• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.3
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• pp.217-225
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• 2017

This research represents comparison and validation of static aerodynamic results in different wind tunnel organizations and EFD-CFD results. KAFA conducted wind tunnel tests with Standard Dynamics Model(SDM) which is based on the NRC model, the same configuration of KARI; and then compared and analyzed similarities and differences of the data from KARI and NRC results for verifying the accuracy of wind tunnel tests. Also, We compared the result of CFD with that of wind tunnel tests and examined strakes effect in static characteristics which are attached on the forward fuselage of SDM for investigating the cause of some discrepancies. From this analysis, there are some discrepancies in Cm tendency between EFD-CFD and it did not show the big difference of aerodynamic characteristics by strake effects. Thus, we need to research additionally for analyzing the different cause of some discrepancies such as vortex structures by the rear strut or intake of SDM and regenerating grid resolution of CFD.

• Journal of Bio-Environment Control
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• v.12 no.2
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• pp.72-76
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• 2003

This study was conducted to estimate stimulation of plant growth of green and red leafy lettuces (Lactuca sutiva L. cv. Chungchima and Jugchima) at affected by covering method and time with protected film materials containing concentrated PO film and GA$_3$ foliar spray. Plants were covered with ‘Pasraido’ material from October 26 to November 31 (direct 1), from November 5 to November 31 (direct 2), or with a tunnel, or direct 2＋ tunnel. Mean air temperature and relative humidity under the covering were higher in direct and tunnel, direct and non-covering, in that order. The fresh weight and dry weight of red and green lettuces increased in direct and tunnel followed by direct 1, direct 2, tunnel and the control. GA$_3$ treatment promoted the growth in all covering methods, but decreased the chlorophyll contents. Fresh weight and dry weight were higher in red lettuce than in green lettuce in the control.

• The Journal of the Korea Contents Association
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• v.11 no.9
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• pp.443-452
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• 2011

This research aims at investigating the factors that affects the wearing of the nuclear protection equipment by radiology students. We measured the factors related to the wearing of the nuclear protection equipment based on the theory of planned behavior (TPB). We collected 192 survey records from 230 radiology students in Kwang-ju and Chun-nam providence who finished the clinical training. Based on Logistic Regression analysis, we found that the wearing of the nuclear protection equipment is statistically more probable as the level of study is lower, the scale of practicing hospital is smaller, the attitude rating is lower, and the rating of perceived behavioral control is higher. We argue that the development of educational program considering factors like the perceived behavioral control is required to enhance the degree of wearing the nuclear protection equipment in the clinical training of college students.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.432-437
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• 2017

Yellow sticky traps have been commonly used for monitoring tobacco whitefly populations in open-fields, as well as in greenhouses. However, the attractiveness depends on various factors such as the reflected intensity (brightness) and hues of yellow color (wavelength) of the trap surface, which is often influenced by environmental conditions and may sometimes affect tobacco whitefly capture. Therefore, the use of light-emitting traps can be a significant complementary tool to strengthen the attractiveness and selectivity of these traps. This research was carried out in tomato greenhouses to evaluate the light-emitting trap as potential attractants for Bemisia tabaci adults. The results showed that B. tabaci adults on average preferred (p>0.05) traps in yellow lights (590 nm) ($168{\pm}7.6adults/trap$) compared to traps in white lights ($106{\pm}4.6adults/trap$) and traps without lights ($60{\pm}4.8adults/trap$). The yellow light trap(590 nm) showed the most attractive to B. tabaci adults, followed by a little lower attraction to the white light trap(450-625 nm), whereas the control (no light trap) was little attractive to B. tabaci adults. These results suggested that yellow and white light traps could have a promising use in greenhouses for the identification, monitoring, and pest control tools of tobacco whiteflies.

• Journal of Plant Biotechnology
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• v.34 no.1
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• pp.11-17
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• 2007

Previously developed transgenic watermelon rootstocks (gongdae) inserted by CGMMV-CP were examined to test the virus tolerance levels. In the restricted plastic house, the $T_{3}$ watermelon rootstock showed tolerance to CGMMV until 70 days after inoculation on the leaves while the non-transformed watermelon rootstock became susceptible at 20 days after inoculation. In the field, tolerance efficiency of transgenic rootstocks maintained up to 40% at 71 days after contamination with CGMMV in the soil while all of the non-transformed rootstocks became susceptible at 37 days with the same condition. In the same field, transgenic rootstocks showed more tolerance to CGMMV than the non-transformed rootstocks as those were inoculated on the leaves, but it showed only 10 days delay before being susceptible. Therefore, transgenic rootstocks have a characteristic of delay effect against CGMMV susceptibility, rather than resistance character. From $T_{3}$ rootstocks homozygous for the CGMMV-CP horticulturally favorable individuals were selected for further breeding and a transgenic line was finally obtained at the $BC_{1}T_{5}$. A material transfer experiment was conducted to find out if the DNA, RNA or expressed protein in the transgenic rootstocks could move to the grafted scion (non-transformed watermelon, Super-Kumcheon). PCR, northern, and western blot analysis were performed and no evidence of transferring of those materials from rootstock to scion was ever found.

• Research in Plant Disease
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• v.14 no.2
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• pp.107-111
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• 2008

For the eco-friendly control of fruit rot of fig, disease incidences according to the cultural practices at 51 fig orchards in south coast area of Korea were surveyed in 2002, and the effect of soil mulch and potassium phosphonate on fruit rot of fig was evaluated from 2002 to 2004. Diseased fruits of fig orchards of open field, rain shading, and vinyl house were 33.3%, 7.5%, and 0%, respectively. Diseased fruits were rated at 34.6%, 35.7%, and 27% as the tree spacing of $2m{\times}2m,\;2m{\times}3m,\;and\;3m{\times}4m$, respectively. Among the soil mulching materials, barley straw showed disease incidence of 1.8% and 3.5% of diseased fruits compared to 42.1% and 48% of no mulching in 2002 and 2003, respectively. Diseased fruits in dark paper film mulching were recorded at 4.8% and 12% in 2002 and 2003, respectively, which were lower than those in dark polyethylene film mulching at 11.2% and 26.2%. When potassium phosphonate(1,000 ppm) was sprayed 3 times with 10 days intervals from the beginning of disease occurrence, disease incidences were rated at 3.0% and 2.0% in 2003 and 2004, respectively, which were much lower than those of control at 45.9 % and 39.3%.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2002.12a
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• pp.58-73
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• 2002

지방산을 이용한 살충비누의 제조와 이를 이용한 해충의 환경친화적 방제연구를 수행하였고 그 내용을 요약하면 다음과 같다. 1. 각 지방산의 중화가(Acid value)를 기준으로 비누화에 필요한 수산화칼륨의 투입량을 결정할 수 있었으며, 야자지방산의 경우 중화가가 266.3mg KOH/g으로 지방산 1kg당 수산화칼륨 266g이 필요한 것으로 나타났다. 2. 25%의 비누 함량이 되게 제조하기 위해서 지방산별 반응식을 조사하였고, 이에 따라 물의 첨가량을 결정할 수 있었으며, 야자지방산을 이용한 25% 살충비누의 제조에는 지방산 1kg에 수산화칼륨 266g과 물 3.459 ${\ell}$ 가 소요되고 제조된 비누액은 4.644 ${\ell}$인 것으로 나타났다. 또한 사용하는 물은 연수를 이용하여야 하였다. 3. 25% 제조된 살충비누의 물성을 조사한 결과 젤리상의 올레인산 비누를 제외하고는 점도가 낮은 액상이었으며, 산도는 알카리성으로 25% 야자지방산의 경우 pH 9이상으로 나타났다. 또한 50% 이상 고농도의 살충비누를 제조하면 냉각 후 젤리상태가 되어 희석하여 이용하는데 불편하였다. 4. 살충비누 제조공정의 요인으로 반응온도는 중탕방식으로 90$^{\circ}C$이상, 교반속도는 60 ${\sim}$ 120 rpm. 반응시간은 30분 이상이 양호한 것으로 나타났다. 5. 살충비누제조 공정은 중탕, 교반 가능한 반응기를 활용하여 (1) 수산화칼륨 수용액 제조 및 가온(90$^{\circ}C$) (2) 지방산 투입 (3) 30분이상 교반 반응 (4) 냉각을 통해 제조할 수 있었다. 6. 고추진딧물의 포장 방제가 조사시험결과 모든 지방산에서 살충효과를 나타냈으며, 지방산의 탄소수가 낮을수록, 살포 농도가 높을수록, 살포회수가 증가할수록 방제가가 높은 경향이었다. 7. 25% 야자지방산의 경우 50배에서 5일간격 2회처리 후부터 고추에 발생하는 진딧물에 대한 방제가가 92%이상이 되었으며, 100배액에서는 5일간격 3회처리 후부터 94%의 방제가를 나타내었다. 8. 양배추의 복숭아진딧물에 대한 25% 야자지방산 살충비누 50배액의 살포결과 1회 처리후 95%이상, 2회 처리후 100%에 가까운 방제가를 나타냈다. 9. 강낭콩의 점박이응애에 대한 25% 야자지방산 살충비누 50배액, 100배액 살포결과 2회처리 후부터 거의 100%에 가까운 방제효과를 보였으며, 알에 대한 부화억제효과도 인정되었다. 10. 효과증진제 첨가 실험결과 이소프로필알콜 0.1%이상 첨가 살포에서 2회처리시에 약간의 살충력 증진 효과를 보였으며, 규조토 첨가는 효과가 없는 것으로 나타났다. 11. 노지재배 고추의 약해검정결과 25%카프릴산비누 50배액을 제외하고는 약해가 발생하지 않았으며, 25% 카프론산 비누의 100배액은 고추 유묘기에 약해를 나타내었다. 양배추에서는 25% 카프릴산 비누 100배액에서 약해를 보였으나, 25% 야자지방산의 경우 50 ${\sim}$ 100배액 어디에서도 액해를 보이지 않았다. 별도로 적용한 시험에서, 토마토의 경우에도 25% 야자지방산 비누 50 ${\sim}$ 100배액 모두 약해를 발생하지 않았으나, 오이에서는 25% 야자지방산 비누 100배액에도 약해를 나타내었다. 12. 이상의 결과, 천연지방산을 이용하여 유기농업에 허용되는 각종의 살충비누를 제조할 수 있었으며, 방제가 조사결과 진딧물, 응애 등 껍질이 연약한 곤충의 방제에 효과적인 것으로 나타났다. 따라서 제조된 살충비누를 활용하면 환경친화적인 해충방제가 가능하다고 판단되었다.

• Korean Journal of Organic Agriculture
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• v.27 no.3
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• pp.341-351
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• 2019

Gynura procumbens (Family Asteraceae) is a medicinal plant commonly found in tropical Asia countries such as China, Thailand, Indonesia, Malaysia, and Vietnam. Traditionally, it is widely used in many different countries for the treatment of a wide variety of health ailments such as kidney discomfort, rheumatism, diabetes mellitus, constipation, and hypertension. The objective of this study was to select the natural growth media for hydroponic cultivation of Gynura procumbens. The commercially available thirty four different organic nutrient solutions were analyzed for growing Gynura procumbens. After analysis, two organic nutrient solution were selected, mixed (pH 5.5~6.5 / EC 0.5~1.0 ds/m) and then used as organic fertilizers. Thirty day old seedlings were planted and the environmental conditions of the rhizosphere were also examined to select the natural media composition. The minimum temperature of rhizosphere by type of natural media was highest in cocopeat media and lowest in perlite media. Furthermore, plant growth was examined from 50 days old seedlings, and vermiculite was observed to be most effective and perlite was the least effective component as natural media. The total polyphenol content of the studied plant material was also higher in vermiculite in comparison to other growth media. The Gynura procumbens yields were also higher in vermiculite in comparison to other growth media. Thus, vermiculite can be used to improve Gynura procumbens plant growth as a natural growth media.

• Journal of agricultural medicine and community health
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• v.40 no.4
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• pp.228-239
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• 2015

Objectives: The purpose of this study was to measure the symptom prevalence of acute pesticide poisoning among farmers in Gyeong-gi province and to investigate the occupational risk factors. Methods: The subjects were 663 farmers using pesticide directly or indirectly and the survey was performed during 2013. 7. 11 - 2014. 8. 27. The data were analyzed by SPSS 21.0. Results: The prevalence of acute pesticide poisoning was 6.63% and dizziness was the most common symptom. Acute pesticide poisoning was related with 'days of pesticide use per year', 'lifetime pesticide application days', 'the number of pesticide mixture' and 'type of farming'. Conclusions: It is necessary to manage and educate the pesticide poisoning-vulnerable group more systematically. Afterward additional study is needed to investigate the farming safety behavior and delicate amount of pesticide exposure.

• Korean journal of applied entomology
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• v.55 no.1
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• pp.45-51
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• 2016

Thirty-seven species of insect pests were surveyed on different area blueberry farms in Jeonbuk province during 2013~2014. Six principal insect pests were found, including Dasineura oxycoccana Johnson, Aphis gossypii Glover, Scirtothrips dorsalis Hood, Ricania sp., Hyphantria cunea Drury, and Latoia consocia Walker. A. gossypii infestation was severe at Iksan and Jinan in middle May. S. dorsalis infestation was severe at all surveyed area in early June, which is the flowering season, and the degree of damage caused was higher in young plants. Ricania sp. was abundant in Jinan and Sunchang, and then appeared to spread across all areas in Jeonbuk. H. cunea had a tendency to concentrate in Iksan during June. Five species of Limacodidae was found, including L. consocia, which was dominant in all areas surveyed, with densities higher then those of the others four species. The degree of damage due to D. oxycoccana was higher in the plain areas (Iksan) than in the middle-mountain areas (Jinan, Sunchang). The rate of damage was 60~78% higher in young plant stages (i.e., those under 3 years of tree age) than in those over 5 years old (30~50%). Moreover, the rate of damage observed in greenhouses was 50~80% higher than that observed in the field (30~40%).