• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.257-260
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• 2010

The purpose of this paper is to introduce a method to predict the case thermal insulation charred and erosion thickness as a function of the exposure time to combustion gases and in solid rocket motors. The sizing of the insulator requires a good estimation of the thermal and mechanical loads at the wall. The method is particularly suitable for internal insulation areas subjected to high radiative, convective heat fluxes and $Al_2O_3$ slag pool. The mathematical approach and lab-scale experiment were intentionally simplified in order to obtain some simple and rapid relationships particularly useful for trade-off studies and thermal insulation preliminary design. The method was utilized to compute the charred and erosion thicknesses of the insulation on the aft chamber domes. A comparison between theoretical and experimental insulator char thicknesses of the motor insulation is reported, indicating the applicability of the predictive method employed.

• Journal of the Korean Home Economics Association
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• v.41 no.3
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• pp.1-15
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• 2003

This study was conducted to analyze the actual wearing conditions and body fit preferences of the middle-aged women's ready-to-wear lower body clothing. The aim was also to analyze lower body recognition, lower body satisfaction, fit preferences and size satisfaction according to age and degree of girth size. A questionnaire was developed and administered to 300 middle-aged women aged 34 to 59. Statistical tests such as descriptive analysis, crosstabs, and X²-tests were conducted to analyze the data and ascertain the differences between the ages. Lower body satisfaction and recognition were compared by T-test. Also, Anova was used to analyze lower body recognition, satisfaction, fit preferences, and size satisfaction according to age and degrees of girth size. The results indicated that women aged 50 to 59 were more dissatisfied with the ready-to-wear sizing system and because of their body shapes had changed, their need for a larger size range system had also increased. Moreover, the element that most affected their purchase of ready-to-wear lower body clothing was the design followed by the size. The women, especially of the ages 50 to 59, showed a tendency to he dissatisfied with their lower bodies and they recognized that their lower bodies had thickened compared to women aged 34 to 39 and 40 to 49. Analysis of body satisfaction, recognition, and fit preference according to girth size showed that the group of larger girth size recognized that their lower bodies were thicker and were more dissatisfied and preferred looser fittings than the groups of smaller women.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.11
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• pp.925-933
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• 2014

Today, computational fluid dynamics (CFD) is widely used in industry because of the availability of high-performance computers. However, full-scale analysis poses problems owing to the limited resources and time. In this study, the performance and optimal size of a heat exchanger were calculated using the effectiveness-number of transfer units (${\varepsilon}-NTU$) method and a database of characteristics heat exchanger. Information about the geometry and performance of various heat exchangers is collected, and the performance of the heat exchanger is calculated under the given operating conditions. To determine the optimal size of the heat exchanger, a Genetic Algorithm (GA) is used, and MATLAB and REFPROP are used for the calculation.

• Journal of Fashion Business
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• v.25 no.4
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• pp.36-60
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• 2021

This study aimed to provide basic data for establishing a sizing system for menswear by investigating body size changes and body shapes in adult men in their 30s to 50s. Data on 52 different upper body categories collected from 4,314 people during the 5-7th Size Korea surveys were analyzed. The waist height, hip height, torso and arm lengths, and torso and upper limb circumferences increased while the arm joint sizes decreased. According to factor analysis, factors 1 and 2 referred to 'the horizontal size of the upper body and limbs' and the 'torso height and upper limb length', respectively, while factors 3 and 4 represented 'shoulder size' and 'upper body length' respectively. In clustering analysis, types 1 and 2 were 'short and fat' and 'tall and thin,' respectively, while types 3 and 4 represented 'tallest and chubby' and 'shortest and small' respectively. Torso length increased in the 30 to 40s in type 1 while torso circumference increased in the 30s and late 40s in type 2. In type 3, shoulders got bigger in the 30s. In type 4, torso circumference increased in the early 30s, and torso length increased in the late 40s. 'Thin' was a typical body shape in the early 30s. Among early 40s men, distribution evolved from 'small' to 'thin.' In the late 40s, while the percentage of 'small' decreased, the ratio of 'obese' increased. In the 50s, 'small' was the most common.

• Fashion & Textile Research Journal
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• v.21 no.3
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• pp.318-325
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• 2019

This study analyzes current self-nail tips and nail-tip satisfaction. The study method selected from 3 domestic and 3 overseas companies analyzed current self-nail tips based on brand recognition and sales rate. A questionnaire was conducted on 261 adult women in their 20s and 50s about the satisfaction of nail care and self-nail tips. The results are as follows. As a result to analyze the current nail tips, there were products that did not contain the type of nail tip or the composition and ingredients of the glue. An online survey of the sizes of the current nail tips indicated differences in the sizing system method and that the presented sizes are different. The response rate was the highest for the survey results on why self-nail tips were preferred for respondents who prefer self-nail tips because the price was cheap. The reason why they did not prefer self-nail tips was that the degree of completeness was lower and the fitness was not good. In addition, it showed a high response rate in that the adhesive strength was poor and the size did not fit the nails. Therefore, it is necessary to develop a size for nail types by ergonomic design and develop a self-nail tip that can reduce nail damage.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.3
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• pp.93-98
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• 2022

Recently, fast storage media such as Optane have emerged, and memory system configurations designed for disk storage should be reconsidered. In this paper, we analyze the effect of the page size on the memory system performances when fast storage is adopted. Based on this, we design a page size model that can guide an appropriate page size for given workloads in virtualized environments. Configuring different page sizes for various workloads is not an easy matter in traditional systems, but due to the widespread adoption of cloud systems, page sizing performed in our model is feasible for virtual machines, which are generated for executing specific workloads. Simulation experiments under various virtual machine scenarios show that the proposed model improves the memory access time significantly by configuring page sizes for given workloads.

• Journal of the Korea Fashion and Costume Design Association
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• v.16 no.4
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• pp.217-228
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• 2014

The purpose of this study is to grasp inconveniences and improvements by examining wearing condition and satisfaction of protective clothing targeting 114 Korean farmers and to suggest basic data for enhancement of pattern and wearing satisfaction of protective clothing by understanding problems of pesticide-proof clothing through comparative analysis on the size of its commercial products. Most of male subjects were in charge of spraying pesticide, whereas female were most likely to play an assistant role to hold the hose of pesticide applicator. Both of female and male subjects were very aware of the harmful effect of pesticide on human body and tried to take off the clothes immediately after spraying it to reduce possible damage caused by pesticide. As a result of examining wearing condition, the farmers avoided wearing protective clothing because that it feels hot, stuffy, and uncomfortable to move. This hesitant response of wearing the clothing was not shown significantly in case of female subjects who play an assistant role for spraying. Although the farmers wore protective equipments such as mask or gloves in a proper way as compared to protective clothing, they seemed to choose alternative way rather than best way to block pesticide completely. The satisfaction regarding to the fitting of protective clothing which the subjects showed low in all items of upper-lower clothes except waistline. It is necessary to improve the functionality such as relief from heat stress and convenience for movement rather than design or economic in protective clothing development. As a result of comparing the size of five kinds of commercial protective clothing, the farmers got confused to choose the product since designation method of size across companies showed a significant difference in an identical clothing size. In addition, the sizing system developed on a basis of a well-built man has become a hindering factor in wearing satisfaction of female farmers.

• Journal of the Korean Society of Costume
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• v.62 no.8
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• pp.1-18
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• 2012

The purpose of the study was to offer in-depth understanding of the women's wear research trend in South Korea and thus to provide insights from the findings throughout the study to set appropriate directions for further development of women's wear related researches in the clothing and textile study area. The study considered research papers published by the 6 major apparel related journals listed on the KCI(Korea Citation Index) i.e. journals of the Korean Society of Clothing and Textiles(KSCT), the Korean Society of Costume(KSC), the Costume Culture Association (CCA), the Korean Society of Fashion Business(KSFB), the Korean Home Economics Association (KHEA) and the Korean Society for Clothing Industry(KSCI). A total of 380 research papers that were related with women's wear published from 2001 to 2010 were selected for the study and analyzed in the form of descriptive statistics using the SPSS Software ver. 18.0. The analysis was categorized according to the journals, years and research theme. The research themes were divided into various categories such as, clothing construction, textile science, fashion aesthetics and design, costume history and culture, apparel psychology and fashion marketing. The results derived from the research were: (1) the ratio of the research papers on the women's wear to the total papers published from 2001 to 2010 by the 6 subject journals was 380 to 6,815, i.e. 5.6% of the total papers; (2) journal of KSCT published the most women's wear research papers (N=149, 39.2%) and then the rest in order were the journal of CCA (N=69, 18.2%), the journal of KSC (N=68, 17.9%), the journal of KSFB (N=52, 13.7%), the journal of KHEA (N=39, 10.3%) and the journal of KSCI (N=3, 0.7%); (3) the proportions of the research themes for the women's wear study were in the order of the case study in marketing (N=135, 35.5%), body measurements and sizing systems in clothing construction (N=88, 23.2%), fashion design and aesthetics (N=83, 21.8%), pattern-making (N=63, 16.6%), and color study (N=11, 2.9%) and so on.

• Journal of the Korean Society for Railway
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• v.19 no.2
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• pp.262-269
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• 2016

Subway station scales are determined by peak predictions. In this study, the purpose behind the installation of a subway is public transportation convenience and public interest, but economic validity is also important. By proving that the scale of the station is excessive with regard to the target station size for Seoul subway Line 5-8, a reasonable plan. can be sought. According to station installation standards, the area of the station under investigation here is out of the service levels by six stages (A~F), and it must be four or more levels (D). The Actual level for the B level is a two-step design. The Actual ratio for over- Peak predictions is only 17.8% on average. The results of measurements of the excess area and determination of the excessive costs were analyzed by subdividing the area and by calculating it based on the B level, finding that it is possible to provide benefits for customers only in the current design, with an area ratio of 16.3%. Given the weight, it was estimated that current conditions can meet the needs of only 18.6% of the current area. Simplifying the scale calculation method of the station, it is convenient, safe, and advantageous to move citizens only if the scale can be streamlined. Then, with a reduced initial investment, maintenance costs during the operation can be reduced.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.1
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• pp.177-188
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• 2019

The purpose of the optimization of the installation of supply/exhaust ports for tunnels with transverse ventilation system is to supply fresh air from outside to inside of tunnels uniformly and exhaust pollutant from tunnels properly for creating safe and clean environment for tunnel users. For this purpose, a ventilation port area optimization program was developed to obtain a uniform supply or exhaust air volume inside a great depth double deck tunnel with transverse ventilation system. In order to area optimize the developed port sizing program, the wind velocity was measured in the duct of the currently operated tunnel with semi-transverse ventilation. Also 3D cfd was performed on the same tunnel and cfd results were compared to the measured value. As a result, the error rate between the predicted value from the program and measured value was 6.72%, while the error rate between the predicted value from the program and 3D cfd analysis value was 4.86%. Both of comparison results show less than 10% of error rate. Thus It is expected that supply/exhaust port optimization design of transverse ventilation tunnel can be possible with using this large exhaust port area optimization program.