• Annual Conference on Human and Language Technology
• /
• 2019.10a
• /
• pp.326-329
• /
• 2019

기계독해를 실용화하기 위해 단락을 검색하는 검색 모델은 최근 기계독해 모델이 우수한 성능을 보임에 따라 그 필요성이 더 부각되고 있다. 그러나 기존 검색 모델은 질의와 단락의 어휘 일치도나 유사도만을 계산하므로, 기계독해에 필요한 질의 어휘의 문맥에 해당하는 단락 검색을 하지 못하는 문제가 있다. 본 논문에서는 이러한 문제를 해결하기 위해 Word2vec의 입력 단어열의 벡터에 해당하는 IN Weight Matrix와 출력 단어열의 벡터에 해당하는 OUT Weight Matrix를 사용한 단락 검색 모델을 제안한다. 제안 방법은 기존 검색 모델에 비해 정확도를 측정하는 Precision@k에서 좋은 성능을 보였다.

• Proceedings of the KIEE Conference
• /
• 2001.11a
• /
• pp.81-83
• /
• 2001

새로이 제안한 이중 애노드 LIGBT(Dual Anode LIGBT)는 빠른 스위칭을 위한 기존의 단락 애노드 구조를 캐소드의 양쪽에 위치시킴으로써 단락 애노드 구조가 갖는 부성저항영역을 효과적으로 제거했다. 뿐만 아니라 순방향전압강하 또한 기존의 분리된 단락 애노드 LIGBT (Seperate Shorted Anode LIGBT)에 비해 30%의 개선 효과를 갖는다.

• Proceedings of the KWS Conference
• /
• 2001.10a
• /
• pp.33-36
• /
• 2001

• Journal of Chest Surgery
• /
• v.29 no.2
• /
• pp.147-152
• /
• 1996

his study was undertaken to assess the residual interventricular shunt following surgical closure of the isolated ventricular septal defect. From January 1989 through December 1993, 211 patients underwent surgical closure of the isolated ventricular septal defect. All patients had 2D-Echocardlo-graphic study after operation to rule out residual ventricular septal defect. There was a 9.5% incidence of a definite residual shunt. The type of ventricular septal defect, closure method of the defect and cardiopulmonary bypass time showed no significant differences between two groups. The sue of ventricular septal defect (6.3 $\pm$ 3.7mm versus 10.6 $\pm$ 5.8mm : p : 0.0034), aortic cross-clamping time(32.6 $\pm$ 15.0 minutes versus 48.5 $\pm$ 20.0 minutes, p : 0.0003), pulmonary-to-systemic pressure ratio(0.31 $\pm$ 0.22 versus 0.51 $\pm$ 0.33, p=0.019) and mean pulmonary artery pressure(20.3 $\pm$ 11.9 mmHg versus 29.1 $\pm$ 16.2 mmHg, p : 0.009) were meaningfully different between two groups. There were 9 insta ces of spontaneous closure of the residual shunts at mean 21 months of following up (ranged 1 ~43 months). In conclusion, we suggest that the size of ventricular septal defect, aortic cross-clamping time and mean pulmonary artery pressure may play an important role in occurance of residual ventricular septal defect.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.5 no.4
• /
• pp.39-49
• /
• 2001

In this paper, inelastic analysis procedures are presented for the seismic performance evaluation of RC bridge piers with premature termination of main reinforcement. The mechanical characteristic of cracked concrete and reinforcing bar in concrete has been modeled, considering the bond effect between reinforcing bars and concrete, the effect of aggregate interlocking at crack surface and the stiffness degradation after the crack. The smeared crack approach is incorporated. In boundary plane at which each member with different thickness is connected, local discontinuous deformation due to the abrupt change in their stiffness can be taken into account by introducing interface element. The increase of concrete strength due to the lateral confining reinforcement has been also taken into account to model the confined concrete. The proposed numerical method for seismic performance evaluation of RC bridge piers with premature termination of main reinforcement will be verified by comparison with reliable experimental results.

• Proceedings of the KIPE Conference
• /
• 2010.07a
• /
• pp.43-44
• /
• 2010

본 논문에서는 저전압 구동 인버터의 게이트 구동회로 설계 시, 밀러 캡 영향이 야기할 수 있는 암 단락 현상 방지를 위한 양전원 방식의 게이트 구동회로 설계를 제안한다. 제안하는 회로는 부트스트랩 방식의 0~15[V] 의 전원을 사용하고, 커패시터와 다이오드를 통하여 마이너스 전압을 생성하며 이를 통해 양전원으로 게이트를 구동한다. 이는 단 전원 방식에 비하여 밀러 캡의 영향을 줄일수 있고 이를 통해 스위칭 시 소자의 스트레스를 감소시키며 또한 암단락을 방지한다. 제안하는 회로를 시뮬레이션과 실험을 통해 검증하였다.

• Proceedings of the KIPE Conference
• /
• 2010.07a
• /
• pp.446-447
• /
• 2010

본 논문에서는 전동기의 고정자 권선 절연파괴 고장을 분석하고 자기 인덕턴스 변화의 비선형성을 고려하기 위해 FEM 시뮬레이션을 이용하여 고장 현상을 해석하고, 실험을 통해 검증하였다. 제안한 고장의 모델링을 통하여 고정자 권선에서 단락이 발생하면 단락된 권선의 순환전류에 의해 고정자에 자기 포화현상이 발생하고, 입력전류의 불평형에 의하여 평균토크가 감소하고, 토크리플이 증가함을 확인 하였다.

• Journal of Ocean Engineering and Technology
• /
• v.16 no.2
• /
• pp.53-59
• /
• 2002

This paper shows the experimental results controlling the height of surface and back bead in GMAW by analyzing the unexpected gaps between base metals produced in welding and by controlling welding velocity due to the variation of the gap between base metals in thin-plate welding. The back bead behavior and burn-through in I-type butt joint $CO_2$ welding of thin mild steel are analyzed in the views of short circuit time ratio and short circuit frequency. It is shown through experimental consideration that the short circuit time ratio method is more reasonable than the short circuit frequency method in analyzing the formulation of back bead under changing the gap between base metals. Based on the these results, welding manipulator is designed so as to satisfy the bead height control in real time by measuring the short circuit time ratio. To show the effectiveness of the developed bead formulation control system, the experiment is implemented under two welding conditions such as increasing gap from 0mm to 0.8mm and gradually increasing gap from 0mm to 1.2mm. The experimental results show that the bead formulation can be controlled uniformly in spite of the variation of the gap between base metals.

• Proceedings of the KIEE Conference
• /
• 2005.11a
• /
• pp.74-76
• /
• 2005

수평형 에미터 스위치트 사이리스터(Lateral Emitter Switched Thyristor, LEST)의 고전압 전류 포화 특성을 위한 새로운 보호회로가 제안하였으며 성공적으로 제작 및 측정하였다. LEST의 부유(浮遊, floating) n+ 전압이 보호 MOSFET의 문턱 전압 보다 커지면 보호 회로는 LEST의 동작 모드를 regenerative 상태에서 non-regerative 상태로 전환시킨다. 일반적인 LEST의 전압 전류 포화 특성이 17 V로 제한되는 것에 비해 제안된 회로와 결합된 LEST는 200V 이상의 고전압 전류 포화 특성을 보였으며, Hard Switching Fault(HSF) 단락 회로 상황에서도 $10{\mu}s$ 이상 견디는 단락 회로 유지 능력을 보였다.

• Water for future
• /
• v.28 no.4
• /
• pp.147-154
• /
• 1995

Scour characteristics of noncohesive bed materials at the downstream of free-falling jet were analyzed through hydraulic experiments. It was assumed that the downstream had no special energy dissipators. Flow characteristics of free falling jet from rectangular section were studied, and scour characteristics with and without mounds, which were generated at the downstream of the scour hole, were comparatively analyzed for various bed materials, discharges and tailwater depths. Not only the equilibrium scour depth but also the height of mound could be expressed as a function of densimetric Froude number. Densimetric Froude number had closer relationship with the equilibrium dimensionless scour depth than other dimensionless parameters. It was suggested that the mound effects should be considered at the design stage of bed protection works.