‘The program has really changed me’

MSc, PDEng Po-Chun (Lionel) Yang, alumnus

Po-Chun Yang is an alumni of the Industrial Engineering program. He received his PDEng degree in 2009.

Improved logistical planning of supply chain for ASML

‘Some Industrial Engineering subjects were real eye-openers for me. I learned which factors you have to take account of in planning at a large company, something I just did not get in my Industrial Engineering study in Taiwan. The social skills I acquired were equally important. In Taiwan I was always very shy. Here I got some insight into my performance within a group and I learned to give presentations.

Various cultural backgrounds
In the first year we did different design projects as a team. This was a very valuable experience for me involving, as it did, students from various cultural backgrounds. I noticed how each culture brought a different behavior with it. In Taiwan people consider it normal to work overtime whereas the Dutch generally have a nine-to-five mentality. Their weekends tend to be free, and that is something I had to get used to.

Design project with ASML
My main project at ASML centered on the supply chain of parts for lithographic systems. Companies often use a Material Requirement Planning (MRP) system, checking what parts they need and estimating when they should be ordered to get the product finished in time. And when market demand changes, the planning of the materials in the MRP system is adjusted.

Some years ago demand for ASML high-tech systems declined. MRP planning meant that a lot of materials stacked up from the supply line could not be used straightaway. They had to be stored, an expensive exercise. I investigated how the logistical planning could be made more cost-efficient and then made a supply chain control framework, a way of better controlling the supply chain.

In complex equipment around eighty percent of the production costs are contained in about twenty percent of the parts. If purchasing of that critical twenty percent can be better planned, the total cost can be reduced. So I recommended making an initial selection of these critical parts, giving them greater focus. By splitting the production of them into various stages, whereby ASML had more communication and coordination with the respective suppliers, the supply line can become more efficient, flexible, transparent and less uncertain.

Actually, planning the whole supply chain is a combination of ‘make to order’ and ‘make to stock’ planning. Some parts you would like to have in permanent stock so you can get started immediately when an order comes in (‘make to stock’). This is good for performance to the customer but it does require a lot of storage space. Other parts you make when a customer provides specific requirements (‘make to order’). If the turnaround point in the planning of the supply line lies early in the manufacturing process at ‘make to order’, this can easily prompt a delay. This is even more likely the more uncertainties the production process has. On the other hand, you avoid purchases that are superfluous in retrospect. In the planning option, you have to take account of both cost-efficiency and performance.

I made a simulation model that calculates the consequences of a given choice for both aspects. The results of the simulation and the supply chain control framework function as a basis for subsequent projects geared to improving ASML’s planning system.

An experience that changed me
If I had opted to go to work in Taiwan after my studies, my professional life would have turned out quite differently. In Taiwan I often worked twelve hours a day for months on end, and sometimes even longer. This leaves little time for yourself. Here I have learned to enjoy life. Dealing with people from different cultures has been just as important as acquiring knowledge. It is an experience that has really changed me.’