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Salary Information for Nuclear Engineers and Health Physicists, October 1995

Description: Salary information was collected for October 1995 for personnel working as nuclear engineers and health physicists. The salary information includes personnel at the B.S., M.S., and Ph.D. levels with zero, one, and three years of professional work experience. Information is provided for utilities and non-utilities. Non-utilities include private sector organizations and U.S. Department of Energy contractor-operated facilities. Government agencies, the military, academic organizations, and medical facilities are excluded.
Date: October 15, 1995
Creator: Oak Ridge Institute for Science and Education
Partner: UNT Libraries Government Documents Department

Salary Information for Nuclear Engineers and Health Physicists, July 1996

Description: Salary information was collected for July 1996 for personnel working as nuclear engineers and health physicists. The salary information includes personnel at the B.S., M.S., and Ph.D. levels with zero, one, three, four to seven, and eight to ten years of professional work experience. Information is provided for utilities and non-utilities. Non-utilities include private sector organizations and U.S. Department of Energy contractor-operated facilities. Government agencies, the military, academic organizations, and medical facilities are excluded. In previous years the salary data have been collected for October. In 1996, the data were collected for July; thus, some caution must be exercised in making annual salary trend comparisons.
Date: July 15, 1996
Creator: Oak Ridge Institute for Science and Education
Partner: UNT Libraries Government Documents Department

Health Physics Enrollments and Degrees Survey, 2003 Data

Description: The survey includes degrees granted between September 1, 2002 and August 31, 2003. Enrollment information refers to the fall term 2003. Thirty-four academic programs at 33 different institutions were included in the survey universe with all responding (100% response rate). Several of the programs did not have any degrees awarded during the time period. Two programs included in the 2002 survey were either discontinued or out-of-scope and not included in 2003 survey.
Date: March 1, 2004
Creator: Oak Ridge Institute for Science and Education
Partner: UNT Libraries Government Documents Department

Nuclear Engineering Academic Programs Survey, 2002 Data

Description: The survey includes degrees granted between July 1, 2001 and June 30, 2002. Enrollment information refers to the fall term 2002. Thirty-five academic programs were in the survey universe and all responded (100% response rate). One of the 35 programs reported that it was discontinued after the 2001-2002 academic year. Also, two programs were discontinued after the previous academic year (2000-2001) and were not included in 2002 survey.
Date: October 1, 2003
Creator: Oak Ridge Institute for Science and Education
Partner: UNT Libraries Government Documents Department

Nuclear Engineering Academic Programs Survey, 2003

Description: The survey includes degrees granted between September 1, 2002 and August 31, 2003. Thirty-three academic programs reported having nuclear engineering programs during the survey time period and all responded (100% response rate). Three of the programs included in last year's report were discontinued or out-of-scope in 2003. One new program has been added to the list. This year the survey data include U.S. citizenship, gender, and race/ethnicity by degree level.
Date: March 1, 2004
Creator: Oak Ridge Institute for Science and Education
Partner: UNT Libraries Government Documents Department

Health Physics Enrollments and Degrees Survey, 2002 Data

Description: The survey includes degrees granted between July 1, 2001 and June 30, 2002. Enrollment information refers to the fall term 2002. Thirty-six academic programs at 35 different institutions were in the survey universe and all responded (100% response rate). Several of these programs did not have any degrees awarded during the time period. Five programs included in the 2001 survey were either discontinued or out-of-scope and not included in 2002 survey.
Date: October 1, 2003
Creator: Oak Ridge Institute for Science and Education
Partner: UNT Libraries Government Documents Department

U.S. Department of Energy Human Subjects Research Database (HSRD) A model for internal oversight and external transparency

Description: This poster introduces the Department of Energy (DOE) Human Subjects Research Database (HSRD), which contains information on all Department of Energy research projects involving human subjects that: are funded by DOE; are conducted in DOE facilities; are performed by DOE personnel; include current or former DOE or contract personnel.
Date: December 12, 2012
Creator: Oak Ridge Institute for Science and Education
Partner: UNT Libraries Government Documents Department

Bonding of WC with an iron aluminide (FeAl) intermetallic

Description: FeAl, which has high oxidation and sulfidation resistance, was shown to be thermodynamically compatible with WC. Calculations indicate that soly. of WC in liq. Fe-40at.%Al at 1450 C is about 2 at.%. Since liquid FeAl wets WC very well, the WC/FeAl system lends itself to liquid-phase sintering, resulting in close to theoretical densities. Almost fully dense cermets with 20.6 wt% FeAl binder were produced. With one-step infiltration, 98% dense cermets with only 7 wt% FeAl binder were fabricated. RT bend strengths and fracture toughness for WC-20.6 wt% FeAl reached 1680 MPa and 22 MPa{center_dot}m{sup 1/2}. Ductile binder fracture was observed on the fracture surfaces. Pores containing oxide inclusions were found, suggesting that improvements in processing are likely to further improve the mechanical properties. Insufficient process control may explain why WC/FeAlNi cermets did not show improved mechanical properties, although Ni strengthens FeAl. For WC bonded with FeAl, mechanical properties were measured at RT and 800 C. Bend strengths at 800 C in air increased with WC volume fraction, and fracture toughness were higher than at RT.
Date: August 1, 1996
Creator: Schneibel, J. H. & Subramanian, R.
Partner: UNT Libraries Government Documents Department

Study of the reactive element effect in ODS iron-base alumina-formers

Description: Iron aluminide (Fe{sub 3}Al) and FeCrAl compositions were dispersed with 15 different oxides in order to study the effect of oxygen- active dopants on high-temperature growth and adhesion of {alpha}- Al{sub 2}O{sub 3} scales. In these model-type, oxide dispersion strengthened (ODS) systems, the chemical effects of various cation dopants were compared to the baseline effect of an Al{sub 2}O{sub 3} oxide dispersion. By conducting isothermal and cyclic oxidation tests and by characterizing the oxidation product, effects on scale adhesion, growth rate and microstructure were evaluated. The dopants were categorized based on effectiveness in modifying the alumina scale. An Al{sub 2}O{sub 3} dispersion yielded some improvement in oxidation behavior apparently by strengthening the relatively weak substrate. However, the type of improvements in adhesion and change in growth mechanism associated with addition of reactive elements such as Y were not achieved. In general, due to the weaker substrate and the inherently faster interfacial void formation, the dispersions were less effective in ODS Fe{sub 3}Al than in ODS FeCrAl.
Date: May 1, 1996
Creator: Pint, B. A.
Partner: UNT Libraries Government Documents Department

The morphology of Al{sub 2}O{sub 3} scales: indicators of phase, growth mechanisms, and grain boundary segregation

Description: Advanced analysis over the past decade has resulted in increased understanding of the formation, growth, and adhesion of alumina scales. It is proposed that this can now be inferred from SEM images of the AL{sub 2}O{sub 3} scale morphology. The presence of bladelike grains is an indicator of metastable alumina phases and an outward growth mechanism. Large surface ridges indicate that the scale has transformed to {alpha}-Al{sub 2}O{sub 3}. A columnar grain structure is associated with an inward growth mechanism, while an equiaxed grain structure typically forms when both Al and O diffusion is occurring. Grain boundary segregation typically results in a fine grain size at the scale-gas interface. Examples are given from Ni- and Fe-base alumina formers ({beta}-NiAl, FeCrAl, iron aluminides) to illustrate these correlations. 5 figs, 35 refs, 1 tab.
Date: December 31, 1996
Creator: Pint, B. A.
Partner: UNT Libraries Government Documents Department

Wheel rolling constraints and slip in mobile robots

Description: It is widely accepted that dead reckoning based on the rolling with no slip condition on wheels is not a reliable method to ascertain the position and orientation of a mobile robot for any reasonable distance. We establish that wheel slip is inevitable under the dynamic model of motion using classical results on the accessibility and controllability in nonlinear control theory and an analytical model of rolling of two linearly elastic bodies.
Date: March 1, 1997
Creator: Shekhar, S.
Partner: UNT Libraries Government Documents Department

Neural net learning issues in classification of free text documents

Description: In intelligent analysis of large amounts of text, not any single clue indicates reliably that a pattern of interest has been found. When using multiple clues, it is not known how these should be integrated into a decision. In the context of this investigation, we have been using neural nets as parameterized mappings that allow for fusion of higher level clues extracted from free text. By using higher level clues and features, we avoid very large networks. By using the dominant singular values computed by Latent Semantic Indexing (LSI) and applying neural network algorithms for integrating these values and the outputs from other ``sensors,`` we have obtained preliminary encouraging results with text classification.
Date: March 1, 1996
Creator: Dasigi, V. R. & Mann, R. C.
Partner: UNT Libraries Government Documents Department

Wheel rolling constraints and slip in mobile robots

Description: It is widely accepted that dead reckoning based on the rolling with no slip condition on wheels is not a reliable method to ascertain the position and orientation of a mobile robot for any reasonable distance. The author establishes that wheel slip is inevitable under the dynamic model of motion using classical results on the accessibility and controllability in nonlinear control theory and an analytical model of rolling of two linearly elastic bodies.
Date: March 1, 1997
Creator: Shekhar, S.
Partner: UNT Libraries Government Documents Department

Allergy arising from exposure to airborne contaminants in an insect rearing facility: Health effects and exposure control

Description: In agricultural crop improvement, yield under various stress conditions and limiting factors is assessed experimentally. Of the stresses on plants which affect yield are those due to insects. Ostrinia nubilalis, the European corn borer (corn borer) is a major pest in sweet and field corn in the U.S. There are many ways to fight crop pests such as the corn borer, including (1) application of chemical insecticides, (2) application of natural predators and, (3) improving crop resistance through plant genetics programs. Randomized field trials are used to determine the effectiveness of pest management programs. These trials frequently consist of randomly selected crop plots to which well-defined input regimes are instituted. For example, corn borers might be released onto crop plots in several densities at various stages of crop development, then sprayed with different levels of pesticide. These experiments are duplicated across regions and, in some cases across the country, to determine, in this instance for example, the best pesticide application rate for a given pest density and crop development stage. In order to release these pests onto crop plots, one must have an adequate supply of the insect pest. In winter months studies are carried out in the laboratory to examine chemical and natural pesticide effectiveness, as well as such things as the role of pheromones in moth behavior. The advantage in field trials is that yield data can be garnered directly. In this country, insects are raised for crop research primarily through the US Department of Agriculture, in cooperation with public Land Grant Universities and, by the private sector agricultural concerns - seed companies and others. This study quantifies the airborne allergen exposure of persons working in a Land Grant University entomology lab were allergy to European corn borer was suspected.
Date: June 1, 1994
Creator: Wolff, D.
Partner: UNT Libraries Government Documents Department

Modeling and simulation of pulsed laser annealing and ablation of solid materials

Description: A previously developed one-dimensional (ID) computational model for heat flow and nonequilibrium phase change phenomena induced by pulsed-laser irradiation has been extended to two-dimensions. The 2D modeling focuses attention on the heat flow from localized sources embedded in an otherwise planar matrix. For example, nucleation events occurring in undercooled liquids such as molten Si formed by pulsed-laser melting of amorphous Si (a-Si) and inhomogeneous absorption due to randomly occurring defects in targets used for pulsed-laser ablation can be treated. Concepts introduced in the ID modeling, such as the state diagram and the state array are extended to 2D and refined. As an example of the calculations that are now possible, the laser-induced formation and propagation of buried liquid layers are followed in two dimensions for the case of a-Si on a crystalline silicon substrate. It is demonstrated how solid phase growth from individual nucleation sites gives rise to a nearly planar liquid layer propagating through the a-Si. Another example briefly addresses questions related to the early stages of the laser ablation of insulators such as MgO, where it is believed that the absorption of the laser radiation occurs at localized but extended regions of high concentrations of defects. The 2-D program has been rewritten for massively parallel machines such as the Intel Paragons in ORNL`s Center for Computational Sciences by one of us (CLL), thus allowing larger and more accurate calculations for complex systems to be carried out in reasonable times.
Date: April 1995
Creator: Liu, C. L. & Wood, R. F.
Partner: UNT Libraries Government Documents Department

Wheel rolling constraints and slip in mobile robots

Description: It is widely accepted that dead-reckoning based on the rolling with no-slip condition on the wheels is not a reliable method to ascertain the position and orientation of a mobile robot for any reasonable distance. The authors establish that wheel slip is inevitable under the dynamic model of motion using classical results on the accessibility and controllability in nonlinear control theory and an analytical model of rolling of two linearly elastic bodies.
Date: June 1, 1996
Creator: Shekhar, S.
Partner: UNT Libraries Government Documents Department

Toward a multi-sensor-based approach to automatic text classification

Description: Many automatic text indexing and retrieval methods use a term-document matrix that is automatically derived from the text in question. Latent Semantic Indexing is a method, recently proposed in the Information Retrieval (IR) literature, for approximating a large and sparse term-document matrix with a relatively small number of factors, and is based on a solid mathematical foundation. LSI appears to be quite useful in the problem of text information retrieval, rather than text classification. In this report, we outline a method that attempts to combine the strength of the LSI method with that of neural networks, in addressing the problem of text classification. In doing so, we also indicate ways to improve performance by adding additional {open_quotes}logical sensors{close_quotes} to the neural network, something that is hard to do with the LSI method when employed by itself. The various programs that can be used in testing the system with TIPSTER data set are described. Preliminary results are summarized, but much work remains to be done.
Date: October 1, 1995
Creator: Dasigi, V. R. & Mann, R. C.
Partner: UNT Libraries Government Documents Department

Iron free permanent magnet systems for charged particle beam optics

Description: The strength and astounding simplicity of certain permanent magnet materials allow a wide variety of simple, compact configurations of high field strength and quality multipole magnets. Here we analyze the important class of iron-free permanent magnet systems for charged particle beam optics. The theory of conventional segmented multipole magnets formed from uniformly magnetized block magnets placed in regular arrays about a circular magnet aperture is reviewed. Practical multipole configurations resulting are presented that are capable of high and intermediate aperture field strengths. A new class of elliptical aperture magnets is presented within a model with continuously varying magnetization angle. Segmented versions of these magnets promise practical high field dipole and quadrupole magnets with an increased range of applicability.
Date: September 3, 1995
Creator: Lund, S. M. & Halbach, K.
Partner: UNT Libraries Government Documents Department

Direct atomic resolution imaging of dislocation core structures in a 300 kV stem

Description: By employing the incoherent imaging technique of Z-contrast imaging in a 300kV STEM, the authors show that it is possible to provide directly interpretable, atomic resolution images of the sublattice in compound semiconductors. Using this approach, analysis of dislocations at an interface in the CdTe(001)/GaAs(001) system reveals unexpected core structures at Lomer dislocations.
Date: May 1, 1995
Creator: McGibbon, A. J. & Pennycook, S. J.
Partner: UNT Libraries Government Documents Department

Application of damage models in metal forming

Description: The development of damage models in the analysis of metal forming processes, to characterize the formability limits, is an important area of ongoing research. In this paper, two energy-based damage models for the simulation of crack initiation in metal forming processes are presented. The first one is an isotropic damage model with two damage variables. The second one is an anisotropic model with a damage characteristic tensor. The damage models are developed within the general framework of continuum thermodynamics for irreversible processes by identifying a proper set of internal variables together with their associated generalized forces. An approach is proposed to account for microcrack opening and closing. A viscoplastic regularization algorithm is used to take into account the strain rate effect and to improve numerical stability. Both models have been incorporated into the finite element code, LAGAMINE. The models were applied to simulations of upsetting of collar cylinders and nonisothermal hemispherical punch stretching. The results of the analyses were validated by comparing the finite element simulations with experimentally obtained data.
Date: June 1, 1995
Creator: Zhu, Y. Y. & Zacharia, T.
Partner: UNT Libraries Government Documents Department

Ionization delocalization and ALCHEMI of B2-ordered alloys

Description: Purpose of this paper is to demonstrate that the major assumption underlying the ALCHEMI formulation is justified: that the degree of ionization localization of an elemental shell can be accounted for by a linear coefficient; and to introduce a potential method, which would be applicable to B2-ordered alloys, of independently extracting the ratio of coefficients L{sub jk} necessary for delocalization correction. A Cr-doped FeAl alloy and a series of Fe-doped NiAl alloys with 0.25-12 at. % Fe were analyzed. Excellent linearity of the data substantiates the use of linear coefficients to model ionization localization. It was investigated whether the L{sub jk} acquired at a (110) systematics orientation could be accurately applied to ALCHEMI data acquired at (200).
Date: June 1, 1995
Creator: Anderson, I. M. & Bentley, J.
Partner: UNT Libraries Government Documents Department

Iron aluminide-titanium carbide composites: Microstructure and mechanical properties

Description: Composites of intermetallics and carbides (with binder contents less that 50 vol.%) are considered as potential candidates for applications requiring high wear resistance in corrosive environments. Intermetallics, especially aluminides, provide the corrosion resistance, and the high hardness of the carbide phase contributes to increased wear resistance of the composites. In this study, cost effective and simple processing techniques to obtain FeAl-TiC composites, over a wide range of binder volume fractions, are demonstrated. Binder volume fractions range from 0.15 to 0.7 (18 to 75 wt. % binder). Two techniques - liquid phase sintering of mixed powders and pressureless melt infiltration of TiC preforms was found to be very successful for obtaining fully dense composites with binder volume fractions from 0.15 to 0.3 (18 to 34 wt. %), whereas for higher binder contents liquid phase sintering of mixed powders was the best approach. Mechanical properties of these composites including the 3-point bend strength, fracture toughness and hardness are presented.
Date: September 1, 1996
Creator: Subramanian, R.; Schneibel, J. H. & Alexander, K. B.
Partner: UNT Libraries Government Documents Department

Dry spent fuel cask monitoring by {sup 252}Cf-source-driven frequency analysis measurements

Description: If developed, a nondestructive method would be useful for verifying canister contents without requiring the canister to be opened. This paper addresses the application of the {sup 252}Cf-source-driven frequency analysis measurements for verification of the fissile material content of sealed spent fuel canisters. The cross-power spectral density (CPSD) between the {sup 252}Cf source in an ionization chamber and external neutron detectors depends only on the induced fission rate in the fissile system and is independent of inherent sources. Thus the source-to-detector CPSD is ideal for determination of fissile material content of the spent fuel. This paper evaluates the application of this method to a 125 ton spent fuel canister that contained 21 pressurized-water reactor fuel elements. The results demonstrate that the fissile materials content of a sealed spent fuel canister could be obtained using the {sup 252}Cf frequency analysis method if calibration standards were available. The results also indicate that a measurement could be performed in less than a day for burnups up to 36 GWd/MTU and in less time for lower burnups.
Date: October 1, 1996
Creator: Valentine, T.E.; Mattingly, J.K. & Mihalczo, J.T.
Partner: UNT Libraries Government Documents Department