The present paper presents evolutions of spherical indicatrix of a space curve according to the quasi-frame. Then, some geometric properties of these surfaces constructed by evolutions have been obtained. At the end, illustrative examples of the spherical images of a space curve have been presented.

The present paper presents evolution of spherical indicatrix of a space curve according to the quasi frame in Minkowski 3-space. Some geometric properties such as fundamental forms and curvatures of the surfaces constructed by evolutions are obtained.

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In this paper, metallic structure and almost quadratic metric φ-structure are studied. Based on metallic (polynomial) Riemannian manifold, Kenmotsu quadratic metric manifold, cosymplectic quadratic metric manifold are defined and gave some examples. Finally, we construct quadratic φ-structure on the hypersurface M n of a locally metallic Riemannian manifoldM n+1 .

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In present paper, Double Minkowski Pythagorean Hodograph (DMPH) curves and type (3,0) Minkowski Pythagorean Hodograph (MPH) curves. Firstly, we obtained the conditions for a MPH curve to be a DMPH curve. Then, we examined these conditions in split quaternion form. Finally, a special class of seventh degree MPH curves is characterized and illustrative examples are given.

Tzitzeica curve is a special spatial curve, which introduced Gheorghe Tzitzeica in 1911. Gheorghe Tzitzeica defined this curve as follows; for a spatial curve ϕ, "if the ratio of its torsion τ and the square of the distance d from the origin to the osculating plane at an arbitrary point of the curve is constant, then this spatial curve is a Tzitzeica curve in Euclidean space." Moreover Gheorghe Tzitzeica defined a special surface which is named Tzitzeica surface in 1907. In this surface, the asymptotic lines of Tzitzeica surfaces with negative Gaussian curvature are Tzitzeica curves. Also, the ratio of its Gaussian curvature K and the distance d from the origin to the tangent plane at any arbitrary point of the surface is constant. In this paper, we study the Tzitzeica curve via q-frame in E^3. Firstly, we redefine the Tzitzeica curve q-frame in Euclidean 3- space. Then, it is obtained some conditions for the Tzitzeica curve as a spherical curve. Finally, we investigate harmonic vector cases of the Tzitzeica curve according to q- frame in Euclidean space.

In present paper, spatial Minkowski Pythagorean Hodograph (MPH) curves are characterized with Rational Rotation Minimizing Frames (RRMFs). We define Euler-Rodrigues Frame (ERF) for MPH curves and by means of this concept, we reach the definition of MPH curves of type (n, m). Expressing the conditions provided by these curves in the form of Minkowski-Hopf map that we define, it is aimed to establish a connection with the Lorentz force which occurs during the process of Computer Numerical Control (CNC) type sinker Electronic Discharge Machines (EDMs). This approach is reinforced by split quaternion polynomials. Finally, we give conditons satisfied by MPH curves of low degree to be type (n, m) and construct illustrative examples.