Papua New Guinea

Undergraduate 3-

Satellite analog FDMA/FM to digital TDMA conversion

The results of a study which investigated design issues regarding the use of analog to digital (A/D) conversion on board a satellite are presented. The need for A/D, and of course D/A as well, conversion arose from a satellite design which required analog FDMA/FM up and down links to/from a digitally modulated intersatellite link. There are also some advantages when one must interconnect a large number of various spot beams which are using analog, and therefore cannot take advantage of SS/TDMA switching among the beams, thus resulting in low fill factors. Various tradeoffs were performed regarding the implementation of on-board A/D processing, including mass, power, and costs. The various technologies which were considered included flash ADCs, surface acoustic wave (SAW) devices, and digital signal processing (DSP) chips. Impact analyses were also performed to determine the effect on ground stations to convert to digital if the A/D approach were not implemented

Subtraction of Newtonian Noise Using Optimized Sensor Arrays

Fluctuations in the local Newtonian gravitational field present a limit to high precision measurements, including searches for gravitational waves using laser interferometers. In this work, we present a model of this perturbing gravitational field and evaluate schemes to mitigate the effect by estimating and subtracting it from the interferometer data stream. Information about the Newtonian noise is obtained from simulated seismic data. The method is tested on causal as well as acausal implementations of noise subtraction. In both cases it is demonstrated that broadband mitigation factors close to 10 can be achieved removing Newtonian noise as a dominant noise contribution. The resulting improvement in the detector sensitivity will substantially enhance the detection rate of gravitational radiation from cosmological sources.Comment: 29 pages, 11 figure

Communication Platform Payload Definition (CPPD) study. Volume 3: Addendum

This is Volume 3 (Addendum) of the Ford Aerospace & Communications Corporation Final Report for the Communication Platform Payload Definition (CPPD) Study Program conducted for NASA Lewis Research Center under contract No. NAS3-24235. This report presents the results of the study effort leading to five potential platform payloads to service CONUS and WARC Region 2 traffic demand as projected to the year 2008. The report addresses establishing the data bases, developing service aggregation scenarios, selecting and developing 5 payload concepts, performing detailed definition of the 5 payloads, costing them, identifying critical technology, and finally comparing the payloads with each other and also with non-aggregated equivalent services

Keeping Alive the Memory: Modern Philosophies of Myth in Tennyson and Tolkien

Reader response theory states that a literary text is never fully formed until it enters the mind of the reader, who uses his or her personal experiences and understanding of the world to fill in the gaps. Our realities thus influence the stories we read and tell. However, the converse is just as true; the stories we hear, read, and tell throughout our lives leave an indelible mark upon our realities. We all carry within us the narratives of our cultures, which in turn influence the art we create. Alfred, Lord Tennyson and J.R.R. Tolkien both understood this concept and implemented it in their respective works, Idylls of the King and The Lord of the Rings. Though both authors drew from ancient mythic traditions in cultures that viewed myths as superstitions of the past or children’s entertainment, both of their works reflect their cultural situatedness. By displacing current issues of their respective eras into mythical settings of the past, both authors sought to confront what they perceived as problems of their times

A Practical Approach to Service Learning

“Men and Women for Others” is a core Ignatian value. Often, however, when teaching working adults—adults with full-time jobs, families, and a host of other obligations—it is more challenging to incorporate Service Learning into prescribed coursework. This article provides a very practical description of how adult learners can be engaged in Service Learning projects—projects that enhance their learning, their lives, and their communities