• Journal of the Korean Geotechnical Society
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• v.39 no.8
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• pp.17-28
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• 2023

Laboratory-scale hydraulic fracturing experiments were conducted on granite specimens at various viscosities and injection rates of the fracturing fluid. A series of cross-sectional computed tomography (CT) images of fractured specimens was obtained via a three-dimensional X-ray CT imaging method. Pixel-level fracture segmentation of the CT images was conducted using a convolutional neural network (CNN)-based Nested U-Net model structure. Compared with traditional image processing methods, the CNN-based model showed a better performance in the extraction of thin and complex fractures. These extracted fractures extracted were reconstructed in three dimensions and morphologically analyzed based on their fracture volume, aperture, tortuosity, and surface roughness. The fracture volume and aperture increased with the increase in viscosity of the fracturing fluid, while the tortuosity and roughness of the fracture surface decreased. The findings also confirmed the anisotropic tortuosity and roughness of the fracture surface. In this study, a CNN-based model was used to perform accurate fracture segmentation, and quantitative analysis of hydraulic stimulated fractures was conducted successfully.

• Journal of the Korean Society of Radiology
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• v.18 no.3
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• pp.231-237
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• 2024

Brain injury causes persistent disability in survivors, and epidural hematoma(EDH) and subdural hematoma (SDH) resulting from cerebral hemorrhage can be considered one of the major clinical diseases. In this study, we attempted to automatically segment and hematomas due to cerebral hemorrhage in three dimensions based on computed tomography(CT) images. An improved GVF(gradient vector flow) algorithm was implemented for automatic segmentation of hematoma. After calculating and repeating the gradient vector from the image, automatic segmentation was performed and a 3D model was created using the segmentation coordinates. As a result of the experiment, accurate segmentation of the boundaries of the hematoma was successful. The results were found to be good even in border areas and thin hematoma areas, and the intensity, direction of spread, and area of the hematoma could be known in various directions through the 3D model. It is believed that the planar information and 3D model of the cerebral hemorrhage area developed in this study can be used as auxiliary diagnostic data for medical staff.

• Environmental Engineering Research
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• v.19 no.4
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• pp.345-354
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• 2014

In this paper, effects of physical configurations and operating conditions on bubble column performance were analyzed in terms of bubble hydrodynamic and mass transfer parameters. Bubble column with 3 different dimensions and 7 gas diffusers (single / multiple orifice and rigid / flexible orifice) were applied. High speed camera and image analysis program were used for analyzing the bubble hydrodynamic parameters. The local liquid-side mass transfer coefficient ($k_L$) was estimated from the volumetric mass transfer coefficient ($k_La$) and the interfacial area (a), which was deduced from the bubble diameter ($D_B$) and the terminal bubble rising velocity ($U_B$). The result showed that the values of kLa and a increased with the superficial gas velocity (Vg) and the size of bubble column. Influences of gas diffuser physical property (orifice size, thickness and orifice number) can be proven on the generated bubble size and the mass transfer performance in bubble column. Concerning the variation of $k_L$ coefficients with bubble size, 3 zones (Zone A, B and C) can be observed. For Zone A and Zone C, a good agreement between the experimental and the predicted $K_L$ coefficients was obtained (average difference of ${\pm}15%$), whereas the inaccuracy result (of ${\pm}40%$) was found in Zone B. To enhance the high $k_La$ coefficient and absorption efficiency in bubble column, it was unnecessary to generate numerous fine bubbles at high superficial gas velocity since it causes high power consumption with the great decrease of $k_L$ coefficients.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.4
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• pp.197-203
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• 2015

Nuclear power plant has increased continuously for power production in all over the world and the interest about nuclear accident and the dismantling of aging nuclear power plant has been a growing. The leaked radioactive source that is generated by radiation accidents must detect and remove to minimized the damage as soon as possible. Gamma-ray detection system that have been developed until now cannot provide the precise position of radioactive sources because they detect and imaging the position of radiation sources in just two dimensions. In this paper, stereo gamma ray detection system has developed and the algorithm for calculation of the distance has implemented to be able to measure the distribution of the leakage gamma ray source for the system. Stereo camera calibration for distance detection was conducted with the correction pattern and LED light and we carried out performance test of the system for the LED light source and a gamma ray source. In both experiments the results of the performance test, it was confirmed to have a 5% error. The results of this paper is used as a material for the development of gamma-ray imaging device.

• Fashion & Textile Research Journal
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• v.20 no.6
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• pp.656-668
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• 2018

The main object of this study was to understand the body image and body management behavior associated with desiring a thinner and more muscular body. The present study examined whether the drives for thinness and muscularity occur concurrently for both male and female college students, and whether there are gender differences. Moreover, the effects of objectified body consciousness on drive for thinness and drive for muscularity were investigated. A self-administered survey was conducted and a total of 390 data were used for data analysis. Participants included 197 male college students and 193 female students. Results indicated that male students reported significantly lower drive for thinness and higher drive for muscularity than female students. However, the drives for thinness and muscularity were significantly correlated for both male and female college students, and they reported discrepancies between their BMI and self-perceived weight and muscle mass. Findings supported the significant effects of objected body consciousness on the drives for thinness and muscularity for both male and females. Sub-dimensions of objectified body consciousness had differential effects on drive for thinness and muscularity. Specifically, body surveillance and body shame significantly influenced male and female students' drive for thinness, while their control belief did not have significant effects on their drive for thinness. Additionally, body shame emerged as significant unique predictor of drive for muscularity. In terms of gender comparisons, while the effect of body shame was the strongest for the males, the effect of surveillance was as strong as that of body shame for the females.

• Journal of the Korean Home Economics Association
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• v.42 no.11
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• pp.137-150
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• 2004

The purpose of this study was to examine the effect of clothing color and exposure on stereotype formation of female appearance. The subjects for the research survey were 418 male and female university students in Taejon, Korea. The measuring instruments were a self-administered questionnaire and six written scripts which described a woman wearing clothing manipulated by clothing color and exposure variables. The collected data were analyzed using content analysis, T-test, crosstabs analysis, ANOVA, and Duncan's multiple range test. The results of this study were as follows. First, three dimensions (global image, appearance inference, and appearance evaluation) emerged from the subject responses. Clothing exposure had the greatest impact upon the stereotype formation of female appearance. The woman wearing exposed clothing was rated as 'sexy', 'confident', and 'glamorous' whereas the same woman wearing unexposed clothing was rated as 'slim', 'humdrum', 'ladylike', and 'neat'. Second, the gender of the subject played a role in forming stereotypes of women's appearance. The male subjects rated the woman wearing exposed clothing as 'sexy' and 'glamorous' whereas the 1em81e subjects rated the same woman as 'slim' and 'pretty'. Third, the male subjects evaluated the woman wearing expend clothing in much more negative terms than the female subjects did, indicating that men tended to use 'modesty' to evaluate the woman whereas women tended to use 'fashion trend' in addition to 'modesty' as the important criteria when assessing women dressed in exposed clothing. Fourth, the subjects judged the woman wearing exposed clothing to be an entertainer or prostitute in her early 20s. On the other hand, the subjects judged the woman wearing unexposed clothing to be either a university student or a professional business women in her mid 20s.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.7
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• pp.1053-1064
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• 2010

This study investigates the Korean loungewear market and the traditional culture values of consumers related to loungewear to examine the preference of Korean traditional details, sewing techniques in loungewear design, and purchasing intentions. A survey method was used in this study. A total of 230 self-administered questionnaires were obtained from female consumers and 214 data sets were used for analysis. For the analysis, factor analysis, cluster analysis, and ANOVA were executed with PASW Statistics 18.0 and a structural equation model was estimated by Amos 18.0. The results are as follows. Traditional culture values were classified into two dimensions, traditional succession value and traditional design preference value. In the structure equation model, the traditional design preference value had a significant effect on the preference and the traditional culture succession value had significant effect on purchase intention. The results proved that the preference on loungewear with Korean traditional elements is closely related to purchase intention. Consumer groups were divided into three groups by traditional culture values factor; traditional culture succession group, traditional design preference group, and traditional culture indifference group. Style preference images showed significant differences in relation to traditional culture groups. This study is for use as fundamental knowledge on traditional loungewear brand development and strategy planning by offering specific traditional culture aspects associated with preference and purchase intentions.

• Journal of KIISE:Software and Applications
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• v.27 no.4
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• pp.422-431
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• 2000

This paper proposes a new codebook generation method, called a PCA-Based VQ, that incorporates the PCA (Principal Component Analysis) technique into VQ (Vector Quantization) codebook design. The PCA technique reduces the data dimensions by transforming input image vectors into the feature vectors. The cluster of feature vectors in the transformed domain is bisectioned into two subclusters by an optimally chosen partitioning hyperplane. We expedite the searching of the optimal partitioning hyperplane that is the most time consuming process by considering that (1) the optimal partitioning hyperplane is perpendicular to the first principal axis of the feature vectors, (2) it is located on the equilibrium point of the left and right cluster's distortions, and (3) the left and right cluster's distortions can be adjusted incrementally. This principal axis bisectioning is successively performed on the cluster whose difference of distortion between before and after bisection is the maximum among the existing clusters until the total distortion of clusters becomes as small as the desired level. Simulation results show that the proposed PCA-based VQ method is promising because its reconstruction performance is as good as that of the SOFM (Self-Organizing Feature Maps) method and its codebook generation is as fast as that of the K-means method.

• The KIPS Transactions:PartB
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• v.10B no.7
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• pp.837-846
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• 2003

This paper deals with plain figures on the architectural drawings of apartment. This kind of architectural drawings consist of main walls represented by two parallel bold lines, symbols (door, window, $\cdots$), dimension line, extension line, and dimensions represent various numerical values and characters. This paper suggests a method for recognizing main wall which is a backbone of apartment in an architectural drawing. In this thesis, the following modules are realized : an efficient image barbarization, a removal of thin lines, a vectorization of detected lines, a region bounding for main walls, a calculation of extension lines, a finding main walls based on extension line, and a field expansion by searching other main walls which are linked with the detected main walls. Although the windows between main walls are not represented as main walls, a detection module for the windows is considered during the recognition period. So the windows are found as a part of main wall. An experimental result on 9 different architectural drawings shows 96.5% recognition of main walls and windows, which is about 5.8% higher than that of Karl Tombre.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.225-228
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• 2022

The method of calculating the architectural design cost of the Korean Society of Architecture Policy considers the time spent during the design period. Therefore, faster design times can reduce design costs. As a result of a survey of students majoring in architecture, they felt tiredness from repeated floor plan drawings and difficulties in that there were many things to consider when floor plan drawing. In this paper, we implement a program that can automatically convert sketches into standardized floor plans during the architectural design process and a web app for user convenience. In the proposed method, when a user registers a sketch image through a web app, the program separates the space in the drawing through geometric shapes detection. Based on the dimensions and spatial information shown in the sketch, the outer and inner walls are displayed and the appropriate furniture is placed in the space. Through the proposed method, the design cost can be expected to be reduced by reducing the time of the drawing process in the architectural design stage, and 95.2% of architectural students expressed their intention to use the program.