940 resultados para Baxter-King, ciclos económicos, tendencia, Hodrick-Prescott, series.
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Pós-graduação em Engenharia Mecânica - FEG
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[ES]El mantenimiento de observaciones continuadas, durante largos períodos de tiempo en un mismo área, es una estrategia científica y logística de gran interés oceanográfico. El estudio detallado de las series así establecidas, nos permitirá conocer los cambios temporales que tienen lugar tanto en la fisica, como en la biogeoquímica oceánica, y los procesos que ejercen el control de los mismos. Dentro de esta escala temporal, la base de datos hidrográficos que resulta nos ayudará a establecer los ciclos estacionales y los ciclos interanuales del conjunto de parámetros hidrográficos y geoquímicos medidos. El Archipiélago Canario está considerado, dada la combinación de procesos de larga escala que se dan, como una zona óptima para estudios de las aguas oceánicas a escala global. Se encuentra rodeado de aguas profundas inmersas en el régimen de recirculación Este de la Corriente del Golfo, constituido por la Corriente de Canarias, influenciado por el afloramiento del Noroeste Africano y por la deposición de partículas eólicas desde el Sahara.El programa ESTOC supone una contribución a los proyectos internacionales y multidisciplinarios WOCE (World Ocean Circulation Experiment) y JGOFS (Joint Global Ocean Flux Study) que pretenden resolver el problema científico que supone la escasez de información sobre lo que está ocurriendo en los océanos a escala global.
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Máster en Gestión Sostenible de Recursos Pesqueros
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The pattern of contact sensitization to the supposedly most important allergens assembled in the baseline series differs between countries, presumably at least partly because of exposure differences. Objectives. To describe the prevalence of contact sensitization to allergens tested in consecutive patients in the years 2007 and 2008, and to discuss possible differences.
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BACKGROUND: Continual surveillance based on patch test results has proved useful for the identification of contact allergy. OBJECTIVES: To provide a current view on the spectrum of contact allergy to important sensitizers across Europe. PATIENTS/METHODS: Clinical and patch test data of 19 793 patients patch tested in 2005/2006 in the 31 participating departments from 10 European countries (the European Surveillance System on Contact Allergies' (ESSCA) www.essca-dc.org) were descriptively analysed, aggregated to four European regions. RESULTS: Nickel sulfate remains the most common allergen with standardized prevalences ranging from 19.7% (central Europe) to 24.4% (southern Europe). While a number of allergens shows limited variation across the four regions, such as Myroxylon pereirae (5.3-6.8%), cobalt chloride (6.2-8.8%) or thiuram mix (1.7-2.4%), the differences observed with other allergens may hint on underlying differences in exposures, for example: dichromate 2.4% in the UK (west) versus 4.5-5.9% in the remaining EU regions, methylchloroisothiazolinone/methylisothiazolinone 4.1% in the South versus 2.1-2.7% in the remaining regions. CONCLUSIONS: Notwithstanding residual methodological variation (affecting at least some 'difficult' allergens) tackled by ongoing efforts for standardization, a comparative analysis as presented provides (i) a broad overview on contact allergy frequencies and (ii) interesting starting points for further, in-depth investigation.
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The accuracy of Global Positioning System (GPS) time series is degraded by the presence of offsets. To assess the effectiveness of methods that detect and remove these offsets, we designed and managed the Detection of Offsets in GPS Experiment. We simulated time series that mimicked realistic GPS data consisting of a velocity component, offsets, white and flicker noises (1/f spectrum noises) composed in an additive model. The data set was made available to the GPS analysis community without revealing the offsets, and several groups conducted blind tests with a range of detection approaches. The results show that, at present, manual methods (where offsets are hand picked) almost always give better results than automated or semi‒automated methods (two automated methods give quite similar velocity bias as the best manual solutions). For instance, the fifth percentile range (5% to 95%) in velocity bias for automated approaches is equal to 4.2 mm/year (most commonly ±0.4 mm/yr from the truth), whereas it is equal to 1.8 mm/yr for the manual solutions (most commonly 0.2 mm/yr from the truth). The magnitude of offsets detectable by manual solutions is smaller than for automated solutions, with the smallest detectable offset for the best manual and automatic solutions equal to 5 mm and 8 mm, respectively. Assuming the simulated time series noise levels are representative of real GPS time series, robust geophysical interpretation of individual site velocities lower than 0.2–0.4 mm/yr is therefore certainly not robust, although a limit of nearer 1 mm/yr would be a more conservative choice. Further work to improve offset detection in GPS coordinates time series is required before we can routinely interpret sub‒mm/yr velocities for single GPS stations.