Bypass line과 Catalyst를 공간적으로 결합한 Bypass 일체형 탈질설비를 제안하였다. 탈질설비 내부에 설치되는 Bypass의 개폐장치 의 형태에 따른 Catalyst로의 유동 변화를 확인하기 위하여 상용프로그램인 Ansys Fluent를 사용하여 탈질설비를 모델링하고 시뮬레이션을 구성하였다. 탈질설비 내의 Catalyst로 인한 계산시간과 Mesh의 수를 줄이기 위해 Porous media방식으로 Catalyst를 모델링하였다. Catalyst로 의 입구각도와 Bypass 개폐장치의 크기를 변화시키면서 시뮬레이션을 수행하고 시뮬레이션의 결과로 Catalyst로의 유동 평균속도와 균일도의 변화를 확인하였다.

Objective of this study was to investigate the residual levels of heavy metals in rice contract farming complex for exporting to China. Paddy soil, irrigation water and rice grain were taken from 20 fie1ds located in Icheon city, Cheorwon-gun, Cheongju city, Seocheon-gun, Gunsan city and Haenamgun. The elements of samples were analyzed using ion chromatography, ICP-OES, and ICP-MS after acid digestion. The arsenic (As) contents of paddy soil were ranged from 2.9 to 18.2 mg/kg, which were lower than 25 mg/kg as concern level of environmental pollution in Korea. Cadmium (Cd) was below the limit of quantitation (0.006 mg/kg) in all samples. The highest contents of copper (Cu) was detected to be 25.6 mg/kg in Seocheon-gun sample, but it was below 1/10 fold of the threshold levels 250 mg/kg for soil pollution. Also, the average contents of nikel (Ni), lead (Pb), zinc (Zn), and hexavalent chrome (Cr6+) were found to be lower than the criterion of soil pollution concern, and it was considered to be safe. The residual levels of arsenic in agricultural waters were relatively high, up to 24.3 ug/L in river water, but was detected as 1~2 ug/L level in the ground water. These levels are lower than the water quality standard, 0.05 mg/kg of agricultural water. The concentrations of mercury (Hg) and total chromium (Cr) in the white rice and brown rice were less than the limit of quantitation, and the levels of cadmium in the range of 0.004 to 0.068 mg/kg were less than safety criteria 0.2 mg/kg in Korea and China. In addition, the contents of lead (Pb) in white rice ranged from 0.002 to 0.136 mg/kg, which was safe to be 0.2 mg/kg for Korean white rice and 0.2 mg/kg for China brown rice. As a whole, the residual levels of heavy metals such as arsenic in rice was safely maintained as 1/10 to 1/20 of the residual limits of Korea and China. In conclusion, the heavy metals levels should not be worried in rice contract farming complex for exporting to China.

Materials are limited for pest control and chemical pesticides are prohibited in organic farming. Thus, the concept of pest control may not be effective for pest management in organic farm. As an alternative approach, landscape management is potentially effective and useful approach for preventing pathogen and insect pests in organic farm. It is needed to develop best practices utilizing functional biodiversity for pest management through landscape management. For this purpose, we investigated the effect of companion plants on species richness of insect pests and natural enemies in the field border area and in the crop plants (rice and soybean). In rice paddy fields, Lysimachiae foenum-graecum, Saururus chinensis were selected as effective companion plants on the paddy field levee for conserving Arachnidae as natural enemy and density suppression of insect pest such as Lissorphoptrus oryzophilus, Riptortus clavatus. As a result, damage rate of rice plant by insect pests was significantly lower (2.5%) and yield rate of healthy grains was significantly higher (8.7%) than control. In soybean fields, Marigold plants such as Tagetes patula, T. officinalis, increased Arthropod species richness and ratio of natural enemy group, and decreased ratio of insect pest group. As a result, yield (weight of 100 seeds) of healthy soybean was significantly increased (2.5%) than control. The 2nd infection rate from damage by R. clavatus was significantly lower in the treated plot than that in control. Thus, yield rates of healthy soybean in the control and the companion plant-treated plot were 79.0% and 84.3%, respectively, compared to conventional farming using chemical pesticides. Therefore, use of companion plants on field border was an effective practices for preventing pest insects and increasing yield in organic farming.

This study was conducted to investigated the distribution and ecological character of Black Soldier Fly(BSF), Hermetia illucens, to determine effects of BSF on composing ability to waste-food. The distribution of BSF was defined in all parts of the country in Korea. Its main habitat was found to be areas near cattle sheds, manure sheds, living waste dump grounds, and food waste dump grounds. Observed characteristics of BSF by developmental stage may be summarized as follows: eggs were a long oval shape of 886.9±19.7 ㎛ in major axis and 190.1±9.7 ㎛ in minor axis; they were 24.0±1.6 ㎍ in weight. One adult insect laid 1001±247 eggs in quantity; days to hatch from eggs (27℃, 60% R.H.) were 81.3±12.5 hours. Larvae which were hatched appeared to be close to white and turned into pale yellow as being last instar larva. Last instar larva ranged from 20.7±1.1 mm in size, the length of larval stage was approximately 15～20 days. Pupae exhibited red brown, 19.2±1.1 mm in size; pupal state lasted 15.5±1.4 days for female, 14.7±1.4 days for male, exhibiting the tendency of males having shorter period than females. Adult insects were sized about 13～20 mm and colored black.

The time-zone of pollinating activity according to numbers of Apis mellifera hive released in the strawberry(Maehyang var.) houses was together from 9A.M. to 4P.M., and the peak times of pollinating activity were between 11A.M and 1P.M.. The effects on pollinating activity according to numbers of A .mellifera hive released in the strawberry houses were ordered 5bee combs(11,000heads), 4bee combs(8,800heads) and 3bee combs(6,600heads). The rate of workers lost in A. mellifera hives with 5bee combs and 4bee combs during the strawberry cultivating period were lower than that of 3bee combs. The rates of fruit set by pollinating activity according to numbers of A.mellifera hive released in the strawberry houses were same level with 99%. The fruit qualities; No. of seeds, sugar content and rate of normal fruit set were same level, but fruit weight was ordered 5bee combs in 16.9g, 4bee combs in 16.4g and 3bee combs in 15.6g. The rate of marketable fruit of 4bee combs and 5bee combs were 5% to 9% higher than that of 3bee combs, respectively.

In order to improve mass rearing methods of hornfaced bee, Osmia cornifrons, in different field condition, a series of studies were conducted in apple orchard in Geochang province, eco-park in Suwon and botanical park in Yongin. 1,000 individuals and 2,000 individuals of Osmia cornifrons were released apple orchard and eco-park and botanical park respectively. Nesting rate of Osmia conifrons was most effective in case of releasing in botanical park in Yongin with 38.2% and lowest in eco-park in Suwon with 21.7%. And also number of cocoons nested in bamboo tube traps was highest in botanical park in Yongin with 3,494 individuals. Sex ratio in 3 different areas was also most effective with 58:42 in botanical park, 50:50 in apple orchard and lowest with 43:57 in eco-park. Nesting activity was shown starting point in 20th day, peak point in 38th day and ending point in 46th day after releasing of adults. This result shows nesting efficacy in botanical park designed with various species of plant sources pollinating insect, Osmia cornifrons, to increase the multiplication rate in field condition is more effective than other areas. General type of nest shows same tendency in efficacy of nesting rate compared with specific type of nest designed with dark thick cover in apple orchard. But it's result needs some further examination in same condition.

Objective of this study was to investigate the difference of cadmium (Cd) levels in rice grains from non-polluted fields and to define the gene associated with Cd uptake for producing safety food. Cd was analyzed by Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The average concentration of Cd in rice grains was 0.943 μg/kg and Cd levels ranged from 0.050 to 5.699 μg/kg. Genome-Wide Association study (GWAS) based on phenotype data for Cd levels was performed. However, results of GWAS were affected by subpopulation structure and caused false positive. Therefore, GWAS for rice ecotypes (temperate Japonica, tropical Japonica, Indica, Aus, Aromatic, and Admixture) was performed to minimize false positive. GWAS results showed that Os01g0611300, Os01g0611900, Os01g0611950, Os01g0612000, Os01g0612200, Os11g0444400, Os11g0444700, Os11g0444800, and Os11g0444900 genes have significant correlation with Cd levels in rice grains. The sequences of these genes were compared to sequence positions of each other gene (haplotype analysis). According to the results of haplotype analysis, Cd levels of non-synonymous group were higher than other groups and sequence of non-synonymous group was similar to that of Indica. These results were corresponding to the previous research result that Cd levels of Indica were higher than Japonica. Therefore, candidate genes detected through GWAS need to be examined by knock-out or cross breeding.