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Building a bridge with the customer to facilitate collecting and validating information in modeling sessions (open access)

Building a bridge with the customer to facilitate collecting and validating information in modeling sessions

To build a bridge with customers, we balance the linear modeling process with the dynamics of the individuals we serve, who may feel unfamiliar, even confused, with that process. While it is recognized that human factors engineers improve the physical aspect of the workplace, they also work to integrate customers` cognitive styles, feelings, and concerns into the workplace tools. We take customers` feelings into consideration and integrate their expressed needs and concerns into the modeling sessions. After establishing an agreeable, professional relationship, we use a simple, portable CASE tool to reveal the effectiveness of NIAM. This tool, Modeler`s Assistant, is friendly enough to use directly with people who know nothing of NIAM, yet it captures all the information necessary to create complete models. The Modeler`s Assistant succeeds because it organizes the detailed information in an enhanced text format for customer validation. Customer cooperation results from our modeling sessions as they grow comfortable and become enthused about providing information.
Date: July 21, 1994
Creator: Eaton, S. M.
System: The UNT Digital Library
CANDID: Comparison algorithm for navigating digital image databases (open access)

CANDID: Comparison algorithm for navigating digital image databases

In this paper, we propose a method for calculating the similarity between two digital images. A global signature describing the texture, shape, or color content is first computed for every image stored in a database, and a normalized distance between probability density functions of feature vectors is used to match signatures. This method can be used to retrieve images from a database that are similar to an example target image. This algorithm is applied to the problem of search and retrieval for database containing pulmonary CT imagery, and experimental results are provided.
Date: February 21, 1994
Creator: Kelly, P. M. & Cannon, T. M.
System: The UNT Digital Library
Potential worker risk as a function of CAM airflow rate (open access)

Potential worker risk as a function of CAM airflow rate

The goal of the continuous air monitor (CAM) system at the Los Alamos National Laboratory`s Plutonium Facility (PF-4) is to have a flow rate of 1 cubic feet per minute (cfm) drawn through the CAMs. However, design limitations in the house vacuum result in many CAMs having less than 1 cfm being drawn through them. Reduced flow rates through CAMs present a compromise in worker protection. Laboratory Health and Safety personnel and DOE officials established a flow rate of 0.5 cfm or less as operationally unacceptable. This report quantitatively estimated the difference in risk to workers from a reduced flow rate of 0.5 cfm relative to the risk inherent with a flow rate of 1 cfm. I calculated risk in terms of Committed Effective Dose Equivalent (CEDE) and used units of rem. Estimates for the increase in risk for 0.5 cfm compared to 1 cfm ranged from 0.32 rem to 3.3 rem. The difference in the minimum alarm concentration between 0.5 cfm and I cfm was also compared and was estimated to range from 0.4 rem to 4 rem.
Date: March 21, 1994
Creator: Whicker, J. J.
System: The UNT Digital Library
Using the technical planning and evaluation course to demonstrate an integrated approach to technological risk analysis and protective action decision making (open access)

Using the technical planning and evaluation course to demonstrate an integrated approach to technological risk analysis and protective action decision making

None
Date: April 21, 1994
Creator: Coomer, C. J.; Copenhaver, E. D.; Clevenger, W. F. & Thompson, P. G.
System: The UNT Digital Library
A multisite interaction expansion of the total energy in metals (open access)

A multisite interaction expansion of the total energy in metals

The local-density approximation provides a proper setting for the decomposition of total energy into many-body (many-atom) contributions. Multiple scattering theory in turn provides a convenient framework for carrying out this process. We illustrate this concept with calculations on a linear chain of atoms in bulk copper.
Date: July 21, 1994
Creator: Sowa, E. C. & Gonis, A.
System: The UNT Digital Library
Inner-shell photo-ionized X-ray laser schemes for low-Z elements (open access)

Inner-shell photo-ionized X-ray laser schemes for low-Z elements

Gain calculations for inner-shell photo-ionized lasing in C at 45 {angstrom} are performed. An incident x-ray source represented by a 150 eV blackbody with a rise time of 50 fsec gives a gain of order 10 cm{sup {minus}1}. The x-ray source and thus the driving optical laser requirements are significantly reduced as compared to what is needed for Ne at 15 {angstrom}. The authors expect that existing ultra-short pulse lasers can produce the required x-ray source and thus produce a table-top x-ray laser at 45 {angstrom}.
Date: October 21, 1994
Creator: Moon, S. J.; Eder, D. C. & Strobel, G. L.
System: The UNT Digital Library
Preparation of random phase plates for laser beam smoothing (open access)

Preparation of random phase plates for laser beam smoothing

Phase plates are required for removing aberrations from laser beams caused by inhomogeneities in the optical components of the laser. The first type of plate that we prepared consisted of a bi-level optical component that caused spatial smoothing of the beam by breaking it up into a fine scale spatial structure. This was made by etching a pattern directly into the substrate using HF/NH{sub 4}F. Components up to 80 cm in diameter were prepared but these are only 85% efficient because of beam losses in secondary maxima. Multilevel designs are more efficient and we have prepared 5 inch diameter samples with 16 levels. These require four separate etch steps but have efficiencies greater than 90%.
Date: November 21, 1994
Creator: Thomas, I. M.; Dixit, S. N. & Rushford, M. C.
System: The UNT Digital Library
Facility agreements under the chemical weapons convention inspections (open access)

Facility agreements under the chemical weapons convention inspections

The Chemical Weapons Convention (CWC) poses problems of constitutionality, of loss of confidential business information, and even of plant safety. An entirely new and complex worldwide regulatory regime, it nevertheless takes account of the need for certainty in the conduct of industrial production. In particular, the CWC provides for site-specific inspection protocols, called {open_quotes}facility agreements{close_quotes}. Facility agreements are not defined in the CWC, but are to be developed as part of the preparations preceding formal entry into force. In effect, they can be thought of as {open_quotes}inspection contracts{close_quotes} governing facilities subject to systematic and routine inspections. Facility agreements are not part of challenge inspections or for cases of alleged use of chemical weapons. The most important fact about facility agreements is that they are not negotiated between the facility owner or operator and the OPCW. Rather, they are negotiated between the State Party and the OPCW. Where United States facilities, such as chemical weapons production facilities, are owned by the government or are under government contract this is not a problem because the government can negotiate on its own behalf. However, where privately owned facilities in the United States enter into facility agreements, the input of those private entities into …
Date: October 21, 1994
Creator: Tanzman, E. A.
System: The UNT Digital Library
Borehole induction logging for the Dynamic Underground Stripping Project LLNL gasoline spill site (open access)

Borehole induction logging for the Dynamic Underground Stripping Project LLNL gasoline spill site

Borehole induction logs were acquired for the purpose of characterizing subsurface physical properties and monitoring steam clean up activities at the Lawrence Livermore National Laboratory. This work was part of the Dynamic Underground Stripping Project`s demonstrated clean up of a gasoline spin. The site is composed of unconsolidated days, sands and gravels which contain gasoline both above and below the water table. Induction logs were used to characterize lithology, to provide ``ground truth`` resistivity values for electrical resistance tomography (ERT), and to monitor the movement of an underground steam plume used to heat the soil and drive volatile organic compounds (VOCs) to the extraction wells.
Date: January 21, 1994
Creator: Boyd, S.; Newmark, R. & Wilt, M.
System: The UNT Digital Library
Fourth and Fifth Amendment issues raised by Chemical Weapons Convention inspections (open access)

Fourth and Fifth Amendment issues raised by Chemical Weapons Convention inspections

The Chemical Weapons Convention (CWC) offers a unique challenge to the United States system of constitutional law. This discussion is about the Fourth and Fifth Amendment issues raised by the CWC and about how federal implementing legislation can allow verification inspections to take place in the United States under the Chemical Weapons Convention while remaining in compliance with the Constitution. By implementing legislation, the author means a federal statute that would be enacted separately from Senate approval of the Convention itself. Although implementing legislation is a relatively unusual accompaniment to a treaty, it will be necessary to the CWC, and the Administration has submitted a bill that was under consideration in the last Congress and presumably will be reintroduced early next year. The Fourth and Fifth Amendment problems posed by the CWC arise from the verification inspection scheme embodied in the treaty. The CWC depends heavily on on-site inspections to verify compliance with its key requirements. These include destroying all chemicals weapons stockpiles and bringing potential chemical weapons precursors under international control. The Convention contains four distinct kinds of inspections: systematic inspections of chemical weapons storage and destruction facilities, routine inspections of various declared facilities, challenge inspections, and a variant …
Date: October 21, 1994
Creator: Tanzman, E. A.
System: The UNT Digital Library
Carbon dioxide cleaning pilot project (open access)

Carbon dioxide cleaning pilot project

In 1989, radioactive-contaminated metal at the Rocky Flats Plant (RFP) was cleaned using a solvent paint stripper (Methylene chloride). One-third of the radioactive material was able to be recycled; two-thirds went to the scrap pile as low-level mixed waste. In addition, waste solvent solutions also required disposal. Not only was this an inefficient process, it was later prohibited by the Resource Conservation and Recovery Act (RCRA), 40 CFR 268. A better way of doing business was needed. In the search for a solution to this situation, it was decided to study the advantages of using a new technology - pelletized carbon dioxide cleaning. A proof of principle demonstration occurred in December 1990 to test whether such a system could clean radioactive-contaminated metal. The proof of principle demonstration was expanded in June 1992 with a pilot project. The purpose of the pilot project was three fold: (1) to clean metal so that it can satisfy free release criteria for residual radioactive contamination at the Rocky Flats Plant (RFP); (2) to compare two different carbon dioxide cleaning systems; and (3) to determine the cost-effectiveness of decontamination process in a production situation and compare the cost of shipping the metal off site for …
Date: January 21, 1994
Creator: Knight, L. & Blackman, T. E.
System: The UNT Digital Library
Toward improved photon-atom scattering predictions (open access)

Toward improved photon-atom scattering predictions

Photon-atom scattering is important in a variety of applications, but scattering from a composite system depends on the accurate characterization of the scattering from an isolated atom or ion. We have been examining the validity of simpler approximations of elastic scattering in the light of second-order S-matrix theory. Partitioning the many-body amplitude into Rayleigh and Delbrueck components, processes beyond photoionization contribute. Subtracted cross sections for bound-bound atomic transitions, bound pair annihilation, and bound pair production are required in anomalous scattering factors for: (1) convergence of the dispersion integral; (2) agreement with predictions of the more sophisticated S-matrix approach; (3) satisfying the Thomas-Reiche-Kuhn sum rule. New accurate tabulations of anomalous scattering factors have been prepared for all Z, for energies 0--10,000 keV, within the independent particle approximation (IPA) using a Dirac-Slater model of the atom. Separately, experimental atomic photoabsorption threshold information has been used to modify these IPA predictions for improved comparison with experiment.
Date: October 21, 1994
Creator: Kissel, L.
System: The UNT Digital Library
PMESH: A parallel mesh generator (open access)

PMESH: A parallel mesh generator

The Parallel Mesh Generation (PMESH) Project is a joint LDRD effort by A Division and Engineering to develop a unique mesh generation system that can construct large calculational meshes (of up to 10{sup 9} elements) on massively parallel computers. Such a capability will remove a critical roadblock to unleashing the power of massively parallel processors (MPPs) for physical analysis. PMESH will support a variety of LLNL 3-D physics codes in the areas of electromagnetics, structural mechanics, thermal analysis, and hydrodynamics.
Date: October 21, 1994
Creator: Hardin, D.D.
System: The UNT Digital Library
Geomechanics investigations in support of the large block test at Fran Ridge, Nye County, Nevada. (open access)

Geomechanics investigations in support of the large block test at Fran Ridge, Nye County, Nevada.

The Yucca Mountain Site Characterization Project is investigating the Topopah Spring Tuff at Yucca Mountain, Nevada for its suitability as a host rock for the disposal of high level nuclear wastes. The Lawrence Livermore National Laboratory is planning a large block test (LBT) to investigate coupled thermal-mechanical-hydrological and geochemical processes that may occur in the repository near-field environment.
Date: July 21, 1994
Creator: Blair, S.C.; Berge, P.; Kansa, E.; Lin, Wunan & Roberts, J.
System: The UNT Digital Library
Hybrid electric vehicles TOPTEC (open access)

Hybrid electric vehicles TOPTEC

This one-day TOPTEC session began with an overview of hybrid electric vehicle technology. Updates were given on alternative types of energy storage, APU control for low emissions, simulation programs, and industry and government activities. The keynote speech was about battery technology, a key element to the success of hybrids. The TOPEC concluded with a panel discussion on the mission of hybrid electric vehicles, with a perspective from industry and government experts from United States and Canada on their view of the role of this technology.
Date: June 21, 1994
Creator: unknown
System: The UNT Digital Library
Safe venting of ``red oil`` runaway reactions (open access)

Safe venting of ``red oil`` runaway reactions

Calorimetry testing of Tri-n-butyl phosphate (TBP) saturated with strong nitric acid was performed to determine the relationship between vent size and pressure buildup in the event of a runaway reaction. These experiments show that runaway can occur in an open system, but that even when runaway is induced in the TBP/HN0{sub 3} system, dangerous pressure buildup will be prevented with practical vent size.
Date: December 21, 1994
Creator: Paddleford, D. F. & Fauske, H. K.
System: The UNT Digital Library