991 resultados para Bird surveying method
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Bibliography: leaves 46-48.
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No hemisfério norte, o censo de aves é fundamental para gerar informações que auxiliam na compreensão de tendências populacionais. Tais censos, devido à marcada sazonalidade deste hemisfério, são realizados durante dois momentos distintos: na estação reprodutiva (aves residentes) e no inverno (quando as aves migratórias deixam determinadas regiões). Na região neotropical, porém, dependendo da localidade, as aves podem se reproduzir durante qualquer ou vários períodos do ano; podem ou não migrar, e aquelas que o fazem podem apresentar um padrão assincrônico. Em contraste com o hemisfério norte, tendências populacionais são desconhecidas, bem como o impacto das taxas rápidas de urbanização e desmatamento, que também são pouco monitoradas. Para melhor entender padrões temporais de riqueza e abundância de aves, e avaliar como um censo similar pode ser implementado na América tropical, foram utilizados pontos de escuta ao longo de 12 meses em uma localidade no Estado de São Paulo, sudeste do Brasil. Os censos ocorreram duas vezes por dia (manhãs/tardes) em uma floresta semidecidual ao longo de transecções com 10 pontos (20 pontos por dia) distantes 200 m entre si e com raio de detecção limitado em 100 m. Ambas as riquezas e abundâncias de aves foram maiores durante as manhãs, mas as curvas de acumulação sugerem que os censos vespertinos com maior esforço amostral podem fornecer resultados similares aos censos matutinos. Riqueza e abundância das aves não variam de acordo com estações (i.e., sem padrão aparente entre reprodução e migração), enquanto espécies exclusivas foram encontradas todos os meses e relativamente poucas espécies (20%) foram registradas em todos os meses do ano. Durante este ano, 84% de todas as aves florestais da área estudada foram registradas. Sugerimos que a metodologia de pontos de escuta pode ser utilizada à semelhança dos censos do hemisfério norte. Recomendamos ainda que o esforço amostral em transecções deva incluir ao menos 20 pontos, e que o início da contagem das aves deva ser sazonal, utilizando o período de migração das espécies austrais (e os seis meses seguintes) para coordenar pontos de escuta. Por último, sugerimos que os censos no Brasil e até mesmo na América Latina podem ajudar no entendimento de tendências populacionais, mas também demandam maior esforço do que o observado em latitudes temperadas, devido à maior riqueza de espécies e diferenças nas dinâmicas de reprodução e migração. Por meio do uso de censos de aves coordenados poderá ser desenvolvida uma técnica para os trópicos que irá gerar informações que permitam acompanhar tendências populacionais, com benefícios para a conservação das aves, similarmente aos censos realizados em países do hemisfério norte.
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We demonstrate that the parametric resonance in a magnetic quadrupole trap can be exploited to cool atoms by using Bird's method. In our programme the parametric resonance was realized by anisotropically modulating the trap potential. The modulation frequency dependences of temperature and fraction of the trapped atoms are explored. Furthermore, the temperature after the modulation as functions of the modulation amplitude and the mean elastic collision time are also studied. These results are valuable for the experiment of parametric resonance in a quadrupole trap.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Un plan cartográfico es un proceso contradictorio en el cual intervienen decisiones técnicas y políticas que pueden cambiar e incluso modificar los objetivos iniciales del plan. Sin embardo, la historiografía clásica de la cartografía sostiene que la toma de tales decisiones es el resultado de medidas únicamente científicas y técnicas en las que no existen intereses ni contradicciones políticas. En este trabajo intentamos rastrear -en las etapas de la producción cartográfica argentina- los momentos en los que la ciencia y la política se entrelazan de tal manera que son constitutivas de la ciencia cartográfica. Para ello tomamos los proyectos cartográficos del IGM: el Plan de la Carta y la Carta Militar Provisional; y la determinación geodésica del DATUM altimétrico que se llevó a cabo en torno a la Comisión para la Medición del Arco de Meridiano
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Un plan cartográfico es un proceso contradictorio en el cual intervienen decisiones técnicas y políticas que pueden cambiar e incluso modificar los objetivos iniciales del plan. Sin embardo, la historiografía clásica de la cartografía sostiene que la toma de tales decisiones es el resultado de medidas únicamente científicas y técnicas en las que no existen intereses ni contradicciones políticas. En este trabajo intentamos rastrear -en las etapas de la producción cartográfica argentina- los momentos en los que la ciencia y la política se entrelazan de tal manera que son constitutivas de la ciencia cartográfica. Para ello tomamos los proyectos cartográficos del IGM: el Plan de la Carta y la Carta Militar Provisional; y la determinación geodésica del DATUM altimétrico que se llevó a cabo en torno a la Comisión para la Medición del Arco de Meridiano
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Un plan cartográfico es un proceso contradictorio en el cual intervienen decisiones técnicas y políticas que pueden cambiar e incluso modificar los objetivos iniciales del plan. Sin embardo, la historiografía clásica de la cartografía sostiene que la toma de tales decisiones es el resultado de medidas únicamente científicas y técnicas en las que no existen intereses ni contradicciones políticas. En este trabajo intentamos rastrear -en las etapas de la producción cartográfica argentina- los momentos en los que la ciencia y la política se entrelazan de tal manera que son constitutivas de la ciencia cartográfica. Para ello tomamos los proyectos cartográficos del IGM: el Plan de la Carta y la Carta Militar Provisional; y la determinación geodésica del DATUM altimétrico que se llevó a cabo en torno a la Comisión para la Medición del Arco de Meridiano
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During the Peninsular War, Napoleon's and Wellington's armies were aware of the lack of precision in the maps of Spain and its provinces that appeared in Tomas Lopez \s Geographical Atlas of Spain. The errors were due to the non-topographical surveying method he used which he had learned from his teacher Jean Baptiste Bourguignon D 'Anville. To map all of the Spanish provinces, Tomas Lopez divided them into circles of three leagues in diameter (16,718 m), taking a particular town as the centre. He asked the town's priest to draw a map of the territory and to complete a questionnaire that Tomas Lopez sent to him. The priest was to return the two documents after he had completed them. Subsequently, at his desk, Tomas Lopez used the maps and reports as well as other graphic and written sources from various locations to make an outline of each map. Next, he made a mosaic that served as a pattern for drawing the final provincial map. We will see the way that this method was applied in two concrete cases: the villages ofChavaler and Monteagudo, situated in the Spanish province of Soria, and verify their degree of accuracy. We will use the maps drawn by the priests in 1767, the final map of the province which was published in 1804 by Tomás López, and a current map of the province showing the angular and linear errors in Lopez \s map.
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Due to rapid and continuous deforestation, recent bird surveys in the Atlantic Forest are following rapid assessment programs to accumulate significant amounts of data during short periods of time. During this study, two surveying methods were used to evaluate which technique rapidly accumulated most species (> 90% of the estimated empirical value) at lowland Atlantic Forests in the state of São Paulo, southeastern Brazil. Birds were counted during the 2008-2010 breeding seasons using 10-minute point counts and 10-species lists. Overall, point counting detected as many species as lists (79 vs. 83, respectively), and 88 points (14.7 h) detected 90% of the estimated species richness. Forty-one lists were insufficient to detect 90% of all species. However, lists accumulated species faster in a shorter time period, probably due to the nature of the point count method in which species detected while moving between points are not considered. Rapid assessment programs in these forests will rapidly detect more species using 10-species lists. Both methods shared 63% of all forest species, but this may be due to spatial and temporal mismatch between samplings of each method.
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Mode of access: Internet.
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(Gt. Brit. Air survey committee. Professional papers, no. 8 Supplement)
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This paper presents the method and results of a survey of 27 of the 33 Australian universities teaching engineering education in late 2007, undertaken by The Natural Edge Project (hosted by Griffith University and the Australian National University) and supported by the National Framework for Energy Efficiency. This survey aimed to ascertain the extent of energy efficiency (EE) education, and to identify preferred methods to assist in increasing the extent to which EE education is embedded in engineering curriculum. In this paper the context for the survey is supported by a summary of the key results from a variety of surveys undertaken over the last decade internationally. The paper concludes that EE education across universities and engineering disciplines in Australia is currently highly variable and ad hoc. Based on the results of the survey, this paper highlights a number of preferred options to support educators to embed sustainability within engineering programs, and future opportunities for monitoring EE, within the context of engineering education for sustainable development (EESD).
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Acoustic sensors can be used to estimate species richness for vocal species such as birds. They can continuously and passively record large volumes of data over extended periods. These data must subsequently be analyzed to detect the presence of vocal species. Automated analysis of acoustic data for large numbers of species is complex and can be subject to high levels of false positive and false negative results. Manual analysis by experienced surveyors can produce accurate results; however the time and effort required to process even small volumes of data can make manual analysis prohibitive. This study examined the use of sampling methods to reduce the cost of analyzing large volumes of acoustic sensor data, while retaining high levels of species detection accuracy. Utilizing five days of manually analyzed acoustic sensor data from four sites, we examined a range of sampling frequencies and methods including random, stratified, and biologically informed. We found that randomly selecting 120 one-minute samples from the three hours immediately following dawn over five days of recordings, detected the highest number of species. On average, this method detected 62% of total species from 120 one-minute samples, compared to 34% of total species detected from traditional area search methods. Our results demonstrate that targeted sampling methods can provide an effective means for analyzing large volumes of acoustic sensor data efficiently and accurately. Development of automated and semi-automated techniques is required to assist in analyzing large volumes of acoustic sensor data. Read More: http://www.esajournals.org/doi/abs/10.1890/12-2088.1
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Bioacoustic monitoring has become a significant research topic for species diversity conservation. Due to the development of sensing techniques, acoustic sensors are widely deployed in the field to record animal sounds over a large spatial and temporal scale. With large volumes of collected audio data, it is essential to develop semi-automatic or automatic techniques to analyse the data. This can help ecologists make decisions on how to protect and promote the species diversity. This paper presents generic features to characterize a range of bird species for vocalisation retrieval. In the implementation, audio recordings are first converted to spectrograms using short-time Fourier transform, then a ridge detection method is applied to the spectrogram for detecting points of interest. Based on the detected points, a new region representation are explored for describing various bird vocalisations and a local descriptor including temporal entropy, frequency bin entropy and histogram of counts of four ridge directions is calculated for each sub-region. To speed up the retrieval process, indexing is carried out and the retrieved results are ranked according to similarity scores. The experiment results show that our proposed feature set can achieve 0.71 in term of retrieval success rate which outperforms spectral ridge features alone (0.55) and Mel frequency cepstral coefficients (0.36).