We investigate energetics and structure of circular and polygonal single wall carbon nanotubes (SWNTs) using large scale molecular simulations on NAS SP2, motivated by their unusual electronic and magnetic properties. The circular tori are formed by bending tube (n, n) whereas the polygonal tori are constructed by turning the joint of two tubes of (n, n), (n+1, n-1) and (n+2, n-2) with topologi...

This work studied the effect of additions of carbon dioxide to argon shielding gas on the weld shape and microstructure of ST14 steel in pulsed Nd: YAG laser welding. By additions of carbon dioxide up to 15%,the weld area and depth/width ratio decreases while rising of carbon dioxide up to 25% causes increasing of weld area and depth/width ratio. It is observed that the weld metal microstructur...

Parts manufactured to tolerances have variations in shape. Most previous work in robotic manipulation assumes that parts do not have shape variations. Orienting devices such as bowl feeders often fail due to variations in part shape. We study the effects of uncertainty in part shape on orienting to develop systems that can orient toleranced polygonal parts. We present a tolerance model in which...

Polygonal designs form a special class of partially balanced incomplete block designs. We resolve the existence problem for polygonal designs with various parameter sets and present several construction methods with blocks of small sizes.

This paper describes a dataow vertex detection algorithm for polygonal modeling of 2D contours. VLSI implementation by a parallel architecture is also proposed. This work is part of a real-time shape recognition system using polygonal models, presently under development.

In the applications such as scientific and medical visualization, highly detailed polygonal meshes are needed. Rendering these polygonal meshes usually exceeds the capabilities of graphics hardware. To improve rendering efficiency and maintain proper interactivity, the polygonal mesh simplification technique is commonly used to reduce the number of polygons of the mesh and to construct the mult...

Thawing permafrost in the Canadian Arctic tundra leads to peat erosion and slumping in narrow and shallow runnel ponds that surround more commonly studied polygonal ponds. Here we compared the methane production between runnel and polygonal ponds using stable isotope ratios, ¹⁴C signatures, and investigated potential methanogenic communities through high-throughput sequencing archaeal 16S rRNA ...

This article proposes a new heuristic (locally determined) algorithm for the triangulation between point sequences representing cross-sectional contours of a surface. Such point sequence is required to be the set of vertices of a polygon representing a Jordan curve and approximating the contour. The algorithm which is applied directly to the whole point sequence, is very simple since it is base...