Coastal resilience has received significant attention for managing beach erosion issues. We introduced flexible artificial coral reef (ACR) structures to diminish coastal erosion, but planar installation effects should be considered to evaluate the feasibility of coastline maintenance. In this study, we conducted a three-dimensional large-scale experiment to investigate the characteristics of planar installation of ACR, focusing on the wave mitigation performance, wave profile deformation with delay, nearshore current movement, deposition and erosion trends, and beach profile variation. We found that the ACR diminished the wave height by ~50% and the current intensity by ~60% compared with that of a conventional submerged breakwater made of dolos units. Using the dispersion velocity of the dye in a tracer experiment, the dispersion time of the ACR was approximately 1.67-times longer than that of the dolos and the current velocity was reduced, revealing that ACR significantly reduced structural erosion. With dolos, severe erosion of >10 cm occurred behind the structure, whereas there was only slight erosion with the ACR. Moreover, in a vertical beach-profile analysis, the ACR exhibited greater shoreline accretion than that of dolos. These results indicate the potential of ACR in improving coastal resilience.

Urban micro-tidal canals frequently suffer from severe hypoxia due to restricted hydrodynamic exchange and untreated discharges. Field monitoring during a 2022 mass fish mortality event at the Dongsam tidal canal revealed that during the ‘tidal window gap’—a hydraulic stagnation period required for passive tidal flushing—bottom-layer dissolved oxygen plummeted to a critical anoxic state (0.44 mg/L). To overcome passive tidal exchange limitations, this study proposes a hybrid water purification framework integrating active ecological interventions: wall-mounted spiral flow aeration for continuous oxygenation and vertical bio-curtains for pollutant interception. Synergizing fluid mechanics with ecological engineering, core design parameters were systematically derived: effective mixing width (W_eff≈2.5h), longitudinal spacing (L_s = 10 × W_eff), optimal root immersion ratio (D_r/h = 0.6), and climate-adaptive planting densities (ρ_p≈12–32 plants/m²). Additionally, a corrosion-resistant FRP guide rail system was incorporated to facilitate autonomous adaptation to tidal fluctuations. The framework was conceptualized through a prototype design for the Dongsam canal and subsequently scaled to 15 international micro-tidal canals across diverse climatic zones. Ultimately, this research presents a comprehensive methodological framework and a flexible engineering toolkit intended to guide future water quality and ecological resilience enhancements in shallow urban waterways worldwide.

Urban micro-tidal canals frequently suffer from severe hypoxia due to restricted hydrodynamic exchange and untreated discharges. Field monitoring during a 2022 mass fish mortality event at the Dongsam tidal canal revealed that during the ‘tidal window gap’—a hydraulic stagnation period required for passive tidal flushing—bottom-layer dissolved oxygen (DO) plummeted to a lethal 0.44 mg/L. To address the limitations of passive tidal exchange, this study proposes a conceptual hybrid water purification framework integrating active ecological interventions: wall-mounted spiral flow aeration for continuous oxygenation and vertical bio-curtains for pollutant interception. By synergizing fluid mechanics with ecological engineering, core design parameters were systematically derived: an effective mixing width ($W_{eff}=2.2 h$), longitudinal spacing ($L_s$ = 13.6$\times W_{eff}$), an optimal root immersion ratio ($D_r/h$ = 0.6), and climate-adaptive planting densities (${\rho }_p\approx$12–32 plants/m²). Additionally, a corrosion-resistant FRP guide rail system was incorporated to facilitate autonomous adaptation to tidal fluctuations. The framework was conceptualized through a prototype design for the Dongsam canal and subsequently scaled to 15 international micro-tidal canals across diverse climatic zones. The optimized bilateral staggered configuration established a continuous 528 m² ecological refuge, ensuring DO levels recover above the critical 3 mg/L threshold. Ultimately, this research presents a comprehensive methodological framework and a flexible engineering toolkit to guide water quality and ecological resilience enhancements in shallow urban waterways worldwide.

As regional industrial hubs face structural decline, the "Regional industrial resurrection (RIR)" model—utilizing Open Labs to integrate high-end infrastructure with customized corporate support—emerges as a critical solution to bridge the systemic "triple burden" of capital, talent, and infrastructure deficits. This study evaluates the Busan maritime Open Lab's performance (2021–2022) focusing on representative SMEs, with outcomes strictly verified by national authorities. Technical KPIs improved significantly: design lead times were reduced by 50–60%, and technology readiness advanced from TRL 5 to 9. High-fidelity results included 0.027% spatial precision and 91 FPS rendering stability, facilitating industrial-grade digital twin commercialization. Economically, these firms realized over 3.3 million USD in consolidated revenue, achieving a +66.4% organic growth rate based on a constant exchange rate to isolate macroeconomic volatility. Socially, the Open Lab’s contribution resulted in 11.5 verified new employees, proving the model’s capacity for regional job creation. Qualitative surveys revealed a 100% satisfaction rate for technical advisory, confirming the Open Lab’s role as an essential "Innovation intermediary". Finally, the study proposes tailored expansion strategies for Taebaek/Samcheok, Gumi, and Gunsan across South Korea. These findings underscore the vital importance of public-led shared infrastructure and specialized human capital support in responding to declining regional industries.