 This study developed an artificial neural network, ANN, cellular automata, CA, model called OICL-ANNCA to address limitations in land use simulations of coastal cities, specifically in simulating new urban land outside the research boundary. The model exhibited better simulation accuracy and effectively simulated new urban land expansion, providing a reference for delimiting the UDB and defining the research boundary for fast-growing coastal cities in China. This article was authored by Fei He, Jun Yang, Yucheng Zhong, and others.