23,780 research outputs found
On central tendency and dispersion measures for intervals and hypercubes
The uncertainty or the variability of the data may be treated by considering,
rather than a single value for each data, the interval of values in which it
may fall. This paper studies the derivation of basic description statistics for
interval-valued datasets. We propose a geometrical approach in the
determination of summary statistics (central tendency and dispersion measures)
for interval-valued variables
Anthropometric data collection of Portuguese children using 3D body scanning: considerations about the scanning booth
This paper presents some considerations regarding the scanning booth used in an anthropometric study done with a 3D body scanning technology. The data collected is part of a Ph.D. study conducted in Textile Engineering at University of Minho in Portugal, which aims to develop clothing for overweight and obese Portuguese children aged 2-11 years, of both genders. The challenges faced during data collection are described, and modifications of the scanning booth are proposed. It is possible to conclude that the importance of the scanning booth is key to an efficient anthropometric data collection, including the growth of this technology in the garment industry, Universities Research Institutes involved with anthropometric studies.info:eu-repo/semantics/publishedVersio
Improving the Knowledge on Seismogenic Sources in the Lower Tagus Valley for Seismic Hazard Purposes
The Lower Tagus Valley, that includes the metropolitan area of Lisbon, has been struck by several earthquakes which produced significant material damage and loss of lives. Their exact location remains unknown. Our goal is to shed some light into the seismogenic sources in the area using seismic reflection and geological data. In areas with no seismic coverage, potential-field data interpretation was carried out. Seismicity was overlaid to the potential seismogenic structures and high-resolution data was acquired in order to confirm which structures have been active into the Quaternary. Three major fault-zones affecting the Neogene were identified: V. F. Xira, Samora-Alcochete and Pinhal Novo. For the first fault, strong evidences suggest it is active. The other two fault-zones and other structures previously unknown can be correlated with several epicentres. Empirical relationships between maximum moment magnitude and fault area indicate that MW > 6.5 earthquakes can be expected for the larger structures
Comportamento produtivo do girassol na região de Campinas-SP.
O trabalho teve como objetivo avaliar o desempenho produtivo de genótipos comerciais de girassol na região de Campinas-SP. Foram testados quatro cultivares comerciais de girassol (Morgan 734, Agrobel 960, Helio 358 e Embrapa 122) em quatro safras de cultivo (safra 2007/08, safrinha 2008, safra 2008/09 e safrinha 2009), sob delineamento experimental de blocos ao acaso, em esquema fatorial 4 x 4, com quatro repetições. As parcelas experimentais constituíram-se de quatro linhas de 6,0 m, espaçadas 0,8 m entre si e 0,3 m entre plantas, sendo avaliado o rendimento final de aquênios (em kg ha-1) pela análise de variâncias e teste Tukey de comparação de médias. Houve efeito altamente significativo para o rendimento de aquênios, apenas para o efeito isolado de genótipos e safras de cultivo, sem resultados positivos para a interação entre fatores. O rendimento médio foi de 1997 kg ha-1, sendo os maiores valores observados nos híbridos Morgan 734 (2184 kg ha-1) e Agrobel 960 (2125 kg ha-1), que não diferirem entre si e nem da variedade (população de polinização aberta) Embrapa122 (2018 kg ha-1). Os períodos de safra foram os mais produtivos, entretanto, as safrinhas, mesmo que com rendimentos inferiores, ainda foram satisfatórias, com média de 1308 kg ha-1. Conclui-se que, na região de Campinas-SP, o cultivo dos genótipos de girassol Morgan 734, Agrobel 960, Helio 358 e Embrapa 122, é viável, sob o ponto de vista produtivo; sendo os maiores rendimentos observados durante o período de safra, cuja semeadura ocorre entre os meses de outubro e dezembro
Spectral statistics in chaotic systems with a point interaction
We consider quantum systems with a chaotic classical limit that are perturbed
by a point-like scatterer. The spectral form factor K(tau) for these systems is
evaluated semiclassically in terms of periodic and diffractive orbits. It is
shown for order tau^2 and tau^3 that off-diagonal contributions to the form
factor which involve diffractive orbits cancel exactly the diagonal
contributions from diffractive orbits, implying that the perturbation by the
scatterer does not change the spectral statistic. We further show that
parametric spectral statistics for these systems are universal for small
changes of the strength of the scatterer.Comment: LaTeX, 21 pages, 7 figures, small corrections, new references adde
Random attractors for degenerate stochastic partial differential equations
We prove the existence of random attractors for a large class of degenerate
stochastic partial differential equations (SPDE) perturbed by joint additive
Wiener noise and real, linear multiplicative Brownian noise, assuming only the
standard assumptions of the variational approach to SPDE with compact
embeddings in the associated Gelfand triple. This allows spatially much rougher
noise than in known results. The approach is based on a construction of
strictly stationary solutions to related strongly monotone SPDE. Applications
include stochastic generalized porous media equations, stochastic generalized
degenerate p-Laplace equations and stochastic reaction diffusion equations. For
perturbed, degenerate p-Laplace equations we prove that the deterministic,
infinite dimensional attractor collapses to a single random point if enough
noise is added.Comment: 34 pages; The final publication is available at
http://link.springer.com/article/10.1007%2Fs10884-013-9294-
Tumor de Células Germinativas Primário da Próstata – descrição de um caso raro
info:eu-repo/semantics/publishedVersio
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