Simulation and optimization of a new waste remediation process

In the development of large scale technologically advanced projects and procedures, it is often necessary to project the life cycle cost elements of a full production system based upon test results from a much smaller prototype facility. This paper describes an application of simulation to characterize equipment and facilities for a large-scale vitrification plant, based upon available results, expert opinion, and classical cost estimating techniques. This study improves the understanding of the vitrification process and reduced cost uncertainties. Further, it details how optimization was incorporated in modeling the minimum additive waste stabilization blending process to reduce the cost of additives and provide a more rigorous estimate of overall system cost.     

Effects of Exogenous and Endogenous Distracters on Immediate and Long‐Term Recall in Toddlers

We explored the role that exogenous and endogenous competitors for attention play in infants’ abilities to encode and retain information over a 6‐month period. Sixty‐six children visited the laboratory at 15 months, and 32 returned for a second visit at 21 months. Children observed models of conventional‐ relation and enabling‐relation action sequences. Half the children were distracted by a “Mister Monkey” mechanical toy during the conventional‐relation sequence, while the other half was distracted during the enabling‐relation sequence. The Early Childhood Behavior Questionnaire indexed endogenous factors at both ages. Immediate postmodel production of target actions indexed encoding efficiency, and 6‐month production of target actions indexed long‐term recall. The exogenous distracter impacted encoding efficiency (i.e., immediate recall), but not long‐term recall. Endogenous factors (i.e., temperament) were primarily associated with long‐term recall. Of special interest was our finding that endogenous factors, especially surgency, moderated the effect of the exogenous distracter. It appears that when learning conventional‐relation sequences in the presence of exogenous distracters, surgency mobilizes attentional resources toward the learning objective; however, when learning enabling‐relation sequences under the same conditions, surgency either boosts the saliency of the distracters or boosts children’s susceptibility to them.     

Exact and resampling probability values for the Piccarreta nominal–ordinal index of association

Exact, resampling, and Pearson type III permutation methods are provided to compute probability values for Piccarreta's nominal–ordinal index of association. The resampling permutation method provides good approximate probability values based on the proportion of resampled test statistic values equal to or greater than the observed test statistic value.     

Vulnerable African American Seniors: The Challenges of Aging in Place

American Community Survey data are used to develop typologies of the generational dynamics and living arrangements of the estimated 1.6 million African American older adult households who will likely encounter the most difficulty aging in place. Policy recommendations and strategies are offered to address the specific barriers and challenges that must be overcome in order for these older adults to successfully live out their lives in their homes and community.     

Adult youth workers’ conceptions of their work in an under-resourced community in the United States

This study examined adult workers’ conceptions of their work with youth in a large, underserved, urban region in the northeastern United States. Drawing on qualitative interviews with 18 youth workers from various organizations, affiliated with a community coalition focused on substance abuse prevention, we explored how adults viewed their role of working with youth. We were particularly interested in whether these workers saw youth empowerment and collaboration with youth for community change as part of their role. Our data suggested that while workers in this study were very supportive of youth, the support and actions they provided were on behalf of rather than with them and that, in general, partnering with youth for community change was not a part of what they envisioned their work to be. While a few of the adults attempted to work more collaboratively with youth, they were clearly in the minority.     

Modern and Postmodern Career Theories: The Unnecessary Divorce

Postmodern approaches to career counseling are becoming increasingly popular. Part of the impetus for the postmodern view has involved perceived problems in the assumptions and application of the modern approach. Two points of view have emerged: (a) the modern and postmodern approaches are incompatible, and the postmodern approach is superior to the modern approach and (b) the modern and postmodern approaches are compatible, each with specific benefits and limitations, and individual needs and cost‐effectiveness should govern the decision of which approach to use. Key issues to examine in this discussion are standardized career assessment, aggregate career information, matching, and cost‐effectiveness.     

Factors Affecting Alcohol Purchase Decisions and Expenditures: A Sample Selection Analysis by Ethnicity in Malaysia

Heckman’s sample selection model was applied to data from the Malaysian Household Expenditure Survey 2004/2005 to examine the factors influencing the likelihood of purchasing and the amount spent on alcohol in Malaysia. Results of the marginal effects suggest that while socio-demographic factors are important determinants of household purchase decisions and expenditure levels on alcohol in Malaysia, the effects vary across ethnic groups. Specifically, although education had a significant but modest impact in reducing the probability of alcohol purchases and expenditure levels among ethnic Chinese households, this effect was not evident among the ethnic Indians and other races. While increasing household size lowered the likelihood of purchasing alcohol and its expenditure levels for all ethnic groups, the reinforcing effects of both income and gender were relevant only for ethnic Chinese and Indian households. Last, urban Indian households were less likely to purchase alcohol and spend less compared to rural Indian households.

Do Expectations Make the Difference? A Look at the Effect of Educational Expectations and Academic Performance on Enrollment in Post-Secondary Education

Despite the belief that education is the great equalizer in American society, previous research has shown that the promises of educational accomplishments have not extended equally across racial/ethnic groups as minorities are less likely to matriculate to post-secondary education. Using data from the second follow-up and base year of the Educational Longitudinal Study of 2002, we examine the impact of GPA and students’ expectations on the probability of post-secondary enrollment. Specifically, we assess the impact of low achievement on the probability of post-secondary enrollment across racial/ethnic groups. We find that low achievement acts as less of a barrier to post-secondary enrollment for minority students compared with their non-Hispanic white counterparts. Moreover, students with high expectations and low achievement experienced higher probabilities of post-secondary enrollment than students with low expectations and high achievement. Given that minority students are said to have higher expectations, we examine whether the interaction of expectations and achievement varies across racial/ethnic groups. While we did not uncover racial/ethnic differences for low-achieving students with high expectations, our findings suggest that expectations help propel all low-achieving students with high expectations into post-secondary enrollment. This study moves beyond the traditional black/white differences by including a number of racial/ethnic groups.     

Relationships Between (Step)Parents and Adult (Step)Children: Explaining Influences on Life Satisfaction and Marital Quality

The purpose of this study was to examine important influences of adult (step)children’s relationships with their biological fathers, biological mothers, and resident stepparents on their life satisfaction and marital quality and the moderating role of stepparent gender. The sample (N = 215) was from Wave 3 of the National Survey of Families and Households (NSFH). Results illustrate that (a) biological mothers and stepparents positively influenced life satisfaction among adult (step)children regardless of stepfamily type; and (b) that the influence of parent–child relationship quality on the adult child’s marital quality did vary as a function of stepfamily type. Specifically, there was a positive link between current stepmother–child relationship quality and the focal child’s current marital quality. The opposite link was found for those reared in stepfather households.