19 research outputs found

    MATLAB Modeling of OFDM Modulation Technique Across a 24 kHz, 48 kHz, and 3 MHz Bandwidth in the High-Frequency Radio Band (3-30) MHz

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    The goal of this project is to use MATLAB to model orthogonal frequency division multiplexing (OFDM) modulation technique across 24 kHz, 48 kHz, and 3 MHz bandwidths in the high frequency (HF) radio band (3-30 MHz). The purpose of our design is to make HF long distance communication faster and more reliable so that every part of the world, including the most remote parts, will have access to high speed, long distance wireless communication. Our MATLAB model will allow us to modify the bandwidth, carrier frequency, modulation type, signal to noise ratio (SNR), and image size to determine which combination of parameters provides reliable OFDM data transmissions in the HF radio band. To determine the success of our model, we will calculate the data rate and the bit to error ratio (BER) after data transmission. Ideally, we would like to have a BER of 10-5 for an SNR that is representative of the noise level experienced in the ionosphere. This report describes the current design of our MATLAB model and presents the results for the set of parameters that will achieve the best data transmission in the HF radio band

    Characterization of Plastic Degrading Bacteria from Environmental Samples by Genetic and Biochemical Analysis

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    Plastic is the major waste-product during NASA space missions, recycling this waste-stream to produce other beneficial materials would decrease upmass. Bacterial called plastisomes have been demonstrated to metabolize non-biodegradable plastics such as polyethylene and polystyrene. Characterization and engineering of these bacteria, and their eventual incorporation as life support systems would enable space flight beyond lower earth orbit. We will utilize molecular techniques to identify and isolate the most productive plastisome. Environmental samples obtained from locations known to be rich in plastic will be cultured in a laboratory defined-media supplemented with plastic as the sole carbon source. Cultures will be monitored for growth over time. Ribosomal DNA will be amplified from cultures that exhibit growth using PCR. These amplified fragments will be sequenced to determine the identity of the consortia in the cultures. We will then perform bioinformatics analysis on the data to identify the plastisomes and generate phylogenetic trees. Morphological and physiological profile of the plastisomes will also be conducted by microscopy and biochemical tests. Our results would reveal a bacterial strain that can break down plastics efficiently. The implication for this project would not only benefit space exploration but also make a major impact towards sustainability development on Earth

    Bacterial Degradation of Plastics

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    Plastics are not only a major component of societies on Earth but also those in Space. After use, plastics can accumulate and become difficult to recycle or reuse. Finding ways to degrade and recycle synthetic plastics would provide a way to reduce the upmass of Space Travel, create a closed-loop system of resources and even benefit life on Earth. The purpose of this project is to identify and characterize bacterial species that can degrade and recycle plastics. It has been suggested that bacteria can use plastics, like polyethylene and polystyrene, as a carbon source. These plastics are broken down into intermediary molecules which can then be used in the bacterium's metabolism. Environmental samples were collected from various locations rich in plastic waste. These samples are currently being used to culture bacteria in M9 minimal media containing polyethylene and polystyrene beads as the sole carbon source. High Performance Liquid Chromatography (HPLC), Scanning Electron Microscopy (SEM), and DNA sequencing are among the various methods that will be used identify and characterize bacteria that can degrade plastics. The results from these experiments will provide methods to reduce waste of plastics and ultimately improve sustainability for long-term space exploration

    Who teaches writing?

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    Who Teaches Writing is an open teaching and learning resource being used in English Composition classes at Oklahoma State University. It was authored by contributors from Oklahoma State University and also includes invited chapters from other institutions both inside and outside of Oklahoma. Contributors include faculty from various departments, contingent faculty and staff, and graduate instructors. One purpose of the resource is to provide short, relatively jargon-free chapters geared toward undergraduate students taking First-Year Composition. Support for this project was provided in part by OpenOKState and Oklahoma State University Libraries.OpenOKStateOklahoma State University LibrariesLibraryEnglis

    Registered Ship Notes

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    https://digitalmaine.com/blue_hill_documents/1179/thumbnail.jp

    Forty years among the Zulus

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    Includes appendix on later missions.Mode of access: Internet
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