Apparatus shears foreign matter that might entangle propellers and related structures on a moving vessel by action of a blade rotating with the propeller that cooperates with a non-rotating blade held close to the rotating blade. Specifically, techniques are provided for changing the ownership of data in a shared-nothing database dynamically, based on factors such as which node would be the most efficient owner relative to the performance of a particular operation. A method of assembling such a coupler head is furthermore described. The computer system also identifies text for the section. The sentence partition procedure separates the prototype sentence pattern into a plurality of sentence pattern components.