In this thesis, I explore the flow dynamics associated with ice shelves confined within channels and the buttressing they provide to grounded ice. Ice shelves are the floating extensions of ice sheets and act as the interface between the ice sheet and the ocean. They form when ice flows out from the interior of the ice sheet towards the coast and begins to float as the ice thins. Ice shelves are often found within a channel or pinned in place by stationary bedrock outcrops. The interest in their dynamics is motivated by the buttressing effect they provide to the grounded ice, which strongly controls the rate of ice discharge and thereby the contribution to sea-level rise. I use a combination of mathematical modeling, fluid-mechanical laboratory experiments and geophysical data analysis to develop an improved understanding of ice-shelf flow dynamics. Initially, geophysical data in the form of Antarctic ice-surface velocity data is analysed, producing maps of strain rate, shear rate and strain orientation for Antarctic ice shelves. This allows the geophysical setting and flow processes to be explored, particularly by identifying areas where resistance to ice flow is generated and regions of the shelf that make no contribution to buttressing. Using the geophysical data, I find good agreement between a theoretical scaling relationship for ice flow at the ice-shelf calving front and data from Antarctic ice shelves. I proceed to develop an idealized mathematical model of an ice shelf confined to flow in a channel. By assuming shear-dominated dynamics within the shelf, analytical solutions are obtained for steady-state ice-shelf thickness profiles in parallel and diverging channels. This model is developed further to include both shear and extensional stresses, from which numerical solutions for steady-state shelves are calculated. The results from these two models are then compared. It is found that shear stresses dominate the dynamics throughout the majority of the shelf, with adjustment regions at the upstream and downstream boundaries where extensional dynamics become important. Output from these models is also compared with geophysical data and it is observed that there is good agreement between several features of the thickness profiles and velocity fields. In addition to the geophysical data, comparisons are made with fluid-mechanical laboratory experiments designed to simulate the flow of an ice shelf in a channel. The advantage of performing experiments of this kind is that parameters such as the fluid rheology can be varied, allowing for direct comparison with a range of parameters in the mathematical models. From these experiments, surface velocity fields and thickness profiles are collected, which are used to make comparisons with the models. Clear differences are observed in the velocity and strain-rate fields produced using fluids with different rheologies, for which there is qualitative agreement with the output from the mathematical models.

Submitted by Marcelo Sant'Anna (marcelos@fgvmail.br) on 2010-07-20T19:55:28Z No. of bitstreams: 1 dissertVF.pdf: 409746 bytes, checksum: ca7db8bc8077f795d693bed9b119adac (MD5) / Approved for entry into archive by Andrea Virginio Machado(andrea.machado@fgv.br) on 2010-07-22T12:27:19Z (GMT) No. of bitstreams: 1 dissertVF.pdf: 409746 bytes, checksum: ca7db8bc8077f795d693bed9b119adac (MD5) / Made available in DSpace on 2010-07-23T19:33:54Z (GMT). No. of bitstreams: 1 dissertVF.pdf: 409746 bytes, checksum: ca7db8bc8077f795d693bed9b119adac (MD5) Previous issue date: 2010-07-07 / We develop a model to study shelf space allocation in retail. Retailers compete for consumers not only choosing prices but also by the space allocated to each product on shelves. Our approach depart from the existing literature on shelf allocation, as we model the problem of price setting and shelf allocation in an oligopolistic retail market. We present a simple model of retail competition in which prices are dispersed in the crosssection of stores but shelf allocation is not.

Submitted by Caroline Falcao (caroline.rfalcao@ufpe.br) on 2017-05-25T17:17:49Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação Amanda Yumi Otsuka.pdf: 1257140 bytes, checksum: 4ae2b3d501e90eaac61afd7db72c977e (MD5) / Made available in DSpace on 2017-05-25T17:17:49Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação Amanda Yumi Otsuka.pdf: 1257140 bytes, checksum: 4ae2b3d501e90eaac61afd7db72c977e (MD5) Previous issue date: 2014-02-11 / A plataforma continental de Pernambuco caracteriza-se por possuir um declive suave, ser estreita, rasa, com águas relativamente quentes, elevada salinidade e por apresentar- se quase inteiramente coberta por sedimentos carbonáticos biogênicos. Esse ambiente é afetado pelo aporte continental, atuando como um receptor final de água, materiais e substâncias, que são transportados pelas descargas dos rios. Desta forma, as regiões costeiras são as mais afetadas pela ação antrópica. O presente trabalho apresentou como objetivo analisar a dinâmica da clorofila-a e parâmetros hidrológicos na plataforma continental de Pernambuco adjacente aos rios Jaboatão e Capibaribe. Foram realizadas coletas bimestrais, abrangendo período chuvoso e de estiagem, em um ponto situado na zona estuarina e quatro outros pontos distribuídos na plataforma. Foram analisados vários parâmetros ambientais como clorofila a, profundidade, salinidade, temperatura, oxigênio dissolvido, taxa de saturação do oxigênio, pH, nutrientes inorgânicos (N- amoniacal, nitrito, nitrato, fosfato e silicato), material particulado em suspensão. A pluviosidade foi a forçante física que mais influenciou na maioria dos parâmetros. No rio Jaboatão, a clorofila-a no estuário variou de 2,89 à 34,71 mg.m-3 e na plataforma de 0,21 à 9,67 mg.m-3 . De acordo com a ACP, a clorofila a esteve diretamente relacionada temperatura, taxa de saturação do oxigênio e inversamente com o pH, transparência da água e salinidade. No porto do Recife, a clorofila a variou entre 13,48 à 145,09 mg.m-3 no estuário e na plataforma a de 0,24 à 19,29 mg.m-3 . A ACP mostrou uma relação direta da clorofila-a com o N-amoniacal, fosfato, transparência e inversa com nitrato e material particulado em suspensão. Nas duas áreas estudadas, houve um aumento da biomassa no período de estiagem. Os pontos da plataforma que mais sofreram influência do deságue foram os mais centrais (P3 e P4), devido ao predomínio dos ventos alísios de sudeste. Após análise das duas áreas, observou-se que os estuários encontram-se poluídos e que no porto do Recife a carga de matéria orgânica é bem mais elevada do que o Jaboatão, provocando maior efeito na plataforma adjacente. Em termo de dispersão de pluma dos rios, no porto do Recife a presença do dique de proteção provoca uma certa perturbação no sentido da corrente, limitando esta pluma, para a parte mais costeira, o que não foi observado na área do Jaboatão. / The continental shelf of Pernambuco is characterized by a gentle slope, it is narrow, shallow, almost entirely covered by biogenic carbonate sediments; the water in the area is warm and has a high salinity. This environment is affected by continental input, and acts as a final receptor of water, materials and other substances that are transported by river discharge. Thus, the coastal regions are the most affected by human action. This study aims to analyze the dynamics of chlorophyll-a and hydrological parameters on the inner shelf of Pernambuco adjacent to the Jaboatão and Capibaribe rivers. The samplings were performed bimonthly at one research site on the estuarine zone and four additional sites distributed on the platform, covering the dry and rainy seasons. Various environmental parameters such as chlorophyll-a, depth, salinity, temperature, dissolved oxygen, oxygen saturation rate, pH, inorganic nutrients (ammonia, nitrite, nitrate, phosphate and silicate), and suspended particulate matter were analyzed. Rainfall was the most influent physical forcing to most parameters. In the Jaboatão River, chlorophyll-a ranged from 2.89 to 34.71 mg.m–3 in the estuary; and from 0.21 to 9,67 mg.m-3 at the platform. According to the PCA , the chlorophyll-a was directly related to temperature, oxygen saturation rate and inversely with the pH, water transparency and salinity. In the Port of Recife, chlorophyll-a ranged from 13.48 to 145.09 mg.m-3 in the estuary and from 0.24 to 19.29 mg.m-3 in the inner shelf. The PCA showed a direct relationship of chlorophyll-a with ammonia, phosphate and water transparency an inverse relationship with nitrate and suspended particulate matter. In both studied areas, there was an increase in biomass in the dry season. In the inner platform , The most central sites (P3 and P4) were the most influenced by river discharge, due to the dominance of trade winds from the southeast. After analysis of the two areas, it was observed that the estuaries are polluted and that, in the Port of Recife, the load organic matter is much higher than in Jaboatão causing greater effect on the adjacent platform. In regarding the river’s plume dispersion in the Port of Recife, the presence of the dike causes some disturbance in the direction of the current. The plume is then limited to the most coastal area. This fact was not observed in the Jaboatão area.

Orientador: Valdemiro Carlos Sgarbieri / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-05T21:56:49Z (GMT). No. of bitstreams: 1 Ziegler_FabianeLaFlor_M.pdf: 1806557 bytes, checksum: c7746abef0196b047e712da90766b294 (MD5) Previous issue date: 2006 / Resumo: O principal objetivo da presente pesquisa foi desenvolver um produto dietético funcional para idosos desnutridos. Para tal, realizou-se inicialmente a caracterização físico-química e nutricional das fontes protéicas: isolado protéico do soro de leite bovino (WPI) e hidrolisado de colágeno bovino (HCB), buscando-se adequar a proporção entre elas, bem como, avaliar algumas de suas propriedades físicas, composição, perfil de aminoácidos e propriedade nutricional. Posteriormente foi realizado o desenvolvimento do produto através de testes preliminares, caracterização físico-química, testes sensoriais e de vida de prateleira. Na 1ª etapa do trabalho observou-se que o componente de maior concentração foi a proteína para as duas amostras (~ 92%). A solubilidade foi elevada tanto do WPI como do HCB o que refletiu, conseqüentemente, na solubilidade da mistura dessas proteínas. O perfil de aminoácidos essenciais (EAE) do WPI atende às recomendações da Food and Agriculture Organization (FAO)/World Health Organization (WHO), no entanto o HCB apresenta deficiência em vários aminoácidos essenciais, particularmente em triptofano e aminoácidos sulfurados. Do ponto de vista nutritivo, os índices quociente de eficiência protéica (PER), utilização líquida da proteína (NPU), valor biológico aparente (VBa) e balanço de nitrogênio (BN), as misturas WPI:HCB (60:40 e 80:20) não diferiram estatisticamente entre si e do WPI (p > 0,05), sendo inferior (p < 0,05) à caseína comercial (CC) usada como referência. Em função dos resultados obtidos, optouse pela mistura 60% WPI: 40% HCB como componente protéico na formulação do produto dietético funcional, por razões econômicas. Nos testes preliminares avaliaram-se diferentes combinações e proporções entre os ingredientes para a obtenção da melhor formulação, principalmente em relação à solubilidade e ao aspecto sensorial. A escolha destes ingredientes, bem como a quantidade usada foi baseada em pesquisas na literatura a respeito do perfil nutricional de idosos e suas principais deficiências. Através da análise sensorial (testes de aceitação, ideal de doçura e intenção de compra) com idosos foram escolhidas as formulações sabor chocolate e sem adição de sabor dentre seis opções, as quais receberam médias de aceitação de 6,87 e 6,60, respectivamente, numa escala de nove pontos. Essas formulações apresentaram em torno de 12% de proteína e 80% de carboidratos com adição de inulina, frutooligossacarídeos (FOS), cálcio, zinco, magnésio, selênio e as vitaminas B1, B6, ácido fólico, B12, A, C e E. Com as formulações foi realizado estudo da vida útil do produto durante 30 dias de estocagem em temperatura ambiente e a 35 °C usando-se filme de polipropileno como material de embalagem. Realizaram-se análises de umidade, atividade de água (aw), isoterma de adsorção, taxa de permeabilidade ao vapor de água (TPVA), cor, avaliação sensorial e perda de vitaminas. O produto apresentou aw inicial abaixo de 0,3, valor característico de alimentos desidratados. As isotermas de adsorção foram utilizadas para determinação dos valores de aw crítica (0,5), umidade crítica (5,1%) e umidade inicial (~2,0%), os quais foram usados nos cálculos da estimativa da vida útil do produto. Observou-se pequena variação na cor (_E* = 0,4 para formulação sem saborizante e 0,6 para a formulação chocolate) durante os 30 dias de estocagem. A qualidade sensorial manteve-se satisfatória nas três avaliações (tempo zero, 15 e 30 dias), obtendo-se médias de aceitação acima de 5 para os todos atributos. Mais de 65% dos provadores tiveram intenção de compra entre ¿certamente compraria¿ e ¿tenho dúvidas se compraria¿. Através desses resultados, constatouse uma maior preferência pela formulação chocolate. Verificou-se uma diminuição apreciável no teor das vitaminas B1, C, A e E ao final da estocagem. Através do ganho de peso das formulações estimou-se a vida de prateleira do produto, a qual foi de aproximadamente 4 meses. Dessa forma, recomenda-se o uso de embalagens com maior proteção, no caso de uma possível comercialização ou administração a idosos, evitando-se a degradação dos nutrientes mais sensíveis e conseqüente diminuição do valor nutricional do produto / Abstract: The main objective of the present investigation was the development of a functional dietetic product for undernourished elderly. First step was the chemical, physical and nutritional characterization of protein component, a mixture of whey protein isolate (WPI) and a bovine collagen hydrolysate (HCB) both materials containing around 92% protein and showing high solubility in water. The essential amino acid profile (EAE) of the WPI reaches all the requirements of the FAO/WHO reference standard, however the HCB is deficient in all essential amino acids, particularly in cysteine and tryptophan which is totally absent in collagen. The nutritional indices PER, NPU, VBa and nitrogen balance (NB) of the two mixtures WPI:HCB (60:40 and 80:20) respectively, did not show statistical difference (p > 0.05) among themselves and with the WPI. Nevertheless they were inferior (p < 0.05) to a commercial casein (CC) used as reference. The choice was for the mixture WPI:HCB (60:40) for economical reasons. The choice of ingredients, composition and concentrations in the formulation was based mainly in three criteria, i.e., solubility, sensorial aspects and nutritional deficiencies of elderly population, based on literature surveys. In sensorial tests (acceptance, ideal sweetness and buying attitude) conducted with an elderly group for six different formulations, the choice was for the formula dissolved in milk with chocolate flavor and the other with no flavouring added. The acceptance scoring was 6.87 and 6.60 respectively, for the two formulations using a 9 ¿ point scale. The two formulations contained around 12% protein and 80% carbohydrate in addition to inuline, frutooligosaccharides (FOS), calcium, zinc, magnesium, selenium and the vitamins B1, B6, folic acid, B12, vitamin A, C and E. A shelf life study was conducted with the two formulations during 30 days under the laboratory environmental conditions and at 35 °C. Humidity, water activity (aw), adsorption isotherm, water vapor permeability rate (WVPR), color, sensorial evaluation, mineral and vitamin analysis were performed. Water activity at time zero (T0) was below 0.3, characteristic of dehydrated powder. The adsorption isotherms were used for determination of the critical aw (0.5), critical moisture content of 5.1% and initial moisture of about 2.0%, which were used for the estimation of the product shelf life. A small color variation was observed (_E* 0.4 for the formulation without flavouring and 0.6 for the chocolate formula), during the 30 days of storage. Sensorial qualities were satisfactory for all three storage time (T0, T15 and T30), with an average acceptance score above 5. More than 65% of the panel demonstrated buying intention between ¿certainty of buying¿ and ¿doubt of buying¿. Higher preference was for the chocolate formula. Appreciable losses of the vitamins B1, C, A and E were detected during storage in both samples, independently of the storage condition. The shelf life estimated was of approximately 4 months for both formulations. It is recommended that a packaging material with more barrier to water vapor, light and oxygen must be used for product to minimize losses of the more unstable vitamins / Mestrado / Nutrição Experimental e Aplicada à Tecnologia de Alimentos / Mestre em Alimentos e Nutrição

A lichia é uma fruta exótica de origem chinesa que cada vez mais tem ganhado espaço no mercado interno brasileiro, contudo problemas de pós-colheita existentes prejudicam a comercialização e a exportação de forma significativa. Diversos métodos são utilizados na tentativa de controlar estes problemas, um destes sendo a irradiação ionizante. Desta forma este trabalho tem como objetivo avaliar os efeitos de diferentes doses de radiação e de diferentes temperaturas nas características físico-químicas de frutos de lichia. Os frutos foram obtidos com produtores da região de Piracicaba e irradiados no Centro de Energia Nuclear na Agricultura em uma fonte de 60Co em um irradiador GammaCell 220 nas doses de 0 (testemunha), 0,5kGy, 1,0kGy e 2,0kGy com uma taxa de 0,259 kGy/h. Foram realizadas análises de pH, de cor da casca e da polpa, de teor aparente de sólidos solúveis, de acidez total e de teor de ácido ascórbico. Os resultados obtidos foram submetidos à análise de variância através de teste F a 95% de confiança e posteriormente a teste de Tukey a 5% de significância. As doses de irradiação apresentaram resultados variados dependendo da característica analisada, porém a dose de 1,0kGy apresentou os resultados mais favoráveis no geral. A redução da temperatura causou alterações desejáveis nos parâmetros estudados. Concluiu-se que os frutos de lichia armazenados a 8°C e irradiados a 1,0 kGy apresentaram melhoria significativa. / The lychee is a Chinese exotic fruit that has increasingly gained ground in the Brazilian domestic market, however existing post-harvest problems hinder the marketing and export significantly. Various methods are used in attempts to control these problems, one of these being ionizing irradiation. Thus this work aims to evaluate the effects of different radiation doses and different temperature on the physicochemical characteristics of litchi fruit. The fruits were obtained with producers of Piracicaba region and irradiated in the Center for Nuclear Energy in Agriculture into a source of 60Co in Gammacell 220 radiator at doses of 0 (control), 0.5kGy, 1.0kGy and 2.0kGy at a rate of 0,259kGy / hr. Were performed pH analyzes, color ratings, apparent soluble solids content measurement, total acidity and ascorbic acid content measurement. The obtained results were submitted to variance analysis by F test at 95% confidence and later to Tukey test at 5% significance. The irradiation doses showed varied results depending on the characteristic analyzed, but the dose of 1.0kGy presented the most favorable results in general. The temperature reduction caused desirable changes in the studied parameters. It was concluded that fruits stored at 8°C and irradiated at 1.0 KGy exhibited significant improvement in the physicochemical characteristics of the litchi fruits

Orientador: Roberto Herminio Moretti / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-04T07:20:31Z (GMT). No. of bitstreams: 1 Camargo_GiseleAnne_D.pdf: 2325645 bytes, checksum: fa7c229e01b708eab93a1f58ce091081 (MD5) Previous issue date: 2005 / Resumo: A concentração osmótica e outros pré-tratamentos visam melhorar a qualidade do produto e otimizar o processo de secagem. Dentre estes tratamentos pode-se citar o uso de antioxidantes para evitar o escurecimento excessivo e manter as características nutricionais. A incorporação de concentrado de tomate com 18 a 36 oBrix, não é um método utilizado na fabricação de tomates secos, e foi um procedimento utilizado com o objetivo de melhorar a qualidade e aumentar o rendimento do processo de secagem. E ainda a utilização de ácidos fracos em soluções utilizadas em desidratação ou concentração osmótica representa uma alternativa de processamento brando. Os objetivos gerais desta pesquisa foram: avaliar e selecionar novas tecnologias e pré-tratamentos, visando melhorar a qualidade do produto final e também aumentar o rendimento e eficiência do processo de secagem de tomate para conserva; e definir e caracterizar a vida de prateleira do produto selecionado. Esta pesquisa definiu procedimentos que permitiram aumentar a eficiência e qualidade de um novo produto: tomates secos, embalados a vácuo com umidade intermediária e com segurança ao consumidor. Foi observado que a utilização de açúcares invertidos permitem maior perda de água e entrada de sólidos no tomate. O ácido ascórbico mostrou perda nos primeiros 30 minutos de pré-tratamento osmótico. O conteúdo de licopeno aumentou a disponibilidade nos primeiros 10 minutos com posterior decréscimo gradual. Os consumidores determinaram que o sabor é o fator mais importante na aceitação do produto e desaprovaram a aplicação de concentrado triplo de tomate como pré-tratamento à secagem. A aplicação de antioxidante (metabissulfito de sódio e ácido isoascórbico) anterior à secagem com ar forçado proporcionou maiores teores de ácido ascórbico e licopeno no produto final. A relação ¿Sólidos Solúveis/Acidez Total¿ escolhida pelo paladar dos consumidores foi de 23,8 a 26,65. A melhor eficiência do pré-tratamento osmótico (solução mista de sacarose e açúcares invertidos) foi obtida quando adicionado sal entre os valores de 5,05 a 7,45% e ácido cítrico entre os limites de 6,62 -7,25%. A preferência sensorial do consumidor foi para os produtos obtidos a partir de concentração osmótica em solução com 65º Brix, com a adição de 5,85% de NaCl e 6,00% de ácido cítrico. A qualidade microbiológica do tomate seco embalado a vácuo foi mantida durante o período avaliado de 180 dias para refrigerado e 90 dias em temperatura ambiente. A construção de isotermas permitiu observar que o armazenamento em umidade relativa superior a 50% proporciona a adsorção de água ao produto, alterando as características originais do tomate seco. Os tomates desidratados osmoticamente com açúcares invertidos, sal é ácido cítrico proporcionaram atividades de água entre 0,76 a 0,86. A reconstituição e reutilização do xarope foi um procedimento eficiente no processo produtivo / Abstract: Osmotic concentration and other pre-treatments aim to improve product quality and optimise the drying process. Amongst these treatments one can mention the use of antioxidants to avoid excessive browning and maintain the nutritional characteristics. The incorporation of tomato concentrate at 18 to 36°Brix is not a method currently used in the manufacture of dried tomatoes, but could be a suitable method for quality improvement as well as increasing the yield on drying, considering that it would add up to six times the amount of soluble solids naturally present in the tomato. And the use of weak acids in the solutions used for osmotic drying or concentration represents a mild processing alternative, resulting in a product with appropriate sensory characteristics for immediate consumption. The use of a combination of additives together with various types of sugar (sucrose, fructose and glucose), especially acidifiers, in addition to their antioxidant action, help to increase the rate of osmosis. The general objectives of this research were: to evaluate and select new technology and pre-treatments aiming at improving final product quality and process yield and efficiency in the drying of tomato, and also to define and characterise the shelf life of the selected product. This research defined procedures, which allowed for an increase in efficiency and quality of a new product: vacuum-packed dried tomato with intermediate moisture content, safe for consumption. The use of invert sugar was shown to increase the efficiency of the osmotic dehydration of tomatoes, and temperatures above 45°C failed to provide the desired quality. Ascorbic acid showed losses during the first 30 minutes of pre-treatment, and the lycopene showed an increase in availability during the first 10 minutes, followed by a gradual decrease. The consumers determined that flavour was the most important factor for product approval and disapproved the application of triple concentrated tomato paste. The application of antioxidant (sodium metabisulphite and isoascorbic acid) allowed for greater retention of the lycopene and ascorbic acid. The consumers preferred products with the ¿soluble solids/total acidity ratio¿ between 23.8 and 26.65. The salt concentration in the mixed syrup of sucrose and invert sugar was shown to be more efficient in the osmotic dehydration process between the values of 5.05 and 7.45%, with a citric acid concentration between 6.62 and 7.25%. The consumers chosen (sensory analysis) products obtained from pre-treatment: osmotic dehydration in 65°Brix syrups with the addition of 5.85% NaCl and 6.00% citric acid. The microbiological quality of the product, vacuum-packed dried tomato, was maintained during the periods evaluated of 180 days under refrigeration and 90 days at room temperature. The consumers considered values for the color parameter ¿L¿ above 38.37 as unacceptable, indicating this value as an instrumental colour limit (luminosity). The dried tomato adsorbed water in Relative Humidity to up 50%. The dried tomatoes osmotically dehydrated with invert sugar, salt and citric acid, provided values for water activity the 0.76 to 0.86. The syrup could be reused efficiently / Doutorado / Tecnologia de Alimentos / Doutor em Tecnologia de Alimentos

Changes in sediment morphology on the West Florida Shelf is investigated over a 14-year time period using multibeam bathymetry and backscatter in water depths between 10 m and 20 m, off the coast of Indian Rocks Beach, Pinellas County, Florida. Bathymetric surveys collected in 2002 (Kongsberg EM 3000 at 300 kHz) and 2016 (Reson 7125 at 400 kHz) were processed using CARIS Hips and Sips to create bathymetric maps and backscatter images. These data were then interpreted and compared in order to test hypotheses and answer questions related to sediment migration and sediment volume change. The following questions prompted this study: A. How mobile is the sediment on the limestone? B. What sedimentary changes occurred following the 2002 and 2003 deployments of mines for an Office of Naval Research project? C. How much sediment was removed during dredging and how closely does it compare to the Army Corps of Engineers’ reported estimate during the beach renourishment of Sand Key in 2012? In order to answer these questions, hypotheses were proposed: Hypothesis A: The sediment ridges in the study site have not migrated significantly over the limestone hard bottom during the 14-year time period (Hafen, 2001; Edwards et al. 2003). Hypothesis B: There is no change in sediment volume where the mine-like object were placed and removed after the ONR mine burial experiment (Wolfson 2005 Wolfson et al. 2007). Hypothesis C: Changes in sediment volume between 2002 and 2016 will match the amount estimated by the Army Core of Engineers who dredged the area. Results show that the sediment ridges in the study area had some migration over the limestone hard bottom during the 14-year time period. The results also found that there was a sediment volume change where mine-like objects were placed and removed during the Office of Naval Research mine burial experiment because of a dredging operation in 2012 that dredged sediment from the experimental area. Specific areas investigated that surround the dredging area showed significant loss of sediment, with the change in hydrodynamics from dredging influencing this sediment loss. The volume of sediment removed from the aforementioned dredging cut was found to be within 16% of that estimated in the Army Corps of Engineers report prior to the dredging. Geologic interpretations of the backscatter images interpreted strong backscatter returns as limestone, mid strength returns as coarse shell hash and weak returns as fine to medium-grained sediments. The weak returns were found primarily on the sediment ridges. The dredging cut showed stronger returns than the surrounding ridge, indicating that underlying coarse sediments were most likely compacted and composed of shell hash. Using satellite remote sensing as a way to gather continual repeat coverage at high resolution (2 m) data to determine absolute depth in these water depths is investigated and preliminary results suggest that processed 250 m pixel MERIS data will give a similar depth range as multibeam bathymetry. The higher-resolution 0.5 m pixel raw WorldView 2 data shows NW-SE trending structure, suggesting the seafloor morphology will be more visible.

Master of Science / Department of Electrical & Computer Engineering / John Devore / Instead of designing new proprietary hardware to replace aging, obsolete systems, the defense industry is looking towards Components Off The Shelf (COTS). COTS are attractive for a number of reasons. First, by using COTS, nonrecurring design costs are divided among all costumers. Second, because COTS suppliers have an economy of scale, the suppliers are able to reduce the cost of components, making systems more affordable than low-volume, proprietary solutions. Third, using COTS accelerates the time to market by reducing the time required for design and making extensive design verification unnecessary. Fourth, COTS hardware produces a scalable solution, as one COTS systems could easily be replaced with a different COTS system that would more readily meet the customer's unique demands. This thesis attempts to explain the implementation of a COTS-based flight computer. The PCI Mezzanine Card (PMC) standard has been selected because it is both rugged and widely accepted by industry. The PMC is a common standard with a variety of COTS parts, making it easily exchangeable. While the COTS solution reduces design overhead, it does not eliminate the need for design altogether. Although the contractor would no longer be required to design the features provided by the COTS, they would be required to design the overall system and the integration of the COTS. This thesis documents the design of a system that takes two PMC cards – the COTS – and integrates those cards together and interfaces them with the flight systems. The interfacing of COTS components is also extended to provide a high-speed serial link in order to connect two PMC carrier boards for a total of four COTS PMCs. Further, the testability of the final system is explored to provide an end product that is verifiably sufficient.

Please read the abstract in the 00front part of this document / Dissertation (MSc (Food Science))--University of Pretoria, 2007. / Food Science / unrestricted

In the Arctic Ocean, almost 50% of the seafloor is underlain by continental shelf. However, the geology of the pre-rift continental crust that makes up the basement of the shelf is poorly constrained because it is overlain by thick Cenozoic sedimentary cover. This study explores the available data and methods for mapping the continental bedrock geology beneath the sediments. In a GIS framework, extrapolation of geological map units to the shelf edge was guided by onshore structure and offshore bathymetry. The compilation involved identification of data sources, development of a common legend for pre-rift basement geology, building attributes tables for analysis, and extrapolating geological contacts. As a first-order assessment of mineral resource potential of the continental shelf, permissive tracts for certain mineral deposit types were also identified. The analysis includes a case study of permissive geology for magmatic Ni-Cu deposits in the Taimyr Peninsula in northern Russia.