Using gamma regression for photometric redshifts of survey galaxies

Machine learning techniques offer a plethora of opportunities in tackling big data within the astronomical community. We present the set of Generalized Linear Models as a fast alternative for determining photometric redshifts of galaxies, a set of tools not commonly applied within astronomy, despite being widely used in other professions. With this technique, we achieve catastrophic outlier rates of the order of ~1%, that can be achieved in a matter of seconds on large datasets of size ~1,000,000. To make these techniques easily accessible to the astronomical community, we developed a set of libraries and tools that are publicly available.Comment: Refereed Proceeding of "The Universe of Digital Sky Surveys" conference held at the INAF - Observatory of Capodimonte, Naples, on 25th-28th November 2014, to be published in the Astrophysics and Space Science Proceedings, edited by Longo, Napolitano, Marconi, Paolillo, Iodice, 6 pages, and 1 figur

Coeficientes técnicos e custos agregados na cadeia produtiva do frango no oeste catarinense.

bitstream/item/58224/1/doc121.pdfProjeto n. 04.06.32.000-02

Constructal alkaline membrane fuel cell (AMFC) design

This paper introduces a structured procedure to optimize the internal structure (relative sizes, spacing) and external shape (aspect ratios) of a single alkaline membrane fuel cell so that net power is maximized. The optimization of flow geometry is conducted for the smallest (elemental) level of a fuel cell stack, i.e., the single alkaline membrane fuel cell, which is modeled as a unidirectional flow system. The polarization curve, total and net power, and efficiency are obtained as functions of temperature, pressure, electrolyte solution concentration (KOH), geometry and operating parameters. The optimization is subjected to fixed total volume. There are two levels of optimization: (i) the internal structure, which basically accounts for the relative thicknesses of two reaction and diffusion layers and the membrane space, and (ii) the external shape, which accounts for the external aspect ratios of a square section plate that contains all single alkaline membrane fuel cell components. The available volume is distributed optimally through the system so that the net power is maximized. Temperature and pressure gradients play important roles, especially as the fuel and oxidant flow paths increase. The optimized internal structure and external shape are a result of an optimal balance between electrical power output and pumping power required to supply fuel and oxidant to the fuel cell through the gas channels. In the process, a third level of optimization was found with respect to the KOH concentration in the electrolyte solution that leads to a 3-way maximized net power output. The numerical results show that the maxima found are sharp, since a variation of up to 600% in net power was observed within the tested range of AMFC external aspect ratios, what emphasizes the importance of finding the optimal AMFC parameters, no matter how complex the actual design might be. It is also shown that the three times maximized net power increases monotonically with total volume raised to the power 0.7 (~3/4), similarly to metabolic rate and mass in animal design. Due to the fact that precision and low computational time are combined, it is expected that the model could be used as an important tool for AMFC design, control and optimization at the fuel cell stack level

Constructal alkaline membrane fuel cell (AMFC) design

This paper introduces a structured procedure to optimize the internal structure (relative sizes, spacing) and external shape (aspect ratios) of a single alkaline membrane fuel cell so that net power is maximized. The optimization of flow geometry is conducted for the smallest (elemental) level of a fuel cell stack, i.e., the single alkaline membrane fuel cell, which is modeled as a unidirectional flow system. The polarization curve, total and net power, and efficiency are obtained as functions of temperature, pressure, electrolyte solution concentration (KOH), geometry and operating parameters. The optimization is subjected to fixed total volume. There are two levels of optimization: (i) the internal structure, which basically accounts for the relative thicknesses of two reaction and diffusion layers and the membrane space, and (ii) the external shape, which accounts for the external aspect ratios of a square section plate that contains all single alkaline membrane fuel cell components. The available volume is distributed optimally through the system so that the net power is maximized. Temperature and pressure gradients play important roles, especially as the fuel and oxidant flow paths increase. The optimized internal structure and external shape are a result of an optimal balance between electrical power output and pumping power required to supply fuel and oxidant to the fuel cell through the gas channels. In the process, a third level of optimization was found with respect to the KOH concentration in the electrolyte solution that leads to a 3-way maximized net power output. The numerical results show that the maxima found are sharp, since a variation of up to 600% in net power was observed within the tested range of AMFC external aspect ratios, what emphasizes the importance of finding the optimal AMFC parameters, no matter how complex the actual design might be. It is also shown that the three times maximized net power increases monotonically with total volume raised to the power 0.7 (~3/4), similarly to metabolic rate and mass in animal design. Due to the fact that precision and low computational time are combined, it is expected that the model could be used as an important tool for AMFC design, control and optimization at the fuel cell stack level

The overlooked potential of Generalized Linear Models in astronomy-II: Gamma regression and photometric redshifts

Machine learning techniques offer a precious tool box for use within astronomy to solve problems involving so-called big data. They provide a means to make accurate predictions about a particular system without prior knowledge of the underlying physical processes of the data. In this article, and the companion papers of this series, we present the set of Generalized Linear Models (GLMs) as a fast alternative method for tackling general astronomical problems, including the ones related to the machine learning paradigm. To demonstrate the applicability of GLMs to inherently positive and continuous physical observables, we explore their use in estimating the photometric redshifts of galaxies from their multi-wavelength photometry. Using the gamma family with a log link function we predict redshifts from the PHoto-z Accuracy Testing simulated catalogue and a subset of the Sloan Digital Sky Survey from Data Release 10. We obtain fits that result in catastrophic outlier rates as low as ~1% for simulated and ~2% for real data. Moreover, we can easily obtain such levels of precision within a matter of seconds on a normal desktop computer and with training sets that contain merely tho nds of galaxies. Our software is made publicly available as a user-friendly package developed in Python, R and via an interactive web application. This software allows users to apply a set of GLMs to their own photometric catalogues and generates publication quality plots with minimum effort. By facilitating their ease of use to the astronomical community, this paper series aims to make GLMs widely known and to encourage their implementation in future large-scale projects, such as the Large Synoptic Survey Telescope

Efeito de bioestimulantes sobre a concentração de nutrientes nas raízes em mudas de videira Thompson Seedless.

A cultura da videira reveste-se de especial importância econômica e social no Submédio do Vale do São Francisco. A cultivar Thompson Seedless pode ser considerada uma das mais importantes uvas sem sementes cultivadas na região. Suas bagas são pequenas, exigindo a aplicação de doses elevadas de ácido giberélico isolado ou associado a outros bioestimulantes para crescimento da baga e alongamento do cacho. O objetivo deste trabalho foi avaliar o efeito de bioestimulantes na concentração de nutrientes nas raízes em mudas de videira ?Thompson Seedless?. Foi realizado um experimento em casa de vegetação em Petrolina-PE. Foram avaliados quatro porta-enxertos ('SO4', 'Paulsen 1103', 'IAC 572' e 'Harmony'), sete produtos comerciais (Soilplex Root®, Fert Actyl GZ®, Rutter AA®, Acadian®, Codamin Radicular®, Aminoagro Raiz® e Bioradicant®) e uma testemunha. A cultivar enxertada foi Thompson Seedless. O ensaio constituiu um fatorial de 4x8 (quatro porta-enxertos, sete bioestimulantes e uma testemunha), sendo disposto em blocos ao acaso, com cinco repetições. O experimento em casa de vegetação foi conduzido por um período de 120 dias. Após a colheita, as raízes foram separadas do solo, lavadas em água desmineralizada e submetidas a secagem e moagem, sendo enviadas para análise química de macro e micronutrientes. Codamin Radicular® proporcionou aumento das concentrações de N, P e Mn; Soil Plex Root® proporcionou maiores concentrações de K e Bioradicant® maiores concentrações de N e B nas raízes de mudas de videira ?Thompson Seedless?

Tipos nomenclaturais do Herbário IAN da Embrapa Amazônia Oriental: Vochysiaceae A.ST.HIL.

Tipos nomenclaturais são amostras botânicas utilizadas para descrever, pela primeira vez, um táxon para a ciência; sendo dessa forma, uma documentação fundamental para a Taxonomia. O Herbário IAN da Embrapa Amazônia Oriental, com o acervo de 192.500 exemplares, dispõe, atualmente de aproximadamente 2.500 tipos nomenclaturais; esse número vêm aumentando à medida que as famílias são analisadas. O presente trabalho refere-se a organização, classificação e divulgação dos tipos de Vochysiaceae depositados nesse Herbário. Essa família possui importância econômica, visto que apresenta espécies utilizadas na fabricação de móveis, barcos e cercas, além das sementes que são usadas na fabricação de sabões e velas. Os exemplares de Vochysiaceae foram analisados, e para cada táxon, foi localizada a obra princeps, através de consulta a sites especializados, busca em bibliotecas, e COMUT. De posse das informações contidas na obra princeps, os tipos foram classificados segundo o Código Internacional de Nomenclatura para algas, fungos e plantas. Foram localizados 31 exemplares tipo de Vochysiaceae distribuídos em três gêneros, 24 espécies, e três variedades. Esses resultados são apresentados em tabela contendo nome do táxon, registro no IAN, coletor e número e categoria. Este trabalho, além de aumentar o número de tipos no acervo do IAN, otimizará a localização dos mesmos durante as revisões taxonômicas