Symmetric Extensions of Dihedral Quandles and Triple Points of Non-orientable Surfaces

Quandles with involutions that satisfy certain conditions, called good involutions, can be used to color non-orientable surface-knots. We use subgroups of signed permutation matrices to construct non-trivial good involutions on extensions of odd order dihedral quandles. For the smallest example of order 6 that is an extension of the three-element dihedral quandle, various symmetric quandle homology groups are computed, and applications to the minimal triple point number of surface-knots are given.Comment: Error in quandle table repaired, and spurious figures remove

Self-Similar Collapse of Scalar Field in Higher Dimensions

This paper constructs continuously self-similar solution of a spherically symmetric gravitational collapse of a scalar field in n dimensions. The qualitative behavior of these solutions is explained, and closed-form answers are provided where possible. Equivalence of scalar field couplings is used to show a way to generalize minimally coupled scalar field solutions to the model with general coupling.Comment: RevTex 3.1, 15 pages, 3 figures; references adde

Corporate Social Responsibility: Considerations for Sport Management in the Age of Neoliberalism

International Journal of Exercise Science 10(6): 900-914, 2017. For financial reasons, in efforts to maintain legitimacy, and in response to social pressures, sport organizations increasingly engage with corporate social responsibility (CSR). However, with the rise of global neoliberalism, the logic of CSR can be problematic. In this essay, we provide a brief overview, critique, and reconstruction of CSR in the sport industry. Specifically, we call into question three popularized forms of CSR: (1) diversity, inclusion, and diversity management, (2) environmental responsibility, and (3) health and physical activity-based initiatives. In a neoliberal context, CSR in sport provides, at best, a limited response to social issues. At their worst, CSR initiatives may be socially irresponsible programs that further engender inequalities and inequities while a neoliberal logic serves to rationalize and augment sport organizations’ place(s) in society. We discuss these issues and challenge the field of sport management to further consider how we may demonstrate a more legitimate social concern in the 21st centur

On critical behaviour in gravitational collapse

We give an approach to studying the critical behaviour that has been observed in numerical studies of gravitational collapse. These studies suggest, among other things, that black holes initially form with infinitesimal mass. We show generally how a black hole mass formula can be extracted from a transcendental equation. Using our approach, we give an explicit one parameter set of metrics that are asymptotically flat and describe the collapse of apriori unspecified but physical matter fields. The black hole mass formula obtained from this metric exhibits a mass gap - that is, at the onset of black hole formation, the mass is finite and non-zero.Comment: 11 pages, RevTex, 2 figures (available from VH

Surface gravity in dynamical spherically symmetric spacetimes

A definition of surface gravity at the apparent horizon of dynamical spherically symmetric spacetimes is proposed. It is based on a unique foliation by ingoing null hypersurfaces. The function parametrizing the hypersurfaces can be interpreted as the phase of a light wave uniformly emitted by some far-away static observer. The definition gives back the accepted value of surface gravity in the static case by virtue of its nonlocal character. Although the definition is motivated by the behavior of outgoing null rays, it turns out that there is a simple connection between the generalized surface gravity, the acceleration of any radially moving observer, and the observed frequency change of the infalling light signal. In particular, this gives a practical and simple method of how any geodesic observer can determine surface gravity by measuring only the redshift of the infalling light wave. The surface gravity can be expressed as an integral of matter field quantities along an ingoing null line, which shows that it is a continuous function along the apparent horizon. A formula for the area change of the apparent horizon is presented, and the possibility of thermodynamical interpretation is discussed. Finally, concrete expressions of surface gravity are given for a number of four-dimensional and two-dimensional dynamical black hole solutions.Comment: 35 pages, revtex, 3 figures included using eps

Comparação dos modelos digitais de elevação gerados com dados SRTM e cartas IBGE na escala 1:250.000 na região da Bacia do Camanducaia no Estado de São Paulo.

O estudo comparou os MDEs, os mapas de declividade e os mapas hipsométricos produzidos pela SRTM com aqueles gerados pelas cartas do IBGE. A área estudada integra a bacia do Camanducaia, que limita-se como Estado de São Paulo a leste e Jaguariúna a oeste, abrangendo Holambra, Jaguariúna, Santo Antônio de Posse, Pedreira, Amparo, Serra Negra, Monte Alegre do Sul, Socorro, Pinhalzinho e Pedra Bela

Uso de imagens de radar na estimativa da temperatura do ar.

O trabalho propõe um método para a estimativa da temperatura do ar baseado em um MDE construído a partir de dados do radar SRTM. Segundo os autores a estimativa de temperaturas medidas mensais e anuais do ar a partir de coordenadas geográficas e altitude foi pesquisada por diversos autores. Apesar do grande número de trabalhos, muitos estados brasileiros carecem de informações climatológicas de temperatura do ar, que poderiam ser geradas a partir de equações de estimativas associadas a modelos digitais de elevação (MDE)

Self-Similar Collapse of Conformally Coupled Scalar Fields

A massless scalar field minimally coupled to the gravitational field in a simplified spherical symmetry is discussed. It is shown that, in this case, the solution found by Roberts, describing a scalar field collapse, is in fact the most general one. Taking that solution as departure point, a study of the gravitational collapse for the self-similar conformal case is presented.Comment: 9 pages, accepted for publication, Classical and Quantum Gravity. Available at http://dft.if.uerj.br/preprint/e-17.tex or at ftp://dft.if.uerj.br/preprint/e-17.tex . Figures can be obtained on request at [email protected]

Educação ambiental e agroecossistemas sustentáveis em WebGIS.

Este trabalho mostra o uso tecnologias de sensoriamento remoto para disponibilizar informações georreferenciadas pela Internet pelo instrumental WebGIS. Dessa forma, objetiva-se contribuir na disseminação dos dados oriundos de sistemas agrícolas sustentáveis e na educação ambiental agrícola

Espacialização da pecuária de corte sul-mato-grossense.

A economia do Estado de Mato Grosso do Sul baseia-se principalmente na agricultura e pecuária, e o estado é subdivido em quatro mesorregiões: Centro-Norte, Pantanal, Sudoeste e Leste. Para espacializar a produção da pecuária bovina sul-mato-grossense, foram usados dados censitários e geocódigos municipais do IBGE e procedimentos do sistema de informação geográfica (SIG). As mesorregiões Leste e Sudoeste comportam o maior número de cabeças, da ordem de seis milhões. A mesorregião do Pantanal possui imensas áreas alagadas e favorece a exploração extensiva, e a mesorregião Centro-Norte, localizada mais próxima aos grandes mercados consumidores, têm cerca de quatro milhões de cabeças. A taxa geométrica de crescimento (TGC) do rebanho bovino de 2006 a 2011 apresenta padrão irregular, com variação de -6,86 a +7,31, -5,60 a +13,33, -2,65 a +6,65 e -5,15 a +2,45 para as regiões Pantanal, Centro-Norte, Sudoeste e Leste, respectivamente. Em termos nacionais, as projeções da TGC (2007 a 2023) para consumo e exportação são da ordem de 30% e 22,4%, respectivamente, enquanto a TGC para produção nesse mesmo período é da ordem de 18,4%. Esses números representam menos oferta interna e potencial aquecimento dos preços domésticos, contribuindo, assim, para um possível aumento da taxa de inflação no período analisado