• Composites Research
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• v.12 no.4
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• pp.62-70
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• 1999

It was well recognized that damages associated mainly with the aging of civil infrastructrues were one of very serious problems for assurance of safety and reliability. In recent, carbon fiber sheet(CFS) has been widely used for reinforcement and rehabitation of damaged concrete beam. However, the fundamental mechanism of load transfer and its load-resistant for carbon fiber sheet reinforced concrete are not fully understood. In this study, three point bend test has been carried out to understand the damage progress and micro-failure mechanism of CFS reinforced concretes. For these purposes, four kinds of specimens are used, that is, concrete, respectively. Acoustic Emission(AE) technique was used to evaluate the characteristics of damage progress and failure mechanism of specimens. In addititon, two-dimensional AE source location was also performed to monitor crack initiation and propagation processes for four types of these specimens.

• Nuclear Engineering and Technology
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• v.30 no.1
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• pp.8-16
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• 1998

In this work a method to detect the vibrational peak and to decide the vibrational mode of detected peak for core internal vibration monitoring system which is particularly concerned on the core support barrel (CSB) and fuel assemblies is developed. Flow induced vibration and aging process in the reactor internals cause unsoundness of the internal structure. In order to monitor the vibrational status of core internal, signals from the ex-core neutron detectors are transformed into frequency domain. By analyzing transformed frequency domain signal, an analyst can acquire the information on the vibrational characteristics of the structures, i.e., vibration frequencies of each component, vibrational level, modes of vibration, and the causes of the abnormal vibration, if any. This study is focused on the development of the automated monitoring system. Several methods are surveyed to define the peaks in power spectrum and fuzzy theory is used to automatic detection of the vibrational peaks. Fuzzy algorithm is adopted to define the modes of vibration using the peak values from fuzzy peak recognition, phase spectrum, and coherence spectrum.

• Journal of the Korean Society for Nondestructive Testing
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• v.22 no.3
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• pp.239-245
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• 2002

Many civil and infrastructures continue to be used despite aging and the associated potential for damage accumulation. Therefore, the ability to monitor the health of these systems is becoming increasingly important. The purpose of this paper is to propose a real-time health monitoring system of cable-stayed bridge, based-on non-destructive measurement. And also this paper focuses on the safety assessment for bridge from health monitoring system to accomplish this safety assesment. Using the proposed health monitoring system, it helps bridge maintenance and reduces the economic cost of a life-cycle costs. Also it give important data to develop the design and analysis method for cable-stayed bridges.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.3
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• pp.1362-1376
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• 2016

A cloud computing system can be characterized by the provision of resources in the form of services to third parties on a leased, usage-based basis, as well as the private infrastructures maintained and utilized by individual organizations. To attain the desired reliability and energy efficiency in a cloud data center, trade-offs need to be carried out between system performance and power consumption. Resolving these conflicting goals is often the major challenge encountered in the design of optimization strategies for cloud data centers. The work presented in this paper is directed towards the development of an Energy-efficient and Performance-aware Cloud System equipped with strategies for dynamic switching of optimization approach. Moreover, a platform is also provided for the deployment of a Wind Farm CMS (Condition Monitoring System) which allows ubiquitous access. Due to the geographically-dispersed nature of wind farms, the CMS can take advantage of the cloud's highly scalable architecture in order to keep a reliable and efficient operation capable of handling multiple simultaneous users and huge amount of monitoring data. Using the proposed cloud architecture, a Wind Farm CMS is deployed in a virtual platform to monitor and evaluate the aging conditions of the turbine's major components in concurrent, yet isolated working environments.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.92-95
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• 2008

The Geostationary Ocean Color Imager (GOCI) is under development to provide a monitoring of ocean-color around the Korean Peninsula from geostationary platforms. It is planned to be loaded on Communication, Ocean, and Meteorological Satellite (COMS) of Korea. The GOCI has been designed to provide multi-spectral data to detect, monitor, quantify, and predict short term changes of coastal ocean environment for marine science research and application purpose. The target area of GOCI observation covers sea area around the Korean Peninsula. Based on the nonlinear radiometric model, the GOCI calibration method has been derived. The radiometric model of GOCI has been validated through radiometric ground test. From this ground test result, GOCI radiometric model has been changed from second order to third order. In this paper, the radiometric test performed to evaluate the radiometric nonlinearity is described and the GOCI radiometric error propagation is analyzed. The GOCI radiometric calibration is based on onboard calibration devices; solar diffuser, DAMD (Diffuser Aging Monitoring Device). The radiometric model error due to the dark current nonlinearity is considered as a systematic error. Also the offset correction error due to gain/offset instability is considered. The radiometric accuracy depends mainly on the ground characterization accuracies of solar diffuser and DAMD.

• Korean journal of communication and information
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• v.48
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• pp.306-325
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• 2009

This Study aims to thesis the purpose and educational methodology of media education for senior citizens. As background research, current situation and agendas regarding the media education for senior citizens were investigated. In further, quantative focal interview method was deployed to analyze recognition of teaches and education participants in media education for senior citizens. Focal interviews basis on the purpose, problems of education environment, preferred education method and suggestions of media education. The focal interview lead to in-depth opinion relying on experience of teachers and education participants. This study is expected to present the basis data for future theoretical systemization of neglected classes and for seeking educational utilization methods.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.1
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• pp.71-81
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• 2020

Enclosed pig house are creating an environment with high concentrations of gas and dust. Poor conditions in pig farms reduce pig weight and increase disease and accidents for livestock workers. In the pig house, the high concentration of harmful gas may cause asphyxiation accidents to workers and chronic respiratory disease by long-term exposure. As pig farm workers have been aging and feminized, the damage to the health of the harsh environment is getting serious, and real-time monitoring is needed to prevent the damage. However, most of the measuring devices related to humidity, harmful gas, and fine dust except temperature sensors are exposed to high concentrations of gas and dust inside pig house and are difficult to withstand for a long time. The purpose of this study is to develop an wearable based device to monitor the hazardous environment exposed to workers working in pig farms. Based on the field monitoring and previous researches, the measurement range and basic specifications of the equipment were selected, and wearable based device was designed in terms of utilization, economic efficiency, size and communication performance. Selected H₂S and NH₃ sensors showed the average error of 5.3% comparing to standard gas concentrations. The measured data can be used to manage the working environment according to the worker's location and to obtain basic data for work safety warning.

• Journal of Sensor Science and Technology
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• v.15 no.6
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• pp.417-424
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• 2006

An ubiquitous healthcare monitoring system for elderly person at home was designed for continuous healthy monitoring of elderly person or patients. Human vital signals, such as ECG and body temperature, were monitored by terminal PC or PDA via ECG and temperature sensor nodes on the patient's body. From the ECG data, the heart rate, tachycardia, bradycardia and arrhythmia were diagnosed on the terminal PC or PDA to assist doctor's or nurse's aid or patient itself to monitor the patient's condition and give medical examination. Artificial judgement support system was designed in server computer and the system support a doctor or nurser for management or treatment of the patient. This system can be applied to vital signal monitoring system for solitude elderly person at self house or home health care service part. And this ubiquitous healthcare system can reduce the medical expenses in coming aging or aged society.

• Journal of Digital Convergence
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• v.14 no.2
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• pp.141-148
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• 2016

Agricultural machines can be viewed as a very important factor to reduce the workforce and reduce production costs as well as keep up with now days trend caused Labor shortages and the workforce reduction by aging in rural. The latest agricultural machinery has developed into a major agricultural industry to apply and integrate the telecommunication, next-generation batteries, semiconductors, wireless communications, content and high-tech display industry technology with a wide range of applications. In this study, to apply the information and communication technologies on agricultural planters relied on a mechanical method, we designed a quick and sophisticated ICT convergence planters that enable to monitor.

• Journal of Family Resource Management and Policy Review
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• v.21 no.2
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• pp.1-24
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• 2017

The purpose of this study, which focuses on safe living as an important determinant of the quality of life for the elderly, is to provide policy proposals for their safe living in rural areas by examining their current living conditions and related policies. To examine the related policies, we analyzed government plans including: the first, second and third Basic Plan on Low Fertility and Aging Society, first implemented in 2006, the first, second and third Basic Plan for Healthy Families, also first implemented in 2006, and the first, second and third Five-year Plan for Improvement of the Quality of Life of Rural People and Regional Development of Rural Areas, first implemented in 2005. In addition to these plans, government projects concerning safe living environments were assessed. we present the following policy proposals for the safe living of the elderly in rural areas. First, integrated, customized policies are required for the rural elderly's everyday life. That is, elderly-friendly residential improvement policies are needed since accidents involving the rural elderly usually occur in their own houses. Policies should also be introduced to monitor and improve the elderly's nutritional and health status. Also considering the high proportion of elderly people in rural areas, policies must be aimed at creating elderly-friendly and family-friendly villages. Second, educational sessions for the elderly are necessary to raise their awareness of safety in everyday lives, which they often overlook.