18,417 research outputs found
Kidson's relation between sunspot number and the movement of high pressure systems in Australia
Kidson's relation is briefly described. It is concluded that if a relation is found between sunspots and weather, it is likely to appear in the march of high and low pressure systems around the poles
A head-up display for mid-air drone recovery
During mid-air retrieval of parachute packages, the absence of a natural horizon creates serious difficulties for the pilot of the recovery helicopter. A head-up display (HUD) was tested in an attempt to solve this problem. Both a roll-stabilized HUD and a no-roll (pitch only) HUD were tested. The results show that fewer missed passes occurred with the roll-stabilized HUD when the horizon was obscured. The pilots also reported that the workload was greatly reduced. Roll-stabilization was required to prevent vertigo when flying in the absence of a natural horizon. Any HUD intended for mid-air retrieval should display pitch, roll, sideslip, airspeed, and vertical velocity
Distribution of periodic points of polynomial diffeomorphisms of C^2
This paper deals with the dynamics of a simple family of holomorphic
diffeomorphisms of \C^2: the polynomial automorphisms. This family of maps
has been studied by a number of authors. We refer to [BLS] for a general
introduction to this class of dynamical systems. An interesting object from the
point of view of potential theory is the equilibrium measure of the set
of points with bounded orbits. In [BLS] is also characterized
dynamically as the unique measure of maximal entropy. Thus is also an
equilibrium measure from the point of view of the thermodynamical formalism. In
the present paper we give another dynamical interpretation of as the
limit distribution of the periodic points of
Aerodynamic characteristics determined during development of the Apollo launch escape vehicle configuration
Aerodynamic characteristics determined during development of Apollo launch escape vehicle configuration in wind tunnel test
Performance Pressure and Resource Allocation in Washington
Based on interviews with state, district, and school officials, explores how performance pressures have changed resource allocation decisions. Examines reform goals and how Washington's finance system impedes efforts to link resources to student learning
Available Telephone Services for Older Virginians Who Are Deaf or Hard of Hearing
Educational Objectives:
1. To identify signs of hearing loss in older adults.
2. To introduce the Virginia Department for the Deaf and Hard of Hearing (VDDHH) and some of its programs and services.
3. To examine three VDDHH services and qualification guidelines.
4. To review how service recipients benefit from these programs
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