The genetic algorithm (GA) is an effective method to solve the path-planning problem and help realize the autonomous navigation for and control of unmanned surface vehicles. In order to overcome the inherent shortcomings of conventional GA such as population premature and slow convergence speed, this paper proposes the strategy of increasing the number of offsprings by using the multi-domain inversion. Meanwhile, a second fitness evaluation was conducted to eliminate undesirable offsprings and reserve the most advantageous individuals. The improvement could help enhance the capability of local search effectively and increase the probability of generating excellent individuals. Monte-Carlo simulations for five examples from the library for the travelling salesman problem were first conducted to assess the effectiveness of algorithms. Furthermore, the improved algorithms were applied to the navigation, guidance, and control system of an unmanned surface vehicle in a real maritime environment. Comparative study reveals that the algorithm with multi-domain inversion is superior with a desirable balance between the path length and time-cost, and has a shorter optimal path, a faster convergence speed, and better robustness than the others.

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The Japan Sea Rim (JSR) region is the core area for the future sustainable development of Northeast Asia. Effectively assessing the impact of urban expansion on grain production is of great significance for achieving sustainable development goals (SDGs), such as SDG2 Zero Hunger, and promoting sustainable development in Northeast Asia. Only a few studies have assessed the impact of urban expansion on grain production in the JSR. In this study, we initially analyzed urban expansion in the JSR for the period 1992 to 2050. Then, we assessed the impact of urban expansion on cropland net primary productivity (NPP) based on NPP data. Finally, we evaluated the impact of urban expansion on grain production in the JSR. The results indicated that urban land expanded from 21,509 km2 to 42,501 km2 in the JSR between 1992 and 2020 (an increase of 1.98 times), and the occupation of cropland caused by urban expansion resulted in a decrease of 2.21 million t in grain production. Urban land will continue to expand from 2020 to 2050, which will cause grain production to decrease by 1.68 (1.02–2.24) million t. China will experience the most serious loss of grain production, accounting for 62.93% (56.69–71.60%) of the total grain production loss in the JSR. Considering the situation for the period 1992–2020, the impact of urban expansion on grain production will be moderated in the future. Thus, the future grain production loss will be reduced by 24.18% (8.80–53.98%). However, future urban expansion will continue to have a negative impact on regional food security. Therefore, we suggest that urban development should be reasonably regulated and high-quality cropland should be protected. Meanwhile, we should strengthen international cooperation and optimize food and economic trade among different countries in the JSR to ensure food security and promote sustainable regional development.