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This book constitutes the refereed proceedings of the 8th International Conference on Machines, Computations, and Universality, MCU 2018, held in Fontainebleau, France, in June 2018.

The 9 revised full papers presented together with 5 invited talks were carefully reviewed and selected from numerous submissions. MCU explores computation in the setting of various discrete models (Turing machines, register machines, cellular automata, tile assembly systems, rewriting systems, molecular computing models, neural models, concurrent systems, etc.) and analog and hybrid models (BSS machines, infinite time cellular automata, real machines, quantum computing, etc.).

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Control Mechanisms for Array Grammars on Cayley Grids.- A Pleasant Stroll Through the Land of Distributed Machines, Computation, and Universality.- Sequential Grammars with Activation and Blocking of Rules.- The Language (and Series) of Hammersley-type Processes.- Minimizing Rules and Nonterminals in Semi-conditional Grammars: Non-trivial for the Simple Case.- Minimal Useful Size of Counters for (Real-Time) Multicounter Automata.- A Framework for (De)composing with Boolean Automata Networks.- An Extension of Interval-valued Computing Equivalent to Red-green Turing Machines.- Physical Computation and First-Order Logic.

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