• 제목/요약/키워드: Arithmetic average

검색결과 182건 처리시간 0.024초

유역 및 기상상태를 고려한 Clark 단위도의 매개변수 평가: 1. 대표 호우사상의 선정 및 분석 (Evaluation of the Clark Unit Hydrograph Parameters Considering Basin and Meteorologic at Conditions : 1. Selection and Analysis of Representative Storm Events)

  • 유철상;김기욱;이지호
    • 한국수자원학회논문집
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    • 제40권2호
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    • pp.159-170
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    • 2007
  • 본 연구에서는 관측자료에 나타난 Clark 단위도의 매개변수를 검토하고 그 변동성을 평가하였다. 여기에는 강우-유출과정에 영향을 미치는 유역 및 기상 특성인자들을 확률밀도함수를 적용하여 정량화하고, 이를 바탕으로 하여 관측 강우-유출 사상 중 평균적인 사상을 분류하며, 마지막으로 선별된 강우-유출 사상에 대해 Clark 단위도의 평균적인 매개변수를 유도하는 과정이 포함된다. 이러한 과정을 통해 얻은 결과를 정리하면 다음과 같다. (1) 유역을 대표하는 유출특성(즉, 집중시간 및 저류상수)의 결정에는 관측 강우-유출사상의 수가 어느 정도 확보된다고 하더라도 여전히 높은 불확실성을 피하기 힘들다. (2) 집중시간의 경우는 그 분포가 상당히 왜곡된 형태여서 단순한 산술평균은 상당히 왜곡된 추정치를 제시할 가능성이 높다. 즉, 정규분포에 근거한 평균값인 산술평균은 더 이상 집중시간에 대한 대표값의 역할을 하지 못한다. 오히려 최빈값의 경우가 보다 대표성을 갖는 것으로 판단된다. 반면에 저류상수의 경우는 거의 대칭인 분포를 하고 있으므로 산술평균이 어느 정도의 대표성을 확보한다고 판단할 수 있다. 본 연구의 대상유역의 경우 집중시간은 대략 7시간 정도가, 저류상수는 대략 22시간 정도가 적절한 것으로 판단된다.

반도체 제조 근로자의 극저주파 자기장 노출 평가 (Occupational Exposure of Semiconductor Workers to ELF Magnetic Fields)

  • 정은교;김갑배;정광재;이인섭;유기호;박정선
    • 한국산업보건학회지
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    • 제22권1호
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    • pp.42-51
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    • 2012
  • Objectives: To compare the exposure level of extremely low frequency (ELF) magnetic fields among semiconductor workers, shipyard welders and office workers. Methods: To measure the ELF magnetic field concentration, EMDEX LITE (Enertech, USA) were used and monitored for eight hours continuously. Five companies handling the electric and magnetic field (EMF) source were investigated, which the exposure groups were classified into three groups: semiconductor workers, welders, and office workers. Welder group was chosen as a high exposed group and office group as a low exposed group. Results: The arithmetic mean (${\pm}SD$) and geometric mean (GSD) of personal exposure level of semiconductor workers were 0.73 (${\pm}1.33$) ${\mu}T$, 0.43 (2.88) ${\mu}T$, respectively. The ceiling value ranged between 0.18 and 123.2 ${\mu}T$. Welders were exposed high with the arithmetic mean value of 3.46 (${\pm}\;13.46$) ${\mu}T$ and geometric mean value of 0.45 (4.70) ${\mu}T$, respectively, and ceiling value range of 75.5~129.6 ${\mu}T$. The exposure levels of office workers were low compared to other exposed groups; the arithmetic mean 0.05 (${\pm}0.13$) ${\mu}T$, geometric mean 0.03 (2.38) ${\mu}T$ and ceiling value range 0.37~3.35 ${\mu}T$. This study revealed statistically significant differences of the mean ELF magnetic field exposure doses among three groups (p < 0.01). Conclusions: The average ELF magnetic field exposure doses of semiconductor workers were much higher than those of office workers in control group, but were lower than those of welders in high exposure group.

간호대학생의 자아상태와 대응양상과의 관계 연구 (Study on the Ego states and Coping Style of Nursing Students)

  • 원정숙
    • 여성건강간호학회지
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    • 제8권4호
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    • pp.608-618
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    • 2002
  • The purpose of this study is to analyze the type of ego states and stress coping style on female college students who are in the course of nursing study. This study is performed in the view of Transactional Analysis and designed to scrutinize descriptive correlations between the type of ego states and stress coping style. The subject is consists of 144 freshmen and sophomore, 138 junior and senior students group, who are students of K nursing college located in Seoul. The sampling investigation period is on Sept. 14, 2002 to Oct. 26, 2002. The measuring instrument used for Transactional Analysis ego state is 50 items Ego-gram research paper devised by Dusay(1997). For studying coping style, Folkman & Lazarus's measurement(1984) was adopted, which is translated and modified by Han, and Oh,(1990). Statistic average and standard deviation were generated by using SPSS PC+, t-test and Pearson correlation. The results were as follows: 1) In the type of ego states on both groups(lower group : freshmen, sophomore upper group : junior, senior) indicated the arithmetic apex NP(maximum value), then the point A was high and the data made a down slope to point AC. In the comparison to type of ego states between two groups, only at point CP, the data value of upper year students represented higher than that of lower year ones by C(t=2.28, p=.023). In the psychological energy level of ego states, both groups indicated average level.2) Stress coping style of whole students were highly and affirmatively dedicated to research. Consecutive consequences follow like this(high to low) : the central point of problem, search for social support, hopeful aspect and indifference. Especially hopeful aspect(t=.67, p=.05), relaxation of tension(t=-2.16, p=.03) made significant difference each other in the view of arithmetic calculation 3) While verifying coping style in terms of ego states level between lower and upper students group, In type CP, high level ego states group indicated significant difference on stress coping style area than low leveled group and made such sequences as the central point of problem, hopeful aspect, search for social support, positive interest and relaxation of tension. In type NP, sequences such as the central point of problem, search for social support, positive interest and relaxation of tension were emerged with little differences. In type A, the central point of problem, positive interest and relaxation of tension. In type FC, hopeful aspect, search for social support, positive interest and relaxation of tension. In type AC, hopeful aspect and indifference were derived significantly different(p<.05). 4) In the aspect of relation between ego states and coping style, type CP presented the central point of problem and relaxation of tension, type NP presented positive interest, search for social support and the central point of problem, type A showed the central point of problem, positive interest and relaxation of tension, type FC showed relaxation of tension, positive interest, search for social support, indifference and the central point of problem, type AC showed hopeful aspect, indifference and the central point of problem. All the sequence shown above had high-to-low procedure and represented static relations each other(p<.05).

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RAPD를 이용한 한국 포도 품종의 계통유연관계 분석 (Analysis of Genetic Relationships of Grapevine Cultivars (Vitis ssp.) in Korea Using RAPD Markers)

  • 유기열;조강희;신일섭;김정희;허성;노정호;김현란
    • 한국육종학회지
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    • 제41권4호
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    • pp.437-443
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    • 2009
  • 본 실험은 29개 포도 품종(Vitis spp.)의 효율적 유전학적 유연관계를 분석함으로써 포도품종 육성을 위한 기초자료로 이용하고자 RAPD(Random Amplified Polymorphic DNA) 방법을 이용하여 분석하였다. 총 60개의 프라이머를 이용하여 558개의 다형성 밴드를 얻었다. 획득된 다형성 밴드를 사용하여 UPGMA(unweighted pair-group method arithmetic average) clustering 분석 결과, 포도 품종은 유사도 0.588을 기준으로 나누었을 때 6개 그룹으로 분류되었다. 가장 높은 유사도 값(0.980)을 나타낸 것은 국내 육성 품종인 "흑보석"과 "수옥" 품종이었고, 가장 낮은 유사도 값(0.404) 을 나타낸 것은 프랑스 품종인 "S. 9110"과 일본 품종인 "Super Hamburg"로 나타났다. "Super Hamburg"는 첫 번째 그룹(I)에 구성되었다. 두 번째 그룹(II)은 "원교 라-23"과 "Muscat Hamburg" "Tano Red" 그리고 "탄금추"가 포함되어 있었다. 세 번째 그룹(III)은 "Alden" "원교 라-21", "원교 라-30" 그리고 "Dutchess" 품종이 속해있었다. 네 번째 그룹(IV)은 14개 포도 품종이 포함되었으며("흑구슬", "흑보석", "수옥", "원교라-29", "원교 라 -22", "거봉", "Pione", "홍이두", "Golden Muscat", "진옥", "두누리", "캠벨얼리", "Delaware", "Schuyler"), 거봉 계열의 5 품종과 캠벨얼리 계열의 4 품종 그리고 이들의 교배조합에 사용된 품종이 포함되어 있었다. 다섯 번째 그룹(V) 3개 품종으로 구성되었다(홍단', "탐나라", "홍이슬", "Himrod seedless"). 여섯 번째 그룹(VI)은 "청수"와 모본인 "S. 9110"이 포함되었다. 본 실험의 결과는 DNA 수준에서 포도의 교배육종에 이용할 양친의 선정이나 육종연구에 기초 자료가 될 수 있을 것으로 기대된다.

Comparative Analysis of ICT Accessibility and Usability of Korean Students Based on PISA 2015 and 2018 Data

  • Kim, Kapsu;Min, Meekyung
    • International Journal of Internet, Broadcasting and Communication
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    • 제12권1호
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    • pp.73-80
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    • 2020
  • The OECD surveys the questionnaire on the background of ICT every three years since 2003. In this study, we compare and analyze the changes in ICT accessibility and ICT usability of Korean students in 2015 and 2018 using the ICT background data of OECD PISA. ICT accessibility refers to the degree of access to ICT equipment at school or at home. There are 10 items of accessibility surveys at schools used by PISA, and 11 items at home. ICT usability refers to how much ICT equipment is used at or outside of school for learning or non-learning purposes. There are ten items for surveying usability at school, and twenty-four items for surveying usability outside of school. In the analysis of this study, the arithmetic mean of the items is used. As a result, Korean students' accessibility at school improved from 25.48% in 2015 to 40.40% in 2018, and from the lowest group in 2015 to below-average group in 2018. In terms of students' usability at school, we analyzed the percentage of students who use the ICT equipment 'almost every day' and the students who use it 'everyday'. Both 2015 and 2018 are among the lowest. Accessibility at home is higher in 2018 than in 2015, and belongs to the average group of OECD countries in 2018. ICT Usability for learning purposes outside of school is the lowest group in both 2015 and 2018. ICT Usability outside of school for non-learning purposes is in the average group of OECD countries. As a result of this study, we can see that Korea's digital literacy education is weak compared to other OECD countries. Prior to education about the Fourth Industrial Revolution, investment in digital literacy education is needed.

Lossless Compression for Hyperspectral Images based on Adaptive Band Selection and Adaptive Predictor Selection

  • Zhu, Fuquan;Wang, Huajun;Yang, Liping;Li, Changguo;Wang, Sen
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권8호
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    • pp.3295-3311
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    • 2020
  • With the wide application of hyperspectral images, it becomes more and more important to compress hyperspectral images. Conventional recursive least squares (CRLS) algorithm has great potentiality in lossless compression for hyperspectral images. The prediction accuracy of CRLS is closely related to the correlations between the reference bands and the current band, and the similarity between pixels in prediction context. According to this characteristic, we present an improved CRLS with adaptive band selection and adaptive predictor selection (CRLS-ABS-APS). Firstly, a spectral vector correlation coefficient-based k-means clustering algorithm is employed to generate clustering map. Afterwards, an adaptive band selection strategy based on inter-spectral correlation coefficient is adopted to select the reference bands for each band. Then, an adaptive predictor selection strategy based on clustering map is adopted to select the optimal CRLS predictor for each pixel. In addition, a double snake scan mode is used to further improve the similarity of prediction context, and a recursive average estimation method is used to accelerate the local average calculation. Finally, the prediction residuals are entropy encoded by arithmetic encoder. Experiments on the Airborne Visible Infrared Imaging Spectrometer (AVIRIS) 2006 data set show that the CRLS-ABS-APS achieves average bit rates of 3.28 bpp, 5.55 bpp and 2.39 bpp on the three subsets, respectively. The results indicate that the CRLS-ABS-APS effectively improves the compression effect with lower computation complexity, and outperforms to the current state-of-the-art methods.

간호대학생의 죽음에 대한 의식 변화 연구 -호스피스 간호 학습 전.후 비교- (A Study on Change in Death Orientation of College Student Nurses -comparison of pre and post hospice care class-)

  • 백설향;이미애;김인홍
    • 기본간호학회지
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    • 제8권3호
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    • pp.357-365
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    • 2001
  • Purpose: The purpose of this study was to identify the death orientation of college student nurses and to evaluate the effectiveness in death orientation of a class on 'hospice care'. this was done by investigating the difference between the death orientation before and after the class. Method: The instrument used in this Investigation was the death orientation scale developed by Thorson and Powell (1988). The subjects of the study were the 47 college student nurses in a 'hospice care' class. The research was carried out between March 2, 2001, when the class began, and June 21, 2001 when the class ended The collected data were examined using arithmetic mean, percentage, t-test, ANOVA. Result: The results of the study are as follows : 1. The average death orientation score of the subjects before the class was 2.80. 2. There were a significant difference in the death orientation scores before and after the class (p<0.001). Before the class, 'hospice care', the students had an average score of 2,80. Their average score decreased to 2.55 after the class. Of 25 death orientation items on the scale, 14 items decreased significantly after the class as compared to before the class. 3. According to personal attributes (religion. the existence of religion, the experience of a death in recently) of subjects, there were no significant statistical differences in death orientation (p>0.05). Conclusion: This study showed that a class on hospice care was effective in changing the death orientation of student nurses.

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매립지 토양층의 수리경사와 주 흐름 방향의 변동특성 (Variation Characteristics of Hydraulic Gradient and Major Flow Direction in the Landfill Soils)

  • 김태영;강동환;김성수;권병혁
    • 한국환경과학회지
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    • 제18권3호
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    • pp.315-323
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    • 2009
  • Hydraulic gradient of the landfill soils is estimated by Devlin (2003) method, and its variation characteristics from rainfall and permeability of the aquifer material are analyzed. The study site of 18 m $\times$ 12 m is located in front of the Environment Research Center at the Pukyong National University, and core logging, slug/bail test and groundwater monitoring was performed. The sluglbail tests were performed in 9 wells (except BH9 well), and drawdown data with elapsed time for bail tests were analyzed using Bouwer-Rice and Hvorslev methods. The average hydraulic conductivity estimated in each of the test wells was ranged $1.991{\times}10^{-7}{\sim}4.714{\times}10^{-6}m/sec$, and the average hydraulic conductivity in the study site was estimated $2.376{\times}10^{-6}m/sec$ for arithmetic average, $1.655{\times}10^{-6}m/sec$ for geometric average and $9.366{\times}10^{-7}m/sec$ for harmonic average. The permeability of landfill soils was higher at the east side of the study site than at the west side. Groundwater level in 10 wells was monitored 44 times from October 2 to November 7, 2007. The groundwater level was ranged 1.187$\sim$1.610 m, and the average groundwater level range in each of the well showed 1.256$\sim$1.407 m. The groundwater level was higher at the east side than at the west side of the study site, and this distribution is identify to it of hydraulic conductivity. The hydraulie gradient and the major flow direction for 10 wells were estimated 0.0072$\sim$0.0093 and $81.7618{\sim}88.0836^{\circ}$, respectively. Also, the hydraulic gradient and the major flow direction for 9 wells were estimated 0.0102$\sim$0.0124 and $84.6822{\sim}89.1174^{\circ}$, respectively. The hydraulic gradient of the study site increased from rainfall (83.5 mm) on October 7, causing by that the groundwater level of the site with high permeability was higher. The hydraulic gradient estimated on and after October 16 was stable, due to almost no rainfall. Thus, it was confirmed that the variation of the hydraulic gradient in the landfill soils was controlled by the rainfall.

인공지능 기반 멀티태스크를 위한 비디오 코덱의 성능평가 방법 (Evaluation of Video Codec AI-based Multiple tasks)

  • 김신;이예지;윤경로;추현곤;임한신;서정일
    • 방송공학회논문지
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    • 제27권3호
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    • pp.273-282
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    • 2022
  • MPEG 내 VCM 그룹은 머신을 위한 비디오 코덱을 표준화하는 것으로 목표로 하고 있다. VCM 그룹은 객체 탐지, 객체 분할, 객체 추적 등 3가지의 머신비전 태스크를 포함한 데이터 세트와 데이터 세트 별 기준 데이터인 Anchor를 제공하고 있으며, 평가 템플릿을 이용하여 후보 기술군과 Anchor의 압축 대비 머신비전 성능을 비교할 수 있다. 하지만 성능 비교는 머신비전 태스크 별로 분리하여 수행되고 있으며, 다수의 머신비전 태스크에 대한 성능 평가를 수행할 수 있는 비트스트림을 생성할 수 있는 데이터는 별도로 제공하고 있지 않다. 본 논문에서는 인공 지능 기반 멀티 태스크를 위한 비디오 코덱의 성능 평가 방안에 대해 제안한다. 하나의 비트스트림의 크기 척도인 픽셀 당 비트수(BPP, Bits Per Pixel) 와 각 태스크의 정확도 결과인 Mean Average Precision(mAP)를 기반으로 산술 평균, 가중 평균, 조화 평균 등 총 3가지의 멀티 태스크 성능 평가 지표를 제안하며 mAP 결과를 기반으로 성능 결과를 비교하고자 한다. 멀티 태스크에서 태스크 별 mAP 결과 값의 범위의 차이가 있을 수 있으며 차이로 인해 생길 수 있는 성능 평가와 관련된 문제를 방지하고자 정규화한 mAP 기반 멀티 태스크 성능 결과를 산출하고 평가하고자 한다.

Genetic diversity, relationships and demographic history of the small yellow croaker, Larimichthys polyactis (Pisces: Sciaenidae) from Korea and China inferred from mitochondrial control region sequence data

  • Kim, Jin-Koo;Kim, Yeong-Hye;Kim, Mi-Jung;Park, Jung-Youn
    • Animal cells and systems
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    • 제14권1호
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    • pp.45-51
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    • 2010
  • Genetic variation was surveyed at the mitochondrial control region (766bp) to test for the presence of genetic stock structure in the small yellow croaker, Larimichthys polyactis from the Yellow and East China Seas. Individuals of the small yellow croaker could not be distinguished on the basis of its location, as demonstrated using the neighbor-joining (NJ) method, unweighted pair-group method, arithmetic average (UPGMA) and the minimum spanning network (MSN). Analysis of molecular variance revealed no significant differences among collections of the small yellow croaker taken from the four locations (two locations each in Korea and China). Neutrality tests and a mismatch distribution analysis indicated that this species has recently expanded. Our findings suggest either that the small yellow croaker has a high migration capability that enables it to overcome the effects of genetic drift, or that this species expanded relatively recently and has not yet had sufficient time to differentiate.