Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2006. / Includes bibliographical references (leaves 168-173). Also available in electronic version.

The objective of this Thesis is to develop a methodological framework to guide the decision maker in selecting a decommissioning method for offshore wind farms which is supported by the majority of relevant stakeholders. Initially, a literature review has been conducted to find out which methods are available to decommission an off-shore wind farm and which criteria can influence the outcome.Two methods have been found in literature, namely partial and total removal of the foundation. Furthermore, twenty one (21) criteria have been found which could influence the results. These criteria can be divided in four categories which are economical, environmental, social and technical.Subsequently, a methodological framework was developed that included four steps. First, the possible decommissioning methods should be identified. Following on that, information should be collected and stakeholders should be selected. Subsequently, criteria should be selected and as last a multi criteria decision aid method should be used. It is expected that this procedure would lead to a decommissioning method which is supported by most of the stakeholders.To validate the methodological framework, a case study in the Netherlands has been selected. For this case study, four (4) stakeholders were identified and eleven (11) criteria were assessed. The outranking multi-criteria decision aid method PROMETHEE II was selected and results were obtained. Analyzing the results, it was possible to conclude that only one stakeholder preferred the total removal method while the other three stakeholders preferred the partial removal method.

Thesis (M.S.) in Geological Sciences--University of Maine, 2001. / Includes vita. Includes bibliographical references (leaves 106-114).

Thesis (M. S.)--Universidad Autónoma de Baja California, 1998. / Includes bibliographical references (leaves 108-112).

xi, 91 leaves : ill. Typescript Thesis (M.S.)--University of Oregon Includes vita and abstract Bibliography: leaves 87-91 Another copy on microfilm is located in Archives University of Oregon theses, Dept. of Biology, M.S., 1982

The early marine period for juvenile salmon is a critical life history stage for growth and survival. The health of near-shore ecosystems where juvenile salmon spend their early marine life, and the capacity of these habitats to provide prey are thus important for overall salmon returns. While near-shore habitat is generally accepted as being of critical importance, few studies have examined how juvenile salmon use this habitat during their early marine life. Understanding the trophic dynamics in these ecosystems and the characteristics of these habitats that are important for food provision will help us gauge the value of near-shore areas to the early marine phase of juvenile salmon. The importance of this avenue of research is underscored by declined rates of early marine survival of salmon, and suggestions that the rapid development of the shoreline is contributing to this decreased survival. My project investigates the role that near-shore habitat plays in promoting growth and survival of juvenile salmon by evaluating eelgrass as foraging grounds for juvenile salmon in the Comox Estuary, British Columbia. In 2015, we compared juvenile Chum salmon diets to prey availability in zooplankton tows and in epifaunal and infaunal eelgrass samples across a gradient of eelgrass shoot density. We complemented diet analysis with the use of stable isotope ratios of carbon (δ13C) and nitrogen (δ13N) to examine the relative contribution of zooplankton, eelgrass, and terrestrial invertebrates to juvenile Chum salmon diet. In 2016, we collected additional eelgrass samples to cover a wider range of eelgrass density, and compared juvenile Chinook salmon diets to prey availability in eelgrass. Prey invertebrates, such as polychaete worms, harpacticoid copepods, and amphipods, increased with eelgrass shoot density. Juvenile Chum salmon and juvenile Chinook salmon assessed in this study fed primarily on benthic species, specifically on harpacticoid copepods, which were only abundant in epifaunal eelgrass samples. The abundance of prey invertebrates in eelgrass beds and the benthic diet of juvenile salmon in the Comox Estuary leads us to conclude that the presence of eelgrass is an important habitat feature for juvenile salmon. / Graduate

Ice plays an important role in hydraulic processes of rivers in cold regions such as Canada. The formation, progression, recession and breakup of river ice cover known as river ice processes affect river hydraulics, sediment transport characteristics as well as river morphology. Ice jamming and break up are responsible of winter flash floods, river bed modification and bank scour. River ice cover monitoring using terrestrial images from cameras installed on the shores can help monitor and understand river ice processes. In this study, the benefits of terrestrial monitoring of river ice using a camera installed on the shore are evaluated. A time-lapse camera system was installed during three consecutive winters at two locations on the shores of the Lower Nelson River, in Northern Manitoba and programmed to take an image of the river ice cover approximatively every hour. An image analysis algorithm was then developed to automatically extract quantitative characteristics of the river ice cover from the captured images. The developed algorithm consists of four main steps: preprocessing, image registration, georectification and river ice detection. The contributions of this thesis include the development of a novel approach for performing georectification while accounting for a fluctuating water surface elevation, and the use of categorization approach and a locally adaptive image thresholding technique for target detection. The developed algorithm was able to detect and quantify important river ice cover characteristics such as the area covered by ice, border ice progression and ablation rate, and river ice break up processes with an acceptable accuracy.

Combined simulation and optimization models, which are helpful for long-term groundwater planning of complex nonlinear aquifer systems, are developed using alternative modelling approaches. The models incorporate a representation of steady-state, quasi-three-dimensional head response to pumping within an optimization . An embedding model which describes exactly the nonlinear flow of an unconfined aquifer is presented. In contrast with the embedding models presented in the Utah State University Ground Water Model, it directly achieves the optimal solution without a "cycling." To address the nonlinearity of the flow system, response matrix models couple superposition with the cycling procedure. Their linear influence coefficients are generated using a modified McDonald and Harbaugh model. First, these models are tested for a hypothetical, 625 cell, nonlinear aquifer system and compared in terms of computational accuracy and efficiency. All of the models achieve the same optimal solution. The fully nonlinear embedding model attains the same optimal solution regardless of how far the initial guess is from that solution. Thus, global optimality is probably obtained. A predictive program for comparing a priori the embedding and response matrix models in terms of computational size is also developed. This computes the required memory for running each model, an important factor in computational efficiency. It is based on the number of nonzero elements in the matrix of the optimization scheme. The model most appropriate for a given aquifer and desired management scenarios is dependent upon required simulation accuracy, flow conditions (steady or unsteady) , spatial scale, model computational resources requirement, and the computational capacity of available hardware and software. The linear embedding model coupled with a cycling procedure, as incorporated within a modified version of the USUGWM, is most appropriate for the subject reconnaissance level study of the East Shore Area. Here, the demand for sufficient water of adequate quality is increasing. The underlying aquifer is three-layered, unconfined/confined and is discretized into 4,880 finite-difference cells. To overcome the difficulties of solving many nonsmooth functions describing evapotranspiration, discharge from flowing wells, and drain discharge, a former cycling procedure is improved by optimizing the purely linearized models repeatedly. Using the modified version of the USUGWM, optimal sustained-yield pumping strategies are computed for alternative future scenarios in the East Shore Area.

The purpose of this work is to generate a shore profile algorithm to be used in estuaries dominated by fine sediments. Numerical models are continually evolving to enhance the overall accuracy of results. However, the typical shore profile is defined as a vertical wall. This work defines the shore as a nonlinear profile which will provide more realistic models. A variety of shore profile equations were examined and tested against a field site, Weeks Bay, Alabama. The most applicable, an equation by S. C. Lee, was modified in order to calculate the entire shore profile length. The distance from the land-water interface to the depth at which sedimentation is negligible can now be modeled with a single equation. Recommendations for the practical aspect of implementation into a numerical model are also considered.

The south Brevard coast of Florida is a major nesting ground for the Atlantic loggerhead turtle (Caretta caretta). A beach restoration project was completed in the winter of 1980-81 at Indialantic and Melbourne Beach. A study was conducted to investigate the effects of beach restoration on marine turtle nesting during the summer months of 1981 and 1982. A 3.1 km restored beach study area and two control beach study areas, each 3.1 km in length and consisting of natural beach sands, were established. The entire study area (9.3 km) was monitored for nesting and non-nesting emergences (false crawls) and a tagging program was established. The objectives of the study were to determine the effects of the restoration project on the nesting behavior of adult female turtles, and to develop an understanding of the effects of restored beach sands on the survival of marine turtle eggs and hatchlings. During the 1981 nesting season 2,766 marine turtle emergences were recorded. The nesting success rates (nesting emergences/total emergences x 100) for 1981 on the north control beach and the south control beach were 54% and 51% respectively, whereas the restored beach had a statistically significant lower nesting success of 28%. This reduction of nesting success was attributed to a compact substrate that was markedly less friable than the sands of the control beaches. In 1981, the turtles emerging to nest in the restored area often displayed aberrant digging behavior when they encountered the compact sand. By the following summer of 1982, it was evident that the restored beach substrate was less compact. The nesting success for 1982 in the restored beach (46%) rose to a level equal to that of the control beaches (48% and 46%). A total of 3,144 marine turtle emergences were recorded in the 1982 nesting season. To study the effects of beach restoration on the eggs and hatchlings, nests were marked, left to incubate on the beach, and later excavated to determine hatch success. Hatch data and hatchling emergence data were collected on 30 clutches in each of the three beach sections for both the 1981 and 1982 seasons. No significant difference was found between the hatch percentage for the restored beach and the hatch percentages for the control beaches in either study year. The hatchling emergence data, which would indicate the hatchlings' ability to emerge from the sand, indicate no significant difference between the restored beach and control beaches for 1981 and 1982.