• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.346-350
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• 2001

PMSM drives are widely used in the industrial and residential applications because of high efficiency, high power density and high performance. For better performance of PMSM, however, torque ripples should be reduced. This paper investigates a reduction of torque ripple due to the unsinusoidal flux linkage produced by the shapes of stator slot and magnetic pole. To minimize torque ripple, a simple flux estimator is proposed. This method interatively compensates the distributed flux linkage from an error between the measured and estimated currents. The proposed algorithm is verified through simulation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.180-185
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• 2004

Unlike industrial manipulators, the manipulators mounted on the service robots are interacting with humans in various aspects. Therefore, safety has been the important design issue. Many compliant robot arm designs have been introduced for safety. It is known that passive compliance method has faster response and higher reliability than active ones. In this paper, a new safe mechanism based on passive compliance has been proposed. Passive mechanical elements, specifically transmission angle of the 4-bar linkage, springs and shock absorbing modules are incorporated into this safe mechanism. This mechanism works only when the robot arm exerts contact force much more than the human pain tolerance. Validity of the safe mechanism is verified by simulations and experiments. In this research, it is shown that the manipulator using this mechanism provides higher performance and safety than those using other passive compliance mechanisms.

• Journal of Digital Convergence
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• v.6 no.2
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• pp.107-115
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• 2008

This paper aims to examine the main factors of the job embeddedness on organizational citizenship behavior and job performance. To accomplish these purposes, the main factors of the job embeddedness such as fit, linkage, and sacrifice were found from the previous studies. The questionaries of 250 were distributed to the employees working at the Gumi Industrial Complex. The questionaries of 220 were obtained and 204 were analyzed through frequencies, correlation and multiple regression. The results of this study are as follows; First, we conducted exploratory factor analysis for three constructs (fit, linkage, and sacrifice) using oblique rotation method that did not assume independence among the factors and main factors of job embeddedness were grouped together by three factors. Second, it is shown that three main factors of job embeddedness have a positive influence on the organizational citizenship behavior and job performance (p<0.05). This study, however, have limitations of number of sample and survey area. The future study should consider these limitations in improving model applicability in practice.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.918-920
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• 2001

PMSM drives are widely used in industrial and residential applications because of high efficiency, high power density and high performance. For better performance of PMSM, however, torque ripples should be reduced. This paper investigates a reduction of torque ripple due to the unsinusoidal flux linkage produced by the shapes of stator slot and magnetic pole. To minimize torque ripple, a simple flux estimator is proposed. This method iteratively compensates the distributed flux linkage from an error between the measured and estimated currents. The proposed algorithm is verified through simulation.

• 한국디지털정책학회:학술대회논문집
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• 2006.06a
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• pp.77-86
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• 2006

This paper aims to examine the main factors of the job embeddedness on organizational citizenship behavior and job performance. To accomplish these purposes, the main factors of the job embeddedness such as fit, linkage, and sacrifice were found from the previous studies. The questionaries of 250 were distributed to the employees working at the Gumi Industrial Complex. The questionaries of 220 were obtained and 202 were analyzed through frequencies, correlation and multiple regression. The results of this study are as followings; First, we conducted exploratory factor analysis for three constructs (fit, linkage, and sacrifice) using oblique rotation method that did not assume independence among the factors and main factors of job embeddedness were grouped together by three factors. Second, it is shown that three main factors of job embeddedness have a positive influence on the organizational citizenship behavior and job performance (p<0.05). This study, however, have limitations of number of sample and survey area. The future study should consider these limitations in improving model applicability in practice.

• Applied Chemistry for Engineering
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• v.8 no.2
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• pp.147-153
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• 1997

Bismaleimides(BISMI) containing ester linkages were prepared by the chlorinated N-(p-carboxyphenyl)maleimide and N-(p-hydroxyphenyl)maleimide. The photosensitive properties of BISMI were investigated via changes of the irradiation time. Benzil dimethyl ketal was used as a photoinitiator. The effect of photoinitiator onto BISMI increase in average as increasing photoinitiator concentration and irradiation time. The yield of residual film and image pattern and resolution also measured and discussed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.11 s.242
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• pp.1534-1541
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• 2005

Unlike industrial manipulators, the manipulators mounted on service robots are interacting with humans in various aspects. Therefore, safety has been one of the most important design issues. Many compliant robot arms have been introduced for safety. It is known that passive compliance method has faster response and higher reliability than active ones. In this paper, a new safety mechanism based on passive compliance is proposed. Passive mechanical elements, specifically transmission angle of the 4-bar linkage, springs and shock absorbing modules are incorporated into this safety mechanism. This mechanism works only when the robot arm exerts contact force much more than the human pain tolerance. Validity of this mechanism is verified by simulations and experiments. It is shown that the manipulator using this mechanism provides higher performance and safety than those using other passive compliance mechanisms or active methods.

• Environmental and Resource Economics Review
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• v.11 no.4
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• pp.581-608
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• 2002

The electric power industry has played an important role in dramatic economic development in Korea and the electricity has constituted a critical factor sustaining the well-being of the Korean people. This study uses input-output analysis to investigate the role of four electric power sectors (hydroelectric, fossil-fuels, nuclear and non-utility) in the Korean national economy for the period 1985~1998, focusing on four topics: the impacts of electricity supply investments, the electricity supply shortage effects, and the impacts of the rise in electricity rates, and the inter-industry linkage effect. The overall results reveal that non-utility electric sector is superior in terms of the national economy-wide effects to other three sectors throughout the period. Finally, potential uses of the results are illustrated from the perspective of policy instruments and some policy implications are discussed.

• International Journal of Advanced Culture Technology
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• v.9 no.4
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• pp.110-117
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• 2021

The purpose of the study is to develop effective teaching methods to strengthen the major learning capabilities of electronic engineering learners through inquiry learning using computing thinking ability. To this end, first, in the electronic engineering curriculum, we performed teaching-learning through an inquiry and learning model related to mathematics, probability, and statistics under the theme of various majors in electronic engineering, focusing on understanding computing thinking skills. Second, an efficient electronic engineering subject inquiry class operation using computing thinking ability was conducted, and electronic engineering-linked education contents based on the components of computer thinking were presented. Third, by conducting a case study on inquiry-style teaching using computing thinking skills in the electronic engineering curriculum, we identified the validity of the teaching method to strengthen major competency. In order to prepare for the 4th Industrial Revolution, by implementing mathematics, probability, statistics-related linkage, and convergence education to foster convergent talent, we tried to present effective electronic engineering major competency enhancement measures and cope with innovative technological changes.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.251-252
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• 2021

With the recent emergence of the 4th Industrial Revolution, the government is promoting the development of smart construction technology and institutional improvement through various policies to induce cutting-edge and technological innovation in the construction industry. As part of such smart construction technology, the application of BIM is being activated, and related regulations and guidelines are constantly being supplemented. In relation to BIM, there are many studies on the fields of library, design standards etc., but research on specific unit price utilization and unit price DB construction for calculating construction cost is insufficient. Therefore, in this study, a basic study was conducted on the linkage of the construction standard market unit price and the BIM library. Based on the basic research conducted in the future, we intend to establish specific standards for calculating BIM-based construction costs.