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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.
1

Allocation of rights over offshore oil and gas resources : a study of the legal systems in force in the United States, the United Kingdom, Canada and Australia

Crommelin, Michael January 1972 (has links)
This thesis is concerned with one aspect of government management regimes for offshore oil and gas - the allocation of rights over these resources. The method by which rights may be acquired, the scope of the rights, and the terms and conditions upon which they are obtained are matters of great significance in determining the overall effectiveness of a management regime. Four coastal nations have been chosen for study. They are the United States of America, the United Kingdom of Great Britain and Northern Ireland, Canada and Australia. The systems adopted by these countries for allocation of offshore oil and gas rights are similar in that they rely mainly upon private enterprise for the development of the resources, but otherwise there are considerable differences. In the first place, the thesis contains a brief statement of the nature and extent of the rights of coastal nations over offshore oil and gas resources at international law. This is to provide the basic framework within which the management regimes of the four countries must operate. Secondly, there is a detailed description of the allocation systems in each of the four countries, with special attention being given to the historical background of the laws which establish the systems, to the provisions of those laws, and to the practical operation of the systems. Finally, there is a comparative assessment of the systems in terms of specific objectives which should form the basis of a government management regime for offshore oil and gas. / Law, Peter A. Allard School of / Graduate
2

Characteristics of the High Speed Gas-Liquid Interface

Weiland, Christopher Jude 19 February 2010 (has links)
The objective of this dissertation was to investigate physical characteristics of high speed gas-liquid interfaces for the cases of subsonic, transonic, and supersonic gas jets submerged underwater and the transient development of an underwater projectile reaching the supercavitating state. These studies are motivated by the need to understand the basic physics associated with a novel submersible missile launcher termed the Water Piercing Missile Launcher (WPML). This dissertation presents the first study of high speed round and rectangular gas jets submerged underwater utilizing a global optical measurement technique. This technique allows quantitative measurement of the entire gas jet and the interfacial motion. Experimental results indicate that the penetration of the gas jets into a quiescent liquid is strongly influenced by the injection mass flow and the nozzle geometry. In contrast, the oscillations of the interface are influenced by the injection Mach number. The transition from a momentum driven to a buoyant jet is determined using a characteristic length scale that appears to be in good agreement with experimental observations. Moreover, the unsteadiness of the interface appears to be governed by both Kevin-Helmholtz and Rayleigh-Taylor instabilities. This dissertation also contains the first study of a projectile accelerating to reach the supercavitating state. Experimental results show that the transient development of the supercavity is governed by the formation of a vortex ring. Nuclei are shed from the forebody of the accelerating projectile and are entrained in the vortex ring core where they are subjected to low pressure and subsequently expand rapidly. A characteristic time scale for this supercavity development is presented. / Ph. D.
3

A cross-cultural analysis of the policy, application and effect of legislation concerning archaeological sites in reservoirs, and implications for future reservoir works and site monitoring

Stammitti, Emily Jean January 2015 (has links)
The number of dams and reservoirs in the world is at an all-time high, with global increases expected as water shortages, populations and needs for electricity grow. Despite this high number of existent and planned reservoirs, the archaeological sites submerged in reservoirs have been largely ignored saving predevelopment, project-specific archaeological salvage campaigns. The overlooking of submerged archaeological features derives from ideas that sites in reservoirs are destroyed: a notion that continues to permeate discussions surrounding archaeological features in reservoir flood zones. Heritage legislation, at both the domestic and international level, continues to neglect the pressing issue of monitoring the condition of submerged archaeology. This dissertation analyses the domestic heritage legislation of three specific countries (Britain, the USA and Egypt) and heritage legislation at the international level. Effects of submergence on diverse archaeological features from those countries are also taken into account via the data collected from varying types of archaeological investigation: the desk-based assessment, underwater archaeological fieldwork, and non-intrusive terrestrial fieldwork. Analysis of current legal structures suggests that mechanisms with which to monitor sites and provide mitigating measures would be simple to implement and maintain. Data collected through underwater archaeological fieldwork in Britain and terrestrial archaeological fieldwork in the USA suggests that not all types of archaeological sites are at risk of destruction due to submergence, leading to a classification of vulnerable features, determined on the basis of location in the reservoir and construction materials and methods. Mitigating and monitoring measures of these vulnerable feature classifications can be used in future reservoir planning and archaeological conservation efforts, when combined with changes to regional and domestic heritage policy. Final conclusions focus on the need to classify archaeology in reservoirs as "submerged landscapes", an already recognized underwater archaeological category, thereby helping to grant the long-needed protection, awareness and monitoring these features need throughout their duration in situ.
4

Modelagem espaço-temporal da colonização de macrófitas submersas no reservatório de Taquaruçu

Batista, Lígia Flávia Antunes [UNESP] 25 November 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-11-25Bitstream added on 2014-06-13T20:21:14Z : No. of bitstreams: 1 batista_lfa_dr_prud.pdf: 2832429 bytes, checksum: 6a04247002ae8968fcab468a8a207011 (MD5) / Este trabalho propõe um modelo espaço-temporal para o desenvolvimento de macrófitas submersas no reservatório de Taquaruçu, rio Paranapenama, no município de Santo Inácio, estado do Paraná. A abordagem de construção do modelo é teórico-empírica, baseada em dados. O estudo da vegetação submersa é relevante pois a sua proliferação excessiva acarreta desequilíbrio ecológico e prejuízos econômicos para usinas hidrelétricas. Foram realizados dez levantamentos de campo no reservatório de Taquaruçu, rio Paranapenama. Utilizou-se a técnica hidroacústica para mapear a vegetação e a profundidade e foram adquiridas medidas limnológicas. A análise exploratória mostrou grande redução da infestação de 2009 para 2010, justificada pela intensa precipitação ocorrida no período. Constatou-se regiões de crescimento e decaimento da vegetação, heterogeneamente distribuídas no espaço e no tempo. O modelo gerado divide-se em: modelo pontual, determinístico, que descreve o crescimento vertical da vegetação, independente da vizinhança e modelo probabilístico, para estimar a propagação da vegetação em área. O modelo pontual foi baseado no modelo logístico, caracterizado pela curva sigmoidal. As variáveis utilizadas foram profundidade e coeficiente de atenuação. Os coeficientes do modelo foram calibrados com algoritmos genéticos, com a utilização de 18 pontos, coletados entre abril e agosto de 2010. Os dados de entrada deste modelo foram gerados com interpolação por krigeagem ordinária e resolução de 3 m. Na etapa de validação utilizou-se de 12 pontos, em que avaliou-se a estatística descritiva dos resíduos, índices de qualidade de ajustamento, análise gráfica da... / The focus of this work is to design a spatiotemporal model of submerged macrophyte development. The model developing approach is empirical, based on field data. The study of submerged vegetation is important due to its excessive proliferation, which causes ecological unbalance and economical losses to hydroelectric power plants. Ten field surveys were made in Taquaruçu reservoir, Paranapanema river. Hydroacoustic techniques were used to map the vegetation and depth, and limnological measurements were made. Exploratory analysis showed a great infestation reduction from 2009 to 2010, probably caused by the precipitation volume which occurred in that time. Macrophyte growth and decay regions were distributed in space and time in a heterogeneous way. The model produced is divided in: local model, deterministic, which describes the vertical vegetation growth, without neighborhood influence; and the probabilistic model, which estimates the macrophyte propagation in area. The local model was based on the logistic model whose curve is sigmoidal. The variables used were depth and attenuation coefficient. Model coefficients were calibrated with genetic algorithms, with 18 points collected between April and August 2010. Input data were generated with ordinary kriging interpolation and a resolution of 3 m. In the validation phase 12 points were used and descriptive statistics of residual... (Complete abstract click electronic access below)
5

A Numerical Analysis of Fully Nonlinerar Waves Passing Submerged and Floating Breakwaters

Chen, Pei-Hong 14 February 2001 (has links)
­^¤åºK­n A time-independent finite-difference numerical scheme is developed to study the dynamic response of a submerged and a floating breakwater under the wave loading of a fully numerical force. The coupled surge, heave and pitch motion of a floating breakwater and the wave-structure interaction are included in the model. The numerical results are validated uses several bench mark studies and results available elsemlse. The wave reducing effect of a submerged and a floating breakwaters were analysis and discusse.
6

The British North Sea : the importance of and factors affecting tax revenue from oil production /

Hill, Mark Thomas, January 2003 (has links) (PDF)
Thesis (M.A.)--Brigham Young University. David M. Kennedy Center, 2003. / Includes bibliographical references (p. 82-85).
7

The acoustic ecology of submerged macrophytes

Wilson, Christopher James, 1985- 25 January 2012 (has links)
Underwater acoustics has recently emerged as a viable tool for assessing ecosystem health and exploring the estuarine soundscape. Recent acoustic surveys have mapped distributions of both seagrass meadows and kelp forests, and scientists are currently developing remote sensing capabilities to improve ecological assessments of these communities. Furthermore, researchers are beginning to focus on the propagation and ecological significance of bioacoustic signals within estuarine landscapes. The research presented here includes a thorough examination of the interaction of acoustic energy and macrophyte tissue as it pertains to habitat assessment and ecosystem function. Modeling experiments investigated the interaction of acoustic energy and submerged macrophyte tissue. Both seagrasses and kelp exhibited a similar acoustic response by increasing the acoustic compressibility of a seawater medium. The increase in acoustic compressibility was driven by free-gas volumes contained within the macrophyte tissue. Interestingly, the tissue served to limit the acoustic compressibility of the gas volume below the magnitude predicted by effective medium models. Separate inquiries of high-frequency sound propagation and the seagrass canopy revealed a significant temporal component to acoustic transmission. Specifically, sound transmission throughout a seagrass canopy was altered by the formation of free gas bubbles and the pressurization of aerenchyma channels, which was mediated by photosynthesis. The photosynthetic controls on sound propagation were species-specific, and patterns of acoustic transmission provided a reasonable proxy for gross primary production in Syringodium filiforme plants. Finally, the interaction of sound energy and submerged macrophytes appears to have important ecological implications. This research suggests that seagrass meadows scatter high-frequency sound energy and provide an acoustic refuge to fish from marine mammal predators. This refuge is highly seasonal, specific to different seagrass species and dependent on the abundance of above-ground biomass. Seagrasses also may influence the transmission of low-frequency sounds used by soniferous fish. Propagation characteristics of low-frequency sounds are highly dependent on frequency and result in differential transmission distances among individual fish species. It is clear from this body of work that submerged macrophytes are an important feature of the underwater soundscape. Future research should continue to exploit this feature for remote sensing purposes and examine its ecological significance. / text
8

SEABED MINERAL RESOURCES--AN ANALYSIS OF CONFLICTING NATIONAL POLICIES IN THE UNITED NATIONS SEABED COMMITTEE

Vosburgh, John A., 1933- January 1976 (has links)
No description available.
9

Influência dos macronutrientes no crescimento de Myceliophthora thermophila I-1D3b em cultivo submerso / Influence of macronutrients on the growth of Myceliophthora thermophila I-1D3b in submerged culture

Silva, Gisele Fernanda Alves da 01 December 2017 (has links)
Submitted by GISELE FERNANDA ALVES DA SILVA null (giferalves@hotmail.com) on 2018-01-10T17:26:28Z No. of bitstreams: 1 MESTRADO DISSERTACAO Gisele Fernanda Alves da Silva.pdf: 2130722 bytes, checksum: 912b62510cfa3114cbd4a44325ccec9d (MD5) / Approved for entry into archive by Elza Mitiko Sato null (elzasato@ibilce.unesp.br) on 2018-01-11T17:30:59Z (GMT) No. of bitstreams: 1 silva_gfa_me_sjrp.pdf: 2130722 bytes, checksum: 912b62510cfa3114cbd4a44325ccec9d (MD5) / Made available in DSpace on 2018-01-11T17:30:59Z (GMT). No. of bitstreams: 1 silva_gfa_me_sjrp.pdf: 2130722 bytes, checksum: 912b62510cfa3114cbd4a44325ccec9d (MD5) Previous issue date: 2017-12-01 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fungos filamentosos secretam grande quantidade de proteínas e outros produtos metabólicos para o meio de crescimento. As substâncias secretadas dependem não só das características metabólicas do microrganismo, como também da composição nutricional do meio de cultivo, particularmente dos macroelementos. Sendo assim, o objetivo do presente trabalho foi avaliar a influência dos macronutrientes, carbono e nitrogênio, no crescimento e secreção de amilases, CMCase e xilanase do fungo Myceliophthora thermophila I-1D3b, em cultivo submerso. Atuando como fonte de carbono, foram escolhidos amido solúvel, carboximetilcelulose, papel de filtro e glicose e como fonte de nitrogênio sulfato de amônio, peptona e extrato de levedura. O crescimento fúngico foi determinado pela quantificação de biomassa micelial. Foram realizados ensaios de cinética de crescimento microbiano e de secreção das enzimas mencionadas, alternando-se e associando-se as fontes de carbono e nitrogênio, procurando estabelecer uma correlação entre a disponibilidade de fontes simples e complexas de carbono e de fonte orgânicas e inorgânicas de nitrogênio, na síntese de biomassa e secreção de enzimas amilase, CMCase e xinalase. Realizou-se ensaios variando a fonte de nitrogênio, peptona, sulfato de amônia e extrato de levedura em concentração fixa de glicose. Determinou-se a concentração de nitrogênio presente nos substratos utilizados como fonte de nitrogênio e calculou-se a massa de substrato necessário para oferecer as respectivas concentrações de nitrogênio, 10 e 13%. Também foram realizados experimentos variando as fontes de carbono em amido solúvel, Carboximetilcelulose e papel de filtro, em diferentes concentrações (2,5; 5,0; 7,5 e 10,0 g.L-1). Esse mesmo experimento foi realizado variando as fontes de carbono combinados à glicose. Foram obtidos como resultados maiores valores de biomassa em presença de fonte orgânica de nitrogênio, enquanto maiores atividades enzimáticas foram obtidas em cultivo constituído de fontes orgânicas e inorgânicas na proporção 2:1, respectivamente. Quando avaliada a influência das fontes de nitrogênio, peptona e extrato de levedura, ambas avaliadas em função da concentração de 10% e 13% de nitrogênio, não foram observadas diferenças significativas na composição de biomassa micelial ao fim de 120h de cultivo. Identificou-se influência da concentração de nitrogênio na atividade de CMCase, sendo que as melhores atividades obtidas ocorreram para a concentração de 13% de peptona e extrato de levedura. No entanto, não foi possível identificar a influência da concentração de nitrogênio na atividade de xilanase e amilase. No estudo das fontes de carbono, mostrou-se como melhor fonte de carbono na obtenção de biomassa fúngica o amido solúvel. Maiores atividades enzimáticas foram obtidas em presença de seus indutores: CMCase foram obtidas em cultivo constituído de carboximetilcelulose, e amilase em cultivo com amido solúvel. Quando as fontes de carbono foram combinadas à glicose, observou-se redução nas atividades das enzimas analisadas. Nesse trabalho, observou-se que cada fonte de carbono proporcionaram efeitos diferentes sobre crescimento microbiano e atividades enzimáticas, dada as características distintas de sua composição química e estrutural. / Filamentous fungi secrete large amounts of proteins and other metabolic products into the growth medium. The secret substances depend not only on the metabolic characteristics of the microorganism but also on the nutritional composition of the culture medium, particularly the macroelements. Therefore, the objective of the present work was to evaluate the influence of macronutrients, carbon and nitrogen on the growth and secretion of amylases, CMCase and xylanase of fungus Myceliophthora thermophila I-1D3b, in submerged culture. Acting as a carbon source, soluble starch, carboxymethylcellulose, filter paper and glucose and as source of nitrogen ammonium sulfate, peptone and yeast extract were chosen. Fungal growth was determined by the quantification of mycelial biomass. Microbial growth and secretion kinetics assays were performed alternating and associating as carbon and nitrogen sources, trying to establish a correlation between the availability of simple and complex sources of carbon and of organic and inorganic sources of nitrogen, in the synthesis of biomass and secretion of amylase enzymes, CMCase and xinalase. Tests were performed by varying the source of nitrogen, peptone, ammonium sulfate and yeast extract at fixed glucose concentration. The concentration of nitrogen present in the substrates used as nitrogen source was determined and the substrate mass required to provide as 10 and 13% nitrogen solutions was calculated. Experiments were also carried out, varying as carbon sources in soluble starch, Carboxymethylcellulose and filter paper, in different concentrations (2.5, 5.0, 7.5 and 10.0 gL-1). sources of carbon combined with glucose. As results obtained higher biomass values in the presence of organic nitrogen source, while higher enzymatic activities were obtained in organic and inorganic sources in the 2: 1 ratio, respectively. When evaluated by an influence of nitrogen sources, peptone and yeast extract, both evaluated as a function of 10% and 13% nitrogen concentration, were not significantly observed in the composition of mycelial biomass after 120 h of culture. The influence of nitrogen concentration on CMCase activity was identified, with the best activities obtained for a concentration of 13% of peptone and yeast extract. However, it was not possible to identify an influence of the nitrogen concentration on xylanase and amylase activity. In the study of carbon sources, the soluble starch was shown to be the best source of carbon in the production of fungal biomass. Higher enzymatic activities were obtained in the presence of its inducers, CMCase were obtained in culture consisting of carboxymethylcellulose and amylase in culture with soluble starch. As carbon sources were combined with glucose, it observed a reduction in the activities of the enzymes analyzed. In this work it was observed that each carbon source had different effects for microbial growth and enzymatic activities, given as distinct characteristics of its chemical and structural composition.
10

Modelagem espaço-temporal da colonização de macrófitas submersas no reservatório de Taquaruçu /

Batista, Lígia Flávia Antunes. January 2011 (has links)
Orientador: Nilton Nobuhiro Imai / Coorientador: Edivaldo Domingues Velini / Banca: Tiago Garcia de Senna Carneiro / Banca: Thiago Sanna Freire Silva / Banca: Robinson Antonio Pitelli / Banca: Messias Meneguette Júnior / Resumo: Este trabalho propõe um modelo espaço-temporal para o desenvolvimento de macrófitas submersas no reservatório de Taquaruçu, rio Paranapenama, no município de Santo Inácio, estado do Paraná. A abordagem de construção do modelo é teórico-empírica, baseada em dados. O estudo da vegetação submersa é relevante pois a sua proliferação excessiva acarreta desequilíbrio ecológico e prejuízos econômicos para usinas hidrelétricas. Foram realizados dez levantamentos de campo no reservatório de Taquaruçu, rio Paranapenama. Utilizou-se a técnica hidroacústica para mapear a vegetação e a profundidade e foram adquiridas medidas limnológicas. A análise exploratória mostrou grande redução da infestação de 2009 para 2010, justificada pela intensa precipitação ocorrida no período. Constatou-se regiões de crescimento e decaimento da vegetação, heterogeneamente distribuídas no espaço e no tempo. O modelo gerado divide-se em: modelo pontual, determinístico, que descreve o crescimento vertical da vegetação, independente da vizinhança e modelo probabilístico, para estimar a propagação da vegetação em área. O modelo pontual foi baseado no modelo logístico, caracterizado pela curva sigmoidal. As variáveis utilizadas foram profundidade e coeficiente de atenuação. Os coeficientes do modelo foram calibrados com algoritmos genéticos, com a utilização de 18 pontos, coletados entre abril e agosto de 2010. Os dados de entrada deste modelo foram gerados com interpolação por krigeagem ordinária e resolução de 3 m. Na etapa de validação utilizou-se de 12 pontos, em que avaliou-se a estatística descritiva dos resíduos, índices de qualidade de ajustamento, análise gráfica da... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The focus of this work is to design a spatiotemporal model of submerged macrophyte development. The model developing approach is empirical, based on field data. The study of submerged vegetation is important due to its excessive proliferation, which causes ecological unbalance and economical losses to hydroelectric power plants. Ten field surveys were made in Taquaruçu reservoir, Paranapanema river. Hydroacoustic techniques were used to map the vegetation and depth, and limnological measurements were made. Exploratory analysis showed a great infestation reduction from 2009 to 2010, probably caused by the precipitation volume which occurred in that time. Macrophyte growth and decay regions were distributed in space and time in a heterogeneous way. The model produced is divided in: local model, deterministic, which describes the vertical vegetation growth, without neighborhood influence; and the probabilistic model, which estimates the macrophyte propagation in area. The local model was based on the logistic model whose curve is sigmoidal. The variables used were depth and attenuation coefficient. Model coefficients were calibrated with genetic algorithms, with 18 points collected between April and August 2010. Input data were generated with ordinary kriging interpolation and a resolution of 3 m. In the validation phase 12 points were used and descriptive statistics of residual... (Complete abstract click electronic access below) / Doutor

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