Engineering Commons^™

An Investigation Into The Prediction Of Double-Skin Penetration Within Chromite Molds And Cores In Heavy Section Steel Casting Using Process Simulation Software, Nathaniel Bryant

Dissertations and Theses @ UNI

This investigation was conducted in response to a commercial steel foundry approaching the University of Northern Iowa for assistance with a recurring defect they experienced on a production casting. The defect was described as a mass of metal that penetrated and consumed the interstices of their chromite molds and cores, and it was determined to consist of fayalite. After an extensive literature review, it was concluded that the foundry experienced the double-skin defect, a niche quality issue that most commonly occurs in heavy-section steel casting with chromite molding materials

After it was determined that the double-skin defect was occurring, a …

Assessing Endothelial Dysfunction Estimating The Differences Between 3 Minute And 5 Minute Reactive Hyperemia, Tamiko K. Saldin

Master's Theses

The purpose of this study was to define a lower standard cuff occlusion time to induce reactive hyperemia in assessing endothelial dysfunction. In this study, strong evidence was found by a novel technique that used oscillometric methods, which supported that 3 minute reactive hyperemia was sufficient to elicit a significant difference in arterial compliance from baseline. Twenty healthy Cal Poly students were assessed, (n=12 female, n=8 male) aged 22 years old with a standard deviation of 2.04 years. Arterial compliance was estimated by measuring the peak-to-peak oscillations for baseline, 3 minute reactive hyperemia, and 5 minute reactive hyperemia tests, with …