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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.
511

Využití laboratorní/terénní spektroskopie a obrazových dat dálkového průzkumu Země pro studium vegetace / Laboratory/Field Spectroscopy and Remote Sensing Image Data for Vegetation Studies

Červená, Lucie January 2018 (has links)
Dominant vegetation species of two structurally and functionally different montane ecosystems were studied by means of laboratory and field spectroscopy and remote sensing image data: (1) a homogeneous human-influenced evergreen coniferous forest represented by a Norway spruce forest in the Krušné hory Mountains and (2) a heterogeneous natural ecosystem of a relict arctic-alpine tundra in the Krkonoše Mountains with predominance of grasses. The first part dealing with the Norway spruce forest is especially focused on the methods of laboratory spectroscopy. The assessment of Norway spruce stands on a regional and a global scales requires detailed knowledge of their spectral properties at the level of needles and shoots in the beginning, but ground research is very time-demanding. Open spectral libraries could help to get more ground-truth data for subsequent analysis of tree species in forests ecosystems. However, the problem may arise with the comparability of spectra taken by different devices. The present thesis focuses on a comparability of spectra measured by a field spectroradiometer coupled with plant contact probe and/or two integrating spheres (Paper 3) and proves the significant differences in spruce needle spectra measured by the contact probe and integrating sphere, spectra of...
512

Skillnadernas begränsning : En studie i skillnadernas betydelse för fördjupat svenskt-norskt militärt samarbete / The limitation of differences : a study of the significance of differences for deeper Swedish-Norwegian military cooperation

Christoffersson, Gustav, Sundelin, Niklas January 2020 (has links)
Den säkerhetspolitiska situationen i Norden var under kalla kriget låst i kampen mellan öst och väst. Detta innebar att respektive lands möjligheter att fritt välja säkerhetsstrategi var begränsad. Först efter slutet på kalla kriget öppnade sig denna möjlighet och länderna kunde även se sig om efter nya samarbeten och partners. Nya säkerhetsstrategier utarbetas i Sverige och Norge där det internationella åtagandet stärks och nya samarbeten utvecklas med bland annat det nordiska försvarssamarbetet. När Ryssland i och med sitt agerande i Georgien och Ukraina återigen börjar utgöra ett potentiellt hot börjar det territoriella försvaret hamna i fokus igen. Den nya säkerhetspolitiska situationen leder till ett militärt samarbete mellan Sverige och Finland som bland annat involverar försvarsplanering för skyddandet av det andra landets territorium. Men ett sådant samarbete uppstår inte mellan Sverige och Norge. Syftet med denna studie är att undersöka och beskriva likheter och skillnader i svensk- och norsk säkerhetsstrategi sedan förändringen i omvärldsläget 2008 och vidare beskriva eventuella möjligheter för utvidgade försvars- och militära samarbeten mellan Sverige och Norge, liknande det som finns mellan Sverige och Finland. Studien använder sig av kvalitativ textanalys applicerat på norska och svenska försvarsbeslut, propositioner eller underlag inför dessa. För att kunna svara på studiens syfte och frågeställningar används två olika teorier, en per frågeställning, som appliceras på textanalysens resultat. Studiens viktigaste resultat består i att de slående likheterna mellan svensk och norsk säkerhetsstrategi beror på den gemensamma strategiska miljö som länderna befinner sig i samt att hoten i den förändrade omvärlden tolkas likvärdigt. De största likheterna mellan de två ländernas utformade säkerhetsstrategier finns i de säkerhetspolitiska målen samt de tillgången till nationella medel och resurser. Den största skillnaden mellan länderna rör vald metod att genomföra sin strategi på, där Norge för en tydlig allianspolitik och bygger sitt nationella försvar kring Nato medan Sverige väljer att stå militärt alliansfritt och samarbeta genom bilaterala avtal. Denna skillnad är också den faktor som starkast negativt påverkar förutsättningarna för ett mer utvecklat militärt samarbete länderna emellan. Utöver frågan kring Nato finns det goda möjligheter för vidare militära samarbeten främst genom gemensamma förband för internationella operationer. / During the Cold War, the security situation in the Nordic countries was fixed in the battle between the East and the West. This meant that each country's ability to freely choose a security strategy was limited. Only after the end of the Cold War did this opportunity emerge and the countries could look for new partnerships. New security strategies were developed in Sweden and Norway, where the international commitment was strengthened and new collaborations were being developed, for example the Nordic defence cooperation. When Russia begun to pose a potential threat with its actions in Georgia and Ukraine, territorial defence rose in priority. The new security situation leads to enhanced military cooperation between Sweden and Finland, which involves, among other things, military planning for the protection of the other country's territory. But no such cooperation develops between Sweden and Norway. The purpose of this study is to investigate and define similarities and differences in the Swedish and Norwegian security strategies since the change in the external situation in 2008 and further describe possible opportunities for enhanced defence and military cooperations between Sweden and Norway, similar to the ones existing between Sweden and Finland. The study uses a qualitative text analysis applied to Norwegian and Swedish defence decisions, acts or reports. To be able to answer the study's purpose and questions, two different theories are being used, one per each question, which is applied to the results of the text analysis. The most significant result of this study is that the most prominent similarities in Swedish and Norwegian security strategies are results of a shared view of the strategic environment and new threats from changes in the external situation is interpreted likewise in both nations. The most notable similarities are found in the stated strategic ends for each country’s security strategy and the national means in assets and capabilities they both possess. The biggest difference between the two are in which ways they operate in the strategic environment, where Norway has chosen NATO as the foundation of their national defence and Sweden stands as non-allied military state depending on bilateral agreements for cooperation. This difference is also the most vital factor negatively effecting the possibilities for enhanced military cooperation between the two countries. Apart from the issue surrounding NATO there are relatively good possibilities for further military cooperation, primarily thru joint military units for international operations.
513

Využití obrazové spektroskopie pro monitoring zátěže vegetace polutanty obsaženými v půdním substrátu Sokolovské hnědouhelné pánve / Application of imaging spectroscopy in monitoring of vegetation stress caused by soil pollutants in the Sokolov lignite basin

Mišurec, Jan January 2018 (has links)
Forests can be considered as one of the most important Earth's ecosystems not only because of oxygen production and carbon sequestration via photosynthesis, but also as a source of many natural resources (such as wood) and as a habitat of many specific plants and animals. Monitoring of forest health status is thus crucial activity for keeping all production and ecosystem functions of forests. The main aim of the thesis is development of an alternative approach for forest health status based on airborne hyperspectral data (HyMap) analysis supported by field sampling. The proposed approach tries to use similar vegetation parameters which are used in case of the current methods of forest health status assessment based on field inspections. It is believed that importance of such new methods will significantly increase in the time when the planned satellite hyperspectral missions (e.g. EnMap) will move into operational phase. The developed forest health monitoring approach is practically demonstrated on mature Norway spruce (Picea abies L. Karst) forests of the Sokolov lignite basin which were affected by long-term coal mining and heavy industry and therefore high variability of forest health status was assumed in this case. Two leaf level radiative transfer models were used for simulating spectral...
514

The British North Sea: The Importance Of And Factors Affecting Tax Revenue From Oil Production

Hill, Mark 10 February 2004 (has links) (PDF)
The oil industry is the richest and most influential industry in the world. The industry has moved the fates of nations. Oil is required to fight wars and exert power, and the restriction of this energy source is paramount to the restriction of movement, control, and in the end, power. Management of this resource and the tax revenue it generates are of serious strategic importance, both domestically and internationally. Understanding the results of taxation for this important commodity is important to international relations as well. The tax system affects tax revenue, government actions, oil company actions, and the oil supply itself. Each of these is important to international relations.
515

Surface characterisation of thermally modified spruce wood and influence of water vapour sorption

Källbom, Susanna January 2015 (has links)
Today there is growing interest within the construction sector to increase the proportion of biobased building materials made from renewable resources. By-products or residuals from wood processing could in this case be valuable resources for manufacturing new types of biocomposites. An important research question related to wood-based biocomposites is how to characterise molecular interactions between the different components in the composite. The hygroscopic character of wood and its water sorption properties are also crucial. Thermal modification (or heat treatment) of wood results in a number of enhanced properties such as reduced hygroscopicity and improved dimensional stability as well as increased resistance to microbiological decay. In this thesis, surface characteristics of thermally modified wood components (often called wood fibres or particles) and influencing effects from moisture sorption have been analysed using a number of material characterisation techniques. The aim is to increase the understanding in how to design efficient material combinations for the use of such wood components in biocomposites. The specific objective was to study surface energy characteristics of thermally modified spruce (Picea abies Karst.) under influences of water vapour sorption. An effort was also made to establish a link between surface energy and surface chemical composition. The surface energy of both thermally modified and unmodified wood components were studied at different surface coverages using inverse gas chromatography (IGC), providing information about the heterogeneity of the surface energy. The water vapour sorption behaviour of the wood components was studied using the dynamic vapour sorption (DVS) method, and their surface chemical composition was studied by means of X-ray photoelectron spectroscopy (XPS). Additionally, the morphology of the wood components was studied with scanning electron microscopy (SEM). The IGC analysis indicated a more heterogeneous surface energy character of the thermally modified wood compared with the unmodified wood. An increase of the dispersive surface energy due to exposure to an increased relative humidity (RH) from 0% to 75% RH at 30 ˚C was also indicated for the modified samples. The DVS analysis indicated an increase in equilibrium moisture content (EMC) in adsorption due to the exposure to 75% RH. Furthermore, the XPS results indicated a decrease of extractable and a relative increase of non-extractable compounds due to the exposure, valid for both the modified and the unmodified wood. The property changes due to the increased RH condition and also due to the thermal modification are suggested to be related to alterations in the amount of accessible hydroxyl groups in the wood surface. Recommendations for future work and implications of the results could be related to knowledge-based tailoring of new compatible and durable material combinations, for example when using thermally modified wood components in new types of biocomposites for outdoor applications. / <p>Forskningsfinansiärer och strategiska forskningsprojekt:</p><p>Nils och Dorthi Troëdssons forskningsfond (Projektnr 793/12 Hydro-termo-mekanisk modifiering av trä).</p><p> KTH Royal Institute of Technology.</p><p> COST Action FP0904.</p><p> KK-Stiftelsen.</p><p>Stiftelsen för strategiskt forskning (SSF). QC 20150908</p>
516

Enabling socio-technical transitions – electric vehicles and high voltage electricity grids as focal points of low emission futures

Albrecht, Martin January 2017 (has links)
Today humankind is facing numerous sustainability challenges that require us to question CO2 intensive practices like those present in the transport and energy sector. To meet those challenges, many countries have adopted ambitious climate targets. Achieving such targets requires an understanding of the wider socio-technical context of transitions. The aim of this licentiate thesis is therefore to analyse such socio-technical transitions towards low-emission futures enabled by the electrification of passenger cars and high voltage grid development. A combination of different transitions theories (for ex. Multi-level perspective and Technological innovation systems) and institutional theory has been used. To reach the aim paper I analyses the climate impacts of electric vehicles (EVs) and policy measures to achieve a breakthrough scenario for EVs. The results show that a mixture of short and long term policies are needed that take into account the technology development stage and behavioural aspects of EV adopters. Paper II addresses the need to include the high voltage transmission grid and its planning procedures as a central part of debates on transitions. Therefore the opportunities, challenges and reasons for conflict in the established regime are studied. The results show that in order to achieve a sustainable grid development regime, it is necessary to spend time on achieving legitimacy and social sustainability. The third paper uses semi-structured expert interviews and focuses on innovation dynamics for EV adoption. By focusing on dynamics instead of single policy measures, it is possible to grasp interactions within a niche, but also in between a niche, regime and landscape. The results show that strong initial technology legitimacy was needed to start substantial innovation dynamics. This could be further strengthened with a strong and broad coalition of actors. Both those factors led, if present, to an improved variety and match of policy instruments. As such this thesis has shown that transitions are not just about technology or policy instruments as such but about the dynamics and processes needed to enable them. This can be relevant in other transitions that otherwise may underestimate the importance of these components. / <p>QC 20170512</p> / Norstrat
517

Environmental factors affecting European spruce bark beetle (Ips typographus) outbreaks in Sweden : Linking AI-detected dead spruce, soil moisture, nature protection and bark beetle outbreak (Ips typographus) in Sweden / Miljöfaktorer som påverkar utbrott av granbarkborre (Ips typographus) i Sverige : Sammankoppla AI-detekterade döda granar, markfuktighet, naturvård och granbarkborreutbrott (Ips typographus) i Sverige

Hessle, Petter January 2023 (has links)
Norway spruce (Picea abies) is a vital tree species in Sweden's extensive forested landscape. However, the planting of spruce beyond its natural range has made it vulnerable to pests like the spruce bark beetle (Ips typographus), which has caused substantial damage to Swedish forests. With the effects of global warming and climate change becoming increasingly apparent, understanding the factors influencing spruce mortality is crucial for effective forest management. This study aimed to investigate the impact of soil moisture and tree size on the susceptibility of Norway spruce to spruce bark beetle attacks. Using a combination of an Artificial Intelligence (AI) program detecting dead spruce trees and soil moisture data from the Swedish University of Agricultural Sciences (SLU), areas in Stockholm County with dead spruce trees were identified. Spatial analysis using Geographic Information System (GIS) tools and a field survey were conducted to evaluate the hypotheses: H1: Spruce mortality will be higher in areas occurring within mesic soil moisture class (1) than within mesic-moist soil moisture class (2) and moist-wet soil moisture class (3). H2: Large diameter spruce trees will have a higher mortality rate from spruce bark beetle than smaller diameter trees. H3: Spruce mortality will be higher in areas located inside nature reserves. The results confirmed that spruce mortality was higher in areas with dryer soil, Additionally, larger diameter spruce trees exhibited higher mortality rates from spruce bark beetle attacks than smaller trees. Contrary to the initial hypothesis, the study did not find a higher spruce mortality rate in areas located outside nature reserves. The conclusion of this study is that both tree size and soil moisture affect the Norway spruce’s ability to defend itself from spruce bark beetle attacks, but it does not confirm that spruce trees inside nature reserves have a greater mortality rate due to bark beetle attacks than the surrounding areas. The study has contributed to a better understanding of how spruce bark beetles choose trees. It has also provided more knowledge and validation of the Swedish Forest Agency AI program, which is trained to find dead spruce trees. The fact that this is a working tool opens a lot of possibilities for further use. The knowledge of soil moisture’s effect on spruce survival will also help forest managers make better choices when selecting areas for planting spruce. This will also benefit both the forest owners economically and help suppress the spread of spruce bark beetle. / Gran (Picea abies) är en viktig trädart i Sveriges omfattande skogslandskap. Dock har plantering av gran utanför dess naturliga utbredningsområde gjort den sårbar för skadedjur så som Granbarkborre (Ips typographus), vilket har orsakat betydande skador på svenska skogar. Med effekterna av klimatförändringar är det alltmer viktigt att förstå vilka faktorer som påverkar granens sårbarhet mot granbarkborren för en effektiv skogsförvaltning. Denna studie syftade till att undersöka påverkan av markfuktighet och trädstorlek. Genom att använda en kombination av ett artificiellt intelligensprogram (AI) som identifierar döda granar och markfuktighetsdata från Sveriges lantbruksuniversitet (SLU), identifierades områden i Stockholms län där det fanns döda granar. En spatial analys med hjälp av geografiska informationssystem (GIS) och en fältundersökning genomfördes för att utvärdera hypoteserna: H1: Granens dödlighet kommer att vara högre i områden med torr-frisk mark (1) jämfört med områden med frisk-fuktig markfuktighet (2) och fuktig-våt markfuktighet (3). H2: Granar med större diameter kommer att ha en högre dödlighetsgrad från granbarkborrsangrepp än granar med mindre diameter. H3: Granens dödlighet kommer att vara högre i områden i naturreservat än utanför. Resultaten bekräftade att granens dödlighet var högre i torrare områden. Dessutom uppvisade granar med större diameter högre dödlighetsgrad från garnbarkborreangrepp än mindre träd. Resultatet kunde inte bekräfta hypotes H3, man fann inte en högre dödlighetsgrad hos gran i områden inom naturreservat. Slutsatsen av denna studie är att både trädstorlek och markfuktighet påverkar granens förmåga att försvara sig mot granbarkborreangrepp, men den bekräftar inte att naturreservat har en påverkan på granens dödlighet till följd av granbarkborreangrepp än omgivande områden. Studien har bidragit till en bättre förståelse för hur granbarkborren väljer granar. Den har också tillfört mer kunskap och bekräftat att Skogsstyrelsens AI-program hittar döda granar. Att AI-programmet är ett fungerande verktyg öppnar upp många möjligheter för framtida användningsområden. Kunskapen om markfuktighetens effekt på granens överlevnad kommer också att kunna hjälpa skogsförvaltare att fatta bättre beslut vid val av områden för plantering av gran. Detta kommer att gynna både skogsägarna ekonomiskt och bidra till att minska antalet granbarkborreangrepp.
518

Reduce, Reuse, Recycle – Research: Sustainable Scene Design for a Production of Henrik Ibsen’s <i>An Enemy Of The People</i>

Quinlan, Joshua Mortimer 14 September 2016 (has links)
No description available.
519

Gute Nation oder Europa?

Hille, Jochen 09 December 2005 (has links)
Norwegen und die Schweiz sind keine EU-Mitgliedstaaten, weil die Bevölkerungen die Integration mehrheitlich in Referenden ablehnte. Die enorme Mobilisierung und Emotionalisierung in den nationalen Integrationsdebatten kann weder durch ökonomische noch durch politische Umstände hinreichend erklärt werden, zumal die Eliten beider Länder mehrheitlich die Integration unterstützen. Die Hauptmobilisierungsressource von Euroskeptikern liegt vielmehr darin, tief verwurzelte nationale Selbst- und Fremdbilder zu reaktivieren. Diese Diskursanalyse beschreibt vergleichend, auf welche Art und Weise die größten euroskeptischen Akteure der Schweiz und Norwegens diesen Rückgriff auf das Nationale in Integrationsdebatten herstellen. Gefragt wird, wie die „Aktion für eine Unabhängige und Neutrale Schweiz“ (AUNS) und die eng mit ihr verbundene „Schweizerische Volkspartei“ (SVP) einerseits, und die norwegische Bewegung „Nein zur EU“ (norwegisch: Nei Til EU) andererseits, ihren Integrationswiderstand mittels nationaler Narrationen und Bildersprachen als sinnvoll darstellen. Hierzu werden umfangreiche euroskeptische Bild- und Textquellen referiert und gedeutet. Damit wird ein Beitrag zur Forschung über das Selbstverständnis, die Denkweise, die Rhetorik und das Tugendsystem anti-integratorischer Bewegungen geleistet. Denn Euroskeptiker verstehen sich primär als Verteidiger der guten nationalen Gemeinschaft. Diese Gemeinschaft und dessen Nationalstaat beschreiben sie als wärmer, natürlicher, näher, gerechter, effizienter, friedlicher und demokratischer als das integrierte Europa, welches als ferner, kalter, bürokratischer Superstaat EU dargestellt wird. / Norway and Switzerland are not member states of the EU, since the majority of the people rejected integration in several referenda. The emotionality and the enormous mobilisation in national debates on integration cannot sufficiently be explained by economic and political reasons, since the majority of the elites are supporting integration. Instead, the main resource of mobilisation for Eurosceptics lies in reactivating deeply rooted descriptions of national self and other. For carving out these collective images, this discourse-analysis compares how the major Eurosceptical actors of Switzerland, the “Action for an Independent and Neutral Switzerland” (AUNS) together with the tightly connected “Swiss People’s Party” (SVP), on one hand, and the Norwegian movement “No To EU” (NEI TIL EU), on the other hand, describe their actions as meaningful in their iconography and narrations. In doing so, the study refers to and interprets extensive material from Eurosceptical actors and contributes to the understanding of Eurosceptical self-perception, ways of thinking, rhetoric and virtue system. Here Eurosceptics perceive themselves mainly as defenders of the national community and its nation-state, which are regarded as warm, natural, close, justified, efficient, peaceful and democratic, while Europe is perceived as the cold, distant, bureaucratic superstate EU.
520

Raumzeitliche Dynamik der Parameter des Energie-, Wasser und Spurengashaushalts nach Kleinkahlschlag / Spatiotemporal dynamics of the paramter of energy, water and trace gas balance after clear cut

Fröhlich, Daniel 05 June 2009 (has links)
No description available.

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