Cellular Bucket Brigades on U‐Lines with Discrete Work Stations

It is challenging to maximize and maintain productivity of a U‐line with discrete stations under the impact of variability. This is because maximizing productivity requires assigning workers to suitable tasks and maintaining productivity requires sufficient flexibility in task assignment to absorb the impact of variability. To achieve this goal, we propose an operating protocol to coordinate workers on the U‐line. Under the protocol the system can be configured such that its productivity is maximized. Workers are allowed to dynamically share work so that the system can effectively absorb the impact of variability. Analysis based on a deterministic model shows that the system always converges to a fixed point or a period‐2 orbit. We identify a sufficient condition for the system to converge to the fixed point. Increasing the number of stations improves productivity only under certain circumstances. The improvement is most significant when the number of stations in each stage increases from one to two, but further dividing the U‐line into more stations has diminishing return. Simulations based on random work velocities suggest that our approach significantly outperforms an optimized, static work allocation policy if variability in velocity is large.     

A Systemic Approach to Racial Residential Patterns

This paper applied the model of Linear System of Action developed by Coleman (1992) to understand racial composition in neighborhoods from a systemic approach. The model had an advantage to consider how an individual household simultaneously maximizes all desirable neighborhood qualities with limited socioeconomic resources. The model generated relative values of socioeconomic resources and neighborhood qualities of each racial group in the exchange process. In addition, the model estimated a preference hierarchy of neighborhood qualities of each group. Results suggested that blacks and Asians in Canada tend to live in neighborhoods with higher proportions of their own groups because blacks may be steered away from predominantly white neighborhoods and Asians experience low returns on their socioeconomic resources in improving spatial contact with whites.