• Journal of KIISE:Software and Applications
• /
• v.32 no.8
• /
• pp.789-794
• /
• 2005

LDA (Linear Discriminant Analysis) provides the projection that discriminates the data well, and shows a very good performance for face recognition. However, since LDA provides only one transformation matrix over whole data, it is not sufficient to discriminate the complex data consisting of many classes like honan faces. To overcome this weakness, we propose a new face recognition method, called LDA mixture model, that the set of alf classes are partitioned into several clusters and we get a transformation matrix for each cluster. This detailed representation will improve the classification performance greatly. In the simulation of face recognition, LDA mixture model outperforms PCA, LDA, and PCA mixture model in terms of classification performance.

• Korean Journal of Food Science and Technology
• /
• v.35 no.4
• /
• pp.648-652
• /
• 2003

Precise and rapid method out for distinguishing blended sesame oils through the electronic nose analysis was developed. Sesame oil was blended with corn oil at the ratio of 95 : 5, 90: 10, and 80 : 20 (w/w), respectively. Samples were then analyzed by gas chromatography, SPME-GC/MS, and the electronic nose composed of 12 different metal oxide sensors. Sensitivities $(delta\;R_{gas}/R_{air})$ of sensors from electronic nose were analyzed by principal component analysis (PCA). Proportion of the first principal component was 98.76%.

• Journal of the Korean Institute of Gas
• /
• v.25 no.4
• /
• pp.49-56
• /
• 2021

Liquefied Petroleum Gas is divided into liquefied gases containing propane (C₃H₈) and butane (C₄H₁₀). The quality of LPG varies greatly depending on the composition of the mixture, so it is important to measure the composition accurately. It is difficult to determine the composition of the mixture because liquid and gas coexist at room temperature. Therefore, the uncertainty in determining the concentration of hydrocarbons by component is high, and there are many problems that differ from the actual content standard. Therefore, it is necessary to develop a mixed liquid propane standard gas for the composition and accurate concentration of hydrocarbon substances. Mixed liquid propane standard gas is manufactured into bellows-type constant-pressure cylinders by ISO-6142 (2015). The homogeneity of the four standard gases manufactured was confirmed to be GC-FID. The manufacturer's uncertainty of expansion was 0.01 % to 0.30 % and homogeneity was 0.03 % to 0.25 %. In this mixed liquid propane standard gas, the relative expansion uncertainty of weight method, manufacturing consistency, cylinder adsorption and long-term stability was developed within 0.26 %-1.3 9% (95% of confidence level, k=2).

• Ecology and Resilient Infrastructure
• /
• v.8 no.3
• /
• pp.135-142
• /
• 2021

Biopolymers have been known as eco-friendly soil strengthening materials and studied to apply levees. However, the effect of biopolymer on vegetation is not fully understood. In this study, we analyzed the root growth of Camelina sativa L. (Camelina) when the xanthan gum was amended to soil in Aluminum (Al) stress conditions. Amendment of 0.05% xanthan gum increased root growth of Camelina under Al stress conditions. Under the Al stress condition, expression of aluminum activate malate transporter 1 (ALMT1) gene of Camelina root was induced but showed a lower level of expression in xanthan gum amended soil than non-amended soil. Additionally, the binding capacity of xanthan gum with Al ions in the solution was confirmed. Using morin staining and ICP-OES analysis, the Al content of the roots in the xanthan gum soil was lower than in the non-xanthan gum soil. These results suggest that xanthan gum amended soils may reduce the detrimental effects of Al on the roots and positively affect the growth of plants. Therefore, xanthan gum is not only an eco-friendly construction material but also can protect the roots in the disadvantageous environment of the plant.

• Korean Journal of Food Science and Technology
• /
• v.34 no.6
• /
• pp.984-991
• /
• 2002

Oxidative stability and flavor of sesame oil blended with canola oil (Ca), corn oil (Co), and soybean oil (Sb) at ratios of 90 : 10, 70 : 30, and 50 : 50 (w/w), respectively, were evaluated. Oxidative stability of sesame oil increased with the addition of vegetable oils (10, 30, and 50% of Ca and Co, and 10% of Sb). Pyrazines, pyrroles, pyridines, and thiazoles, good contributors to the characteristic flavor of sesame oil, were also found in sesame oil blended with vegetable oil. The sensory evaluation showed that no difference was observed between sesame oil and sesame oil blended with 10% of Ca, Co or Sb, which showed higher oxidative stability.

• Journal of The Korean Association For Science Education
• /
• v.20 no.4
• /
• pp.542-561
• /
• 2000

The purpose of this study was to investigate the relationships among elementary school teachers' high school and college backgrounds in science, their attitudes toward teaching science, their science teaching efficacy beliefs, and their instructional strategies. Both quantitative and qualitative research methodologies, were utilized in this study. This paper, however, presents only the results of the quantitative data analysis while expecting to report the qualitative data analysis outcomes afterwards. Four instruments were used to ascertain information concerning teachers' backgrounds in science(the number of high school science courses they took and the grades of courses, the number of college science courses and grades, the number of college science methods courses and grades), attitudes toward teaching science, science teaching self-efficacy beliefs(personal science teaching efficacy and science teaching outcome expectancy), and their instructional strategies(indirect, direct, and mixed methods). A sample of 340 practicing elementary school teachers participated in this study. To determine statistically significant results, Pearson's correlation coefficient was used to relate teachers' backgrounds in science, attitudes toward teaching science, science teaching self-efficacy beliefs and their instructional strategies. The correlation coefficients were statistically significant regarding four variables, teachers' backgrounds in science, attitudes toward teaching science, science teaching self-efficacy beliefs, and instructional strategies investigated in this study. These results can be interpreted that programs of teacher preparations and trainings which include science and science methods courses should help prospective and practicing teachers change in their attitudes and beliefs toward science teaching. It is expected that future studies concerning teachers' attitudes, beliefs, and behaviors toward teaching science can help to improve science teacher education in Korea.

• Journal of KIISE:Software and Applications
• /
• v.36 no.12
• /
• pp.1024-1027
• /
• 2009

In this letter, we evaluate the classification performance of mixed numeric and categorical data for comparing the efficiency of feature filtering and feature wrapping. Because the mixed data is composed of numeric and categorical features, the feature selection method was applied to data set after discretizing the numeric features in the given data set. In this study, we choose the feature subset for improving the classification performance of the data set after preprocessing. The experimental result of comparing the classification performance show that the feature wrapping method is more reliable than feature filtering method in the aspect of classification accuracy.

• Korean Journal of Food Science and Technology
• /
• v.30 no.5
• /
• pp.1035-1039
• /
• 1998

Phase separation is the typical phenomenon in protein-polysaccharide mixtures because of thermodynamic incompatibility between two macromolecules. Phase separations of casein-alginate-water systems were investigated by using phase diagram under varying pH (6, 8 and 10) and NaCl concentrations (0, 0.25 and 0.5 M). Incompatibility decreased with increasing pH and decreasing NaCl concentration. Molecular weight of alginates did not significantly affect the phase diagram of casein-alginate-water systems. The results strongly suggested that compatibility of casein and alginate involved electrostatic interactions.

• Journal of Life Science
• /
• v.6 no.1
• /
• pp.27-33
• /
• 1996

Reactions taken place by a mixed culture of Lactococcus lactis subsp. cremoris KH (lac$^{+}$ prt$^{+}$ ) and KHA (lac$^{-}$ prt$^{-}$ ) and KHA (lac prt ) in cheese ripening have been investigated. Growth characteristics of the mixed culture showed commensalism, and the amounts of proteinases of the mixed culture were small enough. From these results, it is concluded that the production of bitter taste by the mixed culture is a small matter, even if the density of the mixed culture is highly maintained during cheese ripening. Hence, the mixed culture of KH and KHA cells could be a good cheese starter in accelerating the process of cheese ripening.

• Journal of KIISE
• /
• v.42 no.5
• /
• pp.601-608
• /
• 2015

In order to answer questions successfully on behalf of the human contestant in DeepQA environments such as 'Jeopardy!', the American quiz show, the computer needs to have the capability of fast temporal and spatial reasoning on a large-scale commonsense knowledge base. In this paper, we present a hybrid spatial reasoning algorithm, among various efficient spatial reasoning methods, for handling directional and topological relations. Our algorithm not only improves the query processing time while reducing unnecessary reasoning calculation, but also effectively deals with the change of spatial knowledge base, as it takes a hybrid method that combines forward and backward reasoning. Through experiments performed on the sample spatial knowledge base with the hybrid spatial reasoner of our algorithm, we demonstrated the high performance of our hybrid spatial reasoning algorithm.