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On controllability conception for stochastic systems. (English) Zbl 0873.93076
Authors’ summary: The controllability notions for partially observed stochastic systems are defined. Their relation with complete and approximate controllabilities is shown. In particular, it is proven that the approximate controllability condition is necessary and the complete controllability condition is sufficient for the partially observed linear Gaussian control system to attain the arbitrarily small neighborhood of each point in the state space with probability arbitrarily closely to one.

MSC:
93E03General theory of stochastic systems
93B05Controllability