• 한국수산과학회지
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• 제29권3호
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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.

• 대한인간공학회지
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• 제31권1호
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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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• 제8권6호
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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.

• 한국분말재료학회지
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• 제27권1호
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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.

• 한국의류학회지
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• 제30권6호
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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.

• 여성건강간호학회지
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• 제4권3호
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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.

• 융합신호처리학회 학술대회논문집
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• 한국신호처리시스템학회 2005년도 추계학술대회 논문집
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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.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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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.

• 한국식품과학회지
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• 제25권5호
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• pp.541-545
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• 1993

Sieve shaker와 Elzone particle size analyzer에 의한 두 가지 방법으로 제분방법에 따른 입자크기를 조사하였다. 제분방법별로 제조한 쌀가루의 입도분포를 측정한 결과 입자크기는 제분방법에 따라 영향을 받았으며 표준망체를 이용한 Sieve shaker 방법보다 Elzone particle size analyzer를 사용한 방법이 정확도가 우수하였다. 입도분포를 측정한 결과 Pin mill의 경우 $200{\sim}270$mesh가 30.38%으로 가장 많았고 $60{\sim}500mesh$의 분포도를 가졌다. Colloid mill은 $140{\sim}200mesh$가 가장 많았으며, $40{\sim}500mesh$의 분포도를 가졌다. Micro mill은 500mesh 이상이 41.62%로 가장 많았고 $140{\sim}500mesh$의 분포도를 보여주었다. Jet mill은 500 mesh 이상의 분포도로 입자크기가 가장 미세하였다. 또한 미세한 입자일수록 L간과 a값이 증가하였다. 쌀가루의 집합체를 살펴본 결과 습식제분은 분리된 쌀가루의 집합체형태로 구성되어 있고 건식제분은 분활된 조직체로 구성되었다. 전자주사현미경은 Elzone particle size analyzer 방법과 같은 입자분포도를 나타내었고 제분방법에 따라 구조의 특성을 보여주었다.

• 한국융합학회논문지
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• 제11권6호
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• pp.259-268
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• 2020

본 연구는 팬덤활동에 연구들을 총체적·계량적으로 분석한 후 팬덤활동의 구성 유형과 효과를 검증하는 데 목적이 있다. 연구결과는 다음과 같다. 효과크기 비교 시 사회경제분야 관련 변인이 가장 큰 효과크기를 보였고, 다음은 개인 행동, 개인심리로 효과크기가 나타났다. 다음으로 팬덤활동의 영향요인에서 긍정적 변인의 효과크기가 중간 수준의 효과크기를 나타내고 부정적 변인의 효과크기가 낮은 수준의 효과크기를 보이는 것으로 나타났다. 또한 팬덤 형태 내 분석에서는 팬덤이 아이돌 팬덤일 때 가장 효과크기가 크고, 그다음은 스포츠스타, 배우 순이었다. 연구 대상자 중 효과크기는 대학생, 전체, 성인, 중고등학생, 중학생 순으로 나타났다. 한편 나라별 구분에 따른 분석을 실시한 결과 중국이 가장 효과크기가 높고, 유사하게 미국의 경우도 높은 수준의 효과크기가 있었다. 반면 대한민국의 경우 효과크기가 나타나 낮은 수준의 효과크기를 보였다.