主催：計測自動制御学会 企画：離散事象システム部会
| 題目 | タスク処理時間が異なる生産システムのスケジューリング |
| 著者 | ○川田誠一，小柳愼仁郎（都立大） |
| 概要 | The scene transition net (STN) is one of modeling tools that can express discrete/continuous hybrid systems. In this paper, we present a multi-objective scheduling method for manufacturing systems including modules with variable processing time using the scene transition nets. Simulation results show that the proposed scheduling method can generate the excellent schedule for the multi-objective cost function. |
| 題目 | 即時発火活性が可解であるペトリネットのサブクラス |
| 著者 | ○太田 淳，辻 孝吉（愛知県立大） |
| 概要 | Petri nets under the earliest firing rule, where transitions must fire as soon as they become enabled, have equivalent modeling power to that of Turing machines. Consequently, most analytical problems including reachability, deadlock freedom, liveness and so on are expected to be undecidable for nets with general structures. In this paper it is shown that deadlock freedom and liveness of earliest firing extended dissynchronous choice nets are equivalent to those of the nets with the identical structure under the normal firing rule. Thus, decidabilities of these problems are derived for the nets. |
| 題目 | 大規模離散事象システムにおける言語と述語の分離可能性 |
| 著者 | ○潮 俊光（阪大），高井重昌（和歌山大），古川泰伸（阪大） |
| 概要 | We consider a class of large scale discrete event systems consisting of several subsystems which operate concurrently. The concept of ``separability'' plays a very fundamental role in both language based control and predicate based control. We investigate the relationship between separability in language based control and that in predicate based control. Moreover, we discuss the existence of nonbalanced decentralized state feedback |
| 題目 | LLPスーパバイザとELLスーパバイザの比較 |
| 著者 | ○高井重昌（和歌山大） |
| 概要 | Two on-line supervisory control schemes, the LLP (Limited Lookahead Policies) supervision and the ELL (Extension based Limited Lookahead policies) supervision, have been proposed by Chung et al. and Kumar et al., respectively, for discrete event systems. In general, the ELL supervisor is more permissive than the (conservative) LLP supervisor. In this paper, we present a necessary condition for the ELL supervisor to be strictly more permissive than the LLP supervisor. |
| 題目 | アンフォールディングを用いた離散事象システムのフィードバック制御について |
| 著者 | ○宮本俊幸，熊谷貞俊（阪大） |
| 概要 | Synthesis of feedback control logic for live and safe marked graph has been given by Holloway and Krogh. The method strongly depends on the structure of marked graphs, and thus it has not been extended to wider classes. This paper considers synthesis of a maximal permissive feedback control for a special condition by using unfoldings. Unfoldings has similar structure to the marked graphs. Transforming a PN to an unfolding allows us to apply the Holloway's approach to general bounded PN's. |