Search for dissertations about: "instabilitet"

Showing result 21 - 25 of 51 swedish dissertations containing the word instabilitet.

  2. 21. Chemical Structure and Physical Properties of Organic-Inorganic Metal Halide Materials for Solid State Solar Cells

    Author : Majid Safdari; James M. Gardner; Timothy Kelly; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Perovskite; Solar cells; Organic-inorganic lead halide; Dimensionality; Bandgap; X-ray diffraction; X-ray spectroscopy.; Kemi; Chemistry;

    Abstract : AbstractMethylammonium lead (II) iodide has recently attracted considerable interest which may lead to substantial developments of efficient and inexpensive industrial photovoltaics. The application of this material as a light-absorbing layer in solid-state solar cells leads to impressive efficiency of over 22% in laboratory devices. READ MORE

  4. 22. Turbulent flows over permissive boundaries and porous walls

    Author : Seyed Morteza Habibi Khorasani; Shervin Bagheri; Geert Brethouwer; Alfredo Soldati; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct numerical simulations; wall-bounded turbulence; flow control; porous walls; heat transfer; Direkta numeriska simuleringar; väggbunden turbulens; flödeskontroll; porösa väggar; värmeöverföring; Teknisk mekanik; Engineering Mechanics;

    Abstract : This thesis investigates how in wall-bounded turbulent flows changes to the wall can induce changes in the flow. To this end, we investigate the use of wall boundary conditions meant to mimic the effect of textured surfaces. READ MORE

  5. 23. Scalable Optimization Methods for Machine Learning : Acceleration, Adaptivity and Structured Non-Convexity

    Author : Vien Van Mai; Mikael Johansson; John Duchi; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Large-scale optimization; Anderson acceleration; first-order methods; stochastic optimization; momentum; gradient clipping; Electrical Engineering; Elektro- och systemteknik;

    Abstract : This thesis aims at developing efficient optimization algorithms for solving large-scale machine learning problems. To cope with the increasing scale and complexity of such models, we focus on first-order and stochastic methods in which updates are carried out using only (noisy) information about function values and (sub)gradients. READ MORE

  6. 24. Patch loading resistance of plated girders : ultimate and serviceability limit state

    Author : Jonas Gozzi; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Steel Structures; Stålbyggnad;

    Abstract : Patch loading or partial edge loading of steel girder webs is a load case where a concentrated force is introduced perpendicular to the flange of a girder. This usually induces a local failure of the girder web in the vicinity of the loaded flange. READ MORE

  7. 25. Metabolic analysis of shikimic acid producing Escherichia coli

    Author : Louise Johansson; Avdelningen för kemiteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Kemiteknik och kemisk teknologi; Biokemi; metabolism; Chemical technology and engineering; transcriptome analysis; phosphorus-limitation; carbon-limitation; fed-batch; chemostat; batch; fermentation technology; Escherichia coli; shikimic acid; Biotechnology; Bioteknik; Metabolism; Biochemistry; principal component analysis; 2D-fluorescence spectrophotometry; metabolic flux analysis; carbon-rich;

    Abstract : Shikimic acid production using recombinant E.coli has been developed during the past 15 years due to the increased demand of this product, primarily as a starting material for the anti-influensa medicine Tamiflu?. A detailed metabolic analysis of a shikimic acid producing E. READ MORE