System-Level Integrated Circuit (SLIC) development for phased array antenna applications

A microwave/millimeter wave system-level integrated circuit (SLIC) being developed for use in phased array antenna applications is described. The program goal is to design, fabricate, test, and deliver an advanced integrated circuit that merges radio frequency (RF) monolithic microwave integrated circuit (MMIC) technologies with digital, photonic, and analog circuitry that provide control, support, and interface functions. As a whole, the SLIC will offer improvements in RF device performance, uniformity, and stability while enabling accurate, rapid, repeatable control of the RF signal. Furthermore, the SLIC program addresses issues relating to insertion of solid state devices into antenna systems, such as the reduction in number of bias, control, and signal lines. Program goals, approach, and status are discussed

You Are What You Hear - The Formative Powers of Music

Our choice of music defines what we become. Adults often perceive the musical listening habits of the young as extreme, excusing them because they perceive their choice of music as simply another aspect of their rebellion against authority or society. However, this connection between character, interests, lifestyle, and the music of choice should be extended to include people of every age. Small children and adults are just as affected by the music to which they listen. My purpose in writing this paper was to find evidence for a connection between the music we hear and the people we become. I was especially interested in what ancient scholars such as Augustine, Plato, and other Greek philosophers thought on the issue. I examined twenty books and articles ranging from the ancient Greeks and their views on music to contemporary authors discussing music and its relationship to psychology or humanism. My research indicated that the notion that music changes its listeners is nothing new, but that the correlation between music and moral formation has an ancient history. Even scholars as far back as Plato discussed what sorts of music were appropriate for the young in order to make them into proper members of society. Cultural and political movements rarely happen without music playing a key role in motivating and uniting a group of people into a powerful unit, and the church has certainly utilized the emotional and influential aspects of music in its traditions. This paper examines historical evidence for music as a character-forming force, and discusses how this fact should impact our musical listening choices

Effect of thruster pulse length on thruster-exhaust damage of S13G white thermal control coatings

Rocket exhaust products which strike thermal control surfaces cause changes in solar absorptance (Alpha Sub s) and thermal emittance (Epsilon) of these surfaces. A study was made of the effect of rocket pulse duration on exhaust damage to S13G white coatings. Two pulse lengths were used - 14 msec and 50 msec. An MMH/N204 bipropellant 5-lb thrust rocket was fired into a simulated space environment with a vacuum of 0.00001 torr, a liquid helium temperature enclosure, and solar radiation. The changes in solar absorptance and thermal emittance of S13G white coatings due to rocket exhaust were made in-situ for total firing times of 58 seconds with 14 msec pulses and 223.7 sec with 50 msec pulses. The solar absorptance of S13G increased 25 percent due to 223.7 sec of exposure to 50 msec pulses and the thermal emittance was unaffected. The ratio of Alpha Sub s/Epsilon therefore increased by 25 percent. The short 14 msec pulse exhaust exposure caused between 40 and 70 percent increase in solar absorptance and a decrease of between 13 and 18 percent in thermal emittance. The corresponding increase in Alpha Sub s/Epsilon ratio was between 80 and 100 percent. Ultraviolet radiation was present in the short pulse test and may have contributed to the large damage of that test