<p>Magnetic Resonance Imaging is an established technology for both imaging and</p><p>functional studies in clinical and research environments. The field is still very</p><p>research intense. Two major research areas are acquisition time and signal quality.</p><p>The last decade has provided tools for more efficient possibilities of trading these</p><p>factors against each other through parallel imaging.</p><p>In this thesis one parallel imaging method, Sensitivity Encoding for fast</p><p>MRI (SENSE) is examined. An alternative solution CCASENSE is developed.</p><p>CCASENSE reduces the acquisition time by estimating the sensitivity maps required</p><p>for SENSE to work instead of running a reference scan. The estimation</p><p>process is done by Blind Source Separation through Canonical Correlation Analysis.</p><p>It is shown that CCASENSE appears to estimate the sensitivity maps better</p><p>than ICASENSE which is a similar algorithm.</p>

The thesis presents an investigation of the potential of measuring plant condition from hyperspectral reflectance data. To do this, some linear methods for embedding the high dimensional hyperspectral data and to perform regression to a plant condition space have been compared. A preprocessing step that aims at normalized illumination intensity in the hyperspectral images has been conducted and some different methods for this purpose have also been compared.A large scale experiment has been conducted where tobacco plants have been grown and treated differently with respect to watering and nutrition. The treatment of the plants has served as ground truth for the plant condition. Four sets of plants have been grown one week apart and the plants have been measured at different ages up to the age of about five weeks. The thesis concludes that there is a relationship between plant treatment and their leaves' spectral reflectance, but the treatment has to be somewhat extreme for enabling a useful treatment approximation from the spectrum. CCA has been the proposed method for calculation of the hyperspectral basis that is used to embed the hyperspectral data to the plant condition (treatment) space. A preprocessing method that uses a weighted normalization of the spectrums for illumination intensity normalization is concluded to be the most powerful of the compared methods.

Magnetic Resonance Imaging is an established technology for both imaging and functional studies in clinical and research environments. The field is still very research intense. Two major research areas are acquisition time and signal quality. The last decade has provided tools for more efficient possibilities of trading these factors against each other through parallel imaging. In this thesis one parallel imaging method, Sensitivity Encoding for fast MRI (SENSE) is examined. An alternative solution CCASENSE is developed. CCASENSE reduces the acquisition time by estimating the sensitivity maps required for SENSE to work instead of running a reference scan. The estimation process is done by Blind Source Separation through Canonical Correlation Analysis. It is shown that CCASENSE appears to estimate the sensitivity maps better than ICASENSE which is a similar algorithm.

Functional Magnetic Resonance Imaging (fMRI) is a neuroimaging technique used to study brain functionality to enhance our understanding of the brain. This technique is based on MRI, a painless, noninvasive image acquisition method without harmful radiation. Small local blood oxygenation changes which are reflected as small intensity changes in the MR images are utilized to locate the active brain areas. Radio frequency pulses and a strong static magnetic field are used to measure the correlation between the physical changes in the brain and the mental functioning during the performance of cognitive tasks. This master thesis presents approaches for the analysis of fMRI data. The constrained Canonical Correlation Analysis (CCA) which is able to exploit the spatio-temporal nature of an active area is presented and tested on real human fMRI data. The actual distribution of active brain voxels is not known in the case of real human data. To evaluate the performance of the diagnostic algorithms applied to real human data, a modified Receiver Operating Characteristics (modified ROC) which deals with this lack of knowledge is presented. The tests on real human data reveal the better detection efficiency with the constrained CCA algorithm. A second aim of this thesis was to implement the promising technique of constrained CCA into the software environment SPM. To implement the constrained CCA algorithms into the fMRI part of SPM2, a toolbox containing Matlab functions has been programmed for the further use by neurological scientists. The new SPM functionalities to exploit the spatial extent of the active regions with CCA are presented and tested.

In this study, the hydrology and physical, chemical and biological variables of a shallow lake system including the Lakes Mogan and Eymir between 1997-2005 were evaluated. In Lake Eymir, a biomanipulation study was conducted between August, 1998 &ndash / December, 1999. Upon biomanipulation, Lake Eymir shifted to clearwater state with submerged vegetation domination during 2000-2003. However, in 2004, the lake shifted back to algae-dominated turbid state since the buffer mechanisms provided by submerged plants were absent. In the summer of 2005, fish kills were observed due to algal bloom. However, due to increasing hydraulic residence time in the lake, internal processes became more important for nutrients. Lake Mogan faces seasonal and interannual water level fluctuations. During the low water levels experienced in 2001 and 2005, which coincided with the high hydraulic residence times, the in-lake phosphorus amount was controlled by internal processes rather than external loading. Moreover, results revealed that hydrology and submerged plants were important in the ecology of Lake Mogan. Furthermore, the relationship between the phytoplankton, zooplankton and the environment in Lakes Eymir and Mogan, which was predicted via Canonical Corresponding Analysis, revealed that nutrients and water transparency were both important for plankton communities. Both the top-down and bottom up effects were valid in Lake Eymir, while only the bottom-up effect and submerged plants were important for Lake Mogan. Finally, the present study provided a good example for the submerged plant dominated clearwater state triggered by biomanipulation, and the impact of hydrology on the ecology of shallow lakes.

This dissertation explores the application of the techniques of mathematical finance to the achievement of investment targets and financial stability. It contains three self-contained but broadly related essays. Sharpe et al. proposed the idea of having an expected utility maximizer choose a probability distribution for future wealth as an input to her investment problem rather than a utility function. They developed the Distribution Builder as one way to elicit such a distribution. In a single-period model, they then showed how this desired distribution for terminal wealth can be used to infer the investor's risk preferences. In the first essay, we adapt their idea, namely that a desired distribution for future wealth is an alternative input attribute for investment decisions, to continuous time. In a variety of scenarios, we show how the investor's desired distribution, combined with her initial wealth and market-related input, can be used to determine the feasibility of her distribution, her implied risk preferences, and her optimal policies throughout her investment horizon. We then provide several examples. In the second essay, we consider an investor who must a priori liquidate a large position in a primary risky asset whose price is influenced by the investor's liquidation strategy. Liquidation must be complete by a terminal time T, and the investor can hedge the market risk involved with liquidation over time by investing in a liquid proxy asset that is correlated with the primary asset. We show that the optimal strategies for an investor with constant absolute risk aversion are deterministic and we find them explicitly using calculus of variations. We then analyze the strategies and determine the investor's indifference price. In the third essay, we use contingent claims analysis to study several aggregate distance-to-default measures of the S&P Financial Select Sector Index during the years leading up to and including the recent financial crisis of 2007-2009. We uncover mathematical errors in the literature concerning one of these measures, portfolio distance-to-default, and propose an alternative measure that we show has similar conceptual and in-sample econometric properties. We then compare the performance of the aggregate distance-to-default measures to other common risk indicators. / text

End products of society (e.g. sewage sludge and incineration ashes) can be used as indicators of the use of chemicals in consumer goods. Through upstream work the sources of substances released from goods may be identified before the emissions reach the end products. This thesis is a result of five studies, of which four were conducted using substance flow analyses (SFA) for silver (Ag), bismuth (Bi) and copper (Cu) reaching sewage sludge. The fifth is an SFA that explores the implications of the presence of As (from CCA-treated wood) in ashes. These studies helped fulfil the specific and overall aims of the thesis; to contribute to the general knowledge on diffuse emissions reflected in end products, by examining emissions of some heavy metals from various societal goods and the implications for end products, in this case sewage sludge and, to some extent, ashes. The results from the studies, of which four had Stockholm as a study object, show the urban flows and accumulated amounts (stocks) of the heavy metals. The largest sources of the metals Ag, Bi and Cu in sewage sludge were identified to be textiles (Ag), cosmetics (Bi) and brake linings (Cu). For As (in CCA-treated wood) and Cu updated SFAs were performed and compared with earlier studies in order to follow the development and changes in flows over time. The current use of the heavy metals studied can also be seen as a loss of resources, and as the metals should ideally be recovered as a part of a circular economy, urban and landfill mining as well as recycling are alternatives that need further exploring. The legislation of chemicals in consumer goods was identified as an important step in handling corresponding diffuse emissions.

Nas mais diversas atividades industriais hoje existentes está presente a problemática dos resíduos gerados e seu gerenciamento. Os efluentes líquidos são uma grande fonte de poluição dos recursos hídricos, sendo necessário o controle das condições de seu descarte. Para efluentes contendo poluentes orgânicos uma das alternativas de tratamento que vem sendo muito utilizada é o uso de Processos Oxidativos Avançados - POA’s. Esses processos se baseiam na geração de radicais livres, principalmente o radical hidroxila (HO.), que possui alto poder oxidante e pode promover a degradação de vários compostos poluentes eficientemente. Esses processos têm obtido grande atenção devido ao aumento da complexidade e dificuldade no tratamento de águas residuárias, o que tem sido motivo para a busca de novas metodologias visando a remediação desses rejeitos. Diante disso, o presente trabalho tem por objetivo estudar os processos (POA’s), para a degradação da matéria orgânica em efluente oriundo da descontaminação de madeira tratada com Arseniato de Cobre Cromatado – CCA. Este efluente é gerado através de extração ácida em ciclos de madeira tratada com CCA que foram utilizados como postes tanto de eletricidade como de telefonia. O efluente gerado na extração ácida foi caracterizado através dos parâmetros de pH, Condutividade, Demanda Química de Oxigênio, Carbono Orgânico Dissolvido, Sólidos totais e metais. Após caracterização, o efluente foi submetido aos processos oxidativos avançados de Fotólise, Fotocatálise heterogênea, Eletrólise e Fotoeletrooxidação, a fim de degradar a matéria orgânica. Depois de realizados os processos, o efluente foi caracterizado novamente com os mesmos parâmetros. Pode-se concluir que todos os processos utilizados alcançaram resultados positivos, degradaram a matéria orgânica, mas o processo que obteve melhor rendimento de degradação foi o de Eletrólise que degradou 68% da matéria orgânica presente no efluente. / In the most diverse industrial activities exist today is present the problem of waste generated and its management. Liquid effluents are a major source of pollution of water resources, requiring the control of the disposal conditions. For wastewater containing organic pollutants the use of Advanced Oxidation Processes - POA's has been widely used. These processes are based on the generation of free radicals, especially the hydroxyl radical (HO.), which has high oxidizing power and can promote the degradation of several polluting compounds efficiently. These processes have achieved great attention due to the increasing complexity and difficulty in the treatment of residual waters, which has been the reason for the search of new methods for remediation of these wastes. Therefore, this paper aims to study these processes (POA's) for the degradation of organic matter in the effluent coming from the decontamination of wood treated with CCA - chromated copper arsenate. This effluent is generated by cycles of acid extraction of wood treated with CCA which were used as both telephone and electricity poles. The effluent generated by the acid extraction was characterized by the parameters pH, conductivity, chemical oxygen demand, dissolved organic carbon and metals. After characterization, the effluent was subjected to advanced oxidation processes photolysis, heterogeneous photocatalysis, Electrolysis and photoelectrooxidation (which are the three processes together) in order to degrade organic matter. After the effluent treatment, the solution was again characterized by the same parameters. It can be concluded that all the processes used have achieved positive results, degradeding organic matter, but the process that showed the best performance degradation was the electrolysis with 68% less organic matter.

Nas mais diversas atividades industriais hoje existentes está presente a problemática dos resíduos gerados e seu gerenciamento. Os efluentes líquidos são uma grande fonte de poluição dos recursos hídricos, sendo necessário o controle das condições de seu descarte. Para efluentes contendo poluentes orgânicos uma das alternativas de tratamento que vem sendo muito utilizada é o uso de Processos Oxidativos Avançados - POA’s. Esses processos se baseiam na geração de radicais livres, principalmente o radical hidroxila (HO.), que possui alto poder oxidante e pode promover a degradação de vários compostos poluentes eficientemente. Esses processos têm obtido grande atenção devido ao aumento da complexidade e dificuldade no tratamento de águas residuárias, o que tem sido motivo para a busca de novas metodologias visando a remediação desses rejeitos. Diante disso, o presente trabalho tem por objetivo estudar os processos (POA’s), para a degradação da matéria orgânica em efluente oriundo da descontaminação de madeira tratada com Arseniato de Cobre Cromatado – CCA. Este efluente é gerado através de extração ácida em ciclos de madeira tratada com CCA que foram utilizados como postes tanto de eletricidade como de telefonia. O efluente gerado na extração ácida foi caracterizado através dos parâmetros de pH, Condutividade, Demanda Química de Oxigênio, Carbono Orgânico Dissolvido, Sólidos totais e metais. Após caracterização, o efluente foi submetido aos processos oxidativos avançados de Fotólise, Fotocatálise heterogênea, Eletrólise e Fotoeletrooxidação, a fim de degradar a matéria orgânica. Depois de realizados os processos, o efluente foi caracterizado novamente com os mesmos parâmetros. Pode-se concluir que todos os processos utilizados alcançaram resultados positivos, degradaram a matéria orgânica, mas o processo que obteve melhor rendimento de degradação foi o de Eletrólise que degradou 68% da matéria orgânica presente no efluente. / In the most diverse industrial activities exist today is present the problem of waste generated and its management. Liquid effluents are a major source of pollution of water resources, requiring the control of the disposal conditions. For wastewater containing organic pollutants the use of Advanced Oxidation Processes - POA's has been widely used. These processes are based on the generation of free radicals, especially the hydroxyl radical (HO.), which has high oxidizing power and can promote the degradation of several polluting compounds efficiently. These processes have achieved great attention due to the increasing complexity and difficulty in the treatment of residual waters, which has been the reason for the search of new methods for remediation of these wastes. Therefore, this paper aims to study these processes (POA's) for the degradation of organic matter in the effluent coming from the decontamination of wood treated with CCA - chromated copper arsenate. This effluent is generated by cycles of acid extraction of wood treated with CCA which were used as both telephone and electricity poles. The effluent generated by the acid extraction was characterized by the parameters pH, conductivity, chemical oxygen demand, dissolved organic carbon and metals. After characterization, the effluent was subjected to advanced oxidation processes photolysis, heterogeneous photocatalysis, Electrolysis and photoelectrooxidation (which are the three processes together) in order to degrade organic matter. After the effluent treatment, the solution was again characterized by the same parameters. It can be concluded that all the processes used have achieved positive results, degradeding organic matter, but the process that showed the best performance degradation was the electrolysis with 68% less organic matter.

MIFO (a Method for Investigation of Polluted Areas) is a Swedish investigationtechnique for polluted areas which is produced by the Swedish environmentalprotection agency. The purpose with MIFO is to standardize and simplify theevaluation of the situation in the environment in terms of the extent of pollution andit’s hazards and dispersal rate. A MIFO – analysis should lay the groundwork forfurther investigations and actions. The analysis gives a priority system where themore contaminated areas are processed with higher priority than areas with lesspollution or risks.The purpose with this report is to comleate a MIFO – 2 – analysis of Gimowoodpreservation factory in Östhammar municipality, Sweden. Gimowoodpreservation factory was during the 30’s to 50’s contaminated by the woodpreservative CCA (Copper, Chromium, Arsenic)The area has since then been investigated several times and remediated once.Copper, chromium and arsenic are breafly described in the report in terms of theireffects on humans and the environment and their general behaviour in water andsoil.Arsenic is a dangerous substance and is considered poisonous for humans and theenvironment. Copper and chromium are not considered as to be as hazardous.The amounts of the three substances in the water around Gimo are considered amoderate and low risk. The amounts of arsenic are in some places in the soil areabove the guideline values. The risk of spreading of the pollution is however low, andtherefore the result of the MIFO – analysis of Gimo woodpreservation factory isevaluated as “3 – moderate risk”. / MIFO (Metodik för Inventering av Förorenade Områden) är en nationell inventeringsmetod för förorenad mark framställd av Naturvårdsverket. Syftet med metoden är att få en gemensam nationell metod att enkelt och enhetligt bedöma miljökvalitén i olika områden i Sverige med avseende på föroreningars omfattning, samt skade- och spridningsriskerna dessa medför. En MIFO-analys skall ligga som grund för fortsatta undersökningar och eventuella åtgärder inom ett förorenat område. MIFO leder till ett prioriteringssystem där de mer kontaminerade områdena åtgärdas med högre prioritet än områden med lägre föroreningshalt eller spridningsrisker. Syftet med denna rapport är att genomföra en MIFO – fas 2 analys över Gimo träimpregnering, Östhammar kommun. Gimo träimpregnering kontaminerades under 30-50-talet med impregneringsmedlet CCA, ett impregneringsmedel innehållande koppar, krom och arsenik. Området har sedan slutet av 80-talet undersökts i flera studier samt sanerats. Koppar krom och arsenik beskrivs kort i rapporten med avseende på dess skadeverkan för människa och miljö, samt dess generella beteende i mark och vatten. Arsenik är ett skadligt ämne och är mycket farligt för människor miljön. Koppar och krom räknas inte lika miljöskadliga. Halterna av de tre ämnena ligger inom måttliga nivåer i grundvattnet kring Gimo, men riktvärden för arsenik överskrids till viss mån i marken. Spridningsrisken är dock låg i området och detta medför att MIFO-analysen av Gimo träimpregnering, gav resultatet ”Riskklass 3, måttlig risk”.