et *Cellule d'Intervention contre la Pollution dans les Alpes-Maritimes (C.I.P.Al.M.) TR. 2 -AeroportNice Cote d'Azur 06056 -Nice Cedex -France (Ra;u le 12 Decembre 1977)Resume La profondeur atteinte par l'herbier de Posidonia oceanica est le plus souvent fonction de la transparence des eaux littorales; toute alte'ration de celles-(processus d'eutrophisation par exemple) entraine une diminution de la quanttte* de lumiere recue au niveau d l'herbier profond qui regresse. Dans certains secteurs du littoral de Provence Cöte d'Azur, de nombreux temoignages attestent que l'herbier situe autrefois au delä de -30 metres ne se rencontre actuellement plus qu'aux environs de -25 metres.En utüisant les batiments de la Marine Nationale Frar^aise «TRITON» et «GRIFFON» (sous marin), les auteurs ont mis au point une methode permettant de cartographier avec precision la limite inferieure des herbiers de Posidonies. Cette möthode a e"t£ appliquee au cours de la campagne «Poseidon 76» oü plus de 23 kilometres de limite inferieure d'herbier situe* sur les cötes des Alpes maritimes (France) ont ete cartographies sur cinq cartes ä l'echelle l /5000. Les observations receuillies a bord du sous marin et celles realisees au cours de nombreuses plongees en Mediterranee occidentale ont permis aux auteurs de decrire trois types d'herbier profond. La densite des faisceaux foliaires, la Position des rhizomes et Topaisseur de la couche de rhizomes permettent de differencier ces trois types.Le type l correspond ä un herbier de faible densite (recouvrement parfois inferieur a 5%) dont les rhizomes sont en Position horizontale.Le type 2 correspond a un herbier de densite elevee (recouvrement superieur a 50%) dont les rhizomes sont en Position verticale. Ces rhizomes ne constituent pas encore une couche importante (< 20 cm).Le type 3 correspond ä un herbier de densite tres elevee (recouvrement superieur ä 75%) dont les rhizomes, en position verticale, constituent une couche epaisse (pouvant atteindre plus d'un metre). L*herbier profond peut s'arreter (limite inferieure) sous les trois formes docrites ci-dessus. Des hypotheses concernant les causes de Tarret de la Vegetation sont discutees. Une description des trois types d*herbier en voie de regression est igalement donnie.Ces premieres descriptions concernant Wtat de Therbier profond et Ia localisation de sä limite infSrieure sur des cartes precises permettront de mieux evaluer toute modification eventuelle de la Vegetation de Posidonia oceanica. Abstract Cartography and State of the Lowest Limit of the Posidonia oceanica Beds of the Alpes Maritimes (France) -Poseidon Campaign 1976The depth of the Posidonia beds nearly always depends on the transparency of the coastal waters; any change in this factor, for example due to eutrophication, results in an attenuation of the amount of light received by the deepest beds, which hinders the seagrass growth in certain areas of the Cöte d'Azur. There is sound evidence to show 0340-076X/78/

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Case-Based Reasoning (CBR) and interpolation tools are capable of providing solutions to unknown problems through the adaptation of other problems already solved. This paper proposes a generic approach using interpolation tool during the CBR-adaptation phase. Modelling was applied to EquiVox which attempts to design three dimensional representations of human organs according to external measurements. EquiVox follows the CBR-cycle and its adaptation tool is based on Artificial Neural Networks. The performances of this adaptation tool are evaluated and discussed. The results show that EquiVox fulfills the requirements of radiation protection experts who use such prototypes while also showing the limits of use of interpolation tools in CBR-adaptation. When adaptations are guided by experience and by the trial and error of experts, interpolation tools are well-fitted methods to automatically and quickly provide adaptation strategies and knowledge through training phases.

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In case of a radiological emergency situation involving accidental human exposure, a dosimetry evaluation must be established as soon as possible. In most cases, this evaluation is based on numerical representations and models of subjects. Unfortunately, personalised and realistic human representations are often unavailable for the exposed subjects. However, accuracy of treatment depends on the similarity of the phantom to the subject. The EquiVox platform (Research of Equivalent Voxel phantom) developed in this study uses Case-Based Reasoning principles to retrieve and adapt, from among a set of existing phantoms, the one to represent the subject. This paper introduces the EquiVox platform and Artificial Neural Networks developed to interpolate the subject's 3D lung contours. The results obtained for the choice and construction of the contours are presented and discussed.