• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1993.04a
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• pp.23-29
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• 1993

내부공진 (.omega.$_{3}$ = .omega.$_{1}$ + 2.omega.$_{2}$)을 가진 원판 의 조합공진(.OMEGA. = 2.omega.$_{1}$ + .omega.$_{2}$)응답의 안정성 을 해석한 결과 다음과 같은 결론을 얻었다. 1) 모든 진폭이 0(.alpha.$_{1}$=.alpha.$_{2}$=.alpha.$_{3}$=0)인 공진응답 은 매개변수의 값에 관계없이 안정하다. 2) 모든 진폭이 0이 아닌 (.alpha.$_{1}$.neq.0, .alpha.$_{2}$.neq.0, .alpha.$_{3}$.neq.0) 공진응답은 쌍으로 존재하는데 진폭이 큰 응답(upper branch)은 안정하나 진폭이 작은 응답(lower branch)은 불안정하다. 3) 진폭이 0이 아닌 공진응답이 존재하지 않는 경우에는 선형계와 마찬가지 로 모든 진폭이 0이 공진응답(결과적으로 비공진 응답)이 계의 응답을 지배 하지만 모든 진폭이 0이 아닌 공진응답이 존재하는 경우에는 안정한 공진응 답이 2개이므로 초기조건이 실제의 응답을 결정하게 된다.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.6
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• pp.166-175
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• 1999

This paper describes a design and performance evaluation of robust controller which overrides unstable motion and pulls out quickly after water entry of underwater vehicle dropped from aircraft or surface ship. We use 6-DOF equation for model of motions and assume parameter uncertainty to reflect the difference of real motion from modelled motion equation. we represent a nonlinear system with uncertainty as Takagi and Sugeno's(T-S) fuzzy models and design controller stabilizing them. The fuzzy controller utilizes the concept of so-called parallel distributed compensation (PDC). Finally, we confirm stability and performance of the controller through computer simulation and hardware in the loop simulation (HILS).

• The Journal of the Korea Contents Association
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• v.11 no.12
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• pp.190-205
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• 2011

The purpose of this study was to investigate the effects of the MICE industrial employee's job stressors on intent to leave and test of the mediating role of job satisfaction and job commitment. For the study, job stressors were defined 3 groups with 7 sub-factors, such as role stressors of role ambiguity, role conflict and role overload, task stressors of job routineness and job heteronomy, organizational stressors of job insecurity and distributive injustice. Data were collected from 303 MICE industrial employees in metropolitan area by structured questionnaires. Collected data were analyzed by AMOS 18.0 and findings are as follows. Firstly, on aspect of total effectiveness, the seven job stressors had harmful effect on intent to leave, especially organizational stressors had more serious effect on intent to leave than role stressors. Secondly, not only job satisfaction and job commitment had meditators role but also influenced on intent to leave directly. Thirdly, role ambiguity had effect on intent to leave indirectly through the job satisfaction, while role conflict and role overload had effect on intent to leave directly, and also indirect effectiveness on it through the job commitment. Fourthly, job routineness and job heteronomy had effected on intent to leave only through the meditators. Not only job insecurity and distributive injustice had influenced on intent to leave directly but also effectiveness on it indirectly through the meditators.

• Journal of the Korean GEO-environmental Society
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• v.19 no.1
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• pp.15-23
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• 2018

In this study we performed risk evaluation based on parameters using the SINMAP, GIS-based extended program in order to predict ground disaster that is frequent recently. As for the risk evaluation, in order to understand the effects of parameters, we defined that the ranges of internal friction angles and T/R values as important variables had three and four patterns, respectively. The results of the interpretation were compared with those of the existing landslide in order to identify landslide flow and to evaluate the applicability of the parameters. The analysis of the geomorphologic saturated zone showed that the boundary saturated zone and the saturated zone were almost consistent with the site of avalanche of earth and rocks and the area of underground water convergence was correlated to the area where collapse started, indicating that the geomorphologic saturated zone may serve as an index for estimating possibility of landslide when used with slope distribution, colluvial soil, and structures inducing landslide in combination. When the lower limit of the internal friction angle increased more, the upper threshold decreased by 50 to 70% and the influence on the stability index was higher, but the influence was declined within the range of lower wetness index. The analysis of changes based on wetness index range showed that all the groups have similar SI distribution, except for the one in which mean altitude values are applied, indicating that the results are susceptible more by the internal friction angle than by the wetness index.

• Journal of Industrial Convergence
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• v.21 no.4
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• pp.41-63
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• 2023

Organizational members' innovative behavior is a key element that promotes organizational growth and sustainability. With today's unstable environment of economic and market , the importance of employees' innovative behavior is being emphasized. The reason is that employees' innovative behaviors play an important role in securing a organizational competitiveness. Based on this, this study focused on ways to improve employees' innovation behavior. Specifically, the causal relationship between participatory leadership and employees' innovative behavior was identified and the influence of innovative behavior was also verified. Furthermore, in the process of participatory leadership influencing employees' innovative behavior, the serial multiple mediating effect of knowledge sharing and creativity was verified. In order to demonstrate the hyphotheses, this study focused on 237 employees who work in Chinese SMEs. The results of the empirical analysis showed that participatory leadership had a positive effect on knowledge sharing, creativity, and innovative behavior. In addition, the serial multiple mediating effects of knowledge sharing and creativity on the relationship between participatory leadership and innovative behavior was significant. Overall, this study verified the positive role of participatory leadership that enhances employees' innovative behavior in Chinese SMEs and contributed to expanding the research field related to employees' innovative behavior through serial multiple mediating model.

• Journal of Digital Convergence
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• v.15 no.9
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• pp.519-532
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• 2017

The purpose of this study was to investigate the content of job stress experienced by call center consultants. For that purpose, the investigator interviewed 11 call center consultants one-on-one in D City, conducting qualitative analysis of content of job stress they experienced according to Giorgi's phenomenological analysis procedure. As a result, there were classifications of job characteristics and individual characteristics. They were further classified into 8 categories and 24 subcategories. As for job characteristics, there were "limitations of work performance," "work burden," "inflexible work style," "uncontrolled customers," and "controlled demand." As for individual characteristics, there were "psychological instability," "personality vulnerabilities," and "poor coping resources." The categories of job characteristics and personal characteristics were classified into limit and control levels, respectively. It is found that poor coping resources mediate between job stress and personal characteristics. Based on these results, we discussed not only the existing organizational responses but also the combined interventions that mitigate the psychological stress after the unstable psychological state of the individual.

• Journal of Korea Water Resources Association
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• v.45 no.7
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• pp.643-656
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• 2012

There has been an increase for the landslide areas and restoration expenses due, in large part, to the increased locally heavy rains caused by recent climate change as well as the reckless development. This study carried out a slope stability analysis by the application of distributed wetness index, using the GIS-based infinite slope stability model, which took the root cohesion effect into consideration, for part of Mt. Umyeon in Seoul, where landslide occurred in July 2011, in order to compensate the defects of existing analysis method, and subsequently compared its result with the case on the exploitation of lumped wetness index. In addition, this study estimated the distributed wetness index by methodology, applying three methods of specific catchment area calculation: single flow direction (SFD), multiple flow direction (MFD), and infinity flow direction (IFD), for catchment area, one of the variables of distributed wetness indices, and finally implemented a series of comparative analysis for slope stability by methodology. The simulation results showed that most unstable areas within the study site were dominantly located in cutting-area surroundings along with the residential area and the mountaintop and unstable areas of IFD and lumped wetness index method were similar while SFD and MFD provided smaller unstable areas than the two former methods.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.8
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• pp.474-481
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• 2018

The purpose of this study was to examine the mediating effects of maternal family experience on the relationship between mothers' tendency to addicted to smartphones and the social competence of young children. The subjects of this study were 481 mothers who delivered infants to a kindergarten or daycare center in Jeju area After conducting the questionnaire, the results of the responses were analyzed. To analyze the collected data, structural equations were implemented using SPSS Statistic 18.0 program. The results of this study are summarized as follows. First, the correlational analysis showed that the tendency of the addiction of smartphone and the social ability of the infant showed a significant correlation with the mother's family experience. Second, in the relationship between the mother's smartphone tendency and the social competence of the infant, The research model and the competition model were set up to examine the mediating effect and the competition model was found to be more appropriate. As a result, it can be seen that mother's original family experience is partly mediated in relation to mother's tendency to add to smartphone and social competence of infant. Based on these results, the implications of this study and suggestions for subsequent research were discussed.

• Journal of Industrial Convergence
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• v.18 no.2
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• pp.59-67
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• 2020

This study aims to contribute to overcoming difficulties that disability assistance workers experience by verifying the effect of job stress and self-efficacy on their turnover intentions, and whether job engagement has a mediating effect in the process. For this purpose, a survey was performed on 290 disability assistance workers associated with disability support organizations in the Seoul and Gyeonggi area during the period of 2019.5.1.-2019.6.30. The collected survey data was analyzed with the SPSS 24.0 statistical software, the results of which are as follows. First, job stress and self-efficacy appears to affect job engagement. High levels of conflict and maladjustment in the workplace had adverse effects on job engagement, while high levels of emotional, evaluative, and informational support had positive effects. Second, job stress and self-efficacy also had an effect on turnover intentions. High levels of conflict, instability, and maladjustment in the workplace led to a higher level of turnover intentions. Third, job engagement had a mediating effect between job stress and turnover intentions. Fourth, job engagement had no mediating effect between self-efficacy and turnover intentions. These results serve to propose practical measures to reduce the job stress and improve the job engagement of disability assistance workers.

• Journal of the Korea Convergence Society
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• v.7 no.6
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• pp.67-74
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• 2016

The study, was conducted to become conscious of the impact of emotional labour on dental hygienists' self-esteem with job stress. Participants were 205 dental hygienist's in the dental clinic. Data were gathered from Jan 3 to Jan 30, 2016, using structured questionnaires. The analysis shows that there was a negative correlation with self-esteem in emotional labour, however, positive correlation was presented in employment stress. It also appears to have no relationship between self-esteem and job stress. Therefore, emotional labour has a direct effect on increasing job stress and lowers self-esteem. The lowered self-esteem simultaneously has an indirect effect on increasing job stress. The measures to counter the problems of emotional labour of dental hygienist and education considering dental hygenist's self-esteem should be accomplished place to maintain the level of emotional labour and the clinic's determination to rectify the issues are essential.