• Title/Summary/Keyword: control period

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Physicochemical and Sensory Characteristics of Traditional Doenjang Prepared using a Meju Containing Components of Acanthopanax senticosus, Angelica gigas, and Corni fructus (가시오가피, 당귀와 산수유 성분이 함유된 메주로 제조한 전통 된장의 이화학적 특성 및 관능적 특성)

  • Lee, Yim-Jin;Han, Jin-Suk
    • Korean journal of food and cookery science
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    • v.25 no.1
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    • pp.90-97
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    • 2009
  • Changes in the quality characteristics of doenjang prepared with a meju containing components of Acanthopanax senticosus, Angelica gigas and Corni fructus during storage were evaluated. Three types of doenjang produced using each of these components showed lower Hunter's L and a values than the values of the control during the initial stage of storage: however, these values were similar to those of the control after 60 days of storage. Doenjang containing A. gigas showed a similar degree of browning to that of the control during the early stage of storage, while the degree of browning observed in the other samples was much higher than that og the control during this period. Despite these initial differences, the browning in all samples became similar after extended storage. The level of acidity increased gradually for up to 60 days, after which it decreased slightly. The pH of all treatments decreased with storage time. The amino-N contents of all types of doenjang increased gradually, reaching peak values after 60 days. Doenjang with A. senticosus and A. gigas had a strong characteristic flavor that reduced the native flavor of doenjang. Doenjang with C. fructus showed a similar overall palatability to that of the control.

Characteristics of Dynamic Postural Control in Anteroposterior Perturbation of a Platform (전후방향의 플랫폼 이동에 대한 동적균형 회복 특성)

  • 태기식;김영호
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.1066-1069
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    • 2002
  • Dynamic postural control varies with the environmental context, specific task and intentions of the subject. In this paper, dynamic postural control against forward-backward perturbations of a platform was estimated using tri-axial accelerometers and a force plate. Ten young healthy volunteers stood upright in comfortable condition on the perturbation system which was controlled by an AC servo motor. With anterior-posterior perturbations, movements of ankle, knee and hip Joints were obtained by tri-axial accelerometers. and ground reaction forces with corresponding displacements of the center of pressure(CoP) by the force plate. The result showed that the ankle moved first and the trunk forward, which implies that the mechanism of the dynamic postural control in forward-backward perturbations, occurred in the procedure of the ankle, the knee and the hip. Knee flexion and hip extension in the period of acceleration, constant velocity and deceleration phase is very important fur the balance recovery. These responses depends on the magnitude and timing of the perturbation. From the present study the accelerometry-system appears to be a promising tool for understanding kinematic accelerative In response to a transient platform perturbation. A more through understanding of balance recovery mechanism may aid in designing methods for reducing falls and the resulting injuries.

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A study on the Flux Feedback Approach for the Rejection of Dynamic Disturbance Forces in a Magnetically Suspended System (자기력 부상 시스템에서 외란 제거를 위한 자속 궤환 방식에 관한 연구)

  • Lee, Jun-Ho;Shin, Kyeong-Ho;Lee, Kang-Mi;Kim, Bak-Hyun;Kim, Jong-Ki;Kim, Yong-Kyu
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.05a
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    • pp.1212-1217
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    • 2006
  • This study is concerned with static and sinusoidal disturbance rejection for a single periodic input disturbance with known period. In the area of active elimination of a disturbance force, the control input should have two different kinds of gains: one is to deliver a stable control and the other is a force component to cancel the external disturbance force. In this paper we employ a simple state feedback control law to make the balance beam stable and employ a linear observer to estimate the states which represent the external disturbance force components. Simulation results verify our proposed control method to reject a static and sinusoidal disturbance force.

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Effect of Splenectomy on the Blood Component and Reproductive Performance accordingto Gestation in Rats (비장적출이 임신 rat의 혈액성분 및 번식력에 미치는 영향)

  • 정원철;오석두;성환후;정진관;윤창현;이병오
    • Korean Journal of Animal Reproduction
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    • v.18 no.3
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    • pp.167-174
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    • 1994
  • This experiment was undertaken to investigate the effect of splenectomy on the hematology and maintenance of pregnant rats. Those animals that had shown regular 4 or 5 day estrous cycles for more than two cycles were used. The day after mating ws designated Day 0 of pregnancy. Spleen was removed from Day 0(early), 6(middle) and 13(late) of pregnant rat, respectively. Blood was collected on Day 1, 7, 14 and 21 of the pregnancy. 1. The total serum protein was increased significantly (P<0.05) to the progress of pregnancy in control rat. All rats that splenectomized groups were decreased significantly(P<0.05) at Day 21 of pregnancy than control rats. 2. Albumin was not significantly changed. 3. Globulin was decreased significantly(P<0.05) between contol and middle treatment at Day 7, 14 of pregnancy. 4. Glucose was increased for the due to the pregress of pregnancy. It was no significance differences among the each groups. 5. Rate of abortion was increased in groups of early and middle of splenectomy compared with control. 6. Period of pregnancy was delayed in middle and late splenectomized gruops companed with control. 7. Litter size was lowed significantly (P<0.05) in early and middle splenectomized groups compared with control.

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Development and Performance Evaluation of Optimal Control logics for the Two-Position- and Variable-Heating Systems in Double Skin Facade Buildings (이중외피 건물 난방시스템의 발정제어 및 가변제어를 위한 최적로직의 개발 및 성능평가)

  • Baik, Yong Kyu;Moon, Jin Woo
    • KIEAE Journal
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    • v.14 no.3
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    • pp.71-77
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    • 2014
  • This study aimed at developing and evaluating performance of the two logics for respectively operating two-position- and variable-heating systems. Both logics control the heating system and openings of the double skin facade buildings in an integrated manner. Artificial neural network models were applied for the predictive and adaptive controls in order to optimally condition the indoor thermal environment. Numerical computer simulation methods using the MATLAB (Matrix Laboratory) and TRNSYS (Transient Systems Simulation) were employed for the performance tests of the logics in the test module. Analysis on the test results revealed that the variable control logic provided more comfortable and stable temperature conditions with the increased comfortable period and the decreased standard deviation from the center of the comfortable range. In addition, the amount of heat supply to the indoor space was significantly reduced by the variable control logic. Thus, it can be concluded that the optimal control method using the artificial neural network model can work more effectively when it is applied to the variable heating systems.

The study on the distribute type liner encoder (분배용 선형 엔코더의 개발)

  • Park, Hyun-Ju;Park, Sung-Jun;Kim, Jong-Dal;Shon, Mu-Heon;Kim, Gyu-Seob;Lee, Yil-Chun
    • Proceedings of the KIEE Conference
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    • 2001.07e
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    • pp.127-133
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    • 2001
  • In SRM drive, the ON OFF angles of each phase switch should be accurately controlled in order to control the torque and speed stably. The accuracy of the switching angles is dependent upon the resolution of the encoder and the sampling period of the microprocessor, that are used to provide the information of the rotor position and to control the SRM power circuit, respectively. However, as the speed increases, the amount of the switching angle deviation from the preset values is also increased. Therefore, the low cost encoder suitable for the practical and stable SRM drive is proposed and the control algorithm to provide the switching signals using the simple digital logic circuit is also presented in this paper. As a result, a stable high speed SRM drive can be achieved by the high resolution switching angle control and it is verified from the experiments that the proposed encoder and logic controller can be a powerful candidate for the practical low cost SRM drive.

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The Effect of a Social Skills Program on Violent Behaviors in Children Aged 60~72 Months

  • Kuzlu Ayyildiz, Tulay;Cimete, Guler
    • Journal of Korean Academy of Nursing
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    • v.49 no.6
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    • pp.771-782
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    • 2019
  • Purpose: To determine the effects of a child and parent program on developing social skills for preventing violent behaviors in children aged 60~72 months through a specially developed pre and posttest, control group, quasi-experimental study. Methods: A social skills development program based on Gardner's Multiple Intelligence Theory was used. The data were collected using the Social Skills Assessment Scale (SSAS), a Chart to Monitor Verbal and Behavioral Violence in Children, the Parental Attitude Scale and the Parent Interview Form. This quasi-experimental study that included a pretest, posttest, and control group had a sample comprising 67 children and parents, with 36 in the experimental group, and 31 in the control group. Results: Over a six-month period, while the social skill scores of the children in the experimental and control groups increased, their violent behaviors decreased (p<.050). Increase in social skill scores and decrease in violent behaviors were higher in the experimental than in the control group children (p<.050). The parents in the experimental group stated that they had started to empathize with their children, using "I" language, and applied rules more consistently after the program. Conclusion: This program was successful in preventing violent behaviors in children through the development of social skills. Hence, it can be effectively implemented through a teacher/nurse collaboration.

Optimum MPPT Control Period for PV Panel based on Real Insolation Profile (실제 일사프로파일에 근거한 PV 패널의 최적 MPPT 제어주기)

  • Ryu, Danbi;Kim, Yong-Jung;Jeong, Woo-Yong;Kim, Hyosung
    • Proceedings of the KIPE Conference
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    • 2018.07a
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    • pp.123-125
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    • 2018
  • 태양광발전시스템은 낮은 효율의 PV 패널을 사용하여 최대의 전력을 생산하기 위해 PV 패널의 최대전력점에서 운전하는 MPPT(Maximum Power Point Tracking) 제어가 반드시 필요하다. 기존의 MPPT 알고리즘은 대부분 경사법에 기초하고 있으며 그 중 대표적인 방법이 P&O(Perturb and Observe) 알고리즘이다. P&O 알고리즘의 MPPT 성능을 좌우하는 두 가지 인수는 MPPT 제어주기와 변량전압의 크기이다. MPPT 제어기의 빠른 동특성과 극대화된 효율을 위한 최적의 MPPT 제어주기와 변량전압의 크기를 결정하기 위해서는 실제 날씨 환경에서 다양한 일사량 프로파일 패턴에 대한 MPPT 제어기의 성능분석이 필수적이다. 본 논문에서는 대한민국 중부지역의 전형적인 맑은 날씨와 흐린 날씨에서 실제 일사량을 측정하고, 취득한 일사량데이터를 기초로 저자가 개발한 다이오드 등가모델을 적용하여 시뮬레이션을 수행하였다. 이를 기반으로 MPPT 제어주기의 설정값에 따른 PV 패널의 전력생산량을 예측하여 MPPT 목표 효율을 극대화할 수 있는 최적의 MPPT 제어주기를 제시한다.

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Simplified Model Predictive Control Method for Three-Phase Four-Leg Voltage Source Inverters

  • Kim, Soo-eon;Park, So-Young;Kwak, Sangshin
    • Journal of Power Electronics
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    • v.16 no.6
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    • pp.2231-2242
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    • 2016
  • A simplified model predictive control method is presented in this paper. This method is based on a future reference voltage vector for a three-phase four-leg voltage source inverter (VSI). Compared with the three-leg VSIs, the four-leg VSI increases the possible switching states from 8 to 16 owing to a fourth leg. Among the possible states, this should be considered in the model predictive control method for selecting an optimal state. The increased number of candidate switching states and the corresponding voltage vectors increase the calculation burden. The proposed technique can preselect 5 among the 16 possible voltage vectors produced by the three-phase four-leg voltage source inverters, based on the position of the future reference voltage vector. The discrete-time model of the future reference voltage vector is built to predict the future movement of the load currents, and its position is used to choose five preselected vectors at every sampling period. As a result, the proposed method can reduce calculation load by decreasing the candidate voltage vectors used in the cost function for the four-leg VSIs, while exhibiting the same performance as the conventional method. The effectiveness of the proposed method is demonstrated with simulation and experiment results.

A Study on PID Control Law's Realization for 2-Stage Proportional Pressure Control Valve with Analog Controller (아날로그 PID 제어기를 이용한 2단 비례 압력 제어 밸브의 실현에 관한 연구)

  • Yun, S.N.;Jeong, H.H.
    • Journal of Drive and Control
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    • v.9 no.4
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    • pp.58-61
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    • 2012
  • The customers who used the hydroulic system desire the product that has more detailed specification quickly during the industrial technology is developed. Every researcher try to reduce the developed period and to satisfy the customers' desire. Lot's of simulation software and hardware already was used to be satisfied those purpose. But these kind of equipment need a lot of cost to set up and technical knowledge to drive that system. This paper concerns about analog PID controller that can be assembled with a few resistor, condenser and optional amplifier and doesn't need technical knowledge to drive. At the first, the plant was modeled mathematically to design the analog PID controller's circuit. After that, PID controller's parameter was selected by customers' desire. Finally, the analog PID controller's circuit was assembled from the control law. The circuit's availability was confirmed by step response test in the controlled system.