• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.26 no.2
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• pp.121-129
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• 2016

The noise pattern of a household refrigerator is dependent on the characteristics of its operating cycle which is repeated with a specific pattern depending on various parameters, such as room temperature and performance of its mechanical parts. Analysis of noise pattern is essential prior to evaluation of sound quality of a refrigerator. In this study, 14 units of refrigerator were classified into 4 types according to noise pattern and sort of mechanical part, which helps to analyze characteristics of refrigerator noise. Sound quality metrics(loudness, sharpness, roughness, and fluctuation strength) were calculated to compare noise pattern of the 4 types of refrigerator. The results of this study can be useful to decide noise performance of refrigerator.

• Journal of Korean Association for Spatial Structures
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• v.6 no.1 s.19
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• pp.117-127
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• 2006

Membrane structures, a kind of lightweight soft structural system, are used for spatial structures. The design procedure of membrane structures are needed to do shape finding, stress-deformation analysis and cutting pattern generation, because the material property has strong axial stiffness, but little bending stiffness. The problem of cooing pattern is highly varied in their size, curvature and material stiffness. So, the approximation inherent in cutting pattern generation methods is quite different. Therefore the ordinary computer software of structural analysis & design is not suitable for membrane structures. In this study, we develop the program for cooing pattern generation using geodesic line, and investigate the result of example's cooing pattern in detail.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.2
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• pp.111-119
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• 2013

Face recognition has recently become one of the most popular research areas in the fields of computer vision, machine learning, and pattern recognition because it spans numerous applications, such as access control, surveillance, security, credit-card verification, and criminal identification. In this paper, we propose a simple descriptor called an ECSP(Extended Center-Symmetric Pattern) for illumination-robust face recognition. The ECSP operator encodes the texture information of a local face region by emphasizing diagonal components of a previous CS-LBP(Center-Symmetric Local Binary Pattern). Here, the diagonal components are emphasized because facial textures along the diagonal direction contain much more information than those of other directions. The facial texture information of the ECSP operator is then used as the input image of an image covariance-based feature extraction algorithm such as 2D-PCA(Two-Dimensional Principal Component Analysis). Performance evaluation of the proposed approach was carried out using various binary pattern operators and recognition algorithms on the Yale B database. The experimental results demonstrated that the proposed approach achieved better recognition accuracy than other approaches, and we confirmed that the proposed approach is effective against illumination variation.

• Progress in Superconductivity
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• v.6 no.2
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• pp.113-117
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• 2005

In this study, electromagnetic analysis of current paths including meander pattern, spiral pattern, and bi-spiral pattern were performed and in order to verity the analysis results, experiments tests including quench test, and insulation tests were performed. In addition, bubble corner concepts were introduced to enhance insulation reliability. From our study, bi-spiral pattern of YBCO thin films were rather effective for quench and insulation than the other patterns. So this current path pattern was adopted for YBCO thin films in order to develop 6.6 kV resistive fault current limiters. Finally YBCO thin films were connected in series and parallel to enhance capacity, and the test results of current limiting characteristics of 6.6kV resistive SFCL were successful. The Progress in Superconductivity is published every six month and serves as a channel for publications on superconductivity and related topics. The author(s) are required to submit THREE copies of the manuscripts along with original figures directly to the Editor.

• Journal of Electrical Engineering and Technology
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• v.9 no.1
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• pp.293-300
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• 2014

This paper proposes a novel pattern recognition approach based on the radial basis function (RBF) neural network for identifying insulation defects of high-voltage electrical apparatus arising from partial discharge (PD). Pattern recognition of PD is used for identifying defects causing the PD, such as internal discharge, external discharge, corona, etc. This information is vital for estimating the harmfulness of the discharge in the insulation. Since an insulation defect, such as one resulting from PD, would have a corresponding particular pattern, pattern recognition of PD is significant means to discriminate insulation conditions of high-voltage electrical apparatus. To verify the proposed approach, experiments were conducted to demonstrate the field-test PD pattern recognition of cast resin current transformer (CRCT) models. These tests used artificial defects created in order to produce the common PD activities of CRCTs by using feature vectors of field-test PD patterns. The significant features are extracted by using nonlinear principal component analysis (NLPCA) method. The experimental data are found to be in close agreement with the recognized data. The test results show that the proposed approach is efficient and reliable.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.9
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• pp.77-88
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• 2019

This study started with the aim of creating a parenting environment for raising children as a solution to the problem of low fertility. Communal housing is a type of housing where professional childcare environment and lives of family with children can be achieved in community space. It is an environment that supports the development of the child and life of family. However, there is no guidance system for planning such an environment. Therefore, this study aims to develop a pattern language for communal housing of families with children. The research method comes in two steps. First, the documents that provided pattern language and design guidelines about the environment of child and families with children were analyzed. Second, experts specialized in child education, women and family, environmental design were interviewed. As a result of analysis of characteristics of derived pattern language, convenience, safe feeling, comfortability in residential unit, movement, safe feeling, convenience in intermediate space convenience, safe feeling, control in community space were high. The pattern language of this study grafted the items that have proven to be important over a long period of time and the environmental design concepts for families with children in the community space. So it enabled differentiation from existing pattern language or design guidelines.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.259-266
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• 2010

Forest fire occurrence in Korea is highly related to human activities and its spatial distribution shows a strong spatial dependency with cluster pattern. In this study, we analyzed spatial distribution pattern of forest fire with point pattern analysis considering spatial dependency. Distributional pattern was derived from Ripley's K-function according to causes and distances. Spatially clustered intensity was found out using Kernel intensity estimation. As a result, forest fires in Korea show clustered pattern, although the degrees of clustering for each cause are different. Furthermore, spatial clustering pattern can be classified into two groups in terms of degrees of clustering and distance. The first group shows the national-wide cluster pattern related to the human activity near forests, such as human-induced accidental fire in mountain and field incineration. Another group shows localized cluster pattern which is clustered within a short distance. It is associated with the smoker fire, arson, accidental by children. The range of localized clustering was 30 km. Beyond of this range, the patterns of forest fire became random distribution gradually. Kernel intensity analysis showed that the latter group, which have localized cluster pattern, was occurred in near Seoul with high densed population.

• Journal of the Korea Fashion and Costume Design Association
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• v.18 no.2
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• pp.101-113
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• 2016

This study was conducted in order to analyze draping and flat pattern according to jacket design, and provide basic materials for developing a jacket pattern that can enhance fitness, functionality, and aesthetic expression of clothes by reflecting esthetic expression of draping and efficiency of flat pattern at the same time. For the experimental jacket designs of a one-piece sleeve jacket and a two-piece sleeve jacket were selected among the entries of the designer Rubina for 2014 F/W Seoul Fashion Week. Designer brand Rubina usually produced clothes using draping and the designer brand company provided the experimental patterns for the study. We also had flat patterns of the same design and size specifications designed by a flat patternmaker who has 30 year-experience in flat pattern like Rubina. The test apparel jacket was made of 20's cotton yarns. Three models wore the jackets and evaluation on appearance fitness was conducted by 7 members in an expert panel group from August 10, 2015 to September 10, 2015. As a result of appearance fitness analysis on one-piece sleeve jacket, there were significant difference in 4 items among 17 items in terms of overall appearance. The appearance of jackets by draping had higher score than those using flat pattern. As for two-piece sleeve jacket, there were significant differences in 7 items among 17 items related to overall appearance. As for the items related to sleeve, 5 items out of 13 showed significant differences. Except for one item, appearance of jackets using draping had higher score than flat pattern. As for motion fitness, draping was evaluated to be more comfortable. Applying the items with high scores in appearance and motion fitness in draping to flat pattern, The study suggests a new jacket pattern development that would increase the satisfaction of consumers for future research.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.76-79
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• 2012

Purpose: This study was to evaluate usefulness of $^{99m}Tc$-MIBI scintimammography for dense breast by comparing concordance in test results between Tc-99m MIBI scintimammography and mammography whose effect was proved the most as an imaging tool depending on breast density and at the same time by examining limitation on evaluation depending on density of breast tissue. [Materials and Methods] In the period from December 2010 to July 2011, this study targeted 150 patients who took both of $^{99m}Tc$-MIBI scintimammography and mammography conducted by using breast gamma camera in this hospital. Breast density was classified to the four levels of pattern 1~4 based on the results of mammography. $^{99m}Tc$-MIBI scintimammography was conducted with the LCC, the RCC, the LMLO, and the RML one minute after intravenous injection of 99mTc-MIBI 7400 MBq (20 mCi) while analysis was made for concordance in test results of $^{99m}Tc$-MIBI scintimammography and mammography. [Results] Among the 150 patients, pattern 1 was found in 3 patients, pattern 2 in 44 patients, pattern 3 in 61 patients, and pattern 4 in 37 patients. There were 5 patients who showed the case where it was impossible to determine density of breast tissue due to foreign body inserted to breast. The concordance ratio of the results between $^{99m}Tc$-MIBI scintimammography and mammography was 95.5% for pattern 2, 95.1% for pattern 3 and 94.6% for pattern 4. This demonstrated that the concordance rate decreased according to the increase in breast density. [Conclusion] When there was limitation on evaluation of breast specific gamma imaging test results due to increased intake in breast tissue or surgical site, the concordance rate was 6.8% for pattern 2, 16.3% for pattern 3 and 18.9% for pattern 4. This demonstrated that the degree of limitation on evaluation of breast specific gamma imaging test results increased according to the increase in breast density.

• Journal of Physiology & Pathology in Korean Medicine
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• v.34 no.1
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• pp.30-36
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• 2020

This study aimed to investigate heart rate variability (HRV) characteristics of cold pattern with repeated measurement data. Participants were taken from a Daejeon University cohort study from 2015 to 2018. Forty-seven of the participants studied displayed cold pattern while 23 showed signs of non-cold pattern. HRV was measured in supine position for 5 minutes at each year, and an 8-item cold pattern questionnaire was used for the diagnosis of cold pattern. SDNN (standard deviation of the NN intervals) and RMSSD (the square root of the mean squared differences of successive NN intervals) were used as time domain analysis, and TP (total power), VLF (power in very low frequency range), LF (power in low frequency range), HF (power in high frequency range), LF norm (LF power in normalized units), HF norm (HF power in normalized units) and LF/HF were used as frequency domain analysis. In the Mann-Whitney U test, LF norm, HF norm, and LF/HF showed differences between the cold pattern group and non-cold pattern group at every measurement, and in the independent t-test, the differences were also observed at three points except for the baseline (2015). In the repeated measures ANOVA, the interaction effects were not observed in all HRV parameters, but the time period effects were observed in SDNN, RMSSD, TP, VLF, LF and HF. There were significant differences between those two groups in LF norm, HF norm and LF/HF. This study suggests that LF norm, HF norm and LF/HF might be a useful indicator of cold pattern properties.