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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.
51

Nyliberal utopi eller estetisk dystopi? -En multimodal kritisk diskursanalys av svenska visionsbilder

Foberg, Karin, Sand, Gustaf January 2020 (has links)
Visionsbilder över byggprojekt har under de senaste decennierna blivit en vanlig typ av platsmarknadsföring. Visionsbilder kallas även för renderingar och är ett slags digitala collage som försöker övertyga publiken om platsens förmåga att fungera. Till skillnad från fotografier är renderingar sammansatta av visuella element som aktivt valts ut av producenten. Visionsmaterial innefattar en maktdimension då materialet ligger till grund för politiska beslut gällande kommunalt finansierade projekt. Det finns i dagsläget inga studier på visionsbilder ur ett kommunikationsperspektiv i en svensk kontext. Genom en multimodal kritisk diskursanalys undersöker studien vilka värden och löften som synliggörs samt vilka ideologiska funktioner dessa producerar och reproducerar. Analysmaterialet består av visionsbilder med tillhörande text från tre svenska kommuner; Lund, Västerås och Kiruna. Resultatet påvisar en genomgående nyliberal ideologi där både platser, människor och praktiker kommodifieras. De ideologiska funktionerna synliggörs genom teman som; en aktiv livsstil, globalisering, gemenskap via konsumtion, estetiska val och utopiska fantasier. / Images representing a vision of urban redevelopment projects have during the last decades been more frequently used in place marketing. These rendered images are digital collages used to persuade the audience how the place is supposed to work. In rendered images all visual elements are, unlike photographs, composed by the producer. These types of images carry a power relation due to being a part of political decision financed by municipalities. There’s up to this point no research regarding this subject in a Swedish context. This study examines, through a multimodal discourse analysis, which values and promises are made visible and which ideological functions these images and texts produce and reproduce. The analysis covers urban visions regarding three Swedish municipalities; Lund, Västerås, Kiruna. The result depicts a strong commodification and a neoliberal ideology seen through themes like; active lifestyle, globalisation, community via consumption, esthetics and utopian fantasies.
52

From Lada to Folly : Revealing the Origin of Kiruna

Halvorsen, August Junge January 2020 (has links)
"From Lada to Folly" investigates the relationship between an agricultural artefact of Northern Sweden, ladan, and the move of the city of Kiruna. A lada is a structure to store hay which dates back to medieval times as a part of månghussystemet, a Swedish building tradition where each house on a farm had one function. Ladan was analysed on different scales through mapping, photography and model making with the aim of understanding its relation to the landscape. The scale, placement and orientation were the most significant. Subsequently, this information was translated via diagrams to form the basis of a proposal in Kiruna. Four core values are the foundation of Kiruna: timber, water, iron and people. Timber, because the first buildings were built out of wood and because coal from the forest was used to fuel the engines of the mine. Water, as a mode of transportation and a source of energy. Iron, the oar is the main reason why Kiruna exists. People, in the same way natural resources have been extracted out of Kiruna, people have been sent to the city to facilitate this process. Through four corresponding landscapes in the new city centre, the core values forming the origin of Kiruna is revealed. A folly, an unprogrammed structure erected to enhance a landscape and derived from the lada, is placed on each site functioning as a shelter and contextualising the intervention to the region of Northern Sweden. As architecture most often are physical obstacles built to orchestrate our lives, not allowing but limiting our behaviour, this proposal seeks to create free spaces in the city where not the architect but the people themselves can dictate what will happen. Who is the architect to decide whether someone should eat, make love or die in their structure?
53

Saving Erskine — An Example in Circular Heritage Architecture

Friedmann, Léo January 2020 (has links)
This thesis is the story of two housing projects designed by architect Ralph Erskine. The first building, Lassaskog in Växjö built in 1954, is one of the earliest examples of industrialized concrete housing in Sweden. The other one, Kv. Ortdrivaren in Kiruna was built some eight years later following Erskine’s utopian ideas for The Arctic City. Despite their architectural and historical significance, these two buildings are threatened today: Ortdrivaren will be demolished and Lassaskog will be hastily densified.   This thesis is a reaction to these threats, and it is a call for preserving and reusing. Looking towards the near future of circularity, I want to praise for never demolishing a building again.   This leads me to the overarching question of my thesis; how could I sustainably save these two buildings?   The only solution I thought worthy of their architecture was to unite them. Rather than demolishing Ortdrivaren, I propose to deconstruct it and reuse it in Växjö. Thereon, started the project of densifying the Lassaskog estates with new student housing made of repurposed concrete elements from Kiruna.   My objective for this quirky enterprise is to find a methodology for preserving post-war housing estates and for conducting a circular architecture project.
54

Crustal architecture of the Kiruna mining district : Structural framework, geological modeling, and physical rock property distribution

Veress, Ervin Csaba January 1900 (has links)
Rapid technological advancements and growing environmental consciousness created a shifting dynamic of metal demand within the context of contemporary global challenges. The metals play a pivotal role in this transformation and remarkable surge in demand is expected. Mining districts such as the Kiruna area in northern Sweden, provide access to raw materials, assuring supply chain security, sustainability, and an environmentally friendly future. The district is part of the northern Norrbotten ore province, Sweden and is known for hosting the Kiruna-type iron oxide-apatite (IOA) deposits with associated magnetite-hematite-REE ores such as the Per Geijer deposits, and a range of other deposits, including the Viscaria Cu-(Fe-Zn), Pahtohavare Cu-Au and the Rakkurijärvi iron oxide-copper-gold (IOCG) deposits.  As the discoveries of significant near-surface deposits are declining, mining companies face a pivotal choice between pursuing resource extraction from lower-grade reserves or to focus on deeper exploration targets. The geological understanding of the subsurface decreases with increasing depth, and the reliance on geophysical techniques becomes more important in reducing the search space. Using geophysics to locate and understand elements of a mineral system requires a good understanding of the physical and chemical properties of the rocks that can be translated into geological implications. Mineral system knowledge and geological concepts can be translated into geological models that can be further used in geophysical inversions with the aim of improving targeting by iterative modeling. A geophysical inversion is in fact a realization of a physical property model, therefore the value added by the geophysical model is dependent of how well the relationship between the geology and its petrophysical signature is understood. The petrophysical characterization of geological environments offers the possibility to improve the understanding of geophysical responses, serving as a link in iterative geological-geophysical modeling.  The approach presented in the current study includes the building of three-dimensional lithological and structural framework models, and investigating the petrophysical footprint in connection with lithology, alteration, and rock fabric from the Kiruna mining district. Geological modeling and petrophysical characterization are important components within the comprehensive mineral system modeling framework and enhance geophysical investigations aimed at detecting and assessing iron oxide mineral systems. A rule-based hybrid implicit-explicit geological modeling technique proved to be useful in the integration of surface and subsurface data of the Kiruna mining district, and a structural framework and geological model was produced that provides insights into the relationship between lithological units and structures. Drill core observations indicate a competency contrast between lithological units confirming previous surface-based observations. Deposit scale structural analysis in connection with the geological models indicated the proximity of NW-SE to SW-NE trending brittle conjugate fault networks with iron-oxide apatite ore lenses, revealing juxtaposition of individual ore lenses. Complementing structural analysis and geological modeling, petrophysical characterization in connection with lithogeochemical, mineralogical, and textural investigations revealed that density and p-wave seismic velocity can be used as a general lithological indicator, while magnetic susceptibility is influenced by secondary processes. Heterogeneous strain accommodation by lithological units indicates a strong influence on density, seismic properties, and the ferromagnetic properties of the samples. Metasomatic processes alter the intrinsic properties of the samples by increasing or decreasing the physical properties of the rocks from the Kiruna area, by controlling the feldspar, mica, magnetite, and ferromagnesian mineral content. Nevertheless, an extensive sample population must be investigated to understand the large-scale effects. The present work serves as a foundation for quantitatively integrated exploration models that use geological models and petrophysical characterization as calibration tools to model mineral systems.
55

Utilizing a tectonic framework to constrain the mineral system and remobilization in the Kiruna mining district, Sweden

Logan, Leslie January 2022 (has links)
The Kiruna mining district, located in the northern Norrbotten ore province, Sweden, is a geologically and economically important area, being the type-locality for Kiruna iron oxide-apatite (IOA) deposits and also host to a variety of other deposits including syngenetic stratiform exhalative Cu-(Fe-Zn) (Viscaria, Eastern Pahtohavare), epigenetic stratabound Cu ± Au (Pahtohavare), and iron oxide-copper-gold (IOCG, Rakkurijärvi) deposits. However, the timing of IOA versus IOCG within the tectonic evolution is in question based on structural investigations showing Cu- and Fe-sulfides occur in late-orogenic structures. Here we use an established tectonic framework to constrain mineral systems (tectonic/thermal drives, metal and ligand sources, fluid pathways, traps, remobilization mechanisms) related to the early and late phases of the Svecokarelian orogeny in the Kiruna mining district. U-Pb zircon geochronology of intrusions in the district indicates a thermal drive was present during the early phase of the Svecokarelian orogeny from ca. 1920-1865 Ma, however remains enigmatic for the late Svecokarelian orogeny. Zircon grains from a magnetite-ilmenite gabbro yielded an age of 1881 ± 8 Ma, coeval with the Kiirunavaara IOA deposit and suggested to represent an important generation of mafic magmatism related to the ore. Lithogeochemistry of early bimodal Svecokarelian intrusions in the district indicates a within-plate to active continental margin environment with a volcanic arc affinity, pointing to a back arc environment. Epsilon Ndi and 87Sr/86Sri values calculated from the U-Pb ages for the igneous intrusions were compared to samples of ore-related alteration from epigenetic Pahtohavare and Rakkurijärvi deposits, district greenstone, and Archean samples. Results show that each deposit sourced Sr and Nd from a variety of rocks suggesting broad fluid transport. Each deposit has a distinct Sr mixing trend suggesting they formed from different ore-forming fluids and pathways. This is supported by new structural data that constrain the folding event and the ore-related quartz-carbonate-sulfide veins in the Pahtohavare area to a late orogenic timing, compared to the early orogenic timing of Rakkurijärvi. Sulfide trace element and sulfur isotope data from structurally constrained ores within the tectonic framework also record distinct characteristics between early and late deposits. However, remobilization of early Pahtohavare sulfides associated to an increase in Co content and heavier sulfur isotope compositions is recorded. The results of this study illustrate that using a structural framework approach to constrain the ingredients of mineral systems is a powerful strategy for interpreting ore deposit processes in tectonically complex terrains where both IOA and IOCG deposits occur.
56

RECLAIMING KIRUNA : Ecological reclamation of post-exhaustion Kiruna mine

ANAND, DIKSHA January 2020 (has links)
In brownfield regeneration models, extraction sites are often left out of the question because of degradation, severe contamination, or economic viability and are usually abandoned, after the minimal remediations. These exhaustions not only impact the environment and economy in spatial relations but also influence the growth of the communities cultured by them. With millions of abandoned sites around the globe, there is a demand for building a vision that develops - the ideas of emergence and diversification over time and space, as a base framework for similar towns and communities before they disappear. Underpinning the urgent need and evolving theme of ecologies, 'Reclaiming Kiruna' is an investigation of a vision for a post-exhaustion site of Kiruna mine, which is the world's largest underground mine, by developing landscape ecologies in the present framework that builds and adapts with time and space before the mine gets exhausted. The project reveals the concept of landscape as an amalgamation of production and recreation ecologies, synergizing with the existing potentials of nature, resources, and society. The work focuses on translating the knowns and unknowns of three time periods, synced with proposed plans of the New Kiruna settlement area, through programs of care and thinking that involve, engage, and encourage people (of Kiruna) in redefining the image of Kiruna beyond just a mine. The project unfolds new prospects offered by planned urban transformations, mining systems, and changing climate, which are integrated into building new economies and relations. The project is limited by the uncertainty of the future but attempts to initiate a dialogue in finding new positions as urban designers to contest with the present frameworks in building alternatives of change and novelty, for a sustainable future.
57

EBSD Investigation of High-Temperature Magnetite from Apatite-Iron-Oxide Deposits: Implications for the Formation of Giant Kiruna-Type Deposits / EBSD-undersökning av högtemperatur magnetit från apatit-järnmalmsfyndigheter: Implikationer för bildningen av gigantiska fyndigheter av Kiruna-typ

Henriksson, Jens January 2022 (has links)
European iron production is to a large extent dependant on massive Kiruna type apatite-iron ore deposits. In this contribution, high-temperature magnetite samples from apatite-iron-oxide deposits are investigated by means of Electron Backscattered Diffraction. However, the origin of Kiruna-type deposits is still unresolved. Although magmatic processes are likely, it is not clear how small-scale processes can form giant Kiruna-type deposits. The sample suite consists of magnetite samples from six global apatite-iron-oxide deposits: the famous Kiirunavaara deposit and the Malmberget deposit, both located in northern Sweden, the Grängesberg deposit in south-central Sweden, the iconic El Laco deposit in north-eastern Chile, the Bafq deposit in central Iran, and the Varena deposit in south Lithuania. Fe-O systematics has been conducted to complement existing δ18O and δ56Fe isotope data and ensure magmatic origin of the samples from the Malmberget deposit (n=6) and the Varena deposit (n=2). This is the first effort to characterise magnetite samples from apatite-iron-oxide deposits utilising EBSD. In total, twelve EBSD maps have been produced. Evaluation of the EBSD data have been performed to quantify the preferred orientation of the magnetite crystals. Four deposits, with Kiirunvaara being the prime example, shows no preferred alignment of the magnetite crystals. Whereas the El Laco samples exhibits a strong preferred alignment of {111}. The EBSD data from magnetite samples in equilibrium with a magmatic source indicate that apatite-iron-oxide deposits are formed in both intrusive and extrusive environment and that magmatic crystal accumulation is a key process in aggregating magnetite to form large and even giant Kiruna-type deposits. / Europeisk järnmalmsproduktion är i stor utsträckning beroende av massiva apatit-järnmalmsfyndigheter av Kiruna-typ. I det här arbetet, undersöks magnetitprover av hög-temperaturs ursprung från olika apatit-järnmalmsfyndigheter med Elektron Bakåtspridande Diffraktion. Bildningsmekanismen av apatit-järnmalmsfyndigheter av Kiruna-typ är än idag oklar. Bevisen indikerar magmatiska bildningsprocesser, det är dock fortfarande oklart hur småskaliga magmatiska processer bildar gigantiska apatit-järnmalmsfyndigheter av Kiruna-typ. Provserien består av magnetitprover från sex globala apatit-järnmalmsfyndigheter: den världsberömda Kiirunavaara fyndigheten och Malmberget fyndigheten, båda lokaliserade i Norrbotten, Sverige, Grängesberg fyndigheten i Bergslagen, Sverige, den ikoniska El Laco fyndigheten i nordöstra Chile, Bafq fyndigheten i centrala Iran, och Varena fyndigheten i södra Litauen. För att fastställa ett magmatiskt ursprung och komplettera befintlig δ18O och δ56Fe isotopdata har Fe-O-systematik utförts på magnetitproverna från Malmberget (n=6) och Varena (n=2). Det här är den första dokumenterade EBSD-undersökningen av magnetitprover från apatit-järnmalmsfyndigheter. Totalt tolv EBSD-kartor har producerats. Utvärdering av EBSD-data har utförts för att kvantifiera den föredragna riktningen på magnetitkristallerna. I fyra fyndigheter, med Kiirunvaara som typexempel, uppvisar magnetitkristallerna ingen föredragen riktning, medan magnetitproverna från El Laco uppvisar en tydlig föredragen riktning längs {111}. EBSD-data från magnetitprover i jämnvikt med en magmatiskkälla påvisar att apatit-järnmalmer bildas i både intrusiva miljöer och extrusiva miljöer och att magmatisk ackumulation är en nyckelprocess för att aggregera magnetitkristaller och bilda stora till gigantiska apatit-järnmalmsfyndigheter av Kiruna-typ.
58

Making Place for Space : a History of 'Space Town' Kiruna 1943-2000

Backman, Fredrick January 2015 (has links)
Science and technology have a tendency to clump together in places where they spawn other forms of societal activities. Sometimes these places become famous through processes known as place-making, or the social construction of place. Because the scientific and technological activities affect the places, and the places conversely affect the science and technology, it is relevant to study how and why these connections emerge. This dissertation examines the particular case of the northern Swedish town of Kiruna, which has become known for being a `space town' because of its scientific, technological, and other activities that relate to the near space around the earth. The overall objective is to analyse the processes underlying the making of Kiruna as a space town in the period 1943--2000. Five parts make up the study. First is an examination of how the development of space physics research in Kiruna led to the setting up of a scientific observatory. The second part studies how the Swedish participation in the European Space Research Organisationmade Kiruna the place for a rocket base. Next follows an analysis of how local business efforts contributed to forming a new satellite technology business and the Space House office building. The fourth part concerns how the visions to establish a space `university' eventually led to the emergence of the Space Campus. Last is an epilogue that briefly analyses the space tourism efforts in Kiruna. A central finding is that the space town has emerged as the result of entwined processes where, on the one hand, ideas about the near space around the earth have led to new activities and physical structures, and, on the other hand, these new activities and built structures conversely have inspired to new ideas. Of importance is also the geographical place where these developments have occurred. Here, a reoccurring argument to placing the activities and structures in Kiruna was the town's geographically favourable location for specific scientific and technological activities. Another finding is that the development has gradually led to the emergence of a kind of identity or notion of Kiruna as a particular place for space activities. Although this form of place-making has occurred largely through spontaneous processes, it was also the result of intentional efforts. Together, these different place-making processes have formed the `space town' of Kiruna.
59

Denitrification in a Low Temperature Bioreactor System : Laboratory column studies

Nordström, Albin January 2014 (has links)
Denitrification is a microbially-catalyzed reaction which reduces nitrate to N2 through a series of intermediate nitrogen compounds. Nitrate is a nutrient and its release into the environment may lead to eutrophication, depending on the amount that is released and the state of the recipient. The release of nitrate from the mining industry in Kiruna (Sweden) has been identified as an eutrophication risk, and a denitrifying bioreactor is to be constructed at the site to reduce the nitrate release.Since the denitrification rate decreases with temperature and the temperature in Kiruna during large parts of the year drops below 0˚C, the denitrifying bioreactor therefore has to be designed for the site-specific environment in terms of flow rate and hydraulic residence time. Laboratory column studies are used to study and determine the nitrate removal rate in a low temperature environment (5˚C) with pine wood chips as reactive matrix/ electron donor; the input solution had an average concentration of 35 mg NO3-N/L and a high sulfate concentration. Nitrate removal was studied as a function of hydraulic residence time and temperature. Parameters that were monitored include pH, alkalinity and concentrations of ammonium, nitrite and sulfate in the effluent from the columns. On three occasions, samples were gathered along the flow path in the columns (concentration profiles) such that changes in nitrate, nitrite, and occasionally ammonium concentration could be studied in relation to each other. The study concluded that a denitrifying bioreactor utilizing pine wood chips as the reactive matrix is a suitable option for nitrate treatment in a low temperature (5˚C) environment. Under the conditions of the study, effluent nitrate, nitrite, and ammonium concentrations are below limits established in legislation. Nitrate removal rates are given for zero-order nitrate reduction and overall first-order nitrate reduction, as the concentration profiles revealed a decrease in nitrate removal rate as nitrate concentration dropped below 3 mg NO3-N/L. / Nitrat är ett näringsämne som kan orsaka övergödning vid utsläpp, beroende på halterna och recipienten. Växterna som tar upp kväve kommer så småningom att dö och sjunka mot botten där de förmultnar. Förmultningen kräver syre, och vid ökad växtlighet så ökar även konsumtionen av syre då det finns mer organiskt material att bryta ned. Detta leder i slutändan till syrefria områden, där djurliv och växtlighet är mer begränsade. Nitratutsläpp från gruvindustrin i Kiruna har blivit identifierad som en potentiell övergödningsrisk och en denitrifierande bioreaktor ska därmed installeras för att minska utsläppen. Denitrifikation är en mikrobiell reaktion som reducerar nitrat till kvävgas genom en serie av intermediära kväveföreningar. En denitrifierande bioreaktor använder sig utav denitrifikation för att minska nitratkoncentrationer i vatten som passerar genom bioreaktorn som består av huvudsakligen; (1) bakterierna som sköter denitrifikationen, och (2) en kolkälla som fungerar som ”mat” till de denitrifierande bakterierna, Hastigheten varvid nitrat omvandlas till kvävgas genom denitrifikation, minskar med temperatur och den denitrifierande bioreaktorn måste därmed anpassas till omgivningen där den ska placeras med avseende på uppehållstid i reaktorn. Uppehållstiden måste vara tillräcklig för att minska nitratkoncentrationen till önskad nivå, men samtidigt så får uppehållstiden inte vara för lång då andra ämnen kan reagera och bilda ofördelaktiga produkter vid låga nitratkoncentrationer. Kolonnstudier i en låg-tempererad miljö (5˚C) är ett första steg för att studera hastigheten av nitratförbrukning i en sådan omgivning, och används i detta arbete med träflis av tall som kolkälla. Parametrar som påverkar, och varierar som ett resultat av, denitrifikation (exempelvis pH och sekundära föroreningar) övervakas. Hastigheten av nitratförbrukning som fås från kolonnstudierna kan sedan används som riktlinjer för konstruktionen av en denitrifierande bioreaktor i fältskala i Kiruna. Studiens slutsats är att en denitrifierande bioreaktor med träflis av tall som reaktivt medium är ett fungerande alternativ för nitrat reducering i en lågtempererad miljö (5˚C) då nitrat effektivt reduceras till under gränsvärden fastslagna i lag. Även andra potentiella biprodukter (exempelvis nitrit och ammonium) som kan resultera från den miljö som den denitrifierande bioreaktorn ger upphov till är under de gränsvärden som finns fastslagna i lag.
60

Accident Risk and Environmental Assessment : Development of an Assessment Guideline with Examination in Northern Scandinavia

Lundkvist, Markus January 2005 (has links)
In environmental impact assessment (EIA), accident risk should be considered as one impact. However, few studies have compared assessed risk levels with documented accidents. There is thus a need for assessing accuracy of risk assessment methodologies. The aim of this study was to develop and examine a risk assessment guideline based on environmental assessment. The guideline examination was carried out along the railway and the road between Kiruna and Narvik, Northern Scandinavia. The examined hazards were avalanches, debris flows, rock falls, slush flows, torrents, moose and reindeer. Documented accidents were quantified into an accident level. For each hazard type, six sections/sites were assessed. The propensities of these hazards were analysed through environmental assessments, especially by utilising geomorphology. Then, the accident densities along the sections/sites were compared with assessed accident phase indices describing risk and hazard in both spatial and temporal dimensions. The average uncertainty factors for both the risk and the hazard indices were about 5. This implies a fairly good precision. Risk and hazard indices were also rated and compared to the accident density rates. Thereafter, railway and road information was split up as different proposal alternatives in an EIA context. The total risk for each proposal was compared with the total accident density. The risk assessment guideline proved to be cost-efficient, rapid and relatively reliable in comparing accident risk.

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