• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.620-628
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• 2005

Spatial control of sound is essential to deliver better sound to the listener's position in space. As it can be experienced in many listening environments, the quality of sound can not be manifested over every position in a hall. This motivates us to control sound in a region we select. The primary focus of the developed method has to do with the brightness and contrast of acoustic image in space. In particular, the acoustic brightness control seeks a way to increase loudness of sound over a chosen area, and the contrast control aims to enhance loudness difference between two neighboring regions. This enables us to make two different kinds of zone - the zone of quiet and the zone of loud sound - at the same time. The other perspective of this study is on the direction of sound. It is shown that we can control the direction of perceived sound source by focusing acoustic energy in wavenumber domain. To begin with, the proposed approaches are formulated for pure-tone case. Then the control methods are extended to a more general case, where the excitation signal has broadband spectrum. In order to control the broadband signal in time domain, an inverse filter design problem is defined and solved in frequency domain. Numerical and experimental results obtained in various conditions certainly validate that the acoustic brightness, acoustic contrast, direction of wave front can be manipulated for some finite region in space and time.

• Safety and Health at Work
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• v.13 no.1
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• pp.3-8
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• 2022

Background: This study aims to allow the development of efficient measures to improve occupational health of shift-working nurses focusing on job stress, health promotion behavior, resilience, and sleep disturbance. Methods: It was conducted on a subject panel of 137 nurses who were aware of the purpose of the study and agreed to participate. They worked three shifts at a tertiary hospital or a general hospital located in metropolitan city B. The collected data were analyzed by the independent t test and one-way analysis of variance and post-tested by Scheffe's test, Pearson's correlation coefficients, and multiple linear regression analysis using SPSS/WIN 25.0. Results: The significant influencing factors on sleep disturbance were of those whose subjective health status was 'normal' (b = 0.29, p < .001), 'not healthy' (β = .40, p < .001), who have job stress (β = .22, p = .003), and who have health promotion behavior (β = -0.17, p = .023). The overall explanatory power was 31.1% (F = 16.31, p < .001). Conclusion: Through this study, nurses' subjective health status and job stress of working shifts were found to be important factors influencing the sleep disturbance level, and the most influencing factor was identified as the subjective health status.

• Journal of Korea Trade
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• v.24 no.3
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• pp.55-72
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• 2020

Purpose - In this paper, we provide recommendations for Korea's long-term direction and strategic measures to attract inward foreign direct investment (FDI) in response to Japan's export regulations. In doing so, we analyze the current situation and characteristics of trade between Korea and Japan, focusing on the parts and materials industry, which is particularly affected by Japan's trade regulations. Design/methodology - Based on the analysis of five successful inward FDI cases (e.g. Toray, IGK, Delkor, GlobalWafers, DuPont) and statistic trend review in the parts and materials industry, we consider various factors pertaining to successful inward FDI in Korea and propose valuable investment attraction strategies. Findings - For a successful investment attraction strategy, we studied some statistical trends in the internal and external environments of the parts and materials industry and successful investment attraction cases in Korea. We have found that in order to increase the probability of success in attracting investment, we need a mid-to long-term strategy considering multiple factors such as "Production-oriented, Demand-linked, Global Value Chain (VGC) linked, and Policy-linked investment attraction." Originality/value - We suggest several specific measures and important strategic implications for the Korean government and firm's managers to attract inward FDI successfully.

• The Korean Journal of Franchise Management
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• v.5 no.1
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• pp.5-25
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• 2014

The impact of industry characteristics on born global firms'internationalization process is widely acknowledged. Even though there are studies focusing on other industries, the franchise industry's internationalization patterns have not been generally analyzed. Through a multiple case-study research focusing on a comparison between franchise and other industries, we are able to define "born-global franchise" in the internationalization pattern and specific influential factors. Our findings show that (1) leadership and creativity of executive, (2) learning orientation and technology orientation, (3) differentiated proprietary technology (4) observation of the surrounding environment.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.10
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• pp.2750-2767
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• 2023

Live Commerce is rapidly emerging as a new paradigm for the digital economy and consumption activities in the post-COVID era. Many prior studies have been conducted on Live Commerce, but studies focusing on the characteristics of sources of Live Commerce are insufficient. This study aimed to investigate the human factors of sources that affect consumers' intention to use Live Commerce. For this purpose, based on an expanded TAM (Technology Acceptance Model) through literature research, variables were set, and a survey was conducted targeting Korean consumers who have experienced purchasing products through Live Commerce. Excluding unreliable data, 201 responses were utilized in the analysis of this study. At first, the measurement tools were checked through validity and reliability verification, and correlation analysis was conducted to identify the relationships between variables. Then, the proposed hypotheses were verified through multiple regression analysis. As a result, firstly, the human factors of sources had a positive effect on PU (Perceived Usefulness). Secondly, the PEOU (perceived ease of use) had a positive effect on both PU and CS (Consumer Satisfaction). Thirdly, PU had a positive effect on CS and ITU (Intention to Use). Finally, CS with Live Commerce had a positive effect on the ITU. Through this study, we try to provide an understanding of consumer behavior in the Live Commerce environment and contribute to enhancing the service provider's ability to offer high-quality Live Commerce content.

• Journal of the Korea Society of Computer and Information
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• v.25 no.9
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• pp.143-150
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• 2020

The purpose of this study is to investigate the human error of bodyguards caused in the process of performing access control activities between security missions, focusing on multiple risk cases, and to suggest countermeasures accordingly. To verify this, after arranging the sequence of events in a time series, the VTA technique and Why-Why analysis technique that can easily identify the problem centered on the variable node were used. In addition, environmental factors and personal factors that cause human errors were extracted through M-SHEL Metrix. As a result of analyzing multiple risk cases through such a method, the security environment factors that cause access control accidents include lack of time (impatience), prejudice against visitors, intensive work methods, lack of security management, unattended travel, and familiar atmosphere. (Relaxation), formal work activities, convenience provision, and underestimation were surveyed. In addition, human errors caused by personal security guards were investigated as low alertness, formal work, negligence of inspection, and comfortable coping.

• Korean Journal of Child Studies
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• v.38 no.3
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• pp.75-90
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• 2017

Objective: This study aimed to identify children's cognitive processing and performance characteristics while multiple task performance. It confirmed whether their multiple task performance and psychological refractory period (PRP) varied by task condition (stimulus onset asynchrony [SOA] and task difficulty) and stimulus modality. Methods: Seventy 5-year-olds were recruited. Multi-task tools were developed using the E-prime software. The children were required to respond to two stimuli (visual or auditory) presented with microscopic time difference and their response times (RTs) were recorded. Results: As the SOA increased, the RTs in the first task increased, while the RTs in the second task and PRP decreased. The RTs of the first and second tasks, and the PRP for difficult tasks, were significantly longer than those for easy tasks were. Additionally, there was an interaction effect between the SOA and task difficulty. Although there was no main effect of stimulus modality, task difficulty moderated the modality effect. In the high difficulty condition, the RTs of the first and second tasks and PRP for the visual-visual task were significantly longer than those for auditory-auditory task were. Conclusion: These results inform theoretical discussions on children's multi-task mechanism, and the loss of multiple task performance. Additionally, they provide practical implications and information on the composition of multi-tasks suitable for children in educational environments.

• Korean Journal of Social Welfare
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• v.69 no.2
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• pp.247-269
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• 2017

This study aims to analyze multiple mediating effects of asset and self-esteem on the relationship between disability of household head and life satisfaction. This study used 9th panel data of KoWePS(Korean Welfare Panel Study) and employed path analysis with A-MOS. Research findings of this study are as follows: First, disability of household head had a negative effect on life satisfaction, total assets, and self-esteem. Second, we found not full but partial mediating effects of assets on the relationship between disability and life satisfaction. Third, similarly we found not full but partial mediating effects of self-esteem on the relationship between disability and life satisfaction. Finally, we found multiple partial mediating effects of assets and self-esteem on the relationships between disability and life satisfaction. The findings of this study suggest that financial education as well as asset management targeting persons with disability are necessary and very helpful to sustain their life satisfaction. In addition, we need to think about asset-building programs targeting persons with disability.

• Journal of Industrial Convergence
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• v.16 no.4
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• pp.27-32
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• 2018

In this research, in order to prevent the fire of multiple users who are concerned about many human life damage, based on the statistical data of the National Fire Protection Agency's National Fire Information Center and the Fire Defense Administration Fire Defense Administration, Attempts were made on the exploratory approach to measures that can reduce the topic of. In this research, using the preventive firefighting administrative statistics of the Fire and Disaster Management Agency, we analyzed by focusing on the effectiveness of multiple users' firefighting safety education. Through analysis results we could infer that fire safety education does not have effectiveness in actual fire prevention. Through previous research, we found out that the cause is insufficient for the management of fire safety education, thereby deriving an improvement plan to develop a systematic fire safety education system.

• Human Ecology Research
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• v.59 no.3
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• pp.325-340
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• 2021

The purpose of this study was to examine that multiple mediating effects of self-determination and self-efficacy in the relationship between the parental control and career maturity. In the study, 747 university students in Daegu, Busan and Seoul area were surveyed on their perceived level of parental control, career maturity, self-determination and self-efficacy. Data were analyzed using descriptive statistics, one-way ANOVA, and Pearson correlation analysis with SPSS 25.0 program, Hayes'Process Macro program and bootstrapping. The major results of this study were as follows; First, there were significant differences in college student's career maturity by grade, major, experience in career-related services and part-time job experience period. Second, there were significant correlations between parental control(behavioral control and psychological control), career maturity, self-determination and self-efficacy. Third, self-determination and Self-efficacy had multiple mediating effects in the relationship between parental control and career maturity. In conclusion, this study found multiple mediating effects of self-determination and self-efficacy in the relationship between parental control(behavioral control and psychological control) and career maturity. It was also found that parental behavioral control had a positive effect on career maturity by increasing self-determination and self-efficacy while parental psychological control had a negative effect on career maturity by decreasing self-determination and self-efficacy.