First
Place
The Effect of a Ground Reflector on Long Wavelength
Development Array (LWDA) Antenna Performance
By Erika Hetherington
Westwood High School
Supervisor: Dr. David Munton, Space &
Geophysics Laboratory, ARL:UT
Abstract
The Long Wavelength Development
Array (LWDA) is a prototype for the planned Long Wavelength
Array (LWA), a large radio astronomy telescope to be
located throughout New Mexico. Researchers from ARL:UT
have developed an antenna prototype to be used in the
LWDA. The objective of this project is to investigate
the impact of placing a metal ground reflector beneath
the antenna. Several tests were conducted, including
measurements of antenna gain with and without a ground
reflector, over multiple angles of signal reception.
Also measurements were taken of antenna impedance matching
with and without a ground reflector. Finally, sky noise
measurements were performed. Measured data was compiled
and analyzed using computer scripts, and was then compared
to results from computer simulations. From this analysis,
conclusions are drawn as to the improvement in antenna
performance due to installing a ground plane.
Second Place
Light Bulbs as an Underwater Acoustic Source 
By Shaun Sherman
Waller High School
Supervisor: Dr. David Knobles, Environmental Sciences Laboratory,
ARL:UT
Abstract
Over the years, underwater sources have
varied greatly in type, efficiency, and cost. Explosive
TNT sources such as Sound Underwater Signaling (SUS) were
popular for many years. However, recent environmental restrictions
have put a halt to use of this type of underwater source.
The intrinsic properties of a light bulb make it a useful
source for generating underwater sound. When the bulb is
placed below the surface of the water, the vacuum inside
the bulb allows an implosion to occur when the glass shell
is compromised. This forms a bubble, which oscillates at
a diminishing level until all the ambient potential energy
is transformed into mechanical energy, sound radiation,
and heat. The purpose of this project is to accurately measure
the characteristics of light bulb implosion source waveforms
as a function of depth of implosion and evacuated volume
of the light bulb.
Third Place
 Operational
& Capability Enhancements for a Railgun Bore Inspection
Tool
Joint project by Dean Porter and a student
from Trinity High School
Pflugerville High School
Supervisor: Dr. John Mallick, Institute for Advanced Technology
Abstract
The purpose
of our project has been to design and build a replacement
for a bore inspection tool that was created last year. Our
supervisors supplied us with some general guidelines of
the capabilities and features that we should incorporate
into our device, as well as various ways to improve previous
features of the older device. The purpose of having such
a tool is for assessing damage that occurs inside the bore
of a rail gun after every launch, without having to disassemble
the gun. Our tool is in the form of a small robotic vehicle,
with a miniature camera mounted on the front, drive train
and an encoder setup to transmit distance data back to the
operator. The entire setup is wireless for ease of use,
and required a good amount of custom fabrication, programming
and electrical engineering knowledge and research to complete.
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