How to Draw a Travel Time Curve of Explosion Observation

How to Draw a Planarization

In this thesis we study the problem of computing a straight-line representation of a planarization with a fixed combinatorial structure. By the results of Mnëv [Mnë88] and Shor [Sho91] this problem is as hard as the Existential Theory of the Reals (∃R-Complete). We present a heuristic called Geometric Planarization Drawing to compute a straight-line representation of a planarization. We take an...

How to draw a group?

A map is at the same time a group. To represent a map (that is, a graph drawn on the sphere or on another surface) we usually use a pair of permutations on the set of the \ends" of edges. These permutations generate a group which we call a cartographic group. The main motivation for the study of the cartographic group is the so-called theory of \dessins d'enfants" of Grothendieck, which relates...

How to draw a hexagon

Pictures of the G2(2) hexagon and its dual are presented. A way to obtain these pictures is discussed. 1. Introduction This paper presents pictures of the two classical generalised hexagons over the eld with two elements. Information on these generalised hexagons is employed so that the pictures make some properties of these hexagons obvious. Familiarity with the theory of generalised polygons ...

Sensor Distribution Design of Travel Time Tomography in Explosion

Optimal sensor distribution in explosion testing is important in saving test costs and improving experiment efficiency. Aiming at travel time tomography in an explosion, an optimizing method in sensor distribution is proposed to improve the inversion stability. The influence factors of inversion stability are analyzed and the evaluating function on optimizing sensor distribution is proposed. Th...

How to Draw the Minimum