• Journal of the Korea Society of Computer and Information
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• v.16 no.3
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• pp.121-129
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• 2011

One of the major challenges of minimum energy consumption for wireless sensor networks(WSN) environment. LEACH protocol is hierarchical routing protocol that obtains energy efficiency by using clustering. However, LEACH protocol in each round, because the new cluster configuration, cluster configuration, whenever the energy consumed shorten the life of the network. Therefore in this paper, the cluster is formed in WSN environment in early stage and the problems with energy waste have been solved by selecting C-node. In the initial round of proposed model uses 26 percent more than traditional LEACH energy consumption. However, as the round is ongoing, it has been proved by the network simulation tool that the waste of energy could be diminished up to 35%.

• Journal of Korea Society of Industrial Information Systems
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• v.19 no.5
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• pp.39-50
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• 2014

Today people use a smartphone as a tool for enjoying personal hobbies or entertaining contents as well as communication media. Most of the traditional game-specific platforms have transferred to smartphones equipped with social network games that integrate games with human relationships. As average life span of most games has been shortened gradually, game companies should be ready to develop new games to meet user needs. In this study we investigate the acceptance of social games, enjoyable by users and their friends linked in social networks. Since user behavior of social games may show cultural differences by country, we perform a comparative study on acceptance of social games between Korean and Chinese users. The structural relationships among factors affecting social game adoption have been analyzed focusing on differences between Korean and Chinese. We analyze similarities and differences of adoption mechanism in two countries and present some practical implications for related industry.

• Journal of Families and Better Life
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• v.34 no.5
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• pp.35-52
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• 2016

The purpose of this study was to compare college students' emoticon use for positive behavior and to analyze the impact of the factors. This study is consisted of 66 questions based on Social demographic characteristics, personality characteristics factors and both scales of emotional expression. The operational test was administered to 340 college students. In an effort to calibrate emoticon use of positive behavior, the results displayed significance differences depending on the gender and grade of the students. Women used more emoticons than men, and freshman used more emoticons than any other year of students. Women used more emoticons such as texts, images, and flash more than men. Students in their freshman year were shown to use more emoticons than students in other grade levels. Emotional expression was strongly related man with personality traits of integrity. Personality traits of sensitivity, openness, intimacy, and sincerity had a significant influence on the emotional expression. An emoticon is, therefore, be a useful tool to express their emotions. Male and female students with higher levels of congeniality had expressed more emotions that were self-defence ambivalent and concerned-relation ambivalent. However, in the case of the female students, those with higher levels of self-defence ambivalent emotional expressiveness had a lower usage of positive emoticons, while male students with higher levels of self-defence emotional expressiveness used more positive emoticons. Higher levels of congeniality among groups that use mobile emoticons with their parents, whether the frequency of use was high or low, were associated with higher levels of self-defence ambivalence and concerned-relation ambivalence. Those with higher levels of sincerity had low levels of self-defence ambivalence and concerned-relation ambivalence, and those with higher levels of concerned-relation ambivalence had higher levels of positive emoticon usage.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.1
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• pp.49-54
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• 2016

The large scaled lead-acid battery is widely used for efficient operation of the photovoltaic system in many islands. However, lithium-ion battery is now being introduced to mitigate the fluctuation of wind power and to replace lead-acid battery. Therefore, hybrid ESS (Energy Storage system) that combines lithium-ion battery with lead-acid battery is being required because lithium-ion battery is costly in present stage. Under this circumstance, this paper presents the optimal algorithm to create composition rate of hybrid ESS by considering fixed and variable costs in order to maximize advantage of each battery. With minimization of total cost including fixed and variable costs, the optimal composition rate can be calculated based on the various scenarios such as load variation, life cycle and cost trend. From simulation results, it is confirmed that the proposed algorithms are an effective tool to produce a optimal composition rate.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.5 s.118
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• pp.1-13
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• 2006

The Attention Restoration Theory (ART) developed by Kaplan and Kaplan proposes that effortful directed attention required in normal life can be fatigued. Restoration can occur in a setting that has restorative qualities. The restorative quality described by the ART involves four concepts: being away, fascination extent, and compatibility. The purpose of this study was to investigate how the restorative quality of landscape influenced the preferences and satisfaction of visitors to an heritage landscape. Four kinds of heritage landscapes of Kyongju were used as environmental surrogates and 150 americans participated in the study. Hartig et al.'s Revised Perceived Restorativeness Scale (RPRS) was used as the psychological measure for the restorative quality, along with other measurement constructs such as cultural uniqueness and novelty. The results showed that RPRS was a reliable measurement tool for assessing the restorative quality of artificial landscapes. Factor analysis identified three valid factors: escape-fascination compatibility, anti-extent. Among the three factors, only two, escape-fascination and compatibility, were found to have important effects on visiting preference and satisfaction. Specifically, higher levels of preference and satisfaction were associated with higher levels of escape-fascination and compatibility. The results indicate that the restorative quality has a high possibility to be used as a frame of reference for assessing various types of landscapes, from natural to artificial. It was also proposed that restorative quality could better explain the experience of the landscape strongly related to specific purpose or motivation.

• Journal of Practical Engineering Education
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• v.8 no.1
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• pp.15-21
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• 2016

TRIZ, the theory of inventive problem solving, is widely used not only in traditional engineering fields such as mechanical, electrical, and electronic engineering but also in IT field and generated good results. Therefore, recently many universities have opened TRIZ as a regular course. Especially, 40 inventive principles of TRIZ are not only creative thinking tools that beginners can learn relatively easily but also very effective problem solving tools, but it is not that easy to utilize it properly for solving real problems as you think. In order to use inventive principles as powerful tools for creative problem solving, it is important to educate learners to use it repeatedly through stimulating their interest about the inventive principles. So, in this paper, we introduce various inventive principles hidden in the cards that can be easily accessible in everyday life, and propose how to educate learners to evoke their interest in the inventive principles through making cards by utilizing the inventive principles.

• Journal of Environmental Impact Assessment
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• v.21 no.1
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• pp.119-132
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• 2012

Biodiversity is a key element of ecosystem of which function provides essential product and service in human life. In the course since development projects often causes damages to biodiversity, environmental impact assessment technique must be capable of accurately assessing potential impact from flora and fauna and to entire ecosystem. Korea needs improvement of its assessment technique that is compatible with Korean environmental regulatory standard that is generally stricter than that of most countries. This study attempts to explore both domestic and overseas biodiversity assessment techniques and analyze each stage of environmental impact assessment. The data is collected from numbers of literatures selected by navigating both domestic and overseas literature database with certain keywords. Among the 44 selected papers, overseas publications outnumber those of domestics, and there are more researches on assessment methodology of biodiversity than assessment tool and model. In terms of environmental impact assessment, the number of papers on environmental impact forecast exceeds the numbers of papers on current state of environment and the impact minimizing solution. Therefore, contents and trends of those researches in the different stages of environmental impact assessment discussed in this paper not only suggest potential impact on biodiversity and minimization solutions in detail, but is also a valuable resource particularly for biodiversity relevant environmental assessment technique improvement in Korea. Proposing of a new direction of improvement in biodiversity assessment techniques makes this study significant, and further research for preservation of biodiversity should follow up to provide an improvement scheme for biodiversity assessment techniques in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.2
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• pp.909-919
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• 2011

Web accessibility for information vulnerable people has been important due to the web sites are recognized as an essential tool in everyday life for information and knowledge acquisition. In addition, since Disability Discrimination Act has been enacted in 2008, the demand for human resources with skills of web accessibility has been increased. However, courses of web accessibility have yet not been provided by domestic universities. In this paper, based on the Tyler model and Instructional System Design(ISD) model, a web accessibility curriculum that can be adopted in domestic universities is developed. To this end, educational goals of web accessibility were set and web accessibility education contents and characteristics were analyzed from 423 domestic universities and 197 universities in 4 foreign countries. Finally, the curriculum was validated by accessibility experts. The suggested curriculum can be applied to web educations for universities and institutions.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.6
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• pp.89-100
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• 2017

The Agricultural Policy/Environmental eXtender (APEX) model was developed to extend EPIC's capabilities of simulating land management impacts for small-medium watershed and heterogeneous farms. APEX is a flexible and dynamic tool that is capable of simulating a wide array of management practices, cropping systems, and other land uses across a broad range of agricultural landscapes. APEX have its own agricultural environmental database including operation schedule, soil property, and weather data etc., by crops. However, agriculture environmental informations the APEX model has is all based on U.S. As this can cause malfunction or improper simulation while simulating highland field. In this study, database for APEX model to be utilized for South Korea established with 44,814 agriculture fields in Pyeongchang-gun, Korea from 2007 to 2016. And assessed domestic applicability by comparing T-P unit load criteria presented by National Institution of Environmental Research and result of APEX model. As a result of APEX model simulation, average T-P value for decade was 6.18. Average T-P of every year except 2011 was in range of 5.37~10.43 and this is being involved into criteria presented by National Institution of Environmental Research. It is analyzed that adjusting slope factor can make the model applicable for domestic agricultural environment.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.6
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• pp.9-18
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• 2017

The objective of this study was to estimate the climate change impact on inflow to Namgang Dam using SWAT (Soil and Water Assessment Tool) model. The SWAT model was calibrated and validated using observed flow data from 2003 to 2014 for the study watershed. The $R^2$ (Determination Coefficient), RMSE (Root Mean Square Error), NSE (Nash-Sutcliffe efficiency coefficient), and RMAE (Relative Mean Absolute Error) were used to evaluate the model performance. Calibration results showed that the annual mean inflow were within ${\pm}5%$ error compared to the observed. $R^2$ were ranged 0.61~0.87, RMSE were 1.37~7.00 mm/day, NSE were 0.47~0.83, and RMAE were 0.25~0.73 mm/day for daily runoff, respectively. Climate change scenarios were obtained from the HadGEM3-RA. The quantile mapping method was adopted to correct bias that is inherent in the climate change scenarios. Based on the climate change scenarios, calibrated SWAT model simulates the future inflow and evapotranspiration for the study watershed. The expected future inflow to Namgang dam using RCP 4.5 is increasing by 4.8 % and RCP 8.5 is increasing by 19.0 %, respectively. The expected future evapotranspiration for Namgang dam watershed using RCP 4.5 is decreasing by 6.7 % and RCP 8.5 is decreasing by 0.7 %, respectively.