Preliminary system design study for a digital fly-by-wire flight control system for an F-8C aircraft

The design of a fly-by-wire control system having a mission failure probability of less than one millionth failures per flight hour is examined. Emphasis was placed on developing actuator configurations that would improve the system performance, and consideration of the practical aspects of sensor/computer and computer/actuator interface implementation. Five basic configurations were defined as appropriate candidates for the F-8C research aircraft. Options on the basic configurations were included to cover variations in flight sensors, redundancy levels, data transmission techniques, processor input/output methods, and servo actuator arrangements. The study results can be applied to fly by wire systems for transport aircraft in general and the space shuttle

Atomic oxygen beam source for erosion simulation

A device for the production of low energy (3 to 10 eV) neutral atomic beams for surface modification studies is described that reproduces the flux of atomic oxygen in low Earth orbit. The beam is produced by the acceleration of plasma ions onto a negatively biased plate of high-Z metal; the ions are neutralized and reflected by the surface, retaining some fraction of their incident kinetic energy, forming a beam of atoms. The plasma is generated by a coaxial RF exciter which produces a magnetically-confined (4 kG) plasma column. At the end of the column, ions fall through the sheath to the plate, whose bias relative to the plasma can be varied to adjust the beam energy. The source provides a neutral flux approximately equal to 5 x 10(exp 16)/sq cm at a distance of 9 cm and a fluence approximately equal to 10(exp 20)/sq cm in five hours. The composition and energy of inert gas beams was diagnosed using a mass spectometer/energy analyzer. The energy spectra of the beams demonstrate energies in the range 5 to 15 eV, and qualitatively show expected dependences upon incident and reflecting atom species and potential drop. Samples of carbon film, carbon-based paint, Kapton, mylar, and teflon exposed to atomic O beams show erosion quite similar to that observed in orbit on the space shuttle

Community-Campus Partnerships for Health: Making a Positive Impact

Offers pragmatic insights from diverse community-campus partnerships, service-learning initiatives, and workforce diversity efforts across the country, including communities from the foundation's Community Voices initiative

Cavitation-induced ignition of cryogenic hydrogen-oxygen fluids

The Challenger disaster and purposeful experiments with liquid hydrogen (H2) and oxygen (Ox) tanks demonstrated that cryogenic H2/Ox fluids always self-ignite in the process of their mixing. Here we propose a cavitation-induced self-ignition mechanism that may be realized under these conditions. In one possible scenario, self-ignition is caused by the strong shock waves generated by the collapse of pure Ox vapor bubble near the surface of the Ox liquid that may initiate detonation of the gaseous H2/Ox mixture adjacent to the gas-liquid interface. This effect is further enhanced by H2/Ox combustion inside the collapsing bubble in the presence of admixed H2 gas

LEAH interdisciplinary training program

This article describes the Leadership Education in Adolescent Health (LEAH) interdisciplinary training program in the United States. The Maternal and Child Health Bureau authorized by legislation provides monies to train leaders in adolescent health through a competitive grant process. Currently, seven academic medical centers have funding to provide leadership in adolescent health (LEAH) training in five core disciplines: medicine, nursing, psychology, social work and nutrition. LEAH training programs both ensure high clinical competence in core disciplines serving adolescents and prepare trainees for leadership positions in adolescent health and public health care realms. Together, these programs trained almost 1000 long-term trainees across these five disciplines, and graduates from these programs are working in 45 of the 50 states within the United States. About 90% of these graduates are working with maternal and child/adolescent health populations, and almost all have held leadership positions in the areas of public health, advocacy, public policy, academic medical centers and/or clinical care settings

Study of aircraft in intraurban transportation systems, volume 1

An analysis of an effective short range, high density computer transportation system for intraurban systems is presented. The seven county Detroit, Michigan, metropolitan area, was chosen as the scenario for the analysis. The study consisted of an analysis and forecast of the Detroit market through 1985, a parametric analysis of appropriate short haul aircraft concepts and associated ground systems, and a preliminary overall economic analysis of a simplified total system designed to evaluate the candidate vehicles and select the most promising VTOL and STOL aircraft. Data are also included on the impact of advanced technology on the system, the sensitivity of mission performance to changes in aircraft characteristics and system operations, and identification of key problem areas that may be improved by additional research. The approach, logic, and computer models used are adaptable to other intraurban or interurban areas

Nematicity as a route to a magnetic field-induced spin density wave order; application to the high temperature cuprates

The electronic nematic order characterized by broken rotational symmetry has been suggested to play an important role in the phase diagram of the high temperature cuprates. We study the interplay between the electronic nematic order and a spin density wave order in the presence of a magnetic field. We show that a cooperation of the nematicity and the magnetic field induces a finite coupling between the spin density wave and spin-triplet staggered flux orders. As a consequence of such a coupling, the magnon gap decreases as the magnetic field increases, and it eventually condenses beyond a critical magnetic field leading to a field-induced spin density wave order. Both commensurate and incommensurate orders are studied, and the experimental implications of our findings are discussed.Comment: 5 pages, 3 figure

The iPlant Collaborative: Cyberinfrastructure for Enabling Data to Discovery for the Life Sciences

The iPlant Collaborative provides life science research communities access to comprehensive, scalable, and cohesive computational infrastructure for data management; identity management; collaboration tools; and cloud, high-performance, high-throughput computing. iPlant provides training, learning material, and best practice resources to help all researchers make the best use of their data, expand their computational skill set, and effectively manage their data and computation when working as distributed teams. iPlant's platform permits researchers to easily deposit and share their data and deploy new computational tools and analysis workflows, allowing the broader community to easily use and reuse those data and computational analyses

Activating social change together: A qualitative synthesis of collaborative change research, evaluation and design literature

Researchers, evaluators and designers from an array of academic disciplines and industry sectors are turning to participatory approaches as they seek to understand and address complex social problems. We refer to participatory approaches that collaboratively engage/partner with stakeholders in knowledge creation/problem solving for action/social change outcomes as collaborative change research, evaluation and design (CCRED). We further frame CCRED practitioners by their desire to move beyond knowledge creation for its own sake to implementation of new knowledge as a tool for social change. In March and May of 2018, we conducted a literature search of multiple discipline-specific databases seeking collaborative, change-oriented scholarly publications. The search was limited to include peer-reviewed journal articles, with English language abstracts available, published in the last five years. The search resulted in 526 citations, 236 of which met inclusion criteria. Though the search was limited to English abstracts, all major geographic regions (North America, Europe, Latin America/Caribbean, APAC, Africa and the Middle East) were represented within the results, although many articles did not state a specific region. Of those identified, most studies were located in North America, with the Middle East having only one identified study. We followed a qualitative thematic synthesis process to examine the abstracts of peer-reviewed articles to identify practices that transcend individual disciplines, sectors and contexts to achieve collaborative change. We surveyed the terminology used to describe CCRED, setting, content/topic of study, type of collaboration, and related benefits/outcomes in order to discern the words used to designate collaboration, the frameworks, tools and methods employed, and the presence of action, evaluation or outcomes. Forty-three percent of the reviewed articles fell broadly within the social sciences, followed by 26 percent in education and 25 percent in health/medicine. In terms of participants and/or collaborators in the articles reviewed, the vast majority of the 236 articles (86%) described participants, that is, those who the research was about or from whom data was collected. In contrast to participants, partners/collaborators (n=32; 14%) were individuals or groups who participated in the design or implementation of the collaborative change effort described. In terms of the goal for collaboration and/or for doing the work, the most frequently used terminology related to some aspect of engagement and empowerment. Common descriptors for the work itself were ‘social change’ (n=74; 31%), ‘action’ (n=33; 14%), ‘collaborative or participatory research/practice’ (n=13; 6%), ‘transformation’ (n=13; 6%) and ‘community engagement’ (n=10; 4%). Of the 236 articles that mentioned a specific framework or approach, the three most common were some variation of Participatory Action Research (n=30; 50%), Action Research (n=40; 16.9%) or Community-Based Participatory Research (n=17; 7.2%). Approximately a third of the 236 articles did not mention a specific method or tool in the abstract. The most commonly cited method/tool (n=30; 12.7%) was some variation of an arts-based method followed by interviews (n=18; 7.6%), case study (n=16; 6.7%), or an ethnographic-related method (n=14; 5.9%). While some articles implied action or change, only 14 of the 236 articles (6%) stated a specific action or outcome. Most often, the changes described were: the creation or modification of a model, method, process, framework or protocol (n=9; 4%), quality improvement, policy change and social change (n=8; 3%), or modifications to education/training methods and materials (n=5; 2%). The infrequent use of collaboration as a descriptor of partner engagement, coupled with few reported findings of measurable change, raises questions about the nature of CCRED. It appears that conducting CCRED is as complex an undertaking as the problems that the work is attempting to address