• Title/Summary/Keyword: Vessel engine

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Literature Review on Alternative Traditional Treatment of Spasmodic Torticollis - focusing on Chinese Traditional Medicine's Journals - (연축성 사경 치료에 관한 문헌적 고찰 - 중국 논문 중심으로 -)

  • Lee, Won Chul;Sun, Seung Ho
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.27 no.1
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    • pp.34-42
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    • 2013
  • Our study is to review Chinese traditional medicine's journals about the diagnosis and treatment of spasmodic torticollis such as category, syndrome differentiation, acupoints of treatment, and herbal medicine. The journal search was performed using the search engine of China Academic Journal (CAJ) and China Doctor/Master's Dissertation (CDMD) in China National Knowledge Infrastructure (CNKI) from January 1982 to October 2012. Searching key words were the diverse combination of "spasmodic torticollis", "cervical dystonia", "Chinese traditonal medicine", "herbal medicine", "acupuncture", and "syndrome differentiation". The inclusion criteria was all kinds of journals including Chinese traditional medicine approach except for experiment study. The category, syndrome differentiation, acupoints of treatment, and herbal medicine from finally selected journals were extracted and summarized. The fourty-seven Chinese journals were selected finally. The category was divided into wind syndrome, trembling syndrome, convulsive syndrome, and convulsions. The syndrome differentiation was classified as internal stirring of liver wind, yin-blood depletion, invasion of external contraction, uncontrol of governor vessel, internal obstruction of phlegm turbidity, dual deficiency of qi and blood, and blood stasis due to qi stagnation. The combination of acupoints to unblock the meridian and dissipate binds and to tonify governor vessel and repel tremor was mainly used in acupuncture treatment. Galgun-tang or galgun-tanggami was primarily used and the others were the prescriptions to tonify liver and kidney, to calm convulsion, and to dispeling wind-phlegm. We suggests that spasmodic torticollis could be treated using Korean medicine's approach in Korea.

A study on the analysis of bearing reaction forces and hull deflections affecting shaft alignment using strain gauges for a 50,000 DWT oil/chemical tanker (스트레인 게이지를 이용한 5만 DWT급 석유화학제품운반선의 베어링 반력 및 선체변형량 분석에 관한 연구)

  • Lee, Jae-Ung
    • Journal of Advanced Marine Engineering and Technology
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    • v.40 no.4
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    • pp.288-294
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    • 2016
  • In modern ships, the shafting system often becomes stiff owing to the high engine power, whereas the hull structure becomes more flexible owing to optimization using high-tensile-strength thick steel plates; therefore, more sophisticated shaft alignments are required. In this study, strain gauge-based measurement was conducted under five vessel operating conditions and bearing reaction forces and hull deflections affecting shaft alignment were analyzed for a 50,000 dead weight tonnage oil/chemical tanker that has gained repute as an eco-friendly vessel in recent years. Furthermore, the analytical results from each technique-theoretical calculation, jacking ups, and strain gauges-were cross-checked against each other in order to enhance the degree of accuracy and reliability of the calculation.

Comparison and Analysis of Fuel Consumption by CODAD, CODLOD and CODLAD System for Combat Support Ship (군수지원함의 CODAD, CODLOD 및 CODLAD 추진체계에 따른 연료 소비량 비교 및 분석)

  • Kim, Min-wook;Oh, Jin-seok
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.5
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    • pp.1049-1059
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    • 2017
  • After patrol corvett Cheonan was hit and sank on duty, the Republic of Korea Navy has tried to install hybrid propulsion system on naval ship to reduce vibration and noise problems during navigation. The hybrid propulsion system has advantage that propulsion motor can be propelled in low speed operation of the vessel. This can be a better quietness than a mechanical propulsion system which consists of a conventional internal combustion engines. And more economical operation is possible by using a propulsion motor in a low speed operation where a fuel efficiency of the internal combustion engine is poor. In this paper, we set up virtual ship on the basis of a combat support ship in the Republic of Korea Navy, economically compared and analyzed fuel consumption between conventional and hybrid propulsion system. As a result, it was confirmed that the fuel efficiency of hybrid propulsion system which use electric motor had been relatively improved.

Estimating the productive efficienct of distant-water longline vessels in Pacific Ocean using a Stochastic Frontier Approach (SFA를 이용한 태평양 원양연승어업의 어선별 생산효율성 분석)

  • CHO, Heon-Ju;KIM, Doo Nam;KIM, Do Hoon;LEE, Sung Il;KWON, Youjung;KU, Jeong Eun
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.53 no.4
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    • pp.357-362
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    • 2017
  • The purpose of this study is to analyze the efficiency of distant-water longline fishing vessels in the Pacific Ocean and the gap in efficiencies among individual vessels. In order to estimate the efficiency, the dependent variable is set as an amount of catch and independent variables include number of crew, number of hooks, number of vessel size, and vessels engine power associated with fishing activities of distant water longline fisheries. Analytical result was shown as follows: first, the average efficiency of distant-water longline fishing vessels in the Pacific Ocean was found to be 94%. Second, the number of hooks were found to be statistically significant in each input variable and the appropriate control of the number of hooks would be expected to have a positive effect on the efficiency. Third, the relationship between the age of a vessel and the efficiency was not found statistically.

Characteristics on the rolling response of a small fishing boat according to the waves and the ship's speed (파랑의 조우각과 선속 변화에 따른 어선의 횡동요 특성)

  • Kang, Il-Kwon;Kim, Hyung-Seok;Kim, Min-Seok;Lee, Yoo-Won;Kim, Jung-Chang;Jo, Hyo-Jae;Lee, Chun-Ki
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.43 no.1
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    • pp.62-70
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    • 2007
  • Marine casualties of vessel are serious problems on social and national aspects, because it results in sacrifice of lives, a great lose of properties and marine pollution. According to recent statistics of marine casualties of vessel, fishing boats are more likely to be ended in the casualty, and especially, small fishing boats cause much more accidents than any other big vessels. Most of marine casualties were caused by the human factors such as poor watch keeping, inadequate manoeuvering and negligent action for engine, etc. This study is intended to provide navigator of small fishing boat with a specific information of necessary to assist both the manoeuvering and the avoidance of capsizing. The manoeuvering characteristics of ship can be adequately judged by the results of typical ship trials manoeuvres. For this purpose, the author measured the roll responses of a small fishing boat in waves using the real sea experimental measuring system, and analyzed the experimental data by the statistical and spectral analyzing methods to get the characteristics of the roll motion responses of the small boat through the wave directions and the ship's speed.

A Study on the Hull Form Design and Ice Resistance & Propulsion Performance of a Platform Support Vessel (PSV) Operated in the Arctic Ocean (극지해역 운용 해양작업지원선(PSV)의 선형설계와 빙 저항추진 성능 연구)

  • Yum, Jong-Gil;Kang, Kuk-Jin;Jang, Jin-ho;Jeong, Seong-Yeob
    • Journal of the Society of Naval Architects of Korea
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    • v.55 no.6
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    • pp.497-504
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    • 2018
  • Platform Support Vessels operated in the Arctic Ocean support diverse operations of offshore plant in the sea, and the PSV is also needed to support works to exploit the oil and gas in the Arctic Ocean. Both of the ice breaking and the open sea performance have been considered together to secure the enhanced operational performance at the harsh environment in the Arctic Ocean and the open sea as well. In this study, One of the design requirements of a PSV is to guarantee continuous icebreaking performance with 3 knots at 1 m thickness of level ice, where the design draft is 7.5m and the engine power is 13 MW. Three hull forms were designed, and the ice resistance based on empirical formulas was estimated to select the initial hull form having an outstanding performance. The full scale performance of the designed hull forms was predicted by the ice model test conducted in the ice model basin of Korea Research Institute of Ships & Ocean Engineering(KRISO). The analysed results show that the selected hull form satisfies the above design requirement.

Study on Equivalent Consumption Minimization Strategy Application in PTI-PTO Mode of Diesel-Electric Hybrid Propulsion System for Ships

  • Lee, Dae-Hong;Kim, Jong-Su;Yoon, Kyoung-Kuk;Hur, Jae-Jung
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.3
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    • pp.451-458
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    • 2022
  • In Korea, five major ports have been designated as sulfur oxide emission control areas to reduce air pollutant emissions, in accordance with Article 10 of the "Special Act on Port Air Quality" and Article 32 of the "Ship Pollution Prevention Regulations". As regulations against vessel-originated air pollutants (such as PM, CO2, NOx, and SOx) have been strengthened, the Ministry of Oceans and Fisheries(MOF) enacted rules that newly built public ships should adopt eco-friendly propulsion systems. However, particularly in diesel-electric hybrid propulsion systems,the demand for precise control schemes continues to grow as the fuel saving rate significantly varies depending on the control strategy applied. The conventional Power Take In-Power Take Off(PTI - PTO) mode control adopts a rule-based strategy, but this strategy is applied only in the low-load range and PTI mode; thus, an additional method is required to determine the optimal fuel consumption point. The proposed control method is designed to optimize fuel consumption by applying the equivalent consumption minimization strategy(ECMS) to the PTI - PTO mode by considering the characteristics of the specific fuel oil consumption(SFOC) of the engine in a diesel-electric hybrid propulsion system. To apply this method, a specific fishing vessel model operating on the Korean coast was selected to simulate the load operation environment of the ship. In this study, a 10.2% reduction was achieved in the MATLAB/SimDrive and SimElectric simulation by comparing the fuel consumption and CO2 emissions of the ship to which the conventional rule-based strategy was applied and that to which the ECMS was applied.

Conceptual Design of the Fuel Injection Valve Tester for ME-LGI Marine Engine by Using System Engineering (ME-LGI 선박엔진용 연료분사밸브 테스터 개발을 위한 시스템 엔지니어링 기반 개념 설계)

  • Noh, Hyonjeong;Kang, Kwangu;Bae, Jaeil
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.5
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    • pp.681-688
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    • 2018
  • As environmental regulations have been strengthened and high fuel efficiency has been in demand in recent years, the number of ships using natural gas as a fuel is increasing. The demand for ships using LPG or methanol, which are emerging as eco-friendly vessel fuels, is also increasing. In this perspective, ME-LGI engines using LPG or methanol as a fuel have attracted considerable attention. Ships equipped with an ME-LGI engine are required to check the reliability of the fuel injection valve during shipping. This means that the development of a fuel injection valve tester is essential for the commercialization of ME-LGI engine. This study conducted the conceptual design of a fuel injection valve tester for ME-LGI engines using a system engineering process in the order of requirements analysis, functional analysis, and design synthesis. In the requirement analysis stage, the operating process of fuel injection valve was analyzed, and the necessity of checking the sealing oil leakage was then derived. In the functional analysis stage, the functions and flow of them were defined at each functional level. In the design synthesis stage, the equipment for each function was set and the process block diagram based on it was derived. In addition, preliminary risk analysis was performed as a part of system analysis and control, and safety measures were added to the conceptual design. This study is expected to be a good reference material for the concept design of other systems in the future because it shows the application process of a system engineering process to the conceptual design in detail.

Transient Torsional Vibration Response due to Ice Impact Torque Excitation on Marine Diesel Engine Propulsion Shafting (선박용 디젤엔진 추진축에서 빙 충격 토크 기진에 의한 과도 비틀림 진동 응답)

  • Barro, Ronald D.;Eom, Ki Tak;Lee, Don Chool
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.25 no.5
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    • pp.321-328
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    • 2015
  • In recent years, there has been an increasing demand to apply the new IACS(International Association of Classification Societies) standards for ice and polar-classed ships. For ice-class vessel propulsion system, the ice impact torque design criterion is defined as a periodic harmonic function in relation to the number of the propeller blades. However, irregular or transient ice impact torque is assumed to occur likely in actual circumstances rather than these periodic loadings. In this paper, the reliability and torsional vibration characteristics of a comparatively large six-cylinder marine diesel engine for propulsion shafting system was examined and reviewed in accordance with current regulations. In this particular, the transient ice impact torque and excessive vibratory torque originating from diesel engine were interpreted and the resonant points identified through theoretical analysis. Several floating ice impacts were carried out to evaluate torque responses using the calculation method of classification rule requirement. The Newmark method was used for the transient response analysis of the whole system.

The Study on the Analysis of Marine Accidents and Preventive Measures (해양사고의 분석과 방지대책에 관한 연구)

  • SEO, Man-Seok;BAE, Seok-Je
    • Journal of Fisheries and Marine Sciences Education
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    • v.14 no.2
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    • pp.149-160
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    • 2002
  • I have been analyzed the marine accidents during 10years(1992~2001) based on the maritime inquire court decision, the results were as follows: 1. The rate of accident occuring were showed fishing boat(69.9%), freighter(12.3%), tanker(4.3%), tug boat(3.8%), passenger boat(2.1%) by the usage. 2. The marine accident had been showed operational fault(67.3%), mishandling of engine equipment(21.7%), meteorological condition, etc(11%) by the reason, most accidents had been occured by the operator fault and rack of experience. 3. The marine accidents had been showed damage of hull and engine(27.5%), collision(24%), foundering(11.3%), fire(3.9%), agrounding(10%), by the kind of accidents. 4. The accidents had been occured (74.6%) at the coastal sea, harbour and (25.4%) at the open sea by the sectors. The accidents of the vessel less than 500ton were much increased (54.3%) also, The accidents were much occured at the time between 0400~0800 hours by the time.