Biblio

Classification problems have been part of numerous real-life applications in fields of security, medicine, agriculture, and more. Due to the wide range of applications, there is a constant need for more accurate and efficient methods. Besides more efficient and better classification algorithms, the optimal feature set is a significant factor for better classification accuracy. In general, more features can better describe instances, but besides showing differences between instances of different classes, it can also capture many similarities that lead to wrong classification. Determining the optimal feature set can be considered a hard optimization problem for which different metaheuristics, like swarm intelligence algorithms can be used. In this paper, we propose an adaptation of hybridized swarm intelligence (SI) algorithm for feature selection problem. To test the quality of the proposed method, classification was done by k-means algorithm and it was tested on 17 benchmark datasets from the UCI repository. The results are compared to similar approaches from the literature where SI algorithms were used for feature selection, which proves the quality of the proposed hybridized SI method. The proposed method achieved better classification accuracy for 16 datasets. Higher classification accuracy was achieved while simultaneously reducing the number of used features.

In the last several decades digital images were extend their usage in numerous areas. Due to various digital image processing methods they became part areas such as astronomy, agriculture and more. One of the main task in image processing application is segmentation. Since segmentation represents rather important problem, various methods were proposed in the past. One of the methods is to use clustering algorithms which is explored in this paper. We propose k-means algorithm for digital image segmentation. K-means algorithm's well known drawback is the high possibility of getting trapped into local optima. In this paper we proposed brain storm optimization algorithm for optimizing k-means algorithm used for digital image segmentation. Our proposed algorithm is tested on several benchmark images and the results are compared with other stat-of-the-art algorithms. The proposed method outperformed the existing methods.

For most wireless sensor networks applications it is necessary to know the locations of all sensor nodes. Since sensor nodes are usually cheap, it is impossible to equip them all with GPS devices, hence the localization process depends on few static or mobile anchor nodes with GPS devices. Range based localization methods use estimated distance between sensor and anchor nodes where the quality of estimation usually depends on the distance and angle of arrival. Localization based on such noisy data represents a hard optimization problem for which swarm intelligence algorithms have been successfully used. In this paper we propose a range based localization algorithm that uses recently developed bat algorithm. The two stage localization algorithm uses four semi-mobile anchors that are at first located at the corners of the area where sensors are deployed and after that the anchors move to their optimal positions with minimal distances to sensor nodes, but with maximal viewing angles. Our proposed algorithm is even at the first stage superior to other approaches from literature in minimizing the error between real and estimated sensor node positions and it is additionally improved at the second stage.