Virtual Interpersonal Touch and Digital Chameleons

We studied the characteristics of hand touch with a mechanical device that approximated a handshake, and we then examined the effect of handshake mimicry on assessment of a partner. Two participants interacted with a force-feedback joystick that recorded each of their hand movements individually. The two participants then greeted one another by feeling the recording of the other person’s movements via the force-feedback device. For each dyad, one of the participants actually received his or her own virtual handshake back under the guise that it was the other person’s virtual handshake. Results demonstrated three significant findings. First, for any given participant, a metric that took into account position, angle, speed, and acceleration of the hand movements correlated highly within individuals across two handshakes. Second, across participants, these metrics demonstrated specific differences by gender. Finally, there was an interaction between gender and mimicry, such that male participants liked people who mimicked their handshakes more than female participants did. We discuss the implications of these findings and relate them to theories of social interaction.

DYNAMIC INTERACTION OF PRICE AND DESIGN QUALITY FOR PRODUCTS WITH CONVEX PRODUCTION COSTS

Price and design quality define value for customers and are often used by firms to position products in the marketplace. Setting price and quality level on a new product for the first time and making appropriate changes over time to these variables to reflect changing conditions in the market requires careful coordination of design, manufacturing, and marketing variables. We present a control theoretic model to study the complex interaction among price, quality, and cost during the life cycle of a product. Our model considers the major design-manufacturing-marketing tradeoffs and helps determine optimal pricing, design quality, and production strategies in a dynamic environment with convex production costs.     

Family structure and income inequality in families with children, 1976 to 2000

Using 24 years of data from the March supplements to the Current Population Survey and detailed categories of family structure, including cohabiting unions, I assess the contribution of changes in family structure to the dramatic rise in family income inequality. Between 1976 and 2000, family structure shifts explain 41% of the increase in inequality, but the influence of family structure change is not uniform within this period or across racial-ethnic groups. In general, the estimated role of family structure change is inversely related to the magnitude of the changes in inequality. Furthermore, by including cohabitation, I find lower levels of total inequality and a weaker role for demographic shifts in family structure for trends in income inequality.     

A midwife program of newborn resuscitation

A very small proportion of newborns fail to establish a normal respiratory pattern without some assistance at birth and newborns requiring resuscitative measures at birth should have a skilled practitioner able to provide it. In this small hospital midwives felt unskilled in newborn resuscitation and paediatricians were not always immediately available. A stakeholder group gathered to discuss the problem. A training program was implemented that improved the skills, confidence and support of the attending midwife to resuscitate the newborn effectively. The aim was to improve the outcome for the infant whilst maintaining the mother's choice of birthing in a small local hospital close to family and friends.     

CHANGING MANUFACTURING STRATEGY

This paper demonstrates an approach to successfully managing change of manufacturing strategy. It first introduces the issues and management guidelines, and then describes how one company used this approach to achieve dramatic benefits from changing its manufacturing strategy. A third part of the paper elaborates on how the company made the approach work.     

Urinary Excretion of Chromium Following Ingestion of Chromite-Ore Processing Residues in Humans: Implications for Biomonitoring

Biomonitoring programs for urinary chromium (Cr) typically attempt to evaluate occupational exposure via the inhalation route. This study investigated whether Cr can be detected in the urine of people following the ingestion of soils that contain relatively high concentrations of chromium in chromite ore processing residue (COPR). To evaluate the reasonableness of using urinary monitoring to assess environmental exposure, six volunteers ingested 400 mg of soil/day (low-dose group), two others ingested 2.0 g of soil/day (high-dose group) for 3 consecutive days, and one person ingested a placebo on each of 3 days. The soil and COPR mixture contained concentrations of total chromium (Cr) and hexavalent chromium [Cr(VI)] of 103 ± 20 and 9.3 ± 3.8 mg/kg, respectively. Therefore, the low-dose group ingested 41 μg Cr/day [including 3.7 μg Cr(VI)] and the high-dose group ingested 206 μg Cr/day [including 18.6 μg Cr(VI)] on each of 3 consecutive days. All urine samples were collected and analyzed individually for total Cr on the day prior to dosing, during the 3 days of dosing, and up to the first void 48 h after the last dose. No significant increases in urinary Cr excretion were found when background excretion data were compared with data following each of the 3 days of dosing or in daily mean urine concentrations of the high- vs the low-dose groups. It appears that Cr present in a soil and COPR mixture at Cr doses up to 200 μg/day is not sufficiently bioavailable for biomonitoring of urine to be informative. These results are consistent with previously published findings suggesting that incidental exposure to dusts and soils containing comparable levels of Cr will not result in increased concentrations of Cr in urine.     

Assembly Line Balancing Using Genetic Algorithms with Heuristic-Generated Initial Populations and Multiple Evaluation Criteria*

We use genetic algorithms (GA) to solve the assembly line balancing (ALB) problem. Inparticular, we show how this technique can be used to generate feasible line balances, improve upon solutions obtained by other heuristics reported in the literature, and utilizeany one or more evaluation criteria that can be expressed in functional form. The procedure is demonstrated with two examples: (1) intimating the improvement of heuristic-generated ALB solutions by including them in the GA initial population, and (2) the possibility of balancing assembly lines with multiple criteria and side constraints. These examples suggest that GA can be a powerful tool in ALB. To investigate the utility of GA on single-criterion problems, an experiment is conducted that compares both the GA approach and conventional heuristics. Results indicate that the GA solutions are significantly improved over the heuristic solutions under the conditions studied. It is also found that the presence of heuristic-generated conventional solutions in the GA initial population leads to statistically preferred results.