• 대한지역사회영양학회지
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• 제8권6호
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• pp.910-918
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• 2003

The purposes of this study were to develop a model for university foodservices and to provide management strategies for reducing costs, and increasing productivity and customer satisfaction. The results of this study were as follows : 1) The demands in university food services varied depending on the time series. A fixed pattern was discovered for specific times of the month and semesters. The demand tended to constantly decrease from the beginning of a specific semester to the end, from March to June and from September to December. Moreover, the demand was higher during the first semester than the second semester, within school term than during vacation periods, and during the summer vacation than the winter. 2) Pearson's simple correlation was done between actual customer demand and the factors relating to forecasting the demand. There was a high level of correlation between the actual demand and the demand that had occurred in the previous weeks. 3) By applying the stepwise multiple linear regression analysis to two different university food services providing multiple menu items, a model was developed in terms of four different time series(first semester, second semester, summer vacation, and winter vacation). Customer preference for specific menu items was found to be the most important factor to be considered in forecasting the demand.

• 산업경영시스템학회지
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• 제38권2호
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• pp.40-46
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• 2015

The modular assembly system can make it possible for the variety of products to be assembled in a short lead time. In this system, necessary components are assembled to optional components tailor to customers' orders. Budget for inventory investments composed of inventory and purchasing costs are practically limited and the purchasing cost is often paid when an order is arrived. Service cost is assumed to be proportional to service level and it is included in budget constraint. We develop a heuristic procedure to find a good solution for a continuous review inventory system of the modular assembly system with a budget constraint. A regression analysis using a quadratic function based on the exponential function is applied to the cumulative density function of a normal distribution. With the regression result, an efficient heuristics is proposed by using an approximation for some complex functions that are composed of exponential functions only. A simple problem is introduced to illustrate the proposed heuristics.

• 한국전자통신학회논문지
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• 제14권4호
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• pp.775-780
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• 2019

미래를 예측하는 기법은 통계에 기반을 둔 것과 딥러닝에 기반을 둔 기술로 분류할 수 있다. 그중 통계에 기반을 둔 것이 간단하고 정확성이 높아서 많이 사용된다. 하지만 실무자들은 많은 분석기법의 올바른 사용에 어려움이 많다. 이번 연구에서는 마케팅에 관련된 데이터에 다항로지스틱회귀, 의사결정나무, 랜덤포레스트, 서포트벡터머신, 베이지안 추론을 적용하여 예측의 정확성을 비교하였다. 동일한 마케팅 데이터를 대상으로 하였고, R을 활용하여 분석을 진행하였다. 마케팅 분야의 데이터 특성을 반영한 다양한 기법의 예측 결과가 실무자들에게 좋은 참고가 될 것으로 생각한다.

• 동아시아경상학회지
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• 제10권2호
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• pp.19-30
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• 2022

Purpose - The research aims to explore the ability of the combination of the Technology Acceptance Model (TAM) and Theory of Reasoned Action (TRA) to predict and explain the online shopping intention of Vietnamese consumers. The findings of this study provide empirical results to assess the factors influencing behavioural intention in the E-commerce field. Research design, data, and methodology - The research approach of this study is quantitative. The data was collected from 214 respondents on e-commerce platforms. The collected data will then be analyzed to test the proposed hypothesis in this study. Multiple Regression Analysis and Simple Linear Regression are employed to test the hypothesis. Result - Perceived benefits, Perceived risk reduction, and trust positively influence Attitude toward using Ecommerce. There is a positive relationship between Subjective norms and Behavioural intention to shop online. There is a positive relationship between Attitude toward using E-commerce and Behavioural intention to shop online. Conclusion - This study is based on the Theory of Reasoned Action (TRA) model and the Technology Acceptance Model (TAM) to explore the factors influencing the online shopping intention of Vietnamese consumers. Besides, this paper contributes to the managerial implications for E-commerce managers and policymakers to promote E-commerce among Vietnamese consumers.

• Geomechanics and Engineering
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• 제37권3호
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• pp.197-211
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• 2024

This research studies the effect of geotechnical factors on EPB-TBM performance parameters. The modeling was performed using simple and multivariate linear regression methods, artificial neural networks (ANNs), and Sugeno fuzzy logic (SFL) algorithm. In ANN, 80% of the data were randomly allocated to training and 20% to network testing. Meanwhile, in the SFL algorithm, 75% of the data were used for training and 25% for testing. The coefficient of determination (R²) obtained between the observed and estimated values in this model for the thrust force and cutterhead torque was 0.19 and 0.52, respectively. The results showed that the SFL outperformed the other models in predicting the target parameters. In this method, the R² obtained between observed and predicted values for thrust force and cutterhead torque is 0.73 and 0.63, respectively. The sensitivity analysis results show that the internal friction angle (φ) and standard penetration number (SPT) have the greatest impact on thrust force. Also, earth pressure and overburden thickness have the highest effect on cutterhead torque.

• Journal of Chest Surgery
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• 제27권10호
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• pp.833-837
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• 1994

Lung contusion due to blunt chest trauma is the most common lung injury and correlated with the clinical course and prognosis. Its diagnosis by CT[Computerized Tomogram] gives a more clear and understandable three dimensional view, by which we are able to measure the volume of the contused and entire lung. Other variables are arterial blood gas, number of rib fracture, presence of hemopneumothorax, sternal fracture and clavicle fracture, number of associated non-thoracic injuries, ventilator time and presence of pulmonary complication. Percentage[%] of lung contusion are expressed as mean $\pm$ standard deviation and data analysis was performed by means of multivariate repeated measures analysis of variance to detect significant differences in variables between positive thoracic injury group and negative group. The paired t-test was used. Differences of percentage of lung contusion between groups were assessed by one-way analysis of variance. Simple linear regression was used to perform correlation analysis in the number of rib fracture and ventilator time. A p value less than 0.05 was considered statistically significant. Pneumothorax and the number of associated other injuries affect the amount of lung contusion and pulmonary complication group has more contused lung volume. Arterial blood gas study shows no correlation with the amount of lung contusion statistically. The number of rib fracture correlated with the amount of lung contusion, which also correlated with ventilator time[r=0.56, p<0.05]. In conclusion, quantitative anlysis of lung contusion by CT predicts the clinical course and treatment such as ventilator care.

• 한국의상디자인학회지
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• 제22권3호
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• pp.89-98
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• 2020

The survey targeted 270 men and women in their from their 20s-50s who live in Seoul and Gyeonggi-do. The purpose of this study was to investigate the effect of the vocation of beauty worker on job satisfaction and self-development. The questionnaire was administered from January 5th to March 10th, 2020, and 243 responses were used for statistical analysis. 27 unanswered or unfaithful questionnaires were disregarded. Using SPSS WIN 21.0 was applied for statistical processing. First, the data was analyzed using descriptive statistical analysis, factor analysis, and reliability verification, For validity verification, one-way variance analysis, correlation analysis, and simple regression analysis were used. The results of this study are as follows. First, upon examining the hypothesis that vocation has a positive (+) effect on job satisfaction, a significant positive (+) influence was shown, and it was found that it was determined vocation is an important factor in job satisfaction for beauty industry professionals. Second, upon examining the hypothesis that vocation has a positive (+) effect on self- development, a significant positive (+) correlation was found between the self-development of beauty industry professionals and job satisfaction. Third, upon examining the hypothesis that occupational vocation has a positive (+) effect on self- development, a significant positive (+) correlation was shown between self-development and job satisfaction of beauty industry professionals.

• 한국조리학회지
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• 제23권2호
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• pp.74-85
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• 2017

This study conducted to analyze the causal relationships among image factors (brand, store, enterprise) of family restaurants, customer satisfaction, customer trust, and revisit intention as perceived by 271 customers, who have visited a family restaurant located in Ulsan and Busan regions. Present study performed frequency analysis, factor analysis, customer trust analysis, correlation analysis, and multiple (simple) regression analysis using SPSS 18.0 statistical program. The analysis results indicated that the image of family restaurants had significant positive (+) influences on customer satisfaction, customer trust, and revisit intention, among which the biggest influential factor was found to be the store factor. Significant influence was shown for brand image followed by corporate image. In addition, customer satisfaction and customer trust had significant positive (+) influences on revisit intention. As a result of this study, store image among family restaurant images appeared as the most important element; hereupon, this study considers that it is necessary for a family restaurant to build a differentiated image to increase revisit intention by satisfying customer needs and by encouraging customers to have trust in the restaurant.

• KIEAE Journal
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• 제12권6호
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• pp.93-98
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• 2012

The concerns on high ozone concentration phenomenon is significantly growing in Seoul metropolitan area including the industry complex area, like Shiwha Banwol area. The aims of this research is the analysis of relationship between high concentrations of $O_3$ and solar radiation parameters in atmosphere. The understanding of the effects of solar radiation intensity, humidity, high air temperature on ozone concentration in a day is very useful to provide a direction for reducing of the high ozone concentration to a local government or a metropolitan government. The correlation analysis between maximum ozone concentration and various meteorological parameters in 2009 - 2011 carried out using IBM's SPSS program. The results showed that the mean correlations coefficient (R) between daily Ozone maximum and solar radiation resulted R = 0.64 during 2011. May - September in 10 air pollution stations. In case of correlations between daily ozone maximum and relative humidity showed negative correlation R = -0.61. The correlation analysis with mean air temperature during 1-3 PM resulted R = 0.29. This low correlation coefficient could be corrected by using of categorized data of ozone concentration. The daily maximum ozone concentration is more dependent on peak solar radiation and high air temperature during 1-3 PM than its simple daily maximum values. The results of this research would be used to develop the high ozone alert system around Seoul metropolitan area. This correlation analysis could be partially integrated to prediction of ozone peak concentration in connection with other methods like classification and regression tree(CART).

• Journal of Preventive Medicine and Public Health
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• 제31권3호
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• pp.384-394
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• 1998

In order to investigate the effect of the urinary excretion of sodium and potassium on the change on blood pressure over 3 years, 668 adolescents aged 13 years living in Kangwha area were investigated in a longitudinal follow-up study. Two measurements were taken on each blood pressure (diastolic, systolic) and the average of the two readings was used in the analysis. Sodium and potassium intake were estimated by the determination of those electrolytes in 24hr urine. The mixed model regression analysis was used to identify the effect of urinary sodium and potassium on the change of blood pressure after controlling for BMI of each age. On simple bivariate analysis no relationship was found between urinary sodium excretion and systolic or diastolic blood pressure among both male and female, however, a significant positive association between urinary potassium excretion and systolic blood pressure among male. The results of mixed regression analysis showed that the body mass index (BMI) were more influential that urinary electrolytes among this study subjects. It suggested that risk factors observed from the adults, may not be identical with that of the growing aged population. After control of the BMI and age, significant association between sodium and diastolic BP among male, and association between potassium and systolic BP among female, were found. In summary, the results indicate that growth has been more influential than dietary factor on blood pressure for growing aged population.