There are some research works for concurrency control techniques to reduce locking overhead for class hierarchy in OODBs as follows.

In this locking system, a round spring-loaded lock pin sits transversely across the width of the handle with enough protruding from each side to serve as a stud.

When in use, the Flywheel Lock engages a specially designed locking device into the notches on the flywheel to prevent accidental rotation and possible injury while servicing is under way.

Therefore this solution proposes three modes of locking:

Mortise cylinder locks have a pin tumbler locking mechanism in a cylinder.

Only authorized service or repair personnel could unlatch an airbag without damaging its locking pins and rendering if useless.

The locking feature is achieved via the locking sleeve.

Locking or unlocking is a one-hand operation with the Ultra Cam Lock collet-style drill holder.

The lock comprises a strong stainless steel locking unit, a six-foot security cable and two keys.

The NSSF says it is replacing the old locks with an improved lock with a better locking mechanism and a thicker braided-steel cable.

Each half of the lock surrounds the trigger with a 1-inch locking post connecting the halves.