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

Articulating the Teacher: Gottlieb, Dreyfus, and Heidegger on Language

Standardization has become a ubiquitous feature in the field of education both through federal initiatives, such as the establishment of “best practices” distilled from randomized controlled trials (RCTs), and through private businesses and non-profits, such as Facebook and the Gates Foundation, which create and disseminate prefabricated curricula and standardized software programs. Standardization requires, as a precondition, the generalization of research findings from a smaller subset of teachers, students, or schools, to the field of education in its entirety. This dissertation investigates whether generalization of this sort is possible or desirable. After explaining why current critiques of educational generalization are insufficient, the author argues that, though generalizing from RCTs is ontologically precluded, generalization of a different sort is both possible and desirable. The author employs Martin Heidegger’s ontological analysis of language to argue for a weak form of generalizability that avoids the extremes of RCT-based best practices while allowing teaching to be discussed across spatial and temporal locations

Comparison of Foldit Calculated Stability with Experimentally Determined Energy Values of Cytochrome C Mutants

Foldit Standalone software is a program that allows for structural manipulation of proteins. It can be used to observe the 3-dimensional structure of proteins, calculating the relative stability of the protein. Mutations can be made to the structure of the protein on Foldit, which can then have stability values calculated as well. Foldit can be used to minimize energy values of proteins, measuring changes in energy due to mutations and in the end providing a Foldit energy value. In our work, we seek to use Foldit to calculate energy values of a mutated protein, then compare these values to those calculated in experiment, overall establishing a basis for comparison of the Foldit energy values. We observed Cytochrome C (Cyt c) , a small heme protein that functions in the electron transport chain. Previously done work observed the protein unfolding of Cyt c, then spectroscopically analyzed the protein through fluorescence, absorbance, and circular dichroism, allowing for calculations of Gibbs free energy of specific mutations to be made. Using Foldit, we were able to view these mutations, observing their effects on energy values and protein stability. In comparing the energy values calculated from Foldit with those spectroscopically measured, we can understand the degree of accuracy that Foldit predicts protein stability with. We were particularly interested in observing Cyt c because Foldit ignores prosthetic groups, meaning it does not consider heme groups. This fact made us particularly interested in seeing how Foldit energy values would compare to experimental energy values