952 research outputs found
Comparison of ALE and SPH Simulations of Vertical Drop Tests of a Composite Fuselage Section into Water
Simulation of multi-terrain impact has been identified as an important research area for improved prediction of rotorcraft crashworthiness within the NASA Subsonic Rotary Wing Aeronautics Program on Rotorcraft Crashworthiness. As part of this effort, two vertical drop tests were conducted of a 5-ft-diameter composite fuselage section into water. For the first test, the fuselage section was impacted in a baseline configuration without energy absorbers. For the second test, the fuselage section was retrofitted with a composite honeycomb energy absorber. Both tests were conducted at a nominal velocity of 25-ft/s. A detailed finite element model was developed to represent each test article and water impact was simulated using both Arbitrary Lagrangian Eulerian (ALE) and Smooth Particle Hydrodynamics (SPH) approaches in LS-DYNA, a nonlinear, explicit transient dynamic finite element code. Analytical predictions were correlated with experimental data for both test configurations. In addition, studies were performed to evaluate the influence of mesh density on test-analysis correlation
Vertical Drop Testing and Analysis of the WASP Helicopter Skid Gear
Human occupant modeling and injury risk assessment have been identified as areas of research for improved prediction of rotorcraft crashworthiness within the NASA Aeronautics Program's Subsonic Rotary Wing Project. As part of this effort, an experimental program was conducted to assess the impact performance of a skid gear for use on the WASP kit-built helicopter, which is marketed by HeloWerks, Inc. of Hampton, Virginia. Test data from a drop test at an impact velocity of 8.4 feet-per-second were used to assess a finite element model of the skid gear test article. This assessment included human occupant analytic models developed for execution in LS-DYNA. The test article consisted of an aluminum skid gear mounted beneath a steel plate. A seating platform was attached to the upper surface of the steel plate, and two 95th percentile Hybrid III male Aerospace Anthropomorphic Test Devices (ATDs) were seated on the platform and secured using a four-point restraint system. The goal of the test-analysis correlation is to further the understanding of LS-DYNA ATD occupant models and responses in the vertical (or spinal) direction. By correlating human occupant experimental test data for a purely vertical impact with the LS-DYNA occupant responses, improved confidence in the use of these tools and better understanding of the limitations of the automotive-based occupant models for aerospace application can begin to be developed
Educators Voices from Integrated Writing and Problem Solving Common Core Workshop
This article provides an opportunity to discuss and examine information gathered during a focus group of K-12 educators involved in an integrated writing and problem solving workshop. Findings demonstrate that some educators are frustrated by the culture of testing versus the culture of learning that exist as a result of the Common Core Standards implementation. Educators are eager to learn and implement new ways of learning in order to promote deeper learning and critical thinking skills. Strategies and recommendations for providing support and resources for educators to meet the expectations to prepare students to be college and career ready are discussed
Overview of the NASA Subsonic Rotary Wing Aeronautics Research Program in Rotorcraft Crashworthiness
This paper provides an overview of rotorcraft crashworthiness research being conducted at NASA Langley Research Center under sponsorship of the Subsonic Rotary Wing (SRW) Aeronautics Program. The research is focused in two areas: development of an externally deployable energy attenuating concept and improved prediction of rotorcraft crashworthiness. The deployable energy absorber (DEA) is a composite honeycomb structure, with a unique flexible hinge design that allows the honeycomb to be packaged and remain flat until needed for deployment. The capabilities of the DEA have been demonstrated through component crush tests and vertical drop tests of a retrofitted fuselage section onto different surfaces or terrain. The research on improved prediction of rotorcraft crashworthiness is focused in several areas including simulating occupant responses and injury risk assessment, predicting multi-terrain impact, and utilizing probabilistic analysis methods. A final task is to perform a system-integrated simulation of a full-scale helicopter crash test onto a rigid surface. A brief description of each research task is provided along with a summary of recent accomplishments
Community Engagement: Using Feedback Loops to Empower Residents and Influence Systemic Change in Culturally Diverse Communities
A multi-faceted approach to community engagement includes the need to involve the community members in the design, implementation and feedback of any program, services, or supports provided. Intentional participatory engagement of residents also requires shared responsibility for workload, shared recognition of achievement, thoughtful communication, engagement in robust discussions taking care not to internalize conversations as personal affronts and holding close the rules of effective decision making (Toms & Burgess, 2014). Implementing a feedback loop process can be used as a tool to foster intentional resident engagement. The findings presented in this article are from a case study of a neighborhood that implemented a feedback loop process. Analysis of data indicate that while transportation, housing, and places for people to safely be outside are real community concerns, acts of nature and choices made by city government also directly impact the quality of life of the residents in this community. The need for purposeful channels of communication to be established among residents, between neighborhood action groups, and city government is evident. Leveraging relationships with community partners to establish trust and organizational understanding of culture within community socio-economic context, along with the multiple layers of community engagement is discussed
Community Engagement: Using Feedback Loops to Empower Residents and Influence Systemic Change in Culturally Diverse Communities
A multi-faceted approach to community engagement includes the need to involve the community members in the design, implementation and feedback of any program, services, or supports provided. Intentional participatory engagement of residents also requires shared responsibility for workload, shared recognition of achievement, thoughtful communication, engagement in robust discussions taking care not to internalize conversations as personal affronts and holding close the rules of effective decision making (Toms & Burgess, 2014). Implementing a feedback loop process can be used as a tool to foster intentional resident engagement. The findings presented in this article are from a case study of a neighborhood that implemented a feedback loop process. Analysis of data indicate that while transportation, housing, and places for people to safely be outside are real community concerns, acts of nature and choices made by city government also directly impact the quality of life of the residents in this community. The need for purposeful channels of communication to be established among residents, between neighborhood action groups, and city government is evident. Leveraging relationships with community partners to establish trust and organizational understanding of culture within community socio-economic context, along with the multiple layers of community engagement is discussed
Pathways to Institutional Transformation at HBCUs: Recommendations from HBCU Black Women STEM Faculty
Black women STEM faculty at historically Black colleges and universities (HBCUs) experience many barriers to promotion, tenure, and the attainment of leadership positions. Institutional transformation is essential in addressing these inequities. However, there is a lack of literature that addresses the pathways for institutional transformation at HBCUs. The purpose of this paper is to share Black women STEM faculty from HBCUs recommendations for institutional transformation. Inter-views were conducted with fifteen Black women STEM faculty at HBCUs. Find-ings revealed several themes including the need for: (1) institutional accountability and oversight, (2) investment in the representation of Black women in faculty and administration ranks, (3) leadership training and opportunities, (4) increased support for research scholarship, (5) opportunities for internal and external mentorship on scholarship and tenure, and (6) expanding student support services. Based on participants’ reflections recommendations are offered to facilitate institutional transformation that supports the advancement of Black women STEM faculty at HBCUs
Aligning Tenure and Promotion Procedures for Community-University Engagement: Dialogue for Action
Palliative care needs in patients hospitalized with heart failure (PCHF) study: rationale and design
Abstract Aims The primary aim of this study is to provide data to inform the design of a randomized controlled clinical trial (RCT) of a palliative care (PC) intervention in heart failure (HF). We will identify an appropriate study population with a high prevalence of PC needs defined using quantifiable measures. We will also identify which components a specific and targeted PC intervention in HF should include and attempt to define the most relevant trial outcomes. Methods An unselected, prospective, near-consecutive, cohort of patients admitted to hospital with acute decompensated HF will be enrolled over a 2-year period. All potential participants will be screened using B-type natriuretic peptide and echocardiography, and all those enrolled will be extensively characterized in terms of their HF status, comorbidity, and PC needs. Quantitative assessment of PC needs will include evaluation of general and disease-specific quality of life, mood, symptom burden, caregiver burden, and end of life care. Inpatient assessments will be performed and after discharge outpatient assessments will be carried out every 4 months for up to 2.5 years. Participants will be followed up for a minimum of 1 year for hospital admissions, and place and cause of death. Methods for identifying patients with HF with PC needs will be evaluated, and estimates of healthcare utilisation performed. Conclusion By assessing the prevalence of these needs, describing how these needs change over time, and evaluating how best PC needs can be identified, we will provide the foundation for designing an RCT of a PC intervention in HF
Fluorescent amplified fragment length polymorphism analysis of Norwegian Bacillus cereus and Bacillus thuringiensis soil isolates
We examined 154 Norwegian B. cereus and B. thuringiensis soil isolates (collected from five different locations), 8 B. cereus and 2 B. thuringiensis reference strains, and 2 Bacillus anthracis strains by using fluorescent amplified fragment length polymorphism (AFLP). We employed a novel fragment identification approach based on a hierarchical agglomerative clustering routine that identifies fragments in an automated fashion. No method is free of error, and we identified the major sources so that experiments can be designed to minimize its effect. Phylogenetic analysis of the fluorescent AFLP results reveals five genetic groups in these group 1 bacilli. The ATCC reference strains were restricted to two of the genetic groups, clearly not representative of the diversity in these bacteria. Both B. anthracis strains analyzed were closely related and affiliated with a B. cereus milk isolate (ATCC 4342) and a B. cereus human pathogenic strain (periodontitis). Across the entire study, pathogenic strains, including B. anthracis, were more closely related to one another than to the environmental isolates. Eight strains representing the five distinct phylogenetic clusters were further analyzed by comparison of their 16S rRNA gene sequences to confirm the phylogenetic status of these groups. This analysis was consistent with the AFLP analysis, although of much lower resolution. The innovation of automated genotype analysis by using a replicated and statistical approach to fragment identification will allow very large sample analyses in the future
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