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The Journal for Vocational Special Needs Education

Description: This issue of the Journal for Vocational Special Needs focuses on the aging process and its effects on society and the workforce. Aging is the one experience that we all have in common. Individuals are expected to live longer in the future. Many will undoubtedly work beyond the traditional retirement age. This means that the composition of workers will be a blend of people, both young and old.
Date: 1998
Creator: Allen, Jeff M.; Sarkees-Wircenski, Michelle & West, Lynda L.
Partner: UNT College of Information

Voice Onset Time Characteristics of Selected Phonemes in Young and Old Male Speakers

Description: The purpose of the investigation was to compare mean voice onset time in young and old male subjects, as well as to examine variability of VOT productions with age for prevocalic bilabial, alveolar, and velar voiced and voiceless stop consonants. Forty-five Caucasion.males were divided equally into three.age groups. Ten tokens of six stimulus words were recorded and wide band spectrograms were made. Results of an analysis of variance revealed no significant differences in VOT with age when averages of the phonemes were used for analysis; however, a significant interaction between age and voiced phonemes was found when individual trials of phoneme productions were used for analysis.
Date: December 1985
Creator: Thomas, Kathy Wright
Partner: UNT Libraries

Solderability Study of Tin/Lead Alloy Under Steam-Aging Treatment by Electrochemical Reduction Analysis and Wetting Balance Tests

Description: Two types of solder samples, pins and through-holes were tested by SERA™ (Sequential Electrochemical Reduction Analysis) and Wetting Balance after various length of steamaging treatment. It was shown that after steam-aging, both types of specimen gave a similar electrochemical reduction curve, and solderabilty predictions made from SERA™ test agree with results obtained from Wetting Balance test on a qualitative base. Wetting balance test of pin samples after SERA™ test confirmed that SERA™ is a non-destructive testing method -- it even restored solderability. Comparison of electrochemical reduction behavior of samples under different treatment indicates that steam-aging can not reproduce exactly the effect of naturally atmospheric aging, and may not be the best artificial accelerating environment adopted.
Date: May 1993
Creator: Gao, Yang, 1966-
Partner: UNT Libraries

The Influence of Age on Public Sector Managerial Evaluations

Description: As the American population ages, the issues of aging and work have gradually come to the forefront. An older and increasingly diverse workforce has raised concerns over job performance, labor costs, and alternative work demands. At the same time, evidence indicates that older workers continue to experience extensive labor market problems due to false assumptions on the part of managers about the limiting effect of age on employee performance. The public sector's ability to respond to age-related issues in the workplace has largely been ignored by both public practitioners and researchers. This study addresses the questions of whether age negatively influences public personnel decisions, and if so, whether such influences adversely affect the treatment of older workers. The results of the survey indicate that public managers are susceptible to age bias when making personnel decisions.
Date: August 1993
Creator: McCaghren, Kathy L. (Kathy Lea)
Partner: UNT Libraries

Residual Cognitive Functioning of Elderly Males

Description: The Aronson Cognitive Residual Evaluation Scale (ACRES), designed to assess residual cognitive functioning with potential loss due to age or CNS disorder, was examined with a male subject group. The five ACRES subtests were administered to 45 elderly males. Results were compared with a previously reported subject group of 48 elderly females. Measures of the subjects' levels of independent functioning and their performances on selected Wechsler Memory Scale Revised (WMS-R) subtests were related to ACRES scores. Intercorrelations among ACRES subtests suggest that more than one cognitive factor is assessed. WMS-R subtests showed moderately significant correlations with ACRES for verbal tasks and for nonverbal tasks. Findings were discussed within a framework of lateralization of CNS functions.
Date: December 1990
Creator: Forté, Beverly K.
Partner: UNT Libraries

A Cross-Sectional Age Comparison of the Self-System Between Younger and Older Adults

Description: One of the most perplexing problems in the psychology of aging is whether there are characteristic changes in aspects of personality over the life course. This study attempts to address issues relating to changes in the self-system believed to take place as individuals grow older. Of particular interest is what age differences exist in the four components of the objective self described by Atchley (1982): the ideal self, self-concept, self-esteem, and self-evaluation. In order to examine the differences in these components of the self between younger and older adults the following predictions are made: 1) the ideal self for older adults will be more highly interrelated to their present self-concept than will that of younger adults, 2) issues of self-esteem will be more salient in older versus younger adults, and 3) issues of self-evaluation will be more salient in older than in younger adults. A questionnaire developed by Dittmann-Kohli, (1990) containing 30 incomplete sentences asking for fears, desires, goals, time perspective, self-evaluation, and self-description was given to 110 individuals ranging in age from 17-43 and 89 persons ranging in age from 61-96. Results indicate only partial support for age changes in the self-system.
Date: December 1992
Creator: Warner, Laura J. (Laura Jan)
Partner: UNT Libraries

Emotional Intelligence at Mid Life: A Cross Sectional Investigation of Structural Variance, Social Correlates, and Relationship to Established Personality and Ability Taxonomies

Description: Emotional Intelligence (EI) has been relatively unstudied after young adulthood. Yet there are a variety of reasons to expect that EI may be different at mid life than in young adulthood. Normative life experiences may lead to increases in EI, and as the array of different environments and experiences increases with age, one might expect greater individual differences in EI. Similarly, if EI is located somewhere at the intersection of personality and intelligence, as some have speculated, it may follow a course of structural differentiation similar to cognitive abilities. EI may be more closely linked to social variables such as loneliness and friendships at mid life, and its relation to established personality and ability factors such as the Big Five (Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness) and fluid and crystallized abilities may also vary with age. These hypotheses were investigated in samples of 292 young adults and 246 mid life adults, using the Schutte Self Report Emotional Intelligence Inventory, the NEO-Five Factor Personality Inventory, markers of crystallized and fluid ability from Horn's Crystallized/Fluid Sampler, and a variety of other measures. Mid life adults scored higher on overall EI scores, but evidenced no greater range of individual differences than did young adults. A series of exploratory and confirmatory factor analyses revealed no greater differentiation in the mid life sample either among dimensions of EI or between EI and personality and intelligence variables. Finally, EI appeared equally predictive of social variables in each sample. Results are discussed from the perspective of lifespan and aging literature on emotion, personality, and social functioning. Qualifications for the inference of age-related change in cross sectional designs are considered, along with advantages and disadvantages of factor-analytic and covariance structure modeling methodology. Implications, particularly for psychotherapy with each age group, are discussed.
Date: August 2005
Creator: Chapman, Benjamin P.
Partner: UNT Libraries

The Changing Use of Health Care Services by Unmarried Older Women, 1969 to 1975: Final Report to the NRTA-AARP Andrus Foundation

Description: Final report to the National Retired Teachers Association (NRTA)- American Association of Retired Persons (AARP) Andrus Foundation. This reports on a research study of the changing use of health care services by unmarried older women from 1969 to 1975.
Date: March 12, 1982
Creator: Martin, Cora A. & Eve, Susan Brown
Partner: UNT College of Public Affairs and Community Service

An overview of the US Department of Energy Plant Lifetime Improvement Program

Description: This paper provides a brief summary of the U.S. Department of Energy`s (USDOE`s) cooperative effort with the nuclear industry to develop technology to manage the effects of material degradation in systems, structures and components (SSCs) that impact plant safety or can significantly improve plant performance/economics and to establish and demonstrate the license renewal process. Also included are efforts to reduce decontamination/decommission costs, and reduce the uncertainty in long-term service-life decision making. During 1995, the Plant Lifetime Improvement (PLIM) Program was renamed the Commercial Operating Light Water Reactor (COLWR) Program activities are focused on sustaining the LWR option for domestic electricity generation by supporting operation of existing LWRs as long as they are safe, efficient, and economical. The status of the key projects is discussed in this paper.
Date: August 1, 1995
Creator: Moonka, A.K. & Harrison, D.L.
Partner: UNT Libraries Government Documents Department

Physician Utilization by a Black Aged Population: A Multivariate Investigation

Description: This investigation concerns the problem of current health care utilization by aged blacks. Utilizing Andersen's model, the volume and pattern of physician utilization associated with selected predisposing, enabling, and need variables is described for an aged population of 163 interviewed blacks residing in Census Tract 212, Denton, Texas, in 1972. None of the six socio-demographic, economic, or health status variables analyzed, through use of Somers' dyx, allowed substantial reduction .of error in predicting a physician visit in the past year. Representing need, selfrated health status was the best predictor variable. Its proportional reduction in error increased from 17 percent to 30 percent, for those with five to seven years education, and to 23 percent, for those reporting the least income.
Date: May 1974
Creator: Reban, Ann S.
Partner: UNT Libraries

Accelerated aging of EPDM and butyl elastomers

Description: This study was composed of three parts: a post cure study to optimize final properties of an ethylene-propylene-diene (EPDM) formulation, an accelerated aging study to compare the stress relaxation behavior of a butyl and an EPDM elastomer under compression, and a cursory evaluation of a new 70 Shore A EPDM. The optimum postcure for the EPDM was found to be 2 to 4 hours at 182{degrees}C in a vacuum. The EPDM was also shown to have superior aging characteristics compared to the butyl and is recommended for use instead of the butyl material. The physical properties for new 70 Shore A EPDM are satisfactory, and the stress relaxation behavior was only slightly inferior to the other EPDM.
Date: June 1, 1996
Creator: Wilson, M. H.
Partner: UNT Libraries Government Documents Department

Effect of thermal aging on mechanical properties of cast stainless steels

Description: A procedure and correlations are presented for predicting mechanical properties of cast stainless steels in service at temperatures <450{degrees}C from known material information. The ``saturation`` fracture properties of a cast stainless steel, i.e., the minimum values that would be achieved for the material after long-term service, are estimated from the chemical composition of the steel. Fracture properties as a function of time and temperature of service are estimated from the kinetics of embrittlement, which are also determined from chemical composition. The correlations successfully predict fracture toughness, Charpy-impact, and tensile properties of cast stainless steels from the Shippingport-, Ringhals-, and Gundremmingen-reactor components.
Date: March 1, 1995
Creator: Chopra, O.K.
Partner: UNT Libraries Government Documents Department

Development of a corrosion detection experiment to evaluate conventional and advanced NDI techniques

Description: The Aging Aircraft NDI Validation Center (AANC) was established by the Federal Aviation Administration Technical Center (FAATC) at Sandia National Laboratories in August of 1991. The goal of the AANC is to provide independent validation of technologies intended to enhance the structural inspection of aging commuter and transport aircraft. The deliverables from the AANC`s validation activities are assessments of the reliability of existing and emerging inspection technologies as well as analyses of the cost benefits to be derived from their implementation. This paper describes the methodology developed by the AANC to assess the performance of NDI techniques. In particular, an experiment being developed to evaluate corrosion detection devices will be presented. The experiment uses engineered test specimens, as well as complete aircraft test beds to provide metrics for NDI validation.
Date: December 31, 1995
Creator: Roach, D.
Partner: UNT Libraries Government Documents Department

Wire ageing with the TEA photocathode

Description: Recently several RICH protypes successfully tested a gaseous TEA photocathode. However, its wire ageing behavior is unknown. In principle, TEA is a more strongly bonded molecule than TMAE, and, as a result, one would expect better wire ageing behavior. This paper explores this question.
Date: June 1, 1996
Creator: Va`vra, J.
Partner: UNT Libraries Government Documents Department

Tracking accelerated aging of composites with ultrasonic attenuation measurements

Description: Composite materials are steadily replacing traditional materials in many industries. For many carbon composite materials, particularly in aerospace applications, durability is a critical design parameter which must be accurately characterized. Lawrence Livermore National Laboratory (LLNL) and Boeing Commercial Airplane Group have established a cooperative research and development agreement (CRADA) to assist in the high speed research program at Boeing. LLNL`s expertise in fiber composites, computer modeling, mechanical testing, chemical analysis and nondestructive evaluation (ND) will contribute to the study of advanced composite materials in commercial aerospace applications. Through thermo-mechanical experiments with periodic chemical analysis and nondestructive evaluation, the aging mechanisms in several continuous fiber polymer composites will be studied. Several measurement techniques are being studied for their correlation with aging. This paper describes through-transmission ultrasonic attenuation measurements of isothermally aged composite materials and their use as a tracking parameter for accelerated aging.
Date: October 1, 1996
Creator: Chinn, D.J.; Durbin, P.F.; Thomas, G.H. & Groves, S.E.
Partner: UNT Libraries Government Documents Department

Measurements of the diffusion of iron and carbon in single crystal NiAl using ion implantation and secondary ion mass spectrometry

Description: Classical diffusion measurements in intermetallic compounds are often complicated by low diffusivities or low solubilities of the elements of interest. Using secondary ion mass spectrometry for measurements over a relatively shallow spatial range may be used to solve the problem of low diffusivity. In order to simultaneously obtain measurements on important impurity elements with low solubilities, the authors have used ion implantation to supersaturate a narrow layer near the surface. Single crystal NiAl was implanted with either {sup 12}C or both {sup 56}Fe and {sup 12}C in order to investigate the measurement of substitutional (Fe) versus interstitial (C) tracer diffusion and the cross effect of both substitutional and interstitial diffusion. When C alone was implanted negligible diffusion was observed over the range of times and temperatures investigated. When both Fe and C were implanted together significantly enhanced diffusion of the C was observed, which is apparently associated with the movement of Fe. This supports one theory of dynamic strain aging in Fe alloys NiAl.
Date: December 31, 1998
Creator: Hanrahan, R.J. Jr.; Withrow, S.P. & Puga-Lambers, M.
Partner: UNT Libraries Government Documents Department

Chemometric Analysis of Two Dimensional Decay Data: Application to {sup 17}O NMR Relaxation Matrices

Description: The use of {sup 17}O NMR spectroscopy as a tool to investigate aging in polymer systems has recently been demonstrated. Because the natural abundance of {sup 17}O is extremely low (0.037%), the use of labeled {sup 17}O{sub 2} during the oxidation of polymers produces {sup 17}O NMR spectra whose signals arise entirely from the degradation species (i.e. signals from the bulk or unaged material are not observed). This selective isotopic labeling eliminates the impact of interference from the unaged material, cause (1) above. As discussed by Alam et al. spectral overlap between different degradation species as well as errors in quantification remains a major difficulty in {sup 17}O NMR spectroscopy. As a demonstration of the DECRA and CTBSA methods, relaxation matrices obtained from {sup 17}O NMR for model alcohol systems are evaluated. The benefits and limitations of these newly developed chemometric techniques are discussed.
Date: March 18, 1999
Creator: Alam, M.K. & Alam, T.M.
Partner: UNT Libraries Government Documents Department

High-Temperature Gas-Cooled Reactor Technology Development Program: Annual progress report for period ending December 31, 1987

Description: The High-Temperature Gas-Cooled Reactor (HTGR) Program being carried out under the US Department of Energy (DOE) continues to emphasize the development of modular high-temperature gas-cooled reactors (MHTGRs) possessing a high degree of inherent safety. The emphasis at this time is to develop the preliminary design of the reference MHTGR and to develop the associated technology base and licensing infrastructure in support of future reactor deployment. A longer-term objective is to realize the full high-temperature potential of HTGRs in gas turbine and high-temperature, process-heat applications. This document summarizes the activities of the HTGR Technology Development Program for the period ending December 31, 1987.
Date: March 1, 1989
Creator: Jones, J.E.,Jr.; Kasten, P.R.; Rittenhouse, P.L. & Sanders, J.P.
Partner: UNT Libraries Government Documents Department

Use of organic solderability preservatives on solderability retention of copper after accelerated aging

Description: Organic solderability preservatives (OSP`s) have been used by the electronics industry for some time to maintain the solderability of circuit boards and components. Since solderability affects both manufacturing efficiency and product reliability, there is significant interest in maintaining good solder wettability. There is often a considerable time interval between the initial fabrication of a circuit board or component and its use at the assembly level. Parts are often stored under a variety of conditions, in many cases not well controlled. Solder wettability can deteriorate during storage, especially in harsh environments. This paper describes the ongoing efforts at Sandia National Laboratories to quantify solder watability on bare and aged copper surfaces. Benzotriazole and imidazole were applied to electronic grade copper to retard aging effects on solderability. The coupons were introduced into Sandia`s Facility for Atmospheric Corrosion Testing (FACT) to simulate aging in a typical indoor industrial environment. H{sub 2}S, NO{sub 2} and Cl{sub 2} mixed gas was introduced into the test cell and maintained at 35{degrees}C and 70% relative humidity for test periods of one day to two weeks. The OSP`s generally performed better than bare Cu, although solderability diminished with increasing exposure times.
Date: February 1, 1997
Creator: Hernandez, C.L.; Sorensen, N.R. & Lucero, S.J.
Partner: UNT Libraries Government Documents Department

Nuclear power plant Generic Aging Lessons Learned (GALL). Main report and appendix A

Description: The purpose of this generic aging lessons learned (GALL) review is to provide a systematic review of plant aging information in order to assess materials and component aging issues related to continued operation and license renewal of operating reactors. Literature on mechanical, structural, and thermal-hydraulic components and systems reviewed consisted of 97 Nuclear Plant Aging Research (NPAR) reports, 23 NRC Generic Letters, 154 Information Notices, 29 Licensee Event Reports (LERs), 4 Bulletins, and 9 Nuclear Management and Resources Council Industry Reports (NUMARC IRs) and literature on electrical components and systems reviewed consisted of 66 NPAR reports, 8 NRC Generic Letters, 111 Information Notices, 53 LERs, 1 Bulletin, and 1 NUMARC IR. More than 550 documents were reviewed. The results of these reviews were systematized using a standardized GALL tabular format and standardized definitions of aging-related degradation mechanisms and effects. The tables are included in volume s 1 and 2 of this report. A computerized data base has also been developed for all review tables and can be used to expedite the search for desired information on structures, components, and relevant aging effects. A survey of the GALL tables reveals that all ongoing significant component aging issues are currently being addressed by the regulatory process. However, the aging of what are termed passive components has been highlighted for continued scrutiny. This document is Volume 1, consisting of the executive summary, summary and observations, and an appendix listing the GALL literature review tables.
Date: December 1996
Creator: Kaza, K. E.; Diercks, D. R.; Holland, J. W. & Choi, S. U.
Partner: UNT Libraries Government Documents Department

Structural and magnetic characterization of actinide materials

Description: This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The authors have successfully used neutron scattering techniques to investigate physicochemical properties of elements, compounds, and alloys of the light actinides. The focus of this work is to extend the fundamental research capability and to address questions of practical importance to stockpile integrity and long-term storage of nuclear material. Specific subject areas are developing neutron diffraction techniques for smaller actinide samples; modeling of inelastic scattering data for actinide metal hydrides; characterizing actinide oxide structures; and investigating aging effects in actinides. These studies utilize neutron scattering supported by equilibrium studies, kinetics, and x-ray diffraction. Major accomplishments include (1) development of encapsulation techniques for small actinide samples and neutron diffraction studies of AmD{sub 2.4} and PuO{sub 2.3}; (2) refinement of lattice dynamics model to elucidate hydrogen-hydrogen and hydrogen-metal interactions in rare-earth and actinide hydrides; (3) kinetic studies with PuO{sub 2} indicating that the recombination reaction is faster than radiolytic decomposition of adsorbed water but a chemical reaction produces H{sub 2}; (4) PVT studies of the reaction between PuO{sub 2} and water demonstrate that PuO{sub 2+x} and H{sub 2} form and that PuO{sub 2} is not the thermodynamically stable form of the oxide in air; and (5) model calculations of helium in growth in aged plutonium predicting bubble formation only at grain boundaries at room temperature. The work performed in this project has application to fundamental properties of actinides, aging, and long-term storage of plutonium.
Date: December 31, 1998
Creator: Cort, B.; Allen, T.H. & Lawson, A.C.
Partner: UNT Libraries Government Documents Department

Hanford Permanent Isolation Barrier Program: Asphalt technology development

Description: An important component of the Hanford Permanent Isolation Barrier is the use of a two-layer composite asphalt system, which provides backup water diversion capabilities if the primary capillary barrier fails to meet infiltration goals. Because of asphalt`s potential to perform to specification over the 1000-year design life criterion, a composite asphalt barrier (HMAC/fluid-applied polymer-modified asphalt) is being considered as an alternative to the bentonite clay/high density poly(ethylene) barriers for the low-permeability component of the Hanford Permanent Isolation Barrier. The feasibility of using asphalt as a long-term barrier is currently being studied. Information that must be known is the ability of asphalt to retain desirable physical properties over a period of 1000 years. This paper presents the approach for performing accelerated aging tests and evaluating the performance of samples under accelerated conditions. The results of these tests will be compared with asphalt artifact analogs and the results of modeling the degradation of the selected asphalt composite to make life-cycle predictions.
Date: November 1, 1994
Creator: Freeman, H.D. & Romine, R.A.
Partner: UNT Libraries Government Documents Department

Enhanced surveillance program annual report FY98. Dynamic behavior of Pu and U (intermediate strain rates) -- LA12

Description: The Kolsky-Hopkinson Bar Dynamic Test Facility in Building PF-4 at TA-55 recently became operational and the first series of plutonium samples from a baseline alloy were successfully tested on December 8, 1997 through the dedicated efforts of a large number of people in groups NMT-9, NMT-11, MST-8, NMT-5, and JCI. The Enhanced Surveillance Program provided the necessary support for this achievement. The Kolsky-Hopkinson bar is an instrument designed to measure the uniaxial compression stress-strain characteristics of special nuclear materials (SNM) in a glovebox environment at intermediate strain rates (typically 500 s{sup {minus}1} to 10,000 s{sup {minus}1}), over a wide temperature range (cryogenic up to near-melting temperatures), and up to strains of about 50% per test. Due to radiation contamination hazards, SNM samples are contained within a specially designed glovebox with only a small portion of the bar system. The uniaxial high-strain-rate deformation behavior of SNM materials is revealed by stress-strain-strain rate curves calculated from strain signals acquired by gauges on the pressure bars. The compressive stress-strain mechanical behavior of a range of weapons-relevant SNM materials (both baseline and stockpile-aged plutonium and enriched uranium), measured over a wide range of strain rates and temperatures, is necessary to support the development of predictive constitutive models and allows assessment of the mechanical response of SNM as a function of age, processing, and composition. Accurate constitutive material models are essential for simulating the high-rate deformation response of weapon materials. Most FY98 milestones and deliverables were successfully met or were partially completed on schedule. In the case of enriched uranium, testing began six months ahead of schedule. Upgrading the testing temperature capability took six months more than originally planned as a result of the highly formalized and rigorous design change plan (DCP) requirements at TA-55. Specimen availability continues to be a bottle-neck due to over-subscribed ...
Date: December 31, 1998
Creator: Blumenthal, W.R.
Partner: UNT Libraries Government Documents Department