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Swarm intelligence (SI) is an artificial intelligence technique based on the study of cooperation behaviors of simple individuals (e.g., ant colonies, bird flocking, animal herding, and bees gathering honey) in various decentralized systems. The population, which consists of simple individuals, can usually solve complex tasks in nature by individuals interacting locally with one another and with their environments. Although a simple individual’s behavior is primarily characterized by autonomy, distributed functioning, and self-organizing capacities, local interactions among the individuals often lead to a global optimal solution. Therefore, swarm intelligence is a promising way to develop powerful solution methods for optimization problems in engineering.

However, for large and complex engineering problems, SI algorithms often consume too much computation time due to the stochastic features of their searching approaches. For this reason, there is a potential requirement to develop efficient algorithms that are able to find solutions under limited resources, time, and money in real-world applications.

This special issue is aimed at highlighting the most significant recent developments on the topics of SI and to apply SI algorithms in real-life scenarios. Papers selected for this special issue present new findings and insights into this field. A broad range of topics are discussed, especially in the following areas: benchmarking and evaluation of new SI algorithms, convergence proof for SI algorithms, comparative theoretical and empirical studies on SI algorithms, and SI algorithms for real-world application.

Some works focus on the application of SI in the area of traffic and transportation. For example, in the paper entitled “

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Also, the SI is discussed in the area of computer science. In the paper entitled “

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There are also some works focusing on the application of SI in the operation research and management science. In the paper entitled “

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Besides those mentioned above, some authors present the application of SI in the electrical and electronic engineering. In the paper entitled “

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There are several papers that apply SI in the civil engineering. In the paper entitled “

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Communication is another realm where SI can be applied. In the paper entitled “

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There are also two papers discussing the SI in automotive engineering. In the paper entitled “

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Some works use the SI in robotics. In the paper entitled “

The robot path planning problem is also attempted by J. J. Liang et al. In their paper entitled “

The following four papers mainly focus on enhancing the representative SI algorithms. In the paper entitled “

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These articles present rich and valuable advancements that SI technologies have made for solving problems in engineering. We would like to thank all the authors for their excellent work and contributions to this special issue. We would also like to express our gratitude to all the reviewers for their fundamental work and patience in assisting us.