• Current Applied Physics
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• v.18 no.11
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• pp.1388-1392
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• 2018

Metal thin films are used widely to solve the vibration problem. However, damping mechanism is still not clear, which limits the further improvement of the damping properties for film and the development of multi-functional damping coating. In this paper, Damping microscopic mechanism of porous metal films was investigated at both macroscopically and microscopically mixed levels. Molecular dynamics simulation method was used to model and simulate the loading-unloading numerical experiment on the micro-pore and vacancy model to get the stress-strain curve and the microstructure diagram of different defects. And damping factor was calculated by the stress-strain curve. The results show that dislocations and new vacancies appear in the micro-pores when metal film is stretched. The energetic consumption from the motion of dislocation is the main reason for the damping properties of materials. Micro-mechanism of damping properties is discussed with the results of in-situ experiment.

• Journal of Drive and Control
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• v.17 no.1
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• pp.37-43
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• 2020

An intelligent excavator can be divided into Machine Guidance (MG), semi-automatic, and unmanned by technology. The MG technology excavator is equipped with a tilt sensor on each link of the excavator and a GPS is installed on the excavator body to inform the user of the position of the excavator bucket end. Machine control (MC) technology that assists the user's work can be divided into semi-automatic and fully automatic technology. The semi-automatic MC equipment has already been commercialized by Komatsu and Caterpillar. The MC excavator is equipped with an electro-hydraulic system, sensors and controllers to control the excavator bucket end according to the user's needs. In this study, the semi-automated excavator modified based on manual excavator, is equipped with an electro-hydraulic system, a controller system, multi-sensors and a control algorithm is developed to assist in excavation work such as leveling and grading. By applying the developed technology, it was possible to confirm productivity improvement compared to manual digging and leveling work. In the future, further research to improve the accuracy of the hydraulic precision control and collaborative work with heterogeneous construction equipment such as dump truck and automated collaboration tasks technology could be developed.

• Proceedings of the KIEE Conference
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• 2007.04a
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• pp.143-145
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• 2007

The development of excitation control system (ECS) for emergency diesel generator in nuclear power plant is the replacement project of existing control system to resolve the maintenance problems caused by aging and obsolescence, The excitation control system is classified as a safety-related system. To guarantee the performance of developing excitation control system is equal to or higher than that of other systems, establishing the quality assurance scheme, doing software verification and validation activities, and planning equipment qualification. In this paper, we'd like to introduce the equipment qualification of excitation control system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.677-684
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• 2017

Smart devices are used in a variety of industries, because applications for them are easy to develop and portable. However, industrial equipment can cause security problems for information and accidents when controlling the actuator of the equipment at a remote location. In this paper, we studied methods of solving these problems and the advantages of applying smart control systems to industrial equipment. We propose a manual manipulation method using queries and a smart control access procedure for controlling equipment using a smart device. In addition, we propose a data transmission method employing multiple encryption protocols and a user authentication method using unique information from the smart device and Q & A as the communication data protection and user authentication methods, respectively. In order to evaluate its performance, an operation test of the smart control system and user authentication comparison experiment were performed. In order to understand the advantages of applying the smart control system to the equipment, we conducted a comparative experiment with a teach pendant and evaluated its reaction time in case of error.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.5
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• pp.703-712
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• 2014

To improve the efficiency and safety of railway systems, the train control system has been considerably evolved from the ground-equipment-based control system (e.g. track circuit, interlocking system, etc.) into the on-board-equipment-based control system. In addition, this train control system enables the rolling stock to intelligently control the trackside facilities by introducing the information and communication technologies (ICT). Accordingly, since the ICT-based train control system makes the railway system be simplified (i.e. the heavy ground-equipment can be removed), the efficient and cost-effective railway system can be realized. In this paper, we perform the feasibility test of the ICT-based train control system via a simulation. To this end, we have developed the prototypes of the on-board controller and wayside object control units which control the point and crossing gate and performed the integrated operation simulation in a testbed. In this paper, before the field test of the on-board-controller-based train control system, we perform the Consecutive operation test for prototypes of the on-board controller, wayside object control units and local control computer.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.291-298
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• 2000

This paper describes a theoretical and experimental investigation into an active vibration isolation system in which four electromagnetic actuators are installed in parallel with each of four passive mounts placed between a piece of equipment and a vibrating base structure. Decentralised velocity feedback control is employed, where each actuator is operated independently by feeding back the absolute equipment velocity at the same location. Although one end of each actuator acts at the sensor positions on the equipment, the control system is not collocated because of the reactive forces acting on the flexible base structure, whose dynamics are strongly coupled with the mounted equipment. Isolation of low frequency vibration is considered where the equipment can be modelled as a rigid body and the mounts as lumped parameter springs and dampers. Control mechanisms are discussed, and some experimental and simulation results are reported.

• KIEAE Journal
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• v.7 no.5
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• pp.73-80
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• 2007

Indoor climate control equipments is used to make the indoor environment more comfortable when indoor condition is not satisfactory to inhabitants. In this study, which instrument is preferred to control indoor climate and which is not preferred were surveyed with questionnaire. With this result, the needs of dwellers and wanting performance of housing could be revealed. Results are followings 1) The satisfaction ratio and equipment possession ratio of apartment houses' is higher than that of detached dwelling's 2) It is recognized for inhabitants that air cleaner is the mostly used equipment and best equipment for indoor comfort. 3) Electronic fomentation mat is recognized as the most problematic equipment for securing inhabitant's comfort. And air conditioner is considered negative for 60% of responser's. As grow older, this trend is increasing.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.803-804
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• 2016

With the advent of Germany's Industry 4.0, research of smart factory to applying the ICT in manufacturing industries is in progress. But the current system controlled equipment using the data declared in the embedded systems. In this paper, we proposed equipment control method to implement smart factory based on IoT. This method is create D/B table of data declared in equipment. and equipment shall call all of control unit parameters. When using the present method, it is possible to efficiently control the number of equipment as less network resource. Also It can operating a factory efficiently.

• Journal of Korean Clinical Nursing Research
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• v.16 no.2
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• pp.69-84
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• 2010

Purpose: The purpose of this study was to identify the state of infection control in neonatal intensive care units (NICUs) including disinfection methods, disinfection cycles, and exchange cycles for medical devices and to suggest a basic framework which would help develop standardized infection control guidelines. Methods: From a list of NICU equipment developed from the NICUs in 4 tertiary hospitals, a structured questionnaire on 74 types of medical equipment was developed and sent to 31 hospitals by mail. The results were reviewed by panel of experts (56 persons), and analyzed for internal validity by a focus group (4 persons) using guidelines from the Centers for Disease Control and the Korean Hospital Nurses Association. Results: The results showed various methods, cycles, disinfectant levels for the disinfectants and exchange cycles in the medical equipment infection control of the 31 hospitals. The focus group developed a 66-item basic framework based on validity testing. Conclusion: From the results of this study, a framework of infection control standards for 66 types of medical equipment in the NICU was developed. It is suggested that further study be done to more precisely establish standard infection control guidelines for NICU medical equipment.

• Journal of Industrial Technology
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• v.27 no.A
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• pp.61-67
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• 2007

The construction machine is the composite machine assembled by about 30,000 parts. Excavator, one kind of a construction machine, plays the leading role for export of construction equipment. It is generally impossible to produce all of the items within one company. Especially the supply of hydraulic control valves, one of the core part of the construction equipment, depends on the import heavily. So it is important to make an efficient production plan of hydraulic control valves in the company. The most important thing for the production scheduling of a hydraulic control valve is to make production schedule keeping the start date for assembly line for an excavator and to make minimization of the stock level. The production plan of hydraulic control valve includes the decision of the quantity supplied by subcontractor. This paper presents a scheme for a scheduling system of the hydraulic control valve considering the schedule of the assembly line for excavator production. This paper provides a methodology, which can make a plan of supply and production and generate a detailed schedule for daily production.