Evaluation of a stall-flutter spring-damper pushrod in the rotating control system of a CH-54B helicopter

Results of a design and flight test program conducted to define the effect of rotating pushrod damping on stall-flutter induced control loads are presented. The CH-54B helicopter was chosen as the test aircraft because it exhibited stall induced control loads. Damping was introduced into the CH-54B control system by replacing the standard pushrod with spring-damper assemblies. Design features of the spring-damper are described and the results of a dynamic analysis are shown which define the pushrod stiffness and damping requirements. Flight test measurements taken at 47,000 lb gross weight with and without the damper are presented. The results indicate that the spring-damper pushrods reduced high frequency, stall-induced rotating control loads by almost 50%. Fixed system control loads were reduced by 40%. Handling qualities in stall were unchanged, as expected

New Public Management And Service Science: Preparing Students For The 21st Century

This effort will seek to discover the foundations of public management and how it relates to information technology, specifically understanding E-government and other technologies in the public domain. Public Management is the development or application of methodical and systematic techniques, often employing comparison quantification, and measurement, that are designed to make the operations of public organizations more efficient, effective and increasingly responsive. This is a considerably crisper, concise, and narrow definition compared to other definitions of public administration, and its sharper focus is attributable to the larger fields encompassing of values in addition to those of efficiency, effectiveness and responsiveness

Vector magnetometer design study: Analysis of a triaxial fluxgate sensor design demonstrates that all MAGSAT Vector Magnetometer specifications can be met

The design of the vector magnetometer selected for analysis is capable of exceeding the required accuracy of 5 gamma per vector field component. The principal elements that assure this performance level are very low power dissipation triaxial feedback coils surrounding ring core flux-gates and temperature control of the critical components of two-loop feedback electronics. An analysis of the calibration problem points to the need for improved test facilities

Hyperspherical Harmonics, Separation of Variables and the Bethe Ansatz

The relation between solutions to Helmholtz's equation on the sphere $S^{n-1}$ and the [{\gr sl}(2)]^n Gaudin spin chain is clarified. The joint eigenfuctions of the Laplacian and a complete set of commuting second order operators suggested by the $R$--matrix approach to integrable systems, based on the loop algebra \wt{sl}(2)_R, are found in terms of homogeneous polynomials in the ambient space. The relation of this method of determining a basis of harmonic functions on $S^{n-1}$ to the Bethe ansatz approach to integrable systems is explained.Comment: 14 pgs, Plain Tex, preprint CRM--2174 (May, 1994

New Observables for Parity Violation in Atoms: Energy Shifts in External Electric Fields

We consider hydrogen-like atoms in unstable levels of principal quantum number n=2, confined to a finite size region in a non-homogeneous electric field carrying handedness. The interplay between the internal degrees of freedom of the atoms and the external ones of their c.m. motion can produce P-odd contributions to the eigenenergies. The nominal order of such shifts is 10^-8 Hz. Typically such energy shifts depend linearly on the small P-violation parameters delta_i similarequal 10^-12 (i=1,2), essentially the ratios of the P-violating mixing matrix elements of the 2S and 2P states over the Lamb shift, with i=1 (i=2) corresponding to the nuclear spin independent (dependent) term. We show how such energy shifts can be enhanced by a factor of similarequal 10^6 in a resonance like way for special field configurations where a crossing of unstable levels occurs, leading to P-violating effects proportional to squareroot{delta_i}. Measurements of such effects can give information concerning the ``spin crisis'' of the nucleons.Comment: 6 pages, 3 figures, LaTeX, submitted to Phys. Lett.

Large deviations for many Brownian bridges with symmetrised initial-terminal condition

Consider a large system of $N$ Brownian motions in $\mathbb{R}^d$ with some non-degenerate initial measure on some fixed time interval $[0,\beta]$ with symmetrised initial-terminal condition. That is, for any $i$, the terminal location of the $i$-th motion is affixed to the initial point of the $\sigma(i)$-th motion, where $\sigma$ is a uniformly distributed random permutation of $1,...,N$. Such systems play an important role in quantum physics in the description of Boson systems at positive temperature $1/\beta$. In this paper, we describe the large-N behaviour of the empirical path measure (the mean of the Dirac measures in the $N$ paths) and of the mean of the normalised occupation measures of the $N$ motions in terms of large deviations principles. The rate functions are given as variational formulas involving certain entropies and Fenchel-Legendre transforms. Consequences are drawn for asymptotic independence statements and laws of large numbers. In the special case related to quantum physics, our rate function for the occupation measures turns out to be equal to the well-known Donsker-Varadhan rate function for the occupation measures of one motion in the limit of diverging time. This enables us to prove a simple formula for the large-N asymptotic of the symmetrised trace of ${\rm e}^{-\beta \mathcal{H}_N}$, where $\mathcal{H}_N$ is an $N$-particle Hamilton operator in a trap

The Consequences And Public Policy Implications Of Welfare Reform: A Cost-Benefit Analysis Of The Welfare Reform Policy

Welfare reform has been the recurrent subject of heated debate in the United States, culminating in far-reaching legislation in 1996.  Taking the measure of that legislation requires attention both to the broader context of which welfare policy is a part and to the merits of the 1996 law itself.  Ultimately, the success or failure of welfare reform, which evoked a great deal of partisan rhetoric, will be assessed on empirical rather than partisan grounds.  It cannot be determined merely by changes in the size of welfare caseloads.  It is crucial to any piece of legislation to analyze the cost in relations to its benefits.  Most importantly, we must ask: What has happened to the families and children who have left the welfare system?  Personal Responsibility and Work Opportunity Reconciliation Act of 1996 is a successful legislation that needs a little troubleshooting, so it will not be the failed anti-poverty prescriptio