• Journal of The Korean Association For Science Education
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• v.25 no.2
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• pp.111-121
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• 2005

The purpose of this study was to analyze characteristics of experimental design and evidence choice of the elementary school students in problem solving process related to controlling variable. For this study, 96 6th grade students were selected and tested with Science Reasoning Task. This study revealed that the types of experimental design were categorized as variance of control variable, controlling of causal variable, perfect controlling variable, imperfect controlling variable, variance of all variable. Prior belief had a strong influence on student's experimental design. The types of evidence choice were categorized as perfect controlling variable, controlling causal variable, variance of causal variable. The degree of controlling variable in evidence choice process was much lower than that in experimental design. Most students tended to choose evidence according to prior belief without controlling variable. The results of this study implied that student's prior belief and characteristic of science process skills should be considered to develop program for promoting controlling variable ability.

• Journal of the Korea Society of Computer and Information
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• v.18 no.3
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• pp.141-152
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• 2013

This study investigates the determinants of users' continuance intention in mobile application market, and examines the structural relationships between predictors and users' continuance intention. Based on the intensive review of prior research related to Internet and mobile services, mobile application richness, brand awareness, user habit, user loyalty were selected as the predictors of users' continuance intention. Using 259 surveys, the research model was assessed and the research hypotheses were tested. The findings show that mobile application richness is positively related with brand awareness and user loyalty. Brand awareness is proven to be a key predictor of user habit and user loyalty. Futhermore, it is shown that user habit has a direct impact on user loyalty and users' continuance intention. Finally, it was proven that user loyalty is a pretty important determinant of users' continuance intention.

• Journal of Wetlands Research
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• v.23 no.2
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• pp.144-153
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• 2021

In recently, the green algae bloom is one of the most severe challenges. The seven days prior prediction is in operation to issues the water quality warning, but it also needs a longer time of prediction to take preemptive measures. The objective of the study is to establish a method to conduct a 3-month prior prediction of Chl-a concentration in the Daechong Lake and tested its applicability as a supplementary of current water quality warning. The historical record of water quality in the Daechong Lake and seasonal forecasting of ECMWF were obtained, and its time-series characteristics were analyzed. The Chl-a forecasting model was established using a correlation between Chl-a concentration and meteorological factor and NARX model, and its efficiency was compared.

• Radiation Oncology Journal
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• v.18 no.4
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• pp.244-250
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• 2000

Purpose : To see the relationship between the response to chemotherapy and the final outcome of neoadiuvant chemotherapy and radiotherapy in patients with mocanry advanced hypopharyngeal cancer. Methods and Materials :A retrospective analysis was done for thirty-two patients with locally advanced hypopharyngeal cancer treated in the Seoul National University Hospital with neoadiuvant chemotherapy and radiotherapy from August 1979 to July 1997. The patients were treated with Co-60 teletherapy unit or 4MV or 6MV photon beam produced by linear accelerator. Daily fractionation was 1.75 to 2 Gy, delivered five times a week. Total dose ranged from 60.8 Gy to 73.8 Gy. Twenty-nine patients received continuous infusion of cisplatin and 5-FU. Other patients were treated with cisplatin combined with bleomycin or vinblastin. Twenty-four (75$\%$) patients received all three prescribed cycles of chemotherapy delivered three weeks apart. Six patients received two cycles, and two patients received only one cycle. Results :The overall 2-year and 5-year survival rates are 65.6$\%$ and 43.0$\%$, respectively. 5-year local control rate is 34$\%$. Organ preservation for more than five years is achieved in 12 patients (38$\%$). After neoadjuvant chemotherapy, 24 patients achieved more than partial remission (PR): the response rate was 75$\%$ (24/32). Five patients had complete remission (CR), 19 patients PR, and 8 patients no response (NR). Among the 19 patients who had PR to chemotherapy, 8 patients achieved CR after radiotherapy. Among the 8 non-responders to chemotherapy, 2 patients achieved CR, and 6 patients achieved PR after radiotherapy. There was no non-responder after radiotherapy. The overall survival rates were 60$\%$ for CR to chemotherapy group, 35.1$\%$ for PR to chemotherapy group, and 50$\%$ for NR to chemotherapy group, respectively (p=0.93). There were significant difference in five-year overall survival rates between the patients with CR and PR after neoadjuvant chemotherapy and radiotherapy (73.3$\%$ vs. 14.7$\%$, p<0.01). The prognostic factor affecting overall survival was the response to overall treatment (CR vs. PR, p<0.01). Conclusion :In this study, there were only five patients who achieved CR after neoadiuvant chemotherapy. Therefore the difference of overall survival rates between CR and PR to chemotherapy group was not statistically significant. Only the response to chemo-radiotherapy was the most important prognostic factor. There needs to be more effort to improve CR rate of neoadjuvant chemotherapy and consideration for future use of concurrent chemoradiotherapy.

• Proceedings of the Korea Association of Information Systems Conference
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• 2003.05a
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• pp.107-125
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• 2003

• Proceedings of the KHMA Conference
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• 2010.05a
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• pp.343-343
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• 2010

• 한국도로학회지:도로
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• v.11 no.3
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• pp.13-19
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• 2009

• Proceedings of the KWS Conference
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• 2002.05a
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• pp.258-259
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• 2002

• CDE review
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• v.6 no.1
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• pp.37-44
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• 2000

자동차 산업의 CALS추진 현황을 설명하기 앞서 간단하게 CALS의 개요를 알아보고 현재 추진 중인 자동차 CALS 선행연구 사업의 내용을 소개하기로 한다.

• Proceedings of the Safety Management and Science Conference
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• 2004.05a
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• pp.105-116
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• 2004