• The Korean Journal of Applied Statistics
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• v.34 no.2
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• pp.127-139
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• 2021

Independent Component Analysis is a popular statistical method to separate independent signals from the mixed data, and Group Independent Component Analysis is an its multi-subject extension of Independent Component Analysis. It has been applied Functional Magnetic Resonance Imaging data and provides promising results. However, classical Group Independent Component Analysis works poorly when outliers exist on data which is frequently occurred in Magnetic Resonance Imaging scanning. In this study, we propose a robust version of the Group Independent Component Analysis based on ROBPCA. Through the numerical studies, we compare proposed method to the conventional method, and verify the robustness of the proposed method.

• Journal of Korea Multimedia Society
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• v.24 no.4
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• pp.583-592
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• 2021

Obsessive-compulsive disorder (OCD) is a mental disorder in which a person repeated a particular thought or feels. The domain of beliefs and guilt predicted OCD symptoms. Although there were some neuroimaging studies investigating OCD symptoms, resting-state functional magnetic resonance imaging (rs-fMRI) study investigating intra-network functional connectivity associated with guilt for OCD is not reported yet. Therefore, in the current study, we assessed the differences between intra-network functional connectivity of healthy control group and OCD group using independent component analysis (ICA) method. In addition, we also aimed to investigate the correlation between changed functional connectivity and guilt score in OCD. Total 86 participants, which consisted of 42 healthy control volunteers and 44 OCD patients, acquired rs-fMRI data using the 3T MRI. After preprocessing the fMRI data, a functional connectivity was used for group independent component analysis. The results showed that OCD patients had higher score in emotion state in beliefs and lower functional connectivity in fronto-parietal network (FPN) than control group. A decrease of functional connectivity in FPN was negatively correlated with feelings of guilt in OCD. Our results suggest excessive increase in guilt negatively affect to process emotional state and behavior or cognitive processing by influencing intrinsic brain activity.

• Analytical Science and Technology
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• v.20 no.6
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• pp.502-507
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• 2007

X-ray diffraction method has been widely used for qualitative and quantitative analysis of a mixture of materials since every crystalline material gives a unique X-ray diffraction pattern independently of others, with the intensity of each pattern proportional to that material's concentration in a mixture. For determination of mixing ratios, extracting source spectra correctly is important and crucial. Based on the source spectra extracted, a regression model with non-negativity constraint is applied for determining mixing ratios. In some mixtures, however, X-ray diffraction spectrum has sharp and narrow peaks, which may result in partial negative source spectrum from independent component analysis. We propose several procedures of extracting non-negative source spectra and determining mixing ratios. The proposed method is validated with experimental data on powder mixtures.

• Journal of Oriental Neuropsychiatry
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• v.23 no.3
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• pp.47-62
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• 2012

Objectives : This study is to figure the relations of the heart rate variability, body component analysis and accompanying symptoms of 350 insomnia patients. Methods : For this study we evaluated Heart Rate Variability(HRV) and body component analysis on 350 insomnia patients who visited Dongeui oriental hospital of Dongeui university from January 2008 to March 2012. The accompanying symptoms was collected based on each patient's progress note. Results : 1. There was no difference between PR, LF and VLF of male and female groups. HF was higher in the patients' of female group and LF/HF ratio was higher in the male group. The patients' group of age under 39 had higher HF, LF, VLF and LF/HF ratio than the group over 39. 2. The average of LF was the smallest, and the average of VLF was in the middle, while the average of HF was the largest. 3. Regarding patients' age and gender, as the patients' age increased, their HF, LF, VLF and LF/HF ratio decreased significantly. HF, LF, VLF, and LF/HF ratios were, however, independent on the patients' gender. As the patients' age increased, their BMI increased, while the patients' gender did not affect on their BMI. The amount of visceral fat increased with the patients' age, but wasn't dependent on the patients' gender. 4. As the patients' BMI increased, PR and LF decreased. As the patients' amount of visceral fat increased, PR, HF, LF and VLF decreased. 5. The most frequent accompanying symptoms of the insomnia patients was headache. Neither HF nor LF/HF ratio was dependant on any of the accompanying symptoms. Patients with anxiety showed significantly higher LF than those without anxiety. Patients with fatigue and physical pain showed significantly higher VLF than those without either of them. Conclusions : The study showed that as the insomnia patients age increased, the HF, LF, VLF, LF/HF ratio significantly decreased, but the BMI and visceral fat increased. The HF, LF, VLF, LF/HF ratio BMI, or the visceral fat was independent on the gender. As BMI increased, PR and LF decreased. As visceral fat increased, PR HF, LF and VLF decreased. Patients presenting anxiety had higher LF. Patients either with fatigue or physical pain had higher VLF. Neither HF nor LF/HF ratio had any significant correlation with any of the accompanying symptoms.

• Archives of Pharmacal Research
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• v.14 no.1
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• pp.1-6
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• 1991

The crystal structure of licarin-B, a component of Myristicae Semen was determined by single crystal X-ray diffraction analysis. Crystal of the compound, which was recrystallized from the mixture of hexane and ether, is monoclinic with a=12.740(1), b=7.219(1), c=9.284(1) ${\AA}$, ${\beta}=94.75(1)^{\circ}$, $D_x=1.26$, $D_m=1.27\;g/cm^3$, space group P21, and Z=2. The structure was solved by direct method and refined by least-squares procedure to the final R value of 0.040 for 1532 independent reflections ${F{\ge}3{\sigma}(F)}$. The compound is a dimeric phenylpropanoid, and belongs to the neolignan analogues. The molecules are arranged along with the screw axis. The intermolecular contacts appear to be the normal van der Waals' forces.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1171-1176
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• 1996

The changes in volatiles of the model system were analyzed by GC and GC-MS before and after retorting. The GC data were analyzed statistically by applying the analysis of variance, and 42 peaks were selected at 5% significance level. Multivariate statistical analysis was performed with these 42 peaks as independent variables. Through the stepwise discriminant analysis, 8 peaks, which corresponded to the compounds such as 2-heptanone, cis-3-hexenal, 2-pentyl-furan, 1-methyl-trans-1,2-cyclohexanediol, 2-hexanone, 3-octanone, trans, trans-nona-2,4-dienal and 1-octen-3-ol, were obtained in sequence to distinguish the samples with and without retorting. The principal component analysis of a set of 8 independent variables resulted in 3 principal components which accounted for 96.1% of the variance, while the first principal component (PC 1) explained 76.5% of the total variance. In addition, through the factor analysis of the principal components, the peaks 11, 20 and 21 could be grouped togather in accordance with the direction and the size while the peaks 9, 33 and 39 constituted the second group in the direction.

• Journal of the Korea Safety Management & Science
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• v.14 no.1
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• pp.75-85
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• 2012

In this study, the representative hand shapes for the adult Koreans were analyzed by factor analysis and cluster analyses. The analyses were conducted on the anthropometric data of 58 hand dimensions from 325 subjects having nonhomogeneous demographics. Maximum hand circumference, first phalanx length of index finger, and ratio between the two measures were the independent variables for the cluster analyses. The results of the study showed that Korean hand shapes can be divided into 2 clusters irrespective of their size for each of the male and female group. There were slight differences in component ratio of hand shapes with respect to the occupation and the age, but their differences were not statistically significant. The representative Korean hand shapes and their anthrpometric dimensions could be used to design and establish proper sizing system for various hand operating devices.

• Journal of international Conference on Electrical Machines and Systems
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• v.3 no.1
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• pp.78-82
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• 2014

Power Transformers with more than one secondary winding are not uncommon in industrial applications. But new classes of applications where very large number of independent secondaries are used are becoming popular in controlled converters for medium and high voltage applications. Cascade H-bridge medium voltage drives and Pulse Step Modulation (PSM) based high voltage power supplies are such applications. Regulated high voltage power supplies (Fig. 1) with 35-100 kV, 5-10 MW output range with very fast dynamics (${\mu}S$ order) uses such transformers. Such power supplies are widely used in fusion research. Here series connection of isolated voltage sources with conventional switching semiconductor devices is achieved by large number of separate transformers or by single unit of multi-secondary transformer. Naturally, a transformer having numbers of secondary windings (~40) on single core is the preferred solution due to space and cost considerations. For design and simulation analysis of such a power supply, the model of a multi-secondary transformer poses special problem to any circuit analysis software as many simulation softwares provide transformer models with limited number (3-6) of secondary windings. Multi-Secondary transformer models with 3 different schemes are available. A comparison of test results from a practical Multi-secondary transformer with a simulation model using magnetic component is found to describe the behavior closer to observed test results. Earlier models assumed magnetising inductance in a linear loss less core model although in actual it is saturable core made-up of CRGO steel laminations. This article discusses a more detailed representation of flux coupled magnetic model with saturable core properties to simulate actual transformers very close to its observed parameters in test and actual usage.

• KIPS Transactions on Software and Data Engineering
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• v.11 no.1
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• pp.41-50
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• 2022

In this paper, a method to directly calculate the major elements of skin color such as melanin and hemoglobin from the RGB signal of the camera is proposed. The main elements of skin color typically measure spectral reflectance using specific equipment, and reconfigure the values at some wavelengths of the measured light. The values calculated by this method include such things as melanin index and erythema index, and require special equipment such as a spectral reflectance measuring device or a multi-spectral camera. It is difficult to find a direct calculation method for such component elements from a general digital camera, and a method of indirectly calculating the concentration of melanin and hemoglobin using independent component analysis has been proposed. This method targets a region of a certain RGB image, extracts characteristic vectors of melanin and hemoglobin, and calculates the concentration in a manner similar to that of Principal Component Analysis. The disadvantage of this method is that it is difficult to directly calculate the pixel unit because a group of pixels in a certain area is used as an input, and since the extracted feature vector is implemented by an optimization method, it tends to be calculated with a different value each time it is executed. The final calculation is determined in the form of an image representing the components of melanin and hemoglobin by converting it back to the RGB coordinate system without using the feature vector itself. In order to improve the disadvantages of this method, the proposed method is to calculate the component values of melanin and hemoglobin in a feature space rather than an RGB coordinate system using a feature vector, and calculate the spectral reflectance corresponding to the skin color using a general digital camera. Methods and methods of calculating detailed components constituting skin pigments such as melanin, oxidized hemoglobin, deoxidized hemoglobin, and carotenoid using spectral reflectance. The proposed method does not require special equipment such as a spectral reflectance measuring device or a multi-spectral camera, and unlike the existing method, direct calculation of the pixel unit is possible, and the same characteristics can be obtained even in repeated execution. The standard diviation of density for melanin and hemoglobin of proposed method was 15% compared to conventional and therefore gives 6 times stable.

• Journal of the Korean Society of Costume
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• v.55 no.1 s.91
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• pp.86-100
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• 2005

The purpose of this study was to investigate lifestyle of male college students and their preference of casual wear style. A questionnaire consisted of 60 lifestyle items, 1 casual wear style-preference question and demographic variables was developed. Data were collected from questionnaires distributed to male college students of 7 universities located in the Daegu${\cdot}$Gyeongbuk area during August 2003. After eliminating incomplete questionnaires, 303 were analyzed by descriptive statistics, factor analysis, cluster analysis, one-way ANOVA, and $x^2-test$. As a result of factor analysis on lifestyle items, 8 factors were determined: consumption and fashion orientation, future preparation, social concern, a wide range of thought and experience, health orientation, independent spirit, masculinity, and family orientation. 4 groups were identified on the basis of these 8 factors and named as active pragmatic group, liberal empirical group, prospective self-supporting group, and social accommodative group. Their component ratio were $30.2\%,\;33.2\%,\;19.6\%,\;and\;16.9\%$ respectively. The most preferred casual wear style by male college students was determined as basic casual wear, followed by adult casual wear, fashionable casual wear, and sporty casual wear. Other than the most preferred style, basic casual wear, by every group, the preference of casual wear styles differed among 4 lifestyle groups.