229 research outputs found
Assistência técnica em produção e armazenamento de arroz e milho no Alto Vale do Itajaí
No full textTCC (graduação) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Curso de Agronomia.O presente trabalho foi produto das atividades desenvolvidas ao longo do período de estagio realizada na Cooperativa Regional Agropecuária Alto Vale do Itajaí – CRAVIL, na matriz em Rio do Sul, estado de Santa Catarina, entre os meses de março e maio de 2012. No período pode-se, acompanhar diversas atividades relacionadas à cultura do arroz, do milho e do armazenamento dessas e de outras culturas. A cultura do milho tem apresentado aumento significativo no emprego de tecnologia seja na produção de semente ou na aplicação de fungicidas e controle químico de plantas infestantes, o que tem proporcionado maiores produtividades e alterações no custo de produção desta cultura. O arroz é uma cultura muito bem desenvolvida no Alto Vale do Itajaí, isto foi devido aos inúmeros estudos que foram realizados com a cultura na região, entre eles podem-se citar as competições entre cultivares, ensaios de valor de cultivo e estudos com aplicação de fungicidas. O armazenamento de grãos é uma das etapas mais importantes na cadeia produtiva e fundamental para a logística das produções. A metodologia emprega ao longo do estágio, envolveu visitas técnicas a produtores, participação em diversas avaliações a campo, levantamentos e avaliações de dados e participação de reuniões técnicas. Pôde-se observar que os estudos e as recomendações feitas pelos técnicos da Cravil são fundamentais para o desenvolvimento da agricultura no Alto Vale do Itajaí
Silicon photonics comb demultiplexer for elastic optical networks
No full textAn integrated reconfigurable optical comb demultiplexer for flexible-grid optical networks is demonstrated using high-order distributed feedback resonators realized in silicon-on-insulator technology. Low-loss tone isolation of nearly 30dB for a comb spacing of 12.5GHz is experimentally demonstrated in an ultra-compact layout, with potentials for operation with finer grids
A cervical dystonia successfully treated with tetrabenazine augmentation of clozapine and botox
No full textIntegrated Silicon-on-Insulator Optical Comb Demultiplexer for Elastic Optical Networks
No full textPractical deployment of elastic optical networks requires key enabling technologies supporting the miniaturization of flexible optical transponders for provisioning large-bandwidth services at low-cost per users. A silicon photonics (SiP) reconfigurable optical frequency comb (OFC) demultiplexer based on passive optical filtering exhibiting a minimum spurious tone rejection (STR) of nearly 30dB at 12.5GHz tone spacing is here reported. Low power penalty due to inter-channel crosstalk (IXT) originated by finite STR is observed. Improved filter designs for reduced IXT and/or operation at 6.25GHz comb spacing are experimentally and numerically verified. By monolithic integration with SiP OFC sources and I-Q modulators the scheme has potentials for realizing ultra-compact multiple-flow optical transmitters with adaptive bandwidth and channel spacing
Uncertainties in lung motion prediction relying on external surrogate: a 4DCT study in regular vs. irregular breathers.
No full textForecasting Realized Volatility Using A Nonnegative Semiparametric Model
No full textThis paper introduces a parsimonious and yet flexible nonnegative semiparametric model to forecast financial volatility. The new model extends the linear nonnegative autoregressive model of Barndorff-Nielsen & Shephard (2001) and Nielsen & Shephard (2003) by way of a power transformation. It is semiparametric in the sense that the dependency structure and distributional form of its error component are left unspecified. The statistical properties of the model are discussed and a novel estimation method is proposed. Simulation studies validate the new estimation method and suggest that it works reasonably well in finite samples. The out-of-sample performance of the proposed model is evaluated against a number of standard methods, using data on S&P 500 monthly realized volatilities. The competing models include the exponential smoothing method, a linear AR(1) model, a log-linear AR(1) model, and two long-memory ARFIMA models. Various loss functions are utilized to evaluate the predictive accuracy of the alternative methods. It is found that the new model generally produces highly competitive forecasts.Autoregression, nonlinear/non-Gaussian time series, realized volatility, semiparametric model, volatility forecast.
Forecasting Realized Volatility Using A Nonnegative Semiparametric Model
No full textThis paper introduces a parsimonious and yet flexible nonnegative semiparametric model to forecast financial volatility. The new model extends the linear nonnegative autoregressive model of Barndorff-Nielsen & Shephard (2001) and Nielsen & Shephard (2003) by way of a power transformation. It is semiparametric in the sense that the dependency structure and distributional form of its error component are left unspecified. The statistical properties of the model are discussed and a novel estimation method is proposed. Simulation studies validate the new estimation method and suggest that it works reasonably well in finite samples. The out-of-sample performance of the proposed model is evaluated against a number of standard methods, using data on S&P 500 monthly realized volatilities. The competing models include the exponential smoothing method, a linear AR(1) model, a log-linear AR(1) model, and two long-memory ARFIMA models. Various loss functions are utilized to evaluate the predictive accuracy of the alternative methods. It is found that the new model generally produces highly competitive forecasts.Autoregression, nonlinear/non-Gaussian time series, realized volatility, semiparametric model, volatility forecast
Wideband Single-Sideband Suppressed-Carrier Modulation with Silicon Photonics Optical Filters
No full textOptical single-sideband suppressed-carrier (SSBSC) modulation based on advanced silicon photonics (SiP) optical filter is experimentally demonstrated. Wideband frequency shift of 2 Gb/s modulated data over a 30 GHz range spanning from the X to the Ka bands with large side-mode suppression ratio up to more than 30 dB is reported. The scheme can potentially be updated for operation up to the mm-wave band and broadband signal modulation. The impact of the filter phase response is assessed by transmission over 60 km of standard single mode fiber of the generated SSB-SC signal which resulted in moderate power penalty of ~0.5 dB in respect to SSB-CS data obtained using commercial I-Q modulator. The scheme is simple and stable and suitable for realizing a photonic integrated circuit with minimized footprint by monolithic integration of the filter with phase/amplitude modulators and other functional elements in silicon-on-insulator technology
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Prediction of breast cancer risk based on profiling with common genetic variants
No full text© 2015 © The Author 2015. Published by Oxford University Press.Background: Data for multiple common susceptibility alleles for breast cancer may be combined to identify women at different levels of breast cancer risk. Such stratification could guide preve
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