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Port-Hamiltonian system theory is a well-known framework for the control of complex physical systems. The majority of port-Hamiltonian control design methods base on an explicit input-state-output port-Hamiltonian model for the system under consideration. However in the literature, little effort has been made towards a systematic, automatable derivation of such explicit models. In this paper, we present a constructive, formally rigorous method for an explicit port-Hamiltonian formulation of multi-bond graphs. Two conditions, one necessary and one sufficient, for the existence of an explicit port-Hamiltonian formulation of a multi-bond graph are given. We summarise our approach in a fully automated algorithm of which we provide an exemplary implementation along with this publication. The theoretical and practical results are illustrated through an academic example., Comment: 15 pages, 1 figure

A study is described of heuristic devices useful in learning both native and second languages. The study concerns particularly the means used by very young students (second and third graders) in vocabulary acquisition and in the establishment of semantic relationships. It was of concern to verify if (1) the children would use their knowledge of verbal relationships, such as synonyms and antonyms, to discover the semantic consequences of certain types of relationships; and (2) if they would have recourse to original heuristic procedures, that is those not yet introduced by the instructor. Some reflections are offered on activities in the domains of word definition, derivation and polysemia. Mastery of the more formal means of definition seems to be linked to the child's developmental stages, and there is a noticeable relationship between grammatical categories and the means used by the children to define the word. In the matter of derivation, the children discovered they could create new words by using prefixes and suffixes, and that they could verify their discovery by looking the words up in the dictionary. Because of the degree of abstraction involved in polysemia, the children's natural resources in this domain and in the use of homonyms were found to be limited. The positive effects of the study concerned not only vocabulary increase but also teacher-student relationships and the children's own participation in the learning process. (AMH)