• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.386-392
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• 1996

A numerical method based on genetic algorithms was introduced to characterize the grain-size distribution more effectively. This technique was proved significant particularly for multimodal size distributions, as was verified for samples from Korea Strait continental shelf. Sediment samples collected from the Korea Strait continental shelf revealed that $96\%$ of the grain-size distributions were multimodal. Therefore, the use of grain-size parameters was not the ideal method. As an alternative method, the decomposition of sue curves into elementary normal component curves was used. Means and standard deviations of 593 decomposed normal components were calculated by a numerical method from 268 size curves of Korea Strait sediments. The mean values of decomposed normal components showed peaks at $1\~3\phi\;and\;7\~9\phi$ size classes. The plot of mean and standard deviation values of the coarse fraction normal components on the map showed a characteristic areal distribution. The characteristic distribution was found to derive from underlying Pleistocene sediment on the basis of sea bottom geologic distribution of the area. The method of decomposition into normal components was found to be more effective than the analysis using traditional grain-size parameters in investigation of multimodal size distribution of Korea Strait shelf sediment.

• Journal of the Ergonomics Society of Korea
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• v.31 no.1
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• pp.237-245
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• 2012

Objective: The aim of the study is to analyze female adult's body shape characteristics and to provide the basic information for clothing manufacturing. Background: The comparative study among the age groups is very fundamental to understand the body characteristics of each subjects group. Therefore, comparison of body measurements in age groups was applied in this study. Method: The study was fulfilled by the comparison between the data of the $5^{th}$ Anthropometry of Size Korea (2004) and the $6^{th}$ Anthropometry of Size Korea(2010). The subjects were 2,213 female adults aged 20~59 of the 5th Size Korea anthropometric survey and 2,025 female adults aged 20~59 of the 6th Size Korea anthropometric survey. Results: The differences indicated the decreased values in widths, depths, girths regarding the torso region and BMI. "Head height to Stature ratio" decreased significantly in the 6th data, on the other hand, "Crotch height to Stature ratio" increased in the 6th data. Through the distribution characteristic of the age groups by Stature groups, it was convinced that 160cm stature group is the most frequent among all age groups of the 6th Size Korea. Conclusion: As a summary, the meaningful differences were showed between the 5th anthropometric data and the 6th data. According to the 6th Size Korea, the distribution tendency of obesity is very similar to the 5th Size Korea data. But the percentage of obese women declined significantly. Application: These findings from the study can be utilized women's wear design and construction that reflect body characteristics.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.6
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• pp.2139-2151
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• 2014

Embedded system testing, especially long-term reliability testing, of flash memory solutions such as embedded multi-media card, secure digital card and solid-state drive involves strategic decision making related to test sample size to achieve high test coverage. The test sample size is the number of flash memory devices used in a test. Earlier, there were physical limitations on the testing period and the number of test devices that could be used. Hence, decisions regarding the sample size depended on the experience of human testers owing to the absence of well-defined standards. Moreover, a lack of understanding of the importance of the sample size resulted in field defects due to unexpected user scenarios. In worst cases, users finally detected these defects after several years. In this paper, we propose that a large number of potential field defects can be detected if an adequately large test sample size is used to target weak features during long-term reliability testing of flash memory solutions. In general, a larger test sample size yields better results. However, owing to the limited availability of physical resources, there is a limit on the test sample size that can be used. In this paper, we address this problem by proposing a self-adaptive reliability testing scheme to decide the sample size for effective long-term reliability testing.

• Journal of Powder Materials
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• v.27 no.1
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• pp.44-51
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• 2020

Powder characteristics, such as density, size, shape, thermal properties, and surface area, are of significant importance in the powder bed fusion (PBF) process. The powder required is exclusive for an efficient PBF process. In this study, the particle size distribution suitable for the powder bed fusion process was derived by modeling the PBF product using simulation software (GeoDict). The modeling was carried out by layering sintered powder with a large particle size distribution, with 50 ㎛ being the largest particle size. The results of the simulation showed that the porosity decreased when the mean particle size of the powder was reduced or the standard deviation increased. The particle size distribution of prepared titanium powder by the atomization process was also studied. This study is expected to offer direction for studies related to powder production for additive manufacturing.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.6 s.154
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• pp.892-903
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• 2006

This study was to carry out interview and survey of currently marketed foundation garment, focusing on manufacturers, on the basis of data of Year 2004 SIZE KOREA in 2004, to re-establish suitable age range and standard size, to simplify size interval scale and size system and to revise the standard for consumers' easy understanding and availability; The findings of this study are as follows. 1. Considering the age, in which a bra is worn, has reduced socially, the applicable age range was expanded into $8{\sim}80$ years old, which was divided into for junior and for adult. 2. For bra size, the standard title changed into the foundation garments size standard, in which girdle and bodysuit were included. 3. Basic physical parts for establishing for bra size are underbust and bust. Interval scale of under bust and bust was 5cm and 2.5cm, respectively. And basic physical parts are waist and hip girth for girdle, and underbust, bust, and hip girth for bodysuit. 4. For bra size, underbust girth was applied together with bra-cup size without 'cm' unit. For bra-cup size, difference between underbust and bust was represented as English alphabet. In other words, AAA means that difference between under bust and bust is 5cm. AA, A, B, C and D means that the difference are 7.5cm, 10cm, 12.5cm, 15cm and 17.5cm. 5. For girdle size, waist girth was applied together with hip girth without 'cm' unit. And for bodysuit size, underbust girth was applied together with cup size like bra size, and English alphabet represented hip girth range.

• Women's Health Nursing
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• v.4 no.3
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• pp.375-387
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• 1998

In clinical trials of nursing research, the sample size determination is one of the most important factor. Although sample size must be considered at the design stage, it has been disregarded in most clinical trials. The power analysis is usually performed before study begins to compute sample size and the power can also be calculated at the end of study in order to justify study result. The power analysis is essential especially when the clinical trials can not show significant differences. In this paper, we review the statistical methods for power analysis and sample size formulae in nursing research. Sample size formulae and the corresponding examples are discussed according to the six types of studies ; mean for one sample, proportion for one sample, means in two samples, proportions in two samples, correlation coefficient and ANOVA.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2005.11a
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• pp.317-320
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• 2005

기존의 블라인드 등화(blind equalization) 알고리즘의 step-size는 임의의 값을 알고리즘에 적용하여 수렴속도와 정상 상태의 특성을 고려하여 최적한 step-size를 결정하였다. step-size를 크게 하면 수렴속도는 빠른 반면에 정상 상태에서 에러가 크고, step-size를 작게 하면 수렴속도는 느린 반면에 정상 상태에서 에러가 작아진다. 그렇기 때문에 수렴속도와 정상 상태를 고려해서 step-size를 결정해야 되고, 특별하게 정해지는 기준이 없기 때문에 연구자의 판단에 의해서 다르게 선택된다. 본 논문에서는 등화기 출력의 잔류 심벌간 간섭에 따라 step-size를 가변함으로서 수렴속도 및 정상 상태 성능을 개선한 가변 step-size를 갖는 블라인드 등화 알고리즘을 제안한다.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.479-484
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• 2006

The pore structures of paper were modified by the application of the blending of pulp, refining, and filler particle size and ash content. It was conformed that the reflectivity of paper can be modified by the combination of above parameters. It was also found that the modifications of reflectivity of paper were very close relation with pore structure, such as average pore size, pore size distribution and porosity. The average pore size was decreased with addition of HwBKP, but showed smaller particle size than those made from 100% HwBKP. Refining of pulp decreased both average pore size and the reflectivity of paper. The pore size distribution of filled paper can be varied by the combination of filler particle size and ash content.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.541-545
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• 1993

Two different methods (Sieve shaker, Elzone particle size analyzer) were used to investigate rice flour particle size obtained by various milling method. Results of Elzone particle size analyzer were more effective than Sieve shaker in determining particle size, and the distribution of particle size of rice flours was affected by the type of the milling methods used. A rice flour, prepared in a Pin mill had a particle size range of $60{\sim}500$ mesh, and 30.38% of the sample was in the particle size range $200{\sim}270$ mesh. A rice flour, prepared in a Colloid mill had a particle size range of $40{\sim}500$ mesh and more of flour particles appeared in the range $140{\sim}200$ mesh than any other particle size. A rice flour, prepared in a Micro mill had a particle size range of $140{\sim}500$ mesh, and 41.62% of the sample was in the particle size range over 500 mesh. A rife flour, prepared in a Jet mill had a finer flour particle size was over the particle size range 500 mesh. The finer rice flour gave the highest L value and the lowest a value. The wet-milled flour particles were observed as a cluster of starch granules and the particles of rice flour (dry-milling) were observed as fragment of rice grains. Scanning Electron Photomicrographs revealed that visual differences in structure between milling methods, and similar results with Elzone particle size analyzer method in particle size.

• Journal of the Korea Convergence Society
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• v.11 no.6
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• pp.259-268
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• 2020

The purpose of our study is to conduct a general·quantitative analysis of fandom activities and verify their organization types and effects. The results are as follows. With regard to the comparison of effect size, the variable related to the social and economic field showed the greatest effect size, which was followed by individual behavior and individual mentality. In terms of influential factors of fandom activities, the effect size of positive variables was intermediate level while the effect size of negative variables was low level. In addition, the effect size of fandom supporting idol groups was the greatest, which was followed by of fandoms supporting sports stars, and actors. In terms of the effect size with regard to the influence on fandom among the objects of study, the effect size of university students was the greatest, which was followed by the whole, adult, middle and high school student, and middle school student. Meanwhile, the result of the analysis according to the classification by country showed that China had the greatest effect size, and the US also showed quite a big effect size. On the other hand, South Korea showed a low level of effect size.