• KCID journal
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• v.3 no.1
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• pp.40-52
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• 1996

This study was conducted to simulate long series of synthetic monthly flows by harmonic synthetic and harmonic regression models and to make a comparison of statistical parameters between observed and synthetic flows of six watersheds in Yeong San and Seo

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.5 no.4
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• pp.406-413
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• 1993

Among 2-dimensional coastal hydrodynamic finite element models time stepping ADCIRC and STEPM. and harmonic FUNDY and TEA models were compared in order to find out their characteristics and analyze ernr. General feasibility and capability of models were studied by comparing model results with an analytical solution on some reference points and L$_2$norm error in quarter annular domain where analytical solution can be obtained. According to these tests harmonic models FUNDY and TEA were nearly coinciding with analytical solutions and gave better results than time stepping models. STEPM was at least 5 times better than ADCIRC in L$_2$norm error test and it was 7 times worse than harmonic models. It was expected and concluded that these errors might come from phase lag due to cold start condition and nonlinear effect in basic equations of time stepping models.

• Communications of Mathematical Education
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• v.26 no.2
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• pp.221-249
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• 2012

The purpose of this study is to investigate students decision-making progress through ill-structured problem solving process. For this study, 25 fifth graders in an elementary school were observed by applying ABCDE model (Analyze - Browse - Create - Decision making - Evaluate), and analyzed their decision-making progress analyzing framework which follows 3 steps - making their own decision, discussing/revising with peers, and lastly decision making/solving problem. Upper two groups with better performance in ill-structured problem solving model among 6 groups showed active discussion in group and decision making process with 3 steps (making their own decision, discussing/revising with peers). Even though their decisions are not good-fit to mathematical reasoning result, development and application of ill-structured problems would bring better ability of high level thinking and problem solving to students.

• Environmental and Resource Economics Review
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• v.28 no.4
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• pp.497-526
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• 2019

The importance of "decoupling" to maintain economic growth and reduce greenhouse gases is emerging as the world has been mandated to reduce greenhouse gases since the 2015 Paris Agreement. This study covered 63 countries from 1980 to 2014 and analyzed the main characteristics and causes of decoupling phenomenon between economic growth and carbon emissions. In this study, the degree of decoupling was measured every five years. The analysis found that the decoupling rate of OECD countries and countries with large incomes was high, and that the decoupling phenomenon has accelerated worldwide since the 2000s. However, the degree of decoupling was different depending on the national characteristics. According to the results of dynamic panel model, the growth rate of manufacturing and the proportion of exports hampered decoupling, while the proportion of human capital and renewable energy had a positive effect on decoupling. Also income had a inverse U-shape non-linear effect on decoupling.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.7 no.4
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• pp.355-367
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• 1995

Tidal prediction at a given location has been conventionally made by harmonic method. Another means of tidal prediction is through numerical modeling of tides. Present research focussed on whether prediction of tides and tidal currents can be made everywhere in the Inchon Bay using the numerical model directly or by harmonic constants of tides and tidal currents of the whole Bay derived from the extended model run.

• Journal of Elementary Mathematics Education in Korea
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• v.18 no.2
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• pp.189-209
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• 2014

This study designed and developed a model of ill-structured problem solving and ill-structured problems for the 4th, 5th, and 6th graders. In addition, two sets of ill-structured problems has been explored to 23 4th graders, 33 5th graders, and 23 6th graders in elementary schools in order to investigate their problem solving, creative personality, and mathematical reasoning. The model of ill-structured problem solving was suggested ABCDE (Analyze-Browse-Create-DecisionMaking-Evaluate) model and analyzed participants' problem solving procedure. As results, participants showed improvement between pretest and posttest in problem solving and the high graders showed the greater creative personality.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.5
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• pp.446-456
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• 2007

Numerical analyses of stem waves, the interaction between incident and reflected waves of obliquely incident regular waves along a vertical wall in a constant water depth, are presented. For the numerical model of the analysis, the two-layer Boussinesq equations developed by Lynett and Liu(2004a,b) are employed. Numerical results are compared with both laboratory measurements and those obtained using parabolic approximation model. The overall comparisons between the results from the two numerical models and the experiments are good. However, the two-layer Boussinesq model is more accurate than the parabolic approximation model as the angle of incident waves increases. In particular, the higher harmonic generation due to the wave nonlinearity is captured only in the Boussinesq model.

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.12-13
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• 2003

고차조화파를 이용해 아토초 펄스를 생성시킬 수 있음은 최근 여러 연구자들에 의해 이론적으로 제시되어 왔다. 아토초 펄스의 생성은 기본적으로 고차조화파 발생을 이용하여 생성되므로 고차조화파의 연구가 선행되어야 하며, 이에 대한 연구는 이미 많은 연구자들에 의해 이루어 졌다. 초기에 Kulander 등은 Time dependent Schrdinger equation (TDSE) 을사용하여 수치적으로 계산하여 고차조화파의 이론적 분석을 수행하여 단일원자(single atom)에서 발생하는 고차 조화파의 평탄영역(plateau)과 잘림영역(cutoff) 등을 설명하였고, Corkum 등은 준고전적 (semiclassical) 원자 모델을 사용하는 물리적 모형을 제안하여 이 때 계산된 고차조화파가 실험결과 및 완전한 양자역학적 결과와 유사하게 나타남을 보였다. (중략)

• The Journal of the Korean dental association
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• v.47 no.4
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• pp.206-210
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• 2009

앞에서 임프란트 주변 연조직의 형태를 작업모형에서 재현하기 위한 몇가지 방법을 살펴 보았다. 심미성이 점차 강조되고 있는 추세에 비추어 단순하게 치아의 심미성 보다는 전반적으로 연조직과 경조직이 잘 조화되는 수복물이 요구되고 있다. 잘 만들어진 작업모형은 좀 더 심미적이고 안정된 결과를 얻을 수 있도록 도움이 될 것이다.

• Journal of Korean Society of Transportation
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• v.8 no.1
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• pp.89-102
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• 1990

본 연구에서는 개별모형(disaggregate model)을 이용한 도시권의 교통수요예측 모형체계의 구축을 최종목적으로 하며, 그때 개인이 1일 중에 행하는 복수의 트립에 관한 의사결정간의 상호관계를 적절히 고려함에 의해, 되도록 개인의 교통행동을 논리적으로 설명함과 동시에 모형의 취급이 용이하도록 논리성과 실용성이 잘 조화된 모형의 구축을 시도하였다. 모형의 체계는 비취업자와 취업자 각각의 1일의 통행행태유형의 선택에 관한 2개의 Sub-model로 구성되어져 있다. 본 논문은 그 Sub-model중의 하나인 비취업자의 1일의 통행행태유형(트립발생, 각 트립의 목적지와 교통수단)의 선택에 관한 개별모형의 개발을 행한 것이다. 본 모형의 특징은 tour별 효용최대화행동가설에 기초를 두어 개인이 1일 중에 행하는 각 트립의 선택행동은 해당트립의 전후에 행해지는 트립들의 선택행동의 영향을 고려하여 의사결정을 하는 것으로 가설을 설정하여 트립간의 상호관련성을 표현하였다. 모형의 구조로서는, 모형의 취급이 보다 용이하도록 tour별 효과최대화를 트립단위의 단계형 모형으로 표현하는 nested logit model형의 수차동시효과최대화 모형을 구축하였다 실제의 도시권에 대한 실증적 검토를 행한 결과, 본 연구에서 개발한 별개모형의 유효성이 확인되었다.