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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.
41

KOMMUNAL PLANERING FÖR URBANA GRÖNOMRÅDEN / Municipal planning of urban green spaces

Schultz, Maria January 2020 (has links)
During the last centuries, Sweden has become more urbanized and today 85% of the population are living in urban settlements. A future challenge for city planners is climate change, which is expected to lead to higher sea levels, rising temperatures, less snow and larger amounts of rainfall with more extreme precipitation. One approach for cities to deal with these challenges is to preserve urban greenspaces and the ecosystem services that they provide. For that reason, this essay aims to examine how municipalities are planning their urban green spaces and which motives are behind the planning for different ecosystem services. This was accomplished through a content analysis where three municipalities’ (Knivsta municipality, Uppsala municipality and Upplands Väsby municipality) planning and goal documents were examined. With the purpose to get knowledge about which ecosystem services were the most reoccurring. The results showed that the two most reoccurring ecosystem services in the three municipalities were recreation and biodiversity. The third most reoccurring ecosystem service in Uppsala municipality and Upplands Väsby municipality was water regulation, while in Knivsta municipality it was cultural heritage. The motives behind why the green spaces with these ecosystem services were seen as important were to prevent fragmentation of pathways and habitats important for biodiversity, and to ensure access to close and accessible greenspaces during urban infills and expansion. Furthermore, urban green spaces can be a part of the work for climate change adaption and for handling extreme precipitation. / Under de senaste århundrandena har Sverige urbaniserat och idag bor 85% av befolkningen i tätorter. En framtida utmaning för stadsplanerare är klimatförändringar vilka förväntas leda till höjd havsnivå, ökande temperaturer, mindre snö och ökad nederbörd med fler tillfälliga extrema nederbördsmängder. Ett sätt för städer att hantera dessa utmaningar är genom att bevara urbana grönområden och de ekosystemtjänster som de bidrar med. Av den anledningen syftar detta arbete att undersöka hur olika kommuner planerar för sina urbana grönområden och vilka motiv som finns bakom planerandet av olika ekosystemtjänster. Detta genomfördes genom en innehållsanalys på tre kommuners (Knivsta kommun, Uppsala kommun och Upplands Väsby kommun) planerings- och måldokument och då undersöktes vilka ekosystemtjänster som var mest återkommande. Resultatet visade att de två ekosystemtjänsterna som var mest återkommande i alla tre kommuner var rekreation och biologisk mångfald. Den tredje största ekosystemtjänsten var i Uppsala kommun och Upplands Väsby kommun reglering av vattenflöden medan den i Knivsta kommun var kulturarv. Motiven bakom varför grönområden med dessa ekosystemtjänster ansågs vara viktiga var för att hindra fragmentering av livsmiljöer och spridningsvägar viktiga för biologisk mångfald och för att se till att tillgången till nära och tillgängliga grönområden förstärks vid förtätning och tillväxt av staden. Dessutom är grönområden en viktig del inom städers klimatanpassningsarbete och för att förbereda städerna för en ökad mängd nederbörd.
42

REMANUFACTURING IN WIND POWER: A MULTI CRITERIA DECISION ANALYSIS APPROACH

Robertson, Graeme January 2020 (has links)
Due to the rapid growth of the wind energy market over the last decade, the future of the industry will consequently see the dismantling of many wind turbines, both due to wind turbines reaching the end of their service life and to make way for surpassing technology, leaving behind a large amount of material that must be dealt with. Furthermore, due to the advancing technology of wind turbines, there has been a decline in the number of medium sized wind turbines being manufactured. This study aims to address the problem of future waste mitigation, whilst attempting to capture the medium scale market. As such, the study has looked at the idea of transitioning towards a circular economy, in which wind turbines are not considered as waste at the end of their service life, but rather an opportunity to recapture value through remanufacturing. This was approached by identifying the driver and barriers of remanufactured products, utilising knowledge from other industries with developed remanufacturing sectors. A Multi-Criteria Decision Analysis (MCDA) has been performed using the PROMETHEE II method with the objective of drawing a comparison of three scenarios, enveloped by a theoretical wind turbine selection project. The scenarios were created by the author and considered the implementation of a new wind turbine and remanufactured wind turbines. Upon examining the results of the multi criteria decision analysis, it was seen that the benefits of implementing remanufactured turbines were preferred by the majority of the stakeholders involved.
43

Study of the Taxonomy of Carnivores from the Eocene-Oligocene of the Quercy Area, France / En studie av eocena-oligocena rovdjurstaxonomi i Quercyområdet, Frankrike

van der Hoek, Julien January 2021 (has links)
The Quercy area of France is an important site for mammal palaeontology, yet 19th century collections of this area, such as the one in the Department of Palaeobiology, Naturhistoriska riksmuseet, remain understudied due to not being well updated taxonomically and correlated stratigraphically. An updated taxonomy was created for the postcranial material of the collections, as well as the dental material originally identified to the amphicyonid genera Amphicyon, Haplocyon and Pseudocyon through study of morphological characteristics and measurements. Most of the postcranial material was assigned to a family, which would allow comparison of different morphotypes to gain insight into questions on locomotion, posture and overall ecology. The dental material was reidentified to include the amphicyonids (bear dogs) Amphicyonidae gen. indet. sp. indet, Pseudocyonopsis, Cynelos and Haplocyon, as well as the mustelid Ischyrictis zibethoides. Stratigraphic ranges for the identified species were obtained from existing studies. This updated taxonomy would allow for future study of this material to improve the overall understanding of Quercy, as well as the taxa present in these localities.
44

Transformationsmetoder : En fallstudie över ett detaljplanerat område i När socken / Transformation methods : A case study of a detailed planned area in the När parish

Magnusson, Roger January 2021 (has links)
Region Gotland har påbörjat digitalisering av samhällsbyggnadsprocessen där kvalitetssäkring av digitala fastighetsgränser ingår. Rapporten tar upp teori, metod, resultat och analys av transformationsmetoder.En del av arbetet går ut på att ta fram lämpliga transformationsmetoder för ej återfunna gränsmarkeringar.Regionen har långa väntetider på bygglov. För att underlätta och minska handläggningstiden kommer de digitala detaljplanerna tolkas efter nymätta eller transformerade gränser. Digitala registerkartan som används i kartframställning har idag bristande kvalitet i form av felaktigt placerade gränser. I arbetsgruppen på regionen har beslut fattats att återfunna gränsmarkeringar inom detaljplanerade områden kommer att mätas och övriga kommer att transformeras med hjälp av data från förrättningsakter för att säkerställa att det digitala underlaget stämmer.  Därefter kommer en webbapplikation skapas där fastighetsägare snabbt kan få svar på om den tänkta byggnationen är planenlig.Inmätning av fastighetsgränser utfördes med N-RTK-mätning samt fri totalstationsmätning som etablerades med GNSS-inmätta punkter.Koordinater för gränspunkter har tagits fram med transformationsmetoder där gränsmarkeringar inte har hittats exempelvis på grund av att stenmurar och vägar byggts över gränsmarkeringarna, gränsmarkeringar som inte längre har samma placering på grund av trädrötter som flyttat dem och gränsmarkeringar som placerats tillbaka felaktigt efter grävning vid avloppsbyte.Efter analysen av data konstateras att i detaljplanen 09-NÄR-366 är unitär transformation att föredra därför att skillnaderna i grundmedelfelen samt skalfaktorerna i transformationerna inte är stora samt att unitär transformation inte ändrar längder mellan gränsmarkeringarna och arealerna i fastigheterna. / Region Gotland has begun digitisation of the community building management, which include quality assurance of property boundaries. This report addresses theory, method, results and an analysis of the transformation methods.To require a building permit, the region has long waiting times. In order to facilitate and reduce the processing time, zoning plans will be interpreted according to their documents. Property boundaries within the zonings will be measured and transformed to improve quality and to verify the property boundaries.The measurements were performed with N-RTK measurement and setup of total station with GNSS-measured points.Coordinates for boundary markings have been updated with transformation methods where boundary markings have not been found. For example, where stone walls and roads have been built over the boundary markings, where boundary markings no longer have the same location due to tree roots moving them, or where boundary markings have been placed incorrectly after excavations.This report shows, that in this specific case, the difference between the transformation methods are small, therefore suggesting that the Unitary transformation is preferred because of the minor difference in distance and scale factors, and because Unitary transformation does not change lengths and areas.
45

BUILDING A SUSTAINABLE FUTURE WITH WIND ENERGY: AZERBAIJAN’S AMBITIOUS PLANS FOR KARABAKH

Abdurahmanov, Fagan January 2023 (has links)
Transitioning to renewable energy is critical for reaching global sustainable development goals. As an oil-rich country, Azerbaijan has recognized the need to develop its renewable energy sector. It has set ambitious goals for increasing the share of renewables in its energy mix and establishing a green energy zone in the Karabakh region. The purpose of this master's thesis is to assess the potential of wind energy in Azerbaijan's Karabakh region and surrounding areas and identify the best scenario for its development. Four scenarios were evaluated via the PROMETHEE II Multi-Criteria Decision Analysis (MCDA) method based on their economic, environmental, technological, and social factors. Interviews with real stakeholders were undertaken to elicit weights for the criteria, and a sensitivity analysis was conducted to evaluate the robustness of the results. The findings were shared with the stakeholders, and their input was integrated into the final analysis. According to the findings, Scenario 4, which includes more installed capacity and increased investment, is best suited for the growth of wind energy in the Karabakh and surrounding areas from the perspective of developer and governmental body. In contrast, renewable energy expert and the public prefer Scenario 1, with less land use and less capacity. The findings indicate that for the effective development of wind energy in the area, a balanced approach taking into account the opinions of all stakeholders, is essential. This study contributes to Azerbaijan's long-term development by offering valuable insights into the potential of wind energy in the Karabakh region and surrounding areas and supporting informed decision-making for its expansion.
46

Soil compaction and the effect on infiltration in urban green environments : A study based on field measurements and HYDRUS 1D modelling

Novikova, Anastasia January 2023 (has links)
The consequences of recent flooding and extreme rain events have highlighted the importance of proper urban planning and preventative measures for storm water management. As cities become more urbanized the significance of permeable surfaces such as parks and other urban green spaces increases which infiltrate the water into the ground. Agricultural research has for many years emphasized the effect of compaction on soil parameters and how, not only the crop yield reduces but also how the infiltration decreases. This thesis aims to study how the infiltration rate, bulk density and soil resistance changes with compaction through field experiments where a vehicle is let to roll over an urban green area. The thesis will also simulate rainfall over five theoretical soils that can be found in urban environments exposed to compaction to determine what significance compaction has on surface runoff. The modelling software HYDRUS-1D will be used so simulate rain fall events on the different soils. The rain events simulated will be based on the five hyetographs that best represent Sweden’s rain events, based on historical data. A CDS rain will be simulated as well. They will be simulated for a 2, 10 and 100 year return period. A literature study will also be conducted to determine how relevant freeze-thaw cycles are to the soil parameters. It is since previously known that freeze-thaw cycles can improve aggregate stability, increase soil particle fragmentation which can lead to less soil penetration resistance and even partially return the soil conditions to those prior to compaction, but the process does not extend to layers beyond 40 cm. The field experiment results showed a clear decrease in infiltration rate with increasing number of vehicle passes. There was no clear correlation between bulk density and the number of vehicle passes. This result is attributed to the relatively light weight of the vehicle used as well as the heterogeneity of the soil. The cone penetration measurements showed an increasing resistance with increasing number of vehicle passes for only one of the three measured sites, with the most resistance being measured in a pathway on the green area. The insignificant results of one of the two other sites are attributed to wet weather conditions and unknown underlying material. The HYDRUS 1D simulations showed that a higher sand content mitigates the effects of soil compaction and leads to less runoff. The soil classified as sand (93% sand) had no runoff, the loamy sand (80% sand) had mild runoff. When comparing a sandy loam (60% sand) and a clay soil it is concluded that the sandy loam is more sensitive to soil compaction as more compaction leads to more runoff compared to the non-compacted scenario. The clay soil has little variation between the compaction scenarios but has generally more surface runoff in total. Soil texture therefor affects the surface runoff more than soil compaction. Most amount of runoff was generated by the two hyetographs which had a late peak intensity, most likely due to the soil already being saturated when the peak occurs. The runoff also increases with the return period of the rain event for both the hyetographs and the CDS rain.
47

Do Clay Minerals affect the thickener operationin Chuquicamata mine, Calama, Chile?

Soto, Chris January 2020 (has links)
Chuquicamata mine mineralogy has been studied performing both X-Ray Diffraction (XRD) and X-RayFluorescence (XRF) to determine whether there is any influence in the thickener operations. Thetargeted minerals were the clay group because of their detrimental effect on mining operations asmodify the rheology of the suspensions. The operation stages most affected by the presence of the clayminerals are gravity separation, milling, conveyor belts, flotation and specially thickener operations. Inorder to cope with Chuquicamata production, the plant is constantly fed from a neighboring ore calledRadomiro Tomic (RT) ore, a secondary sulfide enrichment. At Chuquicamata, the thickener operatorfeedback has been pointed out that every time the concentrator plant is fed in high ratio with this so-called RT ore the mineral processing is hindered. For this reason, RT ore samples from a criticaloperation day were sent to Sweden for mineralogical analysis. In addition, flotation tailings from thethree Chuquicamata concentrator plants were also sent aimed to perform thickener pilot tests. In thismanner, it was seen if it could be possible to achieve new operational strategies in Chuquicamatathickener operations given the current Chuquicamata mineralogy and physical conditions in the flotationtailings.From the XRD analysis, the following clay minerals were identified in order of abundance: Illite>>Kaolinite>Smectite Thus, illite reached up to 23.3vol% being the highest clay amount, followed by lower case kaolinite up to2.5% and up to 1% of smectite values correspond for the RT sample. However, the clay content in theflotation tailings samples were less than expected. Also, clay Crystallinity was also assessed for its abilityto interfere negatively with the pulp rheology, and the results showed that there is a strong link amongpoor crystallized smectite clay with the semi-autogenous mill compare to those samples where themilling was performed in the traditional steel media. Along with the three clay minerals found, quartz,potassic feldspar, and plagioclase were also identified, accounting for up to 76% of the representativesample. The silicate minerals are thought to be problematic in Chuquicamata thickener operations givenits high amount, especially in <2 µm size.For the thickener tests, three types of polyacrylamide were used plus the current Chuquicamataflocculant. Prior to the sedimentation batch test, the rheology of the flocculants was measured in arange of 0.02%w/w to 1%. It was found that flocculant concentrations between 0.02 to 0.05%w/w themost suitable in terms of avoiding suspension rheology increase. After establishing suitable flocculantconcentrations solutions, these were used in the thickener pilot tests at conditions similar to thoseperformed in Chuquicamata thickener operations. Two criteria were used to analyze the bestsedimentation conditions: Initial settling rate (ISR); and Turbidimeter. At pH in a range of 11-12 and 15%solid, bridging flocculation probed to be the most suitable conditions for Chuquicamata thickeneroperations. Moreover, a polyacrylamide blend was tested aiming to achieve high sedimentationperformances. The flocculant blend reached both the highest initial sedimentations rate up to 48m/hand turbidity values below 20NTU at addition rate 5g/t and 7g/t. On the other hand, Chuquicamatacurrent flocculant only reached the highest values of 36m/h and turbidity of 40NTU at an addition rateof 5g/t. In this way, the current work established that conditions at Chuquicamata thickener operation 4can be improved by understanding the absorption process among particle-polymer and mineralogy ofthe mine.Hence, the implication of this work to Chuquicamata mine is a better knowledge of its mineralogyespecially concerned with it is believed that clay minerals are not the only mineralogical factors thatcould be hindering thickener operations in Chuquicamata. Other factors that also could be problematicare: high content of silicates; clay crystallinity, particle size and mixed clay. In addition, the improvementin the thickener sedimentation operations will bring better use of the water by increasing therecirculation towards the concentrator area in a friendly way with the environment and communitiesthat also demand water in the arid region of the Atacama Desert.
48

Winter wheat exudates : Improving wheats resilience to drought

Haverland, Freja January 2024 (has links)
Wheat (Triticum aestivum) is a crop that dominates the diets of about 35% of the world's human population. But wheat yields can be severely affected by drought. Therefore, in this experiment, root exudation of winter wheat was compared to find out how exudation changes during drought stress. This was done by using control plants that were compared to plants that experienced 8 days of drought and subsequently, 3 days of rewetting. Moreover, it was explored which one of two wheat genotypes, Capo or Aristaro, is better adapted to drought by measuring plant physiology and if beneficial rhizosphere microorganisms could help alleviate drought in wheat. Exudations were analysed using a photometer. It was found that drought and rewetting treatment influenced shoot dry weight, shoot water content, relative chlorophyll, as well as exuded phenols, sugars and amino acids. Aristaro was found to be more drought tolerant, because Aristaro plants had higher and more stable shoot water content, lower non-photochemical quenching (NPQ(T)), and exuded more phenols and amino acids, which could help recruit plant-growth promoting rhizobacteria. However, Capo might be able to avoid drought through early maturity and can therefore be used in regions where drought occurs later in the year. The implications of this experiment are therefore useful for improving wheats resilience to drought and food security with use of microorganisms.
49

Ajourhållning av en stadsmodell med multipatch i LOD2.2 : Utveckling av Karlstads kommuns ajourhållning av stadsmodellen genom att rita upp geometrin i geografiska CAD-program / : Developing Karlstad municipality’s update method of their city model by shaping geometries in geographic CAD-program

Dovrén, Emil January 2023 (has links)
Karlstad municipality owns an urban model made by external companies. The municipality wants to be able to update the model on its own. Today the municipality update the model using UAV photos processed in Agisoft Metashape. This study aims to investigate the option of creating 3D objects with ArcGIS Pro and photos of the building. The building used in the study is an apartment house located at Rudsberget in Karlstad.This objective is to investigate the advantages and disadvantages of both techniques, to give the municipality a better basis for the decision of which technique is the most suitable to create models of buildings. The building model is already created by a company that created the urban model and exists as a UAV model. The building model acts as a reference since the buildings, in general, are created in this way. Positional accuracy, size, plainness, and cost of data are the parameters of the models that will be measured. The UAV model has better positional accuracy. The size was also more accurate with the UAV model because it has better height and volume accuracy, but the model made in the study had a better footprint. The model in the study also has better plainness, looks, and has a lower data cost. The conclusion is that the model created in the study is a good alternative to the UAV model. Another conclusion is that knowledge about height and understanding of the contexture of the building will make a better model. / Karlstads kommun innehar en digital stadsmodell bestående av byggnadsmodeller omfattande hela Karlstad tätort. Byggnadsmodellerna har tillverkats av en extern konsult vid namn Terratec. Dessa modeller kallas här Terratecs ursprungsmodell. Kommunen vill själv ajourhålla modellen när byggnationer och andra förändringar sker av staden. Idag skapar kommunen egengjorda fotogrametiska modeller som är byggnadsmodeller tillverkade av flygfoton från UAV. Flygfotografierna bearbetas till punktmoln och sedan byggnadsmodell i programvaran Agisoft Metashape. Studiens syfte är att undersöka kvaliteten för en alternativ teknik, nämligen att använda CAD i programvaran ArcGIS Pro, här kallad egenritad CAD-modell. Till stöd ska fotografier och indata från en inmätning användas.I studien genereras en modell av ett punkthus i bostadsområdet Rudsberget i Karlstad. Modellen jämförs sedan med den egengjorda fotogrammetiska modellen, som tillverkats som ett examensarbete av William Carlsson, för att värdera fördelar och nackdelar med respektive teknik. De två modellerna jämförs sedan mot samma byggnad i Terratecs ursprungsmodell.I studien jämförs modellernas lägesnoggrannhet, storlek, begränsningasarean och minnesåtgång. Resultatet visar att den egengjorda fotogrammetiska modellen har något bättre lägesnoggrannhet. Den egengjorda fotogrammetriska modellen uppvisar också en mer noggrann höjd medan den egenritade CAD-modellen uppvisar en mer noggrann area i jämförelse med referensmodellen. Den egengjorda fotogrammetriska modellens volym är mer lik. Egengjorda CAD-modellen har även en mer tillförlitlig begränsningsarea.Slutsatsen är att den egenritade CAD-modellen är ett bra alternativ. Slutsatsen är också att vetskap om byggnadens höjd och form gör genereringen av en egenritad CAD-modell betydligt lättare.
50

Modellering av Siljans strandkant omkring tidigmesolitisk tid för att identifiera arkeologiskt intressanta platser

Sahlin, Anders January 2017 (has links)
During the planning stages of new business start-ups in Leksand, it was decided that an archaeological survey of the area in question was to be performed in 2013. The reason for this was that in the 1980s findings of Stone Age character had been found in the clay field that once was there. In the 2013 survey, it was found that the area is a stone age settlement, dating back close to 9, 600 BP ( early mesolithic age). Stone age settlements are usually very close to rivers or lakes. For this reason, there arenormally no archaeological surveys of areas not adjacent to water. But this settlement was found on a clay field, 100 meters from the nearest water, Limsjön.The reason for this is that the water level at the time of the settlement's construction was higher in the ground than today. This is b ecause of the uplift of land that occurs in Sweden. The settlement, which was built close to 10,000 years ago was built when the water level was about 10 meters above todays water level at Limsjön. The purpose of this work is to produce maps showing where the whole Siljan shore line was at the time when the first people settled there. This will be done using information for the water surface position close to the settlement from 10,000 years ago to. The old shore line is several 10’s of kilometers long. To get more specific areas the maps also show suitable settlement areas based on the soil types that people have settled on during that time. These maps will then be used as a supportfor choosing areas where archaeological surveys might be of interest. / Under planeringen av nya företagsetableringar i Leksand valde man att 2013 utföra en arkeologisk undersökning av det aktuella området. Anledningen var att man på 1980-talet funnit fynd av stenålderskaraktär i den leråker som låg där då. I undersökningen framkom det att området är en stenåldersboplats, daterad till som äldst omkring 9 600 BP ( tidigmesolitisk tid). Stenåldersboplatser finns i regel i mycket nära anknytning till vattendrag och sjöar. Av denna anledning görs det normalt sett inga arkeologiska undersökningar av denna typ om området inte ligger intill vatten. Men denna boplats hittades alltså på en leråker, 100 meter från det närmsta vattnet, Limsjön. Anledningen till detta är att vattennivån vid tiden för boplatsens uppförande låg högre upp i terrängen än vad den gör idag. På grund av landhöjningen har vattenytans nivå sjunkit i terrängen. Boplatsen som uppfördes för nära 10 000 år sedan uppfördes när vattenytan låg cirka 10 meter högre upp i terrängen vid Limsjön. Syftet med detta arbete är att utifrån information för vattenytans läge vid boplatsen för 10 000 år sedan ta fram kartor som visar var hela Siljans strand låg i terrängen för tiden då de första människorna bosatte sig där. Den forna strandkanten är flera mil lång. För att få fram mer specifika områden ska kartorna även visa områden som är lämpliga boplatsområden, utifrån vilka jordarter som människorna har bosatt sig på under den tiden. Dessa kartor ska sedan kunna användas som underlag för var arkeologiska undersökningar skulle kunna vara intressanta att genomföra.

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