911 resultados para Congress of Industrial Organizations (U.S.)


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Investigations were conducted during the 2003, 2004 and 2005 growing seasons in northern Greece to evaluate effects of tillage regime (mouldboard plough, chisel plough and rotary tiller), cropping sequence (continuous cotton, cotton-sugar beet rotation and continuous tobacco) and herbicide treatment on weed seedbank dynamics. Amaranthus spp. and Portulaca oleracea were the most abundant species, ranging from 76% to 89% of total weed seeds found in 0-15 and 15-30 cm soil depths during the 3 years. With the mouldboard plough, 48% and 52% of the weed seedbank was found in the 0-15 and 15-30 cm soil horizons, while approximately 60% was concentrated in the upper 15 cm soil horizon for chisel plough and rotary tillage. Mouldboard ploughing significantly buried more Echinochloa crus-galli seeds in the 15-30 cm soil horizon compared with the other tillage regimes. Total seedbank (0-30 cm) of P. oleracea was significantly reduced in cotton-sugar beet rotation compared with cotton and tobacco monocultures, while the opposite occurred for E. crus-galli. Total seed densities of most annual broad-leaved weed species (Amaranthus spp., P. oleracea, Solanum nigrum) and E. crus-galli were lower in herbicide treated than in untreated plots. The results suggest that in light textured soils, conventional tillage with herbicide use gradually reduces seed density of small seeded weed species in the top 15 cm over several years. In contrast, crop rotation with the early established sugar beet favours spring-germinating grass weed species, but also prevents establishment of summer-germinating weed species by the early developing crop canopy.

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A three degrees of freedom industrial robot is controlled by applying PID self-tuning (PID/ST) controllers. This control is considered as a corrective term to a nominal value, centrally computed from an inaccurate and/ or simplified dynamic model. An identification scheme on an assumed linear plant describing the deviation from the desired trajectory is employed in order to tune the controller coefficients and thus accomplish a behaviour prescribed through a desired pole placement. A salient feature of our approach is the decentralized nature of the controllers producing the corrective term for each joint. This opens the way to practical implementation, as recent computing requirement calculations for similar set-ups have shown in the literature. Numerical results are presented.

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We present a summary of the principal physical and optical properties of aerosol particles using the FAAM BAE-146 instrumented aircraft during ADRIEX between 27 August and 6 September 2004, augmented by sunphotometer, lidar and satellite retrievals. Observations of anthropogenic aerosol, principally from industrial sources, were concentrated over the northern Adriatic Sea and over the Po Valley close to the aerosol sources. An additional flight was also carried out over the Black Sea to compare east and west European pollution. Measurements show the single-scattering albedo of dry aerosol particles to vary considerably between 0.89 and 0.97 at a wavelength of 0.55 μm, with a campaign mean within the polluted lower free troposphere of 0.92. Although aerosol concentrations varied significantly from day to day and during individual days, the shape of the aerosol size distribution was relatively consistent through the experiment, with no detectable change observed over land and over sea. There is evidence to suggest that the pollution aerosol within the marine boundary layer was younger than that in the elevated layer. Trends in the aerosol volume distribution show consistency with multiple-site AERONET radiometric observations. The aerosol optical depths derived from aircraft measurements show a consistent bias to lower values than both the AERONET and lidar ground-based radiometric observations, differences which can be explained by local variations in the aerosol column loading and by some aircraft instrumental artefacts. Retrievals of the aerosol optical depth and fine-mode (<0.5 μm radius) fraction contribution to the optical depth using MODIS data from the Terra and Aqua satellites show a reasonable level of agreement with the AERONET and aircraft measurements.

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Mostra evidências de relação entre os atributos de qualidade de um serviço de realibilitação ambulatorial sob a percepção do cliente e os padrões do modelo internacional de acreditação de serviço de saúde.

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This paper examines the current global scene of distributional disparities within-nations. There are six main conclusions. First, about 80 per cent of the world’s population now live in regions whose median country has a Gini not far from 40. Second, as outliers are now only located among middle-income and rich countries, the ‘upwards’ side of the ‘Inverted-U’ between inequality and income per capita has evaporated (and with it the statistical support there was for the hypothesis that posits that, for whatever reason, ‘things have to get worse before they can get better’). Third, among middle-income countries Latin America and mineral-rich Southern Africa are uniquely unequal, while Eastern Europe follows a distributional path similar to the Nordic countries. Fourth, among rich countries there is a large (and growing) distributional diversity. Fifth, within a global trend of rising inequality, there are two opposite forces at work. One is ‘centrifugal’, and leads to an increased diversity in the shares appropriated by the top 10 and bottom 40 per cent. The other is ‘centripetal’, and leads to a growing uniformity in the income-share appropriated by deciles 5 to 9. Therefore, half of the world’s population (the middle and upper-middle classes) have acquired strong ‘property rights’ over half of their respective national incomes; the other half, however, is increasingly up for grabs between the very rich and the poor. And sixth, Globalisation is thus creating a distributional scenario in which what really matters is the income-share of the rich — because the rest ‘follows’ (middle classes able to defend their shares, and workers with ever more precarious jobs in ever more ‘flexible’ labour markets). Therefore, anybody attempting to understand the within-nations disparity of inequality should always be reminded of this basic distributional fact following the example of Clinton’s campaign strategist: by sticking a note on their notice-boards saying “It’s the share of the rich, stupid”.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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We point out that determination of the MNS matrix element \U-e3\ = s(13) in long-baseline nu(mu) --> nu(e) neutrino oscillation experiments suffers from large intrinsic uncertainty due to the unknown CP violating phase delta and sign of Deltam(13)(2). We propose a new strategy for accurate determination of theta(13); tune the beam energy at the oscillation maximum and do the measurement both in neutrino and antineutrino channels. We show that it automatically resolves the problem of parameter ambiguities which involves delta, theta(13), and the sign of Deltam(13)(2). (C) 2002 Elsevier B.V. B.V. All rights reserved.

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Groundwaters; and surface waters around two waste disposal areas at Rio Claro municipality, nearly in the center of São Paulo State, Brazil, were chemically analysed with the purpose of evaluating the influence on the water quality of the chemicals released without any care with the environment and using a prevention system for the containment of environmentally polluting substances.

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Laboratory time-scale experiments were conducted on limestone and dolomite gravels from the Mendip Hills area, England, with the purpose of evaluating the release of U-238 and U-234 to different aqueous solutions. The U-234/U-238 activity ratio (AR) lab data were reliable to interpret the field data. The obtained values do not indicate a reduction in the amount of dissolved U and an increase in the AR of the remaining dissolved U as commonly observed for groundwater systems close to redox boundaries. (C) 2000 Elsevier B.V. Ltd. All rights reserved.