The objective of this study was to assess the effects of gypsum application on dry matter yield (DMY), mineral content of alfalfa (Medicago sativa L.), and soil properties in reclaimed tidal land in South Korea. The experiment was conducted in Seokmun, located on the west coast of South Korea, which is reclaimed with approximately 70 cm depth of degraded island soil. Treatments consisted of a control with no gypsum application (G0), 2 ton ha-1 (G2), and 4 ton ha-1 (G4) of gypsum application. The first harvest was carried out when the alfalfa reached 10% flowering, and subsequent harvests were conducted at 35-day intervals. Over the three-year experimental periods (2019-2021), the total DMY of G2 treatment was significantly higher than those of G0 and G4 (p<0.05). Although both G2 and G4 gypsum application treatments lowered soil pH, the G4 treatment increased the electrical conductivity (EC) content of the soil. Additionally, gypsum application affected the mineral contents of alfalfa, resulting in reduced concentration of sodium (Na) and Magnesium (Mg). Therefore, this present study suggests that a gypsum application rate of 2 ton ha-1 is optimal for improving alfalfa dry matter yield and mineral balance, as well as enhancing soil chemical properties in reclaimed tidal land in South Korea.

This study aims to identify and prioritize the key factors essential for transforming a traditional port into a smart port using the Fuzzy Analytic Hierarchy Process (Fuzzy AHP) based on Chang’s extent analysis method. Based on the insights of 30 experts from Vietnam and South Korea, the research framework comprises three main dimensions, namely Policy, Operation, and Environment, which are further divided into ten sub-factors. The analysis revealed that Policy and Operation were perceived as the most critical dimensions, while Environment received relatively less emphasis. At the factor level, Automation & Intelligent Infrastructure ranked highest, followed by Investment & Financial Support, Productivity, and Regulatory Frameworks. In contrast, environmental factors such as Water & Waste Management and Emission Control were ranked lowest. Notably, Vietnamese and Korean experts all value the importance of advanced technology and investment capacity but still have some differences in prioritizing the other factors, reflecting differing national contexts and developmental stages. These findings offer strategic guidance for policymakers and port authorities in tailoring smart port development strategies to local conditions and priorities.

Virtual Reality Head Mounted Display (VR HMD)-based flight simulators have recently emerged as promising tools for enhancing pilot training effectiveness. This study aims to establish a set of evaluation criteria for the development of VR HMD-based flight simulators and to determine their relative importance and priority using the Analytic Hierarchy Process (AHP). Through an extensive review of the literature, a hierarchical evaluation model was constructed, consisting of three primary criteria and ten sub-criteria. A structured questionnaire was administered to experienced pilots, and the collected data were analyzed using the AHP methodology to assess the relative weights of each criterion. The analysis revealed that the fidelity of system performance is the most influential factor in evaluating VR HMD-based flight simulators. These findings present a structured evaluation framework and offer practical insights for guiding the strategic development and optimization of VR HMD-based flight training systems.