• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.716-721
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• 2010

LCA (Life Cycle Assessment) carried out to estimate carbon footprint and to establish of LCI (Life Cycle Inventory) database of rice production system. The results of collecting data for establishing LCI D/B showed that organic fertilizer and chemical fertilizer input to 4.29E-01 kg $kg^{-1}$ rice and 2.30E-01 kg $kg^{-1}$ rice for rice cultivation. It was the highest value among input for rice cultivation. And direct field emission was 3.23E-02 kg $kg^{-1}$ during rice cropping. The results of LCI analysis focussed on greenhouse gas (GHG) was showed that carbon footprint was 8.70E-01 kg $CO_2$-eq. $kg^{-1}$ rice. Especially for 80% of $CO_2$ in the GHG and 7.02E-01 kg of its $CO_2$-eq. $kg^{-1}$ rice. Of the GHG emission $CH_4$, and $N_2O$ were estimated to be 13% and 5%, respectively. With LCIA (Life Cycle Impact Assessment) for rice cultivation system, it was observed that fertilizer process might be contributed to approximately 80% of GWP (global warming potential).

• Journal of Wetlands Research
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• v.21 no.spc
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• pp.80-89
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• 2019

The purpose of this study is to analyze the relationship between SPI (Standardized Precipitation Index) meteorological drought and RDI (Reservoir Drought Index) agricultural drought for Geum river basin. Drought Indices was calculated by collecting data of precipitation and agricultural reservoir water storage rate from 2014 to 2016. To evaluated the correlation between meteorological and agricultural drought, the Pearson correlation and the Receiver Operation Characteristic (ROC) analysis were conducted to evaluate the correlation between meteorological and agricultural droughts. The SPI-6 and RDI showed the highest relationship with Pearson coefficient 0.606 and ROC hit rates 0.722 respectively, and the spatial occurrence patterns of drought using overlapped SPI-6 and RDI, the big differences between the 2 indices were occurred in the upstream areas of Miho stream and Nonsan stream from August to October 2015. The analysis using reservoirs specifications for areas where reservoir droughts occurred was conducted, and the areas showing severe drought of RDI were the reservoir areas having relatively small value of basin magnifying power (BMP). This means that a reservoir has the reaction capability for agricultural drought mainly depending on the reservoir BMP.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.1
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• pp.10-18
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• 2011

Purpose: The purpose of this study is to find out the effects of bisphosphonates (BPs) on the proliferation and the alkaline phosphatase (ALP) activity of human bone marrow derived mesenchymal stem cells (hMSCs), and thus state its correlation with bisphosphonate related osteonecrosis of the jaw (BRONJ). Methods: hMSCs was obtained by collecting and culturing cancellous bone fragments from a patient undergoing iliac bone graft. Alendronate (Aln) and Pamidronate (Pam), Ibandronate (Ibn) were added to the culture media in the concentration from $10^{-3}$ M to $10^{-11}$ M and cell toxicity, viability were measured. For ALP activity evaluation, Aln and Pam were added to the culture media in the concentration from $5{\times}10^{-7}$ M to $1{\times}10^{-8}$ M and were cultured for 1 week, 2 weeks and 3 weeks. ALP activity data were standardized using protein assay. Control groups were prepared for each examination. Results: Aln, Pam and Ibn all failed to increase the proliferation of hMSCs. With 1 week, 2 weeks of $5{\times}10^{-8}$M of Aln treatment, the ALP activity increased. Pam treatment increased the ALP activity with 2 weeks of $5{\times}10^{-8}$ M and$1{\times}10^{-8}$M. Also Ibn treatment increased the ALP activity with 2 weeks of $5{\times}10^{-8}$ M and $1{\times}10^{-8}$ M. Conclusion: It is considered that BPs are not capable of improving the proliferation of hMSCs. Also, after a transient increase in the ALP activity with the lower concentration of BPs, the activity decreased again. Therefore, in patients on long-term medication of BPs, the proliferation and osteoblast differentiation of hMSCs are restrained, and thus delayed wound healing and increase in BRONJ complications may occur.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3296-3303
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• 2010

This study attempted to identify the strategic factors of conflict management in making decisions of family travel by age focusing on the different conflicts occurred in the family travel currently in Korea. by doing this, it tried to provide the basic data that can draw out constant participation, higher involvement and commitment by identifying the strategies for conflict management centering around not only tourism studies of tourist psychology and behavior but also the strategic variables of conflict management in terms of the promotion of tourism industry. To examine the result of this study, first, it was found that in all age groups, strategies of compromise and moderation strategy to meet the needs of surrounding people and the person him/herself were used as a strategic plan for conflict management between decision-makers and conflicting groups. Second, it was analyzed that when a conflict is caused, from order to negotiation strategies; from authority to democratic strategy, they turned out to make efforts to solve the conflicts occurred during family travel by collecting the opinions of the surrounding people; tune the opinions; and make decisions by majority. Lastly, it was found that they turned out to make efforts to ease the conflicts caused during family travel through active problem-solving regarding internal/interpersonal/structural restriction factors.

• Journal of Korean Library and Information Science Society
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• v.37 no.3
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• pp.59-73
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• 2006

The purpose of this paper was to empirically examine college students' on-line bookstore utilization status. The focus of this study was placed on three major issues. First. what are the college students' motivations in using on -line' bookstore. Second. what are the major determinants of college students' on -line bookstore utilization. Third. how book genres are related to students' on -line bookstore utilization behavior. Data were collected from 215 college students during October 10, 2005 to October 17, 2005. The analyses showed following results: First, the college students' on -line bookstore utilization motivations were grouped into three areas-convenience motivation, interaction motivation, and information collecting motivation. Second. college students who were oriented toward convenience motivation, who were more interested in on-line bookstores, and who were more satisfied with on-line services, made more frequent visits to on-line bookstore sites. Third, college students who allocated less time to book readings showed a tendency of buying books through on-line bookstores. Finally, college students who were more interested in on -line bookstores showed more satisfaction and bought such various books as literature, hobby or practical books, foreign novels, and general readings. This finding suggests that in order to activate on-line bookstore business. book industries, especially the publishers and/or distributors, have to develop new ideas which can make an appeal to college students who are believed to be critical book readers.

• Journal of Korean society of Dental Hygiene
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• v.12 no.5
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• pp.881-896
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• 2012

Objectives : The purpose of this study was to examine the amount of daily fluoride intake among children using fluoride-containing dentifrice in an effort to pave the way for the selection of criteria for the development of safe dentifrice for different age groups to make a contribution to children's oral health. Methods : This study was implemented over approximately six months from May to October 2008 by recruiting subjects, asking their consent, conducting a survey, collecting samples and analyzing the collected data. The subjects in this study were preschool residents in Seoul and Gyeonggi province, who were at the western age of 2 to 5. The amount of fluoride withdrawn from their one-time toothbrushing was measured in two different ways. One was by using HMDS-facilitated modified diffusion method and fluoride ion electrode, and the other was by applying ion chromatography without the diffusion procedure. Results : The fluoride intake accounted for $46.5{\pm}19.1$ percent of the amount of fluoride used, and that percentage was statistically significantly different according to age(p<0.01). The one-time fluoride intake from dentifrice per weight(kg) was a mean of $0.009{\pm}0.006mg$. As a result of multiplying this amount by daily toothbrushing frequency, the daily fluoride intake from dentifrice per weight(kg) appeared to be $0.023{\pm}0.016mg$ on average. There was a large difference among the children in that regard, since that ranged from a low of 0.003mg to a high of 0.070mg. And age made a statistically significant difference to that(p<0.01). Conclusions : The above-mentioned findings of the study showed that the children's daily fluoride intake from dentifrice per weight was lower than the recommended daily fluoride intake from diets per weight for young children aged 1 to 12(0.05-0.07mg). However, there was a great disparity among the children in that aspect, and they are likely to take more fluoride from other things as well. Therefore it is required to prepare separate criteria for preschool and school-aged children.

• Archives of design research
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• v.18 no.1 s.59
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• pp.69-80
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• 2005

So far, there have been mary studies on human emotions and the emotional side of products in the field of emotional engineering. Contemporary emotion-related researches have focused mainly on the relationship between product aesthetics and the emotional responses elicited by the products, but little is known about emotions elicited from using the products. In this study we have extracted some emotional words that can come up during user interaction with a product and reveal emotional changes. Firstly, we assembled a set of emotional words that were sufficient to represent a general overview of Korean emotions, collected from various literature studies in the field of psychology, linguistics, emotional engineering. Secondly, we found emotional words from collecting user opinion on the website. In this study, we used heavy traffic websites such as shopping mall and mania sites. Finally the emotional words were collected from verbal protocols by using Think Aloud technique. The collected words were integrated according to standards and they were applied on evaluation survey twice for evaluating their appropriateness. This survey was conducted for identification of emotional expressions while using a product. Finally, we extracted 88 emotional words for measuring user's emotions expressed while using products. And we categorized the 88 words to form 6 groups by using factor analysis. The 6 categories that were extracted as a result of this study, such as aesthetics, satisfaction in usability, novelty, uncomfortable- ness, pleasure and excellence were found to be user's representative emotions expressed while using products. It is expected that emotional words and user's representative emotions extracted in this study will be used as subjective evaluation data that is required to measure user's emotional changes while using a product.

• Journal of the Korean Society for information Management
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• v.24 no.1 s.63
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• pp.301-319
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• 2007

Nowadays the information environment enables users to access the traditional library collection as well as various digital information resources. In this rapidly changing environment, the use of digital information resources such as web sites, data, and homepages has increased. In this research, highly-cited authors' research outcomes as well as the research outcomes of the people, who cited the highly-cited authors' works, were extracted then compared with information stored in the medical colleges' digital libraries and the academic information portals in the clinical medicine area by using the citation information provided by Essential Science Indicators from ISI Web of knowledge. Out of 10,000 authors,146 people's homepages, which present research outcomes, were analyzed. The research outcomes listed in the homepages included journal papers, monographs, conference proceedings, and lecture notes. About 15% of the journal papers, 32% of the monographs, 48% of the conference proceedings, and 100% of lecture notes were accessible only through the homepages. The research outcomes accessible from the homepages were almost analogous to the ones available through the medical college's digital libraries and the academic information portals. Therefore, the digital library collection will be improved and expanded quantitatively and qualitatively by collecting and using the information in the homepages of the prestigious researchers.

• Journal of Korea Society of Industrial Information Systems
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• v.19 no.1
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• pp.13-18
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• 2014

Sensor nodes are used for monitoring and collecting the environmental data via wireless sensor network. The wireless sensor network with various sensor nodes draws attention as a key technology in ubiquitous computing. Sensor nodes has very small memory capacity and limited power resource. Thus, it is essential to have energy efficient strategy for the sensor nodes. Since the sensor nodes are operating on the same frequency bands with ISM frequency bands, the interference by the devices operating on the ISM band degrades the quality of communication integrity. In this paper, the convolutional code is proposed instead of ARQ for the error control for the sensor network. The proposed convolutional code was implemented and the BER performance is measured. For the fixed transmitting powers of -19.2 dBm and -25dBm, the BER with various communication distances are measured. The packet loss rate and the retransmission rate are calculated from the measured BER. It is shown that the porposed method obtained about 9~12% and 12-19% reduction in retransmission rate for -19.2 dBm and -25 dBm respectively.

• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.1
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• pp.22-29
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• 2004

An international project, known as Argo, for collecting data on temperature, salinity and velocity of currents in the world's oceans, has been started in the year 2000 and the full Argo array of approximately 3000 floats will be deployed by 2006. 18 countries deployed 1,023 floats, which are operating in the ocean of the world as of December 2003. In the present study, we tried to predict float distribution and a rate of drifting ashore of the floats after their termination based upon a product of the ocean general circulation model of JAMSTEC (Japan Marine Science and Technology Center). We first evaluated reliability of the model prodilct quantitatively by comparing trajectories of surface buoys of WOCE Surface Velocity Program (SVP) and those predicted by the model surface current field. It is found that the model is acceptable for practical application to deploy floats and to estimate those trajectories. 653 particles at 3-degree spacing are used to investigate the ratio of floats drifted ashore, given that during the first 4 years floats cycle between the surface and 2000m for 10 days and then floats are on just the surface for 100 years. The simulation indicates that about 29% of deployed floats will be drifted ashore within 100-year.