A gyroscope calibration analysis for the Gamma Ray Observatory (GRO)

Current documentation and software do not adequately address the calculation and use of the optimal weight matrices involved in calibrating inertial reference units (IRU). Several facets of the GRO IRU calibration as it relates to the bias and misalignment weighting matrices are investigated. The physical meaning and use of the bias and misalignment weight matrices in IRU calibration are examined. The relation of the weighting and the final biases, misalignments, and their corrections are pursued. Methods for determining reliable, realistic weighting matrices to be used in the GRO IRU calibration (IRUCAL) utility are determined. Possible correlations among observation uncertainties are also explored. For the undetermined case where the maneuvers are insufficient to identify all calibration parameters, the weighting matrices allow as much information as possible to be extracted from the measurements. Finally, applicable simulated flight data are used, incorporating the appropriate calibration maneuvers, to test the weighting matrices in the IRUCAL utility, and examine correlation effects

Summary of Rocketdyne Engine A5 Rocket Based Combined Cycle Testing

Rocketdyne Propulsion and Power (RPP) has completed a highly successful experimental test program of an advanced rocket based combined cycle (RBCC) propulsion system. The test program was conducted as part of the Advanced Reusable Technology program directed by NASA-MSFC to demonstrate technologies for low-cost access to space. Testing was conducted in the new GASL Flight Acceleration Simulation Test (FAST) facility at sea level (Mach 0), Mach 3.0 - 4.0, and vacuum flight conditions. Significant achievements obtained during the test program include 1) demonstration of engine operation in air-augmented rocket mode (AAR), ramjet mode and rocket mode and 2) smooth transition from AAR to ramjet mode operation. Testing in the fourth mode (scramjet) is scheduled for November 1998

Mars mission solar array Semiannual progress report, period ending 31 Dec. 1969

Design and testing of beryllium-structure solar panel for Mars missio

Application of Optimization Techniques to Design of Unconventional Rocket Nozzle Configurations

Several current rocket engine concepts such as the bell-annular tri-propellant engine, and the linear aerospike being proposed for the X-33 require unconventional three dimensional rocket nozzles which must conform to rectangular or sector shaped envelopes to meet integration constraints. These types of nozzles exist outside the current experience database, therefore, the application of efficient design methods for these propulsion concepts is critical to the success of launch vehicle programs. The objective of this work is to optimize several different nozzle configurations, including two- and three-dimensional geometries. Methodology includes coupling computational fluid dynamic (CFD) analysis to genetic algorithms and Taguchi methods as well as implementation of a streamline tracing technique. Results of applications are shown for several geometeries including: three dimensional thruster nozzles with round or super elliptic throats and rectangualar exits, two- and three-dimensional thrusters installed within a bell nozzle, and three dimensional thrusters with round throats and sector shaped exits. Due to the novel designs considered for this study, there is little experience which can be used to guide the effort and limit the design space. With a nearly infinite parameter space to explore, simple parametric design studies cannot possibly search the entire design space within the time frame required to impact the design cycle. For this reason, robust and efficient optimization methods are required to explore and exploit the design space to achieve high performance engine designs. Five case studies which examine the application of various techniques in the engineering environment are presented in this paper

Many-core applications to online track reconstruction in HEP experiments

Interest in parallel architectures applied to real time selections is growing in High Energy Physics (HEP) experiments. In this paper we describe performance measurements of Graphic Processing Units (GPUs) and Intel Many Integrated Core architecture (MIC) when applied to a typical HEP online task: the selection of events based on the trajectories of charged particles. We use as benchmark a scaled-up version of the algorithm used at CDF experiment at Tevatron for online track reconstruction - the SVT algorithm - as a realistic test-case for low-latency trigger systems using new computing architectures for LHC experiment. We examine the complexity/performance trade-off in porting existing serial algorithms to many-core devices. Measurements of both data processing and data transfer latency are shown, considering different I/O strategies to/from the parallel devices.Comment: Proceedings for the 20th International Conference on Computing in High Energy and Nuclear Physics (CHEP); missing acks adde

Dynamics of Convergent Migration and Mean Motion Resonances in Planetary Systems.

Recent observations of solar systems orbiting other stars show that exoplanets display an enormous range of physical properties and that planetary systems display a diverse set of architectures, which motivate further studies in planetary dynamics. Part of the richness of this dynamical problem arises from the intrinsic complexity of $N$-body systems, even in the absence of additional forces. The realm of physical behavior experienced by such systems is enormous, and includes mean motion resonances (MMR), secular interactions, and sensitive dependence on the initial conditions (chaos). Additional complications arise from other forces that are often present: During the early stages of evolution, circumstellar disks provide torques that influence orbital elements, and turbulent fluctuations act on young planets. Over longer time scales, solar systems are affected by tidal forces from both stars and planets, and by general relativistic corrections that lead to orbital precession. This thesis addresses a subset of these dynamical problems, including the capture rates of planets into MMR, collision probabilities for migrating rocky planets interacting with Jovian planets, and the exploration of the ``nodding'' phenomenon (where systems move in and out of MMR). This latter effect can have important implications for interpreting transit timing variations (TTV), a method to detect smaller planets due to their interaction with larger transiting bodies.PhDPhysicsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/107050/1/jaketchm_1.pd

Faculty and Student Online Experiences Amidst the COVID-19 Pandemic: A Descriptive Study (Part 1)

Background: With the declaration of a global pandemic in March 2020, post-secondary institutions closed campuses, learner clinical experiences were suspended, and teaching moved to a fully online format. Prior to data collection, a literature review yielded few results beyond editorials, student and faculty reflections, and blog postings in relation to COVID-19. It is crucial that we learn from the experience of students and faculty to evaluate the novel teaching and learning realized during the pandemic and prioritize a scholarly plan including potential innovative approaches for future educational programming. Objectives: The overall goal for this multi-site research was to capture the perspectives of nursing students, and nursing faculty members on their teaching and learning experiences online during a declared pandemic and provincial state of emergency. Design: Descriptive survey study Setting: Online environment in one province in Eastern Canada Participants: Nursing students and faculty in three Canadian bachelor of science in nursing programs during the spring and summer semester 2020. Method: Participants were invited via email to complete an online survey (via Opinio) related to their experience of learning or teaching in the fully online environment. Results: Quantitative data were analyzed using descriptive (frequencies, means, modes) statistics to describe the experience from the participants’ perspectives and inferential (Chi-square test, t-test) statistics to investigate perceptual differences between the faculty members’ and the students’ perspective related to the effectiveness, engagement, and comfort in the online learning and teaching experience. Qualitative data were analyzed using thematic analysis. The focus of this article is the presentation and discussion of the quantitative data. Conclusions: The resulting knowledge provides an in-depth understanding of the fully online learning and teaching experience during a global pandemic that is invaluable to inform future program planning in relation to online learning and teaching in a practice profession. Résumé Contexte : Avec la déclaration d’une pandémie mondiale en mars 2020, les établissements postsecondaires ont fermé leurs campus, les activités cliniques des apprenantes ont été suspendues et l’enseignement est passé à un format entièrement en ligne. Avant la collecte de données, une revue de la littérature a donné peu de résultats au-delà d’éditoriaux, de réflexions d’étudiantes et de professeures ainsi que d’articles de blogue concernant la COVID-19. Il est essentiel que nous apprenions de l’expérience des étudiantes et des professeures pour évaluer les nouveaux enseignements et apprentissages réalisés pendant la pandémie et prioriser un plan soutenu par la recherche comprenant de potentielles approches avant-gardistes pour les futurs programmes de formation. Objectifs : L’objectif global de cette recherche multisites était de saisir les points de vue des étudiantes et des membres du corps professoral en sciences infirmières sur leurs expériences d’enseignement et d’apprentissage en ligne pendant une pandémie déclarée et un état d’urgence provincial. Devis : Étude descriptive à l’aide d’un sondage. Milieu : Environnement virtuel, dans une province de l’est du Canada. Participantes : Étudiantes en sciences infirmières et membres du corps professoral dans trois programmes canadiens de baccalauréat en sciences infirmières au cours du semestre de printemps et d’été 2020. Méthode : Les participantes ont été invitées par courrier électronique à répondre à un sondage en ligne (par Opinio) au regard de leurs expériences d’apprentissage ou d’enseignement dans un environnement entièrement en ligne. Résultats : Les données quantitatives ont été analysées à l’aide de statistiques descriptives (fréquences, moyennes, modes) pour décrire l’expérience du point de vue des participantes et de statistiques inférentielles (test du chi carré, test de t) pour étudier les différences de perception entre des membres du corps professoral et celle des étudiantes relativement à l’efficacité, à l’engagement et au confort des expériences d’apprentissage et d’enseignement en ligne. Les données qualitatives ont été analysées à l’aide d’une analyse thématique. Les objectifs de cet article sont de présenter et de discuter des résultats quantitatifs. Conclusion : Les connaissances qui en résultent offrent une compréhension approfondie de l’apprentissage et de l’enseignement entièrement en ligne pendant une pandémie mondiale, ce qui est inestimable pour éclairer la planification future des programmes de formation professionnelle comme les sciences infirmières, en ce qui concerne l’apprentissage et l’enseignement en ligne