• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.6
• /
• pp.991-997
• /
• 2011

Soil erosion and sediment has been known as one of pollutants causing water quality degradation in water bodies. With global warming issues worldwide, various soil erosion studies have been performed. Although on-site monitoring of sediment loss would be an ideal method to evaluate soil erosion condition, modeling approaches have been utilized to estimate soil erosion and to evaluate various best management practices on soil erosion reduction. Although the USLE has been used in soil erosion estimation for the last 40 years, the USLE model has limitations in estimating event-based soil erosion reflecting rainfall intensity and rainfall duration for long-term period. Thus, the calibrated model, capable of simulating soil erosion using hourly rainfall data, was utilized in this study to evaluate the effects of rainfall amount and rainfall intensity on soil erosion. It was found that USLE soil erosion value is $3.06ton\;ha^{-1}\;yr^{-1}$, while soil erosion values from 2006~2010 were $2.469ton\;ha^{-1}\;yr^{-1}$, $0.882ton\;ha^{-1}\;yr^{-1}$, $1.489ton\;ha^{-1}\;yr^{-1}$, $2.158ton\;ha^{-1}\;yr^{-1}$, $1.602ton\;ha^{-1}\;yr^{-1}$, respectively. Especially, soil erosion from single storm event for 2008-2010 would be responsible for 30% or more of annual soil loss. As shown in this study, hourly soil erosion estimation system would provide more detailed output from the study area. In addition, the effects of rainfall intensity on soil erosion could be evaluated with this system.

• The Journal of Society for e-Business Studies
• /
• v.26 no.3
• /
• pp.97-117
• /
• 2021

Predicting term deposit subscriptions is one of representative financial marketing in banks, and banks can build a prediction model using various customer information. In order to improve the classification accuracy for term deposit subscriptions, many studies have been conducted based on machine learning techniques. However, even if these models can achieve satisfactory performance, utilizing them is not an easy task in the industry when their decision-making process is not adequately explained. To address this issue, this paper proposes an explainable scheme for term deposit subscription forecasting. For this, we first construct several classification models using decision tree-based ensemble learning methods, which yield excellent performance in tabular data, such as random forest, gradient boosting machine (GBM), extreme gradient boosting (XGB), and light gradient boosting machine (LightGBM). We then analyze their classification performance in depth through 10-fold cross-validation. After that, we provide the rationale for interpreting the influence of customer information and the decision-making process by applying Shapley additive explanation (SHAP), an explainable artificial intelligence technique, to the best classification model. To verify the practicality and validity of our scheme, experiments were conducted with the bank marketing dataset provided by Kaggle; we applied the SHAP to the GBM and LightGBM models, respectively, according to different dataset configurations and then performed their analysis and visualization for explainable term deposit subscriptions.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.41 no.3
• /
• pp.168-175
• /
• 2021

The optimal determination of seeding rate is critical to minimizing uncertainties about the large variations observed in forage quality and productivity when alfalfa is cultivated under different geographical areas and growing conditions. The objective of this investigation was to provide information about the proper seeding rate according to harvest timing for alfalfa cultivation in the Northern regions of Korea. Alfalfa was sown in September 2018 at a seeding rate of 20, 30 or 40 kg/ha and harvested four times in 2019: May 3, July 2, September 11, and October 13. Regardless of seeding rate, alfalfa plant height was longest at the third harvest (113 cm) and the shortest in the last annual harvest (43.8 cm). However, seeding rate had no effect on alfalfa plant height at any harvest. Forage relative feed value was increased in the first cutting but decreased in the third cuttings as seeding rate increased. However, seeding rate had slight effect on alfalfa forage quality components at the second and fourth cuttings. Total annual DM and crude protein production (in 4 harvests) was greater at higher seeding rates. Plots seeded at a rate of 40 kg/ha produced on average 1,257 and 2,620 kg/ha more forage (DM basis) than those seeded at a rate of 30 or 20 kg/ha, respectively. Forage DM production at the first, second, third, and fourth harvests accounted for 36.1, 24.0, 27.1, and 12.8 % of total annual DM production, respectively. Overall, small differences were seen when alfalfa seeding rate was different but maximum forage DM production (in four harvests) was detected when seeding rate was 40 kg/ha. These data could be useful to the alfalfa growers by allowing them to make more accurate trade-offs between seed price and the expected magnitude of forage yield gains in order to select the best seeding rate.

• The Journal of the Korea Contents Association
• /
• v.21 no.9
• /
• pp.299-311
• /
• 2021

The purpose of this study is to analyze the ripple effect of the Chinese education industry on the national economy by using the industry-related table of 2017 by the China Statistical Office to use it as policy data for revitalization of the Chinese education industry in the future. To achieve this purpose, 149 industries in the basic classification of the industry-related table were classified into 32 industries. Based on these classifications, by analyzing the production induction coefficient, sensitivity coefficient, influence coefficient, yield inducement coefficient, production tax induction coefficient, and labor induction coefficient, etc. The purpose of this study is to understand the relationship between different industries and to find out the economic impact of the Chinese education industry. The analysis results show that in 2017, the total production induction coefficient of China's education industry was 1.7188, the row total was 1.0626, the sensitivity coefficient was 0.01211, the influence coefficient was 0.01958, the income induction coefficient was 0.6667, the production tax induction coefficient was 0.035, and the final demand was 1 billion yuan. When this occurs, the labor induction coefficient shows a total of 31,254 persons (indirect 15,541 persons, direct 15,713 persons). Based on the analysis results, this study suggested the implications that government support, technology introduction and application of new operating models, policy regulations, and efficient supervision of the system and president are required for further development of the Chinese education industry.

• The Korea Journal of Herbology
• /
• v.36 no.5
• /
• pp.109-115
• /
• 2021

Objectives : 'Johyun' yulmoo which is a new variety of Coix lacryma-jobi var. ma-yuen Stapf sprout was developed and registered by Rural development administration in 2004. This variety was derived from the cross between single cross of Suwon-6 and Okayama and UCN300-25 as F1. It is characterized by early maturity, short plant height, a strong resistance, and a superior yield and is suitable for the central and northern regions. Accordingly, we were performed and evaluated single oral dose toxicity test of 'Johyun' yulmoo sprout (JYS) in Sprague-Dawley (SD) rats. Methods : Single oral dose toxicity test was performed using with male and female rats. Rats were divided into two groups: Group 1, vehicle-treated rats (Control); Group 2, JYS 5000 mg/kg-treated rats. JYS was orally administered to male and female rats at dose levels of 5000 mg/kg. Animals were monitored on the mortality, clinical signs, body weight changes, and necropsy findings for 14 days. groups : Group 1, vehicle-treated rats (Control); Group 2, JYS 5000 mg/kg-treated rats. JYS was orally administered to male and female rats at dose levels of 5000 mg/kg. Animals were monitored on the mortality, clinical signs, body weight changes, and necropsy findings for 14 days. Results : After oral treatment of JYS, we could not find any mortality at 5000 mg/kg. Compared with the control group, there were also no significant differences in clinical sign, weight changes, weight gain, and gross abnormalities in JYS 5000 mg/kg-treated group. Conclusions : Taken together, these results suggest that approximate lethal dose of JYS was considered as over 5000 mg/kg. Results from this study provide scientific evidence for the safety of JYS. Moreover, this study could be used as a basis for dose-setting data of the repeated dose 13-week oral toxicity test of JYS.

• Korean Journal of Breeding Science
• /
• v.42 no.1
• /
• pp.56-60
• /
• 2010

This study was carried out to develop of macro-protocol and the biosafety guide Golden Rice, modified vitamin A at large scale GMO field. Commercialization of genetically modified (GM) plants will be required the assessment of risks associated with the release of GM plants that should include a detailed risk assessment of their impacts in the environment and human health. Prior to GM plant release, applicants should provide the information on GM crops for approval. A total of $4,700m^2$ GM field, each of Golden Rice and 'Nakdong' were used for further analysis on agronomic traits and pathogenesis. Generally plant growth and panicle number in the transgenic lines were lower than in the wild type under field condition. The major agronomic traits such as plant growth, grain quality in Golden Rice were similar than in 'Nakdong'. The yield difference was due to reduced ripened rate and the 1,000 grain weight. The grain shape was similar donor plant, however, color of brown rice was different from segregation. Also the difference of pathogenesis reaction was not significant in the leaf blast and sheath blight between Golden Rice and 'Nakdong'. These results provided the agronomic data and pathogenesis for risk assessment analysis of Golden Rice and suggested that the macro-protocol could be useful to detect GM plants.

• Applied Chemistry for Engineering
• /
• v.29 no.6
• /
• pp.652-656
• /
• 2018

In this study, effects of the reaction pressure were studied for petroleum-based pitch synthesis. A two-stage reaction process was performed based on different reaction pressure conditions. Each stage experiments for the two-stage reaction were consecutively carried out. The first stage was consisted of three different pressure conditions; high (10 bar), normal and low (0.1 bar). And the second stage was carried out at the normal and low (0.1 bar) pressure. The pitch synthesis was realized at $400^{\circ}C$ for 2 h. Thermal properties and molecular weight distributions of each samples were investigated by analyzing the softening point and MALDI-TOF data. Volatilized components during the pith synthesis were measured by GC-SIMDIS. In case of the first-step reaction with the high pressure condition, the low molecular weight component participated to the pitch formation more effectively and the pitch with the low softening point was obtained. However, for the case of the first-step with the low pressure, the low molecular weight component was vent outside and the partial coke formation occurred. Eventually, pitch properties such as the softening point and yield were controlled effectively by changing the pressure in the pitch synthesis reaction.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.12 no.3
• /
• pp.290-298
• /
• 2019

The proportion of farm households in the total population is decreasing every year. The aging of rural areas is expected to deepen. The aging of agriculture is continuing due to the aging of the aged population and the decline of the young population, and agricultural manpower shortage is emerging as a threat to agriculture and rural areas. The existing facility cultivation was concentrated on the production / yield per unit area. However, nowadays, not only production but also crop quality should be good so that the quality of crops must be improved because they can secure competitiveness in the market. Therefore, the government plans to increase the productivity by hi-techization of ICT infrastructure horticulture and to plan the dissemination of energy saving smart greenhouse. Therefore, it is necessary to develop a Smart Farm convergence service system based on a hybrid algorithm to enhance diversity and connectivity. Therefore, this study aims to develop smart farm convergence service system which collects data of growth environment of the rhizosphere environment of crops by wireless and monitor smartphone.

• Korean Journal of Materials Research
• /
• v.28 no.11
• /
• pp.663-670
• /
• 2018

H13 tool steels are widely used as metallic mold materials due to their high hardness and thermal stability. Recently, many studies are undertaken to satisfy the demands for manufacturing the complex shape of the mold using a 3D printing technique. It is reported that the mechanical properties of 3D printed materials are lower than those of commercial forged alloys owing to micropores. In this study, we investigate the effect of microstructures and defects on mechanical properties in the 3D printed H13 tool steels. H13 tool steel is fabricated using a selective laser melting(SLM) process with a scan speed of 200 mm/s and a layer thickness of $25{\mu}m$. Microstructures are observed and porosities are measured by optical and scanning electron microscopy in the X-, Y-, and Z-directions with various the build heights. Tiny keyhole type pores are observed with a porosity of 0.4 %, which shows the lowest porosity in the center region. The measured Vickers hardness is around 550 HV and the yield and tensile strength are 1400 and 1700 MPa, respectively. The tensile properties are predicted using two empirical equations through the measured values of the Vickers hardness. The prediction of tensile strength has high accuracy with the experimental data of the 3D printed H13 tool steel. The effects of porosities and unmelted powders on mechanical properties are also elucidated by the metallic fractography analysis to understand tensile and fracture behavior.

• Journal of Life Science
• /
• v.31 no.2
• /
• pp.175-182
• /
• 2021

Saccharomyces lysate has the well-known function of soothing the skin in various ways: it is an anti-irritant and can treat skin care conditions, such as skin whitening and antioxidative activity. However, data on the safety for use of Saccharomyces lysate in cosmetics and skin care products are still limited. To design a new cosmetic material with antioxidant and skin-whitening effects, 80 yeast strains were isolated from berries grown in Sunchang. Among the isolates, the FT4-4 strain, which exhibited superior biological activities, was selected for further experiments. The FT4-4 strain was identified as Saccharomyces cerevisiae by 18S rRNA gene sequencing analysis. S. cerevisiae FT4-4 showed higher DPPH radical-scavenging (51.41%), superoxide dismutase (62.23%), and tyrosinase inhibition (64.75%) activities. The highest yield of biomass (3.16 g/l) and maximum growth rate of S. cerevisiae FT4-4 were observed within 16 h. Furthermore, the cytotoxicity potential of S. cerevisiae FT4-4 on B16F10 melanoma cells was measured by an MTT assay, and the results indicated that S. cerevisiae FT4-4 had a capacity to inhibit melanin up to 72.02% at an initial 10 mg/ml concentration. These results suggest that S. cerevisiae FT4-4 could be a promising candidate as a multi-functional material for application in the cosmetic industry, especially because of its antioxidant and skin-whitening effects.