EXPERIMENTAL STUDIES OF FATIGUE PERFORMANCE OF INCONEL 718 AND FIBERGLASS REINFORCED VINYLESTER

Fatigue performance of structural materials depend on their microstructure and manufacturing processes. In this thesis, two different materials are investigated: additively manufactured Inconel 718 and a fiberglass reinforced vinylester composite. The microstructural features of a direct metal laser sintered Inconel 718 are compared to a traditionally manufactured wrought Inconel 718. The effects of 3D printing direction and heat treatment are studied. Low cycle fatigue specimens manufactured by Turbocam International are tested at strain amplitudes from 0.6% to 1.4% engineering strain. These data are correlated to the microstructural features seen in the electron backscatter diffraction. High cycle fatigue specimens are tested at stress amplitudes ranging from 200 MPa to 1200 MPa. Images of the fracture surfaces are utilized to find trends in the ductile and brittle fracture areas on the surface to understand the material performance in fatigue. Strain-life and stress-life curves are generated for the low cycle and high cycle fatigue data, respectively. The low cycle fatigue performance of fiberglass reinforced vinylester is also investigated. Specimens manufactured by HALO Maritime Defense Systems are subjected to tension-tension fatigue loading with maximum stresses ranging from 250 MPa to 350 MPa. A stress-life curve is generated and the results are compared to data from literature. It is observed that these composite materials have high uncertainty in fatigue performance so it is recommended to use a lower bound S-N curve for design purposes

Alien Registration- Gribbin, Catherine (Portland, Cumberland County)

https://digitalmaine.com/alien_docs/31391/thumbnail.jp

A robust method for measuring the Hubble parameter

We obtain a robust, non-parametric, estimate of the Hubble constant from galaxy linear diameters calibrated using HST Cepheid distances. Our method is independent of the parametric form of the diameter function and the spatial distribution of galaxies and is insensitive to Malmquist bias. We include information on the galaxy rotation velocities; unlike Tully-Fisher, however, we retain a fully non-parametric treatment. We find $H_0=66\pm6$ km/s/Mpc, somewhat larger than previous results using galaxy diameters.Comment: 4 pages, 1 figure, Cosmic Flows Workshop, Victoria B.C. Canada, July 1999, ed. S. Courteau, M. Strauss & J. Willick, ASP conf. serie

The occupational work ethic of student workers : a generational approach

This study was conducted to investigate the occupational work ethic of student workers at The University of Tennessee from a generational approach. The purpose of this study was to establish baseline data establishing the occupational work ethic of student workers and to identify demographic trends within the sample. Once identified, this information provided The University of Tennessee with insights into the work ethic of student workers. This comprehensive understanding of the work ethic may lead to more effective student worker services, such as tailored training initiatives . TI1e subjects in this study were students who were enrolled in courses and employed part-time by The University of Tennessee during spring semester 2002. The Occupational Work Ethic Inventory (OWEI), designed by Petty, was used to determine the occupational work ethic of the subjects. The OWEI examines work ethic in three subscales: (a) interpersonal skills, (b) initiative, and (c) being dependable. Means, standard deviations, correlations and frequency counts were the descriptive statistics methods used to analyze responses to the numeric research questions. A multiple analysis of variance (MANOVA) was used to analyze the continuous demographic information as determined by the independent variables. Cronbach\u27s Alpha was calculated to investigate the three subscale categories. The results indicated a significant relationship between the occupational work ethic subscales and gender. Females tended to have significantly higher score than did males for two of the three subscales. No significant relationships were found between the occupational work ethic and various demographic variables

The Glass Eeling: Maine’s Glass Eel and Elver Regulations and Their Effects on Maine’s Native American Tribes

Until recently, elvers and glass eels were not commercially popular aquatic creatures. However, a tsunami and European ban depleted Asian supplies, which rapidly increased the demand for American elvers and glass eels. The increased demand for elvers has driven their price from hundreds of dollars to thousands of dollars per pound. This increased profit margin has caused many additional individuals to begin fishing for elvers in states in which elvers are numerous and widespread, including Maine. The initial increase in elver fishing began in 2012. By 2013, the impact of the increased fishing began to produce adverse effects on the Maine elver fishery. Because of these effects, the state legislature passed emergency, sweeping legislation in early 2013, days before the elver season was scheduled to begin. Although this legislation, and the regulations established thereunder, are applicable to all individuals harvesting elvers within Maine, the laws and regulations have had several unfavorable effects on Maine Indian tribal members. These effects are based on confusion regarding the applicability of laws that establish certain rights of the Maine Indian tribes, bands, or nations, and their relationship with the sweeping elver laws established in 2013. This Comment discusses the relationship between the State of Maine and Maine’s Native American tribes, and the intersection between the conversation of Native American heritage and the State’s interest in environmental protection. Part II discusses the lifecycle of the American eel and what distinguishes glass eels and elvers from the eel’s other life stages. Part III considers the recent increases in the popularity and value of elvers and glass eels. Part IV examines the peculiar rights of Maine’s Native American tribes and nations, and the process by which those rights were created. Part V reviews the recent changes in elver regulations that occurred in Maine and along the Atlantic Coast. Part VI discusses the ways in which Maine’s tribes have been impacted by the new regulations. Finally, Part VII determines whether the tribes and nations are excluded from the new regulations by determining whether they retained sovereignty over particular natural resources