시스템 다이내믹스 기반 해양구조물 FEED 검증 방법에 관한 연구

황존규 목포해양대학교대학원 2021 국내박사

해양구조물에 대한 세계의 수요는 에너지 수급 메카니즘에 의해 결정되고, 세계 에너지 수요는 세계 경제 성장과 밀접하게 연관되어 있다. 즉, 세계 경제 성장에 따라 해양구조물에 대한 수요가 영향을 받고, 보다 직접적으로는 유가와 원유 생산량에 따라 수요가 변화한다. 이러한 원유의 생산은 육상 유전의 시추가 성숙 단계에 있는 반면 해양의 유전 개발은 성장 단계에 있기 때문에 장기적으로 시장이 매우 밝다고 볼 수 있어 개발의 필요성이 높다. 전통적으로 한국의 조선 해양산업은 타 경쟁국에 비하여 건조 기술에서 우위를 점하고 있지만, 해양구조물 설계기술의 핵심인 엔지니어링과 FEED 기술이 부족하고, 특히 개념설계와 기본설계 그리고 FEED의 역량은 매우 부족한 실정이다. 따라서 이러한 해양구조물 FEED 분야의 역량을 높이기 위해서 본 연구에서는 시스템 다이내믹스를 기반으로 하여 해양구조물 탑사이드 장비인 분리시스템(Separation System)을 대상으로 FEED 검증 방법에 관한 연구를 수행하였다. 해양구조물 분리시스템은 부가가치 측면에서 EPC(Engineering, Procurement and Construction) 프로젝트의 성공 여부를 결정할 수 있는 탑사이드(Topsides)의 가장 중요한 시스템 중 하나이다. 그럼에도 불구하고, 초기설계 단계에서 설계검증(Design Verification)에 대한 지금까지의 실태는 설계 작업의 진행이나 도면작성 및 제공에 국한되어 있어 초기설계(FEED;Front End Engineering Design) 과정에서 설계검증의 미흡으로 인하여 계약 후 잦은 설계변경에 의한 추가손실이 발생 되어왔다. 이러한 맥락에서 본 연구는 해양 구조물의 전체 프로젝트 수행 기간에 성공적인 사업수행을 도모하고 추가손실을 줄이고자 FEED 검증모델을 구축하여 시뮬레이션 후 그 결과를 현업에 적용하도록 하였다. 또한, 계약 전에 필히 FEED 검증을 수행하고 계약 후 상세설계 수행 시 설계변경이 최소화될 수 있도록 검증모델을 적용하였다. 제안된 설계검증 방법은 상세설계의 효과적인 실행뿐만 아니라 초기설계 단계에서 기술적 오류나 불일치 사항을 미리 찾아냄으로써 해양구조물의 엔지니어링, 구매조달 및 건조에 대한 경쟁력을 향상시키는 데 기여 할 것으로 예상한다. 이를 위하여 본 연구에서는 첫째, 시스템 다이내믹스의 인과요인 분석을 통하여 해양구조물 FEED 검증 방법을 구현하고자 FPSO 상부구조의 분리시스템(Separation System)을 대상으로 설계검증 모델을 적용하였다. FPSO는 부유식 원유 생산/저장/하역하는 해양구조물로서 시추선에 의해 개발이 완료된 유정과 연결하여 원유를 뽑아 올려 1차 분리 과정을 거친 후 Hull의 Cargo Hold에 저장했다가 유조선에 옮겨주는 역할을 한다. 이는 크게 선체 부분(Hull)과 상부구조(Topsides)로 나눌 수 있고 상부구조에 연구대상인 분리시스템이 위치 하고 있다. 또한, 분리시스템의 설계검증 방법으로는 설계단계에서 문제의 정의와 설계검증의 변수 선정, 인과지도 작성 및 적용 그리고 타당성 검증 순으로 프로세스를 진행하였다. 인과지도 작성은 논리 분석 능력이 우수한 Vensim PLE를 이용하여 수행하였고 모델 구축에 필요한 정보는 FEED Data에서 Operation Condition을 얻었으며 Hysis Simulation Data에서 Fluid Composition 자료를 얻었고 Vendor Data에서 설계 요구사항(Design Requirement)을 얻어 적용하였다. 둘째, 시스템 다이내믹스를 기반으로 저유량도 상관성 분석에 의한 새 로운 설계검증 모델(OC-Model)을 구현하였다. 특히, 해양구조물 공사 시작 단계에서부터 운전 조건을 고려하여 FEED에 대한 설계검증을 수행하여 조기에 설계 문제를 해결하고 계약 후 설계변경이 감소할 수 있도록 시도하였다. 제안된 설계검증 방법은 상세설계의 효과적인 실행뿐만 아니라 초기설계 단계에서 기술적 에러나 불일치 사항을 미리 찾아냄으로써 해양구조물의 엔지니어링, 조달 및 건조에 대한 경쟁력을 향상시키는 데 기여 할 것으로 예상한다. 결과적으로, 제안된 설계검증 방법이 해양구조물의 다른 핵심장비에도 확대 적용될 수 있으며, 향후 해양 프로젝트의 성공적인 수행에 의한 이익창출을 도모할 수 있을 것이다. 또한, 해양구조물 건조 시 설계변경에 의한 막대한 손실을 최소화 할 수 있을 것으로 기대한다. 결론적으로 본 연구를 통해서 첫째, 설계 오류를 조기에 찾아낼 수 있도록 하였고 둘째, 초기 설계검증에 의한 설계변경을 최소화 할 수 있도록 하였으며 셋째, 짧은 기간 내에 설계검증을 수행하여 입찰에 임할 수 있도록 하였다. 넷째, Vendor 데이터를 참고하여 상부구조의 핵심장비인 분리시스템에 대한 설계검증 Check list를 만들어 프로세스 엔지니어가 쉽게 사용할 수 있도록 하였다. 또한, 제안된 설계검증 모델의 확대 적용을 도모하고자 압축기(Compressor)와 열교환기(Heat exchanger/Cooler)에도 검증항목을 만들어 장비별로 설계검증이 이루어질 수 있도록 하였다. 이처럼 본 연구에서 제안한 방법(OC-Model : Operating Condition을 고려한 모델)을 적용할 경우 신속하고 체계적인 설계검증이 이루어질 수 있을 것으로 판단한다. 기대효과로는 제안된 설계검증 방법을 활용하여 상세설계의 효과적인 실행뿐만 아니라 초기 설계단계에서 기술적 에러나 불일치 사항 그리고 기술적으로 불충분한 사항을 미리 찾아냄으로써 해양구조물의 엔지니어링, 조달 및 건조에 대한 경쟁력을 향상시키는 데 기여 할 것으로 예상한다. 결과적으로, 제안된 설계검증 방법이 해양구조물의 FEED 검증 프로세스에 쉽게 적용될 수 있어, 향후 해양구조물 프로젝트의 성공적인 수행에 의한 이익창출을 도모할 수 있을 것이다. 또한, 해양구조물 건조 시 설계변경에 의한 막대한 손실을 최소화 할 수 있을 것으로 기대한다. 앞으로 이 방법을 FPSO 상부구조의 핵심장비인 압축기(Compressor)와 열교환기(Heat exchanger) 뿐 만 아니라 펌프(Pump)와 유틸리티 장비에도 확대 적용하여 그 효용성을 증가시킬 예정이다.

LP-SCR 시스템의 선박 적용에 관한 연구

최지만 목포해양대학교대학원 2021 국내석사

According to the atmospheric environment regulation of the International Maritime Organization (IMO), the direction of shipbuilding and shipping industries has changed. As emission regulations are already formulated, regulations on nitrogen and sulfur oxides are being implemented, and the scope of implementation will gradually expand to the emission control area. The development of carbon-neutral global policies to prevent global warming indicates that the future industrial direction will prioritize eco-friendliness, and in particular, the significant transition from the petroleum industry that causes global warming to eco-friendly energy. There is no choice but to face the task ahead. Already, higher levels of emission regulations have been established in the automotive industry. Leading companies are preparing to switch to eco-friendly and convenient power sources by reducing production lines for internal combustion engines and expanding production lines for electric vehicles and hydrogen cars. This approach is becoming a reality that should soon be directed to ships transporting large cargoes. However, the transition to eco-friendly ships is unlikely to occur immediately, as ships are not easily converted and discarded but are built with large invested capital and are regularly repaired and inspected when built for approximately 20 years. In this study, we aim to investigate the current status of air emission regulations for ships, their impact on the human body and the environment, the regulatory trends, and commercial, technological methods designed to reduce air emissions. The study will focus on nitrogen oxides, which are currently under regulation. Selective catalytic reduction (SCR) is a typical method of reducing nitrogen oxides. SCR is divided into high-pressure SCR and low-pressure SCR (LP-SCR), depending on if it is installed at the front or rear of the turbocharger of the ship engine. In Mokpo National Maritime University's training ship, Segero, an LP-SCR installed at the rear end of the ship engine supercharger owing to the ship structure characteristics, requires space flexibility. It will be verified whether the NOx reduction performance of the ship satisfies the IMO emission regulations. We will investigate the installed LP-SCR specifications, system configuration, system operability, and whether it satisfies the emission regulation requirements during actual operation. Furthermore, we will examine the LP-SCRs exhaust mounted on the main and generator engines and perform analysis using gas measurement data. In addition, the problem of back pressure raised by mounting a post-treatment device will be verified, and possible improvements to satisfy the requirements of future emission regulations will be evaluated and considered.

Design of an Algorithm for Solving the Navigational Collision Risk Based on the Vulnerability of Maritime Accidents Using

Yancai Hu 목포해양대학교대학원 2019 국내박사

Abstract Since 2016, Korea has promoted the research & development project to build the SMART-Navigation system for the SOLAS ships as well as fishing boats and other small ships to provide the LTE-Maritime communication network for non-SOLAS ships in order to reduce maritime accidents. The services of the SMART-Navigation project include monitoring assistance service for high risk ships. This service focuses on the vulnerable situation awareness, risk assessment and accident response. In this paper, a novel algorithm is proposed for the navigational Collision Risk (CR) solving system based on vulnerability of maritime accidents by using fuzzy logic for SMART-Navigation. Maritime vulnerability is defined as the possibility of a marine accident or degree of risk of marine accident. The factors of vulnerability are integrated with basic collision risk to expand the validity and enhance the utilization of collision risk assessment in the real scenario. This navigational collision risk solving system is consisted of four components. In the first module, as two main factors, distance to closest point of approach (DCPA) and time of closest point of approach (TCPA)are inferred for basic collision risk using fuzzy logic. The factors of vulnerability include bad weather, strong tidal current, accidents prone area, traffic congestion, operator fatigue and fishing boats operating area. The number of accidents occurred during 10 years in 159 waterways and the data of six factors of vulnerability in Korea are collected and analyzed by using fuzzy C-means clustering method. Based on the results from the project research team, variables related to six vulnerabilities are selected. Wind speed and wave height are the input variables for the bad weather factor. In order to consider the influence of weather condition for different sizes of ships. The singleton fuzzy reasoning logic is utilized, thus tuning algorithm is inserted to adjust the consequence of reasoning engine. The factor of strong tidal current refers to the tidal current speed and the accidents in the past 10 years. In the accident-prone areas, two input variables are selected for the reasoning engine using static ratio of accident number per hour in a day the past 10 years and dynamic ratio of passing ship’s number per hour. To solve the factor of congestion of shipping traffic, Static Congestion Degree (SCD) and Dynamic Congestion Degree (DCD) are considered at the same time. As we know, the operator fatigue is an important reason for collision accidents. According to the survey, time of working and navigation and tonnage of fishing vessel are chosen as the variables of the reasoning system. The distance to the center of fishing area and the size of fishing area are combined for the last factor of vulnerability. Additionally, the results of the six factors of vulnerability are integrated to calculate the combined vulnerability using Analytic Hierarchy Process (AHP) method. Then, two concepts of basic collision risk and vulnerability are incorporated to obtain the navigational collision risk. In the simulation, ten areas are chosen from 159 narrow waterway areas to examine the validity of this navigational collision risk solving system. In each area, the input variables are used to infer the vulnerability for the factors. These results are combined by using weighted average method. The threshold value of the navigational collision risk solving system is set to alert the dangerous encounter for the service of accident response.

필리핀 연안해운 안전정책 개선 연구

다이와 랜돌프 로이드 목포해양대학교대학원 2021 국내석사

Maritime Transportation is an important resource in a country like Philippines. Philippines a country which is composed of many small islands use ships as their main way of domestic trade. Small cargo ships to transport goods and services, passenger ships to carry tourists and locals, fishing boats and the like. In connection to this, there are accident and incidents that happened in the past that cannot be neglected, such as the asia’s titanic, wherein millions of lives were lost. Additionally there are collision, grounding, lack of AIS, and etc. Furthermore, the port facility infrastructures are in need of update, Aids to Navigation equipments are malfunctioning, lack of Vessel Traffic Management Systems to monitor vessel entry and exit, insufficient government support for the coastal shipping and shipbuilding, IT systems and data sharing are not yet fully utilized in government agencies, etc. Also, Philippines’Aids to Navigation (AtoN) facilities reported that only 72.73% of lighthouses and 68.22% of lighted buoys are operating. Moreover, some of the facilities that do operate are so old and deteriorated that their possible malfunction or failure may cause accidents at sea. The main objective of this paper is to a) improve the maritime safety, b) to prevent new accident and marine pollution casualties and c) to save lives and property. Likewise, it aims to present reasonable guide to improve its policy specifically on Coastal shipping. The maritime policy in the Philippines is administered by the three Safety Administration Bodies. Marina is involved in the maritime safety of the vessels plying in the Philippine waters, ship inspection, training and education of seafarers, issuance of certificate and shipyard regulation and etc. Philippine Coast Guard is tasked to make the country territorial waters safe and secure from any act or form of criminalities. It is tasked primarily with enforcing laws within Philippine waters, conducting maritime security operations, safeguarding life and property at sea, and protecting marine environment and resources; similar to coast guards around the world. Philippine Ports Authority is to provide reliable and responsive services in ports, sustain development of communities and the environment, and be a model corporate agency of the government. Establish a mutually beneficial, equitable, and fair relationship with partners and service providers. Provide meaningful and gainful employment while creating a nurturing environment that promotes continuous learning and improvement. Establish a world-class port operation that is globally competitive adding value to the country's image and reputation. In order to achieve this purpose, survey questionnaire were distributed and collected from different government agencies, shipping agencies and training center and seafarers and due to financial concerns, the researcher’s respondents are limited to 200 participants based on the National Capital Region of the Philippines. The researcher conducted cross tab and chi square analysis to determine the factors that affect the quality of coastal shipping in the country. To understand the result of the analysis, the researcher made a analysis model. In the analysis model there are five independent factor and five dependent factors. The five dependent variables for this study which have been measured through questionnaire surveys are law and institutional systems, government support, IT systems, navigation systems and infrastructures and the dependent factors are Maritime Industry Authority, Philippine Coast Guard, Philippine Ports Authority, Shipping Companies & Training Center and Seafarers. If the dependent factors were higher, the value of the independent factors would increase as well. These improvements will result in better performance of service, increased safety of passengers and also will lead to the improvement of safety in coastal shipping. As a result, the researcher found out that there are problems that exist such as the law & Institutional Systems are not made for government convenience, it is not made for demands convenience, the present seafarer education & training systems for IMO STCW are not in the satisfactory for trainees, ship's safety inspections are not being carried out in accordance with a proper way & manner, it is not easy for the user to obtain or purchase navigation equipments, it is not easy for navigators to obtain a useful navigation information, IT systems for vessel entry & departure procedures are not being utilized, IT basis procedures of data statistics are not well utilized, the government is not supporting enough ship financing subsidy for new building vessels, the vessels cannot be purchased freely from foreign countries without any government restrictions, the government is not supporting various welfare improvement policy for seafarers, port facilities for coastal shipping is not in the satisfactory conditions, sea traffic management systems are not in the satisfactory conditions, etc. Key words: Shipping policy, Safety Policy, Navigation, Coastal Shipping

Logistic Regression을 이용한 선박 충돌 위험 정보 Classification Model 개발에 관한 연구

양영훈 목포해양대학교대학원 2021 국내박사

In the accident of a collision, the distance at which the other ship was first detection range was either not found or less than 1 mile, and it was investigated that the ship operator did not recognize the ship's approach until the impending collision. As in the case of statistics, considering the situation in which the target ship is recognized from a very close distance in a collision accident, in order to prevent accidents, it is essential to secure sufficient first detection range and initial action in advance. In this study, The Risk Informed Classification Model (RICM) was developed that can recognize the encounter situation of the target ship from a sufficient distance in order to secure a first detection range to prevent collision between ships. For this study, a COLREG-based Encounter Classification Model (ECM) was applied to determine the ship's encounter situation, and based on the survey results in which experienced ship’s officer, using the Logistic Regression(one of the machine learning methods), developed a model that provides information and warning notifications to ship operators so that they can secure a first detection range from the risk of collision with other ships. Using Logistic Regression, developed a model 1 that judges whether collision risk information needs to be provided in advance for overtaking, crossing, head-on, and ambiguous encounter situations, and a model 2 that determines and provides information and warnings. As a result of verifying and analyzing the RICM model, it was analyzed that all of the dependent variables were statistically significant in the length and speed of the own and target ships, DCPA, Range, and TCPA used as independent variables. In general, the larger the size of the ship, the higher the ship speed, and the closer the distance to target ships, the more subjective risk the ship operator feels tends to increase, and it was confirmed that the RICM model similarly follows. The satisfaction of the captains who are currently receiving the RICM model collision risk information service in real time through the e-Navigation monitor was evaluated, and it was found that they were generally satisfied with the provision of collision risk information. In addition, it was suggested that it is useful in a situation of low visibility. As a result of comparing and analyzing maritime traffic data for ships receiving collision risk information by RICM model in real time and ships using general AIS, it was analyzed that there was no distinct difference. If information and warning notifications by the RICM model were received, it was expected that the passing distance with the other ship would increase, but the difference could not be confirmed. It was confirmed as a limitation that long-term observation and data acquisition are required to evaluate the traffic effect. This study is expected to serve as a basis for research on providing information to prevent future ship collision accidents. Continuous RICM model effect analysis, traffic evaluation, acquisition of additional learning data, and model advancement will contribute to the prevention of ship collision accidents.

동·하계 무안만 조하대 대형저서동물에 따른 건강성 평가

오준호 목포해양대학교대학원 2021 국내석사

The influx of many organic matter changes the benthic environment in which benthic organisms inhabit. Organic matter deposited in the sediment acts as an important food source, but mass influx of organic matter affects the habitats and survival of benthic animals. Benthic animals play an important role in purifying the benthic environment and are considered as important indicators of benthic environmental disturbances. Therefore, the community characteristics of benthic animals provide quantitative information on changes in the marine benthic environment. This study investigated the environmental characteristics and the distribution pattern of benthic animals, and assessed the benthic ecosystem using Marine Biotic Index (AMBI) and Water Quality Idex (WQI) in the subtidal zone of Muan bay, southwestern coast of Korea. Sampling was conducted at 10 stations in the subtidal zone of Muan bay at summer and winter. Surface seawater was sampled using Nansen bottle, and sediment was sampled by using Van Veen grab (0.05 m2). The collected samples were later analyzed for water and sediment quality, and benthic animals were classified. The average of grain size was 6.21Ø at summer and 5.91Ø at winter. The grain size tended to be finer at summer than that of winter. In the upper area of ​​Muan Bay, it showed a fine grain size composed of silt and clay, and in the lower area, it shows a corse grain size composed of sand. IL was 4.21% at summer and 4.25% at winter, showing no significant difference. The TOC was slightly higher at summer than that of winter, with 1.12% at summer and 0.78% at winter. These results showed that the upper area was finer in grain size than that of the lower area, and the organic matter content is higher. The total species number was 25 species at both summer and winter, and mean density of summer and winter were 94.90 ind./m2 and 52.60 ind./m2, respectively. In the upper area of Muan Bay, where the grain size was fine and organic matter content was high, annelida had dominantly appeared. However, in the lower area with coarse grain size and lower organic matter, mollusca and arthropoda were mainly appeared. WQI of Muan Bay was surveyed with an average of 23.6 (Very good; 1st grade). However, the S1 and S2 were showed an average of 37 (Moderate, 3rd magnitude) at summer. AMBI was surveyed with an average of 2.60 (Slightly polluted 2nd magnitude). However, the S2 was showed an average of 3.40 (Moderately polluted 3rd magnitude) at summer. From the cluster analysis, the benthic community was distinguished into three groups of upper, center and lower area of Muan bay. Also, the benthic community was divided into three groups by the correlation analysis with factors for benthic health assessment (WQI and AMBI). In the subtidal zone of Muan bay, there was a difference in the organic matter content according to the grain size, and it affected the distribution of benthic animals. As a result of this study, the health condition of the subtidal zone in Muan bay were good. However, from the results that benthic animals were not evenly distributed, and also the opportunistic species appeared, the load of organic matter in Muan bay seems to be increasing.

LMX2571을 활용한 자율해상무선기기 구현에 관한 연구

박청룡 목포해양대학교대학원 2021 국내박사

Even after the introduction of GMDSS, many maritime accidents and casualties are increasing. The representative method of transmitting a rescue signal when a person falls into the water on a ship is by pressing the V-Pass and VHF DSC buttons. In this case, it cannot be a complete solution. IMO and others have recognized the need for communication equipment for personal safety in addition to communication equipment for ship safety, and have been conducting research and consultations to introduce MOB. Among the WRC-19(World Radio Conference 2019) Agenda 1.9.1 “Regulatory measures within the frequency band 156-162.05 MHz for AMRD(autonomous maritime radio devices) to protect GMDSS and Automatic Identification Systems (AIS)”, VHF channels No.2006(160.9MHz) was newly allocated to AMRD applying AIS technology for class-B , including MOB devices. Therefore, it is essential to develop a device that meets the general conditions of class-B and MOB technology using AIS technology, reduces cost and is easy to carry. In this paper, an integrated device for miniaturization is selected for easy portability in the marine environment. AIS protocol implementation and message writing using microprocessor STM32L432 chipset, Gaussian modulation implementation using LMX2571 chipset and RF frequency 160.9MHz and terminal amplifier were designed. Currently used AIS is to transmit 8 slots of 4 each with 2 channels (AIS1 & AIS2), but in this paper, 8 bursts were transmitted using one channel (No. 2006, 160.9MHz), and ​ Eight slots were allocated to one burst, and transmission was performed. The commercial VHF receiver was set to receive conditions by setting the local channel 2006 with NMEA Command. Designed and verified according to general and technical conditions. As the saturation of the existing AIS channel approaches 50%, new frequency utilization is required, and a prototype was implemented based on international standards. In ITU-R M. 2135, the technical and operational characteristics of the transmitter are e.i.r.p. 100mW, they should not interfere with nor claim protection from other existing services, within the frequency tolerance ±500Hz, the spurious was met as -47dBm, and in this paper, the output was based on 30dBm. Also, it was confirmed that the VDM message was received through normal transmission for data transmission (RATDMA and ITDMA communication techniques) using one allocated channel 2006, and displayed in conjunction with ECDIS. The designed and implemented AMRD MOB-AIS will be a way to secure communication in the marine environment in the future. In particular, it is expected that it will play a key role in the safety of crew members in the efficient operating environment of leisure and fishing boats, training ships, and government ships. Research areas that need to be supplemented in relation to MOB-AIS devices in the future are research on transmission distance versus output, research on ways to expand the insufficient maritime mobile service identification code, and development of new application technologies such as radio buoys using AIS technology and institutional studies will be required. On the other hand, the marine distress location indicator MOB-AIS based on the AIS technology must be attached to the body of the survivor or to the lifejacket, so it is necessary to downsize with the integrated circuit design must be introduced, and technical support such as this study is essential.

평수구역을 운항하는 카페리선박의 차량고박 기준에 관한 연구

강병선 목포해양대학교대학원 2021 국내석사

The importance of cargo lashing has been raised after passenger ship sinking accidents due to failure of vehicle and cargo lashing and transshipment of cargo due to rolling. Accordingly, the code of equipment and structure of car ferries has been strengthened that all vehicles loaded on the car ferry that operate only in the smooth sea area, whose voyage time is less than 30 minutes and operate in the smooth or costal sea area, whose voyage time is less than 1 hour must be secured on the state of sea over 7m/s wind speed and/or over 1.5m wave height. Currently, the relevant contents have been changed to the code of cargo loading and securing, etc., on 2nd January 2015 and the systematic process for verifying the validity of securing is described according to the Annex 1, Standards for Cargo Stowage and Securing, Etc. Since this code accepted the contents of the IMO CSS(Code of Safe Practice for Cargo Stowage and Securing) and applies the external force acting on ocean sailing vessels, it is considered to be practically unreasonable to apply it to ships sailing in the domestic coastal sea area. This is because ships sailing in the coastal sea area exhibit relatively smaller hull motion than ships sailing in the ocean due to the geographical characteristics of the coastal sea area. Therefore, in this study, the hull motion of a ferry passenger ship that is not enclosed in a vehicle area sailing in the coastal sea area was measured and after comparing and analyzing the result of the hull motion calculation program(NSM), the external force according to rolling & pitching was applied to the vehicle loaded on the ship. Examining the lashing standards for car ferry ships sailing in the coastal sea area by comparing the external force with the bearing capacity that the vehicle can withstand without securing, it was found that loaded vehicles did not slip or tip over on the state of sea over 7m/s wind speed, 1.5m wave height and also, it is considered that the current lashing standards could relax after further study.

LNG bunkering 작업 시 가스누출 시나리오에 따른 피해영향평가

정희원 목포해양대학교대학원 2021 국내석사

In order to reduce air pollution and greenhouse gases, marine environmental regulations are being strengthened globally. As marine environmental regulations are strengthened, shipping industries are increasingly interested in LNG bunkering ships and LNG fueled ships as a way to reduce air pollution and greenhouse gases. Accordingly in this study were evaluated using the areal location of hazardous atmospheres when natural gas leaked owing to the damage of pipeline in a LNG fueled ship at Aewol port, jeju. Damages caused by flash fire, overpressure, and thermal radiation based on variables(ambient temperature, leakage hole size, pipe length, pipe pressure, pasquill stability, wind speed) were analyzed. From the results, regardless of variables, the damage range attributed to flash fire was the most significant, followed by overpressure and thermal radiation. It can be seen that the range of damage from flash fire and overpressure is most affected by pipe pressure and atmospheric stability, and the range of damage from thermal radiation has relatively little effect regardless of variables. In this study, when a fire or explosion occurred in Aewol port, it was found that it could affect up to 640m and confirmed that it should be equipped with gas alarm system, fire detector, automatic gas shut-off system and alarm system.

소형선박의 친환경성능 평가를 위한 온실가스 배출량 시뮬레이션

정숙현 목포해양대학교대학원 2019 국내석사

Abstract Active researches and developments have been made in many industrial sectors as international efforts have become unavoidable for air pollution which has been accelerated by industrialization. Together with this, strong regulations have also been implemented for sustainable growth. In the maritime industry which accounts for majority of international logistics, regulation against air pollution for the ships over G/T 400-ton has been implemented by the IMO. MARPOL 73/78 Annex 6 which regulates the reduction of greenhouse gases emitted by ships especially contains EEDI (Energy Efficiency Design Index), EEOI (Energy Efficiency Indicator) and SEEMP (Ship Energy Efficiency Management Plan) which measure greenhouse gas emissions in technical and operational terms and indicate their effects. By managing the efficiency of logistics volume through these indexes, it has shown improvement in environmental effect through numerous studies on such various areas as engine development, optimization of ship shapes, substitution of biofuels and route optimization. In the case of vessels with less than G/T 400 tons which are excluded from the regulation, however, environment-friendly measures solely depend on the efforts of each country. Though they account for meager 13% of GHG emissions from marine transportation, their emission per ton exceeds that of container lines and tank lorry vehicles, which makes the problem urgent. To solve this problem, Korea has been developing electric propulsion for small ships, installing LED lights for attracting fish school and implementing fishery closure and the designation of low-speed operation in the port areas. However, these somewhat circumventive and indirect methods are considered unlikely to achieve effective results in any serious ways. In order to effectively measure the indicators which can practically judge environment-friendly effects of small ships, this study defines a method which measure the exhaust gas discharged from the engines even when the ships’ operating conditions are changed and examines its effectiveness through case studies. This study proposes a simulation method to measure greenhouse gas emissions to assess environmental impact applicable to small vessels in consideration of the fact that the main engines of the small ships are very diverse unlike the large merchant ships and loading statuses and speeds are varied. In addition, by comparing and analyzing its effects and differences, study also verifies the effectiveness of the proposed method which is an improvement of the method using LCA so far implemented as an assessment tool for environmental effect for small ships.