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An Approach to Elemental Task Learning (open access)

An Approach to Elemental Task Learning

In this article we deal with the automated learning of tasks by a robotic system through observation of a human operator. Particularly, we explain what is meant by a learning ability in autonomous robots and in teleoperation systems, where several operators and several machines may work in cooperation to perform tasks. We discuss different approaches to learning in these systems and outline the features of the models they are based upon. This leads us to choose an analytical model suited for tasks analysis. We then present the software architecture for our proposed approach and show the first results obtained on sample tests. 5 refs., 9 figs.
Date: January 1, 1990
Creator: Belmans, P
Object Type: Article
System: The UNT Digital Library
Advances in X-Ray Computed Microtomography at the NSLS (open access)

Advances in X-Ray Computed Microtomography at the NSLS

The X-Ray Computed Microtomography workstation at beamline X27A at the NSLS has been utilized by scientists from a broad range of disciplines from industrial materials processing to environmental science. The most recent applications are presented here as well as a description of the facility that has evolved to accommodate a wide variety of materials and sample sizes. One of the most exciting new developments reported here resulted from a pursuit of faster reconstruction techniques. A Fast Filtered Back Transform (FFBT) reconstruction program has been developed and implemented, that is based on a refinement of the ''gridding'' algorithm first developed for use with radio astronomical data. This program has reduced the reconstruction time to 8.5 sec for a 929 x 929 pixel{sup 2} slice on an R10,000 CPU, more than 8x reduction compared with the Filtered Back-Projection method.
Date: August 7, 1998
Creator: Dowd, B. A.
Object Type: Article
System: The UNT Digital Library
Advances in X-Ray Computed Microtomography at the NSLS (open access)

Advances in X-Ray Computed Microtomography at the NSLS

The X-Ray Computed Microtomography workstation at beamline X27A at the NSLS has been utilized by scientists from a broad range of disciplines from industrial materials processing to environmental science. The most recent applications are presented here as well as a description of the facility that has evolved to accommodate a wide variety of materials and sample sizes. One of the most exciting new developments reported here resulted from a pursuit of faster reconstruction techniques. A Fast Filtered Back Transform (FFBT) reconstruction program has been developed and implemented, that is based on a refinement of the gridding algorithm first developed for use with radio astronomical data. This program has reduced the reconstruction time to 8.5 sec for a 929 x 929 pixel{sup 2} slice on an R10,000 CPU, more than 8x reduction compared with the Filtered Back-Projection method.
Date: August 1, 1998
Creator: Dowd, B. A.; Andrews, A. B.; Marr, R. B.; Siddons, D. P.; Jones, K. W. & Peskin, A. M.
Object Type: Article
System: The UNT Digital Library
Automated Corrosion System in a Moist Environment (open access)

Automated Corrosion System in a Moist Environment

In an effort to assist researchers investigating the moisture-generated corrosion of metals and ceramics, a unique exposure system was developed. The initial goal of this system was to monitor corrosion ranging from a few monolayers at the outset of the corrosion process to high mass gains in more extensively corroded material. The new system uses a small robot arm for sample manipulation; gravimetric and Fourier transform infrared (FTIR) spectroscopy for corrosion-product determination; and a gas blending system to control the moisture content of the glove box in which the system is housed. The system's computer control can be configured to coordinate the examination of as many as 20 samples by periodic weighing and FTIR scanning. The computer also performs such functions as data logging of the temperature and pressure of the system and of the flow rate and moisture content of the purge gas. One main benefit of the computer-controlled robotic system is its ability to monitor samples 2 4 hours a day with precision control; this reduces problems stemming from human error or inconsistency of human technique.
Date: March 19, 1999
Creator: Hallman, R. L., Jr. & Calhoun, C.L.
Object Type: Article
System: The UNT Digital Library
Air Quality Analysis and Related Risk Assessment for the Bonneville Power Administration's Resource Program Environmental Impact Statement (open access)

Air Quality Analysis and Related Risk Assessment for the Bonneville Power Administration's Resource Program Environmental Impact Statement

The Bonneville Power Administration (BPA) is considering 12 different alternatives for acquiring energy resources over the next 20 years. Each of the alternatives utilizes a full range of energy resources (e.g., coal, cogeneration, conservation, and nuclear); however, individual alternatives place greater emphases on different types of power-producing resources and employ different timetables for implementing these resources. The environmental impacts that would result from the implementation of each alternative and the economic valuations of these impacts, will be an important consideration in the alternative selection process. In this report we discuss the methods used to estimate environmental impacts from the resource alternatives. We focus on pollutant emissions rates, ground-level air concentrations of basic criteria pollutants, the acidity of rain, particulate deposition, ozone concentrations, visibility attenuation, global warming, human health effects, agricultural and forest impacts, and wildlife impacts. For this study, pollutant emission rates are computed by processing BPA data on power production and associated pollutant emissions. The assessment of human health effects from ozone indicated little variation between the resource alternatives. Impacts on plants, crops, and wildlife populations from power plant emissions are projected to be minimal for all resource alternatives.
Date: April 1, 1992
Creator: Glantz, C. S.; Burk, K. W.; Driver, C. J.; Liljegren, J. C.; Neitzel, D. A.; Schwartz, M. N. et al.
Object Type: Report
System: The UNT Digital Library
Adoption, Implementation and Enforcement of Commercial Building Energy Codes in New Mexico and Arizona (open access)

Adoption, Implementation and Enforcement of Commercial Building Energy Codes in New Mexico and Arizona

The US Department of Energy (DOE) is considering ways to encourage states to adopt energy efficiency standards for residential and commercial buildings in the private sector. Such standards are now mandatory for federal buildings, and for private buildings in 34 states; in the remaining 16 states, the standards serve as guidelines for voluntary compliance. In this study for DOE, Pacific Northwest Laboratory (PNL) assessed the process by which energy codes for commercial buildings were adopted and implemented in Arizona and New Mexico. Information was gathered primarily through a series of interviews with state officials, city building officials, architects and engineers, builders, and staff from utilities in the two states. Until other state processes are studied, the extent of the similarities and dissimilarities to the situation in New Mexico and Arizona are unknown. A more extensive study may show that at least some elements of the two state's experience have been paralleled in other parts of the country. General strategies to encourage the adoption of energy codes, assist implementation, and support enforcement were developed based on the research from Arizona and New Mexico and are presented in this report. 6 refs., 4 figs.
Date: July 1, 1991
Creator: Callaway, J. W.; Thurman, A G & Shankle, D L
Object Type: Report
System: The UNT Digital Library
Artificial Intelligence Technology Assessment for the Us Army Depot System Command (open access)

Artificial Intelligence Technology Assessment for the Us Army Depot System Command

This assessment of artificial intelligence (AI) has been prepared for the US Army's Depot System Command (DESCOM) by Pacific Northwest Laboratory. The report describes several of the more promising AI technologies, focusing primarily on knowledge-based systems because they have been more successful in commercial applications than any other AI technique. The report also identifies potential Depot applications in the areas of procedural support, scheduling and planning, automated inspection, training, diagnostics, and robotic systems. One of the principal objectives of the report is to help decision makers within DESCOM to evaluate AI as a possible tool for solving individual depot problems. The report identifies a number of factors that should be considered in such evaluations. 22 refs.
Date: July 1, 1991
Creator: Pennock, K. A.
Object Type: Report
System: The UNT Digital Library
Air Pathway Report: Phase I of the Hanford Environmental Dose Reconstruction Project (open access)

Air Pathway Report: Phase I of the Hanford Environmental Dose Reconstruction Project

Phase 1 of the air-pathway portion of the Hanford Environmental Dose Reconstruction (HEDR) Project sought to determine whether dose estimates could be calculated for populations in the 10 counties nearest the Hanford Site from atmospheric releases of iodine-131 from the site from 1944--1947. Phase 1 demonstrated the following: HEDR-calculated source-term estimates of iodine-131 releases to the atmosphere were within 20% of previously published estimates; calculated vegetation concentrations of iodine-131 agree well with previously published measurements; the highest of the Phase 1 preliminary dose estimates to the thyroid are consistent with independent, previously published estimates of doses to maximally exposed individuals; and, relatively crude, previously published measurements of thyroid burdens for Hanford workers are in the range of average burdens that the HEDR model estimated for similar reference individuals for the period 1944--1947. Preliminary median dose estimates summed over the year 1945--1947 for the primary pathway, air-pasture-cow-milk-thyroid, ranged from low median values of 0.006 rad for upwind adults who obtained milk from backyard cows not on pasture to high median values of 68.0 rad for downwind infants who drank milk from pasture-fed cows. Extremes of the estimated range are a low of essentially zero to upwind adults and a high of …
Date: July 1, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
An Approach for Assessing Alwr Passive Safety System Reliability (open access)

An Approach for Assessing Alwr Passive Safety System Reliability

Many advanced light water reactor designs incorporate passive rather than active safety features for front-line accident response. A method for evaluating the reliability of these passive systems in the context of probabilistic risk assessment has been developed at Sandia National Laboratories. This method addresses both the component (e.g. valve) failure aspect of passive system failure, and uncertainties in system success criteria arising from uncertainties in the system's underlying physical processes. These processes provide the system's driving force; examples are natural circulation and gravity-induced injection. This paper describes the method, and provides some preliminary results of application of the approach to the Westinghouse AP600 design.
Date: January 1, 1991
Creator: Hake, T. M.
Object Type: Article
System: The UNT Digital Library
Archaeological survey of the 200 East and 200 West Areas, Hanford Site, Washington (open access)

Archaeological survey of the 200 East and 200 West Areas, Hanford Site, Washington

Responding to a heavy demand for cultural resource reviews of excavation sites, the Westinghouse Hanford Company contracted with Pacific Northwest Laboratory to conduct a comprehensive archaeological resource review for the 200 Areas of the Hanford Site, Washington. This was accomplished through literature and records review and an intensive pedestrian survey of all undisturbed portions of the 200 East Area and a stratified random sample of the 200 West Area. The survey, followed the Secretary of the Interior's guidelines for the identification of historic properties. The result of the survey is a model of cultural resource distributions that has been used to create cultural resource zones with differing degrees of sensitivity. 11 refs., 7 figs., 1 tab.
Date: March 1, 1990
Creator: Chatters, J. C. & Cadoret, N. A.
Object Type: Report
System: The UNT Digital Library