7,530 research outputs found
Preliminary results of measurements of sq currents and the equatorial electrojet near peru
Measurement of electric current, magnetic field, and electron density in ionosphere using Nike-Apache sounding rocket
Evaluation of the Spherical Flange Concept for a Rocket Engine
Due to the inherent tolerance variability of hardware, flange misalignments occur during installation of mating components for a liquid propellant rocket engine. Flange misalignments include axial, lateral, and angular offsets. If these misalignments are high, they can impart significant loads into the two mating components. These significant loads can then be a driver in the design of the propellant ducts. Such was the case for the Rocketdyne RS-83 engine design for the Space Launch Initiative Program. To address this flange misalignment issue, Marshall Space Flight Center joined with Rocketdyne to develop and test a spherical flange system that allows for misalignment, yet reduces loads imparted, and at the same time provides sufficient sealing against leakage. The flange design was tested to evaluate and compare performance parameters such as misalignment and leakage. The environmental conditions ranged from -100 to 400 degrees Fahrenheit (F) with 1000 to 4000 pounds per square inch gage (psig) pressure. The desirable design features will be extracted and synthesized into a new flange design concept. This paper will address the spherical flange design and the test results
Shear flexibility for structures
This device comprises a flexible sheet member having cross convolutions oriented 45.degree. to the shear vector with spherical reliefs at the convolution junctions. The spherical reliefs are essential to the shear flexibility by interrupting the principal stress lines that act along the ridges of the convolutions. The spherical reliefs provide convolutions in both directions in the plane of the cross-convolution ridges
Specific Pathogen Free Swine
Control of diseases in domestic animals is attempted for two main reasons: 1. To reduce reservoirs of disease transmissible to man, and 2. to produce livestock more economically
Optimization of laser-plasma injector via beam loading effects using ionization-induced injection
Simulations of ionization induced injection in a laser driven plasma
wakefield show that high-quality electron injectors in the 50-200 MeV range can
be achieved in a gas cell with a tailored density profile. Using the PIC code
Warp with parameters close to existing experimental conditions, we show that
the concentration of in a hydrogen plasma with a tailored
density profile is an efficient parameter to tune electron beam properties
through the control of the interplay between beam loading effects and varying
accelerating field in the density profile. For a given laser plasma
configuration, with moderate normalized laser amplitude, and maximum
electron plasma density, , the
optimum concentration results in a robust configuration to generate electrons
at 150~MeV with a rms energy spread of 4\% and a spectral charge density of
1.8~pC/MeV.Comment: 13 pages, 10 figure
A hatful of rain, by Michael V. Gazzo. Thesis production book prepared by Jacques L. Maynard
Thesis (M.F.A.)--Boston Universit
A Transcendental Phenomenological Study of Quality-of-Life Training in Self-Regulation Skills of Young Adults with Asperger\u27s Syndrome
The purpose of this transcendental phenomenological study was to understand lived experiences in young adults with Asperger’s syndrome (AS) as they transitioned out of high school after completion of quality-of-life training. The theories guiding this study were Ivan Pavlov’s classical conditioning and Adam Morton’s theory of mind in predictive behaviors. Pavlov’s theory relates to understanding whether individuals could be classically conditioned to reinforce a natural reflex or some involuntary behavior that would occur as a response to classical conditioning. Morton’s theory helped focus this phenomenological study by describing the training in predictive behaviors by conceptual structure. Participants were selected from local high schools, colleges, and universities using purposeful sampling data collected through a triangulation of three methods: surveys, interviews, and focus groups. The analysis used was Moustakas transcendental phenomenological approach. Data collection results generated themes of challenges in social communication, academics, employment, and self-sufficiency. The two major themes prevalent were challenges in both social communications and self-sufficiency since completing QoL training in high school. There are empirical, practical, and theoretical implications of data analysis and recommendations for future research. Empirical research was examined to determine a curriculum-based instruction vocational training program that would help equip young adults with AS to transition to self-regulation toward self-sufficiency. Young adults with AS would function in postsecondary education with the knowledge to identify beneficial accommodations and supports learned in quality-of-life training
Some Things Grew No Less With Time: Tracing ATU 510B from the Thirteenth to the Twentieth Century
This thesis provides a comparative analysis of seven different variants of the fairy tale commonly known as “Donkeyskin,” classified in the Aarne-Thompson-Uther folktale motif index as ATU 510B. By comparing so many different iterations of one fairy tale, it is easier to recognize the inherent attitudes concerning women and their place in society contained in this tale. Additionally, reading multiple variants from different centuries lends a perspective on the way that these attitudes changed over the centuries. Each of the thirteenth century texts considered end with their heroines trapped in loveless marriages, much like the seventeenth-century fairy tale, “Donkeyskin,” their direct literary descendant. The nineteenth century texts then present death or marriage as the alternatives for women, while the twentieth century brings the first instance of a heroine choosing for herself. This comparison allows the reader to learn not only what was considered a “happy ending” at the time, but also to gain a better understanding of the means by which a woman could gain agency
Changing Relationship Between Official and Self-Reported Measures of Delinquency: An Exploratory-Predictive Study, The
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