• The KIPS Transactions:PartD
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• v.19D no.1
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• pp.1-14
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• 2012

As the size of the data warehouse is large, the selection of indices on the data warehouse affects the efficiency of the query processing of the data warehouse. Indices induce the lower query processing cost, but they occupy the large storage areas and induce the index maintenance cost which are accompanied by database updates. The bitmap join indices are well applied when we optimize the star join queries which join a fact table and many dimension tables and the selection on dimension tables in data warehouses. Though the bitmap join indices with the binary representations induce the lower storage cost, the task to select the indexing attributes among the huge candidate attributes which are generated is difficult. The processes of index selection are to reduce the number of candidate attributes to be indexed and then select the indexing attributes. In this paper on bitmap join index selection problem we reduce the number of candidate attributes by the data mining techniques. Compared to the existing techniques which reduce the number of candidate attributes by the frequencies of attributes we consider the frequencies of attributes and the size of dimension tables and the size of the tuples of the dimension tables and the page size of disk. We use the mining of the frequent itemsets as mining techniques and reduce the great number of candidate attributes. We make the bitmap join indices which have the least costs and the least storage area adapted to storage constraints by using the cost functions applied to the bitmap join indices of the candidate attributes. We compare the existing techniques and ours and analyze them in order to evaluate the efficiencies of ours.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.1
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• pp.61-71
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• 2010

The attributes related to the health condition of RC deck slabs are analyzed to help us identify and rate the safety level of the bridges in this study. According to the related reports the state assessment for the outward aspects of bridges is the important and critical part for rating the overall structural safety. In this respect, the careful identification for the various state attributes make the field inspection and structural diagnosis very effective. This study analyzes the influence of the state attributes on evaluation classes and the relationship of them by the inductive reasoning, which raise the understanding and performance for evaluation work, and support the logical approach for the state assessment. ID3 algorithm applied to the case set which is constructed from the field reports indicates the main attributes and the precedence governing the assessment, and derives the decision hierarchy for the state assessment.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.3
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• pp.29-38
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• 2008

This study intends to analyze the value of school forests, one type of urban forest. For this purpose, four attributes of school forests were investigated, considering ecological, educational, social and economic values using a conjoint model as the stated preference. Based on literature reviews, the levels of the four attributes were selected, and a questionnaire survey was given to 279 urban residents divided into 2 groups: those impacted by school forests and those not. The study results suggest that the most important attribute of school forests is economic value, and next is ecological, social and educational value according to the part-worth model. The fitness level of the model is 0.900(total group) which is very significant. As for the economic value, free and 1,000 won are more critical factors than the other 2 levels, 5,000 won and 10,000 won and air pollution purification and making the school landscape are more critical factors than small habitats and microclimate factors. In addition, regarding the social value related to residents' leisure activities，the utility of nature observation is higher than walking and exercising. Finally, for educational value, understanding nature's importance is more critical than the emotions and learning of students. The estimated WTP per household/month is 3,580 won, the group related to school forestsis 3,650 won and the non-related group is 3,540 won. Based on these results, the estimated total economic value of all households per year is 6,820 hundred million won. The group related to school forests is 6,970 hundred million won and the non-related group is 6,750 hundred million won.

• Culinary science and hospitality research
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• v.23 no.2
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• pp.11-22
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• 2017

This study is focused on five franchise snack bars to create an effective marketing strategy by analyzing the competitive relationships among them and by grasping selection properties that satisfy customers. Discriminant Analysis was utilized to suggest methodological frameworks, and the results show three factors (food quality, employees' service, and physical environment) were extracted that contains twenty five questions. A one-way analysis of variance (ANOVA) was carried out in order to verify if there were statistically meaningful differences in the Franchise snack bars, and post hoc comparisons were conducted using the Duncan method. In addition, Multidimensional Scaling (MDS) was used to measure brand similarity, selection attributes, and brand preferences. The results of the analysis show that Addal had the highest scores on average in all three factors (food quality, employees' service, and physical environment), Bong-Gus Babberger had two higher scored factors (employees' service and physical environment) than the average, and Gobongmin kimbab had also two higher scored factors (food quality and physical environment) than the average. Kimbab chunguk appeared to have lower scores than the average in all three factors (food quality, employees's service, and physical environment). The findings of this study provide a useful positioning map of competitiveness among five brands and offer practical marketing proposals.

• Culinary science and hospitality research
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• v.17 no.4
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• pp.59-73
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• 2011

The purpose of this study is to establish a marketing strategy for the makgeolli manufacturing industry. We fractionized cousumer types depending on motives for purchase of customers who had bought makeolli or drunk it for the last six months. We also examined the relationship between makgeolli selection attributes and customer satisfaction by the cousumer types. SPSS 15.0 statistical package was used to process data. Frequency analysis, factor analysis, a reliability test, K-means cluster analysis, one-way ANOVA, and multiple regression were executed. As a result, the motives to purchase and drink were divided into four factors - marketing, effect on health, self-desires, outside environment; consumers into three types - dependent type, loving type, indifferent type; makgeolli selection attributes into five factors - health characteristics, visual elements, brand characteristics, drinking characteristics, purchase characteristics. It was shown that the makgeolli loving type considered all the makgeolli selection attributes as most important; the dependent type considered the health characteristics and visual elements as less important than the loving type did. The indifferent type considered all the makgeolli selection attributes as less important compared with the other types. Among the makgeolli selection attributes, drinking characteristics and the purchase characteristics had effects on customer satisfaction.

• The Journal of the Korea Contents Association
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• v.19 no.5
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• pp.602-611
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• 2019

The purpose of this study is to provide effective basic data necessary for marketing strategy of HMR products by identifying the effect of HMR selection attributes on customer satisfaction according to family Composition. To this end, the research subjects conducted a survey with employees dispatched to 100 of 140 HOMEPLUS nationwide and surveyed customers who purchased HMR products from stores for about 60 days from July 1, 2018 to August 30, 2018. The data collected were analyzed for statistical significance using SPSS 21.0 for windows, and the hypothesis was verified based on the results processed. Research shows that the four factors, quality, price, convenience and variety, which are the sub-factors of HMR selection attributes, were not different according to family composition, the quality, price, and variety among the sub-factors of HMR selection attributes affected customer satisfaction, but the convenience factors did not affect customer satisfaction. The purpose of this study was to identify the effect of HMR selection attributes on customer satisfaction and to compare the differences according to the general characteristics of survey subjects, The present invention has been made in view of the above problems.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2005.04a
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• pp.293-296
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• 2005

최근 우리나라는 가계신용의 급신장과 신용불량의 급증 등으로 개인 신용부문이 금융기관의 건전성 유지에 부정적인 영향을 미치고 있다. 이러한 잠재적 문제를 사전에 방지하기 위해 금융기관 등에서는 개인 신용평가에 대한 수요가 커지고 있는 실정이다. 주어진 데이터로부터의 반복적인 학습 과정을 거쳐 패턴을 분류하고 또한 모델과 학습 방법에 따라 입력변수와 목적변수의 속성이 연속형이나 이산형인 경우를 모두 다룰 수 있는 신경망 모델은 개개인의 다양하고 복잡한 데이터를 입력변수로 받아서 신용등급을 나누는데 우수한 능력을 보여줄 수 있다. 본 논문에서는 신경망 모델을 이용해 개인의 신용등급을 객관적이고 일률적으로 평가해서 등급을 나누어주는 알고리즘을 제안하고자 한다.

• The KIPS Transactions:PartD
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• v.9D no.6
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• pp.1009-1016
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• 2002

We design and implement a new case-based recommender system using implicit rating information for a digital content site. Our system consists of the User Profile Generation module, the Similarity Evaluation and Recommendation module, and the Personalized Mailing module. In the User Profile Generation Module, we define intra-attribute and inter-attribute weight deriver from own's past interests of a user stored in the access logs to extract individual preferences for a content. A new similarity function is presented in the Similarity Evaluation and Recommendation Module to estimate similarities between new items set and the user profile. The Personalized Mailing Module sends individual recommended mails that are transformed into platform-independent XML document format to users. To verify the efficiency of our system, we have performed experimental comparisons between the proposed model and the collaborative filtering technique by mean absolute error (MAE) and receiver operating characteristic (ROC) values. The results show that the proposed model is more efficient than the traditional collaborative filtering technique.

• Journal of The Korean Association For Science Education
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• v.34 no.2
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• pp.93-105
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• 2014

Group creativity has recently been heightened as a core competence in the 21st century. Therefore, there is a need for introduction of concepts on design thinking emphasizing the collaboration and empathy to science education as an effective method for fostering group creativity. Understanding design thinking for effective introduction should be preceded, so we explore the characterizations of design thinking through the generic model overlay method, focus group interview, and critical incident technique analysis. The results reveal 4 cluster units of competency and 15 core competencies. The collaboration cluster consists of 5 competencies and they are as follows: organization of the team, communication, self-control, persuasiveness, and initiative competency. The integrative thinking cluster consists of 3 competencies and they are as follows: analytical, strategic, and intuitive thinking competency. The human-centeredness cluster consists of 3 competencies and they are as follows: user-orientation, relationship building, and interpersonal understanding competency. The multidisciplinary cluster consists of 4 competencies and they are as follows: achievement orientation, information seeking, curiosity, and flexibility competency. Findings are expected to provide the basic data for developing programs and establishing strategies in order to foster group creativity as well as introducing design thinking to science education effectively.

• Korean Journal of Food Science and Technology
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• v.43 no.6
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• pp.735-741
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• 2011

Bealmijang is a short-term fermented regional product that is prepared with soybean and extra ingredients. In this study, starter strain candidates were screened from Bealmijang for fermented soybean paste products. Twenty one bacterial strains producing extracellular enzymes (amylase, cellulase, protease, xylanase and lipase) were isolated from Bealmijang, buckwheat sokseongjang. The isolates were assessed for fibrinolytic and antibacterial activities, and salt tolerance. Strain HJ18-4, identified as Bacillus subtilis (AB601598) by biochemical properties (89.6%) and 16S rDNA sequencing (100%), showed the highest enzymatic, fibrinolytic, and antibacterial activities among the isolates. Although the growth of HJ18-4 was inhibited by the increase of NaCl concentration, the growth still exceeded that of B. subtilis KACC 10114 at 5% and 10% NaCl. These results suggest that B. subtilis HJ18-4 is suitable as a starter for soybean paste manufacture.