• 전력전자학회논문지
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• 제13권5호
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• pp.383-390
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• 2008

본 논문은 산업현장에서 중요부하에 안정적인 전원공급을 하기 위하여 설치한 Static Transfer Switch (STS)의 사이리스터(SCR)가 평균 2%대의 고장으로 문제가 되고 있어 이를 방지하고자 SCR 양단에 기계적인 접점스위치를 병렬로 연결시키고 SCR은 병렬스위치가 동작 가능한 구간인 $12{\sim}208$[mS] 구간에만 기능을 수행하도록 구성하였다. 또한 두 개의 입력 중 어느 한쪽이 단락 또는 지락 사고가 발생되더라도 다른 한쪽의 경로와 부하에 영향을 주지 않도록, 두 개의 입력이 동시 투입되는 시간을 차단하는 ISC (Ideal State Conditioning Interlock Device) - STS 시스템을 제안하였다. 이 제안으로 년간 0.89회의 전환 동작 시에만 SCR이 역할을 하고 전환시점 이후에는 병렬스위치가 전원공급계통의 역할을 함으로서 SCR의 피로도를 현저히 감소시켜 고장률을 감소시킬 뿐만 아니라 고장이 발생된 경우라도 부하에는 영향을 미치지 않아 중요부하의 전원공급에 대한 신뢰성을 높이는데 기여할 수 있다.

• Journal of Advanced Research in Ocean Engineering
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• 제3권2호
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• pp.66-74
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• 2017

Since risers have to be operated without being replaced during the design life time after installation, fatigue evaluation as well as strength analysis should be performed. The fatigue life of the riser is known to be dominantly influenced by wave loading and vortex induced vibration (VIV) phenomena. The fatigue life evaluation method and the behavior characteristics of the riser by the wave have been done a lot. Even though the VIV is an important source of fatigue damage for SCR, the evaluation method and behavior characteristics by VIV have not been studied relatively. Most of the S / W for calculating VIV fatigue are a semi-empirical model based on various theoretical models and experiments. For better understanding of VIV response, it is necessary to investigate the effect of parameters which affects the analysis result. This paper summarizes the results of parametric study performed to enhance the understanding of relationship between each parameter and fatigue analysis result.

• 한국임상약학회지
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• 제8권1호
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• pp.23-28
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• 1998

The pharmacokinetics of atenolol (25 mg/kg, i.v.) in the folate-induced renal failure rabbits was studied. Renal failure was induced by the i.v. injection of folate (50, 100, and 200 mg/kg). At folate dose of 100 and 200 mg/kg, the serum creatinine concentration (Scr) and blood urea nitrogen (BUN) increased significantly compared with control rabbits. Plasma concentrations and AUC of atenolol increased significantly at folate dose of 100 and 200 mg/kg. The elimination rate constant $(K_{el})$ and total body clearance $(CL_t)$ of atenolol decreased significantly, and half-life ($t_{1/2}$) and mean residence time (MRT) of atenolol increased significantly at folate dose of 100 and 200 mg/kg. The serum creatinine concentration $(S_{cr})$ correlated well (p<0.05) with half-life $(t_{1/2})$ and elimination rate constant $(K_{el})$ of atenolol, as well as BUN with AUC and total body clearance $(CL_t)$ of atenolol.