• Korean Journal of Soil Science and Fertilizer
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• v.40 no.5
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• pp.429-434
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• 2007

This study was conducted to estimate site productivity of Quercus acutissima and Quercus mongolica by four forest climatic zones. We used site environmental variables (28 geographical and pedological factors) and site index as a site productivity indicator from nation-wide 23,315 stands. Based on multiple regression analysis between site index and major environmental variables, the best-fit multivaliate models were made by each species and forest climatic zone. Most of site index prediction models by species were regressed with seven to eight factors, including altitude, relief, soil depth, and soil moisture etc. For those models, three evaluation statistics such as mean difference, standard deviation of difference, and standard error of difference were applied to the test data set for the validation of the results. According to the evaluation statistics, it was found that the models by climatic zones and species fitted well to the test data set with relatively low bias and variation. Also having above middle of site index range, total area of productive sites for the two Quercus spp. estimated by those models would be about 6% of total forest area. Northern temperate forest zone and central temperate forest zone had more productive area than southern temperate forest zone and warm temperate forest zone. As a result, it was concluded that the regressive prediction with site environmental variables by climatic zones and species had enough estimation capability of forest site productivity.

• The Korean Journal of Community Living Science
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• v.22 no.3
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• pp.445-454
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• 2011

This study was performed on 5 prehypertensive male participants to investigate the effects of the clothing program for improving the vascular compliance on heat tolerance. The clothing program means the alternate stimulation of the temperature using clothes. The participants wore two different garments with $1.5^{\circ}C$ difference in the temperature inside clothing in a climatic chamber ($18.8{\pm}0.2^{\circ}C$, $38{\pm}3%RH$) alternately for 4 weeks. Heat tolerance tests were conducted in the climatic chamber of $35.2{\pm}0.5^{\circ}C$, $54{\pm}3%RH$ before and after the clothing program. The results were as follows. The $\overline{T}$sk, Tr and heart rate were lower in the post test than in the pre test (p<.01). The whole body and local sweat rates as well as systolic and diastolic blood pressures had reduced the tendencies in the post test. Participants felt less wet and more comfortable in the post test than in the pre test(p<.01). These results showed that the clothing program through the alternate stimulation of the temperature positively affected the improvement of heat tolerance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.3
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• pp.246-268
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• 2019

Soybean [Glycine max (L.) Merr.] is a species of legume native to East Asia. The interactions between climatic conditions and genetic characteristics are known to affect the agricultural performance of soybean. Therefore, the present investigation was conducted to identify the main elements affecting the agricultural performances of 11 soybean varieties/lines from China [Harbin ($45^{\circ}12^{\prime}N$), Yanji ($42^{\circ}53^{\prime}N$), Dalian ($39^{\circ}30^{\prime}N$), Qingdao ($36^{\circ}26^{\prime}N$)] and the Republic of Korea [Suwon ($37^{\circ}16^{\prime}N$), and Jeonju ($35^{\circ}49^{\prime}N$)]. The days to flowering (DTF) of soybeans with the e1-nf and e1-as alleles and the E1e2e3e4 genotype, except in 'Keumgangkong', 'Tawonkong', and 'Duyoukong', were relatively short compared to those of soybeans with other alleles. Although DTF of the soybeans was highly correlated with all climatic conditions [negative: precipitation, average temperature (AVT), accumulated temperature; positive: day-length (DL)], days to maturity and 100-seed weight of the soybeans showed no significant correlation with any climatic conditions. The soybeans with a dominant Dt1 allele, except 'Tawonkong', had the longest stem length (STL). Moreover, STL of the soybeans grown in the test fields showed a positive correlation with only DL; however, the results of our chamber test that was conducted to complement the field tests showed that STL of soybean was positively affected by AVT and DL. Although soybean yield (YLD) showed positive correlations with latitude and DL (except L62-667, OT89-5, and OT89-6), the response of YLD to the climatic conditions was cultivar-specific. Our results show that DTF and STL of soybeans grown in six different latitudes are highly affected by DL, and AVT and genetic characteristic also affect DTF and STL.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.473-473
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• 2011

Group method of data handling neural networks model (GMDH-NNM) is used to estimate daily reference evapotranspiration (ETo) using limited climatic variables such as max temperature ($T_{max}$), min temperature ($T_{min}$), mean wind speed ($W_{mean}$), mean relative humidity ($RH_{mean}$) and sunshine duration (SD). And, for the performances of GMDH-NNM, it consists of training and test performances, respectively. The training and test performances are carried out using daily time series data, respectively. From this research, we evaluate the impact of GMDH-NNM for the modeling of the nonlinear time series data. We should, thus, construct the credible data of the daily ETo data using GMDH-NNM, and can suggest the methodology for the irrigation and drainage networks system. Furthermore, this research represents that the strong nonlinear relationship such as ETo modeling can be generalized using GMDH-NNM.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.154-154
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• 2022

The frequency of natural disasters, including floods and drought events, driven by climate change has increased in recent times. Investigating the climate regimes and the roles of climate variables are indispensable to forestall future climate change-related disasters. This study compares the variability of two popular and widely used climate indices i.e., the United Nations Environment Programme (UNEP) aridity index and the Modified De-Martonne (MDM) index to assess the trend of climate change in the Chungcheong provinces of South Korea. The trend of annual and monthly climate indices was conducted using a non-parametric Mann-Kendall test and Kolmogorov-Smirnov normality test with daily climate data of 48 years (1978-2020) from 10 synoptic stations. The findings indicate that UNEP and MDM indices had a wet climate regime for the annual trend, with the UNEP index indicating a relatively humid trend of 60% humid, 20% semi-arid, and 10% sub-humid for the 48-years study period. However, the MDM index showed a high frequency of a severe wet climatic condition followed by the semi-arid condition. The months of July and August had the highest occurring frequency of the wet climatic condition (90%) for both UNEP and MDM indices. Comparing the two provinces, Chungnam showed a relatively wetter climatic condition using the UNEP index, while the MDM index indicated no significant regional difference in climate regime between the two provinces. The Kolmogorov-Smirnov normality test showed that all the 10 stations are normally distributed for monthly climate conditions at a 5% significant level in the two provinces except five stations for UNEP index and four stations for MDM index in the month of January.

• Journal of Korean Society of Forest Science
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• v.97 no.2
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• pp.135-139
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• 2008

Seed production and germination could be influenced by some factors. The picking time and climate factors are regarded as the elements to obtain sound seeds. We have observed the seed productivity and germination of seeds from trees of Chamaecyparis obtusa selected in a clonal seed orchard. Depending on picking time, various shapes from liquid material, something jellied to the fully matured one were observed. Germination aspects varied throughout the test days. After 20days of seeding in a glass petri-dish, germinal apparatuses appeared from the all seeds which had been picked from after at the end of August. The highest germination rate of about 30% was observed from the seeds picked from $20^{th}$ of September and $10^{th}$ of October. Seed production was about two times higher in 2005 than in 2006 and the average germination rate was also higher in 2005. We have also analyzed the effects of climatic factors about two consecutive years on seed productivity. Among the climatic factors, monthly sum of temperature and of precipitation were the main factors for maturation of Chamaecyparis obtusa seeds.

• Journal of the Korean Solar Energy Society
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• v.27 no.4
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• pp.157-165
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• 2007

Typical meteorological data is fundamental to computer simulation introduced for environment-friendly architecture designs. Therefore, in order to improve accuracy of computer simulation, typical meteorological data should be established. By examining how to choose typical meteorological data, this study selected the optimized weight factor for TRY where weighting factor was not clearly set. As a result, the same weighting factor was applied to each climatic element and TRY data where the weight factor was applied could have the distribution very similar to measurement data. The weighting factor is considered to reflect geographical characteristics of Seoul and applied climatic elements.

• Microbiology and Biotechnology Letters
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• v.49 no.2
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• pp.249-254
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• 2021

The study of the impact of weather on viral respiratory infections enables the assignment of causality to disease outbreaks caused by climatic factors. A better understanding of the seasonal distribution of viruses may facilitate the development of potential treatment approaches and effective preventive strategies for respiratory viral infections. We analyzed the incidence of human mastadenovirus infection using real-time reverse transcription polymerase chain reaction in 9,010 test samples obtained from Cheonan, South Korea, and simultaneously collected the weather data from January 1, 2012, to December 31, 2018. We used the data collected on the infection frequency to detect seasonal patterns of human mastadenovirus prevalence, which were directly compared with local weather data obtained over the same period. Descriptive statistical analysis, frequency analysis, t-test, and binomial logistic regression analysis were performed to examine the relationship between weather, particulate matter, and human mastadenovirus infections. Patients under 10 years of age showed the highest mastadenovirus infection rates (89.78%) at an average monthly temperature of 18.2℃. Moreover, we observed a negative correlation between human mastadenovirus infection and temperature, wind chill, and air pressure. The obtained results indicate that climatic factors affect the rate of human mastadenovirus infection. Therefore, it may be possible to predict the instance when preventive strategies would yield the most effective results.

• Journal of Applied Reliability
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• v.18 no.2
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• pp.95-103
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• 2018

Purpose: Environment test aim to validate the guarantee of required capability of materiel against various environment conditions which exposed during materiel life-cycle. In this paper, environment test design procedure and tailoring guideline for Korean peninsula and periphery climate are proposed. Methods: To design tailoring guideline, climate data which are regarding Korean peninsula and periphery regions provided from Korea Meteorological Administration (KMA) and National Climatic Data Center (NCDC) are used. Conclusion: For effective environment test, it is important that environment test have to design in considering environment conditions during materiel life-cycle. It is concluded that the high temperature test level can be softer than the test criteria in MIL-HDBK-310, however, the low temperature test level will be expected to be $2{\sim}6^{\circ}C$ harsher than MIL-HDBK-310.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.2
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• pp.89-97
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• 2012

This study was conducted to estimate forest site productivity and productive areas of Quercus acutissima and Quercus mongolica using environmental factors including climatic variables. Using the data set from digital forest site map and forest climatic map, a total of 42 environmental variables were regressed on site index for developing the best site index equations for Quercus acutissima and Quercus mongolica. Five to six environmental factors by species were selected as independent variables in the best site index equations. For the site index equations, three evaluation statistics (i.e., mean difference, standard deviation of difference, and standard error of difference) were applied to the test data set for the validation of the results, The site index equations fitted well to the test data set with relatively low bias and variation. As a result, it was concluded that the site index equations by species were well capable of estimating site quality. Finally, based on the site index equations, the productive areas by species were estimated by applying GIS technique to the digital forest maps. In addition, the distribution of productive areas by species was illustrated.