The usefulness of the 3D Medial Axis (MA) is dependent on both the availability of accurate and stable methods for computing individual MA points and on schemes for deriving the local structure and connectivity among these points. We propose a framework which achieves both by combining the advantages of exact bisector computations used in computational geometry, on the one hand, and the local n...

An approximate analytical solution is obtained for hypersonic flow past a slender elliptic cone using second-order perturbation techniques in spherical coordinate systems. The analysis is based on perturbations of hypersonic flow past a circular cone aligned with the free stream, the perturbations stemming from the small cross-section eccentricity. By means of hypersonic approximations for the ...

Shock reflection is a fundamental phenomenon in studying compressible flow. Since Ernst Mach first studied the reflection phenomena of shock waves in 1878 [6] great amount of research works on such phenomena, mainly experiments and computations, was proceeded. In gas dynamics when a shock wave meets an obstacle in its propagation process the shock reflection occurs generally. There are various ...

This paper describes and demonstrates a graphical method of Skeletal Shock Graph, which is based on the shape or geometry of the object. Shock Graph is an abstraction of the skeleton of a shape onto a Directed Acyclic Graph (DAG) in which the skeleton points are labeled according to the local variation of the radius function at each point. A large image data base is created by using suitable im...

This paper describes a graphical method of Skeletal Shock Graph, which is based on the shape or geometry of the object. Shock Graph is an abstraction of the skeleton of a shape onto a Directed Acyclic Graph (DAG) in which the skeleton points are labeled according to the local variation of the radius function at each point. A large image data base is created by using suitable image acquisition t...

We experimentally study quasi-two-dimensional dilute granular flow around intruders whose shape, size, and relative impact speed are systematically varied. Direct measurement of the flow field reveals that three in-principle independent measurements of the nonuniformity of the flow field are in fact all linearly related: (1) granular temperature, (2) flow-field divergence, and (3) shear-strain ...

This paper presents a novel recognition framework which is based on matching shock graphs of 2D shape outlines, where the distance between two shapes is defined to be the cost of the least action path deforming one shape to another. Three key ideas render the implementation of this framework practical. First, the shape space is partitioned by defining an equivalence class on shapes, where two s...

We present three-dimensional, nonrelativistic, hydrodynamic simulations of bow shocks in pulsar wind nebulae. The simulations are performed for a range of initial and boundary conditions to quantify the degree of asymmetry produced by latitudinal variations in the momentum flux of the pulsar wind, radiative cooling in the postshock flow, and density gradients in the interstellar medium (ISM). W...