• 한국항만경제학회지
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• 제19권2호
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• pp.55-67
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• 2003

The purpose of this study is to estimate and forecast the marine trading volumes based on the structural model. We employ GPH cointegration test since the structural model must be stationary to get the accurate predicted values. The empirical results show that our model is stationary. This paper also applies variance decompositions and impulse-response functions to the structural model composed of exchange rate, domestic industrial activity, and world business. The results indicate that while both loading and unloading volumes respond positively to the shocks in income and then decay very slowly, their responses are different to the shocks in exchange tate.

• 한국환경보건학회지
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• 제50권3호
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• pp.169-180
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• 2024

Background: CAPSS missing evaporate emissions of volatile organic compounds (VOCs) from liquid cargo loading and unloading at ports. It needs to be supplemented to improve air quality management and allow more effective policy formulation. Objectives: In this study, the VOC emissions from the loading and unloading of liquid cargo at ports, which are not included in CAPSS, were estimated. The results of this study were compared and analyzed with the emission levels as described by CAPSS, confirming the need for managing VOC emissions from the loading and unloading of liquid cargo. Methods: Methodology provided by the U.S. Environmental Protection Agency (EPA) was applied to estimate the VOC emissions from the loading and unloading of liquid cargo at ports. The types of liquid cargo loaded at unloaded at ports are diverse, but for this study emissions were estimated for 37 VOCs designated by the Ministry of Environment. Results: The estimated results for VOC emissions from liquid cargo loading and unloading at domestic ports was 112,079 tons/yr, which was confirmed to be 11% of the known CAPSS emissions. The highest emissions were found from the loading and unloading of naptha, and the port with the highest emissions was Ulsan Port. Conclusions: The results of the estimated VOC emissions from liquid cargo loading and unloading at ports confirmed the high emission levels. To protect the health of port workers and nearby residents, it is essential to manage the emission sources and undertake continuous research.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1-6
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• 2007

The membrane type LNG(Liquefied Natural Gas) cargo containment system is a special design structure for the large deformation behavior at LNG temperature$(-162^{\circ}C)$. The design of membrane is required great confidence so that membrane can plat role in the tightness of flammable fluid storing. LNG cargo containment is loaded and unloaded LNG between twice and five times in a week. During this process, the membrane has large deformation behavior due to the variation of temperature and pressure to the self weight. In this study, the evaluation of the fatigue strength of membrane is very important to determine the design life of LNG storage tank and to evaluate the mechanical properties at the LNG temperature. Also, in the view point of large deformation, the evaluation method is applied conservatively $\epsilon-N_f$ curve of SUS 304L.

• 유통과학연구
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• 제10권10호
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• pp.25-33
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• 2012

Purpose - The Garak agricultural wholesale market ('Garak Market') plays a central role in the distribution of agricultural products in Korea and is important in connecting consumers with producers. However, problems regarding inefficiencies and the high-cost structure of the wholesale market's distribution/logistical system are being raised in relation to severe competition among retailers. Furthermore, the service needs of retailers and market users are not being fulfilled due to the inconsistency of the wholesale market's functions and facilities, thus reducing the competitiveness of the market. In this regard, innovative changes are being requested of the agricultural wholesale market according to changes in the agricultural product distribution environment. In particular, the lack of unloading facilities and the outdated unloading system of the wholesale market must be improved to enhance system efficiency. Research design, data, and methodology - This study observed the problems of the unloading system of the agricultural wholesale market in order to present relevant measures for improvement. The need for unloading auctions was also researched in this study. The survey of 70 forwarders belonging to the producing district distributor association of the Garak market was conducted by post. Additionally, 20 auction dealers and 59 shippers and transporters were individually interviewed. The survey on the need for unloading auctions used five-point Likert Scales. The statistical analysis was conducted with SPSS WIN 12.0 software. Results - First, the wholesale market must employ members of the unloading labor union to allow these employees to directly manage the unloading process. Second, it is crucial to revise regulations to ensure that the principal agent pays the unloading cost according to the standard unloading cost system. Third, the vehicle auction carried out for certain vegetable products must be converted to the unloaded auction system. According to the related interviews with the wholesale market's distribution agents, whereas shippers and transporters recognized the need for unloaded auctions, auction dealers tend to have a negative view of this system. Furthermore, the stated reasons in favor of unloaded cabbage, radish, and other vegetable auctions were prevention of constraint, creation of transparent trade conditions, and reduction of corrected seller tickets. Many of the respondents answered that the transport cost reduction rate in unloaded auctions must be below 20%. Fourth, the unloading system must be mechanized and a detailed, reasonable plan must be provided to settle the existing conflict with the unloading labor union. Conclusions - The proposals in this study are expected to play an important role in improving the cargo handling system of the wholesale agricultural product market in the future. Improving the system is expected to help shore up the competitiveness of the industry. If all the related bodies closely cooperate with each other and work harder, taking advantage of the synergies created by the facility modernization project, the Garak market will play a pivotal role in the distribution of agricultural products.

• 한국빅데이터학회지
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• 제8권2호
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• pp.165-175
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• 2023

LNG는 인천항의 대표적인 수입화물로 인천항 전체 물동량 증감에 기여도가 상대적으로 높은 편이다. 또한, 국가적 차원에서도 LNG는 도시가스 및 전력발전에 필요한 핵심 자원으로 시장 수요의 변동 요인에 대한 분석과 적합한 수요예측모델의 구축은 LNG 기반 발전 계획 및 국가전력수급기본계획 수립 등에 매우 중요하다. 본 연구에서는 기존 연구들에서 다뤄지는 거시적 연간 자료를 통한 예측과 달리, LNG 운반선이 하역하는 주간별 물동량을 대상으로 주기성을 파악하고, 대내외 변동요인과의 상관관계를 분석한다. LNG 수요 변동요인으로는 주간 데이터의 계절성, 최대전력, 전력 공급예비력 등 전력 수급 데이터 등을 고려하였다. 또한 LNG 수요를 예측하기 위해 자료의 특성을 고려하여 주간단위별 LNG 물동량을 종속변수로 한 시계열 예측과 인공신경망 모형을 통한 예측 후 예측치에 대한 적합성을 검증 및 실적-추정치 간 오차비교를 통해 최적모형을 도출하고자 한다.

• 한국산업융합학회 논문집
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• 제23권3호
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• pp.393-401
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• 2020

According to the research and investigations performed on Port Facilities for cargo-works of hazardous materials around the Port of Busan, a conclusion was drawn that the manually operating foam tower monitors are ineffective as they are hard to access due to the radiant heat under contingency circumstances such as a fire. Moreover, in some cases, the effective range of Foam Tower Monitors are insufficient to reach docked ships and manifolds where hazardous materials are being unloaded. In addition, Dangerous Goods freights are inadequately and inefficiently stored regardless properties of hazardous substances due to complicated local regulations, and some are equipped with inapplicable facilities for docked ships. Therefore, in order to effectively counteract the contingencies and obtain safety, it would be recommended to install adequate facilities.

• 한국항해학회지
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• 제10권2호
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• pp.31-55
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• 1986

Generally, the development of shipping is characterized by the amount of traffic flow (traffic volume) and seaborne cargo in the sea. Movement of ships is an essential element of constructing the traffic flow which is represented the dynamic movement of ships in the sea, but on the other band the numbers of arriving and departing the port is the basic factor consisting of the static movement of ships. The amount of cargoes by coastal vessels and ocean trade vessels have increased tremendously with the great growth of the Korean economy these days. This increase of the seaborne cargoes has made the Korean coastal traffic flow so congested that this can be a cause of large pollution as well as great marine casualities such as a loss of human lives and properties . And also the future coastal traffic is expected to increase considerably according to our economic development and high dependence upon foreign trade. Under the circumstance, to devise the safety of coastal traffic flow and to take a proper step of a efficient navigation, there is a necessity for analyzing and surveying the coastal traffic trend and the characteristics of cargo movement. In order to grasp the dynamic movement of ships in the Korean coast, O/D analysis is executed. This paper aims to secure the basic data necessary for a comprehensive plan and estimation of vessel traffic management system for the enhancement of safety, order and efficiency of vessel traffic in the Korean coast. The analyzed results of the traffic flow and seaborne cargoes of the Korean coast are summarized as follows : 1) The congestion by the vessels occurred around the ports such as-in proportion of ship's number (proportion of tonnage) -Incheon 18.5%(14.8%), Pohang 5.9% (9.9%), Samil 5.2%(8.3%), Mokpo 8.6%(0.8%), Pusan 13.5%(36.4%), Ulsan 9.1%(16.2%). 2) It is found that the area adjacent to Incheon, Pusan, Ulsan, Channel of Hanryu and South-western area are heavily congested. 3) It is confirmed thatthe area adjacent to Incheon, Pusan, Ulsan, Channel of Hanryu and South-western area are heavily congested. 3) It is confirmed that the coastal vessels are main elements constituting the coastal traffic and that there are much traffic flow among five ports as following through the precise O/D analysis of ship's coastal movement. Incheon-Samil, Ulsan, Pusan, Jeju Pusan -Samil, Ulsan, Incheon, Jeju Pohang -Samil, Inchoen, Jeju Pohang -Samil, Incheon, Jeju Ulsan -Samil, Incheon, Jeju Samil -Ulsan, Pusan, Incheon 4) The amount of cargoes to abroad are in proportion about 81% of total and the amount of coastal cargoes are about 19%. Of those, cargoes in and out to Japan are about 26% and to South-east Asia are about 27%. 5) The chief items of foreign cargoes are oil(38.33%), iron ore(13.98%), bituminoous coal(12.74%), grain(8.02%), lumber(6.45%) in the import cargoes and steel material(21.96%), cement(17.16%), oil(6.81%), fertilizer(3.80%) in the export cargoes. 6) The 80.5% of total export cargoes and 92.4% of total import cargoes are flowed in five main ports. 7) The chief items of coastal cargoes are oil (42.45%), cement(16.86%), steel material (6.49%), anthracite(6.31%), mineral product(4.3%), grain, and fertilizer. Almost 92.24% of total import and export oil cargoes in Korea is loaded and unloaded at the port of Samil & Ulsan.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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• pp.468-476
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• 2001

The ROK TRANSCOM is trying to establish a concrete wartime sealift operation plan. But there are many problems to be solved for setting up the plan. The most serious problem is to procure war materiel to be shipped in U.S.A and next one is to determine the number of sealift assets and to allocate them. The process of sealift operation can be described as follows. Before the order of vessel mobilization, all vessels appointed for activation would be scattered in worldwide in the state of Beaded or unloaded. After the order of vessel mobilization, vessels would go to SPGE(seaport of embarkation) to load war materiel. Some loaded ships should offload the commercial cargo to the near port as soon as they are activated, before they would go to SPOE. All vessels would load procured materiel in SPOE and then go to SPOD(seaport of debarkation). They would offload war materiel in SPOD and then go back to SPOE to load war materiel again. We will simulate this process using ARENA(1), evaluate the sealift capability of ROK and find omit problems of the sealift plan. This model ultimately evaluates the sealift capability and provides planners with critical information far establishing and correcting the plan. This study can also provide military planners with a flexible and accessible decision support tool to provide advance planning under a variety of conditions on the sealift capability. The military planner is expected to make use of this model as a standard for establishing effective and concrete sealift operation in the near future. We can conclude how procurement capability significantly affects the result of sealift operation through this model. We could decide the appropriate levee of sealift asset such as the number of vessels and the number of available berth. So we could allocate effectively the resources for completing the sealift operation within the TGT(Target) time.

• 해양환경안전학회지
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• 제29권6호
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• pp.681-687
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• 2023

최적 운항자세 선정 기술이란 주어진 운항 배수량과 운항 선속에서 최소의 저항을 가지는 즉, 최적의 연료 소비 효율을 가지는 초기 선수흘수와 선미흘수를 제시하는 것이다. 본 논문의 주 목적은 대상선박의 유효동력 데이터를 기반으로 주어진 운항조건에서 최대의 에너지효율을 가지는 최적의 운항자세를 선정하는 프로그램 개발하는 것이다. 본 프로그램은 인공지능 기법에 의한 파이썬 기반 GUI(Graphical User Interface)로 작성되어 선주가 쉽게 사용할 수 있도록 하였다. 그 과정에 있어 대상 선박 소개, 전산유체역학(CFD)을 통한 유효동력 데이터 수집, 심층학습을 사용한 유효동력 모델 학습 방법 그리고 심층신경망(DNN) 모델을 응용한 최적 운항자세 제시 프로그램을 구체적으로 설명하였다. 선박은 운항 별로 화물을 싣고 내리게 되고, 이에 화물 적재량이 변화되고 배수량이 변경된다. 선주는 배수량 별 예상 선속에 따라 최소저항을 가지는 즉, 최대의 에너지효율을 가지는 최적의 운항자세를 알고자 한다. 개발된 GUI는 해당선박의 태블릿 PC와 앱에 설치하여 최적 운항자세 선정에 활용 가능하다.