Search for dissertations about: "proper motions"

Showing result 1 - 5 of 12 swedish dissertations containing the words proper motions.

  2. 1. Tycho-Gaia and beyond: Combining data for precision astrometry

    Author : Daniel Michalik; Astronomi - Genomgår omorganisation; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; proper motions; parallaxes; positions; map of the Milky Way; joint solution; Gaia; detection of exo-planets; astrometry; catalogue combination; Tycho-Gaia Astrometric Solution; Hundred Thousand Proper Motion project; Fysicumarkivet A:2015:Michalik;

    Abstract : Astrometry aims at producing a three-dimensional map of positions and motions of stars and other celestial bodies in a consistent coordinate system covering the whole sky. This is best done from space, which provides a way of scanning the entire sky by a single instrument in a thermally stable environment. READ MORE

  4. 2. Vortices in turbulent curved pipe flow-rocking, rolling and pulsating motions

    Author : Athanasia Kalpakli Vester; P. Henrik Alfredsson; Ramis Örlü; Nils Tillmark; Knud Meyer; KTH; []
    Keywords : Turbulence; curved pipes; swirling flow; pulsatile flow; time-resolved stereoscopic particle image velocimetry; hot-wire anemometry; proper orthogonal decomposition; turbocharger;

    Abstract : This thesis is motivated by the necessity to understand the flow structure of turbulent flows in bends encountered in many technical applications such as heat exchangers, nuclear reactors and internal combustion engines. Flows in bends are characterised by strong secondary motions in terms of counter-rotating vortices (Dean cells) set up by a centrifugal instability. READ MORE

  5. 3. Towards 6 Degrees of Freedom Seakeeping Simulations Using a Fully Nonlinear Potential Flow Method

    Author : Francesco Coslovich; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ship Motions; Added Resistance; Boundary Element Method; Fully Nonlinear Potential Flow; Seakeeping;

    Abstract : In recent years, the International Maritime Organization introduced a new set of rules in order to try to reduce emissions of ships by improving their efficiency. To assess the energy efficiency of a new ship, the regulations require to estimate the Energy Efficiency Design Index (EEDI), which represent the amount of Carbon Dioxide produced per mile in relation to the amount of cargo carried, and verify that it is smaller than a prescribed value. READ MORE

  6. 4. Evaluation of isovolumic myocardial motions in human subjects using tissue velocity echocardiography

    Author : Britta Lind; Karolinska Institutet; Karolinska Institutet; []
    Keywords : ;

    Abstract : Colour-coded tissue velocity imaging (TVE) with Echocardiography is an established method for evaluation of the global cardiac function and of the regional myocardial movements. The TVE-technique allows measurements of velocity and deformation variables from any discrete point in the myocardial wall during the cardiac cycle with high temporal and longitudinal spatial resolution. READ MORE

  7. 5. Structure of Zero Pressure Gradient High Reynolds Number Turbulent Boundary Layers

    Author : Murat Tutkun; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fourier decomposition.; proper orthogonal decomposition; large scale structures; Turbulent boundary layers; zero pressure gradient; wind tunnel; calibration; cross-correlations; hot-wire; two-point correlations; high Reynolds number;

    Abstract : This thesis presents part of the large research program funded by the European Commission calledWallturb: A European synergy for the assessment of wall turbulence. The main aim of this researchprogram is to create new experimental and numerical databases on the characteristics of turbulent wall-bounded flows, especially turbulent boundary layers. READ MORE