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Estimate Trailer Carrier
Prepare Route Guide
Usage Timeout

[Truck-Load (TL)]
Prepare
Transportation Quote
[Single Package (SP)]
[Less than Truck-Load (LTL)]

Arrange Delivery Arrange Pickup
Appointment Appointment

Create Bill of Lading

Fig. 3.7 Applying restriction techniques to the carrier appointment process

between the current marking and the enabling markings for an OR-join, the active
projection technique might not be as significant. Hence, both techniques need to be
applied to achieve a more efficient OR-join evaluation.

3.5 Conclusion

Many workflow management systems and other process-aware information systems,
for example, Enterprise Resource Planning (ERP) systems, Customer Relationship
Management (CRM) systems, and Product Data Management (PDM) systems, have
problems supporting OR-join evaluation without imposing restrictions. Moreover,
diagramming notations such as BPMN, EPCs, etc. are not clear about the precise
semantics of the OR-join construct. It is surprising to see that standards such as
BPMN seem to ignore subtle issues such as the vicious circle and leave the interpre-
tation to users and tool developers. In this chapter, we have presented the semantics
for OR-join evaluation in the presence of cancelation regions, other OR-joins, and
(infinite) loops without adding structural restrictions. In the YAWL approach, reset
nets are used as a formal basis for OR-join analysis to support workflows with cance-
lation. A transformation function to map a YAWL net with OR-joins into a reset net
is provided. An OR-join evaluation algorithm which is based on the backward search