Curve and skeleton based shape deformation In product design

In this report we present an intuitive curve and skeleton based approach for digital product modelling. Morphing-like deformations have been developed to allow for the evaluation of a larger set of alternative shapes compared to the set of shapes generated by the current modelling tools. The method helps designers to search in the product domain for alternative shapes in a straightforward way and eliminates the work-arounds. Through a slide-bar control, these alternative shapes are generated by the transformation of an initial shape into the target one by means of a suitable skeleton extraction transparent to the user and a user-defined profile curve for the target surface. The initial shape is abstracted by a skeleton and a distance function from the skeleton to the surface. For the target surface two categories have been considered, namely revolution-like and sweep-like surfaces. They are both defined through curves: an axis or a path and a profile. The user has to specify only the profile curve, as the axis or the path is represented by the skeletal curve extracted from the initial surface. The distribution of the morphing-like deformation is computed based on the skeletal curve, the distance function and the user-defined profile curve. The use of the skeleton guarantee the generated shapes belong to specific product domains and are therefore context-dependent

Jertfă și biruinţă : (în războiu cu Regimentul 50 Infanterie)

Focșani : Editura Librăriei Alex. N. Leon & Co, 191

Gold scavenged by bismuth melts: An example from Alpine shear-remobilizates in the Highis Massif, Romania

The original publication can be found at www.springerlink.comGold mineralization occurs in the Şoimuş Ilii vein, the main Cu prospect in the Highiş Massif, Western Apuseni Mts., Romania. The Highiş Massif is part of the Highiş Biharia Shear Zone, a 320–300 Ma Variscan greenschist belt, with a 114–100 Ma Alpine overprint. In Highiş, phyllonites enclose an igneous core consisting of an Early Permian basic complex intruded by Middle Permian granitoids. The vein is hosted within basalt hornfels at its contact with the 264 Ma Jernova granite. Gold is not only present as native gold, but also as jonassonite (ideally AuBi5S4). The latter occurs as inclusions 1–30 µm in size in chalcopyrite; microanalysis gives the empirical formulae Au1.02(Pb0.47Bi4.51)4.98S4. The two Au minerals are spatially associated with Bi–(Pb) sulfosalts (oversubstituted bismuthinite, cosalite) and sulfotellurides/selenides (ingodite, ikunolite and laitakarite) in blebs/patches, mainly hosted in chalcopyrite. This Au–Bi–Te association overprints an earlier, chalcopyrite-quartz assemblage, occurring as trails along discrete zones of brecciation that crosscut former mineral boundaries. Curvilinear and cuspate boundary textures within the blebs/patches suggest deposition in a molten form. Mineral associations in combination with phase relations indicate that the Au–Bi–Te association formed as a result of melting of pre-existing native Bi (and possibly sulfosalts) at 400 °C under sulfidation conditions. These melts incorporated Au, Pb, Te and S as they moved in the vein during shearing and were locked within dilational sites. Native Bi occurs as coarse aggregates along vein margins, but in the Au–Bi–Te association, it is present only as small droplets in shear gashes, never together with other Bi- and Au-minerals. The Bi-derived melts are part of an internal remobilizate which also includes chlorite and adularia. Minerals in the system Au–Bi–Te were deposited from a neutral low reducing fluid during Alpine shearing in the Early Cretaceous. The fluid also assisted solid-state mobilisation of chalcopyrite and cobaltite. This study illustrates the significant potential of Bi, a low melting-point chalcophile element (LMCE), to act as Au scavenger at temperatures as low as 400 °C.C. L. Ciobanu, N. J. Cook, F. Damian and G. Damia