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Visar resultat 1 - 5 av 98 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Vissa drag i Badelundaåsens geohydrologi : (Sträckan Mälaren - Sätra brunn)

    Författare :Jan De Geer; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Undersökningen har genomförts som en hydrogeologisk, lokalregional inventering av Badelundaåsen och dess biåsar. Den speciellt inriktade kartering, som utfördes i skalan 1:20 000 omfattade själva åsen jämte dalens begränsning. LÄS MER

  3. 2. Aerodynamic Investigation of Truck-Trailer Combinations

    Författare :Helena Martini; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aerodynamics; vehicle combinations; trucks; drag reduction;

    Sammanfattning : In today’s society, increasing fuel prices and the constantly evolving emission legislation, forces the vehicle industry to develop new techniques for the propul- sion of vehicles, and optimization of existing technology. Trucks constitute a significant proportion of the transportation system, consequently it is of great importance to ensure as low an impact as possible on the environment. LÄS MER

  4. 3. Modelling and control of turbulent and transitional flows

    Författare :Pierluigi Morra; Dan S. Henningson; Ardeshir Hanifi; André V. G. Cavalieri; Shervin Bagheri; Aimee S. Morgans; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; reduced order modeling; flow control; resolvent analysis; transi- tional boundary layer; turbulent boundary layer; drag reduction; high-fidelity wall-turbulence modelling; modellreduktion; strömningskontroll; resolvent analys; laminär- turbulent omslag; turbulent gränsskikt; motståndsminskning; väggturbulens modellering; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : The dynamics of fluid motion can accurately be described by the Navier– Stokes equations. Manipulating these equations to reduce their complexity but preserving their main characteristics has always been a key research activity in the field of fluid mechanics. LÄS MER

  5. 4. Metabolic regulation of nitrogenase in Rhodospirillum rubrum : studies on DRAG and DRAT, the regulatory proteins of dinitrogenase reductase

    Författare :Agneta Norén; Gary Robert; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biochemistry; Biokemi; Biochemistry; biokemi;

    Sammanfattning : Nitrogen fixation is catalyzed by nitrogenase, in an ATP-dependent reaction where dinitrogen is reduced to ammonium. Nitrogenase is a protein complex consisting of two proteins; dinitrogenase and dinitrogenase reductase and the reaction is only carried out by prokaryotes. LÄS MER

  7. 5. Prediction of Wing Section Lift and Drag from Numerical Solutions of the Navier-Stokes Equations

    Författare :Björn Regnström; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; airfoil; incompresible flow; computational fluid dynamics; transition; numerical analysis; boundary layer stability;

    Sammanfattning : A Navier-Stokes finite difference method is developed and applied to two-dimensional, incompressible, viscous flow around wing sections at medium to high Reynolds numbers. An important feature of such flows is laminar boundary layers with spatially amplified Tollmien-Schlichting waves initiating transition to turbulence. LÄS MER