“Vattenfrågan har alltid varit viktig på Gotland” (Bastani et al. 2015, p. 25)  - “Water questions have always been important on Gotland”. Contrary to the common perception that water shortage does not pose a problem to northern European countries, the case on Gotland provides the example that it is a real issue. Due to several factors, the Swedish island faces severe water shortages during the summer and is in urgent need to address this in the light of an expected growing number of people coming to Gotland. Since water is a topic affecting a wide range of stakeholders, the water issue is already in the focus of attention and occasionally passionately discussed on the island. The aim of this paper was to identify with the help of qualitative research how relevant stakeholder groups perceive and address the water shortage on Gotland. The identified stakeholder groups were from the administrative/political sectors, industrial/business sectors, the research sector as well as engaged citizens. During the research it became clear that the water shortage can be characterized as a wicked problem, which in its nature is impossible to solve but only manageable due to its complexity. Yet, the majority of stakeholders did not recognize the wicked problem as such which explains the multiplicity of existent strategies for how to deal with it. The different approaches lead to outcomes that seem to only address parts of the problem but fail to manage it in its entirety. The study suggests that institutional voids, meaning a lack of clear responsibilities regarding who should manage the problem and how seem to both arise from and contribute to the complexity of the problem. As result of this research, it seems crucial to firstly gain a comprehensive understanding of the situation and then work with multi stakeholder communication and cooperation against prevailing institutional voids in order to address the water shortage effectively.

Moisture-induced damage is one the major causes of deterioration of asphalt pavements and extensive research has been conducted on this topic. Theoretical and experimental results have led the researchers to believe that moisture-induced damages are caused mainly by the generation of pore water pressure in asphalt mixtures when traffic passes over a pavement. The Moisture Induced Sensitivity Tester (MIST) has been recently developed to simulate the phenomenon of repeated pore pressure generation and deterioration in the laboratory. The objective of this study was to evaluate moisture-induced damage in typical Maine Department of Transportation (DOT) asphalt mixes, with the use of MIST, pre and post testing, and analysis of data. The MIST was used to condition Hot Mix Asphalt (HMA) samples that were compacted from eight typical Maine DOT mixes, with different types of aggregates and asphalt binder. A modified Dynamic modulus test in Indirect Tensile Mode was used for the determination of damage. A layered elastic model, along with a fatigue-cracking criterion, was utilized to assess the total impact on the pavement lives. Monte Carlo analysis was conducted to determine the distribution of number of repetitions to failure of pavements that are subjected to moisture damage. The major conclusions are that most of the mixes are likely to experience a reduction in their life due to the effect of moisture and that the Micro-Deval and the fine aggregate absorption test results can be related to such damage. A composite factor, consisting of both of these test results, is recommended for regular use by the DOT to screen mixes with high moisture damage potential.

Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2017-09-26T13:05:25Z No. of bitstreams: 1 Tiago Silva de Souza_.pdf: 989483 bytes, checksum: 54a4ff4a17ced1ad3c89fe08ea1cc911 (MD5) / Made available in DSpace on 2017-09-26T13:05:25Z (GMT). No. of bitstreams: 1 Tiago Silva de Souza_.pdf: 989483 bytes, checksum: 54a4ff4a17ced1ad3c89fe08ea1cc911 (MD5) Previous issue date: 2017-06-14 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Institutional voids are typically found in emerging economies. When governments lack in essential facilities, in order to ensure the well function of their supply chains, companies have to properly deal with this situation by themselves. An example is a situation happening in Rio Grande do Sul, Brazil, since 2013, where a sequence of investigations focused on the dairy industry. Due to a lack of regulation, milk was the target of adulterations throughout the supply chain processes of the companies. The frauds affected processes of companies from different sizes and nationalities. However, in this context, a local cooperative called Cooperativa Languiru, one of the leader dairy companies in the state, has different practices with its suppliers and was not affected by this contingency. Thus, the purpose of this research, through a case study, was to analyze the relationship between a dairy buying company and its suppliers in this environment of regulatory institutional voids. Aiming to have a wider perspective, this qualitative study explored how the lack of institutions affected the sector. As results, it was verified that political and economic interferences affect the chain as well as political lobby acts. Likewise, the lack of inspectors and infrastructure impact the well-functioning of it. Nevertheless, the close relation between the Cooperativa Languiru with its suppliers abled the company to have record results without having situations in terms of adulteration. Thus, this study proposed a research framework conceptualizing that firms must closely manage their relations with suppliers in order to deal with institutional voids.

The so-called 'cosmic web', comprising cosmic voids and galaxy clusters, has been proven to be extremely sensitive to deviations from General Relativity. This could be further investigated by future large-scale surveys, such as with the European Space Agency satellite Euclid. In this study, the parameter |fR0| from f(R) gravity is constrained by considering the Euclid survey specications to predict the observed numbers of voids and clusters in bins of redshift, mass and, only for voids, density contrast. From these values, the Fisher matrix is computed for three values of |fR0|, 10-4, 10-6 and 10-8, by assuming a flat Universe with a component that mimics the cosmological constant. The probability density functions are obtained for |fR0| and seven other parameters from the fiducial model considered (ns, h, Ωb, Ωm, σ8, w0 and wa).

A técnica de tratamento de solos com cal ou cimento vem sendo empregada com sucesso na engenharia geotécnica, melhorando as características do solo, que por ser um material complexo e muito variável nem sempre satisfaz as necessidades da obra a ser realizada. As últimas pesquisas em solos tratados com cal mostram o desenvolvimento de metodologias de dosagem baseadas em critérios racionais (como a relação água/cimento para o concreto), onde a relação volume de vazios/volume de cal desempenha papel fundamental na obtenção da resistência desejada. O volume de vazios (ou a porosidade) é um fator importante nestas metodologias de dosagem, e ainda não existem técnicas que quantifiquem este fator (como o ensaio de porosimetria por injeção de mercúrio para o concreto) e também modelos que permitam o entendimento do comportamento da porosidade dessas misturas o longo do tempo de cura (como o modelo de Powers para o concreto). Assim, esta pesquisa tem como objetivo verificar a influência da quantidade de cal (Ca), da porosidade (h), do teor de umidade (w) e do tempo de cura (t), sobre a resistência à compressão simples (qu), sobre a resistência à tração (qt) e sobre a rigidez inicial (Go) de um solo siltoso estabilizado com cal (misturas caulim-cal), verificando a adequação do uso da relação vazios/cal na estimativa de qu, qt e Go. Além disso, esta pesquisa busca quantificar a porosidade dessas misturas solo-cal e também desenvolver um modelo, que permita o entendimento do comportamento da sua porosidade ao longo do tempo de cura. Para atingir os objetivos da pesquisa foram realizados ensaios de resistência à compressão simples, ensaios de resistência à tração por compressão diametral, ensaios para a medida de Go, ensaios de sucção matricial e ensaios de porosimetria por injeção de mercúrio. Os resultados dos ensaios de resistência à compressão simples, de resistência à tração e de rigidez inicial demonstram que o aumento da quantidade de Ca, a diminuição da h e o aumento do t provoca o aumento de qu, qt e Go. Sendo que, qu, qt e Go crescem linearmente com o aumento da quantidade de cal e exponencialmente com a redução da sua porosidade. Assim, verifica-se que, a relação vazios/cal (h/Cav), definida pela razão entre a porosidade da mistura compactada e o teor volumétrico de cal, demonstra ser um parâmetro adequado na estimativa de qu, qt e Go. A partir desses mesmos resultados, observase que a w também desempenha um papel fundamental na previsão de qu, qt e Go. Além disso, a partir dos ensaios de resistência à compressão simples, resistência à tração e rigidez inicial, observa-se que a existência de relações únicas e distintas no controle de qu, qt e Go em função da h, do Cav e da w mostrou-se muito eficiente para relações de dosagem. Relações entre qu, qt, Go e h/Cav também, foram muito satisfatórias. Além disso, foram realizadas análises estatísticas dos dados obtidos neste experimento, e os resultados demonstram, a partir da análise da variância, que todos os fatores controláveis escolhidos no experimento são significativos. Os resultados dos ensaios de porosímetro por intrusão de mercúrio demonstram que a porosidade diminui com o tempo de cura. Porém, o modelo de Powers não se adaptou perfeitamente na previsão da variação da porosidade das misturas caulim-cal estudadas. / The technique of treating soil with lime or cement has been used successfully in geotechnical engineering, improving the characteristics of the soil, which is a highly variable and complex material, and does not always meet the needs of the earthwork to be performed. The last researches in soils treated with lime are in the development of dosage methodologies based on rational criteria (such as water/cement ratio for concrete), where the voids/lime ratio plays a fundamental role in the assesstment of the target strength. The void volume (or porosity) is an important factor in these dosage methodologies, and there are not techniques that quantify this factor (as the test porosimetry with intrusion of mercury, for concrete) and also models that allow understanding the behavior of porosity for these mixtures in long curing times (such as the Powers’s model for concrete). Thus, this research aims to determine the influence of the amount of lime (Ca), porosity (h), moisture content (w) and curing time period (t) on the unconfined compression strength (qu), tensile strength (qt) and initial stiffness (Go) of a silty soil stabilized with lime (kaolin-lime mixtures), checking the suitability of the use of voids/lime ratio in estimating qu, qt and Go. Besides, this research aims to quantify the porosity of these soil-lime mixtures and also adjusting a model that allows understanding the behavior of their porosity during the curing time. For that, a number of unconfined compression tests, splitting tensile tests, the measurement of Go, measurement of matric suction and porosimetry with intrusion of mercury tests were carried out in present work. The results of unconfined compression strength, tensile strength and initial stiffness show that increasing the amount of Ca, decreasing of h and increasing of t, causes increased of qu, qt and Go. Further, qu, qt and Go grow linearly with the increased amount of lime and exponentially with reducing its porosity. The voids/lime ratio, defined as the ratio of the compacted mixture porosity and the lime volumetric content, adjusted by an exponent, proves to be an appropriate parameter to estimate the qu, qt and Go. From these results, it is observed that the w also plays a fundamental parameter in predicting the qu, qt and Go. Moreover, it is noted that the existence of distinct and unique relationships in the control of qu, qt and Go according to h, Cav and w proved to be very efficient for dosage relationships. Relations between qu, qt, Go and h/Cav were very satisfactory too. Furthermore, statistical analyzes were performed of the results obtained in this experiment, and results demonstrate, through analysis of variance, that all controllable factors chosen in the experiment are significant. The results of test porosimetry with intrusion of mercury show that the porosity decreases with increasing curing time. However, the Powers’s model has not adapted perfectly to predict the variation of the porosity of kaolin-lime mixtures studied.

The purpose of this research is to empirically investigate flow front void formation rates and post-formation bubble mobility behavior for composites produced via resin transfer molding (RTM).For this study, in situ observation of bubble formation and migration was accomplished by photographing resin flow progression during infusion tests of carbon reinforcements. An analysis strategy for use in batch processing sequential image sets is presented. The use of MATLAB to process and analyze binary images of infusions for void content has garnered satisfactory results and has shown that analysis of progressive image sequences can greatly enrich the volume of in situ measurements for a given study without compromising the data quality.Semi-automated MATLAB software analysis employed the representative image area (RIA) method to evaluate v0. It was found that the shorter the RIA length, and the more it follows the true flow front shape, the more representative the measured v0 was of the void formation at the flow front.Experimental evidence of in situ bubble formation and mobility behavior is presented. Stitch architecture of NCF reinforcements is shown to influence bubble formation at the flow front. Bubble mobility mechanisms (such as escape and entrapment) are related to stitch orientation relative to the fluid flow direction. Different stitching orientations exhibited different effects on post-formation mobility.Void formation is presented as a function of flow front velocity. Despite differences in preform configurations (stitch orientation with respect to flow) and injection flowrates, bubbles seem to form in a similar fashion for the 3 infusions of carbon fiber NCF reinforcement analyzed in this study. It is observed that bubbles form at stitch lines, regardless of stitch orientation.Bubble migration is documented for infusion of NCF reinforcement with stitching at different orientations. Qualitative observations of bubble migration during infusions of a dense preform of STW, plain weave fabric are discussed. Recommendations are given for future studies involving image-based analysis of in situ bubble formation and migration.

Cette thèse de cosmologie est consacrée à l'étude de l'empreinte de l'énergie noire sur la formation des structures de l'Univers. Je défini et introduit les régions cosmiques compensées comme l'environnement à grande échelle autour des extrema locaux dans le champ de densité. Dans le cas d'un minimum central, cette région peut être identifiée aux vides cosmiques usuels. A l'aide de simulations numériques, je montre que ces régions présentent des propriétés de formes particulières et qu'elles dépendent de la cosmologie. Je montre que la forme moyenne de ces profils de densité ainsi que leur propriétés statistiques peuvent être calculée analytiquement dans l'Univers primordial. En utilisant une dynamique appropriée, je montre qu'il est possible de suivre précisément l'évolution non linéaire de ces structures. Il devient alors possible de reconstruire les profils de matières observés aujourd'hui à partir les profils théoriques primordiaux évolués selon une dynamique appropriée. J’exhibe une propriété fondamentale de ces régions qui maintient constant une taille particulière, le rayon de compensation. Autour de ce point, l'évolution non linéaire du champ de matière peut être suivie analytiquement. En étudiant l'effondrement gravitationnel dans des théories étendues de gravité, je montre qu'il est possible de contraindre efficacement la nature de la gravité et de la cosmologie à partir de l'étude de certaines propriétés spécifiques à ces régions. Ce travail permet à la fois de donner une origine aux profils de matière sur les très grandes échelles cosmiques mais aussi de définir de nouvelles sondes cosmologiques pour tester la nature de notre Univers. / This thesis is devoted to the study of the imprints of dark energy on the formation of the large scale structures in the Universe. I define the spherically compensated cosmic regions as the large-scale environment around local extrema in the density field. For central minimum, this region can be identified with standard cosmic voids. Using numerical simulations, I show that these regions, once properly identified, can be used efficiently to distinguish competitive cosmological models. I show that the average shape of these density profiles and their statistical properties can be analytically computed in the primordial Universe. Using an appropriate dynamical formalism, I show that it is possible to follow the nonlinear evolution of these structures until today. This allows to reconstruct the shape of such large scale regions from first principles. I exhibit a fundamental property of these regions which maintains constant a particular size : the compensation radius. Around this radius, the nonlinear evolution of the matter field can be analytically derived. By studying the gravitational collapse in gravity models beyond General Relativity, I show that it is possible to constrain efficiently both cosmology and the nature of gravity. Beside giving a physically motivated model for both shape and statistical properties of such large scale matter profile, this work also define new cosmological probes that could be used to test the nature of our Universe.

Earthen dams and levees create high gradients and increased hydraulic pressures in the underlying soil, which can lead to erosion and other challenges. Karst formations and other defects such as cracks in the foundation and/or abutments can lead to failure mechanisms such as internal erosion. Generally these voids or cracks are filled with soil, but due to the increased pressures and gradients that dams and levees create, the original soil is pushed out, thus creating a void that acts as a conduit for more soil to follow. Different soils will erode at different rates and some even create a natural filter, preventing further erosion from occurring, but due to these increased gradients and the cyclic changes that can occur throughout the seasons these filters can be broken down, allowing for erosion to continue and potentially lead to complete failure of the structure unless certain reparatory measures are taken. In the lab we have simulated different conditions that exist in the field and the results of testing a variety of soils can be found in this paper.

The PhD thesis evaluates the mechanical properties and damage tolerance of aerospace carbon/epoxy laminates containing long, narrow interlaminar galleries. The term 'galleries' refers to thin and long holes in a laminate used for the installation of small measuring devices, such as structural health monitoring (SHM) sensors. The galleries considered in this study are similar to those used in a novel SHM system known as 'Comparative Vacuum Monitoring (CVM)'. CVM was developed by the Australian company - Structural Monitoring Systems (SMS) - for damage detection in aircraft structures. CVM is a SHM system that utilises pressure differentials between a parallel series of galleries at atmospheric or low pressure to detect damage initiation and propagation. Thus far, CVM has been used for the monitoring of surface cracks in metallic structures using surface mounted sensors. Recent research has also demonstrated that it may be possible to monitor damage along the bond- line of both metallic and composite joints using CVM. The ability of CVM sensors to detect delamination damage inside composite structures is less well understood. It is envisaged that CVM can be used for the through-life health monitoring of composite aircraft structures prone to delamination damage. However, a major concern with applying CVM to composite laminates is the open-hole design of the galleries that may initiate damage growth under external loading. Material property data, structural tests, and models for predicting the properties of laminates containing galleries is needed before CVM technology can be certified for use in aircraft composite structures. The primary objectives of this PhD thesis are the development of an optimum process method for introducing multiple interlaminar CVM galleries in composite laminates; the development of a validated model for calculating changes to the mechanical properties of laminates containing CVM galleries; and the determination of optimum CVM gallery shape, size and orientation combinations for minimising the effect of the galleries on the mechanical properties of laminates. The effects of the shape, size and orientation of CVM galleries on the mechanical properties of carbon/epoxy laminates are evaluated by an extensive experimental research program, and the results are presented in the thesis. The properties investigated include the in-plane tensile and compressive properties, tensile and compressive fatigue life, through-thickness tensile strength, interlaminar shear strength, mode I and mode II interlaminar fracture toughness, and impact damage resistance. The results from tensile tests on lap-joints and T-joints containing CVM galleries are also presented.

<p>The directive of the European parliament and of the council on the Restriction of the use of certain Hazardous Substances (RoHS) in Electrical and Electronic Equipment (EEE) took effect in the European Union on July 1, 2006. Japan, California, China and Korea are all closed markets for exporters of components containing lead from July 1, 2007. Taiwan and Australia are working with similar directives. The RoHS directive is the reason why this thesis about the implementation of lead-free soldering in highly reliable applications is necessary.</p><p>The European Lead Free soldering NETwork (ELFNET) status survey from 2005 shows that the majority of the companies are well informed, but 20% are still not active in lead-free soldering. The Swedish industry is for the most part prepared and 95% of the components are lead-free. The transition to lead-free soldering will have a major affect on logistics and administration, because the RoHS directive is 90% about administration and logistics problems. Only 10% is technical problems.</p><p>The higher melting point in lead-free soldering affects every stage of the lead-free manufacturing, from assembly to testing and repair.</p><p>The major concern for highly reliable applications are that there are not enough data to understand to what grade lead-free solders will perform differently from lead based solders. Five different types of reliability testing were studied in this thesis; vibration, mechanical shock, thermal shock, thermal cycling and combined environments. Whiskers, voids, brittle fractures and mixed assembly problems were also studied. Individual tests alone should not be used to make definite decisions on lead-free soldering reliability. The lower reliability for lead-free solders in some tests does not necessarily mean that lead-free solders not can be used in highly reliable applications like defence electronics.</p><p>The most important conclusions from this thesis are:</p><p>• Update or change the logistic system and mark/label according to available standards.</p><p>• Secure a good board layout.</p><p>• Secure a good process control.</p><p>• Alternative surface board should be used. Tin-silver-copper (SAC) is the most reliable solder and Electroless Nickel/Immersion Gold (ENIG) is the most reliable surface finish.</p><p>• Remember that the higher temperature affects every stage of the manufacturing.</p><p>• No increased problems with whiskers or risk of high voiding levels.</p><p>• Mixed assembly is a risk. Compatibility and contamination risks must be taken seriously.</p><p>• Which environment will the applications be in? If it is not a highly vibrating and thermal cycling environment, lead-free soldering should be safe to use.</p> / <p>Europaparlamentets och rådets direktiv om begränsning av användningen av vissa farliga ämnen i elektriska och elektroniska produkter började gälla i Europeiska unionen 1 juli, 2006. Japan, Kalifornien, Kina och Korea är alla stängda marknader för exportörer av komponenter som innehåller bly från och med 1 juli, 2007. Taiwan och Australien arbetar med liknande direktiv. RoHS-direktivet är anledningen till varför detta examensarbete om implementeringen av blyfri lödning i högtillförlitliga applikationer är nödvändigt.</p><p>En undersökning från 2005 av ELFNET visar att majoriteten av företagen är väl informerade, men 20% är fortfarande i aktiva med blyfri lödning. Den svenska industrin är till största delen väl förberedd och 95% av komponenterna är blyfria. Övergången till blyfri lödning kommer att ha stor effekt på logistik och administration, därför att 90% är administrations- och logistikproblem i RoHS-direktivet. Bara 10% är tekniska problem.</p><p>Den högre smälttemperaturen i blyfri lödning påverkar varje steg av den blyfria tillverkningen, från montering till testning och reparation.</p><p>Den stora oron för högtillförlitliga applikationer är att det inte finns tillräckligt med data för att förstå i vilken grad som blyfria lod kommer att bete sig annorlunda jämfört med blybaserade lod. Fem olika typer av tillförlitlighetstester har undersökts i detta examensarbete; vibration, mekanisk chock, termisk chock, termisk cykling och kombinerade tester. Whiskers, voids, sprödbrott och blandad montering studerades också. Individuella tester ska inte användas för att ta några definitiva beslut om blyfri lödnings tillförlitlighet. Den lägre tillförlitligheten för blyfria lod i en del tester behöver nödvändigtvis inte betyda att blyfria lod inte kan användas i högtillförlitliga applikationer som försvarselektronik.</p><p>De viktigaste slutsatserna från detta examensarbete är:</p><p>• Uppdatera eller byt logistiskt system och märk enligt tillgängliga standarder.</p><p>• Säkerställ en bra kretskortsdesign.</p><p>• Säkerställ en bra processkontroll.</p><p>• Alternativa mönsterkort bör användas. SAC är det tillförlitligaste lodet och ENIG är den tillförlitligaste ytbehandlingen.</p><p>• Kom ihåg att den ökade temperaturen påverkar varje steg i tillverkningen.</p><p>• Inga ökade problem med whiskers eller stort antal voids.</p><p>• Blandmontage är riskfyllt. Kompatibilitet och risker med kontaminering måste tas på allvar.</p><p>• Vilken miljö kommer applikationen att befinna sig i? Är det inte en starkt vibrerande eller temperaturcyklisk miljö bör blyfri lödning vara säkert att använda.</p>