Search for dissertations about: "natural convection"

Showing result 21 - 25 of 138 swedish dissertations containing the words natural convection.

  2. 21. Lake Fluxes of Methane and Carbon Dioxide

    Author : Eva Podgrajsek; Erik Sahlée; Dennis Baldocchi; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; air-lake gas exchange; carbon dioxide; eddy covariance; floating chambers; methane; waterside convection; Meteorology; Meteorologi;

    Abstract : Methane (CH4) and carbon dioxide (CO2) are two important greenhouse gases. Recent studies have shown that lakes, although they cover a small area of the globe, can be very important natural sources of atmospheric CH4 and CO2. READ MORE

  4. 22. On the representation of precipitation in high-resolution regional climate models

    Author : Petter Lind; Erik Kjellström; Michael Tjernström; Jan Erik Haugen; Anna Rutgersson; Abdel Hannachi; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Regional climate modeling; high-resolution; convection parameterization; precipitation; extremes; statistical analysis; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography; meteorologi; Meteorology;

    Abstract : Weather and climate models applied with sufficiently fine mesh grids to enable a large part of atmospheric deep convection to be explicitly resolved have shown a significantly improved representation of local, short-duration and intense precipitation events compared to coarser scale models. In this thesis, two studies are presented aimed at exploring the dependence of horizontal resolution and of parameterization of convection on the simulation of precipitation. READ MORE

  5. 23. Convection-diffusion equation in unbounded cylinder and related homogenization problems

    Author : Iryna Pankratova; Luleå tekniska universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Mathematics; Matematik;

    Abstract : The thesis consists of two closely related papers (A and B). Paper A is concerned with the study of the behaviour at infinity of solutions to second order elliptic equation with first order terms stated in a half-cylinder. READ MORE

  6. 24. Carbon Nanotube Transistors: Nanotube Growth, Contact Properties and Novel Devices

    Author : Johannes Svensson; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Carbon nanotube; chemical vapour deposition; Field effect transistor; Marangoni convection; Schottky barrier;

    Abstract : Carbon nanotubes (CNTs) are envisioned to be used as the basic building blocks in future electronics due to their excellent electronic properties such as high mobility, compatibility with high-k dielectrics and small diameters resulting in advantageous electrostatics. This thesis is divided into three separate topics related to increasing the fabrication yield and performance of CNT field effect transistors (CNTFETs). READ MORE

  7. 25. Studies on the Gamma Radiation Environment in Sweden with Special Reference to 137Cs

    Author : Sara Almgren; Göteborgs universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; gamma radiation; caesium; 137Cs; deposition; migration; precipitation; in situ; CDE; NWF; Chernobyl; soil sampling; field measurements; dose measurements; dose rate; TLD; natural radiation; Kriging;

    Abstract : Gamma radiation in the environment today mainly originates from naturally occurring radionuclides, but anthropogenic radionuclides, such as 137Cs, contribute in some areas. In order to assess population exposure in case of fallout from nuclear weapons (NWF) or accidents, knowledge and monitoring of external gamma radiation and radionuclide concentrations in the environment is important. READ MORE