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Gopherus berlandieri
Number of Pages: 2Integrative BiologyGeological Science
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Number of Pages: 2Integrative BiologyGeological Science
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Bufo quercicus
Number of Pages: 2Integrative BiologyGeological Science
Avon Park Air Force Range project: distribution and abundance of sensitive wildlife species at Avone Park Force Range
Executive Summary. We surveyed for seven species ofsensitve wildlife (Florida gopher frogs,
gopher tortoise, eastern indigo snake, eastern diamondback rattlesnake, Florida mouse, Florida
roundtail muskrat, Sherman's fox squirrel) between October 1996 and May 1998 at Avon Park
Air Force Range (APR). The presence of 87 other species ofamphibians, reptiles, and mammals
also were detected. Selected species ofbirds were noted, particularly if they were found dead on
APR roads. We recorded nine new county records ofamphibians and reptiles from Polk and
Highlands counties, based on range maps presented in Ashton and Ashton (1981, 1985, 1988).
We discuss a biogeographic model based on the vertebrates recorded from APR, the Lake Wales
Ridge, and the low dune region along SR 64 to explain some of the distributional anomalies
associated with the Bombing Range Ridge and vicinity. (199 page document
Aggregating causal judgements
Decision making typically requires judgements about causal relations. We need to know both the causal effects of our actions and the causal relevance of various environmental factors. Judgements about the nature and strength of causal relations often differ, even among experts. How to handle such diversity is the topic of this paper. First we consider the possibility of aggregating causal judgements via the aggregation of probabilistic ones. The broadly negative outcome of this investigation leads us to look at aggregating causal judgements independently of probabilistic ones. We do so by transcribing causal claims into the judgement aggregation framework and applying some recent results in this field. Finally we look at the implications for probability aggregation when it is constrained by prior aggregation of causal judgements.mathematical economics;
Dynamics and termination cost of spatially coupled mean-field models
This work is motivated by recent progress in information theory and signal
processing where the so-called `spatially coupled' design of systems leads to
considerably better performance. We address relevant open questions about
spatially coupled systems through the study of a simple Ising model. In
particular, we consider a chain of Curie-Weiss models that are coupled by
interactions up to a certain range. Indeed, it is well known that the pure
(uncoupled) Curie-Weiss model undergoes a first order phase transition driven
by the magnetic field, and furthermore, in the spinodal region such systems are
unable to reach equilibrium in sub-exponential time if initialized in the
metastable state. By contrast, the spatially coupled system is, instead, able
to reach the equilibrium even when initialized to the metastable state. The
equilibrium phase propagates along the chain in the form of a travelling wave.
Here we study the speed of the wave-front and the so-called `termination
cost'--- \textit{i.e.}, the conditions necessary for the propagation to occur.
We reach several interesting conclusions about optimization of the speed and
the cost.Comment: 12 pages, 11 figure
Master of Science
thesisThe purpose of this research is to present an analysis of the leakage potential of sequestering CO2 in a reservoir that exhibits faulting, but may or may not have a fault penetrating the reservoir seal. A hypothesis is that CO2 injected into the reservoir will leak through a fault system. The questions addressed by this thesis are: (1) Under what conditions will CO2 leak through a fault and how much will leak under different conditions? (2) How much time is required for CO2 to migrate through an unbroken seal formation? (3) Under what conditions will permeable reservoirs above the target reservoir intercept or "catch" CO2 leaking through a fault? (4) Is injecting into two reservoirs preferable to injection into one? Questions (1) and (4) were addressed with site-specific models, whereas questions (2) and (3) were addressed with generic hydrogeologic models. Simulations using multi- and single-continuum models were used to analyze the leakage potential from a geological storage reservoir. Fault conduits and geologic formation porosities and permeabilities were used as constraining parameters in a sensitivity analysis. Model results highlighted that a fault above (but not penetrating) the injection reservoir increases the seepage velocity through a seal, causing a greater risk of CO2 leakage due to the increase of pressure during injection (question (1) above). Simple 1-D seal models illustrate that un-fractured, low-permeability formations are very effective at trapping CO2 for decades and longer, depending on permeability (question (2) above). Additional simulation results illustrated that with a penetrating fault through a seal facilitating direct CO2 leakage, a ratio of fault to medium permeability of two orders of magnitude difference or greater will, in many if not most cases, recapture the CO2 in shallower formations, reducing or eliminating leakage to the surface (question (3) above). Finally, this analysis suggests that a single-reservoir injection (question (4) above) is best since a stacked reservoir would decrease the overall risk of CO2 leakage during and after injection, highlighted by results of the question (3) analysis
Evening Star : From Tannhauser
https://digitalcommons.library.umaine.edu/mmb-vp/5634/thumbnail.jp
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