Abstract：Query Reformulation Patterns in Cross-Device OPAC Search This paper studies the query reformulation patterns in different cross-device conditions by mining the transaction log of an OPACThe results show that PC-PC switching is the most important form of cross device and the cross-task pattern is the main quer Retrieval and IndexingQuerying in OPACOnline Public Access CatalogThis study explores query restructuring patterns across different devices by mining OPAC transaction logsThrough data mining techniquesthe study analyzes how users reorganize and modify their queries when switching between different devicesAdditionallythese restructuring patterns reflect changes in user search contexts and the impact of devices on queries