• Journal of Navigation and Port Research
• /
• v.46 no.3
• /
• pp.243-250
• /
• 2022

The purpose of this study was to propose technology to detect the wave in the image in real-time, and calculate the height of the wave-overtopping through image analysis using artificial intelligence. It was confirmed that the proposed wave overtopping detection system proposed in this study could detect the occurring of wave overtopping, even in severe weather and at night in real-time. In particular, a filtering algorithm for determining if the wave overtopping event was used, to improve the accuracy of detecting the occurrence of wave overtopping, based on a convolutional neural networks to catch the wave overtopping in CCTV images in real-time. As a result, the accuracy of the wave overtopping detection through AP50 was reviewed as 59.6%, and the speed of the overtaking detection model was 70fps based on GPU, confirming that accuracy and speed are suitable for real-time wave overtopping detection.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.7 no.4
• /
• pp.604-611
• /
• 2003

Currently, Busan Metropolitan City is under the economic depression. To solve these problems, this study attempts to provide strategies for building local IT policies, especially for vitalizing software industry. Firstly, it analyzes the trends and basic status on the Busan software industry. Secondly, case studies by S/W policy initiators are conducted, and followed by empirical studies including in-depth interviews from government officials, researchers, and businessmen in Busan metropolitan city. Finally, it provides policy alternatives and strategies for building the local S/W development policies including the role and necessity of S/W industry in vitalizing the local economy, improving financial capacity of local governments, reorganizing of relationship among different levels of governments, and the possibility of integration of policy instruments and organizations.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2001.10a
• /
• pp.183-186
• /
• 2001

For a long time, the ocean was regarded as unknown area ruled by god, consequently, not so much things were developed in scientific methods and activities. Despite a rapid development of geographic information systems(GIS) marine and ocean fields still remained in the scope of traditional tools and intuitive experiences by the late of 1990. However, land based concepts and technology models require additional customization to apply GIS effectively in marine domains, which are resulted from her dynamic, complex and seamless massive nature. This paper gives a brief review of marine spatial data characteristics and also presents strategic approaches to meet the unique marine GIS requirements.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2015.05a
• /
• pp.194-200
• /
• 2015

본 연구에서는 하천부터 하구까지의 댐 구조물 건설로 인해 해안으로의 표사 공급원이 감소하는 것을 정량적으로 검토하였다. 내륙과 해양의 전이역인 연안은 농수산업, 임해산업단지, 발전소 및 항만과 같은 산업 인프라, 관광 및 레크리에이션 등의 다양한 편익을 제공하여 높은 경제 사회 환경적 가치가 있다. 그러나 80년대 이후 무분별하게 추진되어온 각종 연안 개발은 직 간접적인 해안의 침식문제를 발생시켰다. 우리나라 서해의 경우 하천으로부터의 토사 유입 차단은 심각한 수준이다. 아직 그 영향이 해안으로 완전히 파급되지 못하여 그로 인한 장기 해안 침식이 두드러지지 않고 있으나 고파랑에 의한 빈번한 침식과 저질의 세립화 현상을 통하여 현재 진행형임을 알 수 있다. 그러나 일단 피해가 심각해지기 시작하면 돌이킬 수 없는 재앙이 될 측면도 많다. 따라서 우리나라 유역의 개발과 수리구조물 건설 현황을 살펴 이로 인한 해안 침식 결과가 얼마나 심각할 수 있는 지를 살펴본다. 본 연구에서는 수리구조물로 인한 토사량 감소 중 가장 주요한 토사 공급원 감소 원인인 댐으로 인한 토사량 감소율에 대한 연구를 진행한다. 먼저 각 댐의 건설 전, 유역면적당 토사량과 댐 건설 후, 해안 유입 토사량 사이에 감소율을 계산하고, cascade 방법에 의하여 댐군에 의한 토사감소율을 산정한다. 유입 토사량 감소율을 산정하고 토사 공급원 감소로 인한 표사 수지 분석을 통해 해안 침식 폭의 위험도 평가를 실시한다.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.27 no.2
• /
• pp.83-90
• /
• 2023

The recent increase in earthquake activities has highlighted the importance of seismic performance evaluation for civil infrastructures. In particular, the container crane essential to maintaining the national logistics system with port operation requires an exact evaluation of its seismic response. Thus, this study aims to assess the seismic vulnerability of container cranes considering their seismic characteristics. The seismic response of the container crane should account for the structural members' yielding and buckling, as well as the crane wheel's uplifting derailment in operation. The crane's yielding and buckling limit states were defined using the stress of crane members based on the load and displacement curve obtained from nonlinear static analysis. The derailment limit state was based on the height of the rail, and nonlinear dynamic analysis was performed to obtain the seismic fragility curves considering defined limit states and seismic characteristics. The yield and derailment probabilities of the crane in the near-fault ground motion were approximately 1.5 to 4.7 and 2.8 to 6.8 times higher, respectively, than those in the far-fault ground motion.

• Journal of Navigation and Port Research
• /
• v.45 no.6
• /
• pp.333-345
• /
• 2021

Amid the rapidly changing logistics environment and demand changes in the post-corona-19 era, the importance of the cold chain logistics sector is being highlighted. The scope of cold chain is not limited to food, but is expanding to various fields such as pharmaceuticals, semiconductors, and flowers. The demand on the storage and transportation of corona vaccines is rapidly increasing. The rapid increase in domestic low-temperature facility construction and renovation may lead to the saturation of the cold chain related industry in the future and slow growth. In preparation for this, it is necessary to accumulate infrastructure know-how using IT technologies, and to consider entering into the UN procurement market as a potential niche market, by taking advantage of Korea's recent global status. The demand for cold chain in the UN procurement market is increasing mainly in underdeveloped countries, and it is expected to continue to grow. In this paper, the capabilities of domestic cold chain related companies were analyzed, domestic and overseas cold chain logistics market trends and overseas market entry status were investigated. An in-depth survey was conducted to present strategies for domestic cold chain logistics related companies to enter the UN procurement market.

• Journal of the Korean Geotechnical Society
• /
• v.38 no.12
• /
• pp.91-101
• /
• 2022

The 1995 Kobe earthquake caused a massive damage to the Port of Kobe. Therefore, it was pointed out that it was impossible to design port structures for Level II (Mw 6.5) earthquakes with quasi-static analysis and Allowable Stress Design methods. In Japan and the United States, where earthquakes are frequent, the most advanced design standards for port facilities are introduced and applied, and the existing seismic design standards have been converted to performance-based design. Since 1999, the Korean Port Seismic Design Act has established a definition of necessary facilities and seismic grades through research on facilities that require seismic design and their seismic grades. It has also established a performance-based seismic design method based on experimental verification. In the performance-based seismic design method of the breakwater proposed in this study, the acceleration time history on the surface of the original ground was subjected to a fast Fourier transform, followed by a filter processing that corrected the frequency characteristics corresponding to the maximum allowable displacement with respect to performance level of the breakwater and the filtered spectrum. The horizontal seismic coefficient for the equivalent static analysis considering the displacement was calculated by inversely transforming (i.e., subjected to an inverse fast Fourier transform) into the acceleration time history and obtaining the maximum acceleration value. In addition, experiments and numerical analysis were performed to verify the performance-based seismic design method of breakwaters suitable for domestic earthquake levels.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.29 no.5
• /
• pp.445-455
• /
• 2023

Sea level rise due to global warming is accelerating. According to the IPCC survey, the expected sea level rise in 2100 was analyzed to be 47cm in the low-carbon scenario (SSP 1-2.6) and 82cm in the high-carbon scenario (SSP 5-8.5). Sea level rise can cause serious damage to port infrastructure and reduce the safety of ships docked inside ports. In this study, Mokpo Port, which frequently suffers from flooding during high tide, was selected and the sensitivity of mooring evaluation factors was analyzed for actual berthing ships according to sea level rise scenarios. From the analysis, we found that the tension of mooring line, the load of bollard, vertical angle of mooring line, and ship's motion of 6-DOF, which are evaluation factors, generally increased when the sea level increased. The most sensitive evaluation factor was sway motion of 6-DOF. Also, we analyzed that the value of mooring evaluation factors decreased when the crown height was raised. This was beneficial in improving ship and pier safety. The results of this study can be used as basic data to secure measures to improve port and ship safety according to sea level rise in Mokpo Port.

• Journal of Navigation and Port Research
• /
• v.47 no.6
• /
• pp.430-436
• /
• 2023

Study on Changes in Vessel Traffic Services Due to Introduction of Maritime Autonomous Surface ShipsThe development of technologies related to Maritime Autonomous Surface Ships (MASS) has been actively progressing since the mid-2010s, focusing on themes such as collision avoidance, route planning, digital twin, and communication technologies. On the other hand, research on land-based infrastructure connected with MASS, such as logistics systems, port facilities, and vessel traffic services, has relatively received less attention. This study analyzed impact of emergence of MASS on existing vessel traffic service operations and proposed changes in control operations to prepare for its impact. To do this, current vessel traffic service operations were analyzed and elements of MASS technology that could affect vessel traffic control were identified. A survey was conducted among vessel traffic controllers to identify items related to the control of MASS. Results analyzed using the AHP method showed that preparation for emergency response and communication methods with MASS were the most important. Based on this, we were able to derive detailed plans for basic MASS control procedures and emergency response procedures based on data communication within maritime traffic control areas. MASS control procedures proposed in this study are expected to be used as a solution to resolve issues related to traffic safety of MASS in coastal areas.

• Korean Journal of Remote Sensing
• /
• v.40 no.1
• /
• pp.19-31
• /
• 2024

Ports are vital social infrastructures that significantly influence both people's lives and a country's economy. In South Korea, the aging of port infrastructure combined with the increased frequency of various natural disasters underscores the necessity of displacement monitoring for safety management of the port. In this study, the time-series displacements of Yeongilman Port and surrounding areas in Pohang, South Korea, were measured by applying Permanent Scatterer Interferometric Synthetic Aperture Radar (PSInSAR) to Sentinel-1 SAR images collected from the satellite's ascending (February 2017-July 2023) and descending (February 2017-December 2021) nodes, and the displacement associated with the 2017 Pohang earthquake in the port was analyzed. The southern (except the southernmost) and central parts of Yeongilman Port showed large displacements attributed to construction activities for about 10 months at the beginning of the observation period, and the coseismic displacement caused by the Pohang earthquake was up to 1.6 cm of the westward horizontal motion and 0.5 cm of subsidence. However, little coseismic displacement was observed in the southernmost part of the port, where reclamation was completed last, and in the northern part of the oldest port. This represents that the weaker the consolidation of the reclaimed soil in the port, the more vulnerable it is to earthquakes, and that if the soil is very weakly consolidated due to ongoing reclamation, it would not be significantly affected by earthquakes. Summer subsidence and winter uplift of about 1 cm have been repeatedly observed every year in the entire area of Yeongilman Port, which is attributed to volume changes in the reclaimed soil due to temperature changes. The ground of the 1st and 2nd General Industrial Complexes adjacent to Yeongilman Port subsided during the observation period, and the rate of subsidence was faster in the 1st Industrial Complex. The 1st Industrial Complex was observed to have a westward horizontal displacement of 3 mm and a subsidence of 6 mm as the coseismic displacement of the Pohang earthquake, while the 2nd Industrial Complex was analyzed to have been little affected by the earthquake. The results of this study allowed us to identify the time-series displacement characteristics of Yeongilman Port and understand the impact of earthquakes on the stability of a port built by coastal reclamation.