Sökning: "wave period distribution"

Visar resultat 1 - 5 av 24 avhandlingar innehållade orden wave period distribution.

1. 1. Numerical Modelling and Statistical Analysis of Ocean Wave Energy Converters and Wave Climates

   Författare :Wei Li; Isberg Jan; Jens Peter Kofoed; Uppsala universitet; []
   Nyckelord :Wave power; Wave energy converter; Gravity-based foundation; Power absorption; Wave spectrum; Linear generator; Frequency domain; Wave climate; Ocean wave modelling; Mixed-distribution model; Bivariate distribution; Archimedean copula;

   Sammanfattning : Ocean wave energy is considered to be one of the important potential renewable energy resources for sustainable development. Various wave energy converter technologies have been proposed to harvest the energy from ocean waves. This thesis is based on the linear generator wave energy converter developed at Uppsala University. LÄS MER

3. 2. Fatigue Assessment and Extreme Response Prediction of Ship Structures

   Författare :Wengang Mao; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fatigue assessment; extreme response; rainflow; narrow-band approximation; Laplace Moving Average model; transformed Gaussian; zero up-crossing response frequency; significant wave height; safety index; upcrossing spectrum; long term cumulative distribution function; ship routing.; transformed Gaussian;

   Sammanfattning : In this thesis, a simplified narrow-band approximation model is proposed to estimate fatigue damage of ship structures, and an efficient method for extreme response predictions is also developed using upcrossing spectrums of ship responses. The proposed fatigue model includes two main parameters, significant stress range hs and zero upcrossing frequency fz. LÄS MER

4. 3. Nematic Liquid Crystal Spatial Light Modulators for Laser Beam Steering

   Författare :Emil Hällstig; Mikael Lindgren; Lars Sjöqvist; William Crossland; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; spatial light modulator; liquid crystal; beam steering; tracking; phase modulation; fringing field; director distribution; finite-difference time-domain; polarization; temporal properties; Fysik; Physics; Fysik;

   Sammanfattning : Laser beam control is important in many applications. Phase modulating spatial light modulators (SLMs) can be used to electronically alter the phase distribution of an optical wave-front and thus change the direction and shape of a laser beam. LÄS MER

5. 4. Land Reform, Trust and Natural Resource Management in Africa

   Författare :Precious Zikhali; Göteborgs universitet; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Africa; Agricultural productivity; Bioeconomic model; Dynamic analysis; Land reform; Ethnicity; Ethnic nepotism; Investments; Mopane worm; Restrictive harvest period policy; Tenure security; Trust; Zimbabwe.;

   Sammanfattning : Four self-contained papers constitute this thesis. Paper I investigates what impact Zimbabwe’s Fast Track Land Reform Programme, launched in 2000 as part of an ongoing land reform and resettlement programme aimed at addressing a racially skewed land distribution, has had on its beneficiaries’ perceptions of land tenure security and subsequent decisions to invest in soil conservation. LÄS MER

7. 5. Seismicity and earthquake source mechanism study in the East African rift

   Författare :Atalay Ayele; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; Geovetenskap; Earth sciences; Geovetenskap; Geofysik med inriktning mot seismologi; Geophysics with specialization in Seismology;

   Sammanfattning : A new earthquake catalogue of the Horn of Africa has been compiled for the period from 1960 to 1993. The threshold magnitude of this catalogue is found to be 4.5 (mb). Spatial and temporal variation of seismic energy release and b-value are investigated for this catalogue. LÄS MER