• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.105-108
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• 1993

This paper is concerned with a two-degree-offreedom control system design for a flexible arm, a two-degree-of-frecdom control system can achieve a robust stability specification and a control performance specification independently. By this property we improve the control performance with maintaining the same robust stability level as that of the onc-dcgree-of-freedom control system. At First we design a two-degree-of-fteedom control system which includes a feedforward controller and a feedback controller. The feedforward controller can be given by specifying a transfer function of a dcsired closed-loop model. We obtain a feedback controller by solving a mixed sensitivity problem. Several numerical results show that two-degree-of-freedom control systems acheive a better control performance than that of one-degree-of-freedom control systems.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.6
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• pp.927-934
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• 2017

This paper is concerned with applicability of two-degree-of-freedom controllers to the recently suggested i-PID controllers, in which unknown parts of the plant are taken into account without any modeling procedure. First, i-PID controller with two-degree-of-freedom is applied to a specific model, called Anisochronic model, to confirm the usefulness of this method. Second, using the original examples of i-PID controllers, it is confirmed that performance/robustness of system are to be improved due to two-degree-of-freedom, especially when the input changes suddenly. It is seen that as the desired robustness increases the optimal value of two-degree-of-freedom parameter ${\alpha}_A$ would be negative. It is checked and verified that if this value was limited to 1 or less as is generally known, performance would be degraded.

• Women's Health Nursing
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• v.5 no.1
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• pp.96-110
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• 1999

This study examined the correlation between of self-confidence and satisfaction in maternal role performance among primiparas. The subjects were 144 mothers, who were recruited from four general hospitals in Pusan. The data were collected from May 1. to August 31 in 1997. Self-confidence in ability to cope with tasks of motherhood and mother's satisfaction with motherhood and infant care were measured by the scales developed Lederman and associated(1981). Percentage, t-test, ANOVA, and Pearson Correlation Coefficient were obtained by using SPSS program. The results of the study were summarized as follows, 1. The degree of self-confidence in maternal role performance was above average with a mean score of 2.60. 2. The degree of satisfaction in the maternal role performance was above average with a mean score of 3.20. 3. There were positive correlations between the degree of self-confidence and the degree of satisfaction in the maternal role performance(r=.3035, p<.001). In conclusion, since self-confidence in maternal role performance is positively related to maternal satisfaction in the role performance, nursing intervention to improve maternal role performance may lead mother's increased maternal self-confidence and satisfaction in maternal role performance. Futher research is needed to prove the causality.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.1
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• pp.9-16
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• 1997

The method of designing robust two degree of freedom(2 DOF) controllers for linear systems with parameter uncertainties and unmodeled dynamics is presented in this paper. Robust performance condition that accounts for robust model matching of closed loop system and disturbance rejection is derived. Using the robust performance condition, the feedback controller is designed to meet robust stability and disturbance rejection specifications, while prefilter is used to improve the robust model matching properties. The $H^{\infty}$ and $\mu$ controller for six degree of freedom vehicle with parameter variations are designed and compared. Simulations for hydrodynamic parameter variations and disturbance are presented to demonstrate the achievement of good robust performance.

• Culinary science and hospitality research
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• v.13 no.1 s.32
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• pp.75-86
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• 2007

This study was carried out to find out the effect of food hygiene awareness on kitchen employees' performance in the banquet cuisine of five-star hotels in Seoul. 279 kitchen employees were asked to fill out the questionnaire, and the collected data were analyzed by SPSS package(version 11.0). First, results of analysis on food hygiene showed that there were four factors, each respectively named as, food security regulations, food storage, period of circulation of food, and food safekeeping. Second, after analyzing each item in whole according to each of the factors, the average degree of priority on food hygiene in general was 4.52. Results according to each of the elements showed that food security regulations(4.56) and period of circulation of food(4.55) were considered as a priority. After analyzing the difference between the degree of priority and degree of performance according to each of the factors, it was found out that the latter was significantly lower than the former in all factors. Third, after analyzing the difference of food hygiene priority in accordance with general characteristics, statistically significant difference was only shown in education(F=3.308, p<0.05) and class(F=4.418, p<0.01). Fourth, after analyzing the difference of food hygiene performance in accordance with general characteristics, the only significant difference was found in food security regulation of education(F=4.418, p<0.01) and food security regulation of class(F=3.859, p<0.01). Fifth, after analyzing the effect of cook's awareness of priority on food hygiene on the degree of performance, it was found out that the awareness of priority on food hygiene had a positive effect(+) on the degree of performance. Therefore, we can conclude that as kitchen employees recognize the priority on the food hygiene better, their degree of performance was higher.

• Journal of the Korean Society of School Health
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• v.28 no.1
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• pp.10-21
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• 2015

Purpose: In this study, the research has been conducted on the health teachers and general teachers who are in charge of sexual education in the middle schools to find out their understanding on the degree of importance and degree of performance on key concept of the sex education and then compare their differences in the recognition of sex education which leads to find out the contents and range of capabilities required for the teachers in charge of sex education. Methods: A descriptive research on 77 health teachers and 71 general teachers using IPA and SPSS/WIN was practiced. Results: The result of research showed that there are significant differences in the annual hours for sex education of their schools, the contents of the sex education which was given in the lecture type lesson, and their performance degree. It was also found the distribution of key concepts by differences in IPA matrix. Conclusion: As there are the differences in the performance degree in sex education between health teachers and general teachers in middle school, more specific education for each of them is needed. And the way to reinforce the key concepts, which are found high in perceived importance degree for both health teachers and general teachers, but low in the performance degree should be considered.

• The Journal of Information Systems
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• v.28 no.1
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• pp.73-96
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• 2019

Purpose The purpose of this study is to examine the effect of communication-structure characteristics on performance in online collaboration using the data from Github, one of representative open source software development platforms. We analyze the impact of in-degree/out-degree centralization and reciprocity of communication network on collaboration performance in each project. In addition, we investigate the moderating effect of owner types, an individual developer or an organization. Design/methodology/approach We collect the data of 838 Github projects, and conduct social network analysis for measuring in-degree/out-degree centralization and reciprocity as independent variables. With these variables, hierarchical regression analysis is employed on the relationship between the characteristics of communication structure and collaborative performance. Findings Our results show that for the project owned by an organization, the centralized structure of communication is not associated with the collaboration performance. In addition, the reciprocity is positively related to the collaboration performance. On the other hand, for the project owned by an individual developer, the centralized structure of communication is positively related to the performance, and the reciprocity does not show the positive relationship on the performance.

• Journal of Korean Institute of Industrial Engineers
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• v.40 no.5
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• pp.451-461
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• 2014

This paper analyzed the degree of perception and performance of technology-humanities convergence in Korean SMEs. First, the meaning and activities of technology-humanities convergence were defined. Second, a survey data was collected from 277 Korean SMEs and analyzed from two perspectives-degree of performance and degree of perceived importance. Finally, based on the results, this paper signposted the important points to activate the technology-humanities convergence in SMEs.

• The Mathematical Education
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• v.30 no.1
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• pp.59-66
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• 1991

This paper considers the problem of determining how degree examinations' project which consumes a very significant time of the student and his supervisor affect bib overall degree performance and sifts among students of varying performance: particularly at the university level. A survey sampling method for data collection and techniques for analysis are discussed and results show degree project u a poor discriminator.

• International Commerce and Information Review
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• v.10 no.4
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• pp.3-21
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• 2008

This study analyzed the effect of degree of using online trade process services provided by e-Trade companies on the degree of user satisfaction and the online export performance in Korean small and medium-sized exporting firms(SMEs). According to the empirical survey results based on 130 sample firms, there were positive relationship among the frequency of using e-Trade companies' services, the degree of user satisfaction and the online export performance. Furthermore, the results of the moderated regression analysis showed that there were significant moderation effect of the organizational characteristics on the relationships between the degree of user satisfaction and the SMEs' online export performances. This study provides several useful implications to Korean SMEs, e-Trade companies and government policy makers.