• 한국정밀공학회지
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• 제20권11호
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• pp.188-193
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• 2003

To predict changes in biomechanical parameters such as intradiscal pressure, and the shock absorbing mechanism in the spinal motion segment under different impact duration/loading rates, a three dimensional L3/L4 motion segment finite element model was modified to incorporate the poroelastic properties of the motion segment. The results were analyzed under variable impact duration for normal and degenerated discs. For short impact duration and a given maximum compressive force, relatively high cancellous pore pressure was generated as compared with a case of long impact duration, although the amount of impulse was increased. In contrast relatively constant pore pressure was generated in the nucleus. Disc degeneration increased pore pressure in the disc and decreased pore pressure in the cancellous core, which is more vulnerable to compressive fracture compared with intact case.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.323-327
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• 2001

Electrorheological(ER) and magnetorheological(MR) fluids have a unique ability to increase the dynamic yield stress of the fluid substantially when electric or magnetic field is applied. Controllable fluids such as ER and MR fluids have received considerable attention as several components of engineering devices. One of them is a smart impact damper using ER/MR fluids. Impact damper system can be used in the joint mechanism of railroad vehicle, protection equipment of elevator's drop, and launch equipment of aircraft. This paper presents the results of an analytical study of the performance of a smart impact damper to suppress vibration during impact excitation. The damping capabilities of MR impact damper for variable applied current are analyzed using Bingham model under sudden impact load.

• The Journal of Asian Finance, Economics and Business
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• 제7권3호
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• pp.295-302
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• 2020

The paper aims to investigate the impact of foreign direct investment (FDI) on private investment with a sample having 49 developing countries in Asia (17 countries) and Africa (32 countries) during the period of 1990-2017. Unlike previous studies, we split the data into three groups for further analysis, including the Asian, African and the full-panel samples. The results confirm a crowding-in effect which shows that foreign direct investment promotes private investment on all three research samples. Besides, the lagged private investment has a positive and significant effect on itself in the next period which reflects the inertia in the trend of private investment in recipient countries. In the full-panel sample, there are some macro factors such as GDP per capita, trade openness, and electricity that also have a positive and statistically significant impact on private investment. Besides, when more deeply estimate with smaller samples, we find that trade openness and labour force have a positive and significant in Africa, on the other hand, not in Asia. However, the domestic credit variable has a negative and significant effect on private investment only in Asian developing countries. Furthermore, there is only a positive and significant impact of the electricity variable on private investment in Asia.

• Journal of Information Technology Applications and Management
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• 제19권4호
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• pp.171-184
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• 2012

We suggest that cultural differences among nations should have a significant impact upon the exports of Korean broadcasting contents due to the fact that production and consumption of the contents are influenced by their own cultural aspects. Based on Hofstede's cultural dimensions frequently cited in the literature, we perform empirical analysis to identify the impact of cultural dimensions upon the export amounts by investigating four-year export data of Korean broadcasting industry. In our research model, Hofstede's cultural dimensions and GDP per capita are independent variables and a genre of broadcasting contents is used as a moderating variable. We find in our analysis that three cultural dimensions such as individualism, uncertainty avoidance, masculinity significantly affect the export amount but do not find the impact of power distance.

• 대한안전경영과학회지
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• 제25권4호
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• pp.1-13
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• 2023

This study aims to investigate the correlation between the causes of natural disasters and feng shui factors targeting disaster management experts, feng shui experts, and the general public who are interested in feng shui. To this end, it is intended to reveal that the factors of the disaster at Mt. The purpose of this study is to analyze the impact of three factors on disasters: feng shui factors, natural factors, and social factors. To this end, a survey was conducted targeting feng shui experts, disaster management experts, master's and doctoral students in feng shui geography, residents of the Umyeonsan disaster area, and people interested in feng shui geography. 260 copies of the questionnaire were prepared and 248 copies were used for the final analysis. First, in order to analyze the impact of feng shui factors on awareness of disaster occurrence, after controlling for demographic variables, hierarchical multiple regression analysis was conducted to analyze the impact of feng shui factors on awareness of disaster occurrence. Second, as a result of analyzing the effect of natural factors on awareness of disaster occurrence, looking at each independent variable in the second-stage regression analysis. Third, as a result of analyzing the effect of social factors on awareness of disaster occurrence, looking at each independent variable in the second-stage regression analysis. Finally, as a result of the T-test and Anova analysis conducted for discriminant analysis, if the p-value was less than .005, the F value for each group was obtained as a result of the ANOVA analysis on the feng-shui factors

• 상하수도학회지
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• 제23권3호
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• pp.315-320
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• 2009

This study found that introduction of environmental systems and increased environmental investment have a major impact on K company's sustainable development. The analysis indicated that the environmental investment variable has a close relationship with production quantity, sales, and the amount of sludge treatment variables in K company. However, all other variables including the cost of disinfection chemicals, and the expenditure of sludge treatment have no relationship with the environmental investment variable. Additionally, short-term results show that the company's environmental expenditure variable is conversely related with the environmental performance variable.

• 도시과학
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• 제10권1호
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• pp.21-28
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• 2021

The purpose of this study is to examine the factors affecting the housing satisfaction of elderly households in comparison with non-elderly households, and to present policy implications in terms of housing welfare policies. For this purpose, this study used ordered logit model analysis using '2019 Housing survey data'. As a result of the analysis, in the case of individual/housing characteristics, the analysis results of the non-elderly household model and the elderly household model were similar. However, in the case of regional characteristics, non-elderly households living in the metropolitan area showed higher housing satisfaction than non-elderly households living in the non-metropolitan area, whereas the elderly households living in the metropolitan area had lower housing satisfaction than the elderly households living in the non-metropolitan area. In addition, the satisfaction variable of neighborhood/environmental characteristics that had the greatest impact on the housing satisfaction of non-elderly households was found to be crime prevention status satisfaction, and the satisfaction variable of neighborhood/environmental characteristics that had the greatest impact on the housing satisfaction of elderly households was air pollution satisfaction. The results of the analysis can be used as various reference materials when establishing housing welfare policies for elderly households.

• 유통과학연구
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• 제14권11호
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• pp.129-138
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• 2016

Purpose - The ICT(information and communications technologies) development is affecting consumer behaviors on selecting channel or distribution system. This study aims to advance our knowledge about the factors influencing omni-channel behaviors. This study considers the positive brand experience as the moderating variable into the relationship between omini-channel use intention and consumer brand relation. Also, the effect of positive brand experience on consumer-brand relation is researched. Research design, data, and methodology - This study conducted an empirical test with the subject as customers who purchase goods or service through on-off cross channel simultaneously. The research model is developed from prior literatures about influencing variables on channel selection. The structure of this study is designed to identify causal relationships between the variables. 268 survey data from the questionnaire survey which is conducted to target customers who use online and offline channels, is used for empirical analysis. This study validates generality with descriptive statistics and data reliability with Cronbach's alpha value. The exploratory factor analysis is used for value purification. Then, the confirmatory factor analysis is conducted for structural equation modeling. Finally, the execute structural equation modeling is analyzed to confirm the hypotheses Results - First, the two causal influences between perceived performance risk and the propensity of omni-channel and between price consciousness and the propensity of omni-channel are verified through the empirical test. Second, the result identifies that the propensity of omni-channel is influenced on consumer-brand relationship. Third, the AMOS analysis proves that the moderating variable, positive brand experience, has significant positive impact on consumer-brand relationship. This significant relationship is highly supported by the regression analysis between brand experience and propensity of omni-channel because it results that positive brand experience has positive impact on the propensity of omni-channel. All hypotheses are verified to be true. Conclusions - Based on the empirical result, this study confirms that perceived performance risk and price consciousness are the important factors influencing propensity of omni-channel. According to the additional analysis, the moderating variable and positive brand experience plays important role between the propensity of omni-channel and consumer-brand relationship. Furthermore, positive brand experience influences more on consumer-brand relationship than non-positive brand experience.

• 품질경영학회지
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• 제52권2호
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• pp.185-199
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• 2024

Purpose: The improvement of yield and quality in product manufacturing is crucial from the perspective of process management. Controlling key variables within the process is essential for enhancing the quality of the produced items. In this study, we aim to identify key variables influencing product defects and facilitate quality enhancement in CNC machining process using SHAP(SHapley Additive exPlanations) Methods: Firstly, we conduct model training using boosting algorithm-based models such as AdaBoost, GBM, XGBoost, LightGBM, and CatBoost. The CNC machining process data is divided into training data and test data at a ratio 9:1 for model training and test experiments. Subsequently, we select a model with excellent Accuracy and F1-score performance and apply SHAP to extract variables influencing defects in the CNC machining process. Results: By comparing the performances of different models, the selected CatBoost model demonstrated an Accuracy of 97% and an F1-score of 95%. Using Shapley Value, we extract key variables that positively of negatively impact the dependent variable(good/defective product). We identify variables with relatively low importance, suggesting variables that should be prioritized for management. Conclusion: The extraction of key variables using SHAP provides explanatory power distinct from traditional machine learning techniques. This study holds significance in identifying key variables that should be prioritized for management in CNC machining process. It is expected to contribute to enhancing the production quality of the CNC machining process.

• 한국정보시스템학회지:정보시스템연구
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• 제22권4호
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• pp.49-69
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• 2013

Recently, enterprises have reinforced security control in order to prevent infringement of personal information and abuse of customer information by insiders. However, the reinforcement of security control by enterprises makes it difficult for internal users to perform business by using a business information system. There is, therefore, a need for research on various fields, which makes it possible to establish an appropriate security control policy while minimizing an impact on business. The present research verifies and analyzes an impact on difficulty in business of internal users using customer information, which is caused by security control performed by display restriction on customer information identifiers. The present research is intended to academically develop a technique for statistically analyzing an impact degree and a causal relationship between security control and an impact on business, which is a dichotomous variable, and to practically contribute to the establishment of an efficient security policy in consideration of an impact on business when an enterprise applies security control. A research target was internal business information systems of domestic securities enterprises, data was collected by questionnaire, and verification/analysis was performed by logistic regression analysis.