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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

Minimum paths to interception of a moving target when constrained by turning radius

Looker, Jason R. January 2008 (has links) (PDF)
Mode of access: Internet via World Wide Web. Available at http://hdl.handle.net/1947/9741. / "December 2008" "AR No. AR 014-359" "DSTO-TR-2227" Includes bibliographical references.
2

Charting the Northwest Coast 1857-62: a case study in the use of "Knowledge as Power" in Britain’s Imperial ascendency

Wallace, Richard William 05 1900 (has links)
This thesis will deal with the hydrographic survey of the BC coast and the international boundary settlement conducted by HM ships Plumper, Satellite, and Hecate from 1857 to 1863. It will examine the geo-political importance of the pursuit of "knowledge as power" in light of American expansionism and the utilisation of the surveyors as a significant force of law and order; their importance to the social and commercial development of BC; and their contribution to the safety of navigation and the exploration of the BC coast.
3

A process based method to estimate the hydrograph from small agricultural watersheds

Stone, Jeffry Joel, January 1990 (has links) (PDF)
Thesis (Ph.D. - Renewable Natural Resources)--University of Arizona. / Includes bibliographical references (leaves 190-192).
4

Charting the Northwest Coast 1857-62: a case study in the use of "Knowledge as Power" in Britain’s Imperial ascendency

Wallace, Richard William 05 1900 (has links)
This thesis will deal with the hydrographic survey of the BC coast and the international boundary settlement conducted by HM ships Plumper, Satellite, and Hecate from 1857 to 1863. It will examine the geo-political importance of the pursuit of "knowledge as power" in light of American expansionism and the utilisation of the surveyors as a significant force of law and order; their importance to the social and commercial development of BC; and their contribution to the safety of navigation and the exploration of the BC coast. / Arts, Faculty of / History, Department of / Graduate
5

A hydrographic investigation of a mixed-energy inlet : Rich Inlet, North Carolina /

Knierim, Adam Clair. January 2004 (has links)
Thesis (M.S.)--University of North Carolina at Wilmington, 2004. / Includes bibliographical references (leaves : [48]-52).
6

A process based method to estimate the hydrograph from small agricultural watersheds

Stone, Jeffry Joel,1948- January 1990 (has links)
The kinematic wave model for overland and channel flow is used to develop a method to calculate the runoff hydrograph from a watershed consisting of a cascade of planes and channels. First, a general, semi-analytic solution based on the method of characteristics and incorporating flow on infiltrating surfaces is derived. Unrealistic properties of previous solutions based on the method of characteristics are avoided by defining lateral inflow in relation to the presence or absence of flowing water on the flow surface. It is shown that the new definition of lateral inflow results in both a more physically realistic representation of the overland and channel flow process during the recession stage of the hydrograph and a more accurate estimation of runoff volume than obtained by previous solutions. Second, the concept of the storage of water at kinematic equilibrium is used to calculate a depth-discharge coefficient for a single plane system and a two plane, one channel system, each of which is hydraulically equivalent to a complex cascade of planes and channels. The method is validated on two rangeland watersheds in Arizona. The results show that hydrographs generated from the two simplified watershed geometries are essentially the same as those from complex geometries when the duration of the runoff event is equal to or greater than the time to kinematic equilibrium. At durations less than the time to kinematic equilibrium, the two plane, one channel system preserves the complex geometry properties better than the single plane system.
7

Long-term changes in the hydrography of the European shelf seas since 1905, and the effects of these upon the distribution and abundance of various marine organisms

Dickson, R. R. January 1967 (has links)
No description available.
8

Análise integrada da paisagem na bacia hidrográfica do rio Caeté - Amazônia Oriental - Brasil

Gorayeb, Adryane [UNESP] 10 November 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-11-10Bitstream added on 2014-06-13T18:40:36Z : No. of bitstreams: 1 gorayeb_a_dr_rcla.pdf: 3603159 bytes, checksum: 98bc31f9585b44e693d3b2126e3bd0a6 (MD5) / A bacia hidrográfica do rio Caeté está inserida no nordeste do Pará e possui 2.195 km2 e extensão do rio principal de 149 km. O intuito principal foi o de elaborar um estudo da paisagem da bacia do Caeté e avaliar o nível de degradação ambiental. Os procedimentos foram divididos em quatro etapas: 1) levantamento bibliográfico e cartográfico, 2) trabalhos de campo, 3) análises laboratoriais da água superficial e subterrânea e 4) trabalhos de gabinete. Realizou-se: i) levantamento socioeconômico; ii) caracterização das unidades geoambientais; iii) elaboração do diagnóstico da qualidade da água; iv) avaliação das condições do lixão e v) identificação dos fatores de degradação. Foram identificadas quatro unidades: Planalto Costeiro, Planície Costeira, Planície Fluvial e Planície Estuarina. O saneamento básico é inexistente e as principais atividades estão relacionadas com a agropecuária, extrativismo vegetal e pesca artesanal e semi-industrial. Como principais problemas foram identificados o desmatamento, a prática da mineração, a potencial poluição hídrica no rio e seus afluentes e a forte tendência à contaminação pela disposição incorreta dos resíduos sólidos. Além de causar problemas ao meio, esses fatores também acarretam prejuízos diretos para as comunidades, haja vista o consumo de água de baixa qualidade e a disseminação de doenças. / The Caeté river hydrographic basin is located in the northeastern of Pará and has 2.195 km2 and extent of the main river of 149 km. The main goal of this research was preparing an integrated study of the environment context of Caeté’s river and to assess the level of environmental degradation. The analysis was based on landscape study and the procedures were divided into four stages: 1) analyses bibliographic and mapping, 2) work of field, 3) analysis of water quality and 4) work office. There were analyses related to the definition and characterization of the environmental units, socioeconomic survey, diagnosis of water quality, environmental assessment of the public dumps and identification of the factors of environmental degradation. The survey found that the environmental units inserted in the basin are the Coastal Plateau and Coastal Plain. The main economic activities are related to agriculture and extraction of plant and fishing. As main environmental problems had been identified the deforestation, the practice of mining, the potential water pollution and the strong trend to water contamination by the incorrect disposal of solid waste.
9

Análise integrada da paisagem na bacia hidrográfica do rio Caeté - Amazônia Oriental - Brasil /

Gorayeb, Adryane. January 2008 (has links)
Resumo: A bacia hidrográfica do rio Caeté está inserida no nordeste do Pará e possui 2.195 km2 e extensão do rio principal de 149 km. O intuito principal foi o de elaborar um estudo da paisagem da bacia do Caeté e avaliar o nível de degradação ambiental. Os procedimentos foram divididos em quatro etapas: 1) levantamento bibliográfico e cartográfico, 2) trabalhos de campo, 3) análises laboratoriais da água superficial e subterrânea e 4) trabalhos de gabinete. Realizou-se: i) levantamento socioeconômico; ii) caracterização das unidades geoambientais; iii) elaboração do diagnóstico da qualidade da água; iv) avaliação das condições do lixão e v) identificação dos fatores de degradação. Foram identificadas quatro unidades: Planalto Costeiro, Planície Costeira, Planície Fluvial e Planície Estuarina. O saneamento básico é inexistente e as principais atividades estão relacionadas com a agropecuária, extrativismo vegetal e pesca artesanal e semi-industrial. Como principais problemas foram identificados o desmatamento, a prática da mineração, a potencial poluição hídrica no rio e seus afluentes e a forte tendência à contaminação pela disposição incorreta dos resíduos sólidos. Além de causar problemas ao meio, esses fatores também acarretam prejuízos diretos para as comunidades, haja vista o consumo de água de baixa qualidade e a disseminação de doenças. / Abstract: The Caeté river hydrographic basin is located in the northeastern of Pará and has 2.195 km2 and extent of the main river of 149 km. The main goal of this research was preparing an integrated study of the environment context of Caeté's river and to assess the level of environmental degradation. The analysis was based on landscape study and the procedures were divided into four stages: 1) analyses bibliographic and mapping, 2) work of field, 3) analysis of water quality and 4) work office. There were analyses related to the definition and characterization of the environmental units, socioeconomic survey, diagnosis of water quality, environmental assessment of the public dumps and identification of the factors of environmental degradation. The survey found that the environmental units inserted in the basin are the Coastal Plateau and Coastal Plain. The main economic activities are related to agriculture and extraction of plant and fishing. As main environmental problems had been identified the deforestation, the practice of mining, the potential water pollution and the strong trend to water contamination by the incorrect disposal of solid waste. / Orientador: Magda Adelaide Lombardo / Coorientador: Luci Cajueiro Carneiro Pereira / Banca: Marcello Martinelli / Banca: Valdir Schalch / Banca: Antônio Carlos Tavares / Banca: Sérgio dos Anjos Ferreira Pinto / Doutor
10

The seasonal dynamics of chaetognath assemblages in relation to hydrographic factors in the waters surrounding Taiwan

Mei, Pu-kai 05 February 2010 (has links)
This study aims to study the species composition and distribution of chaetognaths in the waters surrounding Taiwan January 2005 to July 2006, and to explore the relationship between environmental factors and their dynamic distribution. Waters surrounding Taiwan are affected by monsoons and water masses. In winter, the northwestern Taiwan area is under the impact of low-temperature low-salinity China Coastal Current, but in summer, Taiwan Strait is affected by South China Sea Current going northward with high-temperature and high-salinity. As for eastern waters of Taiwan, Kuroshio current passes throughout the year so it is high-temperature and high-salinity. In July 2006, when three typhoons struck Taiwan, excessive fresh water from land flowed into the ocean and stations along the coast where low in salinity. This study identified a total of 28 species of chaetognath under 14 genera of 4 families, with average abundance at 475 ¡Ó 35 ind./100m3, which shows an obvious change related to seasons, relatively low in winter and spring and high in summer and fall. The seven most dominant species are: Flaccisagitta enflata, Serratosagitta pacifica, Zonosagitta littoralis, Pterosagitta draco, Aidanosagitta regularis, Aidanosagitta bedfordii and Aidanosagitta neglecta, accounting for 85% of the total abundance. The distribution of chaetognath in waters surrounding Taiwan is affected by the different water masses. The northwestern area where China Coastal Current passes through has high abundance but less number and low Shannon diversity index, but the eastern and southern waters dominated by Kuroshio current shows a completely different trend. From the results of multiple regression analysis, it is found that the abundance of chaetognath and F. enflata are in positive correlation with that of the abundance of copepod, indicating that the quantity of food might be a factor affecting the distribution of chaetognath. The second dominant species S. pacifica has no relation with hydrographic or biological factors, and the third dominant species Z. littoralis is in negative correlation with temperature and salinity. Along with the results of indicator species analysis, Z. littoralis can possibly be used as indicators species of China Coastal Current. The three predominant species are dominated by the Stage I and significantly less in other growth stages. The average body lengths (ABL) of F. enflata and S. pacifica are the larger in spring and smaller in fall, with obvious changes with seasons, but that of Z. littoralis is larger in winter and summer and smaller in spring and fall. Different water masses have impacts on distribution of weight mean stage (WMS) and ABL of chaetognath; for example, F. enflata and S. pacifica with the equivalent growth have larger bodies in Kuroshio current than in China Coastal Current, but Z. littoralis which prefers cold water shows an opposite trend. In addition, this study found that abundance, species, Shannon diversity index, WMS and ABL of chaetognath has no differences between day and night, but the succession of water masses in waters surrounding Taiwan may be an important factor affecting the distribution patterns of chaetognaths.

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