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Evolutionary algorithms show outstanding performance when they are applied to optimization problems with a few variables, i.e. problems with less than a hundred continuous variables. Large-scale global optimization with continuous variables is still a challenging task for a wide range of evolutionary algorithms. Their performance decreases when the number of variables increases because the search space grows exponentially. Classic evolutionary algorithms cannot find a good solution using the allocated resources. A cooperative coevolution approach is a good tool for increasing the performance of an optimizer in solving high-dimensional problems. The approach splits the objective vector into a predefined number of parts (subcomponents), and each part is optimized by its optimizer. This paper makes an effort to solve the problem of selecting the number of subcomponents. The paper represents a novel metaheuristic for solving optimization problems with a huge number of continuous variables. The suggested approach is based on the self-adaptive cooperation of algorithms and the cooperative coevolution approach. Each algorithm has a unique number of subcomponents. The metaheuristic automatically allocates resources between algorithms during the optimization process. Algorithms optimize the same population one by one. The proposed metaheuristic is titled COSACC, coordination of self-adaptive cooperative coevolution algorithms. We have evaluated the proposed algorithm on fifteen problems from the IEEE LSGO CEC'2013 benchmark. The study demonstrates that COSACC outperforms in average cooperative coevolution algorithms with the static number of subcomponents. Wilcoxon test has proven the results of numerical experiments. We have tested COSACC performance with other state-of-the-art metaheuristics, COSACC is a competitive approach. [ABSTRACT FROM AUTHOR]

The quadratic assignment problem is one of the most studied combinatorial optimization problems. Although many direct and heuristics methods exist for solving this problem, it takes a huge amount of time. Metaheuristics give an approximate solution in a feasible time. Therefore, we used a highly parallel iterated local search metaheuristic on a massively parallel graphics processing unit (GPU) to reduce the execution time. We utilized GPU spatial memory-global, local, constant, texture, and shared memory properties to further reduce the execution time. In this study, we found that using efficient utilization of GPU memory properties, and mixing different memory together we obtained better results from using only global memory. [ABSTRACT FROM AUTHOR]

In this paper, two new hybrid algorithms are proposed to solve global optimization problems. The first algorithm combines the sooty tern optimization algorithm with the arithmetic optimization algorithm, and the second algorithm combines the sooty tern optimization algorithm with the conjugate gradient method. The sooty tern optimization algorithm is a metaheuristic algorithm proposed by Dhiman and Kaur in 2019 Sooty migration and attack behaviors seabirds in nature were the primary inspiration for this algorithm. In this paper, this algorithm was hybridized using the arithmetic optimization algori thm and the conjugate gradient method, and the two algorithms were measured by applying them to 10 functions, and the results of the hybrid algorithms were very good compared to the original algorithm. [ABSTRACT FROM AUTHOR]

In Handwritten Character Recognition (HCR), interest in feature extraction has been on the increase with the abundance of algorithms derived to increase the accuracy of classification. In this paper, a metaheuristic approach for feature extraction technique in HCR based on Crow Search Algorithm (CSA) was proposed. Freeman Chain Code (FCC) was used as data representation. The main problem in representing a character using FCC is that the results of the extractions depend on the starting points that affected the route length of chain code. To solve this problem, the metaheuristic approach via CSA was proposed to find the shortest route length and minimum computational time for HCR. The performance measurements of the proposed CS-FCC extraction algorithm are the route lengths and computation times. The experiments on the algorithms are performed based on the chain code representation derived from established previous works of Center of Excellence for Document Analysis and Recognition (CEDAR) dataset which consists of 126 upper-case letter characters. Based on the result, the proposed CS-FCC obtained 1880.28 in term of route length and only needs 1.10 second to solve the whole character images. [ABSTRACT FROM AUTHOR]

KM clustering is the most popular technique that finds each cluster's hidden intrinsic pattern in a given real-life application dataset. But it has some limitations, like its run time complexity is very high for high dimensional data sets, and this clustering is very sensitive to its initial centroids. This traditional approach requires the number of clusters, k, in advance for KM, which will not give good quality of clusters, and at the time, this algorithm converges to local optimal solution. So, for solving the problem of local optimal solutions, this paper presented some of the updated NI meta-heuristic algorithms, which has been hybridized with the KM clustering. This hybridized algorithm converges to global optimal solutions rather than local optima in a large search space. Further, we discussed some python API packages from scikit-learn.org for hybrid KM clustering that gives good quality of clusters, and at last, we describe some comparative analyses of KM clustering with integrated KM (KM+NIC). Most of the integrated KM show better accuracy results compared to traditional KM clustering. [ABSTRACT FROM AUTHOR]

This paper concerns to the RCPS problem with imprecise activity duration times and flexible constraints Schedule input data and constraints are modeled by fuzzy numbers. Fuzzy RCPS problem is based on the concept of pair-wise dominance between two fuzzy numbers and solved with the use of simulation. [ABSTRACT FROM AUTHOR]

The design of course timetables for academic institutions is a very difficult job due to the huge number of possible feasible timetables with respect to the problem size. This process contains lots of constraints that must be taken into account and a large search space to be explored, even if the size of the problem input is not significantly large. Different heuristic approaches have been proposed in the literature in order to solve this kind of problem. One of the efficient solution methods for this problem is tabu search. Different neighborhood structures based on different types of move have been defined in studies using tabu search. In this paper, different neighborhood structures on the operation of tabu search are examined. The performance of different neighborhood structures is tested over eleven benchmark datasets. The obtained results of every neighborhood structures are compared with each other. Results obtained showed the disparity between each neighborhood structures and another in terms of penalty cost. [ABSTRACT FROM AUTHOR]