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BLANDING’S TURTLE OCCUPANCY AND ABUNDANCE IN SOUTHERN MICHIGAN AND OHIODaniel James Earl (13943547) 13 October 2022 (has links)
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<p>Blanding’s Turtle populations face direct threats to their survival. To help protect populations, habitats that can best support Blanding’s Turtle populations need to be identified across their range. Blanding’s Turtles have been a difficult to detect species and may be present at a site even if not detected during targeted surveys. Additionally, Blanding’s Turtles may be present at a site but may have little to no recruitment so additional measures of site suitability beyond species presence are needed to determine more suitable or higher quality habitats. In my research, I attempt to determine suitability of sites for Blanding’s Turtles across Michigan and Ohio using data collected from rapid assessment protocols fit into single season occupancy models with wetland and upland landcover types as co-variates of occupancy. To further determine the suitability of sites based on these data, I created single season occupancy models for juvenile Blanding’s Turtles and used N-mixture abundance modelling to determine relative abundance of Blanding’s Turtles at a site using the same landcovers as covariates of occupancy and abundance. Both modelling frameworks also allowed me to include detection covariates that could increase Blanding’s Turtle detection in future surveys. </p>
<p>Detection was largely influenced by Julian date with the highest probability of detection occurring from mid-May through late June. Length of trapping surveys was also found to influence Blanding’s Turtle detection with a substantial decrease in daily trap capture rates by the fourth trap night of a survey. Michigan occupancy and abundance models found that the most suitable sites in Michigan would have high percentages of high-quality upland forest and woody wetland landcovers, with the percentage of open water supporting the occupancy of turtles but having no discernable effect on abundance. Total upland forest also significantly increased the probability of juvenile occupancy in Michigan. In Michigan, I also observed that survey method can greatly influence the estimates of occupancy and abundance, and I determined that visual surveys cannot accurately determine these estimates. The heavily disturbed nature of Ohio’s landscape took away from the predictive power of landcovers used in my research for Blanding’s Turtle occupancy and abundance. The vast difference between occupied habitats in Michigan and Ohio also takes away from the predictive power of the regional level model and relative abundance of Blanding’s Turtle populations cannot be accurately determined at this scale using the spatial covariates I included. However, total undisturbed forest and total wetland proved to be positive covariates of Blanding’s Turtle abundance and occupancy for adult and juvenile turtles across both states, but the habitats used in each state vary greatly so future conservation decisions should be made on the state level as largest spatial scale. Using my models for Michigan suitable sites can be determined within the state and compare relative abundance between sites to determine healthier populations. For future analysis in Ohio, different, smaller scales spatial covariates should be used to explain differences in occupancy and abundance between sites.</p>
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Setting frequency relays and voltage relays to protect synchronous distributed generators against islanding and abnormal frequencies and voltagesBabi, Bombay 11 1900 (has links)
This study concerns frequency relays and voltage relays applied to the protection of
synchronous distributed generators operating in reactive power control mode without
a frequency regulation function. The effect of active and reactive powers combination,
load power factor, and reactive power imbalance are investigated for their implication
for the anti-islanding setting of the frequency relay. Results reveal that the effect of
these factors must be considered when setting the relay for islanding detection. For
the voltage relay, results reveal that the effect of active and reactive powers
combination, load power factor, and active power imbalance must be considered when
setting the relay for islanding detection. The effect of multi-stage tripping on the
frequency relay ability to detect island was also investigated. Results show that multistage
tripping can improve the anti-islanding performance of the frequency relay. / Electrical Engineering / M. Tech. (Electrical Engineering)
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Safeguards for Uranium Extraction (UREX) +1a ProcessFeener, Jessica S. 2010 May 1900 (has links)
As nuclear energy grows in the United States and around the world, the expansion
of the nuclear fuel cycle is inevitable. All currently deployed commercial reprocessing
plants are based on the Plutonium - Uranium Extraction (PUREX) process. However,
this process is not implemented in the U.S. for a variety of reasons, one being that it is
considered by some as a proliferation risk. The 2001 Nuclear Energy Policy report
recommended that the U.S. "develop reprocessing and treatment technologies that are
cleaner, more efficient, less waste-intensive, and more proliferation-resistant." The
Uranium Extraction (UREX+) reprocessing technique has been developed to reach these
goals. However, in order for UREX+ to be considered for commercial implementation, a
safeguards approach is needed to show that a commercially sized UREX+ facility can be
safeguarded to current international standards.
A detailed safeguards approach for a UREX+1a reprocessing facility has been
developed. The approach includes the use of nuclear material accountancy (MA),
containment and surveillance (C/S) and solution monitoring (SM). Facility information
was developed for a hypothesized UREX+1a plant with a throughput of 1000 Metric
Tons Heavy Metal (MTHM) per year. Safeguard goals and safeguard measures to be
implemented were established. Diversion and acquisition pathways were considered;
however, the analysis focuses mainly on diversion paths. The detection systems used in
the design have the ability to provide near real-time measurement of special fissionable
material in feed, process and product streams. Advanced front-end techniques for the
quantification of fissile material in spent nuclear fuel were also considered. The
economic and operator costs of these systems were not considered. The analysis shows
that the implementation of these techniques result in significant improvements in the
ability of the safeguards system to achieve the objective of timely detection of the diversion of a significant quantity of nuclear material from the UREX+1a reprocessing
facility and to provide deterrence against such diversion by early detection.
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