• Journal of Internet Computing and Services
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• v.11 no.3
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• pp.139-148
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• 2010

In the sensor network security area, previous works were mainly concentrated on achieving authentication, confidentiality, integrity and availability. But the ID exposure issue is recently an increasing concern in research community. To protect the ID exposure from various attacks, the most common approach is to make use of a dynamic pseudonym rather than the real ID. However, if a node's secret key (or hash key) and the current pseudonym (such as a random number) are exposed, the attacker can easily generate the previous/next pseudonyms. In this paper, we propose a security infra-structure scheme for enabling strong anonymity of sensor nodes. Our scheme ensures that the probability being able to generate a pseudonym is very low even if a sensor node has been compromised with an attacker. Security analyses have proven that our scheme is suitable for sensor network environments in terms of preserving of forward anonymity as well as backward anonymity.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.3
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• pp.428-451
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• 2010

Traffic matrix-based anomaly detection and DDoS attacks detection in networks are research focus in the network security and traffic measurement community. In this paper, firstly, a new type of unidirectional flow called IF flow is proposed. Merits and features of IF flows are analyzed in detail and then two efficient methods are introduced in our DDoS attacks detection and evaluation scheme. The first method uses residual variance ratio to detect DDoS attacks after Recursive Least Square (RLS) filter is applied to predict IF flows. The second method uses generalized likelihood ratio (GLR) statistical test to detect DDoS attacks after a Kalman filter is applied to estimate IF flows. Based on the two complementary methods, an evaluation formula is proposed to assess the seriousness of current DDoS attacks on router ports. Furthermore, the sensitivity of three types of traffic (IF flow, input link and output link) to DDoS attacks is analyzed and compared. Experiments show that IF flow has more power to expose anomaly than the other two types of traffic. Finally, two proposed methods are compared in terms of detection rate, processing speed, etc., and also compared in detail with Principal Component Analysis (PCA) and Cumulative Sum (CUSUM) methods. The results demonstrate that adaptive filter methods have higher detection rate, lower false alarm rate and smaller detection lag time.

• Journal of KIISE
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• v.44 no.1
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• pp.78-83
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• 2017

Finding the densest subgraphs from social networks, such that people in the subgraph are in a particular community or have common interests, has been a recurring problem in numerous studies undertaken. However, these algorithms focused only on finding the single densest subgraph. We suggest a heuristic algorithm of the bottom-up type, which finds the densest subgraph by increasing its size from a given starting node, with the repeated addition of adjacent nodes with the maximum degree. Furthermore, since this approach matches well with parallel processing, we further implement a parallel algorithm on the MapReduce framework. In experiments using various graph data, we confirmed that the proposed algorithm finds the densest subgraphs in fewer steps, as compared to other related studies. It also scales efficiently for many given starting nodes.

• Korean Institute of Interior Design Journal
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• v.24 no.6
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• pp.192-201
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• 2015

This research aims to find planning issues on reuse of an industrial heritage as a cultural cluster and to suggest planning factors which can be referred when designing the similar cases. Analysis standards were formed through reviewing of precedent literatures, and the selected cases(i.e Shanghai M50, Yokohama BankART1929, and Incheon ArtPlatform) were analyzed to identify both physical and nonphysical planning characteristics. By combining analyses, the following results were obtained; (1) The demand and supply of the arts coexist in one place, and the studios and galleries are designed with high ceilings; (2) The regional and historical characteristics are revealed from preserving major architectural elements of previous buildings, and open spaces are provided to promote a variety of activities for local residents; (3) Various strategies to overcome disadvantage in location are developed, and the concepts of design can be easily recognized by buildings' exterior as the reused industrial heritage and the cultural cluster; (4) Diverse supports for artists make it possible to gather many competent artists, and the cooperative networks among artists play a pivotal role in the development of cultural cluster; (5) The cluster runs educational programs reflecting the needs of local residents, and builds a strong relationship with the local community by supporting regional art industry or developing linked programs; (6) The cluster serves various functions such as cafes, pubs, restaurants, art shops, and bookstores, and hosts appealing events and festivals to attract many people even who are not interested in arts.

• Asian Journal for Public Opinion Research
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• v.8 no.3
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• pp.265-296
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• 2020

Macao, a special administrative region of China, has been able to maintain the records of zero deaths and keep confirmed cases under 50 since the outbreak of COVID-19 for more than half a year as of July 2020, despite being the world's most densely populated city. The current paper utilizes the dialogic public relations theory to analyze the situation using both literature review on how the various government actions and strategies during the pandemic were corresponding to the theory, and a quantitative random digital dialing (RDD) telephone survey, with a sample of 502 Macao residents aged 18 or above, to study the public reactions towards the government pandemic prevention actions. Survey results show a high level of public satisfaction towards epidemic prevention performance, as well as some forms of collaborative information redissemination behavior in social media platforms. Literature review and analysis from dialogic theory found that spirit of mutual equality, collaboration with local community, immediacy of presence in crisis time, engagements with stakeholders through maximum media channels and networks, supportiveness to public with both useful information and practical social support like subsidy program, as well as commitment to transparent and genuine communication, are all the dialogic communications strategies that describe what the Macao government has done in the crisis of COVID-19. The dialogic strategies that could be learned from the Macao government may be used as a reference for similar urbanized and densely populated cities in other territories.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.9B
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• pp.760-766
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• 2008

As a backbone network, wireless mesh network (WMN) aims to provide reliable high throughput network connectivity to wireless users. Recent research has focused on routing and channel allocation to increase the capacity of wireless mesh backbones. Wireless mesh networking is an attractive solution for home, community, and enterprise networks as it is a self-configuring, instantly deployable, and lowcost networking system. In this paper, we empirically evaluate and analyze charateristic of WMN to establish WMN testbed by measurement. We use laptops and net4826 Soekris board widely used. Soekris boards are equipped with one network interface card (NIC) or above in our measurements. We also use paket generator, routing demon tools and so on. Throughout this measurements, we show limitation of Soekris board and software we use, and suggest guideline to establish WMN.

• Journal of Families and Better Life
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• v.27 no.2
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• pp.123-138
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• 2009

The purpose of this study was to investigate the social inclusion of permanent rental and lot-sold apartment and to provide basic source of their physical and social inclusion. The research method was in-depth interview for 32 residents in two apartment complex based on the social inclusion index developed in the previous study. The results of the study were summarized as follows: First, the majority of the residents' average monthly income in the permanent rental apartment were lower than the minimum cost of living. But, they were not seriously realized it and gave up any economic activities due to their poor health and age. Second, the big different indexes from the residents in lot-sold apartment were the family networks and social activity participations. They were not satisfied with their family members, seldom had social gatherings, and did not have any information of community cultural events. Third, since they had narrow sphere of activities, they could not properly evaluate the diversity of neighborhood facilities and the convenience of public transportations. But, they obviously recognized anti-social behaviors and the invasion of the privacy in the apartment complex, and maintained superficial neighborship. Fourth, on the other hand, the residents in lot-sold apartment had the feeling of being harmed by the various troubles of the permanent rental apartment.

• Korean journal of communication and information
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• v.39
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• pp.506-543
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• 2007

The purpose of this study is to explore the relationship between national reputation, culture and communication based on the intercultural communication theory. The 18 foreign residents in Korea were interviewed. The analysis of in-depth interview reveals that culture and communication are very important factors in establishing the national reputation. The qualitative research showcases that the cultural acculturation types(separation, integration, and assimilation) are grouped as foreigners adapt and acculturate to the residence. Especially, the assimilation is very essential type in having the in-group expectancy and the loyalty to Korea. The results reveal that a higher level of heterogeneity of a personal network('Korean in-group network') is associated with a higher level of reputation and loyalty to Korea. This suggests that having outgroup members in individuals' personal networks facilitates outgroup communication competence and loyalty to Korea.

• Journal of Families and Better Life
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• v.27 no.1
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• pp.89-105
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• 2009

A family resilience approach aims to identify and fortify key interactional processes that enable families to withstand and rebound from disruptive life challenges. Walsh(1998) described family belief systems, organizational patterns, and communication processes as the three main keys of family resilience. The purpose of this study was to identify the three key factors of family resilience in case of divorced female single-parent families in Korea. The study participants were seven divorced mothers who were living in the institutional facility for female single-parent families. Using a qualitative approach, in-depth interviews were audiotaped and transcribed verbatim for analysis. The study findings were as follows. First, the participants showed positive thinking rather than fear about the adversity induced by the divorce. They also showed the senses of competence, control, and self-esteem. However, the senses of transcendence and spirituality were barely evident. Second, emotional and economic supports from parents, brothers and sisters, and community networks (i.e., mother-child protection institution, healthy family support center) enhanced the family resilience of the participants. Third, the participants showed clear communication, open emotional expression, and shared decision making. This study suggests that more counseling services and parent education be provided by healthy family support center and institutional facilities as important family resilience factors for divorced female single-parent families who are below the poverty line.

• The Journal of the Korea Contents Association
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• v.14 no.10
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• pp.189-197
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• 2014

The purpose of this study is to examine factors influencing adolescents' suicidal ideation and provide foundational data to reduce adolescents' suicidal ideation and prevent their suicide based on that. According to the research results, there was no significant difference found in demographic characteristics. And depression, stress, and social support exerted significant influence on suicidal ideation. As depression and stress became higher, suicidal ideation increased. When other factors were controlled, suicidal ideation increased if social support was provided less. Based on the study results, the study has made political suggestions as follows: first, regarding the family support system, it is needed to adopt institutional approaches so that they can participate in many different types of education to improve relationship between parents and children. Second, about the school support system, it is necessary to develop programs to form teacher and peer support relations and build the friend support resource system. Third, in terms of the community support system, it is required to build an integrated support system to form diverse local networks.