Performance Evaluation of Pathfinding Algorithms

Pathfinding is the search for an optimal path from a start location to a goal location in a given environment. In Artificial Intelligence pathfinding algorithms are typically designed as a kind of graph search. These algorithms are applicable in a wide variety of applications such as computer games, robotics, networks, and navigation systems. The performance of these algorithms is affected by several factors such as the problem size, path length, the number and distribution of obstacles, data structures and heuristics. When new pathfinding algorithms are proposed in the literature, their performance is often investigated empirically (if at all). Proper experimental design and analysis is crucial to provide an informative and non- misleading evaluation. In this research, we survey many papers and classify them according to their methodology, experimental design, and analytical techniques. We identify some weaknesses in these areas that are all too frequently found in reported approaches. We first found the pitfalls in pathfinding research and then provide solutions by creating example problems. Our research shows that spurious effects, control conditions provide solutions to avoid these pitfalls

Photoredox reactions of methylene blue on zinc oxide

729-732Photoreduction of methylene blue (MB+) at 366 nm (3.4 eV) in a heterogeneous medium containing ZnO (band separation = 3.2 eV) has been carried out. In oxygen-free media the product has been found to be leuco-MB which is fully converted into MB+ on air oxidation. An analysis of the results shows that Zno is the absorber and negligible light absorbed by MB+ cannot explain the observed conversions. Concentration of ZnO in the medium plays a more important role at higher concentrations of MB+. Also reaction extent decreases with increase in dye concentration but at low concentrations it is proportional to dye concentration. A unique feature of the reaction is that it is quenched by the product. Photoreduction is more efficient in solvents of high dielectric and in solvents with easily available hydrogens. Different samples of ZnO prepared from different salts behave differently in this photoreduction due to different reflectance and absorbance characteristics of these samples. A mechanism explaining the observed data and consistant with the known features of such systems have been proposed