Canadian Operational Research Society

Calgary Section

http://www.corscalgary.org/

PROFESSIONAL DEVELOPMENT SEMINAR

When: Noon to 1:30 PM, Thursday, February 15, 2007

Room 217

TransCanada Tower

450 - 1 Street SW

(See attached map)

SPEAKER

Dr. Van Enns

Associate Professor

Department of Mechanical and Manufacturing Engineering

University of Calgary

TOPIC

Comparing “Pull” Replenishment Systems under Capacity Constraints

Abstract:

In this presentation we will look at replenishment for a single capacity-constrained workstation. Set-up time is required when changing from one product to another. Specifically, a continuous-review reorder point system is compared with a single-card Kanban system.

The first issue to be examined is the differences in logic and information processing required for these two systems. Discussion will touch on the practical reasons why Kanban systems have become prevalent within manufacturing environments.

The second issue is how to compare systems under conditions in which each replenishment system is being operated optimally. This is not easy since there are multiple decision variables. As well there are multiple responses of interest, with tradeoffs between these. A methodology is developed in which simulation is used to collect data from which response surfaces can be generated. Response surface models and non-linear optimization are then used to determine optimal decision variable settings, based on the area under response trade-off curves. If further experimental data is then generated using these optimal settings, analysis of variance techniques can be used to make comparisons and study both main and interaction effects.

The third issue is the relative performance and differences in behaviour. It will be demonstrated that under time-varying demand reorder point systems outperform Kanban systems. As well, the impact of set-up time reduction will be examined, with and without re-optimization of the decision variables.

About the Speaker:

Dr. Van Enns is an Associate Professor in the Department of Mechanical and Manufacturing Engineering at the University of Calgary. His research and teaching interests lie in the areas of production planning and control, supply chain management, modelling manufacturing and logistics systems, and quality control. Prior to being at the U of C, he obtained BSc (Agricultural Engineering) and MBA degrees at the U of Manitoba and a PhD in Operations Management at the U of Minnesota. His background also includes 10 years of designing, testing and manufacturing agricultural equipment.