• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.5
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• pp.78-84
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• 2001

The translation system is made up of springs, masses and a dashpot. This precise piece of equipment is controlled electro-mechanically by a motor and operating program. The control strategy of the system can be changed by spring stiffness, change of mass, and the damping coefficient of the dashpot. This system proves the necessity and effect of a closed loop control. In this paper, PD control experiments were implemented for the translation system. When the north falter was added on the PD controller, we compared the response characteristics of the two systems. The state feedback controller minimized scalar control gains and the resulting response characteristics of the system were studied using the LQR design. Finally, we improved the response characteristics of the translation system which are rising time, settling time, steady state error, and overshoot LQR was better as compared with PD control.

• Structural Engineering and Mechanics
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• v.46 no.4
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• pp.549-569
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• 2013

A passive control using flaps will be an alternative solution for flutter stability and buffeting response of a long suspension bridge. This method not only enables a lightweight economic stiffening girder without an additional stiffness for aerodynamic stability but also avoid the problems from the malfunctions of control systems and energy supply system of an active control by winglets and flaps. A time domain approach for predicting the coupled flutter and buffeting response of bridge deck with flaps is investigated. First, the flutter derivatives of bridge deck and flaps are found by experiment. Next, the derivation of time domain model of self-excited forces and control forces of sectional model is reported by using the rational function approximation. Finally, the effectiveness of passive flap control is investigated by the numerical simulation. The results show that the passive control by using flaps can increase the flutter speed and decrease the buffeting response. The experiment results are matched with numerical ones.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.4_1
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• pp.397-409
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• 2021

This study proposes a new approach to implimentation of robust control and torque control response analysis based on monitoring simulator for smart factory. According to the physical properties of a flexible manipulator, a two time-scale approach, namely, singular perturbation ap proach, is further utilized for thorough analysis and general controller design. It is shown that asymptotic motional tracking can be effectively achieved, whereas the force regulation errors can be made arbitrarily small. For demonstration of the proposed technology performance, experiments of a eight joint flexible manipulator are performed for the proposed control method, and the reliability of proposed control results are illustrated based on monitoring simulator.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.323-325
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• 2009

In this paper, we present simulation results of Dynamic Matrix Control(DMC) to a boiler steam temperature. In order to control of steam temperature, we choose the input-output variables and generate the step response model by each input variable's step test. After that, the control structure executes on-line control with optimization using step response model. Proposed controller is applied to the APESS(Doosan company's boiler model simulator) and it is observed that the simulation results show satisfactory performance of proposed control.

• Journal of Korean Association for Spatial Structures
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• v.16 no.3
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• pp.107-115
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• 2016

In recent years, an outrigger damper system has been proposed to reduce dynamic responses of tall buildings. However, a study on outrigger damper system is still in its early stages. In this study, time history analysis was performed to investigate the dynamic response control performance of outrigger damper. To do this, a actual scale 3-dimensional tall building model with outrigger damper system has been developed. El Centro earthquake was applied as an earthquake excitation. The control performance of the outrigger damper system was evaluated by varying stiffness and damping values. Analysis results, on the top floor displacement response to the earthquake load, was greatly effected by damping value. And acceleration response greatly was effected by stiffness value of damper system. Therefore, it is necessary to select that proper stiffness and damping values of the outrigger damper system.

• Journal of Korean Academy of Nursing
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• v.31 no.6
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• pp.998-1011
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• 2001

In order to improve self-management of elderly hypertensives in this study, the researcher examined the effect of blood pressure regulation by an abdominal relaxed breathing training which regulates physical response to stress and lessens the activity of the sympathetic nerve. Method: A quasi-experimental pre-test and post-test design was used. Thirty elderly hypertensive patient ; Sixteen in the abdominal breathing group and fourteen in the control group participated in this study. The abdominal relaxed breathing training consisted of eight sessions twice a week for four weeks. There was no intervention for the control group. Result: 1. There was a significant decrease in systolic and diastolic blood pressure between the experimental group and control group over three different times, and interaction by groups and over time. 2. There was no significant difference in the level of total stress response, physical stress response, behavioral-cognitive stress response between the experimental group and control group over three different times, and interaction by groups and over time. Conclusion: Findings indicate that this study will contribute to develop nursing strategies for the regulation of blood pressure for the elderly, which is easy for the elderly to learn as a nonpharmacologic approach.

• Nuclear Engineering and Technology
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• v.51 no.7
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• pp.1791-1798
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• 2019

Instrumentation and Control (I&C) systems of nuclear power plants (NPPs) have been continuously digitalized. These systems have a critical role in the operation of nuclear facilities by functioning as the brain of NPPs. In recent years, as cyber security threats to NPP systems have increased, regulatory and policy-related organizations around the world, including the International Atomic Energy Agency (IAEA), Nuclear Regulatory Commission (NRC) and Korea Institute of Nuclear Nonproliferation and Control (KINAC), have emphasized the importance of nuclear cyber security by publishing cyber security guidelines and recommending cyber security requirements for NPP facilities. As described in NRC Regulatory Guide (Reg) 5.71 and KINAC RS015, challenge response authentication should be applied to the critical digital I&C system of NPPs to satisfy the cyber security requirements. There have been no cases in which the most robust response authentication technology like challenge response has been developed and applied to nuclear I&C systems. This paper presents a challenge response authentication mechanism for a Programmable Logic Controller (PLC) system used as a control system in the safety system of the Advanced Power Reactor (APR) 1400 NPP.

• The Journal of Pediatrics of Korean Medicine
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• v.8 no.1
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• pp.27-37
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• 1994

This Experimental study was done to investigate the effect of the Taklisodok-um on the Anti-allergic response. The results were obtained as follows: 1. On vascular permeability response to the intradermal injected Histamine, the Taklisodok-um treated group revealed more significant decrease than control group. 2. On vascular permeability response to the intradermal injected Serotonin, the Taklisodok-um treated group revealed more significant decrease than control group. 3. In the 48hrs homologous passive cutaneous anaphylaxis provoked by the IgE-like antibody against white egg albumin, there was no significant difference between the Taklisodok-um treated group and control group. 4. The Taklisodok-um treated group revealed more significant inhibitory effect than control group in the delayed type hypersensitivity response to Picryl chloride. 5. The Taklisodok-um treated group revealed more significant inhibitory effect than control group in the delayed type hypersensitivity response to SRBC. According to the above-stated results, it is considered that the Taklisodok-um could be applied widely to the type I and IV allergic diseases.

• Journal of Korean Academy of Nursing
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• v.36 no.5
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• pp.751-760
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• 2006

Purpose: This study was to evaluate the effects of a comprehensive life style modification program on glycemic control and stress response in type 2 diabetes. Method: The participants(n=34) with type 2 diabetes were divided into either a usual care(control) or treatment(experimental) group. The experimental group(n=21) received a program that was based on a comprehensive life style modification protocol at a weekly meeting for 16 weeks. They also participated in individually prescribed exercise and diet along with stress management and self monitoring. The participants were followed for 6 months, during which postprandial glucose, HbA$_{1C]$, and stress response inventory were measured. Result: The experimental group showed a significant lower postprandial glucose and stress response compared to those of the control group. However, there was no significant change in the HbA$_{1C]$ value in either group. Conclusions: These results suggest that a type 2 diabetes comprehensive lifestyle modification program may lead to clinical improvement in glycemic control and reduce the stress response.

• Journal of Environmental Health Sciences
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• v.46 no.5
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• pp.599-609
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• 2020

Objectives: Coronavirus disease 2019 (COVID-19) first emerged in December 2019 in Wuhan, China, and has rapidly become a global pandemic with over 26.4 million confirmed cases and approximately 871,000 fatalities worldwide as of this writing. In the Republic of Korea, disease clusters frequently occurred in long-term care hospitals where the majority of residents are elderly with underlying medical conditions. Despite the fact that public health authorities and local community health centers have put tremendous efforts into preventing the spread of disease, positive cases have continued to occur. Thus, the Korea Centers for Disease Control & Prevention rapid response team decided to conduct an environmental investigation of a long-term care hospital to identify whether environmental contamination has remained and contributed to the spread of COVID-19. Methods: An environmental investigation was conducted at Hospital A. The characteristics of the facility and its HVAC system were assessed by checking the layout and interviewing the people in charge. A total of 64 surface samples were collected from areas of concern, including patient rooms, toilets, elevators, and nurses' station. These samples were tested by a regional health and environmental research institute using real-time reverse transcription polymerase chain reaction. Results: All samples from Hospital A were confirmed to be negative. Through interviews with high-level personnel at the regional community health center, we found that extensive disinfection is frequently performed on potentially contaminated areas in Hospital A in accordance with government guidelines. Conclusion: The environmental control measures implemented in Hospital A had been sufficient for mitigating the risk of further infection, suggesting that such measures may also be effective for other long-term health care facilities.