In this study, we introduce a new type of surface curves called $D$-type curve. This curve is defined by the property that the unit Darboux vector $vec{W}_{0} $ of a surface curve $vec{r}(s)$ and unit surface normal $vec{n} $ along the curve $vec{r}(s)$ satisfy the condition $leftlangle vec{n} ,vec{W}_{0} rightrangle =text{constant}$. We point out that a $D$-type curve is a geodesic curve or an...

Implicitly or explicitly, designers always affect the lives and wellbeing of users and of society at large. This is true in a trivial sense, since products are meant to fulfill existing and conscious needs. But it is also true in a less obvious way, since designers also affect the lives of users because of the various influences products have on people’s behavior, attitudes and needs. Such infl...

We prove that every algebraic curve X/Q is birational over C to a Teichmüller curve. keywords: algebraic curve, mapping class group, Teichmüller curve, Veech group. MSC code: 32G15, 37D40.