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Entropy Filter for Anomaly Detection with Eddy Current Remote Field SensorsSheikhi, Farid 14 May 2014 (has links)
We consider the problem of extracting a specific feature from a noisy signal generated
by a multi-channels Remote Field Eddy Current Sensor. The sensor is installed on a
mobile robot whose mission is the detection of anomalous regions in metal pipelines.
Given the presence of noise that characterizes the data series, anomaly signals could
be masked by noise and therefore difficult to identify in some instances. In order
to enhance signal peaks that potentially identify anomalies we consider an entropy
filter built on a-posteriori probability density functions associated with data series.
Thresholds based on the Neyman-Pearson criterion for hypothesis testing are derived.
The algorithmic tool is applied to the analysis of data from a portion of pipeline with
a set of anomalies introduced at predetermined locations. Critical areas identifying
anomalies capture the set of damaged locations, demonstrating the effectiveness of
the filter in detection with Remote Field Eddy Current Sensor.
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Entropy Filter for Anomaly Detection with Eddy Current Remote Field SensorsSheikhi, Farid January 2014 (has links)
We consider the problem of extracting a specific feature from a noisy signal generated
by a multi-channels Remote Field Eddy Current Sensor. The sensor is installed on a
mobile robot whose mission is the detection of anomalous regions in metal pipelines.
Given the presence of noise that characterizes the data series, anomaly signals could
be masked by noise and therefore difficult to identify in some instances. In order
to enhance signal peaks that potentially identify anomalies we consider an entropy
filter built on a-posteriori probability density functions associated with data series.
Thresholds based on the Neyman-Pearson criterion for hypothesis testing are derived.
The algorithmic tool is applied to the analysis of data from a portion of pipeline with
a set of anomalies introduced at predetermined locations. Critical areas identifying
anomalies capture the set of damaged locations, demonstrating the effectiveness of
the filter in detection with Remote Field Eddy Current Sensor.
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Análise múltipla escala de sensores remotos óticos e de microondas aplicados ao estudo da Neotectônica na região de Manaus, AmazonasPalha, Willian Sérgio Marques 21 August 2006 (has links)
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Previous issue date: 2006-08-21 / The tectonics models purpose for the Amazon region are adaptation of region model of others places in the brazil and world and needing the work filed. the most part of the study achieved is difficult by scarcity of good outcrops, therewithal maps thematics and cartoghaphy need be to update. Today is notorious which remote sensor aerotransport or orbit are tools very important in the obtaining of information and generation of new product, as to confirm in the tectonics movements at a determine region of the study. The setting geomorphologic of the Manaus region and adjoining is result of geologic processes initiated in period remote which yet act. Appreciation which remote sensing data from the platform orbit are an valuable information in the geological mapping, ore resource, engineering geology and projection of
the environment. With previous images satellite, this work focused as generals aim of generation new product of remote sensing, which can be used in local an regional geological
mapping, to establish cretirion methodology base on interpretation of product integration of Landsat-5 images satellite, Radasart-1, JERS-1, SRTM and IKONOS, showing the main advantages and limitation of the data of high, mean and low spatial resolution. To obtain of object proposal (to go) employee technic and method of photogeological interpretion
conventional and aplication of modern technic processing digital of image, with detach into automatic lineament extraction. The results to obtein to demostrate which a utilisatio combined of technic of integrate the multi-source data, processing digital of image and photogeological interpretion are efficacius at constrution tectonic models local which assistant in compreension of models accept regionally. At region Manaus City go possible to characterize seven blocks tectonic. The study demonstract which at region of Manaus is powerful controller by structural alilinement and lineament. This feature have direction preferential N40-50W by river Tarumã-Mirim, Puraquequara, Preto da Eva, Urubu e Uatumã and N10-20E in the river Cuieiras e Tarumã-Açú, of which limited the tectonic block individualily. Subordinate is identificable an assemblage marked for alilinement for less of
direction N40-60E, which control the tributary for less of river principal. Independety of tectonic models proposed whether in scale continent, regional or local, by the area of Manaus
and adjoins, whather deduce of work is the utilizatio the new product and computtetion tools increase an efficacy of stractural analysis and contribute by construct of tectonic models greater consistent. Evidently which the methodology present hasn make use of isolatly, but naturally in association with the classic technic of interpretion visual and essentially with data survey of field. / Os modelos tectônicos propostos para a região amazônica são adaptações de modelos de outras regiões do país e do mundo carecem obviamente de levantamentos comprobatórios de
campo. A maioria destes estudos de caso são invariavelmente agravados pela pequena quantidade e qualidade dos afloramentos rochosos, além da falta de atualizações recente de mapas temáticos e cartográficos. Hoje é notório que sensores remotos aerotransportados ou orbitais são ferramentas de suma importância na obtenção de informações e geração de novos produtos, a fim de confirmar os movimentos tectônicos em uma determinada região de estudo.
O Quadro geomorfológico da região de Manaus e adjacências resultam de processos geológicos iniciados em períodos remotos que ainda não cessaram. Considerando que a
utilização de dados de sensoriamento remoto provenientes de plataformas orbitais são um valioso instrumento no mapeamento geológico, na procura de recursos minerais, na geologia de engenharia; e no planejamento ambiental. Neste contexto, a presente dissertação teve como objetivos principais a geração de novos produtos de sensoriamento remoto, a partir de imagens de satélite, que possam ser utilizados no mapeamento geológico local e regional e
estabelecer critérios metodológicos baseados na interpretação de produtos integrados de imagens dos satélites Landsat-5, Radarsat-1, JERS-1, SRTM e IKONOS. e por fim apresentar as principais vantagens e limitações do uso de dados de alta, média e baixa resolução espacial. Para alcançar os objetivos propostos foram empregados técnicas e métodos de fotointerpretação geológica convencional e de aplicação de técnicas modernas de processamento digital de imagens, com destaque para a extração automática de lineamentos. Os resultados obtidos demonstram que a utilização conjunta de técnicas de integração de dados multifonte, processamento digital de imagens e de fotointerpretação são eficazes para a construção de modelos tectônicos locais que auxiliam na compreensão dos modelos adotados regionalmente. Na região da cidade de Manaus foi possível caracterizar sete blocos tectônicos. O estudo demonstrou que a região de Manaus está fortemente controlada por alinhamentos e lineamentos estruturais. Estas feições têm direções preferenciais N40-50W para rios Tarumã-Mirim, Puraquequara, Preto da Eva, Urubu e Uatumã e N10-20E pelos rios Cuieiras e Tarumã-Açú, os quais limitam os blocos tectônicos individualizados. Secundariamente é identificado um conjunto bem marcante de alinhamentos menores de direção N40-60E, que controlam os afluentes menores dos rios principais. Independemente dos modelos tectônicos propostos quer na escala continental, regional ou local, para a área de Manaus e adjacências, o que depreende do trabalho realizado é que a utilização de novos produtos e ferramentas computacionais aumenta a eficácia da análise estrutural e contribui para a construção de modelos tectônicos mais consistentes. É Evidente que a metodologia
apresentada não deve ser utilizada isoladamente, mas em associação com as técnicas clássicas de interpretação visual e, essencialmente, com dados de levantamentos de campo.
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Calibration of Snowmaking Equipment for Efficient Use on Virginia's Smart RoadShea, Edward 16 September 1999 (has links)
Virginia's Smart Road, to be completed by early 2000, is a test bed for numerous research activities including snow and ice control, remote sensor testing, snow removal management, safety and human factors, and vehicle dynamics. An all-weather testing system will feature 75 automated snowmaking towers. In order to provide timely and repeatable weather scenarios, equipment operators will need to understand fully the limitations and capabilities of the snowmaking system.
The research presented herein addresses the hydraulic and hydrologic variables and design methodology to implement efficient snowmaking at a transportation research facility. Design variables include nozzle configuration, water pressure and flowrate, compressed air pressure and flowrate, tower orientation, snow inducer concentration, water and compressed air temperature, and ambient weather conditions. Testing and data collection was performed at the Snow Economics, Inc. research and development site at Seven Springs Mountain Resort in Champion, PA. The results of this work will be used to guide the operators of the Smart Road on the most efficient use of the snowmaking equipment. / Master of Science
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