京都大学 / 新制・課程博士 / 博士(農学) / 甲第25347号 / 農博第2613号 / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 野口 良造, 教授 飯田 訓久, 教授 近藤 直 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

This study focuses on the facies changes from the lower slope to toe-of-slope to basin floor over a 10 km outcrop belt, in down-dip and oblique-strike directions to the basin margin. The Jurassic Los Molles Formation in Neuquen Basin, Argentina represents the slope and basin floor of basin margin clinoforms, coeval with the shallow water and fluvial deposits named Las Lajas and Challaco formations respectively. The shallow and deep water deposits are diachronously linked in an Early-Mid Jurassic source-to-sink system developed in a back-arc basin during the incipient development of the Andes Mountains. Satellite images, high resolution panorama pictures and measured sections were used to correlate and interpret the spatial variability and overall geometry of the base of slope to basin floor units. The observations of this study refine the model for the channel-to-lobe transition zone with increase recognition and quantification of facies and architecture variability. The Los Molles basin margin was coarse grained and was ideal to observe changes in the geometry and depositional facies of channel-to-lobe deposits from updip to downdip continuous over an 8 km outcrop belt. The described channel-to-lobe transition zone clearly shows a downdip change in bed boundaries from dominantly erosive to non-erosional (bypass) to depositional and with a range of distinct facies changes. In the transition zone the sand to shale ratio is high (N:G: 65-70 %), with gutter casts and deep scours, with a high degree of amalgamation, gravel lags, mud rip-up clasts and laterally migrating beds. Within the same depositional unit (deep water lobe), at the base of the slope, the dominant sandstone beds change from amalgamated structureless and normal graded sandstone beds in the channelized lobe axis to parallel laminated and normally graded in the channelized lobe off-axis areas. Similar facies changes have been observed along proximal to distal direction. The lateral change of the dominant structures in the beds indicates changes in the flow regime and depositional style. / text

Populations that utilize deep water running (DWR) are described in Chapter I. A review of the literature concerning maximal and submaximal responses during DWR, shallow water running and swimming is presented in Chapter II. The protocols to elicit maximal responses during DWR and treadmill running (TMR), subject characteristics, and statistical methods employed are described in Chapter III. The results, presented in Chapter IV, indicate that the DWR protocol is a reliable test for eliciting peak oxygen consumption and heart rate. Furthermore, the metabolic responses during DWR are lower than TMR. Chapter V discusses factors which might limit maximal responses during DWR. Chapter VI contains suggestions for further research. Raw data are presented in Appendix A.

Entre os produtos confeccionados com polímeros reforçados com fibras, as hastes pultrudadas têm sido utilizadas em um número crescente de aplicações devido a características como baixa massa, elevada resistência mecânica, baixo custo de manutenção e alta resistência à corrosão, em particular quando comparadas com hastes confeccionadas em materiais convencionais equivalentes. Porém, os mecanismos de envelhecimento e de degradação dos compósitos poliméricos reforçados com fibras precisam ser mais bem compreendidos, particularmente os mecanismos de dano em condições de serviço, em aplicações de engenharia civil ou em águas profundas. Neste trabalho, foi avaliada a exposição de hastes pultrudadas produzidas a partir de fibras de carbono e vidro e resinas epóxi e éster-vinílica após 3000 horas em diferentes ambientes, como exposição à radiação UV, exposição à água do mar e exposição à água a 60 °C. Os principais aspectos microestruturais, físicos, térmicos, químicos, mecânicos e de vida útil das hastes foram avaliados antes e após as exposições. As hastes com fibras de carbono apresentaram maior resistência residual de forma geral quando comparadas às hastes de fibra de vidro, as quais perderam mais de 50% da sua resistência original após exposições de curta duração (744 h). Quando expostas à radiação UV, as hastes com fibras de carbono apresentaram maior resistência residual à tração, assim como quando submetidas a esforços combinados nos ensaios de SBS. O ambiente mais agressivo entre os estudados definitivamente foi a imersão em água destilada. Os resultados dos ensaios de short-beam apresentaram melhor relação com os efeitos de degradação do que os ensaios de resistência à tração. Através das análises microestruturais (MO e MEV) foi possível identificar alguns tipos de mecanismos de degradação atuantes em cada condição de envelhecimento acelerado. Após analisar uma combinação de fatores envolvidos, a resina epóxi, dentre as resinas estudas, foi a que apresentou melhores propriedades de interface quando utilizada com fibras de carbono. / Among products made with fiber-reinforced polymers, pultruded rods have been used in an increasing number of applications, due to such features as low weight, high strength, low maintenance costs, and high corrosion resistance, particularly when compared with rods manufactured with equivalent conventional materials. However, the ageing and degradation mechanisms of these polymer composite materials still need to be better understood, particularly the damage mechanisms under various service conditions, such as civil engineering or in deep water applications. This thesis presents an experimental study that evaluates the ageing of pultruded rods produced from reinforced carbon and glass fibers and epoxy and vinyl ester resin matrices when exposed to UV radiation, seawater and distilled water at 60 °C for 3000 hours. The degradation assessment in the different environments was made by analyzing and comparing the microstructural, physical, chemical, thermal and mechanical aspects and the lifespan of the pultruded composite rods before and after accelerated ageing. The carbon fiber rods presented a higher residual resistance considering all the aforementioned aspects when compared to the glass fibers rods, which lost more than 50% of their original resistance after short exposure (744 h) to weathering. When exposed to UV radiation, the carbon fiber rods showed higher residual resistance as compared with other types of degrading conditions. Distilled water was undoubtedly the most aggressive ageing factor in respect to all the evaluated properties and characteristics of the tested rods. The short-beam test results showed higher correlation with the degradation effects than the results of the tensile test. By means of microstructural analysis (SEM and OM), it was possible to identify some types of degradation mechanisms for each kind of applied accelerated ageing. After analyzing a combination of factors involved, it was possible to reach the conclusion that the epoxy resin incorporated with carbon fibers displayed the best overall performance among all possible resin/fiber couples

This paper examines the regional longshore sediment transport pattern of the seaward coast of the United States and Gulf of Mexico from northern Maine to Tampa Bay, Florida. From previous studies it is known that along the coast there are variations in direction of sediment transport known as nodal zones as well as variations in sediment transport rate. Wave Information Study (WIS) hindcast data for the interval 1976 through 1995 (United States Army Corps of Engineers, 2003) provide a spatially continuous model of the regional longshore current directions in the study area. In chapter one, all available published field studies of longshore current direction and sediment transport directions and rates are compiled to create a description of the direction and, whenever possible, magnitude of longshore transport. A detailed compilation of regional and local published studies are provided in tables. An interpretation of sediment transport rates and directions is provided in eight regional maps of the study area. In chapter two the results of the literature compilations are compared with gross and net potential sediment transport directions and rates modeled using WIS hindcast data. The WIS deep-water wave characteristics are used to predict the directions and rate of longshore sediment transport at local outer coast positions using the method of Ashton et al. (2003a). The WIS-derived transport directions, including nodal zones, generally agree with the published field studies, although there are a few local inconsistencies particularly near inlets, shoals and irregular bathymetry. Trends in longshore transport rates, such as increases and decreases in gross transport rates are well represented by the WIS-derived potential transport rates. The discrepencies between the published field studies and WIS results are apparently primarily due to assumptions in the WIS model, such as assuming shore-parallel bathymetric contours.

In recent years oil and gas mining has moved into increasingly deeper water in search of undeveloped fields. As water depths approach and exceed 3000 m conventional offshore foundation systems become inefficient and ineffective in stabilising platforms and floating production storage units. The trend of supporting structure design in deep water has been to install catenary and taut leg mooring systems. Consequently, many types of anchoring systems are being developed and used in order to withstand large mooring forces. The SEPLA (Suction Embedded Plate Anchor) is ideal for use in this situation. This project has employed advanced numerical techniques and centrifuge testing to study pullout behaviour of plate anchor foundations in different soil profiles and suction caisson installation effect with the aim of generating a robust framework for design. The behaviour of strip and circular plate anchors during vertical pullout in uniform and normally consolidated clays has been studied by means of small strain and large deformation finite element analyses. Both fully bonded (attached), and ‘vented’ (no suction on rear face), anchors have been considered. The current numerical results were compared with existing laboratory test data, finite element results and analytical solutions. This study showed that the ultimate pullout capacity factors (Nc) for deep embedment were 11.6 and 11.7 for smooth and rough strip anchors and 13.1 and 13.7 for smooth and rough circular anchors respectively. When the anchor base was vented, the soil stayed attached to the anchor base for deep embedment, and the pullout capacity was therefore the same as for the attached anchor. The separation depth ratio, Hs/B or Hs/D was found to increase linearly with the normalised strength ratio, su/γ'B or su/γ'D. / Numerical simulation has been conducted to assess the bearing capacity for inclined pullout plate anchors. This bearing capacity analysis was performed by embedding the anchors in clay with different initial inclinations and different embedment ratios. Both the attached anchor base and vented base were evaluated. The results showed that the bearing capacities of the inclined plate anchors were associated with the inclination angles and base conditions. The separation depth of the plate anchors can be assessed by a simple equation from vertically pulled out plate anchors. Large deformation finite element analyses of plate anchor keying in clay has been performed. The effects of anchor thickness, anchor padeye eccentricity, anchor-soil interface roughness, soil shear strength, anchor submerged weight and soil disturbance have been studied with anchors in uniform or normally consolidated clays. The numerical results were compared with transparent soil test and existing centrifuge test data. The study showed that the RITSS method works well in simulating the anchor keying process. Anchor padeye eccentricity played an important role in anchor keying. A normalised anchor geometry ratio was used to estimate the loss in embedment during plate anchor’s keying. Both finite element analysis and centrifuge tests have been conducted to study the suction caisson installation effect. In finite element analysis, the soil disturbed zone varied from 3 times the caisson wall thickness to a full area inside a caisson. / Centrifuge tests of suction embedded plate anchors were conducted in normally consolidated kaolin clay and transparent uniform soil. It can be concluded that the reduction in anchor capacity due to soil disturbance after suction caisson installation depends on re-consolidation time and soil sensitivity. The soil disturbance also reduced the loss of embedment during the anchor keying process.

名古屋大学年代測定総合研究センターシンポジウム報告

Drilling operation expanded through deep water environments starting from mid-1980. As water depth increased, hydrate bearing formation in the shallow ocean floor is observed and that started to cause problems during drilling and production operations. Problems due to hydrate dissociation and forming during operations are also reported by the companies working in those environments many times. Although there are several factors affect the dissociation of shallow hydrate bearing sediments, heat flux from deeper sections of the well through shallower section during the operation is the major one. In order to mitigate that risk in this study, Black Sea is taken as a reference drilling environment. Hydrate phase boundary of the region is calculated via using actual temperature and pressure data gathered during drilling operations. Generic wellbore is defined and common drilling operation sequence is simulated in this defined wellbore. Heat transfer from section target depths to the shallow wellbore section is observed during simulations. Reducing effect of low inlet temperatures and a low circulation rate on wellbore temperatures are determined. In addition positive effect of riser boosting on depressing wellbore temperature in the well head is determined. Black Sea deep water hydrate stability zone is determined between 2210-2275m. Target depth limitation for generic well designed in drilling operations is determined as 4600m.

Dual Gradient Drilling (DGD) system is a promising technology that was developed to overcome the deep water drilling problems occurred due to narrow operating window between pore pressure and fracture pressure. In conventional drilling practice, single mud weight exists from drilling unit to TVD (True Vertical Depth) which creates big hydrostatic pressure in bottom hole ,moreover, minor changes in mud weight results a big pressure changes proportional to the length of hydrostatic column increase with water depth. On the other hand, DGD allows using two different mud weights to get same bottom hole pressure / low gradient drilling fluid from drilling unit to the sea floor and high gradient drilling fluid form the sea floor to TVD, to decrease the effect of water column on mud hydrostatic pressure in TVD. In this thesis, a conventionally drilled deepwater well was redesigned considering the DGD system and drilled virtually to determine the changes of cost of services and materials on total operation budget to prove the positive impact of system on total operation cost. This study not only proved the technical advantages of the DGD system, but also showed economical impact of the system on total drilling cost, by decreasing around 19%.

O crescimento acelerado da população idosa juntamente com o aumento da procura por atividades físicas tem motivado cada vez mais estudos que envolvam treinamento e o idoso. A corrida em piscina funda parece ser uma alternativa interessante para essa população, uma vez que não possui impacto nos membros inferiores possibilitando que o indivíduo se exercite em grandes cargas aeróbias com menor risco de lesão. Desta forma, o objetivo do presente estudo foi avaliar os efeitos de dois programas de treinamento em piscina funda nas respostas cardiorrespiratórias, neuromusculares e no equilíbrio de idosos. Participaram do estudo 34 sujeitos, divididos em um grupo que realizou um treinamento aeróbio de corrida em piscina funda (AERO; n=16; 66±4 anos) e um grupo que realizou um treinamento de força em meio aquático seguido do treinamento aeróbio de corrida em piscina funda (FOR-AERO; 64±4 anos). Ambos os grupos realizaram um período de familiarização com o meio aquático e com a técnica de corrida em piscina funda anteriormente ao período de treinamento, com duração de quatro semanas e com frequência semanal de duas sessões. Já o período de treinamento teve uma duração de 12 semanas realizando três sessões por semana. Antes e após ambos os períodos, os indivíduos foram avaliados em parâmetros relacionados à capacidade cardiorrespiratória, às respostas neuromusculares e ao equilíbrio. Para análise dos dados pré e pós-período de familiarização foi realizado um teste T pareado, para as comparações pré e pós-treinamento foi utilizado uma ANOVA para medidas repetidas com fator grupo ( =0,05). Em relação às variáveis cardiorrespiratórias e neuromusculares não foram observadas mudanças significativas após o período de familiarização. Entretanto, o equilíbrio em todas as situações avaliadas (apoio unipodal e bipodal com e sem venda nos olhos) apresentou uma melhora significativa após as quatro semanas de familiarização (p<0,05). Após o período de treinamento, ambos os grupos apresentaram uma redução da frequência cardíaca de repouso, um aumento do consumo de oxigênio de pico e um aumento do consumo de oxigênio no segundo (VO2LV2) e no primeiro limiar ventilatório (p<0,05). Somente o VO2LV2 apresentou diferença entre os grupos no pós-treinamento, demonstrando valores maiores para o grupo AERO (p<0,05). Em relação às variáveis neuromusculares, ambos os grupos aumentaram a força muscular dinâmica máxima e a força muscular isométrica de extensão de joelho após o treinamento (p<0,05), sem diferenças entre os grupos (p>0,05). A resistência muscular dinâmica apresentou um aumento significativo (p<0,05) tanto para flexão como para a extensão de joelho, sem diferença entre os grupos (p>0,05). A atividade eletromiográfica máxima apresentou um aumento significativo para os músculos vasto lateral, reto femoral e semitendinoso (p<0,05), sem diferenças entre os grupos (p>0,05). Em relação às repostas de equilíbrio, observamos uma manutenção dos valores em ambos os grupos após o período de treinamento (p>0,05). Assim, concluímos que os dois modelos de treinamento avaliados foram eficientes para melhoras significativas nas respostas cardiorrespiratórias e neuromusculares de homens idosos, e não foram específicos para melhoras nas respostas de equilíbrio. Entretanto, o período de familiarização proporcionou melhoras significativas no equilíbrio em todas as situações avaliadas. / The accelerated growth of the elderly population together with increased demand for physical activities has motivated more studies involving training and the elderly. The deep water running seems to be an interesting alternative for this population, since it does not have any impact on the lower limbs allowing the individual to exercise in high aerobic loads with less risk of injury. Thus, the aim of this study was to evaluate the effects of two deep water training programs on the cardiorespiratory, neuromuscular and balance responses in elderly. Thirty-four elderly men were placed into two groups: deep water aerobic training (AERO; n=16; 66±4 years); and deep water strength followed aerobic training (FOR-AERO; 64±4 years). Both groups performed four weeks of familiarization with the aquatic environment and with the deep water running technique prior to the training period, twice a week. On the other hand, the training period lasted 12 weeks, with three sessions a week. Before and after both periods, the subjects were evaluated on cardiorespiratory, neuromuscular and balance responses. Statistical comparisons in the familiarization period were performed by using paired T tests; and a repeat measure ANOVA with group factor was used to analyze the training-related effects ( =0,05). After the familiarization period, there were no significant differences in cardiorespiratory and neuromuscular variables. However, in all situations evaluated (one and two-legged standing with eyes opened and closed) the balance showed a significant decrease after four weeks of familiarization (p<0,05). After the training period, the heart rate at rest decreased significantly, the peak oxygen uptake and the oxygen uptake corresponding to the first and second ventilator threshold (VO2LV2) showed significant increases in both groups (p<0,05). Only the VO2LV2 showed differences among the groups after the training period, showing higher values for the AERO group (p<0,05). In addition, after training there was a significant increase in the knee extensors maximal dynamic strength and maximal isometric voluntary contraction in both groups (p<0,05), with no difference between groups (p>0,05). The dynamic muscular endurance showed a significant increase for both knee flexion and extension, with no difference between groups (p<0,05). There was a significant increase of the maximal isometric electromyography activity of vastus lateralis, rectus femoris and semitendinosus (p<0,05), with no difference between groups (p>0,05). Finally, after the training period the balance responses were unchanged (p>0,05). In summary, the two training models evaluated were effective for significant improvements in cardiorespiratory and neuromuscular responses in elderly men, and not specific to improvements in balance responses. However, the familiarization period improved significantly the balance in all situations evaluated.