• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.7
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• pp.824-831
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• 1999

This paper presents new methods to resolve the important limits in the decoupled UPFC model for power flow, by which conventional power flow program can be performed with addition of two buses per one UPFC. In order to operate UPFC to the desired value, the series voltage and shunt current of UPFC should be computed. So a method of calculating these by simple equations after power flow is derived. However, the calculated magnitude of series voltage and/or shunt current of UPFC may not be allowed because of the UPFC limit \ulcorner to the ratings of inverters. In this case, the active power and the reactive power (or the voltage magnitude) of UPFC buses should be revised to resolve the limit. This paper proposes the Newton Raphson method to resolve these limits. Particularly, when resolving the series voltage magnitude, three strategies are proposed according to the priority of the active power and the reactive power (or the voltage magnitude).

• The Transactions of the Korea Information Processing Society
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• v.4 no.2
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• pp.515-522
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• 1997

A neat prefect stable random access protocol for a broadcast channel,the distributed queuing random access protocol(DQRAP)is presented and evaluated.The DQRAP prootcol utilizes minisolts to provide termaty chan-nel feedback and two distributed queues to:9a) resolve contention and (b) to schedute the transmission of messages.Three minislots are sufficient to resolve collisions faster than the tranmission times of all inboled mecages.Three minislots are suffcient to resolve collisions faster than the tranmission times of all inbolved arrivals when ternary minislot feedback is used.Modelingand simulation indicate that the DQRAP protocol, using as few as three minislits,achives a performance level which approaches that of hypothetical perfect cheduling protocol,ie,the M/D/I system,with respect to propagation delay,thus offers the potential of improved performance over current protocols in satellite,metropolitan and packet radio networks.

• Journal of The Korean Association For Science Education
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• v.24 no.2
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• pp.408-415
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• 2004

The purpose of this study is to investigate the effect of the delayed resolution of cognitive conflict on middle school students' conceptual change in learning the concept of the action and reaction with cognitive conflict strategy. The subjects were divided into 3 groups according to the time in which teacher tried to resolve cognitive conflict: instant resolution group, 2-day delay resolution group, and 7-day delay resolution group. Pretest, just before test, posttest, and delayed posttest were examined to measure the degree of conceptual change. Delay resolution groups' students answered the questionnaire asking what they had done to resolve cognitive conflict during the period which had been delayed resolution of cognitive conflict. The results of this study were as follows. First, instant resolution group showed significantly more scientific conceptual change than delay resolution groups. Secondly, most of delay resolution groups' students who tried to resolve cognitive conflict interacted with their peers. Also, delayed resolution of cognitive conflict was not helpful to resolve cognitive conflict. Thirdly, in delay resolution groups, we found the tendency that students who spent more than 30 minutes trying to resolve cognitive conflict altered their preconceptions into scientific concepts more easily than the others did. According to the results of this study, instant resolution of cognitive conflict is more effective on scientific conceptual change than delayed resolution of cognitive conflict.

• Journal of the Korean Professional Engineers Association
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• v.29 no.5
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• pp.11-23
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• 1996

• Korean Architects
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• s.631
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• pp.140-149
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• 2021

• Korean Architects
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• s.628
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• pp.126-135
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• 2021

• Journal of the military operations research society of Korea
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• v.23 no.2
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• pp.85-102
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• 1997

There have been several research efforts to support interoperability among multiple databases. In integrating multiple databases, we must resolve schema conflicts due to the heterogeneity in databases. To resolve these conflicts, not only meta-data for database schemas but also general knowledge expressing the real world meanings associated with the database schemas are required. This paper presents a uniform representation method for relational schema and general knowledge base that is composed, among other things, of concept hierarchy and thematic roles in relationship, using the knowledge representation language Lk. This representation method has a flexible descriptive power which facilitates concepts to be expressed at different levels of granularity and can describe knowledge expressed in Lk are used for input of the next step, such as conflict resolution and query processing of multiple database.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.234-239
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• 1993

Most of the control problem is for the redundant manipulators use the pseudo-inverse control, thit is, the redundancy is resolved by the pseudo-inverse of the Jacobian matrix and then the controller is designed based on this resolution. However, this pseudo-inverse control has some problems when the redundant robot repeats the cyclic tasks. This is because the pseudo-inverse resolution is a local solution that generates the different configurations of the robot arm for the same hand position. Therefore it is necessary to find the global solution that maintains the optimal configuration of the robot for the repetitive tasks. In this paper, we want to propose a redundancy resolution method by the optimal theory that uses the calculus of variation. The problem formulations are : first to convert the optimal resolution problem to an optimal control problem and then to resolve the redundancy using the necessary conditions of optimal control.

• The Journal of Fisheries Business Administration
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• v.38 no.1 s.73
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• pp.19-45
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• 2007

There have not been many studies which considered both quantitative and qualitative location factors on the issues of site selection problems for a fish farm. This study develops AHP(analytic hierarchy process) model to resolve site selection problem for a fish raising farm by using quantitative and qualitative factors. In order to evaluate the validity of the location factors found in the literature review, the study used advice from fish raising farmers and related academic experts. Four major factors have been selected as economic factors, social factors, natural environmental factors and infrastructures. An AHP structural diagram has developed by considering the factors and potential sites proposed for fish farming. Through the survey on the preference of factors and potential sites, pairwise comparison matrices have been estimated and used to calculated the relative weights of each potential site. The AHP model process shown in the study can be applied to resolve site selection problems for fish raising farmers.

• Korean Journal of Health Education and Promotion
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• v.10 no.2
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• pp.22-31
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• 1993

Presently, in the countries, such as America and Japan which are better in socio-economical conditions than Korea, in Taiwan which is similar in them to us, and even in Thailand and Philippine which are thought lower in them, health education is taught as one of curricular subjects in elementary and secondary school levels. In Korea, however, the importance of teaching health education as a curricular subject has been recognized among many professionals of health since a long time ago. Along with current rapid development of polytechnique and industry, various kinds of serious health hazard have appeared even in our daily life, so it has been urgently needed that people have comprehensive knowledge and skills to resolve one's own health problems. Among various conditions needed to resolve the health problems in our society, it is one of the most effective precedures that health education is taught as a curricular subject at least in elementary and secondary school levels. For this, the followings are inevitable ; reformation of school health organization and laws involving health, development of teaching materials in health and training of health educators.