## 4 Application
### Existing Process for Responding to Supply Network Events  
The event response process must be clearly distinguished from the daily business process for demand planning between supply network and manufacturing. Although the daily business process controls the flow from company-wide demand planning to the release of lots in manufacturing and is therefore automated in many stages, the response to events from the supply network describes an escalation management and, therefore, includes various process steps that are carried out by humans. Both processes were modeled and analyzed in workshops with experts from various departments of different semiconductor manufacturers. Since the ACSN aims at optimizing the response to events from the supply network only an exemplary existing event response process is shown in Figure 8 and described below.  
If an event occurs in the supply network, it must first be detected and communicated. Although this communication process could be automated, it is often the supply network planner who is the recipient of this event-related communication. The supply network planner then investigates what effects the event has on quantities or delivery dates and then coordinates with the responsible production planner. Communication between these two can take place in personal conversations, by telephone, email or supported by manufacturing IT (cf. Section 3.4). The production planner then examines the possibility of changing quantities or delivery dates. To do so, he uses manufacturing data consisting of the current work in progress, the remaining lead times, the available capacity and certain master data to reach a decision on countermeasures to mitigate the consequences of the event occurred in the supply network. The experience knowledge of the production planner also influences this decision. Subsequently, the supply network planner receives feedback as to whether the change in quantity or delivery date can be implemented in manufacturing. Again, not necessarily in an automated manner.  
If the change in quantity or delivery date can be implemented, the production planner communicates certain countermeasures to adapt the schedule to the line manager in  
Figure 8: Exemplary process for responding to supply network events.  
manufacturing. Also, in this case, this communication can take place in personal conversations, by telephone, email or supported by manufacturing IT. The line manager then incorporates the adapted schedule into the manufacturing control system, typically a MES (cf. Section 3.4). It should be noted that communication between the production planner and the line manager here is usually only unidirectional. The line manager does not inform the production planner, in particular not with accuracy to single lots, whether the decision on an adapted schedule was appropriate regarding manufacturing. Thus, there is no systematic exchange of information to improve future decisions.  
Even though the semiconductor industry is without any doubt a high-tech industry, our workshop findings show that the escalation management process for events from the supply network in particular is often characterized by media discontinuities and manual decisions at many stages. These media discontinuities can lead to time-delayed communication and thus a shorter period of action for countermeasures. In addition, escalation management keeps people involved from focusing on daily business. Furthermore, due to the complex nature of the manufacturing process manual decisions can lead to unexpected behavior in manufacturing.