• Journal of the Korean association of regional geographers
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• v.20 no.3
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• pp.334-343
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• 2014

The number of malaria cases has been undulating for the past 10 years in Korea since the reemergence of malaria in early 1990's. Considering the spatial variations of malaria incidence across the northmost border areas near the demilitarized zone (DMZ), the occurrence of the disease seems to be influenced by the natural and human environment in the region. Malaria is an infectious disease that is transmitted to humans by the bites of vector-mosquitoes that carry malaria parasites, and its incidence rate depends on specific climatic and sociodemographic factors. This study found that the spatial characteristics of malaria incidence have varied depending on relative proportions of mosquito habitats, distance between mosquito habitats and human residence, the physical and sociodemographic environments of the city by urbanization, and local topography.

• Journal of Korean Society on Water Environment
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• v.37 no.2
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• pp.114-127
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• 2021

Water pollution in the lower reaches of the Namhan River is getting worse due to drought and a decrease in water quantity due to climatic changes and hence is affecting the water quality of Paldang Lake. Accordingly, we have used a water quality index (WQI) and statistical analysis in this study to identify the characteristics of the water quality in the lower reaches of the Namhan River, the main causes of water pollution, and tributaries that need priority management. Typically, 10 items (WT, pH, EC, DO, BOD, COD, SS, T-N, T-P, and TOC) were used as the water quality factors for the statistical analysis, and the matrix of data was set as 324 × 10·1. The correlation analysis demonstrated a strong correlation between Chemical Oxygen Demand (COD) and T-P with a high statistical significance (r=0.700, p<0.01). Furthermore, the result of principal component analysis (PCA) revealed that the main factors affecting the change in water quality were T-P and organic substances introduced into the water by rainfall. Based on the Mann-Kendall test, a statistically significant increase in pH was observed in SH-1, DL, SH-2, CM, and BH, along with an increase in WQI in SH-2 and SM. BH was identified as a tributary that needs priority management in the lower reaches of the Namhan River, with a "Somewhat poor" (IV) grade in T-P, "Fair" grade in WQI, and "Marginal" grade in summer.

• The Plant Pathology Journal
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• v.35 no.2
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• pp.125-136
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• 2019

Vitis vinifera is very susceptible to downy mildew (Plasmopara viticola). A number of authors have suggested different genetic populations of this fungus exist in Europe, each showing a different degree of virulence. Work performed to date indicates this diversity to be the result of different factors. In areas where gene flow is greater and recombination more frequent, the diversity of P. viticola appears to be wider. In vineyards isolated by geographic barriers, a race may become dominant and produce clonal epidemics driven by asexual reproduction. The aim of the present work was to identify the conditions that influence the genetic diversity of P. viticola populations in the vineyards of northwestern Spain, where the climatic conditions for the growth of this fungus are very good. Vineyards situated in a closed, narrow valley of the interior, in more open valleys, and on the coast were sampled and the populations of P. viticola detected were differentiated at the molecular level through the examination of microsatellite markers. The populations of P. viticola represented in primary and secondary infections were investigated in the same way. The concentration of airborne sporangia in the vegetative cycle was also examined, as was the virulence of the different P. viticola populations detected. The epidemiological characteristics of the fungus differed depending on the degree of isolation of the vineyard, the airborne spore concentration, and on whether the attack was primary or secondary. Strong isolation was associated with the appearance of dominant fungal races and, therefore, reduced populational diversity.

• Journal of Forest and Environmental Science
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• v.38 no.2
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• pp.110-121
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• 2022

Leaf functional traits widely have been used to understand the environmental controls of resource utilization strategy of plants along the environmental gradients. By using key leaf functional traits, we quantified the relationships between leaf traits and local climate throughout the distributional range of Rhododendron caucasicum Pall. in eastern and western Georgian mountains (the South Caucasus). Our results revealed, that all traits showed high levels of intraspecific variability across study locations and confirmed a strong phenotypic differentiation of leaf functional variation along the east-west longitudinal gradient in response to the local climate; out of the explored climatic variables, the moisture factors related to precipitation and number of precipitation and dry days for winter and growth seasons were more strongly related to leaf trait variation than the elevation and air temperature. Among studied leaf traits, the leaf specific area (SLA) showed the highest level of variability indicating the different resource utilization strategies of eastern and western-central Rh. caucasicum individuals. High SLA leaves for western-central Caucasian individuals work in relatively resource-rich environments (more humid in terms of precipitation amount and the number of precipitation days in winter) and could be explained by preferential allocation to photosynthesis and growth, while eastern Caucasian samples work in resource-poor environments (less humid in terms of precipitation amount and the number of precipitation days in winter) and the retention of captured resources is a higher priority appearing in a low SLA leaves. However, more evidence from a broader study of the species throughout its distribution range by including additional environmental factors and molecular markers are needed for firmer conclusions of intraspecific variability of Rh. caucasicum.

• ETRI Journal
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• v.44 no.4
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• pp.573-587
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• 2022

The agricultural sector is completely different from other sectors since it completely relies on various natural and climatic factors. Climate changes have many effects, including lack of annual rainfall and pests, heat waves, changes in sea level, and global ozone/atmospheric CO₂ fluctuation, on land and agriculture in similar ways. Climate change also affects the environment. Based on these factors, farmers chose their crops to increase productivity in their fields. Many existing agricultural ontologies are either domain-specific or have been created with minimal vocabulary and no proper evaluation framework has been implemented. A new agricultural ontology focused on subdomains is designed to assist farmers using Jaccard relative extractor (JRE) and Naïve Bayes algorithm. The JRE is used to find the similarity between two sentences and words in the agricultural documents and the relationship between two terms is identified via the Naïve Bayes algorithm. In the proposed method, the preprocessing of data is carried out through natural language processing techniques and the tags whose dimensions are reduced are subjected to rule-based formal concept analysis and mapping. The subdomain ontologies of weather, pest, and soil are built separately, and the overall agricultural ontology are built around them. The gold standard for the lexical layer is used to evaluate the proposed technique, and its performance is analyzed by comparing it with different state-of-the-art systems. Precision, recall, F-measure, Matthews correlation coefficient, receiver operating characteristic curve area, and precision-recall curve area are the performance metrics used to analyze the performance. The proposed methodology gives a precision score of 94.40% when compared with the decision tree(83.94%) and K-nearest neighbor algorithm(86.89%) for agricultural ontology construction.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.s01
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• pp.1-17
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• 1988

Rice Quality is considered to the five catagories ; the nutritional value: the characteristics of cooking. eating and processing: grain size, shape and appearance : milling yields: and storage characteristics. Because most rice is processed and consumed in whole-kernel form. the cooking and eating quality is of important and the physical properties of the intact kernel such as size, shape and general appearance are of particular significance in determining marketing quality. Eating Quality which can be directly evaluated by consumer's panel test is so complicate and variable, and thus the objective and simplified method of evaluation is required of using appropriate instruments. Even though many researches have been done to evaluate the eating quality in various aspects such as the texture of cooked rice kernels, amylogram analysis of rice powder, amylose content. gelatinization temperature. moisture absorption of rice kernel, and cooking characteristics, none of them is satisfied for the evaluation of eating quality. The improving eating quality should be also considered to many cultural factors. such as varieties, climatic and soil conditions, cultural method, handling after harvest. milling and storage conditions. In Korea, many researches in grain size. shape and appearance, and eating quality have been done with the varietal improvement mainly by rice breeders, but no effective method of evaluation was established. A few research have been done in the relationship between rice quality and cultural factors. In the future, research in rice quality should emphasize to establish the standard evaluation method in the physicochemical properties of rice kernels for application of varietal selection. and to develop cultural practices for the preserving quality characteristics of the varieties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.3
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• pp.351-357
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• 1983

To study the relationships between soybean seed yield and meteorological elements, the investigation into the important agronomic characters of Bongeui cultivar and climatic factors such as precipitation, rainy days, and temperature from 1970 to 1981 was made. The results obtained were summarized as follows: 1) Coefficients of variabilities for pod-filling rate, seed yield, number of pods per plant, and seed weight were about 38%, 30%, 30%, and 5.5%, respectively. 2) Weather conditions mainly in July and August influenced soybean production. Particularly, high temperature played an important role in soybean yield reduction. 3) Correlation coefficients between maximum, minimum, or average temperature of July (and, in the case of August, maximum temperature only) and yield or seed weight, and between those of August and podfilling rate were significantly negative. 4) Regression equations between average temperature of July or maximum temperature of August and yield were Y=-42.46X +1200.86 and Y=-37.95X + 1210.42, respectively. 5) High temperature during the flowering stage affected soybean seed yield reduction significantly.

• Korean Journal of Ecology and Environment
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• v.46 no.2
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• pp.251-264
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• 2013

This study was conducted to investigate the diversity of ectomycorrhizal fungi by surveying sites from June 2010 to October 2011. The obtained results from investigation were as follows. The total of 2 Kingdom 3 Phylum 6 classes 15 orders 34 families 59 genera and 107 species including saprophytic and ectomycorrhizal fungi was investigated. A total of 10 families 17 genera 49 species (801 ea.) of ectomycorrhizal mushroom was investigated. The mushrooms are classified into 28 families 51 genera and 99 species in Basidiomycota, 5 families 7 genera and 7 species in Ascomycota and 1 families 1 genera and 1 species in Amoebozoa. Dorminant species were Amanitaceae (14 species) followed by Russulaceae (12 species) and Boletaceae (11 species). The populaion ectomycorrhizal mushroom was highest in sites 1 and 2, and sites 4 and 5 occurrence rarely. The mushroom occurrence of ectomycorrhizal fungi was closely related to climatic conditions such as high air temperature and lots of rainfall from July to August. The environment factors which have a favorable influence of mushroom occurrence were soil pH, organic matter content of soil and air temperature of climatic environment.

• Journal of the Korean Geographical Society
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• v.48 no.2
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• pp.167-183
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• 2013

This paper aimed to investigate the Asian dust source region and climatic condition of source region by the case of Asian dust in south Korea. In order to analyze the weather condition of source region, observed the Asian dust days data and weather data in China were used. The Asian dust days originating from inner-Mongolia were the most frequent. The Asian dust days originating from all the source regions except Loess plateau were increased recently and occurred over the country. In case of Loess plateau, the frequency of the Asian dust days in 1960s was the highest and only the southern region of the south Korea was mostly affected. The relationship between the Asian dust days of Korea and climatic factors of spring and April of source region was significant. The relationship between the Asian dust days originating from the inner Mongolia and sea level pressure of April and relative humidity of spring was negative. The Asian dust days from Gobi had positive relationship with wind gust days and negative relationship with sea level pressure in April. The Asian dust days from Manchuria had negative relationship with precipitation and sea level pressure in April. The Asian dust days from Loess plateau had positive relationship with maximum wind speed and negative relationship with sea level pressure in April.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.782-785
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• 2011

Needs for MG(Microgrid) development are increasing all over the world as a solution to the problems including the depletion problem of energy resources, the growing demand for electric power and the climatic and environmental change. Especially Photovoltaic power is one of the most general renewable energy resources. However there is a problem of the uniformity of power quality because the power generated from solar light is very sensitive to climate fluctuation (variation of insolation and duration of sunshine, etc). As a solution to the above problem, ESS(Energy Storage System) is considered generally, but it has some limitations. To solve this problem this paper suggests a hybrid estimation method of photovoltaic power generation according to two climatic factors, i.e. insolation and sunshine. This result seems to help design the appropriate capacity of ESS and estimate the proper switching time between DC and AC power in the premises power system and thus maintain the uniformity of power quality.