• Title/Summary/Keyword: control period

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Bias Compensation Algorithm of Acceleration Sensor on Galloping Measurement System

  • Kim, Hwan-Seong;Byung, Gi-Sig;So, Sang-Gyun
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.127.6-127
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    • 2001
  • In this paper, we deal with two bias compensation algorithms of acceleration sensor for measuring the galloping on power transmission line. Firstly, the block diagram of galloping measurement system is given and a galloping model is presented. Secondly, two compensation algorithms, a simple compensation and a period compensation, are proposed. A simple compensation algorithm use the drafts of velocity and distance at fixed periods, so it is useful for constant bias case. Next, a period compensation algorithm can compensate a periodic bias. This algorithm use the previous measured data and compensated data for constant period, where the period is obtained by FFT method. Lastly, the effectiveness of proposed algorithms is verified by comparing between two algorithms in simulation, and its characteristics and the bias error bound are shown, respectively.

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Auto Alarm System of Replacement Period for Vehicle Cabin Filter & Interception System of High Concentration Dust (차량용 에어컨필터 교환시점 알림 시스템 및 과농도 먼지 차단 시스템)

  • Lee, Kyu-Se;Byeon, Seong-Uk;Kim, Yeong-Min;Park, Sung-Woo;Yum, Young-Jin
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.32 no.11
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    • pp.1035-1040
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    • 2008
  • Replacement period for vehicle cabin filter of most automobiles is fixed without consideration of conditions of filter and environment. Auto alarm system of replacement period at vehicle cabin filter and interception system of high concentration dust were developed. Control program which is related with the AQS has been developed based on the circuit drive algorithm. This system is expected to be beneficial to passenger's health and to extend the life of the filter which regulates vehicle HVAC system by ventilation mode change at the time of high concentration dust.

Influence of Different Soil Moisture on the Growth of Lespedeza bicolor (싸리나무에 있어서 수분공급량이 생장에 미치는 영향)

  • 이호준
    • Journal of Plant Biology
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    • v.18 no.4
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    • pp.143-149
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    • 1975
  • For the evaluation of drought resistance of the plant, the growth of Lespedeza bicolor Turcz. var. japonica Nakai was analyzed by the control of water content of soil: 1. The growth of leaf, stem and root showed high value in accordance with the increase of soil water content. 2. The formation of nodule was alos increased as the content of soil water became higher. 3. The highest water content of the plant was shown in the plots of 30 and 40% of water centent in soils and in the middle of the growing period (August-September). 4. The C/F ratio in the early period of the growth(July) was similar in each plot, but showed a higher value as the water centent of soil became higher at the later period(October). 5. The T/R ration increased in early period of the growth as the soil water content became higher, but it was decreased to the value of 1 in each plot.

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Acupuncture for Prehypertension and Stage 1 Hypertension in Postmenopausal Women: A Randomized Controlled Pilot Trial (폐경 후 고혈압 전단계 및 1기 고혈압에 대한 침 치료 효과: 무작위 대조 예비연구)

  • Kim, Jung-Eun;Choi, Sun-Mi;Choi, Jin-Bong;Kim, Hyeong-Jun;Kwon, Ojin;Kim, Jae-Hong;Park, Ji-Eun
    • Korean Journal of Acupuncture
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    • v.34 no.3
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    • pp.116-125
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    • 2017
  • Objectives : The aim of this study was to assess the effectiveness of acupuncture in treating prehypertension and stage 1 hypertension in postmenopausal women. Methods : The study was a multi-center, four-arm, non-blinded, randomized clinical trial. Sixty participants were randomly assigned to experimental or control groups. The experimental groups received 10 acupuncture sessions over 4 weeks(Group A, n=20) or 20 sessions over 8 weeks(Group B, n=20) along with usual care. The acupoints were GB20, LI11, ST36, and SP6, bilaterally. The acupuncture groups were followed-up for an additional 12 weeks after acupuncture treatment. The control groups received usual care for 16 weeks(Group C, n=10) or 20 weeks(Group D, n=10). The outcomes were blood pressure, blood pressure control rates, lipid profile, and high-sensitivity C-reactive protein(hs-CRP). Results : After 4 weeks, DBP in the acupuncture groups(A+B) showed no significant decrease compared to the control group(C+D). However, after 8 weeks of acupuncture treatment, group B showed a significant decrease in DBP after acupuncture treatment and follow-up period compared to control group. Although there was no difference between the acupuncture and control groups in SBP after acupuncture treatment, group B showed a significant decrease in SBP compared to control group after follow-up period. Lipid profiles and hs-CRP did not differ significantly between acupuncture and control groups. Conclusions : Acupuncture treatment for 8 weeks showed the effect on prehypertension and mild hypertension. To verify the effect of acupuncture on blood pressure, rigorous trials including more participants are required.

Control of dissolved Oxygen Concentration and Specific Growth Rate in Fed-batch Fermentation (유가식 생물반응기에서의 용존산소농도 및 비성장속도의 제어)

  • Kim, Chang-Gyeom;Lee, Tae-Ho;Lee, Seung-Cheol;Chang, Yong-Keun;Chang, Ho-Nam
    • Microbiology and Biotechnology Letters
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    • v.21 no.4
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    • pp.354-365
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    • 1993
  • A novel control method with automatic tuning of PID controller parameters has been developed for efficient regulation of dissolved oxygen concentration in fed-batch fermentations of Escherichia coli. Agitation speed and oxygen partial pressure in the inlet gas stream were chosen to be the manipulated variables. A heuristic reasoning allowed improved tuning decisions from the supervision of control performance indices and it coule obviate the needs for process assumptions or disturbance patterns. The control input consisted of feedback and feedforword parts. The feedback part was determined by PID control and the feedforward part is determined from the feed rate. The proportional gain was updated on-line by a set of heuristics rules based on the supervision of three performance indices. These indices were output error covariance, the average value of output error, and input covariance, which were calculated on-line using a moving window. The integral and derivative time constants were determined from the period of output response. The specific growth rate was maintained at a low level to avoid acetic acid accumulation and thus to achieve a high cell density. The specific growthe rate was estimated from the carbon dioxide evolution rate. In fed-batch fermentation, the simutaneous control of dissolved oxygen concentration (at 0.2; fraction of saturated value) and specific growth rate (at 0.25$hr^{-1}$) was satisfactory for the entire culture period in spite of the changes in the feed rate and the switching of control input.

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Effect of Anti-juvenile Hormone Analogue (AJH) on the Larval Ecdysis of the Silkworm, Bombyx mori L. (항유약호르몬 활성물질이 누에탈피에 미치는 영향)

  • 홍성진;이화준
    • Journal of Sericultural and Entomological Science
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    • v.39 no.2
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    • pp.161-168
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    • 1997
  • To clarify the effect of anti-juvenile hormone analogue (AJH) on the larval ecdysis by feeding at early stage of the 4th instar, the total amount of protein and activity of chitinolytic enzymes in the integument of Bombyx mori were analyzed, PAGE pattern of the protein was observed and the morphological changes of integument during molting period were also observed and the morphological changes of integument during molting period were also observed by means of TEM. The total amount of protein was greatly increased in premolting, then reached maximum level just before ecdysis, and rapidly decreased after the larval ecdysis in the control, while in the AJH treatment, increased 12 hr later than the control and its maximum was only 82.6% of the control. Two specific proteins, which were presumed as the protein originated from endocuticle, also appeared 12 hr later than the control and were maintained to 132 hr after AJH treatment from the aspects of the Native- and SDS-PAGE patterns, although those of the control disappeared instantly after ecdysis. Chitinase and $\beta$-N-acetylglucosaminidase activities were also suppressed and delayed by AJH treatment. Furthermore, it was observed that the apolysis took place 12 hr later than the control but new epicuticle was not formed at least until 132 hr after AJH treatment. From these results, it is suggested that the larval molting process of silkworm develops 12 hr later than the control but new epicuticle was not formed at least until 132 hr after AJH treatment. From these results, it is suggested that the larval molting process of silkworm develops 12 hr later than the control by AJH treatment but no further processing takes place just after apolysis.

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Adaptive Repetitive Control for an Eccentricity Compensation of Optical Disk Drive (광 디스크 드라이브의 편심 보상을 위한 적응 반복 제어)

  • Seo, Sam-Jun;Kim, Dong-Won;Park Gwi-Tae
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.2
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    • pp.135-142
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    • 2005
  • This paper presents an adaptive repetitive control scheme for optical disk drives to track a variable periodic reference signal. Periodic disturbances can be adequately attenuated using the concept of repetitive control, provided the period is known. Because optical disk drives support various speeds, they have the varying periodic disturbances. Based on repetitive control to change sampling frequency to follow the change of reference period, an adaptive repetitive control is proposed in order to deal with such disturbances. The proposed control consists of the repetitive controller and the frequency generator. The former uses a varying sampler operating at fixed multiple times of the disturbance frequency and the latter generates the changeable sampling frequency based on the disturbance frequency. The experimental results on the control of an optical disk drive demonstrate the effectiveness of the proposed schemes and the improvement of random access time as well.

Comparing Bio-efficacy of Liquid DL-methionine Hydroxy Analogue Free Acid with DL-methionine in Broiler Chickens

  • Mandal, A.B.;Elangovan, A.V.;Johri, T.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.1
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    • pp.102-108
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    • 2004
  • The present experiment was conducted to assess the efficacy of methionine hydroxy analogue free fatty acid (MHAFA) in comparison to DL-methionine (DL-Met) utilizing day-old commercial broiler chicks (n=300). The chicks were randomly distributed into 30 groups of 10 chicks each. Three dietary treatments, viz. D1-maize-soybean meal based basal diet (Control), D2- control diet supplemented with DL- methionine to meet its requirements and D3-control supplemented with MHA-FA @ 1.54 times of DL-methionine used in D2, were formulated. Each dietary treatment was offered to 10 replicated groups of chicks following completely random design (CRD). The chicks fed on supplemental DL-Met had significantly higher (p<0.01) gain in body weight, followed by MHA-FA group and control during 0-3 weeks of age. During overall growth period (0-6 weeks), chicks in DL-Met and MHA-FA groups grew better (p<0.01) than those in control. Feed conversion ratio (FCR) improved (p<0.01) on supplementation of either DL- Met or MHA-FA in the basal (Control) diet during 0-3 weeks of age. The FCR for overall period, however, did not differ statistically (p>0.05) amongst the treatments. The eviscerated yields emanated from diets with DL-Met or MHA-FA were higher (p<0.01) than that in Control. Abdominal fat pad was also more (p<0.01) in broilers fed control diet than in DL-Met or MHA-FA supplemented group. Breast yield was higher (p<0.05) in MHA-FA fed broilers than those fed DL-methionine supplemented or un-supplemented diets. The efficacy of MHA-FA in comparison to DL-Met for growth was 62.11, 64.82 and 63.88% and for feed efficiency was 62.98, 67.73 and 64.01% at 0-3, 3-6 and 0-6 weeks of age, respectively, while it was 65.85, 71.40 and 67.49% for eviscerated yield, abdominal fat pad reduction and breast yield at 6 weeks of age, respectively.

Effects of Agricultural Reservoir Rehabilitation on their Flood Control Capacities (농업용 저수지 둑 높이기에 따른 홍수조절효과 분석)

  • Jun, Sang Min;Kang, Moon Seong;Song, Inhong;Hwang, Soon Ho;Kim, Kyeung;Park, Jihoon
    • Journal of The Korean Society of Agricultural Engineers
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    • v.55 no.6
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    • pp.57-68
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    • 2013
  • About 74 % of reservoirs in Korea are older than 40 years and their storage capacities have been decreased substantially. As part of reservoir reinforcement, the dam heightening project has been ongoing for about 110 reservoirs. The main purpose of the dam heightening project is to secure additional environmental water, while improving flood control capacity by gaining additional storage volume. The objective of this study was to evaluate reservoir flood control capacity changes of dam heightening reservoirs for effective management of additional storage volume. In this study, 13 reservoirs were selected for reservoir simulation of 200 year return period floods. Rainfall data of 1981-2100 were collected and divided into 4 periods (1981-2010; 1995s, 2011-2040; 2025s, 2041-2070; 2055s, 2071-2100; 2085s). Probability rainfalls and 200yr design floods of each period were calculated using FARD2006 and HEC-HMS. Design floods were used as inputs of each reservoir simulation using HEC-5. Overall, future probability rainfalls and design floods tend to increase above the past 1995s. Control ratios were calculated to evaluate flood control capacities of reservoirs. As a result, average flood control ratios were increased from 32.6 % to 44.2 % after dam heightening. Control ratios were increased by 12.7 % (1995s), 12.4 % (2025s), 10.3 % (2055s) and 10.9 % (2085s). The result of this study can be used as a basis for establishing the reservoir management structure in the future.

Identification of Subgroups with Poor Glycemic Control among Patients with Type 2 Diabetes Mellitus: Based on the Korean National Health and Nutrition Examination Survey from KNHANES VII (2016 to 2018) (제 2형 성인 당뇨병 유병자의 혈당조절 취약군 예측: 제7기(2016-2018년도) 국민건강영양조사 자료 활용)

  • Kim, Hee Sun;Jeong, Seok Hee
    • Journal of Korean Biological Nursing Science
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    • v.23 no.1
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    • pp.31-42
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    • 2021
  • Purpose: This study was performed to assess the level of blood glucose and to identify poor glycemic control groups among patients with type 2 diabetes mellitus (DM). Methods: Data of 1,022 Korean type 2 DM patients aged 30-64 years were extracted from the Korea National Health and Nutrition Examination Survey VII. Complex samples analysis and a decision-tree analysis were performed using the SPSS WIN 26.0 program. Results: The mean level of hemoglobin A1c (HbA1c) was 7.22±0.25%, and 69.0% of the participants showed abnormal glycemic control (HbA1c≥6.5%). The characteristics of participants associated with poor glycemic control groups were presented with six different pathways by the decision-tree analysis. Poor glycemic control groups were classified according to the patients' characteristics such as period after DM diagnosis, awareness of DM, sleep duration, gender, alcohol drinking, occupation, income status, low density lipoprotein-cholesterol, abdominal obesity, and number of walking days per week. Period of DM diagnosis with a cut-off point of 6 years was the most significant predictor of the poor glycemic control group. Conclusion: The findings showed the predictable characteristics of the poor glycemic control groups, and they can be used to screen the poor glycemic control groups among adults with type 2 DM.