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Application of Passive and Active Microwave Remote Sensing for Snow WaterEquivalent EstimationPan, Jinmei 26 October 2017 (has links)
No description available.
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A GIS MODEL TO ESTIMATE SNOW DEPTH USING DIFFERENTIAL GPS AND HIGH-RESOLUTION DIGITAL ELEVATION DATAHURD, JOHN K., JR. 09 July 2007 (has links)
No description available.
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An (R,S)-Inventory Policy for Winter Maintenance Materials for the State of OhioBrown, Nicholas Andrew 15 December 2006 (has links)
No description available.
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Estimating snow water resources from space: a passive microwave remote sensing data assimilation study in the Sierra Nevada, USALi, Dongyue 15 December 2016 (has links)
No description available.
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The Geochemistry Of Glacier Snow And Melt: The Oregon Cascades And The Taylor Valley, AntarcticaFortner, Sarah K. 10 December 2008 (has links)
No description available.
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ANALYSIS OF SURFACE MELTING AND SNOW ACCUMULATION OVER THE GREENLAND ICE SHEET FROM SPACEBORNE MICROWAVE SENSORSBhattacharya, Indrajit 09 September 2010 (has links)
No description available.
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Simulering av energianvändning och snösmältning för markvärme : Styrsystemets och geometrins påverkan / Simulating energy use and snow melting time of heated pavement : The effects of the control system and geometryMatteusson, Eric January 2022 (has links)
Ett hållbart samhälle behöver ha en klimatvänlig snöröjning. Den traditionella snöröjningen är associerad med en del problem, exempelvis bidrar saltspridning till ökad korrosion av vägar och fordon, förorening av både ytvatten och grundvatten samt ökad mobilitet av tungmetaller. Ett hållbart alternativ är hydronisk markvärme, även kallat Hydronic Asphalt Pavement, HAP. Snösmältning med ett HAP-system sker genom att en varm fluid cirkulerar i rör under ytan som ska hållas snöfri. HAP- systemets energianvändning och snösmältningskapacitet är beroende av hur de värmande rören är placerade samt vilket styrsystem som används. Rapporten syftar till att öka förståelsen för hur styrsystemet och geometrin påverkar HAP-systemets energianvändning och snösmältningstid. En numerisk 2D-modell konstrueras i COMSOL Multiphysics vilken användes för att simulera styrsystemets och geometrins påverkan på HAP-systemet. Snön förenklades som en värmesänka till vilken modellen överförde värme via ett värmeflöde. En avgränsning i rapporten var att det bortsågs från vatten på ytan för att förenkla modellen. Resultatet bekräftar att HAP-systemets styrsystem och geometri har stor påverkan på dess energianvändning och snösmältningstid. Generellt ger en hög energianvändning kortare tid med snö på ytan. Det gör att om det är önskvärt att ha ett energisnålt system behöver en avvägning mellan energianvändning och tid med snö på ytan göras. Ett intermittent styrsystem bedöms vara ett bra alternativ då det ger relativt låg energianvändning och kort tid med snö på ytan. Om det inte finns en begränsning i energianvändning finns det flera styrsystem som kan ge en snöfri yta hela året. Ytans temperatur är den bästa styrparametern att använda för att minska både energianvändning och snösmältningstid. Då värmerören placeras grundare ökar energibehovet och tiden med snö på ytan minskar. Det är möjligt att placera värmerören djupare med bibehållen snöfri tid på ytan om styrsystemet anpassas efter djupet. En viktig anpassning är att styrsystemet ger en förvärmningseffekt, exempelvis att vägen börjar värmas då vägytans temperatur understiger 1°C. En ökning av avståndet mellan värmerören, CCrör, minskar energibehovet och tiden med snö på ytan ökar. Det bedöms vara möjligt att öka CCrör till 350 mm utan att generera för stora skillnader i temperaturprofilen över ytan då rördjupet är 100 mm eller 160 mm. Det styrsystem som gynnas mest av att öka CCrör till 350 mm är ”Grundfall”, vilken värmer vägen under hela vinterhalvåret. Energianvändningen minskar då med 132 kWh/m2 (22,9%) och den längsta ihållande tiden med snö på ytan ökar från 0 h till 4 h. Beroende på vad kraven på ytan är kan det vara möjligt att ha 350 mm som CCrör för de andra styrsystemen. HAP-systemet blir resurseffektivare och billigare vid konstruktion ju större CCrör som används, vilket är önskvärt. Resultatet visar att det är en liten minskning i energianvändning och snösmältningstid då isolering är under värmerören jämfört med ingen isolering. Detbedöms därför vara omotiverat ur både energisynpunkt och snösmältningsmässigt att använda isolering under värmerören på det sätt som undersökts i detta arbete. Det är en markant skillnad i energianvändning mellan ett styrsystem som är enklare och ett som är mer komplext. Om styrsystemet ”Intermittent” används i stället för ”Grundfall” vid Hamngatan i Karlstad skulle det generera en minskad energianvändning av 4,37 GWh fjärrvärme (58,5%), vilket motsvarar 199 ton CO2 per år. Resultatet understryker vikten att ett optimalt styrsystem används. Även en liten skillnad i energianvändning kan ge stora energimässiga besparingar eftersom det ofta är stora ytor som värms med ett HAP-system. För att kunna avgöra vilket styrsystem som är bäst lämpat behöver kraven på ytan bestämmas, vilket inte görs i arbetet, utan resultaten hålls generella. / A sustainable society need to have a climate friendly snow removal system. The traditional snow removal systems generate some problems, for example increased corrosion of roads and vehicles, contamination of both surface- and ground water and increased mobility of heavy metals. A sustainable alternative is Hydronic Asphalt Pavement, HAP. Snow melting with a HAP-system is generated by circulating a warm fluid in pipes underneath the surface that is to be snow free. Both the energy usage and snow melting time is affected by how the heat pipes are placed and which control system that is used. The report aims to increase the knowledge of how both the control system and geometry of the heating pipes affect the energy use and snow melting time of a HAP-system. A numerical 2D-model was constructed in COMSOL Multiphysics which was used to simulate how the control system and geometry of the heating pipes effects the HAP-system. The snow was simplified to a heat sink, to which the model could transfer heat through a convective heat flux. A demarcation of the study is that water on the surface is ignored to simplify the model. The results confirms that both the control system and geometry of the heat pipes greatly affects the energy usage and snow melting time. In general, a large energy usage generates a shorter total time with snow on the surface. It is therefore needed to do a balancing between energy usage and the total time with snow on the surface if the energy usage is to be restricted. An intermittent control system is considered to be a good alternative as it gives a relative low energy usage and short time with snow on the surface. If there is no limitation on the energy use, there is several control systems that gives a snow free surface throughout the year. The surface temperature is the best parameter for the control system as it minimizes both the energy usage and snow melting time. When the heating pipes is placed shallower the energy usage is increased and the time with snow on the surface decreases. It is possible to place the heating pipes at a greater depth and still have the same functionality of the HAP-system if the control system is adjusted accordingly. One important adjustment for the control system is preheating, for example that the heating is turned on when the air temperature is less than 1°C. An increase of CCrör decrease the energy usage and increase the time with snow on the surface. It is possible to increase CCrör to 350 mm and still have a smooth temperature profile if the heating pipes is placed 100 mm or 160 mm beneath the road surface. The control system that gains the most out of an increase in !!!ö! to 350 mm is “Grundfall”, which reduce its energy usage with 132 kWh/m2 (22,9%) and the longest time with snow on the surface is increased from 0 h to 4 h. Depending on which demands the surface is to meet, it is possible to have 350 mm as CCrör for the other control systems. An increase in CCrör makes the HAP-system more resource efficient and cheaper to build, which is desirable. The results show a small decrease in energy usage and snow melting time when isolation is underneath the heating pipes compared to without isolation. It is therefore deemed to be unmotivated to use isolation as it is used in this paper, in both energy use- and snow melting time-perspective. There is a significant difference in energy use between a simple and more complex control system. If the control system “Intermittent” is used instead of “Grundfall” at Hamngatan in Karlstad the energy usage would decrease with 4,37 GWh heat (58,5%) and 199 ton of CO2. The result underlines the importance of an optimal control system for a HAP-system. Even a small change in energy consumption can generate large energy savings due to the scale of the surfaces that is heated with HAP-systems. To be able to decide which control system that is the best suited, the demand on the surface needs to be set. The demands are not set in this paper in order to keep the results general.
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Starting with Snow White: Disney's Folkloric Impact and the Transformation of the American Fairy TaleDiLullo Gehling, Dana M. January 2018 (has links)
Since the late 1960s and early 1970s, critical scholarship concerning the fairy tale genre has done much to address the social, historical, cultural, and national motivations behind transformations of the fairy tale from a European starting point. However, the fairy tale’s development in the United States, including both its media-based adaptations and literary extensions, has been given limited attention. While the significance of Walt Disney’s animated films to the American fairy tale tradition has been addressed (by literary and film scholars alike), an interdisciplinary study drawing together Disney’s European and early twentieth century precursors (from literature, stage, and film); his own influential, modern debut; respondent literary and animated work of his immediate successors; and postmodern and twenty-first century adaptations has not been done. By examining the trajectory of a single tale, Snow White (or for Disney, Snow White and the Seven Dwarfs), this dissertation aims to acknowledge the scholarly attention given to Disney’s animated films, while further examining attributes which I suggest have enabled Disney to have a “folkloric impact” on the fairy tale genre in the United States. Disney’s work stands upon the bedrock of not only European but American Snow White variations and makes these “new” through an innovative deployment and unification of word or language, sound, and image, unimagined prior to the debut of Snow White and the Seven Dwarfs (1937). The effects of Disney’s influence, as a master storyteller, on both the fairy tale genre and commercial market were so profound that this particular version of the tale refuses to be forgotten, its shadow haunting successors who aimed to counter or redefine its understanding of fairy tale in light of shifting American values and culture. Therefore, even as the fairy tale is frequently understood to have moved beyond its folkloric “origins” (I use this term loosely, as the origins of fairy tale are surrounded by controversy), using the critical framework of folklorists Steven Swann Jones and Linda Dégh, as well as filmic folklorists, Sharon R. Sherman and Juwen Zhang, I explore how Disney’s patchwork of tradition, new technology, and media generated an easily recognizable and communicable tale, one that would be recalled, repeated, and reformed through adaptation by generations of audiences. These subsequent storytellers, in turn, extend American fairy tale tradition and lore still further. / English
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Analysis of Pressurized Arch-ShellsGoh, Julian Kok Seng 11 April 1998 (has links)
A pressurized arch-shell structural component made of flexible material is considered. The component is inflated with high internal pressure. The behavior of similar types of structures, such as a pair of leaning pressurized arches and pressurized arch-supported membrane shelters, has been investigated in the past. More recently, several types of pressurized structures have been incorporated as part of the framework for a variety of structural systems. Particularly, the U.S. Army has been investigating the use of large lightweight and transportable pressurized arch-shell structures to be used as maintenance shelters for vehicles, helicopters, and airplanes.
The formulated equations using thin shell theory are applied to a pressurized arch-shell component. A numerical investigation based on the Rayleigh-Ritz method is utilized to determine the behavior of arch-shells under various types of loading. The types of loading include a uniformly distributed vertical load representing snow, a wind load, and a horizontal side load distributed along the arc length. Deflections, stress resultants, and moments at various locations are computed for two types of shapes: circular and non-circular arch-shells. / Master of Science
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A strategic typology for UK small and medium sized enterprises. An investigation of influential factors and the development of a predictive typologyKendrick, Sean January 2012 (has links)
The success of small and medium enterprises (SMEs) is critical to Europe’s
economic health, however, our understanding of SME strategic behaviour is
predominantly based on large enterprise theory. This study uses the Miles and
Snow (1978) typology to examine the strategic behaviour of 150 UK SMEs. It
also investigates whether strategy type, environment adaptation and
organisational performance can be predicted by several contingency factors:
organisation size, age, industry type, and management style.
The findings confirm that the typology is not well suited for categorising SMEs;
organisations that rarely develop through all three domains of the adaptive cycle
to be sufficiently eligible for categorisation by one of the four pure archetypes.
However, similar patterns of strategic behaviour were observed for certain
dimensions, largely independent of the industry type or size of the SME,
suggesting that an optimal configuration of mixed strategies may exist.
Furthermore, Reactors, or those with mixed strategies, were found to perform
similarly as Analysers and better than Defenders.
The study also found that by fitting nominal logistic regression models to
organisation age and size data, it was possible to predict strategic behaviour
and environment adaptation, and to a lesser degree, financial performance.
Surprisingly, the industry type and management style data were observed to
exert minimal influence on the outcome variables.
Finally, this research provides important insight relating to the validity concerns
of the Miles and Snow typology and categorisation method employed, and
demonstrates how these can be avoided.
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