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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

Heterogeneity in Hyporheic Flow, Pore Water Chemistry, and Microbial Community Composition in an Alpine Streambed

Nelson, Amelia Rose 28 August 2019 (has links)
No description available.
132

Vibration damping of alpine skis with implemented Flow Motion Technology / DÄMPNING AV VIBRATIONER I ALPINSKIDOR MED IMPLEMENTERAD FLOW MOTION TECHNOLOGY

Palmborg, John, Söderman, Hampus January 2019 (has links)
Flow Motion Technology AB has previously developed a technology to improve hockey skates and inlines. The technology called Flow Motion Technology (FMT) is utilizing the smooth and effective rolling motion of a human footstep, and has proven to be very successful after implementation in both hockey skates and inlines. Flow Motion Technology AB has interest in investigating whether the technology can be implemented in other sports applications, which this thesis project concerns. The project examines the implementation of FMT in the alpine skiing segment. The purpose is to provide Flow Motion Technology AB with a foundation for evaluating the potential of investing further in the development of FMT applied in alpine skiing. FMT is implemented in a feature positioned between ski and binding of most alpine race skis, commonly called a race plate. The work is divided into two parts; The first part covers the development and manufacturing of a prototype along with detailed description of the procedures and methods used. The second part is about the tests of the prototype’s vibration-damping properties carried out in laboratory environment along with analysis of the results. Initial field tests are also carried out followed by fundamental analysis. An existing plate intended for competition use is tested in parallel with the prototype and is used as a reference when analyzing the results. The results show that the ski equipped with the FMT plate dampened vibrations on an average of 27 % faster than the reference plate. Measurements was compiled for three damping intervals specified for the tests performed in laboratory. A statistically significant difference in all three cases was obtained. The measured maximum amplitude of the acceleration in the vibrations was also significantly lower for the ski implemented with the FMT plate compared to the reference plate. The eigen frequencies of the ski measured in laboratory were not significantly affected if the ski was fitted with the FMT plate or the reference plate. The eigen frequencies measured in field generally corresponded to the measured in laboratory, with the difference that they were offset on an average of 7 Hz higher in field. / Flow Motion Technology AB har tidigare utvecklat en teknologi för att förbättra hockeyskridskor och inlines. Teknologin kallad Flow Motion Technology (FMT) utnyttjar den naturliga och effektiva rullande rörelse i en människas fotsteg, och har efter implementation i hockeyskridskor och inlines visat sig vara framgångsrik. Flow Motion Technology AB vill undersöka om denna teknologi kan implementeras i andra idrottssammanhang för att utvärdera möjligheter att bredda företagets affärsområde. Detta examensarbete är en del av denna undersökning, och i denna rapport beskrivs implementationen av FMT i segmentet alpinskidåkning. Syftet med projektet är att förse Flow Motion Technology AB med underlag för att utvärdera lönsamheten i att investera mer i utvecklingen av FMT riktad mot alpinskidåkning. FMT implementeras i projektet i en raceplatta, en komponent monterad mellan skida och bindning. Arbetet är uppdelat i två delar; utveckling och tillverkning av en funktionsprototyp med detaljerad beskrivning av tillvägagångssätt och metoder, samt tester av prototypens vibrationsdämpande prestanda i labbmiljö med tillhörande analys av resultat. Initiala tester utförs även i fält med enklare analys av resultat. En befintlig bindningsplatta avsedd för tävling testas parallellt med den utvecklade plattan och används som referens vid analys av resultaten. Resultaten visar att plattan implementerad med FMT dämpade en skidas vibrationer i genomsnitt 27 % snabbare än vad referensplattan gjorde vid de tre dämpningsintervall som specificerats för testen i labbmiljö. En statistiskt signifikant skillnad i alla tre fall. Den uppmätta maxamplituden för accelerationen i vibrationerna var även statistiskt signifikant lägre för skidan implementerad med FMT jämfört med referensplattan. Egenfrekvenserna uppmätta i labb påverkades inte nämnvärt om skidan var monterad med FMT-plattan eller referensplattan. De egenfrekvenser som uppmättes i fält motsvarade generellt de som uppmättes i labb med skillnaden att de var förskjutna till att i genomsnitt vara 7 Hz högre.
133

Vývoj německých alpských spolků v Českých zemích do roku 1938 / Development of German Alpine Clubs in Czech Lands until 1938

Chaloupská, Pavlína January 2014 (has links)
Mgr. Pavlína Chaloupská, abstrakt disertační práce Abstract: The thesis analyzes activities of the most important German Alpine clubs operating in the Czech Lands and interwar Czechoslovakia since their establishment until 1938. The history of alpine clubs is explained, and the organization of DuÖAV (Deutscher und Österreichischer Alpenverein, German and Austrian Alpine Association) is analysed, on the basis of general and specific introductory information related to the alpinism in the late 19th century. The thesis is divided according to geographical location of the constituent sections. For each section of DuÖAV, the circumstances of its establishment are monitored, the sphere of its activity is defined, the internal organization is described, and the economic functioning is analyzed. The activities of Alpine clubs in Bohemia and Alps are charted in detail, and based on the research it was discovered that the most important activity of the Alpine clubs was the construction of the Alpine huts, owned by German clubs from Bohemia. Among other activities there were organization of guiding and rescue operations, giving lectures, balls and excursions in their locality. Two chapters are devoted to the most important personalities of the German alpinism in the Czech lands: Johann Stüdl and Rudolf Kauschka.
134

Monitoring of Foraging Sites for Ungulates within Alpine Plant Communities and Establishment of Long-Term Monitoring Plots for Rare Castilleja parvula var. parvula in the Tushar Mountains, Utah

Shipp, Heather 14 April 2022 (has links)
The Tushar Mountains of Utah provide essential alpine habitat to a variety of flora and fauna, including 27 endemic plant species and several ungulates (mountain goats, deer, elk, cattle). These ungulates were observed throughout two growing seasons and field analyses were conducted to assess foraging selection. Overall, most ungulates, especially large nursery herds, tended to prefer foraging amongst alpine regions within the Bullion volcanic of the Tushars, which is characterized by denser vegetation than the Belknap volcanic region. Mountain goats and deer were most frequently observed foraging within the Tushar alpine habitat; however, elk and domestic cattle were also observed. Mountain goats preferred foraging at higher elevations than other ungulates and shared the most dietary overlap with deer. Out of the 27 plant species endemic to this region, only Castilleja parvula var. parvula, commonly known as the Tushar paintbrush, was encountered frequently utilized by ungulates. This plant species was also observed being eaten by a variety of rodents and lagomorphs. Long-term monitoring plots were established in four different populations of C. parvula var. parvula across the Bullion volcanic range of the Tushars. These plots were revisited on a yearly basis and used to ascertain demographic data, which will shed light on population trends over time. A variety of different measurements were used to better understand the biology and habitat requirements of this rare plant species. Although the four monitored populations share many similarities, they each have their own site characteristics, local densities, relative plant communities, and potential threats. Further monitoring is necessary to better understand trends and assess the level of the various threats to C. parvula var. parvula populations.
135

American Pika (Ochotona princeps): Persistence and Activity Patterns in a Changing Climate

Massing, Cody P 01 May 2012 (has links) (PDF)
An increasing amount of evidence suggests that as temperatures increase, montane animals are moving upward in elevation (IPCC 2007, Parmesan and Yohe 2003). As suitable habitats rise in elevation and then disappear altogether, these animals could be pushed to extinction. The American pika, Ochotona princeps, is a montane mammal that lives in western North America, usually at elevations above 1500 m (Smith and Weston 1990). Recent evidence suggests that pika population numbers are dropping in response to rising temperatures (Beever et al. 2010). The pika is a small herbivorous lagomorph, a relative of hares and rabbits. Its habitat is tightly restricted to talus slopes (rockfields) and the surrounding vegetation (Grayson 2005). Pikas have a high tolerance for cold temperatures, and do not hibernate during the long montane winter. However, they have very little tolerance for even mildly warm temperatures, and have been found to die when confined above ground at 25.5˚ C (Smith 1974b). To better understand pika persistence, we resurveyed 17 historic pika sites in the Lassen Peak region of northern California in August and September, 2009. Six of the historic sites were abandoned, as well as an additional 11 of 17 new sites surveyed. At each site we collected habitat information, and analyzed the data for factors that were correlated with site occupancy. We also installed 38 iButton thermal dataloggers in abandoned and occupied pika use sites, to determine if temperature affects occupancy. The dataloggers remained in pika sites for 14 months and recorded temperature every 1.5 hours. Abandoned pika sites had higher average temperatures and more days below 0˚ C. They also had greater shrub cover, less forb and graminoid cover, and a greater percentage of litter substrate. These findings suggest that the current warming trend may be having a negative impact on pikas in the Lassen Peak Region. As temperatures rise, pikas may be declining due to unsuitable temperatures and altered vegetative communities. In addition to the Lassen surveys, I investigated pika behavior in different temperature regimes in the Sierra Nevada. If pikas are able to adapt to climate change, it is possible that populations of pikas in different temperature regimes may exhibit behavioral plasticity, or have evolved genetic differences, such that these populations have different daily activity schedules. To determine if there is a difference in pika behavior at different elevations I observed pikas in one low and one high elevation site within the Bishop Creek drainage system in the Sierra Nevada. I conducted behavioral observations of pikas in four time blocks throughout the day in August and September, 2010. I recorded specific behaviors, such as foraging and haying (vegetation collecting), and compared these activities between low and high elevation pikas at different times of day. In August, pikas in the low elevation site exhibited a different activity profile than those in the high elevation site. Low elevation pikas were significantly more crepuscular (most active at dawn and dusk) during this month. I also observed more foraging behavior in the high elevation than the low elevation site, in both August and September. Reduced activity at higher temperatures may have negative impacts on pikas as temperatures increase. Low elevation pikas may be stressed due to reduced time spent foraging and haypile (overwinter vegetation cache) gathering. However, if pikas were able to switch their activity schedules to a more nocturnal schedule, they could escape higher daytime temperatures. To detect the possibility of nocturnal behavior in low elevation pikas, I set up four infra-red remote cameras in the low elevation site. I had variable success in capturing pika behavior with the cameras, and detected no evidence of nocturnal behavior. More research on the possibility of nocturnal behavior in pikas would be worthwhile, in part to determine what chance, if any, pikas have of adapting to rising global temperatures.
136

Detailed simulation of storage hydropower systems in the Italian Alpine Region

Galletti, Andrea 11 June 2020 (has links)
The water-energy nexus holds paramount relevance in the context of the transition to a carbon free energy system, being water the only renewable energy source with reliable storage capacity. Modelling hydropower production in a large domain over a long time window represents an open challenge due to a variety of reasons: firstly, high-resolution, large-scale hydrological modelling in a context of uncertainty needs calibration, thus representing a computationally intensive task due to the large domain and time window over which calibration is needed; secondly, as stated by many works in literature, hydropower production modelling and in particular reservoir modelling is a very information-demanding procedure, and excessive simplifications adopted to face the lack of information might lead to consistent bias in the predictions. This thesis can be subdivided into three main parts: firstly, the model that was used to perform every analysis, HYPERstreamHS, will be presented. The model is a continuous, large-scale hydrological model embedding a dual-layer MPI framework (i.e. Message Passing Interface, a common standard in parallel computing) that ensures optimal scalability of the model, greatly reducing the computation time needed. Explicit simulation of water diversions due to hydropower production is also included in the model, and adopts only publicly available information, making the model widely applicable. Secondly, a first validation of the model will be presented, and the adopted approach will be compared with some other approaches commonly found in literature, showing that the inclusion of a high level of detail is crucial to ensure a reliable performance of the model; this first application was performed on the Adige catchment, where extensive information on human systems was available, and allowed to effectively assess which information were indispensable and which, in turn, could be simplified to some extent while preserving model performance. Finally, the model setup has been applied on a relevant portion of the Western Italian Alps; in this case, two different meteorological input forcing data sets were adopted, in order to assess the differences in their performance in terms of hydropower production modelling. This latter study indeed represents a preliminary analysis and will provide stepping stone to extend the modelling framework to the Italian Alpine Region.
137

The 2010 Winter Olympics: A Mixed-Methods Investigation of the Hotel Industry and Tourism in the Demographic Clusters metro–Vancouver versus the alpine–Resort Whistler

Van der Heyden, Leonard J. January 2014 (has links)
In this thesis, applying an innovative postmodern equal-weight/sequential QUAN→PHEN Mixed-Methods Phenomenological Research (‘MMPR’) approach to study an Olympics’ impact within its two-cluster socio-demographic footprint forms its main contribution to knowledge. Facilitating between-methods triangulation is a novel eclectic pragmatic approach that is used to capture the richness of thematic data flowing from in-depth, open-ended interviews with most – 62 in all – senior Hoteliers spread evenly between distinct urban Metro-Vancouver and rural alpine-Whistler, whilst concurrently capitalizing on the availability of a unique BC Stats proprietary micro-municipal-level secondary data source, i.e., British Columbia’s ‘Additional Hotel Room Tax’ (‘AHRT’). Typically, traditional mono-method-positivist neo-classical economic syntheses are used to quantify an Olympic Games’ ex-ante or ex-post impact. This study’s findings confirm that such syntheses attempts, at the micro-municipal level, lead to inevitable dead-ends. At a sub-national level of micro-granularity, using available economic models is an impossible task due to the insurmountable practical problem of complete lack of, or paucity, of data. When applied to assess mega-events, such modelling is shown to lack credibility; models are insufficiently comprehensive or its users consciously engage in ‘shenanigans’ by force-fitting input/output to produce pre-ordained outcomes for political expedience and meeting agency interests. The ‘MMPR’ approach acknowledges and respects the established and ‘current-thinking’ paradigmatic epistemological and ontological perspectives. ‘Hotel Activity’, measured via ‘AHRT’, is substituted as a ‘Proxy’ for ‘Tourism’ following empirically establishing these three variables as highly correlated. Prevalent academic findings of negative impacts from Winter Olympics are not borne out. Phenomenological issues of ‘illusory correlations’ and ‘data saturation’ are addressed.
138

CAUSES AND CONSEQUENCES OF VARIATION IN UV TRANSPARENCY FOR FRESHWATER ECOSYSTEMS

Rose, Kevin C. 03 May 2011 (has links)
No description available.
139

Population Structure and Biophysical Density Correlates of Whitebark Pine (Pinus albicaulis) at Two Treelines in the Northern Rocky Mountains

Slyder, Jacob Brake 05 June 2012 (has links)
This study analyzes the structure and biophysical correlates of density of two whitebark pine (Pinus albicaulis) populations in the northern Rocky Mountains. Whitebark pine is a keystone species and an important component of treeline ecosystem dynamics; however, subalpine populations have declined nearly rangewide in recent decades. Though declines in subalpine forests have been well documented in the literature, few studies have assessed population structure and habitat requirements at treeline. Various disturbances have combined to impact whitebark pine populations across its range, but the primary threat at treeline sites in the northern Rocky Mountains is white pine blister rust, caused by the exotic fungal pathogen Cronartium ribicola. In this study, I aim to: 1) assess population structure and regeneration within two geographically different treelines experiencing contrasting levels of infection, and 2) examine associations among several biophysical variables and whitebark pine density to better understand treeline habitat variability and regeneration patterns. I used density-diameter curves and non-parametric Kruskal-Wallis tests to compare population structure between sites, and developed generalized linear mixed models to assess correlations between whitebark pine density and biophysical site variables. The results demonstrate that despite very different ecosystems and blister rust infection rates, our two study sites have similar population structure. Our model results highlight marked differences between populations in terms of biophysical correlates of density. While correlations are similar within site, seedlings and saplings have stronger correlations with biophysical variables than established trees. / Master of Science
140

Theory Meets Terrain: Advancing the Alpine Fault Insights with Seismic Anisotropy Inversion

Oumeng Zhang (18333576) 10 April 2024 (has links)
<p dir="ltr">The Alpine Fault, located in the South Island, New Zealand, is a subject of intense geological study due to its potential to trigger large earthquakes. It encompasses a complex system with the interplay of mechanics, thermodynamics, and fluid. Gaining insights into these systems not only enhances our understanding of the fault but also holds the potential to guide risk mitigation efforts.</p><p dir="ltr">The damage extent and fracture networks within the metamorphic rock mass adjacent to the fault can be effectively characterized by seismic anisotropy, an elastic property of rock, where seismic waves travel at different speeds with variation directions. This thesis presents a comprehensive exploration of seismic anisotropy in the hanging wall immediately adjacent to the principal slip zone of the Alpine Fault in New Zealand. Leveraging the borehole seismic data from a unique scientific drilling project and advanced numerical modeling techniques, the ultimate goal is to invert and parameterize the bulk seismic anisotropy.</p><p dir="ltr">Motivated by these challenges, the thesis undertakes several key initiatives: The first effort focuses on gaining a comprehensive understanding of an innovative method for seismic measurement: Distributed Acoustic Sensing (DAS) – examining its operational principles, factors influencing observed wavelets, and how it contrasts with traditional point sensors for accurate interpretation. Subsequently, the research introduces the implementation of an open-source seismic wave solver designed for modeling elastic wave propagation in complicated anisotropic media. This solver is further optimized for computational efficiency with its performance rigorously benchmarked.</p><p dir="ltr">With this preparedness, the inversion is further facilitated by high-performance computing (HPC) and a deep-learning algorithm specifically designed for automatically picking transit times. The inverted bulk elastic constants, compared to the intact rock, reveal 28% to 35% reductions in qP-wave velocity, characterizing the damage due to mesoscale fracture. Further analysis sheds light on the existence of orthogonal fracture sets and an intricate geometrical arrangement that agree with the previous borehole image log. This represents an advancement in our ability to characterize and understand the geologic processes with seismic anisotropy.</p>

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