In this paper, we define X-slant helix in Euclidean 3-space and we obtain helix, slant helix, clad and g-clad helix as special case of the X-slant helix. Then we study Darboux, tangential darboux developable surfaces and their singular points. Especially we show that the striction lines of these surfaces are singular locus of the surfaces.

Fibers composed of type I collagen triple helices form the organic scaffold of bone and many other tissues, yet the energetically preferred conformation of type I collagen at body temperature is a random coil. In fibers, the triple helix is stabilized by neighbors, but how does it fold? The observations reported here reveal surprising features that may represent a new paradigm for folding of ma...

Abstract While the Triple Helix and Quadruple models are popular in innovation studies, relations between them have not been addressed extensively literature. There diverse interpretations of helix empirical studies that apply them, but these sometimes deviate from original theses models. Such a situation can confuse newcomers to field terms which model their research. We discern cause this res...

Ukraine is suffering from low level of innovation activities and widening gap between the industry and research institutions, both in government and higher education sectors. This is reflected in shrinking of R&D financing, declining share of a number of graduates in natural sciences and engineering and some other indicators. Orientation on development of traditional industries of the national ...