Design of Intelligent Information Support Systems for Human-Operators of Complex Plants

Complex equipment of an industrial plant subject to control, large body of information flows, complexity of control problems, lack of time available to make a decision, etc. are the reasons which lead to a number of cases to contradiction of human-operator control capabilities and actual control problem requirements. Within such a problem, a natural way out is to design an intelligent information support system (IISS) which would be able to assist the human-operator to implement the complex industrial plant control functions. These functions are to involve operative mode control of automatic systems, monitoring the systems performance, and prediction of the plant status, both within normal and abnormal situations. Involving such an IISS into control process enables one to decrease the human-operator load, to increase the human-operator performance, and to increase the plant performance reliability. Copyright © 2008 IFAC 1. TASKS AND STRUCTURE OF IISS To design an IISS, one is to integrate as whole conventional algorithmic techniques of control of complex industrial plants and an intelligent technology paradigm. Within the scopes, the algorithmic techniques are used in cases when corresponding knowledge is of the concise, sharp-cut, welldefined, formalized form, while the artificial intelligence techniques are applied to a number of mildly formalized problems arising under control of complex dynamic systems. These problems are characterized by imperfection, ambiguity, ignorance of initial information, and by use of corresponding rules of the information processing. In accordance to the above reasoning, the IISS tasks may be related to (Byvaikov et al., 2002, Byvaikov et al., 2006, Poletykin et al., 2002): assessment of the current status (situation); prediction of the plant behavior under normal operating mode; prediction of abnormal events expansion; elaborating and assessing possible human-operator control actions as well as selecting the best control actions, etc. A feature of the IISS is its ability of behavior planning, adaptation, and learning. To implement the feature, the IISS is endued by a powerful hierarchical control structure. Within such a structure, at least the following three levels are of the most importance: the level of strategies, the level of tasks, and the level of components (modules, subsystems). The highest level, the level of strategies, determines ordering, implementing or stopping tasks solving. Also, the level organizes an interaction between the tasks. Provided that some tasks are selected at the level of strategies to be implemented, at the level of tasks it is determined which components are to function to solve the selected tasks. Finally, at the lower level, the level of components, the component function is controlled, with the components solving partial subtasks. In the IISS, the role of the hierarchical control arrangement is implemented by an intelligent monitor which is presented in fig. 1. The monitor controls the system performance; determines when and which tasks are to be implemented; implements functions of intelligent configuration to realize automatic design of a functional scheme of information processing at the level of components in accordance to the tasks arising during the plant performance; realizes interaction between the system components, human-operators, and data sources; controls data flows; coordinates local solutions obtained by local subsystems; simplifies the human-operator interaction with the system by coordinating assessment and rationale of the proposed solutions, finding out another solution variants, clarification and revising of solutions adopted earlier, assessment of solutions proposed by the humanoperators, obtaining reference information on events arising at the plant. Another important part of the intelligent monitor is a kernel which implements the lower level control of the system in its Proceedings of the 17th World Congress The International Federation of Automatic Control Seoul, Korea, July 6-11, 2008 978-1-1234-7890-2/08/$20.00 © 2008 IFAC 2162 10.3182/20080706-5-KR-1001.0676 entirety. Design of such a kernel is to insure its effective and predictable performance. Basic functions of the kernel are realization of interaction between the system components by use of a message transfer mechanism, and dispatching jobs in the system in order to ensure real-time performance. Plant Human-operators Environment Communication channels