• Journal of Advanced Marine Engineering and Technology
• /
• v.29 no.3
• /
• pp.306-312
• /
• 2005

IMO $NO_x$ levels are generally possible to meet by means of primary on-engine measures. Further significant follow-on reductions are likely to require a secondary after-treatment technique. SCR(Selective Catalytic Reduction) technology is used almost exclusively for $NO_x$ removal in stationary combustion systems. In order to develop a practical SCR system for marine application on board ship, a primary SCR system using urea was made. The SCR system was set up on the ship, 'HANNARA' as a test vessel. employed a two-stroke cycle diesel engine as main propulsion, which is a training ship of Korea Maritime University. The purpose of this paper is to report the results about the basic effects of the below system parameters, The degree of $NO_x$ removal depends on some parameters, such as the amount of urea solution added, space velocity, reaction gas temperature and activity of catalyst.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.24 no.1
• /
• pp.134-137
• /
• 2020

Recently, there are emphasized to support the maintenance and management system of vessels using acquired data from engine part equipment. But, there are limitations for data exchange and management. To solve the problem, the ISO published ISO 19847 and 19848. In this paper, we analyze the ISO 19848 requirements related to identify data channel ID for ship equipment, and propose the examples for applying encoding techniques. In addition, we suggest the proposed technique for applying of managing the failure and maintenance type of the ship's engine part facilities by examples. If this method is applied, the vessel's equipment can exchange data through the sharing of the code table, and express what response is needed or acted, including where the failure occurred.

• Journal of Fisheries and Marine Sciences Education
• /
• v.29 no.3
• /
• pp.746-756
• /
• 2017

Marine accidents of fishing vessels occupied about 70.5% of the whole marine accidents in Korea from 1996 to 2015, this ratio was not much changed for a long time. A lot of efforts have been taken recently but marine accidents do not reduce. Therefore a fundamental counterplan to decrease accidents in fishing vessel is indispensable for reduction of whole marine accidents in Korea. Since the most frequent occurring accidents in fishing vessels were engine trouble and collision in statistics by KMST (1996~2015), the study focused on them. The cause of engine trouble were poor inspection and maintenance of the mechanical system. The greatest portion of marine accidents was collision, and the biggest cause of the collision was poor watch-keeping. The better watch-keeping will be the best way to reduce the accident. For this reason, it may be necessary for the navigator to make strict precaution on the other vessels under way systematically and keep the regulation for preventing collisions, and for an engineer on watch to make a check the mechanical system periodically for reduction the engine trouble. Instead of penalty, incentive about safe navigation will be helpful for reduce accident as if automobile insurance would do. In order to prevent engine trouble, the fisheries federation establish the repair center. Futhermore the development of autonomous navigation system is necessary to reduce the marine accident.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.43 no.2
• /
• pp.149-159
• /
• 2007

Marine casualties of fishing vessels were analyzed to reduce the sacrifice of human life using data of the Korean Maritime Safety Tribunal from 1995 to 2004 in Korea. The occurred number of fishing vessel casualties were likely to be higher portion than non-fishing vessels, but the occurring ratio of fishing vessel casualties were marked 2.96 times lower than that of non-fishing vessel casualties. The occurring ratios of bigger fishing vessel casualties were higher than smaller ones. Most marine casualties were resulted from the human factors such as poor watchkeeping, negligent action for engine and etc. The trend of marine casualties showed that the machinery damage hold the first and collision accidents took the second, but on a point of cause of them, operating errors took first and poor handling or inspection of machinery held the second place. Because those two casualties took major portion, and very important problems for safety of fishing vessels, so we ought to try to reduce the factors before everything else. In addition, since collision, sinking and capsizing in marine casualties have led to death, missing and injury of lives, it is necessary for navigation operators to take more educations and training intended to reduce the marine casualties systematically and continuously.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.53 no.2
• /
• pp.196-203
• /
• 2017

The renewable energy sources can be thought of one of the major measures to reduce greenhouse gas emissions in the industries. However, the utilization technology for those sources is approaching in the different matters. One of them, thermoelectric generation might be applicable to fishing industry. A various of internal combustion engines are used in a wide range of fisheries. After the ignition process, the heat passed out from the exhaust outlet. Recycling the heat could be not only an energy source but also reduction of green gas emission. Therefore, this study was designed to verify the feasibility of generation from wasted exhaust gas and analyze the performance. The designed experiment devices were connected with a data logger and an electric loader to quantify the currency and voltage. The devices were installed in a coastal fishing vessel for a gillnet fishery. During the whole fishing trips, the amount of generation was measured by engine rpm and the fishing operation procedures including vessel operations. At the maximum 1,500 rpm in the practical range, the generation amount was 113.6 W. The amount difference in relation to connection method was within 5 W: serial connection was 111.4 W and parallel connection was 115.8 W.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2006.05a
• /
• pp.61-65
• /
• 2006

A thery was developed to design a high pressure vessel with combined structure of the metal and the composite to withstand the pressure of several tens of thousands psias to reduce the weight of the impulse motor which produces high level of thrust within several tens of seconds. The elastic-plastic stress analyses were carried out to prove the validity of the design theory A combustion chamber of the impulse motor was designed by the design theory, fabricated, and tested by the hydraulic pressure and the static firings. The bursting pressures from the tests were compared to those predicted by tile design theory and the stress analyses and found to be almost the same. It will be possible to design the high pressure vessel with combined structure of the metal and the composite very easily by the proposed design theory.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.10 no.2
• /
• pp.23-30
• /
• 2006

A thery was developed to design a high pressure vessel with combined structure of the metal and the composite to withstand the pressure of several tens of thousands psias to reduce the weight of the impulse motor which produces high level of thrust within several tens of seconds. The elastic-plastic stress analyses were carried out to prove the validity of the design theory. A combustion chamber of the impulse motor was designed by the design theory, fabricated, and tested by the hydraulic pressure and the static firings. The bursting pressures from the tests were compared to those predicted by the design theory and the stress analyses and found to be almost the same. It will be possible to design the high pressure vessel with combined structure of the metal and the composite very easily by the proposed design theory.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.12 no.3
• /
• pp.125-130
• /
• 1979

In this paper, the noise pressure propagated in the air on account of the engine revolution of a stern trawler, Sae-Ba-Da(G. T. 2275.71) was measured at the check points No.1 through No.43 when the vessel was cruising, towing nets, and drifting. The experiment was carried out in the period from August 23 to October 22, 1978 at the locations of lat. $33^{\circ}$ 47'N, long. $127^{\circ}$ 34'E; lat. $34^{\circ}$ 24'N, long. $128^{\circ}$ 23'E; and lat. $6^{\circ}$ 01'N, long. $108^{\circ}$ 04'E. In case of cruising, noise on the weather deck came from funnel noise. The highest noise pressure was 92dB at observation point No.9 where tile noise pressure from main engine was 105dB when the engine was operated at 730rpm and $12^{\circ}$ sorely propeller pitch. The noise measured was reduced to 90dB at observation point No.9 when the screw propeller pitch was changed to $8^{\circ}$ that resulted in reduction of engine to 103dB. In case of towing net, the main engine revolution and screw propeller pitch was fixed at 730rpm and $8^{\circ}$ respectively. But the engine noise pressure was increased up to 106dB due to the towing resistance by 14 tons of the nets, and the noise pressure was 90dB at No.9 point. A hight noise was also generated from screw because of the towing reoistance and could be measurable even in the wall of the insulated freezing room. When the vessel was drifting: the noise pressure from the generator operated, at 720rpm was 100dB. This caused 87dB noise pressure at No.9 point. The noise pressure in the boarding or residence sections was 45 to 60dB in each case of cruisinrg towing net or drifting but it was so high as 82dB on the open deck that voice could hardly be heap.

• Journal of Advanced Marine Engineering and Technology
• /
• v.37 no.4
• /
• pp.332-337
• /
• 2013

National investment was performed in the research and development of renewable energy because of climate change by air pollution, exhaustion of energy sources, energy security, and so on. Biodiesel fuel of the renewable energy is highlighted as friendly environment energy, it is possible to operate in regular diesel engines when it is blended with invariable ratios without making any changes. Emission factors have been estimated for commercial ship from various research institutes; however, it is difficult to develop emission factors for military vessels. In this work, biodiesel blended fuel emission factors for sulfur dioxide and carbon dioxide were quantitatively estimated from propulsive diesel engine installed on naval vessel using fuel property analysis. In addition, exhaust emissions were quantitatively calculated on the basis of fuel consumption rate with biodiesel content by percentage.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.14 no.4
• /
• pp.260-264
• /
• 1981

The purpose of the present study is to measure the sound spectrum of the underwater noise generated by a stern trawler M/S Saebada (2,275 GT, 3600 ps) in the various operational conditions. Underwater noises were recorded by a hydrophone (B & K 8100) and analyses were made rising a digital frequency analyzer (B & K 2131) and level recorder (B & K 2370). The predominant frequency range was 100-500 Hz, and maximum sound pressure level was 121 dB(re. $1{\mu}Pa$). Underwater noise level increased with the increased speed of the vessel. Sound pressure level measured in the course of astern cruising was higher than that measured in the course of ahead cruising and also the noise spectrums were different in these two cases. At the time of cruising the underwater noise was higher than 10 dB compared to those values measured at the time at rest with only engine operation. The underwater noise of the vessel was mainly due to the main engine revolution of the propeller and the vibration of hull.