• Title/Summary/Keyword: low-order control

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Effect of Choice Feeding on the Nutrient Intake and Performance of Broiler Ducks

  • Men, Bui Xuan;Ogle, Brian;Lindberg, Jan Erik
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.12
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    • pp.1728-1733
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    • 2001
  • An experiment was conducted at the experimental duck farm of Cantho University in the Mekong Delta of Vietnam to evaluate the effects of offering pairwise feeds with different crude protein (CP) levels to Cherry Valley broiler ducks from 28-63 days of age on feed intake and performance. Five diets consisting of mixtures of soya bean meal, fish meal, maize meal and fine rice bran, were formulated to give isocaloric diets with 30, 24, 18, 16 and 12% CP. These were offered separately as pellets to growing ducklings in the following combinations: 30+18, 30+12, 24+16 and 18+12. A diet with 20% CP (CP20) was used as control. All the diets were offered ad libitum. Daily feed intakes (g dry matter, DM) were 161, 168, 150, 101 and 143 g for the 30+18, 30+12, 24+16, 18+12 and CP20 treatments, respectively. CP intakes were 29.6, 27.0, 24.8, 17.1 and 22.9% of total DM intake, and the ratio of methionine+cystine to lysine was 0.76, 0.75, 0.75, 0.76 and 0.75 for the 30+18, 30+12, 24+16, 18+12 and CP20 treatments, respectively. Live weights at 63 days of age were 2,937, 3,054, 2,898, 2,200, and 2,811 g (p<0.001), and daily live weight gains 57.8, 61.7, 57.0, 38.5 and 55.7 g (p<0.001) for the 30+18, 30+12, 24+16, 18+12 and CP20 treatments, respectively. The weights and yields of the carcass, breast and thigh muscles, and heart decreased in the order 30+18, 30+12, 24+16, CP20 and 18+12 (p<0.001). The present study suggests that growing broiler offered a combination of high and low protein feeds pairwise will eat excessive amounts of the high protein feed, thus resulting in protein intakes above requirements.

The Experimental Study of the Interaction Between the Flow rind Temperature Field and a Boundary Layer Due to a Variety of tole Height of a Vortex Generator (와동 발생기 높이 변화에 대한 경계층 내의 유동장과 온도장에 관한 실험적 연구)

  • Gwon, Su-In;Yang, Jang-Sik;Lee, Gi-Baek
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.1
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    • pp.82-93
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    • 2002
  • The effects of the interaction between the flow and temperature field and a boundary layer due to a variety of the height of a vortex generator are experimentally investigated. The test facility consists of a boundary-layer wind tunnel with the vortex generator protruding from the bottom surface. In order to control the strength of the longitudinal vortices, the angle of attack and the spacing distance of the vortex generator are 20 degree and 40 mm, respectively. The height of the vortex generator (H) is 15 mm, 20 mm and 30 mm and the cord length of it is 50 mm. Three-component mean velocity measurements are made using a 5-hole probe system and the surface temperature distribution is measured by the hue capturing method using thermochromatic liquid crystals. By using the method mentioned above, the following conclusions are obtained from the present experiment. The boundary layer is thinned in the downwash region where the strong downflow and the lateral outflow of the boundary layer fluid occur and thickened in the upwash re,3ion where the longitudinal vortex sweeps low momentum fluid away from the bottom surface. In case that the height of the vortex generator increases, the averaged circulation and the maximum vorticity of the vortex pair decrease. The contours of the non-dimensional temperature show the similar trends fur all the cases (H=15 mm, 20 mm and 30 mm). The peak augmentation of the distribution of the local non-dimensional temperature occurs in the downwash region near the point of minimum boundary-layer thickness.

The Action and Pacemaker Potential in the Frog Truncus Arteriosus (개구리 대동맥의 활동전압 및 Pacemaker 전압에 관한 연구)

  • Earm, Yung-E;Sung, Ho-Kyung
    • The Korean Journal of Physiology
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    • v.16 no.2
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    • pp.119-128
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    • 1982
  • The frog truncus arterious were studied with conventional glass microelectrode technique in order to elucidate the underlying mechanism of spontaneous pacemaker activity. The analyses were focussed on the ionic nature of pacemaker current by changing the concentrations of extracellular $K^+$ and, $Na^+$, or by using blockers of K- and Ca-current and chronotropic transmitters. 1) The action potential of the spontaneously active truncus arteriosus has some characteristic feature of maximal distolic potential ranged from -65 to -75 mV, resting potential from -45 to -50 mV and overshoot voltage about +30 mV, respectively. Duration of the action potential taken from rapid upstroke to maximal diastolic potential was about 600 msec. Usual discharge rate was $25{\sim}30/min$ at room temperature $(18{\sim}20^{\circ}C)$. 2) The sensitivity of the resting membrane potential to change extracellular potassium concentrations $(0{\sim}12\;mM)$ was relatively low. Transient hyperpolarization was appeared in the 12 mM K Ringer after 10 min exposure to 0 mM K and it could be related to Na-pump reactivation by high potassium. 3) Reduction of extracellular sodium concetrations diminished the amplitude and frequency of the action potential. In Ringer solution containing 30% Na (substituted by equimolar Tris), spontaneous activity stopped but reappeared as very slow and small action potential. There was no spotaneous activity in zero Na Ringer solution. 4) Caesium(10 mM), K-current blocker decreased the frequency of the action potential and also pacemaker depolarization. Manganese (2 mM) known to be Ca-current antagonist, blocked spontaneous activity completely. 5) Adrenaline and acetylcholine had no chronotropic effect. But adrenaline increased the duration of plateau phase and the magnitude of the action potential in the follower cell. It is concluded that K-, Na-and Ca-current components are involved in the genesis of spontaneous activity of the frog truncus arteriosus like cardiac pacemaker tissues. But the insensitivity of truncus arteriosus to adrenaline and acetylcholine indicates that there are some different control mechanisms of spontaneous rhythm in two tissues.

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Reservoir Management in Flood Period with Chance Constrained LP (위험도제약(危險度制約) 선형계획법(線形計劃法)에 위한 홍수기(洪水期) 저수지운영(貯水池運營))

  • Lee, Kil Seong;Kang, Bu Sik
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.12 no.3
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    • pp.139-151
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    • 1992
  • A reservoir operation model was established under the varying restricted water level(r.w.l.) subject to the inflow distributions in flood period. The optimization model consists of 2 sub-models. One model minimizes deviations of releases from the expected release and the other minimizes capacity requirement for flood control. In order to make deterministic equivalents, the inflow distribution of reservoir is assumed to be 2-parameter Lognormal, and its parameters are estimated by the maximum likelihood method. The model is applied to joint operation of Soyang and Chungju dam. The results show that Soyang was designed for larger flood event than that for Chungju. The operation under the varying r.w.l. turns out to be more effective than one under the uniform r.w.l. Such effect is more obvious at Chungju compared with Soyang. Release pattern shows diminishing and delaying effect in a period of high inflows and larger discharges than actual in a period of low inflows.

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Influence of perceived patient safety culture on patient safety management activity in the dental hygienists (치과위생사의 환자안전문화 인식이 환자안전관리활동에 미치는 영향)

  • Lee, Da-Jung;Han, Su-Jin
    • Journal of Korean society of Dental Hygiene
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    • v.16 no.6
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    • pp.863-877
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    • 2016
  • The study aimed to investigate the influence of perceived patient safety culture on patient safety management activity in the dental hygienists. Methods: A self-reported questionnaire was completed by 292 dental hygienists in Seoul, Incheon and Gyeonggido from March 1 to April 8, 2016. The questionnaire consisted of general characteristics of the subjects (9 items), patient safety culture (44 items), and patient safety management activity (25 items) by Likert 5 point scale. Data were analyzed by t test, one way ANOVA, stepwise multiple regression test, and post-hoc Tukey test using SPSS 18.0 program. Results: The perceived patient safety culture was 3.50 on average. Entire organization was the highest score (3.68) and followed the communication process (3.55), the environment of work unit (3.47), the attitude of supervisor/manager (3.45), and the frequency of events reported (2.98). The average of patient safety management activity was 3.71. As for the factors of patient safety culture on patient safety management activity, communication process was the most influential factor (${\beta}=0.268$), and followed the entire organization (${\beta}=0.265$), the environment of work unit (${\beta} =0.166$), the frequency of events reported (${\beta}=0.104$), and among the control variables. Work place proved to be the only significant variable. Conclusions: In order to promote patient safety management activity of dental institutions, the patient safety culture should be created and established. The influence of communication process and patient safety culture at entire organization level was huge. So the environment of work unit and the perceived patient safety culture in the process of reported events were influencing factors. The strategy for patient safety management activity should be considered because of low level of perceived patient safety culture.

Source Identification and Quantification of Coarse and Fine Particles by TTFA and PMF

  • Hwang, In-Jo;Bong, Choon-Keun;Lee, Tae-Jung;Kim, Dong-Sool
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.E4
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    • pp.203-213
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    • 2002
  • Receptor modeling is one of statistical methods to achieve reasonable air pollution strategies. In order to maintain and manage ambient air quality, it is necessary to identify sources and to apportion its sources for ambient particulate matters. The main purpose of the study was to survey seasonal trends of inorganic elements in the coarse and fine particles. Second, this study has attempted emission sources qualitatively by a receptor method, the PMF mo-del. After that. both PMF (positive matrix factorization) model and TTFA (target transformation factor analysis) model were applied to compare and to estimate mass contribution of coarse and fine particle sources at the receptor. A total of 138 sets of samples was collected from 1989 to 1996 by a low volume cascade impactor with 9 size fraction stages at Kyung Hee University in Korea. Sixteen chemical species (Si, Ca, Fe, K, Pb, Na, Zn, Mg, Ba, Ni, V, Mn, Cr, Br, Cu. Co) were characterized by XRF. The study result showed that the weighted arithmetic mean of coarse and fine particles were 51.3 and 54.4 $\mu\textrm{g}$/㎥, respectively. Contribution of both particle fractions were esti-mated using TTFA and PMF models. The number of estimated sources was seven according to TTFA model and 8 according to PMF model. Comparison of TTFA and PMF revealed that both methodologies exhibited similar trends in their contribution pattern. However, large differences between contributions were observed in some sour-ces. The results of this study may help to suggest control strategies in local countries where known source profiles do not exist.

Evolutionary Optimization of Pulp Digester Process Using D-optimal DOE and RSM

  • Chu, Young-Hwan;Chonghun Han
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.395-395
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    • 2000
  • Optimization of existing processes becomes more important than the past as environmental problems and concerns about energy savings stand out. When we can model a process mathematically, we can easily optimize it by using the model as constraints. However, modeling is very difficult for most chemical processes as they include numerous units together with their correlation and we can hardly obtain parameters. Therefore, optimization that is based on the process models is, in turn, hard to perform. Especially, f3r unknown processes, such as bioprocess or microelectronics materials process, optimization using mathematical model (first principle model) is nearly impossible, as we cannot understand the inside mechanism. Consequently, we propose a few optimization method using empirical model evolutionarily instead of mathematical model. In this method, firstly, designing experiments is executed fur removing unecessary experiments. D-optimal DOE is the most developed one among DOEs. It calculates design points so as to minimize the parameters variances of empirical model. Experiments must be performed in order to see the causation between input variables and output variables as only correlation structure can be detected in historical data. And then, using data generated by experiments, empirical model, i.e. response surface is built by PLS or MLR. Now, as process model is constructed, it is used as objective function for optimization. As the optimum point is a local one. above procedures are repeated while moving to a new experiment region fur finding the global optimum point. As a result of application to the pulp digester benchmark model, kappa number that is an indication fur impurity contents decreased to very low value, 3.0394 from 29.7091. From the result, we can see that the proposed methodology has sufficient good performance fur optimization, and is also applicable to real processes.

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Comparison of Kinematic Variables of the Elite Woman's 100m Hurdler (엘리트 여자 100m 허들선수들의 운동학적 변인 비교)

  • Ryu, Jae-Kyun;Chang, Jae-Kwan;Yeo, Hong-Chul;Lim, Jung-Woo
    • Korean Journal of Applied Biomechanics
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    • v.17 no.4
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    • pp.149-156
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    • 2007
  • The purpose of this study was to compare the world class women's hurdlers with kinematic variables Lee Yeon-Kyoung's in the 100m hurdle. Among korea elite female hurdler, Lee Yeon-Kyoung was participated as a subject. Eight JVC video cameras(GR-HD1KR) were used to film the performance of Lee Yeon-Kyoung at a frame rate of 60fields/s. The real-life three-dimensional coordinate data of digitized body landmarks were smoothed using a fourth order Butterworth low pass recursive digital filter with an estimated optimum cutoff frequency of 7.4Hz. After analyzing and comparing Lee Yeon Kyung's kinematic variables with the world top class hurdlers in the woman's 100m hurdle run, the following conclusions were obtained. 1. Lee should be able to increase the speed with over 5.4m/s from start to first hurdle and then maintain the speed range from 8.33m/s to 8.67m/s until 10th hurdle. Lee should have to maintain the speed with 8.51m/s from 10th hurdle to finish line. 2. Lee has to reach her maximum running speed at 5th hurdle and then has to shorten running time with 0.5sec between hurdles. 3. Lee should be able to run around 2.5sec from start to frist hurdle and then maintain under 1.00sec following phases. Lee should be able to maintain under 1.10sec from 10th hurdle to finish line. 4. Lee needs to control a consistent takeoff and landing distance pattern, Lee needs to lower the height of the center of gravity of the body with 0.33m when she clears the hurdles.

Calibration and Performance Test of Hot-wire Anemometers by Using a Calibration Wind Tunnel (풍동장치를 이용한 열선풍소계의 보정 및 실태 평가)

  • Ha, Hyun-Chul;Kim, Tae-Hyeung;Kim, Eun-A;Kim, Jong-Chul;Oh, Jung-Ryng;Jung, Ho-Keun
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.9 no.2
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    • pp.110-122
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    • 1999
  • Hot-wire anemometers are most commonly used in measuring hood capture velocities due to their accuracy and convenience. But it was questionable that the anemometers being used in the field are accurate enough for the purpose of measurements. To answer this ques tion, a calibration wind tunnel was newly devised and tested. Subsequently, 53 hot-wire anemometers being currently used in the field were tested to evaluate the accuracy of anemometers. The average error was 16.93% while the average errors in the low (0.5~5m/s) and high (5~20m/s) velocity range were 17.40% and 16.45%, respectively. Most of anemometers underestimated the true velocities. It might be due to the contamination of hot-wire, resulting in the slow heat transfer between the sensor and air flow. Astonishingly, 16 of 53 anemometers were out of order due to the malfunctioning of zero adjustment control, power supply, display panel and sensor. It is desirable to calibrate periodically and clean the sensor after using in the dirty environment.

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Techniques for Estimating Temper Bead Welding Process by using Temperature Curves of Analytical Solution (해석 해의 온도곡선을 이용한 템퍼비이드 용접공정 평가기술)

  • Lee, Ho-Jin;Lee, Bong-Sang;Park, Kwang-Soo;Byeon, Jin-Gwi;Jung, In-Chul
    • Journal of Welding and Joining
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    • v.28 no.5
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    • pp.51-57
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    • 2010
  • Brittle microstructure created in a heat affected zone (HAZ) during the welding of low alloy steel can be eliminated by post-weld heat treatment (PWHT). If the PWHT is not possible during a repair welding, the controlled bead depositions of multi-pass welding should be applied to obtain tempering effect on the HAZ without PWHT. In order to anticipate and control the tempering effect during the temper bead welding, the definition of temperature curve obtained from the analytical solution was suggested in this research. Because the analytical solution for heat flow is expressed as a mathematical equation of weld parameters, it may be effective in anticipating the effect of each weld parameter on the tempering in HAZ during the successive bead depositions. The reheating effect by the successive bead layer on the brittle coarse grained HAZ formed by earlier bead deposition was estimated by comparing the overlapped distance between the temperature curves in the HAZ. Three layered weld specimens of SA508 base metal with A52 filler were prepared by controlling heat input ratio between layers. The tempering effect anticipated by using the overlapped distance between the temperature curves was verified by measuring the micro-hardness distribution in the HAZ of prepared specimens. The temperature curve obtained from analytical solution was expected as a good tool to find optimal temper bead welding conditions.