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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.
131

Contributing Factors to the Success of Small-Scale Diversified Farms In the Mountain West

Shepherd, Mary 01 May 2014 (has links)
This study uses ordered logistic regression models with data collected from eighty-six online surveys completed by small-scale producers in Utah, Idaho, Colorado, Nevada, and Wyoming to assess factors which most contribute to the overall success and profitability of small-scale diversified farms. Results indicate success and profitability may be partially explained by the number of acres owned/leased, use of wholesale outlets, farming as a primary occupation, years of experience, and use of outside business related services. Results may be useful as they indicate producer and operation characteristics that are lead to more profitable and successful operations and thus indicate areas in which a producer may most improve his or her business.
132

The Role of Cold Acclimatization on the Biogeography of the Mountain Chickadee (Parus Gambeli) and the Juniper Titmouse (Parus RIdgway)

Cooper, Sheldon J. 01 May 1997 (has links)
Biogeographic patterns of animals are shaped by biotic interactions, such as competition, and by abiotic factors, such as climate. Mountain Chickadees (Parus gambeli) and Juniper Titmice (Parus ridgway) are permanent residents of regions of western North America and are ecologically similar, but have different northern range limits. l measured several physiological variables, including basal metabolic rate (BMR), peak metabolic rate (PMR = maximal thermogenic capacity), metabolic response to varying environmental temperature (MRT), evaporative water loss (EWL), and daily energy expenditure (DEE) for summer-and winter-acclimatized Mountain Chickadees and Juniper Titmice to determine if seasonal and interspecific variation in cold tolerance and thermogenic ability shape the northern range distribution of these two species. In addition, I examined the ecological consequences of nocturnal hypothermia and cavity roosting in seasonally acclimatized Mountain Chickadees and Juniper Titmice. Winter birds tolerated colder test temperatures than summer birds for both species This improved cold tolerance was associated with a significant increase in PMR in winter chickadees (27.1 %) and titmice (114%) compared to summer. BMR was significantly higher in winter birds (16.0%) compared to summer birds for both species. BMR and PMR were significantly higher for chickadees compared to titmice in both summer and winter. Winter chickadees were able to withstand colder test temperatures than winter titmice. The Mountain Chickadee's lower critical temperature is lower than the Juniper Titmouse's in summer and in winter. The Mountain Chickadee's upper critical temperature is also lower than the Juniper Titmouse's and chickadees also had significantly higher evaporative water loss rates compared to titmice. Seasonal acclimatization in Mountain Chickadees involves insulatory as well as metabolic changes. For Juniper Titmice winter acclimatization appears to be primarily a metabolic process. The laboratory metabolism data for activity costs associated with DEE revealed that foraging energy requirements were not significantly higher than alert perching energy requirements. DEE was significantly higher (P<0.05) in winter-acclimatized chickadees and titmice compared to their summer counterparts. The marked increase in calculated DEE in winter birds compared to summer contrasts a pattern of increased DEE in the breeding season for several avian species. The data from this study indicate that the northern range limit of small birds can be limited by energetic and water balance demands.
133

Habitat use and population characteristics of bighorn sheep on Hart Mountain National Antelope Refuge, Oregon

Payer, David Carl 15 May 1992 (has links)
Graduation date: 1993
134

A Novel System for the Measurement of Dynamic Loading on a Bicycle Frame

Consell, Ryan January 2013 (has links)
The design of bicycle frames has remained fairly static for the majority of the past century, but recent increases in demand for high performance bicycles has created an accelerated design cycle that requires innovation. In order to design new frames with confidence in their capacity to withstand the rigors of use, reliable data about the nature of that use is needed, but this data is not currently available. The purpose of this research was to develop and implement a system that is capable of interpolating loads applied to a bicycle frame during vigorous riding for the purpose of improving the quality of information available to bicycle designers. The system that was developed employed finite element modeling to locate strain gauges on a frame and a least-squares approximate solution of strain readings to interpolate the applied loads. At its best, the system is capable of resolving loads with better than a 2% error. This system is limited, though, as it can only be applied in cases where the frame has a significant strain reaction to a load case but does not have a significant change in geometry during loading. This system was implemented on a cross-country mountain bicycle frame for the purposes of determining a rider weight to load relationship and to compare the standardized test procedures for bicycles to the loads experienced in the field. It was confirmed that there is a linear relationship between rider weight and load on the frame for all component forces except that applied to the bottom bracket, out of plane with the bicycle frame. It was also found that the British Standards fatigue testing practices, which are used internationally to assess bicycle safety, are inconsistent in their representation of realistic riding conditions when compared with the results from the field tests. Some loads appear conservative, some offer a very large factor of safety, and two are not represented at all. In particular, the moment about the bottom bracket due to pedaling and the load on the seat from the rider appear to consistently exceed the standardized test requirements while the moment caused by fork splay seems much smaller than the tests demand.
135

When Does A Stream Gain The Ability To Create Its Own Channel? A Field Study In Northwest Georgia On The Conasauga River

Srymanske, Roy H 05 April 2013 (has links)
Rivers are said to be self-shaping when a stream is able to create its own morphological features. This occurs when bankfull Shields stress (τbf*) is greater than reference Shields stress (τr*). Shields stress in the channel is affected during upstream progression by the height and width of the water decreasing, the slope becoming steeper, and the bed material becoming coarser. Bankfull Shields stress decreased progressing upstream while reference Shields stress increased due to increased slope. The self-shaping portions of the Conasauga occur in areas where the relative roughness of the bed material is fully submerged or greater than 5. Once the relative submergence is no longer fully submerged the stream channel no longer produces enough bankfull Shields stress to overcome the reference Shields stress. This occurs about midway through the study. This study allows better classification of streams using Shields stress and better understanding of channel processes for hydrologic engineering.
136

Two Problems in Computational Wave Dynamics: Klemp-Wilhelmson Splitting at Large Scales and Wave-Wave Instabilities in Rotating Mountain Waves

Viner, Kevin Carl 2009 December 1900 (has links)
Two problems in computational wave dynamics are considered: (i) the use of Klemp-Wilhelmson time splitting at large scales and (ii) analysis of wave-wave instabilities in nonhydrostatic and rotating mountain waves. The use of Klemp-Wilhelmson (KW) time splitting for large-scale and global modeling is assessed through a series of von Neumann accuracy and stability analyses. Two variations of the KW splitting are evaluated in particular: the original acousticmode splitting of Klemp and Wilhelmson (KW78) and a modified splitting due to Skamarock and Klemp (SK92) in which the buoyancy and vertical stratification terms are treated as fast-mode terms. The large-scale cases of interest are the problem of Rossby wave propagation on a resting background state and the classic baroclinic Eady problem. The results show that the original KW78 splitting is surprisingly inaccurate when applied to large-scale wave modes. The source of this inaccuracy is traced to the splitting of the hydrostatic balance terms between the small and large time steps. The errors in the KW78 splitting are shown to be largely absent from the SK92 scheme. Resonant wave-wave instability in rotating mountain waves is examined using a linear stability analysis based on steady-state solutions for flow over an isolated ridge. The analysis is performed over a parameter space spanned by the mountain height (Nh/U) and the Rossby number (U/fL). Steady solutions are found using a newly developed solver based on a nonlinear Newton iteration. Results from the steady solver show that the critical heights for wave overturning are smallest for the hydrostatic case and generally increase in the rotating wave regime. Results of the stability analyses show that the wave-wave instability exists at mountain heights even below the critical overturning values. The most unstable cases are found in the nonrotating regime while the range of unstable mountain heights between initial onset and critical overturning is largest for intermediate Rossby number.
137

Design of Rear Suspension Mechanisms of Mountain Bikes

Chen, Cheng-Sheng 14 July 2000 (has links)
­^¤åºK­n The purpose of this work is to provide a design procedure of rear suspension mechanisms of mountain bikes by using the concept of engineering design method. First, the conditions and particularities of mountain biking are investigated and the performance specification of rear suspension mechanisms is set by focusing the investigations on the requirements of rear suspension mechanisms. Second, the requirements and constraints of generating different types of rear suspension mechanisms are developed and the systematic process of creative mechanism design is followed. Third, the different types of rear suspension mechanisms resulted from creative mechanism design are analyzed to realize the property of each type of rear suspension mechanisms and the procedure of kinematic design is developed by using the algorithm of heuristic combinatorial optimization method. Finally a computer aided design program written in Visual BASIC 6.0 programming language is developed to be the powerful tool of performance analysis and kinematic design of rear suspension mechanisms.
138

Design on the System of Rear Suspension Mechanisms of Mountain Bikes

Hwang, Ruey-Horng 04 July 2001 (has links)
With the prevalence of leisure sport, riding mountain bikes becomes an enormous vogue today. The mountain bikes undoubtedly have become one of the most popular products in the leisure sport market. Based on its superior standard of operating quality and the demand of comfortableness, the requirement of the outstanding rear suspension mechanism of mountain bikes is one of the crucial components in the design procedure. The purpose of this work is to provide a design procedure of the system of rear suspension mechanisms of mountain bikes by using the concept of engineering design method. First, to investigate the essential requirements of the system of rear suspension mechanisms of mountain bikes is started. Then the design targets of this research are decided further in order to establish the requirement book for the system of rear suspension mechanisms of mountain bikes. Second, the kinematic design of rear suspension mechanisms is proceeding. Computer Aided Tried and Error program is utilized for synthesizing the dimensions of rear suspension mechanisms to meet the requirement of functions. Finally, topology theory is applied to synthesize the frames of mountain bikes. Furthermore, the systematic design procedure is developed to perform the embodiment design of the system of rear suspension mechanisms of mountain bikes.
139

The dissolution rate of unirratiated UO₂ under repository conditions the influence of fuel and water chemistry, dissolved oxygen, and temperature /

Casella, Amanda J., Miller, William Hughes, Hanson, Brady D. January 2008 (has links)
Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 24, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation supervisors: Dr. William H. Miller, Dr. Brady D. Hanson. Vita. Includes bibliographical references.
140

Untersuchungen über die blattanatomie von alpen- und ebenenpflanzen. ...

Lohr, Paul Louis, January 1919 (has links)
Inaug.-diss.--Basel. / Vita. "Separatabdruck von dem "Recueil des travaux botaniques neérlandais", volume XVI, livraison I, 1919." "Literatur-verzeichnia": p. [58]-59.

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