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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.
1

Mobile robot navigation in hilly terrains

Tennety, Srinivas 23 September 2011 (has links)
No description available.
2

Glacial dynamics and till genesis in hilly terrain : A study in the Tallträsk area, central-northern Sweden

Ivarsson, Hans January 2007 (has links)
<p>This study deals with the influence of topography on glacial dynamics and the genesis of till in an area of moder-ate bedrock relief. An area 25 km west of Lycksele, northern Sweden, was investigated using geomorphological and sedimentological methods. The bedrock is dominated by coarse-grained granites and the topography, ranging in altitude between 310 and 490 m. a.s.l., is characterized by relatively wide, free-lying hills.</p><p>The erosional and depositional features provide evidence of several glacial events, with regional ice flows from approximately the same direction (NW-NNW). The gravel fraction of the till is dominated by material transported more than 10 km. However, the total glacial erosion has been modest, as indicated by the frequent occurrence of residual pre-glacial weathering features. There is no evidence of warm-based conditions during the period when the ice divide of the Late Weichselian ice sheet was situated E-SE of the study area. The major mor-phological impact is most likely by pre-Late Weichselian ice sheets.</p><p>The general stratigraphy at the valley floors is a complex sequence of heterogeneous till and beds of sorted sediments with some evidence of glacial deformation covered by an up to 2.5-m-thick, texturally homogeneous till layer with distinct fissility structure and clast fabric orientation. The lower unit is interpreted as pre-Late Weichselian marginal deposits, and the upper till as mainly formed during rigid-bed conditions, i.e. by lodgement, during the last deglaciation. The role of pervasive deformation and melt-out in the formation of the upper till are discussed. Inferred mainly from till fabrics it is evident that the ice flow was strongly topographically controlled within a relatively wide marginal zone of the retreating ice.</p><p>At the summits of the hills there are only signs of very weak glacial abrasive and depositional activity, sug-gesting frozen based conditions over the summits until a very late stage of the deglaciation. The very thin till at the summits, which also lay as a drape over the thick lee-side deposits, consists of a mixture of relatively fine-grained, distantly derived debris and of local bedrock fragments entrained during a very late phase of plucking.</p><p>On the stoss- and lateral slopes of the hills the till is thin and discontinuous. The irregular bedrock surface in these areas created a “mosaic” of small-scale subglacial depositional environments, which were superimposed on the changes in the conditions for deposition along the hillslope. This till is comparatively coarse-grained, which is interpreted as an effect of syn-depositional winnowing of fines, and locally also because of the incorporation of local bedrock material largely from pre-glacially weathered zones.</p><p>On the lee-sides of the hills the deposits are considerably thicker than on slopes facing other directions. They are characterized by highly variable texture and structure, suggesting a depositional environment characterized by large temporal and spatial variations in meltwater activity and stress/strain conditions. The lee-side tills are inter-preted as mainly pre-Late Weichselian in age.</p><p>The overall conclusion is that the local topography strongly controlled the basal ice flow and produced a com-plex pattern of thermal variations within a relatively wide marginal zone of the ice sheet during the last deglacia-tion. The study supports the view that there are complete transitions between the different genetical types of sub-glacial tills, although the role of deformation by pervasive shearing is uncertain in this type of coarse-grained till.</p>
3

Glacial dynamics and till genesis in hilly terrain : A study in the Tallträsk area, central-northern Sweden

Ivarsson, Hans January 2007 (has links)
This study deals with the influence of topography on glacial dynamics and the genesis of till in an area of moder-ate bedrock relief. An area 25 km west of Lycksele, northern Sweden, was investigated using geomorphological and sedimentological methods. The bedrock is dominated by coarse-grained granites and the topography, ranging in altitude between 310 and 490 m. a.s.l., is characterized by relatively wide, free-lying hills. The erosional and depositional features provide evidence of several glacial events, with regional ice flows from approximately the same direction (NW-NNW). The gravel fraction of the till is dominated by material transported more than 10 km. However, the total glacial erosion has been modest, as indicated by the frequent occurrence of residual pre-glacial weathering features. There is no evidence of warm-based conditions during the period when the ice divide of the Late Weichselian ice sheet was situated E-SE of the study area. The major mor-phological impact is most likely by pre-Late Weichselian ice sheets. The general stratigraphy at the valley floors is a complex sequence of heterogeneous till and beds of sorted sediments with some evidence of glacial deformation covered by an up to 2.5-m-thick, texturally homogeneous till layer with distinct fissility structure and clast fabric orientation. The lower unit is interpreted as pre-Late Weichselian marginal deposits, and the upper till as mainly formed during rigid-bed conditions, i.e. by lodgement, during the last deglaciation. The role of pervasive deformation and melt-out in the formation of the upper till are discussed. Inferred mainly from till fabrics it is evident that the ice flow was strongly topographically controlled within a relatively wide marginal zone of the retreating ice. At the summits of the hills there are only signs of very weak glacial abrasive and depositional activity, sug-gesting frozen based conditions over the summits until a very late stage of the deglaciation. The very thin till at the summits, which also lay as a drape over the thick lee-side deposits, consists of a mixture of relatively fine-grained, distantly derived debris and of local bedrock fragments entrained during a very late phase of plucking. On the stoss- and lateral slopes of the hills the till is thin and discontinuous. The irregular bedrock surface in these areas created a “mosaic” of small-scale subglacial depositional environments, which were superimposed on the changes in the conditions for deposition along the hillslope. This till is comparatively coarse-grained, which is interpreted as an effect of syn-depositional winnowing of fines, and locally also because of the incorporation of local bedrock material largely from pre-glacially weathered zones. On the lee-sides of the hills the deposits are considerably thicker than on slopes facing other directions. They are characterized by highly variable texture and structure, suggesting a depositional environment characterized by large temporal and spatial variations in meltwater activity and stress/strain conditions. The lee-side tills are inter-preted as mainly pre-Late Weichselian in age. The overall conclusion is that the local topography strongly controlled the basal ice flow and produced a com-plex pattern of thermal variations within a relatively wide marginal zone of the ice sheet during the last deglacia-tion. The study supports the view that there are complete transitions between the different genetical types of sub-glacial tills, although the role of deformation by pervasive shearing is uncertain in this type of coarse-grained till.
4

Localized, flow dependent, sweet corrosion at regions of drastic changes in elevations: Hilly terrain and river crossings

Laws, Jason G. January 2000 (has links)
No description available.
5

Kontinentální zalednění severovýchodní části Frýdlantského výběžku / Continental glaciation of the northeastern part of the Frýdlant Spur

Lehejček, Jiří January 2012 (has links)
North-eastern part of Frýdlantský Spur is situated at the northern foothills of the Jizera Mountains. It represents an area, which was at least twice covered by North-European ice sheet during the Middle Pleistocene. At the same time, it is the region whose hills have the summits around the expected altitudinal limit of the maximum ice sheet extent. Therefore, it is a suitable area to study glacial trimline altitude. Schmidt hammer testing was applied to determine different state of rock surface weathering. Obtained R-values were taken as the most relevant data for glacial trimline determination. Nevertheless, other approaches (GIS analysis, outcrops, block fields and erratics mapping) were also incorporated. Interpretation of these approaches gave the altitudinal limit of ice sheets in the north-eastern part of the Frýdlantský Spur at 500 m a. s. l. ± 20 m.
6

Utvärdering av dataprogram för vindresursberäkningar : En jämförelse av vindresursberäkningar i kuperad skogsterräng med programmet WAsP (linjär modellering) och CFD-programmet WindSim / An evaluation of wind energy software : A comparison of wind resource calculations made with the software WAsP (linear model) and the CFD software WindSim over a hilly forested area

Johansson, Eric January 2013 (has links)
Vindkraft för generering av el har under de senaste åren vuxit kraftigt i Sverige och utbyggnaden väntas fortsätta. Ett viktigt steg när nya vindkraftsparker skall byggas är att göra en vindanalys för det aktuella området. Vindanalysen är ett viktigt underlag för att avgöra om en investering i vindkraftverk kommer vara ekonomiskt lönsamt på den aktuella platsen.      Som underlag till vindanalysen sätts vanligen mätutrustning upp i området och vindförhållandena på platsen mäts upp. Att installera och underhålla mätmaster är kostsamt och därför mäts vindarna på ett begränsat antal platser i det intressanta området. Sedan används olika beräkningsprogram för att extrapolera de uppmätta vindresurserna till positioner där mätningar saknas. För närvarande används programmet WAsP som standard av många vindkraftsprojektörer. WAsP:s beräkningsmodell är relativt enkel och tar till exempel inte hänsyn till turbulens som uppkommer då terrängen är kuperad. Som ett alternativ till WAsP har olika CFD-program introducerats på marknaden under senare år. Dessa programs modeller är mer avancerade och de kräver därför längre beräkningstid jämfört med WAsP, men förhoppningen är att de skall ge mer tillförlitliga modelleringsresultat. I denna studie har vindmodelleringar i det linjära modelleringsprogrammet WAsP jämförts med modelleringar i CFD-programmet WindSim. Syftet har varit att undersöka om WAsP ger tillförlitliga modelleringsresultat i svenskt kuperat skogslandskap och om WindSims CFD-beräkningar kan ge en ökad noggrannhet i jämförelse. Prestandan hos respektive program har utvärderats genom att jämföra extrapolerade medelvindar med faktiska mätningar. Vindmätningar har funnits att tillgå från en period av 12 månader från två mätmaster med givare på 60, 80 och 100 meters höjd. Avståndet mellan masterna är cirka 10 kilometer.            Resultaten från studien tyder på att WindSim kan ge en något ökad noggrannhet jämfört med WAsP, men resultaten visar samtidigt att en CFD-modellering inte med automatik ger mer tillförlitliga modelleringsresultat. Studien har visat att resultatet från WindSim är starkt beroende av hur modellen sätts upp och det kan därför vara enklare att göra fel i WindSim jämfört med WAsP. Det blev också tydligt att en modell där den simulerad vindskjuvning (variation av vindhastigheten i höjdled) stämde bra överens med den uppmätta inte behöver betyda att WindSim-modellen gör bra extrapolationer av vindförhållandena från den ena masten till den andra. Vidare visade sig WAsP missbedöma effekter från topografin något och om vindmätningar görs på utmärkande höjder är det sannolikt att WAsP överskattar vindförhållandena i de lågt belägna delarna av terrängen. I WindSim undersöktes två olika modelluppsättningar, en med WindSims skogsmodul där skogen simuleras som 3D objekt och en modell där skogen hanteras med på samma sätt som i WAsP med råhetslängd och nollplansförskjutning. När skogsmodulen användes var det inte möjligt att erhålla en modellerad vindskjuvning som stämde överens med den uppmätta i en neutral atmosfär, vilket är WindSims standardinställning för atmosfärsstabiliteten. I en neutral atmosfär med skogsmodulen överskattades vindhastigheten på låga höjder. Om atmosfären simulerades som stabil i medeltal var det möjligt att få den simulerad vindskjuvning att stämma överens med den uppmätta, men extrapolationerna i horisontalled blev inte bra med denna modell. Om atmosfären skall simuleras som stabil i WindSim tyder resultaten från studien på att vindmätningarna måste delas in efter rådande atmosfärstabilitet för den aktuella tidpunkten för mätningen. Det fungerade inte tillfredställande att använda alla vindmätningar i samma modell och försöka hitta ett passande medelvärde för stabiliteten.  Om vindmätningarna skall delas upp efter rådande stabilitet kommer varje stabilitet kräva en egen modellering vilket betyder att beräkningstiden kommer öka markant. Att simulera skogen i WindSim med en råhetslängd och en nollplansförskjutning visade sig fungera bra. En modellerad vindskjuvning som stämde bra överens med den uppmätta kunde erhållas i en neutral atmosfär och denna modell presterade sammantaget bäst av alla undersökta modeller i den här studien. Det studerade området består övervägande av skog och vindmätningarna som använts är utförda inom skogsområdet. WindSim skogsmodul kan tänkas vara mer användbar och viktig om skog förekommer i begränsade partier och då tänkta vindturbiner inte placeras direkt inom skogsområdet. En förhoppning på CFD-program är att vindmätningar utförda på låg höjd skall kunna användas för att förutse vinden på högre höjder med större noggrannhet jämfört med WAsP. Resultat från den här studien visar dock att det kan vara svårt att uppnå en bra modellerad vindskjuvning i WindSim. Även i WindSim är således viktigt att ha vindmätningar från flera olika höjder för att kunna verifiera modellen mot innan programmet kan förväntas förutse vinden på högre höjder korrekt.    Sammanfattningsvis förefaller en bra inställd WindSim-modell kunna ge en något ökad noggrannhet av extrapolerade vindförhållanden jämfört med WAsP, men om extrapolationer skall göras mellan liknade områden i terrängen, till exempel från en kulle till en annan kulle, är det tveksamt om den lilla ökade noggrannheten ger skäl för den ökade beräkningstiden i WindSim. / An evaluation of wind energy software: a comparison of wind resource calculations made with the software WAsP (linear model) and the CFD software WindSim over a hilly forested area.  Results produced from the wind modeling linear program WAsP were compared with modeling results produced by the CFD program WindSim. The aim was to investigate whether WAsP achieves accurate calculation results over a hilly forested area in Sweden, and if the CFD modeling in WindSim provides more accurate results than WAsP. The performance of each program was evaluated by comparing extrapolated average wind speed data to actual measurements. The study shows that WindSim may achieve an increased accuracy of extrapolated wind conditions compared to WAsP, as well as indicates that a CFD calculation does not automatically provide more reliable extrapolations than linear modeling in WAsP. The accuracy of the WindSim extrapolations was highly dependent on how the model was set up, and hence it may be easier to make errors with WindSim compared to WAsP. A model in WindSim with accurate simulated wind shear did not necessarily mean that the model made good extrapolations of wind conditions horizontally. Furthermore, WAsP was shown to slightly misjudge orographic effects, and when wind measurements are made over hilltops, WAsP most likely overestimates the average wind speed in the lower parts of the terrain.     When a good model was established, WindSim provided slightly more accurate results than WAsP, but if extrapolations are to be made between similar areas in the terrain, for example from one hill to another hill, it is doubtful that the small increase in accuracy gives enough reason for the increased time in calculation required by WindSim.
7

Penzion / Pension

Kadlec, Tomáš January 2018 (has links)
Diploma thesis processes project documentation of a pension using for public accomo-dation and catering. Pension consists of 2 objects – restauration, accommodation. A restauration is designed for 66 guests. A part of the object is a flat for a family of four. It is a single-storey building which is basement and has an attic.The object has rectengular shape, saddle roof and the part of the object is a tercce. The second object uses for accommodation and has a capacity of 36 beds. It is a single-storey building with an attic. The object has rectengular shape and saddle roof. A pension is situated in Perknov which is one of the parts of Havlíčkův Brod. It uses for year-round occupancy. It’s a brick building made of ceramic system. The object is located in slightly hilly terrain from north to south.

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