• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.6
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• pp.1142-1147
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• 2015

As a method to increase the scalability and efficiency of wireless sensor networks, a scheme to construct networks hierarchically has received considerable attention among researchers. Researches on the methods to construct wireless networks hierarchically have been conducted focusing on how to select nodes such that they constitute a backbone network of wireless network. Nodes comprising the backbone network should be connected themselves and can cover other remaining nodes. A problem to find the minimum number of nodes which satisfy these conditions is known as the minimum connected dominating set (MCDS) problem. The MCDS problem is NP-hard, therefore there is no efficient algorithm which guarantee the optimal solutions for this problem at present. In this paper, we propose a novel multi-start local search algorithm to solve the MCDS problem efficiently. For the performance evaluation of the proposed method, we conduct extensive experiments and report the results.

• Journal of the Korean association of regional geographers
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• v.19 no.4
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• pp.775-786
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• 2013

Although the Dept. of Geography in Korea has contributed to the social development of Korea with a remarkable growth for a short period, their social status and influence have not greatly improved and the graduates in Geography do not have many job opportunities. The low social statue and the limited job opportunities of the Dept. of Geography in Korea was due to the failure of the creation of their demand and the expansion of their sphere in response to the social changes and developments of Korea. In France, the Dept. of Geography has raised their social standings through the suited curriculum system to generate their demand and enlarge their domain with the social changes and development of French. The Dept. of Geography in Korea also needs not only the expansion of sphere but the building of the proper curriculum system for the creation of demand.

• Journal of the Korean association of regional geographers
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• v.8 no.3
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• pp.364-379
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• 2002

The purpose of this study is to search for a rationale of world geography curriculum. Elementary school children tend to get impressionistic and distorted information about other countries through snapshot TV programs. But they need to get more balanced understanding about them from the perspective of each country. Children's judgment about other countries, favorable or unfavorable, tends to be emotional, based on the first-order conditions of life in those regions, such as atmosphere, food, and habitat, and the symbolics of the place. But their systematic understanding about the relationship between their own life and the life of other locations or countries tends to be meager. It seems to be partly due to the practice of co-centric curricular construction. The geography curriculum may have to be in relation to other countries, from the regional geography of the third grade on.

• Management & Information Systems Review
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• v.30 no.4
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• pp.441-474
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• 2011

This purpose of this study is to examine the relationships of ethical leader and ethics management system with employees's organizational citizenship behavior and the mechanism underlying these relationships. A questionnaire survey was conducted involving 1,035 full-time employees from large and medium industries in Daegu and Gyeong-buk provinces. Regression analysis was used to test the hypotheses. The results showed that both of ethical leader and ethics management system were positively related with employees's organizational citizenship behavior. As expected, these relationships were mediated by organization-oriented ethical climate and social responsibility-oriented ethical climate respectively. The findings of this study are as followings: First, employees tend to show their pro-social behavior when they perceive their leaders act ethically and ethics management is well institutionalized. Second, building up the organization-oriented ethical climate and social responsibility-oriented ethical climate can be a powerful strategy to enhance employees's organizational citizenship behavior.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.813-816
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• 2010

최근 지속가능한 개발의 개념은 국제적으로 경제 개발과 환경 보전 사이에서 논쟁이 중심이 되고 있으며, 수자원 개발과 관리는 이들 논쟁에서 중요한 부분을 차지하고 있다. 이와 더불어 유역을 관리함에 있어 수자원을 이수, 치수 및 수질의 단일 문제로 인식하는 것이 아니라 통합적으로 인식하는 유역통합관리(Integrated Watershed Management, IWM)의 필요성이 대두되고 있다. 이에 본 연구는 유역통합관리에 앞서 유역의 상태 및 문제점을 파악하기 위한 방법으로 EEA (European Environment Agency)에서 개발한 추진력(Driving force)-압력(Pressure)-상태(State)-영향(Impact)-반응(Response) (DPSIR) 개념 이용하여 3개의 세부 지표인 이수지표, 치수지표, 수질지표로 구성된 하나의 통합 지수인 유역수자원평가지수를 개발하였다. 세부지표인 이수지표는 연속무강우일수, 인구밀도, 용수수요, 물재이용률 등 16개의 구성요소, 치수지표는 홍수범람위험 지역 내 거주 인구수, 홍수방어시설용량, 개수율, 100 mm 이상 강수일수 등 15개의 구성요소, 수질지표는 BOD (Biochemical Oxygen Demend) 부하량, 수질 등급, 연중 목표 수질 달성일수 등 13개의 구성요소로 이루어져있다. 이를 북한강 유역 중 북한 지역을 제외한 유역 즉, 수자원단위지도 상의 춘천댐권역(1010) ~ 청평댐권역(1015)의 6개 중권역에 적용하여 비교하였다. 세부지표의 주된 요소인 유출량의 모의를 위해 장기유출모형인 HSPF (Hydrological Simulation Program - Fortran)를 사용하였다. 모형에 입력된 유역평균강수량 자료는 1973년 ~ 2008년까지의 37년의 자료기간을 갖는 북한강유역의 5개 기상관측소 자료를 Thiessen network를 이용하여 산정하였다. 본 연구를 통해서 북한강 유역의 현재 수자원의 상태를 지수화하여 나타내고 그 결과를 비교해보았다. 이 결과는 유역 수자원의 파악하여 유역통합관리시 유역의 문제점을 파악하고 이를 수정하기 위한 의사결정 우선순위를 정하는데 사용될 수 있다.

• Korean Journal of Construction Engineering and Management
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• v.15 no.4
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• pp.139-149
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• 2014

Lifeline service disruptions can have significant impacts on local community in the aftermath natural disaster. Although effective restoration strategies with accurate damage assessment are required, the internal complexity of lifeline networks and their interdependency makes the understanding restoration process of lifeline systems a difficult issue. Additionally, the limitations of previous research relating the influence assessment of lifeline to community disaster resilience, highlight the need for understanding of lifeline networks. Therefore, this paper presents an agent-based model to discover emergent behavior and evaluate the interdependency and resiliency in lifeline networks. This research will provide basic guideline of resource allocation in order to mitigate cascading failures of the post disaster restoration processes.

• Journal of the Korean association of regional geographers
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• v.22 no.4
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• pp.912-930
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• 2016

This paper suggests to bring the idea of social construction of nature or social nature discussed in social science including geography to geographical and environmental education for breaking traditional divide of people(or society) and nature. And this paper analyzed relationship between people and nature, meaning of environment and the concepts of social nature represented in the geography curriculum and textbook of England, Australia and Korea. Recently in terms of focusing disciplines or education on integration or convergence, introduction of social nature in teaching and learning geography and environment has an important implication. With rapid growth of capitalism, nature is constructed socially by the political, economical, social and cultural practice. Thus geography education reduces the distance between human geography and physical geography and needs to focus on exploring not just the relationship between people and nature but social construction of nature. Another implication of the introduction of social nature in teaching and learning geography and environment is that students can develop the relational sensitivity about the relationship people and nature or people and place.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.10
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• pp.1317-1322
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• 2021

Nonlocal similarity of natural images leads to the fact that a patch matrix whose columns are similar patches of the reference patch has a low rank. Images corrupted by additive white Gaussian noises (AWGN) make their patch matrices to have a higher rank. The noise in the image can be reduced by obtaining low rank approximation of the patch matrices. In this paper, an image denoising algorithm is proposed, which first constructs the patch matrices by combining the similar patches of each reference patch, which is a part of the noisy image. For each patch matrix, the proposed algorithm calculates its low rank approximate, and then recovers the original image by aggregating the low rank estimates. The simulation results using widely accepted test images show that the proposed denoising algorithm outperforms four recent methods.

• International Area Studies Review
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• v.16 no.1
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• pp.221-239
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• 2012

The purpose of this paper is to investigate the impact of internet shopping motivations on information searching intention, customer satisfaction and purchase intention. To achieve this goal, literature review and empirical studies were conducted in parallel. The results of this study are as follows: First, the motives of internet shopping of Chinese consumers were found to be in four dimensions, "seeking convenience," "seeking low-cost," "seeking variety" and "seeking pleasures", in order of large proportions, respectively. Second, Among these four internet shopping motivations "seeking convenience,""seeking variety" and "seeking pleasures" were found to have direct, significant and positive effects on information searching intention. But "seeking low-cost" has no positive effects on information searching intention. Third, information searching intention was found to have direct impact on customer satisfaction and purchase intention. Fourth, Customer satisfaction has an direct and positive effects on purchase intention.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.12
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• pp.2392-2400
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• 2015

Zigbee, which was a representative standard technology for dealing low energy and mesh networks in large deployment area such as smart home, smart building, and massive sensor networks, has been developed and deployed for increasing communication area by using Ad hoc method. It has been originally developed based on IEEE 802.15.4 standard so every node needs 48bit unique address defined by IEEE. However, it is absolutely inefficient to assign an unique address to every communication node where it would be deployed through large-scale network area, e.g., smart lighting and massive sensor networks, because there could be variously multiple companies to deploy network infrastructure and they could have different policy to assign node ID. To prevent the problem, this paper proposes a method of dynamic PANID assignment in overall Personal Coordinators, and also proposes a method for addressing PANID conflict problem which could be derived from dynamic PANID assignment.