Programming by demonstration is a promising approach to automatic robot programming, however methods are required to remove suboptimal actions that can be demonstrated by end users. In this paper we use the partial knowledge of Con guration Space (C-space) derived in previous work to remove suboptimal actions from a demonstration. Our idea is to use demonstrated paths to predict what regions in...

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This work is devoted to practical stability of a class of regime-switching diffusions. First, the notion of practical stability is introduced. Then, sufficient conditions for practical stability and practical instability in probability and in pth mean are provided using a Lyapunov function argument. In addition, easily verifiable conditions on drift and diffusion coefficients are also given. Mo...

Let K be a set of positive integers. A pairwise balanced design (PBD) of index unity B(K,l;v) is a pair (X/~) where X is a v-set (of points) and B is a collection of subsets of X (called blocks) with sizes from K such that every pair of distinct points of X is contained in exactly one block of~. A necessary condition for the existence of a PBD B({4,8},I;v) is v-0 or l(mod 4). It is shown that t...

We describe a method used to prove nonexistence of pairwise balanced designs. We determine the exact closure of all subsets K of the set f3; 4