• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.1
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• pp.112-121
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• 2007

Grain filling is a crucial factor that determines grain yield in crops since it is the final process directly associated with crops' yield performance. Grain filling process can be characterized by the interaction of rate and duration of grain filling. This study was conducted, using 16 temperate japonica rice genotypes, with aims to (1) seek variations in grain filling duration and rate on area basis, (2) compare the contribution of grain filling duration and rate to grain yield, and (3) examine the influence of temperature and solar radiation for effective grain filling on grain yield in relation to grain filling duration and rate. Grain filling rate and duration exhibited highly significant variations in the ranges of $20.7{\sim}46.3\;g\;m^{-2}d^{-1}\;and\;11.2{\sim}35.5$ days, respectively, depending on rice genotypes. Grain yield on unit area basis was associated positively with grain filling duration but negatively with grain filling rate. Grain filling rate and duration were negatively correlated with each other. Final grain weight increased linearly with the rise in both cumulative mean temperature and cumulative solar radiation for effective grain filling. Higher cumulative mean temperature and cumulative solar radiation for effective grain filling were the results of longer grain filling duration, but not necessarily higher daily mean temperature and daily solar radiation for effective grain filling. Grain filling rate demonstrated an increasing tendency with the rise in daily mean temperature for effective grain filling but their relationship was not obviously clear. It was concluded that grain filling duration, which influenced cumulative mean temperature and cumulative solar radiation for effective grain filling, was the main factor that determined grain yield on unit area basis in temperate Japonica rice.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.681-687
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• 2002

The cumulative, shrinkage plastic strains and their distributions in the weld joint after completion of the welding process determine welding-induced distortion. Although the weldment undergoes many complex physical and metallurgical changes during welding, only the material plastic temperature range and its cooling history below this temperature range influence the [mal state of the cumulative shrinkage plastic strains. In addition, for structural welds, these plastic strains are uniform, except in the arc start and stop regions, along the weld. Therefore, the plastic strain-based "inherent shrinkage model" is effective and accurate to describe welding-induced distortion. This paper presents the theoretical background and numerical verification of this root cause.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.157-165
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• 1997

In this experiment, there is a purpose to analysis the relationship of feature of compressive strength after fixing of remarkable element under the condition of initial curing temperature. According to this experiment, we get to the fallow result. In case of highest curing temperature, 3-day-strength become high but last revelation of strength become low among the condition of initial curing temperature, the highest curing temperature have an effect on revelation of strength by the application of cumulative temperature, we can get the shape of revelation of strength.

• Journal of the Korean Data and Information Science Society
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• v.27 no.4
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• pp.969-977
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• 2016

Climate change affects the growth of crops which were planted especially in fields, and it becomes more important to use climate data to predict the yields of the major vagetables. The variation of the crop products caused by climate change is one of the significant factors for the discrepancy of the demand and supply, and leads to the price instability. In this paper, using a panel regression model, we predicted the garlic yields with the weather conditions of different regions. More specifically we used the panel data of the several climate variables for 15 main garlic production areas from 2006 to 2015. Seven variables (average temperature, average maximum temperature, average minimum temperature, average surface temperature, cumulative precipitation, average relative humidity, cumulative duration time of sunshine) for each month were considered, and most significant 7 variables were selected from the total 84 variables by the stepwise regression. The random effects model was chosen by the Hausman test. The average maximum temperature (January), the cumulative precipitation (March, October), the cumulative duration time of sunshine (April, October) were chosen among the variables as the significant climate variables of the model

• Journal of Bio-Environment Control
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• v.17 no.2
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• pp.124-131
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• 2008

To investigate main air temperature factors correlated to difference of fruit characteristics according to cultivating areas, fruit and air temperature characteristics of eight cultivating areas of 'Fuyu' persimmon were analyzed by principle components and multiple regression analysis. The first principal components extracted from 16 air temperature factors was annual mean temperature, mean temperature during October, annual mean minimum extreme temperature, mean temperature during growing period, and so forth. The second principal components was mean temperature during May and June and so forth. And cumulative contribution was 91.4%. The five of eight cultivating area had clearly the difference of main factors or the correlated direction among cultivating areas. In multiple regression analysis between the extracted main factors and fruit characteristics, fruit hight were highly correlated with mean temperature during growing period ($X_8$) and cumulative temperature ($X_6$), and the regression equation was $Y=150.55-5.375X_8+ 0.014X_6(r^2=0.843)$. Also this regression equation was affected by mean minimum temperature during growing period, cumulative temperature, and mean temperature during August. Fruit diameter was negatively correlated with mean temperature during growing period, flesh browning rate and Hunter a value of peel color were positively correlated with mean minimum temperature during growing period and annual minimum air temperature, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.4
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• pp.348-351
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• 1985

Air temperature and its inference in rice planting were briefly analyzed to compare the difference in agricultural climatic condition in Korea and Japan. The results were as follows: 1. The mean air temperatures of August showed similar range at the same latitude in both countries but those of Korea in January were much lower than of Japan showing the greater annual range. 2. The daily fluctuations of air temperature during spring and autumn in Korea were greater than in Japan, and it was prominent in the daily minimum temperature. At the same cumulative temperature for maturing of rice plant, the cumulative cooling temperature lower than the certain marginal temperature, say $12^{\circ}C$ or $13^{\circ}C$, was greater in Korea than in Japan. Therefore, in analysis of temperature data relating to rice cropping, authors suggested that the cumulative cooling temperature be considered.

• Journal of the Korean Geographical Society
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• v.43 no.3
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• pp.312-323
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• 2008

The purpose of this paper is to analyze thermal sensation which is measured by human physioclimatic reactions in South Korea. Relationships between Temperature-Humidity Index(THI) and human thermal sensation scale are derived from a questionnaire, which investigates degree of volunteer's thermal sensation with respect to each biometeorological condition. Analyses of these empirical relationships make it possible to calculate thermal sensational indices and to classify bioclimatic types for individual weather stations based on long-term(1971-2000) averages of monthly temperature and humidity data. A generalized annual physioclimatic maps for each Annual Cumulative Thermal Sensation Index for the 68 stations are constructed to show men tend to feel in various areas. The Monthly thermal sensations are affected by latitude, altitude, orographic effects and systems of airmasses. The Annual Cumulative Thermal sensations are increasing towards northern areas and inland, and that the major factors are largely derived from cold stress in winter. The Annual Physioclimatic Types are grouped 8 climatic types(M, ES, M-ES, M-S, W-ES, C-ES, C-M, C-M-ES) according to climatic stress. Results of this study can be applied for evaluation of thermal environment in our daily activities, and for searching relevant sports training-sites, climatherapy etc.

• Journal of Bio-Environment Control
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• v.19 no.3
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• pp.165-170
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• 2010

This experiment was conducted to select the affected main factors on growth and fruit characteristics of 'Fuyu' persimmon (Diospyros kaki Thunb.) in 25 factors of air temperature factors in Naju. Mean air temperature, cumulative temperature and days for March and April of 25 factors were the highest annual variation. Number of the first and second principal components extracted from 25 air temperature factors were 14 and 3 factors related with mean temperature for annul and April, and cumulative contribution of these was 52.2%. Also the affected years by the first principal components were 1990, 1980 and 1986. Annual standard deviation on leafing, flowering and maturing date were 4.0~6.7 days range, and flowering date and days from leafing to flowering had the highest coefficient of variation. Annual variation of days from flowering to maturing date was affected by greatly mean air temperature and days of cumulative temperature in October, days from March 1 to leafing date was affected by cumulative temperature for growing period, days from leafing to flowering date was affected by mean air temperature in April. Annual variation of fruit weight was affected by mean air temperature for March and October.

• Journal of Advanced Research in Ocean Engineering
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• v.1 no.2
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• pp.106-114
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• 2015

In the fabrication of offshore oil and gas facilities, the significance of dimension control is growing continuously. But, it is difficult to determine the deformation of the structure during fabrication by simple lab tests due to the large size and the complicated shape. Strain-boundary method (a kind of shrinkage method) based on the shell element was proposed to predict the welding distortion of a structure effectively. Modeling of weld geometry in shell element is still a difficult task. In this paper, a concept of imaginary temperature pair is introduced to handle the effect of geometric factors such as groove shape, plate thickness and pass number, etc. Single pass imaginary temperature pair formula is derived from the relation between the groove area and the FE mesh size. By considering the contribution of each weld layer to the whole weldment, multi-pass imaginary temperature is also derived. Since the temperature difference represents the distortion increment, cumulative distortion curve can be drawn by integrating the temperature difference. This curve will be a useful solution when engineers meet some problems occurred in the shipyard. A typical example is shown about utilization of this curve. Several verifications are conducted to examine the validity of the proposed methodology. The applicability of the model is also demonstrated by applying it to the fabrication process of the heavy ship block. It is expected that the imaginary temperature model can effectively solve the modeling problem in shell element. It is also expected that the cumulative distortion curve derived from the imaginary temperature can offer useful qualitative information about angular distortion without FE analysis.

• Fisheries and Aquatic Sciences
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• v.3 no.2
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• pp.78-82
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• 2000

The influence of daily water temperature changes on chemiluminescent (CL) response of phagocytes, plasma glucose level and mortality in cultured gray mullet (Mugil cephalus) was investigated. Among three experimental temperature groups, the fish in group I and group II were maintained constantly at $27^{\circ}C$ and $29^{\circ}C$, respectively, and those in group III were suffered daily elevation of water temperature from $27^{\circ}C$ to $29^{\circ}C$ for 5 hours, then restored again to $27^{\circ}C$. After 1 week of maintaining at each experimental tank, the fish in group III showed significantly lower CL peak value (p < 0.01) and higher plasma glucose levels (p < 0.05) than those in group I and group II. The cumulative mortality of group III was $86.9\%$ within 3 days after being subjected to acute handling stress. On the other hand, the cumulative mortalities of group I and group II were $12.5\%$ and $19.2\%$, respectively. In conclusion, gray mullet farms, especially, in the vicinity of thermoelectric power plants should avoid stressing the fish during periods of high water temperature.