published_or_final_version / abstract / Earth Sciences / Doctoral / Doctor of Philosophy

The size of elk herds in Eastern Oregon has become a controversial issue. Trade-offs exist between the numbers of elk and domestic livestock on a given area of land, and also between elk and commercial timber harvesting policies. Disputes arise from differing views as to proper use of the natural resource base, specifically, public forested and grazing lands. Economic comparisons between elk and alternative uses of the land are complicated by the non-market nature of the elk resource, as this necessitates using a method to value the resource which may not be familiar to many decision makers. The objectives of this thesis were: (1) to analyze the demand for antlerless elk tags in eastern Oregon and to use the analysis to examine alternative pricing policies for allocating these antlerless tags, (2) to evaluate alternative elk management strategies from an economic perspective, and (3) to optimize societal benefits from the land base over time. Objective (1) was met by using the travel cost method. Results indicate that state hunting revenues would rise substantially if tag prices were increased so as to equilibrate quantities demanded and supplied. Objective (2) was met by using a computer simulation model to ascertain the impacts of harvesting and management policies upon the herd's stability and productivity. The results, placing emphasis on the antlerless animals, indicate that a slight reduction in current herd levels is economically desirable. This result is caused in part by the decreasing returns to scale from the elk herd as measured by total harvest per 1000 summer adult elk. Limitations of these conclusions with respect to bull elk demand are documented. Finally, objective (3) is met by formulating the dynamic relationships between elk, domestic livestock, and timber as a system of dynamic Lagrangian multipliers. This allows optimal inter-temporal allocation of resources by discounting future returns from these resources and equating marginal benefits of present and future use. The decision rules are examined, and economic implications of the multipliers are discussed. Although a theoretical model, some data is discussed, as are directions for future research. / Graduation date: 1983

I examined habitat use by desert bighorn sheep (Ovis canadensis medicana) in the Little Harquahala Mountains, Arizona from 1989 to 1992. I compared microsites used by male, female, and mixed-sex groups. I also compared use of microsites by sheep to random sites during the breeding and nonbreeding seasons. There were no differences in use of microsites between the breeding and nonbreeding seasons. However, microsites used by sheep had steeper slopes, more barrel cactus (Ferocactus wislizenii), higher topographic position, and more foothills palo verde (Cercidium microphyllum) than random sites. I examined seasonal diets. There were no seasonal differences between the diets of males and females. Brittle bush (Encelia farinosa), desert ironwood (Olneya tesota), fairy duster (Calliandra eriophylla), foothills palo verde, janusia (Janusia gracilis), Mormon tea (Ephedra torreyana), ratany (Krameria parvifolia), wild buckwheat (Eriogonum fasciculatum), grama grass (Bouteloua spp.), bedstraw (Galium spp.), borage (Borage spp.), and barrel cacti were present in diets all seasons. Barrel cactus is a seasonally important part of the diet, providing moisture during hot, dry periods. Forage selection is not a factor in the sexual segregation of desert bighorn sheep in the Little Harquahala Mountains. I examined habitat use by female sheep relative to the timing of parturition from 1989 to 1991. I compared range size and microsite habitat components of female sheep prior to and following parturition to random sites. Nineteen lambs were born to 10 females and 6 lambs survived $\ge$6 months. Lambs that died lived an average of 34 days. Five females did not raise any lambs that lived $\ge$6 months in any year. No female raised a lamb that lived $\ge$6 months 2 years consecutively. Females reduced their range sizes as lambing approached. Individual females used the same lambing areas repeatedly. Microsites used by female sheep were steeper and more rugged than random sites. Microsites used by females for 8 weeks after parturition had significantly less barrel cactus than was found at random sites. The traditional use of parturition sites in rugged terrain may outweigh the increased need for water by lactating females.

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High average wind speeds have been measured in many valleys. The reasons for these high winds are channelling effects of two physical origins, forced channelling and pressure driven channelling. In this study, the MIUU-model, a three-dimensional mesoscale model with a higher order closure, has been used to investigate these effects in idealised valleys. The simulations have been performed in both two- and three-dimensions with a multitude of conditions. The valley dimensions, as depth, width and length, have been changed in order to investigate the flow within the valley. The dependence of strength and direction of the geostrophic wind have also been examined. Most of the simulations are performed for wintertime conditions at high latitudes with low roughness. In addition, simulations representing summertime conditions are made to check the influence of the diurnal variation of incoming radiation and thermal stability. In the two-dimensional simulations the mean wind speed along the valley is found to be independent of the magnitude of the geostrophic wind (at least up to 10 ms-1) if the large-scale flow is perpendicular to the valley. In this case, only the pressure driven channelling effect is of importance. When the geostrophic wind is higher than10 ms-1, the valley winds are coupled to the ambient flow and gravity waves are affecting the results. The mean and maximum wind speeds are found to be a function of the valley depth. In a valley with a water body (a lake) at the bottom, the simulations gave higher within valley winds for lower water temperatures, which increases the stability. In the three-dimensional simulations, it is shown that the maximum valley winds are almost independent of the valley length. However, the mean valley wind speed is more affected. Furthermore, it was found that close to the area where the valley widens - towards the region with lower synoptic pressure - a wind maximum is found in all simulations. A simulation of the Torneträsk area was made to investigate the flow in a real topography. With geostrophic wind perpendicular to the valley, high wind speeds occur at low levels in accordance with measurements. For the conditions used, channelling effects dominated the within valley flow. / Sammanfattning av ”Modellering av vindklimatet i bergsdalar genom att använda MIUU-modellen”. Höga medelvindhastigheter har blivit uppmätta i många dalgångar. Skälen till att dessa vindar kan uppkomma är två olika kanaliseringstyper, tryckdriven - och tvingad kanalisering. I den här studien så har MIUU-modellen använts för att undersöka dessa effekter i olika typer av idealiserade dalgångar. Modellen är tredimensionell och använder sig av ett högre ordningens schema för att sluta ekvationssystemet rörande de turbulenta parametrarna. Simuleringarna har gjorts både i två och tre dimensioner med en mängd olika ingångsvärden. Dalgångens dimensioner, såsom djup, bredd och längd har ändrats och resultaten har jämförts för att kunna kartlägga vindfältet. Effekter av styrkan och riktningen på den geostrofiska vinden har också undersökts. De flesta simuleringarna är genomförda med vinterförhållanden på höga latituder och med låga värden på skrovligheten. Simuleringar med värden som ska representera sommarförhållanden, beträffande den inkommande strålningen och den termiska stabiliteten, är gjorda för att undersöka vindens dygnsvariation. De tvådimensionella simuleringarna ger att medelvinden längs dalgången är i det närmaste oberoende av den geostrofiska vinden styrka om den är riktad vinkelrätt mot dalen. I detta fall är bara tryckdriven kanalisering av betydelse. När den geostrofiska vinden är högre än 10 ms-1 blir vinden i dalgången mer direkt påverkat av gravitationsvågor som bildas över dalgången. Det är också framkommit att det finns ett beroende mellan max-medelvind och daldjup. I en dalgång med en en sjö i botten uppträder högre vindhastigheter speciellt för lägre vattentemperaturer. I de tredimensionella simuleringarna kan det ses att maxvinden är i det närmaste konstant oberoende dalgångslängd. Medelvinden däremot är mer påverkad och blir högre ju längre dalgången är. En annan slutsats som kan dras från de tredimensionella simuleringarna är att ett vindmax återfinns i anslutning till att dalgångens bredd ändras. Maximat är lokaliserat mot den sida av förträngningen som har ett lägre synoptiskt tryck. Simuleringar av Torneträskområdet är gjorda för att se hur vindfältet ser ut i verklig terräng. Med den geostrofiska vinden vinkelrät mot dalgången så uppträder höga vindhastigheter på låg nivå i dalgången vilket också är sett i mätningar. Under de simulerade förhållandena så dominerade kanalisering strömningen i dalgången.

In this thesis we study the thin-film type equations in one spatial dimension. These equations arise from the lubrication approximation to the thin films of viscous fluids which is described by the Navier-Stokes equations with free boundary. From the structural point of view, they are fourth-order degenerate nonlinear parabolic equations, with principal term from diffusion and lower order term from external forces. In Chapter one we study the dynamics of the equations when the external force is given by a power law. Classification of steady states of this equation, which is important for the dynamics, was already known. Previous numerical studies show that there is a mountain pass scenario among the steady states. We shall provide a rigorous justification to these numerical results. As a result, a rather complete picture of the dynamics of the thin film is obtained when the power law is in the range (1,3). In Chapter two we turn to the special case of the equation where the external force is the gravity. This is important, but, unfortunately not a power law. We study and classify the steady states of this equation as well as compare their energy levels. Some numerical results are also present. / Zhang, Zhenyu. / Asviser: Kai Seng Chou. / Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 103-107). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

許雪輝. / 稿本 ; 複本據稿本影印. / Thesis (M.A.)--香港中文大學硏究院藝術學部. / Gao ben ; fu ben ju gao ben ying yin. / Includes bibliographical references (leaves 224-259). / Xu Xuehui. / Thesis (M.A.)--Xianggang Zhong wen da xue yan jiu yuan yi shu xue bu. / 導言 / Chapter 第一章 --- 孔望山佛教造像題材之發現 / Chapter 甲 --- 孔望山之地理位置 --- p.6 / Chapter 乙 --- 歷代對孔望山造像題材及年代之認識 / Chapter （一） --- 文献記載 --- p.11 / Chapter （二） --- 近人考察 --- p.13 / Chapter 丙 --- 孔望山造像內容之概述 --- p.18 / Chapter 第二章 --- 孔望山造像年代問題述評 / Chapter 甲 --- 東漢說 --- p.36 / Chapter （一） --- 小結 --- p.44 / Chapter 乙 --- 非東漢說 / Chapter （一） --- 曹魏以後元魏以前說 --- p.53 / Chapter （二） --- 三國或西晉時代以後說 --- p.57 / Chapter （三） --- 六朝說 --- p.59 / Chapter （四） --- 唐代前後說 --- p.60 / Chapter （五） --- 小結 --- p.65 / Chapter 第三章 --- 從文献資料考察孔望山佛教造像的年代 / Chapter 甲 --- 從佛教起源及漢代譯經方面考察 / Chapter （一） --- 佛像之起源　 --- p.74 / Chapter （1） --- 小結 --- p.89 / Chapter （二） --- 漢代佛教譯經 --- p.92 / Chapter （1） --- 小結 --- p.100 / Chapter 乙 --- 從漢代海上交通及漢代佛法流佈之地理分佈方面考察 / Chapter （一） --- 漢代海上交通 / Chapter （1） --- 漢代海路已開 --- p.106 / Chapter （2） --- 漢代中印之海路交往 --- p.114 / Chapter （3） --- 《漢書、地理志》所載之航程 --- p.119 / Chapter （二） --- 漢代佛法流佈之地理分佈 --- p.122 / Chapter （1） --- 小結 --- p.136 / Chapter 第四章 --- 孔望山佛教造像及藝術特色之分析比較 / Chapter 甲 --- 孔望山佛教造像之圖像及藝術特色 --- p.139 / Chapter 乙 --- 孔望山佛教造像與中國早期佛教造像之圖像及藝術特色比較 / Chapter （一） --- 東漢佛教造像之圖像及藝術特色　　　 --- p.147 / Chapter （二） --- 魏吳晉間出土佛像的圖像及藝術特色 --- p.152 / Chapter （三） --- 孔望山佛教造像與中國早期佛教造像之圖像及藝術特色比較 / Chapter （1） --- 圖像方面 --- p.163 / Chapter （2） --- 藝術特色方面 --- p.165 / Chapter 第五章 --- 總結 --- p.171 / 注釋 --- p.178 / 書目 --- p.224 / 圖錄

Typescript (photocopy). / Digitized by Kansas Correctional Industries

The voluminous limnological literature contains few studies of mountain streams. Though there are a few papers on the benthic algae (see Budde 1928, Raabe 1951) only Pennak (1943) reports year-round quantitative data on the phytoplankton. Brinley (1950) gives some phytoplankton information in a summer study of streams in Rocky Mountain National Park.