Sökning: "Lars Dahlström"

Visar resultat 1 - 5 av 12 avhandlingar innehållade orden Lars Dahlström.

  1. 1. Freezing Temperature Flows in Railway Tunnels and its Consequence on the Rock Supporting Structure, the Rock and the Reinforcing Elements

    Författare :Anna Andrén; Lars-Olof Dahlström; Erling Nordlund; Lars O Ericsson; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tunnel; frost penetration; ice formation; freeze-thaw test; frost shattering; temperature measurement; maintenance; degradation of rock and shotcrete; cold climate; Tunnel; köldinträngning; isbildning; frystester; frostsprängning; temperaturmätning; underhåll; nedbrytning av berg och sprutbetong; kallt klimat; Mining and Rock Engineering; Gruv- och berganläggningsteknik;

    Sammanfattning : Water in the surrounding rock mass flows into the tunnel via naturally occurring joints and via cracks caused by the blasting used to excavate the tunnel. The most common method in Sweden to reduce or prevent leakage problems are first and foremost the use of grouting. LÄS MER

  3. 2. Post-apartheid teacher education reform in Namibia : the struggle between common sense and good sense

    Författare :Lars Dahlström; Umeå universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; teacher education reform; hegemony; counter-hegemony; post-apartheid; Namibia; International education; Internationell pedagogik;

    Sammanfattning : This thesis is about teacher education reform. It is a narrative of attempted change in the area of teacher education in post-apartheid Namibia. The inquiry is based on critical and participatory perspectives. The analytical tools include concepts like hegemony and counter-hegemony, common sense and good sense. LÄS MER

  4. 3. Rock Mechanical Consequences of Refrigeration. A Study Based on a Pilot Scale Rock Cavern

    Författare :Lars-Olof Dahlström; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; temperature decrease; tensile strength; thermomechanical loading; compressive strength; Poisson s ratio; thermal contraction; rock caverns; rock mass deformation; Young s modulus;

    Sammanfattning : The deformation of a rock mass due to temperature decrease below freezing is very complex, since many factors are involved; thermal strain, strain due to stress change, stress re-distribution, ice formation and the temperature dependency of rock mechanical and thermo-physical properties. The objective of this study was to achieve a better understanding of the rock mass response to thermo-mechanical loading when storing low temperature products in rock caverns excavated in hard crystalline rock masses. LÄS MER

  5. 4. New Insights on Computerized Trading : Implications of Frequently Revised Trading Decisions

    Författare :Petter Dahlström; Björn Hagströmer; Lars Nordén; Andriy Shkilko; Stockholms universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Business Administration; företagsekonomi;

    Sammanfattning : Computerized trading may be viewed as an aspect of modernization of financial markets. This dissertation contains four articles that in different ways examine to what extent the modernization influences the economics of the markets. LÄS MER

  7. 5. Aspects of Tumour Targeting : Preclinical Studies on Human Malignant Cells in vitro

    Författare :Maria Dahlström Wester; Annelie Lindström; Åke Wasteson; Lars Gedda; Linköpings universitet; []
    Nyckelord :MEDICINE; MEDICIN;

    Sammanfattning : Exclusive eradication of tumour cells causing minimal damage to healthy tissue, a concept referred to as targeting, is an interesting approach to improve the outcome for patients afflicted with cancer.The general aim of this thesis was to highlighten aspects that could be of importance in developing novel treatment regimens based on specific targeting of tumour cells. LÄS MER