• Journal of the Korean Society for Precision Engineering
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• v.30 no.11
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• pp.1121-1128
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• 2013

Ultrasonic grinding system is that the ultrasonic vibration by ultrasonic actuator is applied on conventional grinding system during grinding process. The Ultrasonic vibration with a frequency of over 20kHz can reduce grinding forces and increase surface quality, material removal rate (MRR) and grinding wheel life. In addition, ultrasonic vibration assisted grinding can be used for the materials that are difficult to cut. In this paper, methodology for ultrasonic tools is studied based on finite element method, and in turn the ultrasonic tools are designed and fabricated. It is found that the ultrasonic tool can vibrate with a frequency of 20kHz and amplitude of $25{\mu}m$. In order to verify the machining performance, the grinding experiment is performed on titanium alloy. By applying ultrasonic vibration, the grinding force and temperature are reduced and MRR is increased compared with the conventional grinding.

• Journal of the Korea Convergence Society
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• v.6 no.2
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• pp.1-11
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• 2015

Objectives: The purpose of this study was to explore the experience process of nursing students who have participated in a major converged short-term study abroad program and to present the future direction of short-term study abroad. Methods: This study is a qualitative study based on the grounded theory and method in nursing students' experience of major in a major converged short-term study abroad program. Results: The core category emerged as 'finding myself in another me'. 'as experience the difference' emerged as a causal condition. Action/interaction strategies were found to provide students with these effects: 'a change of attitude on life', 'find continued support resources', 'due to hard reality, putting down the aspiration'. Shown in these results of this study, nursing students were seen to have the simultaneous effect of 'to live as the organizers of life', and 'return to the old life'. Conclusions: The nursing students experience a positive impact on their attitude towards life.

• Journal of Convergence for Information Technology
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• v.8 no.6
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• pp.305-315
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• 2018

The purpose of this study is to investigate the relationship between university students' interest in appearance management and various forms of appearance management behaviors converged with beauty trends. The questionnaire was distributed for 15 days from April 15 to 30, 2018 to the students in the G district. The data of 267 students who explained and agreed on the purpose and method of the study were analyzed using SPSS 18. University students' interest in appearance management showed a difference of interest according to university students, male and female students in body composition management, skin care, hair care, and cosmetics use management except for interest in health care. In addition, students with a high level of interest in managing cosmetics use had a positive effect on the degree of interest in managing cosmetics usage in fashion styles, cosmetics style, skin care, and body management behavior factors that were converged with trends. And negative (-) influence on the use of health equipment. Based on the study of the trend management behaviors of college students, I will expect to utilize the reference materials for new product development research of the beauty industry and will continue to study the new management mode of appearance management.

• The Journal of the Korea Contents Association
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• v.22 no.7
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• pp.583-598
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• 2022

This study is a follow-up study of the Social Media Emotional Contagion(SECS) and it aims to validate the Social Media Emotional Contagion Scale(SECS) through CFA and criterion-related validity. The data was collected from 326 people in 20s. The criterion-related validity of SECS were confirmed with the Korean version of the Emotional Contagion Scale(K-ECS), the Basic Empathy Scale in Adult(BES-A), and the Rosenberg Self-esteem Scale(SES). As a result, the K-ECS and sub-factor of Emotional Contagion of BES-A, which are the same as the construction of SECS, converged. Other scales were differentiated from SECS. However, sub-factor of SES of positive self-esteem, which are the same as the construction of SECS, converged. Also, sub-factor of SES of negative self-esteem, which are the same as the construction of SECS of negative Emotional Contagion, converged. Finally, the significance and limitations of this study and future studies were discussed.

• Convergence Security Journal
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• v.19 no.5
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• pp.85-90
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• 2019

The purpose of this study is to analyze the trend of exercise intervention applying various devices to increase the physical activity of the disabled, and to suggest the exercise intervention using converged devices that meet the needs of the times due to the increase of elderly people with disabilities. Exercise intervention using converged devices applicable to the disabled is divided into two types: first, exercise intervention using virtual reality-based gamification, and second, exercise intervention based on wearable devices of wearable or body-attached such as bands and watches. For exercise intervention using converged devices that can be enjoyed by the elderly with disability, minimize of environmental limitations, and easy to personalize, there is a need for configuration requirements such as easy operation and simple rules of operation, easy device installation and wearing, a trainer who can complement immature device utilization. In order to maintain and improve the daily living performance of the elderly with disabilities who experience a significant decrease in their cognitive and physical functions, it is necessary to use a physical activity game that can be experienced and can be interested in everyday life or a variety of devices to increase the amount of physical activity.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.584-584
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• 2006

• Journal of the Ergonomics Society of Korea
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• v.31 no.2
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• pp.299-308
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• 2012

Objective: This study presents the conceptual framework and the conceptual model to account for user experience by expanding the existing concepts of usability, in particular considering the user-interface environment in digital convergence. Background: To better understand a variety of users interacting with a converged product based on digital technologies, there seems to be a limit to consider the existing concepts of usability. All possible aspects of user's interaction with a product in a context of use need to be taken into consideration. Method: This study identifies the concept of user experience through a comprehensive literature review. Results: First, this study reviews the existing concepts of usability and user experience. And then this study describes four main components in the conceptual framework of user experience: user's internal states, user's external states, a product, and various outcomes, each of which encompasses distinct sub-components. The conceptual model of user experience accounts for how user's internal states change over time and for how different sub-components affect actual behavior of use. Conclusion: It is expected that these user experience concepts can be used in basic resources to better understand different behavioral characteristics of users and to better design interactive products in converged digital environments.

• Korean Journal of Computational Design and Engineering
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• v.21 no.1
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• pp.9-19
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• 2016

Applying human engineering simulation to analyzing work capability and movements of operators during manufacturing is highly demanded. However, difficulty in modeling digital human required for simulation makes engineers to be reluctant to utilize human simulation for their tasks. This paper addresses such problem on human engineering simulation by developing the technology to automatize human modeling with multiple Kinects at different depths. The Kinects enable us to acquire the movements of digital human which are essential data for implementing human engineering simulation. In this paper, we present a system for modeling automation of digital human. Especially, the system provides a way of generating the digital model of workers' movement and position using multiple Kinects which cannot be generated by single Kinect. Lastly, we verify the effects of the developed system in terms of modeling time and accuracy by applying the system to four different scenarios. In conclusion, the proposed system makes it possible to generate the digital human model easily and reduce costs and time for human engineering simulation.

• Journal of Environmental Impact Assessment
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• v.19 no.3
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• pp.297-305
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• 2010

This study has intended to analyze the nature of the errors that occur as a result of shadows during the process of NDVI calculation using high-resolution satellite images of Cheongju City, in order to calibrate such errors, and to verify the results. This study has calibrated the shadow errors by utilizing the relationship between the Greenness above Bare Soil (GRABS) calculated through Tasseled-Cap transformation and the original NDVI. To verify the accuracy of the results, this study has compared the shadow area extracted by the difference between before and after calibration of NDVI, with the original shadow area. The NDVI value converged on the value of -1.0, representing water, because shadow areas could not accept the reflection value from each band. However, after performing Tasseled-Cap transformation, the NDVI of shadow areas that had converged on -1.0 prior to calibration had increased to a level similar to the NDVI of neighboring areas. In addition, the average NDVI in general had increased from -0.08 to -0.01. Finally, the shadow area drawn out was almost matched to the original one, meaning that the NDVI calibration method employed turned out to be highly accurate in extracting shadow areas.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.55 no.8
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• pp.375-377
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• 2006

An adaptive IIR filter in ANC(Active Noise Control) systems is more effective than an adaptive FIR filter when acoustic feedback exists, in which cause an order of an adaptive FIR filter must be very large if some of poles of the ideal control filter are near the unit circle. But the IIR filters may have stability problems especially when the adaptive algorithm for adaptive filters is not yet converged. In this paper, a stabilized multi-channel recursive LMS (MCRLMS) algorithm for an adaptive multi-channel IIR filter is presented. RLMS algorithms usually diverge before the algorithm is not yet converged. So, in the beginning of the ANC system, the stability of the RLMS algorithms could be improved by pulling the poles of the IIR filter to the center of the unit circle, and returning the poles to their original positions after the filter converges. Computer simulations and experiments for dipole ducts using a TMS320C32 digital signal processor have performed to show the effectiveness of a proposed algorithm.