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A rapid and efficient system to adapt commercially available polymers for melt electrowriting (MEW) for the fabrication of micro‐fibrous scaffolds is introduced. Poly(ε‐caprolactone) (PCL) is currently the gold standard for MEW due to its low melt viscosity and its use in tissue regeneration. While several other polymers have been used for MEW, they involve small‐scale custom synthesis meaning beyond PCL there is a scarcity of commercial polymers suitable for MEW. Furthermore, PCL has a long degradation time and lacks the elasticity needed for many applications. Poly(L‐lactide‐co‐ε‐caprolactone) (PLCL) is an elastic polymer with relatively fast degradation profile and is commercially available in high purity. Its high melt viscosity, however, makes it incompatible with MEW at normal operating temperatures. Rather than modifying the MEW machine, this study uses a simple pre‐treatment of PLCL to tailor the melt viscosity. This treatment involves heating PLCL at 150 °C for 24–48 h to enable MEW printing into scaffolds at 110 °C with fiber diameters 14–40 µm. Scaffolds maintained their elasticity after the thermal degradation process, becoming the first PLCL low‐temperature MEW scaffolds. Moreover, this approach can be readily adapted by any MEW user without manipulating the polymer beyond the thermal treatment in an oven. [ABSTRACT FROM AUTHOR]

Kim, D.S.; Kim, D.-H.; Park, J.-R.; Lee, S.-Y., and Kim, H.-Y., 2023. Analysis of tsunami characteristics along Korea's southern coast using a hypothetical scenario. In: Lee, J.L.; Lee, H.; Min, B.I.; Chang, J.-I.; Cho, G.T.; Yoon, J.-S., and Lee, J. (eds.), Multidisciplinary Approaches to Coastal and Marine Management. Journal of Coastal Research, Special Issue No. 116, pp. 343-347. Charlotte (North Carolina), ISSN 0749-0208. Large-scale earthquakes are occurring globally, especially in the South Asian crust, which is experiencing a state of tension in the aftermath of the 2011 East Japan Earthquake. Uncertainty and fear regarding the possibility of further seismic activity in the near future have been on the rise in the region. The National Disaster Management Research Institute has previously studied and analyzed the overflow characteristics of a tsunami and the rate of flood forecasting through tsunami numerical simulations of the East Sea of South Korea. However, there is currently a significant lack of research on the Southern Coast tsunamis compared to the East Coast. On the Southern Coast, the tidal difference is between 1-4 m, and the impact of the tides is hard to ignore. Therefore, it is necessary to analyze the impact of the tide propagation characteristics on the tsunami. Occurrence regions that may cradle tsunamis that affect the southern coast region are the Ryuku Island and Nankaitlov Fault Zone, which are active seafloor fault zones. The Southern Coast has not experienced direct damage from tsunamis before, but since the possibility is always present, further research is required to prepare precautionary measures in the face of a potential event. Therefore, this study numerically simulated a hypothetical tsunami scenario that could impact the southern coast of South Korea. In addition, the tidal wave propagation characteristics that emerge at the shore due to tide and tsunami interactions will be analyzed. This study will be used to prepare for tsunamis that might occur on the southern coast through tsunami hazard and risk analysis. [ABSTRACT FROM AUTHOR]

Lee, S.Y.; Jeong, Y.H.; Park J.Y., and Hur, D.S., 2023. Tsunami waveform characteristics of the Korean Peninsula. In: Lee, J.L.; Lee, H.; Min, B.I.; Chang, J.-I.; Cho, G.T.; Yoon, J.-S., and Lee, J. (eds.), Multidisciplinary Approaches to Coastal and Marine Management. Journal of Coastal Research, Special Issue No. 116, pp. 71-75. Charlotte (North Carolina), ISSN 0749-0208. Solitary waves, primarily used to analyze hydraulic phenomena in tsunamis, have a significantly narrower waveform than tsunamis. In this study, numerical analysis using ADCIRC was conducted to scrutinize tsunami waveform characteristics that have previously affected the Korean Peninsula. The results showed that waveforms in the Sea of Japan tsunami (1983) and the Okushiri tsunami (1993) were 6.97–17.49 times larger than theoretical solitary waves and, on average, were 11.17 times more widely distributed. Findings show that hydraulic characteristics are highly likely to be underestimated if solitary waves are to replace tsunamis in the design of coastal and port structures. [ABSTRACT FROM AUTHOR]

Lee, W.-D.; Lee, S.-Y.; Park, J.-R., and Hwang, T., 2023. Collision characteristics according to contact conditions between drifting objects and fixed structures in the coastal zone. In: Lee, J.L.; Lee, H.; Min, B.I.; Chang, J.-I.; Cho, G.T.; Yoon, J.-S., and Lee, J. (eds.), Multidisciplinary Approaches to Coastal and Marine Management. Journal of Coastal Research, Special Issue No. 116, pp. 21-25. Charlotte (North Carolina), ISSN 0749-0208. When an object drifting due to a tsunami collides with a structure, the collision force varies significantly depending on the magnitude of the earthquake or tsunami, the weight of the drifting object, the collision velocity, and the distance between the drifting object and the structure. In general, the collision force is proportional to the collision velocity and the weight of the drifting object but also dependent on the contact cross-section between the two objects. In this study, LS-DYNA, a computer simulation program specialized in dynamic analysis, was used to analyze the collision characteristics between a drifting object and a structure, focusing on the contact cross-section between the two objects. In this collision analysis, a 20-foot container was used as the drifting object, while a leg of a port crane was used as the fixed structure. The analysis results suggested that a face-to-face collision between the two objects resulted in a collision force up to 89% greater than an edge-to-face collision between the rotated container and the fixed leg of the crane. This study confirmed that the contact cross-section, along with the weight and collision velocity of the drifting object, significantly impact the collision behavior caused by drifting objects due to tsunamis. [ABSTRACT FROM AUTHOR]