• Journal of the Korean Solar Energy Society
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• v.27 no.4
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• pp.97-103
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• 2007

This study was carried out to compare the thermal performance and operating characteristics of evacuated tubular solar collector(ETSC) with different working fluid. The evacuated tubular solar collectors with different working fluid of heat pipe were investigated in the same operating condition for a indoor experiment equipment. First, the result of working fluid with Water showed that $F_R({\tau}{\alpha})$ was 0.6636 and $F_RU_L$ was -1.8457 Second, Ethanol showed that $F_R({\tau}{\alpha})$ was 0.6147 and $F_RU_L$ was -0.6365. Third, Flutec-pp9 showed that $F_R({\tau}{\alpha})$ was 0.515 and $F_RU_L$ was -3.2313. Finally MA's showed that $F_R({\tau}{\alpha})$ was 0.6572 and $F_RU_L$ was -2.0086.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.70-75
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• 2007

This study was carried out to compare the thermal performance and operating characteristics of evacuated tubular solar collector(ETSC) with different working fluid. The evacuated tubular solar collectors with different working fluid of heat pipe were investigated in the same operating condition for a indoor experiment equipment. First, the result of working fluid with Water showed that $F_R({\tau}{\alpha})$ was 0.6636 and $F_{R}U_{L}$ was -1.8457. Second, Ethanol showed that $F_R({\tau}{\alpha})$ was 0.6147 and $F_{R}U_{L}$ was -0.6365. Third, Flutec-pp9 showed that $F_R({\tau}{\alpha})$ was 0.515 and $F_{R}U_{L}$ was -3.2313. Finally MA's showed that $F_R({\tau}{\alpha})$ was 0.6572 and $F_{R}U_{L}$ was -2.0086.

• Transactions of the Korean hydrogen and new energy society
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• v.29 no.5
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• pp.483-489
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• 2018

Recently proposed organic flash cycle (OFC) was shown to potentially improve power generation using low grade heat source. In this paper, a thermodynamic performance is carried out for a modified OFC employed double expansions. Effects of the selection of working fluid and the important system parameters such as the temperatures in flash evaporators on the system performance were extensively investigated. Results showed that the system performances are strongly influenced with the system parameters and selection of the working fluid, and the power generation can be increased compared to the basic OFC.

• The Journal of Korean Physical Therapy
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• v.34 no.6
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• pp.304-311
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• 2022

Purpose: The purpose of this study was to investigate the knowledge, awareness and performance of COVID-19 infection control among physical therapists and to identify the impact factors on performance Methods: Data were collected from March 16th to March 24th in 2022 from the physical therapist's in Busan. Data analysis was conducted on 170 surveys, after excluding 27 surveys that were found to be unsuitable for data analysis. Results: When correlating the study variables, knowledge and awareness were found to have a positive, meaningful correlation with performance. Performance of COVID-19 personal infection control regression analysis showed that the working department (clinic and long-term care hospital), clinical experience, the more knowledgeable, the awareness (personal), and the more clinical experience had significant positive impacts on the performance of COVID-19 infection control. Performance of COVID-19 treatment room infection control regression analysis showed that the working department (long-term care hospital), educational experience, the awareness (treatment room) had significant positive impacts on the performance of COVID-19 infection control Conclusion: The results of this study may be used as basic data for educating physical therapist's working at the COVID-19 response department. This study suggests that physical therapist's need educational programs to improve their knowledge and awareness and performance of infection control against infectious diseases such as COVID-19. Differentiated physical therapists practice education curricula must be developed and provided after understanding the varying characteristic of physical therapist's with different levels of work experience.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.9
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• pp.2314-2333
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• 2023

It is significant to predict the performance degradation of complex electromechanical systems. Among the existing performance degradation prediction models, belief rule base (BRB) is a model that deal with quantitative data and qualitative information with uncertainty. However, when analyzing dynamic systems where observable indicators change frequently over time and working conditions, the traditional belief rule base (BRB) can not adapt to frequent changes in working conditions, such as the prediction of aeroengine performance degradation considering working condition. For the sake of settling this problem, this paper puts forward a new hidden belief rule base (HBRB) prediction method, in which the performance of aeroengines is regarded as hidden behavior, and operating conditions are used as observable indicators of the HBRB model to describe the hidden behavior to solve the problem of performance degradation prediction under different times and operating conditions. The performance degradation prediction case study of turbofan aeroengine simulation experiments proves the advantages of HBRB model, and the results testify the effectiveness and practicability of this method. Furthermore, it is compared with other advanced forecasting methods. The results testify this model can generate better predictions in aspects of accuracy and interpretability.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.10
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• pp.1571-1583
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• 2008

The study aimed to investigate the actual condition of working clothes in the Changwon National Industrial Complex and to analyze the industrial workers' satisfaction with and preference to the working clothes in terms of the clothing performance and work motion factors. 1 major companies in machinery, automotive, industrial engineering, shipbuilding and rolling stock industries located in the industrial complex were selected as the subject firms. Approximately 900 workers responded to the questionnaire designed for the research and the results derived from the research were as follows. (1) The subject employees were divided into 4 work groups, i.e. the $1^{st}$ work group: managerial, general affairs, sales, production planning; the $2^{nd}$ group: quality assurance, material planning and distribution, product inspection; the $3^{rd}$ group: electric, facilities, machinery, vehicles; and the $4^{th}$ group: cutting, pressing, rolling, welding and coating. (2) The significant work environmental factors considered by all work groups were air ventilation, noise and dust factors and in particular, the most dissatisfied factors evaluated by manufacture workers were insulation, noise, dust and vibration. (3) According to the employees' work motion evaluation, the work motion diversity and frequency increased in proportion to the degree of work intensity. Besides, manufacture workers more frequently wore the working clothes even during the off-duty hours comparing to the evaluation of the other work groups. (4) The most important clothing performance factors considered by manufacture work groups were perspiration absorption, stretch, air permeability, tactile sense softness, soil proof in order.

• Human Ecology Research
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• v.61 no.4
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• pp.521-541
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• 2023

The purpose of this study is to demonstrate the antecedent and consequential factors of satisfaction with the flexible working system. Organizational culture was examined as an antecedent factor, while job satisfaction, work performance, organizational commitment, turnover intention, and quality of life were examined as outcome factors. The data of 2,785 public officials who used the flexible work system in the Korea Institute of Public Administration (2022) data set were analyzed using SPSS 28.0. and PROCESS macro's Model 4. The main research findings are as follows. First, organizational cultures that respect individuality and cooperation, supports management, and aims for work autonomy all positively and significantly affect satisfaction with the flexible working system. When ranking the size of influence by the type of organizational culture, work autonomy, respect for individuality, and a cooperative organizational culture had a positive impact in that order, with work autonomy being the most influential factor. In addition, the public officials' age, job preparation period, self-evaluation of workload, and overtime working hours are significant antecedents of satisfaction with the flexible work system. Second, when examining consequential factors, a high level of satisfaction with the flexible working system affects job satisfaction (+), work performance (+), organizational commitment (+), turnover intention (-), and quality of life (+). Job satisfaction was an especially valid mediator between satisfaction with the flexible working system and other consequential factors, including work performance, organizational commitment, turnover intention, and quality of life.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.2
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• pp.223-231
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• 2011

The thermal efficiency of energy-to-power conversion becomes uneconomically low when the temperature of heat source drops below $370^{\circ}C$. ORC (Organic Rankine Cycle) has attracted much attention in last few years due to its potential in reducing consumption of fossil fuels and relaxing environmental problems, and its favorable characteristics to exploit low-temperature heat sources. In this work thermodynamic performance of ORC using nine working fluids is comparatively assessed. Special attention is paid to the effect of system parameters such as turbine inlet temperature and pressure on the characteristics of the system such as volumetric flow rate and quality at turbine exit, latent heat, net work as well as thermal efficiency. Results show that in selection of working fluid it is required to consider various criteria of performance characteristics as well as the thermal efficiency. Results also show that the system efficiencies become same irrespective of kind of working fluid when the temperature of heat source decreases to low range.

• Smart Structures and Systems
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• v.26 no.1
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• pp.11-21
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• 2020

The hinge joint is the key to the overall cooperative working performance of the assembled beam bridge, and it is also the weakest part during the service period. This paper proposes a method for monitoring and evaluating the lateral cooperative working performance of fabricated beam bridges based on dynamic strain correlation coefficient indicator. This method is suitable for monitoring and evaluation of hinge joints status between prefabricated girders and overall cooperative working performance of bridge, without interruption of traffic and easy implementation. The remote cloud monitoring and diagnosis system was designed and implemented on a real assembled beam bridge. The algorithms of data preprocessing, online indicator extraction and status diagnosis were given, and the corresponding software platform and scientific computing environment for cloud operation were developed. Through the analysis of real bridge monitoring data, the effectiveness and accuracy of the method are proved and it can be used in the health monitoring system of such bridges.

• Science of Emotion and Sensibility
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• v.4 no.2
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• pp.63-68
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• 2001

We purpose to evaluate the fatigue of the error correcting task on monitoring with color temperature 2700 K, 4000 K and 6500 K. Results of questionnaire on subjective feeling of visual fatigue, mental fatigue and concentration. Visual fatigue and mental fatigue level were the lowest, concentration level was the highest and working performance was the best at 2700 K. At 6500 K, mental fatigue level was the highest and concentration level is the lowest. At 4000 K, visual fatigue level was the highest and working performance shown the worst ratio of correcting answers. As results, color temperature 2700 K is the best condition of color temperature to perform the error correcting task on monitoring.