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Using Single-Camera 3-D Imaging to Guide Material Handling Robots in a Nuclear Waste Package Closure System (open access)

Using Single-Camera 3-D Imaging to Guide Material Handling Robots in a Nuclear Waste Package Closure System

Nuclear reactors for generating energy and conducting research have been in operation for more than 50 years, and spent nuclear fuel and associated high-level waste have accumulated in temporary storage. Preparing this spent fuel and nuclear waste for safe and permanent storage in a geological repository involves developing a robotic packaging system—a system that can accommodate waste packages of various sizes and high levels of nuclear radiation. During repository operation, commercial and government-owned spent nuclear fuel and high-level waste will be loaded into casks and shipped to the repository, where these materials will be transferred from the casks into a waste package, sealed, and placed into an underground facility. The waste packages range from 12 to 20 feet in height and four and a half to seven feet in diameter. Closure operations include sealing the waste package and all its associated functions, such as welding lids onto the container, filling the inner container with an inert gas, performing nondestructive examinations on welds, and conducting stress mitigation. The Idaho National Laboratory is designing and constructing a prototype Waste Package Closure System (WPCS). Control of the automated material handling is an important part of the overall design. Waste package lids, welding equipment, …
Date: September 1, 2005
Creator: Shurtliff, Rodney M.
System: The UNT Digital Library
Using Unmanned Aerial Vehicles to Assess Vegetative Cover in Sagebrush Steppe Ecosytstems (open access)

Using Unmanned Aerial Vehicles to Assess Vegetative Cover in Sagebrush Steppe Ecosytstems

The Idaho National Laboratory (INL), in conjunction with the University of Idaho, is evaluating novel approaches for using unmanned aerial vehicles (UAVs) as a quicker and safer method for monitoring biotic resources. Evaluating vegetative cover is an important factor in understanding the sustainability of many ecosystems. In assessing vegetative cover, methods that improve accuracy and cost efficiency could revolutionize how biotic resources are monitored on western federal lands. Sagebrush steppe ecosystems provide important habitat for a variety of species, some of which are important indicator species (e.g., sage grouse). Improved methods are needed to support monitoring these habitats because there are not enough resource specialists or funds available for comprehensive ground evaluation of these ecosystems. In this project, two types of UAV platforms (fixed wing and helicopter) were used to collect still-frame imagery to assess cover in sagebrush steppe ecosystems. This paper discusses the process for collecting and analyzing imagery from the UAVs to (1) estimate total percent cover, (2) estimate percent cover for six different types of vegetation, and (3) locate sage grouse based on representative decoys. The field plots were located on the INL site west of Idaho Falls, Idaho, in areas with varying amounts and types of …
Date: September 1, 2005
Creator: Breckenridge, Robert P.
System: The UNT Digital Library
THE VALIDITY OF HUMAN AND COMPUTERIZED WRITING ASSESSMENT (open access)

THE VALIDITY OF HUMAN AND COMPUTERIZED WRITING ASSESSMENT

This paper summarizes an experiment designed to assess the validity of essay grading between holistic and analytic human graders and a computerized grader based on latent semantic analysis. The validity of the grade was gauged by the extent to which the student’s knowledge of the topic correlated with the grader’s expert knowledge. To assess knowledge, Pathfinder networks were generated by the student essay writers, the holistic and analytic graders, and the computerized grader. It was found that the computer generated grades more closely matched the definition of valid grading than did human generated grades.
Date: September 1, 2005
Creator: Boring, Ronald L.
System: The UNT Digital Library
Voltage spikes in Nb3Sn and NbTi strands (open access)

Voltage spikes in Nb3Sn and NbTi strands

As part of the High Field Magnet program at Fermilab several NbTi and Nb{sub 3}Sn strands were tested with particular emphasis on the study of voltage spikes and their relationship to superconductor instabilities. The voltage spikes were detected under various experimental conditions using voltage-current (V-I) and voltage-field (V-H) methods. Two types of spikes, designated ''magnetization'' and ''transport current'' spikes, have been identified. Their origin is most likely related to magnetization flux jump and transport current redistribution, respectively. Many of the signals observed appear to be a combination of these two types of spikes; the combination of these two instability mechanisms should play a dominant role in determining the minimum quench current.
Date: September 1, 2005
Creator: Bordini, B.; Ambrosio, G.; Barzi, E.; Carcagno, R.; Feher, S.; Kashikhin, V. V. et al.
System: The UNT Digital Library
Whole-genome shotgun optical mapping of Rhodospirillum rubrum (open access)

Whole-genome shotgun optical mapping of Rhodospirillum rubrum

Rhodospirillum rubrum is a phototrophic purple nonsulfur bacterium known for its unique and well-studied nitrogen fixation and carbon monoxide oxidation systems and as a source of hydrogen and biodegradable plastic production. To better understand this organism and to facilitate assembly of its sequence, three whole-genome restriction endonuclease maps (XbaI, NheI, and HindIII) of R. rubrum strain ATCC 11170 were created by optical mapping. Optical mapping is a system for creating whole-genome ordered restriction endonuclease maps from randomly sheared genomic DNA molecules extracted from cells. During the sequence finishing process, all three optical maps confirmed a putative error in sequence assembly, while the HindIII map acted as a scaffold for high-resolution alignment with sequence contigs spanning the whole genome. In addition to highlighting optical mapping's role in the assembly and confirmation of genome sequence, this work underscores the unique niche in resolution occupied by the optical mapping system. With a resolution ranging from 6.5 kb (previously published) to 45 kb (reported here), optical mapping advances a "molecular cytogenetics" approach to solving problems in genomic analysis.
Date: September 1, 2005
Creator: Reslewic, S.; Zhou, S.; Place, M.; Zhang, Y.; Briska, A.; Goldstein, S. et al.
System: The UNT Digital Library