Excavations at the Cooper’s Ferry site (10IH73) revealed a long record of repeated human occupation extending from the late Pleistocene into the early Holocene (~16,000-10,000 cal BP) and have yielded unique insights into the Western Stemmed Tradition (WST), which includes. Several studies have focused on WST pit features encountered at...
Among the candidates for the next generation of nuclear power plant is the high temperature gas reactor (HTGR). Since the HTGR does not have the same operational history as water cooled reactors do in the United States, investigation into the response of different accident phenomena is still an active area...
Nanoscale Instrumented Indentation Testing (IIT) is a material characterization technique that is used to determine mechanical properties. The size effects present at this scale make it difficult to expand findings to a bulk scale. Modeling can be used to bridge this gap and better understand nanoscale IIT and the size...
Studies of Hawaiian volcanoes contribute valuable insights about Earth processes and mantle evolution, and are fundamental for understanding the construction of the largest volcanoes on terrestrial planets. The pre-shield stage exists in every Hawaiian volcano, but is usually blanketed by high volume tholeiitic lava flows during the main shield stage....
Textiles (including basketry, cordage, woven, knotted, or plaited products) make up a considerable portion of the perishable archaeological record in dry caves of the northern Great Basin region, much of which is created from plants and plant fibers. The archaeological study of precontact textiles greatly informs our understanding of how...
There is a growing need for an expanded Probabilistic Risk Assessment (PRA) framework that is able to accommodate new uncertainties that are present in Generation 3+ reactor designs. Dynamic PRA (DPRA) can allow for a more realistic risk assessment by taking advantage of established nuclear simulation codes to drive Dynamic...
The neutron flux-energy spectral characterization of a Thermo Fisher MP320 deuterium-tritium neutron generator was performed for two shielding configurations, one with substantial moderator between the source and the sample and one without such moderator. The STAYSL PNNL spectral adjustment code was utilized in conjunction with MCNP modelled reference spectra and...
Neutron radiography has been used to study cementitious materials. This thesis studies the impact of heavy water on both the rate of hydration and neutron radiography. The neutron attenuation coefficients of light and heavy water were measured. Cement pastes were made with both heavy and light water. The attenuation coefficients...
Advances in technology such as 3D digital scanning and spatial analysis software have provided archaeologists with novel data. Specifically, these methods increase the researcher's ability to measure artifact morphology and past networks of cultural transmission, to potentially track the movement of past peoples and ideas through space and time. This...
Archaeological investigations at the Cooper's Ferry site in Western Idaho have recovered cultural remains dating to 16,000 years ago, suggesting the oldest human occupation recorded in North America. However, many archaeologists have argued the initial peopling of North America occurred no earlier than the opening of an ice-free corridor between...