• Journal of the Korean Data and Information Science Society
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• v.25 no.2
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• pp.317-325
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• 2014

Evaluating contents and quality of the journal along with the research ability of researcher is becoming an important issue recently. This research compared level of impact of the journals related to statistics in nation, 'Journal of the Korean Data & Information Science Society'-centric, using various KCI citation index. Moreover, this research surveyed network between the journals in the aspect of social network analysis, using co-citation frequency. From that, the following conclusions were drawn. First, percentage of self-citation was relatively high. Second, even though Statistics journal had higher impact index than the mathematics, physics and chemistry, frequency of citing statistics journal in other journals was not that high. Third, 'Journal of the Korean Data & Information Science Society' serves central role in network analysis, however it seems that more efforts are required.

• Journal of the Korean Regional Science Association
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• v.36 no.4
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• pp.3-23
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• 2020

This study aims to conceptualize the settlement inclusivity for overcoming social exclusion and the decline in quality of life of older people and to examine its effects on their mental health. The concept of the settlement inclusivity for older people focuses on the immediate environment around the place where they live. We proposed two domains for the conceptual framework; social domain that provides opportunities for community cohesion; spatial domain that provides security of residential area and access to basic services within walking distance. The social domain was represented by participation and interdependence, while the spatial domain by security and accessibility in the settlement inclusivity. Zero-inflated negative binomial regression model was constructed with 2017 National Survey of Older Koreans data to analyze the factors influencing depressive symptoms of older adults. The empirical results demonstrate that increased level of neighborhood network and social participation is associated with a decrease in the number of depressive symptoms. In addition, higher satisfaction in neighborhood environment and good accessibility to public transport/stores are associated with fewer depressive symptoms. Finally, housing condition and home ownership have a moderating effect on the relationship between social network/participation and depressive symptoms level, whereas they have no direct effects on depressive symptoms. This study demonstrates multi-dimensionally and mutually significant associations between settlement inclusivity and depressive symptoms for older people providing implications for urban planning and policies to improve mental well-being of older population.

• Journal of Intelligence and Information Systems
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• v.22 no.3
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• pp.113-127
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• 2016

Among the techniques for recommendation, collaborative filtering (CF) is commonly recognized to be the most effective for implementing recommender systems. Until now, CF has been popularly studied and adopted in both academic and real-world applications. The basic idea of CF is to create recommendation results by finding correlations between users of a recommendation system. CF system compares users based on how similar they are, and recommend products to users by using other like-minded people's results of evaluation for each product. Thus, it is very important to compute evaluation similarities among users in CF because the recommendation quality depends on it. Typical CF uses user's explicit numeric ratings of items (i.e. quantitative information) when computing the similarities among users in CF. In other words, user's numeric ratings have been a sole source of user preference information in traditional CF. However, user ratings are unable to fully reflect user's actual preferences from time to time. According to several studies, users may more actively accommodate recommendation of reliable others when purchasing goods. Thus, trust relationship can be regarded as the informative source for identifying user's preference with accuracy. Under this background, we propose a new hybrid recommender system that fuses CF and social network analysis (SNA). The proposed system adopts the recommendation algorithm that additionally reflect the result analyzed by SNA. In detail, our proposed system is based on conventional memory-based CF, but it is designed to use both user's numeric ratings and trust relationship information between users when calculating user similarities. For this, our system creates and uses not only user-item rating matrix, but also user-to-user trust network. As the methods for calculating user similarity between users, we proposed two alternatives - one is algorithm calculating the degree of similarity between users by utilizing in-degree and out-degree centrality, which are the indices representing the central location in the social network. We named these approaches as 'Trust CF - All' and 'Trust CF - Conditional'. The other alternative is the algorithm reflecting a neighbor's score higher when a target user trusts the neighbor directly or indirectly. The direct or indirect trust relationship can be identified by searching trust network of users. In this study, we call this approach 'Trust CF - Search'. To validate the applicability of the proposed system, we used experimental data provided by LibRec that crawled from the entire FilmTrust website. It consists of ratings of movies and trust relationship network indicating who to trust between users. The experimental system was implemented using Microsoft Visual Basic for Applications (VBA) and UCINET 6. To examine the effectiveness of the proposed system, we compared the performance of our proposed method with one of conventional CF system. The performances of recommender system were evaluated by using average MAE (mean absolute error). The analysis results confirmed that in case of applying without conditions the in-degree centrality index of trusted network of users(i.e. Trust CF - All), the accuracy (MAE = 0.565134) was lower than conventional CF (MAE = 0.564966). And, in case of applying the in-degree centrality index only to the users with the out-degree centrality above a certain threshold value(i.e. Trust CF - Conditional), the proposed system improved the accuracy a little (MAE = 0.564909) compared to traditional CF. However, the algorithm searching based on the trusted network of users (i.e. Trust CF - Search) was found to show the best performance (MAE = 0.564846). And the result from paired samples t-test presented that Trust CF - Search outperformed conventional CF with 10% statistical significance level. Our study sheds a light on the application of user's trust relationship network information for facilitating electronic commerce by recommending proper items to users.

• International journal of advanced smart convergence
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• v.9 no.3
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• pp.176-182
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• 2020

In this paper, to analyze the meaning of middle-aged men's economic activities, TEXTOM was used to analyze them. The data collection period is set from 2017 to 2019. Among the collected data, 100 refined words were converted into a matrix in which the degree of social connection was calculated, and the keyword network analysis was performed again with the NetDraw program. According to the study, middle-aged men put more meaning on their current work and family than their future retirement. Also, the related word commonly included in the top five for all three years was 'work'. Related words commonly included in the top 10 were 'old age', 'family', and 'work', and in 2018 and 2019, 'health' was included in the top 10. As a result of this, the middle-aged men living in the modern age are the generation who keep their families through economic activities and are increasingly interested in health and prepare for retirement. Therefore, policy support for stable economic activities is needed to improve the quality of life for middle-aged men. It is necessary to extend the retirement age, expand jobs and provide effective vocational training so that it can handle its role as the head of a family. In addition, measures should be taken to reduce the wage gap between highly skilled and low-skilled workers.

• Journal of the Korean Home Economics Association
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• v.39 no.6
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• pp.109-122
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• 2001

This study was performed to identify the roles of residents for the environmentally sound and sustainable development, taco-polis(kologisches Bauen), eco-village and Symbiotic Housing. These buildings will achieve energy efficiency through design strategies such as passive solar heating system, natural cooling and day lighting. Their infrastructure will feature parking on the periphery, extensive pedestrian paths, outdoor ground lights that preserve stellar visibility, and environmentally sensitive technologies such as low writer use fixtures. And they will restore biodiversity while protecting the wildlife, wetlands, forests, soil, air and water. Their houses wile be designed to support home-based occupations, offering high-speed Internet access and other options to promote a localized, sustainable economy. To support and encourage the evolution of sustainable settlements, it is necessary to prepare constructing the physical facilities and the social functions relating with residents. The roles of residents are important to provide a high Quality lifestyle and to integrate a supportive social environment with a low-impact way of life. This study concluded the four main roles of residents for the sustainable of Eco-polis and Ecovillage. 1. Residents assist transition towards a sustainable society as eco-conscious consumers in the planning stage. 2. Residents live in a ecological way for the sustainable ecovillage. 3. Residents exchange information and education for increasing the community glue as a communication network. 4. Residents support and transmit their cultural vitality and tradition for the next generation. So, users are expected to encourage resident's participation in the planning, design, ongoing management and maintenance of the sustainable ecovillage.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.11
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• pp.4372-4394
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• 2020

The distribution of popular videos incurs a large amount of traffic at the base stations (BS) of networks. Device-to-multi-device (D2MD) communication has emerged an efficient radio access technology for offloading BS traffic in recent years. However, traditional studies have focused on synchronous user requests whereas asynchronous user requests are more common. Hence, offloading BS traffic in case of asynchronous user requests while considering their time-varying characteristics and the quality of experience (QoE) of video request users (VRUs) is a pressing problem. This paper uses social stability (SS) and video loading duration (VLD)-tolerant property to group VRUs and seed users (SUs) to offload BS traffic. We define the average amount of data transmission (AADT) to measure the network's capacity for offloading BS traffic. Based on this, we formulate a time-varying bipartite graph matching optimization problem. We decouple the problem into two subproblems which can be solved separately in terms of time and space. Then, we propose the socially aware D2MD user selection (SA-D2MD-S) algorithm based on finite horizon optimal stopping theory, and propose the SA-D2MD user matching (SA-D2MD-M) algorithm to solve the two subproblems. The results of simulations show that our algorithms outperform prevalent algorithms.

• The Journal of Economics, Marketing and Management
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• v.11 no.2
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• pp.33-46
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• 2023

Purpose: The purpose of this study is to analyze the relationship between characteristics of social media sites (SNS) and the intention of Pakistani tourists to visit South Korea while determining the role of usefulness, interestingness, and involvement of tourists. Research design, data and methodology: A research model was developed through the previous research, and the questioner-based survey was conducted on Pakistani tourists visiting Korea. The survey data was collected by following multiple hypotheses: the relationship between SNS tourism information and perception of SNS, the relationship between SNS perception and intention to visit, and adjustment of involvement in the relation between tourism information characteristics, and SNS perception. We used SPSS and AMOS24.0 statistical tools to analyze the hypothesis testing data. Results: Based on the data analysis, the study found that the characteristics of SNS have a positive effect on intention to visit via users' perception like usefulness and interestingness. The involvement has a moderating effect between SNS characteristics and users' perception. In the group with high involvement, the degree of influence of the quality factor of SNS on user perception was greater than in the group with low involvement. Conclusions: This study demonstrated that traveler's involvement has a moderating effect on the relationship between SNS characteristics and visit intention for Pakistani travelers visiting Korea. It shows that practitioners or researchers should establish and operate SNS strategies in consideration of user involvement.

• KIISE Transactions on Computing Practices
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• v.23 no.4
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• pp.217-225
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• 2017

Recently, the interest in predicting hot topics has grown significantly as it has become more important to find and analyze meaningful information from a large amount of data flowing in social networking services. Existing hot topic detection schemes do not consider a temporal property, so they are not suitable to predict hot topics that are rapidly issued in a changing society. This paper proposes a hot topic prediction scheme that uses a modified TF-IDF in social networking environments. The modified TF-IDF extracts a candidate set of keywords that are momentarily issued. The proposed scheme then calculates the hot topic prediction scores by assigning weights considering user influence and professionality to extract the candidate keywords. The superiority of the proposed scheme is shown by comparing it to an existing detection scheme. In addition, to show whether or not it predicts hot topics correctly, we evaluate its quality with Korean news articles from Naver.

• Journal of Family Resource Management and Policy Review
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• v.12 no.2
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• pp.121-140
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• 2008

The purpose of this study is to guide in providing quality services to meet the needs of married immigrants and their families. The researched agencies in this study were 14 public agencies and local government agencies, 21 married-immigrant family support centers, and 11 community social welfare centers located in the Seoul and Kyung-Gi areas. The program was categorized by the participating researchers, SPSS WIN 12.0 was used to calculate frequency, percentage and average then cross-tabulation was initiated. The results of the study are as follows: 1) The married-immigrant family support centers provide dominant services compared to public agencies and local government agencies, and community social welfare centers are located in the region of Seoul and Kyoung-Gi in the service areas of education, counseling, culture, child care and protect, support group and network. 2) All agencies provide service targeted to married immigrant women and their children 3) Three different types of agencies are mainly focused on providing Korean education programs. Married-immigrant family support centers and community social welfare centers are focused on providing computer skills programs. Public agencies and local government agencies are focused on providing vocation-oriented education. 4) Married-immigrant family support centers were investigated to service to the needs of married-immigrant families through networking with their neighboring communities.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.9
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• pp.2285-2301
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• 2012

Peer-to-Peer (P2P) networks are becoming more and more popular in video content delivery services, such as Video on Demand (VoD). Scalability feature of P2P allows a higher number of simultaneous users at a given server load and bandwidth to use stream service. However, the quality of service (QoS) in these networks is difficult to be guaranteed because of the free-riding problem that nodes download the recourses while never uploading recourses, which degrades the performance of P2P VoD networks. In this paper, a distributed trust model is designed to reduce node's free-riding phenomenon in P2P VoD networks. In this model, the P2P network is abstracted to be a super node hierarchical structure to monitor the reputation of nodes. In order to calculate the reputation of nodes, the Hidden Markov Model (HMM) is introduced in this paper. Besides, a distinction algorithm is proposed to distinguish the free-riders and malicious nodes. The free-riders are the nodes which have a low frequency to free-ride. And the malicious nodes have a high frequency to free-ride. The distinction algorithm takes different measures to response to the request of these two kinds of free-riders. The simulation results demonstrate that this proposed trust model can improve QoS effectively in P2P VoD networks.