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Tesis sobre el tema "Marine Transport"
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1
Leadbetter, Adam Marc. "Sediment transport in mixed marine environments." Thesis, University of East Anglia, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429678.
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Kahkeshan, Siavoche. "Marine log supply : a transport engineering analysis." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/27117.
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This thesis investigates the marine transport-inventory system of Coastal British Columbia.
The intrinsic characteristics of marine log transportation in this region are the vulnerability of marine transportation to adverse weather conditions and the presence of time-related economic costs.
The system is confined to the Powell River operation. Three origins, one storage area and three pulp log types are considered. The formulated problem is classified as a sequential decision-making process. A deterministic model using the network flow theory and a simulation model using GPSS are developed. Due to considerable uncertainty in the system operation, the computer simulation model is selected.
The model includes all of the important system variables and their interactions and assesses alternative operational doctrines by calculating variation in a key aspect of system performance, total logistic cost.
It is found that: 1) the use of barges as the transportation mode leads to the least logistic cost, 2) the second best transportation alternative is the direct shipment of logs from origins to the mill and 3) if higher value saw log is considered, the log-taxi alternative may become attractive.
However, to improve the capability of the developed model, more information on the salt contamination and teredo damage and accurate estimation of cost consequences of a mill shutdown are required. Future works should focus on these areas.<br>Applied Science, Faculty of<br>Civil Engineering, Department of<br>Graduate
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Miller, Jessica Adele. "Local and regional patterns of transport, dispersal, and exchange in coastal fishes /." view abstract or download file of text, 2004. http://wwwlib.umi.com/cr/uoregon/fullcit?p3136435.
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Thesis (Ph. D.)--University of Oregon, 2004.<br>Typescript. Includes vita and abstract. Includes bibliographical references (leaves 215-240). Also available for download via the World Wide Web; free to University of Oregon users.
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Garrill, Ashley. "Comparative studies of ion transport in marine fungi." Thesis, University of Liverpool, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303686.
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Davies, Julia Mary. "Ion transport in the marine fungus Dendyphiella salina." Thesis, University of Liverpool, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278904.
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BERTHET, CRISTELE. "Ecoulement et transport littoraux tridimensionnel : applications numeriques." Université Joseph Fourier (Grenoble), 1996. http://www.theses.fr/1996GRE10223.
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L'utilisation d'un modele numerique tridimensionnel a permis d'etudier d'une part un ecoulement caracteristique en zone cotiere a forte bathymetrie, d'autre part, le transport de sediment. L'influence de la bathymetrie et de la stratification sur l'evolution d'un courant et de la surface libre est analysee. Cette etude se concretise par une simulation realiste de la section du courant nord face a la baie de monaco. Le transport du sable et de la vase est considere sous l'action d'un courant et de la houle. Puis, une etude sur le transport des particules organique permet d'evaluer la production primaire dans la colonne d'eau
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Silva, Arnold Lawrence. "Effect of salinity on integumental transport in marine bivalves." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185863.
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The transport of organic solutes from sea water by the molluscan integument occurs via a Na⁺-dependent cotransport process. Although much is known about the mechanism of this transport, little attention has been given to the influence of environmental parameters on this process. One highly variable parameter to intertidal animals is salinity. Intertidal habitats are routinely exposed to periodic changes in external salinity from ∼0 to ∼425 mM Na⁺, representing a range of ∼0 to ∼1000 mOsM osmotic concentration. This study examined the effect of salinity on organic solute transport and cell volume regulation in the gill of two representative intertidal animals, Mytilus edulis and Mytilus californianus. Integumental organic solute transport was found to adapt to reduced salinity in a 2-stage response. There was an initial, steep inhibition of transport that was far greater than predicted from the reduction of external Na⁺ alone. However, within 10 min. of acclimation to the dilute medium, transport recovered to the level predicted by the external Na⁺ concentration. Long-term acclimation to reduced salinity resulted in no upregulation of integumental transport. Thus, the degree of adaptation of integumental organic solute to reduced external salinity was always defined by the availability of external Na⁺ for the transport process. The exposure to reduced salinity also resulted in a change of cell volume. The gill preferentially lost organic solutes but spared inorganic ions following long-term acclimation to reduced salinity. Short-term acclimation of gill tissue to reduced salinity resulted in a rapid Volume Regulatory Decrease (VRD) which served to restore cell volume toward the control value. This short-term VRD did not involve the substantial loss of organic solutes, but was probably mediated by the efflux of K⁺ (and a counter anion) across the basolateral membrane. The loss of inorganic ions during brief exposures to reduced salinity conserves metabolically expensive organic compounds. The loss of organic solutes during long-term acclimation to reduced salinity may be due to the decreased Na⁺ gradient which reduces the ability of integumental transport to maintain the high solute concentrations in gill tissue of control animals.
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Salter, David Jerome. "Leadership styles in United States Marine Corps transport helicopter squadrons." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/27118.
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Antunes, Filipa Alexandra Paiva. "Ship transport of marine invasive species and its stress resistance." Master's thesis, Universidade de Évora, 2014. http://hdl.handle.net/10174/12339.
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In the context of biological invasions, ship transport plays an important role in the transference of species around the world. During this process organisms are exposed to several stressful conditions, which do not prevent them to arrive in areas where they did not occur before. The marine invertebrates Carcinus maenas and Mytilus galloprovincialis natives in Portugal, have already established stable invasive populations in several regions worldwide. This study exposed organisms of both species to stress conditions similar to what occurs in ballast tanks and on ship hulls. Results showed a high survival of pre-stressed Mytilus galloprovincialis individuals when compared to non pre-stressed organisms when exposed to air exposure, hyposalinity and heat events. However when Carcinus maenas was exposed to heat stress, there was no significant difference between groups with a different stress history. These findings suggest that transport on ships is not only a vector of dispersal but also a vector capable to increase the resistance to stress conditions in potential species invaders by selection of resistant individual; Resumo:
"Transporte marítimo de espécies marinhas invasoras e sua resistência ao stress"
No contexto das invasões biológicas, o transporte marítimo desempenha um papel importante contribuindo para a transferência de espécies em todo o mundo. Durante este processo os organismos são expostos a variadas condições de stress que não os impede de chegar a áreas onde não ocorriam anteriormente. Os invertebrados marinhos Carcinus maenas e Mytilus galloprovincialis nativos em Portugal, já estabeleceram populações invasoras estáveis em várias regiões do mundo. Neste estudo, submeteram-se organismos de Carcinus maenas e Mytilus galloprovincialis a condições de stress semelhante ao que ocorre em tanques de água de lastro e em cascos de navios. Os resultados mostram uma maior sobrevivência dos indivíduos Mytilus galloprovincialis pré – expostos a condições de stress quando comparado com organismos sem uma prévia exposição a esses eventos de stress, quando expostos ao ar, baixa salinidade e altas temperaturas. No entanto, quando Carcinus maenas foi exposto a temperaturas mais altas, não houve diferença significativa entre os grupos com diferentes exposições ao stress aplicado. Estes resultados sugerem que o transporte marítimo não é apenas um vetor de dispersão mas também um vector capaz de aumentar a resistência a condições de stress em potenciais espécies invasoras, nomeadamente através da seleção dos indivíduos mais resistentes.
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Maldonado-Pareja, Maria Teresa. "Iron acquisition by marine phytoplankton." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0022/NQ50215.pdf.
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Granger, Julie. "Iron acquisition by heterotrophic marine bacteria." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0002/MQ44173.pdf.
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Hudson, Jeanna M. "Myctophid Feeding Ecology and Carbon Transport along the Northern Mid-Atlantic Ridge." W&M ScholarWorks, 2012. https://scholarworks.wm.edu/etd/1539617916.
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The Mid-Atlantic Ridge (MAR) is the largest topographic feature in the Atlantic Ocean, yet little is known about the food web structure and trophic ecology of fishes inhabiting mesopelagic waters along the MAR. To better understand the food web structure and to compare the feeding ecology of abundant MAR fishes to those in offridge areas, MAR-ECO, a Mid-Atlantic Ridge ecosystem field project of the Census of Marine Life, sampled the pelagic fauna of the northern MAR (Iceland to the Azores) during June-July, 2004. Samples were collected with two midwater trawls outfitted with multiple opening and closing cod ends to sample discrete depths from the surface to >2300 m at predefined stations within four ridge sections. Fishes of the family Myctophidae were the most abundant fishes collected, with the myctophid Benthosema glaciale the numerically dominant species. The feeding ecology of three myctophid species, B. glaciale, Protomyctophum arcticum, and Hygophum hygomii, were quantified through dietary analysis. Each species was predominantly zooplanktivorous, consuming copepods, euphausiids, ostracods, and other crustacean zooplankton, with each myctophid species exhibiting unique dietary patterns. Different abiotic parameters influenced variability in the diet of B. glaciale and P. arcticum as determined by canonical correspondence analysis. Of the measured parameters, ridge section and time of day were significant explanatory variables in the diet of B. glaciale, while only depth was significant in the diet of P. arcticum. Daily consumption by B. glaciale and P. arcticum was highest at the Reykjanes Ridge and Charlie-Gibbs Fracture Zone, respectively; consumption by H. hygomii was only measured at the Azorean Zone. Daily consumption of all three species was less than 1% of dry body weight. Active transport of carbon out of the euphotic zone by diel vertically migrating MAR myctophids through respiration of CO2, excretion of dissolved organic carbon, and egestion of particulate organic carbon (POC) was also estimated, and compared to passive sinking of POC in the North Atlantic. Active carbon flux by the 0-200 m integrated migrant myctophid biomass, uncorrected for trawl efficiency, ranged from 0.01-0.4% of sinking POC flux at 150 m and 0.02-0.95% at 300 m. If myctophid biomass was corrected for low gear efficiency, flux increased to 0.1-1% and 0.3-3.5%, respectively, of sinking POC. Lower MAR myctophid biomass resulted in lower active carbon transport compared to myctophids in the Pacific and zooplankton in the North Atlantic estimated in previous studies, but myctophid active transport should still be considered in models of MAR carbon cycling. Due to the role of myctophids as both predators of numerous zooplankton taxa and as prey of higher taxa, information on the feeding ecology and daily consumption of these fishes is necessary to accurately assess their role in the MAR food web and the overall trophic structure of this hydrodynamically and topographically unique ecosystem.
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Veldhuis, Ivo. "Application of hydrogen marine systems in high-speed sea container transport." Thesis, University of Southampton, 2007. https://eprints.soton.ac.uk/51284/.
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Conventional marine fuels have always limited the endurance of high-speed ships leading to fast but inefficient cargo ships. This research considers the fuel weight barrier in high-speed ship design and the use of hydrogen as a marine fuel to overcome this barrier. Simultaneously, it is now accepted that environmental pollution from ships, particularly large containerships, contributes to climate change. Hydrogen marine utilization provides a solution for both. As common to other hydrogen research the fuel system spans production to utilization. This hydrogen marine system utilizes an established production method to obtain hydrogen from natural gas through steam methane reformation. To achieve an acceptable storage volume meeting the typical highspeed ship dimensions the hydrogen also requires liquefaction. The hydrogen is then converted onboard into shaft power via combustion in aero-derivative gas turbines. This research establishes the necessary system components spanning both onshore and ship components. The novelty of the research has resulted in new design tools. Research into large hydrogen transport applications is not new and a substantial body of research is available from passenger aviation studies performed during the 1980s and 1990s. Additionally, a more current body of research is available describing hydrogen utilization in large gas turbines for energy and oil/gas industries. This combined research provides the characteristics of the onboard hydrogen system of a high-speed foil-assisted containership. This ship is capable of transporting 600 industry standard 20’ containers on long-haul ocean routes, i.e. 5000 nautical miles, at a speed of 64 knots (118.5 km/hr). Such ship performance is not feasible with conventional marine fuels. The design is complex involving a combination of buoyancy and dynamic lift and two distinct operational modes at floating and dynamic draughts. Research involving this ship configuration is included here in conjuction with suitable design methodologies. Besides technical feasibility, economic feasibility of this containership has also been investigated based around the unit transport price required to recoup costs and achieve zero net present value. Such analysis identified that the containership has higher minimum freight rates than conventional containerships but substantially lower rates than aviation cargo. Due to its high-speed and improved endurance it can compete with aviation on transport time and price. Economic review also identified that shorter container door-to-door times are now demanded by the consumer production industry and this hydrogen marine container transport system meets this demand.
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Kader, Ab Saman Abd. "Cost modelling for inland waterway transport systems." Thesis, Liverpool John Moores University, 1997. http://researchonline.ljmu.ac.uk/5576/.
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Inland waterways have proven to be a significant mode of infrastructure for the carriage of freight. Examples of this can be seen in many developed regions such as Continental Europe, the United States of America and to a lesser extent, the United Kingdom. The benefit resulting from the existence of waterways are enormous in both transportational and non-transportational benefits. Hence there are considerable benefits which will result from a sustained development of waterways. This study identifies all relevant parameters associated with the waterways system. They include the waterway route, the barge provision to carry the cargo and terminal facilities as an interface point for cargo handling operations. Methods have been determined to enable various costs to be estimated. This estimating procedure can be very useful for a preliminary evaluation of development proposals pending a more detailed cost analysis. Estimated benefits can also be quantified at this preliminary stage. Data has been collected from a number of reliable sources. Models have successfully been generated and each model has been validated to an acceptable level of accuracy. The analysis has been applied to a proposed development of an inland waterway transportation system in the Klang Valley region of Malaysia. The results indicate viability for the scheme and, moreover, show the degree to which designers and planners can benefit from the use of the models.
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Zainescu, Florin Iulian. "Fluvio-marine interactions and sediment dynamics in river mouth areas." Thesis, Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0697.
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Cette thèse s’est construite autour du fait établi que la zone d’embouchure a joué un rôle central dans le développement du delta du Danube et de l’hypothèse selon laquelle les embouchures, étant des pourvoyeurs pour la côte en sédiments et en eau douce, sont essentielles à la compréhension des côtes sous influence d’embouchures. Cette thèse est basée sur des données de terrain, notamment des levés bathymétriques, des mesures de débit fluvial et de décharge sédimentaire, des données de vagues, vents et courants, ainsi que des profils topographiques et des images satellites. Une grande partie de cette thèse est consacrée à l’utilisation de Mike 21/3 by DHI (Danish Hydraulic Institute), un modèle couplant hydrodynamique et vagues. Les résultats montrent une réponse linéaire dans les changements bathymétriques en relation avec l’influence des inondations et des tempêtes, ces changements peuvent être prédits par un index innondation/tempète basé sur le débit fluvial, la décharge sédimentaire et la hauteur des vagues (R^2=0.84). Des simulations de modélisation exploratoire sont développée pour une gamme complète de conditions. La déflexion du jet est prédit en fonction de l’équilibre entre débit fluvial et courant longshore, ainsi le jet sortant est dévié (ou non-dévié) quand le courant longshore est dominant (ou dominé) sur le débit fluvial. Finalement, la thèse esquisse un schéma préliminaire du transport sédimentaire sur le lobe deltaïque de l’embouchure St. Gheorghe et décrit les actions nécessaires pour envisager au complet le système de transport sédimentaire, indispensable à une gestion réussie de cette côte deltaïque<br>This thesis started from the observation that river mouths play a central role in the development of the Danube Delta and from an intuition that river mouths, as suppliers of sediment and water to coastal areas are quintesential in understanding river-influenced coasts. The present thesis is based on field data which comprises bathymetric surveys, measured river water and solid discharges, wave and wind data, ADCP data, topographic profiles, satellite imagery. Also, a big part of the thesis is dedicated to using the Mike 21/3 by DHI (Danish Hydraulic Institute), a coupled hydrodynamic and wave model.Results show a linear response in bathymetric change in relation to the relative influence of floods and storms and that change can be predicted by a Flood/Storm index based on river water or sediment discharge and wave height proxies (R^2=0.84). Furthermore, the analysis is extended using exploratory modelling to a full range of conditions. Jet deflection is predicted by a balance of river jet discharge and longshore current discharge, such that the jet is deflected (undeflected) when the longshore current is much higher (much lower) than the river jet, and a ~45* deflection is predicted when the discharge of jet equals the discharge of the longshore current.Finally, the thesis sketches a preliminary scheme for the sediment transport at the wave-influenced Sf. Gheorghe lobe, taking into account the known sources and sinks, based on bathymetric measurements and numerical modelling results; and outlines the actions needed to envisage a full sediment transport scheme which is needed for a successful management of the deltaic coast
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Venkatraman, Padma T. "Persistent organic pollutant transport and fate: Assessment by molecular tracers." W&M ScholarWorks, 2001. https://scholarworks.wm.edu/etd/1539616891.
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Persistent organic pollutants (POPs) such as the organochlorine pesticide hexachlorocyclohexane (HCH) may undergo atmospheric transport and accumulate in regions remote from the source. It is important to develop techniques to help apportion source and identify transport or transformation processes to which HCHs and other mobile POPs may be subjected. Molecular tracers such as compound specific stable isotope and enantiomer ratios (ERs) may prove valuable in studying POP fate and transport. The objective of this study was to further develop the use of these two novel geochemical tools to evaluate the sources, transport and environmental fate of POPs, in the context of studying the fate and transport of HCH, a globally distributed POP. In the first part of my study, I evaluated the potential for using stable isotope ratios to track POP source and transport, using HCH in laboratory simulations of global distillation. I compared the relative fractionation of carbon versus deuterium isotopes during air-water gas exchange along a strong temperature gradient. The hypothesis, that perdeuterated, but not necessarily carbon-labeled compounds would show measurable and significant fractionation during air-water transfer, was validated within the confines of the experimental system. The results suggest that it may be possible to use a dual tracer approach on a larger scale, in which carbon isotopes could be used to track POP source, while fractionation of deuterium may be used to track POP transport distance. In the second part of the study, I evaluated the potential for use of ERs to evaluate HCH biodegradation. The rationale was that most enzymatic processes are stereoselective, enantiomers of pesticides may microbially degrade at significantly different rates, leading to increased environmental persistence of the non-degradable isomer. to bridge the gap between microbial and chemical information on enantioselective processes, I measured microbial activity, abundance, concentrations and enantiomer ratios of HCH in air and surface waters of the York River estuary. HCH concentrations and ERs were related with microbial activity but there were seasonal variations in enantioselectivity suggesting that seasonal as well as spatial differences in microbial communities may affect HCH ERs. The relationship between microbial parameters and enantioselective degradation appears to be complex and warrants further study before ERs can be used as effective tracers of chiral POP transport.
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Shannon, Lynne Jane. "Modelling the oceanographic transport of young Cape anchovy Engraulis capensis by advective processes off South Africa." Master's thesis, University of Cape Town, 1995. http://hdl.handle.net/11427/21784.
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Bibliography: pages 107-121.<br>A Monte-Carlo type model has been developed to investigate the importance of passive transport by currents above the thermocline for anchovy recruitment off South Africa. Simulation studies indicate that mean year-class strength of Cape anchovy is relatively robust to altered advective processes off South Africa. This occurs despite the fact that changed flow alters the likelihood of offshore advection and hence losses of anchovy from the system. Two different approaches have been taken to address the effects of altered advection, and the applicability of each is discussed. One approach involves altering westward advection in proportion to the mean current field (derived from Acoustic Doppler Current Profiler measurements), and the other, altering westward and northward advection by the addition of fixed offshore current velocities. The proportional approach did not affect year-class strength significantly, whereas the other approach, which incorporated large changes in the flow field, yielded statistically significant differences in predicted year-class strengths between advection scenarios. Reduced flow in the latter approach led to a mean year-class strength 2.7 times stronger than a proposed base flow scenario (which incorporated westward and northward drift in addition to the ADCP currents), whereas enhanced flow resulted in a mean year-class strength of similar magnitude to that of the base flow scenario. Changed flow may alter the geographic distribution of eggs and larvae, which might in turn influence recruitment of young-of-the-year anchovy to the South African purse-seine fishery. The north-flowing shelf-edge jet current plays an important role in transporting anchovy eggs and larvae from spawning grounds in the south to nursery areas frn1her north along the west coast of South Africa. Enhanced model advection westward and norward from the spawning grounds in the south serves to transport anchovy into the region of the jet current. However, advection into unproductive waters offshore is also enhanced and prevents good recruitment under these flow conditions. On the other hand, reduced westward and northward advection in the model, shown through wind records to characterise El-Nino years in coastal areas of South Africa, serves to retain anchovy reproductive products and often transports young anchovy into coastal areas, preventing offshore loss. Therefore the advection model suggests that good year-class strengths (in terms of numbers) are likely to be supported in years when westward and northward advection are reduced. A further reduction in westward advection may be less favourable by causing advective losses offshore along the south coast of South Africa. This may be viewed in terms of an "optimal environmental window" hypothesis, where reduced westward advection is favourable for anchovy survival off South Africa, but further reduction of westward advection as well as enhanced westward advection appear unfavourable. It is concluded that although passive transport, of anchovy in South African waters is relatively robust, it may account for a substantial proportion of recruitment variability.
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Karle, Ida-Maja. "On redox reactions and transport processes of solutes in coastal marine sediments /." [Göteborg] : Analystical and Marine Chemistry, Dept. of Chemistry, Göteborg University, 2006. http://www.loc.gov/catdir/toc/fy0706/2006455268.html.
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Carr, Sarah Luettich Richard A. "The influence of vertical migratory behaviors on the transport of marine organisms." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,396.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2006.<br>Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Marine Sciences." Discipline: Marine Sciences; Department/School: Marine Sciences.
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馮秀琼 and Sau-king Fung. "Recreation public transport planning for country and marine parks in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B31261061.
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Nodwell, Lisa M. "Inorganic colloidal iron use by marine mixotrophic phytoplankton." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=30826.
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Three species of photosynthetic flagellates capable of phagotrophy (mixotrophic species) were tested for their abilities to use inorganic iron colloids for growth. Ochromonas sp., Chrysochromulina ericina (a coastal strain) and C. ericina (an oceanic strain) were grown in iron-free seawater supplemented with 1 muM goethite, hematite, magnetite/maghemite or ferrihydrite (90°) in the presence and absence of desferrioxamme B, an iron-binding siderophore. Both strains of Chrysochromulina grew at 35--70% of their maximum rates with goethite, hematite, and magnetite/maghemite, but were unable to use ferrihydrite. Ochromonas, however, grew well with ferrihydrite, but could not use any of the other forms. All the flagellates were able to acquire iron from ingested bacteria. Diatoms that were known only to take up dissolved forms of iron, Thalassiosira oceanica (clone 1003) and T. pseudonana (clone 3H), were unable to use any of the colloids tested. The mechanism of iron acquisition by the flagellates appeared to involve ingestion of the iron colloids as DFB had no effect on colloidal iron availability and bacteria resident in the cultures were unable to use the iron contained in the colloids. Variations in the size of the colloids were hypothesized to account for differences in their availability, independent of colloid chemical stability. The results provide the first strong evidence for direct utilization (i.e. without prior dissolution) of colloidal iron by mixotrophic phytoplankton and document a new pathway of iron acquisition that may be important for their survival in low-iron waters of the sea.
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Wilson, Stephanie E. "Mesopelagic zooplankton feeding ecology and effects on particle repackaging and carbon transport in the subtropical and subarctic North Pacific Ocean." W&M ScholarWorks, 2008. http://www.vims.edu/library/Theses/Wilson08.pdf.
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Guerra, Josefa Varela. "Interannual variability of nearbed sediment flux and associated physical processes on the Eel River shelf, Northern California, USA /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/11000.
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Wren, Patricia Ansley. "Sediment transport measurements on the mid-continental shelf in Onslow Bay, NC." NCSU, 2004. http://www.lib.ncsu.edu/theses/available/etd-03152004-100655/.
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Long-term in situ measurements have been made on the mid-continental shelf in Onslow Bay, NC to determine the frequency and direction of bottom sediment movement and the processes responsible for bottom sediment motion. As part of the Coastal Ocean Research and Monitoring Program (CORMP) at the University of North Carolina at Wilmington, a quadrapod frame with a downward looking Pulse-Coherent Acoustic Doppler Profiler (PC-ADP) and an upward looking Acoustic Doppler Current Profiler (ADCP) has been maintained on the continental shelf at approximately 30 m depth since May of 2000. The instruments are moored 27 nautical miles off the coast of Wilmington, North Carolina in Onslow Bay, adjacent to a productive marine hardbottom. Simultaneous measurements of flow velocities from the surface to the seabed, along with acoustic backscatter measurements, have been obtained. Measurements of seabed elevation, temperature, conductivity, and pressure were also collected at the site. Bed stresses due to wave-current interactions are calculated using a bottom boundary layer model (Styles and Glenn, 2002). Wave-current interactions resulted in shear stresses at the sediment-water interface that exceeded the critical threshold for sediment movement over 50% of the time during a climatological average year. Sediment transport was been shown to occur during four different types of events at the site: 1) small to moderate northerly wind events 2) Gulf Stream Intrusion events 3) strong southerly wind events associated with the passage of frontal systems 4) the passage of tropical storm systems. Over the course of a year the total net suspended sediment flux at 1 mab was in the positive along-shelf direction (southwest) and in the negative across-shelf direction (onshore), where there was several times more net transport in the onshore direction than the along-shelf direction. Three mechanisms leading to significant sediment transport on the mid-continental shelf have been indentified: 1) wave-current interactions 2) subtidal currents associated with sustained wind-driven flows and the intrusion of Gulf Stream water on the shelf 3) infragravity waves. Subtidal currents played a key role in the sediment transport during all types of events. Wind driven subtidal currents were important in determining the magnitude and direction of sediment transport during storm events, while subtidal currents associated with a Gulf Stream intrusion event combined with fair-weather swell resulted in accretion at the site of 3 cm over a three week period. The results show that a moderate northeasterly wind event with sufficient duration to generate wind driven subtidal flows resulted in an order of magnitude more sediment transport (20,237 g cm<sup>?2</sup>) than a similar northerly wind event and the southerly wind event without developed wind?driven flows. These two events resulted in similar amounts of sediment transport of 3,600 g cm<sup>?2</sup> and 3,061 g cm<sup>?2</sup>, respectively. The passage of a hurricane resulted in an order of magnitude more sediment transport than the moderate northeasterly wind event, on the order of 240,000 g cm<sup>?2</sup>. Shear velocities during the passage of Hurricane Isabel resulted in the largest bed shear stresses (~300 dynes cm<sup>?2</sup>) on record. Field measurements in the bottom boundary layer were compared with the bblm generated current profiles during moderate wind events and Hurricane Isabel. In addition, the suspended sediment concentration profiles from the model were compared with the ABS profile measurements to verify shape and magnitude as the storms increased and waned. In general, there was good agreement between the measured and model derived current profiles, and between suspended sediment measurements and the model concentration profiles for both large and small-scale events that occurred at the site.
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Bodolus, Deborah A. "Mechanisms of larval spot transport and recruitment to the Chesapeake Bay." W&M ScholarWorks, 1994. https://scholarworks.wm.edu/etd/1539616574.
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The spot (Leiostomus xanthurus) is an important commercial and recreational species in Virginia. Recruitment of juveniles to the Bay is characterized by large interannual fluctuations, that can be explained by the sequence and direction of wind during various phases of the early life history. An environmentally-modified Ricker stock-recruitment curve was developed incorporating the southeasterly winds in November-December, the southerly winds in January-March, and the westerly winds in April-May. This model explained 81% of the variation and closely paralleled the VIMS Juvenile Spot Index. Spot from the Chesapeake Bay migrate south in fall to spawn near or south of Cape Hatteras. Larvae were distributed over the shelf south of Oregon Inlet in February and early March, with the youngest larvae found over the outer shelf off Cape Hatteras. By late March, spot were distributed over the inner shelf north of Oregon Inlet to the mouth of the Chesapeake Bay. Age and size of larvae increased in a northward and shoreward direction. The persistence of larvae over the inner shelf north of Oregon Inlet suggests that a mechanism for northward transport occurs in this area. Northward transport over the inner shelf in the southern MAB is possible with multiple southerly wind events. Spot larvae would not have to be transported the entire distance to the Chesapeake Bay entrance, but only to where the bottom layers of the water column are moving toward the Bay. Recruitment to the Chesapeake Bay began in February or March of 1990 and in April of 1989 and lasted for two months. Spot entering the Bay were approximately 84 days old and 14.0 mm SL. The birthdates of spot collected offshore in the southern MAB and those at the Bay mouth were very similar, suggesting that recruits to the Bay were from the same pool of larvae collected earlier in the season and providing further support for a spawning location south of Cape Hatteras and not off the Chesapeake Bay as previously reported.
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Githachuri, Kung'u. "Influences on the transport properties of a range of South African marine concretes." Master's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/10499.
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Includes bibliographical references (leaves 183-184).<br>It is widely understood that the transport properties of marine concretes affect their potential durability in their service environment. The critical deterioration effect on such concretes is corrosion of embedded steel promoted by chloride ion ingress into the concrete. The occurrence of such deterioration and the rate at which it occurs depends on the quality of concrete, the aggressiveness of the particular marine environment and the coupling between the two. This dissertation presents the results of an experimental study done to compare different South African marine concrete making materials sourced from Cape Town, Port Elizabeth and Durban. The materials are typically specified for reinforced concrete structures in these urban marine regions.
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Meyer, Sebastian. "Aspects of the law and practice relating to transport documents in marine trade." Thesis, Swansea University, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678605.
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This research concerns carriage of goods by sea, in particular the law relating to bills of lading and transport documents. It concentrates on the relationship between the legal position and the position of the industry and practice within the field.
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Brink, Laura Ann. "Cross-shelf transport of planktonic larvae of inner shelf benthic invertebrates." Thesis, Thesis (M.S.)--University of Oregon, 1996, 1997. http://hdl.handle.net/1794/10073.
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Coronel, Carrera Abigail Lisbeth, and Arroyo Patricia Rossmary Loo. "Factores por las cuales los agroexportadores dejaron de embarcar carga refrigerada por el puerto General San Martin en Pisco." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/628029.
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En el presente trabajo de investigación tiene como objetivo dar a conocer los Factores por las cuales los agroexportadores dejaron de embarcar carga refrigerada por el puerto General San Martin en Pisco, y validar si con un buen planeamiento e inversión que se está dando favorecerá para que el puerto de Pisco sea una alternativa eficiente para los exportadores de productos agrícolas con el fin de facilitar su proceso de exportación evitando demoras en el traslado desde las plantas que se encuentran mayormente en Pisco, Chincha, Ica, Arequipa y lugares del Centro y Sur; hasta el puerto del Callao, como es de conocimiento nuestro puerto principal de mayor movimiento de cargas de exportación e importación se realiza en el puerto del Callao donde nos enfrentamos al congestionamiento que hay cada día.
En el primer capítulo contiene el marco conceptual donde abordamos temas de terminal portuario, como es la competitividad portuaria, el desempeño portuario, competitividad portuaria. Además, se detalla cómo es la ubicación geográfica en el puerto General San Martin de Pisco, la productividad, transporte y el flete. En el segundo capítulo, se ha desarrollado la metodología de investigación cualitativa, se ha definido los segmentos y categoría. En el tercer capítulo contiene los hallazgos de la investigación barreras y brechas que se han presentado durante el presente trabajo. Y por último en el cuarto capítulo, contiene las críticas de cada segmento y el análisis de lo recopilado en las entrevistas. Además, se ha definido las conclusiones y recomendaciones para la mejoría del puerto General San Martin.<br>In the present research work, the objective is to raise awareness of the Factors by which the agro-exporters stopped shipping refrigerated cargo through the General San Martin port in Pisco, and validate whether with a good planning and investment that is being given it will favor so that the Pisco port is an efficient alternative for exporters of agricultural products in order to facilitate their export process avoiding delays in the transfer from the plants that are mostly in Pisco, Chincha, Ica, Arequipa and places in the Center and South; to the port of Callao, as is known, our main port with the greatest movement of export and import loads is carried out in the port of Callao, where we face the daily congestion.
In the first chapter it contains the conceptual framework where we address issues of port terminal, port competitiveness, port performance. In addition, the geographical location in the General San Martin port, productivity, transport and freight are detailed. In the second chapter, the qualitative research methodology has been developed, the segments and categories have been defined. In the third chapter it contains the research findings, barriers and gaps that have been presented during the present work. And finally in the fourth chapter, it contains the criticisms of each segment and the analysis of what was collected in the interviews. In addition, the conclusions and recommendations for the improvement of the General San Martin port have been defined.<br>Tesis
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Palinkas, Cynthia. "Temporal and spatial patterns of modern shelf sedimentation in the Adriatic Sea /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/10986.
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Mullenbach, Beth Lee. "Characterization of modern off-shelf sediment export on the Eel margin, Northern California /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/10969.
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Mansui, Jérémy. "Observation et modélisation des macro-déchets en mer Méditerranée, de la large échelle aux échelles côtière et littorale." Thesis, Toulon, 2015. http://www.theses.fr/2015TOUL0015/document.
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L'objectif général de cette thèse est d'étudier les mécanismes de transport des déchets marins flottants ainsi queleur accumulation potentielle en Méditerranée, en s'appuyant sur la modélisation numérique de leur dérive ainsique sur des observations in-situ de leur distribution. La dynamique du transport des déchets marins y estnotamment analysée en terme d'échelles caractéristiques du bassin, en partant de la grande échelle jusqu'auxéchelles côtière et littorale.Dans un premier temps, l'examen d'un ensemble d'expériences Lagrangiennes numériques a permis d'identifierdans le bassin des zones probables d'accumulation non permanentes à grande échelle (Mansui et al., 2015a).L'impact à l'échelle côtière d'un courant de bord (Courant Nord) et des forçages atmosphériques sur ladistribution locale et l'échouage des déchets marins flottants a ensuite pu être estimé en utilisant notammentdes données originales recueillies en mer et à terre (Mansui et al., 2015b, en révision)<br>The main objective of this work is to study the floating marine debris transport mechanisms and their potentialaccumulation in the Mediterranean Sea, using numerical modelling and in-situ observations of debris. Thetransport dynamics is analysed in terms of typical scales in the basin, from the large scale to the coastal andlocal scales.First, the analysis of a Lagrangian experience data set show the potential existence of non-permanent and largeretention areas (Mansui et al., 2015a). In a second stage, the coastal impact of a boundary current (the NorthernCurrent) and atmospheric forcings on the local distribution and stranding of floating marine litter has beenestimated (Mansui et al., 2015b, under revision), using an original set of data combining offshore sightings andbeaching surveys
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Adly, Carol. "The role of iron in the ecology and physiology of marine bacteria /." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97884.
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Despite being abundant in the earth's crust, the concentration of Fe in many oceanic regions is so low that it is limiting to the growth of photosynthetic plankton. Heterotrophic bacteria play key roles in the oceanic cycling of carbon and nutrients, but it is unclear whether they can be Fe-deficient in nature, or what possible effects Fe-deficiency might have on their ecology and physiology. In chapter 1, I investigated the response of a natural bacterial community to a mesoscale Fe-enrichment experiment in the northeast subarctic Pacific. The addition of Fe to surface waters caused a rapid stimulation of bacterial growth and production, and induced the organic Fe uptake systems of bacteria. These findings suggest that bacteria responded directly to increased Fe availability, and may be Fe-deficient in situ. In chapter 2, I examined the effects of Fe-deficiency on the coupled processes of carbon catabolism and adenosine triphosphate (ATP) production in cultures of the marine bacterium Pseudoalteromonas haloplanktis. In Fe-limited cells, Fe-dependent oxidative pathways of ATP production were downregulated, leading to an intracellular energy deficit. Thus, by altering carbon metabolism and energy acquisition of heterotrophic bacteria, Fe may affect the cycling of carbon in parts of the sea.
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Horvath, Michele A. "Effects of Spot (Leisostomus xanthurus) Induced Bioturbation and Suspension on the Transport and Fate of Sediments and a Particle-Associated Organic Contaminant." W&M ScholarWorks, 1997. https://scholarworks.wm.edu/etd/1539617721.
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Fuhlbrügge, Steffen [Verfasser]. "Meteorological constraints on marine atmospheric halocarbons and their transport to the free troposphere / Steffen Fuhlbrügge." Kiel : Universitätsbibliothek Kiel, 2016. http://d-nb.info/1094661899/34.
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Corell, Hanna. "Applications of ocean transport modelling." Doctoral thesis, Stockholms universitet, Meteorologiska institutionen (MISU), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-75344.
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The advective motion of seawater governs the transport of almost everything, animate or inanimate, present in the ocean and those lacking the ability to outswim the currents have to follow the flow. This makes modelling of advective ocean transports a powerful tool in various fields of science where a displacement of something over time is studied. The present thesis comprises four different applications of ocean-transport modelling, ranging from large-scale heat transports to the dispersion of juvenile marine organisms. The aim has been to adapt the method not only to the object of study, but also to the available model-data sets and in situ-observations. The first application in the thesis is a study of the oceanic heat transport. It illustrates the importance of wind forcing for not only the heat transport from the Indian to the Atlantic Ocean, but also for the net northward transport of heat in the Atlantic. In the next study focus is on the particle-transport differences between an open and a semi-enclosed coastal area on the Swedish coast of the Baltic Sea. The modelled patterns of sedimentation and residence times in the two basins are examined after particles having been released from a number of prescribed point sources. In the two final studies the transport-modelling framework is applied within a marine-ecology context and the transported entities are larvae of some Scandinavian sessile and sedentary species and non-commercial fishes (e.g. the bay barnacle, the blue mussel, the shore crab and the gobies). The effects of depth distribution of dispersing larvae on the efficiency of the Marine Protected Areas in the Baltic Sea are examined. Further, the diversity in dispersal and connectivity depending on vertical behaviour is modelled for regions with different tidal regimes in the North Sea, the Skagerrak and the Kattegat. The spatial scales dealt with in the studies varied from global to a highly resolved 182-metres grid. The model results, excepting those from the global study, are based on or compared with in situ-data.<br><p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Submitted. 4: Manuscript.</p>
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Gallouët, Emmanuelle. "Le transport maritime de stupéfiants." Thesis, Aix-Marseille 3, 2011. http://www.theses.fr/2011AIX32103.
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Dans les années 1970, le trafic de stupéfiants a connu une rapide expansion, et n’a cessé, depuis, de s’accroître pour se mondialiser dans les années 1990 et atteindre une dimension géopolitique.De grands axes maritimes d’acheminement des différentes drogues exploités par les grandes organisations criminelles sont apparus, et il est devenu évident que les mesures qui permettent au secteur maritime de contribuer au développement des échanges mondiaux, et donc à la prospérité économique, l’ont rendu particulièrement propice au développement de ce type de trafic.Face à l’importance de la menace que constitue le transport maritime de stupéfiants, les Etats ont pris conscience de la nécessité d’en étendre et d’en rationaliser la répression à l’échelon international.Avec le temps, plusieurs conventions internationales, toujours en vigueur, ont vu le jour, sous l’égide des Nations Unies. La dernière en date, la Convention contre le trafic illicite de stupéfiants et des substances psychotropes, signée à Vienne en 1988, détermine, dans son article 17, le cadre de l’arraisonnement des navires suspecté de se livrer à un tel trafic en haute mer, mais, ce qui constitue le caractère propre d’une pareille capacité d’action est qu’elle doit s’inclure dans le respect des deux principes fondamentaux que sont, d’une part, la souveraineté des Etats, d’autre part, la liberté des mers définie par la Convention de Montego Bay de 1982, ceux-ci pouvant être antinomiques de celle-là. Avec la lutte contre le transport maritime de stupéfiants, la liberté des mers est devenue une liberté « encadrée ».Ceci pose de nombreuses difficultés d’interprétation et d’application des textes, qui ont conduit les Etats, par ailleurs souvent gênés dans leur action par la multiplication des structures intervenantes, à rechercher des solutions de coopération sur un plan opérationnel ou plus globalement avec des accords régionaux, pour résoudre de manière ponctuelle ou plus générale, certains types de problèmes.Dans ce contexte, les gouvernements ont en particulier perçu la nécessité de mettre en place des séries de mesures pratiques destinées à prévenir les menaces au niveau des différents maillons du réseau de transport maritime, singulièrement, et tout d’abord, en établissant un système d’information et de surveillance des approches maritimes, ensuite, en adoptant un ensemble de mesures de nature à organiser une meilleure sûreté portuaire avec le Code international pour la sûreté des navires et des ports (Code ISPS) et une meilleure sûreté concernant les conteneurs avec la Container security Initiative américaine.Là encore, l’instauration de cadres de coopération juridique et opérationnelle demeure, aujourd’hui comme pour le futur, une condition sine qua non du succès de la lutte contre un fléau mondial<br>In the 1970s, the drug trafficking underwent a fast growth and continually increased to globalize in the 1990s reaching a geopolitical dimension.Criminal organizations began to use large sea routes to transport the flow of drugs. These increased sea routes along with the measures related to the maritime sector contributed to the development of the world exchanges and the economic prosperity. Thus, this turned to be convenient to the development of drug trafficking.This important threat of sea transportation of narcotics made the States aware that it was necessary to repress this threat at international level.The previous international Agreements that were established by the United Nations are still valid. The latest Convention against the illicit traffic in Narcotics Drugs and Psychotropic substances, signed in Vienna in 1988 under article 17 determines how ships suspected of engaging in drug trafficking in open sea would be inspected.The Montego Bay Agreement of 1982 defined the freedom of seas along with the States desire to remain sovereign are two basic fundamental principles combined in this capacity. However with the fight against the drug trafficking over the seas, the freedom of seas became framed.The numerous difficulties of interpretation and application of texts led States, often hampered in their action by many structures, to look for solutions for cooperation on an operational plan or more globally with regional agreements, to meet short or long term solutions.In this context, the governments mainly perceived the necessity of setting up a series of practical measures intended to prevent the threats at the level of the various links of the maritime transport network, first of all, by establishing an information and monitoring system of the maritime approaches, then, by adopting a set of measures likely to organize better harbour safety with the International Ship and Port Security Code (code ISPS) and better safety concerning containers with American security Container Initiative.Once again, the institution of frames of legal and operational cooperation remains, today as for the future, an indispensable condition of the success of the fight against a world plague
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Vidakovic, Miodrag. "Optical fibre sensors applied to condition and structural monitoring for the marine and rail transport sectors." Thesis, City, University of London, 2017. http://openaccess.city.ac.uk/19664/.
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This thesis reports the development of a suite of FBG-based optical fibre sensors for non-destructive testing (NDT) and illustrating their potential for several specific industrial applications in the marine and railway sectors. These arose from work driven by the needs of project collaborators from these industries and are intended to be illustrative of the wider potential applications that optical fibre sensors have for measurements in different industrial sectors. The research has involved the development of new sensor system designs to meet these needs, building as they do upon a comprehensive review of NDT technologies and solutions, discussed in some detail. In this research for the marine sector, a single FBG-based acoustic sensor was specifically developed and evaluated and compared with the performance of conventional sensors. To do so, a metal plate to which the sensors were fixed was excited with a sonotrode, at a resonant frequency of 19.5 kHz. The signal reflecting that acoustic excitation was captured by the FBG sensors designed and implemented and their performance has been shown to be comparable with that from conventional, industry-standard piezoelectric transducers (PZTs). Preliminary work undertaken for the sponsors then lead to the further development of an acoustic sensor array comprising of 3 FBGs, which was subsequently validated against co-located PZTs which all were installed on a glass plate and excited in an industry-standard way, through the acoustic signal from a 0.2 g steel ball dropped onto the plate. When signals were analysed and compared, the positive comparative performance outcomes from the sensors used enabled further the design and implementation of instrumentation for a marine lifting surface using a different array, designed comprising 4 FBG-based acoustic sensors. Extensive tests on the smart marine lifting surface created were undertaken under water with a sonotrode set at 26 kHz as an excitation source. Based on the arrival time of acoustic signals captured by each grating and the use of triangulation method, the location of the excitation source could thus be determined, to meet the needs of the industrial sponsor and show good agreement with the outputs of conventional sensor systems. In parallel with the above, a further new industrial application of FBG-based sensor arrays was developed for a major player in the field, for the first time successfully instrumenting a railway current-collecting pantograph to allow reliable, remote in situ monitoring of key parameters: the contact force and contact location of the pantograph against the catenary. The optical fibre sensor approach has been shown to be an excellent means of measurement whose performance can be extrapolated to situations where the train is driven at high speeds up to 125 mph and powered from a high voltage line at 25 kV, in this design taking full advantages of the immunity of the optical fibre sensors to electromagnetic interference. In this research, key technical performance challenges were addressed and successfully overcome, including the temperature compensation needed for ‘all-weather’ performance, due to the intrinsic cross-sensitivity problems of using a FBG-based design being been fully addressed. This ensures the accurate measurement of the contact force/location between the pantograph and the catenary under all weathers. The research concludes by considering future directions for the work in these and other industry sectors.
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Jolivel, Maxime. "Érosion du pergélisol, transport fluvial et sédimentation marine, côte est de la baie d'Hudson, Nunavik, Canada." Doctoral thesis, Université Laval, 2014. http://hdl.handle.net/20.500.11794/25562.
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Cette thèse présente une étude du système érosion-transport-sédimentation en milieu de thermokarst dans un contexte de réchauffement climatique. La zone d’étude comprend le bassin versant de la rivière Sheldrake, 5 km au nord du village Umiujaq au Nunavik, ainsi qu’une zone de 15 km2 au large de son embouchure, dans le Passage de Nastapoka, en baie d’Hudson. Trois axes majeurs sont considérés: 1- l’étude des conditions de pergélisol et l’estimation quantitative des masses et volumes de sédiments et de carbone érodés à l’échelle du bassin versant ; 2- la mesure du régime hydrologique et sédimentaire du principal vecteur de transport, la rivière Sheldrake ; 3- la bathymétrie, la sédimentologie et la mesure des apports sédimentaires et organiques dans le milieu marin côtier au large de l’embouchure de la rivière. Dans le bassin versant de la rivière Sheldrake, le pergélisol s’est considérablement dégradé au cours des 50 dernières années, particulièrement dans la toundra forestière. La subsidence des lithalses, des palses, des plateaux de pergélisol et des plateaux palsiques engendre la formation de mares de thermokarst. De nombreux glissements de terrain et des ravins d’érosion sont également actifs et favorisent le rejet de sédiments dans le réseau fluvial. Avec la dégradation du pergélisol, la connectivité hydrologique augmente, ce qui facilite l’évacuation des sédiments et du carbone via le cours d’eau principal. Dans cet environnement thermokarstique, la charge sédimentaire fluviale en suspension est plus importante en été alors que les températures élevées de l’air commandent le dégel des sols, favorisant l’activation des ostioles et le déclenchement des glissements de terrain. Les pluies estivales permettent le transport et l’évacuation des sédiments en baie d’Hudson. Parvenus en mer, les sédiments et le carbone transportés en suspension subissent une forte dispersion à cause de l’intensité des courants marins du Passage de Nastapoka. Il en résulte l’absence d’une augmentation mesurable du taux de sédimentation. En revanche, la composition isotopique du carbone sédimentaire montre que la fraction terrigène a augmenté depuis le Petit Âge Glaciaire et que ce phénomène s’est considérablement accéléré vers la fin du 20ème siècle. Il est suggéré que la dégradation du pergélisol contribue à cette augmentation, quoique ce ne soit pas le seul facteur qu’on puisse invoquer.<br>This thesis studies the system erosion-transport-sedimentation in a thermokastic area, in a context of warming climate. The study area encompasses the catchment of the Sheldrake River, 5 km north of the village Umiujaq, Nunavik, and a 15 km2 area off its mouth, in the Nastapoka Sound, in Hudson Bay. Three main axes are considered: 1- study of permafrost conditions and quantitative estimate of the volumes and masses of eroded sediment and organic carbon at the scale of the catchment; 2- measurements of the hydrological and sedimentary regime of the main vector of transport, the Sheldrake River; 3- bathymetry, sedimentology and measurements of mineral and organic inputs in the coastal marine environment, off the river mouth. In the Sheldrake River catchment, permafrost has considerably degraded during the last 50 years, particularly in the forested tundra. Subsidence of lithalsas, palsas, permafrost plateaus and peat plateaus leads to the formation of thermokarst ponds. Many landslides and erosion gullies are also active and favor inputs of sediments in the fluvial network. Because of permafrost decay, hydrological connectivity increases, facilitating evacuation of sediment and carbon through the river. In this thermokarstic environment, the fluvial sedimentary load in suspension is more important during summer when high air temperatures provoke soils thawing, favoring frostboils activation and triggering of landslides. Summer rainfalls allow sediment transport and evacuation in Hudson Bay. Once in the sea, the sediments and carbon in suspension are dispersed because of the intensity of the marine currents in the Nastapoka Sounds. This results in an absence of a measurable increase of sedimentation rates. However, the isotopic composition of sedimentary carbon shows that the terrestrial fraction has increased since the Little Ice Age and that this trend has significantly accelerated since the end of the 20th century. It is suggested that permafrost decay contributes to this increase, although it is not the only proposed source.
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Garrison, Lance Preston. "The influence of physical transport and nutritional stress on the zoeae of estuarine crabs." W&M ScholarWorks, 1997. http://web.vims.edu/library/Theses/Garrison97.pdf.
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Littlejohn, Lexia M. "The impact of retreating sea ice on Arctic marine transport and development : an integrated risk and scenario-based approach to framing solutions for potential marine incidents /." May be available electronically:, 2008. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
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Chang, Lydia, and 張麗迪. "Transport of dinoflagellate cysts through ballast water and its implications for marine water monitoring in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B31252795.
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Chang, Lydia. "Transport of dinoflagellate cysts through ballast water and its implications for marine water monitoring in Hong Kong /." [Hong Kong : University of Hong Kong], 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13813481.
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Fuhrer, Mélanie. "TRANSPORT MARITIME DE PRODUITS CHIMIQUES LIQUIDES ET FLOTTANTS : ETUDE EXPERIMENTALE DU REJET ACCIDENTEL SOUS-MARIN SUITE A UN NAUFRAGE." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2012. http://tel.archives-ouvertes.fr/tel-00849580.
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Le transport par voie maritime s'est développé très rapidement durant la dernière décennie. Il constitue la solution idéale pour déplacer à faibles coûts d'importantes quantités de marchandises sur de longues distances. L'accroissement de ces échanges entraine inévitablement une augmentation de la fréquentation des routes maritimes, de la densité du trafic et donc du risque d'accident et de naufrage.Les quantités impliquées lors d'un accident étant importantes, un rejet sous-marin de produit chimique issu d'une épave peut provoquer de graves conséquences environnementales et humaines. Or, les mécanismes physico-chimiques apparaissant lors du transfert du produit à la surface sont encore mal compris. Ces mécanismes dépendent de nombreux paramètres dont les propriétés physico-chimiques intrinsèques au produit et celles propres à l'environnement de l'accident.Ce travail de recherche, réalisé en collaboration entre l'Ecole des Mines d'Alès et le Cedre, s'inscrit dans l'amélioration de la compréhension du comportement d'un rejet de produit chimique liquide, flottant et soluble issu d'une épave. Cette étude expérimentale a été réalisée selon 3 points :- La phénoménologie du rejet à la brèche dont l'objectif est de quantifier le débit et les modes de rejet,- Le comportement hydrodynamique du produit libéré et son évolution lors de la remontée dans la colonne d'eau,- Le transfert de matière du produit lors de sa solubilisation dans la colonne d'eau.Pour chaque point, les résultats obtenus sont comparés à ceux prédits par les corrélations disponibles dans la littérature afin de proposer une modélisation globale des conséquences adaptée à la gestion des pollutions marines.
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Puls, Amy L. "Transport of zooplankton in South Slough, Oregon." Thesis, Thesis (M.S.)--University of Oregon, 2002, 2002. http://hdl.handle.net/1794/10057.
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Balíková, Kateřina. "Kombinovaná nákladní přeprava nebezpečného zboží." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-125168.
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The Thesis gives the basic overview of requirements for dangerous cargo transport considering mode of transport (rail, road and marine). All conditions are desribed separately and then all together as intermodal transport. Part of the Thesis is dedicated to business practis in intermodal transport including INCOTERMS.
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Lo, Shek-yung Anthony, and 盧石勇. "The role of Hong Kong in the regional governance of water-borne transport service and infrastructure." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B29851579.
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Whittamore, Jonathan Mark. "The regulation of intestinal bicarbonate secretion by marine teleost fish." Thesis, University of Exeter, 2008. http://hdl.handle.net/10036/42297.
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In seawater, drinking is a fundamental part of the osmoregulatory strategy for teleost fish, and presents a unique challenge. The intestine has an established role in osmoregulation, and its ability to effectively absorb fluid from imbibed seawater is crucial to compensating for water losses to the surrounding hyperosmotic environment. Alongside solute-linked water transport (driven by NaCl cotransport), intestinal bicarbonate (HCO3-) secretion also benefits fluid absorption directly (via apical Cl-/HCO3- exchange), and indirectly through the formation of calcium carbonate (CaCO3) thus removing the osmotic influence of Ca2+ within the gut fluid. For the European flounder (Platichthys flesus), elevated luminal Ca2+ has proven to be a specific, potent stimulator of HCO3- secretion both in vitro and in vivo where these actions are presumably modulated by an extracellular Ca2+-sensing receptor (CaR). The focus of this work was to learn more about how intestinal HCO3- secretion is regulated, the role of Ca2+, and more specifically the CaR. To achieve this, in vitro ‘gut sac’ experiments investigated how luminal Ca2+ influenced HCO3- secretion, and associated ion and fluid transport. Contrary to expectation, increasing Ca2+ from 5 to 20 mM did not stimulate HCO3- secretion. In an attempt to elucidate the role of CaCO3 precipitation in fluid absorption, and further explore the physiological implications of HCO3- secretion, the intestine was perfused in vivo with salines containing varying concentrations of Ca2+ (10, 40 and 90 mM). The production and secretion of HCO3-, in addition to CaCO3 formation increased accordingly with Ca2+, and was associated with a dramatic 25 % rise in the fraction of fluid absorbed by the gut. Additional in vitro experiments, utilising the Ussing chamber, helped establish some of the characteristics of intestinal HCO3- secretion by the euryhaline killifish (Fundulus heteroclitus), but was unresponsive to elevated mucosal Ca2+. Further attempts to potentiate the activity of the CaR, and application of the receptor agonists gadolinium (Gd3+) and neomycin, failed to produce responses consistent with the effect of Ca2+ observed previously, either in vitro or in vivo. With no evidence supporting a direct role for an extracellular, intestinal CaR in HCO3- secretion it was argued that secretion would be principally regulated by two factors, the ability of the epithelia to generate high levels of intracellular HCO3- and the rate of CaCO3 formation.
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Le, Dantec Nicolas. "A study of saturated granular assemblages and its implications for transport, stress propagation and failure in marine sediments." Diss., [La Jolla] : University of California, San Diego, 2009. http://wwwlib.umi.com/cr/ucsd/fullcit?p3369001.
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Thesis (Ph. D.)--University of California, San Diego, 2009.<br>Title from first page of PDF file (viewed September 16, 2009). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
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Mandekar, Bedraya E. A. "Investigation of the role of microplastics in the transport of potentially toxic element species in the marine environment." Thesis, University of Strathclyde, 2018. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=30288.
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There is growing global concern about the impact of microplastics on the marine environment, with evidence emerging that plastic pellets can be a vector for potentially toxic elements (PTE). In this thesis, PTE content was first investigated in petroleum based (polyethylene, polypropylene and polyethylene terephthalate) and bio-based (poly(hydroxybutyrate-co-hydroxyvalerate)) virgin plastic pellets. Various elements associated with plastics' manufacture were detected. Next, sorption experiments were conducted to assess the capacity of virgin and laboratory-weathered pellets to take up As, Cd, Cr and Pb from controlled media of deionised, fresh and artificial seawater, with analysis by ICP-MS (Agilent 7700x instrument). All types of plastics showed the ability to take up the PTE studied and the total amounts were in the order Pb > As > Cd > Cr when single element solutions were studied and Pb > Cd > Cr > As from a multi-element solution. It was found that weathered pellets took up greater amounts of PTE than virgin ones. The surface of virgin, laboratory-weathered and beached pellets collected from Kuwait and Scotland were then imaged and their chemical composition determined using a scanning electron microscope with energy-dispersive EDS analyser (JEOL JSM-6010LA). Analysis revealed changes in pellet morphology following weathering. Elements detected were associated with aspects of plastic production or taken up from the ambient environment. Beached pellets were identified by ATR-FTIR as predominantly polyethylene and polypropylene. When examples were subjected to sequential cold acid digestion followed by microwave extraction, larger amount of PTE were released by the cold digestion step, indicating the analytes were relatively weakly bound. Samples from Kuwait released higher amounts of PTE than samples from Scotland. In vitro bioaccessibility of PTE to simulated fish stomach was estimated using two methods, a modified SBET and a 0.1 M HCl extraction. Lead was found to be the most bioaccessible of the PTE studied.