Resonators

    Author : Göran Adolfsson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; single mode laser; transfer matrix method; threshold current; InGaAs; GaAs; multiple quantum wells; dilute nitrides; two-color laser; GaInNAs; Semiconductor lasers; molecular beam epitaxy; characteristic temperature; temperature dependence; ambipolar diusion; Fabry-Perot resonator; spectral engineering;

    Abstract : The first part of this thesis deals with long wavelength (1.2-1.3 um) InGaAs(N)multiple quantum-well (QW) lasers grown on GaAs, with the aim of understandingand improving their threshold and temperature characteristics. The epitaxialmaterial is grown by molecular beam epitaxy (MBE). READ MORE

  5. 3. Development of traffic conflicts technique for different environments: A comparative study of pedestrian conflicts in Sweden and Jordan

    Author : Lina Shbeeb; Trafik och väg; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; perception of conflicts.; non-signalised junctions; signalised junctions; accident prediction; accident to conflict conversion factors; TA-speed graphs; conflict speed; time to accidents; conflict sub-grouping; severity index; threshold; relevant road-user; pedestrian conflict; Traffic safety; traffic conflict technique; Technological sciences; Teknik; Social sciences; Samhällsvetenskaper;

    Abstract : This study is aimed at improving the current Swedish Traffic conflicts Technique [TCT] in relation to vehicle-pedestrian conflicts. The present definition of conflict severity appears to produce less severe conflicts than they might be, particularly if the relevant road user (RRU) is the pedestrian. READ MORE

  6. 4. Improvement and Assessment of Two-Dimensional Resistivity Models Derived from Radiomagnetotelluric and Direct-Current Resistivity Data

    Author : Thomas Kalscheuer; Laust B. Pedersen; Christopher Juhlin; Roland Roberts; Heinrich Brasse; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Electromagnetic geophysics; radiomagnetotellurics; direct-current resistivity; displacement currents; dielectric effect; non-linearity; inversion; regularization; two-dimensional model; model variance; model resolution; data resolution; Geophysics; Geofysik;

    Abstract : Two-dimensional (2-D) models of electrical resistivity are improved by jointly inverting radiomagnetotelluric (RMT) and direct-current resistivity (DCR) data or by allowing for displacement currents in the inversion of RMT data collected on highly resistive bedrock. Uniqueness and stability of the 2-D models are assessed with a model variance and resolution analysis that allows for the non-linearity of the inverse problem. READ MORE

  7. 5. Direct Extraction of MOS Transistor Current Model Parameters

    Author : Peter R. Karlsson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : This thesis presents a study of MOS transistor model parameter extraction. The objective of this study was to develop an efficient, accurate, robust extraction strategy which determines physically reasonable parameter values. The direct parameter extraction approach was chosen to meet these requirements. READ MORE