Sökning: "three-dimensional model"

Visar resultat 36 - 40 av 604 avhandlingar innehållade orden three-dimensional model.

1. 36. Calibration and Reduction of Large-Scale Dynamic Models - Application to Wind Turbine Blades

   Författare :Majid Khorsand Vakilzadeh; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; maximum likelihood estimator; model reduction; finite element model calibration; Bayesian model calibration; Verification and validation; wind turbine blade; logarithmic least square estimator; large-scale dynamics model; SWPTC;

   Sammanfattning : This thesis investigates the validity of structural dynamics models of wind turbine blades. An outlook on methods for model calibration to make models valid for their intended use is presented in the thesis. The intention is to make the models valid for robust predictions. The model validity is here assessed to be of hierarchical dual level. LÄS MER

3. 37. Modelling and Simulation of Train-Track Interaction including Wear Prediction

   Författare :Clas Andersson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; full-scale measurements; rail corrugation; substructuring; wheel-rail contact; multibody dynamics; dynamic train-track interaction; three-dimensional motion;

   Sammanfattning : Many problems in railway traffic arise as a result of the dynamic interaction between rolling trains and tracks. The problems include both instantaneous effects due to induced vibrations of track and vehicle, and more long-term processes of a detrimental nature. LÄS MER

4. 38. Spectral-element simulations of turbulent wall-bounded flows including transition and separation

   Författare :Johan Malm; Dan Henningson; Philipp Schlatter; Suad Jakirlic; KTH; []
   Nyckelord :spectral-element method; direct numerical simulation DNS ; large-eddy simulation LES ; turbulence; transition; over-integration; three-dimensional separation; massively parallel simulations; proper orthogonal decomposition POD ; Koopman modes; vorticity stretching; coherence; SRA - E-vetenskap SeRC ; SRA - E-Science SeRC ;

   Sammanfattning : The spectral-element method (SEM) is used to study wall-bounded turbulent flowsin moderately complex geometries. The first part of the thesis is devoted to simulations of canonical flow cases, such as temporal K-type transitionand turbulent channel flow, to investigate general resolution requirements and computational efficiency of the numerical code nek5000. LÄS MER

5. 39. Ultrasound prediction of large fetuses. Epidemiological and clinical investigations

   Författare :Gun Lindell; Lund Obstetrik och gynekologi; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Two-dimensional ultrasound; three-dimensional ultrasound; fetus; intrauterine growth; maternal characteristic; large-for-gestational age; antenatal calculation; Bayesian theorem; fetal weight; estimation; post-term fetus; fetal macrosomia;

   Sammanfattning : The proportions of newborns with a birth weight (BW) >4,000 g and of macrosomic newborns (BW >4,500 g) have increased during the last two decades, parallel with an increasing maternal pre-pregnancy body mass index (BMI) and age at the time for pregnancy. Delivery of a large fetus, especially >4,500 g might cause perinatal complications for both the mother and her child. LÄS MER

7. 40. Making Maps and Keeping Logs : Quantum Gravity from Classical Viewpoints

   Författare :Niklas Johansson; Ulf Danielsson; Jan de Boer; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; String theory; black holes in string theory; Calabi-Yau geometry; flux compactifications; three-dimensional gravity; Mathematical physics; Matematisk fysik; Theoretical Physics; teoretisk fysik;

   Sammanfattning : This thesis explores three different aspects of quantum gravity. First we study D3-brane black holes in Calabi-Yau compactifications of type IIB string theory. Using the OSV conjecture and a relation between topological strings and matrix models we show that some black holes have a matrix model description. LÄS MER