• Title/Summary/Keyword: internal control method

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Improvement of Active Contour Model for Detection of Pulmonary Region in Medical Image (의학 영상에서 폐 영역 검출을 위한 Active Contour 모델 개선)

  • Kwon Y. J.;Won C. H.;Park H. J.;Lee J. H.;Lee S. H.;Cho J. H.
    • Journal of Korea Multimedia Society
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    • v.8 no.3
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    • pp.336-344
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    • 2005
  • In this paper, we extracted the contour of lung parenchyma on EBT images with the improved active contour model. The objects boundary in conventional active contour model can be extracted by controlling internal energy and external energy as energy minimizing form. However, there are a number of problems such as initialization and the poor convergence about concave part. Expecially, contour can not enter the concave region by discouraging characteristic about stretching and bending in internal energy. We controlled internal energy by moving local perpendicular bisector point of each control point in the contour and implemented the object boundary by minimizing energy with external energy The convergence of concave part could be efficiently implemented toward lung parenchyma region by this internal energy and both lung images for initial contour could also be detected by multi-detection method. We were sure this method could be applied detection of lung parenchyma region in medical image.

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A Study on the Validity of DSOM According to Alcohol Intake (알코올 섭취량에 따른 한의변증설문(DSOM)의 타당성에 대한 연구)

  • Hong, Sang-Hoon;Kim, Jung-Eun;Kim, Sung-Hwan;Park, Sang-Eun;Hong, Su-Hvun;Kang, Chang-Wan;Lee, In-Sun
    • The Journal of Internal Korean Medicine
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    • v.30 no.1
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    • pp.119-128
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    • 2009
  • Purpose : This study was conducted to find the possibility of DSOM (Diagnosis System of Oriental Medicine) as a diagnostic method according to alcohol intake. Method : 49 men who drink alcohol over 40g per day and whose AUDIT scores were over 12 were allocated to the drinker group. 30 men who do not drink alcohol at all were allocated to the control (non-drinker) group. The study period was from June 15, 2006 to September 30, 2008. All of both groups were analyzed using DSOM. Result : There were some differences between the drinker group and the non-drinker group in stagnation of Ki(氣滯), deficiency of Yin(陰虛), insufficiency of Yang(陽虛), heat syndrome(熱), dryness (燥), and lung(肺). A group whose gamma-GTP is over twice the normal condition shows meaningful difference in stagnation of Ki(氣滯), heat syndrome(熱), dryness(燥), and insufficiency of Yang(陽虛). Conclusion : We found out that DSOM can be a diagnostic method on alcoholic liver disease patients. However, other studies to supplement it should be continued.

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A fuzzy-logic controller for a differential-drive mobile robot (이동로봇을 위한 퍼지로직 제어기)

  • 박영민;김대영;한상완;홍석교
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.532-535
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    • 1997
  • This paper describes the design of a fuzzy-logic controller for a differential-drive mobile robots. This controller uses absolute position information to modify control parameters to compensate the orientation error. CC-Control method is compensated for the internal error by wheel encoders and the fuzzy-logic control provides compensation for external errors. The validities of the proposed scheme is evaluated using simulation.

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An active vibration control system with state feedback

  • Iwai, Zenta;Ishitobi, Mitsuaki;Hino, Mitsushi
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.755-759
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    • 1989
  • This paper considers an active vibration control system based on pole placement incorporating the internal model principle when the system is subjected to disturbances which are generated by a linear dynamical system. Experimental results are presented which show the effectiveness of the method when the system is excited by a sine wave disturbance and system parameters are knwon. An adaptive control design is also discussed.

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A Force Reflecting Position Control for Teleoperation Systems with Signal Transmission Time Delay (신호전송 시간지연을 갖는 원격조작시스템의 힘반영 위치제어)

  • 안성호;진재현;박병석;윤지섭
    • Proceedings of the IEEK Conference
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    • 2002.06e
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    • pp.157-160
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    • 2002
  • When the teleoperation system has a signal transmission time delay between slave system and control system, the position tracking performance of the slave system and system stability are likely to be deteriorated. This paper proposes a force reflecting position control scheme for teleoperation system with signal transmission time delay. The proposed scheme not only satisfy the system internal stability but also improves the position tracking performance with disturbance rejection capability. The simulation results show that the proposed control method provides excellent performances.

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Improvement of the Robustness and Simulatins of Adaptive Control (적응 제어기의 강인성 개선 및 시뮬레이션)

  • 허명준;김국헌;양흥석
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.38 no.4
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    • pp.298-306
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    • 1989
  • Robustness of adaptive pole-placement control against unmodeled dynamics is proved. This proof is done by showing that the sufficient condition for robustness, conic condition and stability of a specific operator, is satisfied for a larger set of unmodeled dynamics. The simulation results show the proposed method is quite powerful. And the difference between the concept of the pseudoplant control and the known internal model control is shown by the closed loop analysis.

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Design of a robust gauge controller for a single-stand cold rolling mill (단일 스탠드 냉간 압연 공정을 위한 견실한 두께 제어기의 설계)

  • An, Hyeon-Sik;Yun, Tae-Ung;Kim, Gwang-Bae
    • Journal of Institute of Control, Robotics and Systems
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    • v.2 no.3
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    • pp.134-141
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    • 1996
  • In this paper, we formulate the mathematical model for a single-stand rolling mill and design control systems for the thickness control at the exit of roll stand and for the tension control of the strip in the process. We propose a thickness controller based on the Internal Model Control structure which can be an effective application when the frequency components of the thickness deviation of the entry strip are known and, show how it can be appropriately combined with BISRA AGC method for a precise thickness control while maintaining the robustness against the modeling error of the mill modulus. It is illustrated by simulations that the proposed thickness control method gives better performance than existing methods and has the robustness against the modeling error of the mill modulus as well.

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Design of a synchronization controller for non-rail mobile rack using repetitive control method (반복제어기법을 이용한 무궤도 이동랙 동기화제어기 설계)

  • Kim, Hwan-Seong;Park, Jin;Ha, Yun-Su
    • Journal of Advanced Marine Engineering and Technology
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    • v.40 no.6
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    • pp.527-534
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    • 2016
  • The non-rail mobile rack, which is used for cargo storage, can improve the storage capacities of logistics centers. Furthermore, it has the advantage that it can be used in traditional logistics centers without making any changes or renovation, such as installing rails. However, when the rack is operated by separated drive actuators mounted on the left and the right wheels, precise position control of the wheels is necessary even if the unbalanced cargo weight on the rack would affect the control. Therefore, internal synchronization control for position tracking between the left and right wheels on the non-rail mobile rack is necessary in this study. In addition, external synchronization control for realizing the same straight movements between mobile racks is necessary. For the internal and the external synchronization control, we propose a synchronization control algorithm based on the repetitive control theory. An internal synchronization control algorithm with repetitive control theory requires the application of the robust servo control method owing to parameter variations. In this case, we can set up the gains for the robust servo control system by considering the cargo variations on the mobile rack. Furthermore, for developing the external synchronization control algorithm, we use a double repetitive control system to perform synchronization control between mobile racks. The efficiency of the proposed control algorithm will be verified by simulation and experimental results. The proposed algorithm can be easily applied in the industry.

Effects of Astragali Radix on Neutropenia Caused by Cyclophosphamide (황기 추출물의 전투여(前投與)가 Cyclophosphamide로 유발된 호중구 감소증에 미치는 영향)

  • Jeong, Seung-Min;Ko, Seung-Gyu;Go, Ho-Yeon;Choi, You-Kyung;Kim, Dong-Woo;Park, Jong-Hyung;Jun, Chan-Yong
    • The Journal of Internal Korean Medicine
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    • v.28 no.1
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    • pp.1-11
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    • 2007
  • Objective : To study effects of Astragali radix on relieving neutropenia caused by cyclophosphamide. Method : We administered Astragali radixextracts for 7 days before injecting cyclophosphamide 200mg/kg to mice subcutaneously to cause neutropenia. The control group wasn't administered Astragali radix. One test group was administered Astragali radix extracts 500mg/kg and the other was administered 1000mg/kg. We observed WBC, neutrophil, lymphocyte, platelet, RBC, GOT, GPT, BUN, and creatine. Result : WBC, RBC, lymphocyte, neutrophil, and platelet improved more in mice administered Astragali radix extracts. Moreover, the 1000mg/kg group was more affected than the 500mg/kg group generally. GOT, GPT, BUN, and creatine weren't changed significantly compared with the control group. Conclusion : It is shown that Astragali radix extracts can relieve neutropenia induced by cyclophosphamide and we conclude that Astragali radix will be useful for cancer treatment.

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A Comparison of Reliability and Anterior Glide Distance of Humerus Head of Passive Shoulder Internal Rotation Range of Motion Measurement Methods (어깨관절의 수동적 내회전 관절 가동범위의 측정 방법에 따른 신뢰도와 상완골두의 전방 활주 거리 비교)

  • Kim, Hyun-Sook;Lee, Won-Hwee;Choung, Sung-Dae
    • Physical Therapy Korea
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    • v.17 no.3
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    • pp.1-10
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    • 2010
  • The purpose of this study was to measure intra-rater and inter-rater reliability and range of motion for measurement of passive shoulder internal rotation range of motion and to compare anterior glide distance of humeral head in three methods. Fifty healthy subjects and fifty patients with shoulder musculoskeletal pain were recruited for this study. The subjects' passive shoulder internal rotation range of motion was measured by visual estimation, manual stabilization, and pressure biofeedback unit methods. In two trials, measurements were performed on each subject by two examiners. Intraclass correlation coefficient (ICC(3,1)) was used to determine the reliability of each measurement. The intra-rater reliability of the three methods was excellent (ICC=.77~.93) in both groups. The inter-rater reliability of the visual estimation method was poor (ICC=.20, .29), the manual scapular stabilization method was poor and fair (ICC=.09, .50), and the pressure biofeedback unit method was excellent (ICC .86, .75) in the experimental and control groups. In the experimental group, the difference of examined range of motion by each examiner was significant in the visual estimation method and manual scapular stabilization method, but there was an insignificant difference between the groups is the pressure biofeedback unit method. This result suggests that the intra-rater and inter-rater reliability of a pressure biofeedback unit was better than the other methods. The difference in distance of the anterior glide of humeral head was insignificant among all the methods. The pressure biofeedback unit method was the most reliable method, so it is proposed to be a new and reliable method to measure internal rotation range of motion.