• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.66 no.4
• /
• pp.258-262
• /
• 2017

The PCA(Principal Component Analysis) algorithm is widely used as a technique of expressing the eigenvectors of the covariance matrix that best represents the characteristics of the data and reducing the high dimensional vector to a low dimensional vector. In this paper, we have developed a personal authentication method based on ECG using principal component analysis. The proposed method showed excellent recognition performance of 98.2 [%] when it was experimented using electrocardiogram data obtained at weekly intervals. Therefore, it can be seen that it is useful for personal authentication by reducing the dimension without changing the information on the variability and the correlation set variable existing in the electrocardiogram data by using the principal component analysis technique.

• Journal of Mechanical Science and Technology
• /
• v.14 no.3
• /
• pp.291-297
• /
• 2000

Modern helicopter rotor blades with non-homogeneous cross sections, composed of anisotropic material, require highly sophisticated structural analysis because of various cross sectional geometry and material properties. They may be subjected by the combined axial, bending, and torsional loading, and the dynamic and static behaviors of rotor blades are seriously influenced by the structural coupling under rotating condition. To simplify the analysis procedure using one dimensional beam model, it is necessary to determine the principal coordinate of the rotor blade. In this study, a method for the determination of the principal coordinate including elastic and shear centers is presented, based upon continuum mechanics. The scheme is verified by comparing the results with confirmed experimental results.

• Explosives and Blasting
• /
• v.30 no.1
• /
• pp.1-8
• /
• 2012

In this study, the inner principal stress of concrete blocks caused by an impact load was analyzed with a finite element program, Visual FEA, which was used to model the cross section of the concrete blocks. As a result, it was found that the deviation of the maximum principal stress was varied 2 to 3 times depending on the physical properties of the concrete blocks.

• Korean Journal of Human Ecology
• /
• v.17 no.1
• /
• pp.45-56
• /
• 2008

The purpose of this study was to provide data for the stress and difficulty of the principal on the day-care centers. For this purpose, we had interviewed with 154 principals on the day-care centers in Daejeon and Chungcheong-do. The principals reported that they had stress about administration of day-care center normally. Their stress was different by the type of the center, the number of the class and their sex. They had difficulties in administrating teachers, managing the center, relating with the authorized officials, and finances. For the governing their center expertly, they needed to improve the quality of teachers, to amplify the financial support, and so on.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 2003.10a
• /
• pp.131-134
• /
• 2003

The purpose of this study is for classification to do a short distance rural area with the object to the center to Cheongju area. This study used principal component analysis and geography information system, and it was disciplined oneself. It was done a study object region to Cheongju-si, Cheongwon-gun Goesan-gun, Eumseong-gun, and we divided an index by of 22 large class and 104 small class, and the SPSS analyzed the Principal Component Analysis. We used a Geography Information System, and it was made graphical data by the results that have finished Principal Component Analysis.

• Journal of the Korean Data and Information Science Society
• /
• v.14 no.4
• /
• pp.773-787
• /
• 2003

Principal component analysis, factor analysis and cluster analysis have been performed to analyze the relationship between air pollutants and meteorological variables measured in 1999 in Seoul. In principal analysis, the first principal has been shown the contrast effect between $O_3$ and the other pollutants, the second principal has been shown the contrast effect between CO, $SO_2$, $NO_2$ and $O_3$, PM10, TSP. In factor analysis, the first factor has been found as PM10, TSP, $NO_2$ concentrations which are related with suspended particulates. As a result of cluster analysis, three clusters respectively have represented different air pollution levels, seasonal characteristics of air pollutants and meteorological situations.

• Journal of the Korean Data and Information Science Society
• /
• v.21 no.3
• /
• pp.589-595
• /
• 2010

In discriminant analysis, we consider an intraclass correlation pattern by principal component analysis. We assume that the two populations are equally likely and the costs of misclassification are equal. In this situation, we consider two procedures, i.e., the test and proportion procedures, for selecting the principal components in classifica-tion. We compare the regular classification method and the proposed two procedures. We consider two methods for estimating error rate, i.e., the leave-one-out method and the bootstrap method.

• Bulletin of the Korean Chemical Society
• /
• v.32 no.7
• /
• pp.2332-2338
• /
• 2011

In this study, we proposed a new promising idea of utilizing moving window principal component analysis (MWPCA) as a sensitive diagnostic tool to detect the presence of peak position shift. In this approach, the moving window is constructed from a small data segment along the wavenumber axis. For each window bound by a narrow wavenumber region, separate PCA analysis was applied. Simulated spectra with complex spectral feature variations were analyzed to explore the possibility of MWPCA technique. This MWPCA-based detection of the peak shift, potentially coupled with 2D correlation analysis to provide additional verification, may offer an attractive solution.

• Animal cells and systems
• /
• v.2 no.4
• /
• pp.439-449
• /
• 1998

To discuss the taxonomic dispositions of Korean Isopyroideae (Ranunculaceae) taxa, principal components analysis and cluster analysis were performed using quantitative and qualitative morphological characters. The principal components analysis revealed that the size and number of ovule, ovary width, ratio of style length/ovary length, filament length, sepal size, style length, leaf size, and ovary length are important characters to distinguish Korean Isopyroideae taxa. The cluster and principal components analyses based on both quantitative and quantitative characters demonstrate that lsopyrum mandshuricum is more closely related to Enemion raddeanum than to Semiaquilegia adoxoides. Even though Enemion s not separated from Isopyrum by uantitative characters, they are distinguished by qualitative characters, suggesting that our taxa, Enemion, Semiaquilegia, Isopyrum and Aquilegia, should be recognized in Korean Isopyroideae. In addition, cluster analyses suggest that S. adoxoides could be separated from Aquilegia buergeriana var, oxysepala.

• Proceedings of the Korean Geotechical Society Conference
• /
• 1994.03b
• /
• pp.3-12
• /
• 1994

Based on the shear failure mechanism, hydraulic fracturing criteria are extended to three dimensional stress state. According to the situation of the directions of borehole and major principal stress axes, three equations can be derived for three dimensional hydraulic fracturing problems. By comparing these equations, a single criterion is selected for hydraulic fracturing pressure in cohesive soils. The criterion is a function of maximum principal stress, minimum principal stress and soil parameters in UU conditions. The equation indicates that with any increase in maximim principal stress, hydraulic fracturing pressure decreases. In order to prove the integrity of the criteria, laboratory tests are performed on compacted cubical specimens using true a triaxial apparatus. The shape and direction of fractures are determined by injecting colored water after fracture initiation. It is found that the direction of fractures are perpendicular to the o1 plane.