• Title/Summary/Keyword: Rising Time

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The Control of an Electrostrictive Polymer Actuator by Using Neural Network

  • Youn, Ji-Won;Jeon, Jae-Wook;Nam, Jae-Do;Park, Hyoukryeol;Kim, Hunmo
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.120.4-120
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    • 2002
  • $\textbullet$ In order to operate EP actuator, high voltage is applied to that. $\textbullet$ Our previous control algorithm for an EP actuator was PI method with constant gain. $\textbullet$ But this Control method is limitation such as rising time, steady-state error, and settling time. $\textbullet$ A neural network algorithm is proposed for improvement of performance. $\textbullet$ To do this, neural network algorithm changes the gain of PI control. $\textbullet$ In order to efficient drive EP actuator, the gain is changed at some point. $\textbullet$ Neural network method improve the performance of operation.

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Recovery Methods in Main Memory DBMS

  • Kim, Jeong-Joon;Kang, Jeong-Jin;Lee, Ki-Young
    • International journal of advanced smart convergence
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    • v.1 no.2
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    • pp.26-29
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    • 2012
  • Recently, to efficiently support the real-time requirements of RTLS( Real Time Location System) services, interest in the main memory DBMS is rising. In the main memory DBMS, because all data can be lost when the system failure happens, the recovery method is very important for the stability of the database. Especially, disk I/O in executing the log and the checkpoint becomes the bottleneck of letting down the total system performance. Therefore, it is urgently necessary to research about the recovery method to reduce disk I/O in the main memory DBMS. Therefore, In this paper, we analyzed existing log techniques and check point techniques and existing main memory DBMSs' recovery techniques for recovery techniques research for main memory DBMS.

A NEW METHOD OF LQ INTEGRAL CONTROL, FOR NONMINIMUM PHASE SYSTEMS

  • Kwon, Byung-Moon;Kwon, Oh-Kyu
    • 제어로봇시스템학회:학술대회논문집
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    • 1999.10a
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    • pp.79-82
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    • 1999
  • The right half plane (RHP) zeros may cause severe problems, such as undershoots, oscillations and time delay in the transient response of the systems. In this paper, we formulate a linear quadratic type problem to deal with the effects of the RHP zeros in the nonminimum phase systems. Based on the LQ formulation, this paper shows the trade-off relation between undershoot and rising time performances in nonminimum phase systems by using a new performance index which consists of new state and tracking error. And performances of the proposed method are shown via computer simulations.

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Effects of MWCNT Nucleating Agent on the Formation Reaction of Rigid Polyurethane Foams

  • Ahn, WonSool;Lee, Joon-Man
    • Elastomers and Composites
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    • v.50 no.1
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    • pp.13-17
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    • 2015
  • A study of the effects of MWCNT as a nucleating agent on the formation reactions of the rigid polyurethane foams (RPUFs) was carried out. Sample PUFs, formulated with grease-type master batch of MWCNT/surfactant, were fabricated by free-rising method. Temperature changes with time during foaming process were measured using a digital thermometer. RPUF foaming process was observed to undergo 2-step processes with temperature inflection around 60 sec after the start of reaction, and then reached slowly the max. temperature. While the max. temperature of neat PUF was measured as ca. $120^{\circ}C$, that of the samples with MWCNT were as higher value as ca. $130^{\circ}C$, and, even the time to reach that temperature was reduced by about 15 sec. Average cell size of PUF samples decreased from 185.1 for the neat PUF to $162.9{\mu}m$ for the sample of 0.01 phr of MWCNT. As the result, it was considered that MWCNT in RPUF foaming process could play a roll both as a nucleating agent and as a catalyst.

Rotor Time Constant Compensation of Induction Motor by Estimating Deviation Angle (회전자 자속 이탈각 추정을 이용한 유도전동기의 회전자 시상수 보상)

  • Cha, Young-Kil;Jung, Jong-Jin;Kim, Heung-Geun
    • Proceedings of the KIEE Conference
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    • 1995.11a
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    • pp.264-267
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    • 1995
  • In indirect vector control, if the value or the rotor tine constant used in slip calculation is different from the actual rotor time constant because of the temperature rising and flux saturation level, model flux angle and actual flux angle is different so that the transient and steady state response is degraded. In this paper, flux deviation angle is calculated by using actual torque and reference torque, and this flux deviation angle is summed to slip angle, therefore rotor flux angle is always accurate and indirect vector control is satisfied.

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A Study on th Real-time Measurement of Radio which Reach from Japan (일본에서 도래하는 전파의 실시간 측정에 관한 연구)

  • 배재영;배대환;김동일
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2000.10b
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    • pp.29-35
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    • 2000
  • As the increasing demand of the radio wave communication and teh progreessing of communication system, the radio interference of neighbor nations is rising in the improtant matter. This problem is a delicate matter which must be dealt diplomatically with by having a distinct technical basis. For our country, after the radio interference has been occurred in TRS service on the south seashore due to the base stations located at Fukuoka in Japan, the radio interference problem of neighbor nations has risen importantly. In this paper, therefore, we has measured the radio wave that reach from Fukuoka in Japan to Pusan in Korea and also collected dat by real-time.

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Experimental Study of DC Coronas in Point-to-Plane Short Gap (지간적 직류Corona의 실질적 검토)

  • 오철한;이성만
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.32 no.5
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    • pp.157-163
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    • 1983
  • Positive and negative coronas in point-to-plane short gap have been investigated with the variations of point radius and gap length. Mainly the onset potentials and current pulses under various conditions were measured with a 70 MHz C.R.O. and a precise-controllable D.C. power supply. In the case of negative corona, the Trichel pulse corona, glow corona and spark regions were distinguished apparently and the critical gap lengths between them were also found clearly. In the case of positive corona, there are streamer corona, spark regions and the critical gap length between them, too. The current pulse forms of Trichel pulse corona of negative and streamer pulse corona of positive are similar in rising time, peak-to-peak time and pulse width. The glow corona current shows D.C. component in form.

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Optimum Tuning of a Modified IMC-PID Controller Considering Model Uncertainty (모델 불확실성을 고려한 변형된 IMC-PID 제어기의 최적 동조)

  • Kim, Chang-Hyun;Lim, Dong-Kyun;Suh, Byung-Suhl
    • Proceedings of the KAIS Fall Conference
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    • 2006.05a
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    • pp.348-351
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    • 2006
  • This paper proposes a modified IMC-PID controller that introduces controlling factor of the system identification to the standard IMC-PID controller in order to meet the design specifications such as gain, phase margin and maximum magnitude of sensitivity function in the frequency domain as well as the design specifications in time domain, settling, rising time and overshoot, and so on.

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An Study on Basis for Demand Estimation of Lifetime Sports Facilities (생활체육시설의 수요예측을 위한 기초적 연구)

  • Min, Young-Gi
    • Journal of The Korean Digital Architecture Interior Association
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    • v.3 no.1
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    • pp.15-22
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    • 2003
  • The purpose of this study was to analyze basic conditions for the demand estimation erection of lifetime sports facilities. This is described the whole concept of lifetime sports(sport for all) for helping the understanding of its concept correctly. Firstly, second chapter was examined the significance, function and role of lifetime sports in modern society. Secondly, third and forth chapter was examined demand and participation of lifetime sports activities for demand estimation of lifetime sports facilities. Participation rate is on the rise by the increase in income and leisure time to some extent, but after that it stops rising. In other words, the same participation rate persists without additional increase in participation by the changes in time deepening and in the patterns of demand for lifetime sports activities.

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Design of PI Controller for DC ServoMotor Speed Control Using Genetic Algorithm (유전알고리즘을 이용한 직류 서보 모터 속도제어용 PI제어기의 설계)

  • Park, Han-Suk;Park, Hyun-Ju;Him, Dong-Wan;Hwang, Gi-Hyun;Woo, Jung-In
    • Proceedings of the KIEE Conference
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    • 2002.07d
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    • pp.2111-2113
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    • 2002
  • This paper proposes the design of PI controller using real-coding genetic algorithm showing a good performance on convergence velocity and diversity of population among evolutionary computations. To evaluate the proposed method's effectiveness, we apply the proposed GA-PI controller to the speed control of an actual DC servomotor system. The experimental results show that GA-PI controller has the better control performance than PI controller in terms of settling time rising time and overshoot.

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