• Journal of the Earthquake Engineering Society of Korea
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• v.11 no.2 s.54
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• pp.47-56
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• 2007

In this study, tile performance of a passive tuned mass damper (TMD) and a semi-active tuned mass damper (STMD) was evaluated in terms of seismic response control of elastic and inelastic structures under seismic loads. First, elastic displacement spectra were obtained for the damped structures with a passive TMD, which was optimally designed using the frequency and damping ratio presented by previous study, and with a STMD proposed in this study. The displacement spectra confirm that STMD provides much better control performance than passive md with less stroke. Also, the robustness or the TMD was evaluated by off-tuning the frequency of the TMD to that of the structure. Finally, numerical analyses were conducted for an inelastic structure of which hysteresis was described by Bouc-Wen model and the results indicated that the performance of the passive TMD of which design parameters were optimized for a elastic structure considerably deteriorated when the hysteretic portion or the structural responses increased, while the STMD showed about 15-40% more response reduction than the TMD.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.3
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• pp.48-54
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• 2015

In this study, we propose an innovative lateral force distribution building system between tall buildings by utilizing the difference of moment of inertia, resulting the reduction of lateral displacement and the lateral forces in terms of an alternative for the dense human and increased cost of lands in highly integrated city area. A successive collapse prevention means by providing additional bearing plate between connections is proposed. In addition to that, a more economical vibration reduction is expected due to the suggested tuned mass damper on the surface of spacial structure. In the considered verification examples, reduced drifts at the top location of the building systems are validated against static wind pressure loads and static earthquake loads. The suggested hybrid building system will improve the safety and reliability of the new or existing building system in terms of more than 30% reduced drift and vibration through the development of convergence of tall buildings and spatial structures.

• Journal of the Korean Institute of Intelligent Systems
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• v.12 no.1
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• pp.33-38
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• 2002

In this paper, a Two-Degree-of-Freedom-Controller(TDFC) for DC motors based on inverse dynamics and the fuzzy technique is presented. The proposed controller includes the inverse dynamic model of a DC motor system, a prefilter and a fuzzy compensator. The model of the system is characterized by a nonlinear equation with coulomb friction. The prefilter eliminates high frequency effects occurring when the inverse dynamic model is implemented. The fuzzy compensator is designed for tracking the change of the reference input and simultaneously regulating the error between the reference input and the system output which can be caused by disturbances. The optimal parameters of both the model and the compensator are identified by a real-coded genetic algorithm. An experimental work on a DC motor system is carried out to verify the performance of the proposed controller.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.6
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• pp.842-848
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• 2008

This paper deal with uncertainty problem by using Type-2 fuzzy logic set for nonlinear system modeling. We design Type-2 fuzzy logic system in which the antecedent and the consequent part of rules are given as Type-2 fuzzy set and also analyze the performance of the ensuing nonlinear model with uncertainty. Here, the apexes of the antecedent membership functions of rules are decided by C-means clustering algorithm and the apexes of the consequent membership functions of rules are learned by using back-propagation based on gradient decent method. Also, the parameters related to the fuzzy model are optimized by means of particle swarm optimization. The proposed model is demonstrated with the aid of two representative numerical examples, such as mathematical synthetic data set and Mackey-Glass time series data set and also we discuss the approximation as well as generalization abilities for the model.

• Journal of Regulation Studies
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• v.27 no.2
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• pp.71-104
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• 2018

Regulatory agencies' response to resource constraints is an important issue in terms of regulatory effectiveness, but systematic research is lacking. As an effort to overcome this limitation, this study was to explore behaviors of regulatory agencies in response to resource constraints. Reviewing the precedent studies based on regulatory and organizational theories, the study suggested the potential behaviors of regulatory agencies under resource constraints: changes in regulatory processes, changes in enforcement methods, decoupling, and regulatory delegation and contracting-out. The study also discussed the realistic explanations of the response behaviors partly through the case of marine transportation regulation, and explained the problems that the regulatory agency's behaviors could bring about. Based on the findings, the study suggested that the regulatory framework should be designed to ensure the effectiveness of the regulatory system in consideration of the regulatory agencies' behaviors under resource constraints. The study is expected to contribute to developing a theoretical analysis framework ultimately for an empirical study in the future.

• Journal of Music and Human Behavior
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• v.12 no.2
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• pp.19-36
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• 2015

The purpose of this study was to examine the effects of rhythmic auditory stimulation (RAS) on gait parameters, with and without the presence of a melody, for adolescents with traumatic brain injury (TBI). Three adolescents with TBI received a total of ten individual RAS training sessions. At pre and posttest, spatiotemporal parameters including cadence, velocity and kinematic parameters were measured using the VICON 370 Motion Analysis System. The results showed no significant difference in gait velocity between the two conditions, thus the presence of the melody condition did not impact the outcome of RAS gait training. On the other hand, all participants showed improvement in gait function after RAS training. The cadence, velocity, stride length, and symmetry were increased and the stride time was reduced after training. The motion analysis demonstrated that the movement patterns of hip and knee joints improved, as they were more similar to normal gait, which indicates that the walkings tance became more stable. The research findings indicate that rhythm is the primary factor in mediating gait functions via RAS training. This study also supports that RAS training can effectively improve the gait function for adolescents with TBI.

• The Journal of Korean Philosophical History
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• no.35
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• pp.109-129
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• 2012

At this point, in Confucianism's schools debated about analysis for early theory and latterly it of nature between human and animal in Nongam Kim Changhyob's Confucianism. Oh Heeshang argued early theory about Shanguzaezungyongmunmok, written by Kim Changhyob, and establishment of theory about Yokuonyudozaelonshabyonnokbyon, written by him. Kim Changhup, brother of Kim Changhyob, argued so early theory about Shanguzaezungyongmunmok. O Yubong, student of Kim Changhyob, argued establishment of theory about Sobyon and Zabzee, written by Kim Changhyob. While, Yim Songzu argued early theory and establishment of theory about Zabzee. As a result, presenting researchers argued the same as. That is, they interpret early theory about difference of nature between human and animal in Kim Changhyob. they interpret about the same of nature between human and animal in it. However, Kim Changhyob wrote difference of nature between human and animal in Shanguzaezungyongmunmok. While, he wrote difference it and the same it in Yokuonyudozaelonshabyonnokbyon. He thought the same li between human and animal. However, he thought difference hyongki them. Furthermore, He wrote difference it and the same it in Zabzee. Therefore, they had depended on Kim Changhyob. As a result, posterity scholars interpreted early theory and establishment of theory about his theory. they depended on his authority. However, he changed himself theory.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.12
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• pp.1956-1964
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• 2009

Understanding ethical fashion consumers in Korea is essential for the expansion of the ethical fashion market. This study analyzed ethical consumers in Korea in an examination of the factors that influence ethical purchase behavior and attitudes. The differences between ethical fashion consumers and non-ethical fashion consumers were investigated using eight variables (perceived consumer effectiveness (PCE), self-direction, benevolence, universalism, social responsibility, perceived behavioral control, face saving, and group conformity). Data were collected by means of a questionnaire through both on-line and off-line surveys from April 20 to June 7, 2009. Only the respondents knowledgeable of ethical products or ethical consumption were asked to complete the questionnaire. A total of 494 samples were used for analyses. Using independent samples t-test, the differences in each variable between two groups were examined. There were significant differences between ethical fashion consumers and non-ethical fashion consumers in attitudes toward ethical consumption behavior, behavioral intention, PCE, self-direction, universalism, social responsibility, and face saving variables. The factors influencing attitude and behavior intention were investigated by step-wise regression analyses. For ethical fashion consumers, the attitudes to ethical consumption behavior were largely influenced by PCE and benevolence. Social responsibility was the most predictable variable in guiding behavioral intention. Behavioral intention was also influenced by benevolence and attitude. Group conformity was found to be negatively correlated with behavioral intention. The findings of this study provide significant guidance for marketers of ethical fashion products. This study is the start of ethical fashion consumer research in Korea and can develop into variable subfields in the future.

• Progress in Medical Physics
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• v.21 no.2
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• pp.174-182
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• 2010

In this study, we evaluated feasibility of applying MTV (Metabolic Target Volume) to respiratory gated radiotherapy for more accurate treatment using various SUV (Standard Uptake Value) from PET images. We compared VOI (Volume of Interest) images from 50%, 30% and 5% SUV (standard uptake volume) from PET scan of an artificial target with GTV (Gross Tumor Volume) images defined by percentage of respiratory phase from 4D-CT scan for respiratory gated radiotherapy. It is found that the difference of VOI of 30% SUV is reduced noticeably comparing with that of 50% SUV in longitudinal direction with respect to total GTV of 4D-CT image. Difference of VOI of 30% SUV from 4D-PET image defined by respiratory phase from 25% inhalation to 25% exhalation, and GTV from 4D-CT with the same phase is shown below 0.6 cm in maximum. Thus, it is better to use 4D-PET images than conventional PET images for applying MTV to gated RT. From the result that VOI of 5% SUV from 4D-PET agrees well with reference image of 4D-CT in all direction, and the recommendation from department of nuclear medicine that 30% SUV be advised for defining tumor range, it is found that using less than 30%SUV will be more accurate and practical to apply MTV for respiratory gated radiotherapy.

• Management & Information Systems Review
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• v.29 no.2
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• pp.97-118
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• 2010

This paper explores the mean and volatility spillover effects among Chinese, Korean, and the U.S. stock markets during the Asian and global financial crises. We found that, during the Asian Financial crisis, there was no mean spillover effect to the Chinese stock markets. However, there were reciprocal mean spillover effects between the U.S. and the Korean market. This implies that Korean market was open, while Chinese market was secluded from the international financial market at that time. The negative volatility spillover effect between the U.S. and China reinforces this finding. During the global financial crisis, there was reciprocal mean spillover effect between the U.S. and China, and between the U.S. and Korea. This may reflect the fact that Chinese market has opened to the international financial market. However, the volatility spillover effect does not exist between China and the U.S., while the U.S. and Korea has reciprocal volatility spillover effect to each other. These findings may imply that China is still in the process of opening her stock market to international investors.