Studies of the photoionization cross sections of CH_4

We present cross sections and asymmetry parameters for photoionization of the 1t_2 orbital of CH_4 using static‐exchange continuum orbitals of CH^+_4 to represent the photoelectron wave function. The calculations are done in the fixed‐nuclei approximation at a single internuclear geometry. To approximate the near‐threshold behavior of these cross sections, we assumed that the photoelectron spectrum is a composite of three electronic bands associated with the Jahn–Teller components of the distorted ion. The resulting cross sections reproduce the sharp rise seen at threshold in the experimental data and are in good agreement with experiment at higher energy. The agreement between the calculated and measured photoelectron asymmetry parameters is, however, less satisfactory

Mecanismo de desenvolvimento limpo (MDL): funcionamento, pontos críticos e possibilidades para alguns sistemas agrícolas no Brasil.

Funcionamento do MDL; Financiamento do Projeto MDL; Monitoramento, verificação e certificação de ERs.bitstream/CNPS/11208/1/doc412002.pd

Monitoring and assessment of sustainable land management: overview of issues.

Defining sustainable land management. A reference frame for the monitoring and assessment of sustainable land management. Advanced scientific methods for the monitoring and assessment of sustainable land management. Key natural resources underpinning sustainable land management. Water. Phosphorus. Soil organic carbon. Connections of monitoring and assessment of sustainable land management to climate change and biodiversity conventions.Proceedings of the UNCCD First Scientific Conference, 22-24 September 2009, during the UNCCD Ninth Conference of Parties, Buenos Aires, Argentina

Fracionamento físico do solo por densidade e granulometria para a quantificação de compartimentos da matéria orgânica do solo: um procedimento para a estimativa pormenorizada do seqüestro de carbono pelo solo.

bitstream/item/62000/1/comtec09-2002-fracionamento.pd

Compactação do solo e crescimento de plantas: como identificar, evitar e remediar.

A compactação do solo é um fenômeno conhecido e constitui tema de crescente importância demandando muita atenção por parte de produtores rurais, agrônomos da extensão rural, profissionais de vendas e assistência de tratores e implementos agrícolas e consultores. O solo compactado vem resultando na diminuição no crescimento das raízes em profundidade, predispondo a planta à morte em curtos períodos de seca, no acúmulo de água na superfície do solo impossibilitando a respiração das raízes e favorecendo o processo de erosão hídrica do solo. Esta publicação visa auxiliar, de modo sucinto, na identificação da compactação do solo, como evitar seu surgimento e como resolver o problema quando constatado.bitstream/CNPS/11604/1/doc56_2003_compactacao_solo.pd

Darth Fader: Using wavelets to obtain accurate redshifts of spectra at very low signal-to-noise

We present the DARTH FADER algorithm, a new wavelet-based method for estimating redshifts of galaxy spectra in spectral surveys that is particularly adept in the very low SNR regime. We use a standard cross-correlation method to estimate the redshifts of galaxies, using a template set built using a PCA analysis on a set of simulated, noise-free spectra. Darth Fader employs wavelet filtering to both estimate the continuum & to extract prominent line features in each galaxy spectrum. A simple selection criterion based on the number of features present in the spectrum is then used to clean the catalogue: galaxies with fewer than six total features are removed as we are unlikely to obtain a reliable redshift estimate. Applying our wavelet-based cleaning algorithm to a simulated testing set, we successfully build a clean catalogue including extremely low signal-to-noise data (SNR=2.0), for which we are able to obtain a 5.1% catastrophic failure rate in the redshift estimates (compared with 34.5% prior to cleaning). We also show that for a catalogue with uniformly mixed SNRs between 1.0 & 20.0, with realistic pixel-dependent noise, it is possible to obtain redshifts with a catastrophic failure rate of 3.3% after cleaning (as compared to 22.7% before cleaning). Whilst we do not test this algorithm exhaustively on real data, we present a proof of concept of the applicability of this method to real data, showing that the wavelet filtering techniques perform well when applied to some typical spectra from the SDSS archive. The Darth Fader algorithm provides a robust method for extracting spectral features from very noisy spectra. The resulting clean catalogue gives an extremely low rate of catastrophic failures, even when the spectra have a very low SNR. For very large sky surveys, this technique may offer a significant boost in the number of faint galaxies with accurately determined redshifts.Comment: 22 pages, 15 figures. Accepted for publication in Astronomy & Astrophysic

A complexity approach for identifying aesthetic composite landscapes

Third European Conference, EvoMUSART 2014, Granada, Spain, April 23-25, 2014, Revised Selected Papers[Abstract] The present paper describes a series of features related to complexity which may allow to estimate the complexity of an image as a whole, of all the elements integrating it and of those which are its focus of attention. Using a neural network to create a classifier based on those features an accuracy over 85% in an aesthetic composition binary classification task is achieved. The obtained network seems to be useful for the purpose of assessing the Aesthetic Composition of landscapes. It could be used as part of a media device for facilitating the creation of images or videos with a more professional aesthetic composition.Galicia. Consellería de Innovación, Industria e Comercio; PGIDIT 10TIC105008PRPortugal. Fundação para a Ciência e a Tecnologia; PTDC/EIA-EIA/115667/200