• Journal of Institute of Control, Robotics and Systems
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• v.18 no.9
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• pp.801-805
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• 2012

This paper proposes dynamic thresholding scheme for fingerprint identification. As a user authentication method by fingerprint recognition technology, verification method based on 1:1 matching was mainly used in the past, but identification method based on 1:N matching is generally used recently. The control of the value of FAR is very important in the application areas such as access control and time attendance systems. This paper proposes dynamic thresholding scheme which could properly control the value of FAR according to the field of applications and size of the fingerprints database.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.538-541
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• 2005

Most realistic control systems contain nonlinearities of some form. One nonlinearity commonly found in control systems is a saturating element. If integral control is applied to such a system to eliminate steady state error, an undesired side effect known as integrator windup may occur when lage setpoint changes are made. This effect leads to a characteristic step response with a large overshoot and a very high settling time. To avoid this situation, many different anti-windup strategies have been suggested. But existing strategies remain over shoot and high settling time. This paper proposes a new anti-windup strategy for PI speed controllers. When the speed control system is changed P controller to PI controller. Integrator has an appropriate initial value. This value results over shoot and high settling time. The SIMULINK/MATLAB-based comparative simulation results and experiment results of speed controller have shown its superior control performance to that of a proposed anti-windup speed controller.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.8
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• pp.768-773
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• 2012

Packet loss compensation techniques are increasingly important to stable remote control over wireless communication in WNCS (Wireless Networked Control Systems). Its time varying channels, limited bandwidth, interference, and poor signal not only leads to packet loss or latency, but also can negatively affect performance and system stability. This paper presents a compensation technique exploiting an EWMA (Exponentially Weighed Moving Average)-based value estimator to clarify the influence of packet loss on the overall WNCS behavior. As an example of actuator to be remotely controlled, a rotary-type inverted pendulum has been considered, and modeled. Performance evaluation results through Matlab/Simulink and Truetime co-simulation confirm the superiority of the proposed value estimation method over previous approaches.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 1997.03a
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• pp.235-246
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• 1997

Hybrid fuzzy gain scheduling controller is composed of a PD control and a fuzzy control for taking the advantage of each scheme. The key structure of the hybrid fuzzy gain scheduling control scheme is so called a switch which calculates weighting values between the fuzzy controller and the PD controller. However, due to the requirement of the switch , the hybrid fuzzy gain scheduling control scheme needs extra fuzzy logic processing, thus the structure is complicated. and requires more calculation time. To eliminate the drawbacks, a new hybrid fuzzy gain scheduling control scheme is proposed in this paper. In the proposed scheme, the membership function, for calculating of weithting value, and the input and output membership functions are combined. Thus the proposed hybrid scheme does not require switch for calculation of weighting value, and as a result, the calculation time is faster and the structure is more simple than the existing hybrid controller. Computer simulation results for an inverted pendulum model under Pole-Placement PID controller, fuzzy gain scheduling controller,existing hybrid controller , and proposed hybrid controller are compared to demonstrate the good property of the proposed hybrid controller.

• IEMEK Journal of Embedded Systems and Applications
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• v.16 no.6
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• pp.285-292
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• 2021

Autonomous vehicles are divided into an upper controller that calculates control value through cognitive judgment and a lower controller that appropriately transmits its control value to an actuator. Here, the longitudinal control in a lower controller has a problem as the road slopes due to the property of the Acceleration sensor to output the acceleration as the slope of the device. Therefore, in this paper, a sigmoid function is proposed to determine the slope to compensate for this problem. Through the experiment, Checked performance by comparing the existing table model with the proposed model.

• Research in Community and Public Health Nursing
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• v.10 no.1
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• pp.204-226
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• 1999

This study attempted to compare the social interest, motivation, and attitude of nursing college students who participated in a voluntary program and the students who didn't participate in a voluntary program. The purpose of this study can be summarized as to find the effect of a voluntary program and to offer fundamental data for institutionalizing a voluntary program in college. The subjects were composed of two groups, one group attend the voluntary program and the other group doesn't. The subjects were 390 nursing students: 179 in the experimental group and 211 in the control group. The results of this study are as follows : 1. Before voluntary activities, the mean value of the control group was higher than that of the experimental group in social interest and altruistic motivation. The difference is statistically meaningful(t= -2.2.53, p=.25, t= -2.509, p= .013). 2. After voluntary activities, selfish motivation and altruistic motivation in the experimental group was higher than before. The difference is statistically meaningful(t= 2.404, p=.0l7, t=-2.751, p=.007). 3. The social interest, selfish motivation, altruistic motivation toward voluntary activities and selfish attitude, altruistic attitude toward voluntary activities will not have changed in the control group before or after voluntary program. However, the altruistic attitude lowered after voluntary activity. It is statistically meaningful(t=2.694, p=.008). 4. After the voluntary activities, there was a significant difference between the experimental and control groups in altruistic attitude. In the experimental group, the mean value of altruistic attitude increased significantly, but in the control group the mean value of altruistic attitude decreased ( t = 2.15, p = .032). The results of this study showed that voluntary activities not only increase social interest and altruistic attitude, but also the subject's understanding toward the community. 3. The social interest, selfish motivation, altruistic motivation toward voluntary activities and selfish attitude, altruistic attitude toward voluntary activities will not have changed in the control group before or after voluntary program. However, the altruistic attitude lowered after voluntary activity. It is statistically meaningful (t=2.694. p=.008). 4. After the voluntary activities, there was a significant difference between the experimental and control groups in altruistic attitude. In the experimental group, the mean value of altruistic attitude increased significantly, but in the control group the mean value of altruistic attitude decreased (t = 2.15, p =.032). The results of this study showed that voluntary activities not only increase social interest and altruistic attitude, but also the subject's understanding toward the community.

• Journal of Korean Association for Spatial Structures
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• v.18 no.2
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• pp.35-42
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• 2018

The outrigger damper system is a structural system with excellent lateral resistance when a wind load occurs. However, research on outrigger dampers is still in its infancy. In this study, dynamic response control performance of damper is analyzed according to change of stiffness value and damping value of damper. To do this, a real-scale 3D model of 50 stories has been developed and the artificial wind load has been entered for dynamic analysis. Generally, the larger the damping value, the smaller the stiffness value is, the more effective it is to reduce the maximum displacement and acceleration response. However, the larger the attenuation value as the cost of construction increases, it is necessary to select appropriate stiffness and damping value when applying an outrigger damper.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.699-705
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• 2020

This study aims to examine the antecedent factors of debt policy on the influence of firm growth on firm value. There was a total of 19 companies involved accounting for 95 observational data from a population of 169 companies listed on the Kompas 100 Index of the Indonesia Stock Exchange from 2014 to 2018. The data were analyzed through descriptive statistics, classic assumption tests, multiple regression, and hypothesis testing. The results prove that the firm growth, proxied by asset growth or sales growth, did not have a significant influence on the debt policy. Further, there was no significant influence of debt policy on firm value when using debt ratio and also dividend policy as a control variable. In contrast, there was a positive and significant influence on the firm value when using debt to equity ratio proxy, both with or without using the control variable. Therefore, the debt policy was not proven as an antecedent on the influence of firm growth on firm value. This finding implies that there was a tendency for the company management to adopt the policy, which would increase the debt ratio to increase the investors' confidence in the stock market and investors neglect the company's dividend policy.

• Journal of Korean Academy of Nursing
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• v.5 no.2
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• pp.1-10
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• 1975

Every patient, who enters the hospital has a potential for becoming anxious. The control of hospitalization anxiety experienced by hospital patients is considered to be an important factor in the process of recovery from illness. This study was conducted to investigate the relationship between informativeness and hospitalization anxiety in order to give basic data for psycho-social aspect of nursing care for hospitalized patients. One hundred patients admitted to Kyungpook National University Hospital during the period of Jan. to June 1975 were sampled and divided into two groups; fifty of experimental and fifty of control group. The set of informations prepared by the investigator were given additionally to experimental group while the control group only received routine informations. Both groups were rated according to the Hospitalization Informativeness Scale which consisted of 24 questionaries and 4 categories and Hospitalization Anxiety Scale one or two days prior to discharge from the hospital. The results of the study were as follows; 1 . Mean values of Hospitalization Informativeness Scale revealed significant differences at 0.01 level with experimental group showing higher mean value. Age, sex ana educational states aid not influence the mean values of Hospitalization Informativeness Scale in both groups. 2 . The length of hospitalization did not influence significantly on the mean value of Hospitalization Informativeness Scale in both groups. 3. Rank difference correlation coefficiently between mean value of Hospitalization Informativeness Scale and the importance of information the patient's perceived were revealed significant at 0.01 level in all 4 categories such as admission discharge, treatment and nursing activities, diagnostic test, diagnosis and prognosis, health teaching for the patient and family in experimental group. While, only two categories such as treatment and nursing activities and health teaching for the patient and family in control group were revealed significant correlation. 4. Mean value of Hospitalization Anxiety Scale revealed significant difference at 0.05 level with the experimental group showing lower Hospitalization Anxiety Scale. 5. Correlation coefficiently between Hospitalization Informativeness Scale and Hospitalization Anxiety Scale were revealed significant at 0.01 level in experimental group but there was no significant correlation in control group.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.3 no.1
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• pp.11-21
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• 1999

The effect of sulfite on barley seedlings was investigated through Chl content, the electron transport activity of the photosystem, and Chl fluorescence. Barley leaves were harvested every 12 hrs during greening periods, and were then treated with a sulfite solution in either light or dark conditions. In both cases, the Chl content decreased in comparison with the control at any greening period. After sulfite treatment in the light, the activity of PS I decreased slightly, yet that of PSII showed a decrease of about 15%. The values of Fv, qP and qE decreased, however, the value of ql increased compared with the control. In addition, the value of qE decreased in leaves greened more than 12 hrs compared with that of the control. This indicates that the photosynthetic complex involved in energy dependent fluorescence quenching is undeveloped in a 12 hrs greened leaf, accordingly, it was a hardly affected by sulfite. After sulfite treatment in the dark, the activities of PSII and PSI decreased slightly, there was a small change in the value of Fv, qP decreased, and qE and the ratio of qNP/q increased in comparison with the control. As a result, PSII and PSI were not inhibited, however, the redox of QA was inhibited, and the excited energy was lost through the nonphotochemical pathway. The effects of sulfite in light or dark conditions were not considerably different with the Chl fluorescence quenching analysis method. In both light and dark conditions, the value of qP significantly decreased with sulfite compared to that of the control. This implies that the redox of QA was inhibited by sulfite in both light and dark contions.