Data World Blog

The Travelling Salesman Problem (TSP) is one of the most famous problems in computer science for studying optimization, the objective is to find a complete route that connects all the nodes of a network, visiting them only once and returning to the starting point while minimizing the total distance of the route. The problem of the traveling agent has an important variation, and this depends on whether the distances between one node and another are symmetric or not, that is, that the distance between A and B is equal to the distance between B and A, since in practice is very unlikely to be so. The number of possible routes in a network is determined by the equation: (𝒏−𝟏)! This means that in a network of 5 nodes the number of probable routes is equal to (5-1)! = 24, and as the number of nodes increases, the number of possible routes grows factorially. In the case that the problem is symmetrical the number of possible routes is reduced to half: ( (𝒏−𝟏)! ) / 𝟐 The complexity o

Experiments with ant species (Iridomyrmex humilis, Linepithema humile and Lasius niger) showed that there is an indirect communication between individuals through pheromones . The ants, on their way from the nest to the food source and vice versa, deposit pheromones in the soil forming a trail, which are able to smell the rest of the components of the colony. The greater the concentration on a path the greater the probability that an ant will follow that path. To test this fact, double-bridge experiments were designed, changing the relationship (𝑟 = 𝑙𝑙/𝑙𝑠 ) between the lengths of branches, being 𝑙𝑙 and 𝑙𝑠 are the lengths of the long and short branches, respectively. In the first experiment the nest was connected with the food source using two branches of same length, while in the second experiment the two branches were of different length. Fig.1 Bridge experiments: a) Branches of same length, r=1. b) Branches of different length, r= 2. In the first case the re