• Journal of the Society of Naval Architects of Korea
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• v.58 no.4
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• pp.225-233
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• 2021

Conventional submarine propulsion batteries have mainly used lead acid batteries, which have proved relatively safe, but in recent years, research on mounting lithium-ion batteries to improve the underwater operation capability of submarines is underway in advanced countries such as Japan. Korea has world-class technology in the development of electric vehicles and lithium-ion batteries for energy storage, but fire safety accidents continue to occur in electric vehicles and energy storage lithium-ion batteries. In order to mount the lithium-ion battery in a submarine, it is necessary to check the safety as well as whether the performance is improved compared to the lead acid battery. Through the charge/discharge experiment of this lithium-ion battery module unit, it was possible to measure how much performance was improved compared to the lead acid battery. Safety tests were conducted on the lithium-ion battery module assuming that it was mounted on a submarine, and it was confirmed that safety was secured when applied to a submarine. Since many modules are mounted on actual submarines, it has been confirmed that it can be applied to submarine systems by simulating charge/discharge characteristics through Hardware-in-the Loop(HILS). Through the results of this study, the application of lithium-ion batteries to submarines is expected to significantly improve the sustainability of underwater operations.

• Journal of Chest Surgery
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• v.57 no.4
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• pp.399-407
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• 2024

Background: Pump-controlled retrograde trial off (PCRTO) is a safe, simple, and reversible method for weaning patients from veno-arterial extracorporeal membrane oxygenation (VA-ECMO). However, few studies have compared PCRTO to conventional weaning methods. This retrospective study aimed to compare PCRTO to non-PCRTO methods. Methods: This study included patients who were weaned from VA-ECMO from January 2016 to December 2022 at our medical center. Demographic data, ECMO management, ECMO complications, survival to discharge, and cardiogenic shock after VA-ECMO weaning were compared between the 2 groups. Results: Seventy patients who were weaned from VA-ECMO using PCRTO and 85 patients who were weaned with conventional methods were compared. Patient characteristics were not significantly different between the 2 groups. The rate of survival to discharge was significantly higher in the PCRTO group than in the non-PCRTO group (90% vs. 72%, p=0.01). The rates of freedom from all-cause mortality at 10, 30, and 50 days after weaning from ECMO were 75%, 55%, and 35% in the non-PCRTO group and 62%, 60%, and 58% in the PCRTO group, respectively (p=0.1). The incidence of cardiogenic shock after weaning from VA-ECMO was significantly higher in the non-PCRTO group (16% vs. 5%, p=0.04). In logistic regression analysis, PCRTO was a significant factor for survival to discharge (odds ratio, 2.42; 95% confidence interval, 1.29-5.28; p=0.02). Conclusion: Compared to conventional methods, PCRTO is a feasible and reversible method, and it serves as a useful predictor of successful VA-ECMO weaning through a preload stress test.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.326-327
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• 2006

The paper describes the development of arrester for 154kV class power station and substation. The arrester employs silicone insulating materials for Its housing, instead of the conventional porcelain housing. The sealing integrity is related to safe operation of surge arrester, the prime failure reason of porcelain housed arresters is moisture ingress. In this paper, the sealing integrity of polymeric surge arresters for ultra high voltage is investigated with moisture ingress test. The diagnostic techniques are discusses, including watt loss, partial discharge, AC leakage current, 1mA DC voltage and residual voltage.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.5
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• pp.959-965
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• 2014

Transporting of live fish requires subcontract with an independent contractor. During the transporting of live fish, civil liability problems can be caused by damage of fish. Before transporting of live fish, responsibility of negligence and tort liability were arisen, after transporting of live fish, default on an obligation was arisen. To avoid this problems, it is important to put a bond on each other and live fish transporting contract can be made a legal contract. Also, transporting of live fish must be made safe, after transporting, and discharge of obligation, perfect transaction is achieved.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.431-434
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• 2003

This research developed a method for the estimation of groundwater recharge by yielding daily soil moisture content and watershed evapotranspiration from the water balance concept of the unsaturated and saturated layers in rainfall-runoff model called DAWAST. The goal of the research is to estimate the groundwater recharge fulfilling conditions of the safe discharge for any season. To meet this goal, the data of groundwater level and stream flow rate have been monitored in a study area and used to validate the model.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.47-53
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• 2006

The oxidizer-rich preburner is applied to the high efficiency closed cycle rocket propulsion system. This system is generally operated on oxidizer-fuel mixture ratio over than 50. The spray quality and mixing performance are very important for safe combustion of this preburner. This paper presents basic concept and spray characteristic of the preburner injector.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.12
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• pp.64-70
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• 1994

In this paper, we inverstigated how a parricular internal inverter circuit, which is located far from the input protection in CMOS DRAM, can be easily damaged by external ESD stress, while the protection circuit remains intact. It is shown in a mega bit DRAM that the internal circuit can be safe from ESD by simply improving the input protection circuit. An inverter, which consists of a relatively small NMOSFET and a very large PMOSFET, is used to speed up DRAMs, and the small NMOSFET is vulnerable to ESD in case that the discharge current beyond the protection flows through the inverter to Vss or Vcc power lines on chip. This internal circuit damage can not be detected by only measuring input leakage currents, but by comparing the standby and on operating current before and after ESD stressing. It was esperimentally proven that the placement of parasitic bipolar transistor between input pad and power supply is very effective for ESD immunity.

• Journal of Industrial Technology
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• v.26 no.B
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• pp.43-51
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• 2006

Through the result of calculating the deviation between the value calculated from two-dimensional number formula, one-dimensional number interpretation, and curving part water surface type calculation method, we could confirmed that the deviation is reduced more than 50% when we use curving part water surface type calculation method. Also it was confirmed that there occurs the reduction rate of maximum 59% as the result of comparing with one-dimensional number interpretation since the reduction rate of safe room height was 20%, in 500 CMS of flood water quantity when we planted the construction of levee by curving part water surface type calculation method. And therefore, we have confirmed that the curving water surface type calculation method can be used as a simple formula in rivers with water quantity less than 500 CMS that flows in and out in Jess than 90 degree angle.

• Structural Engineering and Mechanics
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• v.62 no.4
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• pp.487-496
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• 2017

The focus of this study were to investigate patterns between wall pressures and stresses with grain moisture of soybean and rice varieties widespread cultivated in Turkey in order to determine needed designing parameters for structure analysis in silos at filling and discharge. In this study, the wall pressures and stresses were evaluated as a function of moisture contents in the range of 8-14% and 10-14% d.b. The pressures and von Mises stresses affected as significant by the change of grain moisture content. The main cause of pressure and stress drops is changed in bulk density. Therefore is extremely important bulk density and moisture content of the product at the structural design of the silos. 4 mm wall thickness, were determined to be safe for von Mises stresses in both soybean and rice silos is smaller than 188000 kPa.

• Korean Medical Education Review
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• v.19 no.3
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• pp.152-157
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• 2017

Interprofessional education (IPE) fosters effective team-based collaborative practice among members of different health care professions to advance high-quality and safe patient care. Although the importance of IPE has been recognized and IPE initiatives have expanded rapidly in the past decades, substantial difficulties in IPE assessment still exist. At present, a lack of consensus on the optimal approach to IPE assessment contributes to uncertainty about the level of attainment of collaborative team performance. This paper aims to provide an overview of the benefits and current challenges associated with IPE assessment. Furthermore, a multifactor model with an assessment matrix and assessment blueprints from a recent study is briefly discussed. We also provide examples of assessment blueprints for the team management of stroke patient discharge covering a competency examination at the levels of individuals, the team, and the task.