• Title/Summary/Keyword: Vessel

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A Study on the Application of Navigation Rule to a Towing Vessel and Her Tow, a Fishing Boat and a Vessel at Anchor. (어선ㆍ예인선단ㆍ정박선의 항법적용에 대한 소고)

  • 김인현
    • Journal of the Korean Institute of Navigation
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    • v.23 no.4
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    • pp.21-28
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    • 1999
  • In some cases a towing vessel and her tow, a fishing boat, and a vessel at anchor have a priority against a general power-driven vessel underway in the application of collision rule. This article aims at suggesting a practical guide for the construction of the meaning of a vessel engaging in fishing, a vessel engaged in towing operation such as severely restricts the towing vessel and her tow in their ability to deviate from their course and a vessel at anchor, which are permitted to have the above priority. The construction of the application of the collision rule on the above vessels is supported by the decisions of MAIA and the judgment of civil courts.

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Effects of Elastic Blood Vessel Motions on the Wall Shear Stresses for Pulsatile Flow of a Newtonian Fluid and Blood (뉴턴유체와 혈액의 맥동유동시 탄성혈관의 운동이 벽면전단응력분포에 미치는 영향)

  • Roh, Hyung-Woon;Kim, Jae-Soo;Park, Gil-Moon;Suh, Sang-Ho
    • Proceedings of the KSME Conference
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    • 2001.11b
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    • pp.318-323
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    • 2001
  • Characteristics of the pulsatile flow in a 3-dimensional elastic blood vessel are investigated to understand the blood flow phenomena in the human body arteries. In this study, a model for the elastic blood vessel is proposed. The finite volume prediction is used to analyse the pulsatile flow in the elastic blood vessel. Variations of the pressure, velocity and wall shear stress of the pulsatile flow in the elastic blood vessel are obtained. The magnitudes of the velocity waveforms in the elastic blood vessel model are larger than those in the rigid blood vessel model. The wall shear stresses on the elastic vessel vary with the blood vessel motions. Amplitude indices of the wall shear stress for blood in the elastic blood vessel are $4\sim5$ times larger than those of the Newtonian fluid. As the phase angle increased, point of the phase angle is are moved forward and the wall shear stresses are increased for blood and the Newtonian fluid.

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The Methodic Study on a Standard of Classification of Pulse Condition -a Focus of ${\ulcorner}$The Pulse Studies of Bin-Ho(瀕湖脈學)${\lrcorner}$- (맥상 분류 기준에 대한 방법론적 고찰 - "빈호맥학(瀕湖脈學)"을 중심으로 -)

  • Lee, Ju-Ho;Choi, Hwan-Soo;Kim, Chul-Jung
    • Korean Journal of Oriental Medicine
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    • v.10 no.1
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    • pp.49-61
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    • 2004
  • The Standardization of terms in The Pulse studies(脈學) is a need for development of learning. This study, for the correction of existing misused terms in The Pulse studies, we study on modernly and objectively the terms in The Pulse studies. By a focus of ${\ulcorner}$The Pulse Studies of Bin-Ho(瀕湖脈學)${\lrcorner}$, we studies on the new classification of pulse condition. The error of a existing technical books on Pulse studies begin that the classification of pulse condition is not establish a Standardization. For the correction of existing misused terms in The Pulse studies, we study on the pulse condition is expressed objectively a blood vessel that it is a subject of pulse condition. The expression of blood vessel contain a depth of blood vessel, a speed of pulsation, a curve of blood vessel, thickness of blood vessel, a diameter of blood vessel in expand and contract of blood vessel, a interval in expand and contract of blood vessel, a distinctness on a boundary of blood vessel, a speed of blood flow in blood vessel, a volume of blood flow in blood vessel, a condition of blood in blood vessel, a propelling power of blood vessel. These is standard of the new classification of pulse condition.

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CORIUM BEHAVIOR IN THE LOWER PLENUM OF THE REACTOR VESSEL UNDER IVR-ERVC CONDITION: TECHNICAL ISSUES

  • Park, Rae-Joon;Kang, Kyoung-Ho;Hong, Seong-Wan;Kim, Sang-Baik;Song, Jin-Ho
    • Nuclear Engineering and Technology
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    • v.44 no.3
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    • pp.237-248
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    • 2012
  • Corium behavior in the lower plenum of the reactor vessel during a severe accident is very important, as this affects a failure mechanism of the lower head vessel and a thermal load to the outer reactor vessel under the IVR-ERVC (In-Vessel corium Retention through External Reactor Vessel Cooling) condition. This paper discusses the state of the art and technical issues on corium behavior in the lower plenum, such as initial corium pool formation characteristics and its transient behavior, natural convection heat transfer in various geometries, natural convection heat transfer with a phase change of melting and solidification, and corium interaction with a lower head vessel including penetrations of the ICI (In-Core Instrumentation) nozzle are discussed. It is recommended that more detailed analysis and experiments are necessary to solve the uncertainties of corium behavior in the lower plenum of the reactor vessel.

Study on the Design, Manufacture, and Pressure Test of a Pressure Vessel Model (내압용기 모형의 설계, 제작 및 압력시험에 관한 연구)

  • Joung, Tae-Hwan;Lee, Jae-Hwan;Lee, Chong-Moo;Hykudome, Tadahiro;Sammut, Karl;Nho, In-Sik
    • Journal of Ocean Engineering and Technology
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    • v.21 no.6
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    • pp.101-106
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    • 2007
  • In this paper, the authors demonstrate a new idea to take the place of the real pressure vessel test, which should be carried out in a high pressure experiment unit before the real sea trial test. The idea is to make a pressure vessel model as a replica of the real pressure vessel test, which can reduce the cost of making a pressure vessel and large pressure experiment unit. The pressure vessel model was designedbased on linear-elastic, buckling equations and Finite Element Analysis. The manufactured pressure vessel model was investigated and monitored while the pressure test was being conducted. After the test, the result and the validity of the pressure vessel model as a replica of the real pressure vessel test was studied.

Comparative Anatomy of Diffuse-Porous Woods Grown in Korea (I) -Characteristics by Simple Correlation and Principal Component Analysis- (한국산(韓國産) 산공재(散孔材)의 해부학적(解剖學的) 특성(特性)에 관한 비교연구(比較硏究)(I) -단순상관(單純相關)과 주성분(主成分) 분석(分析)에 의한 특성(特性)-)

  • Chung, Youn-Jib;Lee, Phil-Woo
    • Journal of the Korean Wood Science and Technology
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    • v.23 no.4
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    • pp.46-53
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    • 1995
  • The anatomy of Korean diffuse-porous woods, 36 families, 75 genera, 145 species, 215 specimens was described and analyzed. Sixteen wood anatomical characters, habit and phenology factors were determined by simple correlation and principal component analysis. Strong positive correlations were found between vessel element length and fiber length, ray width and ray height, simple pits of fiber wall and paratracheal parenchyma distribution. The results of principal component analysis (PCA) disclose the primitive characteristics and the direction of xylem evolution of Korean diffuse-porous woods. The xylem evolution scenario for Korean dicotyledonous woods is considered to be developed in the direction of decreasing trends of vessel frequency, vessel element length, and length/diameter(L/D) ratio of vessel element but increasing trends of vessel diameter, fiber length/vessel element length(F/V) ratio, libriform wood fibers, simple perforation, and homogeneous ray composition. Increase of vessel diameter and decrease of vessel frequency seem to be related to the improvement of conductive efficiency, and increase of the vessel element length and occurrence of scalariform perforation in vessel element may be related to enhanced of conductive safety. Also the libriform wood fibers and ray features appear to have relationship with mechanical support and nutrient metabolism, respectively.

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Effects of vessel-pipe coupled dynamics on the discharged CO2 behavior for CO2 sequestration

  • Bakti, Farid P.;Kim, Moo-Hyun
    • Ocean Systems Engineering
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    • v.10 no.3
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    • pp.317-332
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    • 2020
  • This study examines the behaviors and properties of discharged liquid CO2 from a long elastic pipe moving with a vessel for the oceanic CO2 sequestration by considering pipe dynamics and vessel motions. The coupled vessel-pipe dynamic analysis for a typical configuration is done in the frequency and time domain using the ORCAFLEX program. The system's characteristics, such as vessel RAOs and pipe-axial-velocity transfer function, are identified by applying a broadband white noise wave spectrum to the vessel-pipe dynamic system. The frequency shift of the vessel's RAO due to the encounter-frequency effect is also investigated through the system identification method. Additionally, the time histories of the tip-of-pipe velocities, along with the corresponding discharged droplet size and Weber numbers, are generated for two different sea states. The comparison between the stiff non-oscillating pipe with the flexible oscillating pipe shows the effect of the vessel and pipe dynamics to the discharged CO2 droplet size and Weber number. The pipe's axial-mode resonance is the leading cause of the fluctuation of the discharged CO2 properties. The significant variation of the discharged CO2 properties observed in this study shows the importance of considering the vessel-pipe motions when designing oceanic CO2 sequestration strategy, including suitable sequestration locations, discharge rate, towing speed, and sea states.

Unscented Kalman Snake for 3D Vessel Tracking

  • Lee, Sang-Hoon;Lee, Sanghoon
    • Journal of International Society for Simulation Surgery
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    • v.2 no.1
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    • pp.17-25
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    • 2015
  • Purpose In this paper, we propose a robust 3D vessel tracking algorithm by utilizing an active contour model and unscented Kalman filter which are the two representative algorithms on segmentation and tracking. Materials and Methods The proposed algorithm firstly accepts user input to produce an initial estimate of vessel boundary segmentation. On each Computed Tomography Angiography (CTA) slice, the active contour is applied to segment the vessel boundary. After that, the estimation process of the unscented Kalman filter is applied to track the vessel boundary of the current slice to estimate the inter-slice vessel position translation and shape deformation. Finally both active contour and unscented Kalman filter are inter-operated for vessel segmentation of the next slice. Results The arbitrarily shaped blood vessel boundary on each slice is segmented by using the active contour model, and the Kalman filter is employed to track the translation and shape deformation between CTA slices. The proposed algorithm is applied to the 3D visualization of chest CTA images using graphics hardware. Conclusion Through this algorithm, more opportunities, giving quick and brief diagnosis, could be provided for the radiologist before detailed diagnosis using 2D CTA slices, Also, for the surgeon, the algorithm could be used for surgical planning, simulation, navigation and rehearsal, and is expected to be applied to highly valuable applications for more accurate 3D vessel tracking and rendering.

Enhancement of Downward-Facing Saturated Boiling Heat Transfer by the Cold Spray Technique

  • Sohag, Faruk A.;Beck, Faith R.;Mohanta, Lokanath;Cheung, Fan-Bill;Segall, Albert E.;Eden, Timothy J.;Potter, John K.
    • Nuclear Engineering and Technology
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    • v.49 no.1
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    • pp.124-133
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    • 2017
  • In-vessel retention by passive external reactor vessel cooling under severe accident conditions is a viable approach for retention of radioactive core melt within the reactor vessel. In this study, a new and versatile coating technique known as "cold spray" that can readily be applied to operating and advanced reactors was developed to form a microporous coating on the outer surface of a simulated reactor lower head. Quenching experiments were performed under simulated in-vessel retention by passive external reactor vessel cooling conditions using test vessels with and without cold spray coatings. Quantitative measurements show that for all angular locations on the vessel outer surface, the local critical heat flux (CHF) values for the coated vessel were consistently higher than the corresponding CHF values for the bare vessel. However, it was also observed for both coated and uncoated surfaces that the local rate of boiling and local CHF limit vary appreciably along the outer surface of the test vessel. Nonetheless, results of this intriguing study clearly show that the use of cold spray coatings could enhance the local CHF limit for downward-facing boiling by > 88%.