1,658 research outputs found
Rede de cooperação no êxito de iniciativas voltadas para a utilização de composto orgânico na produção de hortaliças por pequenos agricultores em Camaçari-Ba.
Este trabalho apresenta resultados da interação da pesquisa e da extensão na avaliação do efeito de composto orgânico no beneficiamento de solos agrícolas, instrumentalização de agricultores a pratica da agricultura orgânica e a valorização de produtos orgânicos. O trabalho foi desenvolvido em sistema de rede de cooperação com participação de instituições publicas, privadas, desenvolvimento de pesquisa de mestrado, alunos de graduação e pequenos agricultores. A rede busca a preservação do patrimônio ambiental através do reaproveitamento de lixo orgânico e o beneficiamento de solos com composto orgânico. A pesquisa de mestrado avaliou efeitos do composto na produção de hortaliças empregando-se indicadores de sustentabilidade. A disciplina da graduação desenvolve atividades praticas com cunho socioambiental. O experimento cientifico foi realizado na propriedade dos agricultores que acompanharam o efeito do composto proveniente de resíduos orgânicos no incremento da produção de hortaliças. Os resultados alcançados com este trabalho mostram a importância do sistema de rede de cooperação na integração da pesquisa e da extensão
Morphological and microstructural characterization of laser-glazedplasma-sprayed thermal barrier coatings
Laser glazing has been revealing a high potential for the improvement of plasma-sprayed (PS) thermal barrier coatings (TBCs) by
reducing surface roughness, eliminating open porosity on the surface and generating a controlled segmented crack network, although the
relationship of the processing parameters with the resultant properties has not yet been completely established. In this investigation, TBCs
consisting of atmospheric plasma-sprayed (APS) ZrO2–8wt.%Y2O3 were subjected to a CO2 continuous wave laser-glazing process in
order to seal its surface porosity, generating an external dense layer. For that purpose, different amounts of radiation resulting from different
scanning speeds were applied to the specimens as well as different track overlapping. Results have shown a significant decrease of the
surface roughness after the laser treatment. All specimens presented a fully dense and porous free external layer with a polyfaceted
columnar microstructure highly adherent to the plasma-sprayed coating. Controlled surface crack networks, extremely dependent on the
laser scanning speed and track overlapping, were achieved for each set of processing parameters. The cracks were found to have a
tendency to be oriented in two perpendicular directions, one in the direction of the laser-beam travel direction, the other perpendicular to it.
Moreover, the cracks parallel to the beam travel direction are found to be on the overlapping zone, coinciding with the edge of the
subsequent track. The cracks are perpendicular to the surface along the densified layer and tend to branch and deviate from the vertical
direction below it, within the porous PS coating. XRD results revealed mainly tV nontransformable tetragonal zirconia with a small
percentage of residual monoclinic zirconia for the as-sprayed coating. All glazed coatings presented only tV nontransformable tetragonal
zirconia with some variations on preferable crystal orientation. Grain sizes varied from 26 to 52 nm, increasing with an increase of laserirradiated
energy; microstrain behaved inversely.Fundação para a Ciência e a Tecnologia (FCT) - Project POCTI/CTM/44590/2002.União Europeia (UE). Fundo Europeu de Desenvolvimento Regional (FEDER)
Measuring CMB Polarization with BOOMERANG
BOOMERANG is a balloon-borne telescope designed for long duration (LDB)
flights around Antarctica. The second LDB Flight of BOOMERANG took place in
January 2003. The primary goal of this flight was to measure the polarization
of the CMB. The receiver uses polarization sensitive bolometers at 145 GHz.
Polarizing grids provide polarization sensitivity at 245 and 345 GHz. We
describe the BOOMERANG telescope noting changes made for 2003 LDB flight, and
discuss some of the issues involved in the measurement of polarization with
bolometers. Lastly, we report on the 2003 flight and provide an estimate of the
expected results.Comment: 12 pages, 8 figures, To be published in the proceedings of "The
Cosmic Microwave Background and its Polarization", New Astronomy Reviews,
(eds. S. Hanany and K.A. Olive). Fixed typos, and reformatted citation
Convergence of the critical attractor of dissipative maps: Log-periodic oscillations, fractality and nonextensivity
For a family of logistic-like maps, we investigate the rate of convergence to
the critical attractor when an ensemble of initial conditions is uniformly
spread over the entire phase space. We found that the phase space volume
occupied by the ensemble W(t) depicts a power-law decay with log-periodic
oscillations reflecting the multifractal character of the critical attractor.
We explore the parametric dependence of the power-law exponent and the
amplitude of the log-periodic oscillations with the attractor's fractal
dimension governed by the inflexion of the map near its extremal point.
Further, we investigate the temporal evolution of W(t) for the circle map whose
critical attractor is dense. In this case, we found W(t) to exhibit a rich
pattern with a slow logarithmic decay of the lower bounds. These results are
discussed in the context of nonextensive Tsallis entropies.Comment: 8 pages and 8 fig
Suppressing CMB Quadrupole with a Bounce from Contracting Phase to Inflation
Recent released WMAP data show a low value of quadrupole in the CMB
temperature fluctuations, which confirms the early observations by COBE. In
this paper, a scenario, in which a contracting phase is followed by an
inflationary phase, is constructed. We calculate the perturbation spectrum and
show that this scenario can provide a reasonable explanation for lower CMB
anisotropies on large angular scales.Comment: 5 pages, 3 figure
Cosmic microwave background anisotropies in multi-connected flat spaces
This article investigates the signature of the seventeen multi-connected flat
spaces in cosmic microwave background (CMB) maps. For each such space it
recalls a fundamental domain and a set of generating matrices, and then goes on
to find an orthonormal basis for the set of eigenmodes of the Laplace operator
on that space. The basis eigenmodes are expressed as linear combinations of
eigenmodes of the simply connected Euclidean space. A preceding work, which
provides a general method for implementing multi-connected topologies in
standard CMB codes, is then applied to simulate CMB maps and angular power
spectra for each space. Unlike in the 3-torus, the results in most
multi-connected flat spaces depend on the location of the observer. This effect
is discussed in detail. In particular, it is shown that the correlated circles
on a CMB map are generically not back-to-back, so that negative search of
back-to-back circles in the WMAP data does not exclude a vast majority of flat
or nearly flat topologies.Comment: 33 pages, 19 figures, 1 table. Submitted to PR
Non-western contexts: the invisible half
Like many other disciplines within the broad area of social sciences (e.g., anthropology, gender studies, psychology, sociology, etc.), consumer research is also highly navigated by scholars from Western countries. This, however, does not mean, by any means, that consumer research is devoted to studying Western contexts only. As evident from the ever-increasing number of regional conferences (e.g., Asia-Pacific and Latin American conferences of the Association for Consumer Research) and non-Western students' enrolment in doctoral programs at Western universities, there are many more researchers (from non-Western countries) who are entering the field and enriching it by their colourful contributions. Yet, given the low number of publications on consumer research in non-Western contexts, it seems that our current knowledge in these societies has a long way to go to flourish. More specifically, and in the domain of consumption culture research, this gap is even further widened by the fact that the culture of consumption in such contexts is largely interpreted with reference to the 'grand narratives' of Western scholars (e.g., Foucault, Mafessoli, Bourdieu, Deleuze, Baudrillard, Nietzsche, Durkheim, Derrida, etc.). Therefore, from an ontological perspective, it seems that our existing knowledge about non-Western societies lies heavily on the 'theoretical structures' that are 'constructed' by Western philosophy as a set of ideas, beliefs, and practices (Said, 1978). As Belk (1995) reminds us, consumption culture always existed in all human societies. What makes contemporary societies different from that of our predecessors' is not the fact that consumption culture did not exist in those societies, but that consumption culture has become a prevailing feature in modern society (Slater, 1997; Lury, 1996; Fırat and Venkatesh, 1995; McCracken, 1988). Therefore, the nature and dynamics of consumption culture in each society should be studied not only against the sociocultural, historical, and economic background of a given context (Western or non-Western) but also with reference to the philosophical and epistemological viewpoints that analyse and interpret cultural practices of that society from within that culture. Addressing such issues, this paper discusses some of the key reasons for lack of theory development in the field from non-western contexts. The paper invites scholars in non-Western contexts to introduce the less articulated, and sometime hidden, body of knowledge from their own contexts into the field of marketing in general and consumer research in particular
Large-scale power in the CMB and new physics: An analysis using Bayesian model comparison
Published versio
Cosmological parameters from SDSS and WMAP
We measure cosmological parameters using the three-dimensional power spectrum
P(k) from over 200,000 galaxies in the Sloan Digital Sky Survey (SDSS) in
combination with WMAP and other data. Our results are consistent with a
``vanilla'' flat adiabatic Lambda-CDM model without tilt (n=1), running tilt,
tensor modes or massive neutrinos. Adding SDSS information more than halves the
WMAP-only error bars on some parameters, tightening 1 sigma constraints on the
Hubble parameter from h~0.74+0.18-0.07 to h~0.70+0.04-0.03, on the matter
density from Omega_m~0.25+/-0.10 to Omega_m~0.30+/-0.04 (1 sigma) and on
neutrino masses from <11 eV to <0.6 eV (95%). SDSS helps even more when
dropping prior assumptions about curvature, neutrinos, tensor modes and the
equation of state. Our results are in substantial agreement with the joint
analysis of WMAP and the 2dF Galaxy Redshift Survey, which is an impressive
consistency check with independent redshift survey data and analysis
techniques. In this paper, we place particular emphasis on clarifying the
physical origin of the constraints, i.e., what we do and do not know when using
different data sets and prior assumptions. For instance, dropping the
assumption that space is perfectly flat, the WMAP-only constraint on the
measured age of the Universe tightens from t0~16.3+2.3-1.8 Gyr to
t0~14.1+1.0-0.9 Gyr by adding SDSS and SN Ia data. Including tensors, running
tilt, neutrino mass and equation of state in the list of free parameters, many
constraints are still quite weak, but future cosmological measurements from
SDSS and other sources should allow these to be substantially tightened.Comment: Minor revisions to match accepted PRD version. SDSS data and ppt
figures available at http://www.hep.upenn.edu/~max/sdsspars.htm
- …
