5,635 research outputs found

    The NASA-Lewis/ERDA solar heating and cooling technology program

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    Plans by NASA to carry out a major role in a solar heating and cooling program are presented. This role would be to create and test the enabling technology for future solar heating, cooling, and combined heating/cooling systems. The major objectives of the project are to achieve reduction in solar energy system costs, while maintaining adequate performance, reliability, life, and maintenance characteristics. The project approach is discussed, and will be accomplished principally by contract with industry to develop advanced components and subsystems. Advanced hardware will be tested to establish 'technology readiness' both under controlled laboratory conditions and under real sun conditions

    Technical and economic feasibility study of solar/fossil hybrid power systems

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    Results show that new hybrid systems utilizing fossil fuel augmentation of solar energy can provide significant capital and energy cost benefits when compared with solar thermal systems requiring thermal storage. These benefits accrue from a reduction of solar collection area that results from both the use of highly efficient gas and combined cycle energy conversion subsystems and elimination of the requirement for long-term energy storage subsystems. Technical feasibility and fuel savings benefits of solar hybrid retrofit to existing fossil-fired, gas and vapor cycle powerplants was confirmed; however, economic viability of steam cycle retrofit was found to be dependent on the thermodynamic and operational characteristics of the existing powerplant

    Historical perspectives: The role of the NASA Lewis Research Center in the national space nuclear power programs

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    The history of the NASA Lewis Research Center's role in space nuclear power programs is reviewed. Lewis has provided leadership in research, development, and the advancement of space power and propulsion systems. Lewis' pioneering efforts in nuclear reactor technology, shielding, high temperature materials, fluid dynamics, heat transfer, mechanical and direct energy conversion, high-energy propellants, electric propulsion and high performance rocket fuels and nozzles have led to significant technical and management roles in many national space nuclear power and propulsion programs

    Reliability and mass analysis of dynamic power conversion systems with parallel of standby redundancy

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    A combinatorial reliability approach is used to identify potential dynamic power conversion systems for space mission applications. A reliability and mass analysis is also performed, specifically for a 100 kWe nuclear Brayton power conversion system with parallel redundancy. Although this study is done for a reactor outlet temperature of 1100K, preliminary system mass estimates are also included for reactor outlet temperatures ranging up to 1500 K

    A framework for a joint hydro-meteorological-social analysis of drought

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    This article presents an innovative framework for analysing environmental governance challenges by focusing on their Drivers, Responses and Impacts (DRI). It builds on and modifies the widely applied Drivers, Pressures, States, Impacts and Responses (DPSIR) model. It suggests, firstly and most importantly, that the various temporal and spatial scales at which Drivers, Responses and Impacts operate should be included in the DRI conceptual framework. Secondly, the framework focuses on Drivers, Impacts and Responses in order to provide a parsimonious account of a drought system that can be informed by a range of social science, humanities and science data. ‘Pressures’ are therefore considered as a sub-category of ‘Drivers’. ‘States’ are a sub-category of ‘Impacts’. Thirdly, and most fundamentally in order to facilitate cross-disciplinary research of droughts, the DRI framework defines each of its elements, ‘Drivers’, ‘Pressures’, ‘States’, ‘Impacts’ and ‘Responses’ as capable of being shaped by both linked natural and social factors. This is different from existing DPSIR models which often see ‘Responses’ and ‘Impacts’ as located mainly in the social world, while ‘States’ are considered to be states within the natural environment only. The article illustrates this argument through an application of the DRI framework to the 1976 and 2003–6 droughts. The article also starts to address how - in cross-disciplinary research that encompasses physical and social sciences – claims about relationships between Drivers as well as Impacts of and Responses to drought over time can be methodologically justified. While the DRI framework has been inductively developed out of research on droughts we argue that it can be applied to a range of environmental governance challenges

    Carton packs for granny smith apples

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    THE demand for bruise-free apples by overseas buyers has been mainly responsible for the development of fibre board cartons as export apple containers

    Preparation of fruit for marketing — part 2 — handling, grading and sizing

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    The orchardist\u27s careful attention to such operations as pruning, spraying and thinning in his effort to grow good quality fruit may be nullified to a large extent by carelessness at harvesting or during the subsequent period of handling before the fruit reaches the consumer. The grower cannot afford to become careless at any stage for every injury to the skin surface or underlying tissues of the fruit will ultimately show up as a bruise, puncture or other blemish. Many of these injuries may not be noticeable at the time of picking but will be only too obvious when the fruit is offered for sale

    Sensational apple yields - Is this an Australian record?

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    Msssers. A. J PREECE & SONS of Keysbrook, are the proud owners of an apple orchard which has maintained some amazing production figures for many years. This year\u27s yield of 5,609 packed cases from 347 trees is still 264 cases less than the record yield in 1953, when the trees were 17 years old

    Quantitative electron probe microanalysis of light elements using energy dispersive x-ray spectrometry.

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    SIGLELD:D48055/83 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
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