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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Seasonal range analysis for white-tailed deer on the Broad Run Wildlife Research Area

Morris, Karen Irene January 1974 (has links)
The mixed oak-pine cover type was evaluated as white-tailed deer range on four study areas by measuring dry matter production of key forages and determining their nutrient composition. Composite diets containing plant species which represented the major portions of each seasonal diet as indicated by food habits studies, were mixed for the summer, fall and winter seasons. For the spring flush and spring seasons, individual key forages were analysed. All samples were assayed for soluble carbohydrates, lignin, phosphorus, gross energy, proximate composition, and in vitro dry matter digestibility. Digestible energy production in kcal/ha/day was calculated seasonally for key forages. The ratios of digestible energy available in key forages to that required by the estimated deer herd were 3.01, 5.94, 0.96, 2.14, and 1.23, for the spring flush, spring, summer, fall, and winter, respectively. These ratios indicate the potential of the study areas to support the estimated population density of 1 deer per 16.4 ha. The mixed oak-pine cover type appears to be adequate to support the estimated deer herd if 50 percent of the key forages are consumed seasonally but inadequate if only 25 percent are used. During all seasons, forage protein appeared to be adequate and phosphorus was possibly lower than that required for optimal animal performance. / Master of Science
172

Establishing genetic and physiological baselines for the black-tailed prairie dog (Cynomys ludovicianus).

Biggs, Cindy Dawn 05 1900 (has links)
The black-tailed prairie dog (Cynomys ludovicianus) has experienced dramatic declines over much of its historical range due to habitat loss, plague, poisonings, and shootings. Many populations now occur as isolated genetic relicts. A multiple locus genetic profile was obtained using microsatellite analyses of six polymorphic nucleotide repeats from 319 black-tailed prairie dogs collected from 16 colonies throughout the state of Texas. This assessment revealed that existing populations have sufficient variation at all six loci to verify the usefulness of this approach as a primary genetic tool in conservation and preservation. The data reveals regional-dependent frequency patterns as well as support for founder/bottleneck effects for several of the 16 sites. Although the prairie dog population in Texas as a whole may appear genetically diverse, considerable genetic divergence has already occurred among the subpopulations (FST = 0.164). Isolation by distance is supported by genic differentiation analysis (P < 0.001) and pairwise correlation analysis between genetic distance and geographic distance (P < 0.001). Prairie dogs from six (COC, LUBA, LUBC, LUBD, LUBE, and TAR) of the original 16 sites have been relocated or exterminated, or were in the process of being relocated. Results indicated the following colonies (COT, DAL, HOW, and HUD) are of sufficient size and possess ample genetic diversity to be characterized as candidate foundation populations for future preservation efforts. The proximity of small colonies (< 20 hectares) such as HEMB, LUBB, and PEC, to other colonies should be examined to determine if they are isolated or part of a metapopulation. Colonies (HAR, HEMA, and SCH) with low genetic diversity would be ideal candidates for supplementation. Alternatively, these colonies could be relocated or blended with other similar but genetically distinct colonies. Baselines for healthy, pet prairie dog hematology and blood chemistries were also established. Results signify that data gathered from pet prairie dog blood analyses should be referenced against hematology and blood chemistry baselines established using pet prairie dog subjects.
173

Statistické odhady a chvosty jejich rozdělení pravděpodobností / Statistické odhady a chvosty jejich rozdělení pravděpodobností

Veverková, Jana January 2012 (has links)
Master Thesis Statistical estimators and their tail behavior provides description of two type of characteristics of robustness of estimators - tail behavior and break- down point. Description is made for translation equivariant estimators in general and also for some concrete type of estimators, sample mean, sample median, trimmed mean, Huber estimator and Hodges Lehmann estimator. Tail behavior of these estimator is illustrated for random sample coming from t-distribution with 1 to 5 degrees of freedom. Ilustration is based on simulations made in Mathematica. 1
174

Factors influencing food availability for the endangered south-eastern red-tailed black cockatoo Calyptorhynchus banksii graptogyne in remnant stringybark woodland, and implications for management

Koch, Paul. January 1900 (has links)
Thesis (Ph. D.)--University of Adelaide, 2005. / Title from PDF title page (viewed on July 9, 2005). Includes bibliographical references (p. 138-146).
175

Studies on Asymptotic Analysis of GI/G/1-type Markov Chains / GI/G/1型マルコフ連鎖の漸近解析に関する研究

Kimura, Tatsuaki 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第20517号 / 情博第645号 / 新制||情||111(附属図書館) / 京都大学大学院情報学研究科システム科学専攻 / (主査)教授 髙橋 豊, 教授 太田 快人, 教授 大塚 敏之, 准教授 増山 博之 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
176

The Influence of Local Forage Variability on White-tailed Deer (Odocoileus virginianus) Body Size at Fort Hood, Texas

Eddins, Amy C. 12 1900 (has links)
Nutritional quality and availability is thought to regulate geographic patterns of variability in animal body size due to phenotypic plasticity. The purpose of this study is to determine how vegetation quality, abundance and population density influence white-tailed deer (Odocoileus virginianus) body size on a subregional spatial scale at Fort Hood, Texas. Harvest and census records are used to test the hypothesis that white-tailed deer exhibit phenotypic plasticity (e.g. larger body size) in response to differences in vegetation quality and availability. Results from these analyses suggest that forage quality and abundance alone is not a main driver of white-tailed deer body size. Analysis of deer population density (generally) resulted in an inverse relationship with body size. Areas with high quality forage and low population density support larger deer while areas with low quality forage and high density support smaller than average deer. The few exceptions occur in areas exhibiting poor quality forage and low population density or high forage quality and high density. Results from this study suggest that continued overcrowding of deer within isolated areas may eventually lead to efficiency phenotypic conditions producing smaller sized deer. These results could prove useful in interpreting deer population responses to harvest management. For successful local management of deer, studies examining the combined influence of habitat variables (such as forage quality, abundance and population density) on deer health offer managers valuable information needed to establish annual harvest goals and understand deer-habitat relationships relative to carrying capacity.
177

Use of geographic information systems and infrared-triggered cameras to assess white-tailed deer (Odocoileus virginianus) habitat in Denton County, Texas.

Sallee, David R. 08 1900 (has links)
This study utilized geographic information systems, remote sensing, and infrared-triggered cameras to assess white-tailed deer habitat in Denton County, Texas. Denton County is experiencing tremendous growth in both population and development. Despite their presence here historically, white-tailed deer were all but extirpated by the beginning of the 20th century, and there are no data available which support their presence in Denton County again until the 1980's. This study attempts to equate the increase in white-tailed deer population to Denton County's transformation from an agricultural to an urban economy and lifestyle. Eighteen sites were chosen throughout the county to research the following metrics: geology, soils, landcover, landscape ecology, streams, shorelines, land use, population, roads, structures, and census methods.
178

A paleozoological perspective on predator extermination and white-tailed deer (Odocoileus virginianus Boddaert) overabundance in central Texas.

Wolverton, Steven J. 05 1900 (has links)
Archaeological and paleontological datasets are used in conservation to add time-depth to ecology. In central Texas several top carnivores including prehistoric Native American hunters have been extirpated or have had their historic ranges restricted, which has resulted in pest-level white-tailed deer (Odocoileus virginianus texana) populations in some areas. Predator extermination has dramatically reduced the average body size of members of the extant predator guild, and large carnivores most capable of hunting white-tailed deer are extirpated. Character release in the remaining “large” predatorsmesocarnivoresis a predicted outcome related to the adaptive vacuum at the top of the trophic hierarchy. Differences in body size of deer between prehistory and modernity are expected given that a lack of predation likely has increased intraspecific competition for forage among deer resulting in smaller body size today. In fact modern deer from settings without harvest pressure are significantly smaller than those from harvested areas and from prehistoric deer. From a natural history perspective, this research highlights potential evolutionary causes and effects of top-predator removal on deer populations and related components of biological communities in central Texas.
179

Robust Control Charts

Cetinyurek, Aysun 01 January 2007 (has links) (PDF)
ABSTRACT ROBUST CONTROL CHARTS &Ccedil / etiny&uuml / rek, Aysun M. Sc., Department of Statistics Supervisor: Dr. BariS S&uuml / r&uuml / c&uuml / Co-Supervisor: Assoc. Prof. Dr. Birdal Senoglu December 2006, 82 pages Control charts are one of the most commonly used tools in statistical process control. A prominent feature of the statistical process control is the Shewhart control chart that depends on the assumption of normality. However, violations of underlying normality assumption are common in practice. For this reason, control charts for symmetric distributions for both long- and short-tailed distributions are constructed by using least squares estimators and the robust estimators -modified maximum likelihood, trim, MAD and wave. In order to evaluate the performance of the charts under the assumed distribution and investigate robustness properties, the probability of plotting outside the control limits is calculated via Monte Carlo simulation technique.
180

The spatial analysis of radiocarbon databases the spread of the first farmers in Europe and of the fat-tailed sheep in Southern Africa /

Russell, Thembi M. January 2004 (has links)
Based on Ph. D. Thesis--University of Southampton, 2002. / Includes bibliographical references.

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