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Crotalus ruber
Number of Pages: 17Integrative BiologyGeological Science
Status of advanced turboprop technology
Research is reviewed in the following areas: turboprop powered transport aircraft; wind tunnel aerodynamic and acoustics tests of model propellers; turboprop maintenance; and wind tunnel tests on airframe-turboprop interactions. Continued development of the technology for advanced turboprop transport was emphasized
Putting the Glee Club to the Test: Reconsidering Mandatory Suspicionless Drug Testing of Students Participating in Extracurricular Activities;Note
Reparameterization Invariance to all Orders in Heavy Quark Effective Theory
Heavy Quark Effective Theory splits a heavy quark momentum into a large fixed
momentum and a variable residual momentum, p = m_Q v + k. It thereby suffers a
redundancy of description corresponding to small changes in the choice of the
fixed velocity, v. The fact that full QCD is manifestly v-independent should
lead to a non-trivial constraint on the form of the effective theory, known as
Reparameterization Invariance. For spin-1/2 quarks, the precise form of the
constraint and its solution at the level of the effective lagrangian have
proven to be rather subtle, and the original proposal by Luke and Manohar has
been questioned. In this paper I employ a version of Heavy Quark Effective
Theory containing the ``anti-particle'' field as a non-propagating auxiliary
field, which greatly simplifies keeping track of v-dependence. This permits a
very simple derivation of Reparameterization Invariance from first principles.
The auxiliary field can also be integrated out to return to the standard
formulation of the effective theory, but with the effective lagrangian now
satisfying the full reparameterization constraint. I compare this result with
earlier proposals.Comment: 12 pages, LaTex. Important and confusing typographical error in eq.
(15) corrected. To appear in Phys. Rev.
Teachers\u27 Tort Liability
The recent notoriety in the Cleveland area attendant upon several reports of alleged batteries committed by teachers has served to focus the attention of both the educator and the citizen on this aspect of liability. This attention may well result in some necessary judicial and legislative clarification in this area, but it may tend to obscure other equally important facets of the teacher\u27s tort liability. It is with this thought in mind that this article is written. The article itself is intended as much for teachers as it is for attorneys. Where possible, it attempts to transcend the attorney\u27s usual interest in event which have already occurred and seeks to present rules for guidance
Putting the Glee Club to the Test: Reconsidering Mandatory Suspicionless Drug Testing of Students Participating in Extracurricular Activities;Note
Helical automatic approaches of helicopters with microwave landing systems
A program is under way to develop a data base for establishing navigation and guidance concepts for all-weather operation of rotorcraft. One of the objectives is to examine the feasibility of conducting simultaneous rotorcraft and conventional fixed-wing, noninterfering, landing operations in instrument meteorological conditions at airports equipped with microwave landing systems (MLSs) for fixed-wing traffic. An initial test program to investigate the feasibility of conducting automatic helical approaches was completed, using the MLS at Crows Landing near Ames. These tests were flown on board a UH-1H helicopter equipped with a digital automatic landing system. A total of 48 automatic approaches and landings were flown along a two-turn helical descent, tangent to the centerline of the MLS-equipped runway to determine helical light performance and to provide a data base for comparison with future flights for which the helical approach path will be located near the edge of the MLS coverage. In addition, 13 straight-in approaches were conducted. The performance with varying levels of state-estimation system sophistication was evaluated as part of the flight tests. The results indicate that helical approaches to MLS-equipped runways are feasible for rotorcraft and that the best position accuracy was obtained using the Kalman-filter state-estimation with inertial navigation systems sensors
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