La méthode du discours : la philosophie

Au premier degré, cette étude se lit comme une réflexion sur le concept de méthode. L'examen des textes cartésiens permet de dégager les caractères de la méthode (comme Vordre volontaire, la médiation, la réflexivité), mais surtout ce qu'on peut appeler son « esprit ». Il tient tout entier, semble-t-il, dans la découverte - qui vaut invention - de la fécondité du principe : la pensée élaborée, en effet, aperçoit d'un même mouvement l'homogénéité du principe et de la fin, d'une part, l'homologie entre la pensée et l'Être, d'autre part. À un niveau plus profond, la transcendance de la méthode par rapport à ses règles (d'où le renversement du discours de la méthode en méthode du discours) conduit, dans un premier temps, à l'identifier avec la philosophie elle-même - appréhendée ici comme « commentaire de son principe » - dans un second temps à marquer, sous le rapport du modèle, la différence entre la philosophie et les sciences.As far as the literal meaning is concerned, this study can be read as a reflection on the concept of the method. The perusal of Descartes's texts allows to bring out the characteristics of the method (such as voluntary order, mediation, re flexibility), but especially what may be called its "spirit". It entirely lies, so it seems, in the discovery - which is as good as invention - of the potential of the principle : indeed, elaborate thought straightaway perceives the homogeneity of the principle and of the end, on the one hand, the homology between thought and Being, on the other hand. As far as the hidden meaning is concerned, the transcendence of the method with regard to its rules (from which the reversal of a discourse on method into a method on discourse) leads first to identify it with philosophy itself - in this instance considered as a "commentary on its principle" - subsequently to lay stress, from the point of view of the model, on the difference between philosophy and sciences

A simple and efficient feedback control strategy for wastewater denitrification

Due to severe mathematical modeling and calibration difficulties open-loop feedforward control is mainly employed today for wastewater denitrification, which is a key ecological issue. In order to improve the resulting poor performances a new model-free control setting and its corresponding "intelligent" controller are introduced. The pitfall of regulating two output variables via a single input variable is overcome by introducing also an open-loop knowledge-based control deduced from the plant behavior. Several convincing computer simulations are presented and discussed.Comment: IFAC 2017 World Congress, Toulouse, Franc

Le geste risque-tout : Écrire

Écrire est un geste retourné, qui décrit une volte dans l’ordre des opérations physico-techniques. Ce renversement proprement constituant rend raison – telle est ma thèse – de l’ambiguïté métaphysique qui s’attache à l’écriture : en tant qu’elle induit des effets mnémomorphes (hypomnèmata) gagés sur la dévitalisation de la mémoire et se développe comme système complexe depuis le pari risqué d’un qui-perd-gagne. Il lui faut accepter, comme le souligne explicitement Proust dans une page du Temps retrouvé, de perdre totalement et sans retour le monde de l’immédiateté sensible pour se vouer à l’effort héroïque de le « retrouver » en le reconstituant entièrement ; de se couper du monde holiste pour lui substituer son analyse, sans être jamais assurée que cette « catastrophe » scripturaire, ce point de rupture absolu de l’Évolution, sache être uniment et durablement productive.Among physiological and technical gestures, writing is essentially a reversed gesture. Hence the metaphysical ambiguity attached to writing, with its mnemomorphic/hypomnemata effects – as it bypasses memory and develops as a complex system based on a risky trade-off. Writing, as Proust suggests in Time regained, entirely relinquishes the world of sensible immediacy to devote itself heroically to win it back through reconstruction – it cuts itself from the world to replace it with an analysis of it, without ever knowing whether this “catastrophic” attempt will be successful

Stimulation of oxidative phosphorylation by electrophoretic K+ entry associated to electroneutral K+/H+ exchange in yeast mitochondria

AbstractThe effect of the addition of KCl, at constant osmolarity, was investigated on oxidative phosphorylation in isolated yeast mitochondria. KCl stimulated both respiration and ATP synthesis rates without changing the ATP/O ratio. KCl did not change the relationships between respiration rates and the protonmotive force. Since the K+/H+ exchange activity was active under these conditions, the stimulatory effect of respiration could be explained by the net proton entry caused by the electrophoretic K+ entry/electroneutral K+/H+ exchange cycle. On the other hand, K+ entry stimulated phosphate accumulation and transport under non-phosphorylating conditions and decreased the kinetic control by phosphate transport under phosphorylating conditions. Additionally, the stimulation of ATP synthesis strongly depended on the activity of phosphate transport. Taken together, these data showed that electrophoretic K+-entry and electroneutral K+/H+ exchange occurred in phosphorylating yeast mitochondria but did not promote any uncoupling between respiration and ATP synthesis