• Journal of Ginseng Research
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• 제9권1호
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• pp.9-14
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• 1985

The aerial parts, stem diameter, stem length, Petiole length, leaf length and leaf width were investigated to estimate coefficient of variability in ginseng at 2 to 4 years grown under the conventional and improved shadings. C.V values of characters such as stem length, petiole length, leaf length and leaf width were decreased with increasing the plant age, while that of steam diameter was increased. C.V. values of aerial part characters were higher in conventional shading than in improved shading, and the variance of c.v. was not significant when above 20 plants were investigated.

• Journal of Forest and Environmental Science
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• 제32권3호
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• pp.280-290
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• 2016

Stem diameter variability is an essential inventory result that provides useful information in forest management decisions. Little has been done to explore the modelling potentials of standard deviation (SDD) and coefficient of variation (CVD) of diameter at breast height (dbh). This study, therefore, was aimed at developing and testing models for predicting SDD and CVD in stands of Pinus caribaea Morelet (pine) in south west Nigeria. Sixty temporary sample plots of size $20m{\times}20m$, ranging between 15 and 37 years were sampled, covering the entire range of pine in south west Nigeria. The dbh (cm), total and merchantable heights (m), number of stems and age of trees were measured within each plot. Basal area ($m^2$), site index (m), relative spacing and percentile positions of dbh at $24^{th}$, $63^{rd}$, $76^{th}$ and $93^{rd}$ (i.e. $P_{24}$, $P_{63}$, $P_{76}$ and $P_{93}$) were computed from measured variables for each plot. Linear mixed model (LMM) was used to test the effects of locations (fixed) and plots (random). Six candidate models (3 for SDD and 3 for CVD), using three categories of explanatory variables (i.e. (i) only stand size measures, (ii) distribution measures, and (iii) combination of i and ii). The best model was chosen based on smaller relative standard error (RSE), prediction residual sum of squares (PRESS), corrected Akaike Information Criterion ($AIC_c$) and larger coefficient of determination ($R^2$). The results of the LMM indicated that location and plot effects were not significant. The CVD and SDD models having only measures of percentiles (i.e. $P_{24}$ and $P_{93}$) as predictors produced better predictions than others. However, CVD model produced the overall best predictions, because of the lower RSE and stability in measuring variability across different stand developments. The results demonstrate the potentials of CVD in modelling stem diameter variability in relationship with percentiles variables.

• 한국작물학회지
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• 제24권3호
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• pp.81-84
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• 1979

인삼변이계통의 선발에 필요한 기초자료를 얻고저 자경종, 황숙종, 미국종의 일년생에 대하여 여러 가지 농경형질의 변이를 조사하였던 바 그 결과를 요약하면 다음과 같다. 1. Panax quinquefolium이 Panax ginseng에 비하여 모든 형질의 변이가 큰 경향이었다. 2. Panax ginseng에 있어서는 자경종이 황숙종보다 형질변이가 크게 나타났다. 3. Panax ginseng, Panax quinquefolium 공히 경장, 엽장, 근장 등의 형질은 변이가 큰 반면에 경직경, 근직경 등의 형질은 비교적 적게 변화하였다.

• 농업과학연구
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• 제24권1호
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• pp.6-10
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• 1997

초장, 엽수, 경수, 경직경, 엽장, 엽폭, 근경생산량을 평가하기위하여 수집 한 94 clone은 경수와 근경생산량에서 유용한 변이를 보여주었다. 초장, 엽수, 엽장, 엽폭, 경직경은 약간의 변이가 관찰되었다. 작물학적 특성간의 단순상관은 근경생산량과 정의 상관을 보여주었고 엽수, 초장, 경직경은 근경생산량과 고도의 정의 상관을 보여주었다. 경로계수분석을 통하여 경수, 엽수, 경직경순으로 근경생산에 직접효과를 준다는 결과를 얻을 수 있었다. 엽수를 통한 초장의 간접효과가 가장 크게 나타났고, 엽수를 통한 엽장, 엽폭과 경직경을 통한 초장, 엽장, 엽폭에서도 간접효과가 관찰되었다. 선발의 관점에서 볼 때, 초장, 엽수, 경수와 같은 특성들은 좋은 유전형을 선발하기에 적합하다고 여겨진다.

• 한국작물학회지
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• 제45권4호
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• pp.245-250
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• 2000

This study was conducted to analyze the responses of some agronomic traits to the different cultural environments and relations among the agronomic traits for selecting sesame varieties with higher cultural stabilities. The indexes for stability parameters measured were coefficient of variability, heritabilities, genetic correlations and path coefficients of agronomic traits according to locations and years in Korea. The heritabilities of agronomic traits showed different by locations and years. Number of seeds per capsule and 1000 seeds weight showed higher heritabilities, but stem length and seed weight per plant showed relatively lower heritabilities. Average heritabilities of some agronomic traits in 1998 were comparatively higher than those of 1999. Of six areas, Jinju area showed biggest coefficient of yield variability in 1998-1999. Iksan and Taegu areas showed higher heritabilities in 1998, but Iksan and Jinju areas showed lower heritabilities in 1999. Genetic correlations were slightly higher than corresponding phenotypic correlations. Stem length showed positive genetic correlation with the number of capsules per plant, and seed weight per plant and the number of capsule per plant showed positive genetic correlation with seed weight per plant. On the analysis of path coefficients, stem length and number of capsules effected highly on grain yield. Great regional variations were observed on the effects of agronomic traits on grain yield. Higher direct effects of stem length on grain yield were observed at Suwon, Chungwon, Taegu, Jinju and Naju areas, but in Iksan area was observed higher direct effect of the number of capsules per plant on grain yield in 1998. In 1999, higher direct effect of stem length on grain yield was observed at Chungwon and Suwon areas. Iksan and Taegu areas were also observed higher direct effect of the number of capsule per plant on grain yield.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2015년도 학술발표회
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• pp.180-180
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• 2015

Weather radar has been widely used in measuring precipitation and discharge and predicting flood risks. The radar rainfall estimate has one of the essential problems in terms of uncertainty and accuracy. Previous study analyzed radar errors to reduce its uncertainty or to improve its accuracy. Furthermore, a recent analyzed the effect of radar error on rainfall-runoff using spatial error model (SEM). SEM appropriately reproduced radar error including spatial correlation. Since the SEM does not take the time dependence into account, its time variability was not properly investigated. Therefore, in the current study, we extend the SEM including time dependence as well as spatial dependence, named after Spatial-Temporal Error Model (STEM). Radar rainfall events generated with STEM were tested so that the peak runoff from the response of a basin could be investigated according to dependent error. The Nam River basin, South Korea, was employed to illustrate the effects of STEM on runoff peak flow.

• The Plant Pathology Journal
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• 제35권6호
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• pp.553-563
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• 2019

Investigations related with factors influencing root and crown rot are rare and mainly related to farming practice and soil management. The main objective of this study was to examine broader range of factors influencing stem-base infestation of winter wheat in the field conditions. The effect of spatial distribution of infected plants on disease index (DIs) assessments was also investigated. Analysis of factors influencing DIs of crown rot of wheat demonstrated significant influence of the growing seasons (P < 0.001) and extreme fluctuations in winter temperatures (P < 0.001). In addition to that, localities together with their interaction with the growing season also significantly influenced DIs (P < 0.001). Aggregation of infected plants influenced variability of DI estimations, and it was pointed out that more extensive investigation should be conducted on broad range of DI in order to establish sampling method giving uniform sampling precision. Fusarium graminearum was shown to be predominant Fusarium species in Serbia (72.6%) using sequence-characterized amplified region analysis. Interestingly F. oxysporum was isolated in higher frequencies (27.4%) than it was reported in the literature. Given that there were no reports on the diversity of Fusarium species causing crown rot of wheat in Serbia, this study presents first report on this important subject. It also indicated that more attention should be focused on combined effects of abiotic and biotic factors influencing stem-base infestation of winter wheat. This knowledge will contribute to better understanding of factors influencing root and crown rot of wheat which would ensure sustainable disease management in the future.

• Journal of the Korean Wood Science and Technology
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• 제33권1호통권129호
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• pp.21-28
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• 2005

중부 지방의 조림지에서 생육된 30년생의 일본잎갈나무(낙엽송)에 대하여 지상고별로 원반을 채취해 수를 중심으로 남측과 북측 부위의 조재 및 만재에 대해 가도관 길이와 폭, 마이크로피브릴 경각 및 압축, 휨, 충격 강도를 조사했다. 가도관의 길이와 폭에 있어 남측과 북측간에는 측정된 대부분 부위에서 차이가 없는 것으로 나타났다. 남측과 북측간의 마이크로피브릴 경각과 강도 역시 측정된 대부분 부위에서 차이가 없는 것으로 나타났다. 남측과 북측 부위간의 접선방향 수축율과 강도에 차이가 드러나지 않은 것은 남측과 북측간의 마이크로피브릴 경각사이에 차이가 없는 점에 기인하는 것으로 생각되었다.

• 한국농림기상학회지
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• 제9권3호
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• pp.203-208
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• 2007

본 연구에서는 동시에 여러 지점을 측정할 수 있는 open flow 시스템을 이용하여 소나무 줄기에서 발생하는 호흡을 겨울과 여름 두 시기에 측정하였다. 연구결과, 줄기의 목부조직에서 호흡속도($R_{stem}$)는 겨울에 $0.25-0.55{\mu}mol\;m^{-2}s^{-1}$, 여름에 $1.25-1.63{\mu}mol\;m^{-2}s^{-1}$의 범위를 나타냈다. 시기별 측정된 수목(15개체)간 $R_{stem}$의 변화성은 변동계수로 나타낼 수 있으며, 그 결과 여름과 겨울이 모두 23%로 시기에 따른 차이를 보이지 않았다. 이러한 변동계수 값에 근거하면 $R_{stem}$ 이 95% 신뢰수준에서 실제 값과의 차이가 10%와 20%보다 적기 위해서는 샘플링 수가 각각 최소 24개와 6개가 필요한 것으로 확인되었다. 또한 겨울과 여름의 온도와 개체간 평균 $R_{stem}$의 상관관계에서, $Q_{10}$ 값은 겨울이 1.49, 여름이 1.45로 계절간에 큰 차이를 나타내지 않았다. 그러나 $R_{20}$(줄기 온도 $20^{\circ}C$일 때의 $R_{stem}$)은 겨울($0.61{\mu}mol\;m^{-2}s^{-1}$)보다 여름($1.23{\mu}mol\;m^{-2}s^{-1}$)이 두 배 정도 컸다.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2001년도 제2회 생물정보 워크샵 (DNA Chip Bioinformatics)
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• pp.97-115
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• 2001

cDNA microarray technology allows the monitoring of expression levels for thousands of genes simultaneously. Many statistical analysis tools become widely applicable to the analysis of cDNA microarray data. In this talk, we consider a two-way ANOVA model to differentiate genes that have high variability and ones that do not. Using this model, we detect genes that have different gene expression profiles among experimental groups. The two-way ANOVA model is illustrated using cDNA microarrays of 3,800 genes obtained in an experiment to search for changes in gene expression profiles during neuronal differentiation of cortical stem cells.