• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.270-272
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• 2005

In this paper, we proposed a new method detecting actions of some components driven by the coil excitation. Nuclear power reactors are typically controlled by the movement of several neutron-absorbing control rods into or out of the reactor core. For moving control rods, we use an electromagnetic-jack-typed mechanism, which is called Control Rod Drive Mechanism. This mechanism moves control rods by the step composed of sequential actions of components. In case any mechanical problems happen in the mechanism, the orders for the control rod movement from the higher system cannot be performed properly. This abnormal state must be monitored and the sequential actions of the components can be the monitoring target. The actions of components generate some deviations in the profiles of the currents flowing into the coils in the mechanism. We focused on this phenomena and devised a new method of detecting the actions of the components in Control Rod Drive Mechanism by using the wavelet transform for observing the current profile.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.1087-1095
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• 2020

The research purpose of the article is to evaluate the effects of the internal control components on the effectiveness of internal control of transport construction enterprises in Vietnam, on the basis of which we made recommendations to contribute to improving the effectiveness of internal control. Sample was collected from Vietnamese medium and large transport construction enterprises, the total number of sample questionnaires sent was 400, 330 filled-up questionnaires was collected and 250 was used for the study purpose. Quantitative research method was used for the study with the help of the SPSS software. The variables in the model are as follows: the dependent variable is the effectiveness of internal control, 5 independent variables are: control environment, risk assessment, control activities, communication, and monitoring. The results of the analysis explain 80.4% variation as a result of the effect of internal control on the Vietnamese transport construction enterprise. All five components positively affect the effectiveness of internal controls in the order of influence, which are: control activities, control environment, communication, risk assessment and monitoring. This study contributes in providing more empirical evidence about the effects of internal control components on the effectiveness of internal control of transport construction enterprises in Vietnam. The study has proposed a number of recommendations to help transport construction enterprises improve control activities and contribute towards improving the effectiveness of internal control.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.4
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• pp.35-41
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• 2014

Real-life time series characteristic data has significant amount of non-stationary components, especially periodic components in nature. Extracting such components has required many ad-hoc techniques with external parameters set by users in a case-by-case manner. In this study, we used Empirical Mode Decomposition Method from Hilbert-Huang Transform to extract them in a systematic manner with least number of ad-hoc parameters set by users. After the periodic components are removed, the remaining time-series data can be analyzed with traditional methods such as ARIMA model. Then we suggest a different way of setting control chart limits for characteristic data with periodic components in addition to ARIMA components.

• ETRI Journal
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• v.41 no.6
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• pp.838-849
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• 2019

We present a permanent magnet-based spherical wheel motor that can be used in omnidirectional mobility applications. The proposed motor consists of a ball-shaped rotor with a magnetic dipole and a hemispherical shell with circumferential air-core coils attached to the outer surface acting as a stator. Based on the rotational symmetry of the rotor poles and stator coils, we are able to model the rotor poles and stator coils as dipoles. A simple physical model constructed based on a torque model enables fast numerical simulations of motor dynamics. Based on these numerical simulations, we test various control schemes that enable constant-speed rotation along arbitrary axes with small rotational attitude error. Torque analysis reveals that the back electromotive force induced in the coils can be used to construct a control scheme that achieves the desired results. Numerical simulations of trajectories confirm that even without explicit methods for correcting the rotational attitude error, it is possible to drive the motor with a low attitude error (<5°) using the proposed control scheme.

• Journal of Ginseng Research
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• v.21 no.3
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• pp.174-186
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• 1997

In this study, rat hepatocytes known to have active carbohydrate metabolism were obtained by using the liver perfusion technique to examine the hypoglycemic action of red ginseng saponin components [ginsenoside (mixture, $Rb_1$, and $Rg_1$)] and incubated in two different media-one containing insulin and glucagon (control group), and the other containing glucagon only, The specific activities of some regulatory enzymes such as glucokinase, glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, and glucose 6-phosphatase, in main pathways which were directly related to the glucose metabolism were compared between these two kinds of hepatocytes cultured in two different media. The effects of red ginseng saponin components [ginsenoside (mixture, $Rb_1$, and $Rg_1$)] under the concentration of $10^3$~$10^6$% on these enzymes In hepatocytes were also investigated, when they were added to these two media. The results were as follows. The specific activity of enzymes such as glucokinase, glucose 6-phosphate dehydrogenase, and 6-phosphogluconate dehydrogenase related to glucose-consuming pathways of insulin-deficient group was much less than control one, however, their decreased activity was recovered after the addition of ginseng components at all range of concentrations. The increased specific activity of these on - zymes was shown by the addition of ginseng components to the control group. On the other hand, the specific activity of glucose 6-phosphatase related to glucose-producing pathway of insulin-deficient group was much higher than control one, but their Increased activity was decreased after the addition of ginseng components at all range of concentrations. The same results were obtained after the addition of ginseng components to the control group. These results suggest that the red ginseng saponin components might better diabetic hyperglycemia by regulating the activity of enzymes related to glucose metabolism directly and/or Indirectly though more detailed studies were needed.

• Journal of Korean Society of Forest Science
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• v.108 no.1
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• pp.21-28
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• 2019

This study was conducted to determine the carbon (C) and nitrogen (N) response of litterfall components as affected by N addition in compound fertilizer in a Korean red pine (Pinus densiflora S. et Z.) stand in southern Korea. Litterfall in a mature red pine stand was collected for two years following compound fertilizer application ($N_3P_4K_1$; $P_4K_1$) and no fertilization (control). The C concentration of litterfall components was not significantly (P > 0.05) different between the $N_3P_4K_1$ and the control plots, whereas the N concentration of the litterfall components was significantly higher in the $N_3P_4K_1$ plot than in the control plot. The $N_3P_4K_1$ and $P_4K_1$ additions induced a lower C/N ratio of litterfall components compared with the control plot. Annual C and N fluxes via litterfall components were not affected by the $N_3P_4K_1$ addition over the study period, except for reproduction litter. Annual N fluxes via reproduction litter were significantly higher in the $N_3P_4K_1$ plot than in the control plot. Thus, the $N_3P_4K_1$ and $P_4K_1$ additions could modify differently nutrient distribution of the forest floor and mineral soils in a red pine stand. These results indicate that N concentration and C/N ratio in litterfall components are more susceptible to fertilizer application than the C response in litterfall components.

• Journal of Mechanical Science and Technology
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• v.17 no.12
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• pp.1844-1854
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• 2003

This paper discusses details of modeling and robust control of an AMB (active magnetic bearing) spindle, and part I presents a modeling and validation process of the AMB spindle. There are many components in AMB spindle : electromagnetic actuator, sensor, rotor, power amplifier and digital controller. If each component is carefully modeled and evaluated, the components have tight structured uncertainty bounds and achievable performance of the system increases. However, since some unknown dynamics may exist and the augmented plant could show some discrepancy with the real plant, the validation of the augmented plant is needed through measuring overall frequency responses of the actual plant. In addition, it is necessary to combine several components and identify them with a reduced order model. First, all components of the AMB spindle are carefully modeled and identified based on experimental data, which also render valuable information in quantifying structured uncertainties. Since sensors, power amplifiers and discretization dynamics can be considered as time delay components, such dynamics are combined and identified with a reduced order. Then, frequency responses of the open-loop plant are measured through closed-loop experiments to validate the augmented plant. The whole modeling process gives an accurate nominal model of a low order for the robust control design.

• The Journal of Korean Physical Therapy
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• v.11 no.3
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• pp.23-36
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• 1999

The very definitions of posture and balance have changed, as has our understanding of the underlying neural mechanisms, In rehabilitation science, there awe at least two different conceptual theories to describe the neural control of posture and balance : the reflex/hierarchical theory and system theory. A reflex/hierarchical theory suggests the posture and balance result from hierarchically organized reflex responses triggered by independent sensory systems. The systems approach suggests that action emerges from an interaction of the individual with the task and environment. That is to say, the systems approach implies that the ability to control our body's position in space emerges from a complex interaction of musculoskeletal and neural systems, collectively referred to as the postural control system. The specific organization of postural systems determined both by the functional task and the environment in which it is being performed, The postural control system is divided into three basic functional components for assessment : 1) musculoskeletal components, 2) motor coordination components, and 3) sensory organization components. It is proposed that a systemic functional understanding of human balance is critical to effective programs for balance rehabilitation. Thus, this article briefly reviews the basic functional components to consider in designing treatment plan and for the benefit of the balance assessment.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.3
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• pp.217-224
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• 2015

This study aimed to investigate the effects of Dandelion (Taraxzcum coreanum) supplementation on milk yield, milk composition and blood characteristics in lactating dairy cows. Eight lactating dairy cows were divided into two groups (control: TMR supplementation, treatment: TMR with Dandelion supplementation). The milk yield, milk fat, lactose, solids not fat (SNF) and somatic cells counts (SCC) were not significantly different between the control group and the treatment group, whereas milk protein, milk urea nitrogen (MUN) and free fat acid (FFA) were significantly higher in the treatment group compared to the control (p<0.05). The blood components of the treatment group were compared with those of the control group and only aspartate aminotransferase (AST) appeared significantly high (p<0.05). The other blood components were not significantly different in the two groups. Blood corpuscle components in the groups were not significantly different. Especially, all blood corpuscle components in the treatment group were within the normal range. However, the white blood cells (WBC), lymphocytes (LYM) and hematocrits (HCT) in the control group exceeded the normal range. Based on the above results, the addition of Dandelion to feed increased milk protein, MUN and FFA, but did not significantly affect the composition of the blood and corpuscle in Holstein milking cows.

• Journal of Drive and Control
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• v.9 no.3
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• pp.1-7
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• 2012

This paper deals with the issue of model reference adaptive control strategy to control the injection molding machine. Prior to controller design, a pair of transfer functions are derived for the injection and dwelling process based on mathematical models of components. As external disturbances to examine the robustness of the proposed controller, nozzle clogging and contraction of molded objects are considered and realized by proportional valve. The overall simulation system, consisting of hydraulic components, controller and sensors, is implemented using the components of commercial software SimulationX. The simulation results confirm the proposed scheme's efficiency and robustness.