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Os defeitos superficiais são os maiores problemas de qualidade em barras laminadas a quente, representando inúmeros transtornos durante o processo produtivo, pois dependendo de suas características geram elevada rejeição durante o processo de inspeção. Elevada rejeição significa retrabalho e possível sucateamento. Dentre as diversas causas para a ocorrência de defeitos superficiais, estão os defeitos nos tarugos, a temperatura de laminação, conseqüência da temperatura de reaquecimento e ritmo de laminação e a remoção de carepa após o reaquecimento. Definiu-se o aço SAE 1043 para o desenvolvimento deste trabalho devido aos níveis de rejeição superficial e elevados volumes de produção, o que gera grande impacto na produção das linhas de inspeção. Os resultados obtidos a partir dos testes realizados demonstram que a temperatura de laminação até determinado limite não tem influência na rejeição superficial, mas que abaixo deste gera elevado índice de rejeição. O uso do descarepador tem grande influencia nos níveis de defeitos superficiais, e o controle de seus parâmetros principais é fundamental. O condicionamento superficial dos tarugos é o parâmetro que mais apresentou influência positiva sobre a rejeição superficial, demonstrando que defeitos pré-existentes na matéria-prima têm grande impacto no produto final da laminação. / Surface defects are major quality problems in hot rolled bars, representing numerous disturbances during the production process, as depending on their characteristics generate high rejection during the inspection process. High rejection means rework and scrap. Among the various causes for the occurrence of surface defects are defects in the billets, rolling temperature, a consequence of the reheating temperature and rate of roll and removal of scale after reheating. The steel SAE 1043 used in this work was selected due to its level of surface defects and high production volumes, which generates large impact on production inspection process. The results show that the rolling temperature of up to a certain limit does not influence the surface defects, but below this generates a high rate of rejection. The use of descaling has a large influence on the levels of surface defects, and control of its main parameters is essential. The surface conditioning of billets is the parameter that showed a positive influence on the reduction of surface defects, demonstrating that pre-existing defects in materials has large impact on the final rolled product.

Flood risk management is increasingly seeking to involve local stakeholders in decision-making, both to harness and benefit from their tacit knowledge and to devolve responsibility for delivering local-scale, individual and community responses. Current techniques used in flood risk management centre on a techno-scientific approach, which is well-suited to appraising and modelling hazard, but often inaccessible to those without specialist, technical expertise. This leads to participation that is often limited to infrequent consultation periods, keeping local stakeholders at the periphery of the decision-making process. Their absence from the more technical elements of the process can leave local stakeholders struggling to understand how different options have been identified, appraised and/or prioritised. This can in turn lead to dissatisfaction with process outcomes, lack of support for selected options, and foster distrust in expert practitioners. This thesis explores how participatory modelling techniques could complement current approaches, facilitating the co-production of models with local stakeholders that explore social constructions of risk, and the vulnerability of different receptors. It identifies the qualities that are sought from participation, including the need to remain highly accessible, yet sufficiently robust to capture the complexities encountered when working at the interface of social and physical systems. Reporting on two UK case studies, it exemplifies the benefits that two popular techniques, Bayesian networks and system dynamics, can deliver at different stages in the flood risk decision-making process. In each case, the effectiveness of the participatory approach is assessed using an evaluative framework that advances current approaches by including an early assessment of context, as well as a detailed exploration of substantive (user-defined goals), and social change outcomes. The holistic nature of the evaluation framework, and its population with practical criteria bespoke to flood risk management, enhance its transferability between different contexts. The thesis finds that participatory modelling techniques support the collating of diffuse tacit knowledge, building of consensus, strengthening of social networks, and the empowerment of local citizens to become volunteer risk managers; provided that process managers are willing to simplify the techniques to maintain accessibility, and be open to different metrics of success.

Scientific studies have suggested an increase in the frequency and intensity of flooding. The research presented herein is focused on a small watershed, which has experienced intense flooding of a downstream, urbanized area. For emergency response and preparedness, it is pertinent to have the ability to predict intensity and peak flows of a flood. The Town of Dyer, Indiana has been severely impacted by flooding in the last twenty years. A 37.6 square mile watershed begins in a rural section of Illinois with tributaries draining into Plum Creek. The creek crosses into Indiana and becomes Hart Ditch, a straight, narrow, deep channel through the urbanized Town of Dyer. A HEC-HMS hydrologic model was used and calibrated based on USGS gage data. Storm events ranging from short, high intensity to long, intermittent precipitation provided a vast representation of possible scenarios within the watershed. The hydrologic model was paired with an unsteady HEC-RAS hydraulic model to allow for different lateral inflows to the creek providing variations of flow. A comparison between upstream and downstream stream gage readings was utilized to create a working model that predicts downstream water surface elevations for previous real-time storm and hypothetical storms. These conditions were analyzed by two stream gages and a correlation between the two gages was developed. This correlation was used to predict downstream water surface elevations. The correlation was also used to determine the time to crest based on readings at the upstream gage for many different storm events. The ability to know downstream water surface elevations for real-time storm events allows a window of time to implement emergency response in areas where flooding is imminent. The downstream area of concern has known flood elevations that represent various damage levels.

This dissertation examines the interactions between social movement organizations and a variety of state and municipal targets of movement activity during the construction of the Illinois Hydraulic Fracturing Regulatory Act (HFRA). Hydraulic fracturing is a controversial method of oil and gas extraction which created an unusual amount of public interest and participation in policy construction. This dissertation provides an overview of the political environment in Illinois during the legislative negotiations for the HFRA, outlining the playing field of political negotiations, and the relative positioning of social movement actors competing for influence in that field. Additionally, I examine the causes and consequences of conflict between coalition partners opposed to fracking, focusing on the impact of differential resources, expertise, and institutional legitimacy. Using data from interviews with organization leaders from industry and environmental coalitions, key informants from government bureaus, and participant observation at public meetings, my research contributes to the political process literature by elaborating the heterogeneity of the state’s interests in political challenges and revealing cleavages within social movement coalitions.

The Saline Valley Conservancy District (SVCD) formed in 1980 to provide groundwater to communities in Saline and Gallatin, Counties, Illinois. Sulfate contamination from a nearby coal mine threatens the SVCD’s current well field. Three of the wells are reaching the end of their service and have elevated levels of sulfate. This study investigated multiple well configurations on three different parcels of land to find possible new well locations that do not recharge water directly from the mine site over a 50-year period. A steady-state finite difference groundwater flow model was created using Graphic Groundwater GIS (Krienert and Esling, 2016), a pre and post-processor for MODFLOW (Harbaugh, 2005) and MODPATH (Pollock, 2012). The calibration and sensitivity analysis followed methods from Esling et al. (2008). Hydraulic heads were calibrated to the land surface and a systematic sensitivity analysis varied recharge, hydraulic conductivity, and drain and river conductance to produce composite capture zones. Well locations must also meet SVCD requirements that would minimize distance from current water lines and consider properties they already owned. New wells also needed to be located in areas where the aquifer exceeds 25 m thick and be separated by 305 meters to minimize drawdown. This study also considered the effects of irrigation on the aquifer. Varying recharge, hydraulic conductivity and conductance within reasonable ranges created six capture zones for the proposed wells, each with different geometries. The capture zones were superimposed onto a map to make a composite capture zone which should contain the actual capture zone for the wells. Varying conductance caused subtle changes in capture zone geometry. Low values of conductance caused particle tracks to elongate. Irrigation wells and some proposed well locations caused substantial dewatering in one area of the aquifer. The study discovered several well configurations on each of the parcels that do not source water from the mine site over 50 years.

The redevelopment of existing riverine barriers with modern hydropower turbines is becoming increasingly prevalent on main stem rivers with valuable stocks of migratory salmonids. This is a concern because these fish rely on longitudinal connectivity to complete their lifecycles, and modifications for hydropower could jeopardize that connectivity by obstructing or injuring migrating fish. In order to exploit very low head hydropower potential, novel turbine types are emerging. The Archimedean screw hydropower turbine is one such technology which is becoming increasingly popular for low-head applications. However the impact of these turbines on fish movements remains largely untested. This thesis aims to provide much needed evidence on the effects that these turbines and schemes may have on migrating salmonids. Fixed radio and passive integrated transponder receivers were used to track the downstream movements of wild migrating juvenile salmonids through a low-head Archimedean screw hydropower scheme. Atlantic salmon smolts were found to pass through the alternative routes of the turbine and main river channel in proportion to flow through these channels. Passage times were generally fast through both routes (median = 17.6, range = 5.1-905.6 minutes over the 350m scheme extent, for radio tagged fish), and longer passage times were associated with daytime presence in both routes. The majority of PIT tagged Atlantic salmon and sea trout smolts that passed through the 100 m long turbine channel, did so in under 27 minutes (median = 6.8 minutes), whilst a few fish had much longer passage times, associated with daytime presence. There were no differences in onward survival (measured as distance survived downstream) between turbine passed and non-turbine passed migrants. Atlantic salmon smolts were passed through an Archimedean screw turbine to test for harmful effects from the turbine, with comparison to equivalently handled non-turbine passed smolts. There was no evidence of visible damage aside from low to moderate scale loss, which was not significantly associated with turbine passage. Blood chemistry parameters were used to test for subtle turbine-induced damage. This novel application of these techniques did not yield conclusive results, but serves as a useful precedent for future studies. Radio and PIT telemetry equipment were used to investigate the movements of upstream migrating adult salmonids at three separate low-head hydropower schemes which may act as obstacles to migration. These schemes each had distinct configurations and flow management regimes. Movements within, and progression beyond these schemes varied substantially between sites, and in some cases were related to flow management parameters. Whilst not conclusive, the results suggest that scheme configuration and the management of flows influence the time that fish spend at such schemes, and the proportion of fish that ascend beyond them. With the global shift towards renewable energy generation, the exploitation of running water for hydropower is likely to become increasingly pervasive. The results of these studies provide valuable information for the informed and ecologically sustainable development of low-head hydropower schemes.

Ballast water has been identified as a major vector for the translocation of Non- Indigenous Invasive Species (NIS) and pathogens across zoogeographical regions and subsequent discharged into recipient port states/regions. This is bound to increase given factors like the globalization of trade and the economy of scale of the ship size. Established NIS has posed significant threat to the human health, economy, finances and marine bio-diversity of recipient regions and port states. The risks associated with the discharged NIS are uncertain and difficult to assess due to the stochastic nature of species assemblages and dispersal mechanism. The safest control measure advocated by the IMO is the conduct of ballast water exchange at sea while appropriate and effective proto-type treatment technologies are being developed and approved for future application. This study has been conducted while recognizing the inability of probabilistic approaches applied in ballast water risk management to addressing uncertainty and inadequacy of data. A qualitative approach using powerful multi-criteria decision making techniques and the safety principles of the Formal Safety Assessment framework have been utilized in this research to develop three generic models for ballast water hazard estimation, risk evaluation and decision-making analysis respectively. The models are capable of being modified and utilized in the industry to address the problems of uncertainty and inadequacy of data in ballast water management. This is particularly useful as an interim measure for port states in developing economies (with insufficient data and technology) to developed robust ballast water management plans. While recognising the huge impact of ballast water pollution in recipient regions this study recommends that ballast water management programmes be given due recognition as an important element of sustainable development programmes at national and international levels. The non-availability of a benchmark based on previous research on which to fully validate the research outcome was identified as a major limitation of this research study. The models developed will therefore be subject to modifications as new data become available.

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