• Journal of Communications and Networks
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• v.11 no.4
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• pp.350-358
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• 2009

In a wireless sensor network (WSN) setting, this paper presents a distributed decision-making framework and illustrates its application in an online structural health monitoring (SHM) system. The objective is to recover a damage severity vector, which identifies, localizes, and quantifies damages in a structure, via distributive and collaborative decision-making among wireless sensors. Observing the fact that damages are generally scarce in a structure, this paper develops a nonlinear 0-norm minimization formulation to recover the sparse damage severity vector, then relaxes it to a linear and distributively tractable one. An optimal algorithm based on the alternating direction method of multipliers (ADMM) and a heuristic distributed linear programming (DLP) algorithm are proposed to estimate the damage severity vector distributively. By limiting sensors to exchange information among neighboring sensors, the distributed decision-making algorithms reduce communication costs, thus alleviate the channel interference and prolong the network lifetime. Simulation results in monitoring a steel frame structure prove the effectiveness of the proposed algorithms.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2000.05a
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• pp.22-27
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• 2000

This Paper decribes a monitoring system using Modbus protocol and RS485 interface applied in many industrial field. We developed hardware to receive alanlog sensor output and monitoring program to communicate with hardware and carried out experiment with potentiometer for plan sensor, . Through online communication between Master and Slaves we convinced the usage of this systems. Also plant data file that saved in Excel format is convenient in writing various typs of documents.

• Proceedings of the Korean Society of Laser Processing Conference
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• 2005.11a
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• pp.46-49
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• 2005

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.2
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• pp.103-111
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• 2002

Out of all metal-cutting process, the hole-making process is the most widely used. It is estimated to be more than 30% of the total metal-cutting process. It is therefore desirable to monitor and detect drill wear during the hole-drilling process. One important aspect in controlling the drilling process is monitoring drill wear status. There are two systems, Basic system and Online system, to detect the drill wear. Basic system comprised of spindle rotational speed, feed rates, thrust torque and flank wear measured by tool microscope. Outline system comprised of spindle rotational speed feed rates, AE signal, flank wear area measured by computer vision, On-line monitoring system does not need to stop the process to inspect drill wear. Backpropagation neural networks (BPNs) were used for on-line detection of drill wear. The output was the drill wear state which was either usable or failure. This paper deals with an on-line drill wear monitoring system to fit the detection of the abnormal tool state.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.2110-2111
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• 2008

Continuous on-line temperature monitoring allows corrective measures to be taken to prevent upcoming failure. Continuous temperature monitoring and event recording provides information on the energized equipment's response to normal and emergency conditions. On-line temperature monitoring helps to coordinate equipment specifications and ratings, determine the real limits of the monitored equipment and optimize facility operations. Using wireless technique eliminates any need for special cables and wires with lower installation costs if compared to other types of online condition monitoring equipment. In addition, wireless temperature monitoring works well under difficult conditions in strategically important locations. Wireless technology for on-line condition monitoring of energized equipment is applicable both as standalone system and with an interface with power quality monitoring system.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1974-1975
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• 2007

Continuous temperature monitoring and event recording provides information on the energized equipment's response to normal and emergency conditions. On-line temperature monitoring helps to coordinate equipment specifications and ratings, determine the real limits of the monitored equipment and optimize facility operations. Using wireless technique eliminates any need for special cables and wires with lower installation costs if compared to other types of online condition monitoring equipment. In addition, wireless temperature monitoring works well under difficult conditions in strategically important locations. Wireless technology for on-line condition monitoring of energized equipment is applicable both as standalone system and with an interface with power quality monitoring system. The paper presents the results of wireless temperature monitoring of switchgear at a power plant over a two-year period.

• Korean Journal of Health Education and Promotion
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• v.33 no.5
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• pp.71-81
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• 2016

Objectives: Tobacco marketing encourages smoking initiation of non-smokers, especially adolescents, and it hinders quit intention of those who smoke or who attempt to quit smoking. Article 13 of the WHO Framework Convention on Tobacco Control(WHO FCTC) requests a comprehensive ban on tobacco advertising, promotion and sponsorship(TAPS). Ratified the Convention in 2005, Korea has partially implemented the provisions. However, online marketing regulations are still insufficient. Methods: Based on relevant national and international regulations, this research designed monitoring mechanism for online tobacco marketing and studied 1,404 websites to identify current situation of online sales and advertisement of tobacco in Korea. Results: This study found that online trade of tobacco products are overtly conducted, while tobacco advertising with flavoring and misleading descriptors are also prevalent. Also, online tobacco marketing facilitate adolescents' access to tobacco product and that advertising and promotion activities lead to tobacco purchase without difficulties. Conclusions: Fundamental solution to prevent online tobacco advertisement and promotion is banning online sales of tobacco and conducting a regular monitoring for compliance. Korean government should consider establishing an official surveillance system for online tobacco advertisement, followed by a comprehensive ban on TAPS to fulfill its obligation as a Party to the FCTC.

• Journal of Korean Public Health Nursing
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• v.34 no.3
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• pp.405-415
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• 2020

Purpose: This study was undertaken to identify the mediating effect of family strengths in the relationship between e-learning readiness and learning management system-based online education learning outcomes. Our results provide basic data for proposing strategies to increase online education learning outcomes of nursing students. Methods: A self-report questionnaire was surveyed by 133 nursing students who took online education using a learning management system at three nursing colleges in Daejeon, Jeonbuk, and Gyeongbuk. The mediating effect of family strengths in the relationship between the e-learning readiness of the subject and online education learning outcomes, were analyzed by hierarchical multiple regression. Sobel test was performed to verify effectiveness of the pathway. Results: In the relationship between e-learning readiness and online education learning outcomes of nursing students, family strengths were determined to exert absolute mediating effect. Conclusions: Our results indicate that in order to improve e-learning readiness, the basic curriculum for nursing students should include web-based communication, cooperation, and the use of information technology, including interaction for online education. Improvements in family strengths can be achieved through home study activities, such as frequent conversations with members, monitoring achievements of the students, and sharing family leisure activities.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.12
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• pp.54-60
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• 2000

Research about tool condition monitoring has been done until now for product automation and unmaned system. But it is hard to apply it to the industrial field due to its cost and reliability. This paper presents the new method of tool wear measurement using Marpos gauge. This is a kind of touch sensor, so its cost is lower than vision system. And it is not affected by dust and illumination, which are important in vision system. This proposed method use tool clearance angle to measure flank wear. Experimental results compared with vision system shows that this method is available for tool condition monitoring system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.478-479
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• 2007

With increasing interest in the reduction of cost for operation and maintenance of overhead catenary system, various methods of condition monitoring have been developed. In this paper, we proposed network-based telemetry system for condition monitoring in railway and acquired data from any kind of sensor in catenary line and structure at high voltage. This development gives the solution for online condition monitoring in railway. To check the validity of our approach in terms of application, we realized network-based telemetry System.