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...

objective: to determine the diagnostic value of blood cells surface markers in patients with acute appendicitis. methods: in this cross-sectional study, 71 patients who underwent appendectomy following a diagnosis of appendicitis were recruited during a one-year period. the patients were divided into two groups: patients with histopathologically confirmed acute appendicitis and subjects with no...

a method has been presented for finding the solution surface of the npde: u  c , bounded by a general space curve. the method is based on the geometric characteristics of the surface, and is called the “cone-slot method”. it has been shown that such a surface can be obtained by movement of a cone inside the slot formed by the boundary space curve. an algorithm has been suggested on the basis ...

co-channel interference is a major factor in limiting the capacity and link quality in cellular communications. as the co-channel interference is modeled by lognormal distribution, sum of the co-channel interferences of neighboring cells is represented by the sum of lognormal random variables (rvs) which has no closed-form expression. assuming independent, identically distributed (iid) rvs, the...

In this paper we consider Hugelschaffer cubic curves which are generated using appropriate geometric constructions. The main result of work is the mode explicitly calculating area egg-shaped part curve elliptic integrals. paper, also analyze surface for provide new forms formulae volume and part. Curves surfaces ovoid shape have wide applicability in aero-engineering construction, biologic impo...

The problem of reconstructing a shape from its sample appears in many scientific and engineering applications. Because of the variety in shapes and applications, many algorithms have been proposed over the last three decades, some of which exploit application-specific information and some of which are more general. We focus on techniques that apply to the general setting and have geometric and ...

Man-made objects usually exhibit descriptive curved features (i.e., curve networks). The curve network of an object conveys its high-level geometric and topological structure. We present a framework for extracting feature curve networks from unstructured point cloud data. Our framework first generates a set of initial curved segments fitting highly curved regions. We then optimize these curved ...