• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.12
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• pp.3030-3037
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• 2013

Life time of facilities is different In case of operating environment and frequency of use. So, the durable year of the facilities is only considered to replace the facilities at present. Thus, system management is needed economical assesment based on condition evaluation through performance analysis of facilities. This research makes a proposal for scientific condition evaluation table through physical assessment, performance analysis assessment, durable years assessment about satellite communication facilities being used in K-water. Consequentially, reasonable replacement plan is established for satellite communication facilities.

• Journal of the Korean Society of Safety
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• v.33 no.2
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• pp.152-157
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• 2018

The degradation and damage of the components for ballasted track could be caused a serious problem for railway safety. Therefore, the integrity evaluation of ballasted track condition is important to ensure and predict that the track safety and track maintenance. Various track components such as rail pad, ballast, sleeper, and rail that are widely used in Republic of Korea and represent a range of physical properties have been selected for this research. In this study, the experimental modal analysis was performed by the non-destructive testing. Modal test results were obtained from the field test and used to assess the condition of the track components. From the field test, the system of ballasted track was found to be simplified as a two-degree-of-freedom(2DOF) dynamic system. The condition of track component was found to directly affect the dynamic response of ballasted tracks. As the results, the dynamic properties of the track component was depend on the track condition and was distributed more roughly and over a wider range than its initial design values. Further, the methodology presented in this study is possible to determine experimentally the fundamental track parameters which are required in the numerical analysis, and also are useful for the safety assessment of track condition.

• The Research Journal of the Costume Culture
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• v.14 no.1
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• pp.93-107
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• 2006

This study was designed from the concept that there is a need to establish the uniform for new emerging jobs in modern society. The purpose of the study was to examine dental hygienists'wearing condition, satisfaction, and design evaluation as to provide information for the development of dental hygienists' uniform. Three hundred fifteen dental hygienists completed questionnaires, and data were analyzed by descriptive statistics, factor analysis, multiple regression, ANOVA, and Duncan's test. The findings from the study were following. First, majority of dental hygienists currently wear shirts and pants two-piece uniform in white with no print. Second, dental hygienists' overall satisfaction level for their uniform was medium, and symbolic satisfaction as well as functional satisfaction did not reach the medium level while aesthetic satisfaction was above medium. The satisfaction levels were significant different between groups according to the education, clinic size, and work experience. Third, aesthetic satisfaction levels influenced on the job image as professional. Finally, designs consisting of two-piece style with shirts and pants and having Peter pan collar were recorded high evaluation. The findings can be implemented into dental hygienists' uniform design.

• International Journal of Automotive Technology
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• v.6 no.4
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• pp.367-374
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• 2005

This paper proposes a sound quality index to evaluate the vehicle interior noise. The index was developed using a correlation analysis of an objective measurement and a subjective evaluation data. First, the objective set of measurements was obtained at two specified driving conditions. One is from a wide-open test condition and the other is from a constant-speed test condition. At the same time, subjective evaluation was carried out using a score of ten scale where 17 test engineers participated in the experiment. The correlation analysis between the psycho-acoustic parameters derived from the objective measurement and the subjective evaluation was performed. The most critical factors at both test conditions were determined, and the corresponding equations for the sound quality were obtained from the multiple factor regression method. Finally, a comparative work between previous index and present index was performed to validate the effectiveness of the proposed index.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.2
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• pp.1-7
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• 2012

A Failure data from operating condition includes various failures. Reliability evaluation by operating condition is more correct than test condition. Additional, the evaluation result by operating condition is widely used for quality assurance, forecasting amount of manufacturing at EOL. To discover valuable things from the failure data, arrangement of the failure data and information technique to handle data is needed among many failure data. This paper introduces a reliability prediction program to solve this problem based on the failure. And new technologies for parameters estimation with method of Graphic-Wizard-Parameters-Estimation and Genetic Algorithm are introduced.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.27 no.4
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• pp.157-164
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• 2004

Trouble prevention of facilities in operation process plays an important role for improving facilities productivity as production systemization is installed with development of facilities automatization. Condition monitoring predicts machine's internal changes by periodically recording vibration occurred in the machine. This article considers a method of establishing statistical criteria for facilities troubles by utilizing machine condition evaluation and operation limit standards of ISO 10816-3.

• International Journal of Concrete Structures and Materials
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• v.9 no.4
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• pp.427-438
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• 2015

The present work proposes a new image analysis method for the evaluation of the multi-walled carbon nanotube (MWNT) distribution in a cement matrix. In this method, white cement was used instead of ordinary Portland cement with MWNT in an effort to differentiate MWNT from the cement matrix. In addition, MWNT-embedded cement composites were fabricated under different flows of fresh composite mixtures, incorporating a constant MWNT content (0.6 wt%) to verify correlation between the MWNT distribution and flow. The image analysis demonstrated that the MWNT distribution was significantly enhanced in the composites fabricated under a low flow condition, and DC conductivity results revealed the dramatic increase in the conductivity of the composites fabricated under the same condition, which supported the image analysis results. The composites were also prepared under the low flow condition (114 mm < flow < 126 mm), incorporating various MWNT contents. The image analysis of the composites revealed an increase in the planar occupation ratio of MWNT, and DC conductivity results exhibited dramatic increase in the conductivity (percolation phenomena) as the MWNT content increased. The image analysis and DC conductivity results indicated that fabrication of the composites under the low flow condition was an effective way to enhance the MWNT distribution.

• Journal of the Ergonomics Society of Korea
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• v.29 no.1
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• pp.121-128
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• 2010

The purpose of this study is to confirm the impact of noise on subject accomplishment as well as physical/mental load, and evaluates the effects of noise-masking and earplug. 15 college students participate in the test, and the comparison is performed by executing four projects according to conditional categories of noise environments; control condition, noise condition, earplug condition, and noise-masking condition. Noise in the field site of the H manufacturer was used as the noise source, the general job aptitude test which consist of linguistic ability, math ability, perception ability, reasoning ability was used as the task of this project. To estimate physical/mental load evaluation, we used the heart rate R-R interval, Criteria flicker fusion frequency(CFF) and measured NASA-TLX workload for subjective evaluation. As the research outcome, it is shown that there is a meaningful difference for the project task score, dropping rate of CFF, the heart rate, and NASA-TLX subjective evaluation score according to conditions of noise environment. Therefore, the impact of noise on capability of subject accomplishment as well as physical/mental load was confirmed along with the effects of using earplug and noise-masking.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.06a
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• pp.382-387
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• 2005

An electrochemical evaluation on the corrosion resistance for heavy anticorrosive paint was carried out for 5 kinds of heavy anticorrosive paints such as High solid epoxy(HE), Solvent epoxy(SE), Tar epoxy(TE), Phenol epoxy(PE), and Ceramic epoxy(CE) as parameters of DFT(Dry Film Thickness, 25${\mu}m$50${\mu}m$, solution condition(Flow of Nonflow). Corrosion current density of HE(DFT 50${\mu}m$ in case of flow condition was larger than that of nonflow condition. However, their values of the other anticorrosive paints were decreased compared to the nonflow condition. The values of AC impedance were increased with increasing of DFT regardless of kinds of anticorrosive paints. And the polarization resistance of cyclic voltammogram showed a good tendency to correspond with well the values of AC impedance measurement. HE and CE had a relatively good corrosion resistance than other heavy anticorrosive paint.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.6
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• pp.45-58
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• 2005

The objective of this study is to the integrated evaluation of the present condition and satisfaction of visitors of rooftop greening area using quantitative and qualitative method. The thirteen green roofs were selected to investigate environmental variables as like building structure, soil, water, atmosphere and climate environment and questionnaire survey for investigate the satisfaction of visitors was conducted. The results of this study are as follows : remove of the hazardous inflow of species, install rain water recycling facility, install outdoor unit of air condition where not to affect plants in green roof, install safety facilities in the case of making resting place, plant variable vegetation and so on. The result of questionnaire survey are that visitors want to make more comfortable resting space. The more bigger the resting space and privacy, the more satisfaction of visitor became high. In conclusion, green roofs implementation should be considered reduction of temperature and delay of runoff, insulation effect and ecological restoration as well as rooftop greening is focused on the development of resting space nowadays.