5,323 research outputs found
Design hazard analysis, and system level testing of a university propulsion system for spacecraft application
The Missouri Science and Technology Satellite (M-SAT) design team on the campus of the Missouri University of Science and Technology has developed a pair of satellites to perform an autonomous formation flight mission. To enable the mission, a unique cold gas propulsion system was developed which utilizes the refrigerant R-134a as propellant. This thesis details the design process and considerations which led to the propulsion system as integrated into the satellite for the Flight Competition Review of the NS4 competition. The design process described flowed from the mission requirements and program restrictions down through component-level requirements and resulted in a system capable of performing the assigned duties. The hazard analysis conducted for this thesis also expanded on previous analyses to address key issues and AFRL concerns --Abstract, page iii
Building Blocks in the Economics of Mandates
The paper constructs an asymmetric information model to investigate the efficiency and equity cases for government mandated benefits. A mandate can improve workers' insurance, and may also redistribute in favour of more "deserving" workers. The risk is that it may also reduce output. The more diverse are free market contracts – separating the various worker types – the more likely it is that such output effects will on balance serve to reduce welfare. It is shown that adverse effects can be reduced by restricting mandates to larger firms. An alternative to a mandate is direct government provision. We demonstrate that direct government provision has the advantage over mandates of preserving separations.asymmetric information, labour mandates, compensation packages
Applying mesh conformation on shape analysis with missing data
A mesh conformation approach that makes use of deformable generic meshes has been applied to establishing correspondences between 3D shapes with missing data. Given a group of shapes with correspondences, we can build up a statistical shape model by applying principal component analysis (PCA). The conformation at first globally maps the generic mesh to the 3D shape based on manually located corresponding landmarks, and then locally deforms the generic mesh to clone the 3D shape. The local deformation is constrained by minimizing the energy of an elastic model. An algorithm was also embedded in the conformation process to fill missing surface data of the shapes. Using synthetic data, we demonstrate that the conformation preserves the configuration of the generic mesh and hence it helps to establish good correspondences for shape analysis. Case studies of the principal component analysis of shapes were presented to illustrate the successes and advantages of our approach
Azimuth axis optical alignment system Final report
Azimuth axis optical alignment system to monitor and measure attitude or angular position of remote object about azimuth axis using phase information imposed on returning beam of ligh
Stellar Motion around Spiral Arms: Gaia Mock Data
We compare the stellar motion around a spiral arm created in two different
scenarios, transient/co-rotating spiral arms and density-wave-like spiral arms.
We generate Gaia mock data from snapshots of the simulations following these
two scenarios using our stellar population code, SNAPDRAGONS, which takes into
account dust extinction and the expected Gaia errors. We compare the observed
rotation velocity around a spiral arm similar in position to the Perseus arm,
and find that there is a clear difference in the velocity features around the
spiral arm between the co-rotating spiral arm and the density-wave-like spiral
arm. Our result demonstrates that the volume and accuracy of the Gaia data are
sufficient to clearly distinguish these two scenarios of the spiral arms.Comment: 5 pages, 1 figure, to appear in the proceedings of "The Milky Way
Unravelled by Gaia: GREAT Science from the Gaia Data Releases", Barcelona,
1-5 December 2014, eds. N. Walton, F. Figueras, C. Soubira
In-Vitro-Experiments on the Dissolution of Ca-Oxalate and Ca-Phosphate Renal Calculi by the Tricarboxylic Acids of the Krebs-Cycle. Results and in Vivo Perspectives
The nephrolithiasis is the most frequent urological disease.1•2 The stone
incidence in general is 1-4°/o and can be compared with that of diabetes
mellitus
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