• 한국입자에어로졸학회지
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• 제8권1호
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• pp.1-8
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• 2012

In this study, the collection efficiency of inertial impactors was numerically simulated by employing the statistical Lagrangian particle tracking(SLPT) model. The SLPT model was proven to be correct in predicting the impactor collection efficiency, when the numerically obtained collection efficiencies were compared with the experimental data of Marple et al.(1987) at normal pressure level and the experimental data of $Marjam{\ddot{a}}ki$ et al.(2000) at low pressure level. Based on the validation results, balloon-borne impactors with the cut-off sizes of $1{\mu}m$, $2.5{\mu}m$, and $10{\mu}m$ were designed. Then, the sampling flowrates of the inertial impactors, required to keep the cut-off sizes constant at different pressures and temperatures, were estimated according to the altitude.

• Communications for Statistical Applications and Methods
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• 제8권1호
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• pp.51-63
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• 2001

We are interested in the conditional independence in sparse $2\tims2\tims$K tables with very rare cell counts. The most popular test is Cochran-Mantel-Haenszel statistic when sample sizes are moderately large enough to guarantee the chi-square approximation. We will consider jackknifing the CMH test and also suggest an approximate normal distribution for the standardized jackknifed CMH statistic. The main focus of this paper is to improve the chi-squared approximation to the CMH test by using the asymptotic normality of the jackknifed CMH test when sample sizes are very sparse but K and N$\infty$. The performance of the proposed jackknifed test, in the sense of significance level control and power, will be compared with that of the CMH test through a Monte Carlo study.

• 패션비즈니스
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• 제3권4호
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• pp.131-138
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• 1999

The purpose of this study is to measure Korean, Chinese and Chosunjok college women's body part sizes, and then, classify their body shapes according to the drop value(hip circumference-chest circumference) as well as their statures, and thereupon, comparatively analyze the statistical distribution of their major body part measurements and thereby, provide for some basic data useful to the development of quality fitting apparels exportable to China. The results of this study can be summarized as follows; Most of Korean and Chinese college women were found to belong to the body type of "N" body shape, while many of Chosunjok college women belonged to "H" body shape body type characterized by normal stature but small difference between hip and chest circumferences. The most prevailing body type of Korean and Chinese college women next to "N" type(65%, 51%) was "H" (23%, 35%), followed by "A" type(12%, 14%), while that of Chosunjok college women was "H" type (54%), followed by "N" (40%) and "A" type (6%). On the other hand, in terms of distribution of major body part sizes, there was found a wide difference between Chinese and Korean college women. Chosunjok college women had similar body part sizes to Korean college women's in such measurements as waist back length, shoulder-to-shoulder length, front interscye length, back interscye length, under-chest circumference and weight, while having simliar body part sizes to Chinese college women's in such measures as stature, arm length, waist front length, waist side-hip line length, crotch length, head circumference, neck-root circumference and waist circumference.

• Journal of Nutrition and Health
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• 제55권6호
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• pp.699-708
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• 2022

Purpose: Adequate nutrition is to be provided for normal growth and development during early childhood. Currently, childcare teachers provide lunch to most children in Korea. The purpose of this study was to investigate the portion size provided by teachers and examine the effect of education on food serving size. Methods: The subjects were childcare teachers (n = 120) in charge of children aged 3-5 years at a daycare center in Hanam-si. The survey was conducted through questionnaires which included questions on the general characteristics of the teachers, their nutritional education status, and the source of nutrition information. In addition, the portion sizes of items on the menu currently provided to children were measured and the data were analyzed. To assess the effectiveness of education in determining serving size, the subjects were randomly equally divided into two groups. In the first group (n = 60) theoretical education on nutrition and serving sizes was given, whereas in the second (n = 60), practical education on these topics was provided. Results: The difference between the actual portion size of rice and the serving size announced on the menu was observed to decrease along with the increase in the experience of the teacher, although the differences in the main dish and kimchi were higher. The gap between the serving size mentioned in the menu and the portion size distributed widened as the age of the teachers increased. Notably, the difference between the portion size and the serving size of food decreased after both practical and theoretical education. Furthermore, the effect of education on the serving size of the main dishes (p < 0.001), side dishes (p < 0.01), and kimchi (p < 0.01) was observed to be greater in the practical education group than in the theoretical education group. Conclusion: Regular education should be provided to teachers on the serving sizes mentioned in the menu, as the quantity of food served depends on the experience and age of teachers. In the case of rice, theoretical education alone sufficed to ensure a proper serving size. However, hands-on training on the main and side dishes, and kimchi would be much more helpful.

• Journal of Microbiology and Biotechnology
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• 제26권1호
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• pp.72-79
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• 2016

The fungal morphologies and pellet sizes were controlled in acetophenone reduction by Rhizopus oryzae. The acetophenone conversion and (S)-phenylethanol enantiomeric excesses (e.e.) reached the peak after 72 h of incubation when using pellets with 0.54 mm diameter, which showed an excellent performance compared with suspended mycelia, clumps, and pellets with 0.65 or 0.75 mm diameter. Furthermore, nano-sized acetophenone was used as a substrate to improve the performances of biotransformation work. The results showed that the conversion of nanometric acetophenone and (S)-phenylethanol e.e. reached the maximum (both >99%) after 32 h of incubation when using 0.54 mm diameter pellets, at least 24 h in advance of the control group. On the other hand, Tween 80 and 1, 2-propylene glycol showed low or no toxicity to cells. In conclusion, pellets and acetophenone nanoemulsions synergistically result in superior performances of acetophenone reduction.

• 대한수의학회지
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• 제56권3호
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• pp.177-181
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• 2016

Mini-pigs have been widely employed in preclinical studies to explore new therapeutic strategies for diseases of the human urinary system; however, the normal reference of the renal artery has not been clearly investigated in the mini-pig model. Therefore, we aimed to establish a normal reference of the radiological morphology of the renal artery in mini-pigs by renal angiography via catheterization of the carotid artery. The renal angiographies obtained from 15 mini-pigs were evaluated to determine the orifice from the aorta, facing direction, size and the number of branches of renal arteries. Cranio-laterally facing renal arteries with 2 distal branches were mainly observed in the renal artery of mini-pigs. Both sides of the renal artery presented symmetrical sizes; however, the right renal artery orifice from the aorta was located more cranially than the left counterpart. The results of this study will contribute to radiological diagnosis of the renal artery as well as preclinical studies of mini-pigs.

• 대한물리의학회지
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• 제17권1호
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• pp.1-9
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• 2022

PURPOSE: This study examined the effects of ankle kinesio taping on the balanced control capabilities of normal adults, stroke patients, and musculoskeletal patients. METHODS: One thousand articles were searched, and 100 of them were selected as taping papers. Subsequently, 33 papers classified according to balance, muscle strength and pain were analyzed according to the effect size and age group. RESULTS: The effect of ankle kinesio taping on balance control was examined by dividing the effect size into three groups according to the type of disease. Studies with normal adults had a large effect size of 1.213, whereas the effect size of stroke studies was .377, which was small. Studies on musculoskeletal disorders had a large effect size of 1.429. All three groups did not include 0 in the 95% confidence interval, indicating a significant effect. CONCLUSION: The effect of kinesio taping on balance control was positive in all subjects, including normal adults, stroke patients, and musculoskeletal patients. On the other hand, in terms of the effect size of kinesio taping on balance control, musculoskeletal patients and normal adults had larger effect sizes than stroke patients.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2022년도 추계학술대회
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• pp.19-21
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• 2022

자기 지도 학습을 이용한 이상 탐지는 일반적으로 합성 데이터를 생성해 정상과 이상을 학습하고, 실제 이상 데이터를 테스트 데이터로 사용하여 이상 탐지 성능을 측정한다. 정상 데이터와 유사한 합성 데이터를 생성하기 위해 기존 연구에서는 원본 이미지에서 특정 패치를 자르고 붙이는 식으로 합성 데이터를 생성한다. 이런 방식에서 정상 데이터와 유사한 정도는 패치 개수와 크기에 따라 달라지므로 이상 탐지 성능에 영향을 미칠 수 있다. 본 연구에서는 패치 크기 및 개수를 다르게 하여 합성 데이터를 생성한 뒤 사전 학습된 모델을 사용하여 정상 데이터와의 유사성 측정 및 분석을 진행하였고 모델을 학습시켜 이상 탐지 성능을 측정하여 보았다.

• Geomechanics and Engineering
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• 제35권5호
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• pp.475-486
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• 2023

Ballast particles have an irregular shape and are discrete in nature. Due to the discrete nature of ballast, it exhibits complex mechanical behaviour under loading conditions. The discrete element method (DEM) can model the behaviour of discrete particles under a multitude of loading conditions. DEM is used in this paper to simulate a series of three-dimensional direct shear tests in order to investigate the shear behaviour of railway ballast and its interaction at the microscopic level. Particle flow code in three dimension (PFC3D) models the irregular shape of ballast particles as clump particles. To investigate the influence of particle size distribution (PSD), real PSD of Indian railway ballast specification IRS:GE:1:2004, China high-speed rail (HSR) and French rail specifications are generated. PFC3D built-in linear contact model is used to simulate the interaction of ballast particles under various normal stresses, shearing rate and shear box sizes. The results indicate how shear resistance and volumetric changes in ballast assembly are affected by normal stress, shearing rate, PSD and shear box size. In addition to macroscopic behaviour, DEM represents the microscopic behaviour of ballast particles in the form of particle displacement at different stages of the shearing process.

• Communications for Statistical Applications and Methods
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• 제15권5호
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• pp.643-653
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• 2008

Application of the bootstrap to problems in multistage inference procedures are discussed in normal and other related models. After a general introduction to these procedures, here we explore in multistage fixed precision inference in models. We present numerical comparisons of these procedures based on bootstrap critical points for small and moderate sample sizes obtained via extensive sets of simulated experiments. It is expected that the procedure based on bootstrap leads to better results.