• Journal of Korean Society on Water Environment
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• v.25 no.6
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• pp.863-871
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• 2009

For the assessment of climate change impacts on river flow condition, CGCM 3.1 T63 is selected as future climate information. The projections come from CGCM used to simulate the GHG emission scenario known as A2. Air temperature and precipitation information from the GCM simulations are converted to regional scale data using the statistical downscaling method known as MSPG. Downscaled climate data from GCM are then used as the input data for the modified TANK model to generate regional runoff estimates for 44 river locations in Nakdong river basin. Climate change is expected to reduce the reliability of water supplies in the period of 2021~2030. In the period of 2051~2060, stream flow is expected to be reduced in spring season and increased in summer season. However, it should be noted that there are a lot of uncertainties in such multiple-step analysis used to convert climate information from GCM-based future climate projections into hydrologic information.

• Journal of Korean Society for Quality Management
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• v.41 no.1
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• pp.39-52
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• 2013

Purpose: The purpose of this study was to investigate if purchasing companies' efforts of supplier development activities to supplier companies have positive impacts on the purchasing companies' performance as the first step. In the second step, we tried to confirm if the concept of Supply Chain Corporate Social Responsibility activities and Coexistence activities take the roles of moderate variable on relationship between supplier development and three performances respectively. Methods: The collected data through survey were analysed using multiple regression for the first step of the study and moderate regression for the second one of it. Results: The results of this study are as follows; supplier development efforts effect on all three performances positively. Moreover, Supply Chain CSR has significant moderate effect on relationship between supplier management and corporate performances, while Coexistence does between supplier management and logistics performances. In the case of relationship between supplier management and production performances, both Supply Chain CSR and Coexistence show significant moderate effect. Conclusion: Manufacturing companies in Korea need to make effort of supplier development in selective way when they want to practice Supply Chain CSR and Coexistence concurrently considering strategies and objectives.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.2
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• pp.53-63
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• 2016

Monitoring of cyanobacteria bloom in reservoir systems is important for water managers responsible of water supply system. Cyanobacteria affect the taste and smell of water and pose considerable filtration problems at water use places. Harmful cyanobacteria bloom in reservoir have significant economic impacts. We develop a new method for estimating the cyanobacteria bloom using Landsat TM and ETM+ data. Developed model was calibrated and cross-validated with existing in situ measurements from Daecheong Reservoir's Water Quality Monitoring Program and Algae Alarm System. Measurements data of three stations taken from 2004 to 2012 were matched with radiometrically converted reflectance data from the Landsat TM and ETM+ sensor. Stepwise multiple linear regression was used to select wavelengths in the Landsat TM and ETM+ bands 1, 2 and 4 that were most significant for predicting cyanobacteria cell number and bio-volume. Based on statistical analysis, the linear models were that included visible band ratios slightly outperformed single band models. The final monitoring models captured the extents of cyanobacteria blooms throughout the 2004-2012 study period. The results serve as an added broad area monitoring tool for water resource managers and present new insight into the initiation and propagation of cyanobacteria blooms in Daecheong reservoir.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.5
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• pp.777-787
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• 2008

The purpose of this study is to identify impacts of adolescent consumers' assertiveness and appearance concerns on their buying behaviors when they buy school uniforms. This research examined information sources and purchase evaluative criteria as related variables of clothing buying behaviors. The Internet survey was carried out to middle and high school students in Seoul. A total of 907 data were analyzed by factor analysis, frequency analysis and step-wise multiple regression analysis. The results of this study were as follows: From a result of factor analysis on adolescent consumers' assertiveness, appearance concerns and information sources and purchase evaluative criteria for buying school uniforms, each four variances showed factorial structures clearly. School uniform consumers' assertiveness and appearance concerns had significant influences on information sources and purchase evaluative criteria. Especially, an impact of conformity appearance concern was inclined to be high on information sources and purchase evaluative criteria.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.9
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• pp.2098-2117
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• 2012

This paper jointly investigates the bandwidth allocation, transmission strategy and relay positions for two-way transmission aware cellular networks with network coding (NC). Our goal is to minimize the transmission power of mobile terminals (MTs). Consider a cellular system, where multiple MTs exchange information with their common base station, firstly, we propose an efficient bandwidth allocation method and then give a transmission strategy for each MT to determine whether to use relay stations (RSs) for its two-way transmission with the BS or not. To further improve the system performance, the optimal positions of RSs are also jointly discussed. A GA-based algorithm is presented to obtain the optimum positions for RSs. Besides, the impacts of frequency reuse on MT's transmission power and system spectral efficiency (SE) under different number of relays are also discussed in our work. Numerical results show that the proposed NC aware scheme can extend MTs' battery life at least 6% more than traditional method.

• Korean Journal of Health Education and Promotion
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• v.31 no.1
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• pp.27-43
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• 2014

Objectives: The purpose of this study was to evaluate depression of mothers with children in early childhood and to identify predictors by income level. Methods: The research was conducted with 1,761 data from the 3rd wave of the Panel Study of Korean Children(PSKC) data. Independent variables were socio-demographic data, self-esteem, normative life-events, non-normative life events, parenting stress, marital conflict, social support. Data were analyzed by t-test, ANOVA, hierarchical multiple regression analysis were conducted. Results: Significant factors of depression of female in low-income were non-normative life events, parenting stress, marital conflict. In middle class, significant factors were education, birth order of children, self-esteem, normative and non-normative life events, parenting stress, marital conflict, sociable support. At last, we found that marital conflict was the biggest factor for depression of female in low-income and parenting stress was the most powerful predictor in middle class. Conclusions: Mother's depression has a enormous impacts on development of children in early childhood. Therefore It is required to prevent depression in mothers and it is important to intervene at the early stage of depression. Results of this study showed a different pattern of predictors by income level. Therefore, Intervention and services for a mother's depression should change the direction depending on the level of income.

• Journal of Family Resource Management and Policy Review
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• v.12 no.1
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• pp.91-105
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• 2008

This study identifies key determinants and types of participation in UCC Services. The research examines the how the major factors in perception of social presence, fun and entertainment, self-expression, arousal, human relations, positive feedback, information sharing, monetary business opportunity, and user friendliness of web structure contribute to participation in UCC Services. The data used in this study were collected by a web-based survey so that 629 internet users were available for analysis. Some of the practical implications of the results are follows. We have categorized that the type of people participating in UCC Services were readers, modifiers, remixers, and creators. Digital consumers directly connected with other consumers by producing their own digital contents. Multiple regression analysis among the creators group was not included due to small sample size. Self expression, fun and joy and the convenience of the web interface showed strong positive significant impacts on the UCC Service participation of all participation types. Information sharing, other's positive reputation and arousal showed a positive significant impact on the modifiers or remixers type groups. Monetary business opportunity and human relations were not significant in any UCC type group.

• Journal of the Korean Home Economics Association
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• v.50 no.5
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• pp.25-38
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• 2012

Drawing on social and cultural capital theory, the study investigates the influences of social capital and cultural capital on the academic achievement of children in out-of-home care. We collected data from 494 children living in out-of-home services, including institutional care facilities, foster care homes, and group homes. To analyze the collected data, a multiple regression analysis method was used. In addition, the IV (instrumental-variables) estimation was utilized to rule out the possibility of reverse causality. The level of children's social capital was measured through children's relationships with parents and friends, parental monitoring, etc. The level of children's cultural capital was measured by their cultural activities, such as going to museums, and playing musical instruments. Children's personal characteristics and placement history in out-of-home services were used as control variables. We found that among personal characteristic variables, self-esteem, depression and anxiety, and delinquency affected the academic achievement of the children. Cultural capital, but not social capital, positively affected the level of academic achievement of the children. Based on the study results, implications for child welfare practice were discussed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.6C
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• pp.423-428
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• 2008

We consider the use of cooperative diversity in a multiuser wireless data network. This paper provides an analysis of the interaction between cooperative diversity and multiuser diversity on downlink channels. By using approximation of the signal-to-noise ratio (SNR) distribution of each cooperative diversity link by Gamma distribution, an analytic expression is derived for the average throughput of a single-cell wireless system with multiple cooperative diversity links combined with a fair-access scheduler. The proposed analytic approach is verified through comparisons with simulated results and shows that cooperative diversity makes the detrimental impacts on multiuser diversity.

• Journal of Information Technology Applications and Management
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• v.24 no.4
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• pp.215-227
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• 2017

The development of information technology are leading to the rapid evolution of SNS (Social Networking Services) in various directions and industries. Initially, SNS have been used as the form of networking between user's groups. Currently SNS has been developed towards multiple purposes and platforms such as the promotion and the advertising of a company. There are many SNSs including QQ, Weibo, and Wechat and so on in China. However, the use of companies in terms of advertising and information sharing with the customers do not meet the trend in China. Especially, there were little researches for Chinese travel agencies how to utilize SNS for attracting new customers and making them contribute to the firm's performance. In this study, we try to investigate the impact of the firm's characteristics and the usage of SNS on the performance of Chinese travel agencies. Based on Top 100 China travel agencies in 2009, we analyzed the relationships between firm's characteristics and the usage of SNS, and firm's performances in 2013. We expect that our study can contribute to the increasing academic and practical needs on the empirical evidence of the impacts of the SNS utilizations on the firm's performance.