Pub. online:21 Nov 2025Type:Research ArticleOpen Access
Journal:Informatica
Volume 36, Issue 4 (2025), pp. 875–902
Abstract
In this paper, we consider the multi-Weber problem with polyhedral barriers. For this problem, a set of obstacles are introduced where travelling or placement is prohibited, which makes the distance metric non-convex and requires constructing a special graph for calculating the distances between pairs of points. For obtaining the global solution of the problem, we build a branch and bound algorithm with pruning criteria based on dividing clients into groups and analysing them separately. We have managed to obtain global solutions to several multi-Weber with polyhedral barriers problem size instances which to our knowledge have not been reported before.
Journal:Informatica
Volume 27, Issue 2 (2016), pp. 299–322
Abstract
We propose a heuristic global optimization technique which combines combinatorial and continuous local search. The combinatorial component, based on Reactive Search Optimization, generates a trajectory of binary strings describing search districts. Each district is evaluated by random sampling and by selective runs of continuous local search. A reactive prohibition mechanisms guarantees that the search is not stuck at locally optimal districts.
The continuous stochastic local search is based on the Inertial Shaker method: candidate points are generated in an adaptive search box and a moving average of the steps filters out evaluation noise and high-frequency oscillations.
The overall subdivision of the input space in a tree of non-overlapping search districts is adaptive, with a finer subdivision in the more interesting input zones, potentially leading to lower local minima.
Finally, a portfolio of independent CoRSO search streams (P-CoRSO) is proposed to increase the robustness of the algorithm.
An extensive experimental comparison with Genetic Algorithms and Particle Swarm demonstrates that CoRSO and P-CoRSO reach results which are fully competitive and in some cases significantly more robust.
Journal:Informatica
Volume 8, Issue 3 (1997), pp. 425–430
Abstract
In this paper we are concerned with global optimization, which can be defined as the problem of finding points on a bounded subset of Rm, in which some real-valued function f(x) assumes its optimal value. We consider here a global optimization algorithm. We present a stochastic approach, which is based on the simulated annealing algorithm. The optimization function f(x) here is discrete and with noise.
Journal:Informatica
Volume 2, Issue 2 (1991), pp. 248–254
Abstract
In well-known statistical models of global optimization only values of objective functions are taken into consideration. However, efficient algorithms of local optimization are also based on the use of gradients of objective functions. Thus, we are interested in a possibility of the use of gradients in statistical models of multimodal functions, aiming to create productive algorithms of global optimization.
Journal:Informatica
Volume 1, Issue 1 (1990), pp. 71–88
Abstract
In the paper the global optimization is described from the point of an interactive software design. The interactive software that implements numeric methods and other techniques to solve global optimization problems is presented. Some problems of such a software design are formulated and discussed.