The present paper studies a particular collection of classi cation problems, i.e., the classi cation of recursive predicates and languages, for arriving at a deeper understanding of what classi cation really is. In particular, the classi cation of predicates and languages is compared with the classi cation of arbitrary recursive functions and with their learnability. The investigation undertake...

In this paper, we propose a solution to McCarthy’s qualification problem [lo] based on the notion of possible worlds [3, 61. We begin by noting that existing formal solutions to qualification seem to us to suffer from serious epistemological and computational difficulties. We present a formalization of action based on the notion of possible worlds, and show that our solution to the qualificatio...

This paper provides a general treatment of privacy ampliication by public discussion , a concept introduced by Bennett, Brassard and Robert for a special scenario. Privacy ampliication is a protocol that allows two parties to distill a secret key from a common random variable that is only partially secret, i.e. about which an eavesdropper has some partial information , where the two parties gen...

The control of the cation composition formamidinium (FA), methylammonium (MA), and cesium (Cs) has been used to engineer significant improvements in organic–inorganic perovskite solar cells. However, thermal stability mixed-cation cells is not fully understood. In this work, we present results an experimental study double-cation perovskites [(FAPbI 3 ) 0.97 (MAPbBr 0.03 ] [(FAMA)-perovskite (PS...

Abstract Considering the importance of sub-monolayer transition metal oxides supported on another oxide in many industrial processes, with help a DFT + U approach, we provide information structural and electronic properties pure M 2 O 3 mixed MM ′O monolayers ( , ′ = Ti, V, Cr, Fe) an α -Al (0001) support. With their structure prolongation alumina corundum lattice, have non-equivalent surface i...