• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.E
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• pp.72-78
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• 1995

To support some knowledge in planning irrigation system, short or long-term irrigation scheduling or determining irrigation reservoir capacity, it is necessary to estimate peak irrigation requirements and seasonal distribution of water demands for various return periods. In this paper Dry Day Index and Probable Evapotranspiration were evaluated to decide seasonal consumptive use of paddy rice for a design year using several decades' daily rainfall data and 5 years'('82~'86) actual evapotranspiration data, respectively. To obtain Dry Day Index that is defined as the number of probable dry days for a given period, Slade unsymmetrical distribution function was adopted. Dry Day Index was analysed for 5 and 10-day intervals. Each of them was evaluated with return periods of 1, 3, 5, 10 and 20 year. Their singnificance was tested by X$^2$ method. Based on these values, the Probable Evaportanspiration, that is the average daily ET both in dry days and rainy days during a given period, was estimated. Crop coefficient was also determined by the modified Penman equation proposed by Doorenbos & Pruitt.

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.4
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• pp.81-89
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• 1989

This study is to determine seasonal consumptive use of water of a design year during growing period (June-September) for paddy rice in Suwon. To obtain Dry flay Index which is defined as the number of probable dry days occurring at a design year, Slade Partly Un- symmetrical Distribution Function was adopted. Dry Day Index was analysed with 5, 10 and 30 day-term. And each of them was evaluated with recurrence intervals of 1, 3, 5, 10 and 20 year using 49 years daily rainfall data('35-'83). Their singnificance were tested at 1% level by X$^2$ test. On the basis of these values, Probable Evapotranspiration (ET) which is the daily average ET for the sum of both ET on dry days and ET on rainy days were esti- mated using 5 years daily actual ET data(' 82-' 86). Their Crop Coefficients were also de- termined by the modified Penman equation(1977) proposed by Doorenbos & Pruitt.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.3
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• pp.3-15
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• 2008

North Korea is one of the vulnerable countries facing the threat of a drought, so that it is unavoidable to experience fatal damage when drought is occurred, and it is necessary to improve the drought response capability of water resources systems. However, it is still difficult to find research efforts for drought characteristics and drought management in North Korea. This study is to quantify drought duration and magnitude and to analyze drought characteristics in North Korea. In order to quantitatively identify historical drought conditions and to evaluate their variability, drought indices are commonly used. In this study, drought indices including dry-day index, deciles of normal precipitation, Phillips drought index, standardized precipitation index and Palmer drought severity index are calculated and compared monthly using the weather data for the twenty one meteorological stations in North Korea. The indices compared with the drought damage records that have reported from 1990 to present to understand how the indices can explain the drought. A comparative study was also conducted to evaluate the relative severity of the significant droughts occurred during 2000 and 2001 which were reported as the worst drought in North Korea. Drought indices calculated from this study demonstrated that those can be the effective tools in quantitatively evaluating drought severity and measures of drought. Thus it is recommended the distributed trend of drought be considered when the plan or measures for drought in North Korea are established.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.4
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• pp.485-492
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• 2011

The influence of high temperature on mammary cell turnover during the dry period is still unclear. The objective of this study was to investigate mammary cell turnover and p53 protein expression in the mammary tissue under high temperature conditions. Mammary gland biopsy samples from 8 dairy cows were obtained at 7, 25, 40, and 53 d during the dry period in summer or spring (n = 4, each season). Cell cycle, cell turnover, and p53 protein expression were analyzed by flow cytometry. During the dry period in summer, the percentage of mammary epithelial cells in the G0/G1 phase was the highest, but those in the S and G2/M phases were lower. However, the proportion of cells in the different stages of the cell cycle was not significantly different among the different biopsy time points, except in the G2/M phase. Under different temperature conditions, the cells were significantly different in their apoptotic rate and proliferation index; moreover, the tendencies of these indicators to change significantly differed. In general, the samples under high temperature conditions showed significantly lower apoptotic rates and proliferation indices. Under high temperature conditions, the apoptotic rate and proliferation index were the lowest (2.17% and 3.26%, respectively) at day 40, and the highest at day 53 (3.67% and 4.61%, respectively). However, under normal temperature conditions, the values of these indicators were the lowest (7.60% and 5.54%, respectively) at day 7, and almost the highest at day 25 (12.85% and 6.47%, respectively). Moreover, p53 protein expression was significantly higher under high temperature conditions than under normal temperature conditions, except at day 25. The level of p53 protein was the lowest (13.10%) under high temperature conditions at day 25, but was the highest (26.07%) under normal temperature conditions. Our findings suggest that high temperature delayed the G2/M phase of the cell cycle and the cell turnover rate, but remarkably increased p53 protein expression. Thus, the results indicate that high temperature extends the recovery period of mammary epithelial cells.

• Journal of Korean Society for Quality Management
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• v.47 no.3
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• pp.497-508
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• 2019

Purpose: The purpose of this study is to overcome limitations of conventional studies that to predict Baltic Dry Index (BDI). The study proposed applications of Artificial Neural Network (ANN) named Long Short-Term Memory (LSTM) to predict BDI. Methods: The BDI time-series prediction was carried out through eight variables related to the dry bulk market. The prediction was conducted in two steps. First, identifying the goodness of fitness for the BDI time-series of specific ANN models and determining the network structures to be used in the next step. While using ANN's generalization capability, the structures determined in the previous steps were used in the empirical prediction step, and the sliding-window method was applied to make a daily (one-day ahead) prediction. Results: At the empirical prediction step, it was possible to predict variable y(BDI time series) at point of time t by 8 variables (related to the dry bulk market) of x at point of time (t-1). LSTM, known to be good at learning over a long period of time, showed the best performance with higher predictive accuracy compared to Multi-Layer Perceptron (MLP) and Recurrent Neural Network (RNN). Conclusion: Applying this study to real business would require long-term predictions by applying more detailed forecasting techniques. I hope that the research can provide a point of reference in the dry bulk market, and furthermore in the decision-making and investment in the future of the shipping business as a whole.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.3
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• pp.27-41
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• 2017

The purpose of this study is to diagnose the possibility of future drought expression by late March dryness in rice paddy areas using Terra MODIS NDVI (Normalized Difference Vegetation Index). We tested the degree of dryness by comparing the 2000-2015 average NDVI with yearly NDVI, which we name DCI (Dry Condition Index). The 16-day interval DCIs from March 6 to May 25 were evaluated with spatio-temporal expression of South Korea. In particular, we find that the DCI for April 7 (March 23 to April 7) offered reasonable prediction of paddy dryness during drought years. The April 7 DCI value for dry conditions ranged from 0.04 to 0.08 while the DCI for normal conditions ranged from -0.04 to 0.01. The DCI can be one of the indicators used to evaluate the dryness of rice paddy areas at the beginning of the spring season.

• Journal of the Korean Society of Tobacco Science
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• v.23 no.1
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• pp.5-11
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• 2001

Experiments were conducted to evaluated the sucker control efficiency of several suckercides and their combinations for flue-cured tobacco in Korea. In 1999, Flumetralin(Prime+, P+), Butralin(B), Fatty alcohol(FA, n-decanol 85%), pottasium salt of maleic hydrazide(MH), tank mix of MH with P+ (MH·P+), and another tank mix of MH with FA(MH·FA) were applied after topping, respectively, then sucker number and sucker dry weight were investigated on the 30th and 50th day from treatment. Sucker number and dry weight were significantly lowered by P+, B, FA and MH·P+ applications compared with those of MH and MH·FA for both investigated periods. A significant reduction in sucker number and dry weight was observed in P+, B, and MH·P+ applications. FA treatment was not so much effective in sucker control as P+. In 1999 and 2000, several suckercides and tank mixes of their combinations were applied first at button stage and second after topping, respectively, to compare the effects of sucker control on yield, price index and chemical components of cured leaves. Compared to the standard method of FA 30x at button stage followed by MH40x application after topping(FA 30x + MH 40x), sucker number and dry weight decreased by [FA 30x (or P+ 1%] or [FA 30x(or B 1.5%) + MH 60x·B 1.5%] treatments, even at reduced MH levels. But yield, price index and chemical components of cured leaves were not differed among treatments.

• Journal of Acupuncture Research
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• v.29 no.5
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• pp.39-50
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• 2012

Objectives : The purpose of this study was to identify the effects of self-acupressure on the visual health of college students. Methods : A nonequivalent control group pretest-posttest design was used. Participants were determined by OSDI(ocular surface disease index) and the Schirmer test, they were assigned to an experimental group of 22 and control group of 22. The experimental group participated in self-acupressure, which were practiced 2 times a day, 5 days a week for 4 weeks. Results : Scores of ocular surface disease index, Schirmer test and ocular fatigue were significantly better in the experimental group after the intervention compared to the control group. Conclusions : The result indicate that self-acupressure is an effective nursing intervention for improving the dry eye syndrome and decreasing ocular fatigue in college students.

• Journal of Ginseng Research
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• v.39 no.1
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• pp.7-13
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• 2015

Background: Many patients with glaucoma have difficulty using antiglaucoma eye drops because of dry eye symptom. In this prospective, randomized, double-blind, placebo-controlled study, we evaluated the effect of Korean Red Ginseng on dry eye syndrome in patients with glaucoma treated with antiglaucoma eye drops. Methods: Forty-nine participants were allocated to the Korean Red Ginseng (3 g/day; n = 24) or placebo (n = 25) groups for 8 weeks. Tear film stability, fluorescein corneal staining, conjunctival hyperemia, tear production, grade of meibomian gland dysfunction, and dry eye questionnaire (Ocular Surface Disease Index) were evaluated at baseline and on completion of the treatment. Results: Almost all patients displayed dry eye symptoms and signs at baseline. After the 8-week intervention, Korean Red Ginseng supplementation significantly improved the tear film stability and total Ocular Surface Disease Index score, as compared to placebo (p < 0.01). Conclusion: Korean Red Ginseng supplementation may provide an additional treatment option for dry eye and patients with glaucoma using antiglaucoma eye drops.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.5
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• pp.29-43
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• 2020

Thermal environment of city is getting worse due to severe urban heat island caused by climate change and urbanization. The cooling effect of street tree is regarded as a effective way to ameliorate the urban heat environment. The effect is largely made up of shadow formation and transpiration. This study aims to identify how the transpiration affects the discomfort index by analyzing comprehensive impact of the transpiration on the air temperature and relative humidity. The changes in the amount of transpiration, air temperature, and relative humidity were estimated for Seogyo-dong area which has a lot of floating population in Seoul, at 2 p.m. in dry day in July and August. On average, the transpiration of the street tree decreased the temperature 0.3℃ and increased the relative humidity 2.6% in an hour. As a result of these changes in temperature and humidity, the discomfort index rose mostly(0.036 on average). It was always get rise especially on the day when the discomfort index was above 80(0.05 on average). However, compared with the significant change in temperature and humidity, the variation of the discomfort index itself was very slight(up to 0.107). Therefore, the effect of transpiration by the street trees might not be effective in the planning to improve the thermal environment(especially on the day when the discomfort index is high). It is necessary to select the species of trees and planting location considering the cooling effect of shade formation synthetically.