385 research outputs found

    Design integration and noise studies for jet STOL aircraft. Task 7A: Augmentor wing cruise blowing valveless system. Volume 1: System design and test integration

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    Exploratory design studies conducted to establish the configuration of an augmentor wing vruise blowing (valveless) system in a 150-passenger STOL airplane were reported in NASA CR-114570. Those studies have been updated to incorporate the results of static rig, flow duct, and wind tunnel tests. Minor adjustments in duct flow velocity, flap length, and blowing nozzle geometry were incorporated to provide airplane characteristics that minimize takeoff gross weight and achieve sideline noise objectives for an advanced commercial STOL airplane

    Tree Stock, Structure and Use of Common Woody Species of a Town Neighboring Forest Reserve in Tanzania: Implication for Managing Carbon Accumulation

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    Town neighboring forests in the tropics suffer high human pressure owing to unregulated harvest to supply domestic energy and equipment. Although this causes considerable source of income among communities, it poses significant deforestation, thus, jeopardizing carbon accumulation potentials of most of the forests. This study therefore assessed the stock, structure and use of common woody species in a town neighboring forest reserve to elucidate the reserve’s carbon accumulation potential amid pressures from surrounding communities. It was found out that the structure of the forest had been altered following unregulated tree harvest. There were selective harvesting and removal of valued timber trees, and key species that otherwise are responsible in regulating the ecosystem functioning of the reserve. It was apparent that the unregulated harvest is likely to jeopardize the ecosystem functioning and carbon accumulation potential of the reserve. Thus, to manage the reserve sustainably, awareness education on forest biodiversity conservation among surrounding local communities is recommended. We also recommend exploration of the reserve for ecotourism potentials. This might stimulate ecotourism activities in the area and provide an alternative source of income among the local population. This would add value and sense of ownership and stimulate self-mobilization for protection of the reserve

    The Politics of Service Delivery Reform

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    This article identifies the leaders, the supporters and the resisters of public service reform. It adopts a principal–agent framework, comparing reality with an ‘ideal’ situation in which citizens are the principals over political policy-makers as their agents, and policy-makers are the principals over public service officials as their agents. Reform in most developing countries is complicated by an additional set of external actors — international financial institutions and donors. In practice, international agencies and core government officials usually act as the ‘principals’ in the determination of reforms. The analysis identifies the interests involved in reform, indicating how the balance between them is affected by institutional and sectoral factors. Organizational reforms, particularly in the social sectors, present greater difficulties than first generation economic policy reforms

    JWST/MIRI coronagraphic performances as measured on-sky

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    Characterization of directly imaged exoplanets is one of the most eagerly anticipated science functions of the James Webb Space Telescope. MIRI, the mid-IR instrument has the capability to provide unique spatially resolved photometric data points in a spectral range never achieved so far for such objects. We aim to present the very first on-sky contrast measurements of the MIRI's coronagraphs. In addition to a classical Lyot coronagraph at the longest wavelength, this observing mode implements the concept of the four quadrant phase mask for the very first time in a space telescope. We observed single stars together with a series of reference stars to measure raw contrasts as they are delivered on the detector, as well as reference subtracted contrasts. MIRI's coronagraphs achieve raw contrasts greater than 10310^3 at the smallest angular separations (within 1â€Čâ€Č1'') and about 10510^5 further out (beyond 5∌6â€Čâ€Č5\sim6''). Subtracting the residual diffracted light left unattenuated by the coronagraph has the potential to bring the final contrast down to the background and detector limited noise floor at most angular separations (a few times 10410^4 at less than 1â€Čâ€Č1''). MIRI coronagraphs behave as expected from simulations. In particular the raw contrasts for all four coronagraphs are fully consistent with the diffractive model. Contrasts obtained with subtracting reference stars also meet expectations and are fully demonstrated for two four quadrant phase masks (F1065C and F1140C). The worst contrast, measured at F1550C, is very likely due to a variation of the phase aberrations at the primary mirror during the observations, and not an issue of the coronagraph itself. We did not perform reference star subtraction with the Lyot mask at F2300C, but we anticipate that it would bring the contrast down to the noise floor.Comment: submitted to A&

    Bringing emotion to work: Emotional intelligence, resistance, and the reinvention of character

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    This article centrally examines the sociological significance of emotional intelligence (EI) as a nascent managerial discourse. Through developing a three-way reading of the writers Richard Sennett, Daniel Goleman, and George Ritzer, it is contended that EI can be understood to signal ‘new rules’ for work involving demands for workers to develop moral character better attuned to the dynamics of the flexible workplace - character that is more ‘intelligent’, adaptive, and reflexive. Furthermore, it is argued that while EI appears in some important respects to open the scope for worker discretion, it might also signal diminished scope for worker resistance. However, ultimately, the case of EI is used to problematise recent discussions of worker resistance - to suggest the possibility of ‘resistant’ worker agency exercised through collusion with, as well as transgression of, corporate norms and practices
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