• Title/Summary/Keyword: 2-D correlation

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The Correlation between Holmberg's diameter and de Vaucouleurs' diameter of External Galaxies (Holmberg 은하 직경과 de Vaucoluleurs 은하 직경의 상관 관계)

  • 홍정호;천문석
    • Journal of Astronomy and Space Sciences
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    • v.2 no.2
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    • pp.117-129
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    • 1985
  • Holmberg's diameters of galaxies $D_{h}$ were obtained from Holmberg catalogue. The difference between Holmberg's diameter and de Vaucouleurs' face-on diameter is campared with the results of Heidmann et al. The difference obtained in this paper is smaller than that of Heidmann at al. Also, the correlation between $D_{h}$ and $D_{v}$ was obtained for each type in de Vaucouleurs' classification of galaxies. It shows that $D_{h}$ is overestimated that $D_{v}$.

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Neighbor Discovery Scheme based on Spatial Correlation of Wireless Channel (무선채널의 공간적 연관성을 이용한 주변단말 탐색방안)

  • Lee, Woongsup
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.10
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    • pp.2256-2262
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    • 2015
  • Recently, device-to-device (D2D) communication has been considered as key technology for future cellular system, because it can solve the problem of excessive data traffic increment and can also provide new communication services. Herein, we propose new neighbor discovery for D2D communication and examine its performance. Our proposed scheme is proximity beacon based discovery in which wireless resource for pilot transmission is assigned based on the spatial correlation of wireless channel and sensing period is adjusted according to target accuracy such that power consumption can be reduced. The performance of our propose scheme is analyzed mathematically and verified through computer simulations.

Cross-Correlation Distribution of a p-ary m-Sequence Family Constructed by Decimation (Decimation에 의해 생성된 p-진 m-시퀀스 군의 상호 상관 값의 분포)

  • Seo, Eun-Young;Kim, Young-Sik;No, Jong-Seon;Shin, Dong-Joon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.9C
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    • pp.669-675
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    • 2008
  • For an odd prime p, n=4k and $d=((p^2k+1)/2)^2$, there are $(p^{2k}+1)/2$ distinct decimated sequences, s(dt+1), $0{\leq}l<(p^{2k}+1)/2$, of a p-ary m-sequence, s(t) of period $p^n-1$. In this paper, it is shown that the cross-correlation function between s(t) and s(dt+l) takes the values in $\{-1,-1{\pm}\sqrt{p^n},-1+2\sqrt{p^n}\}$ and their, cross-correlation distribution is also derived.

A study on the correlation between the result of electrical resistivity survey and the rock mass classification values determined by the tunnel face mapping (전기비저항탐사결과와 터널막장 암반분류의 상관성 검토)

  • 최재화;조철현;류동우;김학규;서백수
    • Proceedings of the Korean Geotechical Society Conference
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    • 2003.03a
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    • pp.265-272
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    • 2003
  • In this study, the rock mass classification results from the face mapping and the resistivity inversion data are compared and analyzed for the reliability investigation of the determination of the rock support type based on the surface electrical survey. To get the quantitative correlation, rock engineering indices such as RCR(rock condition rating), N(Rock mass number), Q-system based on RMR(rock mass rating) are calculated. Kriging method as a post processing technique for global optimization is used to improve its resolution. The result of correlation analysis shows that the geological condition estimated from 2D electrical resistivity survey is coincident globally with the trend of rock type except for a few local areas. The correlation between the results of 3D electrical resistivity survey and the rock mass classification turns out to be very high. It can be concluded that 3D electrical resistivity survey is powerful to set up the reliable rock support type.

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Characteristics of 2nd to 4th Digit Ratio according to Type of Handedness in University Students (대학생의 손잡이 유형에 따른 손가락 길이비(2D:4D)의 특성)

  • Kim, Sooil;Cho, Keun-Ja
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.3
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    • pp.1245-1251
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    • 2013
  • The aim of this study is to identify characteristics of 2D:4D according to type of handedness. Data was collected from October, 4th, 2010 to April, 30th, 2012. After handedness assessment, 2nd and 4th finger length were measured by vernier calipers. This study showed remarkable gender difference of 2D:4D in left hand for left handers and right hand for right handers, However, there was no significant difference according to type of handedness in each gender. The correlation between left and right 2D:4D in males right handedness was higher than that of male left handedness, otherwise, in case of female, that of left handedness was higher than that of right handedness. The results of this study suggest that the 2D:4D of left handedness does not differ from that of right handedness, however, gender difference and correlation between left and right 2D:4D show different characteristics according to handedness.

CORRELATION BETWEEN CARIES EXPERIENCE AND ANXIETY TO DENTIST IN PRESCHOOL CHILDREN (유치원 아동의 우식경험도와 치과의사에 대한 불안의 상관성)

  • Lee, Kwang-Hee;Kim, Dae-Eop
    • Journal of the korean academy of Pediatric Dentistry
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    • v.21 no.2
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    • pp.456-462
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    • 1994
  • The purpose of this study was to investigate the relationship between the caries experience and anxiety level to the dentist in the preschool children. 511 preschool children were brought to the dental hospital and examined for caries experience. Caries experience was measured as dDT index, fFT index, dDfFT index, dDT rate, and fFT rate. Children were requested to draw a dentist. Drawings were analyzed by the method of Human Figure Drawing Anxiety Score. Pearson correlation coefficents and their significance were calculated between caries experience and anxiety scores. There were significant negative correlation between fFT index and anxiety scores, between dDfFT index and anxiety scores, and between fFT rate and anxiety scores. There was significant positive correlation between dDT rate and anxiety scores. The results seemed to suggest that dental treatment experience reduced children's anxiety toward dentists. But, because there was obvious negative correlation between age and anxiety scores, age factor should be considered in the interpretation of the results.

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Clinical Study on the Correlation between Retention of Fluid, namely Damum(痰飮) and Dark Circles under Eyes (다크 서클(Dark Circles under Eyes)과 담음(痰飮)의 연관성에 관한 연구)

  • Cho, Ga-Young;Roh, Ho-Sik;Kim, Su-Jong;Kim, Eun-Joo;Park, Hye-Yoon;Kim, Duck-Hee;Kim, Han-Gon
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.12 no.2
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    • pp.49-60
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    • 2008
  • Objectives: The aim of this study was to investigate correlation of the phlegm-retained fluid, namely Damum(痰飮) and dark circles under eyes. Methods: 2 males and 11 females aged 26-60 years were participated in this study. They were asked the intensity of 29 symptoms related with Damum(痰飮) including dark circle with the questionnaire published by the Journal of the Korea Institute of Oriental Medical Diagnostics. Three skin researchers including OMD graded the dark circles by inspection. We took the pictures around eyes by Facial Stage (Moritex, Japan) and analyzed the skin color by Image-Pro Plus (Media Cybernetics, USA). Results: There was statistically significant correlation between Damum(痰飮) and dark circles measured by self, inspectors and image analysis. Conclusions: In the Oriental Medicine, It is reported that the shadows under eyes are the sign of the retention of fluid, Damum(痰飮). In our study, that shadows, namely dark circles, has correlation with the symptoms of Damum(痰飮). Especially, the correlation between inspected grade and image analysis was very high. According to the above results, it is proved that dark circles under eyes are important diagnostic sign of Damum(痰飮).

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A Study on the 2D:4D Ratio and Its Correlation with the Sasang Constitution and the MBTI Preference Types (2D:4D 비율과 사상체질 및 MBTI 선호유형간의 상관성 연구)

  • Kwon, Oh-Hyeon;Go, Ho-Yeon;Lee, Jae-Hyok
    • Journal of Oriental Neuropsychiatry
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    • v.28 no.3
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    • pp.157-164
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    • 2017
  • Objectives: The purpose of this study is the research of the 2D:4D ratio and its correlation with the Sasang constitution and the MBTI preference types. Methods: A measurement of the 2D:4D ratios of 101 South Korean medical students was performed, the QSCC-II and PSSC-2004 were used to diagnose the Sasang constitution, and MBTI testing was performed to classify the preference types. Results: In the relationship between the Sasang constitution and the 2D:4D ratios, a statistically significant difference is absent in the 2D:4D ratios of the group comprising both sexes in the order of Taeumin, Soyangin, and Soeumin. A statistically significant difference is also lacking in the 2D:4D ratios of the male-only group in the order of Taeumin, Soyangin, and Soeumin. The 2D:4D ratios are higher in the female group only, but again a statistically significant difference is absent. In the 2D:4D ratios according to the MBTI preference type, the 2D:4D ratios of the I, S, F, and P types are higher in the unisex group, but a significant difference is not evident. The 2D:4D ratios of the E, N, F, and P types are higher in the male-only group, but again a significant difference is not evident. In the female-only group, the mean of the 2D:4D ratios of the I, S, F, and P types is higher, but a significant difference is not identifiable. Conclusions: The Sasang constitution and the MBTI preference types did not show statistically significant differences regarding the 2D:4D ratios of the male, female, and unisex groups.

X Control Charts under the Second Order Autoregressive Process

  • Baik, Jai-Wook
    • Journal of Korean Society for Quality Management
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    • v.22 no.1
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    • pp.82-95
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    • 1994
  • When independent individual measurements are taken both $S/c_4$ and $\bar{R}/d_2$ are unbiased estimators of the process standard deviation. However, with dependent data $\bar{R}/d_2$ is not an unbiased estimator of the process standard deviation. On the other hand $S/c_4$ is an asymptotic unbiased estimator. If there exists correlation in the data, positive(negative) correlation tends to increase(decrease) the ARL. The effect of using $\bar{R}/d_2$ is greater than $S/c_4$ if the assumption of independence is invalid. Supplementary runs rule shortens the ARL of X control charts dramatically in the presence of correlation in the data.

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Predicting of Uncorrected Astigmatism from Decimal Visual Acuity in Spherical Equivalent

  • Moon, Byeong-Yeon;Kim, Sang-Yoeb;Cho, Hyun Gug
    • Journal of the Optical Society of Korea
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    • v.17 no.2
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    • pp.219-223
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    • 2013
  • The purpose of this study was to determine the relationship between the spherical equivalent visual acuity (VA) and uncorrected astigmatism. On 108 emmetropic eyes, the spherical equivalent VA was measured for cross cylindrical lens (CC lens)-induced astigmatic eyes and the VA-astigmatism relation determined. On 158 astigmatic eyes, the spherical equivalent VA and corrected astigmatism were measured and the measured values were compared with the calculated values from the VA-astigmatism relation by correlation coefficient analysis. Subsequent to that, the relationship between spherical equivalent VA and uncorrected astigmatism was made. The relationship was fitted for an exponential equation. Correlation coefficient between calculated values by equation and measured values for astigmatic eyes was 0.991 (p<0.01). The relationship between the spherical equivalent VA and the uncorrected astigmatism was decided as follows (spherical equivalent VA / uncorrected astigmatism): 1.0 / 0.25 D, 0.9 / 0.50 D, 0.8 / 0.75 D, 0.7 / 1.00 D, 0.6 / 1.25 D, 0.5 / 1.50 D, 0.4 / 2.00 D, 0.3 / 2.50 D, 0.2 / 3.00 D, 0.1 / 4.00 D, and 0.05 / 4.75 D. In conclusion, the relationship table devised from this study is a useful reference for predicting uncorrected astigmatism by measurement of decimal VA in spherical equivalent.