Search for dissertations about: "natural frequency bar"

Showing result 1 - 5 of 10 swedish dissertations containing the words natural frequency bar.

  2. 1. Conservation of semi-natural grasslands : Effects of different management methods on biodiversity

    Author : Malin Tälle; Lars Westerberg; Per Milberg; Uno Wennergren; Hans Henrik Bruun; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : Species-rich semi-natural grassland are valuable habitats in the agricultural landscape as they may contain a high diversity of both plant and animal species, as well as provide essential ecosystem services like pollination. To keep these habitats open and to maintain the biodiversity in them, management like grazing or mowing is necessary. READ MORE

  4. 2. Numerical Studies of Extragalactic Objects. Analysis of mmVLBI Observations and Simulations of Barred Spiral Galaxies

    Author : Mikael Lerner; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; quasars; galactic dynamics; barred galaxies; N-body simulations; VLBI; model fitting;

    Abstract : Numerical studies related to high-frequency VLBI observations of quasars and dynamics of barred spiral galaxies have been performed. Data from a global 100 GHz VLBI experiment has been reduced and a radio image of the quasar 3C 446 with the highest resolution achieved to date has been produced. READ MORE

  5. 3. Frazil ice at water intakes

    Author : Annika Andersson; Luleå tekniska universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Applied Geology; Tillämpad geologi;

    Abstract : To provide a better understanding of how frazil ice deposits on trash racks at water intakes, the phenomenon was video recorded at two hydropower plants and in a refrigerated laboratory flume. Initial accretion of frazil ice around a single bar and the motion of particles in the vicinity of an obstacle was simulated through numerical modelling and studied using plastic particles in a laboratory flume. READ MORE

  6. 4. Motion Vision Processing in Fly Lobula Plate Tangential Cells

    Author : Yu-Jen Lee; Karin Nordström; Holger Kraap; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; hoverflies; EMD; higher order motion; octopamine; cSIFE; figure-ground discrimination; motion vision; lobula plate tangential cells;

    Abstract : Flies are highly visually guided animals. In this thesis, I have used hoverflies as a model for studying motion vision. Flies process motion vision in three visual ganglia: the lamina, the medulla, and the lobula complex. In the posterior part of lobula complex, there are around 60 lobula plate tangential cells (LPTCs). READ MORE

  7. 5. Dynamics of the interstellar matter in galaxies : isolated barred spiral galaxies : cloud formation processes

    Author : Kristen Helmuth; John Beckman; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; Astronomi; Astronomy; astronomi;

    Abstract : The dynamical components of six isolated barred spiral (SB) galaxies are investigated. No evidence is found supporting the hypothesis of a low amount of dark matter being characteristic of SB galaxies. The presence of companion galaxies is found to correlate with an increased statistical spread in the neutral hydrogen (HI) extent. READ MORE