• 품질경영학회지
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• 제39권3호
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• pp.422-431
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• 2011

The number of mobile telecommunication service subscribers has been over 50 millions as of the end of Nov. 2010. And the number of used mobile phones has been growing continuously caused by shortened life cycle of products and competing between service providers, which is about 21 millions for only one year, 2010 in Korea. However, the quality level of reverse logistics network for used mobile phones is very low and statistics show that the collection ratio of them has not been over 40%. The current low collection ratio can be one of the significant causes of environment destruction due to the cumulated growth. Accordingly new practical alternative recovery systems are required in addition to the current one with EPR(Extended Producers Responsibility). In this paper, suggested are alternative policies to improve the quality level of reverse logistics network for used mobile phones effectively. ENR(Extended Network service providers Responsibility) is representative of them.

• 경영과학
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• 제17권3호
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• pp.19-30
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• 2000

Customization and personalization services are considered as a critical success factor to be a successful Internet store or web service provider. As a representative personalization technique, personalized recommendation techniques are studied and commercialized to suggest products or services to a customer of Internet storefronts based on demographics of the customer or based on an analysis of the past purchasing behavior of the customer. The underlining theories of recommendation techniques are statistics, data mining, artificial intelligence, and/or rule-based matching. In the rule-based approach for personalized recommendation, marketing rules for personalization are usually collected from marketing experts and are used to inference with customers data. however, it is difficult to extract marketing rules from marketing experts, and also difficult to validate and to maintain the constructed knowledge base. In this paper, we proposed a marketing rule extraction technique for personalized recommendation on Internet storefronts using market basket analysis technique, a well-known data mining technique. Using marketing basket analysis technique, marketing rules for cross sales are extracted, and are used to provide personalized advertisement selection when a customer visits in an Internet store. An experiment has been performed to evaluate the effectiveness of proposed approach comparing with preference scoring approach and random selection.

• 대한교통학회지
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• 제29권6호
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• pp.39-56
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• 2011

본 연구에서는 서울시 자치구(행정구역) 중심의 거시적 사고예측모형을 개발하였다. 사고예측모형 개발과정에서 서울시 전체를 하나의 모형식으로 개발하지 않고 지역 토지이용(개발밀도)과 교통사고빈도와의 관계를 분석하여 토지이용 유형에 따른 사고예측모형을 개발하였다. 토지이용과 교통사고빈도와의 관계에서 개발밀도(연상면적)가 높을수록 교통사고빈도가 높게 나타나는 상관성을 파악하였으며 주거연상면적, 상업연상면적, 업무연상면적 모두 교통사고와 반응하는 특징이 다름을 확인할 수 있었다. 총 4개의 유형구분이 가능하였으며 각 유형에 대한 지역특성과 사고특성을 살펴보았다. 4개 유형의 모형에 반영된 설명변수는 공통변수와 각 유형별로 상이한 특성변수가 도출되어 지역적 특성이 모형에 반영된 것으로 판단할 수 있다. 사회 경제적 변수로는 통행을 유발 유입시키는 교통활동을 대변할 수 있는 변수가 채택되었으며 교통여건 변수로는 교통시설 및 안전과 관련된 변수가 채택되었다.

• Smart Structures and Systems
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• 제14권5호
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• pp.917-942
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• 2014

Multivariate statistics based damage detection algorithms employed in conjunction with novel sensing technologies are attracting more attention for long term Structural Health Monitoring of civil infrastructure. In this study, two practical data driven methods are investigated utilizing strain data captured from a 4-span bridge model by Fiber Bragg Grating (FBG) sensors as part of a bridge health monitoring study. The most common and critical bridge damage scenarios were simulated on the representative bridge model equipped with FBG sensors. A high speed FBG interrogator system is developed by the authors to collect the strain responses under moving vehicle loads using FBG sensors. Two data driven methods, Moving Principal Component Analysis (MPCA) and Moving Cross Correlation Analysis (MCCA), are coded and implemented to handle and process the large amount of data. The efficiency of the SHM system with FBG sensors, MPCA and MCCA methods for detecting and localizing damage is explored with several experiments. Based on the findings presented in this paper, the MPCA and MCCA coupled with FBG sensors can be deemed to deliver promising results to detect both local and global damage implemented on the bridge structure.

• 한국보건간호학회지
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• 제31권2호
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• pp.209-219
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• 2017

Purpose: The purpose of this study was to identify the gender differences in the cognitive function and nutritional status among elderly people living in the community. Methods: This study used data from the 2014 National Survey on the Elderly and focused on 10,054 respondents who answered that they did not have dementia. The Korean version of Mini-Mental State Examination for Dementia Screening and the Nutrition Screening Initiative were used. IBM SPSS Statistics 23.0 was used to conduct statistical analyses. Results: The cognitive function score was 25.30 for men, which was higher than for women. The percentage of subjects who showed cognitive decline was 25.5% for males and 50.2% for females, which was statistically significant (p<.001). There were statistically significant differences in the nutritional status between males and females (p<.001). There was a statistically significant negative correlation between the cognitive function and nutritional status in both men and women (p<.001, p<.001). Conclusion: These results showed that the intervention to maintain cognitive functioning should be provided to elderly women with a low education level or high number of chronic diseases and medication, and an intervention to prevent the cognitive decline of the elderly should include nutritional management for health and function maintenance.

• 한국주거학회논문집
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• 제23권5호
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• pp.103-111
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• 2012

This study empirically investigates the degree of physical exclusiveness of multi-family housing estates and its socioeconomic effects. By combining various physical elements devised to blockade and control the entrance to the estate as well as housing units, it constructs the index to quantify the degree of physical exclusiveness for the multi-family housing estates of more than 300 households in Seoul. The statistics reveal that the degree of physical exclusiveness has increased over time and therefore, as a representative example, two-thirds of the estates are now equipped with barricade at the entrance, which often symbolizes 'gated community'. The estimation result of hedonic price model show that physical exclusiveness has a significant positive effect on housing price. The household survey data for the case study estates also demonstrate that the residents in the estate of higher degree of physical exclusiveness put a higher housing value on socioeconomic 'prestige' as well as 'community', beyond physical 'security', and have closer neighborhood relationship with the residents inside the estate. However, there is no significant difference in neighborhood relationship with the outside residents depending upon the degree of physical exclusiveness.

• 보건교육건강증진학회지
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• 제28권1호
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• pp.69-80
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• 2011

Objectives: This study aims to identify the factors associated with colorectal cancer screening behaviors. Methods: The nation-wide representative samples of 2,928 adults aged ${\geq}50$ years for colorectal cancer screening were derived from the fourth Korea National Health and Nutrition Examination Survey (KNHANES IV). This study investigated socio-demographic, health behavioral and contextual factors associated with colorectal cancer screening using descriptive statistics and multivariate logistic regression analysis. Results: In terms of socio-demographic factors, gender, age, marital status, occupation, monthly income, and resident region were significantly different between screening group and non-screening group. Among health behavioral and contextual factors, regular physical checkup, weight control, physical activity, smoking, drinking and having other cancers were significantly different. From the multivariate logistic regression analysis, marital status, education level, regular physical checkup and weight control were associated with colorectal cancer screening behavior. Conclusions: It is necessary to understand the importance of early detection and cancer screening. Appropriate health education and active promotion about the cancer screening should be developed based on the study findings in order to motivate people to have cancer screening. Also, these findings should be reflected in the health policy.

• Communications for Statistical Applications and Methods
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• 제18권1호
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• pp.89-102
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• 2011

이산화는 데이터 마이닝을 위한 전처리 과정으로서 연속형 변수를 이산형 변수로 바꾸는 과정이고, 이산화 시킨 데이터가 원래 가지고 있던 정보손실을 최소로 하면서 높은 분류정확도를 가지는 것을 목적으로 한다. 지금까지 많은 이산화 알고리즘이 제안되었는데, 본 논문에서는 분할 이산화와 병합 이산화의 관점에서 최근까지 제안된 대표적인 이산화 알고리즘들을 비교하고, 이산화 알고리즘이 가지고 있는 특성을 연구하였다. 또한 비교 연구한 이산화 알고리즘을 R코드로 작성하여 다른 연구에 사용할 수 있도록 하였다.

• 성인간호학회지
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• 제26권2호
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• pp.139-148
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• 2014

Purpose: This study was aimed to investigate the factors influencing problem drinking of male drinkers above 19 years old according to the life cycle. Methods: The study subjects consisted of a representative community sample of 2,229 male drinkers aged 19 and older from the 2011 Korean National Health and Nutrition Examination Survey. The collected data were analyzed using descriptive statistics, Rao-Scott $x^2$-test, simple and multiple logistic regressions. Results: The problem drinking rates were 38.7% in adolescence, 44.5% in middle age, and 23.9% in senescence. In adolescence, the predictors of problem drinking included occupation, stress recognition, and smoking. In middle age, the predictors of problem drinking were education level, depression, and smoking. In senescence, the predictors of problem drinking were not identified in this study. Conclusion: The findings of this study suggested that the factors influencing problem drinking of male drinkers were different according to life cycle. Thus different intervention methods should be developed for each age group in order to intervene the problem drinking.

• 한국대기환경학회지
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• 제22권4호
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• pp.421-430
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• 2006

This paper explores a new methodology of socio-statistical survey to classify environmental perception characteristics and to quantify atmospheric environmental sensitivity of neighboring people around a large industrial complex. In order to compensate intrinsic inclination against environmental problems, Atmospheric Environmental Sensitivity Index (AESI) is proposed as the weighted-summation of four representative questions asking the current status of the local air quality, which are chosen by the factor analysis of questionnaire. Atmospheric environmental perception is tried to be classified into interest/indifference characteristics and rational/emotional perception on environmental issues, positive/negative opinion on the solution of environmental problems. According to the chi-square cross-correlation and two-way layout analyses, it was clearly shown that environmental perception is categorized into two major groups, i.e., the positive-rational group having lower AESI and the negative-emotional group having higher AESI which means more seriously senses the status of local air quality.