• 전기전자학회논문지
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• 제13권3호
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• pp.32-38
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• 2009

Ultrasonic motor (USM) is a new type motor which is driven by the ultrasonic vibration of piezoelectric elements. It possess many useful features that electromagnetic motors do not have, such as low speed and high torque. However, ultrasonic motor has heavy nonlinear speed characteristics and is sensitive to the change of drive conditions. In order to solve these problems, we present a smooth position control scheme for ultrasonic motor using fuzzy logic control with human expertise and without the need of any precise mathematical model. A "smooth operation" consideration is included when constructing the fuzzy rule base in order to achieve a most smooth response. An experimental position control system is constructed to show the effectiveness of the proposed control scheme.

• International Journal of CAD/CAM
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• 제7권1호
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• pp.11-20
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• 2007

A topology optimization methodology, named "smooth boundary topology optimization," is proposed to overcome the shortcomings of cell-based methods. Material boundary is represented by B-spline curves and their control points are considered as design variables. The design is improved by either creating a hole or moving control points. To determine which is more beneficial, a selection criterion is defined. Once determined to create a hole, it is represented by a new B-spline and recognized as a new boundary. Because the proposed method deals with the control points of B-spline as design variables, their total number is much smaller than cell-based methods and it ensures smooth boundaries. Differences between our method and level set method are also discussed. It is shown that our method is a natural way of obtaining smooth boundary topology design effectively combining computer graphics technique and design sensitivity analysis.

• 터널과지하공간
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• 제21권3호
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• pp.235-243
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• 2011

본 연구에서는 SB발파에서 평활한 최종파단면과 발파손상영역을 제어하고, 동시에 발파진동을 제어하기 위한 목적으로 무장약 균열 유도공을 이용한 제어발파기법을 제안하였다. 무장약 균열유도공의 파단면 제어 유효성을 검토하기 위하여 일반 SB발파와 무장약 균열 유도공 적용한 SB발파에서 암반 내 발생하는 파괴과정을 수치해석법으로 모사하여 파단면을 분석하였다. 제발효과를 높이기 위하여 도폭선에 의한 기폭을 고려하였으며, 무장약 균열 유도공을 중심으로 양쪽에 장약공이 설치된 일자유면 발파로 가정하여 암반의 파괴과정해석을 수행하여 SB발파에서 무장약 균열 유도공에 의한 파단면 형성 기구를 고찰하였다. 결과적으로, 공간격이 40cm 이하에서 무장약 균열 유도공을 사용한 경우가 낮은 파단면 거칠기를 보여 파단면 제어 효과가 있음을 입증 하였다.

• Journal of Mechanical Science and Technology
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• 제14권5호
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• pp.499-507
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• 2000

Smooth shift is one of the key issues in automatic power transmission control systems. However, the torque sensors are too expensive to be used in shift controllers on production vehicles. In order to provide a basic strategy for smooth shifting by using RPM sensors only and in order to accomplish the shift within a designated time, this paper studies detailed characteristics of the smooth shift for clutch-to-clutch shift mechanism. A desired trajectory of slip speed is proposed for smooth acceleration shift defined in this paper. Also the clutch torque needed to achieve this trajectory is derived, and it may be used as a open loop shift control law.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.297-300
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• 1997

This paper uses genetic algorithm (GA) for optimal control. GA can find optimal control profile, but the profile may be oscillating feature. To make profile smooth, fuzzy genetic algorithm (FGA) is proposed. GA with fuzzy logic techniques for optimal control can make optimal control profile smooth. We describe the Fuzzy Genetic Algorithm that uses a fuzzy knowledge based system to control GA search. Result from the simulation example shows that GA can find optimal control profile and FGA makes a performance improvement over a simple GA.

• 대한한방내과학회지
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• 제15권2호
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• pp.240-248
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• 1994

These studies were carried out to investigate the effects of Macmundongtang extract on the inhibitory contractile action of acetylcholine in control rat. The results of these studies were as follows: 1. Contractile force of acetylcholine from tracheal smooth muscle in control rat was significantly inhibited by Macmundongtang. 2. Inhibition contractile action of acetylcholine pretreated ACH $ED_{50}$ in control rat was significantly changed. 3. Dose-response of acetylcholine pretreated Macmundongtang in control rat was not significant. 4. Inhibitory contractile action of acetylcholine pretreated propranolol in control rat was not significantly changed by Macmundongtang. 5. Inhibitory contractile action of acetylcholine pretreated methylene blue in control rat was significantly changed. 6. Contractile force of acetylcholine pretreated indomethacin from trachea smooth muscle in control rat was not significantly inhibited by Macmundongtang.

• 제어로봇시스템학회논문지
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• 제12권7호
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• pp.671-678
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• 2006

This article proposes a smooth path generation and time scheduling method for general tasks defined by non-smooth path segments in industrial robotic applications. This method utilizes a simple 3rd order polynomial function for smooth interpolation between non-smooth path segments, so that entire task can effectively maintain constant line speed of operation. A predictor-corrector type numerical mapping technique, which correlates time based speed profile to the smoothed path in Cartesian space, is also provided. Finally simulation results show the feasibility of the proposed algorithm.

• 대한한방내과학회지
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• 제15권1호
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• pp.227-237
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• 1994

These studies were carried out to investigate the effects of Ohotang water extract on the inhibitory contractile action of acetylcholine in control rat. The results of these were as follows; 1. Contractile force of acetylcholine from trachea smooth muscle in control rat was significantly inhibited by Ohotang. 2. Dose-response of acetylcholine pretreated Ohotang in control rat was significantly inhibited. 3. Inhibitory contractile action of acetylcholine pretreated propranolol in control rat was significantly inhibited by Ohotang. 4. Contractile force of acetylcholine pretreated indomethacin from trachea smooth muscle in control rat was not significantly changed. 5. Inhibitory contractile action of acetylcholine pretreated methylene blue in control rat was not significantly changed.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2003년도 학술대회 논문집
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• pp.193-195
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• 2003

In superconductor power systems, a quench detector can misrecognize oscillation about current or voltage control as a quench. So, for the correct detection of a quench, it seems need to guarantee a smooth control of current or voltage. In this paper, we have studied a control function and control parameter for smooth control of current or voltage.

• 대한한방내과학회지
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• 제14권2호
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• pp.1-19
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• 1993

This study was carried out to investigate the effects of Gooboeum extract on the inhibitory contractile action of acetylcholine in the control and sensitized rat. The results were obtained as follows: 1. The acetylcholine contractile force of the trachea smooth muscle with epithelium was significantly relaxed by Gooboeum. 2. Dose-response of acetylcholine from the trachea smooth muscle pretreated Gooboeum was not changed. 3. Effect of Gooboeum on the inhibitory contractile action of trachea smooth muscle pretreated propranolol was not significantly inhibited. 4. The inhibitory contractile action of acetylcholine of trachea smooth muscle pretreated indomethacin was not significantly changed by Gooboeum. 5. Effects of Gooboeum extract on the inhibitory contractile action of acetylcholine of trachea smooth muscle pretreated methylene blue was not significant. 6. The contractile force of acetylcholine of the trachea smooth muscle without epithelium was significantly inhibited by Gooboeum. 7. Dose-response of acetylcholine of the trachea smooth muscle pretreated Gooboeum was not significant. 8. Effects of Gooboeum extract on the inhibitory contractile action of acetylcholine of the trachea smooth muscle pretreated propranolol was significantly inhibited. 9. Effects of Gooboeum extract on the inhibitory contractile action of acetylcholine of the trachea smooth muscle pretreated indomethacin decreased. 10. Effects of Gooboeum extract on the inhibitory contractile action of acetylcholine of the trachea smooth muscle pretreated methylene blue was not significant.