• Title/Summary/Keyword: correlation length

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Quantitative Analysis of Factors Affecting Cobalt Alloy Clip Artifacts in Computed Tomography

  • Sim, Sook Young;Choi, Chi Hoon
    • Journal of Korean Neurosurgical Society
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    • v.56 no.5
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    • pp.400-404
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    • 2014
  • Objective : Clip artifacts limit the visualization of intracranial structures in CT scans from patients after aneurysmal clipping with cobalt alloy clips. This study is to analyze the parameters influencing the degree of clip artifacts. Methods : Postoperative CT scans of 60 patients with straight cobalt alloy-clipped aneurysms were analyzed for the maximal diameter of white artifacts and the angle and number of streak artifacts in axial images, and the maximal diameter of artifacts in three-dimensional (3-D) volume-rendered images. The correlation coefficient (CC) was determined between each clip artifact type and the clip blade length and clip orientation to the CT scan (angle a, lateral clip inclination in axial images; angle b, clip gradient to scan plane in lateral scout images). Results : Angle b correlated negatively with white artifacts (r=-0.589, p<0.001) and positively with the angle (r=0.636, p<0.001) and number (r=0.505, p<0.001) of streak artifacts. Artifacts in 3-D images correlated with clip blade length (r=0.454, p=0.004). Multiple linear regression analysis revealed that angle b was the major parameter influencing white artifacts and the angle and number of streak artifacts in axial images (p<0.001), whereas clip blade length was a major factor in 3-D images (p=0.034). Conclusion : Use of a clip orientation perpendicular to the scan gantry angle decreased the amount of white artifacts and allowed better visualization of the clip site.

A Study on the Roughness Length Spatial Distribution in Relation to the Seoul Building Morphology (서울시 건물형태에 따른 거칠기길이 분포특성 연구)

  • Yi, Chaeyeon;Kwon, Tae Heon;Park, Moon-Soo;Choi, Young Jean;An, Seung Man
    • Atmosphere
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    • v.25 no.2
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    • pp.339-351
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    • 2015
  • The purpose of this study is for the fundamental understandings about building morphological parameters and aerodynamic roughness parameters of Seoul, Korea using the detailed urban geographic information datasets. Applied roughness parameter calculations are based on a digital map of buildings with lot area polygons. The quality of the developed roughness length ($z_0$) of Seoul was evaluated with densely installed 107 automatic weather stations. The correlation coefficient results between averaged wind speeds of AWS data and averaged $z_0$ is -0.303 in night and -0.398 in day (200 m radii circles case). Further $z_0$ enhancement should follow by considering other surface features such as high tree and orography of Seoul. However, this study would meet the needs to for local- or meso-scale meteorological modeling applications of Seoul. However, further studies would require for enhancing the $z_0$ applications of Seoul.

Study of Real Somatotype and Perceived Body Classified by Body Index of College Women (여대생(女大生)들의 지수치(指數値)에 의한 체형(體型) 집단(集團)별 실제체형(實際體型)과 신체인식(身體認識)에 관한 연구(硏究))

  • Lee, Jung-Soon
    • Journal of Fashion Business
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    • v.11 no.5
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    • pp.100-109
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    • 2007
  • The purpose of this research is to study the recognition of real somatotype and body of college women. The study was carried out by classifying somatotypes into three categories based on the body index; slim, normal, and obese somatotype. The subject of this study was 106 college women, and real measurement and survey were used. Data was analyzed by SPSS 12.0 and cross tabulation analysis, t-test, Anova, and correlation analysis were operated. The result is as follows. 1. The height of the subjects was 163.5cm, weight was 53.3kg, Rohrer index was 1.2, BMI was 19.9, Vervaeck index was 84.4 and the classification based on the body index belonged to the normal group. 2. The characteristics of groups divided by the body index are that slimmer groups is longer in length factor and smaller in the factors related with volume than other groups. The characteristics of groups classified by self-consciousness shows significant difference in all girth factors, back intersyce breadth, front intersyce breadth, neck to nipple length, and nipple to nipple breadth. 3. Conscious about the somatotype with using body index generally shows similarity. In the length factor including height, slim somatotype group is perceived as longer than normal somatotype group, and in the girth factor including weight, normal somatotype group is recognized as bigger and thicker than others.

The Effect of Kindergarten's Factors on Athletic Movement Ability in $4{\sim}5$ Years Old Children (유치원 특성 변인이 $4{\sim}5$세 유아의 운동능력에 미치는 영향)

  • Oh, Yeon-Joo
    • Korean Journal of Human Ecology
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    • v.13 no.3
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    • pp.407-415
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    • 2004
  • The purpose of this study was to investigate the effect of kindergarten's factors on athletic movement ability in early childhood. The factors included teacher's perception of athletic movement, length of time for physical activity, and number of athletic facilities in the kindergarten. The subjects consisted of 551 children aged from four to five years in 8 private kindergartens. The instruments used for this study were the obstacle course of Project Spectrum for measuring athletic movement ability, and the questionnaire to investigate the teacher's perception, length of time for physical activity, and number of athletic facilities in the kindergarten. The data from all the tests were analyzed by correlation and regression analyses. The results of this study exhibited that the length of time for physical activity was the most important factor among three factors, and the teachers' perception of athletic movement and the number of athletic facilities in the kindergarten were also deciding factors for the children's athletic movement ability.

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Factors Affecting Mother's Adaptation to Breastfeeding (어머니의 모유수유 적응에 영향을 미치는 요인)

  • Kim, Sun-Hee
    • Journal of Korean Academy of Nursing
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    • v.40 no.2
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    • pp.225-235
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    • 2010
  • Purpose: The aim of this study was to identify factors which influence breastfeeding adaptation from among the following: parity and feeding behavior, social support, psychological, and demographic factors. Methods: The respondents were 179 breastfeeding mothers. Data were collected from June 2 to 19, 2009 at two community health centers and one pediatric outpatient department. Data were analyzed using the SPSS program and included descriptive statistics, t-test, ANOVA, correlation, and multiple regression. Results: The major findings of this study were: 1) Significant differences in the level of breastfeeding adaptation were related to number of children, current problems related to breastfeeding, and lay supporters. 2) Level of breastfeeding adaptation was significantly related to marriage satisfaction, proportion of breastfeeding, length of previous breastfeeding, planned length of breastfeeding, parenting stress, and encouragement to breastfeed given by medical personnel. 3) Regression analysis showed that parenting stress, marriage satisfaction, current problems related to breastfeeding, and proportion of breastfeeding explained 44.3% of variance for breastfeeding adaptation. Length of previous breastfeeding also explained 9.7% of breastfeeding adaptation among mothers who had breastfed an elder child. Conclusion: Mothers with lower marriage satisfaction, breastfeeding problems, and higher parenting stress require more help from their family and nurses for breastfeeding adaptation. Future research should include variables, such as mother's and baby's behavior related to breastfeeding, knowledge about breastfeeding, and attitude toward breastfeeding.

Genetic Analysis of Morphological Traits of Rice Grain and Their Inter-relationships

  • Chang, Jae-Ki;Yeo, Un-Sang;Oh, Byong-Geun;Lim, Sang-Jong;Yang, Sae-Jun;Kim, Soon-Chul;Moon, Huhn-Pal;Sohn, Jae-Keun
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.47 no.1
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    • pp.36-41
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    • 2002
  • Two rice varieties, 'Oochikara' with large grain and 'Hwayeongbyeo' and their progenies (F$_1$, F$_2$, B$_1$ and B$_2$) were tested to understand gene action of morphological traits of rice grain and their relationships. The evaluated traits were 1,000-grain weight, grain length, width, thickness, length-width ratio and chalkiness of brown rice. Correlation between grain weight and chalkiness was highly significant in the all progenies, and grain length were not associated with width and thickness in an F$_2$ population. Scaling test and jonit scaling test revealed that inheritance of grain traits were fitted to additive-dominance model without epistasis. Additive effects for the traits were much greater than the dominance effects.

A Radiographic Study on the Development of Roots of Mandibular Second Molars in Female (여성 하악 제2대구치 치근발육에 관한 방사선학적 연구)

  • Joong-Ho Choi;Myung-Yun Go
    • Journal of Oral Medicine and Pain
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    • v.17 no.2
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    • pp.119-128
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    • 1992
  • In order to evaluate the relationship of age with the developmental stage on mandibular second molars in female, the author examined the radiographs in standard films taken by intraoral paralleling technic and analysed the development of 620 roots of 310 females ranged from 10 to 18 years. The development was divided into 7 stages : Crown complete (Cr.C.), Root lengthed 1/4(R.1/4), Root length 1/2 (R.1/2), Rooth length 3/4 (R.3/4), Rooth length complete (R.C), Apex 1.2 closed (A. 1/2), Apical closure complete (A.C) The obtained results were as follows : 1. The formation of roots in fulllength of mandibular second molars was completed at 14.21-year-age in mesial root and at 14.96-year-age in distal root. 2. The formation of apical foramen of mandibular second molars was completed at 17.11-year-age in mesial root and at 17.53-year-age in distal root. 3. The mesial root of mandibular second molar was generally developed earlier than distal root (p<0.01) 4. Coefficients of correlation and regression equations between for age(Y) and the developmental stage of mandibular second molar(X) were "Y=1.53X+6.54, r=0.91 (p<0.01)" in mesial root and "Y=1.52X+7.11, r=0.92(p<0.01)" in distal root respectively.l root respectively.

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The Effect of Big Toe Flexors on Single Limb Balan (엄지발가락 굽힘근의 제한이 한발서기 균형에 미치는 영향)

  • Chung, Hyung-Kuk;Kim, Yong-Soo
    • Journal of Korean Physical Therapy Science
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    • v.17 no.3_4
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    • pp.51-58
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    • 2010
  • Purpose: The purpose of this study was to examine changes of postural sway between the normal group and treatment group of same people through COP movements. Methods: Fifty men with no history of sensory, neurological and orthopedic disorders were participated in this study. Participants were tested on single limb balance during 30 seconds on EMED system with bared foot. Each of them performed two methods and 5 trials totally each method: (1) non-treated group (2) treated group(with big toe flexion limitation). Data on the moving length, average velocity, instantaneous maximum velocity, mediolateral(x axis) maximum velocity, and anteroposterior(y axis) maximum velocity of COP were measured in single limb standing position. Results: The moving length and average velocity of COP were significant difference between normal and treatment group(p<0.05). On correlation of parameters, the faster average velocity of COP, the higher moving length, instantaneous maximum velocity, mediolateral maximum velocity, and anteroposterior maximum velocity of COP increase. The more Instantaneous maximum velocity of COP, the faster is anteroposterior maximum velocity of COP. Conclusions: Limitation of big toe flexors function affected single limb balance of the normal.

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Growth Characteristics of Early Peduncle Developing Plant in Korean Ginseng(Panax ginseng C.A. Meyer) (인삼에서 조기 화경출현개체의 생육특성)

  • 정찬문;남기열;김요태
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.1
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    • pp.92-97
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    • 1989
  • The study has carried out to investigate the possibility of application of the emerged-peduncle at the 2 year -old plant for ginseng breeding. In the 2 and 3 year-old plant, growth habits of aerial parts of plants that had the inflorescence showed higher vigor in leaf length, number of leaves, rate of fruitage and fertility, and roots yield than those of non-inflorescence. Generally, characteristics such as stem diameter, stem length, leaf length and number of leaves showed highly significant positive-correlation with root weight and fruitage. The trends of characteristics of plant that has inflorescence at the 2 year-old plant was shown one-year faster pattern than the plant that has non-inflorescence. As these results, selection of the plants which have inflorescence at the 2 year-old plant will provide valuable aid for ginseng breeding.

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DEVELOPMENT OF A TOY INTERFEROMETER FOR EDUCATION AND OBSERVATION OF SUN AT 21 cm

  • Park, Yong-Sun;Kim, Chang-Hee;Choi, Sang-In;Lee, Joo-Young;Jang, Woo-Min;Kim, Woo-Yeon;Jeong, Dae-Heon
    • Journal of The Korean Astronomical Society
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    • v.41 no.3
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    • pp.77-81
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    • 2008
  • As a continuation of a previous work by Park et al. (2006), we have developed a two-element radio interferometer that can measure both the phase and amplitude of a visibility function. Two small radio telescopes with diameters of 2.3 m are used as before, but this time an external reference oscillator is shared by the two telescopes so that the local oscillator frequencies are identical. We do not use a hardware correlator; instead we record signals from the two telescopes onto a PC and then perform software correlation. Complex visibilities are obtained toward the sun at ${\lambda}\;=\;21\;cm$, for 24 baselines with the use of the earth rotation and positional changes of one element, where the maximum baseline length projected onto UV plane is ${\sim}\;90{\lambda}$. As expected, the visibility amplitude decreases with the baseline length, while the phase is almost constant. The image obtained by the Fourier transformation of the visibility function nicely delineates the sun, which is barely resolved due to the limited baseline length. The experiment demonstrates that this system can be used as a "toy" interferometer at least for the education of (under)graduate students.