Shrinkage Confidence Procedures

The possibility of improving on the usual multivariate normal confidence was first discussed in Stein (1962). Using the ideas of shrinkage, through Bayesian and empirical Bayesian arguments, domination results, both analytic and numerical, have been obtained. Here we trace some of the developments in confidence set estimation.Comment: Published in at http://dx.doi.org/10.1214/10-STS319 the Statistical Science (http://www.imstat.org/sts/) by the Institute of Mathematical Statistics (http://www.imstat.org

UK Foot and Mouth disease: a systemic risk assessment of existing controls

This article details a systemic analysis of the controls in place and possible interventions available to further reduce the risk of a foot and mouth disease (FMD) outbreak in the United Kingdom. Using a research-based network analysis tool, we identify vulnerabilities within the multibarrier control system and their corresponding critical control points (CCPs). CCPs represent opportunities for active intervention that produce the greatest improvement to United Kingdom's resilience to future FMD outbreaks. Using an adapted ‘features, events, and processes’ (FEPs) methodology and network analysis, our results suggest that movements of animals and goods associated with legal activities significantly influence the system's behavior due to their higher frequency and ability to combine and create scenarios of exposure similar in origin to the U.K. FMD outbreaks of 1967/8 and 2001. The systemic risk assessment highlights areas outside of disease control that are relevant to disease spread. Further, it proves to be a powerful tool for demonstrating the need for implementing disease controls that have not previously been part of the system

A practical low-boom overpressure signature based on minimum sonic boom theory

A brief resume of sonic boom minimization methods is given to provide a background for a new, empirical modification of the Seebass and George minimum-nose-shock sonic boom F-function and signature. The new 'hybrid' F-function has all the inherent flexibility of application found with the Darden-modified Seebass and George F-function. In addition, it has enhanced this flexibility and applicability with neglegible increase in nose and/or tail shock strength. A description of this 'hybrid' F-function and signature is provided, and the benefits of using them to design high-performance, low-boom aircraft are discussed

Akn 564: an unusual component in the X-ray spectra of NLSy1 galaxies

We present an ASCA observation of the NLSy1 Ark 564. The X-ray light curve shows rapid variability, but no evidence for energy-dependence to these variations, within the 0.6 -- 10 keV bandpass. A strong (EW ~ 70 eV) spectral feature is observed close to 1 keV. A similar feature has been observed in TON S180 (another NLSy1) but has not been observed in broad-line Seyfert galaxies. The feature energy suggests a large contribution from Fe L-shell lines but its intensity is difficult to explain in terms of emission and/or absorption from photoionized gas. Models based on gas in thermal equilibrium with kT ~1 keV provide an alternative parameterization of the soft spectrum. The latter may be interpreted as the hot intercloud medium, undergoing rapid cooling and producing strong Fe L-shell recombination lines. In all cases the physical conditions are rather different from those observed in broad-line Seyferts. The hard X-ray spectrum shows a broad and asymmetric Fe Kalpha line of large equivalent width (~550 eV) which can be explained by a neutral disk viewed at ~ 60 degrees to the line-of-sight, contrary to the hypothesis that NLSy1s are viewed pole-on. The large EW of this line, the strong 1 keV emission and the strong optical Fe emission lines all suggest an extreme Fe abundance in this and perhaps other NLSy1s.Comment: 15 pages, 5 figures. LaTeX with encapsulated postscript. Accepted for publication in the Astrophysical Journa

Static internal performance of ventral and rear nozzle concepts for short-takeoff and vertical-landing aircraft

The internal performance of two exhaust system concepts applicable to single-engine short-take-off and vertical-landing tactical fighter configurations was investigated. These concepts involved blocking (or partially blocking) tailpipe flow to the rear (cruise) nozzle and diverting it through an opening to a ventral nozzle exit for vertical thrust. A set of variable angle vanes at the ventral nozzle exit were used to vary ventral nozzle thrust angle between 45 and 110 deg relative to the positive axial force direction. In the vertical flight mode the rear nozzle (or tailpipe flow to it) was completely blocked. In the transition flight mode flow in the tailpipe was split between the rear and ventral nozzles and the flow was vectored at both exits for aircraft control purposes through this flight regime. In the cruise flight mode the ventral nozzle was sealed and all flow exited through the rear nozzle