Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 45 for “"Evolution models"”.
-
Hiding in plain sight: accounting for rate heterogeneity in trait evolution models
… matched by an explosion of possible phylogenetic models. In large part, the efforts to increase the realism of phylogenetic comparative methods has been successful as evidenced by their widespread use. To this extensive literature, my contributions are modest. I have focused my dissertation work …
-
An investigation of fit measures for longitudinal network and attribute co-evolution models
… Fit measures have been developed for actor-based models of network structural evolution (Schweinberger, 2007; Snijders, 1996). Snijders et al. (2006) extended the actor-based structural evolution model to an actor-based co-evolutionary model that includes actor attributes. Despite recent …
-
Overcoming unrealistic behavior of landscape evolution models attributed to the stream power incision model: Scale invariance and ultra-sensitivity to initial conditions
Landscape evolution models (LEMs) have been used as tools for geomorphologist to explain and understand mountain formation and landform development. Initially these models were conceptual ideas of how geomorphic processes create the landscapes we see today. Now, we predominantly use numerical …
-
Forward jet production in neutral current deep inelastic scattering with ZEUS at HERA
… events are selected to probe different parton evolution models. The measured cross sections depending on Bjoerken-x and transverse energy are based on the luminosity of 76 pb-1. For the running period of 1998-2000 the calorimetric acceptance was extended in pseudo-rapidity using the Forward …
-
The evolution of isotoipc abundances from high-redshift to the local universe
… chemical elements. Using our Galactic chemical evolution code CEtool, we have examined the evolution of these isotopes within the framework of a Milky Way-like system. We have three aims in this thesis: first, to test the claim that novae are required, in order to explain the carbon isotope …
-
Effects of differential rainfall on the dynamics of landscape evolution
The field of landscape evolution modeling focuses on the evolution of the structure of landscapes over geologic time. The elevations of rivers, valleys, hills, and mountains make up the structure of the landscape. Generally, these elevations change due rock uplift as well as incision. Rivers are …
-
Lithologic Controls on Bedrock Channel Morphology in the Buffalo River Basin
… phenomenon in geomorphology. Current landscape evolution models assume an equilibrium state between rock uplift rates and erosion rates. However, analysis of chi gradients of bedrock channels across several lithologies in the Buffalo River Basin reveals disequilibrium in the basin controlled by …
-
Rotation and magnetism in massive stars
Rotation has a number of important effects on the evolution of stars. Apart from structural changes because of the centrifugal force, turbulent mixing and meridional circulation can dramatically affect a star's chemical evolution. This leads to changes in the surface temperature and luminosity as …
-
Melt-freeze crust formation and evolution in the Columbia Mountains
… many slab avalanches. Recent work with snowpack models has shown the need for field based research on the formation and evolution of melt-freeze crusts. This project uses historical weather and snowpack data to determine the metrological conditions during crust formation and the resulting crust …
-
Global in time existence of Sobolev solutions to semi-linear damped sigma-evolution equations in L^q scales
… data Sobolev solutions to semi-linear damped σ-evolution equations from suitable function spaces basing on L^q spaces by mixing additional L^m regularity for the data on the basis of L^q-L^q estimates for solutions, with q∈(1,∞) and m∈[1,q), to the corresponding linear models. To establish …
-
Polyploidy inference across time scales in the charismatic carnivorous plant genus Drosera L. (Droseraceae, Caryophyllales)
… to develop Drosera as a system for chromosome evolution. This was achieved by using chromosome evolution models to test different rates of chromosome evolution between different subgenera in Chapter 1. In Chapter 2, I inferred the parental lineages of Drosera anglica, a neopolyploid, and in …
-
Does the theory of parameterized conveciton apply to layered mantle convection?
There are numerous models for convection of the Earth's mantle, the end cases of which are whole-mantle convection and layered convection. Heat flow is an important consideration in the evalution of these models. Simple thermal evolution models based on boundary layer theory have in the past been …
-
Geomechanical and tectonic investigations into the geologic history of Mars at local, regional, and global scales
… of these values to those predicted by thermal evolution models for Mars shows that thermal evolution models significantly overpredict the amount of strain and associated planetary radius decrease for both time periods. Results of this study also support the hypothesis that a "pulse" of enhanced …
-
The sedimentary record of seafloor uplift
… This thesis investigates the different origins, evolution, and impacts of various uplifting mechanisms on deep-water sedimentary records based on the interpretation of geomorphological and geophysical data. Here, sedimentary and morphological proxies are linked to different uplift …
-
The galactic evolution ofs-process elements via asymptotic giant branch stars
… the current confusion. Results from stellar evolution models are brought together in order to establish trends of certain parameters as functions of one or two other parameters. Using these parameterizations, we have determined the s-process abundances created by these stars for different …
-
K-Star rapid rotators and the detection of relatively young multiple K-Star systems
… 14,440 K star targets is consistent with spin evolution models that presume an initial contraction phase followed by spin down due to magnetic braking where typical K stars would be expected to spend up to a few hundred million years before slowing down to a rotation period of more than 2 days.
-
Coastal evolution on Earth and Titan
… of its coasts using a combination of landscape evolution models and measurements of shoreline shape. Results show that the coastlines of Titan’s seas are consistent with those of both modelled and Earth lakes with flooded river valleys that have been subsequently eroded by waves, particularly …
-
ASSESSING THE ROLE OF EXTERNAL PHOTOEVAPORATION OF PROTOPLANETARY DISCS IN NEARBY STAR-FORMING REGIONS
… physical processes driving protoplanetary disc evolution and the connection to the star-forming environment is essential to understanding planet formation and diversity. Most stars (and their discs) in the Galaxy form in massive clusters where the intense UV radiation emitted by OBA-type stars …
-
Characterisation Of The Blazhko Effect In RR Lyrae Stars Using SuperWASP Data
… are still unexplained by stellar structure and evolution models. The stellar pulsation mechanism and modulation are introduced before comparing the WASP project to other wide-field surveys. The aim of this research is to identify correlations between the basic pulsation and Blazhko effect …
Page 1 of 3