Made available in DSpace on 2014-10-09T12:38:08Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:39Z (GMT). No. of bitstreams: 1 05649.pdf: 6795207 bytes, checksum: c03839663e599700ba2154bbedff9b1c (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

No description available.

A aceitação de rejeitos radioativos em um repositório final depende, entre outras coisas, do conhecimento do inventário radioisotópico presente neles. Para obter essa informação, é necessário fazer a caracterização primária dos rejeitos de modo que a composição seja conhecida e oriente os passos seguintes da gestão. Os filtros cartucho que são utilizados no sistema de retratamento de água do reator de pesquisa IEA-R1 é um desses rejeitos. O IEA-R1 é um reator de pesquisa do tipo piscina, operando entre 2 e 5 MW, que utiliza a água como líquido de arrefecimento, moderador e blindagem biológica Além do seu uso em pesquisa, também é utilizado para produzir radioisótopos e irradiar amostras. Ele está localizado no Instituto de Pesquisas Energéticas e Nuclear, no campus da Universidade de São Paulo. Os filtros cartucho são utilizados para reter o material particulado em suspensão presente na água. Quando os filtros ficam saturados e são incapazes de manter o fluxo dentro dos limites estabelecidos, eles são substituídos e descartados como rejeito radioativo. Após um período de espera para o decaimento da atividade, são enviados para Gerência de Rejeitos Radioativos (GRR). O objetivo deste trabalho é apresentar os estudos realizados para determinar a atividade dos emissores gama presentes nos filtros cartucho. As atividades foram calculadas utilizando as taxas de dose medidas com detectores portáteis, as relações entre as taxas de emissão de fótons avaliadas por espectrometria gama, e o método de Point Kernel, que correlaciona a atividade de uma fonte com as taxas de dose a várias distâncias. O método descrito pode ser utilizado para determinar de modo rotineiro o inventário radioisotópico destes filtros, dispensando análises radioquímicas destrutivas, e a necessidade de calibração da geometria de medição. / The admission of radioactive waste in a final repository depends among other things on the knowledge of the radioisotopic inventory of the waste. To obtain this information it is necessary make the primary characterization of the waste so that it is composition is known, to guide the next steps of radioactive waste management. Filter cartridges that are used in the water polishing system of IEA-R1 research reactor is one of these wastes. The IEA-R1 is a pool-type research reactor, operating between 2 and 5 MW that uses water as coolant, moderator and biological shield. Besides research, it is used for production of radioisotopes and irradiation of samples with neutron and gamma beams. It is located in the Nuclear and Energy Research Institute at the University of Sao Paulo campus. The filter cartridges are used to retain particles that are suspended in the cooling water. When filters become saturated and are unable to maintain the flow within the established limits, they are replaced and disposed of as radioactive waste. After a period of decay, they are sent to the Radioactive Waste Management Department. The aim of this work is to present the studies to determine the activity of gamma emitters present in the cartridge filters. The activities were calculated using the dose rates measured with handheld detectors, after the ratios of the emission rates of photons were evaluated by gamma spectrometry, by the Point Kernel method, which correlates the activity of a source with dose rates at various distances. The method described can be used to determine routinely the radioactive inventory of these filters, avoiding the necessity of destructive radiochemical analysis, or the necessity of calibrating the geometry of measurement.

A aceitação de rejeitos radioativos em um repositório final depende, entre outras coisas, do conhecimento do inventário radioisotópico presente neles. Para obter essa informação, é necessário fazer a caracterização primária dos rejeitos de modo que a composição seja conhecida e oriente os passos seguintes da gestão. Os filtros cartucho que são utilizados no sistema de retratamento de água do reator de pesquisa IEA-R1 é um desses rejeitos. O IEA-R1 é um reator de pesquisa do tipo piscina, operando entre 2 e 5 MW, que utiliza a água como líquido de arrefecimento, moderador e blindagem biológica Além do seu uso em pesquisa, também é utilizado para produzir radioisótopos e irradiar amostras. Ele está localizado no Instituto de Pesquisas Energéticas e Nuclear, no campus da Universidade de São Paulo. Os filtros cartucho são utilizados para reter o material particulado em suspensão presente na água. Quando os filtros ficam saturados e são incapazes de manter o fluxo dentro dos limites estabelecidos, eles são substituídos e descartados como rejeito radioativo. Após um período de espera para o decaimento da atividade, são enviados para Gerência de Rejeitos Radioativos (GRR). O objetivo deste trabalho é apresentar os estudos realizados para determinar a atividade dos emissores gama presentes nos filtros cartucho. As atividades foram calculadas utilizando as taxas de dose medidas com detectores portáteis, as relações entre as taxas de emissão de fótons avaliadas por espectrometria gama, e o método de Point Kernel, que correlaciona a atividade de uma fonte com as taxas de dose a várias distâncias. O método descrito pode ser utilizado para determinar de modo rotineiro o inventário radioisotópico destes filtros, dispensando análises radioquímicas destrutivas, e a necessidade de calibração da geometria de medição. / The admission of radioactive waste in a final repository depends among other things on the knowledge of the radioisotopic inventory of the waste. To obtain this information it is necessary make the primary characterization of the waste so that it is composition is known, to guide the next steps of radioactive waste management. Filter cartridges that are used in the water polishing system of IEA-R1 research reactor is one of these wastes. The IEA-R1 is a pool-type research reactor, operating between 2 and 5 MW that uses water as coolant, moderator and biological shield. Besides research, it is used for production of radioisotopes and irradiation of samples with neutron and gamma beams. It is located in the Nuclear and Energy Research Institute at the University of Sao Paulo campus. The filter cartridges are used to retain particles that are suspended in the cooling water. When filters become saturated and are unable to maintain the flow within the established limits, they are replaced and disposed of as radioactive waste. After a period of decay, they are sent to the Radioactive Waste Management Department. The aim of this work is to present the studies to determine the activity of gamma emitters present in the cartridge filters. The activities were calculated using the dose rates measured with handheld detectors, after the ratios of the emission rates of photons were evaluated by gamma spectrometry, by the Point Kernel method, which correlates the activity of a source with dose rates at various distances. The method described can be used to determine routinely the radioactive inventory of these filters, avoiding the necessity of destructive radiochemical analysis, or the necessity of calibrating the geometry of measurement.

Trajectories of decline have been described in coral reefs throughout the Indo-Pacific region, with long-term losses of abundance, diversity and habitat structure. Since European settlement of the Queensland coastline in the mid-18th century, widespread changes in land use have occurred within Great Barrier Reef (GBR) catchments (e.g. extensive land clearing, agriculture and grazing). Despite direct and indirect evidence indicating decline of inshore reefs, it has proven difficult to ascertain links between land use changes, terrestrial discharge, water quality and the decline of coral reefs at regional scales, and the contributions of anthropogenic influences to the disturbance regimes of inshore reefs remains highly controversial. This thesis uses palaeoecological reconstruction of coral assemblages and high-precision U-Series dating to examine changes in community structure of inshore coral reefs in the Palm Islands region across decadal and centennial scales. Comparisons of modern and historical coral assemblages provide evidence of a collapse of Acropora coral communities at Pelorus Reef in the early 20th Century. Fossil assemblages in an adjacent site at Pelorus provide further evidence of an extrinsic shift from historical Acropora assemblages to more sediment-tolerant corals in modern assemblages, a change without precedence in 800 years of record. Sediment cores (2-5m length) were extracted from Pandora and Havannah reefs to determine long-term rates of reef growth throughout the late Holocene. Computer Axial Tomography (CAT) scans of cores revealed a framework dominated by coral fragments, and U-Series dating of corals revealed rapid and continuous reef growth at both reefs throughout the last 1000 yrs. Comparisons of reef accretion (m ka-1) from cores with published accretion rates from early-mid Holocene inshore GBR reefs show that reef slope environments are now accreting at rates equal to and exceeding those of the last 8000 years. This result contradicts assumptions that inshore reefs are undergoing or have undergone natural trajectories of geomorphic decline. A bayesian approach to determine stability of coral communities from the Pandora and Havannah cores indicates that those coral communities have existed in stable states for upwards of 400yrs, punctuated by periods of instability. Contrary to some paradigms of biodiversity, the high diversity communities were unstable on centennial scales, 4 yet the low diversity assemblages did not necessarily confer stability to these assemblages. Growth rates of inshore reefs were independent of diversity or community structure. From a management perspective, these results provide a longer-term (decades to centuries) understanding of coral community dynamics on inshore reefs of the GBR that provides a basis for detecting and understanding changes following European settlement, and a baseline for the management and potential restoration of coral communities at local and regional scales.

Made available in DSpace on 2014-06-11T19:24:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-01-29Bitstream added on 2014-06-13T19:52:24Z : No. of bitstreams: 1 penteado_msx_me_botfca.pdf: 2342181 bytes, checksum: a7406f91460a51ad9cadd5d5778971e5 (MD5) / Neste trabalho é apresentado todo o desenvolvimento do Sistema Aton, sistema automatizado de aquisição e tratamento de dados para radiometria solar, bem como as necessidades e carências que levaram a sua construção. Em sua metodologia, são implementadas soluções para problemas rotineiros identificados na Estação de Radiometria Solar da UNESP de Botucatu - SP. O sistema Aton é um software com ambiente gráfico simplificado ao operador inicialmente desenvolvido para operar em plataforma Windows Vista de 32 Bits. O programa pode ser usado em estações meteorológicas e climatológicas e também como suporte na medição e avaliação da disponibilidade de radiação solar. O programa foi desenvolvido em módulos com rotinas de controle de qualidade de dados, de cálculo e estimativa de efemérides solares. São apresentados detalhes da operação do software com uma descrição completa de todos os módulos contendo as rotinas e técnicas usadas. Os módulos desenvolvidos permitem a importação automatizada da partição temporal instantânea e cálculo das energias das partições horária, diária e média mensal. Como as componentes de irradiância solar estão relacionadas ao sensor de qual se origina suas medidas, o sistema Aton estoca separadamente uma partição instantânea, horária,diária e média mensal para cada sensor da estação de radiometria solar em banco de dados, o que agiliza a recuperação de informações e mantém flexibilidade para alterações na estação de radiometria solar. O sistema resolve ainda o problema interpretação de dados em arquivos com layout variável causado por alterações na estrutura da estação solarimétrica no período de 28 de fevereiro de 1999 até 31 de agosto de 2008. / In this work was presented all development in Aton System, acquisition automatizated system and datas treatment to solar radiometric, as well as the needs and lacks that took your construction. In your methodology, were implemented solutions to routine problems identified in the Solar Radiometric Station at UNESP from Botucatu-SP. The Alton system is one software with graphic enviroment simplified to the operator initially developed to operate in Windows Vista platform of 32 Bits. The program can be used in meteorologic and climatologic stations and also like measuring and assessment support of solar radiation availability. The program was developed in modules with routines of datas, calculus and estimate of solars event control quality. Were presented details of the software operation with a complete description of all the modules containing the used routines and techniques. The modules developed allow the automated importing of the instantaneous time partition and energies calculus of the hourly, dairly and monthly average partition. As the radiance solar components are related to the sensor of which comes their measures, the Aton system store separately one instantaneous hourly, dairly and monthly average partition for each sensor solar radiometric station in databases, that streamline the information´s recovery and keep flexibility to changes in the solar radiometric station. The system still solve the datas interpretation problem in files with variable layout caused by changes in the solarimetric station structure in the period from February 28th,1999 to August 31st, 2008.

Orientador: João Francisco Escobedo / Banca: Dinival Martins / Banca: Alexandre Dal Pai / Resumo: Neste trabalho é apresentado todo o desenvolvimento do Sistema Aton, sistema automatizado de aquisição e tratamento de dados para radiometria solar, bem como as necessidades e carências que levaram a sua construção. Em sua metodologia, são implementadas soluções para problemas rotineiros identificados na Estação de Radiometria Solar da UNESP de Botucatu - SP. O sistema Aton é um software com ambiente gráfico simplificado ao operador inicialmente desenvolvido para operar em plataforma Windows Vista de 32 Bits. O programa pode ser usado em estações meteorológicas e climatológicas e também como suporte na medição e avaliação da disponibilidade de radiação solar. O programa foi desenvolvido em módulos com rotinas de controle de qualidade de dados, de cálculo e estimativa de efemérides solares. São apresentados detalhes da operação do software com uma descrição completa de todos os módulos contendo as rotinas e técnicas usadas. Os módulos desenvolvidos permitem a importação automatizada da partição temporal instantânea e cálculo das energias das partições horária, diária e média mensal. Como as componentes de irradiância solar estão relacionadas ao sensor de qual se origina suas medidas, o sistema Aton estoca separadamente uma partição instantânea, horária,diária e média mensal para cada sensor da estação de radiometria solar em banco de dados, o que agiliza a recuperação de informações e mantém flexibilidade para alterações na estação de radiometria solar. O sistema resolve ainda o problema interpretação de dados em arquivos com layout variável causado por alterações na estrutura da estação solarimétrica no período de 28 de fevereiro de 1999 até 31 de agosto de 2008. / Abstract: In this work was presented all development in Aton System, acquisition automatizated system and datas treatment to solar radiometric, as well as the needs and lacks that took your construction. In your methodology, were implemented solutions to routine problems identified in the Solar Radiometric Station at UNESP from Botucatu-SP. The Alton system is one software with graphic enviroment simplified to the operator initially developed to operate in Windows Vista platform of 32 Bits. The program can be used in meteorologic and climatologic stations and also like measuring and assessment support of solar radiation availability. The program was developed in modules with routines of datas, calculus and estimate of solars event control quality. Were presented details of the software operation with a complete description of all the modules containing the used routines and techniques. The modules developed allow the automated importing of the instantaneous time partition and energies calculus of the hourly, dairly and monthly average partition. As the radiance solar components are related to the sensor of which comes their measures, the Aton system store separately one instantaneous hourly, dairly and monthly average partition for each sensor solar radiometric station in databases, that streamline the information's recovery and keep flexibility to changes in the solar radiometric station. The system still solve the datas interpretation problem in files with variable layout caused by changes in the solarimetric station structure in the period from February 28th,1999 to August 31st, 2008. / Mestre

A detailed geochronological and geochemical study has been undertaken on selected sediment cores from four lowland coastal marsh environments in Argyll, Western Scotland. This region of northern Britain has experienced differential crustal uplift and relative sea-level changes throughout the Holocene in response to glacio-isostatic adjustment. The complex interplay between land movements and relative sea-level continues to influence the morphological development of the Scottish coast. The study of lowland inter-tidal sedimentary environments from this region provides an opportunity to investigate the linkages between current estimated crustal movements, regional relative sea-level rise and the evolution of contemporary coastal saltmarshes derived from the record of historical sedimentation. The four sites are located across a ca. 70 km transect extending from the head of Loch Scridain (western Isle of Mull), across the Firth of Lorne to the head of Loch Etive, (mainland Argyll). Vertical activity distributions of the natural radionuclide 21OPb and anthropogenic isotopes (137Cs and 243Am) have been measured and are used to assess the depositional history of marsh sediment accumulation recorded in the four marsh cores. Down-core activity profiles of radionuclides are only reliable as a means of modelling recent marsh evolution provided no early-diagenetic (redox) reactions have compromised the historical depositional record within the marsh sediments. Solid-phase major and trace element down-core geochemical distributions provide a means of assessing the extent to which post-depositional (redox) reactions may have influenced the reliability of the radiometric dating methods. Marsh sediment geochemistry also serves as a useful proxy for identifying compositional variability over the period of marsh development investigated. Dating of the Argyll saltmarsh cores indicates that over the period corresponding to mature marsh conditions rates of sedimentation vary significantly across the study area. At Loch Scridain an average rate of 1.1 mm yr-1 corresponding to an historical period of ca. 130 years is recorded. Comparison with estimated rates of regional sea-level rise suggest an established asymptotic relationship between marsh accretion and coastal forcing, implying historical crustal stability at this site. At sites within the Firth of Lome (Loch Don and Loch Creran) average rates of 2.5 and 3.3 mm yr-1 are recorded for the ca. 70 year period to 1995 with a figure of 2.2 mm yr-1 recorded in the marsh core from the head of Loch Etive. These values are well in excess of estimated relative sea-level rise during the twentieth century suggesting that these marshes may not yet have reached full equilibrium with sea-level. Microfossil analysis of the Loch Etive core helps to identify a more complex depositional history with an underlying trend of marine transgression for the ca. 110 year period of marsh development recorded in these sediments. Over the most recent period of marsh development (ca. 5 years) a significant increase in the rate of marsh sedimentation at all sites is recorded. This signifies the response of these marshes to a very recent increase in the rate of relative sea-level rise across the region. Comparison with available storm frequency data indicates that the evolution of these marsh environments have not been subject to the influence of significant storm activity over the last in the late Twetieth century. The findings suggest that the more clastic sedimentary composition of the Argyll marshes results in these inter-tidal areas being extremely sensitive to changes in coastal forcing (sea-level rise). The implications of recent relative sea-level rise, current vertical crustal movements and future coastal management are discussed.

Detecting changes in land cover through time using remotely sensed imagery is a powerful application that has seen increased use as imagery has become more widely available and inexpensive. Before a time series of remotely sensed imagery can be used for change detection, images must first be standardized for effects outside of real surface change. This thesis established a validation protocol to evaluate the effectiveness of an automated technique for normalizing temporally separate but spatially coincident imagery. Using the concept of pseudo-invariant features between master-slave image pairs, spatially coincident dark and bright points are identified from images and a regression equation is calculated to normalize slave images to a master. I used two sets of imagery to test the performance of the standardization process, a spatially coincident, but temporally variable time series, and spatially and temporally variable images. I tested the underlying statistical assumptions of this approach, and performed simple image subtraction to validate the reduction of master-slave differences using invariant locations. In addition I tested the possibility of reducing between-sensor differences by applying simple linear regression to comparable bands of MSS and TM sensors. Image subtraction showed decreases in master-slave differences as a result of the standardization process, and the process behaved appropriately when there should be no difference between master and slave images (adjacent, but temporally identical imagery). I also found that comparable bands between MSS and TM sensors are similar enough that linear regression may not significantly reduce between-sensor differences.

The diploma theses focused on the topic of removing spectral aberration of sensor. The anomaly is being called spectral smile effect, or spectral curvature. Usually are with this artifact affected hyperspectral sensors, whose sensing is based on principle corresponding to pushbroom scanner. The defect occurs in the data as brightness gradient in the cross-track direction to the sensor flight and affects the object's spectral characteristics shape. Removing is important particularly in case of applying atmospheric correction algorithm, which are being degraded with presence of this defect. The work contents description of current methods used for detecting and eliminating this anomaly. The work is closer focused on the methods removing the defect based on own measured data without use of calibration targets. There is being examined sensitivity of the methods on the scene perception character, meaning heterogeneity of the scene and other outside influence. One of the methods is deeply processed resulting in increasing quality of the method for removing the defect.