Solution : https://service.sap.com/sap/support/notes/733623 (SAP Service marketplace login required)
Key words : 
oracle backup/restore method, oracle exp/imp method, oracle exp/imp, oracle-specific methods, bw system copy, sap bi reason, oracle platform, oracle tool, operating system, sap support
Related Notes : 
       
| 617444 | Separate SCHEMA ID for database schema and tablespace name | 
| 325525 | Copying and renaming systems in a BW environment | 
| 184754 | Procedure after BW database copy |