• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.65-65
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• 2017

밭작물 중 양파와 마늘은 높은 노동투하시간, 노임의 상승, 복잡한 수거 과정 등으로 최근 재배면적이 감소하는 추세이다. 밭농업 활성화 방안으로 생산비 절감과 작업 속도 향상을 위한 수확기계 개발 연구로 줄기절단기가 개발되었다. 이 연구는 줄기절단기 예취날의 설치각이 절단부하에 미치는 영향을 분립체 해석 기법으로 분석하고자 하였다. 실험에 사용한 시뮬레이션은 EDEM으로 인장탄성계수, 전단탄성 계수, 중첩길이, 입자 반경 및 질량, 상대속도를 이용하여 충돌시 힘을 해석하고 인장 및 전단강도, 한계, 결합 길이를 통해 입자간 결합을 설정할 수 있다. 시제품으로 설계된 줄기절단기의 치수를 활용하여 프로그램 상에서 줄기 절단 시뮬레이션을 진행하여 절단부하 결과를 얻도록 하였고 칼날 설치각을 30도, 45도, 60도로 변경하여 각각의 부하를 분석하여 경향성을 파악하고자 하였다. 실험에서 사용한 프로그램은 EDEM 2.7.1 Academic Research 버전이며 시뮬레이션을 진행한 PC의 사양은 Intel(R) $Core^{TM}$ i7-4790 CPU @ 3.60GHz, Memory 16.0GB이다. 줄기 절단 시뮬레이션에 적용시킨 줄기 모델은 마늘의 조건을 적용시켜 직경 1mm의 입자로 이루어진 지름 12mm, 높이 214mm의 원통형 모델이며 60.32N의 최대절단력을 가지고 있다. 줄기절단기는 2개의 회전날을 가지고 있으나 좌우대칭을 적용하여 절반에 대한 해석으로 하나의 회전날로 절단을 하도록 줄기 모델은 4조로 하여 3열을 140mm 간격으로 위치시켰다. 줄기절단기의 칼날은 반경 350mm로 회전하며 진행속도는 1.65m/s, 회전속도는 1680rpm으로 작업하도록 하였다. 시뮬레이션은 0.5초의 시간에 대해 해석하도록 하였으며 0.003초 간격으로 칼날에 가해지는 힘을 구하여 저장하도록 하였다. 시뮬레이션 해석시간은 약 116시간이었으며 설치각별 시간에 따른 칼날에 가해지는 압축력 값과 그래프를 얻을 수 있었다. 대부분의 시간에서 절단이 이루어지지 않으므로 0의 값을 나타내었으며 절단이 이루어지는 시점에 절단부하가 나타났다. 결과 해석을 위해 그래프의 피크 값들을 이용하였으며 그 중 상위 6개의 값으로 분석하였다. 30도, 45도, 60도의 설치각에 따른 절단부하의 평균 값은 각각 105.4N, 160.5N, 215.9N으로 나타났다. 설치각에 따른 절단부하의 경향성은 유의수준은 3.93%로 각각의 차이가 유의미하게 나타났으며 상관계수는 0.489로 증가하는 경향이 보였다. 그러나 $R^2$는 0.2394로 낮은 값을 보여 데이터 처리 방법의 개선과 적절한 회귀 모델의 적용이 필요하다. 향후 포장시험을 진행하고 복합적으로 분석하여 경향성을 자세히 분석하고자 한다.

• Journal of Applied Biological Chemistry
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• v.52 no.3
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• pp.116-120
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• 2009

We found out the new method of the consortium for the environmental friendly agriculture by 8 kinds of the selected antagonistic rhizobacteria. This research involved composition of mutual complementary consortium by each antagonistic function such as production of antibiotic, siderophore, antifungal cellulase and insoluble phosphate solubilization. The consortium No.11 among composed consortium candidates showed the most pepper growth promoting activity and Phytophthora blight suppression on the in vivo pot test of red-pepper plant. The consortium No. 11 is combination of PGPR Bacillus subtilis AH18 and Bacillus licheniformis K11. B. subtilis AH18 and B. licheniformis K11 both could produce the auxin, antifungal ${\beta}$-glucannase and siderophore. Also, they had mechanism for solubilization of insoluble phosphate. But, B. licheniformis K11 could produce the antibiotic of iturin which was able to inhibit Phytophthora capsici. We confirmed complementary noncompetitive mutualism between B. subtilis AH18 and B. licheniformis K11 of the consortium No.11. The results came out through treatment of two strains co-culture, treatment of individual culture and co-treatment of two individual cultures for the growth and Phytophthora blight suppression of red-pepper. The treatment of two strains co-culture didn't show a synergic effect in comparing sole treatment on the pepper growth promotion and Phytophthora blight suppression. But, when the pots were treated simultaneously with co-treatment of two individual cultures, an synergic effect was seen in the growth promotion of roots, stem, leaves and suppressed Phytophthora blight on red-pepper in vivo pot test.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.3
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• pp.222-226
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• 2004

This study was conducted to measure the major agronomic characteristics of 85 local varieties of perilla at Chungbuk Agricultural Research and Extension Services in 2001. Perilla accessions examined were classified into three maturity groups, i.e, early, medium, and late maturity group of 19 (23％),57 (67％), and 9 (10％) accessions, respectively. The early and late maturity groups mainly consisted of collections from middle-northern area and southern area, respectively, while the medium group consisted of accessions from all over the country. Average 1,000-seed weight (TSW) was 2.7 g. TSW of the collection from Hamyang was the greatest a 3.9 g, while the TSW of Pyungchang collection was the smallest as 1.7 g, and most of collections produced medium and small seeds. Perilla accessions with greate 1,000-seed weight seemed to be belonged to the late maturity group. Seed coat colors of perilla accessions were dark brown (30％), brown (55％) and gray brown (6％), respectively, Among seed coat colors, brown color consisted of 91％. Stem height, the number of nodes, branches, flower clusters, and capsules per flower cluster, and the length of flower cluster were positively correlated occ, while these characteristics were negatively correlated with the number of capsules per flower cluster and 1,000-seed weight. These results allowed us to select 5 perilla collections, containing 1 collection with gray white seed color, and 4 collections over 2.5g 1000 seed weight, as parental lines in the breeding program.

• Korean Journal of Medicinal Crop Science
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• v.14 no.3
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• pp.158-162
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• 2006

Achyranthes bidentata was recorded to new medicinal crop in a revised 8th edition of the Korean pharmacopoeia. Therefore, A. bidentata began to use for same purpose with Achyranthes japonica which was cultivated since old times in Korea. This study was conducted to investigate the adaptability of A. bidentata in Korea. The germination rate and speed of A. bidentata seeds were higher than those of A. japonica in $15^{\circ}C\;and\;25^{\circ}C$. The growth of A. bidentata was greater than that of A. japonica until the 60 days after transplanting, but growth after that was the opposite. There were remarkable differences between two species in growth characteristics such as flowering date, leaf fall date, plant height, stem color and no. of branches. The flowering and leaf fall date of A. bidentata were earlier than A. japonica by July 7 and September 26. The plant height and number of branches of A.japonica were longer and more than A. bidentata, but the cluster length and no. of flowers per cluster of that were shorter and fewer than this. Number of supporting roots of A. bidentata and A. japonica was 10.7 and 14.6 per plant, respectively. The average yield was not different between two species. The yield of A. bidentata was 166 kg/l0 a in Suwon and 309 kg/10 a in Naju of Korea. The suitable cultivation region of A. bidentata was judged to southern area of Korea.

• Journal of The Korean Association For Science Education
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• v.33 no.1
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• pp.79-93
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• 2013

This study examined value-judgement and decision-making process of middle school students on three biotechnology related socioscientific issues (SSI) (i.e. designer baby, amniotic fluid test, and embryonic stem cell research). In particular, it focused on the level of consistency in their value application to the decisions. Twenty 8th grade students participated in the SSI program. The participants were asked to mark their positions on each issue before and after the debates. All classroom and sub-group debates were audio-recorded. The researcher conducted individual interviews with 10 students after the program. The results show three patterns emerging. First, five students applied their personal values in a consistent manner when making decisions on the three consecutive issues. Second, three students demonstrated incremental resoluteness in their value application as the sessions proceeded and had tendency to be oriented towards a specific value, more so towards the end of the program than the beginning. And third, four students gradually showed ambivalence in their decisions as they participate in the program. The results suggest that science teachers addressing SSI need to encourage students to be aware of their own values and to engage in internalized decision-making in light of those values. They also need to be aware of the possible challenges that students might feel in their decision-making process caused by the complexity of SSI.

• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.103-107
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• 2016

This study aims to select the most appropriate poplar clones for planting on short rotation coppice poplar plantations in a riparian area. The research investigated biomass production, nitrogen and carbon absorption with 2-year-old poplar (Populus spp.) clones including P. euramericana clone Eco28, P. deltoides hybrid clone 97-18, and P. alba ${\times}$ P. glandulosa hybrid clone 72-30. The average number of stems per stump was five and P. euramericana clone Eco28 had the greatest average number of live stems per stump with 5.9. The average stem diameter was 23.2 mm, and P. deltoides hybrid clone 97-18 achieved the largest average diameter with 25.4 mm. The average annual above-ground biomass production of Populus deltoides hybrid clone 97-18 was 16.1 ton/ha/year, followed by P. alba ${\times}$ P. glandulosa hybrid clone 72-30 and P. euramericana clone Eco28, 12.3 and 5.4 ton/ha/year, respectively. The average annual nitrogen uptake of poplar clones was 46.5 kg/ha/year. P. alba ${\times}$ P. glandulosa hybrid clone 72-30 had the highest average, 63.1 kg/ha/year. The average of annual carbon absorption was estimated 5.3 ton/ha/year and Populus deltoides hybrid clone 97-18 showed the best results with 7.7 ton/ha/year. Based on the results given above, P. deltoides hybrid aspen clone 97-18 is considered as the most suitable poplar clones for wood biomass production on riparian areas.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.397-400
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• 2012

Perilla is an excellent oil crop for linolenic acid production but still needs more research to improve grain yield and chemical properties. We tried to estimate the possibility for improving grain yield and its quality by applying nitrogen top dressing(4kg per 10a) at 5 days after flowering stage of perilla, using a cultivar Yujin. This study investigated the growth characteristics and seed quality. Nitrogen top dressing on the flowering stage has little affected on such traits as length, node number and diameter of main stem, and branch, cluster and capsules numbers per plant. But compared with standard cultivation as a control, top dressing showed more leaf chlorophyll content by 85%, higher 1000-grain-weight by 31%, and one day extension of maturing period; consequently, grain outyielded by 60% with 123kg per 10a. Seed chemical components also showed 33.3% protein and 48% oil contents that were 11.5% and 6.2% higher than those of control, respectively. Also by top dressing, saturated fatty acid (palmitic and stearic acid) decreased and linoleic acid among unsaturated fatty acids increased. It is concluded that nitrogen topdressing at late flowering stage promotes grain yield and quality of perilla.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.4
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• pp.240-246
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• 2014

The present study was conducted to evaluate the productivity of $Sorghum{\times}sudangrass$ (SX17) hybrid and BMR (brown mid rib) $Sorghum{\times}sudangrass$ hybrid and silage quality of these forages with corn grain supplementation. The effect of corn grain supplementation on the quality of silages was also investigated. No remarkable differences at growth characteristics and productivities in two hybrids were found. Sugar content, however, in stem of BMR hybrid showed significantly great (p<0.05) and the difference between two hybrids was about $2B^{\circ}$. Ratio of lactic acid in total organic acid in BMR hybrid (82.8%) was significantly greater than the control (SX17 hybrid) (78.5%) (p<0.05). Ratio of butyric acid in total organic acid in SX17 hybrid (18.5%) was significantly greater than BMR hybrid (9.8%) (p<0.05). According to the result of organic acid ratio, it could be assumed that the use of BMR hybrid can improve silage quality. NDF and ADF contents in both SX17 and BMR hybrids were significantly declined with increased corn grain supplementation (p<0.05). Different TDN values in SX17 (56.2) and BMR (57.1) hybrids were detected. However, TDN values of both SX17 and BMR hybrid silages were significantly elevated by increasing the proportion of ground corn (p<0.05).

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.3
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• pp.156-160
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• 2020

This study was conducted at the National Institute of Animal Science from 2010 to 2017. As a variety that is sufficiently productive in the southern regions to replace imported varieties and sufficiently cold-resistant to be cultivated in the central-northern regions, "IR605" was developed and submitted to the Korea Seed & Variety Service in an application for protection. The novel Italian ryegrass variety "IR605" is a diploid with green leaves, a semi-erect growth habit before wintering, and an erect growth habit in the spring. "IR605" was a medium maturing variety with a heading date of around May 15th. "IR605" had a flag leaf width of 9.9 mm, flag leaf length of 26.7 cm, and plant length on the heading date of 100 cm, which was approximately 5 cm longer than "Kowinearly." The stem thickness and ear length of "IR605" are 0.08 mm thicker and 0.5 cm longer than those of "Kowinearly", respectively. The cold-resistance of "IR605" was weaker than that of "Kowinearly", but strong enough to be cultivated in Pyeongchang, Gangwon province. The dry matter yield of "IR605" (9,308 kg/hectare) was 20% higher than that of "Kowinearly", which was further pronounced in the southern region of Haenam, where there was a 52% increased (p < 0.05). The in vitro dry matter digestibility of "IR605" was 68.4% at which was slightly higher than that of "Kowinearly", The total digestible nutrients was 58.5%, which was slightly lower than "Kowinearly". Overall, the feed quality characteristics of "IR605" were similar to those of "Kowinearly".

• Research in Plant Disease
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• v.10 no.4
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• pp.324-330
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• 2004

This studies were investigated the occurrence of sclerotinia rot at the crisphead lettuce field in Uiryeong-Gun, Gyeongsangnam-Do from January to May in 2003. Average incidence rates of sclerotinia rot on crisphead lettuce was up to 21.9% at the five plastic houses. A total of 140 isolates of Sclerotinia sp. were obtained from diseased leaves of crisphead lettuce. Among them, the fungi YR-1 was isolated, which showed highly virulent on the whole plant. the YR-1 was identified as Sclerotinia sclerotiorum based on the formation, color, shape and size of sclerotium and apothecium. For the pathogenicity test, the most suitable inoculum quantity of YR-1 strain was selected as the triturated mycelial suspension of $A_{550}$=0.8, 40 ml showing disease incidence of 94%, and the symptom showed as same as at the fields, the leaves and stem had rotten and developed white downy mycelial at the diseased lesion on the leaves and stems, and produced black and irregular sclerotinia. This is the first report on the pathogenicity test using by triturated mycelial suspension-inoculum of the pathogen for the sclerotinia rot of crisphead lettuce.