• Title/Summary/Keyword: correlation coefficients

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Study of Ocular Components in Determining the Refractive State of the Eye (굴절이상을 결정하는 안광학 요소에 관한 연구)

  • Seo, Y.W.;Choe, Y.J.
    • Journal of Korean Ophthalmic Optics Society
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    • v.4 no.1
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    • pp.7-14
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    • 1999
  • The purpose of this study is to evaluate the relationship between ocular components and refractive error for human eye. Ocular components were measured by keratometry, phakometry, and ultrasonography. Refractive error was measured by subjective refraction on 38 subjects aged from 17 to 30. The results were as follows; 1) Refractive error and axial length, vitreous chamber depth, axial length/corneal radius were highly correlated that the correlation coefficients were 0.95, 0.96, 0.95, respectively. 2) Refractive error and corneal radius, corneal power, lens thickness were correlated with the correlation coefficients for 0.60, 0.66, 0.67 respectively. 3) There were no significant correlation between refractive error and corneal thickness.

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Variation of Quantitative Charactes and Chemical Components on Local Collections of Perilla frutescens (수집종 자소의 주요 양적형질의 변이와 화학성분 함량)

  • 박희진
    • Korean Journal of Plant Resources
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    • v.7 no.2
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    • pp.109-114
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    • 1994
  • Followings are resulted through the analysis of the maln characters and the leaf ingredients, which is on the purpose of getting the basic materials to improve jaso and increase its production.Of the introduced varieties, Jukyeubjaso-stem length is 180cm, ear length is 37cm, No. of branches ofstem is 27, leaf length Is 16cm, leaf width Is 15cm-has better character than any other. Gurye local-stem length is 179cm, ear length is 38cm-is taken to be the best in the Geo-ecotypic.In the yield of leaf and seed, JukyeubJaso Is 727kg/10a, the greatest of all. In the leaf softness, allthe Inirorluced varieties are about 3.5 degrees, the Geo-ecotypic, about 2. The qualify of the introducedvat'ieties is better· than that of the Geo-ecotypic. Estimating on the chemical analysis of leaf,Jukyeubjaso has Protein 21.84%, Total carbohydrate 7.91%, Fe 126ppm, and Gurye lacal has Protein21.7 a, Total carbohydrate 8.4%, Fe 148ppm, expressing the highest. In correlation coefficients of leafchemical components, between protein and Total carbohydrate, Protein and Mn, protein and Fe, Pro-tein and Cu all the sorts show the positive correlation. Among them the Geo-ccoyplcs show the hlghestsignificance.

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Performance of Evaporation Heat Transfer Enhancement and Pressure Drop for Liquid Nitrogen (액체질소에 대한 증발 열전달 촉진 및 압력강하 성능)

  • Nam, Sang-Chul;Lee, Sang-Chun;Park, Byung-Duck
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.3
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    • pp.363-372
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    • 2000
  • An experiment was carried out to evaluate the heat transfer enhancement and the pressure drop characteristics for liquid nitrogen using wire-coil-insert technique under horizontal two-phase conditions. The tube inner diameters were 8 mm and 15 mm, respectively and the tube length was 4.7 m. The helix angle of the wire coil insert was $50^{\circ}$ and its length was 4.7 m. Heat transfer coefficients for both the plain and the enhanced test tubes were calculated from the measurements of temperatures, flow rates and pressure drops. A correlation in a power-law relationship of the Nusselt number, Reynolds number and Prandtl number for the heat transfer was proposed which can be available for design of cryogenic heat exchangers. The correlation showed that heat transfer coefficients for the wire-coil inserts were much higher than those for plain tubes, increased by more than $1.8{\sim}2.0$ times depending upon the range of the equivalent Reynolds number. The correlation was compared with other various correlations in the turbulent flow conditions.

A Biotechnological Study on the Sleeve Form Variation according to Arm Movements for Elementary Schoolgirls (학령기 어린이의 상지동작에 관한 인간공학적 연구)

  • Lee Sook Nyeu
    • Journal of the Korean Society of Clothing and Textiles
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    • v.10 no.3
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    • pp.17-25
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    • 1986
  • The objectives of this study are to investigate the variation of the sleeve form by changing arm movements and to study the relationship among the three aspects of sleeve (sleeve height, width and armhole girth) by changing arm movements. Plasrun gyps were used for this experimental research. The subjects of this study were elementary schoolgirls (9$\~$12 years old). Arm mevements were 4 types($0^{\circ},\;45^{\circ},\;90^{\circ},\;135^{\circ}$) to the vertical directions. The statistical methods used to analyze the data included mean, standard deviation, the Pearson's correlation coefficients and coefficients of determination. The results obtained from this study were as follows; 1. According to the arm movements, the sleeve form changed more in the front than in the back. 2. As the arm movements were increased vertically, the heights of sleeves and the girths of the armholes were decreased, and the widths of sleeves were increased. 3. Variation rates by changing arm movements were different according to the variation of arm movement, and were the highest in sleeve height. 4. There was a negative correlation between sleeve height and width, and a positive correlation between sleeve height and armhole girth.

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Real Effect of pH on CIE L*, a*, and b*, of Loins during 24 h Chilling of Beef Carcasses

  • Min, J.S.;Kim, I.S.;Yoon, Y.T.;Lee, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.2
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    • pp.279-282
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    • 2002
  • Twenty six male Hanwoo (Korean cattle) carcasses were measured for pH, temperature and instrumental color changes of loins during 24 h post-mortem carcass chilling at $4^{\circ}C$ in the cooler. The average internal temperature of loins was about $5^{\circ}C$ after 24 h of chilling, and with the exclusion of those with an ultimate pH>6.0 (dark-cutters), the average pH value was 5.5. When all carcasses were considered for the partial correlation coefficient between color and pH, with the temperature effect excluded, CIE $L^*$, $a^*$ and $b^*$ seemed to be affected significantly by pH during chilling process (p<0.001). However, when carcasses with dark-cutting condition were excluded, the correlation coefficients were much lower. In contrast, when the partial correlation coefficients between color and temperature, excluding the effect of pH on them, were analyzed, the relationship between color and temperature did not change much after values of DFD (dark, firm, dry) beef were excluded. The results suggested that the known interrelationship of color and pH in chilled beef loins be mainly due to the influence of temperature on pH and color.

The Correlation of Electronegativity with Ionization Potential and Atomic Polarizability (원자의 이온화에너지 및 전기음성도와 편극성과의 상관관계)

  • Hae Soo Lee;Chang Hwan Rhee
    • Journal of the Korean Chemical Society
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    • v.35 no.5
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    • pp.469-479
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    • 1991
  • According to the recent paper by B. Fricke (J. Chem. Phys. 84, 862 (1986)), it is reported that the atomic polarizability (${\alpha}$) correlates very strongly with the first ionization potential (IP) within the groups of elements. In our study, we obtained very significant correlations between $ln\alpha$ and IP as well as lnIP by employing the least squares method. In examining the correlations of various atomic electronegativities with their first ionization potentials and the atomic polarizability within the groups of elements, good correlation coefficients are obtained except for groups 3a and 4a. Within the periods of elements, good correlation coefficients are obtained with no exception. This allows a very good prediction of various atomic polarizabilities undetermined.

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Monitoring of Non-point Source Pollutants Generated by a Flower Farm

  • Choi, Byoungwoo;Kang, Meea
    • The Journal of Engineering Geology
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    • v.24 no.4
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    • pp.463-471
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    • 2014
  • This paper considers the effect of rainfall on non-point source (NPS) pollutant loads. The impact of runoff on the occurrence of NPS pollutants was found to be influenced by rainfall amount, rainfall intensity, and the number of antecedent dry days (ADD), both independently and in combination. The close correlation ($R^2$ = 0.9920) between rainfall and runoff amounts was demonstrated at the study site (a flower farm) over the period between January 2011 and December 2013. The relationships among pollutant levels, runoff, and rainfall was not satisfactory results except for the Biochemical Oxygen Demand ($BOD_5$). The correlation coefficients between $BOD_5$, and both runoff and rainfall, were greater than 0.92. However, the relationships of other pollutants, such as Suspended Solid (SS), Chemical Oxygen Demand ($COD_{Mn}$), Total Nitrogen (TN), and Total Phosphorus (TP), with runoff and rainfall had correlation coefficients of less than 0.70. The roles of rainfall was different from rainfall categories on the occurrence of runoff. Instantaneous rainfall intensity was a principle factor on the occurrence of runoff following light rainfall events (total ${\leq}30mm$). For rainfall of intermediate intensity (total precipitation 31-50 mm), the combined effect of both average rainfall intensity and ADD was found to influence runoff generation. We conclude that the control of NPS pollutants with the reflection of the climate change that makes the remarkable effect of amounts and forms on the rainfall and runoff.

A study on the Drapability of woven fabrics - With the Drape Coefficient - (직물의 Drape성에 관한 연구 -Drap 계수를 중심으로 -)

  • 안필자
    • Journal of the Korean Home Economics Association
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    • v.23 no.3
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    • pp.9-16
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    • 1985
  • There are two standards for evaluation of fabric aesthetics, the feeling of fabric and the fabric sense of sight. Its drapalility with lustre is one of factors to decide the fabric sense of sight. This study was carried out to investigate the drape property property of fabrics. The fabric characteristics and the physisical properties of fabrics were tested. And the effect of the laundering on the drape properties was examined. RESULTS : 1. The drape coefficients of sampled fabrics were increasd as the thickness of fabrics were increased, excluding the fabric consisting of 60% polyester$\times$40% wool. 2. The drape coefficient of sampled fabrics were decreased as the cover faders of fabrics were increased, excluding the summer clothes and the fabrics of 100% wool. 3. The drape coefficients of fabrics other than sumer clothes were increased as the weight of fabrics were in creased. 4. Positive correlation was observed between the stiffness and the drape coefficient. 5. Negative correlation was observed between the fabric shrinkage and the drape coefficient. 6. The drape coefficient was decreased to a certain limit by laundering.But as the laundering was repeated up to certain number, the drape coefficient and the node number, a significant correlation was observed between the drape coefficient and the node shape.

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Pool Boiling Heat Transfer Correlation for Pure Refrigerants (순수냉매의 풀비등 열전달 상관식)

  • 고영환;김종곤;송길홍;정동수;김영일
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.10
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    • pp.941-949
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    • 2000
  • Pool boiling heat transfer coefficients (HTCs) of HCFC123, CFC11, HCFC142b, HFC134a, CFC12, HFC22, HFC125 and HFC32 on a horizontal smooth tube have been measured. The experimental apparatus is specially designed to simulate the real heat transfer tube with the use of the secondary fluid of water as a heat source rather than a conventional electric heat source. Data were taken in the order of decreasing heat flux starting at $80 ㎾/m^2\; and \;ending\; at\; 5㎾/m^2\;in\; the\; poo\;l temperature\; at\; 7^{\circ}C$, Test results showed that HTCs of HFC125, and HFC32 are 50~67% higher than those of HCFC22. It is also found that some of the popular pool boiling heat transfer correlations in the literature are not good to predict the HTCs of newly developed alternative refrigerants. A new correlation was developed by a regression analysis which is based upon the consistent data obtained in this study and it showed an excellent agreement with all experimental data having an absolute mean deviation of less than 10%.

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Multimedia Watermark Detection Algorithm Based on Bayes Decision Theory (Bayes 판단 이론 기반 멀티미디어 워터마크 검출 알고리즘)

  • 권성근;이석환;김병주;권기구;하인성;권기룡;이건일
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.7A
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    • pp.695-704
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    • 2002
  • Watermark detection plays a crucial role in multimedia copyright protection and has traditionally been tackled using correlation-based algorithms. However, correlation-based detection is not actually the best choice, as it does not utilize the distributional characteristics of the image being marked. Accordingly, an efficient watermark detection scheme for DWT coefficients is proposed as optimal for non-additive schemes. Based on the statistical decision theory, the proposed method is derived according to Bayes decision theory, the Neyman-Pearson criterion, and the distribution of the DWT coefficients, thereby minimizing the missed detection probability subject to a given false alarm probability. The proposed method was tested in the context of robustness, and the results confirmed the superiority of the proposed technique over conventional correlation-based detection method.