• 한국농공학회지
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• 제26권2호
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• pp.59-68
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• 1984

The Purpose of this study was to investigate the effect of the change in misture content on some physical properties of grains, and some relations amont the properties. Materials included ere rough rice, brown rice, barley and wheat with the range of moisture content of 6~26 percent, 7~25 percent, 10~24 percent and 6~22 percent, respectively. Kernel dimension, sphericity, kernel weight, and volume were included as the physical properties of the grains. The results obtained are summarized as follows; 1. The ratio of grain length to the thickness was in the range of 3.59~4.16 for rough rice(Indica type), 2.98~3.27 for rough rice(Japonica type), 3.25 for brown rice (I.T.), 2.14~2.38 for brown rice(J.T.), 2.92~3.13 for barley and 2.10~2.21 for wheat, respectively. 2. The sphericity was found to be 42 percent for rough rice(I.T.), 48 percent for rough rice(J.T.), 52 percent for brown rice(I.T.), 62 percent for brown rice(J.T.), 45 percent for barley and 61 percent for wheat, respectively. 3. The kernel weight of grains was linealy increased with the increase of moisture content. At a specified moisture centent of 14 percent, the kernel weight was shown to be in the range of 4.72${\times}10^{-5}$~3.58${\times}10^{-5}$kg for wheat, 3.60${\times}10^{-5}$~3.12${\times}10^{-5}$kg for barley, 2.80${\times}10^{-5}$~2.35${\times}10^{-5}$kg for rough rice, and 2.24${\times}10^{-5}$~1.82${\times}10^{-5}$kg for brown rice, respectively. 4. The kernel volume was linearly increased with increase of moisture content. The rate of increase was significantly low for rough rice in comparison with the remaining grains. The kernel volume, at a specified moisture content of 14 percent, was in the range of 3.51${\times}10^{-8}$~2.76${\times}10^{-8}m^3$ for wheat, 2.84${\times}10^{-8}$~2.43${\times}10^{-8}m^3$ for barley, 2.93${\times}10^{-8}$~1.97${\times}10^{-8}m^3$ for rough rice, and 1.61${\times}10^{-8}$~1.29${\times}10^{-8}m^3$ for brown rice, respectively. 5. The kernel volume of grains was found to be related to the length, width, thickness and kernel weight as a exponential function. The kernel volume was shown to have correlation coefficient to the length factor rough rice and barley which were of low sphericity, while the width factor was predominant for brown rice and wheat which was of high sphericity.

• Journal of Biosystems Engineering
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• 제33권2호
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• pp.101-105
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• 2008

Some physical properties of rapeseed such as geometric properties (linear dimensions, sphericity, seed volume, surface area) and gravimetric properties (the mass of one thousand seeds, bulk density) were analyzed at five levels of moisture content of 10.03, 14.91, 20.07, 25.06 and 30.12% (w.b.). The physical properties of rapeseed were evaluated as a function of seed moisture content. In the moisture range, when the moisture content increase, sphericity decreased from 0.946 to 0.927, and geometric mean diameter, seed volume and surface area increased from 2.17 to 2.31 mm, 5.58 to $6.88 \;mm^3$ and 14.76 to $16.77\;mm^2$ respectively. Mass of one thousand seeds increased from 5.04 to 6.46 g. Bulk density decreased from 579.3 to $549.2\;kg/m^3$ due to swelling of the seed.

• The Korean Journal of Pain
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• 제30권4호
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• pp.243-249
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• 2017

Pain is subjective, while statistics related to pain research are objective. This review was written to help researchers involved in pain research make statistical decisions. The main issues are related with the level of scales that are often used in pain research, the choice of statistical methods between parametric or nonparametric statistics, and problems which arise from repeated measurements. In the field of pain research, parametric statistics used to be applied in an erroneous way. This is closely related with the scales of data and repeated measurements. The level of scales includes nominal, ordinal, interval, and ratio scales. The level of scales affects the choice of statistics between parametric or non-parametric methods. In the field of pain research, the most frequently used pain assessment scale is the ordinal scale, which would include the visual analogue scale (VAS). There used to be another view, however, which considered the VAS to be an interval or ratio scale, so that the usage of parametric statistics would be accepted practically in some cases. Repeated measurements of the same subjects always complicates statistics. It means that measurements inevitably have correlations between each other, and would preclude the application of one-way ANOVA in which independence between the measurements is necessary. Repeated measures of ANOVA (RMANOVA), however, would permit the comparison between the correlated measurements as long as the condition of sphericity assumption is satisfied. Conclusively, parametric statistical methods should be used only when the assumptions of parametric statistics, such as normality and sphericity, are established.

• Fisheries and Aquatic Sciences
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• 제19권7호
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• pp.30.1-30.7
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• 2016

Due to decreased supplies of marine resources and byproducts, new processing technologies for the development of analogs for natural fishery products are becoming increasingly important in the fishing industry. In the present study, we investigated the optimal processing conditions for flying fish roe analogs based on alginate hydrogels. Optimized processing of these analogs was performed by response surface methodology. The optimal processing conditions for the flying fish roe analogs (based on sphericity) were at a sodium alginate concentration of 2.41 %, calcium chloride solution curing time of 40.65 min, calcium chloride concentration of 1.51 %, and a reactor stir speed of $254{\times}g$. When the experiment was performed under these optimized conditions, the size (mm), sphericity (%), and rupture strength (kPa) of the analogs were $2.2{\pm}0.12$, $98.2{\pm}0.2$, and $762{\pm}24.68$, respectively, indicating physical properties similar to their natural counterparts.

• Journal of Astronomy and Space Sciences
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• 제32권3호
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• pp.247-256
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• 2015

In this work, an efficient method with which to evaluate the high-degree-and-order gravitational harmonics of the non-sphericity of a central body is described and applied to state predictions of a lunar orbiter. Unlike the work of Song et al. (2010), which used a conventional computation method to process gravitational harmonic coefficients, the current work adapted a well-known recursion formula that directly uses fully normalized associated Legendre functions to compute the acceleration due to the non-sphericity of the moon. With the formulated algorithms, the states of a lunar orbiting satellite are predicted and its performance is validated in comparisons with solutions obtained from STK/Astrogator. The predicted differences in the orbital states between STK/Astrogator and the current work all remain at a position of less than 1 m with velocity accuracy levels of less than 1 mm/s, even with different orbital inclinations. The effectiveness of the current algorithm, in terms of both the computation time and the degree of accuracy degradation, is also shown in comparisons with results obtained from earlier work. It is expected that the proposed algorithm can be used as a foundation for the development of an operational flight dynamics subsystem for future lunar exploration missions by Korea. It can also be used to analyze missions which require very close operations to the moon.

• 한국주조공학회지
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• 제26권1호
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• pp.40-45
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• 2006

Most of the work reported concerned the semi-solid processing of low melting point alloys, and in particular light alloys of aluminum and magnesium. The purpose of this paper is to develop a semi-solid microstructure of Cu alloys using electromagnetic stirring applicable for squirrel cage rotor of induction motor. The size of primary solid particle and the degree of sphericity as a function of the variation in cooling rate, stirring speed, and holding time were observed. By applying electromagnetic stirring, primary solid particles became finer and rounder relative to as-cast sample. As the input frequency increased from 30 to 40 Hz, particle size decreased. The size of primary solid particle was found to be decreased with increasing cooling rate. Also, it decreased with stirring up to 3 minutes but increased above that point. The degree of sphericity became closer to be 1 with hold time. Semi-solid microstructure of Cu alloys, one of the high melting point alloys, could be controlled by electromagnetic stirring.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.566-569
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• 1999

The blue emitting BAM Phosphor Particles with various compositions were Prepared by the spray Pyrolysis. The effect of composition on the morphology of BAM particles was Investigated. In the case of BaMgAl$_{10}$ /O$_{22}$ : Eu$^{2+}$, the morphology of particles with sphericity and non-aggregation characteristics disappeared after post-treatment at 1400 $^{\circ}C$ for 3 hrs. On the other hand, the ocher composition particles except BaMgAl$_{10}$ /O$_{22}$ : Eu$^{2+}$ maintained their original morphology after post-treatment, even if the particles were prepared at low temperatures in the spray pryrolysis. The BAM particles with MgAl$_{2}$/O$_4$as intermediate material at low post-treatment temperature had high thermal stability and maintained sphericity of particles after post-treatment. All the samples had main omission peak at 450 nm, which corresponds to blue emission. The optimum post-treatment temperature of BAM:Eu$^{2+}$ particles for the maximum PL(photoluminescence) intensity in the spray pylolysis was 1200 $^{\circ}C$ because of high crystallinity, Phase-Purity, and good morphology.ology.

• Investigative Magnetic Resonance Imaging
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• 제12권1호
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• pp.40-48
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• 2008

목적: 개정 도씨 술식과 승모판 고리성형을 동시에 시행한 후 심실의 형태와 기능의 초기 변화를 자기공명영상을 이용하여 평가하고자 하였다. 대상 및 방법: 총 21명의 확장성 심부전 환자를 대상으로 하여 8명에서 개정 도씨 술식을, 6명에서 승모판 고리성형을, 7명에서 두 수술을 동시에 시행하였다. 영화 자기공명영상을 이용하여 수술 전과 후에 좌심실의 형태와 기능을 평가하였다. 좌심실의 이완기말 용적과 수축기말 용적, 장축과 단축의 길이를 측정하고 이로부터 좌심실의 일회박출량, 박출률, 구형지수를 계산하여 구하였다. 이렇게 구해진 인자들을 분석하고 술식이 서로 다른 3군에서 어떻게 다른지 비교하고 두 수술을 동시에 시행할 때의 효과를 해석하였다. 결과: 자기공명영상은 수술 전 $12\;{\pm}\;15$ 일 (범위 1-58 일)과 수술 후 $38\;{\pm}\;50$ 일 (범위 7- 231 일)에 시행하였다. 두 수술을 동시에 시행한 군에서 다른 군에 비하여 수술 전 좌심실의 확장이 더 심하였고 수축력이 더 감소되어 있었다. 수술 후, 좌심실의 이완기말 용적과 수축기말 용적은 수술 형태와 관계없이 모든 환자에서 유의하게 감소하였다. 박출률은 개정 도씨 술식을 받은 환자 군에서만 유의하게 증가하였다 (25.4% to 40.7%). 구형지수는 개정 도씨 술식을 받은 환자에서는 증가하였고 승모판 고리성형을 받은 환자에서는 감소하였다 (0.65 to 0.78 vs. 0.75 to 0.65). 두 수술을 동시에 시행한 환자에서는 유의한 구형지수의 변화가 없었다. 결론: 개정 도씨 술식과 승모판 고리성형을 동시에 시행받은 확장성 심부전 환자에서 좌심실의 형태와 기능의 초기 변화는 좌심실 용적과 일회박출량의 현저한 저하이다. 승모판 고리성형에 의한 구형지수의 감소는 개정 도씨술식에 의한 구형지수의 증가에 의해 상쇄되어 좌심실의 형태는 변하지 않는다. 두 수술을 동시에 시행한 후 좌심실 박출률의 향상은 조기에 일어나지 않는다.

• Communications for Statistical Applications and Methods
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• 제4권2호
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• pp.581-588
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• 1997

Univariate F test is based on the multisample sphericity assumption. Robustness for tests of a main effect of the within-subjects factor was investigated when the assumptions of the onmibus F tests are violated in a split-plot design with one between-subjects factor using untrimmed data and trimmed data. The results indicate that when sample sizes are unbalanced and dispersion matrices are heterogeneous, the CIGA and the $CIGA_T$ tests better control Type I error rates than do the $F_T$test and the$\widetilde{\xi_T}$test.

• Communications for Statistical Applications and Methods
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• 제4권3호
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• pp.775-785
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• 1997

Robustness rates for repeated measures pairwise multiple comparison procedures were investigated in a split plot design with one between- and one within-subjects factor using untrimmed and trimmed data. Five factors were manipulated in the study: distribution, sphericity, variance-covariance heteroscedasticity, total sample size, and sample size ratio. The Welsch test (W) and the Welsch test on trimmed data $(W_{RT})$ performed better than the other procedures, but had a liberal tendency. The trimmed difference score Bonferroni Procedure $(B_{DT})$ was a good choice in some conditions.