• Title/Summary/Keyword: harbour

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Practicality of Woo's Super Rudder Controlling (우즈 수퍼러더조선법의 실용성에 관하여)

  • 우병구
    • Journal of the Korean Institute of Navigation
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    • v.17 no.3
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    • pp.69-76
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    • 1993
  • In harbour the practical shiphandlers should have a expert knowledge of systematically reducing head-way and keeping ship's positions to the final position with confidence and under control. But now in the practical approaches we do not have any special maneuvers of controlling the ship effi-ciently regarding the headway and approaches except some existing reduction of speeds according to the Weight-to-Power Ratio, use of astern power and Rudder Cycling. Consequently this study put Woo's Super Rudder Controlling originally developed by Captain Woo, Ph. D. to practical use as a special maneuvers in the port approaches. The conclusions of this paper are drawn as follows : 1) Optimum standard and desirable controls in combination of three engine speeds with three yaw ang-les were proposed for the practical shiphandlers, 2) According to simulation of the pilotships the Super advances are 10.5 ship lengths for Full full full maneuvers, and 7.9 ship lengths for Full half maneuvers approximately, 3) Approach maneuvers to anchorages by trying Woo's Super Rudder Controlling saved about 30% of total standby time in comparison with the existing Weight-to-Power Ratio maneuvers in the Pusan and Kwang Yang ports.

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Crabbing Test of a 3m Ferry Model (II) (3m Ferry 모형선의 Crabbing 시험(II))

  • SHIN HYUN KYOUNG;LEE HYUNG LAK
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2004.05a
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    • pp.290-297
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    • 2004
  • In this paper, one of the harbour maneuvering tests is described. Its goal is to investigate the so-called crabbing performance of ships. By crabbing is meant the ability of the vessel to move sideways with the use of her own maneuvering devices like propellers, rudders, transverse thruster, etc. the 3m ferry model is made by ocean engineering wide tank in the university of ulsan. when the model ship is leaving and going to the quay, Transverse forces and Yawing moments are measured, in the condition of zero longitudinal force and the design draught, by load cell attached to the longitudinal center of gravity on the ship. the purpose of the experiment is to verify the reliability of ocean wide tank in university of ulsan about crabbing test compared with results of foreign research institute.

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Consideration on the Risk of Corrosion Assessment in Reinforced Concrete Structure by Corrosion Potential Criterion (부식전위 기준에 의한 철근콘크리트 구조물의 부식진단의 위험성에 관한 고찰)

  • Jeong, Jin-A
    • Corrosion Science and Technology
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    • v.14 no.3
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    • pp.147-152
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    • 2015
  • Corrosion of steel reinforcement is a major factor in the deterioration of harbour and bridge structure. Steel corrosion in concrete must be checked for assessing the condition of a reinforced concrete structure. There are several ways how to measure the corrosion condition of reinforced concrete, but the corrosion potential measurement is a very simple, rapid, cost-effective and non-destructive technique to evaluate the severity of corrosion in reinforced concrete structure, therefore commonly used by engineers. However some particular situations may not relate to the reinforcement corrosion probability and a simple comparison of the corrosion potential data with the ASTM C876 Standard on steel reinforcement corrosion probability could be meaningless and not give reliable informations because of environment factors as oxygen concentration, chloride content, concrete resistance. Therefore this paper explains the risk of corrosion assessment in reinforced concrete structure and how many factors can affect the reliability of the corrosion potential data.

Experiments Research for Steel Corrosion of Reinforced Concrete Specimens in the Splash Zone (비말대 거치 철근콘크리트 시험체의 철근부식에 관한 연구)

  • 이상국;류금성;정영수;유환구;김국한
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.10a
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    • pp.755-758
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    • 1999
  • Reinforced concrete is in general known as high durability construction material under normal environments due to strong alkalinity of cement. Marine and harbour concrete in the tidal and the splash zone at seashore are exposed to cyclic wet and dry saltwaters which cause to accelerate corrosion of reinforcing steel in concrete. If corrosion resistance of concrete gets to weaken due to carbonations and cracks in cover concrete, furthermore, concrete durability rapidly decreases by corrosion of reinforcement steel embedded in concrete. The objective of this study is to develop appropriate corrosion protection systems so as to enhance the durability of concrete by controlling the cover depth of concrete and by using corrosion inhibitors as concrete admixtures.

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A Study on the Men′s Underclothes of Baroque Age (바로크 시대의 남성 속옷에 관한 고찰)

  • 김주애
    • The Research Journal of the Costume Culture
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    • v.6 no.4
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    • pp.203-212
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    • 1998
  • During the Baroque Ages, the underclothes of both sexs developed a new significance. They ceased altogether to be merely utilitarian in function, and were exploited, to a striking degree, to indicate class distinction and sex attraction. Up to this period, as e have seen, the underclothes of men and women had very much the same significance, but from now on there is a division. The male garments are designed mainly to express social rank, the female mainly to attract. The man's shirt is an integral part of the visible costume of the find gentleman. After 1660, The fashion portrayed by the men, exhibiting the shirt extruding between the bottom of the waistcoat and the top of the breeches is still more remarkable and significant. The period is important in that it was the last time that the male attempted to give his under clothing an erotic suggestion. It was their experience that silk and linen garments next to the skin were less liable than wool to harbour lice. Until the era of physical cleanliness opened a century later, woollen undergarments were rarely worn. the nineteenth century accepted cleanliness as a sign of class distinction.

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A Study on the Establishment of Oil Spill Response Measures in Yeosu Waters (여수해역에 있어서 기름유출에 대한 방제대책 수립에 관한 연구)

  • 국승기;윤종휘;김원돈;이상호
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.7 no.2
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    • pp.23-37
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    • 2001
  • Marine environment has been polluted and damaged by many sources such as industrial waste, natural seepage, oil spill and offshore production etc. Among them, oil spill from oil tankers is one of most harmful sources to marine lives as its input amount is huge at a limited area for short period. In Korea, the port of Yeosu is known to be very vulnerable to oil spill with large amount of petroleum transported across the harbour. In this regards, the author analyzed and reviewed marine environment and appropriate response to marine oil spill at this area. For these purposes, oceanographic and meteorologic features as well as regional characteristics of harbor facilities, shipping routes, marine traffic and fisheries were investigated, also traffic densities were analyzed in order to check marine accident probabilities making direct observations for 72 hours visual1y and by portable radar.

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Applications and Key Technologies of Biomimetic Underwater Robot for Naval Operations (생체모방형 수중로봇의 해양작전 운용개념 및 핵심소요기술)

  • Lee, Ki-Young
    • Journal of the Korea Institute of Military Science and Technology
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    • v.18 no.2
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    • pp.189-200
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    • 2015
  • This paper gives an overview on the some potential applications and key technologies of biomimetic underwater robot for naval operations. Unlike most manned underwater naval systems, biomimetic underwater robots can be especially useful in near-land or harbour areas due to their ability to operate in shallow water effectively. Biomimetic underwater robot provide advantages in reaching locations that would be difficult or too dangerous for a manned vehicle to reach, as well as providing a level of autonomy that can remove the requirement for dedicated human operator support. Using multiple or schools of underwater robots would provide increased flexibility for navigation, communication and surveillance ability. And it alleviate some of the restrictions associated with speed and endurance design constraints.

A Practical Study on Aids to Navigation (항로표지에 관한 실무적 고찰)

  • Yoon, Byoung-Won
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2007.12a
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    • pp.365-372
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    • 2007
  • The function of navigational aids are to be coincided with the development of navigational equipment and increase of traffics on the sea fairway. Supplementary function or side effect of wharf-edge illumination would be effective to indicate fairway indirectly and collision avoidance between ships and bridge against background light in port area at night also a serious-view light on the bridge posts would be effective to ensure the drifting ships by wind and current force adjacent bridge area.

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A Study on Avoiding Collision between a Ship and Bridge and Minimizing Damages if Unavoidable (선박과 교량의 충돌예방과 충돌시 손상의 감소방법에 관한 연구)

  • Yoon, Byoung-Won;Yun, Jeom-Dong
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2007.12a
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    • pp.376-382
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    • 2007
  • A Collapse of bridge by ship's collision to the bridge post may lead a great calamity. This paper investigates on avoiding collision between a ship and bridge by improvement of environmental factors, submitting a counter plan of reducing collision effect by triangular type of collision protecting bar and ship maneuvering skills. Putting up collision protecting bar fences of triangular type around the bridge posts would decrease the collision impact force by 75 percent.

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Stem Cells in Drug Screening for Neurodegenerative Disease

  • Kim, Hyun-Jung;Jin, Chang-Yun
    • The Korean Journal of Physiology and Pharmacology
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    • v.16 no.1
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    • pp.1-9
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    • 2012
  • Because the average human life span has recently increased, the number of patients who are diagnosed with neurodegenerative diseases has escalated. Recent advances in stem cell research have given us access to unlimited numbers of multi-potent or pluripotent cells for screening for new drugs for neurodegenerative diseases. Neural stem cells (NSCs) are a good model with which to screen effective drugs that increase neurogenesis. Recent technologies for human embryonic stem cells (ESCs) or induced pluripotent stem cells (iPSCs) can provide human cells that harbour specific neurodegenerative disease. This article discusses the use of NSCs, ESCs and iPSCs for neurodegenerative drug screening and toxicity evaluation. In addition, we introduce drugs or natural products that are recently identified to affect the stem cell fate to generate neurons or glia.