• 제목/요약/키워드: Marine ship

검색결과 3,357건 처리시간 0.026초

한국동해의 바람응력 분포와 상층구조에 대한 적용 (Wind Stress Distribution and Its Application to the Upper-layer Structure in the East Sea of Korea)

  • 나정열
    • 한국해양학회지
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    • 제23권3호
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    • pp.97-109
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    • 1988
  • 한국 동해의 wind stress와 wind-stress curl의 값을 수산진흥원 정선관측 바람자료를 근거로 하여 계산하였다. 바람에 의한 해수 이용을 염두에 두고 주로 지속적이고 강한 바람을 취해서 구한 월평균 wind stress 값들은 동해 전체에서 구한 기존의 값들과 거의 같았으나 wind-stress curl의 경우는 그 값이 훨씬 크게 나타났다. 이는 동해가 국지적으로 지형적인 영향을 받은 것으로 판단된다. 한편 바람에 의한 상층수의 이동으로 울릉도 부근에는 계절에 관계없이 난수괴(warm core)가 존재 하나 그 위치는 고정되어 있지 않다.

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낚시 어선의 U형 어창을 이용한 횡요 감쇠에 관한 연구 (A study for rolling reduction of fishing boat by utilizing u-type fish-hold)

  • 최찬문;안장영
    • 수산해양기술연구
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    • 제44권2호
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    • pp.148-156
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    • 2008
  • In this study it will be discussed how to solve the problem of discomfort from rolling motion on the fishing boats. Most discomfort is caused by the short cycle of rolling due to the light weight of the boats. The light weight is due to the FRP material which dries a boat. A way to improve the feeling of boarding by using fish hold was researched. The experiment was done on experimental fishing boat made by FRP in Jeju. An existing fish hold was designed and manufactured through the rolling test and that was used for a marine experiment. The rolling condition of the U-tank boat ideally designed was compared to that of an existing fishing boat using the same conditions. The experiments were carried out two times on the stop engine in the outward Sehwa fishing port, which the experimental data had analysed for effects of rolling reduction to compare the U - tank with the of exiting fish hold. The results were confirmed that the U-boat tank in the roll period and GoM were more safe than the existing fish hold and the average amplitude and significant of rolling angles were decreased relatively.

Landsat TM 영상에 의한 원자력 발전소로부터의 온배수 확산의 추적조사 (A Tracing Survey of Hot Waste Spread from Nuclear Power Station by Means of Landsat TM Images)

  • 최승필;양인태
    • 한국측량학회지
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    • 제15권2호
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    • pp.231-236
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    • 1997
  • 지금까지는 선박등을 이용하여 표본추출등으로 온배수 확산관측이 이루어져 왔으나 온배수의 확산속도, 위상조건, 비용, 범위설정 및 위치결정등의 여러 방해인자등 때문에 동시성, 광역성 및 경제성등의 문제에 있어서 새로운 탐사방법이 요구되어 왔다. 그러나 인공위성 영상을 이용하여 분석하면 단시간에 해양환경을 감시 및 탐지할 수 있기 때문에 기존의 방법보다 상당히 신속하며 정확하게 수온분포와 확산정도를 감지할 수 있다 따라서 이 연구는 인공위성 영상에 의하여 수온의 조사, 온배수의 유동 및 확산상태등에 대하여 고찰하였다.

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인터넷 서비스 기반의 선체외판 가공 연구 (Curved Hull Plate Forming based on SOAP Internet Services)

  • 김찬석;손승혁;신종계;이필립
    • 대한조선학회논문집
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    • 제53권1호
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    • pp.69-75
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    • 2016
  • Fabrication of the hull plate demands a lot of man-hour and a high degree of technology. In recent years, commercial shipping orders have been fallen because of intensifying competition with low price of order and labor cost. In order to solve this problem, a countermeasure such as a cost reduction is required. In this study, we are dealing with the method of supplying the forming information of the hull to the production site. We reviewed studies of hull forming that have been proposed so far to develop a method for providing hull forming information. On the basis of given production plans from the production site of shipyard, we discuss how to convert shell plate to production plan. Then, we will discuss the efficiency of the distribution method through the network about the method of hull forming. Thus, we have modified the distribution method which was proposed before. Finally, we will introduce the enhanced method for providing fabrication information of the hull plate to the small and medium-sized shipyards.

워터젯 추진 고속선의 부가물이 침로안정성에 미치는 영향 (The Effect of Appendages of a Water-Jet Propelled High Speed Vessel on the Course Keeping Ability)

  • 박한솔;김동진;이성균;박종용;이기표
    • 대한조선학회논문집
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    • 제48권4호
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    • pp.357-362
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    • 2011
  • It has been often reported that a water-jet propelled high speed vessel lost the course keeping ability in seaway. In this study, model tests of a high speed vessel were performed to measure the running attitude and to check the course keeping ability. The model ship may lose the course keeping ability due to bad running attitudes such as bow drop. So model tests were carried out to improve the running attitude by changing the position of longitudinal center of gravity and using appendages at the bow and the stern of a model. The position of lateral center of pressure moved toward stern and the course keeping ability was improved by modifying the transom wedge angle.

선박용 디젤발전기의 진동 절연을 위한 설계 기준 (A Design Criterion for the Vibration Isolation of a Marine Diesel Generator Set)

  • ;;이돈출
    • 한국소음진동공학회논문집
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    • 제16권4호
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    • pp.329-338
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    • 2006
  • The resilient mounts of a diesel engine installed onboard a ship should be designed for both static and dynamic loads. If possible, the resonance frequencies of the six rigid body modes of the installation and the flexible modes of the engine support structure should not lie within the engine operation range. In this paper a design criterion is proposed to evaluate an isolation system which involves the summation of dynamic forces transmitted through the resilient mounts and elastic potential energy index stored in the mounts. A case study is also presented in which a diesel engine generator, which had an elastic foundation and was mounted in a 5500 TEU container vessel, was studied both theoretically and experimentally. The theoretical analysis of the test model was performed by using a single mass 6 degree of freedom system. Actual measurements of mechanical vibration of the engine and its foundation onboard were carried out, which showed the importance of including the flexibility of the engine support structure in the mode.

오징어 채낚기 낚시의 야광이 어획에 미치는 영향 (Influence of luminous jig to catching of squid jigging in the Korean waters)

  • 류경진;김형석
    • 수산해양기술연구
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    • 제55권4호
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    • pp.303-309
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    • 2019
  • This study identified the characteristics of squid jig in korea waters by investigating the effect of color and luminous performance of squid jig on the catch of squid and experimenting the result of jig according to green jig or white jig, and whether using luminous or not were tested in the sea to improve the jig of squid jigging. For this purpose, a total of 13 sea experiments were conducted using T/S No. 2 Galmaegi. As a result, 341 squids were caught. Among them, 221 squids were caught by green jig (64.8%), 64 squids were caught by white jig (18.8%), 41 squids were caught by green luminous jig (13.8%), and nine squids were caught by white luminous jig (2.6%). The green jig commonly used in jigging vessel was most effective, and luminous jig was less effective than that non-luminous jig. The squids caught were Japanese flying squid (Todarodes pacificus), swordtip squid (Loligo edulis) and spear squid (Loligo bleekeri), and no significant characteristics were found according to the color of jig and the presence of luminous.

선박용 디젤기관 크랭크 축계의 2절 비틀림 진동에 대한 연구 (A Study on the 2-node Torsional Vibration for Marine Diesel Engine Crankshaft)

  • 최문길;박건우
    • 대한조선학회 특별논문집
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    • 대한조선학회 2008년도 특별논문집
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    • pp.54-61
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    • 2008
  • With the development of computer program in calculation for torsional vibration of ship's propulsion shafting it has become possible to calculate all order's vibratory amplitude, vibratory torque, vibratory stress and synthesis value at all concerned revolutions by way of solving the vibratory equation directly. Though this kind of propulsion shafting vibration calculation method makes it possible to get generalized and precise result of calculation, the unexpected critical crankshaft torsional vibration has still appeared in maneuvering range of the engine. A close investigation has been carried out to find out the cause for the 2-node propulsion shafting torsional vibration of the crankshaft that exceeded the limitation value near the MCR 104rpm on the sea trial of the recently delivered 6000TEU class container vessel from HHIC. In conclusion, as the latest super-output engine with heavy crankshaft and propeller mass seems to be liable to 2-node torsional vibration of crankshaft, it is recommend that, in the design stage of propulsion shafting, its torsional vibration condition must be more carefully checked.

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The development of a practical pipe auto-routing system in a shipbuilding CAD environment using network optimization

  • Kim, Shin-Hyung;Ruy, Won-Sun;Jang, Beom Seon
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제5권3호
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    • pp.468-477
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    • 2013
  • An automatic pipe routing system is proposed and implemented. Generally, the pipe routing design as a part of the shipbuilding process requires a considerable number of man hours due to the complexity which comes from physical and operational constraints and the crucial influence on outfitting construction productivity. Therefore, the automation of pipe routing design operations and processes has always been one of the most important goals for improvements in shipbuilding design. The proposed system is applied to a pipe routing design in the engine room space of a commercial ship. The effectiveness of this system is verified as a reasonable form of support for pipe routing design jobs. The automatic routing result of this system can serve as a good basis model in the initial stages of pipe routing design, allowing the designer to reduce their design lead time significantly. As a result, the design productivity overall can be improved with this automatic pipe routing system.

선박추진축계 동특성 분석 프로그램 개발 (Development of Analysis Program of Dynamic Characteristic for the Propulsion Shafting System)

  • 하정민;이종명;이정훈;김용휘;안병현;최병근;김원철
    • 동력기계공학회지
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    • 제18권2호
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    • pp.57-61
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    • 2014
  • Due to the changes of marine transportation industry, it requires ship in larger scale and high speed. In order to operate efficiently, the engine should be work in high power and high horse power. The increase of the number of the propeller blades and the pitch of the screw and the weight, vibration of shafting problems occurs. To evaluate the safety of the system through analyzing the dynamic characteristics propulsion shafting system, was used to prove or to verify the Lalanne & Ferraris model validation.. It indicates that the Program through Campbell diagram and Critical speed map, Root rocus map, to ensure the reliability of the experimental model.