5,318 research outputs found
Covering Arrays and Fault Detection
Given their several applications, covering arrays have become a topic of significance over the last twenty years in both the mathematical and computer science fields. A covering array is a N × k array with strength t, k rows of length N, entries from the set {0, 1, ..., v − 1}, and all vt possible combinations occur between any t columns, where N,k,t, and v are positive integers. The focus of our research was to explore the different constructions of strength two and strength three covering arrays, to find better covering arrays (i.e. more cost and time efficient covering arrays), and to see if covering arrays can detect a fault in a system. Through analyzing the covering arrays that we constructed, we were able to successfully prove that in general, a covering array of strength k + 1 can detect a single fault between any k or fewer variables in a system. Some areas of future research would include finding the location of a fault in a system or detecting two or more faults in a system
Carbon conversion efficiency and 13C labeling of the tricarboxylic acid cycle in lesquerella
Biological Sciences: 1st Place (The Ohio State University Denman Undergraduate Research Forum)Lesquerella (Physaria fendleri) is a Brassicaceae that produces a valuable class of compounds in its embryos called hydroxy fatty acids. These fatty acids are used widely in industry to produce cosmetics, coatings, greases, plastics, paints, and biofuel, among others. The current source of hydroxy fatty acids is ricinoleic acid from the castor plant (Ricinus communis), which also produces the highly toxic compound ricin that has eliminated castor plant cultivation in the United States. Lesquerella produces lesquerolic acid, a hydroxy fatty acid with only two additional carbons as compared to ricinoleic acid, which therefore performs in a chemically similar manner. Since it is non-toxic and already grows in the wild in the southwest US as a winter annual that will not compete with food crops, lesquerella could serve as a suitable alternative to castor oil. However to become economically viable, lesquerella first must be engineered to produce more of these fatty acids to meet demands. The most recent work done towards meeting this end goal is: (i) quantifying the development of the biomass components of lesquerella embryos in planta (fatty acids, starch, protein, and cell wall); (ii) identifying culture conditions for growing embryos in vitro so that their biomass composition matches that of embryos grown in planta; (iii) calculating the rates of substrate consumption by embryos; iv) determining the efficiency at which carbon is converted into biomass; and (v) quantifying the percentage of total labeling within the tricarboxylic acid cycle of 13C-labeled embryos. Further labeling results are in process by performing 13C-based metabolic flux analysis, an approach that will quantify rates of intermediate product formation in the rest of the embryo central metabolism and identify the limiting steps in fatty acid production.Ohio State University Start-Up FundsAcademic Major: Biochemistr
13C labeling of the tricarboxylic acid cycle and carbon conversion efficiency in lesquerella (Physaria fendleri) embryos
Lesquerella (Physaria fendleri) is a Brassicaceae that produces a valuable class of compounds in its embryos called hydroxy fatty acids. These fatty acids are used widely in industry to produce cosmetics, coatings, greases, plastics, paints, and biofuel, among others. The current source of hydroxy fatty acids is ricinoleic acid from the castor plant (Ricinus communis), which also produces the highly toxic compound ricin that has eliminated castor plant cultivation in the United States. Lesquerella produces lesquerolic acid, a hydroxy fatty acid with only two additional carbons as compared to ricinoleic acid, which therefore performs in a chemically similar manner. Since it is non-toxic and already grows in the wild in the southwest US as a winter annual that will not compete with food crops, lesquerella could serve as a suitable alternative to castor oil. However to become economically viable, lesquerella first must be engineered to produce more of these fatty acids to meet demands.Ohio State University Start-Up FundsNo embargoAcademic Major: Biochemistr
Was 2015 the Summer of the Shark? Evidence from the Coastal Carolina University Shark Project
Winyah Bay is a 65-km2 estuary in northeast South Carolina and is considered essential habitat and nursery ground for several shark species of the western North Atlantic. As a result of a number of shark bites/attacks during the summer of 2015, many concluded there was higher abundance of sharks than in previous years. The objective of this study was to test this hypothesis using surveys of shark populations from Winyah Bay in the summer of 2015, and comparing the diversity and abundance of sharks from this survey to those of previous years from the same survey. From July to August in 2002-2006, 2013, and 2015, 169 bottom longlines (16/0 and 12/0 hooks) were set in Winyah Bay. A total of 243 sharks representing 11 species were captured in Winyah Bay. The sandbar shark (Carcharhinus plumbeus), finetooth shark (Carcharhinus isodon), blacktip shark (Carcharhinus limbatus) and Atlantic sharpnose shark (Rhizoprionodon terraenovae) were the most abundant species caught. The average catch per unit effort (CPUE) for all sharks caught in Winyah Bay (1.306, 1.538, 1.706, 1.077, 1.375, 1.545, 1.846, for the periods above) was not significantly different among any of the study years (F = 0.432, p \u3e 0.05, df = 132). However, the proportion of longlines that caught at least one shark (0.722, 0.385, 0.765, 0.538, 0.5, 0.727, and 1.0, for the periods above) was the highest in 2015. Bull sharks accounted for 16.7% of the 2015 total, and the most caught in the period examined for this paper. The prevalence of bull sharks and larger sharks, as well as a high longline index (1.0) could explain the increase in human-shark interactions and could be due to increased water temperatures, the lack of rainfall, or other factors
A randomized trial in a massive online open course shows people don't know what a statistically significant relationship looks like, but they can learn
Scatterplots are the most common way for statisticians, scientists, and the
public to visually detect relationships between measured variables. At the same
time, and despite widely publicized controversy, P-values remain the most
commonly used measure to statistically justify relationships identified between
variables. Here we measure the ability to detect statistically significant
relationships from scatterplots in a randomized trial of 2,039 students in a
statistics massive open online course (MOOC). Each subject was shown a random
set of scatterplots and asked to visually determine if the underlying
relationships were statistically significant at the P < 0.05 level. Subjects
correctly classified only 47.4% (95% CI: 45.1%-49.7%) of statistically
significant relationships, and 74.6% (95% CI: 72.5%-76.6%) of non-significant
relationships. Adding visual aids such as a best fit line or scatterplot smooth
increased the probability a relationship was called significant, regardless of
whether the relationship was actually significant. Classification of
statistically significant relationships improved on repeat attempts of the
survey, although classification of non-significant relationships did not. Our
results suggest: (1) that evidence-based data analysis can be used to identify
weaknesses in theoretical procedures in the hands of average users, (2) data
analysts can be trained to improve detection of statistically significant
results with practice, but (3) data analysts have incorrect intuition about
what statistically significant relationships look like, particularly for small
effects. We have built a web tool for people to compare scatterplots with their
corresponding p-values which is available here:
http://glimmer.rstudio.com/afisher/EDA/.Comment: 7 pages, including 2 figures and 1 tabl
Factors Driving Sugar Cane Production in the Kingdom of Eswatini
Sugar cane is the largest industry in Eswatini with 16 percent of the total workforce working directly or indirectly in the sugar industry. Like all agricultural industries the sugar industry in Eswatini is heavily dependent on an abundant labor supply and climatic conditions. Labor efficiency and abundance is a defining factor of food security and profitability in Eswatini, having one of the highest national HIV/AIDS rates in the world. Small-scale sugar cane producers are often the hardest hit by HIV/AIDS as they traditionally rely on family labor more than hired labor. The 2016 Eswatini Vulnerability Assessment Report indicated that over half of the population in Eswatini required livelihood support, mainly in the form of food aid due to the ongoing El Niño drought. Droughts and variable weather patterns will continue to increase in frequency and magnitude globally. The implication for Eswatini is rain-fed agriculture yields could fall by up to 50 percent by 2020, threatening the livelihoods of the rural poor, a majority of whom earn their living through subsistence agriculture.
This study set out to model the effect of farm size on producer revenue in Eswatini using field-level data from 454 individual sugar cane producers from 2004-2015, coupled with location specific climatic data. Given the lack of extension services throughout Africa, one fear is that large producers may have an inherent advantage in that they can afford crop consultants, higher levels of mechanization and inputs such as inorganic fertilizer. Further, smaller farms may be hit harder by the HIV/AIDS epidemic in Eswatini. Second, given the unprecedented drought of the last decade this study estimates the effects of extreme temperatures and drought on yield and sucrose percentage, which are the drivers of revenue. This study is only one part of a larger effort to develop sustainable sugar cane production in Eswatini. Continued observation of the interaction between increasingly variable weather conditions and sugar cane production outcomes will allow refinement and enhancement of this study and agricultural policy makers in Eswatini with
important direction for sustaining production and enhancing livelihoods of the poorest of the poor in an increasingly hot future
Numerical Uncertainty Quantification for Radiation Analysis Tools
Recently a new emphasis has been placed on engineering applications of space radiation analyses and thus a systematic effort of Verification, Validation and Uncertainty Quantification (VV&UQ) of the tools commonly used for radiation analysis for vehicle design and mission planning has begun. There are two sources of uncertainty in geometric discretization addressed in this paper that need to be quantified in order to understand the total uncertainty in estimating space radiation exposures. One source of uncertainty is in ray tracing, as the number of rays increase the associated uncertainty decreases, but the computational expense increases. Thus, a cost benefit analysis optimizing computational time versus uncertainty is needed and is addressed in this paper. The second source of uncertainty results from the interpolation over the dose vs. depth curves that is needed to determine the radiation exposure. The question, then, is what is the number of thicknesses that is needed to get an accurate result. So convergence testing is performed to quantify the uncertainty associated with interpolating over different shield thickness spatial grids
OTTERTHON
Promote and spread awareness about the families by advertising Otterbein’s 2016 dance marathon, OTTERTHON, by spreading awareness among the campus and Westerville community. To increase participation through community engagement; more specifically, to involve Westerville youth organizations with the children receiving care from Nationwide Children’s Hospital. We performed our objectives by advertising on campus and through word of mouth to the community. On campus advertising consisted of posters we designed with each family\u27s and child’s information on it to spread awareness. Community advertising was through word of mouth reaching out to the youth organizations. Following the event, a survey was emailed to every participant and volunteer that registered. Based on the feedback, we can measure our direct impact compared to other PR methods already in use. In 2015 there were 220 participants with a total funding amount of 18,852. In just one year OTTERTHON was able to increase its participation by 60% and funding by 68%! This significant change in percentages indirectly correlates to our success as a group in achieving our mission. Together, we’ve created an easily accessible digital folder, via Google Drive, full of NEW resources (local youth organization contacts, participation survey results, poster design templates, newspaper ad template, State Street banner display application and price estimate, personal evaluation/recommendations) for future use. Our objectives were met by increasing participation and spreading awareness about the families on campus and in the community through advertisement
Anti-Cloaking: The Mathematics of Disguise
Recent developments in cloaking, the ability to selectively bend electromagnetic waves so as to render an object invisible, have been abundant. Based on cloaking principles, we will describe several ways to mathematically disguise objects in the context of electrical impedance imaging. Through the use of a change-of-variables scheme we show how one can make an object appear enlarged, translated, or rotated by surrounding it with a suitable metamaterial, a man-made material that selectively redirects current. Analysis of eigenvectors and eigenvalues, which describe how current flows, follow. We prove that in order to disguise an object, a metamaterial must encompass both the subdomain and its disguised version, and discuss the consequences. Finally, we brie°y explore how electricity is just a springboard to potential applications
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