This paper describes the Subgradient Marching algorithm to compute the derivative of the geodesic distance with respect to the metric. The geodesic distance being a concave function of the metric, this algorithm computes an element of the subgradient in O(N log(N)) operations on a discrete grid ofN points. It performs a front propagation that computes the subgradient of a discrete geodesic dist...

Bacteria exist in a variety of groups of shapes, sizes, and single or multiple cell formations. In this paper, the level set shape reconstruction technique, the method of moments, and the marching cubes methods are integrated in the high frequency band for imaging three dimensional bacteria. The time step and the resolution of the marching cubes method are investigated to smooth the error funct...

The Fast Marching Method is a very popular algorithm to compute times-of-arrival maps (distances map measured in time units). Since their proposal in 1995, it has been applied to many different applications such as robotics, medical computer vision, fluid simulation, etc. Many alternatives have been proposed with two main objectives: to reduce its computational time and to improve its accuracy....

We present a method for calculating the boundary of objects from Discrete Indicator Functions that store 2material volume fractions with a high degree of accuracy. Although Marching Cubes and its derivatives are effective methods for calculating contours of functions sampled over discrete grids, these methods perform poorly when contouring non-smooth functions such as Discrete Indicator Functio...

abstract the production unit size is one of the effective factors in optimum uses of inputs. since optimum size is affected by the characters and economical conditions in each district, the studies for determining the optimum farm size should be done specially for each crop and each district. in this study tried to determine the optimum rice farm size in guilan province which is one of the most...

Three-dimensional (3D) volume data has become increasingly common with the emergence and wide availability of modern 3D image acquisition techniques. The demand for computerized analysis and visualization techniques is constantly growing to utilize the abundant information embedded in these data. This thesis consists of three parts. The first part presents methods of analyzing 3D volume data by...

In this paper, we study the hypersurface families with Smarandache curves in 4-dimensional Galilean space G 4 and give conditions for different to be parameter curve which generates is geodesic on a . Also, investigate three types of marching-scale functions one these hypersurfaces construct an example it.