• Ocean Systems Engineering
• /
• 제9권3호
• /
• pp.261-285
• /
• 2019

Nowadays in offshore industry there are emerging hazards with vague property such as act of terrorism, act of war, unforeseen natural disasters such as tsunami, etc. Therefore industry professionals such as offshore energy insurers, safety engineers and risk managers in order to determine the failure rates and frequencies for the potential hazards where there is no data available, they need to use an appropriate method to overcome this difficulty. Furthermore in conventional risk based analysis models such as when using a fault tree analysis, hazards with vague properties are normally waived and ignored. In other word in previous situations only a traditional probability based fault tree analysis could be implemented. To overcome this shortcoming fuzzy set theory is applied to fault tree analysis to combine the known and unknown data in which the pre-combined result will be determined under a fuzzy environment. This has been fulfilled by integration of a generic bow-tie based risk analysis model into the risk assessment phase of the Risk Management (RM) cycles as a backbone of the phase. For this reason Fault Tree Analysis (FTA) and Event Tree Analysis (ETA) are used to analyse one of the significant risk factors associated in offshore terminals. This process will eventually help the insurers and risk managers in marine and offshore industries to investigate the potential hazards more in detail if there is vagueness. For this purpose a case study of offshore terminal while coinciding with the nature of the Caspian Sea was decided to be examined.

• 한국해안해양공학회지
• /
• 제12권2호
• /
• pp.96-106
• /
• 2000

최근에까지 대형구조물이 해양공간이용의 목적으로 외해공항 및 해양터미날로 건설되어 왔다 그러나 때로는 이와같은 큰 규모의 구조물은 파량에 대해 현저한 벽으로 작용하게 되고 해안에 심각한 침식현상을 야기하게 된다 본 연구는 해안선으로부터 각기 다른 거리에 외해구조물을 건설할 때에 해저지형변화를 다룬 것으로 일련의 3차원 이동상실험으로 상세히 조사하였다 또한 해빈류와 외해구조물 배후의 국소침식과의 관계를 분명하게 하기 위하여 수리모델실험과 같은 규격으로 Boussinesq방정식 모델로 해빈류를 계산하고 비교하였다.

• 한국농촌건축학회논문집
• /
• 제20권1호
• /
• pp.85-92
• /
• 2018

Although Jeju is the best cruise Secondary port in Northeast Asia, currently there are no dedicated cruise terminals. The port international passenger terminal opened in 2015 has a ferry terminal for offshore passengers and a cruise passenger function. Jeju Island is therefore constructing a cruise only terminal with the aim of opening in 2018 to meet the growing passenger demand at the Seoguipo civilian and public ports along with construction of a naval base at Gangjeong Port in Seogwipo City. It also plans to build cruise docks and cruise terminals in the Jeju New Port according to the Jeju port construction basic plan. However, during the construction and planning process of cruise terminals in Jeju, the adequacy of the terminal size is being debated and the immigration facilities are being operated. Therefore, the study analyzed the size of terminals and operation of immigration facilities appropriate for cruise passenger demand by investigating the status of cruise related facilities and operation in Jeju area. Based on this, the Commission hopes to explore the rational direction of the cruise terminal plan to revive the cruise industry in Jeju and provide high quality service to cruise passengers.

• Journal of Advanced Marine Engineering and Technology
• /
• 제39권10호
• /
• pp.1037-1043
• /
• 2015

In recent years, Floating Liquefied Natural Gas (FLNG) Unit have attracted considerable attention. Generally, liquefied natural gas (LNG) units are produced in onshore liquefaction terminals from gas supplied from onshore gas fields or large-scale offshore gas fields near the coast. However, the development of these gas fields has approached saturation. Large-scale offshore gas fields far from the coast, as well as undeveloped medium- and small-scale offshore gas fields, have recently attracted attention. Among several proposed concepts, the floating LNG plant in the form of the FLNG system was chosen for further evaluation and development, considering worldwide receiving infrastructure. The design of a 2.5 million tonne per annum FLNG unit has been completed with a capacity corresponding to that of modern onshore liquefaction plants. Various simulation tests were performed to evaluate the performance of the electrical power plant, focusing on the efficiency of the electrical system to secure the aspects of plant safety. This design study analyzes the electrical system for the FLNG unit to improve the safety of operation and maintenance in the field.

• 한국항만경제학회지
• /
• 제28권3호
• /
• pp.27-44
• /
• 2012

세계 각국은 신재생 에너지 가운데 해상풍력 발전에 국가적 역량을 집중하면서 해상풍력 터빈의 용량을 대형화하고 있다. 특히 해상풍력 터빈은 부피와 중량이 큰 특징이 있어 육상운송에 어려움이 있어 해상풍력 전용항만이 필요하다. 따라서 본 연구에서는 국내 해상풍력 단지가 성공적으로 조성 및 운영될 수 있도록 최적의 전용항만 입지선정에 영향을 끼치는 평가항목을 분석하여 국가정책 의사결정에 올바른 방향을 제시하고자 하였다. 이를 위해 Fuzzy-AHP 기법을 적용하여 평가항목 별 중요도를 도출하였다. 평가항목은 수준 I에서는 5가지, 즉 집적 요인, 지역 요인, 경제 요인, 입지 요인, 컨소시엄 요인이 선정되었다. 이 가운데 집적 요인 37.4%, 입지 요인 34.2%, 경제 요인 24.5%가 주요한 항목으로 분석되었다. 그리고 수준 II에서는 각 요인에 3가지 항목이 선정되어 모두 15개 평가항목이 선정되었다. 분석 결과를 보면, 해상풍력 전용항만 입지 선정에 있어서 핵심적으로 고려되어야 할 항목은 풍력산업의 집적도, 항만운영의 경제성을 확보하는 물동량 규모, 해상풍력 관련 산업의 발달 정도, 그리고 개발될 해상풍력 단지와의 근접성으로 나타났다. 즉 해상풍력 전용항만 건설은 항만건설 측면과 해상풍력 터빈 제조기업의 입지 선호지역을 복합적으로 고려해야 한다는 의미이다. 따라서 정부가 해상풍력 전용항만을 건설함에 있어서 풍력터빈 제조기업의 의견을 충분히 반영하는 것이 요구된다.

• 가스산업과 기술
• /
• 제5권1호
• /
• pp.39-47
• /
• 2002

With the expansion of natural gas demands in many countries, the necessity of LNG receiving terminals has been increased. The offshore LNG Floating Storage and Regasification Unit (FSRU) attracts attentions not only for a land based LNG receiving terminal alternative, but also for a feasible and economic solution. Nowadays, as the reliability of offshore oil and gas floating facilities and LNG carriers gains with proven worldwide operations, the FSRU can achieve a safety level that can be comparable to an onshore terminal. The design development related with safety features of the FSRU has been extensively carried out by oil and gas companies, shipyards, engineering companies, and equipment vendors, and has been successful so far in many fields. The construction of the FSRU can be achieved by integrating various technologies and experiences from many disciplines and many participating companies and vendors. In this paper, reviews on some of the important design features and design improvements on FSRU together with the practical construction aspects in cargo containment, vaporization system, ESD system, and operation modes, have been covered in comparison with actual LNG carrier, onshore receiving terminal, and FPSO systems. In order to materialize an FSRU project, the technical and economic justification has to be preceded. It is believed that once the safety and technical soundness is convinced, the FSRU can bring a higher project feasibility by reducing the overall construction time and cost. Through this study, an FSRU design readily applicable to an actual project has been developed by incorporating experiences gained from many marine and offshore projects. The wide use of proven standard technologies adopted in the series construction of LNG carriers and offshore FPSOs will bring the project efficiency and reliability.

• 한국항해학회지
• /
• 제17권1호
• /
• pp.61-78
• /
• 1993

Large offshore structure are to be considered for oil storage facilities , marine terminals, power plants, offshore airports, industrial complexes and recreational facilities. Some of them have already been constructed. Some of the envisioned structures will be of the artificial-island type, in which the bulk of structures may act as significant barriers to normal waves and the prediction of the wave intensity will be of importance for design of structure. The present study deals wave scattering problem combining reflection and diffraction of waves due to the shape of the impermeable rigid upright structure, subject to the excitation of a plane simple harmonic wave coming from infinity. In this study, a finite difference technique for the numerical solution is applied to the boundary integral equation obtained for wave potential. The numerical solution is verified with the analytic solution. The model is applied to various structures, such as the detached breakwater (3L${\times}$0.1L), bird-type breakwater(318L${\times}$0.17L), cylinder-type and crescent -type structure (2.89L${\times}$0.6L, 0.8L${\times}$0.26L).The result are presented in wave height amplification factors and wave height diagram. Also, the amplification factors across the structure or 1 or 2 wavelengths away from the structure are compared with each given case. From the numerical simulation for the various boundary types of structure, we could figure out the transformation pattern of waves and predict the waves and predict the wave intensity in the vicinity of large artificial structures.

• 한국항해항만학회지
• /
• 제45권3호
• /
• pp.130-137
• /
• 2021

본 연구의 목적은 울산 부유식 해상풍력발전단지를 대상으로 서식지 등가성 분석법(Habitat Equivalency Analysis : HEA)을 적용한 가치평가를 통해 해당 해양공간 특성평가를 위한 객관적인 평가기준 제시에 있다. 울산 부유식 해상풍력발전단지 설립으로 인해 사용이 금지된 해역(5,017.6ha)에서는 상업적 피해, 생태계 파괴 등 여러 피해가 발생한다. 피해의 경제적 가치 규모 산정을 위한 대체 복원사업을 인공어초사업으로 선정하고 이를 HEA로 추정하였다. 추정 결과, 사회적 할인율 4.5%, 4년째부터 성숙도 100%를 기본 가정으로 한 경우 피해액은 약 457억원으로 나타났다. 본 연구에 사용된 HEA는 객관적이고 명확한 DATA를 기본으로 가치를 산정하기 때문에 해양공간 특성평가 시 발생할 수 있는 불합리성을 해결할 수 있을 것이다. 따라서, 본 연구의 결과는 향후, 해양공간계획의 시행에서 발생 가능한 이해관계자들 간의 갈등 해소에 도움이 될 것이다.

• 한국항만경제학회지
• /
• 제37권3호
• /
• pp.93-104
• /
• 2021

육지와 섬을 잇는 역할을 하는 여객선은 섬에 거주하는 섬 주민과 섬을 방문하는 관광객이 많이 이용하고 있다. 그래서 편리하게 이용할 수 있도록 도심과 접근성이 좋은 곳에 위치하고 있다. 그러나 고령화 된 섬 주민과 일반 관광객이 이용하기 편리한지 여객선터미널에 대한 시설특성과 보행환경에 대한 연구는 이루어지지 않았다. 이 연구에서는 여객선터미널이라는 공간을 중심으로 여객선터미널의 접근성, 여객선터미널 이용을 위한 시설특성, 여객선터미널에서 여객선 승하선과 여객선 안에서의 보행환경으로 보행구간을 설정하였다. 보행구간별 보행환경을 측정하기 위해 측정툴을 개발하고 여수연안여객선터미널을 대상으로 이용객의 중요도와 만족도를 IPA기법을 이용하여 분석하였다. 그 결과 여객선터미널 접근 과정에서는 '걸어서 대중교통 이용의 편리성', '여객선터미널의 위치와 방향을 안내해 주는 이정표 이용 편리성'이 집중영역으로 조사되었다. 반면에 여객선터미널 내부의 시설특성과 보행환경은 이용객들의 만족도가 높게 나타났다. 여객선터미널에서 여객선까지 보행환경에 있어서는 '보행로의 표면 보행환경', '짐을 가진 상태에서 보행 편리성', '부두 경사구간 보행 편리성', '여객선 램프 구간의 보행 편리성'이 만족도가 낮게 나타났다. 여객선 안에서의 시설특성과 보행환경에 있어서는 '계단 바닥 상태에 따른 보행 편리성'이 만족도가 낮게 나타났다. 이 연구는 여수연안여객선터미널의 시설 및 보행환경 개선을 위한 기초자료로 활용할 수 있으며 다른 지역의 연안여객선터미널과 비교연구를 위한 자료로 이용될 것으로 기대된다.

• Journal of Information Processing Systems
• /
• 제10권1호
• /
• pp.103-118
• /
• 2014

Over the last couple of years, traditional VANET (Vehicular Ad Hoc NETwork) evolved into VANET-based clouds. From the VANET standpoint, applications became richer by virtue of the boom in automotive telematics and infotainment technologies. Nevertheless, the research community and industries are concerned about the under-utilization of rich computation, communication, and storage resources in middle and high-end vehicles. This phenomenon became the driving force for the birth of VANET-based clouds. In this paper, we envision a novel application layer of VANET-based clouds based on the cooperation of the moving cars on the road, called CaaS (Cooperation as a Service). CaaS is divided into TIaaS (Traffic Information as a Service), WaaS (Warning as a Service), and IfaaS (Infotainment as a Service). Note, however, that this work focuses only on TIaaS and WaaS. TIaaS provides vehicular nodes, more precisely subscribers, with the fine-grained traffic information constructed by CDM (Cloud Decision Module) as a result of the cooperation of the vehicles on the roads in the form of mobility vectors. On the other hand, WaaS provides subscribers with potential warning messages in case of hazard situations on the road. Communication between the cloud infrastructure and the vehicles is done through GTs (Gateway Terminals), whereas GTs are physically realized through RSUs (Road-Side Units) and vehicles with 4G Internet access. These GTs forward the coarse-grained cooperation from vehicles to cloud and fine-grained traffic information and warnings from cloud to vehicles (subscribers) in a secure, privacy-aware fashion. In our proposed scheme, privacy is conditionally preserved wherein the location and the identity of the cooperators are preserved by leveraging the modified location-based encryption and, in case of any dispute, the node is subject to revocation. To the best of our knowledge, our proposed scheme is the first effort to offshore the extended traffic view construction function and warning messages dissemination function to the cloud.