• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 70
  • 26
  • 17
  • 14
  • 12
  • 6
  • 5
  • 3
  • 3
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 207
  • 42
  • 41
  • 37
  • 25
  • 20
  • 18
  • 18
  • 18
  • 18
  • 18
  • 16
  • 15
  • 12
  • 11
  • 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.
151

西アフリカ稲作の拡大、集約化、持続性、コートジボワールとガーナの天水低湿地稲作の例

Sakurai, Takeshi, 櫻井, 武司 02 1900 (has links)
The proceedings included herein are the papers presented in the Seventh ICCAE Open Forum held in October 20th, 2006 at Nagoya University, Japan.
152

Upriver to Hue and Dong Ha: The U.S. Navy's War in I Corps, Vietnam 1967-1970

Chavanne, Jonathan Blackshear 2011 December 1900 (has links)
The United States Navy's involvement in the Vietnam War, especially its role in the region's inland waterways, has long been an overshadowed aspect of the conflict. Most histories ignore or minimize the Navy's contribution, especially its river patrol or 'brown water' role. Through archival and library research as well as interviews with U.S Navy Vietnam War veterans this thesis demonstrates the vital role played by the brown water navy in the northern provinces of South Vietnam. A key but understudied component of this effort was Task Force Clearwater, an improvised brown water fleet that-along with the maritime logistics campaign that it supported-would prove essential for the successful defense of South Vietnam's northernmost provinces and demonstrate the vital importance of inland naval power. Task Force Clearwater and its supported maritime logistics effort form a little explored component of the U.S. Navy's role in South Vietnam. A brown water task force that proved essential for the successful defense of the northern provinces of I Corps, Clearwater repeatedly demonstrated the vital importance of inland naval power and the critical need for reliable and protected routes of supply. The task force revealed many lessons that had been long understood, forgotten, and then relearned by the U.S. Navy, among them that control of inland waterways was perhaps the most advantageous form of logistical supply in war. Created in part to satisfy the ancient maxim of "keeping the supply lines open", the task force's role broadened with time. In the course of its existence the men and boats of Clearwater would provide not only the tools of war in I Corps but also provide key lessons for the future.
153

Análise de transporte multimodal na região da hidrovia Tietê-Paraná /

Bravin, Luís Fernando Nicolosi, 1969- January 2001 (has links)
Resumo: A hidrovia Tietê-Paraná foi aqui analisada sob o ponto de vista de seu aproveitamento para a navegação comercial, servindo para o escoamento dos produtos da rica região centro-oeste brasileira com destino ao porto de Santos (SP), com o objetivo de mostrar a vantagem competitiva de se utilizar a multimodalidade de transporte no escoamento de grãos. Considerando que o custo de transporte ou custo logístico chega, em alguns casos, a representar até 30% do valor final de vários produtos agrícolas, verificou-se que a navegação fluvial tornou-se um grande fator de redução no custo dos produtos, que necessitam de transporte em longa distância e, ao mesmo tempo, mantém um fluxo de carga muito elevado. Esta economia no custo de frete pode chegar a valores acima de 30%, quando se utiliza embarcações fluviais de terceiros e uma economia de mais de 40% ao se utilizar embarcações próprias, na fase do transporte hidroviário. Pela metodologia utilizada no trabalho foram identificadas duas regiões distintas: a consumidora e a produtora. Esta condição permitiu que fosse apresentado um estudo logístico específico, com maior detalhamento de rota e melhor especificação de equipamentos a serem utilizados, os quais permitiram obter resultados que possibilitaram otimizar o frete. Comparou-se os resultados desta análise de transporte com finalidade de obter relações entre custos e benefícios observados em outras modalidades de transporte utilizados nesta região, potencialmente rica e carente de transportes eficientes. / Abstract: The Tietê-Paraná's waterway was analyzed here under the point of view of its use for the commercial sailing; being good for the canal of the products of the rich center-west region of Brazil to Santos' harbour, with objective to show the advance multimodal transporting in grains drainage. Considering that the cost of transporting or logistic's cost reach thirty per cent of the final value of several agricultural products. The fluvial sailing is seen today as a great reduction factor in the costs of products, that need transport of long distance and at the same time it maintains a very high load flow. This reduction of freight may get thirty per cent if used undertaking boat, but forty per cent or more will be get if used self-boat. The work has a sequence that will begin with the general characterization of the area consumer, as well as the location of the producing areas, presenting a specific study where it will consist a larger route specially and the equipments to be it used. This source will show a series of calculations that they will have later as objective to arrive to a freight optimized in this project, which intends to offer the analysis of transport alternative comparable with the costs and benefits of the other modalities of this area, potentially rich and poor of efficient transports. / Orientador: Widsney Alves Ferreira / Coorientador: Marco Antônio Martin Biaggioni / Banca: Elias José Simon / Banca: Adilio F. de Lacerda Filho / Mestre
154

Projekt využití regionální vnitrozemské vodní dopravy pro cestovní ruch / The project for the use regional inland waterway transport for tourism

LAVIČKA, Pavel January 2013 (has links)
The main aim of this thesis was to analyze evaluate the possibility of using regional inland waterway transport for tourism. The thesis dealt with the newly navigable Vltava in South Bohemia, which was part of the state project "Completion of Vltava waterway in the section Ceske Budejovice - Tyn nad Vltavou". It was elaborate the situation analysis and realization of own exploration by means of structured interviews and survey. Based on the obtained data were created proposals to improve current situation. The main contribution of this thesis is the efficient interconnection of these suggestions would significantly increase the attractiveness of the whole idea navigable Vltava river for tourism. The most important output of the thesis is the elaboration of the project "Modernization of steamers on the Vltava river in South Bohemia".
155

Přepravy nebezpečných látek na území České republiky / Transport of Dangerous Substances in the Czech Republic

VANDAS, David January 2014 (has links)
The topic of the diploma written assignment is "Transport of Dangerous Substances in the Czech Republic" and it was chosen for elaboration of the wholesome view on the road, train, ship and plane transportation of the hazardous materials and mixtures. These transportations represent a possible risk of damage to life, health, property or environment for the society. Hazardous materials and mixtures nowadays are being transported in large measures and there is an assumption in the future that the volume of the transported hazardous materials and mixtures will increase. For elaboration of this written assignment three hypothesis were given: a) Legal regulations of the European Union and the Czech Republic solve the problematic of the transportation of hazardous materials and mixtures well enough. b) The public has enough information about the transportation of the hazardous chemical substances or mixtures. c) People that work in the field of the transportation of hazardous materials or mixtures are well informed about the transportation of hazardous chemical substances or mixtures. For determining whether the legal regulations solve the problematic of the transportation of hazardous materials and mixtures well enough the literary sources which deal with this issue, legal regulations of the Czech Republic and the European Union and other international agreements were used. After working through these sources it was found out that the international, the EU and Czech legal regulations or agreements solve this issue well enough and emphasis is given on convergence of legal regulations of all transportations. Implementation of international agreements and legal regulations of the European Union into the legal regulations of the Czech Republic happens in the present time very fast and without failures. For figuring out the awareness of the public and awareness of the people working in the field of the transportation of hazardous materials and mixtures for the diploma written assignment on the topic of "The Transportation of Hazardous Materials and Mixtures on the Territory of the Czech Republic" there was a quantitative research made. The quantitative research was made with the help of handed out questionnaires. The public was represented by the employees of the Regional Municipalities of the Czech Republic. Both of the groups were given the same questionnaires. The results of the questionnaire research were evaluated, expressed in percentage and statistically assessed. For the statistical assessment the double selection T-test was used to find out whether the difference between the assessed groups is statistically important. People working in the transportation of hazardous substances and mixtures have sufficient information which was confirmed by the questionnaire research. By the made statistical assessment it was found out that the difference between the groups is statistically significant and so the public does not have sufficient information related to the transportation of hazardous substances and mixtures. Due to the results of the questionnaire research and mainly that the hypothesis b) - The public has enough information about the transportation of hazardous chemical substances or mixtures was not confirmed. In the conclusion of the written assignment there are a couple of suggestions for improvement of the awareness of the public. For example as a part of education at primary and high schools and training schools where this education is already running as a part of The Protection of Human during Incidents. This education has been going on since 2003. And that is why the older people in the public are not well met with this issue and they should be introduced to it by for example a media campaign by means of short TV spots on public television channels or by means of spots that already the Independent BESIP Department of the Ministry of Transportation makes up. These spots are called Besipky.
156

Parameterization of bio-optical models for estimating chlorophyll-a concentration in a tropical eutrophic reservoir / Parametrização de modelos bio-ópticos para estimação da concentração de clorofila-a em um reservatório eutrófico tropical

Watanabe, Fernanda Sayuri Yoshino [UNESP] 15 March 2016 (has links)
Submitted by Fernanda Sayuri Yoshino Watanabe null (fernandasyw@yahoo.com.br) on 2016-04-28T12:54:41Z No. of bitstreams: 1 Watanabe_tese.pdf: 3879331 bytes, checksum: f393ffe1bbc36d214f1bed6945d9dedd (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-02T12:36:43Z (GMT) No. of bitstreams: 1 watanabe_fsy_dr_prud.pdf: 3879331 bytes, checksum: f393ffe1bbc36d214f1bed6945d9dedd (MD5) / Made available in DSpace on 2016-05-02T12:36:43Z (GMT). No. of bitstreams: 1 watanabe_fsy_dr_prud.pdf: 3879331 bytes, checksum: f393ffe1bbc36d214f1bed6945d9dedd (MD5) Previous issue date: 2016-03-15 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The aim of this research was to parameterize and calibrate models based on remote sensing data in order to estimate accurately the chlorophyll-a concentration, [Chl-a], in a tropical eutrophic reservoir. Firstly, a bio-optical characterization was conducted to identify particularities in the study area. Thus, existing empirical models and quasi-analytical algorithms (QAA) were tested and, after, parameterized and calibrated for the investigated environment. Such models derive [Chl-a] and inherent optical properties (IOPs), respectively, from remote sensing reflectance (Rrs). This research was developed in the Barra Bonita hydroelectric reservoir (BBHR), lies in Tietê River (Brazil). Reservoirs are artificial environments which change severely the hydrodynamic of rivers and the biogeochemical balance of aquatic systems. Such alterations can lead to unique bio-optical status and, consequently, models developed for rivers and lakes are not suitable to explain the processes which happen in reservoirs. The trophic state is an important water quality parameter and can be determined based on Chl-a concentration, photosynthetically active pigment present in all the phytoplankton species and detected by remote sensors. Therefore, the use of orbital and aerial images is a viable alternative to monitoring of trophic state in these environments. Results showed that bio-optical status in BBHR is remarkable different compared to other aquatic systems found in literature, corroborated by inaccurate performance of models proposed to other areas. The parameterization and calibration proposed in this research estimated accurately Chl-a concentration, mainly, adopting absorption coefficients derived by QAA. The fitted models can be used in mapping trophic state and frequent monitoring of water quality in BBHR by environmental agency and hydroelectric plant managers. In addition, it is likely that the parameters proposed in this research are suitable for other inland waters. / O objetivo do presente trabalho foi parametrizar e calibrar modelos baseado em dados de sensoriamento remoto para estimar acuradamente a concentração da clorofila-a, [Chl-a], em um reservatório tropical e eutrofizado. Primeiramente, uma caracterização bio-óptica da área estudo foi realizada para identificar particularidades do ambiente. Então, modelos empíricos e algoritmos quase-analíticos (QAA) existentes foram testados e, posteriormente parametrizados e calibrados para o ambiente investigado. Tais modelos derivam a [Chl-a] e propriedades ópticas inerentes (POIs), respectivamente, a partir da reflectância de sensoriamento remoto (Rrs). Esta pesquisa foi desenvolvida no reservatório da hidroelétrica de Barra Bonita (RHBB), localizado no Rio Tietê (Brasil). Reservatórios são ambientes artificiais que modificam severamente a hidrodinâmica de rios e o equilíbrio biogeoquímico do ecossistema aquático. Tais alterações podem proporcionar características bio-ópticas únicas ao ambiente e modelos para rios e lagos podem não ser adequados para explicar os processos que ocorrem em reservatórios. O grau de eutrofização é um importante parâmetro de qualidade da água e pode ser determinado com base na [Chl-a], pigmento fotossiteticamente ativo presente em todas as espécies de fitoplâncton, detectado por sensores remotos. Portanto, o uso de imagens orbitais e aerotransportadas é uma alternativa viável para o monitoramento do estado trófico desses ambientes. Resultados mostram que as características bio-ópticas em RHBB são consideravelmente diferentes de outros ambientes pesquisados na literatura, corroborado com desempenho não acurado de modelos propostos para outros ambientes. A parametrização e calibração propostas nesta pesquisa estimaram acuradamente a [Chl-a], principalmente, adotando os coeficientes de absorção derivados do QAA. Os modelos ajustados podem ser utilizados no mapeamento do estado trófico e monitoramento periódico da qualidade da água em RHBB por agências ambientes e gestores de usinas hidroelétricas. Além disso, é provável que os parâmetros propostos nesta pesquisa sejam adequados para outras águas continentais. / CNPq: 200157/2015-9
157

From oligo to eutrophic inland waters: advancements and challenges for bio-optical modeling

Rodrigues, Thanan Walesza Pequeno [UNESP] 09 March 2017 (has links)
Submitted by THANAN WALESZA PEQUENO RODRIGUES null (twalesza@gmail.com) on 2017-04-18T13:46:33Z No. of bitstreams: 1 Tese_Final2017.pdf: 5871584 bytes, checksum: 622c90a26db9966bfc3a2c9aaf97e829 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-04-18T19:10:58Z (GMT) No. of bitstreams: 1 rodrigues_twp_dr_prud.pdf: 5871584 bytes, checksum: 622c90a26db9966bfc3a2c9aaf97e829 (MD5) / Made available in DSpace on 2017-04-18T19:10:58Z (GMT). No. of bitstreams: 1 rodrigues_twp_dr_prud.pdf: 5871584 bytes, checksum: 622c90a26db9966bfc3a2c9aaf97e829 (MD5) Previous issue date: 2017-03-09 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho teve como objetivo realizar um levantamento detalhado das características bio-ópticas nos reservatórios de Barra Bonita (BB) e Nova Avanhandava (Nav) com o intuito de avaliar o desempenho de uma única abordagem voltada para a estimativa das propriedades ópticas inerentes (POIs), assim como, a concentração de totais sólidos suspensos (TSS). A investigação foi realizada utilizando dados coletados no campo entre 2014 e 2016, incluindo, as POIs, componentes opticamente significativos (COSs) e reflectância de sensoriamento remoto (R_rs). Os dados apresentados dos COSs confirmaram que BB é um ambiente mais túrbido que Nav por apresentar maior produção fitoplanctônica em função do recebimento de altas cargas de nutrientes provenientes da bacia de drenagem. Por outro lado, Nav é um ambiente mais transparente e com maior influência de material inorgânico, o que favorece o surgimento de macrófitas submersas. A concentração de clorofila-a (Chl-a) em BB alcançou máximo de 797.8 µg l-1 em outubro/2014, enquanto Nav apresentou máximo de 38.6 µg l-1 em maio/2016. A variabilidade nos COS esteve altamente vinculada a frequência de chuvas, sendo que no ano de 2014, ocorreu um evento extremo de seca alterando as características biogeoquímicas dos ambientes. BB reagiu de forma mais abrupta que Nav por apresentar um sistema de operação do tipo acumulação e por estar mais próxima das regiões potencialmente poluidoras, diferente de Nav que apresenta um sistema fio-d’água em que não há acumulação e sim fluxo constante da água. Além disso, no âmbito óptico, a absorção em Nav apresentou maior influência do particulado não-algal (NAP) enquanto que em BB, a absorção foi dominada por fitoplâncton. Com base nesses resultados pode-se concluir que os dois ambientes apresentam não só diferenças na qualidade da água, mas também nas propriedades ópticas, o que leva a afirmação de que um modelo único baseado nos dois ambientes pode não ter um bom resultado quando se pretende utilizar uma abordagem empírica. Um algoritmo quase-analítico (QAA) parametrizado para as condições de Nav (QAAOMR) apresentou resultados significativos com erros (erro médio percentual absoluto – MAPE) inferiores a 17% para o coeficiente de absorção total (a_t), 19% para o coeficiente de absorção orgânico detrital (a_CDM) e 47% para o coeficiente de absorção do fitoplâncton (a_ϕ). O respectivo modelo foi utilizado para verificar seu desempenho em um ambiente eutrofizado como BB e a versão parametrizada por Watanabe et al. (2016) e denominada QAABBHR foi aplicada aos dados de Nav. Como resultado, observamos que as duas versões foram adequadas para estimar a_t com erros inferiores a 40%, no entanto, existe ainda a necessidade de melhorar as etapas para estimativa de a_CDM e a_ϕ. No caso de se aplicar um modelo empírico de única abordagem para estimar concentração de TSS para ambos os reservatórios, observamos que essa abordagem não apresentou resultados satisfatórios, portanto, modelos específicos baseados na banda do vermelho do MODIS foram utilizados para mapear TSS em cada um dos reservatórios. Pode-se concluir então, que o conhecimento acerca das propriedades ópticas da água se mostrou determinante para a modelagem bio-óptica, principalmente no que diz respeito aos ambientes altamente contrastantes como BB e Nav. / The objective of the present work was to perform a detailed survey of the bio-optical characteristics of the reservoirs of Barra Bonita (BB) and Nova Avanhandava (Nav) in order to evaluate the performance of a single approach aimed at estimating the inherent optical properties (IOPs), as well as the concentration of total suspended solids (TSS). The research was carried out using data collected in the field between 2014 and 2016, including the IOPs, optically significant components (OSCs) and remote sensing reflectance (R_rs). The data presented from the OSCs confirmed that BB is more turbid than Nav because it presents higher phytoplankton production due to the input of high nutrient loads from the drainage basin. On the other hand, Nav is more transparent with greater influence of inorganic matter, which favors the appearance of submerged macrophytes. The concentration of chlorophyll-a (Chl-a) in BB reached a maximum of 797.8 μg l-1 in October/2014, while Nav presented a maximum of 38.6 μg l-1 in May/2016. The variability in the COS was highly related to the frequency of rainfall, in the year 2014, an extreme drought event occurred, altering the biogeochemical characteristics. BB reacted more abruptly than Nav because it presented an accumulation type operation system and because it is closer to the potentially polluting region. Nav presents a water system in which there is no accumulation but constant flow of water. In addition, in the optical context, the absorption in Nav presented greater influence of the non-algal particulate (NAP) while in BB, the absorption was dominated by phytoplankton. Based on these results, it can be concluded that the two environments present not only differences in water quality but also in optical properties, which leads to the assertion that a single model based on the two environments may not have a good result when it is intended to use empirical approach. A quasi-analytical algorithm (QAA) parameterized for Nav conditions (QAAOMR) presented significant results with errors (mean absolute percentage error - MAPE) lower than 17% for the total absorption coefficient (a_t), 19% for the carbon detrital matter absorption coefficient (a_CDM) and 47% for the absorption coefficient of phytoplankton (a_ϕ). The respective model was used to verify its performance in a eutrophic environment such as BB and the version parameterized by Watanabe et al. (2016) and named QAABBHR was applied to the Nav data. Thus, we note that the two versions were suitable for estimating a_t with errors (MAPE) less than 40%, however, improvements must be carried out for estimating a_CDM and a_ϕ. In the case of applying a single empirical model to estimate TSS concentration for both reservoirs, we observed that it did not present satisfactory results, so specific models based on the MODIS red band were used to map TSS in each of the reservoirs. It can be concluded, therefore, that knowledge about the optical properties of water has proved to be determinant for the bio-optical modeling, especially with respect to highly contrasting environments such as BB and Nav. / CNPq: 200152/2015-7
158

Remote sensing of chlorophyll-a concentration based on absorption coefficients in Ibitinga reservoir / Sensoriamento Remoto da concentração de clorofila-a baseado nos coeficientes de absorção no reservatório de Ibitinga

Andrade, Caroline Piffer de 23 March 2018 (has links)
Submitted by Caroline Piffer de Andrade (carol_piffer@hotmail.com) on 2018-04-28T18:02:37Z No. of bitstreams: 1 CarolinePifferdeAndrade.pdf: 3287357 bytes, checksum: beca78c3926ad0af4d896e61b2ecaf99 (MD5) / Approved for entry into archive by ALESSANDRA KUBA OSHIRO ASSUNÇÃO (alessandra@fct.unesp.br) on 2018-05-02T13:23:34Z (GMT) No. of bitstreams: 1 andrade_cp_me_prud.pdf: 3003528 bytes, checksum: 19259069721e1c717d15aa96a145d1fb (MD5) / Made available in DSpace on 2018-05-02T13:23:35Z (GMT). No. of bitstreams: 1 andrade_cp_me_prud.pdf: 3003528 bytes, checksum: 19259069721e1c717d15aa96a145d1fb (MD5) Previous issue date: 2018-03-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente estudo objetivou estimar as concentrações de clorofila-a (Chl-a) no reservatório da usina hidroelétrica de Ibitinga (RHI), localizado no Rio Tietê, estado de São Paulo, Brasil, por meio de coeficientes de absorção obtidos via algoritmos quase-analíticos (QAAs). Para isso, realizou-se uma caracterização bio-ótica e biogeoquímica do RHI, por meio de dados espectrais e de qualidade da água coletados em dois trabalhos de campo, conduzidos em Julho de 2016 e Junho de 2017. Os desempenhos das versões originais QAAV5 e QAAV6 em estimar as propriedades óticas inerentes (POIs) no RHI foram avaliados. Versões re-parametrizadas para dois reservatórios localizados no sistema em cascata do Rio Tietê, QAABBHR e QAAOMW, foram também testadas para a área de estudo. Além disso, foram avaliadas as performances de esquemas compostos pelas versões do QAA já mencionadas, seguidas por quatro modelos para estimativa de Chl-a, os quais utilizam coeficientes de absorção como dados de entrada. A distribuição espacial das concentrações de Chl-a foi analisada por meio da aplicação desses esquemas em uma imagem do sensor Ocean and Land Colour Instrument (OLCI) instalado a bordo do satélite Sentinel-3A, com aquisição coincidente com o segundo trabalho de campo realizado na área de estudo. A caracterização bio-ótica demonstrou variabilidade espacial e temporal dos constituintes oticamente significativos (COSs) no RHI, com predominância da absorção pelo material orgânico colorido dissolvido (CDOM). As versões do QAA testadas para o primeiro conjunto de dados não se mostraram completamente adequadas na obtenção de coeficientes de absorção em todos os comprimentos de onda. Com relação aos esquemas para estimativa de concentração de Chl-a, apenas aqueles baseados no QAAV5 foram capazes de obter resultados razoáveis - Raiz do Erro Médio Quadrático Normalizado (REMQN) < 47.50 % - para os dados da imagem OLCI. Todos os quatro modelos para estimativa de Chl-a testados apresentaram resultados similares para os dados de saída do QAAV5. Esses resultados enfatizam o desafio gerado pela grande variabilidade ótica dos sistemas em cascata, com relação à modelagem bio-óptica. Os resultados obtidos dão suporte a futuros trabalhos, os quais podem resultar em aplicações como o monitoramento do estado trófico na área de estudo a partir de dados de satélite, com maior acurácia proveniente do uso de modelos que possam estimar consistentemente suas POIs. / This research was aimed at retrieving chlorophyll-a (Chl-a) concentrations in Ibitinga Hydroelectric Reservoir (IHR), located at Tietê River, São Paulo State, Brazil, using absorption coefficients obtained via Quasi-analytical algorithms (QAAs). For this purpose, a bio-optical and bio-geochemical characterization of IHR was carried out, through spectral and water quality data collected in two field campaigns conducted in July, 2016 and June, 2017. The suitability of two QAA native forms (QAAV5 and QAAV6) in retrieving inherent optical properties (IOPs) in IHR was assessed. Versions re-parameterized for two reservoirs also located in the Tietê River cascading system, QAABBHR and QAAOMW, were also tested for the study area. Besides that, the performances of schemes composed by the QAA versions already mentioned followed by four models that use absorption coefficients as inputs for estimating Chl-a concentration in Ibitinga Reservoir were evaluated. Spatial distribution of Chl-a in the reservoir was analyzed, since these schemes were applied in an image of the Ocean and Land Colour Instrument (OLCI) sensor onboard Sentinel-3A satellite, with acquisition date coincident with the second field campaign. The bio-optical characterization showed spatial and temporal variability of optically significant constituent (OSC) in IHR and colored dissolved organic matter (CDOM) predominance in its absorption budget. None of the QAA versions tested for the first dataset was completely satisfactory in retrieving absorption coefficients for IHR in all wavelengths. Regarding the schemes for Chl-a concentration estimates, only the ones based on QAAV5 were able to obtain reasonable results - Normalized Root Mean Square Error (nRMSE) < 47.50 % - for the OLCI image data. All four models for Chl-a estimation tested presented similar results for QAAV5 outputs. These results highlight the challenge of copying with high optical variability in cascading systems. The results obtained support further works, which can, prospectively, lead to many practical applications, as monitoring of trophic state in the study area from satellite data, with higher accuracy provided by the use of models that can consistently retrieve the IOPs for this specific water system. / FAPESP: 2012/19821-1 e 2015/21586-9
159

Conceito de embarcações adaptadas à via aplicado à navegação fluvial no Brasil. / Waterway adapted ships concept applied on Brazilian inland navigation.

Carlos Daher Padovezi 03 October 2003 (has links)
É elaborada uma proposta de procedimentos de projetos de comboios fluviais adaptados às condições existentes das vias navegáveis, a partir de uma visão ampliada da necessidade de obtenção de menores custos de transporte, com níveis adequados de segurança e de respeito ao meio ambiente. Uma análise das inter-relações técnicas entre hidrovias e embarcações, assim como dos condicionantes e implicações do conceito de embarcações adaptadas às vias navegáveis, orientou a elaboração do modelo. Este foi estruturado em módulos, com o objetivo de reproduzir, um a um, os fatores mais importantes que influenciam a eficiência, a segurança e o nível de interferência ambiental do transporte de cargas por comboios. Um programa computacional foi desenvolvido como instrumento de aplicação do modelo, consolidando os procedimentos propostos para a escolha das melhores alternativas de projeto e de operação de comboios. Resultados experimentais com comboios em escala real e com modelos em tanques de provas, foram utilizados para validação dos procedimentos adotados. Dados de acidentes com comboios em várias hidrovias do mundo foram utilizados como bases para avaliações de risco. O modelo foi aplicado aos casos de transportes de soja pela hidrovia Tietê-Paraná e pelo rio Araguaia, exemplificando as formas de análise e de escolha das alternativas de soluções de projeto. Ao final, os resultados obtidos comprovaram a utilidade da adoção de um enfoque mais abrangente do processo de projeto de comboios fluviais. / It is proposed a procedure model for design of barges push-tow adapted to waterway actual conditions, with the purpose of minimize transportation costs but always making verifications of navigation safety and ambient interferences levels. An analysis of inter-relations on inland waterways and cargo ships and, also, detailed conditionings and implications of waterway adapted ships concept, was used for model elaboration. It was structured in blocks to reproduce, one to one, the most important factors that modify efficiency, safety and environmental interference levels of barges push-tow cargo transportation. A computational program was developed to consolidate the proposed model and to apply procedures to choose best design and operational alternatives. Results of full scale and towing tank tests with push-tows were used to verify the mathematical and semi-empirical models. Barges push-tows accidents data from waterways of the world was used as risk model basis. To evaluate its effectiveness, the model was applied to bulk grain transportation cases by Tietê-Paraná waterway and by Araguaia river. The results shows that the special emphasis on three factors (efficiency, safety and ambient) improves the quality of barges push-tow design process.
160

Vnitrozemská vodní doprava v ČR / Inland waterway transport in the Czech Republic

Honzáková, Tereza January 2013 (has links)
Thesis deals with the efficiency of inland waterways in the Czech Republic and its measure which would lead to its greater use. For this precaution is considered a project the Weir in Děčín and without this, the project can not proceed in the construction of other projects in the Czech inland waterways. The first part is devoted to the description of inland waterways as part of the trans-European networks. Furthermore there are institutions in charge of the developement and operation of waterways. Legislation defining the rules to ensure continuity of water transport is also important in the developement and operation. The second part deals with positive relationship between freight water transport and economy of the Czech Republic. I describe in the last chapter of the thesis project the Weir in Děčín and the subsequent project of navigability of the Elbe River to Pardubice and construction of the Danube-Oder-Elbe.

Page generated in 0.0597 seconds