• Title/Summary/Keyword: control effect

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The Effect of Estimated Control Limits

  • JaiWook Baik;TaiYon Won
    • Communications for Statistical Applications and Methods
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    • v.5 no.3
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    • pp.645-657
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    • 1998
  • During the start-up of a process or in a job-shop environment conventional use of control charts may lead to erroneous results due to the limited number of subgroups used for the construction of control limits. This article considers the effect of using estimated control limits based on a limited number of subgroups. Especially we investigate the performance of $\overline{X}$ and R control charts when the data are independent, and X control chart when the data are serially correlated in terms of average run length(ARL) and standard deviation run length(SDRL) using simulation. It is found that the ARL and SDRL get larger as the number of subgroups used for the construction of the chart becomes smaller.

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Multi-dimensional seismic response control of offshore platform structures with viscoelastic dampers (I-Theoretical analysis)

  • He, Xiao-Yu;Li, Hong-Nan;Zhang, Jun
    • Structural Monitoring and Maintenance
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    • v.3 no.2
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    • pp.157-174
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    • 2016
  • Based on classical viscoelastic damper, a brand-new damper is designed by the change of simple construction to implement vibration control for both translational vibration and rotational vibration simultaneously. Theoretic analysis has been carried out on the restoring force model and the control parameters. Two improved models are presented to obtain high simulation precision. The influence of the size, shape of the viscoelastic material, the ambient temperature and the response frequency on the vibration control effect is analyzed. The numerical results show that the new type viscoelastic damper is capable of mitigating the multi-dimensional seismic response of offshore platform and the response control effect has complicated relations with aforementioned related factors.

Design for Pressurizing System about Vestibule by Stack Effect & Engineering Analysis - Focused on Case Study - (굴뚝효과와 공학적분석에 의한 부속실 가압시스템 설계 - 사례를 중심으로 -)

  • Kim, Yong-Kwang
    • Fire Science and Engineering
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    • v.23 no.4
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    • pp.145-153
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    • 2009
  • We are generally applicate smoke control only vestibule about special escape staircase, it is one of some smoke control model of NFSC 501A. But there are some point at issue in this system. The smoke control system on supervision field of writer is smoke control only vestibule same as the other resemble field. Writer studied in the concrete to find a solution at this issue, and derived a conclusion the most reasonable system on the field is "same time smoke control for staircase and vestibule" by the engineering analysis considering stack effect.

Learning Control of Pipe Cutting Robot with Magnetic Binder (자석식 자동 파이프 절단기를 위한 학습제어기)

  • Kim Gook-Hwan;Lee Sung-Whan;Rhim Sung-Soo
    • Journal of Institute of Control, Robotics and Systems
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    • v.12 no.10
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    • pp.1029-1034
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    • 2006
  • In this paper, the tracking control of an automatic pipe cutting robot, called APCROM, with a magnetic binder is studied. Using magnetic force APCROM, a wheeled robot, binds itself to the pipe and executes unmanned cutting process. The gravity effect on the movement of APCROM varies as it rotates around the pipe laid in the gravitational field. In addition to the varying gravity effect other types of nonlinear disturbances including backlash in the driving system and the slip between the wheels of APCROM and the pipe also cause degradation in the cutting process. To maintain a constant velocity and consistent cutting performance, the authors adopt a repetitive learning controller (MRLC), which learns the required effort to cancel the tracking errors. An angular-position estimation method based on the MEMS-type accelerometer is also used in conjunction with MRLC to compensate the tracking error caused by slip at the wheels. Experimental results verify the effectiveness of the proposed control scheme.

Effect of Recombinant Bovine Somatotropin (${\gamma}$ bST) Administration on bST Levels in Milk of Cows

  • Park, Jeongeun;Park, Myung-Ja;Jaeho Chin;Park, Jongsei;Kim, Jooho
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1995.04a
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    • pp.127-127
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    • 1995
  • The present study was conducted to examine the effect of recombinant bovine somatotropin(${\gamma}$ bST), which was administered to cow to promote milk production, on bST levels in milk. Fourteen cows were divided into two groups: 1) control cows received neither y bST nor vehicle, 2) treated cows were administered twice at two-week interval with 500mg ${\gamma}$ bST each cow by subcutaneous injection. Milk samples were taken on day 0 (prior to injection), day 7 (7 days after 1st injection), day 21 (7 days after 2nd injection) and day 35 (21 days after 2nd injection).

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Parental Behavior Control Recognized by Children and Its Effect on Children's Emotional Intelligence and Conflict Resolution Strategies in Peer Friendships (아동이 지각한 부모행동통제특성과 정서지능 및 친구 간 갈등해결전략)

  • Lee, Min Young;Kim, Kwang Woong;Cho, You Jin
    • Korean Journal of Child Studies
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    • v.27 no.6
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    • pp.149-165
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    • 2006
  • This study examined the relationships of parental behavior control recognized by children and its effect on children's emotional intelligence and conflict resolution strategies in their peer friendships. Subjects were 521 $5^{th}$, $6^{th}$ grade elementary school Children in seoul. Data were analyzed by Pearson's correlation, multiple regression and path analysis. Result showed that parents' control of children's behavior affected children's conflict resolution strategies in peer friendships and affected their emotional intelligence. Path analysis showed that control by parents, demand for maturity and clarity of communication directly affected compromising-integrating strategies. Parental control was affected directly by dominating strategies. Controlling behavior by demand of maturity, clarity of communication and nurture influenced compromising-integrating, avoidance and concession strategies of children's emotional intelligence.

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Nonlinear System Control using Neural Networks (신경 회로망을 이용한 비선형 계통의 제어)

  • Lee, Kee-Sang;Park, Tae-Geon;Lim, Jae-Hyung;Lee, Jung-Dong
    • Proceedings of the KIEE Conference
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    • 1994.11a
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    • pp.356-358
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    • 1994
  • In this paper, to alleviate the effect of approximation error and discontinuous variation of the controller parameters, the variable structure control scheme using neural networks is presented. In the proposed method, the variable structure control rules for each local linear models are designed to reject the effect of linearization error caused by linearization of the nonlinear system. And neural network infer approximate controller gains from combination of local linear control gains. The proposed control methods can be used to control nonlinear systems and it has robust characteristic against system parameter variations and external disturbances.

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Position and Vibration Control of a Spatial Redundant Flexible Manipulator by using Pseudo-inverse of Jacobian (유사 역행렬을 이용한 여유자유도 3차원 유연 매니퓰레이터의 위치 및 진동제어)

  • Kim, Jin-Su
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.12
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    • pp.66-72
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    • 2001
  • In this paper, by using pseudo-inverse matrix of the spatial redundant flexible manipulators, a position control method and its effect in vibration suppression was presented. Vibration suppression control was developed using lumped mass spring model of the flexible manipulators. With 2 elastic links and 7 rotory joint manipulator ADAM, (1)position control for no redundancy, and (2)position control for one redundant DOF(degree of freedom) were tested. The objective of this experiment is to show the effect of position control, using pseudo-inverse matrix. toward the improvement of operation, and at the same time, to reduce the vibration of the link and the magnitude of the joint torque.

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Effect of Control Valve Flow Rates Characteristics on the Performance of an Air Spring (제어밸브의 유량특성에 따른 에어스프링의 성능 변화)

  • Han, Seung Hun;Jang, Ji Seong;Ji, Sang Won
    • Journal of Drive and Control
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    • v.13 no.3
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    • pp.8-14
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    • 2016
  • This study describes the effect of the critical pressure ratio of a control valve on the performance of an air spring system composed of an air spring, auxiliary chamber, control valve and mass in order to suggest a more efficient design for an air spring system. The critical pressure ratio of the control valve is assumed to have a fixed value, but the critical pressure ratio of the control valve is known to have various values between 0.05 and 0.6, and the effect of the variation of the critical pressure ratio on the performance of the air spring system has not yet been reported. The analysis derives nonlinear and linear governing equations of the air spring system, including the critical pressure ratio of the control valve. This simulation study is presented to show that the impedance and transmissibility characteristics of the air spring system change due to variations in the critical pressure ratio of the control valve as well as its sonic conductance. As a result, the critical pressure ratio of the control valve should be maintained as large as possible to improve the vibration isolation characteristics of the air spring system.

Effect of Motor Control Training with Strengthening Exercises on Pain and Muscle Strength of Patients with Shoulder Impingement Syndrome

  • Bae, Youn-Hee;Lee, Gyu-Chang
    • The Journal of Korean Physical Therapy
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    • v.23 no.6
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    • pp.1-7
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    • 2011
  • Purpose: The purpose of this study was to investigate the effect of movement training based on motor control theory on pain and average power of muscles in patients with shoulder impingement syndrome and to develop more effective training methods. Methods: We studied 35 patients with shoulder impingement syndrome. Patients were randomly assigned to an experimental group or a control group according to the intervention. The therapeutic modalities such as superficial heat, deep heat, and electronic stimulus, and motor control training with strengthening exercises were applied to the experimental group and therapeutic modalities only were applied to the control group. All interventions were done 3 times a week for 4 weeks. Before the intervention and again after the 4 weeks, we measured pain utilizing a visual analog scale. We measured average power using isokinetic equipment. Results: After application of the intervention, pain significantly decreased in both the experimental group and the control group. There was a significant difference between the extent of the decrease between experimental and control groups. After the intervention, the average power between the two groups were significant at an angle of $60^{\circ}$/sec and $180^{\circ}$/sec for external rotator and internal rotator muscles. They also showed significant improvement in all variables post-intervention compared to pre-intervention. Conclusion: This study indicates that there is an effect in giving appropriate motor control training to patients with shoulder impingement syndrome. It is assumed that there will be a need for more surveys on various variables for motor control training from now on.