Design and control of warehouse order picking: A literature review

Research on warehouse design and performance evaluation: A comprehensive review

We review the OR/MS literature on supply chain disruptions in order to take stock of the research to date and to provide an overview of the research questions that have been addressed. We first place disruptions in the context of other forms of supply uncertainty and discuss common modeling approaches. We then discuss nearly 150 scholarly works on the topic, organized into six categories: evaluating supply disruptions; strategic decisions; sourcing decisions; contracts and incentives; inventory; and facility location. We conclude with a discussion of future research directions.

https://papers.ssrn.com/sol3/Delivery.cfm?abstractid=1689882

OR/MS Models for Supply Chain Disruptions: A Review

https://isiarticles.com/bundles/Article/pre/pdf/12098.pdf

Behavior in operations management: Assessing recent findings and revisiting old assumptions

We review the Operations Research/Management Science (OR/MS) literature on supply chain disruptions in order to take stock of the research to date and to provide an overview of the research questio...

OR/MS models for supply chain disruptions: a review

In "bucket brigade" manufacturing, such as recently introduced to the apparel industry, a production line has n workers moving among m stations, where each worker independently follows a simple rule that determines what to do next. Our analysis suggests and experiments confirm that if the workers are sequenced from slowest to fastest then, independently of the stations at which they begin, a stable partition of work will spontaneously emerge. Furthermore, the production rate will converge to a value that, for typical production lines, is the maximum possible among all ways of organizing the workers and stations.

A Production Line that Balances Itself

The primary challenge for an urban bus system is to maintain constant headways between successive buses. Most bus systems try to achieve this by adherence to a schedule; but this is undermined by the tendency of headways to collapse, so that buses travel in bunches. To counter this, we propose a new method of coordinating buses. Our method abandons the idea of a schedule and even any a priori target headway. Under our scheme headways are dynamically self-equalizing and the natural headway of the system tends to emerge spontaneously. Headways also become self-correcting in that after disturbances they reequalize without intervention by management or even awareness of the drivers. We report on a successful implementation to control a bus route in Atlanta.

https://www2.isye.gatech.edu/~jjb/papers/Bartholdi-Eisenstein-2011.pdf

A self-coördinating bus route to resist bus bunching

"Bucket brigades" are a way of sharing work on a flow line that results in the spontaneous emergence of balance and consequent high throughput. All this happens without a work-content model or traditional assembly line balancing technology. Here we show that bucket brigades can be effective even in the presence of variability in the work content. In addition, we report confirmation at the national distribution center of a major chain retailer, which experienced a 34% increase in productivity after the workers began picking orders by bucket brigade.

https://www2.isye.gatech.edu/~jjb/bucket-brigades/papers/OR2001_V49_5:710-719.pdf

Performance of Bucket Brigades When Work Is Stochastic

We describe all possible asymptotic behavior of "bucket brigade" production lines with two or three workers, each characterized by a constant work velocity. The results suggest wariness in interpreting simulation results. They also suggest a strategy for partitioning a workforce into effective teams to staff the lines.

Dynamics of Two- and Three-Worker Bucket Brigade Production Lines

We consider the partitioning of care types into wings from the perspective of a hospital administrator who wishes to optimize the use of a fixed number of beds that provide services for heterogeneous care types. The hospital administrator decides on the number of wings to form, the number of beds to allocate to each wing, and the set of care types to assign to each wing to maximize the total utility to the hospital. The administrator faces an inherent trade-off between forming large wings to pool demand and bed capacity, and forming specialized wings to focus on narrow ranges of care types. Specialized wings not only provide advantages from focused care but also allow the protection of beds for high-utility care types. We provide an optimization model for the wing formation decision and address the advantages of focus endogenously in our model. Using data from a large urban teaching hospital in the United States along with a national database, we report on a number of managerial insights. In particular, as the overall demand increases across all care types, wings are formed to reserve more beds for higher-utility types, which leads to higher overall hospital utility but also some disparity across types, such as increased hospital access for some and decreased access for others. Furthermore, overall bed occupancy decreases as the hospital is split into wings. However, if sufficient focus is attained, shorter lengths-of-stay associated with focused care may increase overall patient throughput. We also observe that when patients are willing to wait longer for admission, the hospital tends to form more wings. This implies that hospitals that garner longer waits can form more specialized wings and thereby benefit from focused care, whereas hospitals that cannot will tend to form fewer, if any, wings, choosing to pool demand and bed capacity.

Donald D. Eisenstein

Papers

A Production Line that Balances Itself

A self-coördinating bus route to resist bus bunching

Performance of Bucket Brigades When Work Is Stochastic

Dynamics of Two- and Three-Worker Bucket Brigade Production Lines

Managing Hospital Inpatient Bed Capacity Through Partitioning Care into Focused Wings