Sökning: "torsional strain"

Visar resultat 1 - 5 av 11 avhandlingar innehållade orden torsional strain.

  1. 1. Computer-Assisted Organic Synthesis. Addition to Carbonyl Carbons and Aromatic Substitution

    Författare :Ingvar Lagerstedt; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; CAOS; torsional strain; selectivity; aromatic substitution reaction;

    Sammanfattning : This thesis concerns the computer-assisted modelling of additions to ketones and aromatic substitution, and how this modelling can be used within an existing program for synthesis planning. I include a review of existing computer-assisted organic synthesis (CAOS) programs, and discuss how some of these programs deal with knowledge representation. LÄS MER

  3. 2. Bridge Monitoring to Allow for Reliable Dynamic FE Modelling : A Case Study of the New Årsta Railway Bridge

    Författare :Johan Wiberg; Håkan Sundquist; Raid Karoumi; Björn Paulsson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bridge monitoring; FE modelling; signal analysis; torsion; warping; modulus of elasticity; natural frequency; damping; finite differences; Civil engineering and architecture; Samhällsbyggnadsteknik och arkitektur;

    Sammanfattning : Today’s bridge design work in many cases demands a trustworthy dynamic analysis instead of using the traditional dynamic amplification factors. In this thesis a reliable 3D Bernoulli-Euler beam finite element model of the New Årsta Railway Bridge was prepared for thorough dynamic analysis using in situ bridge monitoring for correlation. LÄS MER

  4. 3. Invasive and Non-Invasive Quantification of Cardiac Kinematics

    Författare :Katarina Kindberg; Matts Karlsson; Bjørn Skallerud; Linköpings universitet; []
    Nyckelord :TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : The ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. Myocardial motion can be measured by means of several different types of data acquisition. LÄS MER

  5. 4. Energy-momentum conserving time-stepping algorithms for nonlinear dynamics of planar and spatial Euler-Bernoulli/Timoshenko beams

    Författare :Sophy Chhang; Jean-Marc Battini; Mohammed Hjiaj; Reijo Kouhia; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nonlinear Dynamics; Energy-momentum conserving scheme; 2D co-rotational beam; Geometrically exact 3D Euler-Bernoulli beam; impact; Byggvetenskap; Civil and Architectural Engineering;

    Sammanfattning : Large deformations of flexible beams can be described using either the co-rotational approach or the total Lagrangian formalism. The co-rotational method is an attractive approach to derive highly nonlinear beam elements because it combines accuracy with numerical efficiency. LÄS MER

  7. 5. Modeling and experimental characterization of large biaxial strains and induced anisotropy in pearlitic rail steel

    Författare :Knut Andreas Meyer; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Pearlitic steel; yield criteria; distortional hardening; axial-torsion; kinematic hardening; biaxial loading; hyperelasto-plasticity;

    Sammanfattning : Large shear strains accumulate in the near-surface region under the running band of railway rails. In this region, rolling contact fatigue cracks often initiate, causing major problems for the railway industry. LÄS MER