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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.
31

the Wanderer

2013 January 1900 (has links)
A reflective essay to accompany the thesis exhibition, the Wanderer, installed in the Gordon Snelgrove Gallery, 2013. An exploration of the questions and concepts informing the process of developing and refining the visual vocabulary of my practice. Images of women, topographical maps, floral imagery and astronomical maps provide the vocabulary of the language and syntax that I am developing to enunciate the interrelationships between the construction of self and lived experience, with concepts of identity, body and gesture, history and place.
32

Formulação teórica dos fundamentos da otimização global topográfica com análise de desempenho e aplicações à estabilidade de fases de misturas termodinâmicas / Theoretical formulation of fundamentals of topographical global optimization method with performance analysis and applications to the phase stability of thermodynamic mixtures

Marroni de Sá Rêgo 23 February 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Métodos de otimização que utilizam condições de otimalidade de primeira e/ou segunda ordem são conhecidos por serem eficientes. Comumente, esses métodos iterativos são desenvolvidos e analisados à luz da análise matemática do espaço euclidiano n-dimensional, cuja natureza é de caráter local. Consequentemente, esses métodos levam a algoritmos iterativos que executam apenas as buscas locais. Assim, a aplicação de tais algoritmos para o cálculo de minimizadores globais de uma função não linear,especialmente não-convexas e multimodais, depende fortemente da localização dos pontos de partida. O método de Otimização Global Topográfico é um algoritmo de agrupamento, que utiliza uma abordagem baseada em conceitos elementares da teoria dos grafos, a fim de gerar bons pontos de partida para os métodos de busca local, a partir de pontos distribuídos de modo uniforme no interior da região viável. Este trabalho tem dois objetivos. O primeiro é realizar uma nova abordagem sobre método de Otimização Global Topográfica, onde, pela primeira vez, seus fundamentos são formalmente descritos e suas propriedades básicas são matematicamente comprovadas. Neste contexto, propõe-se uma fórmula semi-empírica para calcular o parâmetro chave deste algoritmo de agrupamento, e, usando um método robusto e eficiente de direções viáveis por pontos-interiores, estendemos o uso do método de Otimização Global Topográfica a problemas com restrições de desigualdade. O segundo objetivo é a aplicação deste método para a análise de estabilidade de fase em misturas termodinâmicas,o qual consiste em determinar se uma dada mistura se apresenta em uma ou mais fases. A solução deste problema de otimização global é necessária para o cálculo do equilíbrio de fases, que é um problema de grande importância em processos da engenharia, como, por exemplo, na separação por destilação, em processos de extração e simulação da recuperação terciária de petróleo, entre outros. Além disso, afim de ter uma avaliação inicial do potencial dessa técnica, primeiro vamos resolver 70 problemas testes, e então comparar o desempenho do método proposto aqui com o solver MIDACO, um poderoso software recentemente introduzido no campo da otimização global. / Optimization methods that use optimality conditions of first and/or second order are known to be efficient. Commonly, such iterative methods are developed and analyzed in the light of knowledge concerning the mathematical analysis in n-dimensional Euclidean spaces, whose nature is of local character. Consequently, these methods lead to iterative algorithms that perform only local searches. Thus, the application of such algorithms to the calculation of global minimizers of a non-linear function, especially non-convex and multimodal, depends strongly on the location of the starting points. The Topographical Global Optimization method is a clustering algorithm, which uses an ingenious approach based on elementary concepts of graph theory, in order to generate good starting points for local search methods, from points distributed uniformly in the interior of the feasible set. The purpose of this work is two-fold. The first is a revisit to the Topographical Global Optimization method, where, for the first time, its foundations are formally described and its basic properties are mathematically proven. In this context, we propose a semi-empirical formula for computing the key parameter of this clustering algorithm, and, using a robustand efficient direction interior-point method, we extend the use of the Topographical Global Optimization method to problems with inequality constraints. The second objective is the application of this method to the phase stability analysis of mixtures, a difficult and important global optimization problem of the chemical engineering thermodynamics. Furthermore, in order to have an initial assessment of the power of this technique,first we solve 70 test problems, and then compare the performance of the method considered here with the MIDACO solver, a powerful software recently introduced in the field of global optimization.
33

Precisão de coordenadas planimétricas obtidas com receptores GNSS de pontos situados sob redes elétricas de alta tensão / Planimetric coordinate accuracy obtained with GNSS receivers located in points under high voltage electrical lines

Hillebrand, Fernando Luis 17 September 2012 (has links)
The purpose of this work was investigate and measure the possibility to exist multipath caused by the corona noise generated in high voltage electric lines recepting GNSS signals. Experiments were realized with a 69 kV tension electric line localized in Santa Maria/RS. A serie was located with eleven transversal points to the longitudinal ranging of the transmission line. In this points, the eletromagnetic field was estimated using an equipment to measure the electromagnetic field EM-8000 model. Valuations was realized about the interferences on positioning by the absolut method, using a GNSS receiver with C/A code Garmin GPS II Plus model and the positioning by the relative method with the GNSS receiver L1/L2 Topcon Hiper model. To estimate the interference in the points was necessary to obtain the geodesic coordinates of this points without multipath possibilities caused of corona noise. For this was implanted a squared topographical polygonal where the support points were located far from the transmission lines, free of the electromagnetic field influence. Calculating the variances among the coordinates was necessary transform the geodesic coordinates obtained at GNSS receivers to the Local Topographic System, to make the systems compatible, using the rotation and translation model. Calculating was possible conclude that to the raising method and the geodesic equipment used in this experiment, in a 69 kV transmission line, the found discrepancies were in the standard deviation of 17,10 mm admitted to equipment GNSS receiver L1/L2 and 15 mm to GNSS receiver C/A code, in a 95% confidence level. So it was not evidenced interferences in the electromagnetic field at GNSS signal reception. / O propósito deste trabalho foi investigar e mensurar a possibilidade de haver multicaminhamento pelo efeito corona gerado em linhas elétricas de alta tensão na recepção de sinais GNSS. Foram realizados experimentos em uma rede elétrica com tensão de 69 kV localizado no município de Santa Maria/RS. Foi implantada uma série de onze pontos transversais ao alinhamento longitudinal da linha de transmissão. Nestes pontos realizou-se uma avaliação do campo eletromagnético gerado utilizando um equipamento medidor de campo eletromagnético modelo EM- 8000. Foram realizadas avaliações da interferência no posicionamento pelo método absoluto utilizando o receptor GNSS de código C/A Garmin modelo GPS II Plus e o posicionamento pelo método relativo com o receptor GNSS portadora L1/L2 Topcon modelo Hiper. Para avaliar a interferência dos pontos foi necessário obter as coordenadas geodésicas desses pontos sem possibilidades de multicaminhamento pelo efeito corona. Para isto implantou-se uma poligonal topográfica enquadrada em que os marcos de apoio localizavam-se distantes a linha de transmissão sem a influência do campo eletromagnético. Ao realizar o cálculo das discrepâncias entre as coordenadas foi necessário realizar a transformação das coordenadas geodésicas obtidas pelos receptores GNSS para o Sistema Topográfico Local para a compatibilização dos sistemas, sendo utilizado o modelo das rotações e translações. Realizando os cálculos concluiu-se que para os métodos de levantamento e os equipamentos geodésicos utilizados neste experimento, em uma linha de transmissão de 69 kV, as discrepâncias constatadas ficaram dentro do desviospadrões de 17,10 mm admitido ao equipamento receptor GNSS portadora L1/L2 e 15 m ao receptor GNSS código C/A, a nível de confiança de 95%. Assim não se constatou interferências do campo eletromagnético na recepção dos sinais GNSS.
34

Formulação teórica dos fundamentos da otimização global topográfica com análise de desempenho e aplicações à estabilidade de fases de misturas termodinâmicas / Theoretical formulation of fundamentals of topographical global optimization method with performance analysis and applications to the phase stability of thermodynamic mixtures

Marroni de Sá Rêgo 23 February 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Métodos de otimização que utilizam condições de otimalidade de primeira e/ou segunda ordem são conhecidos por serem eficientes. Comumente, esses métodos iterativos são desenvolvidos e analisados à luz da análise matemática do espaço euclidiano n-dimensional, cuja natureza é de caráter local. Consequentemente, esses métodos levam a algoritmos iterativos que executam apenas as buscas locais. Assim, a aplicação de tais algoritmos para o cálculo de minimizadores globais de uma função não linear,especialmente não-convexas e multimodais, depende fortemente da localização dos pontos de partida. O método de Otimização Global Topográfico é um algoritmo de agrupamento, que utiliza uma abordagem baseada em conceitos elementares da teoria dos grafos, a fim de gerar bons pontos de partida para os métodos de busca local, a partir de pontos distribuídos de modo uniforme no interior da região viável. Este trabalho tem dois objetivos. O primeiro é realizar uma nova abordagem sobre método de Otimização Global Topográfica, onde, pela primeira vez, seus fundamentos são formalmente descritos e suas propriedades básicas são matematicamente comprovadas. Neste contexto, propõe-se uma fórmula semi-empírica para calcular o parâmetro chave deste algoritmo de agrupamento, e, usando um método robusto e eficiente de direções viáveis por pontos-interiores, estendemos o uso do método de Otimização Global Topográfica a problemas com restrições de desigualdade. O segundo objetivo é a aplicação deste método para a análise de estabilidade de fase em misturas termodinâmicas,o qual consiste em determinar se uma dada mistura se apresenta em uma ou mais fases. A solução deste problema de otimização global é necessária para o cálculo do equilíbrio de fases, que é um problema de grande importância em processos da engenharia, como, por exemplo, na separação por destilação, em processos de extração e simulação da recuperação terciária de petróleo, entre outros. Além disso, afim de ter uma avaliação inicial do potencial dessa técnica, primeiro vamos resolver 70 problemas testes, e então comparar o desempenho do método proposto aqui com o solver MIDACO, um poderoso software recentemente introduzido no campo da otimização global. / Optimization methods that use optimality conditions of first and/or second order are known to be efficient. Commonly, such iterative methods are developed and analyzed in the light of knowledge concerning the mathematical analysis in n-dimensional Euclidean spaces, whose nature is of local character. Consequently, these methods lead to iterative algorithms that perform only local searches. Thus, the application of such algorithms to the calculation of global minimizers of a non-linear function, especially non-convex and multimodal, depends strongly on the location of the starting points. The Topographical Global Optimization method is a clustering algorithm, which uses an ingenious approach based on elementary concepts of graph theory, in order to generate good starting points for local search methods, from points distributed uniformly in the interior of the feasible set. The purpose of this work is two-fold. The first is a revisit to the Topographical Global Optimization method, where, for the first time, its foundations are formally described and its basic properties are mathematically proven. In this context, we propose a semi-empirical formula for computing the key parameter of this clustering algorithm, and, using a robustand efficient direction interior-point method, we extend the use of the Topographical Global Optimization method to problems with inequality constraints. The second objective is the application of this method to the phase stability analysis of mixtures, a difficult and important global optimization problem of the chemical engineering thermodynamics. Furthermore, in order to have an initial assessment of the power of this technique,first we solve 70 test problems, and then compare the performance of the method considered here with the MIDACO solver, a powerful software recently introduced in the field of global optimization.
35

Shear Behaviour of Sand-geosynthetic Interfaces Based on Size And Morphology of Sand Particles and Surface Roughness of Geosynthetics

Vangla, Prashanth January 2016 (has links) (PDF)
Geosynthetics are used in conjunction with soil/particulate materials to serve various functions like reinforcement, drainage, filtration and containment. The shear behavior of soil-geosynthetic interfaces hugely depends upon on the morphological properties of particulate materials and surface characteristics of geosynthetics. However, many researchers have ignored the effects of morphology, owing to the difficulty in finding the morphological characteristics of sand particles. Few of them used visual, manual and imaged based quantifications, which are not very effective. Also, the effects of particle size and morphology are often combined and the individual effect of these parameters cannot be easily separated. In addition to this, there are very few studies which have given importance to quantitative understanding of surface features/roughness of geosynthetics and almost all of them are limited to 2D surface measurements. The objective of this thesis is to understand the interface shear mechanisms of sand-geosynthetic systems through modified large interface direct shear tests coupled with morphological characterization of sands using advanced image based and optical techniques and surface topographical analysis of geosynthetics using 3D interferometry. The individual effects of particle size and morphology on interface shear mechanism are investigated by carefully selecting the sands having specific size fractions and different morphological characteristics. A new computational method based on image analysis is proposed in this study to quantify the morphology of sands (roundness, sphericity and roughness) more accurately by writing several algorithms and implementing them in MATLAB. The roundness and sphericity of sand particles in this method are quantified as per Wadell (1932) and Krumbein and Sloss (1963) respectively and the root mean square roughness is used as a measure of surface roughness. Out of total four sands, namely coarse sand (CS), medium sand (MS), fine sand (FS) and angular coarse sand (ACS) used in this study, CS, MS and FS have similar morphology and different particle sizes, whereas CS and ACS have same size and dissimilar morphology. The effects of size and morphology of sand particles on the interface shear behavior are examined through direct shear tests on dilative and non-dilative interfaces. After examining the boundary effects on deformation patterns analyzed using shear bands in conventional, fixed box and symmetric interface direct shear tests, symmetric interface direct shear test is observed to show uniformity in stresses and deformations across the shear box and hence the same is adopted in this thesis. Test results revealed that the peak interface friction and dilation angles in case of dilative interfaces are hugely dependent upon the interlocking between the sand particles and the asperities of geosynthetic material, which in turn depend on the relative size of sand particles and asperities. Highest interface shear strength is observed when the asperity size of the geosynthetic material matches with the mean particle size of sand, which is also manifested in terms of highest shear band thickness. Direct shear tests on non-dilative interfaces (sand-smooth geomembrane) revealed that interface friction angle depends on the number of effective contacts rather than the particle size. Morphology of sands is found to have major influence on the interface shear strength among all the parameters investigated. Results from interface shear tests are examined in the light of topographical analysis of sand particles and shear induced surface changes in geomembrane. Possible shearing mechanisms at the interface and the influence of particle size, morphology and normal stress on sliding or plowing are brought out from 3D surface roughness measurements using 3D optical profilometer. The stress-shear displacement response of sand-geomembrane interfaces are correlated to the surface changes on sheared geomembranes through visual observations and roughness quantifications. Medium sand used in this study could make more number of effective contacts with deeper grooves, resulting in highest interface friction. The number of grooves are less in case of coarse sand and the depth of grooves is less in case of fine sand, resulting in lesser interface friction for these two sands compared to medium sand, supporting the results of interface shear tests.
36

Highly-Efficient Guiding of Motile Microtubules on Non-Topographical Motor Patterns

Reuther, Cordula, Mittasch, Matthäus, Naganathan, Sundar R., Grill, Stephan, Diez, Stefan 07 September 2018 (has links)
Molecular motors, highly-efficient biological nano-machines, hold the potential to be employed for a wide range of nanotechnological applications. Towards this end, kinesin, dynein or myosin motor proteins are commonly surface-immobilized within engineered environments in order to transport cargo attached to cytoskeletal filaments. Being able to flexibly control the direction of filament motion – in particular on planar, non-topographical surfaces – has, however, remained challenging. Here, we demonstrate the applicability of a UV-laser-based ablation technique to programmably generate highly-localized patterns of functional kinesin-1 motors with different shapes and sizes on PLL-g-PEG-coated polystyrene surfaces. Straight and curved motor tracks with widths of less than 500 nm could be generated in a highly-reproducible manner and proved to reliably guide gliding microtubules. Though dependent on track curvature, the characteristic travel lengths of the microtubules on the tracks significantly exceeded earlier predictions. Moreover, we experimentally verified the performance of complex kinesin-1 patterns, recently designed by evolutionary algorithms, for controlling the global directionality of microtubule motion on large-area substrates.
37

Hospodářské dvory ve středověkých Čechách a na Moravě. Sídelní kontext a ekonomický potenciál. / Farmyards in medieval Bohemia and Moravia. The context of settlement and its economic potential.

Rak, Ondřej January 2016 (has links)
1 Abstract In this work I deal with farmyards 13th-15th century, which formed an integral part of the medieval landscape. The main attention is paid to settlement-historical context and economic potential. Attention was also focused on the methods used, archaeological surveys and surface exploration. Nobility farmyards are divided into several types, according to the economic strategy and in material form. Their form depended on the owner, the monasteries were built large courtyards and nobility smaller. The main purpose of these farmyards was to provide the economic base of the nobility. There are also farmyards that served to financial income. The most common owners were a nobility and church institutions. Mostly they were situated to rural settlemet, where they were always dominant feature. Because this is not very frequent theme in Czech archeology, the aim of this work was also to summarize current knowledge. Given the breadth of the topic, I tried to include as much information, on the other hand, I had to approach selected topics in general. Work should, however, include the most important knowledge on this topic.
38

Effects of Caffeine on Topographic Quantitative EEG

Siepmann, Martin, Kirch, Wilhelm January 2002 (has links)
Despite the widespread use of caffeine as a central nervous stimulant, the central pharmacodynamic properties of the drug have not yet been conclusively evaluated in humans. The present study was undertaken to assess the acute effects of caffeine on measures of topographical quantitative electroencephalogram (EEG) in normal subjects. Ten healthy male volunteers (mean age ± SD 25 ± 4 years) received placebo and 200 mg of caffeine as powder with oral water solution (caffeine amount = 2 cups of coffee) under randomized, double-blind crossover conditions on two different occasions. Before administration and 30 min afterwards, a 17-channel quantitative EEG was recorded during relaxation with eyes open and closed (15 min each). Caffeine caused a significant reduction of total EEG power at fronto-parieto-occipital and central electrode positions of both hemispheres when the subjects kept their eyes open. Absolute power of the slow and fast alpha and slow beta activities was diminished in various regions of the brain (p < 0.05). The effect was more pronounced with the subjects keeping their eyes open than with eyes closed. It can be concluded that quantitative EEG is a sensitive method to assess the effects of psychostimulants on the human brain. Therefore, in pharmaco-EEG studies, environmental factors such as caffeine have to be excluded. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
39

The Enlightenment Travels North : The ideology and practice in parish descriptions in early modern Norrland

Persson, Johan January 2023 (has links)
This thesis is a study of factory owner Abraham Abrahamson Hülphers’s collections of parish description about the parishes in Norrland, more specifically those about Medelpad and Ångermanland. The thesis seeks to explain how Hülphers’s collections were created in practice while also presenting the descriptions content and analysing the ideology it reproduced. It does so by analysing Hülphers’s published descriptions, his travel journal and some of his correspondence. The thesis uses Mary Louise Pratts ideas about the imperial gaze as a theoretical framework to understand the work of Hülphers and the relation between the enlightened middle class and the peasantry which they described. The thesis investigates the idea of the parish descriptions understood as Hülphers travel journal reworked, arguing that Hülphers journey through Norrland was important for social reasons, rather than information gathering, and presenting the collections as new texts, not transformed versions of the journal. Furthermore the thesis discusses who helped Hülphers create the descriptions and the impact these men, from the same enlightened middle class as Hülphers himself, had on the text. The thesis also handles the economic ideology of the enlightenment as mirrored and reproduced by the descriptions. Here the focus lies on the priorities of the parishes different lines of work and the boundless optimism of enlightenment man – as nature could be conquered completely by man’s reason. Finally the thesis discusses the way Hülphers described the local culture; what he considered to be virtues and vices in the peasant population in terms of habits, language and dress, also showing the great value he considered the local dignitaries to have and discussing his disdain towards the superstitions of old as these could lead a community towards chaos.
40

Massbalansmodellering av fosfor i ett åländskt kustområde : en utredning om lokaliseringen av Lotsbroverkets utloppsledning

Eklund, Jenny January 2004 (has links)
<p>This report is commissioned by the Water and Sewage Agency in The City of Mariehamn, Åland. The basic aim is to investigate positive or negative effects of a relocation of the sewage pipe from a wastewater treatment plant, Lotsbroverket. The environmental licence of Lotsbroverket is to be revised and The Environmental Appeal Board at Åland’s Government and Administrative Board has made demands that several possible locations in an outer water area should be examined. The present location of the sewage pipe is in Svibyviken, which has been classified as an “inner water area”.</p><p>The objective of this work is to study to which extent the nutrient loading from Lotsbroverket influence the environmental conditions in Svibyviken, and to investigate the suitability of different locations of the wastewater pipe from Lotsbroverket.</p><p>The way a coastal area looks, i.e., its morphometry, determines to a large extent its ecological characteristics. The investigated coastal area was digitalized from a nautical chart. The software used for this was Roots 3.3 and the GIS-tool ArcGIS 8.3. The localization of the coastal boundaries for the entire coastal area and for investigated sub-areas was determined according to the topographical bottleneck method, i.e., the boundary lines were drawn where the exposure of the coast to the open sea is minimized.</p><p>A process-based dynamic mass-balance model for total phosphorous has been used in this study. Using this model, one can estimate and quantify the effects of different nutrient sources in coastal areas. All the fluxes of phosphorous to, from and within the defined areas were studied and ranked. Model simulations have shown how changes in any of the phosphorous fluxes influence the mean monthly concentrations of total phosphorous. The situation for total nitrogen was determined with a statistical/empirical regression model between phosphorous and nitrogen concentrations. To estimate the expected ecological effects from a change in the nutrient loading from Lotsbroverket, statistical/empirical correlations between modelled nutrient concentrations and ecological effect variables have been used. Standard effect variables for the study of eutrophication effects in coastal areas are, e.g., the chlorophyll concentration, Secchi depth and oxygen saturation in deep water. These variables have also been used in this study.</p><p>It has been shown that (1) the nutrient concentrations of the Baltic Sea controls the concentration of nutrients in the studied areas to a very large extent, (2) that the nutrient fluxes from Lotsbroverket are small compared to the nutrient fluxes from the Baltic Sea and hence also of minor importance for the nutrient state of the receiving water system, (3) that the influence of the nutrient emissions from Lotsbroverket are most noticeable in the present inner recipient, Svibyviken, and (4) that the impact logically decreases with distance between the location of the sewage pipe and boundary line to the open sea. The overall conclusion is that no major improvement of the conditions in Svibyviken can be expected by a reduction or a relocation of the nutrient emissions from Lotsbroverket.</p> / <p>Detta examensarbete är ett uppdrag av VA-verket vid Mariehamns stad, Åland, med syfte att utreda effekter av en eventuell flyttning av avloppsreningsverket Lotsbroverkets utloppsledning. Inför en revidering av Lotsbroverkets miljötillstånd har Miljöprövningsnämnden vid Ålands landskapsregering ställt villkor på att tillståndshavaren skall utreda möjligheter till att avleda det renade avloppsvattnet till ett yttre vattenområde. Utloppsledningen mynnar i dagsläget i Svibyviken, vilken har klassificerats som ett inre vattenområde.</p><p>Målsättningen med detta arbete är att belysa vilka ekologiska effekter näringsämnesutsläppet från Lotsbroverket har på primärrecipienten Svibyviken samt att undersöka några andra områdens lämplighet som mottagare av avloppsvattnet. Ett kustområdes utseende och form, det vill säga dess morfometri, avgör i stor utsträckning dess ekologiska förhållanden. För att få en god bild av det undersökta områdets morfometri digitaliserades området utifrån ett sjökort i digitaliseringsprogrammet Roots 3.3, varefter data bearbetades med GIS-verktyget ArcGIS 8.3. Avgränsning av kustområdet som helhet och av undersökta delområden gjordes enligt den topografiska flaskhalsmetoden, det vill säga så att kustens öppenhet mot utanförliggande hav eller vattenområde minimeras (Håkanson et al., 1984; Pilesjö et al., 1991).</p><p>För arbetet har en processbaserad, dynamisk massbalansmodell för totalfosfor använts. Modellen har tagits fram för att eutrofieringseffekter i kustområden skall kunna studeras (Håkanson & Karlsson, 2001). Vid användandet av modellen kan effekter av olika näringsämneskällor uppskattas och kvantifieras. Samtliga totalfosforflöden till, från och inom olika avgränsade områden har studerats och rangordnats. Modellsimuleringar har visat hur förändringar i något av fosfortillflödena inverkar på recipientens månadsmedelkoncentration av totalfosfor. Situationen för kväve har undersökts med hjälp av en statistisk/empirisk regressionsmodell mellan fosfor- och kvävehalt. För att belysa de ekologiska effekter som kan förväntas efter en förändring av Lotsbroverkets fosfor- och kväveutsläpp har statistiska/empiriska kopplingar gjorts mellan näringsämneskoncentrationer och ekologiska effektvariabler. Bra effektvariabler vid undersökning av eutrofieringseffekter är exempelvis klorofyllhalt, siktdjup samt syrgashalt i bottenvattnet. Dessa variabler har också använts i detta arbete.</p><p>Resultaten visar att (1) närsaltskoncentrationerna i de studerade områdena i hög grad styrs av den allmänna eutrofieringsnivån i Östersjön, (2) att utsläppet av näringsämnen från Lotsbroverket inte inverkar på recipientens näringsstatus i någon stor utsträckning, (3) att Lotsbroverkets påverkan är störst på nuvarande recipient, Svibyviken, (4) och att påverkan sedan successivt minskar ju längre ut mot öppna havet utloppsledningen lokaliseras. Slutsatsen av utredningen är att en reduktion av Lotsbroverkets utsläpp eller nylokalisering av utloppsledningen inte kan förväntas ge någon omfattande förbättring av tillståndet i Svibyviken.</p>

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