• Journal of Korea Ship Safrty Technology Authority
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• no.7 s.25
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• pp.21-38
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• 2008

본 연구는 배의길이 24미터이상 40미터미만 어선에 대한 국내 복원성기준과 IMO의 IS Code 기준 및 외국의 기준을 조사하고 비교하여 IS Code 기준의 국내 수용 가능성을 검토하고 그 결과를 토대로 하여 국내실정에 적합한 복원성기준을 마련하는 것을 목적으로 한다. 따라서 국내외 어선의 L, B, D 분포, 상관관계 및 선형특성 등의 기초 자료를 조사하고, 우리나라, 미국, 영국 등 선진외국 및 IS Code의 어선복원성기준 비교 검토하여 IS Code의 복원성기준의 각 항목(요건)에 따른 차이점과 수용 시 문제점을 도출하였으며, 국내 어선의 업종별 실선자료 수집 및 적하상태의 복원성능 계산, 국내·외 기준을 적용한 업종별 실선의 복원성능 평가를 실시하였다. 이러한 연구 결과를 토대로 국내실정을 고려한 배의길이 24미터이상 40미터미만 어선 복원성기준(안)을 제안하였다.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.4_2
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• pp.661-667
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• 2020

The optimal shape modeling of core parts through 3D modeling and structural analysis for the development of small and medium-sized ships. The goal is to improve the efficient structure of the hydraulic system for controlling the rudder among the core steering parts in small and medium-sized ships. Through 3D modeling and structural analysis, a new concept of tiller parts and a double-acting hydraulic cylinder control system were proposed and operational structural stability was evaluated. Structural analysis of the three different tiller designs that can be replaceable onto existing fishing vessels was conducted to derive the final shapes. The emphasis was placed on evaluating the structural stability of the key drive components, the tiller, pin, and cylinder rodin the maximum torque condition of the hydraulic cylinder.

• Ocean policy research
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• v.33 no.2
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• pp.25-55
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• 2018

Cold storage and transportation facilities play major roles in the implementation of fishery cold chain systems. Most fishes are more easily perishable than other food products such as agricultural products and livestock products. Therefore, fishery cold chain systems were earlier introduced than other food clod chain systems. It is acknowledged that a reefer ship as a component of cold chain systems was used in the fishery transportation in the Joseon Dynasty. But researchers disagree on the introduction time of a fishery reefer ship. This study investigated the introduction time of a fishery reefer ship by some conditions including the number of private cold storage facilities, the magnitude of fishing vessels, and the plenty catch of fish species. According to reviewing the introduction conditions of fishery reefer ships, it was estimated that fishery reefer ships were introduced in 15th century. Therefore, the introduction time of a fishery reefer ship is more advanced about 300 or 400 years than as we know.

• Journal of Wind Energy
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• v.14 no.2
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• pp.5-13
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• 2023

As offshore wind farms are developed, the importance of cooperation with stakeholders such as fishermen from the initial phase is gradually increasing. This study developed a methodology that can promote the involvement of fishermen in the site feasibility review process. The spatial scope is Gunsan City, which is establishing an initial offshore wind project strategy. A survey was conducted for representatives of 12 fishing villages on the location preference for offshore wind farms. As a result, fishermen suggested negotiable or absolute opposite locations by examining a local sea map. Location preference seems to depend on the degrees of vitalization of fisheries using vessels. This study shows that fishermen can have reasonable opinions according to the location, not unconditionally, in initial discussions on offshore wind power. Investigating stakeholders with various positions is essential, and adjustments are needed for conflicting points in the future.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.267-274
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• 2018

A variety of appendages are attached to coastal and offshore fishing boats to improve stability during navigation or fishing operations (stability performance and roll reduction). These appendages are generally classified into three types, which are shown in Fig. 1. The numerical calculations were conducted for the following eight cases: one case of a bare hull, three cases where a single appendage attached, three cases of a pair of appendages attached, and one case where all three appendages were attached. Table 1 presents the main dimensions of the bare hull and Table 2 describes the main dimensions of the three appendages. The fluid dynamic performance with regard to the three hull appendages was evaluated via CFD for the following cases: each of the appendages attached independently, a pair of appendages attached, and all three appendages attached simultaneously. The No. 1 appendage showed that pressure resistance was proportionally greater than friction resistances. Both Nos. 2 and 3 appendages showed comparable levels of pressure and friction resistances. The correlation between appendages was minimal in the case of pairs and Comparing the cases of the No. 2 appendage attached and all appendages attached, at 11 kn, the EHP showed an difference of 9 %.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.5
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• pp.583-590
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• 2018

The objective of this study is to present a resistance performance map developed using the dimension parameters of a bilge keel appendage attached to a fishing vessel using CFD. The dimension parameters consist of three length and breadth measures of a bilge keel appendage from nine selected cases. The size of a bilge keel attached to an existing ship should be 90 % of the ship length and 5 % of the ship breadth. In this study, bilge keels with a length of 63 %, 77 % and 90 % and a breadth of 5 %, 7 % and 9 % were considered based on ship length and breadth. The effective power in each of the nine cases was predicted using CFD. Based on results from an existing ship, effective power in the case with the shortest length and longest breath was reduced by 0.3 %. The case with the longest length and breadth showed an increase in effective power of 1.7 %. The case with the shortest length and breadth showed a decrease in effective power of 2.3 %. The proposed map can be utilized to select dimensions according to the sailing and work patterns of fishing vessels from the perspective of resistance performance.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.2
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• pp.163-174
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• 2020

Particulate matter levels are rapidly increasing daily, and this can affect human health. Therefore, air pollutant emissions from sea vessels require management. This study evaluates the status of air pollutants, focusing on air pollutant emissions from the vessels of the Korea Coast Guard (KCG), and proposes national management measures to reduce emissions. According to a report recently released (2018) by the National Institute of Environmental Research (NIER), emissions from vessels constituted 6.4 % of the total domestic emissions, including 13.1 % NO_x, 10.9 % SO_x, and 9.6 % particulate matter (PM10/PM2.5). Among the rates of pollutant emission from vessels, the emission rates of domestic and overseas cargo vessels were the highest (50.6 %); the ratio of fishing boats was 42.6 %. With respect to jurisdictional sea area, 44.1 % of the emissions are from the south sea, including the Busan and Ulsan ports, and 24.8 % of the emissions are from the west sea, including the Gwangyang and Yeosu ports. The KCG inspects boarding lines to manage emission conditions and regulate air pollutant emissions, but it takes time and effort to operate various discharge devices and measure fuel oil standards. In addition, owing to busy ship schedules, inspection documents are limited in terms of management. Therefore, to reduce the air pollutant emissions of such vessels, regulations will be strengthened to check for air pollutants, and a monitoring system based on actual field data using KCG patrol ships will be established, for each sea area, to manage the emissions of such vessels. Furthermore, there is a need for technological development and institutional support for the introduction of environmentally friendly vessels.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.3
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• pp.157-165
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• 2000

A small hydraulic winch system with an automatic tension control unit was designed to improve the work efficiency of coastal small vessels and the dynamic response characteristics of the winch system operated in the open loop condition was investigated. The inlet and the outlet pressures in hydraulic motor, the torque and the rotating speed of winch drum were measured as a function of time, and the behaviour in autotension mode for stepped load changes was analyzed. The results obtained are summarized as follows : 1. The developed winch system for coastal small vessels will result in better fishing with improved efficiency and lower manpower consumption by remote control of winch system. 2. The rotating delay times of winch drum for on/off operations of solenoid valve were 0.09 see at CW mode and 0.04 sec at CCW mode, respectively. After the solenoid valve was controlled, response characteristics were unstable slightly but showed good tracking behaviour over short time. 3. The driving torque of winch system in autotension mode was kept almost constant of 55.9 kgf·m, and 11.1 then the rotating speed of winch drum was kept almost constant of 5.1 rpm in the larger torque than 55.9 kgf·m and 11.1 rpm in the lower torque than that. 4. The 5% settling times in the transient response characteristics of autotension mode under rapid increasing and decreasing conditions of load were 0.12 sec and 0.2 sec, respectively, and then the rotating speeds were 11 rpm and 5.3 rpm, respectively. 5. The tracking behaviour of torque and rotating speed by remote control operation were stable within 0.23 sec at CW mode and 0.37 sec at CCW mode, respectively.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.6
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• pp.635-641
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• 2019

Domestic southwest offshore wind farms have problems such as the reduction in fishing rights by prohibiting vessel traffic, which delays their development. As such, there is a need to develop offshore windfarms in Europe to permit the passage of vessels and fishing operations in specific offshore windfarm areas. In this study, we used the environmental stress (ES model) and the IALA Waterway Risk Assessment Program (IWRAP) to determine the ratio of risk to the route type (cross pattern, grid pattern) and traffic volume (present, 3 times, 5 times and 10 times) to derive the risk factors of specific vessels for offshore windfarms. As a result, ship operators' risk related to offshore windfarms did not rise in both route types and there was no significant difference in the annual probability of collision in the present traffic volume. In conditions that increased traffic volume by 3 times, 5 times and 10 times, the risk ratio increased as ship operator risk and collision probability increased at the crossing points. Furthermore, when the traffic volume of the ship increased, the risk could be more effectively distributed in the grid route compared to the cross route. The results of this study are expected to apply to the operation type, route operation method, safety measures, etc. in offshore wind farms.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.7
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• pp.801-809
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• 2017

The purpose of this study is to contribute to the prevention of ship collisions by investigating real ship collision cases and statistically analyzing causes of human error for captains and Officers of the Watch (OOW). This study encompassed a total of 109 cases for 218 vessels, which were suitable for the analysis of ship accidents between merchant ships or merchant ships and fishing boats over the 7 years from 2010 to 2016. Data was collected while classifying vessels according to type, Give-way and Stand-on vessels, along with the cause of human error. Factors causing human error were identified after focusing on the cause of each collision given by the OOW ; frequency and cross tabulation analyses were conducted using SPSS, a statistical analysis tool. As a result, the main causes of human error by an OOW in a ship collision situation were that lookout was neglected in a Give-way vessel including radar surveillance (74.3 %) or continuous observation of an opponent vessel was carried out (17.4 %). A major factor for Stand-on vessels was failure to act to avoid collision with another vessel (63.3 %). In particular, most neglect for lookout type merchant ships occurred after the opponent ship was first observed, and a common cause of lookout neglect and neglect of duty was a focus on other tasks during navigational watch time.