• Journal of Korean Society on Water Environment
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• v.21 no.6
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• pp.617-623
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• 2005

Forestry and agricultural land uses constitute 85% of Korea and these land uses are typically mixed in many watersheds. Biological Oxygen Demand (BOD) concentration is a primary factor for managing water qualities of the water resources in Korea. BOD loadings from diffuse sources, however, not well monitored yet. This study aims to assess BOD loadings from diffuse sources and their affecting factors to conserve quality of water resources. Event Mean Concentration (EMC) of BOD was calculated based on the monitoring data of forty rainfall events at four agricultural-forestry watersheds. Exceedence cumulative probability of BOD EMCs were plotted to show agricultural activities in a watershed impacts on the magnitude of EMCs. Prediction equation for each rainfall event was proposed to estimate BOD EMCs: $EMC_{BOD}(mg/L)=EXP(0.413+0.0000001157{\times}$(discharged runoff volume in $m^3$)+0.018${\times}$(ratio of agricultural land use to total watershed area).

• Magazine of the Korean Society of Agricultural Engineers
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• v.32 no.E
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• pp.59-66
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• 1990

Abstract The formulation of the probabilistic finite element method was briefly reviewed. The method was implemented into a computer program for frame analysis which has the same analogy as finite element analysis. Another program for Monte Carlo simulation of finite element analysis was written. Two sample structures were assumed and analized. The characteristics of the second moment statistics obtained by the probabilistic finite element method was examined through numerical studies. The applicability and limitation of the method were also evaluated in comparison with the data generated by Monte Carlo simulation.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2001.06a
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• pp.163-166
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• 2001

One of the most important factors influencing the outbreak and severity of foliar diseases is the duration of wetness from dew deposition, rainfall, or irrigation. Models may provide good alternatives for assessing leaf wetness duration (LWD) without the labor, cost, and inconvenience of making measurements with sensors.(omitted)

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2001.06a
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• pp.93-96
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• 2001

Estimation of leaf wetness duration (LWD) facilitates assessment of the likelihood of outbreaks of many crop diseases. Models that estimate LWD may be more convenient and grower-friendly than measuring it with wetness sensors. Empirical models utilizing statistical procedures such as CART (Classification and Regression Tree; Gleason et al., 1994) have estimated LWD with accuracy comparable to that of electronic sensors.(omitted)

• Bulletin of the Korean Mathematical Society
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• v.56 no.6
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• pp.1511-1524
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• 2019

In this paper, we investigate the uniqueness of meromorphic functions of finite order concerning sharing small functions and prove that if f(z) and ${\Delta}_cf(z)$ share a(z), b(z), ${\infty}$ CM, where a(z), b(z)(${\neq}{\infty}$) are two distinct small functions of f(z), then $f(z){\equiv}{\Delta}_cf(z)$. The result improves the results due to Li et al. ([9]), Cui et al. ([1]) and $L{\ddot{u}}$ et al. ([12]).

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2019.08a
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• pp.238-238
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• 2019

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.4
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• pp.235-239
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• 2005

An accurate fire danger rating model can contribute to effective forest fire prevention activities. This study evaluates the national forest fire danger rating index based on forest fire statistics data from 1999 to 2002. The number of fires was related to the forest fire danger rating index $(R^2=0.67)$, and no correlation was found with burned areas. A one-way ANOVA test between forest fire danger rating levels and forest fire statistics data indicated that a difference in the number of fires was found among 'danger', 'precaution' and 'none' levels, but 'precaution' and 'none' levels could not be delineated. In the case of a burned area, no difference was found among the three levels.

• Journal of Agricultural Extension & Community Development
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• v.22 no.2
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• pp.175-190
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• 2015

Most studies examining the sub-categories of agro-industry used to access an inter-industry analysis. However, These are some limitations that researchers set sub-categories differently according to their needs. Thus, This study aims to empirically explore the agro-industry sub-categories by area of academic research on agricultural science. The National Standard Science and Technology Classification(NSSTC) codes were used to classify academic research on agricultural science. This codes were examined the sub-categories using Korean input-output statistics industry and product classification by hiring 220 departments of 37 agricultural colleges. Results showed that studies using an inter-industry analysis coincided in terms of agricultural production, but showed differences in forward and backward linkage industries and services. Forward linkages industry were clearly limited to industries in which agricultural products are inputted as raw materials. Then, in terms of services related to agriculture, Previous studies represent fields such as transport and real estate, which are not included. Moreover, Research institutions overlooked by previous studies occupy an important position.

• Journal of Korean Society of Rural Planning
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• v.20 no.4
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• pp.193-208
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• 2014

This study aims to identify feasible policy direction of the 6th industrialization in agriculture based on the current agricultural and rural environment in Korea. To do so, this study employes a heckman selection model to correct a probable selection bias, utilizing the Korean agricultural census in 2010 and the agricultural statistics of farm enterprises in 2011. This study focuses on the differences of the farm and off-farm income determinants, according to conjoint types of the 6th industrialization such as Type 1 (primary+secondary+tertiary) vs. Type 2 (primary+secondary or primary+tertiary). The empirical results show Type 2 has much higher possibilities to earn farm and off-farm income in Korea, especially for farm enterprises. This study concludes with providing some policy implications reflecting rural and agricultural environment in Korea.

• The Korean Journal of Applied Statistics
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• v.10 no.1
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• pp.15-27
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• 1997

Randomized block design (RBD) with three replication is very frequently adopted in agricultural experiments of the Rural Development Administration of Korea. Even though it works well in field trials of traditional crops, it may not accomodate trial site conditions and/or experimental environment. In this research report, we deal with two such cases. The first case is for a crop experiment in green houses. In house conditions, RBD may not be appropriate since it cannot reflect two directions of the yield gradient. So, a Latin square design is suggested as an alternative. The second case is for local field experiments of the newly-inbred rice. RBD with three replications is used without doubt for decades, even though the site layout is not appropriately shaped for the design. In this case, we suggest the RBD in two blocks with multiple replicates for control varieties as an alternative. To improve the quality of statistical experimental designs in over one-thousand agricultural trials performed annually in the Rural Development Administration, we need to re-train agricultural researchers on the design and analysis of experiments and call for concerns of Korean statisticians.