• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1991.06a
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• pp.37-44
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• 1991

영산강 하구언 방조제의 건설로 인한 항만 및 이의 인접해역 해면의 변화는 예상한 바 있으며 실제 여러개소에서 월 2회정도의 주기로 목포 구항부근 상업지역에서 해면상승에 따라 주기적으로 침수되는 현상이 나타나고 있다 목포항의 영산강 하구언 방조제 조성으로 인한 조류성분중 최고기록을 가진 수로에서는 6kts 정도로 감소된 것으로 보고되고 있으나 주위자연환경 변화에 따른 수면 상승 및 해수면의 주기적인 변화 등에 대한 상세한 언급 및 깊이 있는 분석은 회피되어왔다. 수자원의 효율적관리를 위해 하구언 방조제는 이미 건설되었고 앞으로 대규모의 항만개발과 대불산업단지조성을 위해 추가 3개의 만입해안해역에 댐으로 해역을 막아 매립공사를 추진하고 있다 그러나 이 지역에 대한 분석은 타당성의 여부만을 강조한 상업적 용역이 이루어지고 있고 장래 개발에 대해 학술적이고 실질적인 문제점 추출과 해결방아네 대해서는 무시하거나 경시한 바가 많다 더구나 태풍 저기압 등과 같은 자연재해를 고려한 분석은 시도되지 못하고 있다 따라서 개발전후의 현상에 대한 상세한 자료 및 현장 조사와 극한 상태를 고려하여 개발에 따른 수위상승 부진동, 조류 수질등 이해역의 변화요소를 수집하고 분석하며 과학적 접근방법에 기초를 둔 수치모델의 실험을 포함하여 현장관측 및 측정자료를 검증하는 것이 필수적이라고 사료되어 종합분석의 한단계로 여기서는 하구언 및 하구간척(Land Reclamatic of Estuary barren)으로 해역축소에 따른 해면변화의 실제현상을 조사하여 정리하고 이를 수치모델을 통해 시뮬레이션하여 보았다 이는 종합개발의 좋은 기초자료로 이용됨은 물론이로 이지역의 개발에 기여할 것으로본다.적절하게 가정된 지반의 응력-변형률 관계와 간극수압특성에 의하여 고려되었다. 그 결과 응력 및 변위가 심하게 발생하는 지역은 황색 점토층이었으며 이로부터 황색 점토층에서 부터 파괴면이 생성되어 다른 지역으로 전파되었음을 유추할 수 있었다.form trap with 2.88[eV] deep of injected space charge from the chathode in the crystaline regions. The origin of ${\alpha}$$_2$ peak was regarded as the detrapping process of ions trapped with 0.9[eV] deep originated from impurity-ion remained in the specimen during production process of the material, in the crystalline regions. The origin of ${\beta}$ peak was concluded to be due to the depolarization process of "C=0"dipole with the activation energy of 0.75[eV] in the amorphous regions. The origin of ${\gamma}$ peak was responsible to the process combined with the depolarization of "CH$_3$", chain segment, with the activation energy of ca

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.5
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• pp.228-238
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• 2017

In coastal region, tidal harmonic constants of semi-diurnal tides and nonlinear tides were collected. The observed tide data of KHOA were analyzed by a tide harmonic analysis method. In the southwestern coasts and Han river estuary, nonlinear tides are clearly generated. The generation of tide non-linearity and tide asymmetry is closely related with tide form factor in Korean coastal zone. Tide non-linearity and asymmetry in Mokpo harbour have increased by a series of coastal development projects. The increase has caused rise of high water level and drop of low water level, and increase of tidal range. In Kunsan Outport, tidal range has been declined due to inter-annual change of nonlinear tides after completion of Samangeum sea-dyke.

• Journal of the Korean Society of Marine Environment & Safety
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• v.10 no.1 s.20
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• pp.15-22
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• 2004

The navigation area approach to Mokpo port consists of narrow channels with 30mile section, and the route is crossed with many fairways. In particular, fairway routeing except Mokpogu is not assigned and there are many threatening factors against the safe operation of vessel because fishing and mining areas are designated. Therefore, this paper proposed elements for safe passage through a marine traffic environmental assessment with the analysis of surrounding environment, dangerous elements, traffic survey and marine casualty.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.1
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• pp.74-80
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• 2021

When a berth is built close to a fairway, a moored vessel will be affected by the ship waves generated by navigating vessels. In this study, a portable measurement system was developed to measure the roll motion of an actual vessel, and the results were compared with simulation results. The simulation results showed that the roll motion satisfies the loading safety criteria. However, the actual results of the vessel, did not satisfy the criteria in some cases. In this study, 18 cases that did not satisfy the loading safety criteria were analyzed. Among these cases, three cases were affected by a different time zone of the remaining 15 cases, 11 cases (73.3%) were observed to be consistent with arrival times of passenger ships of more than 10,000GT sailing between in Mokpo and Jeju. The results of this study can be used to reflect marine traffic characteristics in the assessment of loading safety, which can increase the reliability of results of the loading safety assessment of ships.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.5
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• pp.476-482
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• 2013

This study aims to enhance the effectivity of VTS(Vessel Traffic Service) control by investigating the minimum safe distance between vessel and vessel, vessel and land(obstacle) for the vessel's safe navigation within the VTS control area. In addition, to suggest basic data for the safe navigation, this study has done survey and analysis to each VTS center, and individual on the minimum safe distance to VTS operators of each ports of korea. Through ocean voyage by training ship, Singapore and Malacca strait's congested vessel traffic zone's control distance was compared and investigated the difference on safe distance by the different VTS operators. As a result, there was huge difference of minimum safe distance between the VTS operators belong to the same center. Over all, the port with gentle coastline, like donghae, the safe distance was wider than the other port. On the other hand, port with complex coastline and frequent entry and departure of the vessel, like mokpo, the safe distance was the shortest of all. Therefore, development of module suitable to port's natural conditions and traffic volume's necessity is required, for the operators affiliated to the same VTS center control according to formal method. Lastly, the full discussion by the expert group about establishment of standard control procedure in the future should be considered as well.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.11a
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• pp.17-18
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• 2019

해상교통관제 업무의 최적화를 위하여 요구되는 인적요소 분야 중 관제사의 상황인식(SA: Situation Awareness)와 관제 업무부하(Workload)와의 관계성을 확인하는 것이 해상교통 분야에서는 중요한 실정이다. 이 연구에서는 관제사의 상황인식과 업무부하를 상황인식평가기술(SART)과 다차원 작업부하 지표(NASA-TLX)를 실제적으로 측정하고, 측정 결과를 비교함으로서 개념들에 대한 이해와 시스템적으로 관리할 수 있는 방법을 제시함으로써 해상교통관제사 전문성 제고방안에 기여하고자 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.05a
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• pp.38-39
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• 2019

Optimal route planning is the route planning to minimize voyage time or fuel consumption in a given ocean environment. Unlike the previous studies on weather routing, this study proposes an optimization method for the route planning to avoid the grounding risk in the coast. The route way-points were searched using Dijkstra algorithm, and then the optimization was performed to minimize fuel consumption by setting the optimization design parameter to the engine rpm. To set the engine rpm, a method to use the fixed rpm from the departure point to the destination point, and a method to use the rpm for each section by dividing the route were used. The ocean environmental factors considered for route planning were wind, wave, and current, and the depth information was utilized to compute grounding risk. The proposed method was applied to the ship passing between Mokpo and Jeju, and then it was confirmed that fuel consumption was reduced by comparing the optimum route and the past navigated route.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.341-342
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• 2018

Unlike previous studies on the optimum route of the ship operating on th ocean, this study proposed an optimization method for the route planning of the ship operating on the coast. In general, passenger ships on the coast navigate along the waypoints indicated in the authorized route. Therefore this study propose objective function considering the braking power and time to determine the speed between waypoints, and the optimum speed was determined by applying the proposed method to the actual route of the passenger ship between Mokpo and Jeju.

• Journal of Navigation and Port Research
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• v.42 no.6
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• pp.453-458
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• 2018

The analysis of maritime traffic refers to the processes that are used to analyze the environmental characteristics of the target area and, based on this analysis, predict the traffic pattern of the vessels. In recent years, maritime traffic analysis has become significant with increase maritime traffic volume and expansion of VTS coverage area. In addition, maritime traffic analysis is also applicable in the safety assessment of port facilities and the VTS (Vessel Traffic Service). In this paper, we propose a method to analyze the vessels' traffic pattern by using the heat map and the centroid method. This method is efficient for the analysis of the vessel trajectory data where spatial characteristics change with time. In the experiments, the traffic density and centroid by time have were analyzed. Trajectory data collected at Mokpo harbor was adopted. Finally, we reviewed the experimental results to verify the feasibility of the proposed method as a maritime traffic analysis method.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.7
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• pp.783-790
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• 2017

An acceptable proximity assessment collision probability is widely considered to be less than $10^{-4}$ in maritime traffic safety audit schemes. In the 1970s, Fujii, Macduff and colleagues introduced various models for collision probability of aberrancy in the community. Although existing studies ensured acceptable proximity collision probability, around $10^{-4}$, they were constrained by assumptions. A lack of support for the proximity probability criterion has been investigated in this study for practical use. The appropriate proximity probability for different size vessels in both straight and curved lanes has been analyzed based on GICOMS data. As a result, reasonable proximity collision probabilities were determined for various vessel traffic conditions. Accordingly, necessary improvements in the maritime traffic system have been suggested in consideration for various maritime traffic situations and conditions.