In the development of a historical analysis on natural phenomenon electromagnetism, recurrently question appears subject: why does it take researchers about 2300 years to decipher, understand and then dominate apply electromagnetic for benefit human being? To answer this question, hypothesis Bacon's “idols” Bachelard's epistemological obstacle are presented. Both posed very correctly theory kno...

The grid obstacle representation, or alternately, ℓ1-obstacle representation of a graph G=(V,E) is an injective function f:V→Z2 and set point obstacles O on the points Z2 (where no vertex V has been mapped) such that uv edge in G if only there exists Manhattan path between f(u) f(v) avoiding f(V). This work shows planar graphs admit while exist some non-planar do not representation. Moreover, w...

In the future, it’s not difficult to image that we will often come across many autonomous mobile robots traversing densely populated place we live in. In such situation, because the autonomous mobile robots need to carry out their tasks in a place with unknown obstacles, the obstacle avoidance is one of the important functions of the robots. With a view to implementation of autonomous mobile ro...