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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Distribution of Organotin Compounds in the Fishing Ports of Pingtung County

Lu, Yu-ting 07 September 2012 (has links)
Samples including surface sediments and seawaters were collected from eighteen ports of Pingtung County. The objective of this study were to understand sources of organotin pollution and to monitor the organotin pollution of these fishing ports by analying with gas chromatography-flame photometric detection (GC-FPD). ¡@The results showed that butyltins were the major components of organotin pollution of the fishing ports investigated. The concentrations of MBT, DBT, TBT and MPT in seawaters varied between 3.9~51.6 ng/L as tin, ND~15.2 ng/L as tin, ND~23.9 ng/L as tin and 2.1~7.2 ng/L as tin. The concentrations of MBT, DBT, TBT and MPT in surface sediments varied between 67~332 ng/g as tin, 17.6~325 ng/g as tin, 26~420 ng/g as tin and ND~43.7 ng/g as tin. ¡@The contents of organotin compounds were relevant to the number of fishing craft and the frequency of fishery activities. Distribution of organotin compounds between seawaters and surface sediments in these fishing ports were correlational. Phenyltin was detected only in a few ports, probably due to the sewage discharge from the nearby villages. The concentrations of organotin compounds observed in this study are lower than most of the reported values from foreign ports. In comparison with the previous studies in the same areas, organotin concentrations have dropped significantly. These observations are attributed to the effective control over the utilization of organotin compounds by the authorities.
62

Factors of East Asian maritime security

Butler, Bryce D. January 2003 (has links) (PDF)
Thesis (M.A.)--Naval Postgraduate School, 2003. / Title from title screen (viewed Apr. 5, 2004). "ADA414654"--URL. Includes bibliographical references (p. 87-91). Also issued in paper format.
63

Improving wave forecasting in variable wind conditions : the effect of resolution and growth rate for the catalan coast

Alomar Domínguez, Marta 03 December 2012 (has links)
The main objective of this study is to improve wind wave forecasting in the NW Mediterranean Sea while focusing on the characteristic sharp gradients of the wind and wave conditions. This work was motivated by the limited accuracy of wave models in semi-enclosed-basins and orography-controlled wind conditions, especially during fetch-limited storm events. First, to reduce the commonly observed under-estimation of wave parameters, the mesoscale variability of wind and wave fields was characterized in time (1 h to 1 day) and in space (10 km to 100 km). Second, to better capture the typical sharp gradients, the grid size of the input wind fields was decreased during a characteristic storm event from 18 km to 4 km and the wind input frequency was increased from 6 h to 1 h. Third and last, the rate of wave growth in the numerical model was tuned in order to match the local rate of wave growth. The rate of non-dimensional growth in the region of study, which was calculated using measurements along the fetch, turned out to be faster than simulated using the default physical parameterizations and faster than reported in previous studies. Adjusting the wave growth rate in the model to the observations improved the estimated wave height about 18 % and the peak frequency about 4%. Decreasing the grid size of the numerical models from 12 km to 4 km improved the timing of the wave peaks but not the maximum values of the storm. Increasing the frequency of the wind input (from 6 h to 3 h) improved the estimation of the maximum wave height values (peaks) of the storm about 13%. Summarizing, the results of this work indicated that tackling wind and wave gradients in complex regions such as the study area it is posible to reduce the under-estimation of wave parameters and to improve wave forecasting. / L’objectiu principal d’aquest estudi és millorar les prediccions de l’onatge generat pel vent al Mediterrani Noroccidental enfocant-se en els forts gradients de vent i d’onatge característics de la zona. Aquest treball sorgeix de la falta d’exactitud dels models d’onatges en conques semi tancades i en condicions de vent controlades per l’orografia, especialment durant temporals d’onatge limitats pel ‘fetch’. En primer lloc, per tal reduir les sub-estimacions dels parametres de l’onatge, s’ha caracteritzat la variabilitat dels camps de vent i d’onatge tant en temps (entre 1 h i un 1 dia) com en espai (entre 10 i 100 km). En segon lloc, per tal de capturar els forts gradients típics de la zona en els models numèrics d’onatge, durant un temporal característic s’ha reduit el tamany de malla dels vents d’entrada al model de 18 km a 4 km i s’ha augmentat la freqüència d’entrada dels vents de 6 h a 1 h. En tercer i últim lloc, s’ha ajustat la tasa de creixement de l’onatge en els models numèrics d’acord amb la tasa de creixement obtinguda a partir d’observacions locals. La tasa de creixement a la zona d’estudi, que s’ha calculat utilitzant mesures al llag del fetch, ha resultat ser més rápida que la predita utilitzant les parametritzacions incorporades per defecte en els models, i més rápida que les tases obtingudes en experiments anteriors. El fet d’ajustar la tasa de creixement en el model d’onatge ha permès millorar un 18% l’alçada d’ona significant estimada i un 4 % la freqüència de pic de l’onatge. Reduir el tamany de malla dels vents d’entrada de 12 km a 4 km ha permès millorar l’estimació en el temps dels pics d’onatge, però no els valors màxims del temporal. En canvi, augmentar la freqüència dels vents d’entrada (de 6 h a 3 h) ha millorat un 13% l’estimació dels valors màxims d’alçada d’ona durant el temporal. En resum, els resultats d’aquest treball indiquen que abordant els gradients de vent i onatge en regions complexes és posible reduir la sub-estimació dels paràmetres de l’onatge i millorar-ne la seva predicció. / El objetivo principal de este estudio es mejorar las predicciones del oleaje generado por el viento en el Mediterráneo Noroccidental enfocando los fuertes gradientes de viento y oleaje característicos de la zona. Este trabajo surge de la falta de exactitud de los modelos de oleaje en cuencas semi-cerradas y en condiciones de viento controladas por la orografía, especialmente durante temporales de oleaje limitados por el ‘fetch’. En primer lugar, para reducir las sub-estimaciones de los parámetros del oleaje, se caracterizó la variabilidad de los campos de viento y oleaje tanto en tiempo (entre 1 h y un 1 día) como en espacio (entre 10 y 100 km). En segundo lugar, para capturar los fuertes gradientes típicos de la zona en los modelos numéricos de oleaje, para un temporal característico, se redujo el tamaño de malla de los vientos de entrada al modelo de 18 km a 4 km y se aumentó la frecuencia de entrada de los vientos de 6 h a 1 h. En tercer y último lugar, se ajustó la tasa de crecimiento del oleaje en los modelos numéricos de acuerdo a la tasa de crecimiento obtenida a partir de observaciones locales. La tasa de crecimiento en la zona de estudio, que se calculó usando medidas de viento y oleaje a lo largo del fetch, resultó ser más rápida que la predicha utilizando las parametrizaciones incorporadas por defecto en los modelos, i más rápida que les tases obtenidas en experimentos anteriores. El hecho de ajustar la tasa de crecimiento en el modelo de oleaje permitió mejorar un 18% la altura de ola significante estimada y un 4 % la frecuencia de pico del oleaje. Reducir el tamaño de malla de los vientos de entrada de 12 km a 4 km permitió mejorar la estimación en el tiempo de los picos de oleaje, pero no los valores máximos del temporal. En cambio, aumentar la frecuencia de los vientos de entrada (de 6 h a 3 h) ha mejorado un 13% la estimación de los valores máximos de altura de ola durante el temporal. En resumen, los resultados de este trabajo indican que abordando los gradientes de viento y oleaje en regiones complejas se reduce la subestimación de los parámetros del oleaje y se mejora su predicción.
64

Stitching identities : work, play and politics among Sri Lanka's free trade zone garment factory workers

Hewamanne, Sandya 25 April 2011 (has links)
Not available / text
65

IT Strategy at the National Ports Authority of South Africa.

Govender, Alan. January 2003 (has links)
This study on IT strategy was conducted at the National Ports Authority of South Africa. Firstly literature review was undertaken in the field of Business Strategy and to a larger extent on IT strategy. This culminated in a model that could be used to benchmark against the IT strategy being used at the National Ports Authority of South Africa. Due consideration was also given to the implementation of strategy in the literature review which could be compared with the implementation of strategy at the National Ports Authority of South Africa. The company situation was thereafter presented and discussed in context with what was covered in the literature review. An impact study of the IT strategy on the business processes at the National Ports Authority was also conducted. Interviews were conducted to determine what was working well and also what was not working well at the National Ports Authority of South Africa. Finally recommendations were provided to the National Ports Authority of South Africa on how to improve the business processes and the strategy formulation process. / Thesis (MBA)-University of Natal, Durban, 2003.
66

Strategies for improving import yard performance at container marine terminals

Martín Alcalde, Enrique 22 July 2014 (has links)
The process of containerization and its continuous development involves changes and technological innovations in containerships and maritime container terminals. In the current era of "gigantism", despite existing fleet overcapacity, shipping companies are booking larger and fuel-efficient vessels to benefit from economies of scale and to reduce operating costs. Consequently, port terminals have to cope with unprecedented container volumes and increasing demands, as a result, handling operations are likely to be subject to delay. In this context, container terminals are dealing with the huge challenge of readjusting themselves in order to, on one hand, improve productivity and level of service offered to the customers (minimize turnaround time) and, on the other hand, to manage terminal handling operations efficiently with the aim of reducing operating costs and becoming more competitive. Moreover, considering that adapting facilities and terminal infrastructures involves large investment and given the lack of space in many urban ports for expanding the operational area, the improvement of handling operations efficiency is more important than ever. Thus, many efforts are required to improve the productivity of container terminals by introducing efficient solutions and optimization techniques to decision-making processes and, on the other side, introducing technological improvements such as the automation of handling equipment. In light of this, this thesis is focused on the optimization of handling operations in the storage yard, which is considered to be the most complex terminal subsystem since terminal performance depends on its efficiency. In particular, it attempts to: (1) determine optimal storage space utilization by considering the yard inventory and congestion effects on terminal performance; (2) introduce new allocating storage strategies with the aim of minimizing the amount of rehandling moves, which are considered to be the most important cause of inefficiency in container yard terminals, and; (3) develop a generic storage pricing schedule to encourage customers to pick up their containers promptly and, as a consequence, reduce the average duration of stay, avoiding yard congestion. In order to tackle these issues, two different analytical models are introduced in this thesis. The first one aims to forecast storage yard inventory by dealing explicitly with stochastic behavior, yard inventory peaks and seasonal fluctuations. The second one, which is based on probabilistic and statistical functions, is derived to estimate the average number of rehandles when containers with different departure probabilities are mixed in the same stack. Finally, the numerical experiments presented in this thesis prove the usefulness of the different analytical models, yard design methods, cost models and operative and tactical strategies developed herein. These can be applied by other researchers, planners and terminal operators to optimize the yard handling processes, to improve their efficiency rates and to increase terminal throughput without incurring large investment. By being technically efficient, the terminal will be more cost-efficient as well, resulting in the overall optimization of terminal performance.
67

Control through design

Dorow, Rory T. J. January 2009 (has links)
Thesis (M.Arch.)--University of Detroit Mercy, 2009. / Includes bibliographical references.
68

Évaluation du potentiel des capteurs acoustiques sous-marins dans l'inspection des infrastructures portuaires /

Brahim, Naouraz. January 2009 (has links) (PDF)
Thèse (M.Sc.)--Université Laval, 2009. / Bibliogr.: f. [103]-106. Publié aussi en version électronique dans la Collection Mémoires et thèses électroniques.
69

The Manaus free trade zone and deforestation in the state of Amazonas

Rivas, Alexandre A. F. January 1998 (has links)
Thesis (Ph. D.)--University of Tennessee, 1998. / Vita. Includes bibliographical references (leaves 103-108).
70

The role of the U.S. Navy in support of the national strategy for maritime security

Winter, Peter J. January 2006 (has links)
Thesis (M. of Strategic Studies)--U.S. Army War College, 2006. / Cover title. "15 MAR 2006"--Tech. report doc. page. Includes bibliographical references (p. 15-17). Full text document available on public STINET.

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