Conceptual study of on orbit production of cryogenic propellants by water electrolysis

The feasibility is assessed of producing cryogenic propellants on orbit by water electrolysis in support of NASA's proposed Space Exploration Initiative (SEI) missions. Using this method, water launched into low earth orbit (LEO) would be split into gaseous hydrogen and oxygen by electrolysis in an orbiting propellant processor spacecraft. The resulting gases would then be liquified and stored in cryogenic tanks. Supplying liquid hydrogen and oxygen fuel to space vehicles by this technique has some possible advantages over conventional methods. The potential benefits are derived from the characteristics of water as a payload, and include reduced ground handling and launch risk, denser packaging, and reduced tankage and piping requirements. A conceptual design of a water processor was generated based on related previous studies, and contemporary or near term technologies required. Extensive development efforts would be required to adapt the various subsystems needed for the propellant processor for use in space. Based on the cumulative results, propellant production by on orbit water electrolysis for support of SEI missions is not recommended

Big data brings new power to open-source intelligence

The story of Eliot Higgins, a blogger who exploits publicly accessible material to piece together important facts about the Syrian conflict, offers a unique insight into the enormous potential of open-source intelligence. Matthew Moran describes how the networked society has spawned new analytical approaches and opportunities

Hydrogen no-vent fill testing in a 5 cubic foot (142 liter) tank using spray nozzle and spray bar liquid injection

A total of 38 hydrogen no-vent fill tests were performed in this test series using various size spray nozzles and a spray bar with different hole sizes in a 5 cubic foot receiver tank. Fill levels of 90 percent by volume or greater were achieved in 26 of the tests while maintaining a receiver tank pressure below 30 psia. Spray nozzles were mounted at the top of the tank, whereas, the spray bar was centered in the tank axially. The spray nozzle no-vent fills demonstrated tank pressure and temperature responses comparable to previous test series. Receiver tank pressure responses for the spray bar configuration were similar to the spray nozzle tests with the pressure initially rising rapidly, then leveling off as vapor condenses onto the discharging liquid streams, and finally ramping up near the end of the test due to ullage compression. Both liquid injection techniques tested were capable of filling the receiver tank to 90 percent under variable test conditions. Comparisons between the spray nozzle and spray bar configurations for well matched test conditions indicate the spray nozzle injection technique is more effective in minimizing the receiving tank pressure throughout a no-vent fill compared to the spray bar under normal gravity conditions

Improving Big Data Visual Analytics with Interactive Virtual Reality

For decades, the growth and volume of digital data collection has made it challenging to digest large volumes of information and extract underlying structure. Coined 'Big Data', massive amounts of information has quite often been gathered inconsistently (e.g from many sources, of various forms, at different rates, etc.). These factors impede the practices of not only processing data, but also analyzing and displaying it in an efficient manner to the user. Many efforts have been completed in the data mining and visual analytics community to create effective ways to further improve analysis and achieve the knowledge desired for better understanding. Our approach for improved big data visual analytics is two-fold, focusing on both visualization and interaction. Given geo-tagged information, we are exploring the benefits of visualizing datasets in the original geospatial domain by utilizing a virtual reality platform. After running proven analytics on the data, we intend to represent the information in a more realistic 3D setting, where analysts can achieve an enhanced situational awareness and rely on familiar perceptions to draw in-depth conclusions on the dataset. In addition, developing a human-computer interface that responds to natural user actions and inputs creates a more intuitive environment. Tasks can be performed to manipulate the dataset and allow users to dive deeper upon request, adhering to desired demands and intentions. Due to the volume and popularity of social media, we developed a 3D tool visualizing Twitter on MIT's campus for analysis. Utilizing emerging technologies of today to create a fully immersive tool that promotes visualization and interaction can help ease the process of understanding and representing big data.Comment: 6 pages, 8 figures, 2015 IEEE High Performance Extreme Computing Conference (HPEC '15); corrected typo

Microbial diversity in the thermal springs within Hot Springs National Park

The thermal water systems of Hot Springs National Park (HSNP) in Hot Springs, Arkansas exist in relative isolation from other North American thermal systems. The HSNP waters could therefore serve as a unique center of thermophilic microbial biodiversity. However, these springs remain largely unexplored using culture-independent next generation sequencing techniques to classify species of thermophilic organisms. Additionally, HSNP has been the focus of anthropogenic development, capping and diverting the springs for use in recreational bathhouse facilities. Human modification of these springs may have impacted the structure of these bacterial communities compared to springs left in a relative natural state. The goal of this study was to compare the community structure in two capped springs and two uncapped springs in HSNP, as well as broadly survey the microbial diversity of the springs. We used Illumina 16S rRNA sequencing of water samples from each spring, the QIIME workflow for sequence analysis, and generated measures of genera and phyla richness, diversity, and evenness. In total, over 700 genera were detected and most individual samples had more than 100 genera. There were also several uncharacterized sequences that could not be placed in known taxa, indicating the sampled springs contain undescribed bacteria. There was great variation both between sites and within samples, so no significant differences were detected in community structure between sites. Our results suggest that these springs, regardless of their human modification, contain a considerable amount of biodiversity, some of it potentially unique to the study site

Testing the predictability of water-based flexographic inks on plastic substrates

The purpose of this thesis was to investigate the applications of surface energy measurements in predicting the ink adhesion of four different Fasson plastic substrates using the flexographic printing process and water -based inks. These four plastic substrates are as follows: Clear P.E.T., Clear Acetate, Polystyrene, Vinyl. These films were identified by Fasson as substrates they believe to have poor adhesion. The aim was to develop a method to predict ink adhesion of these plastic surfaces by correlating a surface energy test on the substrate before printing begins to ink adhesion tests of the finished print. Water -based inks offer many advantages over traditional solventbased inks. They are as follows: 1. They are physiologically safer. 2. They don\u27t burn. 3. They don\u27t cause air pollution. 4. They are tasteless and odor less. 5. Water -based inks are less expensive to store, to transport, and to produce. 6. Water is available in large quantities. The use of water -based inks is becoming more popular not only because of increased government regulations and insurance problems IV for solvent ink users, but because water -based inks produce cleaner prints, more consistent colors and faster washups. Water -based inks unfortunately don\u27t wet a surface as good as solvent-based inks. This was the basis for this type of research

Going To The Movies: Immersion, Visual Awareness, And Memory

Immersion describes the extent of which one feels involved in a virtual experience. In immersive environments, observers report high levels of sensory interaction, story engagement, and an impression of reality. According to the concept of Inattentional Blindness (IB), many people can miss an unexpected stimulus or object even if it is in their field of vision while attending to a task. Can immersion affect susceptibility to IB, and can it affect memory performance? To answer this question, two model theaters were used in order to manipulate a person\u27s assessment of being immersed in two experiments. A realistic condition used a model of a movie theater complete with curtains, seats, wallpaper, working wall sconces, and patrons. A haphazard condition (control) used a model of the same size, but materials were used in a way that does not resemble a movie theater. Both conditions used an IB paradigm apparatus housed beneath the stage area that moved an unexpected stimulus (movie patron or bolt) in front of a movie screen. Upon completion of a movie clip, participants were first asked if they noticed the unexpected object, and to describe what they noticed. Immersion was then measured using Jennett et al.\u27s (2008; International Journal of Human Computer Studies) questionnaire, and memory was assessed with a 10-question multiple-choice test about the movie clip. Results did not show a clear relationship between immersion and IB. Differences between groups were marginal for immersion, IB, and memory

Experiences from semantic web service tutorials

We have given around 20 tutorials on Semantic Web Services in international events during the last two years. This position paper presents our experiences and depicts central aspects relevant for education, dissemination and exploitation of Semantic Web and Semantic Web service technologies in academia and industry

Initial experimentation on the nonvented fill of a 0.14m3 (5 ft. 3) dewar with nitrogen and hydrogen

A series of nonvented fills were performed on a 0.14 cu m (5 cu ft) stainless steel dewar. Fills were conducted with a 120 deg cone angle spray nozzle over a range of inflow and initial wall temperatures with both liquid nitrogen and liquid hydrogen. Fill levels in excess of 85 percent liquid were achieved for four out of four nitrogen and two out of five hydrogen tests. Previously developed analytical models were compared to the test results and shown to have general trend agreement