• Title/Summary/Keyword: 상관계

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A Estimation and Analysis of Characteristics for Hazen-Williams C Value of Water Pipe System (상수관로 유속계수 산정 및 특성 분석)

  • Kim, Kyoung Oh;Kim, Se Min;Park, Yung Ki
    • Proceedings of the Korea Water Resources Association Conference
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    • 2019.05a
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    • pp.239-239
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    • 2019
  • 상수도시설 중 배수관망시설은 해당 지역의 영향을 민감하게 받는 시설이므로 설계시 해당시설의 특성을 충분히 고려해야 한다. 배수시설은 설치된 해당지역에 따라 그 특성이 매우 다르기 때문에, 설계지표 또한 해당 도시마다 다르게 설정될 수 있다. 도시의 규모가 크거나, 그 특성이 해당 구역에 따라 다른 경우에는 같은 도시의 경우라도 대상구역에 따라 다른 지표를 사용하는 경우도 있다. 따라서 이런 상수도관망의 설계 및 관리를 위해서는 장기간 현장여건에 맞는 관측자료를 통한 정밀한 수리분석이 요구되며 국내의 경우 일반적으로 Hazen-Williams 공식을 사용하고, 이때 관내면의 마찰손실계수 C는 유속계수라 한다. 이러한 유속계수는 상수관로의 물리적 특성을 나타내며 관로 내의 흐름해석, 펌프 및 관로의 설계, 최적 운영 방안, 통수능력 및 관 노후도 평가 등에 사용되거나 영향을 미치는 중요한 요소라 평가되고 있다. 또한 다수의 현장 관측 자료를 확보하여도 분기 구간과 펌프 및 밸브 등으로 인한 손실 등의 오차가 발생하므로 유속계수 산정 시 발생되는 많은 오차들을 줄여 보다 신뢰성 있는 유속계수를 산정해야 하고, 현장 관측 자료를 이용하여 유속계수를 산정하기 어려운 구간에 대해서는 관망해석 모델링을 통하여 결정하고 있다. 본 연구에서는 전주권 광역상수도의 계통 특성에 맞는 관로의 유속계수를 결정하기 위해 관리주체에서 기존에 설치한 수압계와 유량계 및 관망도를 이용하여 기초자료를 수집하고 Hazen-Williams 공식을 이용하여 유속계수를 산정하였다. 계산된 상수관로 유속계수는 전주시의 10개 계통에서 최소 107.06, 최대 145.02, 평균 127로 계산되었으며, 유속계수에 영향을 미치는 물리적 요소들의 관계를 파악하고자 상관성 분석 실행하였다. 그 결과 관경과 경과년수의 상관계수 R은 0.011 관경과 유속계수의 상관계수는 -0.009로 두변수간의 상관성이 거의 없고, 경과년수와 유속계수의 상관계수는 -0.776로 음의 상관성을 갖는 것으로 분석되었다. 이와 같이 제시한 유속계수는 해당 지역의 참고자료나 기준으로서 활용할 수 있을 것으로 판단되며 비 대상 지역에서도 현장자료가 부족한 곳의 유속계수를 산정할 경우 보다 신뢰성 있게 유속계수를 산정할 수 있는 방법을 제시하고자 한다.

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Correlation analysis for viewpoint of hologram and stereo image (홀로그램과 스테레오 영상의 시점에 대한 상관성 분석)

  • Kim, Woo-Suk;Kim, Dong-Wook;Seo, Young-Ho
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2018.06a
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    • pp.202-204
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    • 2018
  • 본 논문에서는 부분 홀로그램의 중심점과 카메라의 이동에 따라 생성되는 시점 영상들의 상관성을 분석하였다. 같은 기준에서의 실험을 위하여, 물체의 실제 크기 및 시점간 거리 등의 파라미터를 조정하였으며, 카메라의 수평이동과 부분 홀로그램의 중심점이 좌, 우로 이동된 결과를 생성하는 실험을 진행하였다. 결과를 기반으로, 서로 다른 광학계와 생성방법을 통하여 생성된 임의의 시점 영상들의 상관성을 분석한다.

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Egg Quality Traits and Their Correlations in 12 Strains of Korean Native Chicken (토종닭 12계통 난질의 일반능력 및 상관관계 분석)

  • Kim, Kigon;Kwon, Il;Choo, Hyojun;Park, Byoungho;Cha, Jaebeom
    • Korean Journal of Poultry Science
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    • v.47 no.3
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    • pp.181-188
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    • 2020
  • In this study, sixteen egg quality traits, including egg weight, albumen weight, yolk weight, eggshell weight, albumen weight ratio, yolk weight ratio, eggshell weight ratio, yolk color, eggshell color, egg height, egg width, shape index, albumen height, Haugh unit, eggshell thickness, and eggshell strength were investigated in 12 strains of Korean native chicken using 600 eggs from birds at 38 weeks of age. Results showed that the Korean White Leghorn F strain had the highest egg weight of 62.7 g and the lowest (47.5 g) was observed in the Korean native chicken W strain. The Haugh unit was significantly different between strains. The mean Haugh unit for Korean native chicken ranged between 84.2 (L strain) and 76.0 (F strain), with an overall average of 79.9. Eggshells were the thinnest in Korean Rhode Island Red C and D strains (0.342 mm), whereas the highest eggshell thickness (0.393 mm) was observed in the Korean White Leghorn K strain. Korean Rhode Island Red C and D strains had low egg strength compared to that of other strains. Korean Cornish and Korean native chicken showed significant differences in egg quality traits between strains within breeds. Positive correlation coefficients were observed between egg weight and egg quality traits. The traits for color showed zero or low correlations with most egg quality traits. Egg shape index showed no correlation with most egg quality traits. Albumen height and the Haugh unit showed a positive correlation with albumen traits. Eggshell strength showed a positive correlation with eggshell traits.

Relationships among Emotional Labor, Fatigue, and Musculoskeletal Pain in Nurses (간호사의 감정노동, 피로 및 근골격계 통증의 관계)

  • Lee, Eun-Yeon;Kim, Ju-Sung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.1
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    • pp.351-359
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    • 2017
  • This study examined emotional labor, fatigue, and musculoskeletal pain in hospital nurses. The study sample included 235 hospital nurses. The data were collected by questionnaire and analyzed with descriptive statistics, t-test, ANOVA, Scheffe test, Pearson's correlation coefficients, and multiple regression.The average emotional labor score was 3.27, and of fatigue was 2.04. The musculoskeletal pain score was 4.43. Emotional labor and fatigue are significantly positively associated with musculoskeletal pain(r=.180, p=.006; r=.278, p<.001). Emotional labor was positively associated with the degree of fatigue(r=.353, p<.001). The significant predictors of musculoskeletal pain for nurses were physical fatigue(${\beta}=.324$, p<.001) and gender(female)(${\beta}=.171$, p=.009), explaining 13.7% of the variance in musculoskeletal pain(F=16.271, p<.001). The results suggest that engaging in emotional labor related to nursing tasks increases the risks of fatigue and musculoskeletal pain. Therefore, it is important to develop a management program to relieve the emotional labor, fatigue, and prevent musculoskeletal pain for clinical nurses.

Hydration Rate of Milled Rice (백미의 수분 흡수 속도)

  • Kim, Sung-Kon;Han, Ki-Young;Park, Hong-Hyun;Chae, Je-Cheon;Ree, Jung-Haeng
    • Applied Biological Chemistry
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    • v.28 no.2
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    • pp.62-67
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    • 1985
  • Hydration rate of 35 Japonica and 24 J x Indica rice varieties at $23^{\circ}C$ was investigated and an attempt was made for a tentative classification of milled rice into six groups based on hydration rate. Each rice variety had characteristic value for hydration rate. In general, J x Indica rice hydrated at a faster rate than Japonica rice. Hydration rate was negatively correlated with the ratio of length to width of rice grain. No correlation was found between hydration rate and protein, amylose, surface area, volume or initial water grain.

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Correlation Algorithm for High-Precision Measurement in FM-CW Radar Level Meters (FM-CW 레이더 거리계의 비트 신호 스펙트럼 상관성을 이용한 고정밀 측정 알고리듬)

  • Kim, Jeong-Mok;Lim, Zong-Soo;Chun, Joong-Chang;Kim, Tae-Soo;Shim, Jae-Ryun;Park, Wee-Sang
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.38 no.4
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    • pp.38-44
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    • 2001
  • In this paper, for the microwave level meter based on the FM-CW radar, we analyze the spectrum correlation of beat signals and propose a measurement algorithm using the theory. For industrial applications, level meters must have high precision, which requires a good linearity of VCO. But, in practice, it is very complicated or very expensive to make VCO linear enough to be acceptable in the industrial field. We propose a measurement algorithm using the fact that there exists a peak in the spectrum correlation of beat signals when range difference is sufficiently small. This makes it possible to determine the range difference in a precise manner even using a practical VCO. We present some experimental results to show the validity of this algorithm.

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The Factors Affecting the Perceived Symptoms of Temporomandibular Disorders in Academic High School Students (일부 인문계 고등학생들의 측두하악장애 자각증상 관련 영향요인)

  • Ji, Min-Gyeong
    • Journal of Convergence for Information Technology
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    • v.11 no.10
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    • pp.215-222
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    • 2021
  • The purpose of this study was to analyze the factors affecting the awareness of temporomandibular disorders in high school students and to provide basic data for the development of easy-to-access program to help the management of temporomandibular disorders. For data collection, convenience sampling was performed among academic high school students in Daejeon and North Jeolla Province to complete a self-administered questionnaire from December 1 to 30, 2019. The statistical analysis was conducted by t-test, one-way ANOVA, and Pearson correlation. Stepwise multiple regression analysis was conducted. Oral parafunctional habits were positively correlated with trait anxiety and both of them were positively correlated with the perceived symptoms of temporomandibular disorders. The most influential factors on the awareness symptoms of temporomandibular disorders in high school students were oral parafunctional habits, health habits, and trait anxiety. It is necessary to make positive communication and intervention, which meets high school age, in coping well with anxiety and managing oral parafunctional habits and apply an oral health promotion program that involves socio-psychological efforts to prevent them.