• Title/Summary/Keyword: Small Vessels

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Morphological studies on hemal nodes and hemolymph nodes in the water deer(Hydropotes inermis) (고라니 혈절과 혈림프절에 관한 형태학적 연구)

  • Yoon, Yeo-sung;Lee, Joon-sup
    • Korean Journal of Veterinary Research
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    • v.37 no.3
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    • pp.463-469
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    • 1997
  • This study was performed to investigate the gross anatomical features and microscopical structures of the hemal nodes and the hemolymph nodes in the water deer (Hydropotes inermis) found in Kangwon-do, Korea. The hemal nodes and hemolymph nodes were observed mainly in the periphery of the thoracic and abdominal aortae of the animals. The size of hemal nodes was generally smaller than that of the hemolymph nodes, and the shape of the both organs was spherical or ovoid. The color of the hemal nodes was red or black while that of the hemolymph nodes was gray with red bands. The hemal nodes were surrounded by a thin connective tissue capsule and there were extensive subcapsular and deep sinuses distended by a great number of erythrocytes. Although a few number of lymphatic nodules and small areas of diffuse lymphatic tissues were observed in the parenchyma, no typical cortex and medulla were defined in the hemal node. Small numbers of blood vessels were found at the connective tissue capsule but lymph vessel was not observed microscopically in this organ. The hemolymph nodes were covered by a relatively thick connective tissue capsule and there was a hilus in each node. The parenchyma was divided into cortex and medulla. The cortex was composed of a few numbers of lymphatic nodules and some diffuse lymphatic tissues. The medulla comprised medullary sinus and cords. Afferent and efferent lymph vessels were observed at the periphery of the capsule and the hilus, respectively. The subcapsular and medullary sinuses were not extensive but filled with small numbers of erythrocytes. The stroma of hemal node and hemolymph node was composed of reticular cells and fibers, and the capsule and trabecula consisted of collagenous fibers with smooth muscle fibers.

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Development and Feasibility Study for Phase Contrast MR Angiography at Low Tesla Open-MRI System (저자장 자기공명영상 시스템에서의 위상대조도 혈관조영기법의 개발과 그 유용성에 대한 연구)

  • Lee, Dong-Hoon;Hong, Cheol-Pyo;Lee, Man-Woo;Han, Bong-Soo
    • Progress in Medical Physics
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    • v.23 no.3
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    • pp.177-187
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    • 2012
  • Magnetic resonance angiography (MRA) techniques are widely used in diagnosis of vascular disorders such as hemadostenosis and aneurism. Especially, phase contrast (PC) MRA technique, which is a typical non contrast-enhanced MRA technique, provides not only the anatomy of blood vessels but also flow velocity. In this study, we developed the 2- and 3-dimensional PC MRA pulse sequences for a low magnetic field MRI system. Vessel images were acquired using 2D and 3D PC MRA and the velocities of the blood flow were measured in the superior sagittal sinus, straight sinus and the confluence of the two. The 2D PC MRA provided the good quality of vascular images for large vessels but the poor quality for small ones. Although 3D PC MRA gave more improved visualization of small vessels than 2D PC MRA, the image quality was not enough to be used for diagnosis of the small vessels due to the low SNR and field homogeneity of the low field MRI system. The measured blood velocities were $25.46{\pm}0.73cm/sec$, $24.02{\pm}0.34cm/sec$ and $26.15{\pm}1.50cm/sec$ in the superior sagittal sinus, straight sinus and the confluence of the two, respectively, which showed good agreement with the previous experimental values. Thus, the developed PC MRA technique for low field MRI system is expected to provide the useful velocity information to diagnose the large brain vessels.

Development of hull form of small and medium size coastal ships (연안항로용 중소형 섭박의 선형 개발)

  • 조용진;고창두;김성환
    • Journal of Ocean Engineering and Technology
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    • v.11 no.2
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    • pp.131-137
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    • 1997
  • The technology of small and medium sized shipbuilding companies is lower relatively to major shipbuilding companies, and should be up-graded from the viewpoint of national economic development. In spite that hul form design is one of the most important elements with respect to shipbuilding technology, small and medium sized shipbuilding companies are incapable of developing hull form. Inorder to support technically such companies hull form development was carried out for G/T 999ton class tanker and D/W 4990ton class tanker which are the typical vessels operating in coastal area. The operating efficiency for the developed hull forms are impeoved by 30% for G/T 999ton class tanker and 24% for D/W 4990 tonclass tanker respectively. The results of hull form development including ship model test and performance analysis are presented in this paper.

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A Study on the Classification Type Approval Certificate of Cruise Ship Equipment (크루즈선박 기자재의 선급형식승인에 관한 검토)

  • Kim, Ki-Pyoung;Kang, Ho-Keun;MA, Suk-In
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2011.06a
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    • pp.250-253
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    • 2011
  • The cruise industry is one of the world's fastest growing device industry which is structural construction coasts are expensive. Cruise out-fittings are thirty times compare with general large vessels. According to the characteristics of materials or equipments, most equipments are imported from europe. At present domestic shipbuilding industries and minor enterprises have a hard times therefore enhancing technology for the cruise industry could be infused vitality on the industries. If domestic small and midium industries have high technology for the cruise ship, domestic small and midium industries can have global competitiveness compare with european equipment suppliers which has small-scale and high technology. Therefore on this study, cruise ship's new equipment development and a study for the performance assessment and classification type approval certificate was carried out.

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A Study on the Exhaust Gas After Treatment for Small Ship (소형선박용 배기가스 후처리장치에 관한 연구)

  • Yi, Chung-Seob;Lee, Chi-Woo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.16 no.3
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    • pp.76-81
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    • 2017
  • In this research, to cope with the exhaust being reviewed to establish legal regulations for domestic small vessels, a basic experiment on an exhaust emissions post-treatment system was conducted to construct the design data required for securing a localized technology. The data was secured based on the arithmetic mean calculated through setting the engine load to 25%, 50%, and 75% and conducting five. A 2800-cc turbo charger diesel-type engine was used in the experiment, and an engine dynamometer was used in the conducted tests. As a result, NOx was reduced by approximately 20% and PM was reduced by approximately 97%. Although the results indicated no significant changes to CO in test mode-1, it was greatly reduced as it transitioned into the next phase.

A Study on s-INS for Small and Medium-Sized Ships

  • Park, Nam-Kyu;Kim, Joo-Young;Kim, Woo-Chul
    • Journal of information and communication convergence engineering
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    • v.5 no.3
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    • pp.289-294
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    • 2007
  • With regard to a marine safety system, large vessels are generally loaded with INS (Integrated Navigation System). But although small and medium-sized ships are exposed to safety accidents in the sea, they are not carrying proper navigation devices and equipment. Accordingly, in order to develop INS for small and medium-sized ships(s-INS), an existing INS has newly been organized and integrated. Recently, more strict enforcement of INS-related regulations is expected at home and abroad, and the scope of their applications is being broadened. To keep up with this global trend that ships are being loaded with digital devices and equipment, this study has tried to develop s-INS, broadening its applications, and suggesting a future research plan.

Structural Safety Evaluation of Hydraulic Steering System for Ship (선박용 유압 조타 시스템의 구조적 안전성 평가)

  • Lee, Moonhee;Son, Insoo;Yang, Changgun
    • Journal of the Korean Society of Industry Convergence
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    • v.23 no.4_2
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    • pp.661-667
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    • 2020
  • The optimal shape modeling of core parts through 3D modeling and structural analysis for the development of small and medium-sized ships. The goal is to improve the efficient structure of the hydraulic system for controlling the rudder among the core steering parts in small and medium-sized ships. Through 3D modeling and structural analysis, a new concept of tiller parts and a double-acting hydraulic cylinder control system were proposed and operational structural stability was evaluated. Structural analysis of the three different tiller designs that can be replaceable onto existing fishing vessels was conducted to derive the final shapes. The emphasis was placed on evaluating the structural stability of the key drive components, the tiller, pin, and cylinder rodin the maximum torque condition of the hydraulic cylinder.

A Flow Analysis of Small Craft by Using CFD

  • Park, Ji-Yong;Jeong, Jin-Hee;Hwang, Tea-Wook;Lee, Sol-Ah;Kim, Kyung-Sung
    • Journal of Multimedia Information System
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    • v.7 no.4
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    • pp.269-276
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    • 2020
  • The small craft including jet-board for leisure are commonly smaller than the general commercial vessels. For the floating vessel, the motion analysis is significantly important component to design the shape. It is, however, hardly predicting its behavior by using conventional boundary element method due to violating small amplitude assumption for potential theory. The computational fluid dynamics method can afford to simulate such small craft, but its grid system was not able to calculate motion, because movable body disturbs the grid system by confliction. The dynamics fluid body interaction model with over-set mesh system can be dealt with movable floating body under irregular ocean wave. In this study, several cases were considered to reveal that DFBI is essential method to predict floating body motion. The single phase simulate was conducted to establish the shape perfection, and then the validated vessel was simulated with ocean waves weather DFBI option on or off. Through the comparison, the results between the cases of DFBI on and off shows significantly difference. It was claimed that the DFBI was necessary not only to calculation body motion, but also to predict accurate drag and lift force on the floating body for small size craft.

A Study on the Traffic Stream and Navigational Characteristics at the Adjacent Sea Area of Busan Central Wharf (부산 중앙부두 주변해역의 교통흐름 및 통항특성에 관한 연구)

  • Kim Se-Won;Lee Yun-Sok;Park Young-Soo;Kim Jong-Sung;Yun Gwi-Ho;Kim Dae-Hee
    • Journal of Navigation and Port Research
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    • v.30 no.1 s.107
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    • pp.9-15
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    • 2006
  • At the adjacent sea area of Busan Central Wharf, a variety of vessels, such as middle-large passenger ships, small hugh speed crafts, container ships, cargo ships and working boats as well as small miscellaneous vessels are freely sailing comparatively without special rules and marine traffic control. In this research, we analyzed traffic stream and navigational characteristics cf main traffic route based on statistics and distribution of tracks by ship's type and tonnage cf the passing vessels after conducting marine traffic survey twice using exclusive software. We examined the traffic safety of the passing vessels by classifying the sea area by each function based on the analysis about this traffic situation, and analyzing the effect by designating 'Inner passage'. We also studied the plan for the effective rearrangement cf Central Wharf considering basically the traffic safety of arrival and departure in a point of view of navigators.

A Study on the Traffic Stream and Navigational Characteristics at the Adjacent Sea Area of Busan Central Wharf (부산 중앙부두 주변 해역의 교통 흐름 및 통항 특성에 관한 연구)

  • Kim Se-Won;Lee Yun-Sok;Park Young-Soo;Kim Jong-Sung;Yun Gwi-Ho;Kim Dae-Hee
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2005.10a
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    • pp.103-109
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    • 2005
  • At the adjacent sea area of Busan Central Wharf, a variety of vessels, such as middle-large passenger ships, small fast sailing ships, container ships, cargo ships and working ships as well as small miscellaneous vessels are freely sailing comparatively without special steering and sailing Rules and marine traffic control because exclusive wharfs in accord with their purpose and use have been arranged in each wharf. In this research, we analyzed traffic stream and navigational characteristics of main traffic route based on statistics and distribution of tracks by ship's type and tonnage of the passing vessels after conducting marine traffic survey twice using exclusive software by targeting the sea area during the period of time. We examined the traffic safety of the passing vessels by classifying the sea area by each function based on the analysis about this traffic situation, and analyzing the effect by designating 'Buknea passage'. We also studied the plan for the effective rearrangement of Central Wharf considering basically the traffic safety oif arrival and departure in a point if view of navigators.

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