12,822 research outputs found

    Radiant heat source, vacuum bag, provide portable bonding oven

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    Portable bonding oven is formed to any desired size or configuration to attach doublers and brackets to the surfaces of large structures. A radiant heat source is used in combination with a heat resistant transport vacuum bag and a black heat absorbing cloth

    Effect of fuel sprays on emissions

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    A research gas turbine combustor was operated under realistic conditions such that the influence of individual variables (in particular, fuel spray characteristics) on emissions could be determined. The special combustor allows independent control over drop size, fuel-air ratio, air inlet temperature, pressure, reference velocity, and residence time. Also, it lends itself to theoretical modeling and turbulent intensity measurements through use of laser velocimetry. Emission results for a range of operations are presented. A number of graphs show which show the variations of emissions levels with one variable at a time are included. In every case, the fuel is jet A, the pressure is atmospheric, and combustion is limited to a primary zone

    Two phase detonation studies conducted in 1970 Annual report, 1 Feb. 1970 - 1 Feb. 1971

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    Two phase detonation waves in liquid gas system

    Two Phase Detonation as Related to Rocket Motor Combustion Instability

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    Two phase detonations in liquid-gas system of liquid rocket moto

    Personal effectiveness training for unemployed people: where to now?

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    Unemployment remains a major social problem in Australia. Successive governments have attempted to address the problem, in part, by funding occupational skills based training programs for the unemployed. This paper reviews the general area of occupational skills/personal effectiveness training for unemployed people, and reports on outcomes for individuals attending 'typical' courses in Australia. Also reported, are outcomes for unemployed people who attended specially devised training, based on the cognitive behavioural (e.g., Beck, 1976) and learned optimism (Seligman, 1990) intervention approaches, that was aimed at improving well-being, confidence and coping abilities. Variables assessed include individual well-being (e.g., psychological distress), confidence (e.g., self-efficacy), attitude-to-work (e.g., work-commitment); training climate; and labour market outcomes such as return-to-work. More positive outcomes were identified for unemployed people attending the specially devised programs. The authors argue that training targeted at unemployed people must be based on sound theoretical principles to produce measurable long-term benefits. Future applications of personal development programs are discussed in relation to occupational skills based training and as stand-alone programs

    Subsonic sphere drag measurements at intermediate Reynolds numbers

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    Wind tunnel drag measurements on subsonic spher

    Nano and Micro indentation studies of bulk zirconia and EB PVD TBCs

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    In order to model the erosion of a material it is necessary to know the material properties of both the impacting particles as well as the target. In the case of electron beam (EB) physical vapour deposited(PVD) thermal barrier coatings (TBCs) the properties of the columns as opposed to the coating as a whole are important. This is due to the fact that discrete erosion events are on a similar scale as the size of the individual columns. Thus nano* and micro* indentation were used to determine the hardness and the Young"s modulus of the columns. However, care had to be taken to ensure that it was the hardness of the columns that was being measured and not the coating as a whole. This paper discusses the differences in the results obtained when using the two different tests and relates them to the interactions between the indent and the columns of the EB PVD TBC microstructure. It was found that individual columns had a hardness of 14 GPa measured using nano indentation, while the hardness of the coating, using micro indentation decreased from 13 to 2.4 GPa as the indentation load increased from 0.1 to 3N. This decrease in hardness was attributed to the interaction between the indenter and a number of adjacent columns and the ability of the columns to move laterally under indentation

    Resolving the electron temperature discrepancies in HII Regions and Planetary Nebulae: kappa-distributed electrons

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    The measurement of electron temperatures and metallicities in H ii regions and Planetary Nebulae (PNe) has-for several decades-presented a problem: results obtained using different techniques disagree. What it worse, they disagree consistently. There have been numerous attempts to explain these discrepancies, but none has provided a satisfactory solution to the problem. In this paper, we explore the possibility that electrons in H ii regions and PNe depart from a Maxwell-Boltzmann equilibrium energy distribution. We adopt a "kappa-distribution" for the electron energies. Such distributions are widely found in Solar System plasmas, where they can be directly measured. This simple assumption is able to explain the temperature and metallicity discrepancies in H ii regions and PNe arising from the different measurement techniques. We find that the energy distribution does not need to depart dramatically from an equilibrium distribution. From an examination of data from Hii regions and PNe it appears that kappa ~ 10 is sufficient to encompass nearly all objects. We argue that the kappa-distribution offers an important new insight into the physics of gaseous nebulae, both in the Milky Way and elsewhere, and one that promises significantly more accurate estimates of temperature and metallicity in these regions.Comment: 16 pages, 11 figures, 2 tables, published in Ap

    Sources of sport confidence, imagery type and performance among competitive athletes: The mediating role of sports confidence

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    Aim: This study explored the mediating role of sport confidence upon (1) sources of sport confidence-performance relationship and (2) imagery-performance relationship. Methods: Participants were 157 competitive athletes who completed state measures of confidence level/sources, imagery type and performance within one hour after competition. Results: Among the current sample, confirmatory factor analysis revealed appropriate support for the nine-factor SSCQ and the five-factor SIQ. Mediational analysis revealed that sport confidence had a mediating influence upon the achievement source of confidence-performance relationship. In addition, both cognitive and motivational imagery types were found to be important sources of confidence, as sport confidence mediated imagery type-performance relationship. Conclusion: Findings indicated that athletes who construed confidence from their own achievements and report multiple images on a more frequent basis are likely to benefit from enhanced levels of state sport confidence and subsequent performance

    Sources of sport confidence, imagery type and performance among competitive athletes: The mediating role of sports confidence

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    Aim: This study explored the mediating role of sport confidence upon (1) sources of sport confidence-performance relationship and (2) imagery-performance relationship. Methods: Participants were 157 competitive athletes who completed state measures of confidence level/sources, imagery type and performance within one hour after competition. Results: Among the current sample, confirmatory factor analysis revealed appropriate support for the nine-factor SSCQ and the five-factor SIQ. Mediational analysis revealed that sport confidence had a mediating influence upon the achievement source of confidence-performance relationship. In addition, both cognitive and motivational imagery types were found to be important sources of confidence, as sport confidence mediated imagery type-performance relationship. Conclusion: Findings indicated that athletes who construed confidence from their own achievements and report multiple images on a more frequent basis are likely to benefit from enhanced levels of state sport confidence and subsequent performance
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