450 research outputs found
Computation of steady and unsteady quasi-one-dimensional viscous/inviscid interacting internal flows at subsonic, transonic, and supersonic Mach numbers
Computations of viscous-inviscid interacting internal flowfields are presented for steady and unsteady quasi-one-dimensional (Q1D) test cases. The unsteady Q1D Euler equations are coupled with integral boundary-layer equations for unsteady, two-dimensional (planar or axisymmetric), turbulent flow over impermeable, adiabatic walls. The coupling methodology differs from that used in most techniques reported previously in that the above mentioned equation sets are written as a complete system and solved simultaneously; that is, the coupling is carried out directly through the equations as opposed to coupling the solutions of the different equation sets. Solutions to the coupled system of equations are obtained using both explicit and implicit numerical schemes for steady subsonic, steady transonic, and both steady and unsteady supersonic internal flowfields. Computed solutions are compared with measurements as well as Navier-Stokes and inverse boundary-layer methods. An analysis of the eigenvalues of the coefficient matrix associated with the quasi-linear form of the coupled system of equations indicates the presence of complex eigenvalues for certain flow conditions. It is concluded that although reasonable solutions can be obtained numerically, these complex eigenvalues contribute to the overall difficulty in obtaining numerical solutions to the coupled system of equations
Comparison of Destructive Wind Forces of Hurricane Irma and Other Hurricanes Impacting NASA Kennedy Space Center, 2004-2017
Hurricane Irma produced sustained hurricane force winds (lowest altitude occurrence at 54-ft) resulting in facility damage at Kennedy Space Center (KSC) on September 10-11, 2017. Irma's large destructive wind footprint also caused significant wind damage across the adjacent communities within Brevard County. Wind damage was augmented by frequent gusts of higher magnitude, along with several embedded tornadoes. Hurricanes have previously impacted and produced significant wind damage to infrastructure at KSC as a result of kinetic energy dissipated, in part, through contact with man-made structures. This paper is intended to provide information specific to the destructive force of Hurricane Irma's sustained winds and previous hurricanes of 2004, 2005 and 2016 as calculated from sustained 10 meters per second wind speeds measured from wind towers at KSC for the onset and cessation of destructive forces. Other factors such as pre-existing condition of impacted infrastructure, upstream structures causing turbulent wind patterns, and associated severe convective weather, are contributing factors but are not analyzed here
From Burdens To Benefits: The Societal Impact Of PDL-Enriched, Efficacy-Enhanced Educators
Societies continue to absorb increased burdens in cost for helping citizens unable to achieve at optimal levels. Building on past research, we project educational benefits to offset current societal burdens through enhanced educator capabilities. Studies reviewed show participation in a high-impact professional development and learning solution resulted in improved student performance and reduced dropout rates, reduced disciplinary rates and increased rates for college-bound, along with lower teacher turnover. Computations show that generalization of such impacts should trade societal burdens for benefits at between 6.9 billion within the first year. Cumulatively within 20 years the burdens converted to benefits are projected to exceed $85 billion. Enhanced educator capabilities will substantively reduce needs and costs for societal programs, replaced with tangible benefits to all
Evaluation of two nutrient input methods of HSPF: monthly data block and manual time series
Proceedings of the Seventh International Conference on Hydroscience and Engineering, Philadelphia, PA, September 2006. http://hdl.handle.net/1860/732Use of AGCHEM modules within Hydrological Simulation Program Fortran (HSPF) requires extensive efforts of time series data preparation. In this research, two nutrient input methods, Monthly Data Block and Manual Time Series, were compared and evaluated with a developed St. Louis Bay watershed water quality model. The results indicated that HSPF responded to nutrient input very well and there was much difference in the generated nutrient loadings between these two methods. The Monthly Data Block method is easier to use but it misrepresents nutrient distribution, cannot preserve intended mass balance, and cannot simulate field fertilization practice. Monthly Data Block approach is suitable to provide nutrient inputs from atmospheric deposition. Manual Time Series method is more accurate and flexible to input nutrient from any sources, but is very time-consuming, especially for long time simulation. The users should understand the characteristics of model functions to ensure the correct input of boundary loading since correct input of nutrient boundary loadings has strong impacts on in-stream nutrient modeling
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Ambulatory measurement of knee motion and physical activity: preliminary evaluation of a smart activity monitor
BACKGROUND: There is currently a paucity of devices available for continuous, long-term monitoring of human joint motion. Non-invasive, inexpensive devices capable of recording human activity and joint motion have many applications for medical research. Such a device could be used to quantify range of motion outside the gait laboratory. The purpose of this study was to test the accuracy of the modified Intelligent Device for Energy Expenditure and Activity (IDEEA) in measuring knee flexion angles, to detect different physical activities, and to quantify how often healthy subjects use deep knee flexion in the ambulatory setting. METHODS: We compared Biomotion Laboratory (BML) "gold standard" data to simultaneous IDEEA measures of knee motion and gait, step up/down, and stair descent in 5 healthy subjects. In addition, we used a series of choreographed physical activities outside the BML to confirm the IDEEA's ability to accurately measure 7 commonly-performed physical activities. Subjects then continued data collection during ordinary activities outside the gait laboratory. RESULTS: Pooled correlations between the BML and IDEEA knee flexion angles were .97 +/- .03 for step up/down, .98 +/- .02 for stair descent, and .98 +/- .01 for gait. In the BML protocol, the IDEEA accurately identified gait, but was less accurate in identifying step up/down and stair descent. During sampling outside the BML, the IDEEA accurately detected walking, running, stair ascent, stair descent, standing, lying, and sitting. On average, subjects flexed their knees >120° for 0.17% of their data collection periods outside the BML. CONCLUSION: The modified IDEEA system is a useful clinical tool for evaluating knee motion and multiple physical activities in the ambulatory setting. These five healthy subjects rarely flexed their knees >120°
Discovery and genotyping of structural variation from long-read haploid genome sequence data
In an effort to more fully understand the full spectrum of human genetic variation, we generated deep single-molecule, real-time (SMRT) sequencing data from two haploid human genomes. By using an assembly-based approach (SMRT-SV), we systematically assessed each genome independently for structural variants (SVs) and indels resolving the sequence structure of 461,553 genetic variants from 2 bp to 28 kbp in length. We find that >89% of these variants have been missed as part of analysis of the 1000 Genomes Project even after adjusting for more common variants (MAF > 1%). We estimate that this theoretical human diploid differs by as much as ∼16 Mbp with respect to the human reference, with long-read sequencing data providing a fivefold increase in sensitivity for genetic variants ranging in size from 7 bp to 1 kbp compared with short-read sequence data. Although a large fraction of genetic variants were not detected by short-read approaches, once the alternate allele is sequence-resolved, we show that 61% of SVs can be genotyped in short-read sequence data sets with high accuracy. Uncoupling discovery from genotyping thus allows for the majority of this missed common variation to be genotyped in the human population. Interestingly, when we repeat SV detection on a pseudodiploid genome constructed in silico by merging the two haploids, we find that ∼59% of the heterozygous SVs are no longer detected by SMRT-SV. These results indicate that haploid resolution of long-read sequencing data will significantly increase sensitivity of SV detection.</jats:p
Adaptive Water Resource Management for Taste and Odor Control for the Anderson Regional Joint Water System
2016 South Carolina Water Resources Conference
South Carolina Water Resources at a Crossroads: Response, Readiness and Recover
Evolution and rapid spread of a reassortant A(H3N2) virus that predominated the 2017-2018 influenza season
The 2017-2018 North American influenza season caused more hospitalizations and deaths than any year since the 2009 H1N1 pandemic. The majority of recorded influenza infections were caused by A(H3N2) viruses, with most of the virus's North American diversity falling into the A2 clade. Within A2, we observe a subclade which we call A2/re that rose to comprise almost 70 per cent of A(H3N2) viruses circulating in North America by early 2018. Unlike most fast-growing clades, however, A2/re contains no amino acid substitutions in the hemagglutinin (HA) segment. Moreover, hemagglutination inhibition assays did not suggest substantial antigenic differences between A2/re viruses and viruses sampled during the 2016-2017 season. Rather, we observe that the A2/re clade was the result of a reassortment event that occurred in late 2016 or early 2017 and involved the combination of the HA and PB1 segments of an A2 virus with neuraminidase (NA) and other segmentsa virus from the clade A1b. The success of this clade shows the need for antigenic analysis that targets NA in addition to HA. Our results illustrate the potential for non-HA drivers of viral success and necessitate the need for more thorough tracking of full viral genomes to better understand the dynamics of influenza epidemics
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