• Proceedings of the Korean Information Science Society Conference
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• 2012.06b
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• pp.384-386
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• 2012

최근, 온라인 소셜 네트워크 서비스의 사용자가 크게 늘어나면서 온라인 사용자들의 특성을 연구하기위한 방안으로 소셜 네트워크 분석이 주목받고 있다. 그러나 대부분의 소셜 네트워크 분석 방법은 두 노드 사이의 최단경로를 계산해야하므로 계산 시간이 오래 걸리는 단점이 있다. 본 논문에서는 휴리스틱 탐색방법의 하나인 최상우선 탐색 방법을 온라인 소셜 네트워크에 적합하도록 수정한 최단경로 탐색 방법을 제안한다. 제안한 방법은 그래프에서 아크의 개수를 평가 값으로 사용하는 휴리스틱 함수를 사용하며 탐색의 효율성을 위하여 경사트리를 제거한 후 경로를 탐색한다. 그리고 검증을 위하여 약 16만 사용자로 구성된 실제 온라인 소셜 네트워크를 수집하여 너비우선 탐색 방법과 비교 실험을 하였다. 실험 결과, 본 논문에서 제안한 방법이 너비우선 탐색 방법에 비해 정확도는 80% 정도로 다소 떨어지지만 계산 속도가 약 7.4배 향상됨을 확인하였다. 본 논문에서 제안한 방법은 소셜 네트워크 분석의 시간을 향상시켜 여러 분야에서 사회 현상 및 동향을 다양하게 분석하는데 유용하다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.6A
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• pp.948-956
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• 2001

이 논문에서는 직접수열 부호분할 다중접속 시스템의 여러 경로 감쇄 환경에서 MMSE 검파기의 성능을 분석한다. 1부에서 MMSE 검파기의 성능을 유도하기 위하여, 필터의 출력단에서 신호를 제외한 나머지 간섭과 배경 잡음 성분을 정규 분포와 근사한 것을 이용하여 여기서는 채널 추정에 오류가 있을 때의 영향을 검토한다. 채널변수에 정규분포의 오류가 있을 때와 구체적인 채널 추정 시스템을 사용한 두 가지 경우에 대해서 채널 추정의 영향을 분석한다. 감쇄 환경, 채널 추정 오류의 분산, 도플러 주파수 등을 변화시켜 얻은 수식적인 결과로 성능 분석의 정확도를 보였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.4
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• pp.737-747
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• 1997

performance of the cellular CDMA overlay system is analyzed which shares the same band with existing microwave narrowband system to enhance the spectral efficiency. To suppress the interfreence from narrowband system, we used a linear predicition filter that adopts the adaptive least mean square algorithm. Alalyzing the performance in the Personal Communication Services channel, characterized as a multipath Rician fadng channels, we considered the power control to solve the near-far problem, and-off and multipath diversity. We also considered interleaving and channel coding to improve BER performance of the CDMA system.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.1
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• pp.1-9
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• 2021

In this paper, we propose an IoT-based traffic safety pedestrian system for the elderly by factor analysis. The proposed system performs a factor analysis of the elderly safety variables and uses the analysis results to provide an optimal path for the elderly. In order to verify the performance of this system, we experimented with performance measurements on elderly pedestrian paths. As a result, we confirm that it provides a better safety path than mobile navigation.

• Environmental and Resource Economics Review
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• v.17 no.1
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• pp.83-120
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• 2008

Small and medium sized enterprises' (SMEs) environmental performance and activities have been often of great concern toward sustainability as they have been playing a critically important role in the economic and industrial development. Among many initiatives to engage SMEs into the sustainability framework, Supply Chain Environmental Management (SCEM) of large companies has a great potential to persuade SMEs to adopt environmentally improved activities. This study investigated the relationship between SCEM approaches of large companies and environmental activities of SMEs in the Korean electronics industry. A postal questionnaire survey was used as a data collection method, and factor analysis and regression analysis were applied to analyse the collected data. The empirical findings suggested that SCEM approaches of large companies have positive impacts on environmental activities of SMEs. Among SCEM approaches, the collaborative approach was more effective than the arm's-length approach. Additionally, this study found positive impacts of trans-national SCEM approaches on SMEs' environmental activities.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.628-638
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• 2019

The purpose of this study was to investigate the characteristics of consumers purchasing environmentfriendly forest products, and to examine the factors affecting consumption expansion. A survey was conducted among 400 consumers over the age of 20 years. A logistic regression analysis was performed based on age, income, gender, level of education, residence area, whether or not they had children, satisfaction with product price, and product reliability. The results revealed that females were more likely to consume environment-friendly forest products than males; married people tended to buy more environment-friendly forest products than single people; and respondents with a high level of education and with children consistently showed higher willingness to purchase environmentfriendly forest products. To expand consumption of environment-friendly forest products, marketing strategies targeting well-educated, female consumers with children should be implemented.

• Journal of Convergence for Information Technology
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• v.8 no.3
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• pp.99-105
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• 2018

The purpose to this study is to analyze the difference of trust toward Internet-only bank into two groups according to the gender. We specially examined whether there is any gap in the determinant of trust. For this, we attempted to analyze the significance of the difference in the path coefficients between the gender through latent mean and path analysis. As a results, the difference of the determinant of trust between the male and the female group occurred in the factor of benefit and security. Moreover, it reconfirmed that trust are later strongly extended to relationship commitment. These findings suggest that it's very important to establish a trust with customers.

• The KIPS Transactions:PartA
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• v.9A no.2
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• pp.171-180
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• 2002

The effective and accurate data flow problem analysis uses the dominator tree and DJ graphs. The data flow problem solving is to safely reduce the flow graph to the dominator tree. The flow graph replaces a parse tree and used to accurately reduce either reducible or irreducible flow graph to the dominator tree. In this paper, in order to utilize Tarian's path compress algorithm, the Top node finding algorithm is suggested and the existing delay reduction algorithm is improved using Path compression. The delayed reduction a1gorithm using path compression actually compresses the pathway of the dominator tree by hoisting the node while reducing to delay the DJ graph. Realty, the suggested algorithm had hoisted nodes in 22% and had compressed path in 20%. The compressed dominator tree makes it possible to analyze the effective data flow analysis and brings the improved effect for the complexity of code optimization process with the node hoisting effect of code optimization process.

• Journal of Distribution Research
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• v.9 no.1
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• pp.67-92
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• 2004

This study investigates the effects of relationship characteristics on the adoption of online distribution channels in Korea. A questionnaire survey of 81 domestic manufacturing companies revealed that relationship characteristics have no effects on the range of products sold through online channels. In terms of functional usage, manufactures' dependence and their perceptions of middlemen's opportunism were found to affect the extent of adoption of online channels. Overall, these two variables were significantly related to such functions as delivery, refunding, and A/S that have been traditionally considered efficient when implemented by the middlemen. None of the relationship characteristics was found significantly related to the adoption of online channels as a tool of information provision. The authors discuss the theoretical and practical implications of the findings.

• Journal of Educational Research in Mathematics
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• v.27 no.2
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• pp.207-225
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• 2017

With a significant role of textbooks in shaping students' opportunities to learn, textbook analysis is essential to reveal these opportunities to learn the concept of area and volume. This research aims to show how the Korean textbooks pace students' learning of area and volume across grades by scrutinizing the textbooks with students' developmental sequences, called learning trajectories. Tasks about area and volume in all Korean elementary textbooks (grade 1 to 6) are coded with the specific developmental stages suggested in learning trajectories. As a result, we find considerable misalignment between the textbooks and the learning trajectories. The textbooks provide opportunities to experience developmental progressions of area and volume later than ages suggested in the learning trajectories. In addition, learning opportunities are significantly concentrated in grade 5 for area and grade 6 for volume with heavy emphases on applying formulas of area or volume. The findings from this research provides important implications concerning design of textbooks as well as improving students' opportunities in the mathematics classrooms.