Let G = (V,E), V {1,2,...,n}, be a simple connected graph of order n, size m with vertex degree sequence d1 ? d2 ... dn > 0, di d(vi). The geometric-arithmetic topological index is defined as GA(G) i~j 2? didj/di+dj, whereas the coindex GA?(G) i~/j 2 didj/di+dj . New lower bounds for and in terms some parameters other invariants are obtained.

Mechanisms for fatigue crack closure under plane strain conditions have recently been identified at very low (near-threshold) stress intensities in terms of effects of excess corrosion deposits or fracture surface roughness in promoting premature closure of the crack. In the present paper, a geometric model is presented for crack closure induced by fracture surface roughness. This model specifi...

This paper presents research work in the area of analysis, extraction, and recognition of aesthetic information from architectural drawings. A computer-based system is developed that extracts the geometric and topological structure of a plan, detects wall-joints, and identifies axes of symmetry, hierarchies, proportions, and modularity within a plan.

This paper develops a simple bounding procedure for the optimal value of a posynomial geometric programming (GP) problem when some of the coefficients for terms in the problem’s objective function are estimated with error. The bound may be computed even before the problem is solved and it is shown analytically that the optimum value is very insensitive to errors in the coefficients; for example...

Buried infrastructures like sewers and water mains have to be checked for their current condition. Cracks are a strong indicator for the condition of a pipe. An affordable way to detect those cracks is to take images of the pipeline and use image processing techniques to detect cracks in these images. The methods used to accomplish this task are mathematical morphology and curvature evaluation ...

We study triangulated surface models with nontrivial surface metrices for membranes. The surface model is defined by a mapping r from a two-dimensional parameter space M to the three-dimensional Euclidean space R3. The metric variable gab, which is always fixed to the Euclidean metric δab, can be extended to a more general non-Euclidean metric on M in the continuous model. The problem we focus ...

This paper addresses the problem of path planning for a class of deformable volumes under fairly general manipulation constraints. The underlying geometric model for the volume is provided by a mass-spring representation. It is augmented by a realistic mechanical model. The latter permits the computation of the shape of the considered object with respect to the grasping constraints by minimizin...

Design, modeling, manufacturing and experimental analysis of a six degree freedom robot, suitable for industrial applications, has been described in this paper. The robot was designed on the assumption that, each joint has an independent DC motor actuator, with gear reduction and measuring sensor for angular joint position. Mechanical design of the robot was done using Mechanical Desktop and ma...