• Title/Summary/Keyword: Control Technique

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A Technique and software of analysis and control for measurement process

  • Zhao, Fengyu;Xu, Jichao;Bergman, Bo
    • International Journal of Quality Innovation
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    • v.1 no.1
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    • pp.97-105
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    • 2000
  • In this paper, a two-section method for measuring is introduced and the variation sources of measurement process are analysed. Measuring is a special process in general process. Various variation source must be firstly decomposed so that the statistical distribution law of measuring process can be established, and then implement monitoring control of the measuring process. A special method to obtain the measuring variation is discussed, and a monitoring control technique for measuring process is studied based statistical distribution. Towards the end, we briefly introduce software design for the analysis and control of a measurement process.

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A Constant Air Volume Rate Control of Blower Using V/F Control (V/F제어를 이용한 송풍기의 일정한 공기압제어)

  • Jeong, Jong-Ho;Mun, Je-Yeon;Yun, Seo-Jin;Lee, Eun-Woong
    • Proceedings of the KIEE Conference
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    • 1998.11a
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    • pp.100-102
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    • 1998
  • This paper presents technique to control blower at constant air volume rate using V/F Control. Especially, this control method have not pressure sensors to measure because of using torque-speed relation based on the fan laws. Therefore, this technique is very simple and practical.

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Optimization of LQR method for the active control of seismically excited structures

  • Moghaddasie, Behrang;Jalaeefar, Ali
    • Smart Structures and Systems
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    • v.23 no.3
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    • pp.243-261
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    • 2019
  • This paper introduces an appropriate technique to estimate the weighting matrices used in the linear quadratic regulator (LQR) method for active structural control. For this purpose, a parameter is defined to regulate the relationship between the structural energy and control force. The optimum value of the regulating parameter, is determined for single degree of freedom (SDOF) systems under seismic excitations. In addition, the suggested technique is generalized for multiple degrees of freedom (MDOF) active control systems. Numerical examples demonstrate the robustness of the proposed method for controlled buildings under a wide range of seismic excitations.

Management of the Access Control for a WebDAV-based Collaborative System (웹데브 기반 협업시스템에서의 접근 제어 관리)

  • Kim, Seong-Hune;Lee, Hong-Chang;Lee, Myung-Joon;Park, Yang-Su
    • Journal of Internet Computing and Services
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    • v.11 no.1
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    • pp.167-181
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    • 2010
  • WebDAV is an IETF standard protocol which supports asynchronous collaborative authoring on the Web. The WebDAV Access Control Protocol provides various methods of controlling the resources on a WebDAV server and their properties, helping high-level group activities to be performed through the WebDAV server. In this paper, to provide high level collaboration, we introduce a technique for managing access control over WebDAV resources through the WebDAV Access Control Protocol and describe the development of an access control manager for the CoSlide Collaborative system based on the technique. To provide users with the access control features in an easily understandable manner, the developed technique presents the privileges for performing WebDAV methods instead of the standard privileges in the WebDAV Access Control Protocol. In addition, we present the facility for detecting conflicts between new access privileges on resources and old access privileges on them. We applied the method-based access control management technique to the CoSlide collaborative system. The developed access control manager enables us to create group workspaces with flexible access control strategies for group members and resources.

A Novel PWM Swiching Technique for Conducted EMI Reduction in Vector-Controlled Induction Motor Drive (유도전동기 벡터제어 시스템의 EMI저감을 위한 새로운 PWM기법)

  • Bae, W.R.;Lee, W.C.;Yu, J.S.;Kim, L.H.;Hahm, N.K.;Won, C.Y.
    • Proceedings of the KIPE Conference
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    • 2005.07a
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    • pp.321-324
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    • 2005
  • This paper describes the application of newly developed conducted EMI reduction technique of SVPWM in induction motor drive. The newly developed common mode voltage reduction SVPWM technique doesn't any zero-voltage vector states for inverter control. Hence it can restrict the common mode voltage better than conventional PWM technique. The proposed technique is verified through simulation and experimental results. And by applying vector-controled system, the proposed technique have superior ability of reducing EMI and equal control performance comparing conventional SVPWM technique.

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A Study on Change of Soil-Water Retention Curve with Different Net Confining Pressures and Porosities using a Suction-Saturation Control Technique (흡입력-포화도 조절 기법을 이용한 불포화토의 함수특성곡선에 미치는 간극비 및 순구속압력의 영향 연구)

  • Lee, Joon-Yong;Yu, Chan
    • Journal of The Korean Society of Agricultural Engineers
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    • v.54 no.4
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    • pp.93-103
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    • 2012
  • A suction-saturation control technique based on flow pump system was developed to investigate hydraulic properties in unsaturated soils. The flow pump system is designed based on the principle of the axis-translation technique and triaxial equipment, and gives the suction-time and suction-saturation curves, the primary relationship needed for interpreting the response of unsaturated soils and link between theory and the material properties in unsaturated soil mechanics. Using the suction-saturation control technique, suction-time relationship and soil-water retention curve (SWRC) during hydraulic hysteresis were investigated with different net confining pressures and porosities. Three types of soils-two sands and a silt were used in this paper. This paper showed the effect of the hysteresis on the SWRC due to different net confining pressures and porosities. This means that a careful decision must be made as to which condition is to be modeled, since the delicate difference of the conditions in physical modeling can cause the different experimental output.

The Imaging Anatomical Consideration about Effects of Respiratory Disease on the Breath Control and Resonance in Vocal Technique (발성기법중 호흡기 질환이 호흡조절과 공명에 미치는 영향에 관한 영상해부학적 고찰)

  • Lee, Dong-Myoung
    • Journal of radiological science and technology
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    • v.24 no.2
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    • pp.41-47
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    • 2001
  • This study was undertaken to examine the differences between normal vocal technique and abnormal vocal technique because of diseases in respiratory system(emphysema). The breath control for vocalizing with diaphragmatic respiration must be sustained clearly. But if there is an abnormality in lung(emphysema), it is not sustained to hold diaphragmatic respiration when we sing. In order to examine the differences of the width in diaphragmatic respiration among professional singer's case, non professional case and the case of respiratory disturbance, Shimadzu X-ray remote control TV system was used. The results obtained were summerized as follows: When we vocalize, breath control is very important not only to sustain a resonance but also to form focus for being scattered to cranial resonance. We must know the differences between normal and abnormal diaphrogmatic respiration in order to teach vocal technique right. professional singer's vocal technique with Piaphragmatic respiration was better than that compared with non professional case and respiratory disturbance. Non professional case was very similar to the case of respiratory disturvance in diaphragmatic respiration until 10 sec. after full inhalation, but diaphragmatic respiration in the case of 20 sec. after full inhalation was very different.

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A Simple AMC Technique using ARQ for a MIMO-OFDM System based on IEEE 802.11a WLANs (IEEE 802.11a WLAN 기반 MIMO-OFDM 시스템에서 ARQ를 이용한 간단한 적응변조 기법)

  • 유승연;김경연;이충용;홍대식;박현철
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.41 no.7
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    • pp.1-8
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    • 2004
  • A simple AMC (Adaptive Modulation and Coding) technique using ARQ (Automatic Repeat Request) for a MIMO (Multiple Input Multiple Output) system is proposed which does not require the additional feedback. In addition, the proposed AMC technique is different from the conventional technique in the aspect of considering the MCS (Modulation and Coding Scheme) level from the previous packet. The proposed technique can discard fewer amounts of unsuitable packets than the conventional technique. In the proposed system not only same rate control method for transmit antennas but also individual rate control method can be applied. The performance of the proposed technique is verified under a MIMO-OFDM (Orthogonal Frequency Division Multiplexing) system based on WLAN (Wireless Local Area Network), IEEE 802.11a. The results of the computer simulation show that a MIMO system with the proposed technique achieves higher throughput than one with a fixed transmission rate.

Changes of Maximum Inspiratory Pressure, Maximum Expiratory Pressure, Back Mobility by Diaphragm Stretching Technique in Patients with Low Back Pain (가로막 스트레칭 기법에 의한 허리통증 환자의 최대들숨압력과 최대날숨압력, 허리 가동성 변화 )

  • In-young Kong
    • PNF and Movement
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    • v.21 no.2
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    • pp.185-192
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    • 2023
  • Purpose: This study aimed to confirm the effectiveness of the diaphragm stretching technique as a treatment method for low back pain by evaluating maximum inspiratory pressure, maximum expiratory pressure, and changes in back mobility in patients with low back pain. Methods: Thirty-four patients with low back pain were randomly divided into two groups: an experimental group and a control group. The diaphragm stretching technique was conducted in the experimental group, and the placebo intervention was conducted in the control group. The diaphragm stretching technique was conducted once, maintaining tension for 7 min. The placebo intervention was conducted in the same position as the diaphragm stretching technique, but with only light contact maintained without pressure. Maximum inspiratory pressure, maximum expiratory pressure, and back mobility were measured before and after the intervention, and the changes were compared and analyzed. A paired sample t-test was used to compare measurements within the group before and after the intervention. An independent t-test was used to compare the experimental and control groups. Statistical significance (α) was set at 0.05. Results: In the experimental group, maximum inspiratory pressure, maximum expiratory pressure, and back mobility increased significantly after the intervention (p < 0.05). However, there was no significant difference in the changes in all areas of the control (p > 0.05). As a result of comparative analysis of changes before and after the intervention, there were significant differences in maximum inspiratory pressure, maximum expiratory pressure, and back mobility only in the experimental group (p < 0.05). Conclusion: The diaphragm stretching technique improved maximum inspiratory pressure, maximum expiratory pressure, and back mobility compared to the placebo intervention. Therefore, the diaphragm stretching technique can be recommended as a physical therapy intervention to improve pain in patients with LBP.

Vibration Suppression Control for a Geared Mechanical System;Simulation Study on Vibration Suppression Effects Using a Model-Based Control with a Rotational Speed Sensor

  • Itoh, Masahiko
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.694-699
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    • 2005
  • This paper deals with a control technique of eliminating the transient vibration of a geared mechanical system. This technique is based on a model-based control with a rotational speed sensor in order to establish the damping effect at the driven machine part. A rotational speed sensor is installed in a driven gear, namely a bull gear. A control model is composed of a reduced-order mechanical part expressed as a transfer function between the rotational speed of the motor and that of the bull gear. This control model estimates a load speed after the rotational speed of the bull gear is acted on the transfer function. The difference between the estimated load speed and the motor speed is calculated dynamically and it is added to the velocity command to suppress the transient vibration generated at the load. This control technique is applied to a dies driving spindle of a form rolling machine. In this paper, the performance of this control method is examined by simulations. The settling time of the residual vibration generated at the loading inertia can be shortened down to about 1/2 of the uncompensated vibration level.

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