• Corrosion Science and Technology
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• v.12 no.2
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• pp.85-92
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• 2013

This work is concerned with an evaluation of dynamic boric acid corrosion (BAC) of low alloy steel for reactor pressure vessel of a pressurized water reactor (PWR). Mockup test method was newly established to investigate dynamic BAC of the low alloy steel under various conditions simulating a primary water leakage incident. The average corrosion rate was measured from the weight loss of the low alloy steel specimen, and the maximum corrosion rate was obtained by the surface profilometry after the mockup test. The corrosion rates increased with the rise of the leakage rate of the primary water containing boric acid, and the presence of oxygen dissolved in the primary water also accelerated the corrosion. From the specimen surface analysis, it was found that typical flow-accelerated corrosion and jet-impingement occurred under two-phase fluid of water droplet and steam environment. The maximum corrosion rate was determined as 5.97 mm/year at the leakage rate of 20 cc/min of the primary water with a saturated content of oxygen within the range of experimental condition of this work.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.3
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• pp.167-173
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• 2003

Many of researches regarding mechanical properties of composite materials are associated with humid environment and temperature. Especially the temperature is a very important factor influencing the design of thermoplastic composites. However, the effect of temperature on impact behavior of reinforced composites have not yet been fully explored. An approach which predicts critical fracture toughness G$_{IC}$ was performed by the impact test in this work. The main goal of this work is to study the effect of temperature and span of specimen supports on the results of Charpy impact test for GF/PE composite. The critical fracture energy and failure mechanism of GF/PE composites were investigated in the temperature range of $60^{\circ}C;to;-50^{\circ}C$ by the Charpy impact test. The critical fracture energy showed the maximum at the ambient temperature, and it tended to decrease as the temperature increased or decreased from the ambient temperature. The major failure mechanisms are the fiber matrix debonding, the fiber pull-out and/or delamination and the matrix deformation.n.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.5
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• pp.713-718
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• 2016

Predicting precise specifications of differential mixed-signal circuits is a difficult problem, because analytically derived correlation between process variations and conventional specifications exhibits the limited prediction accuracy due to the phase unbalance, for most self-tests. This paper proposes an efficient prediction technique to provide accurate specifications of differential mixed-signal circuits in a system-on-chip (SoC) based on a nonlinear statistical nonlinear regression technique. A spectrally pure sinusoidal signal is applied to a differential DUT, and its output is fed into another differential DUT through a weighting circuitry in the loopback configuration. The weighting circuitry, which is employed from the previous work [3], efficiently produces different weights on the harmonics of the loopback responses, i.e., the signatures. The correlation models, which map the signatures to the conventional specifications, are built based on the statistical nonlinear regression technique, in order to predict accurate nonlinearities of individual DUTs. In production testing, once the efficient signatures are measured, and plugged into the obtained correlation models, the harmonic coefficients of DUTs are readily identified. This work provides a practical test solution to overcome the serious test issue of differential mixed-signal circuits; the low accuracy of analytically derived model is much lower by the errors from the unbalance. Hardware measurement results showed less than 1.0 dB of the prediction error, validating that this approach can be used as production test.

• Journal of muscle and joint health
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• v.26 no.3
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• pp.281-289
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• 2019

Purpose: This study aims to develop the Korean version of Presenteeism Scale for Students and verify its reliability and validity. Methods: This study conducted a survey with 320 undergraduate students who are attending nursing departments at three universities. The survey was conducted twice, from June 1 to August 31, 2017. Results: The Cronbach's α of K-PSS was .70 indicating high reliability. As a result of testing the content validity of K-PSS was verified by calculating the Item level-Content Validity Index (I-CVI) of .87. The correlation between Medical Outcome Study 36-item Short Form Health Survey (SF-36) score and Work Impairment Score (WIS), Work Output Score (WOS), Hours of absenteeism (HA) was analyzed to verify the concurrent validity of K-PSS. SF-36 score was correlated with WIS, WOS, HA. To test the differentiated validity of K-PSS, a total of 38 subjects were assessed by the paired t-test. As a result, only WIS score showed a significant difference between pre-test and post-test. Conclusion: Since the reliability and validity of the K-PSS developed through this study have been verified, it is expected to be used in various studies related to the presenteeism of students.

• Journal of Sensor Science and Technology
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• v.25 no.2
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• pp.155-159
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• 2016

In this work, we have developed a test system to examine whether the charge indicator of the plug-in hybrid electric vehicle (PHEV) works properly or not. In PHEV, the driver should charge the necessary electricity by plugging in manually and be able to know the charging status through the charge indicator conveniently located for the charging individual. Our system used the CAN bus to transmit the same commands from ECU to the indicator to test the proper operation of the indicator lights. It measured the electric current values during operation and analyzed to determine the quality of the indicators. The inspection items included the proper packaging, the electrical shorts, the LED lighting during charging, the LED lighting for charging failure, and the LED lighting when errors occur. We developed the system for the operators in the factory allowing them to approve the test results at the site. We developed the hardware, the control software, and the software to store the test results and the history of the products in the database. Serial numbers were given to the good quality products and the bar code labels were printed to trace the products afterwards. Through this work, we developed a system to inspect the electric parts in real time upon fabrication. We are planning to further improve our system to inspect the brightness of the indicator by adding the vision inspection in future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.462-470
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• 2018

This descriptive survey was conducted to explore the effects of work engagement and its associated factors among general hospital nurses. Nurses working in general hospitals were recruited in D city and K region. Data were analyzed by descriptive statistics, t-test, one-way ANOVA, Pearson's correlations, and stepwise multiple regression using IBM SPSS 25. The mean score of work engagement of the subjects was 3.08. The mean scores of emotional modulation effects in profession, patient focused emotional suppression, and emotional pretense by norms which are subgroups of emotional labor by norms were 3.82, 3.28, and 3.22, respectively, while that of the nursing work environment was 2.59. Work engagement was significantly positively correlated with emotional modulation effects in profession (r=0.30, p=0.001), patient-focused emotional suppression (r=0.20, p=0.030), and nursing work environment (r=0.21, p=0.024). The results showed that the factors that affect the work engagement were age, current position, and emotional modulation effects in profession, which explained 20% of the variance in work engagement (F=10.37, p<0.001). Therefore, to establish strategies for improving the level of work engagement, it is necessary to consider age and current positions of nurses and to develop a nursing intervention program to strengthen emotional modulation effects among general hospital nurses.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.371-376
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• 2003

The objective of this paper is to compare the site-to-site variability of ISO 10844 pass-by-noise test sites. In order to investigate the site-to-site variance of test surfaces, European commercial tires are tested at seven different test sites. Three Korea test sites and four Europe test sites are selected.. The pass by noise test is executed according to a 2001/43/EC regulation. A]though the ISO surface has a very specific track composition, it does not reduce the variation of pass-by-noise measurements over the surface of test sites. This paper shows that the test results of pass-by-noise level are different depending on the test sites. The correlation obtained in this work is able to predict the pass by noise level for certain test site using the data measured from another test site. 17he prediction value is range with an error within 1dB(A).

• Journal of the Korea Society of Computer and Information
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• v.19 no.6
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• pp.119-128
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• 2014

In this study, the social welfare field training course there is a growing awareness as professionals in order to verify the impact was conducted. G-local four-year university study social work majors by sampling 198 people were examined for the purpose, through self - survey was conducted. Materials and analytical methods in order to identify the characteristics of a variable frequency, and technical analysis, T-test, F-test, ANOVA, correlation (correlation), Regression (regression) was used for the SPSS 14.0. The results are as follows. First, the personal factors of the individual physician trainees reflect (${\beta}=.197$), and then the same about Social Welfare satisfaction (${\beta}=.205$) of the Social Welfare majors had significant impact on career identity. Second, the personal factors they chose what to major in social work satisfaction (${\beta}=-.291$), and if you feel you select a parent with a major in Social Work and Social Welfare major students feel the satisfaction of having a significant effect on the level of career decision crazy. Third, individual reflect personal physician factors (${\beta}=.156$) is significantly influenced the behavior of career preparation.

• Journal of Korean Academy of Nursing
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• v.45 no.6
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• pp.879-889
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• 2015

Purpose: The purpose of this study was to construct and test a structural equation model of quality of work life for clinical nurses based on Peterson and Wilson's Culture-Work-Health model (CWHM). Methods: A structured questionnaire was completed by 523 clinical nurses to analyze the relationships between concepts of CWHM-organizational culture, social support, employee health, organizational health, and quality of work life. Among these conceptual variables of CWHM, employee health was measured by perceived health status, and organizational health was measured by presenteeism. SPSS21.0 and AMOS 21.0 programs were used to analyze the efficiency of the hypothesized model and calculate the direct and indirect effects of factors affecting quality of work life among clinical nurses. Results: The goodness-of-fit statistics of the final modified hypothetical model are as follows: ${\chi}^2=586.03$, ${\chi}^2/df=4.19$, GFI=.89, AGFI=.85, CFI=.91, TLI=.90, NFI=.89, and RMSEA=.08. The results revealed that organizational culture, social support, organizational health, and employee health accounted for 69% of clinical nurses' quality of work life. Conclusion: The major findings of this study indicate that it is essential to create a positive organizational culture and provide adequate organizational support to maintain a balance between the health of clinical nurses and the organization. Further repeated and expanded studies are needed to explore the multidimensional aspects of clinical nurses' quality of work life in Korea, including various factors, such as work environment, work stress, and burnout.

• Journal of the Korean Society of Food Culture
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• v.21 no.6
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• pp.702-713
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• 2006

The purpose of this study was to identify the influence of school foodservice dietitians' work value on job satisfaction, organizational commitment, and turnover intentions. Also, this study explored the role of the expectation to the institution of nutrition teachers as a moderating variable in three relationships: 1) between work value and job satisfaction, 2) between work value and organizational commitment, and 3) between work value and turnover intentions. This study surveyed dietitians who worked at school foodservice in Kyunggii and Daegu${\cdot}$Gyeoungbuk province. A total of 509 responses were collected using on-site survey and online survey (response rate 59.3%). This study conducted hierarchical regression analysis to test the moderating effect of the expectation to the institution of nutrition teachers. Results of hierarchical regression showed that work value of status upgrade had a positive effect on job satisfaction to promotion opportunity and salary, and such effect was more significantly apparent in high expectation to new work. In addition, work value of status upgrade had a positive effect on turnover intention, and such effect was more significantly apparent in low expectation to new work environment improvement. Work value of work activity preference also appeared to have a positive effect on organizational commitment, and such effect was more significantly apparent in high expectation to social status and professionalism.