6,267 research outputs found
Measured and predicted shock shapes for AFE configuration at Mach 6 in air and in CF4
Shock shapes and stand-off distances were obtained for the Aeroassist Flight Experiment configuration from Mach 6 tests in air and in CF4. Results were plotted for an angle-of attack range from -10 to 10 degrees and comparisons were made at selected angles with inviscid-flow predictions. Tests were performed in the Langley Research Center (LaRC) 20 inch Mach 6 Tunnel (air) at unit free-stream Reynolds numbers (N sub Re, infinity) of 2 million/ft and 0.6 million/ft and in the LaRC Hypersonic CF4 Tunnel at N sub Re, infinity = 0.5 million/ft and 0.3 million/ft. Within the range of these tests, N sub Re, infinity did not affect the shock shape or stand off distance, and the predictions were in good agreement with the measurements. The shock stand-off distance in CF4 was approximately half of that in air. This effect resulted from the differences in density ratio across the normal shock, which was approximately 12 in CF4 and 5 in air. In both test gases, the shock lay progressively closer to the body as angle of attack decreased
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Putting livelihoods thinking into practice: implications for development management.
YesThe failure of `blueprintÂż development interventions to deliver substantive improvements in poverty reduction has been well recognised over the last twenty years. Process approaches seek to overcome the rigidity and top-down operation of much aid-funded intervention. Sustainable livelihoods approaches (SLA) are one of the latest additions to this family of approaches. As a theoretical framework and as a set of principles for guiding intervention, sustainable livelihoods thinking has implications for development management. Drawing on research exploring the application of sustainable livelihoods principles in ten development interventions, this paper considers how these principles have evolved from continuing debates surrounding process and people-centred (bottom-up) approaches to development management. This research suggests that whilst these principles can improve the impact made by interventions, the effective application of sustainable livelihoods and other process approaches are fundamentally restricted by unbalanced power relationships between development partners
Delayed Complementarity: How Schengen Area Membership Influenced German and Austrian Investment in Central and Eastern Europe
This paper considers the mutually beneficial relationship of German and Austrian foreign direct investment (FDI) in Central and Eastern Europe (CEE) between 2004 and 2007, and the impact that the CEE states\u27 belated membership in the Schengen Area had on further economic integration. It analyzes how excluding CEE member states from immediate membership in the Schengen Area upon their accession to the EU in 2004 and 2007 affected the economies of Germany, Austria, and the CEE member states. The paper argues that, in reviewing actual FDI and migration numbers following EU enlargements, fears over the potentially negative effects of labor migration from the New Member States (NMS-10) to the original âold EU-15â members were largely unwarranted. Rather, German and Austrian FDI in CEE created a mutually beneficial relationship between the regions, the potential for which was not fully realized until imposed barriersâlike delayed Schengen membershipâwere finally removed
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Goodbye to Projects? Briefing Paper 1: An Overview: Projects and Principles.
YesThis briefing paper reports on research exploring ten detailed case studies of livelihoods-oriented interventions operating in Tanzania, Lesotho, South Africa and Uganda. Analysing these interventions through an audit of sustainable livelihood `principlesÂż (as a proxy for best practice) revealed general lessons both about the practical opportunities and challenges for employing sustainable livelihoods approaches to the design, implementation, monitoring and evaluation of development interventions and also about the changing format of development interventions.Department for International Developmen
The Individual and Collective Effects of Exact Exchange and Dispersion Interactions on the Ab Initio Structure of Liquid Water
In this work, we report the results of a series of density functional theory
(DFT) based ab initio molecular dynamics (AIMD) simulations of ambient liquid
water using a hierarchy of exchange-correlation (XC) functionals to investigate
the individual and collective effects of exact exchange (Exx), via the PBE0
hybrid functional, non-local vdW/dispersion interactions, via a fully
self-consistent density-dependent dispersion correction, and approximate
nuclear quantum effects (aNQE), via a 30 K increase in the simulation
temperature, on the microscopic structure of liquid water. Based on these AIMD
simulations, we found that the collective inclusion of Exx, vdW, and aNQE as
resulting from a large-scale AIMD simulation of (HO) at the
PBE0+vdW level of theory, significantly softens the structure of ambient liquid
water and yields an oxygen-oxygen structure factor, , and
corresponding oxygen-oxygen radial distribution function, , that
are now in quantitative agreement with the best available experimental data.
This level of agreement between simulation and experiment as demonstrated
herein originates from an increase in the relative population of water
molecules in the interstitial region between the first and second coordination
shells, a collective reorganization in the liquid phase which is facilitated by
a weakening of the hydrogen bond strength by the use of the PBE0 hybrid XC
functional, coupled with a relative stabilization of the resultant disordered
liquid water configurations by the inclusion of non-local vdW/dispersion
interactions
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Goodbye to Projects? Briefing Paper 2: The Application of the SL Principles.
YesThis briefing paper reports on research exploring ten detailed case studies of livelihoods-oriented interventions operating in Tanzania, South Africa, Uganda and Lesotho. As a proxy for best practice, these interventions were analysed through an audit of sustainable livelihood `principlesÂż. This revealed general lessons about both the practical opportunities and challenges for employing sustainable livelihoods approaches to the design, implementation, monitoring and evaluation of development interventions and also about the changing format of development interventions.Department for International Development
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Goodbye to Projects? - Briefing Paper 3: The changing format of development interventions.
yesThis briefing paper reports on research exploring ten detailed case studies of livelihoods-oriented interventions operating in Tanzania, South Africa, Uganda and Lesotho. As a proxy for best practice, these interventions were analysed through an audit of sustainable livelihood `principlesÂż. This revealed general lessons about both the practical opportunities and challenges for employing sustainable livelihoods approaches to the design, implementation, monitoring and evaluation of development interventions and also about the changing format of development interventions.Department for International Development
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