• Journal of the Korean Data and Information Science Society
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• v.28 no.5
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• pp.1021-1026
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• 2017

Mixture experiments are commonly encountered in many fields including food, chemical and pharmaceutical industries. In mixture experiments, measured response depends on the proportions of the components present in the mixture and not on the amount of the mixture. Statistical analysis of the data from mixture experiments has mainly focused on a continuous response variable. In the example of quantal response data in mixture experiments, however, the tumor incidence data have been analyzed in Chen et al. (1996) to study the effects of 3 dietary components on the expression of mammary gland tumor. In this paper, we compared the logistic regression models with linear predictors such as second degree Scheffe polynomial model, Becker model and Akay model in terms of classification accuracy.

• Journal of Korea Port Economic Association
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• v.26 no.4
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• pp.88-100
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• 2010

This paper investigates the influence of industrial activity volatility and exchange rate volatility on import container volume of the Korea during the 1999:1- 2010:9. Conditional variance from the GARCH(1, 1) model is applied as the volatility. The Johansen multivariate cointegration method and the error correction (general-to-specific) method are applied to study the relationship between import volume and its determinants. The empirical results show that volatility has statistically significant negative effect on import volume.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.379-384
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• 2006

Since the monolithic ceramic substrate was introduced for automotive catalytic converters, the durability of the substrate has been a continuing requirement to reduce the emission gas of vehicle. The substrate can occupy a volume as small as 82 $cm^3$ and as large as 8200 $cm^3$ to provide the required substrate for catalytic activity. The long-term durability varies with the size of the substrate from manufacture's point of view. Therefore This study presents that the response surface model using central composite design can explain size effect on the modulus of rupture in a cordierite ceramic monolithic substrate.

• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.12-13
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• 2000

진행파형 광 검출기는 전기적으로 분포된(distributed) 구조이므로, 그 대역폭은 RC 시정수에 의해 제한되기보다는 광 흡수계수와 광과 마이크로파 사이의 진행속도 차에 의해 제한된다$^{(1)(2)}$ . 진행파형 광검출기에서 광과 마이크로파 사이의 속도 부정합이 대역폭에 미치는 영향은 속도 부정합 임펄스 반응(velocity-mismatch impulse response)의 제시를 통해 이미 분석되었다$^{(1)(2)}$ . 그러나, 대역폭에 제한에 큰 영향을 미칠 것이 예상되는 진성 흡수 영역에서의 전송자 표류 시간은 아직 구체적으로 고려되지 않았다. 본 논문에서는 진성 흡수영역에서의 전송자 표류 시간을 고려하였다. 그 전이 시간(transit time)을 고려하기 위해 속도 부정합 임펄스 반응을 수정하여 제시하였다. 새로히 제시된 임펄스 반응은 광 도파로 해석과 진성 영역 분할에 의해 모델화 되었으며, 이 임펄스 반응을 통해 전이 시간과 속도 부정합이 대역폭에 미치는 영향을 살펴보았다. (중략)

• Communications of Mathematical Education
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• v.16
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• pp.201-215
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• 2003

이 연구에서는 창의적인 문제해결능력을 검사하는 도구로 널리 알려진 개방형 문항 5 문제를 수정 또는 번역하여 중학교 2학년 학생들에게 적용하고 그 결과를 분석하였다. 검사도구에 대한 양호도 분석 결과는 다음과 같다. 첫째, 문항 내적 일관성 신뢰도(Cronbach ${\alpha}$)의 계수는 0.8이다. 둘째, 문항반응이론에 근거한 문항의 적합도 지수는 모두 1.2미만으로서 분석모형에 적합한 문항이라고 볼 수 있다. 또한, 문항간의 난이도의 차이는 로짓트 점수가 0.6을 넘지 않은 범위에서 골고루 분포되어 있다. 셋째, 문항 신뢰도 지수가 모두 0.80보다 높은 것으로 나타나 사용된 문항들은 서로 잘 분리되어 창의적 문제해결력을 추정하고 변별하는데 무리가 없다. 학생들의 반응에 대한 분석 결과는 다음과 같다. 문항1에서 곡선을 이용한 반응은 영재학생들에서만 발견할 수 있었다. 문항2에 대한 각 반응의 독창성 점수는 모두 0이다 이것은 문항2가 널리 알려진 문제에 기인한 것으로 해석된다. 문항3은 영재학생들이 더 많은 반응을 보인 것으로 모든 반응이 독창성 점수를 부여받았다. 문항4에 대하여 일반학생들은 거의 반응을 하지 못하였다. 문항5는 대부분의 학생이 반응을 하였으며 반응의 종류도 가장 다양하였다.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.4
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• pp.11-20
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• 2004

This paper suggests the site-dependent ductility factor which is a key component of response modification factor(R). To compute the ductility factor, a group of 1,860 ground motions recorded from 47 earthquake was considered. Based on the local site conditions at the recording station, ground motions were classified into four groups according to average shear wave velocity. This site classification was consistent with site categories of the UBC(1997), NEHRP(1997) and IBC 2000(1997). Based on the results of regression analysis, a simplified equations were proposed to compute site-dependent ductility factors. The proposed equations were relatively simple and provide a good estimation of mean ductility factors. Based on the proposed equation, ductility factors considering the site conditions can be evaluated in accordance with the present building codes.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.6 s.40
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• pp.67-72
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• 2004

In this study the overstrength factors of medium to low-rise bucking restrained braced frames (BRBF) were evaluated. Various design variables, such as number of stories, span length, yield strength of the brace, level of earthquake load, and the response modification factors. The overstrength factors were obtained using the nonlinear static analysis following the procedure proposed by ATC-19. According to the analysis results, the overstrength factors obtained from this study were generally larger than those proposed in 'AISC/SEAOC Recommended Provisions for BRBF'.

• Journal of Korean Society of Steel Construction
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• v.22 no.4
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• pp.325-334
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• 2010

In this study, an unbraced five-story steel-framed structure was designed in accordance with KBC2005 to understand the features of structural behavior for the arrangement of semi-rigid connections. A pushover analysis of the structural models was performed, wherein all the connections were idealized as fully rigid and semi-rigid. Additionally, horizontal and vertical arrangements of the semi-rigid connection were adopted for the models. A fiber model was utilized for the moment-curvature relationship of the steel beam and the column, and a three-parameter power model was adopted for the moment-rotation angle of the semi-rigid connection. The top displacement, base-shear force, required ductility for the connection, sequence of the plastic hinge, and design factors such as the overstrength factor, ductility factor, and response modification coefficient were investigated using the pushover analysis of a 2D structure subjected to the equivalent static lateral force of KBC2005. The partial arrangement of the semi-rigid connection was found to have secured higher strength and lateral stiffness than that of the A-Semi frame, and greater ductility than the A-Rigid frame. The TSD connection was found suitable for use for economy and safety in the sample structure.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.10a
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• pp.265-272
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• 1999

there is no earthquake resistant design code for the unreinforced masonary(URM) buildings in Korea. But it does not mean that all URM buldings in Korea is safe under the possible extent of an earthquake. The purpose of this study is in the inelastic analysis of unreinforced masonary walls with many different types of openings and carry out their ductilities an strengths, response modification factor of each wall has been compared and the most appropriate response modification factor for URM building in Korea has been proposed.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.09a
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• pp.231-238
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• 2003

The overstrength factor and the ductility factor are the two important factors that determines response modification factors used in current seismic codes. The objective of this paper is to obtain the overstrength and ductility factors of special concentric braced frames. For this purpose pushover analysis is performed with model structures until the maximum inter-story drift reaches 2.5% of story height. According to the analysis results, the overstrength factors increase as the height of structures decreases and the span length increases. Ductility factors for mid-story structures turns out to be higher than the other structures and span length does not contribute much to ductility factors.