• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.12
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• pp.1190-1196
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• 2004

Significant air temperature increases in urban areas are known as the heat island phenomenon in a global scale. Therefore, we propose numerical model in order to analyze quantitative effects of building environmental factors on the heat island phenomenon in urban area. In this paper, we propose a predicting model to analyze the heat island phenomenon quantitatively. Using this model, numerical simulation is performed in order to analyze quantitative effects of many factor on the heat island phenomenon.

• Journal of the Ergonomics Society of Korea
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• v.10 no.1
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• pp.29-40
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• 1991

This study deals with a quantitative analysis of the effects of colors on learning effectiveness. First, sensuous or emotional factors that school children feel about colors of teachers' clothes are measured by SD method and analyzed by factor analysis. Second, sensuous or emotional factors to enhance learning effectiveness are measured by SD method from teachers, and principal factors are extracted by factor analysis. Finally, the analysis of interaction between the effects of colors and the learning effectiveness is done using the sensuous or emotional factors found from the previous two analyses. The results are as follows: (1) For in-class concentration, the principal factors are "stable", and "near" feelings. The colors related to these feelings are black, red, and blue. (2) For question inducing, the first principal factors are "soft" and "stable" feelings, and the colors are white and black. The second principal factors are "gentle" and "refined" feelings, and the colors are orange and black. (3) For extra-curricular activity, the principal factors are "artless" and "plain" feelings, and the color is blue.

• Journal of the Korean Statistical Society
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• v.34 no.2
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• pp.141-151
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• 2005

Under the assumption that the three-level factors are quantitative, the linear effects are taken more attention than the quadratic effects of the interaction terms. Webb (1971) presented some small incomplete factorial designs that are mixed two- and three-level designs with 20 or fewer runs. The designs provided the estimating linear-by-linear components of interactions between the three-level factors; moreover, they could also offer estimation of interactions that interest the experiments. Webb used ad hoc methods to find these plans; hence, there was still no unified structure to those experiments. In this paper, we develop the methods to construct the $2^{n}3^3$ and $2^{1}3^3$ designs. The designs constructed by these methods not only supply orthogonal estimates of all the main effects but also permit estimation of all the two-factor interactions not involving the quadratic effects. Furthermore, the designs we find are nearly orthogonal.

• Korean Institute of Interior Design Journal
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• v.21 no.5
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• pp.343-354
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• 2012

Museums in Korea have experienced continuing quantitative growth since the late Choson Dynasty. However, a careful examination of visitors' viewing behavior has not been properly performed. Accordingly, social education for visitors in museums is not properly conducted despite the vast amount of information that museums possess. Given these circumstances, this study which focuses on the factors that influence visitors' behavior in museums intends to examine the effects that the configuration of exhibition space and the resulting visitor circulation patterns have on visitors' behavior with regard to visitor density. From this perspective, and considering five public historical museums within the seoul metropolitan area of korea, a correlation analysis has been conducted based upon quantitative analysis related to the configuration of exhibition space and visitors' observed viewing behaviors. The result of our study is that the configuration of exhibition space influences the patterns of visitor circulation, distribution of space, and the subsequent state of visitor density. Accordingly, the effects of visitor density on the viewing speed and other viewing behaviors could be identified. Based on these findings, the configurational differences in exhibition spaces were identified as one of the key factors that influence visitors' viewing behaviors.

• The Journal of Internal Korean Medicine
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• v.27 no.1
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• pp.138-148
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• 2006

Objectives: This study was designed to investigate the effects of Injinchunggan-tang(Yinchenqinggan-tang) on expression of angiogenic factors in HepG2 cells. Materials and Methods : The mRNA expression levels and protein secretion levels of angiogenic factors were measured using quantitative RT-PCR, Western blot and ELISA assay respectively in Injinchunggan-tang-treated and untreated HepG2 cells. Results : Injinchunggan-tang(Yinchenqinggan-tang) reduced mRNA expression levels and protein secretion levels of angiogenic factors, especially VEGF, bFGF and $TGF{\beta}1$ in HepG2 cells. Conclusion: Results indicate that Injinchunggan-tang (Yinchenqinggan-tang) inhibits expression of angiogenic factors in HepG2 cells. Further, results suggest that Injinchunggan-tang (Yinchenqinggan-tang) inhibits angiogenic effects in HCC.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.51-56
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• 1998

In this paper, we analyze the effects of scaling factors on the performance of a fuzzy logic controller(FLC). The quantitative relation between input and output variables of FLC is obtained by using a qualsi-linear fuzzy model, and an approximate transfer function of FLC is dervied from the comparison of it with the conventional PID controller. Then we analyze in detail the effects of scaling factor using this approximate transfer function and root locus method. Also we suggest an on-line tuning method for scaling factors which employs an sample performance function and a variable reference for tuning index.

• Bulletin of the Korean Chemical Society
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• v.26 no.1
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• pp.85-90
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• 2005

MX and its analogs are synthesized and modeled by quantitative structure activity relationship (QSAR) study including comparative molecular field analysis (CoMFA). As a result, factors affecting this class of compounds have been found to be steric and electrostatic effects. Because hologram quantitative structure activity relationship (HQSAR) technique is based on the 2-dimensional descriptors, this is free of ambiguity of conformational selection and molecular alignment. In this study we tried to include all the data available from the literature, and modeled with the HQSAR technique. Among the parameters affecting fragmentation, connectivity was the most important one for the whole compounds, giving good statistics. Considering additional parameters such as bond specification only slightly improved the model. Therefore connectivity has been found to be the most appropriate to explain the mutagenicity for this class of compounds.

• Journal of ILASS-Korea
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• v.2 no.4
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• pp.36-46
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• 1997

The present study investigated the effects of MTV(Manifold Throttle Valve) on the fuel distribution and the flame stability in a SI engine at cold, idling condition. For the quantitative measurement of fuel distribution with PLIF method, compensating techniques of various factors such as laser beam nonuniformity, background image and local OTF nonuniformity were developed. As a result, it was found that MTV had a positive effect on the air-fuel mixing and flame stability.

• KDI Journal of Economic Policy
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• v.44 no.2
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• pp.45-71
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• 2022

This paper studies potentially relevant factors affecting changes in the number of self-employed in Korea during the period of 1986-2018. The number of self-employed had increased steadily until 2002 but started to decrease around that time and had continued to decline. The increasing trend in the number of self-employed during 1986-2001 is mostly explained by demographic changes, whereas the declining trend during 2002-2018 cannot be explained by demographic factors. In this study, I consider four institutional factors that potentially affect the decrease in the number of self-employed after 2002: i) a decrease in the job-separation rate of wage workers, ii) an increase in the income tax rate applied to the self-employed, iii) an increase in minimum wages, iv) an expansion of unemployment insurance benefits. Using a search and matching model with the self-employed, I quantify the effects of these four factors on the decrease in the number of self-employed during 2002-2018. Quantitative results show that the impact of the increase in the minimum wage is relatively large, whereas the effects of the other three factors are limited. The increase in the minimum wage accounts for approximately 17.5% (0.169 million) of the decrease in the number of self-employed during 2002-2018 (0.964 million).

• Nuclear Engineering and Technology
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• v.33 no.6
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• pp.596-604
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• 2001

This paper quantitatively presents the effects of important factors of the probabilistic safety assessment (PSA) of safety-critical digital systems. The result which is quantified using fault tree analysis methodology shows that these factors remarkably affect the system safety. In this paper we list the factors which should be represented by the model for PSA. Based on the PSA experience, we select three important factors which are expected to dominate the system unavailability. They are the avoidance of common cause failure, the coverage of fault tolerant mechanisms and software failure probability. We Quantitatively demonstrate the effect of these three factors. The broader usage of digital equipment in nuclear power plants gives rise to the safety problems. Even though conventional PSA methods are immature for applying to microprocessor-based digital systems, practical needs force us to apply it because the result of PSA plays an important role in proving the safety of a designed system. We expect the analysis result to provide valuable feedback to the designers of digital safety- critical systems.