545 research outputs found
Ground Support for the Space-Based Range Flight Demonstration 2
The primary objective of the NASA Space-Based Range Demonstration and Certification program was to develop and demonstrate space-based range capabilities. The Flight Demonstration 2 flights at NASA Dryden Flight Research Center were conducted to support Range Safety (commanding and position reporting) and high-rate (5 Mbps) Range User (video and data) requirements. Required ground support infrastructure included a flight termination system computer, the ground-data distribution network to send range safety commands and receive range safety and range user telemetry data and video, and the ground processing systems at the Dryden Mission Control Center to process range safety and range user telemetry data and video
Water Tree Analysis and On-Line Detection Algorithm Using Time Domain Relectometry
With the increasing amount of overhead lines being converted to underground cables in the distribution system, the need to be able to determine the health of these underground cables becomes imperative. Since the health of underground cables cannot be determined by visual means like overhead lines, an on-line measurement method is needed to determine the health of these cables. By sending a high frequency voltage pulse down the cable and measuring the return pulse, a method called time domain reflectomentry (TDR), an on-line measurement method becomes feasible. One of the main causes of cable failure is known as water-trees, and they are formed through dielectric breakdown of the cables insulation. They are formed from electrical stress at the interface of the cables’ insulation and conductors. To determine an on-line measurement method to detect water trees, an accurate model of water-trees in underground cables is developed. Two different cable types are modeled with water-trees, concentric neutral and tape shield cables. These models are developed in COMSOL Multiphysics®. With this developed water-tree model, it is then integrated into a distribution feeder located along the coast of South Carolina, with parameters provided by Santee Cooper®. To perform TDR and monitor the health of all the three-phase cables in the distribution feeder an optimal pulse generators placement algorithm was used to determine the location of pulse generators to monitor all cables. Finally, an algorithm for monitoring every cable was created and the method tested in PSCAD®. Based on these results an on-line measurement water-tree detection method is presented
Religious and Ceremonial Microartifacts from the Winterville Archaeological Site (22WS500)
The Winterville Archaeological Site (22WS500), located near Greenville, Mississippi, served as a ceremonial center during the Mississippian Period (approximately 1000-1500 AD). Originally consisting of twenty-three or more mounds, Winterville was a significant social and religious gathering place and was home to the elite classes of the society. This study analyses microartifacts from two locations on the site, leading to comparisons and conclusions of the types of religious activities occurring at each. Mound C was home to an elite group while Mound B likely served as a temple or religiously significant mound. The findings indicate that elites and elite mounds played a special religious role in Winterville society and were more accessible to the masses than Mound B may have been. The study explores the role that elites may have taken in Mississippian religious practices by drawing comparisons with ethnographic research from other Native American groups
Releasing Authority Chairs: A Comparative Snapshot Across Three Decades
This report provides a comparative analysis of releasing authority chairs' views of the issues and challenges confronting them at two points in time: 1988 and 2015. Drawing from two surveys, one conducted during the tenure of an ACA Parole Task Force that functioned from 1986-1988, and the other a survey published in 2016 by the Robina Institute called The Continuing Leverage of Releasing Authorities: Findings from a National Survey, this new publication highlights both change and constancy relative to a wide range of comparative markers including, but not limited to, structured decision tools, prison crowding and risk aversion, and the myriad factors considered in granting or denying parole
College of Business and Public Administration
This departmental history was written on the occasion of the UND Quasquicentennial in 2008.https://commons.und.edu/departmental-histories/1066/thumbnail.jp
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