Engineering topics

Brave, Y.

Publications and source records attributed to Brave, Y..

2 records

NASA NTRS1991

Control of discrete event systems modeled as hierarchical state machines

The authors examine a class of discrete event systems (DESs) modeled as asynchronous hierarchical state machines (AHSMs). For this class of DESs, they provide an efficient method for testing reachability, which is an essential step in many control synthesis procedures. This method utilizes the asynchronous nature and hierarchical structure of AHSMs, thereby illustrating the advantage of the AHSM representation as compared with its equivalent (flat) state machine representation. An application of the method is presented where an online minimally restrictive solution is proposed for the problem of maintaining a controlled AHSM within prescribed legal bounds.

Brave, Y.↗

NASA NTRS1990

Stabilization of discrete-event processes

Discrete-event processes are modeled by state-machines in the Ramadge-Wonham framework with control by a feedback event disablement mechanism. In this paper, concepts of stabilization of discrete-event processes are defined and investigated. The possibility of driving a process (under control) from arbitrary initial states to a prescribed subset of the state set and then keeping it there indefinitely is examined. This stabilization property is studied also with respect to 'open-loop' processes and their asymptotic behavior is characterized. Polynomial time algorithms are presented for verifying various types of attraction and for the synthesis of attractors.

Brave, Y.↗