• Journal of the Korea Society of Computer and Information
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• v.18 no.3
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• pp.35-45
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• 2013

MANET has a weak point because it allows access from not only legal nodes but also illegal nodes. Most of the MANET researches had been focused on attack on routing path or packet forwarding. Nevertheless, there are insuffcient studies on a comprehensive approach to detect various attacks on malicious nodes at packet forwarding processes. In this paper, we propose a technique, named DTecBC (detection technique of malicious node behaviors based on collaboration), which can handle more effciently various types of malicious node attacks on MANET environment. The DTecBC is designed to detect malicious nodes by communication between neighboring nodes, and manage malicious nodes using a maintain table. OPNET tool was used to compare with Watchdog, CONFIDANT, SRRPPnT for verifying effectiveness of our approach. As a result, DTecBC detects various behaviors of malicious nodes more effectively than other techniques.

• Journal of Korean Society of Forest Science
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• v.90 no.5
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• pp.643-649
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• 2001

The case study of the Cooperatives' members and Sincere Forest Managers/Forest Successors was carried out to find the determinants affecting the forest investment of private forest owners and analyze their effects on it. For this the landowners' forest investment probability function was estimated using the logistical regression model. The results showed that the forest investment of the Cooperatives' members was the function of forest area, stand age, forest income, and technical assistance. Three of the variables (forest income, forest area, and technical assistance) exhibited a positive effect on the forest investment as expected, while stand age showed a negative effect unlike the expectation of the study. In case of Sincere Forest Managers and Forest Successors forest area, distance(1)(distance from forest to road accessible by vehicle), knowledge of financing program, and forest income were significant indicators for the forest investment. All these variables showed the expected signs; forest area, knowledge of financing, and forest income had a positive effect on the forest investment, and distance(1) showed a negative effect.

• Design Convergence Study
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• v.16 no.2
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• pp.63-81
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• 2017

Environmental change of consuming contents has led corporates to acknowledge the possibility of social media as being marketing platform. And as the importance of 'contents' is growing bigger at the same time, 'Content Marketing' is getting attention because 'Content' plays the key role in current marketing since it can deliver meaningful values to the companies and the customers both. Many companies are practicing contents marketing employing YouTube by not only creating their own YouTube channels and YouTube contents but also collaborating with YouTube creators. Purpose of this study is to figure out how domestic standalone beauty brands that are actively practicing content marketing, are exploiting the YouTube and to suggest design direction for future YouTube content marketing. 'Etude', 'Innisfree', 'Misha', 'The Face Shop' were selected for analyzing the content marketing cases using YouTube. As a result, this study could conclude that if the brand has inadequate number of subscribers, it is better to collaborate with the creators. Also, clarifying contents' purpose and distinguishing the way of delivering it is important.

• The Journal of the Convergence on Culture Technology
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• v.9 no.4
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• pp.13-22
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• 2023

Recently, global luxury fashion brands such as Gucci, Saint Laurent, and Louis Vuitton have been showing special interest in Korean contemporary artists and actively collaborating with them. This can be said to be a new change that is distinguished from previous collaborations of fashion brands. Therefore, this study investigated the cases of collaboration between global luxury fashion brands and Korean contemporary artists, and analyzed the types and characteristics to examine the trends and characteristics and draw meaning. As a result, fashion brands combine the characteristics of Korean art works of various genres with the brand concept and pursued values to create new sensibility and high value-added products. It can be seen that the intention was to prepare a place to draw out. In addition, it was found that collaboration was also utilized in terms of marketing so that domestic customers could visit the brand store with a sense of familiarity by utilizing Korea's artistic and cultural sentiments. Based on the results of this study, we intend to provide basic data for the development of creative contents for various collaborations between fashion and art that can help develop the modern fashion industry.

• Journal of Intelligence and Information Systems
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• v.15 no.4
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• pp.183-200
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• 2009

Collaborative Filtering is one of the most used recommender systems. However, basically it cannot be used to recommend new products to customers because it finds products only based on the purchasing history of each customer. In order to cope with this shortcoming, many researchers have proposed the hybrid recommender system, which is a combination of collaborative filtering and content-based filtering. Content-based filtering recommends the products whose attributes are similar to those of the products that the target customers prefer. However, the hybrid method is used only for the limited categories of products such as music and movie, which are the products whose attributes are easily extracted. Therefore it is essential to find a more effective approach to recommend to customers new products in any category. In this study, we propose a new recommendation method which applies centrality concept widely used to analyze the relational and structural characteristics in social network analysis. The new products are recommended to the customers who are highly likely to buy the products, based on the analysis of the relationships among products by using centrality. The recommendation process consists of following four steps; purchase similarity analysis, product network construction, centrality analysis, and new product recommendation. In order to evaluate the performance of this proposed method, sales data from H department store, one of the well.known department stores in Korea, is used.

• Journal of Christian Education in Korea
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• v.70
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• pp.11-35
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• 2022

The purpose of this article is to suggest nine types of educational ministry based on the practical theology in Christian Education. For the purpose this article emphasizes an individual dimension including church, society dimensions. An individual dimension is based on the spirit of post digital era within sociocultural area in different with personal-existential area of the philosophical and theological perspective and life cycle theology area of the developmental psychological perspective. Post digital era means the humanization of digital, digital friendly, and emotional digital cultural characteristics. Post digital generation means child, youth, young adults those who are accustomed with post digital cultural of the post digital era. The educational ministry for the post digital generations categorized into nine types according to correlation with individual, church, and society as a field of ministry and critical scientific method, critical confessional method, and critical correlational method as an interdisciplinary which are composed of Christian tradition and contemporary science. Representative key competencies of nine types in the educational ministry are media literacy, relational identity, communication, high touch, discipleship, making and using media, integrative vocation, collaboration abilities, and home, school, and social resilience in relation with multicultural generations.

• Journal of Intelligence and Information Systems
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• v.24 no.2
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• pp.85-109
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• 2018

Recommender system recommends the items expected to be purchased by a customer in the future according to his or her previous purchase behaviors. It has been served as a tool for realizing one-to-one personalization for an e-commerce service company. Traditional recommender systems, especially the recommender systems based on collaborative filtering (CF), which is the most popular recommendation algorithm in both academy and industry, are designed to generate the items list for recommendation by using 'overall rating' - a single criterion. However, it has critical limitations in understanding the customers' preferences in detail. Recently, to mitigate these limitations, some leading e-commerce companies have begun to get feedback from their customers in a form of 'multicritera ratings'. Multicriteria ratings enable the companies to understand their customers' preferences from the multidimensional viewpoints. Moreover, it is easy to handle and analyze the multidimensional ratings because they are quantitative. But, the recommendation using multicritera ratings also has limitation that it may omit detail information on a user's preference because it only considers three-to-five predetermined criteria in most cases. Under this background, this study proposes a novel hybrid recommendation system, which selectively uses the results from 'traditional CF' and 'CF using multicriteria ratings'. Our proposed system is based on the premise that some people have holistic preference scheme, whereas others have composite preference scheme. Thus, our system is designed to use traditional CF using overall rating for the users with holistic preference, and to use CF using multicriteria ratings for the users with composite preference. To validate the usefulness of the proposed system, we applied it to a real-world dataset regarding the recommendation for POI (point-of-interests). Providing personalized POI recommendation is getting more attentions as the popularity of the location-based services such as Yelp and Foursquare increases. The dataset was collected from university students via a Web-based online survey system. Using the survey system, we collected the overall ratings as well as the ratings for each criterion for 48 POIs that are located near K university in Seoul, South Korea. The criteria include 'food or taste', 'price' and 'service or mood'. As a result, we obtain 2,878 valid ratings from 112 users. Among 48 items, 38 items (80%) are used as training dataset, and the remaining 10 items (20%) are used as validation dataset. To examine the effectiveness of the proposed system (i.e. hybrid selective model), we compared its performance to the performances of two comparison models - the traditional CF and the CF with multicriteria ratings. The performances of recommender systems were evaluated by using two metrics - average MAE(mean absolute error) and precision-in-top-N. Precision-in-top-N represents the percentage of truly high overall ratings among those that the model predicted would be the N most relevant items for each user. The experimental system was developed using Microsoft Visual Basic for Applications (VBA). The experimental results showed that our proposed system (avg. MAE = 0.584) outperformed traditional CF (avg. MAE = 0.591) as well as multicriteria CF (avg. AVE = 0.608). We also found that multicriteria CF showed worse performance compared to traditional CF in our data set, which is contradictory to the results in the most previous studies. This result supports the premise of our study that people have two different types of preference schemes - holistic and composite. Besides MAE, the proposed system outperformed all the comparison models in precision-in-top-3, precision-in-top-5, and precision-in-top-7. The results from the paired samples t-test presented that our proposed system outperformed traditional CF with 10% statistical significance level, and multicriteria CF with 1% statistical significance level from the perspective of average MAE. The proposed system sheds light on how to understand and utilize user's preference schemes in recommender systems domain.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.237-237
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• 2021

2020년의 경우 6월부터 8월 중순까지 54일 동안 전국에 걸쳐 대규모 폭우가 집중적으로 내리면서 산사태·침수·저수지 붕괴 등이 산발적으로 발생하였다. 특히 집중호우와 같은 풍수해의 경우 매년 반복적으로 발생하는 재난유형으로서 안전점검과 같은 대비를 위한 활동을 실시하고 있음에도 피해가 꾸준히 발생하고 있는 실정이다. 재난으로 인한 반복적인 피해로 인해 국가의 재난대응에 관한 관심이 점차 증가하고 있다. 현재 이러한 재난대응을 위하여 재난유형별로 위기관리 매뉴얼을 구축하였으며, 13개 협업기능을 통해 효율적인 재난대응을 실시하고자 정부 및 각 지자체, 유관기관 등이 노력하고 있는 실정이다. 그러나 복합적이고 큰 규모의 재난이 발생하면 현장과 상황실 간에 정보공유가 제대로 이루어지지 않는다는 문제가 반복적으로 발생하고 있다. 재난이 발생하면 지자체에서 재난대응 및 상황관리를 우선적으로 실시하고 있으나 재난현장에 파견한 현장담당자의 경우 잦은 보직이동으로 재난현장에서 필요로 하는 정보와 전달해야하는 필수정보에 대해 정확히 알지 못해 재난현장에서 수집해야할 정보들을 제대로 파악하지 못하는 등 재난대응에 있어 어려움을 겪기도 한다. 또한 현장대응 담당자들이 초기 대응에 집중 할 수 있는 정보전달 체계가 존재하지 않아 상황실에서 재난현장으로 필요로 하는 정보를 전송하는 현장대응 지원체계가 미비한 상황이다. 이에 본 연구에서는 재난현장과 상황실 간 원활한 소통뿐 만 아니라 재난현장담당자들이 재난현장 및 피해현황 정보 등을 신속하게 수집할 수 있도록 재난현장에서 필수적으로 수집되어야하는 정보 DB(Database)를 설계하였으며, 이를 바탕으로 모바일 기반 재난현장 정보수집 앱을 개발하여 현장대응 지원체계의 기초를 제시하고자 하였다.

• Journal of the Korean Society for information Management
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• v.32 no.1
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• pp.23-41
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• 2015

This study worked on the qualitative analysis about nomenclature East Sea by the record type in researches related to East Sea shown in the scientific journals. Here in this study, the way of marking is classified as three: 'sole notation of East Sea', 'sole notation of Sea of Japan', and 'simultaneous notation of both'. Based on a total of 4,192 selections from Web of Science DB, the analysis was followed up for change in time series by the notation type, notation type according to the nation that authors belong to, difference in research topic, impact factor, collaboration in research, and co-authorship network. The result turned out in this work that the sole notation of Sea of Japan accounted for the largest portion. It also showed that the rates of sole notation of East Sea and simultaneous notation have kept increasing continuously since the 1990s. Hub nations regarding the research of East Sea is five including Japan, Russia, Korea, USA, and China. In the case of sole notation of Sea of Japan, active collaboration studies are performed in USA, Russia, and China with a focus in Japan. In the case of sole notation of East Sea and simultaneous use, the research rate is relatively high in USA and Japan with a focus in Korea. As to the co-authorship network in the sole notation of Sea of Japan, sort of a "giant component" among different groups has been set up and through which the collaborative works are actively underway. However, it was found that the research of sole notation of East Sea is dispersed into small groups on the base of relevant individual institution.

• Journal of Elementary Mathematics Education in Korea
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• v.22 no.2
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• pp.143-159
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• 2018

Since the mathematics learning achievement level is closely related to problem-solving ability, it is necessary to understand the relationship between problem-solving ability and meta-affect ability from the point of view of general mathematics learning ability. In this study, we compared the frequency analysis and the case analysis of the functional aspects of the meta-affect in elementary school students' problem-solving processes according to mathematics learning achievement level in parallel with frequency analysis and case analysis. In other words, the frequency of occurrence of meta-affect, the frequency of meta-affective type, and the frequency of meta-functional types of meta-affect were compared and analyzed according to the mathematics learning achievement level in the collaborative problem-solving activities of small group members with similar mathematics learning achievement level. In addition, we analyzed the representative cases of meta-affect by meta-functional types according to the mathematics learning achievement level in detail. As a result, meta-affect in problem-solving processes of the upper level group acted as relatively various types of meta-functions compared to the lower level group. And, the lower level group, the more affective factors acted in the problem-solving processes.