• Title/Summary/Keyword: control period

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Physicochemical Properties of Ground Pork with Safflower (Carthamus tinctorius L.) Seed during Refrigerated Storage (홍화씨가 분쇄돈육의 냉장 중 이화학적 품질에 미치는 영향)

  • Park, Kyung-Sook;Kim, Min-Ju;Park, Hyun-Suk;Choi, Young-Joon;Jung, In-Chul
    • Korean journal of food and cookery science
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    • v.28 no.4
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    • pp.399-405
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    • 2012
  • This study was carried out to investigate the effect of safflower seed powder on the physicochemical characteristics of ground pork during refrigerated storage. Three types of ground pork were evaluated: 20% pork fat added (PF, control), 10% pork fat and 10% added safflower seed powder (PFS), and 20% added safflower seed powder (SS). The pH increased during storage, but decreased after 10 days of the storage (p<0.05). The pH was lower in PFS and SS than that in PF after 10 days of storage (p<0.05). The TBARS (2-thiobarbituric acid reactive substances) values increased with longer storage period (p<0.05), and those of PF, PFS and SS were 1.186, 0.686 and 0.577 mg MA/kg, respectively, after 10 days of storage. The $L^*$ values for external color of PF and PFS decreased (p<0.05), but that of SS was not significantly different after a longer storage period. The $a^*$ values decreased (p<0.05), but the $b^*$ values were not significantly different with longer storage period. The $L^*$ values for internal color of PFS and SS decreased (p<0.05), but that of PF was not significantly different with longer storage period. The $a^*$ value of PF decreased (p<0.05), but that of SS increased with longer storage period. The $b^*$ value decreased (p<0.05), but those of PFS and SS were not significantly different with longer storage period. Water holding capacity decreased with longer storage period, and that of SS was the highest (p<0.05). Cooking loss of PFS and SS was not significantly different with longer storage period, and that of PF was the highest (p<0.05). The reduction in diameter of the samples was not significantly different with longer storage period, and that of PF was the highest (p<0.05). Hardness and chewiness of samples increased, but springiness and cohesiveness decreased with longer storage period (p<0.05). Replacing animal fat with safflower seed powder was effective and may be useful as an innovative meat product.

An Adaptive Moving Average (A-MA) Control Chart with Variable Sampling Intervals (VSI) (가변 샘플링 간격(VSI)을 갖는 적응형 이동평균 (A-MA) 관리도)

  • Lim, Tae-Jin
    • Journal of Korean Institute of Industrial Engineers
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    • v.33 no.4
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    • pp.457-468
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    • 2007
  • This paper proposes an adaptive moving average (A-MA) control chart with variable sampling intervals (VSI) for detecting shifts in the process mean. The basic idea of the VSI A-MA chart is to adjust sampling intervals as well as to accumulate previous samples selectively in order to increase the sensitivity. The VSI A-MA chart employs a threshold limit to determine whether or not to increase sampling rate as well as to accumulate previous samples. If a standardized control statistic falls outside the threshold limit, the next sample is taken with higher sampling rate and is accumulated to calculate the next control statistic. If the control statistic falls within the threshold limit, the next sample is taken with lower sampling rate and only the sample is used to get the control statistic. The VSI A-MA chart produces an 'out-of-control' signal either when any control statistic falls outside the control limit or when L-consecutive control statistics fall outside the threshold limit. The control length L is introduced to prevent small mean shifts from being undetected for a long period. A Markov chain model is employed to investigate the VSI A-MA sampling process. Formulae related to the steady state average time-to signal (ATS) for an in-control state and out-of-control state are derived in closed forms. A statistical design procedure for the VSI A-MA chart is proposed. Comparative studies show that the proposed VSI A-MA chart is uniformly superior to the adaptive Cumulative sum (CUSUM) chart and to the Exponentially Weighted Moving Average (EWMA) chart, and is comparable to the variable sampling size (VSS) VSI EWMA chart with respect to the ATS performance.

Direct Torque Control Of Induction Motor for Constant Switching Frequency (일정 스위칭 주파수를 위한 유도전동기의 직접토오크 제어)

  • Choi, Youn-Ok;Chung, Byung-Ho;Lim, Byung-Ok;Jeong, Sam-Young;Seo, Jin-Yeon;Cho, Geum-Bae;Baek, Hyung-Lae
    • Proceedings of the KIEE Conference
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    • 2002.07b
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    • pp.1152-1154
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    • 2002
  • In this paper, a direct torque control method of an induction motor is proposed which enables constant switching frequency. The switching strategy of a conventional direct torque control scheme which is based on hysteresis comparator results in a variable switching frequency which depends on the speed, flux, stator voltage and hysteresis band of the comparator. This paper proposes a new switching strategy which determine the effective switching time on each switching period by comparing the ascending and descending torque slopes. The simulation results are presented to verify this proposed scheme.

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Low Speed Drive of Induction Motor using Direct Toque Control (DTC를 이용한 유도전동기의 저속 영역운전)

  • Song, Ho-Bin;Lee, Chun-Sang;Seo, Young-Soo
    • Proceedings of the KIEE Conference
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    • 2002.07b
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    • pp.1178-1180
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    • 2002
  • A control technique which utilizes the stator flux components as control variables has been applied to a speed sensorless induction motor drive. The scheme may be regarded as a development of a DTC scheme, aimed achieve constant switching frequency operation. At each sampling period the required voltage vector is calculated on the basis of the error between the reference and the estimated stator flux vector. The problems related to the VSI dead time and the stator flux estimation at low speed have been analyzed, and an efficient solution has been proposed.

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A Development of Acoustic Release System in the Seafloor (심해저용 원격 착탈 제어 시스템의 개발)

  • Kim, Young-Jin;Huh, Kyung-Moo;Jeong, Han-Cheol
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.9
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    • pp.774-780
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    • 2005
  • For the accurate inspection of the resources and space in the ocean, the method of locating the measurement equipments in the seafloor and retrieving these equipments later after a certain period of time. is generally used. In this method, the reliability of retrieving measurement equipments is very important. In our proposed remotely-controlled acoustic release system, an underwater ultrasonic wave recognition algorithm by which we can recognize the sound signal without the influence of disturbances due to underwater environment changes is developed, and a battery is used for the reduction of electric power consumption. we show the effectiveness of our proposed system through experimental results.

Design and control of the precision heat actuator using thermoelectric device (열전소자를 이용한 정밀 열구동기구의 설계 및 제어)

  • 서장렬;김선민;이선규
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.395-398
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    • 1997
  • In the modem manufacturing system, to achieve the unmanned automation, the stability of accuracy is required through a long working period. The thermal deformation of precision machine is predominant in this long time stability. While grinding slender and long workpiece at cylindrical grinding machine, we support workpiece using steadies to prevent the vibration of workpiece. The thermal deformation of the machine by grinding and internal heat source cause processing errors, so the steadies for compensating the thermal deformation in real time are strongly needed. In order to compensate these thermal deformation and grinding processing errors, the device to determine the precise positioning having the stroke of 10.mu.m is necessary. This paper suggests design and make the device to determine the precise positioning using thermoelectric device, to investigate the control characteristics and presents the heat actuator will be very useful in machine tool.

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Control Method of Wind Induced Vibration Level for High-rise buildings (초고층 건물의 풍가속도응답 조절 기법)

  • Kim Ji-Eun;Seo Ji-Hyun;Park Hyo-Seon
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2005.04a
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    • pp.375-382
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    • 2005
  • In this paper, a practical control method of wind-induced vibration of high-rise buildings is presented in the form of resizing algorithm. In the structural design process for high-rise buildings, the lateral load resisting system for the building is more often determined by serviceability design criteria including wind-induced vibration level. Even though many drift method have been developed in various forms, no practical design method for wind induced vibration has been developed so far. Structural engineers rely upon heuristic or experience in designing wind induced vibration. The performance of the proposed method is evaluated by comparing wind-induced vibration levels estimated both from approximate techniques and wind tunnel test.

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Effects on Hyperalgesia of Electroacupuncture (전침자극이 통각과민에 미치는 효과)

  • Choi, Sug-Ju;Seo, Sam-Ki;Yoon, Se-Won;Lim, Sang-Wan;Choi, Eun-Young
    • Journal of the Korean Academy of Clinical Electrophysiology
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    • v.5 no.1
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    • pp.73-83
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    • 2007
  • This study aims to examine the effects on nociceptive neuron excitability by application of electroacupuncture in rat with inflammation. It used 20 rats for experiment, divided them into control group, electroacupuncture group (EA group), caused hyperalgesia by injecting ${\lambda}$-carrageenan into hindpaw and conducted treatment three times for experimental period. Change of NFR(reaction time, RMS) showed no significant differences among EA group showed significant differences compared to control group from 48 hours. This study showed that EA group had an effect on nociceptive neurone excitability. Therefore, it is considered that electroacupuncture for pain control will be very desirable.

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A Study on the Effects of Salinity and Washing in on Aerobic Composting of Food Wastes

  • Park, Seok-Hwan
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2004.06a
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    • pp.207-209
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    • 2004
  • This study was performed to estimate the effects of salinity and washing of food wastes on temperature, pH, and salinity in aerobic composting of food wastes. Weight ratios of food wastes to water in washing were 1:0(Control), 1:1(W-1), 1:2(W-2), 1:3(W-3) and 1:4(W-4), respectively. Ratios of food wastes to wood chips in reactor of Control, W-1, W-2, W-3 and W-4 were 5kg:5L, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The increase in the ratio of food wastes to water used in washing resulted in the decrease of the highest reaction temperature and the elongation of the high temperature reaction period. The lowering of the ratio of food wastes to water used in washing resulted in faster pH increase The final salinities of Control, W-1, W-2, W-3 and W-4 were 0.95%, 0.73%, 0.65%, 0.57% and 0.41%, respectively.

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Speed Control Characteristics of BLDCM by CR-PWM VSI of Constant Switching Frequency (일정 스위칭 주파수의 CR-PWM VSI에 의한 BLDCM의 속도제어 특성)

  • Kim, Jang-Mok;Kim, Kwang-Heon;Won, Jong-Soo
    • Proceedings of the KIEE Conference
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    • 1990.11a
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    • pp.53-57
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    • 1990
  • This paper propose Constant Frequency CR-PWM VSI. In which ON/OFF output of Hystersis comparator, which compares the amplitude of reference current with that of actual current, control the switching elements with a constant sampling period of $\mu$-processor. Speed control system of BLDCM driven by controller wi th CF CR - PWM VSI was built.

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