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"One to the Head, Two to the Heart": The Failure of Psychological Warfare Doctrine and Understanding in The Vietnam WarRable, Kyle K. 11 May 2021 (has links)
No description available.
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Ice Cold Urban Planning : A Literature Review on Challenges and Strategies in Designing Sustainable Winter Cities / Iskall stadsplanering : En litteraturöversikt om utmaningar och strategier vid utformning av hållbara vinterstäderHuerta, Carlos, Axelsson, Catrin January 2023 (has links)
Designing winter cities after the conditions of the winter weather entails unique challenges that require urban planning that is adapted to the specific conditions. One challenge is enabling transportation and accessibility despite heavy snowfall and slippery road surfaces. Understanding these challenges that may arise during the planning and designing of winter cities is crucial for achieving sustainable urban development. As the population increases and climate changes become increasingly unpredictable, winter cities must be planned to optimize land use and create comfortable living spaces. This is essential for preserving important values of nature and cultural values, as well as creating livable environments regardless of the climate. The purpose of this study is to compile and map the challenges of designing winter cities and identify strategies and solutions for sustainable urban planning in cold climates. Through a literature review as a method, a thematization of research and studies in the subject area was compiled and conducted. The thematization resulted in three main themes: Urban design and layout, Operations and maintenance, and Transportation and street space. Thus, the results consist of these themes and associated subheading for each theme. The study shows that winter cities must actively consider multiple aspects, including the need for microclimates, efficient snow clearing, prioritization of soft mobility, and innovative alternatives such as winter trails. Weighing different interests against and considering both practical and aesthetic aspects is crucial in the planning process. The study also highlights the importance of managing conflicts between different modes of transportation and the potential role of winter trails in promoting sustainable mobility. The study suggests exploring alternative solutions for winter trails and how snow management can be made more efficient through further research. This way, urban planners can create sustainable and inviting winter cities for both residents and visitors / Utformningen av vinterstäder efter vinterförhållanden medför unika utmaningar som kräver en stadsplanering som är väl anpassad till de specifika förutsättningarna. En utmaning är att möjliggöra transport och tillgänglighet trots stora snömängder och halt underlag. Förståelsen kring utmaningar som kan uppkomma vid planering och utformning av vinterstäder är avgörande för att uppnå en hållbar stadsutveckling. I takt med att befolkningen ökar och klimatförändringar blir alltmer oförutsägbara måste vinterstäder planeras för effektivisering av markanvändning och behaglig livsmiljö. Detta är viktigt för att bevara värdefulla natur-och kulturvärden, men även för att skapa miljöer som går att bo på oavsett klimat. Syftet med denna studie är att sammanställa och kartlägga utmaningarna med att utforma vinterstäder och identifiera möjliga strategier och lösningar för hållbar stadsplanering i kallt klimat. Genom en litteraturöversikt som metod sammanställdes och utfördes en tematisering av forskning och studier inom ämnesområdet. Tematiseringen mynnade ut i tre huvudteman; Urban design och utformning, Drift och underhåll och Transport och gaturum. Således utgörs resultatet av dessa teman samt tillhörande underrubriker för respektive tema. Studien visar att vinterstäder aktivt måste beakta flera aspekter, bland annat behovet av mikroklimat, effektiv snöröjning, prioritering av mjuk mobilitet samt nytänkande alternativ såsom vinterleder. Att väga olika intressen mot varandra och samtidigt beakta både praktiska och estetiska aspekter är avgörande i planeringsprocessen. Studien framhäver också vikten av att hantera konflikter mellan olika transportmedel samt rollen som vinterleder skulle kunna spela för att främja hållbar mobilitet. Studien föreslår att man utforskar alternativa lösningar för vinterleder samt hur snöhanteringen skulle kunna effektiviseras, detta genom vidare forskning. På så sätt kan stadsplanerare skapa hållbara och inbjudande vinterstäder för både boende och besökare.
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Разработка принципов построения малогабаритного снегоболотохода с дистанционным управлением : магистерская диссертация / Development of design principles for small-size remotely controlled snow-and-swamp mobilesШонохова, Н. А., Shonokhova, N. A. January 2018 (has links)
Выпускная квалификационная работы выполнена на тему «Разработка принципов построения малогабаритного снегоболотохода с дистанционным управлением».
Расчетно-пояснительная записка содержит 198 листов, 90 рисунков, 16 таблиц, 11 источников, 42 приложения.
Объектом разработки является малогабаритный снегоболотоход с дистанционным управлением, предназначенный для инженерно-изыскательских работ.
Цель работы – разработка принципов построения малогабаритного снегоболотохода с дистанционным управлением, в том числе разработка новых узлов, выбор из ранее представленных, модернизация и реконструкция элементов, разработанных для других машин.
В результате проведенной работы спроектированы 3 шнековых движителя, 4 подвески, 2 системы управления, также рассмотрены блоки задания скорости, кольцевые распределители импульсов и преобразователи «Код-напряжение».
В проекте также рассмотрены вопросы безопасности труда, радиационная безопасность и природопользование и охрана окружающей среды.
В разделе технико-экономических показателей приведены единовременные, текущие и приведенные затраты. / The goal of the research was to justify the selection of various structural elements and control systems on the basis of both design parameters and the analysis of assigned tasks. Thus, a number of existing designs of machines, propellers and suspensions were considered in the course of the study, all of which could be used for different purposes: for example, it is more rational to utilize motor-in-wheel propellers to glide over the water, since those are most lightweight and waterproof of all, and to choose a spring suspension – since it contains the minimal number of elements which could fail in the water medium.
As to the systems of control, the selection of their control blocks is made on the criteria of reliability, since it is necessary to ensure no-failure operation of the system as a whole.
As a result of the work, 3 screw propellers, 4 suspensions, 2 control systems were designed, and a few speed assignment blocks, circular distributors of impulses and number-to-voltage converters were considered.
The project also analyses the problems of work safety, radiation safety, conservation and environment control.
The section on project feasibility cites nonrecurring, current and reduced costs.
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Glide Quality in Cross-Country Skiing : The Topographical and Frictional Impact of the Stone GrindJohansson, Martin January 2022 (has links)
The Swedish Winter Olympic team is one of the strongest Olympic teams in theworld, and the majority of the team’s success comes from ski-related sports. So howcan the Swedish team remain, and maybe even accelerate, its competitive advantage? The answer is science. In order to narrow down the broad field that is equipment development, this thesishad the purpose to examine the stone grind’s impact on friction between the ski andthe snow. To achieve this purpose, the project was designed to answer these threequestions: • How does the ski base impact the friction between the ski and the snow? • How do the stone grind’s parameters impact the ski base? • How do the stone grind’s parameters impact the friction between the ski andthe snow? To answer these questions, a total of three pilot tests were done before the finalfull-scale experiment. The method to strategically test the parameters of the stonegrind was to use a full two-level factorial design, with a total of three stone grindparameters being investigated. Those parameters were: Cutting Depth, Line Density,and Wheel Pressure. The skis were tested in Arctic Fall’s indoor facilities where theskis were tested with a winch set-up to get the skis up to a desired speed, and thedata collected from the test were speed data from each of the skis. This speed datawould then be used to calculate the coefficient of friction acting between the ski andthe snow. To understand the stone grinds parameters on the ski base, the ski basesurfaces were measured after the skis were grounded, to build a regression modelconsisting of stone grind parameters as independent variables, and surface parametersbeing the dependent variables. A model was created suggesting that in the conditions the tests were executed, thesurface parameters Sa should be minimized and Sm should be maximized to achievea minimized coefficient of friction. A more generalisable model to impact the surfaceparameters Sa and Sm was also generated. It suggests that to impact Sa and Sm, itis the stone grind parameter Cutting Depth and Line Density that should be adjustedto achieve a desirable ski base structure.
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Moving Up the Social Ladder: An Analysis of the Role of Temptation in Shaping Characters in Select Fairy Tales Employing Marxist and Psychological LensesIacovetta, Anna C. 27 June 2017 (has links)
No description available.
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Corrosion inhibition mechanism of a surfactant admixture on carbon steel alloy ASTM A36 [UNS K02600] coated with a high performance UV-cured coatingRodriguez, Alvaro A. 09 June 2016 (has links)
No description available.
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Developing Strategies For Year-Round Spray Irrigation of Wastewater Effluent in OhioGunn, Kpoti Mawutodzi 15 January 2010 (has links)
No description available.
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Tvorba odtoku a jeho dynamika v pramenné oblasti Otavy / Streamflow generation process and its dynamics in the Otava river headwatersKocum, Jan January 2012 (has links)
In context of catastrophic floods and extreme droughts in recent years there is an urgent need of solving of issues dealing with protection against hydrological extremes, not using just classical engineering methods but also untraditional practices. There is a new protection strategy focusing on gradual increase of river catchment retention capacity including its headwater regions. All of the issues related to various possibilities and measures leading to river headstream areas retention capacity increase should be discussed by experts in various fields taking into account objectives and priorities of a supra-regional, regional and local significance. Natural runoff process is affected by man already by its birth, thus in headwaters where numerous procedures related to runoff retardation and water retention increase in headstream areas could be realized. Suitable conditions for the research realization at present is related to the Otava River headwaters (sw. Czechia) representing the core zone of a number of extreme runoff events and with high heterogeneity in the terms of physical-geographic and socio-economic aspects. To understand and clarify the runoff generation process and the effect of various physical-geographic factors on its dynamics, the detailed analyses of runoff regime in chosen...
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Thermal stability of sub-Arctic highways : impacts of heat advection triggered by mobile water flow under an embankmentChen, Lin 09 1900 (has links)
Les infrastructures de transport est essentielle au maintien et à l'expansion des activités sociales et économiques dans les régions circumpolaires. À mesure que le climat se réchauffe, la dégradation du pergélisol sous les remblais a entraîné de graves dommages structuraux à la route, entraînant une augmentation importante des coûts d'entretien et une réduction de la durée de vie des infrastructures. Pendant ce temps, l'advection de chaleur déclenchée par les écoulements d’eau souterrains peut altérer le bilan énergétique du remblai et du pergélisol sous-jacent et modifier le régime thermique des remblais routiers. Cependant, peu de recherches ont été effectuées pour comprendre la synergie entre les processus thermiques de surface et souterrains des remblais routiers des régions froides. L'objectif de cette recherche était de comprendre les interactions thermiques entre l'atmosphère, le remblai routier, les écoulements d’eau et le pergélisol dans le contexte du changement climatique. Cette base, de connaissances est nécessaire pour la conception technique, l'entretien des routes et l'évaluation de la vulnérabilité des infrastructures.
Les travaux de recherche ont permis de développer de nouvelles méthodes d'analyse thermique pour caractériser et identifier le rôle de l'advection thermique sur le changement de température d'un remblai routier expérimental au Yukon (Canada) en termes d’intensité, de vitesse et de profondeur de l'impact thermique. Les résultats montrent que l'augmentation de la température due aux flux de chaleur advectifs déclenchés par l’écoulement d'eau peut être jusqu'à deux ordres de grandeur plus rapide qu'en raison du seul réchauffement atmosphérique.
La recherche a ensuite présenté un bilan énergétique de surface pour quantifier la quantité d'énergie entrant dans le centre et la pente du remblai avec des épaisseurs et des propriétés de neige variables. Le tout a été appuyé par des observations géothermique de plusieurs années et une grande quantité de données météorologiques. Les résultats illustrent que le bilan énergétique de surface est principalement contrôlé par le rayonnement net et moins par le flux de chaleur sensible. Le flux de chaleur transmis à la pente du remblai diminue de façon exponentielle avec l'augmentation de l'épaisseur de la neige et diminue de façon linéaire avec l’installation du couvert de neige et la longueur de la période d’enneigement.
De plus, un modèle de bilan énergétique de surface et un modèle cryohydrologique entièrement couplé ont été développés pour étudier l'impact thermique de l'advection de chaleur associée à l'écoulement de l'eau souterraine sur le dégel du pergélisol et le développement de taliks (c.-à-d. zone perpétuellement non gelée dans les zones de pergélisol). Le modèle couplé a réussi à reproduire la tendance à la hausse du plafond du pergélisol (erreur absolue moyenne <0,2 m) au cours de la période 1997-2018. Les résultats montrent que l'advection de chaleur a fourni une source d'énergie supplémentaire pour accélérer le dégel du pergélisol et a doublé le taux d’augmentation de l’épaisseur de la couche active 0,1 m·a-1 à 0,19 m·a-1, par rapport au scénario où aucun écoulement d'eau ne se produit. Le talik s'est initialement formé et développé en fonction du temps sous l’effet combiné des écoulement d’eau, de l'isolation de la neige, de la construction de la route et du réchauffement climatique. Le débit d'eau souterraine a relié des corps isolés de talik et a amené le remblai de la route dans un état thermique irréversible, en raison de la rétroaction de l'eau liquide (effet de chaleur latente) piégée dans le talik.
Ces résultats montrent l'importance de l'advection de chaleur induite par l'écoulement d'eau sur le régime thermique de la sous-couche (c.-à-d. la couche de matériau de remblai) et du sous-sol (c.-à-d. le matériau natif sous un remblai) du remblai lorsque le remblai routier intercepte le drainage local. De plus, les résultats obtenus soulignent la nécessité de coupler les processus thermiques de surface et souterrains dans le but d'évaluer la stabilité thermique des routes subarctiques. / Transportation infrastructure is crucial to maintaining and expanding the social and economic activities in circumpolar regions. As the climate warms, degradation of the permafrost causes severe structural damages to the road embankment, leading to large increases in maintenance costs and reductions in its lifespan. Meanwhile, heat advection triggered by mobile water flow can alter energy balance of the embankment and underlying permafrost and modify the thermal regime of road embankments. However, little research has been done to understand the synergy between surface and subsurface thermal processes of cold region road embankments. The overall goal of this research was to elucidate thermal interactions between the atmosphere, the road embankment, mobile water flow, and permafrost within the context of climate change. This knowledge is needed for engineered design, road maintenance, and infrastructure vulnerability assessment.
The research first used new thermal analysis to characterize and identify the role of heat advection on temperature change of an experimental road embankment, Yukon, Canada in terms of magnitude, rate and thermal impact depth. It shows that soil temperature increase due to advective heat fluxes triggered by mobile water flow can be up to two orders of magnitude faster than due to atmospheric warming only.
The research then presented a novel surface energy balance to quantify the amount of ground heat flux entering the embankment center and slope with varying snow depth and properties, supported by multi-year thermal and meteorological observations. My results illustrate that the surface energy budget is mainly controlled by net radiation, and less by the sensible heat flux. The ground heat flux released at embankment slope exponentially decreased with the increase of snow depth, and was linearly reduced with earlier snow cover and longer snow-covered period.
A fully integrated surface energy balance and cryohydrogeological model was implemented to investigate the thermal impact of heat advection associated with subsurface water flow on permafrost thaw and talik (i.e., perennially unfrozen zone in permafrost areas) development. The integrated model successfully reproduced the observed increasing trend of the active layer depth (mean absolute error < 0.2 m) over the 1997-2018 period. The results show that heat advection provided an additional energy source to expedite permafrost thaw, doubling the increasing rate of permafrost table depth from 0.1 m·a-1 to 0.19 m·a-1, compared with the scenario where no water flow occurs. Talik formation and development occurred over time under the combined effect of subsurface water flow, snow insulation, road construction and climate warming. Subsurface water flow connected isolated talik bodies and triggered an irreversible thermal state for the road embankment, due to a local feedback mechanism (latent heat effect) of trapped, unfrozen water in talik.
These findings elucidate the importance of heat advection induced by mobile water flow on the thermal regime of embankment subbase (i.e., a layer of fill material) and subgrade (i.e., the native material under an embankment) when the road embankment intercepts the local drainage. Furthermore, the obtained results emphasize the need to couple surface and subsurface thermal processes to evaluate the thermal stability of sub-Arctic roads.
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Climate change impacts on mountain snowpack presented in a knowledge to action frameworkSproles, Eric Allan 16 February 2012 (has links)
Throughout many of the world’s mountain ranges snowpack accumulates during the winter and into the spring, providing a natural reservoir for water. As this reservoir melts, it fills streams and recharges groundwater for over 1 billion people globally. Despite its importance to water resources, our understanding of the storage capacity of mountain snowpack is incomplete. This partial knowledge limits our abilities to assess the impact that projected climate conditions will have on mountain snowpack and water resources.
While understanding the effect of projected climate on mountain snowpack is a global question, it can be best understood at the basin scale. It is at this level that decision makers and water resource managers base their decisions and require a clarified understanding of basin's mountain snowpack. The McKenzie River Basin located in the central-western Cascades of Oregon exhibits characteristics typical of many mountain river systems globally and in the Pacific Northwestern United States. Here snowmelt provides critical water supply for hydropower, agriculture, ecosystems, recreation, and municipalities. While there is a surplus of water in winter, the summer months see flows reach a minimum and the same groups have to compete for a limited supply.
Throughout the Pacific Northwestern United States, current analyses and those of projected future climate change impacts show rising temperatures, diminished snowpacks, and declining summertime streamflow. The impacts of climate change on water resources presents new challenges and requires fresh approaches to understanding problems that are only beginning to be recognized. Climate change also presents challenges to decision makers who need new kinds of climate and water information, and will need the scientific research community to help provide improved means of knowledge transfer.
This dissertation quantified the basin-wide distribution of snowpack across multiple decades in present and in projected climate conditions, describing a 56% decrease in mountain snowpack with regional projected temperature increases. These results were used to develop a probabilistic understanding of snowpack in projected climates. This section described a significant shift in statistical relations of snowpack. One that would be statistically likely to accumulate every 3 out of 4 years would accumulate in 1 out of 20 years. Finally this research identifies methods to improved knowledge transfer from the research community to water resource professionals. Implementation of these recommendations would enable a more effective means of dissemination to stakeholders and policy makers.
While this research focused only on the McKenzie River Basin, it has regional applications. Processes affecting snowpack in the McKenzie River Basin are similar to those in many other maritime, forested Pacific Northwest watersheds. The framework of this research could also be applied to regions outside of the Pacific Northwestern United States to gain a similar level of understanding of climate impacts on mountain snowpack. / Graduation date: 2012
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