• Title/Summary/Keyword: grand mean

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Seasonal Variation of Cosmic Ray Intensity Observed by the Oulu Neutron Monitor

  • Jeong, Jaesik;Oh, Suyeon
    • Journal of Astronomy and Space Sciences
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    • v.37 no.3
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    • pp.165-170
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    • 2020
  • Muons and neutrons are representative secondary particles that are generated by interactions between primary cosmic ray particles (mostly protons) and the nuclei of atmospheric gas compounds. Previous studies reported that muons experience seasonal variations because of the meteorological effects of temperature. The intensity of neutrons has a typical modulation with various periods and reasons, such as diurnal and solar variation or transient events. This paper reports that cosmic ray particles, which were observed by neutron monitors, have seasonal variations using the daily data at the Oulu neutron monitor. To eliminate the effects of solar activity across time, the daily data were normalized by two different transformations: transformations with respect to the grand mean and yearly mean. The data after transformation with respect to the yearly mean showed more statistical stability and clear seasonal variations. On the other hand, it is difficult to determine if the seasonal variation results from terrestrial effects, such as meteorological factors, or extraterrestrial effects, such as the position of the Earth in its orbit of revolution.

Grand Average in MEG and Crude Estimation of Anatomical Site (뇌자도에서 전체 평균과 이를 이용한 해부학적 위치 추정)

  • Kwon H.;Kim K.;Kim J. M.;Lee Y. H.;Park Y. K.
    • Journal of Biomedical Engineering Research
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    • v.25 no.6
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    • pp.575-580
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    • 2004
  • In this work, a method is presented to find an anatomical site of a current source crudely in a standard brain using grand average of MEG data. Minimum norm estimation algorithm and truncated singular value decomposition were applied to calculate the distributed sources that can reproduce the measured signals. Grand average over all subjects was obtained from the transformed signals, which would be detected in a standard sensor plane by the obtained distributed current sources. In the simulation study, it was shown that the localized dipole using the grand average is consistent with the mean location of localized dipoles of all subjects within several mm even with large inter-individual differences of sensor positions. This result suggests that the mean location of low level signal source can be estimated as a dipole source in grand average and it was confirmed in the localization of the current source of N100m. when the localized dipole is registered on a standard brain. This result also suggests that the activity region obtained from grand average can be crudely estimated on a standard brain using the source location of the N100m as a reference point.

A Survey of food procurement practices in hospital dietetics -Assessment of the level of processing for purchased foods- (병원급식의 구매관리 실태조사 -구매 식품의 가공정도 평가를 중심으로-)

  • 신익자;남순란;곽동경
    • Korean journal of food and cookery science
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    • v.4 no.1
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    • pp.65-73
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    • 1988
  • Food procurement practices were assessed in 31 general hospital's dietetics in terms of the level of processing for purchased food. The level of processing before purchase by the institution was noted by a numerical value. a Food Processing Index (FPI). Labor productivity measured in terms of labor minutes per meal served averaged 12.59 minutes. Responsible persons for procurement practices were mostly dietitians, but effective purchasing methods as well as inventory control techniques were not fully systematized. Dietetic directors anticipate the large increase in the use of convenience foods in the future mainly due to the improved labor productivity, and also a highly increasing demand for completely pre-prepared food items (FPI 3). The grand mean of FPI scores for purchased foods in surveyed hospitals was 3.34, which indicates partially pre-prepared to completely pre-prepared food items. Significant negative correlation was found between the grand mean of FPI scores and the number of beds in a hospital.

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Predictability for Heavy Rainfall over the Korean Peninsula during the Summer using TIGGE Model (TIGGE 모델을 이용한 한반도 여름철 집중호우 예측 활용에 관한 연구)

  • Hwang, Yoon-Jeong;Kim, Yeon-Hee;Chung, Kwan-Young;Chang, Dong-Eon
    • Atmosphere
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    • v.22 no.3
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    • pp.287-298
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    • 2012
  • The predictability of heavy precipitation over the Korean Peninsula is studied using THORPEX Interactive Grand Global Ensemble (TIGGE) data. The performance of the six ensemble models is compared through the inconsistency (or jumpiness) and Root Mean Square Error (RMSE) for MSLP, T850 and H500. Grand Ensemble (GE) of the three best ensemble models (ECMWF, UKMO and CMA) with equal weight and without bias correction is consisted. The jumpiness calculated in this study indicates that the GE is more consistent than each single ensemble model. Brier Score (BS) of precipitation also shows that the GE outperforms. The GE is used for a case study of a heavy rainfall event in Korean Peninsula on 9 July 2009. The probability forecast of precipitation using 90 members of the GE and the percentage of 90 members exceeding 90 percentile in climatological Probability Density Function (PDF) of observed precipitation are calculated. As the GE is excellent in possibility of potential detection of heavy rainfall, GE is more skillful than the single ensemble model and can lead to a heavy rainfall warning in medium-range. If the performance of each single ensemble model is also improved, GE can provide better performance.

A Sudy on Mothers' and Grand Mothers' Picture Book Reading Behaviors with Young Children (영유아-어머니 및 영유아-할머니의 그림책 읽기 행동에 관한 연구)

  • Kwon, Heekyoung
    • Korean Journal of Childcare and Education
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    • v.13 no.2
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    • pp.133-147
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    • 2017
  • Objective: The purpose of this study was to examine the differences between mothers' and grand mothers' picture book reading behavior with children of ages 2 and 4. Methods: Participants were twenty 2 year olds and their mothers/grandmothers as well as twenty 4 year olds and their mothers/grandmothers. Forty pairs of children/mothers and children/grandmothers, respectively, were videotaped as they shared reading a picture book together. Data were analyzed with descriptive statistics, mean, standard deviation, and two-way ANOVA test. Results: Results indicated that mothers' and grandmothers' picture book reading behaviors were significantly different in verbal behavior. Mothers performed more explanation and questioning, while grandmothers performed more limitation, directing, and correcting. As far as non-verbal behavior is concerned, mothers used more physicalgestures, pointing, descriptive gestures, and imitative gestures, whereas grandmothers requested certain actions. Conclusion/Implications: These findings have implications for the importance of the mothers'/grandmothers' roles in shared picture book reading with the child.

Extent of linkage disequilibrium and effective population size of the Landrace population in Korea

  • Shin, Donghyun;Kim, Sung-Hoon;Park, Joowan;Lee, Hak-Kyo;Song, Ki-Duk
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.8
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    • pp.1078-1087
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    • 2018
  • Objective: The genetic diversity of the Landrace population, a representative maternal pig breed in Korea, is important for genetic improvement. Previously, the effective population size (Ne) has been used to infer the genetic diversity of a population of interest. In this study, we aimed to use single nucleotide polymorphism (SNP) data to characterize linkage disequilibrium (LD) and the Ne of the Korean Landrace population. Methods: We genotyped 1,128 Landrace individuals from three representative Korean major grand-grand-parent (GGP) farms using the Illumina PorcineSNP60 version2 BeadChip, which covers >61,565 SNPs located across all autosomes and mitochondrial and sex chromosomes. We estimated the expected LD and current Ne, as well as ancestral Ne. Results: In the Korean Landrace population, the mean LD ($r^2$) of 3.698 million SNP pairs was $0.135{\pm}0.204$. The mean $r^2$ decreased slowly with as the distance between SNPs increased, and remained constant beyond 3 Mb. According to the $r^2$ calculations, 8,085 of 3.698 million SNP pairs were in complete LD. The current Ne (${\pm}$standard deviation) of the Korean Landrace population is approximately 92.27 [79.46; 105.07] individuals. The ancestral Ne exhibited a slow and steady decline from 186.61 to 92.27 over the past 100 generations. Additionally, we observed more a rapid Ne decrease from the past 20 to 10 generations ago, compared with other intervals. Conclusion: We have presented an overview of LD and the current and ancestral Ne values in the Korean Landrace population. The mean LD and current Ne for the Korean Landrace population confirm the genetic diversity and reflect the history of this pig population in Korea.

Development of Hybrid Rice Facilitated by Cytoplasmic Genetic Male Sterility II. Responses of Korean Cultivars to the Chinese Cytoplasmic Genetic Male Sterile lines (웅성불임성을 이용한 수도잡종품종개발 II. 중공의 세포형질 유전적 웅성불임계통에 대한 몇가지 한국품종의 반응)

  • 허문회;김홍열;조윤희
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.29 no.3
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    • pp.227-231
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    • 1984
  • Chinese CGMS (Cytoplasmic-Genetic Male Sterility) is being transfered to Korean cultivars which will be used as CGMS maintainers. These maintainer lines along with the Chinese CGMS lines and their maintainer lines were crossed with another group of Korean cultivars which will be used as the fertility restorers, and their yield heterosis were examined. The yield heterosis was calculated as high as 113.0-221.1 % in terms of heterosis (F$_1$/Midparent) with the grand mean of 150.5%, and, 86.1-179.8% in terms of heterobeltiosis (F$_1$/better parent) with the grand mean of 125.3%. Among the female parent groups, Chinese mainteiners were the highest following by Chinese MS lines and the Korean maintainers were the lowest. Heterobeltiosis of yield components were 92.7%, 120.0%, 103.0% and 112.0% for number of panicles/unit area, number of grains/panicle, fertility per cent and 1000 grain weight, respectively. Path-coefficients of yield components to the yield were calculated. The highest one was number of grains per panicle ranging 0.8073-0.8649 followed by the 1000 grain weight ranging 0.2000-0.5032. The grain yield ratios to the grand mean were calculated in terms of combining ability. It was highest with the Chinese maintainers followed by Chinese MS lines and The Korean maintainers were lowest. This facts bring cautions to the breeding efforts to transfer the Chinese CGMS in to Korean maintainers.

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Application of Analysis of Means(ANOM) for Design of Experiment (실험계획법에서 평균분석(ANOM)의 응용)

  • Choi, Sung-Woon
    • Proceedings of the Safety Management and Science Conference
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    • 2008.04a
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    • pp.283-293
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    • 2008
  • Analysis of Means(ANOM) is a visualization tool for comparing several means to the grand mean like control chart type. This paper reviews five ANOM methods for continuous data such as ANOM, ANOME (ANOM for Treatment Effects), ANCON (Analysis of Contrasts), ANOMV (ANOM for Variance), ANOMC (ANOM for Correaltion). Three ANOM tools for discrete data such as ANOMNP (ANOM for Nonconforming Proportions), ANOMNC (ANOM for Nonconforming Unit), ANOMNPU (ANOM for Nonconfirmities Per Unit) are also developed.

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Multiscale Simulation for Adsorption Process Development: A Case Study of n-Hexane Adsorption on Activated Carbon (흡착공정 개발을 위한 다중규모 모사: 활성탄에서의 n-Hexane 흡착에 관한 사례연구)

  • Son, Hae-Jeong;Lim, Young-Il;Yoo, Kyoung-Seun
    • Korean Chemical Engineering Research
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    • v.46 no.6
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    • pp.1087-1094
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    • 2008
  • This article presents a multi-scale simulation approach starting from the molecular level for the adsorption process development, specifically, in n-hexane adsorption on activated carbon. A grand canonical Monte-Carlo(GCMC) method is used for the prediction of adsorption isotherms of n-hexane on activated carbon at the molecular level. Geometric effects and hydrodynamic properties of the adsorption column are examined by means of the two dimensional CFD(computational fluid dynamics) simulation. The adsorption isotherms from the molecular simulation and the axial diffusivity from the CFD simulation are exploited for the process simulation where the elution curve of n-hexane is obtained. For the first moment(mean residence time) of the pulse-response with respect to temperature and flowrate, the process simulation results obtained from this three-steps multiscale simulation approach show a good agreement with experimental data within 20% of maximum difference. The multi-scale simulation approach addressed in this study will be useful to accelerate the adsorption process development, while reducing the number of experiments required.

Variation of Solar, Interplanetary and Geomagnetic Parameters during Solar Cycles 21-24

  • Oh, Suyeon;Kim, Bogyeong
    • Journal of Astronomy and Space Sciences
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    • v.30 no.2
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    • pp.101-106
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    • 2013
  • The length of solar cycle 23 has been prolonged up to about 13 years. Many studies have speculated that the solar cycle 23/24 minimum will indicate the onset of a grand minimum of solar activity, such as the Maunder Minimum. We check the trends of solar (sunspot number, solar magnetic fields, total solar irradiance, solar radio flux, and frequency of solar X-ray flare), interplanetary (interplanetary magnetic field, solar wind and galactic cosmic ray intensity), and geomagnetic (Ap index) parameters (SIG parameters) during solar cycles 21-24. Most SIG parameters during the period of the solar cycle 23/24 minimum have remarkably low values. Since the 1970s, the space environment has been monitored by ground observatories and satellites. Such prevalently low values of SIG parameters have never been seen. We suggest that these unprecedented conditions of SIG parameters originate from the weakened solar magnetic fields. Meanwhile, the deep 23/24 solar cycle minimum might be the portent of a grand minimum in which the global mean temperature of the lower atmosphere is as low as in the period of Dalton or Maunder minimum.