Sökning: "impact excitation"

Visar resultat 11 - 15 av 76 avhandlingar innehållade orden impact excitation.

  1. 11. First Principles Calculations of Electron Transport and Structural Damage by Intense Irradiation

    Författare :Carlos Ortiz; Olle Eriksson; Mattias Klintenberg; Richard A. London; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Condense matter theory; electronic structure; quasiparticles; GW theory; molecular dynamics; Boltzmann transport; electron transport; impact ionization; structural damage; dielectric response; structural biology; radiation detectors; scintillators; positron emission tommography; Electronic structure; Elektronstruktur; Semiconductor physics; Halvledarfysik; Biological physics; Biologisk fysik; Critical phenomena phase transitions ; Kritiska fenomen fasövergångar ; Functional materials; Funktionella material; Materiefysik; Physics of Matter;

    Sammanfattning : First principle electronic structure theory is used to describe the effect of crystal binding on radiation detectors, electron transport properties, and structural damage induced by intense irradiation. A large database containing general electronic structure results to which data mining algorithms can be applied in the search for new functional materials, a case study is presented for scintillator detector materials. LÄS MER

  3. 12. Structural Earthquake Response Analysis

    Författare :Hamid Movaffaghi; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; finite element method; Earthquake excitation; global and local optimization; viscoelastic passive dampers; stochastic simulation; structural earthquake response analysis;

    Sammanfattning : AbstractEarthquakes are one of the most dangerous natural phenomena causing damage to buildings and other structures as well as injury and death of people. These destructive processes can never be prevented to happen, but their impact on the structures can be minimized. LÄS MER

  4. 13. Application of Automated Non-contact Resonance Testing for Low Temperature Behavior of Asphalt Concrete

    Författare :Abiy Bekele; Nils Ryden; Safwat Said; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Resonance testing; stiffness modulus; asphalt concrete; Non-contact excitation; Resonance frequency; Civil and Architectural Engineering; Byggvetenskap;

    Sammanfattning : Impact resonance testing is a well-documented non-destructive testing method and its applications on asphalt concrete have also been implemented successfully. The test is carried out manually by inducing an impact in order to excite the test specimen and taking measurements of the vibrational response. LÄS MER

  5. 14. Some Aspects of Wear and Structural Dynamics

    Författare :Jakob Knudsen; Hållfasthetslära; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vibration and acoustic engineering; Mechanical engineering; hydraulics; chaos; interfacial breakdown; stability; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik; vacuum technology; fretting wear; fretting map; vibro-impact dynamics;

    Sammanfattning : The topic of this thesis is dynamics and wear of structures. In the six appended papers different aspects of wear and dynamics of a model system are studied. The considered system consists of a long slender rod with unilateral supports, subject to harmonic and stochastic excitation. LÄS MER

  7. 15. On the Chemical Composition of Metal-Poor Stars : Impact of Stellar Granulation and Departures from Local Thermodynamic Equilibrium on the Formation of Spectral Lines

    Författare :Remo Collet; Bengt Gustafsson; Martin Asplund; Roger Cayrel; Uppsala universitet; []
    Nyckelord :Astronomy; late-type stars; stellar abundances; stellar atmospheres; spectral line formation; convection; hydrodynamics; Galactic chemical evolution; Astronomi;

    Sammanfattning : The information about the chemical compositions of stars is encoded in their spectra. Accurate determinations of these compositions are crucial for our understanding of stellar nucleosynthesis and Galactic chemical evolution. LÄS MER