• Title/Summary/Keyword: Small Vessels

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Elastic/Plastic High-temperature Structural Analysis on the Small Scale PHE Prototype (소형 공정열교환기 시제품에 대한 탄소성 고온구조해석)

  • Song, Kee-nam;Lee, H-Y;Hong, S-D;Park, H-Y
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.7 no.2
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    • pp.1-6
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    • 2011
  • PHE(Process Heat Exchanger) is a key component required to transfer heat energy of $950^{\circ}C$ generated in a VHTR(Very High Temperature Reactor) to the chemical reaction that yields a large quantity of hydrogen. Korea Atomic Energy Research Institute established a small-scale gas loop for the performance test of components, which are used in the VHTR, and they manufactured a PHE prototype made of Hastelloy-X to be tested in the small-scale gas loop. Results from the elastic structural analysis on the PHE prototype were reported in the previous article. In order to investigate the macroscopic structural characteristics and behavior of the PHE prototype under the test condition of the small-scale gas loop far more in detail, elastic-plastic high-temperature structural-analysis of the PHE prototype was carried out in this study.

A Study on the Development of an Engine Monitoring System for Small Vessel Using CSMA/CD (CSMA/CD 프로토콜을 이용한 중.소형 선박용 기관 모니터링 시스템 구성에 관한 연구)

  • 신명철;고두석;윤경국;안병원;김윤식
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.3 no.2
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    • pp.455-463
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    • 1999
  • This study is on the development of an engine monitoring system which can be applied not only for mid-size vessels but also small vessels less than 20 gross tonnage. Monitoring system consists of a set LMU(Local Monitoring Unit) that collect data from local machinery, a host computer that controls LMU and a stable communication system which adopts CSMA/CD protocol. The LMU is composed of 80C196KC microprocessor, which consists of CPU, digital input/output, analog input/output and communication module. Communication system between the host computer(compatible IBM PC) and LMUs is the multidrop configuration using RS-485 method and confirmed high performance communication by the aid of polling method as well as carrier sense multiple access with collision detection(CSMA/CD) protocol.

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Manufacture for living supplies of Chestnut wood(Castanea crenata Sieb. et Zucc)

  • Kim, Sa-Ick;Lee, Seong-An;Kim, Dong-Kooi
    • Journal of the Korea Furniture Society
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    • v.20 no.6
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    • pp.575-580
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    • 2009
  • This study was carried out to manufacture wooden vessels by small diameter wood and wasted wood of Castanea crenata Sieb. et Zucc, which has been largely planted in southern area. We made spice set, tea box set, cookie vessel set, bowl set and accessory set. With the development of edged tools, the human species has been able to fashion wood to change and enhance its environment - one only has to look at the history of all cultures to see examples of wooden artifacts and structures. Even with the development of synthetic materials and the progress of automated, mechanized production of wood and wood products, the raw material is still processed by traditional methods to meet a never-ending demand for products made from this most desirable natural material. Chestnut wood has high added value and natural color grain and is very useful for wooden vessel. Thinned low grade trees can be used to produce wooden vessel. Therefore this result can promote thinning and produce good forestation.

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Rapid progression of large intracranial cerebral artery involvement in a patient with myeloperoxidase antineutrophil cytoplasmic antibody-associated vasculitis

  • Jihee Ko;Jay Chol Choi
    • Journal of Medicine and Life Science
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    • v.21 no.1
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    • pp.15-19
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    • 2024
  • Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a systemic necrotizing vasculitis that predominantly affects small vessels of the body. The two most common ANCAs are myeloperoxidase ANCA and proteinase 3 ANCA. Neurological manifestations are frequent in patients with AAV, including peripheral neuropathy, meningitis, and stroke. AAV-associated ischemic stroke usually affects small vessels supplying the white matter or brainstem. This case report details the presentation and treatment course of a 70-year-old man with rapidly progressive multiple intracranial large artery involvement attributed to myeloperoxidase ANCA-associated vasculitis. Despite treatment with high-dose steroids and a rituximab infusion, the patient developed new speech difficulties and respiratory distress, and brain imaging confirmed new stroke lesions with progressive multiple intracranial large cerebral artery involvement. The patient died from SARS-CoV-2 infection 4 months after the diagnosis. This case emphasized the rare presentation of rapidly progressive large vessel involvement in a patient with myeloperoxidase ANCA-associated vasculitis despite active immunotherapy.

A Study on the Analysis of Traffic Distribution and Traffic Pattern on Traffic Route using ND-K-S (ND-K-S를 적용한 항로 통항분포와 통항패턴 분석에 관한 연구)

  • Kim, Jong-Kwan
    • Journal of Navigation and Port Research
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    • v.42 no.6
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    • pp.446-452
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    • 2018
  • A traffic route is an area associated with high risk for accidents due to the flow of heavy traffic. Despite this concern, most studies related to traffic focus solely on traffic distribution. Therefore, there is a need for studies investigating the characteristics of ships' routes and traffic patterns. In this study, an investigation was carried out to analyze the traffic distribution and pattern in 3 major traffic routes for 3 days. For the purpose of the study, based on the prevailing traffic conditions, the route was divided into 10 gate lines. The ships passing through the lines were also classified into either small, medium and large. ND-K-S (normal distribution, kurtosis, and skewness) test was carried out for the traffic distribution at each gate line based on the information analyzed on each traffic route. The analysis of the results obtained from the ND test showed that large vessels have normal distribution, medium sized vessels have satisfied normal distribution in one-way route only while small sized vessels do not have normal distribution. According to the result obtained from the K-S test, normal traffic pattern shows a significant difference between two-way route and one-way route. Results obtained from the K test result shows that in the case of one-way route, vessels have a traffic pattern using a wide range on traffic route. Further analysis shows that vessels concentrate on one side of route in case of two-way route. Results obtained from the S test show that, in case of one-way route, vessels have a normal traffic pattern according to center line. However, analysis pf the results shows that vessels are shifted to the right side of route in case of two-way route. Despite these findings, it should be noted that this study was carried out in only 3 ports, therefore there is need for investigation to be carried out in various routes and conditions in future studies.

Redefinition of the Concept of Fishing Vessel and Legislation Adjustment (낚시어선 개념의 재정립과 법제 정비에 관한 연구)

  • Yeong-Tae Son
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.6
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    • pp.639-652
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    • 2023
  • The fundamental background behind the introduction of the fishing vessel system is to allow petty small fishers to engage in pure fishery business activities with fishing vessels during normal times and engage in fishing vessel business only during specific periods (closed fishing season, etc.) thereby granting a qualification as an auxiliary tool for the economic activities of petty small fishers. In addition, fishing boats are allowed to engage in excursion ship activities using fishing vessels registered under the Fishing Vessels Act, the form of fishing vessels should also have a general and universal structure that is practically easy to engage in fishing activities in the field in accordance with the relevant regulations. However, most fishing vessel proprietors are currently focusing only on increasing income, and rather than building fishing vessels in a reasonable form suitable for the original purpose of general fishing vessels, they prefer an abnormal hull form equivalent to expediency, that is biased hull structure biased toward the fishing vessel business. As a result, it is causing serious problems in safety management as well as conflict [damaging relative equity in government support measures (tax-free oil supply, etc.), and depletion of livelihood-type fish stocks] with fishing vessel forces who consider the fishing vessel business only to be a part of the side job among all fishery business activities. Meanwhile, the most fundamental cause of this problem is that the current Fishing Management and Promotion Act, limits the concept of fishing vessels to fishing vessels registered under the Fishing Vessels Act, and applies survey standards accordingly. Accordingly, in this study, through analysis of the distribution status of fishing vessels, structural characteristics, operation status of fishing vessels, and the government's fishing promotion policies, etc., the relevant laws (regulations) have been reorganized to suit the current reality of the concept of fishing vessels to separate the current fishing vessel from fishing vessels and operate it as a fishing-only vessel.

Field Experiments and Analysis of Drift Characteristics of Small Vessels in the Coastal Region off Busan Port (부산항 연안해역에서의 소형선박 표류 거동특성 관측 및 분석)

  • Kang, Sin-Young;Lee, Mun-Jin
    • Journal of Navigation and Port Research
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    • v.26 no.2
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    • pp.221-226
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    • 2002
  • To provide reliable data for drift prediction models, field experiments were carried out in the coastal region off Busan port. Four different size of vessels(10, 30, 50, 90G/T ton) were deployed for the experiment. Among them G/T 50ton class vessel was equipped with instruments measuring the currents, winds, headings and trajectory data. In the rest of vessels only the position data were recorded for the purpose of target divergence study. The trajectories of each vessel were measured by DGPS(Differential Global Positioning System) and collected by APRS(Automatic Position Reporting System). The experiment was done in wind of 2~10m/s and current of 0.5~1.5m/s. The leeway was derived by subtracting surface current velocity from target drifting velocity. The leeway rate of G/T 50ton vessel was found to be about 3.6% and the computed leeway speed equation was $U_L$=0.042 W - 0.034. The processed leeway angle data were deflected by $-30^{\circ}$~$40^{\circ}$ from the direction of ship drift.

Bilateral Coronary Artery-Pulmonary Artery Fistula - Reports of a Case- (양측 관상동맥-폐동맥간 동맥루 치험 1례)

  • 문경훈
    • Journal of Chest Surgery
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    • v.21 no.3
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    • pp.583-587
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    • 1988
  • Bilateral coronary artery-pulmonary artery fistula is very uncommon congenital heart disease which occupy small percentage of all coronary arterio-venous fistulas. We experienced a case who was 52 years old female with bilateral coronary artery-pulmonary artery fistula. She complained exertional dyspnea k angina[coronary steal syndrome]. On physical examination, any cardiac murmur was not audible. There was no 0y step-up in right heart catheterization. But selective coronary angiography revealed tortuous aberrant vessels which originated from the canal branch of the right coronary artery k the left anterior descending coronary artery. Both aberrant vessels traversed the right ventricular outflow tract, and conjoined just proximal the pulmonic annulus and drained into the main pulmonary artery. The operation was performed under the extracorporeal circulation with beating heart. The procedures were suture-ligation of the draining orifice in main pulmonary artery & the feeding vessels on the right ventricular outflow tract. Postoperatively her complaints were completely disappeared and the selective coronary angiography revealed no left-to-right shunt.

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A Study on Some Consideration of Marime Casualities and Prevention Measures against them of Vessels engaged in Near-coastal and Greater-coasting Seas (연.근해 운항선박의 해난실태와 사고방지대책)

  • 윤점동;이윤철
    • Journal of the Korean Institute of Navigation
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    • v.15 no.1
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    • pp.67-93
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    • 1991
  • In general, marine casualities take palace by the composite action of three elements such as waterway condition, vessel condition and man condition. One of the important characteristics of most marie casualties for small cargo vessels in maritime transportation of near-coastal and greater-coasting seas in that the same kind of casualities take place repeatedly in spite of the apprent causes, Because, it takes much time and effort for seamen to master waterway, vessel or operatin technique only to the practical and sensible level. In these days, with the development of our economy, our shiypping industry has grown and therefore the demand of marine officers has increased. This economic growth brought about undesirable situation like the evasion of seamen and frequent casualities of Korea vessels. These marine casualities are being caused mainly by the unskilfulness of operating technique as well as the bad waterway condition and ship's installation condition. Therefore, I conclude, in this paper, that the most efficient and economic preventing measures of marine casualities are seeking causes and removing them in advance under the close coperation system among all concerned parties.

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A Fast Lower Extremity Vessel Segmentation Method for Large CT Data Sets Using 3-Dimensional Seeded Region Growing and Branch Classification

  • Kim, Dong-Sung
    • Journal of Biomedical Engineering Research
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    • v.29 no.5
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    • pp.348-354
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    • 2008
  • Segmenting vessels in lower extremity CT images is very difficult because of gray level variation, connection to bones, and their small sizes. Instead of segmenting vessels, we propose an approach that segments bones and subtracts them from the original CT images. The subtracted images can contain not only connected vessel structures but also isolated vessels, which are very difficult to detect using conventional vessel segmentation methods. The proposed method initially grows a 3-dimensional (3D) volume with a seeded region growing (SRG) using an adaptive threshold and then detects junctions and forked branches. The forked branches are classified into either bone branches or vessel branches based on appearance, shape, size change, and moving velocity of the branch. The final volume is re-grown by collecting connected bone branches. The algorithm has produced promising results for segmenting bone structures in several tens of vessel-enhanced CT image data sets of lower extremities.