• 한국통신학회논문지
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• 제31권12C호
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• pp.1208-1215
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• 2006

본 논문에서는 스테레오 카메라로 입체 동영상을 얻는 방법이 아닌 H.264로 압축된 2D 동영상으로부터 복호화 과정에서 얻게 되는 움직임 정보를 이용하여 효과적인 3D 입체 동영상을 생성하는 기법을 제안한다. MPEG 기반의 동영상에서 각 프레임의 움직임 정보는 복호화단에서 얻게 되는 움직임 벡터로 분석이 가능하며 H.264에서는 움직임 예측을 위하여 다양한 크기의 블록을 이용하기 때문에 더 정확한 움직임 벡터와 정보를 얻을 수 있다. 본 논문에서 제안한 2D/3D 변환기법에서는 장면 전환점 검출, delay factor, 운동 방향, 운동 형태 등을 이용하여 좌영상과 우영상을 생성한다. 이때 동일한 컷(cut)내의 프레임들 간의 운동 형태와 운동 방향은 높은 상관도를 가지게 된다. 실험 결과를 통해서 제안된 기법을 이용할 경우 안정된 동영상 입체 변환이 가능함을 알 수 있다.

• 제어로봇시스템학회논문지
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• 제14권6호
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• pp.564-572
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• 2008

The performance of the direct adaptive time-delay command shaping filter depends on the select time-delay. In the previously introduced direct adaptive command shaping filter, however, the time-delay value is fixed and only the magnitudes of the impulses are learned. In this paper, the authors introduce a new scheme to adapt the time-delay which is to be used in conjunction with the direct adaptive command shaping for the improved vibration suppression in flexible motion system. In order to formulate the time-delay adaptation scheme, the authors have analyzed the effect of the time-delay value on the performance of the direct adaptive command shaping filter. By modifying the direct adaptation formula based on the analysis result the authors have established a set of equations to adapt the time-delay toward the optimal value. Simulation results show the effectiveness of the proposed time-delay adaptation approach for the improved vibration suppression.

• 대한족부족관절학회지
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• 제21권4호
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• pp.151-155
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• 2017

Purpose: Reducing tenderness or pain on the ankle joint and improving the range of motion are thought to be possible using hyaluronate-based anti-adhesive agents. On the other hand, there are more aspects to be studied regarding the incidence of complications, such as resting pain, tenderness, and stiffness, after surgery. Therefore, the aim of this study was to prove the effectiveness of the agents after ankle fracture surgery. Materials and Methods: Patients, who underwent open reduction and internal fixation surgery due to ankle joint fractures from June 2015 to May 2016, were studied prospectively. Thirty patients of them received a $Guardix^{(R)}$ injection during their surgeries and were included in the injection group. The other 30 patients were included in the control group. Postoperatively, tenderness on the scar, a delay in wound healing, and the active range of motion were evaluated at 2, 6, and 12 weeks after surgery. Results: A significant difference in tenderness on the scar was observed 2 weeks after surgery. On the other hand, there was no significant difference at 6 and 12 weeks after the surgery. The agent-using group showed a 6.7% delay in wound healing and a 93.3% nondelaying. In the non-using group, the delay was 63.3%, while non-delay was 36.7% (p<0.001). The group that underwent $Guardix^{(R)}$ usage showed an effective result in the visual analogue scale, which was statistically significant (p<0.001). The result at 6 and 12 weeks after surgery showed a significant difference. Conclusion: Improvement was observed in the patients who underwent a $Guardix^{(R)}$ injection, regarding the range of motion, visual analog scale, and healing of the wound postoperatively.

• 한국정밀공학회지
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• 제17권12호
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• pp.176-184
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• 2000

TDC(Time Delay Control) deals with the time-varying system parameters, unknown dynamics and unexpected disturbances using time delay. TDC can be divided into two separate parts: an auxiliary controller and a servo controller. The two controllers can be designed independently. The auxiliary controller is used to reduce sensitivity to parameter variations, nonlinear effects, and other disturbances. The servo controller is to reduce the error between the desired command and output. We propose the model-following time delay controller with modified error feedback controller. This was applied to follow the desired reference model for the uncertain time-varying overhead crane. The model generates the damped-out swinging motion trajectory to suppress the swinging motion caused by the acceleration and the deceleration of crane transportation. The control performance was evaluated through simulations. The theoretical results indicate that this control method shows excellent performance to an overhead crane with the uncertain time-varying parameters.

• 한국지능시스템학회논문지
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• 제25권2호
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• pp.155-160
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• 2015

사람은 감정을 가진 동물이라고 말한다. 사람의 감정은 다양한 종류가 있으며 그 중 하나인 사랑은 사회학과 심리학에서 주된 관심사로 연구되어 왔다. 본 논문에서는 로미오와 줄리엣의 사랑 방정식에서 시간 지연 요소를 사랑에 대한 반응시간으로 가정하여 반영하였다. 줄리엣에만 시간지연이 있는 경우, 로미오에만 시간지연이 있는 경우, 로미오와 줄리엣 모두에 시간지연이 있는 경우를 고려하여 이들의 거동을 시계열과 위상 공간으로 나타내고 이들 사이의 차이를 분석하였다.

• 대한핵의학회지
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• 제30권4호
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• pp.493-501
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• 1996

관상동맥 질환으로 관동맥 우회로 수술을 받은 환자에서 수술 전에 휴식-24시간 지연 영상을 얻어 휴식기 T1-201 섭취와 24시간 후의 재분포 여부를 평가하여 수술 후 심근벽 운동이 호전되었는지 여부와 비교하여 다음과 같은 결과를 얻었다. 1) 대상 환자 17명에서 휴식기 관류가 정상이 아닌 분절이 56분절이었으며 이 중 조금 감소된 분절이 31 분절, 감소가 심한 분절이 14분절, 결손인 분절이 11 분절이었다. 24시간 지연 영상에서 재분포를 보인 분절이 19분절, 재분포가 없었던 분절이 37분절이었다. 2) 56분절 중 수술 후에 호전된 분절이 34분절(61%), 호전되지 않은 분절이 22분절(39%)이었다. 호전된 분절을 생존심근 호전되지 않은 심근을 비생존 심근으로 보았다. 3) 휴식기 T1-201 섭취가 조금 감소한 경우 수술 후 심근벽 운동이 호전될 가능성이 컸다. 4) 휴식기 T1-201섭취에 비해 지연기에 재분포된 19개 분절 중 74%에서 심근벽 운동이 호전되었다. 재분포가 없었던 37개 분절도 54%가 호전되었다. 5) 휴식기 관류감소가 심하지 않거나 재분포되었을 때 생존심근을 76%에서 예측할 수 있었다. 휴식기 관류감소가 심하며 동시에 지연기에 재분포되지 않은 경우 비생존심근임을 85%에서 예측할 수 있었다. 관동맥 우회로 수술 전에 얻은 휴식-24시간 지연 T1-201 SPECT로 휴식기 T1-201 섭취 정도와 지연기 재분포 여부를 관찰함으로써 수술 후 심근벽 운동의 호전 여부를 예측할 수 있었다. 휴식 T1-201/디피리다몰 부하 Tc-99m-MIBI/지연 T1-201 SPECT 검사로 관상동맥 질환을 진단할 수 있을 뿐 아니라 생존심근을 찾는 데 바람직한 검사로 생각하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.559-571
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• 2008

Platform Screen Door(PSD) has been installed and operated at seoul subway line $1\sim4$ in the manual train operation mode(ATS/ATC) by SeoulMetro since 2005. SeoulMetro uses the wireless (RF) communication system and the train door detection system for the link between the train and PSD doors opening/closing motion in the manual train operation mode. For the convenience and safety of passengers, the train doors and the PSD doors opening/closing shall be synchronized as much as possible. In ATO(Automatic Train Operation) mode which provides the interface between train control system and PSD system, ATO signaling system makes the train doors and PSD doors open/close command signals systematically, so PSD doors can be opened/closed almost simultaneously with the train doors. But, in the manual train control(ATS/ATC) mode, PSD system needs to detect the train doors open/close operation and make PSD open/close command signals to actuate PSD doors. These PSD open/close commanding process cause time delay of PSD doors opening/closing motion in response to the train doors opening/closing motion. Sometimes the response delay time can be over 1 second, which is not proper to operate PSD, and need to be reduced This paper presents the reduction method of the PSD response delay time to improve the convenience and safety of passengers.

• 산업기술연구
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• 제21권B호
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• pp.91-98
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• 2001

In this paper, center detection and motion analysis of a moving object are studied. Kohonen's self-organizing neural network models are used for the moving objects tracking and time delay neural networks are used for dynamic characteristic analysis. Instead of objects brightness, neuron projections by Kohonen Networks are used. The motion of target objects can be analyzed by using the differential neuron image between the two projections. The differential neuron image which is made by two consecutive neuron projections is used for center detection and moving objects tracking. The two differential neuron images which are made by three consecutive neuron projections are used for the moving trajectory estimation. It is possible to distinguish 8 directions of a moving trajectory with two frames and 16 directions with three frames.

• 한국소음진동공학회논문집
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• 제26권5호
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• pp.546-551
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• 2016

The objective of this study is to investigate the response delays between piezo-stack actuator and the displacement magnifier of jetting dispenser and to reduce its falling time in terms of displacement optimization. The dispenser is driven by the dual piezo-stack actuators with a hinge lever mechanism to precisely control flow rate of the working fluid (3000 cP). It is commonly found that piezo actuator-driven jetting dispensers involving viscous working fluids have displacement optimization problem for ideal performance. The response delay of the system is caused by the phenomenon that the displacement magnifier cannot exactly follow the motion of the piezo actuators. The response delay may lower the performance of the system due to the inaccurate discharge of working fluid or even damages to the system itself due to inharmonious motion of piezo actuators with lever system. To reduce its response delay, a new displacement profile obtained from displacement optimization is suggested; its performance is tested through finite element analysis; and experiments are carried out to verify the performance of the obtained displacement profile.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.215-218
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• 1998

In this paper, we design the $H_{\infty}$ controllers satisfying robust stability and performance for underwater vehicle. The underwater vehicle has computations delay time and input delay. In addition, there exist parameter uncertainties by the roll motion coefficient error, buoyance error, and gravity error. We design the $H_{\infty}$ controllers using model-matching method and check the performance of the proposed controller by nonlinear simulation which includes time delay model, sensor error model, and actuator model.