1,846 research outputs found

    Systems Engineering Cost/Risk Analysis Capability Roadmap Progress Review

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    A viewgraph presentation on the cost/risk analysis capability of systems engineering is shown

    A Large Sample Comparison of Grade Based Student Learning Outcomes in Online vs. Face-to-Face Courses

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    Comparisons of grade based learning outcomes between online and face-to-face course formats have become essential because the number of online courses, online programs and institutional student enrollments have seen rapid growth in recent years. Overall, online education is largely viewed by education professionals as being equivalent to instruction conducted face-to-face. However, the research investigating student performance in online versus face-to-face courses has been mixed and is often hampered by small samples or a lack of demographic and academic controls. This study utilizes a dataset that includes over 5,000 courses taught by over 100 faculty members over a period of ten academic terms at a large, public, four-year university. The unique scale of the dataset facilitates macro level understanding of course formats at an institutional level. Multiple regression was used to account for student demographic and academic corollaries--factors known to bias course format selection and grade based outcomes--to generate a robust test for differences in grade based learning outcomes that could be attributed to course format. The final model identified a statistical difference between course formats that translated into a negligible difference of less than 0.07 GPA points on a 4 point scale. The primary influence on individual course grades was student GPA. Interestingly, a model based interaction between course type and student GPA indicated a cumulative effect whereby students with higher GPAs will perform even better in online courses (or alternatively, struggling students perform worse when taking courses in an online format compared to a face-to-face format). These results indicate that, given the large scale university level, multi course, and student framework of the current study, there is little to no difference in grade based student performance between instructional modes for courses where both modes are applicable

    Variation in Student Perceptions of Higher Education Course Quality and Difficulty as a Result of Widespread Implementation of Online Education During the COVID-19 Pandemic

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    The onset of the COVID-19 global pandemic affected higher education in a myriad of ways. One of the most notable effects however was the rapid and sudden transition of nearly all courses at most institutions to an online environment. And while there are a growing number of courses offered online already, this transition to nearly 100% remote education presented numerous challenges for instructors and students of face-to-face and hybrid style courses. Since student perceptions are closely tied to recruitment and retention, it is important to know if there are differences in student perceptions present in the way different courses are taught. This study extends the work of other authors that have investigated student perceptions by looking specifically at how the COVID-19 pandemic may have changed student views of course difficulty and quality both overall and across discipline or institution categories. Course evaluations from 837 courses from 191 different schools archived on RateMyProfessors.com were used in a general linear model where a statistically significant overall decline of 6% in perceived course difficulty and 4% decline in perceived quality was detected. In addition to calculating this mean decrease, courses were also categorized on the basis of academic discipline (Business, Engineering and Mathematics, Humanities, Natural Sciences, Social Sciences), institution type (2-Year, 4-Year), and whether instructors had previous experience teaching online courses (No, Yes) to determine any variation in differences that may have appeared as a result of more nuanced details in course type or delivery. Most notably, declines in course difficulty were slightly more apparent with instructors that had no previous online teaching experience. No other discipline, institution type, or teaching experience interactions were detected with either difficulty or quality variation. These data suggest that there were very real changes in perceived quality and difficulty but that these changes were largely universal irrespective of discipline, institution type, or prior experience teaching online (with exception of course difficulty)

    Multifractality, Interactivity, and the Adaptive Capacity of the Human Movement System: A Perspective for Advancing the Conceptual Basis of Neurologic Physical Therapy

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    Background and Purpose: Physical therapists seek to optimize movement as a means of reducing disability and improving health. The short-term effects of interventions designed to optimize movement ultimately are intended to be adapted for use across various future patterns of behavior, in potentially unpredictable ways, with varying frequency, and in the context of multiple tasks and environmental conditions. In this perspective article, we review and discuss the implications of recent evidence that optimal movement variability, which previously had been associated with adaptable motor behavior, contains a specific complex nonlinear feature known as “multifractality.” Summary of Key Points: Multifractal movement fluctuation patterns reflect robust physiologic interactivity occurring within the movement system across multiple time scales. Such patterns provide conceptual support for the idea that patterns of motor behavior occurring in the moment are inextricably linked in complex, physiologic ways to patterns of motor behavior occurring over much longer periods. The human movement system appears to be particularly tuned to multifractal fluctuation patterns and exhibits the ability to reorganize its output in response to external stimulation embedded with multifractal features. Recommendations for Clinical Practice: As a fundamental feature of human movement, multifractality opens new avenues for conceptualizing the link between physiologic interactivity and adaptive capacity. Preliminary evidence supporting the positive influence of multifractal rhythmic auditory stimulation on the gait patterns of individuals with Parkinson disease is used to illustrate how physical therapy interventions might be devised to specifically target the adaptive capacity of the human movement system. Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, https://links.lww.com/JNPT/A183)

    NASA Langley Systems Analysis & Concepts Directorate Technology Assessment/Portfolio Analysis

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    Systems analysis develops and documents candidate mission and architectures, associated system concepts, enabling capabilities and investment strategies to achieve NASA s strategic objectives. The technology assessment process connects the mission and architectures to the investment strategies. In order to successfully implement a technology assessment, there is a need to collect, manipulate, analyze, document, and disseminate technology-related information. Information must be collected and organized on the wide variety of potentially applicable technologies, including: previous research results, key technical parameters and characteristics, technology readiness levels, relationships to other technologies, costs, and potential barriers and risks. This information must be manipulated to facilitate planning and documentation. An assessment is included of the programmatic and technical risks associated with each technology task as well as potential risk mitigation plans. Risks are assessed and tracked in terms of likelihood of the risk occurring and consequences of the risk if it does occur. The risk assessments take into account cost, schedule, and technical risk dimensions. Assessment data must be simplified for presentation to decision makers. The Systems Analysis and Concepts Directorate (SACD) at NASA Langley Research Center has a wealth of experience in performing Technology Assessment and Portfolio Analysis as this has been a business line since 1978

    Characterization of an autotrophic sulfide-oxidizing marine Arcobacter sp. that produces filamentous sulfur

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    Author Posting. © American Society for Microbiology, 2002. This article is posted here by permission of American Society for Microbiology for personal use, not for redistribution. The definitive version was published in Applied and Environmental Microbiology 68 (2002): 316-325, doi:10.1128/AEM.68.1.316-325.2002.A coastal marine sulfide-oxidizing autotrophic bacterium produces hydrophilic filamentous sulfur as a novel metabolic end product. Phylogenetic analysis placed the organism in the genus Arcobacter in the epsilon subdivision of the Proteobacteria. This motile vibrioid organism can be considered difficult to grow, preferring to grow under microaerophilic conditions in flowing systems in which a sulfide-oxygen gradient has been established. Purified cell cultures were maintained by using this approach. Essentially all 4',6-diamidino-2-phenylindole dihydrochloride-stained cells in a flowing reactor system hybridized with Arcobacter-specific probes as well as with a probe specific for the sequence obtained from reactor-grown cells. The proposed provisional name for the coastal isolate is "Candidatus Arcobacter sulfidicus." For cells cultured in a flowing reactor system, the sulfide optimum was higher than and the CO2 fixation activity was as high as or higher than those reported for other sulfur oxidizers, such as Thiomicrospira spp. Cells associated with filamentous sulfur material demonstrated nitrogen fixation capability. No ribulose 1,5-bisphosphate carboxylase/oxygenase could be detected on the basis of radioisotopic activity or by Western blotting techniques, suggesting an alternative pathway of CO2 fixation. The process of microbial filamentous sulfur formation has been documented in a number of marine environments where both sulfide and oxygen are available. Filamentous sulfur formation by "Candidatus Arcobacter sulfidicus" or similar strains may be an ecologically important process, contributing significantly to primary production in such environments.This work was supported by National Science Foundation grant IBN-9630054

    Effect of Charging Electron Exposure on 1064nm Transmission through Bare Sapphire Optics and SiO2 over HfO2 AR-coated Sapphire Optics

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    Experiments measuring the effect of electron exposure on 1064nm transmission for optical sapphire were conducted. Detailed before and after inspections did not identify any resulting Litchenburg patterns. Pre- and post-exposure 1064nm transmission measurements are compared

    Habitat Demonstration Unit (HDU) Vertical Cylinder Habitat

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    NASA's Constellation Architecture Team defined an outpost scenario optimized for intensive mobility that uses small, highly mobile pressurized rovers supported by portable habitat modules that can be carried between locations of interest on the lunar surface. A compact vertical cylinder characterizes the habitat concept, where the large diameter maximizes usable flat floor area optimized for a gravity environment and allows for efficient internal layout. The module was sized to fit into payload fairings for the Constellation Ares V launch vehicle, and optimized for surface transport carried by the All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) mobility system. Launch and other loads are carried through the barrel to a top and bottom truss that interfaces with a structural support unit (SSU). The SSU contains self-leveling feet and docking interfaces for Tri-ATHLETE grasping and heavy lift. A pressurized module needed to be created that was appropriate for the lunar environment, could be easily relocated to new locations, and could be docked together in multiples for expanding pressurized volume in a lunar outpost. It was determined that horizontally oriented pressure vessels did not optimize floor area, which takes advantage of the gravity vector for full use. Hybrid hard-inflatable habitats added an unproven degree of complexity that may eventually be worked out. Other versions of vertically oriented pressure vessels were either too big, bulky, or did not optimize floor area. The purpose of the HDU vertical habitat module is to provide pressurized units that can be docked together in a modular way for lunar outpost pressurized volume expansion, and allow for other vehicles, rovers, and modules to be attached to the outpost to allow for IVA (intra-vehicular activity) transfer between them. The module is a vertically oriented cylinder with a large radius to allow for maximal floor area and use of volume. The modular, 5- m-diameter HDU vertical habitat module consists of a 2-m-high barrel with 0.6-mhigh end domes forming the 56-cubicmeter pressure vessel, and a 19-squaremeter floor area. The module has up to four docking ports located orthogonally from each other around the perimeter, and up to one docking port each on the top or bottom end domes. In addition, the module has mounting trusses top and bottom for equipment, and to allow docking with the ATHLETE mobility system. Novel or unique features of the HDU vertical habitat module include the nodelike function with multiple pressure hatches for docking with other versions of itself and other modules and vehicles; the capacity to be carried by an ATHLETE mobility system; and the ability to attach inflatable 'attic' domes to the top for additional pressurized volume

    The Grizzly, December 9, 2010

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    UC Performing Arts to Come Together • Conflux Festival Allows for Innovative Technology • UCompost Continues to Help Create Change on Campus • Breakthroughs in Science Bring New Insight • UC Students Embrace Gaming and Some Late Night Fun • Clarifying the Calamity of Clamer Hall Renovations • Local Holiday Light Displays Worth Checking Out • Banning of Four Loko May Not Bring Change • Internship Profile: Inki Hong • Opinion: Korean War Could Cause International Problems; Review of the Diversity Monologues • Men\u27s Basketball Looks to Grow Throughout Season • Indoor Track and Field Begins Seasonhttps://digitalcommons.ursinus.edu/grizzlynews/1826/thumbnail.jp

    Rationale and design for SHAREHD: a quality improvement collaborative to scale up Shared Haemodialysis Care for patients on centre based haemodialysis.

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    BACKGROUND: The study objective is to assess the effectiveness and economic impact of a structured programme to support patient involvement in centre-based haemodialysis and to understand what works for whom in what circumstances and why. It implements a program of Shared Haemodialysis Care (SHC) that aims to improve experience and outcomes for those who are treated with centre-based haemodialysis, and give more patients the confidence to dialyse independently both at centres and at home. METHODS/DESIGN: The 24 month mixed methods cohort evaluation of 600 prevalent centre based HD patients is nested within a 30 month quality improvement program that aims to scale up SHC at 12 dialysis centres across England. SHC describes an intervention where patients who receive centre-based haemodialysis are given the opportunity to learn, engage with and undertake tasks associated with their treatment. Following a 6-month set up period, a phased implementation programme is initiated across 12 dialysis units using a randomised stepped wedge design with 6 centres participating in each of 2 steps, each lasting 6 months. The intervention utilises quality improvement methodologies involving rapid tests of change to determine the most appropriate mechanisms for implementation in the context of a learning collaborative. Running parallel with the stepped wedge intervention is a mixed methods cohort evaluation that employs patient questionnaires and interviews, and will link with routinely collected data at the end of the study period. The primary outcome measure is the number of patients performing at least 5 dialysis-related tasks collected using 3 monthly questionnaires. Secondary outcomes measures include: the number of people choosing to perform home haemodialysis or dialyse independently in-centre by the end of the study period; end-user recommendation; home dialysis establishment delay; staff impact and confidence; hospitalisation; infection and health economics. DISCUSSION: The results from this study will provide evidence of impact of SHC, barriers to patient and centre level adoption and inform development of future interventions to support its implementation. TRIAL REGISTRATION: ISRCTN Number: 93999549 , (retrospectively registered 1st May 2017); NIHR Research Portfolio: 31566
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