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111.
In this paper, we have successfully presented a fuzzy Petri net (FPN) model to design the genetic regulatory network. Based on the FPN model, an efficient algorithm is proposed to automatically reason about imprecise and fuzzy information. By using the reasoning algorithm for the FPN, we present an alternative approach that is more promising than the fuzzy logic. The proposed FPN approach offers more flexible reasoning capability because it is able to obtain results with fuzzy intervals rather than point values. In this paper, a novel model with a new concept of hidden fuzzy transition (HFT) to design the genetic regulatory network is developed. We have built the FPN model and classified the input data in terms of time point and obtained the output data, so the system can be viewed as the two-input and one output system. This method eliminates possible false predictions from the classical fuzzy model thereby allowing a wider search space for inferring regulatory relationship. The experimental results show the proposed approach is feasible and acceptable to design the genetic regulatory network and investigate the dynamical behaviors of gene network. 相似文献
112.
This paper focuses on the deadlock prevention problems in a class of Petri nets, systems of simple sequential process with resources, S3PR for short. By structure analysis, we propose an approach that can transform a plant net model into a weighted S3PR (WS3PR) that is behaviorally equivalent to the plant model. The WS3PR is made to be live by properly reconfiguring its weight distribution such that its all strict minimal siphons are self‐max'‐controlled. The resulting WS3PR can serve as a liveness‐enforcing Petri net supervisor for the plant model after removing some idle and operation places. A live controlled system can be accordingly obtained by synchronizing a plant model and the places whose weights are regulated. This research shows that a small number of monitors is obtained, leading to more permissive behavior of the controlled system. Examples are used to demonstrate the proposed concepts and methods. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
113.
This paper proposes a novel fault tolerant control (FTC) scheme for hybrid systems modeled by hybrid Petri nets (HPNs). The HPNs model consists of discrete and continuous PNs. The faults are represented by unobservable discrete transitions or the normal observable discrete transitions with abnormal firing time in discrete PNs. First, an observer‐based fault diagnosis method is proposed to estimate the marking in discrete places with unknown initial marking and diagnose the faulty behavior simultaneously. Then, an adaptive fault tolerant controller is designed to maintain the general mutual exclusion constraints (GMEC) of discrete PNs, and a scheme that adjusts firing speeds of continuous transitions is provided to maintain the optimality of continuous PNs. Finally, an example of an intelligent transportation system consisting of automated vehicles on a bridge is included to demonstrate the effectiveness of our developed techniques. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
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对数字家庭无线射频通信协议进行分解,给出协议各部分的流程。构造基于Petri网的通信协议模型,并在模型的基础上运用可达图方法分析协议Petri网模型的动态性质,从而验证协议的正确性,为进一步研究和应用该协议提供一种新的思路。 相似文献
118.
Implementing efficient scheduling and dispatching policies is a critical means to gain competitiveness for modern semiconductor manufacturing systems. In contemporary global market, a successful semiconductor manufacturer has to excel in multiple performance indices, consequently qualified scheduling approaches should provide efficient and holistic management of wafer products, information and manufacturing resources and make adaptive decisions based on real-time processing status to reach an overall optimized system performance. To cope with this challenge, a timed extended object-oriented Petri nets (EOPNs) based multiple-objective scheduling and real-time dispatching approach is proposed in this paper. Four performance objectives pursued by semiconductor manufacturers are integrated into a priority-ranking algorithm that serves as the initial scheduling guidance, and then all wafer lots will be dynamically dispatched by the hybrid real-time dispatching control system. A set of simulation experiments validate the proposed multiple-objective scheduling and real-time dispatching algorithm may achieve satisfactory performances. 相似文献
119.
Sylvie Troncale Author Vitae Jean-Paul Comet Author VitaeAuthor Vitae 《Pattern recognition》2009,42(4):562-566
The formalism of hybrid functional petri nets (HFPN) has proved its convenience for simulating biological systems. The drawback of the noticeable expressiveness of HFPN is the difficulty to perform formal verifications of dynamical properties. In this article, we propose a model-checking procedure for timed hybrid petri nets (THPN), a sub-class of HFPN. This procedure is based on the translation of the THPN model and of the studied property into real-time automata. It is applied to model enzymatic competitions existing in amphibian metamorphosis. 相似文献
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