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Full-Text Articles in Mechanical Engineering
Evaluating Restored Oyster Reefs In Chesapeake Bay: How Habitat Structure Influences Ecological Function, Janet A. Nestlerode
Evaluating Restored Oyster Reefs In Chesapeake Bay: How Habitat Structure Influences Ecological Function, Janet A. Nestlerode
Dissertations, Theses, and Masters Projects
A shortage of shell resources for restoring reefs of the Eastern oyster, Crassostrea virginica, has led to widespread use of substitute materials. The effectiveness of such alternative substrates as habitat for reef-associated fauna other than oysters is largely unresolved. I investigated the habitat value of oyster shell, surf clam (Spisula solidissima) shell, and pelletized coal ash reefs for benthic and nektonic communities. Oyster recruitment, survival, and growth were monitored on reefs of oyster and surf clam shell near the mouth of Chesapeake Bay and York River, USA. Oyster shell supported greater oyster growth and survival and offered the highest degree …
Ultrasonic Guided Wave Tomography Of Pipes: A Development Of New Techniques For The Nondestructive Evaluation Of Cylindrical Geometries And Guided Wave Multi-Mode Analysis, Kevin Raymond Leonard
Ultrasonic Guided Wave Tomography Of Pipes: A Development Of New Techniques For The Nondestructive Evaluation Of Cylindrical Geometries And Guided Wave Multi-Mode Analysis, Kevin Raymond Leonard
Dissertations, Theses, and Masters Projects
This dissertation concentrates on the development of two new tomographic techniques that enable wide-area inspection of pipe-like structures. By envisioning a pipe as a plate wrapped around upon itself, the previous Lamb Wave Tomography (LWT) techniques are adapted to cylindrical structures. Helical Ultrasound Tomography (HUT) uses Lamb-like guided wave modes transmitted and received by two circumferential arrays in a single crosshole geometry. Meridional Ultrasound Tomography (MUT) creates the same crosshole geometry with a linear array of transducers along the axis of the cylinder. However, even though these new scanning geometries are similar to plates, additional complexities arise because they are …