• Title/Summary/Keyword: Small Vessels

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Reduction in Seismic Response of URANUS Liquid Metal Reactor by Using Three-Dimensional Seismic Isolator (3차원 면진장치를 이용한 URANUS 액체금속로의 지진응답감소)

  • Lee, Kuk-Hee;Kim, Yun-Jae;Ryu, Kang-Mook;Hwang, Il Soon;Yoo, Bong
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.7 no.3
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    • pp.30-39
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    • 2011
  • URANUS (Ubiquitous, Robust, Accident-forgiving, Non-proliferating, Ultra-lasting and Sustainer) has been developed with 35MWe (100MWth) operating without primary coolant pump, capitalizing on natural circulation capability of lead-bismuth eutectic (LBE) for long-life small and robust power units. To ensure the structural integrity, the large safety margin against Safe Shutdown Earthquake, 0.3g, and furthermore the cost effectiveness for URANUS, three-dimensional seismic base isolation design has been developed. The analytical model has been developed and seismic time history analyses have been carried out. The advantage for using three-dimensional seismic base isolation for URANUS has been discussed.

Anatomical Features of Agarwoods' Xylem (침향(沈香)의 목부조직(木部組織))

  • Park, Sang-Jin;Kim, In-Rak
    • The Korea Journal of Herbology
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    • v.20 no.3
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    • pp.9-18
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    • 2005
  • Objectives : The purpose of this study is to investigate characteristics of cell morphology of two different agar woods (Aquilaria agallocha Roxburgh (AAR) and imitative agar wood (IAW)) using microscopic techniques. Methods : Both light and scanning electron microscopes were used to observe morphological and histological features of the cell of agar woods collected from commercial products in the market. Results : The cell morphology and tissue arrangements of AAR depending on either the adsorption of resin into vessels or no adsorption of resin were observed to compare these features with those of both IAW and Aquilaria sinensis Gilb (ASG). Conclusions : As a result, the vessels of AAR with the resin adsorption was packed with lots of yellow-brownish materials, which were quite different from those of IAW and ASG. The cell walls were thick, and had well-developed traumatic parenchyma tissues with squared cells of the same height and width, which appeared as a clump of small grains packed.

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Indoor Noise Analysis of Naval Combat Service Support Boat (전투근무지원정 격실의 실내소음 분석)

  • Park, Mi-You;Han, Hyung-Suk;Cho, Heung-Gi
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.21 no.7
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    • pp.609-614
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    • 2011
  • The ship working environment of combat service support boat is much inferior to the ground working environment. For this reason, the crew of a combat service support boat suffer from an occupational disease such as hardness of hearing. Owing to its small size and low status, the improvement of its working and residential environment was occasionally ignored and its indoor noise was not fully investigated. In this study, for improving its residential environment indoor, the indoor noise of its shipboard compartments was analysed. These studies define the indoor noise level of combat service support boat is very high and some of indoor noise is exceeded the criteria for ship noise. Compared with marine police vessels, the indoor noise levels of marine police vessels are higher than the level of combat service support boat.

Two-stage Surgical Treatment of a Giant Solitary Fibrous Tumor Occupying the Thoracic Cavity

  • Song, Joon Young;Kim, Kyung Hwa;Kuh, Ja Hong;Kim, Tae Youn;Kim, Jong Hun
    • Journal of Chest Surgery
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    • v.51 no.6
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    • pp.415-418
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    • 2018
  • A solitary fibrous tumor (SFT) is a mesenchymal fibroblastic tumor inside the pleura, for which complete surgical resection is the standard treatment. For large SFTs, preoperative identification of tumor-feeding vessels using angiography is important for achieving complete resection without unexpected operative bleeding. Extensive adhesions can make resection difficult in a limited operative window, and pulmonary resection may be required to achieve complete SFT resection. Herein, we report successful resection of a large pleural SFT in a 39-year-old man without any complications using a 2-stage approach, in which ligation of the feeding vessels through small another operative window was the first step.

Analysis and 3D Reconstruction of a Cerebral Vascular Network Using Image Threshold Techniques in High-resolution Images of the Mouse Brain (쥐 뇌의 고해상도 이미지에서 임계화 기법을 활용한 뇌혈관 네트워크 분석 및 3D 재현)

  • Lee, Junseok
    • Journal of Korea Multimedia Society
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    • v.22 no.9
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    • pp.992-999
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    • 2019
  • In this paper, I lay the foundation for creating a multiscale atlas that characterizes cerebrovasculature structural changes across the entire brain of a mouse in the Knife-Edge Scanning Microscopy dataset. The geometric reconstruction of the vascular filaments embedded in the volume imaging dataset provides the ability to distinguish cerebral vessels by diameter and other morphological properties across the whole mouse brain. This paper presents a means for studying local variations in the small vascular morphology that have a significant impact on the peripheral nervous system in other cerebral areas, as well as the robust and vulnerable side of the cerebrovasculature system across the large blood vessels. I expect that this foundation will prove invaluable towards data-driven, quantitative investigations into the system-level architectural layout of the cerebrovasculature and surrounding cerebral microstructures.

Influence of viscous effects on numerical prediction of motions of SWATH vessels in waves

  • Brizzolara, Stefano;Bonfiglio, Luca;Medeiros, Joao Seixas De
    • Ocean Systems Engineering
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    • v.3 no.3
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    • pp.219-236
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    • 2013
  • The accurate prediction of motion in waves of a marine vehicle is essential to assess the maximum sea state vs. operational requirements. This is particularly true for small crafts, such as Autonomous Surface Vessels (ASV). Two different numerical methods to predict motions of a SWATH-ASV are considered: an inviscid strip theory initially developed at MIT for catamarans and then adapted for SWATHs and new a hybrid strip theory, based on the numerical solution of the radiation forces by an unsteady viscous, non-linear free surface flow solver. Motion predictions obtained by the viscous flow method are critically discussed against those obtained by potential flow strip theory. Effects of viscosity are analyzed by comparison of sectional added mass and damping calculated at different frequencies and for different sections, RAOs and motions response in irregular waves at zero speed. Some relevant conclusions can be drawn from this study: influence of viscosity is definitely non negligible for SWATH vessels like the one presented: amplitude of the pitch and heave motions predicted at the resonance frequency differ of 20% respectively and 50%; in this respect, the hybrid method with fully non-linear, viscous free surface calculation of the radiation forces turns out to be a very valuable tool to improve the accuracy of traditional strip theories, without the burden of long computational times requested by fully viscous time domain three dimensional simulations.

Microvascular Decompression for Glossopharyngeal Neuralgia : Clinical Analyses of 30 Cases

  • Kim, Mi Kyung;Park, Jae Sung;Ahn, Young Hwan
    • Journal of Korean Neurosurgical Society
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    • v.60 no.6
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    • pp.738-748
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    • 2017
  • Objective : We present our experience of microvascular decompression (MVD) for glossopharyngeal neuralgia (GPN) and evaluate the postoperative outcomes in accordance with four different operative techniques during MVD. Methods : In total, 30 patients with intractable primary typical GPN who underwent MVD without rhizotomy and were followed for more than 2 years were included in the analysis. Each MVD was performed using one of four different surgical techniques : interposition of Teflon pieces, transposition of offending vessels using Teflon pieces, transposition of offending vessels using a fibrin-glue-coated Teflon sling, and removal of offending veins. Results : The posterior inferior cerebellar artery was responsible for neurovascular compression in 27 of 30 (90%) patients, either by itself or in combination with other vessels. The location of compression on the glossopharyngeal nerve varied; the root entry zone (REZ) only (63.3%) was most common, followed by both the REZ and distal portion (26.7%) and the distal portion alone (10.0%). In terms of detailed surgical techniques during MVD, the offending vessels were transposed in 24 (80%) patients, either using additional insulation, offered by Teflon pieces (15 patients), or using a fibrin glue-coated Teflon sling (9 patients). Simple insertion of Teflon pieces and removal of a small vein were also performed in five and one patient, respectively. During the 2 years following MVD, 29 of 30 (96.7%) patients were asymptomatic or experienced only occasional pain that did not require medication. Temporary hemodynamic instability occurred in two patients during MVD, and seven patients experienced transient postoperative complications. Neither persistent morbidity nor mortality was reported. Conclusion : This study demonstrates that MVD without rhizotomy is a safe and effective treatment option for GPN.

Neo- and Re- Vascularization in the Prefabricated Cutaneous Flap using Vascular Pedicle Implantation (혈관경 전위를 이용한 선조작 피부피판의 혈관화)

  • Lee, Byung-Il
    • Archives of Reconstructive Microsurgery
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    • v.11 no.2
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    • pp.125-134
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    • 2002
  • This study was designed to investigate the process of re- or neo-vascularization in the prefabricated cutaneous flap using a skeletonized arteriovenous pedicle implantation. Fourty-eight flaps were divided into six groups of eight flaps, including control group of the conventional epigastric flap. In experimental groups, skin flap was fabricated by subcutaneous implantation of a distally ligated saphenous arteriovenous pedicle in left abdomen. At 2, 4, 6, 8, and 10 weeks after, prefabricated flap was elevated as an island flap based on implanted pedicle and sutured back in place. Three days after flap repositioning, the area of flap viability was quantified, the pattern of flap vascularization was evaluated with microangiography, and the quantification of vessels was assessed histologically. There were statistically significant differences in flap viability between group 2, 3, 4, and the control (p<0.05), with increased survival area in order. But Group 5 and 6 showed higher flap viability as much as the control did. In the microangiographis study, numerous small meander vessels were newly developed in the vicinity of the implanted pedicle just only 2 weeks after pedicle implantation, but neovascularization around the tip of implanted pedicle, and its anastomosis with native vasculatures was more important for overall flap survival, which was usually developed at least 4 weeks after pedicle implantation. Histologically, vessels are evenly spread over all layers of the flap at 6 weeks after pedicle implantation. The quantification of vessels was correlated well with the improvement of flap viability (p<0.05). In conclusion, neo- and re-vascularization around the tip of implanted pedicle was an important factor for overall survival of the prefabricated flap. Therefore, skeletonized pure vascular pedicle transfer, even though it used alone without surrounding was sufficient to get higher flap viability. The optimal duration of pedicle implantation was8 weeks to obtain maximal survival.

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The Centralized management method of vessels information for VTS (해상교통관제시스템을 위한 중앙집중형 선박정보 관리 방안)

  • Oh, Seung-Hee;Choi, JoongYong;Lee, Byung-Gil
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.05a
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    • pp.518-521
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    • 2016
  • Korea is surrounded on three sides by the sea, through the maritime transportation accounts for close to 90% share in the total cargo volume. In addition, there are amount of small and medium-sized fishing vessels registered. These days, a number of maritime accidents caused many casualties and having an adverse effect on the marine environment. Therefore, there is a need for a maritime traffic control has been increasing. Information about the ship is divided into AIS information for VTS, Port Management Information System (Port-MIS) operated by the Port and vessels pass (VPASS) that are installed on fishing. However, there is a problem that is not achieved the information exchanged between each other. That is, information on the vessel are stored in diverse inefficient in the management, operation and utilization. This paper discusses the ways to efficiently manage and integrate vessels information for VTS, and proposes the method for implementation and application.

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A Study on the Selection of Subject Vessel for Development of Oil Recovery Equipment for Small Vessel (소형선박용 기름회수장비 개발을 위한 대상선박 선정에 관한 연구)

  • Lim, Chae-Hyun;Han, Won-Heui
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.18 no.6
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    • pp.604-609
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    • 2012
  • Our country has experienced some difficulties with clean up operation of massive marine oil pollution due to the lack of oil spill response equipments. And there was the case that a fishing vessel performed clean up operation had not received any proper payments because of its inefficient oil spill response operation. Thus, it is important to develop an efficient oil recovery equipment for small vessel and adopt it as a part of oil pollution prevention policy. These efforts could prepare oil spill response equipment in advance and use a fishing vessel registered in the affected area by massive marine oil pollution. Therefore, this study examines and adopts a suitable subject vessels as a first step for developing oil recovery system fitting with small vessels for national use.